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Observation of Seven Astrophysical Tau Neutrino Candidates with IceCube. PHYSICAL REVIEW LETTERS 2024; 132:151001. [PMID: 38682982 DOI: 10.1103/physrevlett.132.151001] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2023] [Revised: 02/15/2024] [Accepted: 02/29/2024] [Indexed: 05/01/2024]
Abstract
We report on a measurement of astrophysical tau neutrinos with 9.7 yr of IceCube data. Using convolutional neural networks trained on images derived from simulated events, seven candidate ν_{τ} events were found with visible energies ranging from roughly 20 TeV to 1 PeV and a median expected parent ν_{τ} energy of about 200 TeV. Considering backgrounds from astrophysical and atmospheric neutrinos, and muons from π^{±}/K^{±} decays in atmospheric air showers, we obtain a total estimated background of about 0.5 events, dominated by non-ν_{τ} astrophysical neutrinos. Thus, we rule out the absence of astrophysical ν_{τ} at the 5σ level. The measured astrophysical ν_{τ} flux is consistent with expectations based on previously published IceCube astrophysical neutrino flux measurements and neutrino oscillations.
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Observation of high-energy neutrinos from the Galactic plane. Science 2023; 380:1338-1343. [PMID: 37384687 DOI: 10.1126/science.adc9818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Accepted: 05/04/2023] [Indexed: 07/01/2023]
Abstract
The origin of high-energy cosmic rays, atomic nuclei that continuously impact Earth's atmosphere, is unknown. Because of deflection by interstellar magnetic fields, cosmic rays produced within the Milky Way arrive at Earth from random directions. However, cosmic rays interact with matter near their sources and during propagation, which produces high-energy neutrinos. We searched for neutrino emission using machine learning techniques applied to 10 years of data from the IceCube Neutrino Observatory. By comparing diffuse emission models to a background-only hypothesis, we identified neutrino emission from the Galactic plane at the 4.5σ level of significance. The signal is consistent with diffuse emission of neutrinos from the Milky Way but could also arise from a population of unresolved point sources.
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Search for Unstable Sterile Neutrinos with the IceCube Neutrino Observatory. PHYSICAL REVIEW LETTERS 2022; 129:151801. [PMID: 36269964 DOI: 10.1103/physrevlett.129.151801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 08/17/2022] [Accepted: 08/23/2022] [Indexed: 06/16/2023]
Abstract
We present a search for an unstable sterile neutrino by looking for a resonant signal in eight years of atmospheric ν_{μ} data collected from 2011 to 2019 at the IceCube Neutrino Observatory. Both the (stable) three-neutrino and the 3+1 sterile neutrino models are disfavored relative to the unstable sterile neutrino model, though with p values of 2.8% and 0.81%, respectively, we do not observe evidence for 3+1 neutrinos with neutrino decay. The best-fit parameters for the sterile neutrino with decay model from this study are Δm_{41}^{2}=6.7_{-2.5}^{+3.9} eV^{2}, sin^{2}2θ_{24}=0.33_{-0.17}^{+0.20}, and g^{2}=2.5π±1.5π, where g is the decay-mediating coupling. The preferred regions of the 3+1+decay model from short-baseline oscillation searches are excluded at 90% C.L.
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[Clinical features and risk factors for early relapse of pediatric ulcerative colitis]. ZHONGHUA ER KE ZA ZHI = CHINESE JOURNAL OF PEDIATRICS 2022; 60:660-665. [PMID: 35768353 DOI: 10.3760/cma.j.cn112140-20220401-00271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Objective: To investigate the clinical features of pediatric ulcerative colitis (UC) and analyze the risk factors of disease relapse. Methods: The clinical data of 79 children with UC diagnosed in Beijing Children's Hospital, Capital Medical University from January 2016 to February 2021 were retrospectively analyzed. They were divided into early relapse group and non-early relapse group according to the clinical relapse within 12 months after diagnosis. T-test, rank sum test, χ2 test or Fisher's exact test were used to compare the variables between the 2 groups, including the clinical features, laboratory examination results and treatments. The Logistic regression was used to analyze the risk factors of early relapse. The cumulative relapse rate during follow-up was calculated by Kaplan-Meier method. Results: Among the 79 UC children, 46 were males and 33 were females, and the age of onset was 10.6 (6.4, 12.7) years. The children were mainly characterized by extensive disease (E3) and pancolitis (E4) (51/79, 65%), moderate to severe activity (48/79, 61%) and moderate to severe inflammation of colonic mucosa (71/79, 90%). Thirty-eight (48%) patients had atypical phenotype and 17 (22%) had extraintestinal manifestations. The follow-up period was 43.9 (22.8, 61.3) months, and of the 41 patients rechecked with colonoscopy, 7 (17%) had disease progression. According to Kaplan-Meier analysis, the cumulative relapse rate of the 79 cases at 3 months, 6 months, 1 year and 2 years after diagnosis were 27% (21/79), 47% (37/79), 57% (45/79) and 73% (53/73), respectively. There were 45 children (57%) in early relapse group and 34 (43%) in non-early relapse group. In early relapse group, hemoglobin and mucosal healing rate were both significantly lower (105 (87, 122) vs. 120 (104, 131) g/L, 28% (7/25) vs. 7/9, Z=-2.38, χ²=4.87, both P<0.05). The rate of steroid-dependent, E3 and step-up therapy during the induction period were all significantly higher than those in non-early relapse group (11/19 vs. 1/12, 24% (11/45) vs. 6% (2/34), 29% (13/45) vs. 6% (2/34), χ²=5.67, 4.85, 6.66, all P<0.05). Multivariate Logistic regression analysis showed that extraintestinal manifestations (OR=4.33, 95%CI 1.05-17.83), E3 (OR=8.27, 95%CI 1.47-46.46) and step-up therapy during the induction period (OR=5.58, 95%CI 1.01-30.77) were independent risk factors for early relapse. Conclusions: Pediatric UC is usually extensive and severe, with atypical phenotype, a high rate of relapse and a risk of disease progression. Extraintestinal manifestations, E3 and step-up therapy during the induction period are independent risk factors for early relapse.
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Strong Constraints on Neutrino Nonstandard Interactions from TeV-Scale ν_{μ} Disappearance at IceCube. PHYSICAL REVIEW LETTERS 2022; 129:011804. [PMID: 35841552 DOI: 10.1103/physrevlett.129.011804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 06/01/2022] [Indexed: 06/15/2023]
Abstract
We report a search for nonstandard neutrino interactions (NSI) using eight years of TeV-scale atmospheric muon neutrino data from the IceCube Neutrino Observatory. By reconstructing incident energies and zenith angles for atmospheric neutrino events, this analysis presents unified confidence intervals for the NSI parameter ε_{μτ}. The best-fit value is consistent with no NSI at a p value of 25.2%. With a 90% confidence interval of -0.0041≤ε_{μτ}≤0.0031 along the real axis and similar strength in the complex plane, this result is the strongest constraint on any NSI parameter from any oscillation channel to date.
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[Minimally invasive enucleation for benign and low-grade malignant pancreatic tumors: an analysis of 60 cases]. ZHONGHUA WAI KE ZA ZHI [CHINESE JOURNAL OF SURGERY] 2022; 60:674-679. [PMID: 35775260 DOI: 10.3760/cma.j.cn112139-20211219-00612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Objective: To investigate the safety and feasibility of minimally invasive pancreatic tumor enucleation. Methods: The clinicopathological data of 60 patients with minimally invasive pancreatic tumor enucleation admitted to the Department of Pancreatic Surgery of Fudan University Cancer Center from November 2019 to August 2021 were retrospectively analyzed. There were 17 males and 43 females,with age of (50.0±13.2)years(range: 23 to 73 years). Tumors were located in the head of pancreas in 40 cases(66.7%),neck and tail of pancreas in 20 cases(33.3%). Patients were divided into robotic group(n=25) and laparoscopic group(n=35) according to surgical methods. The measurement data were compared by t-test or Mann-Whitney U test, and the categorical data were compared by χ2 test or Fisher exact probability method. The influencing factors of postoperative pancreatic fistula were analyzed by univariate and multivariate Logistic regression. Results: All patients successfully completed tumor enucleation without conversion to laparotomy. The operation time was (183.5±67.3)minutes(range:90 to 410 minutes). Twelve patients(20.0%) underwent stent placement and pancreatic duct repair during operation. The removal time of abdominal drainage tube after operation was (24.7±22.9)days(range:2 to 113 days). The tumor diameter in the robotic group was larger than that in the laparoscopic group((3.5±0.9)cm vs. (2.9±0.7)cm,t=-2.825,P=0.006). The incidences of postoperative biochemical fistula and grade B pancreatic fistula were 20.0%,22.9% and 36.0%,51.4%,respectively(χ²=2.289,P=0.318). There were no grade C pancreatic fistula,lymphatic fistula,biliary fistula,delayed gastric emptying,secondary operation and perioperative death in both groups. Multivariate logistic regression analysis was performed on the occurrence of clinically related pancreatic fistula(above grade B). The results showed that the increase of body mass index(OR=1.285,95%CI:1.053 to 1.569,P=0.014),the larger diameter of the tumor(OR=3.703,95%CI:1.465 to 9.360,P=0.006) and intraoperative pancreatic duct repair(OR=7.889,95%CI:1.471 to 42.296,P=0.016) were independent risk factors,whereas robotic surgery(OR=0.168,95%CI:0.036 to 0.796,P=0.025) was a protective factor. No case of pancreatin dependent dyspepsia and new onset diabetes mellitus was observed. Conclusions: Minimally invasive tumor enucleation is feasible in the treatment of benign and low-grade pancreatic tumors. The incidence of pancreatic fistula is high in the short term after operation,but serious complications are rare. The robot assisted system can reduce the risk of postoperative pancreatic fistula and has more advantages in dealing with larger diameter tumors because of clearer surgical vision and more accurate operation.
