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Zhao Guo,1,* Haoyun Song,1,* Yingxia Tian,2,* Jie Xu,3 Guokun Zhang,1 Yanan Guo,1 Rong Shen,1 Degui Wang1 1Department of Anatomy and Histology, Lanzhou University School of Basic Medical Sciences, Lanzhou, 730000, People’s Republic of China; 2Department of Internal Medicine, Gansu Provincial Academic Institute for Medical Research, Lanzhou, 730050, People’s Republic of China; 3Cuiying Biomedical Research Center, Lanzhou University Second Hospital, Lanzhou, Gansu, 730030, People’s Republic of China*These authors contributed equally to this workCorrespondence: Degui Wang; Rong Shen, Department of Anatomy and Histology, Lanzhou University School of Basic Medical Sciences, Lanzhou, 730000, People’s Republic of China, Tel +86 13893609120 ; +86 13909483373, Fax +86 931 8915023, Email wangdegui@lzu.edu.cn; shenr@lzu.edu.cnBackground: The evident side effects and decreased drug sensitivity significantly restrict the use of chemotherapy. However, nanoparticles based on biomaterials are anticipated to address this challenge.Methods: Through bioinformatics analysis and colon cancer samples, we initially investigated the expression level of RNF8 in colon cancer. Next, we constructed nanocarrier for delivering siRNF8 based on DNA tetrahedron (si-Tet), and Doxorubicin (DOX) was further intercalated into the DNA structure (si-DOX-Tet) for combination therapy. Further, the effects and mechanism of RNF8 inhibition on the sensitivity of colon cancer cells to DOX chemotherapy have also been studied.Results: RNF8 expression was increased in colon cancer. Agarose gel electrophoresis, transmission electron microscopy, and size distribution and potential analysis confirmed the successful preparation of the two nanoparticles, with particle sizes of 10.29 and 37.29 nm, respectively. Fluorescence imaging reveals that the carriers can be internalized into colon cancer cells and escape from lysosomes after 12 hours of treatment, effectively delivering si

Fulvia fulva and Dothistroma septosporum are closely related apoplastic pathogens with similar lifestyles but different hosts: F. fulva is a pathogen of tomato, whilst D. septosporum is a pathogen of pine trees. In 2012, the first genome sequences of these pathogens were published, with F. fulva and D. septosporum having highly fragmented and near-complete assemblies, respectively. Since then, significant advances have been made in unravelling their genome architectures. For instance, the genome of F. fulva has now been assembled into 14 chromosomes, 13 of which have synteny with the 14 chromosomes of D. septosporum, suggesting these pathogens are even more closely related than originally thought. Considerable advances have also been made in the identification and functional characterization of virulence factors (e.g., effector proteins and secondary metabolites) from these pathogens, thereby providing new insights into how they promote host colonization or activate plant defence responses. For example, it has now been established that effector proteins from both F. fulva and D. septosporum interact with cell-surface immune receptors and co-receptors to activate the plant immune system. Progress has also been made in understanding how F. fulva and D. septosporum have evolved with their host plants, whilst intensive research into pandemics of Dothistroma needle blight in the Northern Hemisphere has shed light on the origins, migration, and genetic diversity of the global D. septosporum population. In this review, we specifically summarize advances made in our understanding of the F. fulva-tomato and D. septosporum-pine pathosystems over the last 10 years.

Scab, caused by the biotrophic fungal pathogen Venturia inaequalis, is the most economically important disease of apples. During infection, V. inaequalis colonizes the subcuticular host environment, where it develops specialized infection structures called runner hyphae and stromata. These structures are thought to be involved in nutrient acquisition and effector (virulence factor) delivery, but also give rise to conidia that further the infection cycle. Despite their importance, very little is known about how these structures are differentiated. Likewise, nothing is known about how these structures are protected from host defenses or recognition by the host immune system. To better understand these processes, we first performed a glycosidic linkage analysis of sporulating tubular hyphae from V. inaequalis developed in culture. This analysis revealed that the V. inaequalis cell wall is mostly composed of glucans (44%) and mannans (37%), whereas chitin represents a much smaller proportion (4%). Next, we used transcriptomics and confocal laser scanning microscopy to provide insights into the cell wall carbohydrate composition of runner hyphae and stromata. These analyses revealed that, during subcuticular host colonization, genes of V. inaequalis putatively associated with the biosynthesis of immunogenic carbohydrates, such as chitin and b-1,6-glucan, are downregulated relative to growth in culture, while on the surface of runner hyphae and stromata, chitin is deacetylated to the less-immunogenic carbohydrate chitosan. These changes are anticipated to enable the subcuticular differentiation of runner hyphae and stromata by V. inaequalis, as well as to protect these structures from host defenses and recognition by the host immune system. IMPORTANCE Plant-pathogenic fungi are a major threat to food security. Among these are subcuticular pathogens, which often cause latent asymptomatic infections, making them difficult to control. A key feature of these pathogens is thei, QC 20230823

