Improving the Performances of Perovskite Solar Cells via Modification of Electron Transport Layer

The commonly used electron transport material (6,6)-phenyl-C61 butyric acid methyl ester (PCBM) for perovskite solar cells (PSC) with inverted planar structures suffers from properties such as poor film-forming. In this manuscript, we demonstrate a simple method to improve the film-forming properties of PCBM by doping PCBM with poly(9,9-dioctylfluorene-co-benzothiadiazole) (F8BT) as the electron transport layer (ETL), which effectively enhances the performance of CH₃NH₃PbI₃ based solar cells. With 5 wt % F8BT in PCBM, the short circuit current (JSC) and fill factor (FF) of PSC both significantly increased from 17.21 ± 0.15 mA·cm-2 and 71.1 ± 0.07% to 19.28 ± 0.22 mA·cm-2 and 74.7 ± 0.21%, respectively, which led to a power conversion efficiency (PCE) improvement from 12.6 ± 0.24% to 15 ± 0.26%. The morphology investigation suggested that doping with F8BT facilitated the formation of a smooth and uniform ETL, which was favorable for the separation of electron-hole pairs, and therefore, an improved performance of PSC.

Prevalence and Risk Factors for Frailty among Community-Dwelling Older People in China: A Systematic Review and Meta-Analysis

OBJECTIVE

To systematically assess the prevalence of frailty, including prefrailty, stratified prevalence according to frailty criteria, gender, age, and region, and the risk factors for frailty in China.

DESIGN

We conducted a systematic literature review and meta-analysis using articles available in 8 databases including PubMed, Cochrane Library, Web of Science, CINAHL Plus, China Knowledge Resource Integrated Database (CNKI), Wanfang Database, Chinese Biomedical Database (CBM), and Weipu Database (VIP).

SETTING

Cross-sectional and cohort data from Chinese community.

PARTICIPANTS

Community-dwelling adults aged 65 and older.

MEASUREMENTS

Two authors independently extracted data based upon predefined criteria. Where data were available we conducted a meta-analysis of frailty parameters using a random-effects model.

RESULTS

We screened 915 different articles, and 14 studies (81258 participants) were ultimately included in this analysis. The prevalence of frailty and prefrailty in individual studies varied from 5.9% to 17.4% and from 26.8% to 62.8%, respectively. The pooled prevalence of frailty and prefrailty were 10% (95% CI: 8% to 12%, I2 = 97.4%, P = 0.000) and 43% (95% CI: 37% to 50%, I2 = 98.0%, P = 0.000), respectively. The pooled frailty prevalence was 8% for the Fried frailty phenotype, 12% for the frail index, and 15% for the FRAIL scale. Age-stratified meta-analyses showed the pooled prevalence of frailty to be 6%, 15%, and 25% for those aged 65-74, 75-84, and ≥85 years old, respectively. The pooled prevalence of frailty was 8% for males and 11% for females. The pooled prevalence of frailty in Mainland China, Taiwan, and Hong Kong was 12%, 8%, and 14%, respectively. The pooled frailty prevalence was 10% in urban areas and 7% in rural areas. After controlling for confounding variables, increasing age (OR = 1.28, 95% CI: 1.2 to 1.36, I2 = 98.0%, P = 0.000), being female (OR = 1.29, 95% CI: 1.16 to 1.43, I2 =92.7%, P=0.000), activities of daily living (ADL) disability (OR = 1.72, 95% CI: 1.57 to 1.90, I2 = 99.7%, P = 0.000), and having three or more chronic diseases (OR = 1.97, 95% CI: 1.78 to 2.18, I2 = 97.5%, P = 0.000) were associated with frailty.

CONCLUSIONS

These findings of this review indicate an overall pooled prevalence of frailty among Chinese community-dwelling older people of 10%. Increasing age, being female, ADL disability, and having three or more chronic diseases were all risk factors for frailty. Further research will be needed to identify additional frailty risk factors in order to better treat and prevent frailty in the community.