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Search for Relativistic Magnetic Monopoles with Eight Years of IceCube Data. PHYSICAL REVIEW LETTERS 2022; 128:051101. [PMID: 35179913 DOI: 10.1103/physrevlett.128.051101] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 12/09/2021] [Accepted: 01/05/2022] [Indexed: 06/14/2023]
Abstract
We present an all-sky 90% confidence level upper limit on the cosmic flux of relativistic magnetic monopoles using 2886 days of IceCube data. The analysis was optimized for monopole speeds between 0.750c and 0.995c, without any explicit restriction on the monopole mass. We constrain the flux of relativistic cosmic magnetic monopoles to a level below 2.0×10^{-19} cm^{-2} s^{-1} sr^{-1} over the majority of the targeted speed range. This result constitutes the most strict upper limit to date for magnetic monopoles with β≳0.8 and up to β∼0.995 and fills the gap between existing limits on the cosmic flux of nonrelativistic and ultrarelativistic magnetic monopoles.
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[Effect of laparoscopic surgery for pancreatic cancer after neoadjuvant chemotherapy]. ZHONGHUA WAI KE ZA ZHI [CHINESE JOURNAL OF SURGERY] 2022; 60:134-139. [PMID: 35012272 DOI: 10.3760/cma.j.cn112139-20210823-00389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Objective: To evaluate the safety and feasibility of laparoscopic surgery after neoadjuvant chemotherapy for pancreatic cancer. Methods: Clinical data of 8 patients underwent laparoscopic surgery after neoadjuvant chemotherapy for pancreatic cancer at Fudan University Shanghai Cancer Center from September 2019 to June 2020 were reviewed retrospectively. There were 5 males and 3 females,aged from 47 to 72 years old. All patients underwent abdominal enhanced CT and PET-CT before operation to accurately evaluate the tumor stage and exclude distant metastasis. Results: Neoadjuvant chemotherapy with AG regimen(gemcitabine 1 000 mg/m2 and albumin bound paclitaxel 125 mg/m2) was received for 2 to 6 cycles before surgery. All 8 patients successfully completed the operation,including 5 cases of pancreaticoduodenectomy,2 cases of radical antegrade modular pancreatosplenectomy(RAMPS),and 1 case of total pancreatectomy. No conversion to laparotomy or laparoscopic assisted surgery. The operation time was 240 to 450 minutes,the blood loss was 100 to 500 ml,the postoperative length of stay was 10 to 16 days. During the follow-up period up to December 31, 2020, there was 1 case suffered grade B pancreatic leakage and abdominal infection. The numbers of resected lymph nodes were 9 to 31. All patients received R0 resection. The follow-up times were 4.5 to 9.5 months. One patient underwent RAMPS was diagnosed as liver metastasis after 2 months of the operation,and the other 7 patients still survived without tumor recurrence. Conclusion: Minimally invasive surgery of pancreatic cancer after neoadjuvant chemotherapy is safe and feasible in experienced pancreatic minimally invasive centers.
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[Ketogenic parenteral nutrition in a case of developmental and epileptic encephalopathy caused by GABRB2 gene variation]. ZHONGHUA ER KE ZA ZHI = CHINESE JOURNAL OF PEDIATRICS 2021; 59:1092-1094. [PMID: 34856672 DOI: 10.3760/cma.j.cn112140-20210606-00487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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[Advances in basic and translational research in neuroendocrine neoplasms]. ZHONGHUA WEI CHANG WAI KE ZA ZHI = CHINESE JOURNAL OF GASTROINTESTINAL SURGERY 2021; 24:867-874. [PMID: 34674461 DOI: 10.3760/cma.j.cn.441530-20210705-00261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
With the development of diagnostic techniques and the improvement of people's living standards, the detection rate of neuroendocrine tumor has been increasing and people are paying more and more attention to it. With multiple treatment modalities, the clinical research progress of neuroendocrine tumor is remarkable. However, due to the tumor heterogeneity, metastasis and recurrence of neuroendocrine tumor remains a difficult problem for clinicians. The efficacy of neuroendocrine tumor still needs to be improved. Therefore, the biological behavior of neuroendocrine tumor needs to be further studied. In recent years, with the development of molecular biology, the basic and transformation research of neuroendocrine tumor has made some progress. In this paper, we focus on the hot topics of neuroendocrine tumor, such as multiomics (copy number variation, genomics, transcriptomics), tumor microenvironment (immune microenvironment, tumor microvasculature, tumor-associated fibroblasts, etc.), preclinical research model construction (cell lines, organoids, patient derived xenograft models, genetically engineered mice), etc. Specifically, the related clinical transformation significance will be elaborated.
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[A cross-sectional investigation on the current status and influencing factors of kinesiophobia in adult burn patients]. ZHONGHUA SHAO SHANG ZA ZHI = ZHONGHUA SHAOSHANG ZAZHI = CHINESE JOURNAL OF BURNS 2021; 37:575-581. [PMID: 34139829 DOI: 10.3760/cma.j.cn501120-20200618-00313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Objective: To investigate the current status and influencing factors of kinesiophobia in adult burn patients. Methods: A single center cross-sectional research method was conducted. A total of 170 adult burn patients, meeting the inclusion criteria, were admitted to the Department of Plastic Surgery and Burns of the West China Hospital of Sichuan University from October 2018 to December 2019. On admission, the self-made general information questionnaire was used to investigate the gender, age, education level, marital status, payment method of medical expenses, injury factors, and total burn area of patients. One month after admission or before discharge, the presence and degree of kinesiophobia of patients were evaluated by the Tampa Scale for Kinesiophobia (TSK), their pain degrees (results averaged) at the time of burn, debridement and dressing change, after burn operation, and at rest were evaluated by the Visual Analogue Scale, their social support levels were evaluated by the Social Support Revalued Scale, and their degrees of anxiety and depression were evaluated by the Hospital Anxiety and Depression Scale. According to the TSK score, the patients with score >37 points were included into kinesiophobia group, and the patients with score ≤37 points were included into non-kinesiophobia group. The general information of patients in the two groups, as well as the pain score, social support level score, anxiety score, and depression score mentioned above, were recorded. Data of patients between the two groups were statistically analyzed with unifactor analysis including chi-square test, independent sample t test, and Mann-Whitney U test. The factors with statistically significant differences in unifactor analysis were used as variables for multivariate logistic regression analysis to screen out the independent influencing factors of kinesiophobia in adult burn patients. Results: Questionnaires and scales of 170 patients were collected, and the recovery rate was 100%. The data of two patients complicated with cranial fracture aggravation were removed, and 168 valid data were obtained, with the effective rate of 98.82%. Among the 168 patients, 88 were male (52.38%) and 80 were female (47.62%), aged from 18 to 71 (41±6) years. Most of the patients had secondary school education or below, were married, and with no out-of-pocket medical expenses. The main factors of injury were flame and hydrothermal fluid, and the total burn area was 2%-75% ((28±5)%) total body surface area. The TSK score was (41±5) points, the pain score was 4.0 (2.6, 7.0) points, the social support level score was (40±5) points, the anxiety score was 8.5 (7.0, 13.0) points, and the depression score was 9.5 (6.5, 12.0) points. A total of 98 patients had kinesiophobia, and the incidence of kinesiophobia was 58.33%. There were no statistically significant differences in gender, age, educational level, marital status, or injury factors of patients between kinesiophobia group and non-kinesiophobia group (P>0.05). The percentage of out-of-pocket expenses, total burn area, pain score, anxiety score, and depression score of patients in kinesiophobia group were significantly higher than those in non-kinesiophobia group (χ2=6.402, t=2.39, Z=-8.05, -6.68, -7.89, P<0.05 or P<0.01), and the social support level score of patients in kinesiophobia group was significantly lower than that in non-kinesiophobia group (t=5.22, P<0.01). The multivariate logistic regression analysis showed that total burn area, pain score, social support level score, anxiety score, and depression score were the independent influencing factors for the development of kinesiophobia in adult burn patients (odds ratio=0.79, 1.45, 0.78, 1.15, 1.17, 95% confidence interval=0.80-0.92, 1.24-1.74, 0.65-0.91, 1.06-1.29, 1.03-1.24, P<0.01). Conclusions: The incidence of kinesiophobia in adult burn patients is high, and the degree of kinesiophobia is mainly affected by total burn area, pain, social support level, anxiety and depression degrees, and so on. Thus these factors should be taken into consideration when designing interventions to reduce the incidence and degree of kinesiophobia.