Xuelun Wu,1 Furui Zhai,2 Ailing Chang,1 Jing Wei,1 Yanan Guo,1 Jincheng Zhang1 1Department of Endocrinology, Cangzhou Central Hospital, Cangzhou City, Hebei Province, People’s Republic of China; 2Gynecological Clinic, Cangzhou Central Hospital, Cangzhou City, Hebei Province, People’s Republic of ChinaCorrespondence: Xuelun Wu, Department of Endocrinology, Cangzhou Central Hospital, 16 Xinhua West Road, Cangzhou City, Hebei Province, People’s Republic of China, Tel +86-317-2075501, Email wxl20112285@163.comPurpose: Diagnosing osteoporosis in T2DM based on bone mineral density (BMD) remains challenging. We sought to develop prediction models employing machine learning algorithms for use as screening instruments for osteoporosis in T2DM patients.Patients and Methods: Data were collected from 433 participants and analyzed using nine categorical machine learning algorithms to select features based on demographic and clinical variables. Multiple classification models were compared using the area under the receiver operating characteristic curve (ROC-AUC), accuracy, sensitivity, specificity, the average precision (AP), precision, F1 score, precision-recall curves, calibration plots, and decision curve analysis (DCA) to determine the best model. In addition, 5-fold cross-validation was utilized to optimize the model, followed by an evaluation of feature significance using Shapley Additive exPlanations (SHAP). Using latent class analysis (LCA), distinct subpopulations were identified by constructing several discrete clusters.Results: In this study, nine feature variables were identified to construct predictive models for osteoporosis in individuals with T2DM. The machine learning algorithms achieved an AP range of 0.444– 1.000. The XGBoost model was selected as the final prediction model with an AUROC of 0.940 in the training set, 0.772 in the validation set for 5-fold cross-validation, and 0.872 in the test set. Using SHAP methodology, 25(OH)D was identified as the

Fulvia fulva and Dothistroma septosporum are closely related apoplastic pathogens with similar lifestyles but different hosts: F. fulva is a pathogen of tomato, whilst D. septosporum is a pathogen of pine trees. In 2012, the first genome sequences of these pathogens were published, with F. fulva and D. septosporum having highly fragmented and near-complete assemblies, respectively. Since then, significant advances have been made in unravelling their genome architectures. For instance, the genome of F. fulva has now been assembled into 14 chromosomes, 13 of which have synteny with the 14 chromosomes of D. septosporum, suggesting these pathogens are even more closely related than originally thought. Considerable advances have also been made in the identification and functional characterization of virulence factors (e.g., effector proteins and secondary metabolites) from these pathogens, thereby providing new insights into how they promote host colonization or activate plant defence responses. For example, it has now been established that effector proteins from both F. fulva and D. septosporum interact with cell-surface immune receptors and co-receptors to activate the plant immune system. Progress has also been made in understanding how F. fulva and D. septosporum have evolved with their host plants, whilst intensive research into pandemics of Dothistroma needle blight in the Northern Hemisphere has shed light on the origins, migration, and genetic diversity of the global D. septosporum population. In this review, we specifically summarize advances made in our understanding of the F. fulva–tomato and D. septosporum–pine pathosystems over the last 10 years.

Quantum computing has recently emerged as a promising computing paradigm for many application domains. However, the size of quantum circuits that can run with high fidelity is constrained by the limited quantity and quality of physical qubits. Recently proposed schemes, such as wire cutting and qubit reuse, mitigate the problem but produce sub-optimal results as they address the problem individually. In addition, gate cutting, an alternative circuit-cutting strategy, has not been fully explored in the field. In this paper, we propose IQRC, an integrated approach that exploits qubit reuse and circuit cutting (including wire cutting and gate cutting) to run large circuits on small quantum computers. Circuit-cutting techniques introduce non-negligible post-processing overhead, which increases exponentially with the number of cuts. IQRC exploits qubit reuse to find better cutting solutions to minimize the cut numbers and thus the post-processing overhead. Our evaluation results show that on average we reduce the number of cuts by 34\% and additional reduction when considering gate cuts.

