Structural signature and transition dynamics of Sb2Te3 melt upon fast cooling

Sb-centered defective octahedrons connect with each other via four-fold rings, a close link of the four-fold ring and defective octahedrons in amorphous Sb₂Te₃ has been revealed.

Observation of the Identical Rigidity Dependence of He, C, and O Cosmic Rays at High Rigidities by the Alpha Magnetic Spectrometer on the International Space Station

We report the observation of new properties of primary cosmic rays He, C, and O measured in the rigidity (momentum/charge) range 2 GV to 3 TV with 90×10^{6} helium, 8.4×10^{6} carbon, and 7.0×10^{6} oxygen nuclei collected by the Alpha Magnetic Spectrometer (AMS) during the first five years of operation. Above 60 GV, these three spectra have identical rigidity dependence. They all deviate from a single power law above 200 GV and harden in an identical way.

Concordance of haemoglobin A1c, blood pressure and C-reactive protein between children and their parents in Chinese households

BACKGROUND

China has the world's highest diabetes prevalence, which along with hypertension and inflammation continues to grow particularly among children. Little is known about the strength of the association of these cardiometabolic risk factors between parents and their children; thus, the potential of household-based strategies to reduce risk is unknown.

OBJECTIVES

The objective of the study is to examine the parent-child association for haemoglobin A1c (HbA1c), blood pressure (BP) and C-reactive protein (CRP) in a large, geographically diverse Chinese sample.

METHODS

In 940 parent-child pairs (children aged 7-17 years) who participated in the 2009 China Health and Nutrition Survey, we measured each individual's HbA1c and CRP using fasting blood and BP. We used sex-specific random-effects linear regression to examine the parent-child association for these risk factors, accounting for within-family clustering.

RESULTS

Child's HbA1c was positively associated with parental HbA1c. Beta coefficients ranged from 0.06 (95% CI 0.03-0.12) for father-daughter to 0.43 (95% CI 0.28-0.58) for mother-son pairs. We also detected a positive mother-daughter association for BP and positive father-child associations for CRP.

CONCLUSION

The statistically significant parent-child association for HbA1c, BP and CRP in Chinese families suggests that household-based interventions could be useful for confronting the high rates of diabetes, hypertension and inflammation in China.

3D Pseudocontinuous Arterial Spin-Labeling MR Imaging in the Preoperative Evaluation of Gliomas

BACKGROUND AND PURPOSE

Previous studies showed conflicting results concerning the value of CBF maps obtained from arterial spin-labeling MR imaging in grading gliomas. This study was performed to investigate the effectiveness of CBF maps derived from 3D pseudocontinuous arterial spin-labeling in preoperatively assessing the grade, cellular proliferation, and prognosis of gliomas.

MATERIALS AND METHODS

Fifty-eight patients with pathologically confirmed gliomas underwent preoperative 3D pseudocontinuous arterial spin-labeling. The receiver operating characteristic curves for parameters to distinguish high-grade gliomas from low-grade gliomas were generated. Pearson correlation analysis was used to assess the correlation among parameters. Survival analysis was conducted with Cox regression.

RESULTS

Both maximum CBF and maximum relative CBF were significantly higher in high-grade gliomas than in low-grade gliomas (P < .001). The areas under the curve for maximum CBF and maximum relative CBF in distinguishing high-grade gliomas from low-grade gliomas were 0.828 and 0.863, respectively. Both maximum CBF and maximum relative CBF had no correlation with the Ki-67 index in all subjects and had a moderate negative correlation with the Ki-67 index in glioblastomas (r = -0.475, -0.534, respectively). After adjustment for age, a higher maximum CBF (P = .008) and higher maximum relative CBF (P = .005) were associated with worse progression-free survival in gliomas, while a higher maximum relative CBF (P = .033) was associated with better overall survival in glioblastomas.