[Clinical efficacy of recombinant activated factor Ⅶ a for 16 hematonosis with moderate or severe bleeding]

目的

观察重组人凝血因子Ⅶa（rFⅦa）对血液病及其异基因造血干细胞移植（allo-HSCT）术后出血患者的止血疗效。

方法

以2013年5月至2016年5月住院治疗的16例合并中至重度出血的血液病患者为观察对象，非移植组及移植组患者各8例，两组患者应用rFⅦa的用法、用量无明显差异。同时，以同期15例allo-HSCT后发生肠道急性移植物抗宿主病（aGVHD）肠出血患者为对照组（未应用rFⅦa），将其与allo-HSCT后肠道aGVHD肠出血应用rFⅦa患者进行生存比较，总结患者应用rFⅦa治疗的临床疗效。

结果

①非移植组与移植组患者中，rFⅦa止血显效率分别为75.0%（6/8）和37.5%（3/8），显效中位时间分别为38.5和63.0 h，中位总生存（OS）时间分别为201.0和29.0 d，OS率分别为50.0%（4/8）和25.0%（2/8），出血相关死亡率分别为50.0%（2/4）和83.3%（5/6）。②16例患者中显效者9例，无效者7例，显效组与无效组患者中，中位OS时间分别为268.0和24.0 d，OS率分别为66.7%（6/9）和0（0/7）。③同期肠道aGVHD合并肠出血患者，观察组（6例）与对照组（15例）患者的中位OS时间分别为25.5和20.0 d。

结论

血液病患者尤其是allo-HSCT患者出血相关死亡率高，rFⅦa治疗有一定止血疗效；显效组患者OS率较无效组高；allo-HSCT后肠道出血患者采用rFⅦa治疗止血效果不佳的原因可能与移植后导致出血的并发症控制不佳有关。

Search for CP Violation in Neutrino and Antineutrino Oscillations by the T2K Experiment with 2.2×10^{21} Protons on Target

The T2K experiment measures muon neutrino disappearance and electron neutrino appearance in accelerator-produced neutrino and antineutrino beams. With an exposure of 14.7(7.6)×10^{20} protons on target in the neutrino (antineutrino) mode, 89 ν_{e} candidates and seven anti-ν_{e} candidates are observed, while 67.5 and 9.0 are expected for δ_{CP}=0 and normal mass ordering. The obtained 2σ confidence interval for the CP-violating phase, δ_{CP}, does not include the CP-conserving cases (δ_{CP}=0, π). The best-fit values of other parameters are sin^{2}θ_{23}=0.526_{-0.036}^{+0.032} and Δm_{32}^{2}=2.463_{-0.070}^{+0.071}×10^{-3}  eV^{2}/c^{4}.

Electrocatalysis of polysulfide conversion by conductive RuO2 nano dots for lithium-sulfur batteries

The practical use of the rechargeable lithium-sulfur (Li-S) battery is still restricted by poor cycle life and rate performance caused by the shuttle of soluble redox intermediates and low conductivity of S/Li2S. A comprehensive approach is to tune the multi-electron redox reactions and construct reversible chemical bonds with polysulfide intermediates. In this study, RuO2 nano dots (NDs) are proposed to anchor polysulfides, trigger the surface-mediated reduction of polysulfides and to facilitate the formation of Li2S2/Li2S through its catalytic effect for the first time. When serving as the sulfur host, the RuO2 NDs can retard the shuttle of polysulfides, accelerate the redox reaction of polysulfides, and therefore result in improved sulfur utilization and enhanced rate performance. The designed RuO2@NMCs/S ternary electrodes with high sulfur loading of 70 wt% could achieve a low decay rate of 0.07% per cycle for 500 cycles at a 0.5 C-rate. Realized by fast electrode kinetics, the reversible capacity of 634 mA h g-1 is attained at a high C-rate of 5 C. Overall, this strategy sheds new light on the oxide mediators for reversible modulation of electrochemical reactions in lithium-sulfur (Li-S) batteries.

Exercise Training Induced Cardioprotection with Moderate Hyperglycemia versus Sedentary Intensive Glycemic Control in Type 1 Diabetic Rats