During infectious disease outbreaks, early warning is crucial to prevent and control the further spread of the disease. While the different waves of the Covid-19 pandemic have demonstrated the need for continued compliance, little is known about the impact of warning messages and risk perception on individual behavior in public health emergencies. To address this gap, this paper uses data from the second wave of Covid-19 in China to analyse how warning information influences preventive behavior through four categories risk perception and information interaction. Drawing on the protective action decision model (PADM) and the social amplification of risk framework (SARF), risk warning information (content, channel, and type), risk perception (threat perception, hazard- and resource-related preparedness behavior perception and stakeholder perception), information interaction, and preparedness behavior intention are integrated into a comprehensive model. To test our model, we run a survey with 724 residents in Northern China. The results show that hazard-related preparedness behavior perception and stakeholder perception act as mediators between warning and preventive action. Stakeholder perception had much stronger mediating effects than the hazard-related attributes. In addition, information interaction is effective in increasing all categories risk perception, stimulating public response, while functioning as a mediator for warning. The risk warning information content, channel, and type are identified as key drivers of risk perception. The research found that information channel was more related to different risk perception than other characteristics. Overall, these associations in our model explain core mechanisms behind compliance and allow policy-makers to gain new insights into preventive risk communication in public health emergencies.

This study was conducted to determine the antimicrobial resistance and virulence traits of 32 Enterococcus faecium isolates from clinical bovine mastitis cases in Ningxia Province, China. In total, 32 E. faecium isolates were taken from subclinical bovine mastitis on the basis of morphological characterization and biochemical testing, and screened for antimicrobial susceptibility. The virulence genes of the isolates were studied using polymerase chain reaction (PCR). The disc diffusion assay revealed a high occurrence of resistance against tetracycline (78.1%) and erythromycin (68.8%) in the E. faecium isolates. However, all tested E. faecium were susceptible to linezolid and vancomycin. Moreover, all E. faecium isolates harbored the erythromycin-resistant genes ermA, ermB and ermC, as well as the tetracycline-resistant genes tetK, tetL and tetM. Furthermore, all E. faecium isolates carried more than 3 of the tested virulence genes. The presence of agg (100%), cpd (100%), efaA (100%), gelE (93.4%), and esp (75.0%) was found most frequently in all the tested isolates. These findings are useful for making appropriate antimicrobial choices and developing antivirulence therapies for subclinical bovine mastitis caused by E. faecium in Ningxia Province, China., Istraživanje je provedeno kako bi se odredila antimikrobina rezistencija i svojstva virulencije izolata bakterije Enterococcus faecium uzetih u goveda s kliničkim mastitisom. U ukupno 32 izolata goveda iz pokrajine Ningxia u Kini, procijenjena je antimikrobna osjetljivost na temelju morfološke karakterizacije i biokemijskih pretraga. Geni virulencije izolata istraženi su polimeraznom lančanom reakcijom (PCR). Disk-difuzijski test je u izolatu bakterije E. faecium pokazao visoku pojavnost rezistencije na tetraciklin (78,1 %) i eritromicin (68,8 %). Svi su pretraženi izolati bili osjetljivi na linezolid i vankomicin i imali gene rezisentne na eritromicin ermA, ermB i ermC, kao i na tetraciklin, tetK, tetL i tetM. Osim toga svi izolati E. faecium nosili su više od tri istraživana gena virulencije. Najčešći geni bili agg (100 %), cpd (100 %), efaA (100 %), gelE (93,4 %) i esp (75,0 %). Ovi rezultati mogu u pokrajini Ningxia u Kini pridonijeti pravilnom izboru antimikrobnog lijeka i razvoju uspješne terapije za supklinički goveđi mastitis uzrokovan bakterijom E. faecium.