CONCLUSIONS

3D pseudocontinuous arterial spin-labeling-derived CBF maps are effective in preoperative evaluation of gliomas. Although gliomas with a higher blood flow are more malignant, glioblastomas with a lower blood flow are likely to be more aggressive.

Differentiation of prostate cancer lesions in the Transition Zone by diffusion-weighted MRI

Objective

To differentiate prostate cancer lesions in transition zone by diffusion-weighted-MRI (DW-MRI).

Methods

Data from a total of 63 patients who underwent preoperative DWI (b of 0–1000 s/mm²) were prospectively collected and processed by a monoexponential (DWI) model and compared with a biexponential (IVIM) model for quantitation of apparent diffusion coefficients (ADCs), perfusion fraction f, diffusivity D and pseudo-diffusivity D*. Histogram analyses were performed by outlining entire-tumor regions of interest (ROIs). These parameters (separately and combined in a logistic regression model) were used to differentiate lesions depending on histopathological analysis of Magnetic Resonance/transrectal Ultrasound (MR/TRUS) fusion-guided biopsy. The diagnostic ability of differentiate the PCa from BHP in TZ was analyzed by ROC regression. Histogram analysis of quantitative parameters and Gleason score were assessed with Spearman correlation.

Results

Thirty (30 foci) cases of PCa in PZ and 33 (36 foci) cases of BPH were confirmed by pathology. Mean ADC, median ADC, 10th percentile ADC, 90th percentile ADC, kurtosis and skewness of ADC and mean D values, median D and 90th percentile D differed significantly between PCa and BHP in TZ. The highest classification accuracy was achieved by the mean ADC (0.841) and mean D (0.809). A logistic regression model based on mean ADC and mean D led to an AUC of 0.873, however, the difference is not significant. There were 7 Gleason 6 areas, 9 Gleason 7 areas, 8 Gleason 8 areas, 5 Gleason 9 areas and 2 Gleason 10 areas detected from the 31 prostate cancer areas, the mean Gleason value was(7.5 ± 1.2). The mean ADC and mean D had correlation with Gleason score(r = −0.522 and r = −0.407 respectively, P < 0.05).

Conclusion

The diagnosis efficiency of IVIM parameters was not superior to ADC in the diagnosis of PCa in TZ. Moreover, the combination of mean ADC and mean D did not perform better than the parameters alone significantly; It is feasible to stratify the pathological grade of prostate cancer by mean ADC.

Natural occurrence of deoxynivalenol and deoxynivalenol-3-glucoside in various wheat cultivars grown in Jiangsu province, China

Deoxynivalenol (DON) is a major mycotoxin found in wheat infected with Fusarium fungi. DON can be converted by plant detoxification into a form of ‘masked mycotoxin’ termed deoxynivalenol-3-glucoside (DON-3G). To recommend appropriate wheat cultivars for planting in order to reduce DON contamination in Jiangsu province, where a traditional Fusarium head blight (FHB) epidemic area is located in the lower reaches of Yangtze-Huaihe, we evaluated the capacity of various wheat cultivars to transform DON into DON-3G under field conditions. We collected and evaluated samples from 11 major wheat cultivars grown in 63 experimental stations in Jiangsu province in 2015 and 2016. All samples were contaminated with DON, with an average concentration of 2,087±112 and 2,601±126 µg/kg in 2015 and 2016, respectively. DON-3G was detected in 425 (96%) and 405 (97%) samples in 2015 and 2016, with an average concentration of 545±28 and 819±44 µg/kg, respectively. The DON-3G/DON ratio ranged from 5 to 84% (average, 30%) in 2015 and from 0 to 71% (average, 31%) in 2016. DON levels were highly correlated with DON-3G concentrations (P<0.01), and the FHB resistance of the wheat cultivars was proportional to their capacity to convert DON to DON-3G. Importantly, region, cultivar, and region × cultivar interaction all significantly affected DON and DON-3G concentrations and DON-3G/DON ratios. In general, FHB-resistant cultivars, such as Sumai 188 and Ningmai 13, had lower levels of DON and DON-3G than the others. However, additional factors, including the growing region and environmental variables, were important for wheat management when other wheat cultivars were evaluated.

