[Analysis of occupational pneumoconiosis in Jiangsu province from 2006 to 2017]

Objective: To analyze the characteristics and patterns of occupational pneumoconiosis in Jiangsu Province, China, from 2006 to 2017, and to provide a scientific basis for government departments to develop effective interventions and preventive strategies against occupational pneumoconiosis. Methods: The data of 9327 patients with occupational pneumoconiosis were retrieved from the online report of occupational pneumoconiosis in Jiangsu Province from 2006 to 2017. Excel worksheet and SPSS 20.0 software were used to organize and analyze the data, respectively. An epidemiological statistical analysis was performed on age of onset, length of dust exposure, type of work, industry category, type of pneumoconiosis, annual incidence of pneumoconiosis, regional distribution, enterprise scale, and economic category in those patients. Results: A total of 9 327 patients with occupational pneumoconiosis were reported in Jiangsu Province from 2006 to 2017. In those patients, 8 559 were newly diagnosed and 768 had advanced disease. The male-female ratio was 16.34:1.Patients with stage I pneumoconiosis(6 994, 74.99%) were dominant in all the patients. The mean age of onset and length of dust exposure were 58.5±10.7 and 15.3±10.9 years, respectively. Most of the patients (6 012, 64.46%) had an age of onset between 50 and 69 years. For the length of dust exposure, the highest percentage was observed in patients exposed for no more than 5 years (2 231, 23.92%).The largest number of patients diagnosed with pneumoconiosis(1 200, 12.87%) was reported in 2010. Most of the patients(7 012, 75.18%) were from four cities, i.e, Wuxi (2 090, 22.41%), Yancheng (1 987, 21.30%), Suzhou (1 552, 16.64%), and Xuzhou (1 383, 14.83%). In all the patients, the incidence of silicosis (6791, 72.81%) was highest, followed by coal worker pneumoconiosis (1 364, 14.62%) and electric welder pneumoconiosis (563, 6.04%).Pneumoconiosis complicated by tuberculosis was found in 28 (0.3%) patients.A total of 1616 (17.33%) patients were reported in health, social security, and social welfare industries, while 1474 (15.80%) patients worked for coal mining and washing. Rock drillers (2 818, 30.21%) were dominant in those patients.State-owned economic enterprises reported the largest number of patients(5 441, 58.34%).Patients from small enterprises (4 323, 46.35%) had the highest percentage. Conclusion: Pneumoconiosis is an occupational disease with a high incidence in Jiangsu Province. Pneumoconiosis patients show an industry- and job-centered distribution. The length of dust exposure is decreasing.

[The effect of hypothalamic-pituitary-thyroid axis hormone levels and depression in obstructive sleep apnea-hypopnea syndrome]

Objective: To explore the change of hypothalamic-pituitary-thyroid axis hormones and it's role in depression in obstructive sleep apnea-hypopnea syndrome. Methods: Seventy-three male OSAHS patients [age (39±11) years] and 13 male controls [age (36±7.5) years] were enrolled from August 2013 to May 2017 in the 1(st) Hospital of China Medical University. Overnight polysomnography and depression were assessed. The serum TRH, TSH, FT4 and FT3 levels were measured on the next morning. The relationship between depression and hypothalamic-pituitary-thyroid axis was analyzed. Results: Compared with the control group, severe hypoxia group had higher serum FT3 level [(4.5±0.6) ng/L vs. (5.4±0.7)ng/L, P<0.05)] and depression score (30±7 vs. 40±10, P<0.05). Further analysis revealed that serum FT3 level (5.0±0.5 ng/L vs. 5.5±0.7ng/L, P<0.05) and FT4 level [(16.2±1.9) ng/L vs. (18.2±2.3) ng/L, P<0.05] were lower in the patients with depression than those without. Conclusion: The decrease of serum FT3 and FT4 levels in OSAHS patients with severe hypoxia was closely related to the occurrence of depression.

[The influence of chronic intermittent hypoxia on hypothalamic-somatotropic axis in rats]

Objective: To investigate the effects of chronic intermittent hypoxia on somatotropic axis hormone levels in rats. Methods: Mature male Wistar rats were exposed to air or intermittent hypoxia randomly.The serum levels of growth hormone-releasing hormone (GHRH), growth hormone (GH) and somatostatin (SS) were measured before exposure, at the 4th, 8th, and 12th week after exposure. Different hormone levels in two groups were compared and analyzed. Results: Compared with the control group, GHRH levels in chronic intermittent hypoxic group showed a significant decline at the 4th week [(732.77±46.99)pg/ml vs. (893.59±40.00) pg/ml, P<0.05], while SS levels at the 8th week [(30.71±2.27) pg/ml vs. (44.69±3.36) pg/ml, P<0.05] and GH levels at the 12th week [(1.20±0.29) ng/ml vs. (2.06±0.13) ng/ml, P<0.05] were similarly reduced. As the duration of intermittent hypoxia was prolonged, the GHRH levels did not decrease further [4th week (732.77±46.99) pg/ml vs. 8th week (607.54±131.61) pg/ml vs. 12th week (730.05±40.63) pg/ml, P>0.05].However, the serum SS levels decreased further from the 8th week to the 12th week [(30.71±2.27) pg/ml vs. (24.41±4.06) pg/ml, P<0.05]. Conclusion: Chronic intermittent hypoxia might inhibit the function of somatotropic axis. Hypothalamic hormones are the earlyonesto be influenced, thereafter the entire axis.

[Collision tumor in the hypopharynx: a case report]

SummaryA collision tumor consists of two different histologically distinct and topographically independent tumors merging in the same mass. In the head and neck area, they are rare and only a few cases have been reported in the hypopharynx. It is difficult to choose to treat this disease.

[Efficacy and safety of active transfer of plaque versus provisional stenting with drug-eluting stents for the treatment of coronary bifurcation lesions]

Objective: To compare the efficacy and safety of active transfer of plaque (ATP) versus provisional stenting (PS) with drug-eluting stents (DES) for the treatment of coronary bifurcation lesions. Methods: A total of 1 136 patients with bifurcation lesions hospitalized in 6 selected hospitals between January 2010 and January 2014 were included in this prospective observational trial, patients were divided into either ATP (n=560) or PS group (n=576) accordingly. The primary endpoint was target lesion revascularization within 1 year, and the second endpoints were all-cause death, cardiogenic death, myocardial infarction, stent thrombosis, stroke, recurrent angina within 1 year. Results: There were no significant differences in age, sex, hypertension, diabetes, hyperlipidemia and smoking history between the two groups (P>0.05). The incidence of TIMI blood flow <3 grade in the side branch (1.6%(9/560) vs. 7.5% (43/576), P<0.01), acute occlusion of the side branch (1.3%(7/560) vs. 7.1%(41/576), P<0.01) and implanted stents of side branch (1.8%(10/560) vs. 7.8% (45/576), P<0.01) were significantly lower in the ATP group than those in the PS group. During the one year follow up, the rate of target lesion revascularization was similar between ATP group and PS group (4.6%(26/560) vs. 4.0%(23/576), P=0.66). Conclusions: The effectiveness and safetyof ATP techniquein the patients with coronary bifurcation lesions is comparable to the PS technique. However, ATP technique is superior to PS technique on effectively reducing the incidence of implanted stents in the side branch.

