Boost the Utilization of Dense FeN_(4) Sites for High-Performance Proton Exchange Membrane Fuel Cells

Iron-nitrogen-carbon(Fe-N-C)catalysts for the oxygen reduction reaction(ORR)in proton exchange membrane fuel cells(PEMFCs)have seriously been hindered by their poor ORR performance of Fe-N-C due to the low active site density(SD)and site utilization.Herein,we reported a melamine-assisted vapor deposition approach to overcome these hindrances.The melamine not only compensates for the loss of nitrogen caused by high-temperature pyrolysis but also effectively etches the carbon substrate,increasing the external surface area and mesoporous porosity of the carbon substrate.These can provide more useful area for subsequent vapor deposition on active sites.The prepared 0.20Mela-FeNC catalyst shows a fourfold higher SD value and site utilization than the FeNC without the treatment of melamine.As a result,0.20Mela-FeNC catalyst exhibits a high ORR activity with a half-wave potential(E_(1/2))of 0.861 V and 12-fold higher ORR mass activity than the FeNC in acidic media.As the cathode in a H_(2)-O_(2)PEMFCs,0.20Mela-FeNC catalyst demonstrates a high peak power density of 1.30 W cm^(-2),outstripping most of the reported Fe-N-C catalysts.The developed melamine-assisted vapor deposition approach for boosting the SD and utilization of Fe-N-C catalysts offers a new insight into high-performance ORR electrocatalysts.

Health Services Utilization and Health Status of Insured versus Uninsured Nigerian Children with Sickle Cell Disease

Introduction: Nigeria accounts for 150,000 infants born with the Sickle Cell Disease (SCD) every year. Children with SCD are affected by the deleterious effect of user fees which reduces affordability and utilization of health services. Evidences supported that institutionalized health insurance increases intensity of utilization. Methodology: The study was conducted at AKTH, Kano, and north-western, Nigeria. The study was retrospective comparative cross-sectional study. 100 patients were enrolled, 50 for each arm. Paediatric SCD clinic outpatients’ records and a specialty designed form containing the variables of interest were used. Data were analysed using Minitab 16. Proportions, percentages, tables, charts and chi squared test were used to compare the two groups. Result: The study found no association between the two groups in the likelihood of being insured based on age (χ2 = 1.478), gender (χ2 = 0.224) and dwellings (χ2 = 0.062). On health services utilization and insurance status, the study revealed that follow up clinic visits, unscheduled clinic visits and emergency room visits were more likely among the insured group compared to the uninsured group. While the health status and insurance status of the two groups over 12 months period showed a significant association with the insured more likely to have improved health status compared to uninsured (χ2 = 28.019, p = 0.0001). Similarly, health status and health services utilization were significantly associated with insurance status (χ2 = 12.191, p = 0.002). Conclusion: The insurance status of children with SCD is associated with their health services utilization and health status. However, age, gender and dwellings were not associated with insurance status of children with SCD. Therefore, when expanding insurance coverage (NHIS) among children with SCD considerations have to be given to increase health services utilization and resultant improvement in health status as these have the potential of reducing morbidity and mortality among children with SCD.

Gold Alloy Dental Inlay for Preventing Involuntary Body Movements Caused by Electromagnetic Waves Emitted by a Cell Phone

Cell phone and personal computer use has increased considerably in recent years, particularly in developed countries. These devices have facilitated communication on a global scale. However, there have been a number of reports of health problems related to the electromagnetic waves emitted by such electronic devices. A long list of both general and severe symptoms, including headaches, fatigue, tinnitus, dizziness, memory loss, irregular heartbeat and whole-body skin le-sions, have been reported. These are reportedly associated with the condition known as electro-magnetic hypersensitivity (EHS). This report shows how a subject’s abnormal involuntary body movements, caused by electromagnetic waves emitted by a cell phone, are prevented by placing a gold alloy inlay in the subject’s mouth. It appears that the subject’s involuntary movements are the result of balance dysregulation resulting from EHS. The subject’s various symptoms improve after the specific dental treatment. However, the underlying mechanism of the symptoms and the rea-sons why this treatment is so successful remain unknown. Further research is required to clarify these issues.

Cold stamping for AZ31B magnesium alloy sheet of cell phone house

Electric product house of magnesium alloy sheet is usually obtained by warm stamping owing to its poor plasticity and formability at room temperature.The formability of AZ31B magnesium alloy sheet can be improved by repeated unidirectional bending(RUB)process through control of(0002)basal texture.Compared with as-received sheet,the Erichsen value(IE)of the sheet underwent RUB process increases to 5.90 from 3.53 at room temperature.It is also confirmed that cell phone houses could be stamped successfully in crank press with AZ31B magnesium alloy sheets underwent RUB process.It provides an alternative to the electronics industry in the application of magnesium alloys.