[Analysis of survival and treatment outcome of young patients with high-risk diffuse large B cell lymphoma]

Objective: To analyze clinical feature and treatment outcome of young patients with high-risk diffuse large B cell lymphoma. Methods: A total of 122 young patients with high-risk diffuse large B cell lymphoma who were treated in Third Hospital of Peking University during the period from January 2000 to April 2015 were retrospectively analyzed, and the clinical features, laboratory data were included in Kaplan-Meier and prognostic analysis. Results: In our center, the incidence of young high-risk DLBCL was 27.1% in all DLBCL patients, median age was 44.0 years, 99.2% patients belong to Ⅲ and Ⅳstage, 50% patients had more than two extranodal organs involvement, and the higher proliferation index(Ki-67≥80%) was present in 63.1% of patients, Immunohistochemistry showed that 36.7% patients in 30 cases were double-expressed DLBCL. The overall response rate(ORR) for the whole group was 79.4%, the complete response rate was 39.7% , the 3, 5-year progression free survival rate was 59.8% and 57.0%, the 3, 5-year overall survival rate was 63.5% and 57.8%, respectively. 44.3% patients were refractory-relapsed DLBCL. Rituximab can improve the survival of patients and 3-year overall survival rate was 75.2% vs 46.1%(P=0.001). High-dose chemotherapy was superior to CHOP regimen which 3-year overall survival rate was 84.6% vs 54.1%(P=0.006). Compared with chemotherapy group , auto-hematopoietic stem cell transplantation can improve prognosis of patients and 3-year overall survival rate was 93.4% vs 48.3%(P<0.001). The level of Ki-67, B symptom, ECOG score, the level of LDH, WBC and albumin, ESR level, anemia, rituximab therapy, initial regimens, ASCT, initial treatment outcome and refractory-relapsed were predictive of overall survival. Multivariate analysis indicated that albumin level(RR=5.462, P=0.019), initial treatment outcome(RR=34.863, P<0.001) and refractory-relapsed (RR=24.374, P<0.001)were independent prognostic risk factors. Conclusions: Young patients with high-risk DLBCL were highly aggressive in clinical and pathological features . Rituximab and high-dose regimens can improve the survival of patients.

Laparoscopic abdominoperineal excision with trans-abdominal individualized levator transection: interim analysis of a randomized controlled trial

AIM

Extralevator abdominoperineal excision (ELAPR) is challenging 'conventional' abdominoperineal excision (APR), yet the safety and efficacy of ELAPR is still under debate. We therefore developed a laparoscopic APR with trans-abdominal individualized levator transection (LAPR-TILT) approach and compared the outcome with a conventional laparoscopic APR (CLAPR).

METHOD

All eligible patients were entered a single-centre randomized controlled trial to compare CLAPR and LAPR-TILT. We assessed the first 185 patients, including operative findings, complications, histopathology and urogenital function.

RESULTS

Ninety-three patients in the CLAPR group and 92 patients in the APR-TILT group were included for analysis. The APR-TILT procedure took less time [137 (101-175) min vs 146 (102-187) min; P = 0.03], mainly owing to faster perineal dissection. APR-TILT resulted in a reduced rate of bowel perforation (1.1% vs 8.6%; P = 0.04), circumferential resection margin positivity (1.1% vs 10.8%; P = 0.01) and postoperative wound complications (5.4% vs 16.2%; P = 0.02) compared with the CLAPR procedure. At a median follow-up of 19 months after surgery, three patients (3.2%) in the CLAPR group had tumour recurrence while no tumour recurrence occurred in the LAPR-TILT group. Patients who underwent LAPR-TILT reported fewer urinary or sexual problems (LAPR-TILT vs CLAPR, 10.9% vs 24.7% and 17.4% vs 38.7%, respectively).