[Preliminary clinical outcomes of patients with acute myocardial infarction complicated with cardiogenic shock treated with PIE-2R model]

Objective: To investigate the clinical experience of application of PIE-2R model to treat patients with acute myocardial infarction (AMI) complicated with cardiogenic shock (CS). Methods: A total of 129 patients with AMI complicated with CS treated with PIE-2R model, featuring in respiratory management, pacemaker, mechanical circulatory support (MCS) and timely myocardial revascularization, admitted in Beijing Anzhen Hospital, Capital Medical University between January 2013 and December 2018, were consecutively enrolled. Patient's baseline characteristics, implementation of each component of PIE-2R model, and in-hospital mortality were analyzed. Results: Participants' average age was 60 years, and male patients accounted for 78%. In all enrolled patients, 61% were implanted with temporary pacemaker due to severe bradyarrhythmia, 73% were treated with mechanical ventilation because of acute respiratory failure or pulmonary edema, and all patients were treated with percutaneous coronary intervention (PCI) supported by MCS (85% of cases with intra-aortic balloon pump and 15% of cases with veno-arterial extracorporeal membrane oxygenation or Impella), with an average first medical contact to MCS time of 87 minutes, and 79% were treated with second-generation drug-eluting stent. Eventually, after emergency treatment using PIE-2R model, 69 patients survived and in-hospital mortality was 46.5%. Conclusion: The application of PIE-2R model in patients with acute myocardial infarction complicated with cardiogenic shock is feasible, with a lower in-hospital mortality.

Tests of General Relativity with GW170817

The recent discovery by Advanced LIGO and Advanced Virgo of a gravitational wave signal from a binary neutron star inspiral has enabled tests of general relativity (GR) with this new type of source. This source, for the first time, permits tests of strong-field dynamics of compact binaries in the presence of matter. In this Letter, we place constraints on the dipole radiation and possible deviations from GR in the post-Newtonian coefficients that govern the inspiral regime. Bounds on modified dispersion of gravitational waves are obtained; in combination with information from the observed electromagnetic counterpart we can also constrain effects due to large extra dimensions. Finally, the polarization content of the gravitational wave signal is studied. The results of all tests performed here show good agreement with GR.

[Epidemiological characteristics of pesticide poisoning in Xuzhou city from 2005 to 2017]

Objective: To understand the characteristics and causes of pesticide poisoning in Xuzhou city, and provide basis for formulating prevention and control measures. Methods: The cases of pesticide poisoning in Xuzhou City from 2005 to 2017 were collected from "Pesticide Poisoning Report Card" . The data were analyzed and assessed by EpiData. The SPSS 22.0 software was used for statistical analysis. Results: During the thirteen years, there were a total of 8092 cases of pesticide poisoning, among which, the number of occupational pesticide poisoning was 1 408, accounting for 17.4% of the total number of cases, 14 patients died, the case fatality rate was 0.1%. There were 2, 992 cases of male poisoning, accounting for 36.97% of the total number of cases, and 5, 100 cases of female poisoning, accounting for 63.03%. There were 6684 non-productive pesticide poisonings, accounting for 82.6% of the total number of cases; 387 deaths occurred, and the mortality rate was 5.8%. Among non-productive poisonings, the incidence of oral pesticide poisoning was 84.3%, and the incidence of accidental poisoning by pesticides was 15.7%. Organophosphorus pesticides poisoning cases accounted for the majority of oral pesticide poisoning cases. The overall incidence of pesticide poisoning showed a downward trend. The age of non-productive pesticide poisoning cases was mainly 15-44 years old, and the number of cases of poisoning were 4 029 cases (60.28%) . With the increase of age, the mortality rate of poisoning cases was higher, especially for those over 60 years old who died of oral pesticide poisoning (40.1%) . The peak of pesticide poisoning began to increase in the second quarter and reached its peak in the third quarter. Conclusion: Although the cases of pesticide poisoning reported in Xuzhou City have been declining in recent years, the situation is still severe. The proportion of oral pesticide suicide accounts for a large proportion, and the mortality rate of elderly and female is relatively high, and the government should pay more attention. Workers should conduct safety education and psychological counseling to improve the knowledge and consciousness of safe use of pesticides.

Ultrastructure of duck Tembusu virus observed by electron microscopy with negative staining

Duck Tembusu virus (DTMUV) is a newly emerging enveloped flavivirus. This study shows the ultrastructure of DTMUV using viral purification, negative staining and electron microscopy. Electron microscopic examinations revealed mature DTMUV particles with 50 to 75 nm in diameter and typical enveloped flavivirus structure that consists of the internal nucleocapsid, an inner layer of lipid bilayer and an external layer of E glycoprotein ectodomain. Particles appear to be mostly spherical. In particular, RNA core is deep colored and dense, both capsid and lipid bilayer are clearly visible, the capsid forms regular hexagon, and E glycoprotein ectodomain forms a fringe instead of visible spikes. Thus, this report about the clear ultrastructure of the DTMUV particles will be the major driving forces behind structural biology of DTMUV.

[Analysis of occupational poisoning in Jiangsu Province, from 2006-2015]

Objective: Analysis of occupational poisoning character and laws in Jiangsu Province from 2006-2015, so as to provide scientific basis for the formulation of effective intervention measures and prevention strategies. Methods: According to the data of Jiangsu province occupational poisoning cases reports of year 2006 to 2015, by EXCEL arranged, using SPSS software to do epidemiological data statistical analysis. Results: In the past ten years, the number of occupational poisoning cases reported in Jiangsu province increased first and then declined. 547 cases of acute occupational poisoning reported in Jiangsu province from 2006-2015 years (35.82% of the total poisoning cases, the same below) , 980 cases of chronic occupational poisoning (64.18%) . The ratio of male and female in acute poisoning was 2.48, while 1.55 of chronic poisoning. The cases of poisoning reported were young and middle-aged, and working years was mainly in 5 years. The cases reported in the south of Jiangsu (mainly is chronic poisoning) is higher than that in the northern part of Jiangsu (mainly is acute poisoning) , which is more economically underdeveloped.. The reported highest mortality rate of occupational poisoning is asphyxia gas poisoning (5.43%) , followed by irritating gas poisoning (2.99%) and organic solvent poisoning (0.47%) . Many more occupational poisoning cases reported from large, joint-stock enterprises, especially chronic poisoning. Meanwhile more cases of acute poisoning reported from small, micro private enterprises. Conclusion: Although a decline in occupational poisoning cases in Jiangsu, the prevention and treatment measures are still not lax. According to the species of toxic, regional economic differences, the scale of the enterprises and the type of economy, the characteristic key classification and prevention should be carried out. Expand the coverage of hospitals in the diagnosis and reporting of occupational poisoning diseases, and strive to improve the quality of occupational disease reports.

