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Activation and signaling of the p38 MAP kinase pathway 被引量:152
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作者 tyler ZARUBIN 《Cell Research》 SCIE CAS CSCD 2005年第1期11-18,共8页
The family members of the mitogen-activated protein (MAP) kinases mediate a wide variety of cellular behaviors in response to extracellular stimuli. One of the four main sub-groups, the p38 group of MAP kinases, serve... The family members of the mitogen-activated protein (MAP) kinases mediate a wide variety of cellular behaviors in response to extracellular stimuli. One of the four main sub-groups, the p38 group of MAP kinases, serve as a nexus for signal transduction and play a vital role in numerous biological processes. In this review, we highlight the known characteristics and components of the p38 pathway along with the mechanism and consequences of p38 activation. We focus on the role of p38 as a signal transduction mediator and examine the evidence linking p38 to inflammation, cell cycle, cell death, development, cell differentiation, senescence and tumorigenesis in specific cell types. Upstream and downstream components of p38 are described and questions remaining to be answered are posed. Finally, we propose several directions for future research on p38. 展开更多
关键词 p38 MAP kinase signaling pathway NEXUS inflammation DIFFERENTIATION SENESCENCE tumorigenesis.
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high-entropy silicide:(Mo_(0.2)Nb_(0.2)Ta_(0.2)Ti_(0.2)W_(0.2))Si_(2) 被引量:32
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作者 Joshua Gild Jeffrey Braun +5 位作者 Kevin Kaufmann Eduardo Marin tyler Harrington Patrick Hopkins Kenneth Vecchio Jian Luo 《Journal of Materiomics》 SCIE EI 2019年第3期337-343,共7页
A high-entropy metal disilicide,(Mo_(0.2)Nb_(0.2)Ta_(0.2)Ti_(0.2)W_(0.2))Si_(2),has been successfully synthesized.X-ray diffraction(XRD),energy dispersive X-ray spectroscopy(EDX),and electron backscatter diffraction(E... A high-entropy metal disilicide,(Mo_(0.2)Nb_(0.2)Ta_(0.2)Ti_(0.2)W_(0.2))Si_(2),has been successfully synthesized.X-ray diffraction(XRD),energy dispersive X-ray spectroscopy(EDX),and electron backscatter diffraction(EBSD)collectively show the formation of a single high-entropy silicide phase.This high-entropy(Mo_(0.2)Nb_(0.2)Ta_(0.2)Ti_(0.2)W_(0.2))Si_(2) possesses a hexagonal C40 crystal structure with ABC stacking sequence and a space group of P6222.This discovery expands the known families of high-entropy materials from metals,oxides,borides,carbides,and nitrides to a silicide,for the first time to our knowledge,as well as demonstrating that a new,non-cubic,crystal structure(with lower symmetry)can be made into highentropy phase.This(Mo_(0.2)Nb_(0.2)Ta_(0.2)Ti_(0.2)W_(0.2))Si_(2) exhibits high nanohardness of 16.7±1.9 GPa and Vickers hardness of 11.6±0.5 GPa.Moreover,it has a low thermal conductivity of 6.9±1.1Wm^(-1) K^(-1),which is approximately one order of magnitude lower than that of the widely-used tetragonal MoSi_(2) and ~1/3 of those reported values for the hexagonal NbSi_(2) and TaSi_(2) with the same crystal structure. 展开更多
关键词 High-entropy ceramics High-entropy silicide Thermal conductivity HARDNESS C40 crystal structure
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Recycling of mixed cathode lithium-ion batteries for electric vehicles: Current status and future outlook 被引量:29
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作者 tyler Or Storm WDGourley +2 位作者 Karthikeyan Kaliyappan Aiping Yu Zhongwei Chen 《Carbon Energy》 CAS 2020年第1期6-43,共38页