Impacts of cell phone use on driving safety and drivers'perception of risk

In this study, the factors influencing phone-related driving safety and drivers＇ perceptions of cell phone usage were analyzed. A representative sample of more than 500 licensed drivers in Texas who own a cell phone was interviewed based on a well-design questionnaire. Logistic regression model showed that the impact of using cell phone on driving safety varies depending on the characteristics of drivers, such as gender, age, driving experience, and use intensity. Additionally, the results indicated that the strong determinants of phone-related hazard are different from that of phone-related accidents. Regarding the drivers＇ perception of cell phone usage, there are two key findings. First, there is no explicit belief among the drivers about whether cell phone usage impairs driving safety regardless of the drivers＇ age, gender, driving education experience etc. Second, most of drivers have not realized that cell phone use while driving would increase their perception reaction time. Based on the analysis of these results, implications of cell phone use on driving safety along with some safety countermeasures, such as selective bans and non-cell phone zones, are discussed in the paper.

A Mathematical Model for Energy Consequences of the Cell Phone Revolution

In the modern tim e,cell phone reduces the cost of important inform a-tion,p lays a cruc ial role in both fac ilitate international and dom estic trades,as well as impacts the effic iency ofm ed ical service.Consider a c ity and estim ate from ava ilab le data the numberH of house-holds,w ith m m embers each,that in the past were serviced by land lines.Now,suppose that som e land lines are rep laced by cell phones.W e model theconsequences of th is change for electric ity utilization in the c ity,during the...

Demonstration of reversible retinal ganglion cell dysfunction in inflammatory optic neuropathies utilizing pattern electroretinography

Dear Editor,I am Dr.Austin Bach from Larkin Community Hospital in South Miami,Florida,USA.I am writing to you to present three cases of inflammatory optic neuritis that was followed to resolution using pattern electroretinography（PERG）.

Is Long-Term Cell Phone Use Linked to Breast Cancer? A Review of the Evidence

Cancer of the breast is the second leading cause of cancer death among women worldwide. The majority of cancer of the breast cases (95%) is not hereditary. Can long-term cell phone use be linked to breast cancer? It is unlikely that electromagnetic radiation is involved, but it could possibly be due to the generated heat (cell phones only occasionally transmit when people are not talking on them). Therefore, is there any method or reported statistics that can be used to link the increasing breast cancer incidence with cell phone use and placement? Some young women who placed their mobile devices, including cell phones, in their bra believed that it caused their cancer because it was on the same side and in the same area their phone was adjacent to and came into contact with their skin for prolonged periods. This review highlights what is known about the link between cell phone use, which continues to increase rapidly, and breast cancer explores the association between prolonged exposure to non-ionizing radiation from cell phones and breast cancer. In conclusion, until more data are obtained concerning whether carrying a cell phone is associated with breast cancer, great care should be taken to avoid any potential risks. Strenuous efforts should be made to encourage users of cell phones to follow mobile device manufacturers’ recommendations, and if possible, to avoid skin contact until the potential risks, if there are any, are fully understood.

Effects of sports on school adaptability, resilience and cell phone addiction tendency of high school students

BACKGROUND Sport help promote healthy physical and mental development of high school students.To date,there have been few studies on the effect of sport on school adaptability,resilience and cell phone addiction tendency of high school students.AIM To explore the effects of sports on school adaptability,resilience and cell phone addiction of high school students.METHODS A stratified random sampling method was used to select 600 students from two high schools in Lhasa,and Physical Activity Rating Scale,School Adjustment Scale for High School Students,Chinese Adolescents Resilience Scale,and Mobile Phone Addiction Index were used for field questionnaire survey.RESULTS Sport was positively correlated with school adaptability and resilience(P<0.01),school adaptability was positively correlated with resilience(P<0.01)and cell phone addiction was negatively correlated with sports,school adaptability and resilience(P<0.01).The direct effect of sport on cell phone addiction was significant(P<0.001),accounting for 20.51%of the total effect.The mediating effect of school adaptability on sport and cell phone addiction was significant(P<0.001),accounting for 17.38%and 35.36%of the total effect value,respectively.School adjustment and resilience had a significant chain-mediated effect on sport and cell phone addiction(P<0.001),accounting for 26.75%of the total effect.CONCLUSION Sport affected the cell phone addiction tendency of senior high school students through the mediating effect of school adaptability and resilience,and through the chain mediation effect of both.