Constraining the p-Mode-g-Mode Tidal Instability with GW170817

We analyze the impact of a proposed tidal instability coupling p modes and g modes within neutron stars on GW170817. This nonresonant instability transfers energy from the orbit of the binary to internal modes of the stars, accelerating the gravitational-wave driven inspiral. We model the impact of this instability on the phasing of the gravitational wave signal using three parameters per star: an overall amplitude, a saturation frequency, and a spectral index. Incorporating these additional parameters, we compute the Bayes factor (lnB_{!pg}^{pg}) comparing our p-g model to a standard one. We find that the observed signal is consistent with waveform models that neglect p-g effects, with lnB_{!pg}^{pg}=0.03_{-0.58}^{+0.70} (maximum a posteriori and 90% credible region). By injecting simulated signals that do not include p-g effects and recovering them with the p-g model, we show that there is a ≃50% probability of obtaining similar lnB_{!pg}^{pg} even when p-g effects are absent. We find that the p-g amplitude for 1.4  M_{⊙} neutron stars is constrained to less than a few tenths of the theoretical maximum, with maxima a posteriori near one-tenth this maximum and p-g saturation frequency ∼70  Hz. This suggests that there are less than a few hundred excited modes, assuming they all saturate by wave breaking. For comparison, theoretical upper bounds suggest ≲10^{3} modes saturate by wave breaking. Thus, the measured constraints only rule out extreme values of the p-g parameters. They also imply that the instability dissipates ≲10^{51}  erg over the entire inspiral, i.e., less than a few percent of the energy radiated as gravitational waves.

[Expression and distribution of programmed death receptor 1 and T cell immunoglobulin mucin 3 in breast cancer microenvironment and its relationship with clinicopathological features]

Objective: To explore the expression and distribution of programmed death receptor 1 (PD-1) and T-cell immunoglobulin mucin 3 (TIM-3) in breast cancer microenvironment and analyze the their correlation with the clinicopathological features. Methods: The specimens of tumor tissue and adjacent tissues from 30 patients with infiltrative breast cancer who were diagnosed as breast cancer from June 2016 to May 2017 in The First Hospital of Jiaxing were collected, and the specimen were divided into two parts along the center. After embedding and cryosectioning, the expression and distribution of PD-1 and TIM-3 protein in tumor tissues were observed by immunofluorescence staining. Another part of the specimen was cut and digested, and non-continuous density gradient centrifugation was used to extract tumor-infiltrating lymphocytes (TILs), real-time quantitative PCR (qRT-PCR) was used to detect the mRNA expression of PD-1 and TIM-3 in TILs. Meanwhile, the protein expression was determined by Western blotting. The relationship between the expression of PD-1 and TIM-3 and pathological parameters of breast cancer was analyzed with correlation analysis. Results: Immunofluorescence results showed that more PD-1 and TIM-3 positive cells were observed in the tumor tissues compared with the tumor-adjacent tissues. The qRT-PCR showed that the expression of PD-1 and TIM-3 mRNA in TILs were both significantly higher than those in paracancerous tissues (3.09±0.38 vs 1.26±0.23, 3.42±0.31 vs 1.57±0.29, t=4.16, 4.37, both P<0.05). At the protein level, the expression of PD-1 and TIM-3 in tumor tissue lymphocytes(0.66±0.08, 0.80±0.11) was significantly higher than those in cancerous tissues(0.10±0.01, 0.26±0.02) (t=6.79, 4.57, both P<0.05). There were significant differences in the expression of PD-1, TIM-3 mRNA in the TILs between the different tumor histological grades, tumor sizes, lymph node metastasis (t=2.22-2.99, all P<0.05). Correlation analysis showed that there was a significant positive correlation between the expression of PD-1 and TIM-3 in tumor tissues (r=0.616, P<0.01). Conclusions: In the breast cancer microenvironment, PD-1, TIM-3-mediated signaling pathway plays an important role in the occurrence and development of breast cancer, it provides a new basis for the combination therapy of breast cancer.

Utility of Dynamic Susceptibility Contrast Perfusion-Weighted MR Imaging and 11C-Methionine PET/CT for Differentiation of Tumor Recurrence from Radiation Injury in Patients with High-Grade Gliomas

BACKGROUND AND PURPOSE

Both ¹¹C-methionine PET/CT and DSC-PWI could be used to differentiate radiation injury from recurrent brain tumors. Our aim was to assess the performance of MET PET/CT and DSC-PWI for differentiation of recurrence and radiation injury in patients with high-grade gliomas and to quantitatively analyze the diagnostic values of PET and PWI parameters.

MATERIALS AND METHODS

Forty-two patients with high-grade gliomas were enrolled in this study. The final diagnosis was determined by histopathologic analysis or clinical follow-up. PWI and PET parameters were recorded and compared between patients with recurrence and those with radiation injury using Student t tests. Receiver operating characteristic and logistic regression analyses were used to determine the diagnostic performance of each parameter.

RESULTS

The final diagnosis was recurrence in 33 patients and radiation injury in 9. PET/CT showed a patient-based sensitivity and specificity of 0.909 and 0.556, respectively, while PWI showed values of 0.667 and 0.778, respectively. The maximum standardized uptake value, mean standardized uptake value, tumor-to-background maximum standardized uptake value, and mean relative CBV were significantly higher for patients with recurrence than for patients with radiation injury. All these parameters showed a high discriminative power in receiver operating characteristic analysis. The optimal cutoff values for the tumor-to-background maximum standardized uptake value and mean relative CBV were 1.85 and 1.83, respectively, and corresponding sensitivities and specificities for the diagnosis of recurrence were 0.97 and 0.667 and 0.788 and 0.88, respectively. Areas under the curve for the tumor-to-background maximum standardized uptake value and mean relative CBV were 0.847 ± 0.077 and 0.845 ± 0.078, respectively. Combined assessment of the tumor-to-background maximum standardized uptake value and mean relative CBV showed the largest area under the curve (0.953 ± 0.031), with corresponding sensitivity and specificity of 0.848 and 1.0, respectively.

CONCLUSIONS

Both ¹¹C-methionine PET/CT and PWI are equally accurate in the differentiation of recurrence from radiation injury in patients with high-grade gliomas, and a combination of the 2 modalities could result in increased diagnostic accuracy.

Search for Subsolar-Mass Ultracompact Binaries in Advanced LIGO's First Observing Run

We present the first Advanced LIGO and Advanced Virgo search for ultracompact binary systems with component masses between 0.2  M_{⊙}-1.0  M_{⊙} using data taken between September 12, 2015 and January 19, 2016. We find no viable gravitational wave candidates. Our null result constrains the coalescence rate of monochromatic (delta function) distributions of nonspinning (0.2  M_{⊙}, 0.2  M_{⊙}) ultracompact binaries to be less than 1.0×10^{6}  Gpc^{-3}  yr^{-1} and the coalescence rate of a similar distribution of (1.0  M_{⊙}, 1.0  M_{⊙}) ultracompact binaries to be less than 1.9×10^{4}  Gpc^{-3}  yr^{-1} (at 90% confidence). Neither black holes nor neutron stars are expected to form below ∼1  M_{⊙} through conventional stellar evolution, though it has been proposed that similarly low mass black holes could be formed primordially through density fluctuations in the early Universe and contribute to the dark matter density. The interpretation of our constraints in the primordial black hole dark matter paradigm is highly model dependent; however, under a particular primordial black hole binary formation scenario we constrain monochromatic primordial black hole populations of 0.2  M_{⊙} to be less than 33% of the total dark matter density and monochromatic populations of 1.0  M_{⊙} to be less than 5% of the dark matter density. The latter strengthens the presently placed bounds from microlensing surveys of massive compact halo objects (MACHOs) provided by the MACHO and EROS Collaborations.