CONCLUSION

Compared with CLAPR, LAPR-TILT achieved better pathological results for factors that are surrogate parameters for local recurrence. LAPR-TILT could also reduce the risk of urogenital dysfunction.

Effectiveness of home blood pressure telemonitoring: a systematic review and meta-analysis of randomised controlled studies

To summarise evidence about the effectiveness of home blood pressure telemonitoring (HBPT) and identify the key components of intervention. We comprehensively searched PubMed, EMBASE and the Cochrane Library for relevant studies. The authors were contacted for additional information. Two authors independently extracted the data and assessed the risk of bias. 46 randomised controlled trials including a total of 13 875 cases were identified. Compared with usual care, HBPT improved office systolic blood pressure (BP) and diastolic BP by 3.99 mm Hg (95% confidence interval (CI): 5.06-2.93; P<0.001) and 1.99 mm Hg (95% CI: -2.60 to -1.39; P<0.001), respectively. A larger proportion of patients achieved BP normalisation in the intervention group (relative risk (RR): 1.16; 95% CI: 1.08-1.25; P<0.001). For HBPT plus additional support (including counselling, education, behavioural management, medication management with decision, adherence contracts and so on) versus HBPT alone (or plus less intense additional support), the mean changes in systolic and diastolic BP were 2.44 mm Hg (95% Cl, 4.88 to 0.00 mm Hg; P=0.05) and 1.12 mm Hg (95% CI, -2.34 to 0.1 mm Hg; P=0.07), respectively. For those surrogate outcomes, low-strength evidence failed to show difference. In subgroup analysis, high strength evidence supported a lower BP with HBPT that lasted for 6 or 12 months and was accompanied with counselling support from study personnel. HBPT can improve BP control in the hypertensive patients. It may be more efficacious when a proactive additional support is provided during the intervention process.

An adaptive Fuzzy C-means method utilizing neighboring information for breast tumor segmentation in ultrasound images

PURPOSE

Ultrasound (US) imaging has been widely used in breast tumor diagnosis and treatment intervention. Automatic delineation of the tumor is a crucial first step, especially for the computer-aided diagnosis (CAD) and US-guided breast procedure. However, the intrinsic properties of US images such as low contrast and blurry boundaries pose challenges to the automatic segmentation of the breast tumor. Therefore, the purpose of this study is to propose a segmentation algorithm that can contour the breast tumor in US images.

METHODS

To utilize the neighbor information of each pixel, a Hausdorff distance based fuzzy c-means (FCM) method was adopted. The size of the neighbor region was adaptively updated by comparing the mutual information between them. The objective function of the clustering process was updated by a combination of Euclid distance and the adaptively calculated Hausdorff distance. Segmentation results were evaluated by comparing with three experts' manual segmentations. The results were also compared with a kernel-induced distance based FCM with spatial constraints, the method without adaptive region selection, and conventional FCM.

RESULTS

Results from segmenting 30 patient images showed the adaptive method had a value of sensitivity, specificity, Jaccard similarity, and Dice coefficient of 93.60 ± 5.33%, 97.83 ± 2.17%, 86.38 ± 5.80%, and 92.58 ± 3.68%, respectively. The region-based metrics of average symmetric surface distance (ASSD), root mean square symmetric distance (RMSD), and maximum symmetric surface distance (MSSD) were 0.03 ± 0.04 mm, 0.04 ± 0.03 mm, and 1.18 ± 1.01 mm, respectively. All the metrics except sensitivity were better than that of the non-adaptive algorithm and the conventional FCM. Only three region-based metrics were better than that of the kernel-induced distance based FCM with spatial constraints.

CONCLUSION

Inclusion of the pixel neighbor information adaptively in segmenting US images improved the segmentation performance. The results demonstrate the potential application of the method in breast tumor CAD and other US-guided procedures.