Jinli Xue,1 Mengting Zhu,2 Yanan Guo,3 Demin Kong4 1Research Center for Energy Economics, School of Business Administration, Henan Polytechnic University, Jiaozuo, People’s Republic of China; 2School of Management, Shanghai University, Shanghai, People’s Republic of China; 3School of Financial Management, Zhejiang Financial College, Hangzhou, People’s Republic of China; 4School of Humanities, Shanghai University of Finance and Economics, Shanghai, People’s Republic of ChinaCorrespondence: Mengting Zhu, School of Management, Shanghai University, Shanghai, People’s Republic of China, Tel +86-18682641363, Email jocelemy@163.comPurpose: According to the traditional view, “underdog expectations” induce self-doubt in employees, resulting in negative effects. However, a new study suggests that underdog expectations may encourage employees to work harder, resulting in positive effects. Based on regulatory focus theory, this study constructed a moderated double-mediation model to explain the “double-edged sword effect” of underdog expectations.Subjects and Methods: A three-wave survey method and leader–employee pairing method were used to conduct a questionnaire survey among 346 employees drawn from five enterprises in Shanghai, China. Statistical analysis methods, including hierarchical regression analysis, simple slope analysis, and difference analysis, were used for data analysis. SPSS 24.0, Amoss 24.0, and Mplus 7.4 software were employed to test four proposed hypotheses.Results: Under the positive moderating effect of prevention focus, underdog expectations reduce employee work engagement by adopting an avoidance path of employee feedback-avoiding behaviors(β = 0.090, p < 0.01). Moreover, underdog expectations play a negative role in this situation . Under the positive moderating effect of promotion focus, underdog expectations i

Advances in stem cell biology have posed the challenges in revealing the mechanistic themes underlying whole tissues and organs formation during regeneration. The planarian Dugesia japonica is an ideal model organism for the study of regeneration and stem cell biology. However, the genome resources for this species are still limited. Here, we combined single-molecule real-time DNA sequencing platform Pacific Biosciences (PacBio) sequencing, Illumina paired-end sequencing and 10× Genomics linked reads data to obtain the whole-genome sequence of the planarian D. japonica. The final assembled D. japonica genome is 1.13G with contig N50 of 248.44 kb, and scaffold N50 of 652.52 kb. Repeat elements account for 64.92% of the genome, and 12,031 protein coding genes were annotated, of which 10,114 genes had at least one functional annotation, representing 84.07% of the total genes. We present a highly contiguous genome assembly of D. japonica. The D. japonica genome assembly, together with gene annotation and transcriptome data provide a valuable resource to investigate molecular mechanism of planarian and stem cell research.

During infectious disease outbreaks, early warning is crucial to prevent and control the further spread of the disease. While the different waves of the Covid-19 pandemic have demonstrated the need for continued compliance, little is known about the impact of warning messages and risk perception on individual behavior in public health emergencies. To address this gap, this paper uses data from the second wave of Covid-19 in China to analyse how warning information influences preventive behavior through four categories risk perception and information interaction. Drawing on the protective action decision model (PADM) and the social amplification of risk framework (SARF), risk warning information (content, channel, and type), risk perception (threat perception, hazard- and resource-related preparedness behavior perception and stakeholder perception), information interaction, and preparedness behavior intention are integrated into a comprehensive model. To test our model, we run a survey with 724 residents in Northern China. The results show that hazard-related preparedness behavior perception and stakeholder perception act as mediators between warning and preventive action. Stakeholder perception had much stronger mediating effects than the hazard-related attributes. In addition, information interaction is effective in increasing all categories risk perception, stimulating public response, while functioning as a mediator for warning. The risk warning information content, channel, and type are identified as key drivers of risk perception. The research found that information channel was more related to different risk perception than other characteristics. Overall, these associations in our model explain core mechanisms behind compliance and allow policy-makers to gain new insights into preventive risk communication in public health emergencies., Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., Transport and Logistics, System Engineering

Advances in stem cell biology have posed the challenges in revealing the mechanistic themes underlying whole tissues and organs formation during regeneration. The planarian Dugesia japonica is an ideal model organism for the study of regeneration and stem cell biology. However, the genome resources for this species are still limited. Here, we combined single-molecule real-time DNA sequencing platform Pacific Biosciences (PacBio) sequencing, Illumina paired-end sequencing and 10× Genomics linked reads data to obtain the whole-genome sequence of the planarian D. japonica. The final assembled D. japonica genome is 1.13G with contig N50 of 248.44 kb, and scaffold N50 of 652.52 kb. Repeat elements account for 64.92% of the genome, and 12,031 protein coding genes were annotated, of which 10,114 genes had at least one functional annotation, representing 84.07% of the total genes. We present a highly contiguous genome assembly of D. japonica. The D. japonica genome assembly, together with gene annotation and transcriptome data provide a valuable resource to investigate molecular mechanism of planarian and stem cell research.