Worldwide trends in mobile electrification,largely driven by the popularity of electric vehicles(EVs)will skyrocket demands for lithium-ion battery(LIB)production.As such,up to four million metric tons of LIB waste fr... Worldwide trends in mobile electrification,largely driven by the popularity of electric vehicles(EVs)will skyrocket demands for lithium-ion battery(LIB)production.As such,up to four million metric tons of LIB waste from EV battery packs could be generated from 2015 to 2040.LIB recycling directly addresses concerns over longterm economic strains due to the uneven geographic distribution of resources(especially for Co and Li)and environmental issues associated with both landfilling and raw material extraction.However,LIB recycling infrastructure has not been widely adopted,and current facilities are mostly focused on Co recovery for economic gains.This incentive will decline due to shifting market trends from LiCoO2 toward cobalt-deficient and mixed-metal cathodes(eg,LiNi1/3Mn1/3Co1/3O2).Thus,this review covers recycling strategies to recover metals in mixed-metal LIB cathodes and comingled scrap comprising different chemistries.As such,hydrometallurgical processes can meet this criterion,while also requiring a low environmental footprint and energy consumption compared to pyrometallurgy.Following pretreatment to separate the cathode from other battery components,the active material is dissolved entirely by reductive acid leaching.A complex leachate is generated,comprising cathode metals(Li+,Ni2+,Mn2+,and Co2+)and impurities(Fe3+,Al3+,and Cu2+)from the current collectors and battery casing,which can be separated and purified using a series of selective precipitation and/or solvent extraction steps.Alternatively,the cathode can be resynthesized directly from the leachate. 展开更多
关键词 acid leaching comingled LIB scrap HYDROMETALLURGY NMC selective precipitation solvent extraction
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The evolution and functional diversification of animal microRNA genes 被引量:19
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作者 Na Liu Katsutomo Okamura David M tyler Michael D Phillips Wei-Jen Chung Eric C Lai 《Cell Research》 SCIE CAS CSCD 2008年第10期985-996,共12页
microRNAs (miRNAs) are an abundant class of-22 nucleotide (nt) regulatory RNAs that are pervasive in higher eukaryotic genomes. In order to fully understand their prominence in genomes, it is necessary to elucidat... microRNAs (miRNAs) are an abundant class of-22 nucleotide (nt) regulatory RNAs that are pervasive in higher eukaryotic genomes. In order to fully understand their prominence in genomes, it is necessary to elucidate the molecular mechanisms that can diversify miRNA activities. In this review, we describe some of the many strategies that allow novel miRNA functions to emerge, with particular emphasis on how miRNA genes evolve in animals. These mechanisms include changes in their sequence, processing, or expression pattern; acquisition of miRNA^* functionality or antisense processing; and de novo gene birth. The facility and versatility of miRNAs to evolve and change likely underlies how they have become dominant constituents of higher genomes. 展开更多
关键词 MICRORNA EVOLUTION SUBFUNCTIONALIZATION NEOFUNCTIONALIZATION
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Emerging role of microRNAs in lipid metabolism 被引量:18
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作者 Zhihong Yang tyler Cappello Li Wang 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2015年第2期145-150,共6页
micro RNAs(mi RNAs or mi Rs) are small non-coding RNAs that are involved in posttranscriptional regulation of their target genes in a sequence-specific manner. Emerging evidence demonstrates that mi RNAs are critical ... micro RNAs(mi RNAs or mi Rs) are small non-coding RNAs that are involved in posttranscriptional regulation of their target genes in a sequence-specific manner. Emerging evidence demonstrates that mi RNAs are critical regulators of lipid synthesis, fatty acid oxidation and lipoprotein formation and secretion. Dysregulation of mi RNAs disrupts gene regulatory network, leading to metabolic syndrome and its related diseases. In this review, we introduced epigenetic and transcriptional regulation of mi RNAs expression. We emphasized on several representative mi RNAs that are functionally involved into lipid metabolism, including mi R-33/33 n, mi R122, mi R27a/b, mi R378/378 n, mi R-34 a and mi R-21.Understanding the function of mi RNAs in lipid homeostasis may provide potential therapeutic strategies for fatty liver disease. 展开更多