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eV-Scale Sterile Neutrino Search Using Eight Years of Atmospheric Muon Neutrino Data from the IceCube Neutrino Observatory. PHYSICAL REVIEW LETTERS 2020; 125:141801. [PMID: 33064514 DOI: 10.1103/physrevlett.125.141801] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Accepted: 08/31/2020] [Indexed: 06/11/2023]
Abstract
The results of a 3+1 sterile neutrino search using eight years of data from the IceCube Neutrino Observatory are presented. A total of 305 735 muon neutrino events are analyzed in reconstructed energy-zenith space to test for signatures of a matter-enhanced oscillation that would occur given a sterile neutrino state with a mass-squared differences between 0.01 and 100 eV^{2}. The best-fit point is found to be at sin^{2}(2θ_{24})=0.10 and Δm_{41}^{2}=4.5 eV^{2}, which is consistent with the no sterile neutrino hypothesis with a p value of 8.0%.
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Characteristics of the Diffuse Astrophysical Electron and Tau Neutrino Flux with Six Years of IceCube High Energy Cascade Data. PHYSICAL REVIEW LETTERS 2020; 125:121104. [PMID: 33016752 DOI: 10.1103/physrevlett.125.121104] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2020] [Revised: 06/02/2020] [Accepted: 07/20/2020] [Indexed: 06/11/2023]
Abstract
We report on the first measurement of the astrophysical neutrino flux using particle showers (cascades) in IceCube data from 2010-2015. Assuming standard oscillations, the astrophysical neutrinos in this dedicated cascade sample are dominated (∼90%) by electron and tau flavors. The flux, observed in the sensitive energy range from 16 TeV to 2.6 PeV, is consistent with a single power-law model as expected from Fermi-type acceleration of high energy particles at astrophysical sources. We find the flux spectral index to be γ=2.53±0.07 and a flux normalization for each neutrino flavor of ϕ_{astro}=1.66_{-0.27}^{+0.25} at E_{0}=100 TeV, in agreement with IceCube's complementary muon neutrino results and with all-neutrino flavor fit results. In the measured energy range we reject spectral indices γ≤2.28 at ≥3σ significance level. Because of high neutrino energy resolution and low atmospheric neutrino backgrounds, this analysis provides the most detailed characterization of the neutrino flux at energies below ∼100 TeV compared to previous IceCube results. Results from fits assuming more complex neutrino flux models suggest a flux softening at high energies and a flux hardening at low energies (p value ≥0.06). The sizable and smooth flux measured below ∼100 TeV remains a puzzle. In order to not violate the isotropic diffuse gamma-ray background as measured by the Fermi Large Area Telescope, it suggests the existence of astrophysical neutrino sources characterized by dense environments which are opaque to gamma rays.
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[Establishment of clinical features and prognostic scoring model in early-stage hepatitis B-related acute-on-chronic liver failure]. ZHONGHUA GAN ZANG BING ZA ZHI = ZHONGHUA GANZANGBING ZAZHI = CHINESE JOURNAL OF HEPATOLOGY 2020; 28:441-445. [PMID: 32403883 DOI: 10.3760/cma.j.cn501113-20200316-00116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To explore the clinical characteristics and establish a corresponding prognostic scoring model in patients with early-stage clinical features of hepatitis B-induced acute-on-chronic liver failure (HBV-ACLF). Methods: Clinical characteristics of 725 cases with hepatitis B-related acute-on-chronic hepatic dysfunction (HBV-ACHD) were retrospectively analyzed using Chinese group on the study of severe hepatitis B (COSSH). The independent risk factors associated with 90-day prognosis to establish a prognostic scoring model was analyzed by multivariate Cox regression, and was validated by 500 internal and 390 external HBV-ACHD patients. Results: Among 725 cases with HBV-ACHD, 76.8% were male, 96.8% had cirrhosis base,66.5% had complications of ascites, 4.1% had coagulation failure in respect to organ failure, and 9.2% had 90-day mortality rate. Multivariate Cox regression analysis showed that TBil, WBC and ALP were the best predictors of 90-day mortality rate in HBV-ACHD patients. The established scoring model was COSS-HACHADs = 0.75 × ln(WBC) + 0.57 × ln(TBil)-0.94 × ln(ALP) +10. The area under the receiver operating characteristic curve (AUROC) of subjects was significantly higher than MELD, MELD-Na, CTP and CLIF-C ADs(P < 0.05). An analysis of 500 and 390 cases of internal random selection group and external group had similar verified results. Conclusion: HBV-ACHD patients are a group of people with decompensated cirrhosis combined with small number of organ failure, and the 90-day mortality rate is 9.2%. COSSH-ACHDs have a higher predictive effect on HBV-ACHD patients' 90-day prognosis, and thus provide evidence-based medicine for early clinical diagnosis and treatment.
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Time-Integrated Neutrino Source Searches with 10 Years of IceCube Data. PHYSICAL REVIEW LETTERS 2020; 124:051103. [PMID: 32083934 DOI: 10.1103/physrevlett.124.051103] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 12/13/2019] [Accepted: 01/06/2020] [Indexed: 06/10/2023]
Abstract
This Letter presents the results from pointlike neutrino source searches using ten years of IceCube data collected between April 6, 2008 and July 10, 2018. We evaluate the significance of an astrophysical signal from a pointlike source looking for an excess of clustered neutrino events with energies typically above ∼1 TeV among the background of atmospheric muons and neutrinos. We perform a full-sky scan, a search within a selected source catalog, a catalog population study, and three stacked Galactic catalog searches. The most significant point in the northern hemisphere from scanning the sky is coincident with the Seyfert II galaxy NGC 1068, which was included in the source catalog search. The excess at the coordinates of NGC 1068 is inconsistent with background expectations at the level of 2.9σ after accounting for statistical trials from the entire catalog. The combination of this result along with excesses observed at the coordinates of three other sources, including TXS 0506+056, suggests that, collectively, correlations with sources in the northern catalog are inconsistent with background at 3.3σ significance. The southern catalog is consistent with background. These results, all based on searches for a cumulative neutrino signal integrated over the 10 years of available data, motivate further study of these and similar sources, including time-dependent analyses, multimessenger correlations, and the possibility of stronger evidence with coming upgrades to the detector.
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[Pay attention to the research of artificial intelligence in central nervous system imaging]. ZHONGHUA YI XUE ZA ZHI 2020; 100:161-164. [PMID: 32008279 DOI: 10.3760/cma.j.issn.0376-2491.2020.03.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Stomatal Sensitivity to Vapor Pressure Deficit and the Loss of Hydraulic Conductivity Are Coordinated in Populus euphratica, a Desert Phreatophyte Species. FRONTIERS IN PLANT SCIENCE 2020; 11:1248. [PMID: 32922423 PMCID: PMC7456922 DOI: 10.3389/fpls.2020.01248] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 07/29/2020] [Indexed: 05/03/2023]
Abstract
There are considerable variations in the percentage loss of hydraulic conductivity (PLC) at mid-day minimum water potential among and within species, but the underpinning mechanism(s) are poorly understood. This study tested the hypothesis that plants can regulate leaf specific hydraulic conductance (K l) via precise control over PLC under variable ΔΨ (water potential differential between soil and leaf) conditions to maintain the -m/b constant (-m: the sensitivity of stomatal conductance to VPD; b: reference stomatal conductance at 1.0 kPa VPD), where VPD is vapor pressure deficit. We used Populus euphratica, a phreatophyte species distributed in the desert of Northwestern China, to test the hypothesis. Field measurements of VPD, stomatal conductance (g s), g s responses to VPD, mid-day minimum leaf water potential (Ψ lmin), and branch hydraulic architecture were taken in late June at four sites along the downstream of Tarim River at the north edge of the Taklamakan desert. We have found that: 1) the -m/b ratio was almost constant (=0.6) across all the sites; 2) the average Ψ 50 (the xylem water potential with 50% loss of hydraulic conductivity) was -1.63 MPa, and mid-day PLC ranged from 62 to 83%; 3) there were tight correlations between Ψ 50 and wood density/leaf specific hydraulic conductivity (k l) and between specific hydraulic conductance sensitivity to water potential [d(k s)/dln(-Ψ)] and specific hydraulic conductivity (k s). A modified hydraulic model was applied to investigate the relationship between g s and VPD under variable ΔΨ and K l conditions. It was concluded that P. euphratica was able to control PLC in order to maintain a relatively constant -m/b under different site conditions. This study demonstrated that branchlet hydraulic architecture and stomatal response to VPD were well coordinated in order to maintain relatively water homeostasis of P. euphratica in the desert. Model simulations could explain the wide variations of PLC across and within woody species that are often observed in the field.