Intensive insulin therapy (IIT; 4-7 mmol/L) is the preferred treatment for type 1 diabetes mellitus (T1DM) patients to reduce the risk of cardiovascular disease (CVD). However, this treatment strategy has been questioned as it is accompanied with a sedentary lifestyle leading to weight gain and insulin resistance. T1DM patients who partake in high-intensity aerobic training (AThigh) to reduce CVD often utilize conventional insulin therapy (CIT; 9-15 mmol/L) to offset the risk of hypoglycemia. Moreover, exercise modalities incorporating resistance training (RT) have been shown to further reduce this risk. The purpose of this investigation was twofold: (1) to determine if CIT paired with AThigh results in larger cardioprotection from an ischemia-reperfusion (I-R) injury than IIT and (2) to establish if the integration of RT with AThigh (ART) results in similar cardioprotection as AThigh. Diabetic (D) male Sprague-Dawley rats were divided into D-IIT (n = 12), D-CIT (n = 12), D-AThigh (n = 8), D-RT (n = 8), and D-ART (n = 8). T1DM was induced with streptozotocin, and blood glucose was adjusted with insulin. D-AThigh occurred on a treadmill (27 m/min; 1 hr), D-RT performed weighted ladder climbs, and D-ART alternated daily between AThigh and RT. Exercise occurred 5 days/wk for 12 wks. This investigation demonstrates that cardioprotection following an I-R injury was similar between D-AThigh and D-IIT. This cardioprotection is not exercise-specific, and each provides unique advantages. D-AThigh leads to improved glycemia while insulin sensitivity was enhanced following resistance exercises. Thus, exercise is an effective means to elicit cardioprotection in T1DM. However, in addition to glycemia, other factors should be considered when tailoring an exercise program for T1DM patients.

Search for Boosted Dark Matter Interacting with Electrons in Super-Kamiokande

A search for boosted dark matter using 161.9 kt yr of Super-Kamiokande IV data is presented. We search for an excess of elastically scattered electrons above the atmospheric neutrino background, with a visible energy between 100 MeV and 1 TeV, pointing back to the Galactic center or the Sun. No such excess is observed. Limits on boosted dark matter event rates in multiple angular cones around the Galactic center and Sun are calculated. Limits are also calculated for a baseline model of boosted dark matter produced from cold dark matter annihilation or decay. This is the first experimental search for boosted dark matter from the Galactic center or the Sun interacting in a terrestrial detector.

Lithium Sulfonate/Carboxylate-Anchored Polyvinyl Alcohol Separators for Lithium Sulfur Batteries

A monolayer poly(vinyl alcohol) (PVA)-based separator with pendant sulfonate/carboxylate groups and compact morphology is synthesized to suppress the essential lithium polysulfide permeation in lithium sulfur batteries (LSBs). The Li⁺ transference number is significantly increased to 0.8, much higher than that of a commercial separator (0.43). The polysulfide retention is verified by idle test in a polysulfide-rich electrolyte under the internal electric field of the cell. The LSB with an additive-free electrolyte attains a Coulombic efficiency around 98% and delivered capacity of 804 mA h g^-1 at 2.5 A g^-1. After 500 cycles, it retains 901 mA h g^-1 at 1.5 A g^-1 with extra low fading rate of 0.016% per cycle. Overall, this monolayer PVA-based separator provides a facile and effective technique to assemble highly stable LSBs.

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.

Effects of Ginseng Supplementation and Endurance-Exercise in the Artery-Specific Vascular Responsiveness of Diabetic and Sedentary Rats

This study examined the effects of 12 weeks North-American ginseng supplementation, exercise training, and sedentary behavior on vascular responses in type I diabetic rats. The following hypotheses were tested: (1) ginseng supplementation would result in improved vascular responsiveness and sensitivity; (2) exercise training would result in further improvement in these vascular responses; (3) control rats with no access to exercise would show a depressed vascular response compared to control rats that were not exposed to a sedentary lifestyle. Groups: non-diabetic sedentary control (C_S), sedentary diabetic (D_S), sedentary diabetic with ginseng supplementation (D_S+GS), diabetic with ginseng supplementation and high-intensity endurance exercise (D+GS+EX), and control not exposed to sedentary behavior (C). Diabetes was induced by streptozotocin. Arteries were excised, cleaned, and mounted onto a myography system. Percent vasorelaxation to acetylcholine (ACh) (10^-8 M ACh to 10^-4 M ACh) of the carotid artery was similar in C_S (57 ± 31%), C (66 ± 35%), D_S (58 ± 36%), D+GS+Ex (71 ± 37%), and D_S+GS (64 ± 37%) (p > 0.05). Percent vasorelaxation of the aorta was smaller in C_S (23 ± 17%) compared to C (46 ± 35%), D_S (60 ± 40%), D+GS+Ex (64 ± 40%), and D_S+GS (56 ± 39%) (p < 0.05), and smaller in C compared to D+GS+Ex (p < 0.05). In the femoral, the percent vasorelaxation was reduced in D_S (18 ± 16%) compared to all the other conditions (C_S, 43 ± 22%; C, 79 ± 28%; D+GS+Ex, 55 ± 27%; D_S+GS, 45 ± 26%; p < 0.05), but larger in C compared to the other conditions (C_S, D_S, D+GS+Ex, D_S+GS; p < 0.05). Diabetes and sedentary lifestyle have detrimental effects on vascular responses that are evident in the femoral arteries of the diabetic rats. Ginseng supplementation restored the loss of sensitivity, with no added vascular protection of exercise training.