Measuring Endotracheal Tube Depth by Bedside Ultrasound in Adult Patients in an Intensive Care Unit: A Pilot Study

The aim of the study described here was to evaluate the feasibility and accuracy of measuring endotracheal tube (ETT) depth with ultrasound in adult patients in an intensive care unit (ICU). The distance between the upper margin of the cuff and the upper margin of the aortic arch (Duc-ua) of 67 ICU patients was measured by ultrasound, and the time of measurement was recorded. The level of agreement between the distance between the tip of the ETT and the carina (Dtt-c) measured by ultrasound (U-Dtt-c) and Dtt-c measured by bronchoscopy (B-Dtt-c) was assessed using linear regression and a Bland-Altman plot. There was a significant correlation between B-Dtt-c and U-Dtt-c (r = 0.844, p < 0.001). Also, the Bland-Altman plot revealed strong agreement between B-Dtt-c and U-Dtt-c. The time it took to measure ETT depth by ultrasound was 33.91 ± 5.43 s. In conclusion, bedside ultrasound provides a novel and convenient method for measuring the depth of ETT in ICU patients.

[Survival analysis of surgically treated renal cell carcinoma: an analysis of 10-year data from single center]

OBJECTIVE

To explore how clinical features of renal cell carcinoma (RCC) relate to cancer patients' prognosis and survival.

METHODS

A total of 1 497 renal cell carcinoma patients received surgical treatments in Department of Urology, Peking Union Medical College were admitted between January 2002 and December 2012. Telephone interviews and complimentary medical records review were carried out to acquire follow-up data, including post-surgery adjuvant therapy, disease progression and survival.

RESULTS

There were 1 326 of all 1 497 RCC cases successfully followed up, including 899 male and 427 female cases. The median age was 54(18) years (M(QR)). There were 1 049 T1 cases (79.11%), 139 T2 cases (10.48%), 125 T3 cases (9.43%), and 13 T4 cases (0.98%). As for types of surgery, there were 584 (44.04%) nephron-sparing surgery cases, and 742 (55.96%) radical nephrectomy cases. As for pathological subtypes, it included 1 153 (86.95%) clear cell renal cell carcinoma cases, and 173 (13.05%) non-clear cell renal cell carcinoma cases. Median length of follow-up was 43.6 months. During follow-up, 147 patients developed RCC related progression, with a median progression free survival of 18.2 months.Sixty-four patients died from RCC related progression, with a median cancer specific survival (CSS) of 27.7 months. RESULTS of data analysis showed that CSS rates of 1-, 5-, 10-year of T1 stage post-surgical RCC were 99.61%, 97.24%, 92.08%, respectively; CSS rates of 1-, 5-, 10-year of T2 stage were 98.51%, 92.01%, 85.08%, respectively; and CSS rates of 1-, 5-, 10-year of T3-4 stage were 92.40%, 77.99%, 42.56%, respectively. Multivariable Cox regression analysis showed that signs of lung metastasis, signs of bone metastasis, tumor N stage, pathological subtype, microscopic sarcomatoid changing, and types of progression were major risk factors for RCC cancer specific survival (P<0.05).

CONCLUSIONS

Surgery is the primary choice of treatment in RCC. The survival is not same with different T stage. T stage affects the progression of renal cell carcinoma. N stage, lung and bone symptoms, pathological type, sarcomatoid changes and postoperative metastasis of renal cell carcinoma will affect the mortality of patients.