In situ recombination junction between p-Si and TiO2 enables high-efficiency monolithic perovskite/Si tandem cells

Increasing the power conversion efficiency of silicon (Si) photovoltaics is a key enabler for continued reductions in the cost of solar electricity. Here, we describe a two-terminal perovskite/Si tandem design that increases the Si cell's output in the simplest possible manner: by placing a perovskite cell directly on top of the Si bottom cell. The advantageous omission of a conventional interlayer eliminates both optical losses and processing steps and is enabled by the low contact resistivity attainable between n-type TiO₂ and Si, established here using atomic layer deposition. We fabricated proof-of-concept perovskite/Si tandems on both homojunction and passivating contact heterojunction Si cells to demonstrate the broad applicability of the interlayer-free concept. Stabilized efficiencies of 22.9 and 24.1% were obtained for the homojunction and passivating contact heterojunction tandems, respectively, which could be readily improved by reducing optical losses elsewhere in the device. This work highlights the potential of emerging perovskite photovoltaics to enable low-cost, high-efficiency tandem devices through straightforward integration with commercially relevant Si solar cells.

[Mutational analysis of RNA splicing machinery genes SF3B1, U2AF1 and SRSF2 in 118 patients with myelodysplastic syndromes and related diseases]

目的

探讨RNA剪接体复合物编码基因SF3B1、U2AF1和SRSF2突变在MDS及相关疾病中的突变率、突变特点及临床意义。

方法

以118例MDS及相关疾病患者为研究对象，采用PCR扩增产物直接测序法分别检测SF3B1（K700E）、U2AF1（S34、Q157P）和SRSF2（P95）突变情况。

结果

118例MDS患者中，男76例，女42例，中位年龄53.5（13~84）岁。对全部患者均进行SF3B1（K700E）基因突变分析，SF3B1（K700E）的突变率为19.49%（118例中23例）。在突变的22例MDS患者中，14例环形铁粒幼红细胞（RS）比例≥15%，其中难治性贫血伴环状铁粒幼红细胞（RARS）7例、难治性血细胞减少伴有多系发育异常（RCMD）6例、难治性贫血（RA）1例。与未突变组相比，突变组患者的年龄偏大[58（32~78）岁对51（13~84）岁，z=−1.981，P=0.048]、PLT偏高[121（22~888）×10⁹/L对59（6~1 561）× 10⁹/L，z=−3.305，P=0.001]、骨髓原始细胞比例偏低[0.007（0~0.122）对0.017（0~0.268），z=−2.885，P=0.004]、RS比例偏高[0（0~64%）对0（0~58%），z=−4.664，P<0.001]，HGB偏低[63（40~95）g/L对77（34~144）g/L，z=−3.192，P=0.001]。对105例患者进行U2AF1（S34、Q157P）基因突变分析，突变率为21.90%（105例中23例）。突变组患者各临床特征与未突变组相比差异均无统计学意义。107例患者有SRSF2（P95）突变结果，8例突变，突变率为7.48%，突变组患者初诊时年龄偏高，中位年龄63（50~84）岁，其中难治性贫血伴有原始细胞增多-1（RAEB-1）4例，突变率为14.29%（28例中4例）；MDS转化的急性髓系白血病3例。1例患者同时出现SF3B1（K700E）和SRSF2（P95H）突变，2例患者同时出现SF3B1（K700E）和U2AF1（S34Y）突变。

结论

SF3B1、U2AF1和SRSF2剪接体复合物蛋白编码基因中，仅SF3B1基因突变与环状铁粒幼红细胞增多性贫血密切相关，是该亚型的主要致病基因。

Combined texture analysis of diffusion-weighted imaging with conventional MRI for non-invasive assessment of IDH1 mutation in anaplastic gliomas

AIM

To examine whether texture analysis (TA) of diffusion-weighted imaging (DWI) combined with conventional magnetic resonance imaging (MRI) could non-invasively predict isocitrate dehydrogenase 1 (IDH1) mutational status in anaplastic gliomas.

MATERIALS AND METHODS

Fifty-two patients with histologically confirmed anaplastic glioma was reviewed retrospectively. Conventional MRI was evaluated using the Visually Accessible Rembrandt Images (VASARI) scoring system. TA of DWI based on the entire tumour volume was compared between IDH1-mutant and wild-type tumours by using unpaired Student's t-test. Receiver operating characteristic curve (ROC) and logistic regression were used to assess their diagnostic performance.

RESULTS

Significant statistical differences in VASARI features and TA of DWI were observed between IDH1-mutant and wild-type tumours (all p<0.05). Using multivariable logistic regression, the proportion of the tumour that was non-enhancing and the entropy of apparent diffusion coefficient (ADC) were found to possess higher prediction potential for IDH1 mutation with areas under the ROC curve (AUC) of 0.918 and 0.724, respectively. A combination of these for the identification of IDH1 mutations improved the AUC to 0.954, with a sensitivity and a specificity of 81% and 96%.

CONCLUSIONS

The combined assessment of the conventional MRI and TA of DWI were useful for predicting IDH1 mutation in anaplastic gliomas.

GW170817: Measurements of Neutron Star Radii and Equation of State

On 17 August 2017, the LIGO and Virgo observatories made the first direct detection of gravitational waves from the coalescence of a neutron star binary system. The detection of this gravitational-wave signal, GW170817, offers a novel opportunity to directly probe the properties of matter at the extreme conditions found in the interior of these stars. The initial, minimal-assumption analysis of the LIGO and Virgo data placed constraints on the tidal effects of the coalescing bodies, which were then translated to constraints on neutron star radii. Here, we expand upon previous analyses by working under the hypothesis that both bodies were neutron stars that are described by the same equation of state and have spins within the range observed in Galactic binary neutron stars. Our analysis employs two methods: the use of equation-of-state-insensitive relations between various macroscopic properties of the neutron stars and the use of an efficient parametrization of the defining function p(ρ) of the equation of state itself. From the LIGO and Virgo data alone and the first method, we measure the two neutron star radii as R_{1}=10.8_{-1.7}^{+2.0}  km for the heavier star and R_{2}=10.7_{-1.5}^{+2.1}  km for the lighter star at the 90% credible level. If we additionally require that the equation of state supports neutron stars with masses larger than 1.97  M_{⊙} as required from electromagnetic observations and employ the equation-of-state parametrization, we further constrain R_{1}=11.9_{-1.4}^{+1.4}  km and R_{2}=11.9_{-1.4}^{+1.4}  km at the 90% credible level. Finally, we obtain constraints on p(ρ) at supranuclear densities, with pressure at twice nuclear saturation density measured at 3.5_{-1.7}^{+2.7}×10^{34}  dyn cm^{-2} at the 90% level.