关键词 Lipid metabolism MICRORNAS Nuclear receptors
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Artificial intelligence in gastrointestinal endoscopy:The future is almost here 被引量:18
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作者 Muthuraman Alagappan Jeremy R Glissen Brown +1 位作者 Yuichi Mori tyler M Berzin 《World Journal of Gastrointestinal Endoscopy》 CAS 2018年第10期239-249,共11页
Artificial intelligence(AI) enables machines to provide unparalleled value in a myriad of industries and applications. In recent years, researchers have harnessed artificial intelligence to analyze large-volume, unstr... Artificial intelligence(AI) enables machines to provide unparalleled value in a myriad of industries and applications. In recent years, researchers have harnessed artificial intelligence to analyze large-volume, unstructured medical data and perform clinical tasks, such as the identification of diabetic retinopathy or the diagnosis of cutaneous malignancies. Applications of artificial intelligence techniques, specifically machine learning and more recently deep learning, are beginning to emerge in gastrointestinal endoscopy. The most promising of these efforts have been in computeraided detection and computer-aided diagnosis of colorectal polyps, with recent systems demonstrating high sensitivity and accuracy even when compared to expert human endoscopists. AI has also been utilized to identify gastrointestinal bleeding, to detect areas of inflammation, and even to diagnose certain gastrointestinal infections. Future work in the field should concentrate on creating seamless integration of AI systems with current endoscopy platforms and electronic medical records, developing training modules to teach clinicians how to use AI tools, and determining the best means for regulation and approval of new AI technology. 展开更多
关键词 Artificial intelligence Machine learning Gastrointestinal endoscopy COMPUTER-ASSISTED decision making COMPUTER-AIDED detection COLONIC POLYPS COLONOSCOPY COMPUTER-AIDED diagnosis Colorectal ADENOCARCINOMA
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Magnetic anchor guidance for endoscopic submucosal dissection and other endoscopic procedures 被引量:15
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作者 Mohamed Mortagy Neal Mehta +5 位作者 Mansour A Parsi Seiichiro Abe tyler Stevens John J Vargo Yutaka Saito Amit Bhatt 《World Journal of Gastroenterology》 SCIE CAS 2017年第16期2883-2890,共8页
Endoscopic submucosal dissection(ESD) is a wellestablished, minimally invasive treatment for superficial neoplasms of the gastrointestinal tract. The universal adoption of ESD has been limited by its slow learning cur... Endoscopic submucosal dissection(ESD) is a wellestablished, minimally invasive treatment for superficial neoplasms of the gastrointestinal tract. The universal adoption of ESD has been limited by its slow learning curve, long procedure times, and high risk of complications. One technical challenge is the lack of a second hand that can provide traction, as in conventional surgery. Reliable tissue retraction that exposes the submucosal plane of dissection would allow for safer and more efficient dissection. Magnetic anchor guided endoscopic submucosal dissection(MAGESD) has potential benefits compared to other current traction methods. MAG-ESD offers dynamic tissue retraction independent of the endoscope mimicking a surgeon's "second hand". Two types of magnets can be used: electromagnets and permanent magnets. In this article we review the MAG-ESD technology, published work and studies of magnets in ESD. We also review the use of magnetic anchor guidance systems in natural orifice transluminal endoscopic surgery and the idea of magnetic non-contact retraction using surface ferromagentization. We discuss the current limitations, the future potential of MAG-ESD and the developments needed for adoption of this technology. 展开更多