Structure similarity-guided image binarization for automatic segmentation of epidermis surface microstructure images

Partitioning epidermis surface microstructure (ESM) images into skin ridge and skin furrow regions is an important preprocessing step before quantitative analyses on ESM images. Binarization segmentation is a potential technique for partitioning ESM images because of its computational simplicity and ease of implementation. However, even for some state-of-the-art binarization methods, it remains a challenge to automatically segment ESM images, because the grey-level histograms of ESM images have no obvious external features to guide automatic assessment of appropriate thresholds. Inspired by human visual perceptual functions of structural feature extraction and comparison, we propose a structure similarity-guided image binarization method. The proposed method seeks for the binary image that best approximates the input ESM image in terms of structural features. The proposed method is validated by comparing it with two recently developed automatic binarization techniques as well as a manual binarization method on 20 synthetic noisy images and 30 ESM images. The experimental results show: (1) the proposed method possesses self-adaption ability to cope with different images with same grey-level histogram; (2) compared to two automatic binarization techniques, the proposed method significantly improves average accuracy in segmenting ESM images with an acceptable decrease in computational efficiency; (3) and the proposed method is applicable for segmenting practical EMS images. (Matlab code of the proposed method can be obtained by contacting with the corresponding author.).

Si-centered capped trigonal prism ordering in liquid Pd82Si18 alloy study by first-principles calculations

Distribution of trigonal prism capped with three half-octahedra (orange clusters), archimedean anti-prism (green ones) and icosahedron (blue ones) clusters in Pd₈₂Si₁₈ at different temperature (a) 900 K, (b) 1216 K. (c) Connection way of different clusters, and pink ones are the sharing atoms.

The influence of emission control on particle number size distribution and new particle formation during China's V-Day parade in 2015

Temporary strict emission control strategies were conducted to ensure good air quality for China's V-Day parade (August 20-September 3, 2015) in Beijing and nearby cities. The influence of the emission control on particle number size distribution (PNSD) was evaluated based on the long-term measurements of PNSD at a rural site (Shangdianzi) located northeast of Beijing. This study also presented the comparison results of PNSD during the parade in 2015 and the Olympics in 2008 (August 8-23), as well as the same period without strict emission control in 2010-2013 (August 20-September 3). Compared with the same period in 2010-2013 and 2008 Olympics, the accumulation mode particle number concentration showed a significant reduction in 2015, and the PM₁ mass concentration decreased by approximately 60-90%. The alleviation of the PM₁ was also associated with the weather conditions. The back trajectories analysis results showed that the southerly air mass passing through the polluted areas accounted for 14% of the total back trajectories in 2015, which contributed to approximately 60% in the other years. During the control period in 2015, there were six new particle formation (NPF) events observed, with a higher frequency, but a lower formation rate and growth rate than the same period in 2010-2013. The comparison of the condensation sink (CS), sulfuric acid, solar radiation and relative humidity among the different years indicated that at Shangdianzi station, the first factor in determining the NPF occurrence was the CS, and the second factor could be the concentration level of precursor vapors participating in the NPF event (e.g., sulfuric acid).

Precision Measurement of the Boron to Carbon Flux Ratio in Cosmic Rays from 1.9 GV to 2.6 TV with the Alpha Magnetic Spectrometer on the International Space Station

Knowledge of the rigidity dependence of the boron to carbon flux ratio (B/C) is important in understanding the propagation of cosmic rays. The precise measurement of the B/C ratio from 1.9 GV to 2.6 TV, based on 2.3 million boron and 8.3 million carbon nuclei collected by AMS during the first 5 years of operation, is presented. The detailed variation with rigidity of the B/C spectral index is reported for the first time. The B/C ratio does not show any significant structures in contrast to many cosmic ray models that require such structures at high rigidities. Remarkably, above 65 GV, the B/C ratio is well described by a single power law R^{Δ} with index Δ=-0.333±0.014(fit)±0.005(syst), in good agreement with the Kolmogorov theory of turbulence which predicts Δ=-1/3 asymptotically.