[Incidence of occupational diseases in a province of China during the period of "Twelfth Five-Year Plan" and its trend]

Objective: To investigate the incidence of occupational diseases in a province of China during the period of "Twelfth Five-Year Plan" , and to analyze the features of disease spectrum, the characteristics of regional and industrial distribution, and incidence trend. Methods: Data (2011-2015) were collected from the Information System of Occupational Diseases and Occupational Health to analyze the reported cases of occupational diseases during the period of "Twelfth Five-Year Plan". A statistical analysis was performed to identify the characteristics of the disease distribution in terms of sex, age, working years, enterprise type, enterprise scale, and region, as well as the incidence trend. Results: The overall incidence of occupational diseases in this province fluctuated and decreased gradually. There were a total of 5036 new cases of occupational diseases during the period of "Twelfth Five-Year Plan" ; 89.45% of them were male, and 69.78% of them were aged 40-69 years; the most frequently seen occupational diseases were pneumoconiosis (72.48%) and ear, nose, throat, and oral diseases (7.23%). Most cases of pneumoconiosis occurred after 5-10 years of exposure, and other occupational diseases usually developed within 10 years of exposure. New cases of occupational diseases were often seen in small and micro enterprises, as well as Wuxi, Suzhou, and Yancheng. Conclusion: During the period of "Twelfth Five-Year Plan" , the incidence of occupational diseases in this province decreased gradually, indicating improved control of occupational diseases, but we still need to pay attention to the high-risk population (male, aged over 40 years) , as well as the prevention of occupational noise-induced hearing loss, and to strengthen the supervision of small and micro enterprises.

[Value analysis of preoperative and intra-operative ultrasound in diagnosis and treatment of parathyroid adenoma]

Objective:To explore the value characteristics of preoperative and intra-operative ultrasound in the diagnosis and treatment of parathyroid adenoma,and to further clarify the value of ultrasound in the diagnosis and treatment of parathyroid adenoma.Method:A total of 62 cases of parathyroid adenoma confirmed by postoperative pathology from March 2016 to November 2017 were collected, and the pre-operative ultrasound parameters were analyzed;and 26 cases were detected by intra-operative ultrasound.Result:In 62 cases of parathyroid adenoma, 58 cases of parathyroid adenoma were diagnosed by ultrasound before operation,and the sensitivity was 93.54%. Among the 26 cases,the lesions of 24 cases were detected by intra-operative ultrasound,and the sensitivity was 92.31%.Conclusion:Preoperative ultrasonography has a high diagnostic value for the qualitative diagnosis and location diagnosis of parathyroid adenoma, and intra-operative ultrasound can help to detect lesions quickly and safely, which is of great significance to shorten the operation time and improve the safety of operation. It is an important development space of ultrasound in the diagnosis and treatment of parathyroid glands.

[Analysis and surgical treatment of 72 cases of parapharyngeal space tumors]

Objective:To summarize and analyze the clinical features, diagnosis methods, surgical approaches and treatment outcomes of patients with parapharygeal space tumors.Method:A retrospective review of 72 cases with parapharygeal space tumors treated from March 1994 to June 2017 was performed. The data on presentation, surgical approach, histological diagnosis and postoperative complications were reviewed.Result:The postoperative pathological diagnosis included 62 benign tumors and 10 malignant tumors. The most frequent symptom was a cervical mass or an intraoral swelling. All patients underwent preoperative enhanced CT scan or MRI,which would be helpful to evaluate the tumor sizes,locations and possible sources,and to make operation scheme. The postoperative pathology included 24 salivary gland lesions and 30 neurogenic lesions. The postoperative complications happened in 13 patients. The surgical approaches included trans-cervical approach in 55 cases, cervical-parotid approach in 9 cases,trans-oral approach in 6 cases , and trans skull base approach in 2 case.Conclusion:A parapharygeal space tumor is an uncommon tumor and requires careful preoperative assessment. Surgery is the first choice for parapharygeal space tumors. These patients should be counseled appropriately about the potential for permanent cranial nerve deficits.

Curcumin Inhibits Proliferation and Epithelial-Mesenchymal Transition of Retinal Pigment Epithelial Cells Via Multiple Pathways

BACKGROUND

Proliferative vitreoretinopathy (PVR) is a disease caused by dedifferentiation, translocation and proliferation of several types of local cells. These cells form fibrocellular membranes resulting in detachment of retinal and vision loss. PVR occurs in 8%-10% of patients undergoing primary retinal detachment (RD) surgery and becomes a major obstacle for successful RD repair. Retinal pigment epithelial (RPE) cells are among the major cells which consist of fibrocellular membranes. Reproliferation and Epithelial-mesenchymal transition (EMT) are the primary pathological alteration of RPE cells in PVR.

METHODS

RPE cells were treated with curcumin at different concentrations for 24, 48 and 72 hours. The viable cells were detected by MTT assay. The apoptosis of RPE was stained by Multicaspase/7-AAD and detected using flow cytometry. Cell cycle analysis was quantified by PI staining. The mRNA levels were detected by real-time PCR. The protein levels were detected by western blot.

RESULTS

We found a compound curcumin significantly inhibited proliferation and EMT of RPE cells in vitro. Further study showed curcumin induced cell cycle arrest by activating G2 checkpoint through p53 pathway. Meanwhile, we found that curcumin suppressed the AKT, MAPK and TGF-β pathways in RPE cells which may also affect proliferation and EMT. Our research identified curcumin a potential novel agent for the PVR prevention and treatment. Curcumin induces cell cycle arrest by activating G2 checkpoint.

CONCLUSION

Our results in this study also provide the insights to broaden the application of curcumin in research and probably clinics.

Perovskite Photovoltaic Integrated CdS/TiO2 Photoanode for Unbiased Photoelectrochemical Hydrogen Generation

Photoelectrolysis of water using solar energy into storable and environment-friendly chemical fuel in the form of hydrogen provides a potential solution to address the environmental concerns and fulfill future energy requirements in a sustainable manner. Achieving efficient and spontaneous hydrogen evolution in water using solar light as the only energy input is a highly desirable but a difficult target. In this work, we report perovskite solar cell integrated CdS-based photoanode for unbiased photoelectrochemical hydrogen evolution. An integrated tandem device consisting of mesoporous CdS/TiO₂ photoanode paired with a triple-cation perovskite (Cs_0.05(MA_0.17FA_0.83)_0.95Pb(I_0.83Br_0.17)₃) solar cell is developed via a facile fabrication route. The proposed photovoltaic integrated photoanode presents an efficient tandem configuration with high optical transparency to long-wavelength photons and strong photoelectrochemical conversions from short-wavelength photons. On the basis of this integrated tandem device, an unbiased photocurrent density of 7.8 mA/cm² is demonstrated under AM1.5G illumination.