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[Genetic characterization of influenza A virus and assessment of vaccine efficacy in Yantai from 2014 to 2017]. ZHONGHUA YU FANG YI XUE ZA ZHI [CHINESE JOURNAL OF PREVENTIVE MEDICINE] 2019; 53:840-842. [PMID: 31378046 DOI: 10.3760/cma.j.issn.0253-9624.2019.08.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
In this study, the swabs were collected among patients with an influenza-like illness (ILI) admitted to 2 sentinel surveillance hospitals of Yantai from April 2014 to August 2017. All specimen were cultured and identified by hemagglutination inhibition assay. Complete sequences of Hemagglutinin (HA) of influenza A were amplified, sequenced and analyzed using molecular and phylogenetic methods. The potential vaccine efficacy were calculated using Pepitope model. The results showed that the antigenicity of A (H3N2) had changed greatly. 8 strains of influenza A (H1N1) pdm09 belonged to subclade 6B.1 and 14 strains clustered in 6B.2. 12 strains of influenza A (H3N2) fell into subgroup 3C.3a and 33 strains clustered in 3C.2a. Several residues at antigen sites and potential glycosylation sites had changed in influenza A strains. Vaccine efficacy of influenza A (H1N1) pdm09 in 2015/2016 and 2016/2017 seasons were 77.29% and 79.11% of that of a perfect match with vaccine strain, meanwhile vaccine efficacy of influenza A (H3N2) in 2014/2015, 2015/2016 and 2016/2017 were-5.18%, 16.97% and 42.05% separately. In conclusion, the influenza A virus circulated in Yantai from 2014 to 2017 presented continual genetic variation. The recommended vaccine strains still afforded protection against influenza A (H1N1) pdm09 strains and provided suboptimal protection against influenza A (H3N2) strains.
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[Preliminary evaluation of endoscopic selective varices devascularization in children]. ZHONGHUA ER KE ZA ZHI = CHINESE JOURNAL OF PEDIATRICS 2019; 57:526-531. [PMID: 31269552 DOI: 10.3760/cma.j.issn.0578-1310.2019.07.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To investigate the effect of the endoscopic selective varices devascularization (ESVD) for the esophageal gastric varices bleeding (EGVB) in children. Methods: The clinical data of the patients diagnosed with EGVB and treated with ESVD from January 2018 to March 2018 were retrospectively analyzed. The effects, safety and complications of ESVD were evaluated. Results: There were five patients (including 2 males and 3 females, age ranged from 4 to 7 years) in the study. No rebleeding was found at the first follow-up on one week post operation. Three patients were treated with the endo-therapy at the twice follow-up (3 months after surgery): 2 patients had ESVD again and 1 patient had resection under endoscopy due to stenosis caused by surgical scar. After the second procedure, there was no rebleeding but one patient had abdominal pain caused by mesenteric thrombosis, cured with low molecular weight heparin. Conclusion: The ESVD for EGVB is safe and effective, but the long-term curative effect should be further studied.
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[Laparoscopic radical antegrade modular pancreatosplenectomy for left-sided pancreatic adenocarcinoma: analysis of 12 cases]. ZHONGHUA WAI KE ZA ZHI [CHINESE JOURNAL OF SURGERY] 2019. [PMID: 29534416 DOI: 10.3760/cma.j.issn.0529-5815.2018.03.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To evaluate the safety and feasibility of laparoscopic radical antegrade modular pancreatosplenectomy(Lap-RAMPS) for left-sided pancreatic adenocarcinoma. Methods: Clinical data of total 12 patients underwent Lap-RAMPS for left-sided pancreatic adenocarcinoma at Department of Gastrointestinal and Pancreatic Surgery, Zhejiang Provincial People's Hospital from March 2016 to August 2017 were reviewed retrospectively.There were 7 male patients and 5 female patients, with median age of 60.5 years old(47-68 years old). Abdominal enhanced CT, pancreatic MRI, PET-CT were performed on all patients to evaluate the lesion and exclude metastasis.Follow-up were done with out-patient clinic or telephone consultancy until October 2017. Results: All patients underwent pure Lap-RAMPS.The medium operative time was 250 minutes(180-445 minutes), and the blood loss was 150 ml(50-500 ml). The medium first flatus time and diet resumption time were 3.0 days(1-5 days) and 3.5 days(1-7 days) respectively.The medium postoperative hospital stay was 9 days(4-18 days). Morbidity occurred in 8 patients with gastric empty delay(n=1), bleeding(n=1), fluid collection(n=3). There was no mortality.The medium overall number of retrived lymph nodes was 15.6 and the positive rate was 41.7%. The R0 rate was 100%.The medium follow-up was 10 months.One patient was diagnosed as liver metastasis after 8 months and accepted chemotherapy.One patient died after 14 months for tumor recurrence and metastasis.Others survived without tumor recurrence or metasitasis. Conclusion: Lap-RAMPS is safe and feasible with accepted oncological outcomes for selected left side pancreatic adenocarcinoma under skilled hands.
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[Clinical analysis of eosinophilic gastroenteritis in 71 children]. ZHONGHUA ER KE ZA ZHI = CHINESE JOURNAL OF PEDIATRICS 2019; 56:500-504. [PMID: 29996182 DOI: 10.3760/cma.j.issn.0578-1310.2018.07.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To summarize the clinical data including manifestations, diagnosis, treatment and prognosis of eosinophilic gastroenteritis (EGE) in children. Methods: A retrospective analysis was performed in 71 patients with pathologically proven EGE at Beijing Children's Hospital Affiliated to Capital Medical University from January 2008 to January 2017. Their clinical manifestations, laboratory and imaging examinations, endoscopic findings, histopathological examinations, and treatment were collected and analyzed. Results: Among 71 EGE cases, 47 (66%) cases were male and 24 (34%) cases were female, and the median age was 9.2 (0.2-16.5) years old. The main clinical manifestations included abdominal pain (76%, 54/71), vomiting (68%, 48/71), anorexia (54%, 38/71), weight loss (38%, 27/71), and diarrhea (37%, 26/71). There were 27 cases (38%) with a history of allergic diseases or family history. The median absolute value of eosinophil in peripheral blood of the 71 patients was 0.4 (0-36.8)×10(9)/L, and 27 cases (38%) showed an increase in eosinophil counts. Serum IgE was measured in 52 patients (104.3 (3.4- 3 000.0)×10(3) U/L), and 30 patients (58%) showed an increase in serum IgE. A large number of eosinophils ((41.0±8.5)/HP) were found in 3 patients' ascites. The endoscopic examination of upper gastrointestinal tract revealed hyperemic edema in 62 cases (87%), plaque in 44 cases (62%), erosion in 17 cases (24%) and ulceration in 16 cases (23%). Histopathologically, in 8 cases (11%) the disease involved both stomach and duodeneum, in 21 cases (30%) involved stomach only, and in 37 cases (52%) involved duodeneum only. In addition, in 6 cases (8%) the disease involved esophagus and in 10 cases (14%) involved colorectum. Microscopically, eosinophil counts averaged 67/HP, 33/HP, 40/HP and 38/HP in esophageal, gastric, duodenal and colorectal mucosa respectively. A total of 34 cases were treated with glucocorticoid, and all these patients had alleviation of symptoms, which occurred within 14.9 days on average, but EGE recurred in 11 cases (32%). Conclusions: The clinical symptoms and endoscopic findings of EGE are diverse and nonspecific. Histopathological examination of gastrointestinal mucosa is particularly important for the diagnosis. Glucocorticoid treatment is effective, but the patients with EGE are prone to relapse.
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Analysis of Late Positive Component of Event-related Potentials by Face Expression Images in Traumatic Brain Injury Patients with Mood Disorders. FA YI XUE ZA ZHI 2019; 34:640-643. [PMID: 30896103 DOI: 10.12116/j.issn.1004-5619.2018.06.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Indexed: 11/30/2022]
Abstract
OBJECTIVES To explore the application of event-related potentials (ERP) by positive, negative, and neutral face expression images in the evaluation of mood disorders in brain traumatic patients. METHODS ERP was tested by face expression images in 24 patients mainly with anxiety and depression symptoms (depression group) and 19 patients mainly with hostile and suspicion symptoms (hostile group), respectively. The findings were compared with those of the control group. RESULTS There were no significant differences, between the depression group and the hostile group, on latencies and amplitudes of late positive potential (LPP) induced by the three types of face expression images, except the amplitude induced by negative face expression image. Compared with the control group, the latencies were extended and the amplitudes were lower in both depression and hostile groups. Within each group, the difference of latencies induced by the three images was not significant. The amplitudes induced by negative face expression image was higher than those induced by positive and neutral face expression images, with significant differences in the hostile group and the control group (P<0.05) but not in the depression group. CONCLUSIONS Changes in latencies and amplitudes of LPP could be an objective indicator in the evaluation of mood disorders of brain traumatic patients. The LPP induced by negative face expression images could be more meaningful for patients mainly with anxiety and depression symptoms.