Loss of Dnmt3b accelerates MLL-AF9 leukemia progression

Acute myeloid leukemia (AML) is a heterogeneous hematopoietic disorder with a poor prognosis. Abnormal DNA methylation is involved in the initiation and progression of AML. The de novo methyltransferases Dnmt3a and Dnmt3b are responsible for the generation of genomic methylation patterns. While DNMT3A is frequently mutated in hematological malignancies, DNMT3B is rarely mutated. Although it has been previously reported that Dnmt3b functions as a tumor suppressor in a mouse model of Myc-induced lymphomagenesis, its function in AML is yet to be determined. In this study, we demonstrated that deletion of Dnmt3b accelerated the progression of MLL-AF9 leukemia by increasing stemness and enhancing cell cycle progression. Gene profiling analysis revealed upregulation of the oncogenic gene set and downregulation of the cell differentiation gene set. Furthermore, loss of Dnmt3b was able to synergize with Dnmt3a deficiency in leukemia development. Taken together, these results demonstrate that Dnmt3b plays a tumor suppressive role in MLL-AF9 AML progression, thereby providing new insights into the roles of DNA methylation in leukemia development.

[QuEChERS pretreatment method for determination of organophosphate pesticide and raticide in whole blood]

Objective: To investigate the QuEChERS pretreatment method combined with on-line gel permeation chromatography-gas chromatography/mass spectrometry (GPC-GC/MS) for the determination of organophosphate pesticide and raticide in whole blood. Methods: The samples were pretreated with QuEChERS. A total of 1 ml acetonitrile was added to 1 ml whole blood sample for extraction, and 0.5 g sodium chloride was added. The mixture was oscillated for 15 seconds at a temperature of 4° C and centrifuged at a high speed of 12 000 r/min for 10 minutes. The supernatant was transferred to a centrifuge tube, the dispersive absorbent was used to remove the interfering matrix, and then GPC-GC/MS was used for analysis. Results: Organophosphate pesticide and raticide had a good linear relationship within the range of 0.1~0.5 mg/L, and the correlation coefficient was 0.997 7~1.000 0. The limit of quantitation of this method was 0.005~0.050 mg/L, and the recovery rate was 43.11%~106.68%, and the relative standard deviation of most drugs was <10%. Conclusion: The pretreatment method is simple, time-saving, and highly automated and has the features of low detection limit, high accuracy, and good accuracy. It can meet the requirements of rapid and accurate screening of organophosphate pesticides and raticide.

[A preliminary study for the effect of nano hydroxyapatite on human adipose-derived mesenchymal stem cells mixture 3D bio-printing]

OBJECTIVE

To study the effect of nano hydroxyapatite on human adipose-derived mesenchymal stem cells(hASCs) mixture 3D bio-printing for cells' proliferation and osteogenesis.

METHODS

P5 hASCs were used as seed cells, 10 g/L nano hydroxyapatite was added into the cell-sodium alginate-gelatin mixture (concentration: 20 g/L sodium alginate, 80 g/L gelatin; cell density: 1×106/mL), then the mixture was printed by 3D bio-printer as the experimental group. And the cell-sodium alginate-gelatin mixture without nano hydroxyapatite was printed as the control group. Respectively, both the experimental and control groups were detected by microscope, CCK-8, Western blot and PCR at certain time pointsafter being printed, whose cells' proliferation and osteogenic differentiation were analyzed.

RESULTS

The microscopic observation and CCK-8 results showed that the cells of the experimental group and the control group both had a good proliferation 24 h and 7 d after being printed. The Western blot results showed that 14 d after printing, the expression of Runt-related transcription factor 2 (RUNX2) had no statistical difference between the experimental group and control group. The PCR results showed that 14 d after printing, the expression of osteogenesis-related genes (RUNX2, osterix, and osteocalcin) was significantly higher in the experimental group than in the control group.

CONCLUSION

Nano hydroxyapatite can increase osteogenic differentiation of the hASCs mixture after bio-printing, in which the cells still have a good proliferation.