关键词 ENDOSCOPIC submucosal dissection Gastric CANCER MAGNETIC ANCHOR GUIDANCE Esophageal CANCER Magnets Traction Natural orifice TRANSLUMINAL ENDOSCOPIC surgery
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Genetic factors that affect nonalcoholic fatty liver disease: A systematic clinical review 被引量:13
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作者 tyler J Severson Siddesh Besur Herbert L Bonkovsky 《World Journal of Gastroenterology》 SCIE CAS 2016年第29期6742-6756,共15页
AIM: To investigate roles of genetic polymorphisms in non-alcoholic fatty liver disease (NAFLD) onset, severity, and outcome through systematic literature review.METHODS: The authors conducted both systematic and spec... AIM: To investigate roles of genetic polymorphisms in non-alcoholic fatty liver disease (NAFLD) onset, severity, and outcome through systematic literature review.METHODS: The authors conducted both systematic and specific searches of PubMed through December 2015 with special emphasis on more recent data (from 2012 onward) while still drawing from more historical data for background. We identified several specific genetic polymorphisms that have been most researched and, at this time, appear to have the greatest clinical significance on NAFLD and similar hepatic diseases. These were further investigated to assess their specific effects on disease onset and progression and the mechanisms by which these effects occur.RESULTS: We focus particularly on genetic polymorphisms of the following genes: PNPLA3, particularly the p. I148M variant, TM6SF2, particularly the p. E167K variant, and on variants in FTO, LIPA, IFN&#x003bb;4, and iron metabolism, specifically focusing on HFE, and HMOX-1. We discuss the effect of these genetic variations and their resultant protein variants on the onset of fatty liver disease and its severity, including the effect on likelihood of progression to cirrhosis and hepatocellular carcinoma. While our principal focus is on NAFLD, we also discuss briefly effects of some of the variants on development and severity of other hepatic diseases, including hepatitis C and alcoholic liver disease. These results are briefly discussed in terms of clinical application and future potential for personalized medicine.CONCLUSION: Polymorphisms and genetic factors of several genes contribute to NAFLD and its end results. These genes hold keys to future improvements in diagnosis and management. 展开更多
关键词 Genetic polymorphisms Non-alcoholic fatty liver disease Non-alcoholic steatohepatitis PNPLA3 TM6SF2 FTO CIRRHOSIS Iron metabolism
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Discovery of high-entropy ceramics via machine learning 被引量:13
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作者 Kevin Kaufmann Daniel Maryanovsky +7 位作者 William M.Mellor Chaoyi Zhu Alexander S.Rosengarten tyler J.Harrington Corey Oses Cormac Toher Stefano Curtarolo Kenneth S.Vecchio 《npj Computational Materials》 SCIE EI CSCD 2020年第1期1323-1331,共9页
Although high-entropy materials are attracting considerable interest due to a combination of useful properties and promising applications,predicting their formation remains a hindrance for rational discovery of new sy... Although high-entropy materials are attracting considerable interest due to a combination of useful properties and promising applications,predicting their formation remains a hindrance for rational discovery of new systems.Experimental approaches are based on physical intuition and/or expensive trial and error strategies.Most computational methods rely on the availability of sufficient experimental data and computational power.Machine learning(ML)applied to materials science can accelerate development and reduce costs.In this study,we propose an ML method,leveraging thermodynamic and compositional attributes of a given material for predicting the synthesizability(i.e.,entropy-forming ability)of disordered metal carbides. 展开更多
关键词 CERAMICS ENTROPY attracting
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耳鸣对患者日常影响调查及耳鸣活动问卷的信度检验 被引量:12