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Constraints on Minute-Scale Transient Astrophysical Neutrino Sources. PHYSICAL REVIEW LETTERS 2019; 122:051102. [PMID: 30822017 DOI: 10.1103/physrevlett.122.051102] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 11/12/2018] [Indexed: 06/09/2023]
Abstract
High-energy neutrino emission has been predicted for several short-lived astrophysical transients including gamma-ray bursts (GRBs), core-collapse supernovae with choked jets, and neutron star mergers. IceCube's optical and x-ray follow-up program searches for such transient sources by looking for two or more muon neutrino candidates in directional coincidence and arriving within 100 s. The measured rate of neutrino alerts is consistent with the expected rate of chance coincidences of atmospheric background events and no likely electromagnetic counterparts have been identified in Swift follow-up observations. Here, we calculate generic bounds on the neutrino flux of short-lived transient sources. Assuming an E^{-2.5} neutrino spectrum, we find that the neutrino flux of rare sources, like long gamma-ray bursts, is constrained to <5% of the detected astrophysical flux and the energy released in neutrinos (100 GeV to 10 PeV) by a median bright GRB-like source is <10^{52.5} erg. For a harder E^{-2.13} neutrino spectrum up to 30% of the flux could be produced by GRBs and the allowed median source energy is <10^{52} erg. A hypothetical population of transient sources has to be more common than 10^{-5} Mpc^{-3} yr^{-1} (5×10^{-8} Mpc^{-3} yr^{-1} for the E^{-2.13} spectrum) to account for the complete astrophysical neutrino flux.
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[Strategy in management of adjacent organ lesion during laparoscopic pancreaticoduodenectomy]. ZHONGHUA WAI KE ZA ZHI [CHINESE JOURNAL OF SURGERY] 2018; 56:522-527. [PMID: 30032534 DOI: 10.3760/cma.j.issn.0529-5815.2018.07.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To evaluate the safety and feasible of adjacent organ resection during laparoscopic pancreaticoduodenectomy(LPD), and summary the surgical strategies. Methods: Clinical data of 15 adjacent organ resections combined with LPD from March 2013 to September 2017 were reviewed.There were 10 male and 5 female patients aging from 20 to 86 years, and the body mass index ranged from 19.6 to 34.5 kg/m(2).Two patients had previous abdominal surgical history.Two patients underwent preoperative chemotherapy. Results: The resected adjacent organs included liver(n=4), stomach(n=3), colon(n=6), right kidney with embolectomy and vasoplastic of inferior vena cava(n=1), and spleen artery aneurysms(n=1). The operative time ranged from 280 to 450 minutes, and the blood loss ranged from 100 to 450 ml.The total complication rate was 5/15 and no one died in 90 days after surgery.The postoperative hospital stay ranged from 10 to 42 days with medium 18 days.The pathology included adenocarcinoma of stomach and duodenum(n=1), gastric cancer invading pancreas or duodenum(n=2), ampullary adenocarcinoma with left hepatolithiasis(n=1), ampullary adenocarcinoma with a benign lesion in left liver(n=1), ampullary adenocarcinoma with single liver metastasis(n=1), ampullary adenocarcinoma(n=1), pancreatic intraductal papillary mucinous neoplasm with splenic artery aneurysms(n=1), pancreatic neuroendocrine neoplasm with colon cancer(n=1), distal common bile duct adenocarcinoma involving righ hepatic duct(n=1), pancreatic neuroendocrine neoplasm invading inferior vena cava and right renal vein(n=1), duodenal adnocarcinoma(n=1), duodenal ewing's sarcoma(n=1), duodenal intesititialoma(n=2). The follow-up was from 3 to 40 months with the medium survival of 17.5 months. Conclusions: The oncological outcomes of PD combined with adjacent organ resection is acceptable.Surgical treatment for those patients with periampullary neoplasma and adjacent organ lesions should be aggressive.
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[Clinical analysis of intestinal lymphangiectasia in 47 children]. ZHONGHUA ER KE ZA ZHI = CHINESE JOURNAL OF PEDIATRICS 2017; 55:937-941. [PMID: 29262475 DOI: 10.3760/cma.j.issn.0578-1310.2017.12.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Objective: To analyze the clinical manifestations, diagnosis, treatment and prognosis of intestinal lymphangiectasia (IL) in children in order to improve the skills of diagnosis and treatment of IL. Method: Clinical manifestations, laboratory findings, gastroscopic findings, histopathological examinations and lymphatic radionuclide imaging assessments were analyzed retrospectively among 47 IL patients who were hospitalized in the Gastroenterology Department of Beijing Children's Hospital Affiliated to Capital Medical University from June 2007 to December 2015. All patients were followed up by telephone. According to the various causes, the patients were divided into the primary intestinal lymphangiectasia (PIL) group and secondary IL group, and their clinical manifestations were compared by t test, Rank sum test or Chi-square test. Result: In 47 IL patients, there were 38 children (81%) younger than 3 years old. There were 43 PIL patients (91%) and 4 secondary IL patients (9%). Between PIL and secondary IL, there were statistical differences in serum albumin (t=-3.950, P<0.005) , globulin(t=-2.850, P=0.007), age of onset(U=27.000, P=0.024), age at diagnosis(U=29.000, P=0.030) and course of disease(U=26.500, P=0.023), whereas there were no statistical differences in lymphocyte count, IgG, lymphatic radionuclide imaging, histopathology and gender(all P>0.05). Edema (44 cases, 94%), diarrhea (42 cases, 89%), accompanied with infection (35 cases, 74%) and ascites (30 cases, 64%) were the main clinical manifestations. In 47 IL patients, 45 patients were done gastroscopy and histopathological examinations, and there were 31 patients' histopathological examinations(69%) were positive. Forty patients were done lymphatic radionuclide imaging, and there was evidence of protein losing from gut via lymphatic radionuclide imaging in 39 patients(98%). Among 47 patients, 35 patients (74%) were followed up, 32 patients had good prognosis, 2 patient failed to show evidence of improvement, 1 patient died and no patient experienced a relapse till the end of the follow-up. In 35 patients, 28 patients were treated with medium chain triglycerides (MCT) dietary therapy, 26 patients showed improvement in symptoms, and 2 patients had no improvement. Among 35 patients with follow-up, there were 6 patients received surgical treatment, and their symptoms were improved. Conclusion: PIL are the majority of IL in children younger than 3 years old. The main clinical manifestations are edema, diarrhea, accompanied with infection and ascites. For the patients without the evidence of lymphangiectasia from duodenum histopathological examination, further consideration of lymphatic radionuclide imaging, clinical manifestations, and laboratory studies are needed to make a final diagnosis. MCT dietary therapy is the cornerstone of IL medical management.
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[Colonization rate of Clostridium Difficile in healthy children]. ZHONGHUA ER KE ZA ZHI = CHINESE JOURNAL OF PEDIATRICS 2017; 55:294-297. [PMID: 28441827 DOI: 10.3760/cma.j.issn.0578-1310.2017.04.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To learn the colonization of Clostridium difficile in local healthy children and to investigate the colonization rate and toxin types of Clostridium difficile at different ages. Method: From September 2014 to January 2015 in a case observational study, healthy children's fecal specimens from the health care department of Beijing Children's Hospital were collected. The children were divided into four groups according to age: <1 year old(n=53), 1-<3 years old(n=50), 3-<6 years old(n=50) and 6-<14 years old(n=50) respectively. Polymerase chain reaction (PCR) was used to detect Clostridium difficile toxin genes including tcdA, tcdB, binary toxin CDT (cdtA and cdtB), and toxin regulatory genes including tcdC, tcdD and tcdE. And then the positive samples were sequenced. Measurement data were compared by using t test and rank sum test, while, enumeration data were compared using chi-square test. Result: Fifteen (7.4%) specimens were positive for Clostridium difficile toxin genes in 203 stool specimens. Of the 15 positive specimens, eight(53.3%) were tcdA(+) tcdB(-)(A(+) B(-)), four were A(+) B(+) , 3(20.0%) were A(-)B(+) , the binary toxin-positive specimens were not detected. TcdC, tcdD, tcdE positive specimens were 8, 6 and 11, respectively. Gene mutations were not found in positive samples by DNA sequencing. In the 15 positive samples, four (7.5%) specimens were in <1 year old group; four (8.0%) specimens were in 1-<3 years old group; one(2.0%) specimen was in 3-<6 years old group; and 6(12.0%) specimens were in 6-<14 years old group. The colonization rate had no significance in different age groups. Conclusion: The colonization rate of Clostridium difficile in healthy children was 7.4%. And toxigenic Clostridium difficile can be detected in all age groups.