Hybrid PbS Quantum-Dot-in-Perovskite for High-Efficiency Perovskite Solar Cell

In this study, a facile and effective approach to synthesize high-quality perovskite-quantum dots (QDs) hybrid film is demonstrated, which dramatically improves the photovoltaic performance of a perovskite solar cell (PSC). Adding PbS QDs into CH3 NH3 PbI3 (MAPbI3 ) precursor to form a QD-in-perovskite structure is found to be beneficial for the crystallization of perovskite, revealed by enlarged grain size, reduced fragmentized grains, enhanced characteristic peak intensity, and large percentage of (220) plane in X-ray diffraction patterns. The hybrid film also shows higher carrier mobility, as evidenced by Hall Effect measurement. By taking all these advantages, the PSC based on MAPbI3 -PbS hybrid film leads to an improvement in power conversion efficiency by 14% compared to that based on pure perovskite, primarily ascribed to higher current density and fill factor (FF). Ultimately, an efficiency reaching up to 18.6% and a FF of over ≈0.77 are achieved based on the PSC with hybrid film. Such a simple hybridizing technique opens up a promising method to improve the performance of PSCs, and has strong potential to be applied to prepare other hybrid composite materials.

Optical Properties and Local Structure Evolution during Crystallization of Ga16Sb84 Alloy

Phase-change memory is one of the most promising candidates for future memory technologies. However, most of the phase-change memories are based on chalcogenides, while other families of materials for this purpose remain insufficiently studied. In this work, we investigate the optical properties and microstructure of Ga16Sb84 by an in-situ ellipsometer and X-ray diffraction. Our experimental results reveal that the Ga16Sb84 films exhibit a relatively high crystallization temperature of ~250 °C, excelling in long data retention. In addition, a large optical contrast exists between the amorphous and crystalline states, which may make it suitable for use in optical discs. Molecular dynamics simulations indicate that a unique local structure order in the amorphous and crystalline phases is responsible for the optical properties observed in the experiment. The similarity found in the short-range orders of the amorphous and crystalline phases is beneficial to better understanding the fast phase transition of phase-change memory.

New insights into the origin of hysteresis behavior in perovskite solar cells

Perovskite solar cells (PSCs) have received tremendous attention due to their stunning progress in photovoltaic performance. The hysteresis behavior, however, is one of the major concerning issues accompanying the development of PSCs. In this context, we propose a new mechanism that explains the origin of hysteresis behavior by analyzing the electrical processes after changing the external electrical bias: the compensating electric field to the scanning voltage induced by drifting carriers. This is further verified by experiments, where we observed much reduced hysteresis in the current density-voltage (J-V) characteristics for the PSCs based on a thinner perovskite layer, which is a result of more evenly distributed electrons and holes. Moreover, light illumination with different wavelengths was applied to vary the initial carrier distribution inside the perovskite layer. We found that J-V curves when illuminating the device with longer wavelengths exhibited diminished hysteresis, which could be a result of more evenly generated carriers due to a smaller absorptivity than that with short wavelength illumination. Based on the proposed model, three key factors affecting the hysteresis behavior were pointed out, including the initial carrier distribution, the carrier transport properties in the perovskite layer, and the carrier extraction properties at the interfaces. Strategies to construct hysteresis-free and stable PSCs have thus been accordingly proposed.

LOH12CR1 is a Novel Tumor Suppressor Inhibiting Tumor Growth Through Deregulation of G1/S Checkpoint in Human Colorectal Carcinoma

BACKGROUND

Loss of heterozygosity (LOH) of 12p12-13 has been frequently found in various types of cancer. LOH12CR1 is one of the seven critical genes located within the 12p12-13 region. The protein encoded by LOH12CR1 is involved in the function of lysosomes and its other functions are still unclear.

OBJECTIVE

The aim of this study is to investigate the potential roles of LOH12CR1 in the development of colorectal cancer.

METHODS

A total of 174 colorectal cancer tissues were used to examine the protein level of LOH12CR1 by immunohistochemistry staining. The correlation between LOH12CR1 expression and the patient prognosis was further investigated through retrospective study. The tumor suppression capacity was examined by knockdown or overexpression of LOH12CR1 in four colorectal cancer cell lines and one normal cell line.

RESULTS

Significant decrease of LOH12CR1 protein was observed in colorectal cancerous tissues (P<0.001). Knockdown of LOH12CR1 promoted colorectal cancer cell proliferation, colony formation, and accelerated G1/S cell cycle transition through downregulation of p16^INK4a and p21^WAF1/CIP1, while ectopic expression of LOH12CR1 displayed the opposite effects. The protein level of LOH12CR1 was well correlated with the expression of p16^INK4a and p21^WAF1/CIP1. Most importantly, the protein level of LOH12CR1 negatively correlated with clinical prognosis of colorectal carcinomas.

CONCLUSION

The present results suggest that LOH12CR1 might function as a tumor suppressor. Thus, loss of function of LOH12CR1 might be a potential driver in the development of colorectal carcinoma. Detection of LOH12CR1 could be used as a method for diagnosis and therapeutic assessment of patients with colorectal cancer.

Targeted methylation sequencing of plasma cell-free DNA for cancer detection and classification

Background

Targeted methylation sequencing of plasma cell-free DNA (cfDNA) has a potential to expand liquid biopsies to patients with tumors without detectable oncogenic alterations, which can be potentially useful in early diagnosis.

Patients and methods

We developed a comprehensive methylation sequencing assay targeting 9223 CpG sites consistently hypermethylated according to The Cancer Genome Atlas. Next, we carried out a clinical validation of our method using plasma cfDNA samples from 78 patients with advanced colorectal cancer, non-small-cell lung cancer (NSCLC), breast cancer or melanoma and compared results with patients' outcomes.

Results

Median methylation scores in plasma cfDNA samples from patients on therapy were lower than from patients off therapy (4.74 versus 85.29; P = 0.001). Of 68 plasma samples from patients off therapy, methylation scores detected the presence of cancer in 57 (83.8%), and methylation-based signatures accurately classified the underlying cancer type in 45 (78.9%) of these. Methylation scores were most accurate in detecting colorectal cancer (96.3%), followed by breast cancer (91.7%), melanoma (81.8%) and NSCLC (61.1%), and most accurate in classifying the underlying cancer type in colorectal cancer (88.5%), followed by NSCLC (81.8%), breast cancer (72.7%) and melanoma (55.6%). Low methylation scores versus high were associated with longer survival (10.4 versus 4.4 months, P < 0.001) and longer time-to-treatment failure (2.8 versus 1.6 months, P = 0.016).

Conclusions

Comprehensive targeted methylation sequencing of 9223 CpG sites in plasma cfDNA from patients with common advanced cancers detects the presence of cancer and underlying cancer type with high accuracy. Methylation scores in plasma cfDNA correspond with treatment outcomes.

Detection and genetic characterization of porcine pegivirus in pigs in the United States

Using next-generation sequencing on vesicular swab and serum from swine from the USA exhibiting lameness and vesicles, porcine pegivirus (PPgV) was first identified and genetically characterized in the United States. Further screening using RT-PCR revealed that 24 of 159 (15.1%) serum samples were positive for PPgV. Future studies are needed to understand clinical impacts of the virus.