Potential utility of aldose reductase-deficient Schwann cells IKARS1 for the study of axonal degeneration and regeneration

Diabetic peripheral neuropathy（DPN）is one of the most common and intractable complications of diabetes mellitus.Its irritating symptoms,such as paresthesia,hyperalgesia and allodynia,can be causes of insomnia and depression;whereas its progression to more advanced stages can result in serious consequences,such as lower limb amputations and lethal arrhythmias.

Predictors and Risk Perceptions of Using Cell Phones while Driving among Young Adult Drivers

The Philippines is expecting a rise in the number of drivers that use mobile phones while driving.It is known as the“texting capital of the world”.The objectives of this study were to determine the predictors,risk perceptions and the prevalence of cell phone use while driving among trainee residents of the University of the Philippines-Philippine General Hospital.This cross-sectional study employed total enumeration.A survey was first distributed to the target population,followed by a focus group discussion.Chi-square and multiple logistic regression were used to analyze data.Included in the final analysis were 175 drivers aged 25-30 years(mean=27.90+1.34).There was no significant difference in the risk perceptions of cell phone users vs.non-users,and most perceived hands-free devices safer to use(p=0.030).The reported prevalence is 90.68%;drivers have a significant overall unsafe attitude(p=0.007),and an unsafe attitude when using handsets when driving,even when this is known to be dangerous(p=0.003).In conclusion,driving with hands-free devices was perceived to be safer,although drivers have a high overall unsafe attitude.Driving for more than two years and having an unsafe attitude were found to be significant predictors of cell phone use while driving.Countermeasures must take into account these factors when instituting behavioral modification strategies and road safety policies concerning unsafe and distracted driving.

Cell Phone’s Functions on Language Learning

With the time passing by and development of this society,almost everyone has a cell phone,we may see that cell phone as a new fifth medium after computer,having its own characters and advantages,many learners research the communica tive function of cell phone and some from the technological level.This thesis aims at trying to reveal cultural functions of culture,aiming at improve cell phone' s learning and culture functions in a more proper way.

SmartPhone类手机应用开发框架研究

通过对SmartPhone类型手机的研究与消息机制的分析,最终创建起较为通用高效的开发框架,对于后继软件开发建立了良好的开发平台.

城市绿色空间对青少年心理健康的影响:性别和手机娱乐时间的调节作用

本研究探讨了城市绿色公共空间,尤其是公园广场对青少年心理健康的影响,并着重分析了性别差异以及手机娱乐时间的调节作用。研究基于对广州市472名中学生问卷收集的数据,包括居住地、学校周边、工作日和休息日活动路径空间4种不同地理背景,建立回归模型。研究结果显示,绿色空间对青少年心理健康具有显著正向影响,居住地周围影响最大,其次是工作日活动路径、再次是休息日活动路径,学校周围影响最小。绿色空间对男生和女生的心理健康效应在不同的地理背景下表现出明显的差异,对男生在居住地周围和工作日活动路径的心理健康效应高于女生,而对女生在休息日活动空间路径的效应高于男生。手机娱乐时间的增加会抑制绿色空间的心理健康效应,对女生在居住地周围的抑制效应高于男生,对男生在休息日活动路径的抑制效应高于女生。建议可以从增加绿色空间、限制手机娱乐时间以及考虑性别敏感的干预措施3个维度促进青少年心理健康。

Windows Phone 7智能手机的取证

作为新兴的智能手机,Windows Phone手机呈稳步发展趋势,并越来越受到人们的关注。在介绍了Windows Phone 7手机的系统架构和安全模型后,就取证遇到的问题详细地描述了取证方式,探讨了如何对Windows Phone 7智能手机进行取证。通过使用原生级方法和Windows Phone SDK访问Window Phone 7内核和其他数据来获得手机的有价值信息,同时通过一系列工具来分析手机上的文件。结果表明,能够从Windows Phone 7手机中有效寻找到短信、电子邮件、社交活动等证据资料。

Woody plant cell walls:Fundamentals and utilization

Cell walls in plants,particularly forest trees,are the major carbon sink of the terrestrial ecosystem.Chemical and biosynthetic features of plant cell walls were revealed early on,focusing mostly on herbaceous model species.Recent developments in genomics,transcriptomics,epigenomics,transgenesis,and associated analytical techniques are enabling novel insights into formation of woody cell walls.Here,we review multilevel regulation of cell wall biosynthesis in forest tree species.We highlight current approaches to engineering cell walls as potential feedstock for materials and energy and survey reported field tests of such engineered transgenic trees.We outline opportunities and challenges in future research to better understand cell type biogenesis for more efficient wood cell wall modification and utilization for biomaterials or for enhanced carbon capture and storage.