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[Clinical analysis of 11 children with pancreatic cystic fibrosis]. ZHONGHUA ER KE ZA ZHI = CHINESE JOURNAL OF PEDIATRICS 2017; 55:373-376. [PMID: 28482390 DOI: 10.3760/cma.j.issn.0578-1310.2017.05.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To increase the recognition of pancreatic cystic fibrosis (PCF) in children and facilitate diagnosing and treatment of this rare entity. Method: This is a retrospective analysis of children who presented to Beijing Children's Hospital affiliated to Capital Medical University from January 2010 to December 2015. We describe their clinical features, laboratory testing and management. Result: Eleven children were diagnosed with PCF by genetic testing or sweat chloride test during these 5 years, including 4 boys and 7 girls. Their age ranged from 0.5-14.3 (mean 9.0±3.9) years. Family history was positive in 3 children. Significant clinical findings on presentation were: malnutrition 6, including 2 cases of mild, moderate and severe malnutrition each; diarrhea 4 (yellow mushy or watery stool with frequency ranging from 2-5 times a day), including 1 case of acute diarrhea and 3 of chronic diarrhea, 3 of them had steatorrhea; abdominal pain 3. All of them had pancreatic lesions shown by abdominal ultrasound. Blood tests showed 6 cases had elevated serum amylase and lipase. The main treatment was pancreatic replacement therapy and nutritional support. Conclusion: PCF is rare in children. Malnutrition, diarrhea and abdominal pain are the main clinical manifestations. Treatment is mostly pancreatic enzymes replacement and supportive care.
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[Laparoscopic pancreaticoduodenectomy: a report of 233 cases by a single team]. ZHONGHUA WAI KE ZA ZHI [CHINESE JOURNAL OF SURGERY] 2017; 55:354-358. [PMID: 28464575 DOI: 10.3760/cma.j.issn.0529-5815.2017.05.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To summary the experience of 233 cases of laparoscopic pancreaticoduodenectomy (LPD) performed by a single surgical team. Methods: Data of patients undergoing LPD from September 2012 to October 2016 were reviewed. There were 145 males and 88 females with the mean age of(60.3±13.0)years old, ranging from 19 to 92 years old, and the mean body mass index of (22.8±3.5)kg/m(2,) ranging from 16.3 to 36.8 kg/m(2). There were 195 patients with clinical manifestation and 54 patients who had the history of abdominal surgery. Results: LPD were performed on 233 patients by same surgical team consecutively. The mean operative time was(368.0±57.4)minutes. Mean blood loss was(203.8±138.6)ml. The postoperative morbidity rate was 33.5%, with 6.9% of grade B or C pancreatic fistula and 9.9% of bleeding. The reoperation rate was 5.6%. The mortality during 30 days after operation was 0.9%. Mean postoperative hospital stay was (18.1±11.2)days. Mean tumor size was (3.9±2.4)cm, and the mean number of lymph nodes harvested was 21.3±11.9.One hundred and sixty-three patients were diagnosed as malignant tumor, including pancreatic adenocarcinoma(n=84), cholangiocarcinoma(n=17), ampullary adenocarcinoma(n=55), duodenal adenocarcinoma(n=5), gastric cancer(n=1)and duel cancer (n=1) located in distal stomach and duodenum. Conclusion: The key point to make laparoscopic pancreaticduodenectomy a routine safe procedure is to operate the procedure under skilled hands in selected patients via suitable surgical approaches.
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[Primary extraskeletal osteosarcoma of thoracic cavity with lung metastasis: report of a case]. ZHONGHUA BING LI XUE ZA ZHI = CHINESE JOURNAL OF PATHOLOGY 2017; 46:126-127. [PMID: 28173679 DOI: 10.3760/cma.j.issn.0529-5807.2017.02.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
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Constraints on Ultrahigh-Energy Cosmic-Ray Sources from a Search for Neutrinos above 10 PeV with IceCube. PHYSICAL REVIEW LETTERS 2016; 117:241101. [PMID: 28009216 DOI: 10.1103/physrevlett.117.241101] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Indexed: 06/06/2023]
Abstract
We report constraints on the sources of ultrahigh-energy cosmic rays (UHECRs) above 10^{9} GeV, based on an analysis of seven years of IceCube data. This analysis efficiently selects very high- energy neutrino-induced events which have deposited energies from 5×10^{5} GeV to above 10^{11} GeV. Two neutrino-induced events with an estimated deposited energy of (2.6±0.3)×10^{6} GeV, the highest neutrino energy observed so far, and (7.7±2.0)×10^{5} GeV were detected. The atmospheric background-only hypothesis of detecting these events is rejected at 3.6σ. The hypothesis that the observed events are of cosmogenic origin is also rejected at >99% CL because of the limited deposited energy and the nonobservation of events at higher energy, while their observation is consistent with an astrophysical origin. Our limits on cosmogenic neutrino fluxes disfavor the UHECR sources having a cosmological evolution stronger than the star formation rate, e.g., active galactic nuclei and γ-ray bursts, assuming proton-dominated UHECRs. Constraints on UHECR sources including mixed and heavy UHECR compositions are obtained for models of neutrino production within UHECR sources. Our limit disfavors a significant part of parameter space for active galactic nuclei and new-born pulsar models. These limits on the ultrahigh-energy neutrino flux models are the most stringent to date.
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[A case of vasovagal syncope treatedwith pacemaker with rate-drop response]. ZHONGHUA XIN XUE GUAN BING ZA ZHI 2016; 44:891-893. [PMID: 27903377 DOI: 10.3760/cma.j.issn.0253-3758.2016.10.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
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Searches for Sterile Neutrinos with the IceCube Detector. PHYSICAL REVIEW LETTERS 2016; 117:071801. [PMID: 27563950 DOI: 10.1103/physrevlett.117.071801] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Indexed: 06/06/2023]
Abstract
The IceCube neutrino telescope at the South Pole has measured the atmospheric muon neutrino spectrum as a function of zenith angle and energy in the approximate 320 GeV to 20 TeV range, to search for the oscillation signatures of light sterile neutrinos. No evidence for anomalous ν_{μ} or ν[over ¯]_{μ} disappearance is observed in either of two independently developed analyses, each using one year of atmospheric neutrino data. New exclusion limits are placed on the parameter space of the 3+1 model, in which muon antineutrinos experience a strong Mikheyev-Smirnov-Wolfenstein-resonant oscillation. The exclusion limits extend to sin^{2}2θ_{24}≤0.02 at Δm^{2}∼0.3 eV^{2} at the 90% confidence level. The allowed region from global analysis of appearance experiments, including LSND and MiniBooNE, is excluded at approximately the 99% confidence level for the global best-fit value of |U_{e4}|^{2}.
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Lasing from organic quasicrystal fabricated by seven- and nine-beam interference. OPTICS EXPRESS 2016; 24:12330-12335. [PMID: 27410148 DOI: 10.1364/oe.24.012330] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We demonstrate mirrorless lasers based on all organic nanostructure fabricated by seven- and nine-beam interference using low contrast material, holographic polymer dispersed liquid crystals (H-PDLC). A finite-difference time-domain (FDTD) simulation is used to study the transmission of quasicrystal. The wavelengths of lasing peak are determined by both of local structure of quasicrystal that the pumping light experienced as well as the photoluminescence of laser dye doped. Features of mirrorless laser from quasicrystal based on H-PDLC include directional light source, low threshold, simple fabrication process, low cost and tunability. These properties make H-PDLC photonic quasicrystal promising for a new type of all organic miniature lasers.
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Low voltage polymer-stabilized blue phase liquid crystal reflective display by doping ferroelectric nanoparticles. OPTICS EXPRESS 2015; 23:32267-32273. [PMID: 26699017 DOI: 10.1364/oe.23.032267] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Low driving voltage is achieved in full color reflective display based on polymer-stabilized blue phase liquid crystal (PS-PBLC), by doping a small amount of ferroelectric nanoparticles. Both reflectance spectra of PS-PBLC with and without BaTiO₃ ferroelectric nanoparticles are studied under different applied external voltages. Superior to PS-PBLC without ferroelectric nanoparticles, the vertical driving electric fields of PS-PBLC with 0.4 wt.% BaTiO₃ ferroelectric nanoparticles are dramatically reduced by more than 70% for red, green and blue cells. The proposed approach would accelerate the practical application of full color PS-BPLC reflective display.