Bifacial Modified Charge Transport Materials for Highly Efficient and Stable Inverted Perovskite Solar Cells

Significant efforts have been devoted to enhancing both the performance and long-term stability of lead halide perovskite solar cells (PSCs) to promote their practical application. In this context, a self-assembled monolayer composed of a dye molecule is demonstrated for the first time to be efficient in passivating the surface of the hole transport layer, NiO _x, in the p-i-n PSCs through multiple functions, including the minimization of energy-level offset, reducing surface trap states, and enhancing wetting between NiO _x and perovskite layers coupled with increasing perovskite crystallinity. Consequently, the dye monolayer has sufficiently improved the hole extraction efficiency and suppressed the charge recombination, validated by steady and transient photoluminescence measurements and the electrochemical impedance analysis. Concurrently, a mixed layer of BaSnO₃ nanoparticles and [6,6]-phenyl-C₆₁-butyric acid methyl (PCBM) (barium stannate (BSO)/PCBM) was exploited as an efficient electron transport layer, resulting in superior electron transport properties and correspondingly excellent device stability. By incorporating these bifacial modifications, the device performance of the inverted PSC was propelled to 16.2%, compared with 14.0% for that without any interfacial and compositional engineering. Benefiting from the excellent crystallinity of the perovskite through dye passivation and the blocking of moisture, oxygen, and ion migration by using the hybrid BSO/PCBM layer, over 90% of the initial power conversion efficiency has been preserved for the device after exposure to ambient air for 650 h.

Clinical and molecular insights into Glanzmann's thrombasthenia in China

Glanzmann's thrombasthenia (GT) is a rare bleeding disorder characterized by spontaneous mucocutaneous bleeding. The disorder is caused by quantitative or qualitative defects in integrin αIIbβ3 (encoded by ITGA2B and ITGB3) on the platelet and is more common in consanguineous populations. However, the prevalence rate and clinical characteristics of GT in non-consanguineous populations have been unclear. We analyzed 97 patients from 93 families with GT in the Han population in China. This analysis showed lower consanguinity (18.3%) in Han patients than other ethnic populations in GT-prone countries. Compared with other ethnic populations, there was no significant difference in the distribution of GT types. Han females suffered more severe bleeding and had a poorer prognosis. We identified a total of 43 different ITGA2B and ITGB3 variants, including 25 previously unidentified, in 45 patients. These variants included 14 missense, 4 nonsense, 4 frameshift, and 3 splicing site variants. Patients with the same genotype generally manifested the same GT type but presented with different bleeding severities. This suggests that GT clinical phenotype does not solely depend on genotype. Our study provides an initial, yet important, clinical and molecular characterization of GT heterogeneity in China.

[The clinical assessment of regional resection in the benign tumor of parotid gland]

Objective:To evaluate the clinical assessment of regional resection and superficial lobe total resection in the treatment of benign tumors of the parotid gland. Method:One hundred and nighty-five patients operated in the First Hospital of Peking University from January 1998 to March 2017 with benign tumor of the parotid gland were retrospectively analyzed. There were 189 patients with single side tumor and 6 patients with bilateral sides, 157 cases underwent regional resection and the other 44 cases underwent superficial lobe total resection. All the results and complications were recorded and analyzed between the two groups.Result:There were total 195 patients with 201 cases. All the complications were as follows, 4 cases with recurrence, 44 cases with temporal facial paralysis, 13 cases with permanent facial paralysis, 80 cases with earlobe numbness, 49 cases with facial numbness, 44 cases with skin retraction, 26 cases with operated region effusion, 2 cases with sialosyrinx, 55 cases with Frey syndrome. There were no significant differences between the two groups in the incidences of recurrence, temporal facial paralysis, permanent facial paralysis, earlobe numbness, facial numbness, skin retraction. The incidence of Frey syndrome in the superficial lobe total resection group was significantly higher than the regional resection group(45.5%, 22.3%，P<0.05). The incidence of operated region effusion or sialosyrinx in the regional resection group was significantly higher than the superficial lobe total resection group (16.6%, 4.5%,P<0.05),further analysis showed that the operation method and the location of the tumor were the independent risk factors. Conclusion:Regional resection in the parotid gland tumor was less invasive, the incidences in the most complications were in consistent with superficial lobe total resection, and it was helpful in preventing the occurrence of Frey syndrome. Although regional resection conserved more parotid gland tissue so that the more conserved gland function and it also did not increase the incidence of sialosyrinx, the operated region effusion was significantly increased. If the operated region effusion was not discovered and handled, there would be a risk of sialosyrinx.

Distribution of ABO/Rh blood groups and their association with hepatitis B virus infection in 3.8 million Chinese adults: A population-based cross-sectional study

ABO and Rh blood groups play a vital role in blood transfusion safety and clinical practice and are thought to be linked with disease susceptibility. The results from previous studies that focused on the association between blood groups and HBV infection remain controversial. China has the world's largest burden of HBV infection. We assessed the distribution of ABO/Rh blood groups in Chinese adults and examined the association between these groups and HBV infection. We did a nationwide cross-sectional study using data from a physical check-up programme from 31 provinces examined between 2010 and 2012. ELISA was used to test for HBsAg in serologic samples. Multivariable logistic regression was used to estimate aOR of the association between ABO and Rh blood groups and HBV infection. Among 3 827 125 participants, the proportion of participants with blood group A was highest (30.54%), followed by O (30.37%), B (29.42%) and AB (9.66%). A total of 38 907 (1.02%) were Rh-D negative. The prevalence of HBsAg in blood groups O, A, B and AB were 6.34%, 5.55%, 5.18% and 5.06%, respectively. HBsAg prevalence was 5.65% in Rh-D-positive and 3.96% in Rh-D-negative participants. After controlling for other potential risk factors, multivariate models showed that participants with blood group O (adjusted OR = 1.22, 95% CI: 1.20-1.25) were at higher risk of HBV infection compared with group AB. Rh-D-positive participants (adjusted OR = 1.44, 95% CI: 1.37-1.52) were at higher risk of HBV infection than Rh-D-negative participants. The associations between ABO/Rh blood groups and HBV infection were similar in subgroup analysis. The proportions of O, A, B and AB blood groups were approximately 3:3:3:1, and nearly 1 in 100 people was Rh-D negative among Chinese adults. Blood group O and Rh-D positivity were both associated with increased HBV infection. The risk of HBV infection and blood safety should be taken into consideration in clinical practice, especially when transfusing those with blood group O. Awareness and prevention of HBV infection is of particular importance for individuals with blood group O.

Impacts of Regulations on Air Quality and Emergency Department Visits in the Atlanta Metropolitan Area, 1999-2013

INTRODUCTION

The United States and Western Europe have seen great improvements in air quality, presumably in response to various regulations curtailing emissions from the broad range of sources that have contributed to local, regional, and global pollution. Such regulations, and the ensuing controls, however, have not come without costs, which are estimated at tens of billions of dollars per year. These costs motivate accountability-related questions such as, to what extent do regulations lead to emissions changes? More important, to what degree have the regulations provided the expected human health benefits?

Here, the impacts of specific regulations on both electricity generating unit (EGU) and on-road mobile sources are examined through the classical accountability process laid out in the 2003 Health Effects Institute report linking regulations to emissions to air quality to health effects, with a focus on the 1999-2013 period. This analysis centers on regulatory actions in the southeastern United States and their effects on health outcomes in the 5-county Atlanta metropolitan area. The regulations examined are largely driven by the 1990 Clean Air Act Amendments (C). This work investigates regulatory actions and controls promulgated on EGUs: the Acid Rain Program (ARP), the NOx Budget Trading Program (NBP), and the Clean Air Interstate Rule (CAIR) - and mobile sources: Tier 2 Gasoline Vehicle Standards and the 2007 Heavy Duty Diesel Rule.