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作者 潘滔 Richard tyler +3 位作者 宋昱 王宇 柯嘉 马芙蓉 《中国耳鼻咽喉头颈外科》 北大核心 2011年第12期667-670,共4页
目的调查耳鸣对患者日常影响,为耳鸣咨询提供参考和依据。检验耳鸣活动问卷(tinnitus activity questionnaire,TAQ)的可信度(reliability),为TAQ的应用提供依据。方法我院2008~2010年门诊耳鸣患者,耳鸣持续时间长于3个月者195例接受TA... 目的调查耳鸣对患者日常影响,为耳鸣咨询提供参考和依据。检验耳鸣活动问卷(tinnitus activity questionnaire,TAQ)的可信度(reliability),为TAQ的应用提供依据。方法我院2008~2010年门诊耳鸣患者,耳鸣持续时间长于3个月者195例接受TAQ调查,以了解耳鸣对患者日常生活的影响。对195例耳鸣患者的耳鸣活动问卷进行因子分析(factor analysis)。结果耳鸣对患者的影响包括:TAQ得分:情绪状况47,注意力27,听力28,睡眠32。情绪状态是耳鸣对患者影响的最主要方面。对TAQ问卷因子分析的结果得出4个因子:分别解释的变异百分比为47.2%、11.9%、6.3%、5.2%,累计解释总体变异70.5%。因子分析的结果比较接近问卷设计的注意力、睡眠、听力、情绪4个方面,但是符合性并不完善。结论耳鸣对患者日常影响的注意力、睡眠、听力、情绪4个方面中情绪是主要的影响方面,耳鸣咨询应侧重该方面。TAQ因子分析结果比较接近问卷设计本身,具有较好的可信度。 展开更多
关键词 耳鸣 问卷调查 问卷可信度
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Stripe Rust Effector PstGSRE1 Disrupts Nuclear Localization of ROS-Promoting Transcription Factor TaLOL2 to Defeat ROS-Induced Defense in Wheat 被引量:12
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作者 Tuo Qi Jia Guo +6 位作者 Peng Liu Fuxin He Cuiping Wan Md Ashraful Islam Brett M.tyler Zhensheng Kang Jun Guo 《Molecular Plant》 SCIE CAS CSCD 2019年第12期1624-1638,共15页
Puccinia striiformis f.sp.tritici(Pst),a biotrophic plant pathogen,secretes numerous effectors to modulate host defense systems.Understanding the molecular mechanisms by which Pst effectors regulate wheat immunity is ... Puccinia striiformis f.sp.tritici(Pst),a biotrophic plant pathogen,secretes numerous effectors to modulate host defense systems.Understanding the molecular mechanisms by which Pst effectors regulate wheat immunity is of great importance for the development of novel strategies for durable control of stripe rust.In this study,we identified a glycine-serine-rich effector gene,PstGSRE1,which is highly induced dur-ing early infection.Transgenic expression of PstGSRE1 RNAi constructs in wheat significantly reduced virulence of Pst and increased H2O2 accumulation in wheat.PstGSRE1 was shown to target the reactive ox-ygen species(ROS)-associated transcription factor TaLOL2,a positive regulator of wheat immunity.PstGSRE1 disrupted nuclear localization of TaLOL2 and suppressed ROS-mediated cell death induced by TaLOL2,thus compromising host immunity.This work reveals a previously unrecognized strategy whereby rust fungi exploit the PstGSRE1 effector to defeat ROS-associated plant defense by modulating the subcellular compartment of a host immune regulator and facilitate pathogen infection. 展开更多
关键词 host-induced gene silencing EFFECTOR glycine-serine-rich transcription factor PUCCINIA STRIIFORMIS f.sp.tritici reactive oxygen species
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溪洛渡水库水温日变化的测量与分析 被引量:9
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作者 谢奇珂 刘昭伟 +2 位作者 陈永灿 陈啸 Kenneth tyler Werk 《水科学进展》 EI CAS CSCD 北大核心 2018年第4期523-536,共14页
溪洛渡等河道型水库具有库容大且径流量大的特点,热动力过程和水温分布迥异于天然河流或湖泊。通过温度链对溪洛渡水库坝前水温进行长期高频监测,选取升温期和降温期典型时段,分析表层水温的昼夜变化和温跃层的内波现象;计算表面热交换... 溪洛渡等河道型水库具有库容大且径流量大的特点,热动力过程和水温分布迥异于天然河流或湖泊。通过温度链对溪洛渡水库坝前水温进行长期高频监测,选取升温期和降温期典型时段,分析表层水温的昼夜变化和温跃层的内波现象;计算表面热交换,并分析其对水温变化的影响。结果表明:水面混合层在水面热交换的控制下周期性出现和消失;在升温期水面吸热对于变温层升温过程有重要影响;在降温期,水面失热驱动了垂向混合,入流降温形成侵入流,共同控制变温层的降温过程;温跃层中24 h周期的内波形成与出流日调节有直接因果关系。与实测数据计算的水面热通量相比,采用气象站日值数据的溪洛渡数值模型的模拟值偏小。 展开更多
关键词 水温 水面热交换 日变化 溪洛渡水库
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Effects of alkaline-electrolyzed and hydrogen-rich water,in a high-fat-diet nonalcoholic fatty liver disease mouse model 被引量:10
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作者 Karen Jackson Noa Dressler +3 位作者 Rotem S Ben-Shushan Ari Meerson tyler W LeBaron Snait Tamir 《World Journal of Gastroenterology》 SCIE CAS 2018年第45期5095-5108,共14页