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Evidence for Astrophysical Muon Neutrinos from the Northern Sky with IceCube. PHYSICAL REVIEW LETTERS 2015; 115:081102. [PMID: 26340177 DOI: 10.1103/physrevlett.115.081102] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Indexed: 05/16/2023]
Abstract
Results from the IceCube Neutrino Observatory have recently provided compelling evidence for the existence of a high energy astrophysical neutrino flux utilizing a dominantly Southern Hemisphere data set consisting primarily of ν(e) and ν(τ) charged-current and neutral-current (cascade) neutrino interactions. In the analysis presented here, a data sample of approximately 35,000 muon neutrinos from the Northern sky is extracted from data taken during 659.5 days of live time recorded between May 2010 and May 2012. While this sample is composed primarily of neutrinos produced by cosmic ray interactions in Earth's atmosphere, the highest energy events are inconsistent with a hypothesis of solely terrestrial origin at 3.7σ significance. These neutrinos can, however, be explained by an astrophysical flux per neutrino flavor at a level of Φ(E(ν))=9.9(-3.4)(+3.9)×10(-19) GeV(-1) cm(-2) sr(-1) s(-1)(E(ν)/100 TeV(-2), consistent with IceCube's Southern-Hemisphere-dominated result. Additionally, a fit for an astrophysical flux with an arbitrary spectral index is performed. We find a spectral index of 2.2(-0.2)(+0.2), which is also in good agreement with the Southern Hemisphere result.
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Neuroprotective Effect of Insulin-like Growth Factor-II on 1- Methyl-4-Phenyl Pyridinium-Induced Oxidative Damage in Cortical Neuronal Cells. TROP J PHARM RES 2015. [DOI: 10.4314/tjpr.v14i7.10] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Flavor Ratio of Astrophysical Neutrinos above 35 TeV in IceCube. PHYSICAL REVIEW LETTERS 2015; 114:171102. [PMID: 25978221 DOI: 10.1103/physrevlett.114.171102] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Indexed: 06/04/2023]
Abstract
A diffuse flux of astrophysical neutrinos above 100 TeV has been observed at the IceCube Neutrino Observatory. Here we extend this analysis to probe the astrophysical flux down to 35 TeV and analyze its flavor composition by classifying events as showers or tracks. Taking advantage of lower atmospheric backgrounds for showerlike events, we obtain a shower-biased sample containing 129 showers and 8 tracks collected in three years from 2010 to 2013. We demonstrate consistency with the (fe:fμ:fτ)⊕≈(1:1:1)⊕ flavor ratio at Earth commonly expected from the averaged oscillations of neutrinos produced by pion decay in distant astrophysical sources. Limits are placed on nonstandard flavor compositions that cannot be produced by averaged neutrino oscillations but could arise in exotic physics scenarios. A maximally tracklike composition of (0:1:0)⊕ is excluded at 3.3σ, and a purely showerlike composition of (1:0:0)⊕ is excluded at 2.3σ.
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Influence of temperature on nucleus degradation of 4-androstene-3, 17-dione in phytosterol biotransformation by Mycobacterium sp. Lett Appl Microbiol 2015; 61:63-8. [PMID: 25868395 DOI: 10.1111/lam.12428] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Revised: 03/27/2015] [Accepted: 04/04/2015] [Indexed: 01/18/2023]
Abstract
UNLABELLED One of the steroid intermediates, 4-androstene-3, 17-dione (AD), in the biotransformation of phytosterols is valuable for the production of steroid medicaments. However, its degradation during the conversion process is one of the main obstacles to obtain high yields. In this study, the effect of temperature on nucleus degradation during microbial biotransformation of phytosterol was investigated. The results indicated that microbial degradation of phytosterol followed the AD-ADD-'9-OH-ADD' pathway, and that two important reactions involved in nucleus degradation, conversions of AD to ADD and ADD to 9-OH-ADD, were inhibited at 37°C. With a change in the culture temperature from 30 to 37°C, nucleus degradation was reduced from 39·9% to 17·6%, due to inhibition of the putative KstD and Ksh. These results suggested a simple way to decrease the nucleus degradation in phytosterol biotransformation and a new perspective on the possibilities of modifying the metabolism of strains used in industrial applications. SIGNIFICANCE AND IMPACT OF THE STUDY Nucleus degradation of products is one of the main problems encountered during phytosterol biotransformation. To solve this problem, the effect of temperature on nucleus degradation was investigated in the industrial production of steroid intermediates. The results are also helpful to the genetic modification of sterol-producing strains.
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Observation of high-energy astrophysical neutrinos in three years of IceCube data. PHYSICAL REVIEW LETTERS 2014; 113:101101. [PMID: 25238345 DOI: 10.1103/physrevlett.113.101101] [Citation(s) in RCA: 150] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Indexed: 06/03/2023]
Abstract
A search for high-energy neutrinos interacting within the IceCube detector between 2010 and 2012 provided the first evidence for a high-energy neutrino flux of extraterrestrial origin. Results from an analysis using the same methods with a third year (2012-2013) of data from the complete IceCube detector are consistent with the previously reported astrophysical flux in the 100 TeV-PeV range at the level of 10(-8) GeV cm-2 s-1 sr-1 per flavor and reject a purely atmospheric explanation for the combined three-year data at 5.7σ. The data are consistent with expectations for equal fluxes of all three neutrino flavors and with isotropic arrival directions, suggesting either numerous or spatially extended sources. The three-year data set, with a live time of 988 days, contains a total of 37 neutrino candidate events with deposited energies ranging from 30 to 2000 TeV. The 2000-TeV event is the highest-energy neutrino interaction ever observed.
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Abstract
We report on results of an all-sky search for high-energy neutrino events interacting within the IceCube neutrino detector conducted between May 2010 and May 2012. The search follows up on the previous detection of two PeV neutrino events, with improved sensitivity and extended energy coverage down to about 30 TeV. Twenty-six additional events were observed, substantially more than expected from atmospheric backgrounds. Combined, both searches reject a purely atmospheric origin for the 28 events at the 4σ level. These 28 events, which include the highest energy neutrinos ever observed, have flavors, directions, and energies inconsistent with those expected from the atmospheric muon and neutrino backgrounds. These properties are, however, consistent with generic predictions for an additional component of extraterrestrial origin.
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41
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Measurement of atmospheric neutrino oscillations with IceCube. PHYSICAL REVIEW LETTERS 2013; 111:081801. [PMID: 24010427 DOI: 10.1103/physrevlett.111.081801] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Indexed: 06/02/2023]
Abstract
We present the first statistically significant detection of neutrino oscillations in the high-energy regime (>20 GeV) from an analysis of IceCube Neutrino Observatory data collected in 2010 and 2011. This measurement is made possible by the low-energy threshold of the DeepCore detector (~20 GeV) and benefits from the use of the IceCube detector as a veto against cosmic-ray-induced muon background. The oscillation signal was detected within a low-energy muon neutrino sample (20-100 GeV) extracted from data collected by DeepCore. A high-energy muon neutrino sample (100 GeV-10 TeV) was extracted from IceCube data to constrain systematic uncertainties. The disappearance of low-energy upward-going muon neutrinos was observed, and the nonoscillation hypothesis is rejected with more than 5σ significance. In a two-neutrino flavor formalism, our data are best described by the atmospheric neutrino oscillation parameters |Δm(32)(2)|=(2.3(-0.5)(+0.6))×10(-3) eV(2) and sin(2)(2θ(23))>0.93, and maximum mixing is favored.
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First observation of PeV-energy neutrinos with IceCube. PHYSICAL REVIEW LETTERS 2013; 111:021103. [PMID: 23889381 DOI: 10.1103/physrevlett.111.021103] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Indexed: 06/02/2023]
Abstract
We report on the observation of two neutrino-induced events which have an estimated deposited energy in the IceCube detector of 1.04±0.16 and 1.14±0.17 PeV, respectively, the highest neutrino energies observed so far. These events are consistent with fully contained particle showers induced by neutral-current ν(e,μ,τ) (ν(e,μ,τ)) or charged-current ν(e) (ν(e)) interactions within the IceCube detector. The events were discovered in a search for ultrahigh energy neutrinos using data corresponding to 615.9 days effective live time. The expected number of atmospheric background is 0.082±0.004(stat)(-0.057)(+0.041)(syst). The probability of observing two or more candidate events under the atmospheric background-only hypothesis is 2.9×10(-3) (2.8σ) taking into account the uncertainty on the expected number of background events. These two events could be a first indication of an astrophysical neutrino flux; the moderate significance, however, does not permit a definitive conclusion at this time.
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Measurement of the atmospheric νe flux in IceCube. PHYSICAL REVIEW LETTERS 2013; 110:151105. [PMID: 25167245 DOI: 10.1103/physrevlett.110.151105] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Revised: 03/14/2013] [Indexed: 06/03/2023]
Abstract
We report the first measurement of the atmospheric electron neutrino flux in the energy range between approximately 80 GeV and 6 TeV, using data recorded during the first year of operation of IceCube's DeepCore low-energy extension. Techniques to identify neutrinos interacting within the DeepCore volume and veto muons originating outside the detector are demonstrated. A sample of 1029 events is observed in 281 days of data, of which 496±66(stat)±88(syst) are estimated to be cascade events, including both electron neutrino and neutral current events. The rest of the sample includes residual backgrounds due to atmospheric muons and charged current interactions of atmospheric muon neutrinos. The flux of the atmospheric electron neutrinos is consistent with models of atmospheric neutrinos in this energy range. This constitutes the first observation of electron neutrinos and neutral current interactions in a very large volume neutrino telescope optimized for the TeV energy range.