METHODS

Each step in the classic accountability process was addressed using one or more methods. Linking regulations to emissions was accomplished by identifying major federal regulations and the associated state regulations, along with analysis of individual facility emissions and control technologies and emissions modeling (e.g., using the U.S. Environmental Protection Agency's [U.S. EPA's] MOtor Vehicle Emissions Simulator [MOVES] mobile-source model). Regulators, including those from state environmental and transportation agencies, along with the public service commissions, play an important role in implementing federal rules and were involved along with other regional stakeholders in the study. We used trend analysis, air quality modeling, satellite data, and a ratio-of-ratios technique to investigate a critical current issue, a potential large bias in mobile-source oxides of nitrogen (NOx) emissions estimates.

The second link, emissions-air quality relationships, was addressed using both empirical analyses as well as chemical transport modeling employing the Community Multiscale Air Quality (CMAQ) model. Kolmogorov-Zurbenko filtering accounting for day of the year was used to separate the air quality signal into long-term, seasonal, weekday-holiday, and short-term meteorological signals. Regression modeling was then used to link emissions and meteorology to ambient concentrations for each of the species examined (ozone [O3], particulate matter ≤ 2.5 μm in aerodynamic diameter [PM2.5], nitrogen dioxide [NO2], sulfur dioxide [SO2], carbon monoxide [CO], sulfate [SO4-2], nitrate [NO3-], ammonium [NH4+], organic carbon [OC], and elemental carbon [EC]). CMAQ modeling was likewise used to link emissions changes to air quality changes, as well as to further establish the relative roles of meteorology versus emissions change impacts on air quality trends. CMAQ and empirical modeling were used to investigate aerosol acidity trends, employing the ISORROPIA II thermodynamic equilibrium model to calculate pH based on aerosol composition. The relationships between emissions and meteorology were then used to construct estimated counterfactual air quality time series of daily pollutant concentrations that would have occurred in the absence of the regulations. Uncertainties in counterfactual air quality were captured by the construction of 5,000 pollutant time series using a Monte Carlo sampling technique, accounting for uncertainties in emissions and model parameters.

Health impacts of the regulatory actions were assessed using data on cardiorespiratory emergency department (ED) visits, using patient-level data in the Atlanta area for the 1999-2013 period. Four outcome groups were chosen based on previous studies identifying associations with ambient air pollution: a combined respiratory disease (RD) category; the subgroup of RD presenting with asthma; a combined cardiovascular disease (CVD) category; and the subgroup of CVD presenting with congestive heart failure (CHF).

Models were fit to estimate the joint effects of multiple pollutants on ED visits in a time-series framework, using Poisson generalized linear models accounting for overdispersion, with a priori model formulations for temporal and meteorological covariates and lag structures. Several parameterizations were considered for the joint-effects models, including different sets of pollutants and models with nonlinear pollutant terms and first-order interactions among pollutants. Use of different periods for parameter estimates was assessed, as associations between pollutant levels and ED visits varied over the study period. A 7-pollutant, nonlinear model with pollutant interaction terms was chosen as the baseline model and fitted using pollutant and outcome data from 1999-2005 before regulations might have substantially changed the toxicity of pollutant mixtures. In separate analyses, these models were fitted using pollutant and outcome data from the entire 1999-2013 study period. Daily counterfactual time series of pollutant concentrations were then input into the health models, and the differences between the observed and counterfactual concentrations were used to estimate the impacts of the regulations on daily counts of ED visits. To account for the uncertainty in both the estimation of the counterfactual time series of ambient pollutant levels and the estimation of the health model parameters, we simulated 5,000 sets of parameter estimates using a multivariate normal distribution based on the observed variance-covariance matrix, allowing for uncertainty at each step of the chain of accountability. Sensitivity tests were conducted to assess the robustness of the results.

RESULTS

EGU NOx and SO2 emissions in the Southeast decreased by 82% and 83%, respectively, between 1999 and 2013, while mobile-source emissions controls led to estimated decreases in Atlanta-area pollutant emissions of between 61% and 93%, depending on pollutant. While EGU emissions were measured, mobile-source emissions were modeled. Our results are supportive of a potential high bias in mobile-source NOx and CO emissions estimates. Air quality benefits from regulatory actions have increased as programs have been fully implemented and have had varying impacts over different seasons. In a scenario that accounted for all emissions reductions across the period, observed Atlanta central monitoring site maximum daily 8-hour (MDA8h) O3 was estimated to have been reduced by controls in the summertime and increased in the wintertime, with a change in mean annual MDA8h O3 from 39.7 ppb (counterfactual) to 38.4 ppb (observed). PM2.5 reductions were observed year-round, with average 2013 values at 8.9 μg/m3 (observed) versus 19.1 μg/m3 (counterfactual). Empirical and CMAQ analyses found that long-term meteorological trends across the Southeast over the period examined played little role in the distribution of species concentrations, while emissions changes explained the decreases observed. Aerosol pH, which plays a key role in aerosol formation and dynamics and may have health implications, was typically very low (on the order of 1-2, but sometimes much lower), with little trend over time despite the stringent SO2 controls and SO42- reductions.

Using health models fit from 1999-2005, emissions reductions from all selected pollution-control policies led to an estimated 55,794 cardiorespiratory disease ED visits prevented (i.e., fewer observed ED visits than would have been expected under counterfactual scenarios) - 52,717 RD visits, of which 38,038 were for asthma, and 3,057 CVD visits, of which 2,104 were for CHF - among the residents of the 5-county area over the 1999-2013 period, an area with approximately 3.5 million people in 2013. During the final two years of the study (2012-2013), when pollution-control policies were most fully implemented and the associated benefits realized, these policies were estimated to prevent 5.9% of the RD ED visits that would have occurred in the absence of the policies (95% interval estimate: -0.4% to 12.3%); 16.5% of the asthma ED visits (95% interval estimate: 7.5% to 25.1%); 2.3% of the CVD ED visits (95% interval estimate: -1.8% to 6.2%); and -.6% of the CHF ED visits (95% interval estimate: 26.3% to 10.4%). Estimates of ED visits prevented were generally lower when using health models fit for the entire 1999-2013 study period.

Sensitivity analyses were conducted to show the impact of the choice of parameterization of the health models and to assess alternative definitions of the study area. When impacts were assessed for separate policy interventions, policies affecting emissions from EGUs, especially the ARP and the NBP, appeared to have had the greatest effect on prevention of RD and asthma ED visits.

CONCLUSIONS

This study demonstrates the effectiveness of regulations on improving air quality and health in the southeastern United States. It also demonstrates the complexities of accountability assessments as uncertainties are introduced in each step of the classic accountability process. While accounting for uncertainties in emissions, air quality-emissions relationships, and health models does lead to relatively large uncertainties in the estimated outcomes due to specific regulations, overall the benefits of regulations have been substantial.