AIM To identify the effect of hydrogen-rich water(HRW) and electrolyzed-alkaline water(EAW) on high-fat-induced non-alcoholic fatty acid disease in mice.METHODS Mice were divided into four groups:(1) Regular diet(RD)/... AIM To identify the effect of hydrogen-rich water(HRW) and electrolyzed-alkaline water(EAW) on high-fat-induced non-alcoholic fatty acid disease in mice.METHODS Mice were divided into four groups:(1) Regular diet(RD)/regular water(RW);(2) high-fat diet(HFD)/RW;(3) RD/EAW; and(4) HFD/EAW. Weight and body composition were measured. After twelve weeks, animals were sacrificed, and livers were processed for histology and reverse-transcriptase polymerase chain reaction. A similar experiment was performed using HRW to determine the influence and importance of molecular hydrogen(H2) in EAW. Finally, we compared the response of hepatocytes isolated from mice drinking HRW or RW to palmitate overload.RESULTS EAW had several properties important to the study:(1) pH = 11;(2) oxidation-reduction potential of-495 mV; and(3) H2 = 0.2 mg/L. However, in contrast to other studies, there were no differences between the groups drinking EAW or RW in either the RD or HFD groups. We hypothesized that the null result was due to low H2 concentrations. Therefore, we evaluated the effects of RW and low and high HRW concentrations(L-HRW = 0.3 mg H2/L and H-HRW = 0.8 mg H2/L, respectively) in mice fed an HFD. Compared to RW and L-HRW, H-HRW resulted in a lower increase in fat mass(46% vs 61%), an increase in lean body mass(42% vs 28%), and a decrease in hepatic lipid accumulation(P < 0.01). Lastly, exposure of hepatocytes isolated from mice drinking H-HRW to palmitate overload demonstrated a protective effect from H2 by reducing hepatocyte lipid accumulation in comparison to mice drinking regular water.CONCLUSION H2 is the therapeutic agent in electrolyzed-alkaline water and attenuates HFD-induced nonalcoholic fatty liver disease in mice. 展开更多
关键词 Hydrogen-rich-water NONALCOHOLIC fatty liver disease ALKALINE WATER Metabolic syndrome Molecular HYDROGEN HIGH-FAT DIET
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Tricuspid mass-curious case of Li-Fraumeni syndrome: A case report 被引量:4
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作者 tyler Huffaker Stella Pak +1 位作者 Anum Asif Prince Otchere 《World Journal of Clinical Cases》 SCIE 2024年第11期1936-1939,共4页
BACKGROUND Li-Fraumeni syndrome(LFS)is a rare autosomal dominant cancer-predisposing syndrome,which can manifest as a polymorphic spectrum of malignancies.LFS is associated with an early onset in life,with the majorit... BACKGROUND Li-Fraumeni syndrome(LFS)is a rare autosomal dominant cancer-predisposing syndrome,which can manifest as a polymorphic spectrum of malignancies.LFS is associated with an early onset in life,with the majority of cases occurring prior to the age of 46.Notwithstanding the infrequency of primary cardiac tumors,it behooves clinicians to remain vigilant in considering the differential diagnosis of such tumors in LFS patients who present with a cardiac mass.This is due to the markedly elevated risk for malignancy in this particular population,far surpassing that of the general populace.CASE SUMMARY Herein,we present a case of a 30-year-old female with LFS who was found to have a tricuspid valve leaflet mass.CONCLUSION This case exemplifies valuable learning points in the diagnostic approach for this exceptionally rare patient population. 展开更多
关键词 Li-Fraumeni syndrome Cardiac mass Intracardiac thrombus Transesophageal echocardiogram Cardiac magnetic resonance imaging Case report
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基于归纳式学习法的通勤交通满意度指标研究 被引量:9
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作者 赵明宇 孙立军 +2 位作者 tyler Nick 兰成 兰成 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2011年第9期1303-1306,1344,共5页
以评价通勤者对交通系统满意度为目的,建立通勤交通满意度指标.以问卷形式采集数据,采用归纳式学习方法,分析通勤者满意度等级与通勤时间之间的相关信息,得到以大于0.5证据权的出行时间区间为代表值的满意度指标.其中,通勤时间区间10~3... 以评价通勤者对交通系统满意度为目的,建立通勤交通满意度指标.以问卷形式采集数据,采用归纳式学习方法,分析通勤者满意度等级与通勤时间之间的相关信息,得到以大于0.5证据权的出行时间区间为代表值的满意度指标.其中,通勤时间区间10~30min为出行者最满意的通勤时间代表值.此结论从一个角度说明交通出行行为具有"可达性"与"移动性"的双重价值. 展开更多
关键词 通勤交通 满意度指标 归纳式学习
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完美数及其相关问题
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作者 蔡天新 tyler ROSS 《数学进展》 CSCD 北大核心 2024年第4期673-689,共17页
完美数问题是最古老的数学问题之一,可能来源于古希腊的毕达哥拉斯学派,被意大利当代数学家奥迪弗雷迪列为面向21世纪的“四大数学难题”之首.本文对古老的完美数问题及相关的梅森素数进行综述,尤其是对其拓展为平方完美数、立方完美数... 完美数问题是最古老的数学问题之一,可能来源于古希腊的毕达哥拉斯学派,被意大利当代数学家奥迪弗雷迪列为面向21世纪的“四大数学难题”之首.本文对古老的完美数问题及相关的梅森素数进行综述,尤其是对其拓展为平方完美数、立方完美数及S-完美数以后所产生的问题进行了综述. 展开更多