Genetic characterization of a novel group of avastroviruses in geese

As part of aetiological studies, we tested 28 samples collected from domestic geese showing enteritis and sporadic death. A novel group of avastroviruses was found in six samples. One isolate was completely sequenced, which comprised 7,148 nucleotides. Pairwise comparisons and phylogenetic analysis demonstrated that the goose astrovirus is highly divergent from all previously described avastroviruses. Our data support the view that domestic geese can be infected by astroviruses with different genetic backgrounds, and have raised a concern about the role of domestic geese as reservoirs for diverse astroviruses.

Isolation and characterization of pectolytic bacterial pathogens infecting potatoes in Nakuru County, Kenya

AIMS

Isolation and characterization of pectolytic bacteria associated with soft rot disease of potatoes in Nakuru, Kenya, to provide the basis for the development of disease control measures.

METHODS AND RESULTS

Potato tubers showing symptoms of soft rot were collected from different farms in Molo and Mau Narok regions within Nakuru county. Isolation was done using crystal violet pectate medium (CVPM). Out of the 71 isolates that showed growth on CVPM, pathogenicity tests revealed that 36 of them had the ability to macerate tissues of potato tubers. All the isolates yielded a fragment of approximately 1500 bp after 16S rDNA amplification. Using the BIOLOG microbial identification system, 20 bacterial isolates were identified as Pectobacterium carotovorum subsp. carotovorum, 7 were Pseudomonas fluorescens B while 9 were Ps. fluorescens A. Y1/Y2 primers successfully amplified pectate lyase-encoding (pel) gene, approximately 434 bp, in all the 20 P. carotovorum species. The virulence of the isolated strains to cause disease, according to pectinolytic tests, varied with change in incubation temperature of the test samples. Pectobacterium carotovorum strains were the most virulent at 30°C while disease severity due to infection by Ps. fluorescens A strains was high at 20°C compared to the other isolates.

CONCLUSION

This study reveals the identity of pectolytic bacterial species from two genera, Pectobacterium and Pseudomonas, as causative agents of potato soft rot in Nakuru, Kenya.

SIGNIFICANCE AND IMPACT OF THE STUDY

Research findings from this study will aid in developing suitable risk mitigation methods for adoption by farmers to prevent losses due to soft rot.

[Study on relationship between Set gene expression and clinical manifestations in bone marrow of patients with acute myelogenous leukemia]

Objective: To explore the expression and significance of Set gene in Acute myeloid leukemia (AML) patients , and to analyze its effect for the prognosis of AML. Methods: The level of Set gene expression was detected by real-time PCR in 59 AML patients and 20 heathy people. The mutations in C-kit 8/17 gene, NPM1 gene and FLT3-TKD/ITD gene in 59 AML patients were detected by direct sequencing. Results: The level of Set gene expression[1.41(0.41-3.31)]was significantly higher in 59 AML patients.The expression of Set gene was correlated with the percentage of marrow blasts and CR in AML patients (P=0.040, P<0.001); the CR rate of Set gene high expression group was significantly lower than that of Set gene low expression group(32.1% vs 83.9%, P=0.01). In the intermediate-risk of AML patients with chromosome karyotype analysis, the CR rate of Set gene high expression group and low expression group were 34.8% and 88.9%, and there are significantly different between two groups(P<0.001); univariate and multivariate analysis showed that Set gene high expression group correlated with poor OS[4(2-15)months]and EFS[3(2-13)months])(P=0.021, P=0.017). It suggests that the Set gene maybe one of AML independent poor prognostic marker.The level of Set gene expression did not correlate with sex, age, WBC, HGB, PLT, FAB typing, chromosomal karyotype and NPM1, C-Kit8/17, CEBPa, FLT3-ITD/TKD gene mutations in AML patients(all P>0.05). Conclusions: The level of Set gene expression in bone marrow maybe play an important role in AML. The high expression of Set gene indicates poor prognosis in AML patients.