DREADD in parvalbumin interneurons of the dentate gyrus modulates anxiety, social interaction and memory extinction

Parvalbumin (PV)-positive interneurons in the hippocampus play a critical role in animal memory, such as spatial working memory. However, how PV-positive interneurons in the subregions of the hippocampus affect animal behaviors remains poorly defined. Here, we achieved specific and reversible activation of PV-positive interneurons using designer receptors exclusively activated by designer drugs (DREADD) technology. Inducible DREADD expression was demonstrated in vitro in cultured neurons, in which co-transfection of the hM3D-Gq-mCherry vector with a Cre plasmid resulted in a cellular response to hM3Dq ligand clozapine-N-oxide (CNO) stimulation. In addition, the dentate gyrus (DG) of PV-Cre mice received bilateral injection of control lentivirus or lentivirus expressing double floxed hM3D-Gq-mCherry. Selective activation of PV-positive interneurons in the DG did not affect locomotor activity or depression-related behavior in mice. Interestingly, stimulation of PV-positive interneurons induced an anxiolytic effect. Activation of PVpositive interneurons appears to impair social interaction to novelty, but has no effect on social motivation. However, this defect is likely due to the anxiolytic effect as the exploratory behavior of mice expressing hM3DGq is significantly increased. Mice expressing hM3D-Gq did not affect novel object recognition. Activation of PV-positive interneurons in the DG maintains intact cued and contextual fear memory but facilitates fear extinction. Collectively, our results demonstrated that proper control of PV interneurons activity in the DG is critical for regulation of the anxiety, social interaction and fear extinction. These results improve our fundamental understanding of the physiological role of PV-positive interneurons in the hippocampus.

Effects of Oxygen Impurities on Glass-Formation Ability in Zr2Cu Alloy

Using ab initio molecular dynamics simulations, we show that oxygen (O) impurities have a noticeable influence on the glass-formation ability (GFA) in Zr2Cu alloy. Cu-centered icosahedral clusters and Zr-centered Kasper polyhedra are the dominate short-range orders in undercooled Zr2Cu liquid which are most likely to be responsible for the glass formation in Zr2Cu systems. When O is introduced, a Zr octahedron is formed around the O impurity. Most of the Zr atoms in the octahedron also serve as the bridging atoms for cross-linked Kasper polyhedral network, resulting in an O-centered medium range order (MRO) structure. Meanwhile, Cu atoms are moved away from the first shell of O-centered octahedral clusters. With 1 at. % O impurities, the fractions of Zr-centered clusters are less affected, while the increase of ideal icosahedral order and decrease of distorted icosahedral order lead to a more stable atomic structure. This result suggests that a low concentration of O impurities would improve the GFA in Zr2Cu alloy. However, when ∼5 at. % O impurities are included, the ideal icosahedral clusters and Zr-centered Kasper polyhedra are seriously suppressed by the formation of O-centered MRO, which can lead to deterioration of GFA. Our analyses provide useful insight into glass formation behavior in O-doped metallic alloy systems.

Antiproton Flux, Antiproton-to-Proton Flux Ratio, and Properties of Elementary Particle Fluxes in Primary Cosmic Rays Measured with the Alpha Magnetic Spectrometer on the International Space Station

A precision measurement by AMS of the antiproton flux and the antiproton-to-proton flux ratio in primary cosmic rays in the absolute rigidity range from 1 to 450 GV is presented based on 3.49×10^{5} antiproton events and 2.42×10^{9} proton events. The fluxes and flux ratios of charged elementary particles in cosmic rays are also presented. In the absolute rigidity range ∼60 to ∼500  GV, the antiproton p[over ¯], proton p, and positron e^{+} fluxes are found to have nearly identical rigidity dependence and the electron e^{-} flux exhibits a different rigidity dependence. Below 60 GV, the (p[over ¯]/p), (p[over ¯]/e^{+}), and (p/e^{+}) flux ratios each reaches a maximum. From ∼60 to ∼500  GV, the (p[over ¯]/p), (p[over ¯]/e^{+}), and (p/e^{+}) flux ratios show no rigidity dependence. These are new observations of the properties of elementary particles in the cosmos.