关键词 完美数 平方完美数 立方完美数 S-完美数
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Cooling High Power Dissipating Artificial Intelligence (AI) Chips Using Refrigerant
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作者 Waheeb Mukatash Hussameddine Kabbani +4 位作者 Jochem Marc Massalt Matthew Moscoso Merari Mejia Robles tyler Yang Charlie Nino 《Journal of Electronics Cooling and Thermal Control》 2024年第2期35-49,共15页
High power dissipating artificial intelligence (AI) chips require significant cooling to operate at maximum performance. Current trends regarding the integration of AI, as well as the power/cooling demands of high-per... High power dissipating artificial intelligence (AI) chips require significant cooling to operate at maximum performance. Current trends regarding the integration of AI, as well as the power/cooling demands of high-performing server systems pose an immense thermal challenge for cooling. The use of refrigerants as a direct-to-chip cooling method is investigated as a potential cooling solution for cooling AI chips. Using a vapor compression refrigeration system (VCRS), the coolant temperature will be sub-ambient thereby increasing the total cooling capacity. Coupled with the implementation of a direct-to-chip boiler, using refrigerants to cool AI server systems can materialize as a potential solution for current AI server cooling demands. In this study, a comparison of 8 different refrigerants: R-134a, R-153a, R-717, R-508B, R-22, R-12, R-410a, and R-1234yf is analyzed for optimal performance. A control theoretical VCRS model is created to assess variable refrigerants under the same operational conditions. From this model, the coefficient of performance (COP), required mass flow rate of refrigerant, work required by the compressor, and overall heat transfer coefficient is determined for all 8 refrigerants. Lastly, a comprehensive analysis is provided to determine the most optimal refrigerants for cooling applications. R-717, commonly known as Ammonia, was found to have the highest COP value thus proving to be the optimal refrigerant for cooling AI chips and high-performing server applications. 展开更多
关键词 Artificial Intelligence Thermal Control Server Systems Vapor Compression Refrigeration Cycle Server Cooling
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教师主观幸福感量表的中文修订
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作者 谢家树 柳剑锋 +5 位作者 林欣欣 Chunyan Yang 魏宇民 蔺璐璐 Quennie Dong tyler L.Renshaw 《中国临床心理学杂志》 CSCD 北大核心 2024年第4期887-892,共6页
目的:检验教师主观幸福感量表(Teacher Subjective Well-being Questionnaire,TSWQ)中文修订版信度、效度及其跨教师性别、跨任教学段的测量等值性。方法:应用中文版TSWQ对来自全国9省份56所中学的1463名教师进行测量,以中小学教师职业... 目的:检验教师主观幸福感量表(Teacher Subjective Well-being Questionnaire,TSWQ)中文修订版信度、效度及其跨教师性别、跨任教学段的测量等值性。方法:应用中文版TSWQ对来自全国9省份56所中学的1463名教师进行测量,以中小学教师职业倦怠量表和特拉华校园氛围量表-教工卷为效标工具,一个月后随机抽取55名教师进行重测。结果:(1)验证性因素分析结果支持一阶二因子模型。(2)中文版TSWQ总分与教师校园氛围感知、个人成就感显著正相关(r=0.465,P<0.01;r=0.416,P<0.01),与情绪衰竭、非人性化显著负相关(r=-0.226,P<0.01;r=-0.232,P<0.01)。(3)中文版TSWQ总量表的Cronbach’sα系数为0.898,四周后的重测信度为0.813。(4)多组验证性因素分析结果显示,中文版TSWQ跨性别和跨任教学段的测量等值性假设成立。(5)在教师主观幸福感量表的教学效能感维度存在显著性别差异,男教师教学效能感优于女教师。结论:中文版TSWQ信度与效度良好,可在不同教师性别、任教学段之间进行跨组比较,是研究我国教师主观幸福感的可靠工具。 展开更多
关键词 主观幸福感 心理健康 信度 效度 测量等值性 教师
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Increased Mortality Risk in Children with Fetal Alcohol Spectrum Disorders: A Scoping Review
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作者 Devin Evavold tyler Mueller +2 位作者 Erika Johnson Marilyn G. Klug Larry Burd 《Open Journal of Pediatrics》 2024年第4期754-766,共13页