晶体取向生长提升半透明钙钛矿太阳能电池的光利用效率

[目的]为提升半透明钙钛矿太阳能电池(semitransparent perovskite solar cells,ST-PSCs)的光利用效率,探究在确保透光性的同时,减轻活性层厚度变薄带来的影响.[方法]采用偶氮二甲酸二异丙酯(diisopropyl azodicarboxylate,DIAD)诱导钙钛矿前驱体PbI2的取向生长,对制备的PbI2薄膜进行形貌和光谱表征,并对相应器件进行电化学性能测试.[结果]生成的钙钛矿具备取向生长的特点,为电荷提供了在不同晶体间高速传输的通道,改善了半透明器件中因活性层厚度不足或岛状晶体生成导致的横向传输受阻,ST-PSCs器件的平均能量转换效率由14.20%上升到14.74%.同时,器件在相同的工艺条件下获得了更高的透过率,因而光利用效率从1.94%提升至2.61%.[结论]本研究针对ST-PSCs中活性层的光电性能要求,提出了有效的形貌优化与调控方法并阐明其作用机制,该方法同时提升了ST-PSCs的能量转换效率与光利用效率.

Semitransparent organic solar cells with high light utilization efficiency and color rendering index

Semitransparent organic solar cells(ST-OSCs)have garnered considerable attention as promising renewable energy technology for integrating photovoltaics into buildings.However,there is a trade-off between power conversion efficiency(PCE)and average visible transmittance(AVT),which hinders the achievement of a high light utilization efficiency(LUE).In this study,we propose a valuable method to address this challenge by replacing the transparent top electrode,Ag,with a 20 nm layer of Au.The ST-OSCs based on the 20 nm Au electrode demonstrate superior exciton extraction,more efficient charge collection,and higher color-rendering index(CRI)due to their smoother surface,higher conductivity,and enhanced visible light transmittance,resulting in a significantly higher PCE of 13.67%and an enhanced AVT of 30.17%,contributing to a high LUE of 4.15%.Additionally,optically transparent dielectric layers,applied on the front and back sides of the ST-OSCs to further boost performance,delivered an impressive LUE of 4.93%,with PCE and AVT values reaching 14.44%and 34.12%,respectively.Notably,the champion ST-OSCs also exhibited a favorable CRI value of 93.37.These achievements represent the bestperforming ST-OSCs to date with both high LUE and CRI and hold significant implications for the prospective commercialization of ST-OSCs.

燃料电池发动机气体循环方案原理分析与实验测评

为了提升燃料电池发动机能量输出效率及燃料使用率,本文对实现气体循环的三种主流方案进行原理分析,并将发电装置及气体循环装置作为整体进行针对能量利用效率的实验测评,对气体循环方案优劣进行评价。结果显示,组合泵消耗较少损耗,具备较为优异的调节性能。

Prognostic value of interim ^(18)F-FDG PET/CT in diffuse large B-cell lymphoma

Objective： Diffuse large B-cell lymphoma （DLBCL） is a heterogeneous disease. The prognostic factor currently used is not accurate enough to predict the outcomes of patients with DLBCL. The prognostic significance of interim PET/CT in DLBCL remains controversial. The aim of this study is to determine the predictive value of interim 18F-FDG PET/CT after first-line treatment in patients with DLBCL. Methods： Thirty-two patients with DLBCL underwent baseline, interim and post-treatment lSF-FDG PET/CT scans. Imaging results were analyzed for the survival of patients via software SPSS 13.0, retrospectively. Results： Thirty-one of the 32 patients were treated with R-CHOP regimen, and interim 18F-FDG PET/CT of 24 patients was performed after 2 cycles of treatment. After a median follow-up period of 16.7 months, the 2-year progression-free survival （PFS） rates were significantly different between the groups above and below SUVmax CUt-Off value of 2.5 （P=0.039）. No significant differences were found in the 2-year PFS rates if SUVm, cut-offvalues were set as 2.0 and 3.0, respectively （P=0.360; P=0.113）. Conclusions： Interim PET/CT could predict the prognosis of DLBCL patients with the SUVmax cut-off value of 2.5, but more clinical data should be concluded to confirm this conclusion.