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Search for dark matter annihilations in the sun with the 79-string IceCube detector. PHYSICAL REVIEW LETTERS 2013; 110:131302. [PMID: 23581307 DOI: 10.1103/physrevlett.110.131302] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Revised: 02/20/2013] [Indexed: 06/02/2023]
Abstract
We have performed a search for muon neutrinos from dark matter annihilation in the center of the Sun with the 79-string configuration of the IceCube neutrino telescope. For the first time, the DeepCore subarray is included in the analysis, lowering the energy threshold and extending the search to the austral summer. The 317 days of data collected between June 2010 and May 2011 are consistent with the expected background from atmospheric muons and neutrinos. Upper limits are set on the dark matter annihilation rate, with conversions to limits on spin-dependent and spin-independent scattering cross sections of weakly interacting massive particles (WIMPs) on protons, for WIMP masses in the range 20-5000 GeV/c2. These are the most stringent spin-dependent WIMP-proton cross section limits to date above 35 GeV/c2 for most WIMP models.
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Two years efficiency of lamivudine and adefovir dipivoxil combined therapy in chronic hepatitis B patients. EUROPEAN REVIEW FOR MEDICAL AND PHARMACOLOGICAL SCIENCES 2013; 17:636-643. [PMID: 23543447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
BACKGROUND Lamivudine (LAM) and adefovir (ADV) are widely used in most Asian countries, though monotherapy is associated with the occurrence of resistance. AIM To evaluate the efficiency of LAM and ADV combined treatment of chronic hepatitis B patients with compensated cirrhosis. PATIENTS AND METHODS 206 eligible Chinese patients were randomly assigned in a 1:1 ratio to receive either LAM or ADV for the first 24 weeks. According to virologic response at 24 weeks, the patients either continued to monotherapy or switched to combined therapy for 48 weeks. After 48 weeks, all patients received LAM and ADV combined therapy for 96 weeks. RESULTS Serum HBV DNA levels significantly decreased in patients with ADV or LAM monotherapy and continuously reduced after the combined therapy. Serum ALT normalized rate were 88.24% and 81.37% at week 48, and 95.74% and 87.36% at week 96 in ADV and LAM group respectively, comparing to 60.78% and 56.73% in ADV and LAM groups at baseline. The accumulated virological breakthrough rate at week 48 and 96 was significantly higher in LAM group. CONCLUSIONS Both combination strategies were resulted in the long term virological, biochemical improvement in Chinese chronic hepatitis B patients with compensated cirrhosis.
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The trade-off between safety and efficiency in hydraulic architecture in 31 woody species in a karst area. TREE PHYSIOLOGY 2011; 31:865-877. [PMID: 21865304 DOI: 10.1093/treephys/tpr076] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Karst topography is a special landscape shaped by the dissolution of one or more layers of soluble bedrock, usually carbonate rock such as limestone or dolomite. Due to subterranean drainage, overland flow, extraction of water by plants and evapotranspiration, there may be very limited surface water. The hydraulic architecture that plants use to adapt to karst topography is very interesting, but few systematic reports exist. The karst area in southwestern China is unique when compared with other karst areas at similar latitudes, because of its abundant precipitation, with rainfall concentrated in the growing season. In theory, resistance to water-stress-induced cavitation via air seeding should be accompanied by decreased pore hydraulic conductivity and stem hydraulic conductivity. However, evidence for such trade-offs across species is ambiguous. We measured the hydraulic structure and foliar stable carbon isotope ratios of 31 karst woody plants at three locations in Guizhou Province, China, to evaluate the functional coordination between resistance to cavitation and specific conductivity. We also applied phylogenetically independent contrast (PIC) analysis in situations where the inter-species correlations of functional traits may be biased on the potential similarity of closely related species. The average xylem tension measurement, at which 50% of hydraulic conductivity of the plants was lost (Ψ(50)), was only -1.27 MPa. Stem Ψ(50) was positively associated with specific conductance (K(s)) (P < 0.05) and leaf specific conductance (K(l)) (P < 0.05). However, the PIC correlation for both relationships was not statistically significant. δ(13)C was positively related to K(l) in both the traditional cross-species correlation analysis and the corresponding PIC correlations (P < 0.05). The Huber value (sapwood area:leaf area ratio) was negatively correlated with K(s) in both the traditional cross-species correlation and the corresponding PIC correlations (P < 0.01). The characteristics of hydraulic architecture measured in this study showed that karst plants in China are not highly cavitation-resistant species. This study also supports the idea that there may not be an evolutionary trade-off between resistance to cavitation and specific conductivity in woody plants. Whole-plant hydraulic adjustment may decouple the trade-off relationship between safety and efficiency at the branch level.
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Limits on neutrino emission from gamma-ray bursts with the 40 string IceCube detector. PHYSICAL REVIEW LETTERS 2011; 106:141101. [PMID: 21561178 DOI: 10.1103/physrevlett.106.141101] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2011] [Indexed: 05/30/2023]
Abstract
IceCube has become the first neutrino telescope with a sensitivity below the TeV neutrino flux predicted from gamma-ray bursts if gamma-ray bursts are responsible for the observed cosmic-ray flux above 10(18) eV. Two separate analyses using the half-complete IceCube detector, one a dedicated search for neutrinos from pγ interactions in the prompt phase of the gamma-ray burst fireball and the other a generic search for any neutrino emission from these sources over a wide range of energies and emission times, produced no evidence for neutrino emission, excluding prevailing models at 90% confidence.
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Extending the search for neutrino point sources with IceCube above the horizon. PHYSICAL REVIEW LETTERS 2009; 103:221102. [PMID: 20366087 DOI: 10.1103/physrevlett.103.221102] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2009] [Indexed: 05/29/2023]
Abstract
Point source searches with the IceCube neutrino telescope have been restricted to one hemisphere, due to the exclusive selection of upward going events as a way of rejecting the atmospheric muon background. We show that the region above the horizon can be included by suppressing the background through energy-sensitive cuts. This improves the sensitivity above PeV energies, previously not accessible for declinations of more than a few degrees below the horizon due to the absorption of neutrinos in Earth. We present results based on data collected with 22 strings of IceCube, extending its field of view and energy reach for point source searches. No significant excess above the atmospheric background is observed in a sky scan and in tests of source candidates. Upper limits are reported, which for the first time cover point sources in the southern sky up to EeV energies.
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Limits on a muon flux from neutralino annihilations in the sun with the IceCube 22-string detector. PHYSICAL REVIEW LETTERS 2009; 102:201302. [PMID: 19519015 DOI: 10.1103/physrevlett.102.201302] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2009] [Revised: 03/27/2009] [Indexed: 05/27/2023]
Abstract
A search for muon neutrinos from neutralino annihilations in the Sun has been performed with the IceCube 22-string neutrino detector using data collected in 104.3 days of live time in 2007. No excess over the expected atmospheric background has been observed. Upper limits have been obtained on the annihilation rate of captured neutralinos in the Sun and converted to limits on the weakly interacting massive particle (WIMP) proton cross sections for WIMP masses in the range 250-5000 GeV. These results are the most stringent limits to date on neutralino annihilation in the Sun.
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Molecular characterization and expression pattern of the porcine STARS, a striated muscle-specific expressed gene. Biochem Genet 2008; 46:644-51. [PMID: 18726684 DOI: 10.1007/s10528-008-9178-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2007] [Accepted: 05/10/2008] [Indexed: 11/24/2022]
Abstract
STARS (striated muscle activator of Rho signaling) promotes the nuclear localization of MRTFs and mediates SRF transcription, which provides a potential muscle-specific mechanism for linking changes in the actin cytoskeleton structure with muscle gene expression. In this study, the full-length cDNA of the porcine STARS was cloned. The open reading frame of this gene contains 1,155 bp and encodes a protein of 384 amino acids, which is 79, 73, and 77% identical with human, mouse, and rat STARS genes, respectively. RT-PCR revealed that STARS is specifically expressed in heart and skeletal muscles. STARS is also distinctly different in different muscle developmental stages. The result indicates that its expression increased gradually from 33 dpc (days postcoitum) to postnatal muscles, and peaked 28 days postnatal. The porcine STARS was mapped to SSC4p13 using the somatic cell hybrid panel and the radiation hybrid panel IMpRH (LOD score 11.98). The data show that STARS is closely linked to marker SW871. A T/G single nucleotide polymorphism in the coding sequence, detected as Bsh1236I PCR-RFLP, displays allele frequency differences in six pig breeds.
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