Objective: Fetal Alcohol Spectrum Disorders (FASDs) are common, often undiagnosed, lifelong developmental disorders that result from prenatal alcohol exposure. FASD is present at birth and typically identified around ... Objective: Fetal Alcohol Spectrum Disorders (FASDs) are common, often undiagnosed, lifelong developmental disorders that result from prenatal alcohol exposure. FASD is present at birth and typically identified around seven years of age. The most severe outcome in cases of FASD is mortality. The purpose of this scoping review is to 1) use a systematic review to provide an estimated mortality proportion for children with FASD, and 2) update a study published in 2014 by reviewing published reports of mortality in individuals diagnosed with FASD. Method: A search of PubMed, CINAHL, and Google Scholar for reports published between 2013 and 2023 on mortality in individuals with FASD. Results: Three population-based studies have reported on all-cause mortality rates, finding a combined mortality rate of 10.9%, a 2.63 fold (95% CI: 2.61 to 2.65) increase in mortality risk over the general population. Since 2016, this review identified only eight new cases meeting the study inclusion criteria. The reported causes of death were five cases of pneumonia, and one case each of failure to thrive and dehydration, intestinal dilatation and asphyxiation caused by overeating due to pica, and acute gastric volvulus. Discussion: While current research suggests a diagnosis of FASD is associated with a 2.6-fold increase in mortality risk, this is likely an underestimation, as most cases of FASD-related mortality go unreported. Globally, about 1 new case is reported every 15 months. However, in the United States alone, between 1752 to 4400 FASD related deaths occur annually. Our review suggests that FASD is rarely identified as a causal or contributing factor in deaths of children and adolescents, resulting in a substantial undercount of FASD-related deaths. Increased attention to the role of FASD in infant and child mortality case reviews, child death review committee reports, and mortality reviews is needed. 展开更多
关键词 Fetal Alcohol Spectrum Disorders MORTALITY Birth Defects DEATH EXPOSURE PNEUMONIA
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Is a Mini-Screen for Fetal Alcohol Spectrum Disorder Feasible?
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作者 tyler Mueller Devin Evavold +2 位作者 June-Yung Kim Marilyn G. Klug Larry Burd 《Open Journal of Pediatrics》 2024年第4期767-781,共15页
Background: Fetal Alcohol Spectrum Disorders (FASDs) are a global public health concern with lifelong consequences for affected individuals. Recent prevalence studies suggest FASD prevalence rates range from 1-5% amon... Background: Fetal Alcohol Spectrum Disorders (FASDs) are a global public health concern with lifelong consequences for affected individuals. Recent prevalence studies suggest FASD prevalence rates range from 1-5% among school age children. Most people with FASD are not correctly diagnosed and inadequate screening to identify patients with increased risk may contribute to under-diagnosis. This study developed a 10-item screening tool for FASD and examined its feasibility. Methods: The sample consisted of 355 children who had been evaluated at an FASD clinic. Data from the 33-item Alcohol Related Neurodevelopmental Disorder Behavioral Checklist was used to develop a brief FASD screen by comparing the changes in Cronbach’s alpha for different combinations of items. The validity of the brief scale was then further examined using receiving operating characteristic analyses. Results: The 10-item screen demonstrated acceptable sensitivity, specificity, and accuracy to identify children at high risk for FASD. The percentage correctly classified was 91.3 and the area under the receiving operating characteristic curve was 0.971. Conclusions: This feasibility study demonstrated that a screen for FASD consisting of 10 items with yes or no responses can be completed in 3 - 4 minutes. The tool is brief, with a low administration burden and has acceptable epidemiologic performance characteristics including accuracy. Future research should examine the performance of this tool when used in larger, community-based populations where screening for FASD would be appropriate. 展开更多
关键词 Fetal Alcohol Spectrum Disorders (FASDs) CHILDREN SCREENING PREVALENCE
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