Modern x86 processors have many prefetch instructions that can be used by programmers to boost performance. However, these instructions may also cause security problems. In particular, we found that on Intel processors, there are two security flaws in the implementation of PREFETCHW, an instruction for accelerating future writes. First, this instruction can execute on data with read-only permission. Second, the execution time of this instruction leaks the current coherence state of the target data. Based on these two design issues, we build two cross-core private cache attacks that work with both inclusive and non-inclusive LLCs, named Prefetch+Reload and Prefetch+Prefetch. We demonstrate the significance of our attacks in different scenarios. First, in the covert channel case, Prefetch+Reload and Prefetch+Prefetch achieve 782 KB/s and 822 KB/s channel capacities, when using only one shared cache line between the sender and receiver, the largest-to-date single-line capacities for CPU cache covert channels. Further, in the side channel case, our attacks can monitor the access pattern of the victim on the same processor, with almost zero error rate. We show that they can be used to leak private information of real-world applications such as cryptographic keys. Finally, our attacks can be used in transient execution attacks in order to leak more secrets within the transient window than prior work. From the experimental results, our attacks allow leaking about 2 times as many secret bytes, compared to Flush+Reload, which is widely used in transient execution attacks., Comment: camera-ready for IEEE S&P 2022

In-memory computing (IMC) is an effectual solution for energy-efficient artificial intelligence applications. Analog IMC amortizes the power consumption of multiple sensing amplifiers with analog-to-digital converter (ADC), and simultaneously completes the calculation of multi-line data with high parallelism degree. Based on a universal one-transistor one-magnetic tunnel junction (MTJ) spin transfer torque magnetic RAM (STT-MRAM) cell, this paper demonstrates a novel tunneling magnetoresistance (TMR) ratio magnifying method to realize analog IMC. Previous concerns include low TMR ratio and analog calculation nonlinearity are addressed using device-circuit interaction. Peripheral circuits are minimally modified to enable in-memory matrix-vector multiplication. A current mirror with feedback structure is implemented to enhance analog computing linearity and calculation accuracy. The proposed design maximumly supports 1024 2-bit input and 1-bit weight multiply-and-accumulate (MAC) computations simultaneously. The 2-bit input is represented by the width of the input (IN) pulses, while the 1-bit weight is stored in STT-MRAM and the x7500 magnified TMR (m-TMR) ratio is obtained by latching. The proposal is simulated using 28-nm CMOS process and MTJ compact model. The integral nonlinearity is reduced by 57.6% compared with the conventional structure. 9.47-25.4 TOPS/W is realized with 2-bit input, 1-bit weight and 4-bit output convolution neural network (CNN)., Comment: 2021 submitted to IEEE Transactions on Circuits and Systems-I, regular papers

The sharing of last-level cache (LLC) among different physical cores makes cache vulnerable to side channel attacks. An attacker can get private information about co-running applications (victims) by monitoring their accesses. Cache side channel attacks can be mitigated by partitioning cache between the victim and attacker. However, previous partition works make the incorrect assumption that only the victim's cache misses are visible to attackers. In this work, we provide the key insight that both cache hits and cache misses from the victim are vulnerable. For a cache hit, although it does not affect the existence state, it can still change the replacement state and coherence state, which can also leak information to attackers. Based on this, we propose Invisible-Victim cache (IVcache), a new cache design that can mitigate both traditional LLC attacks and the new variants. IVcache classifies all processes as protected and unprotected. For accesses from protected processes, IVcache handles state changes in a slightly different way to make those accesses absolutely invisible to any other processes. We evaluate the defense effectiveness and performance of IVcache in the gem5 simulator. We show that IVcache can defend against real-world attacks, and that it introduces negligible performance effect to both protected and unprotected processes.

The sharing of last-level cache (LLC) among different physical cores makes cache vulnerable to side channel attacks. An attacker can get private information about co-running applications (victims) by monitoring their accesses. Cache side channel attacks can be mitigated by partitioning cache between the victim and attacker. However, previous partition works make the incorrect assumption that only the victim's cache misses are visible to attackers. In this work, we provide the key insight that both cache hits and cache misses from the victim are vulnerable. For a cache hit, although it does not affect the existence state, it can still change the replacement state and coherence state, which can also leak information to attackers. Based on this, we propose Invisible-Victim cache (IVcache), a new cache design that can mitigate both traditional LLC attacks and the new variants. IVcache classifies all processes as protected and unprotected. For accesses from protected processes, IVcache handles state changes in a slightly different way to make those accesses absolutely invisible to any other processes. We evaluate the defense effectiveness and performance of IVcache in the gem5 simulator. We show that IVcache can defend against real-world attacks, and that it introduces negligible performance effect to both protected and unprotected processes.

Dong Li,1,* Ying Xing,2,* Tiannv Tian,3 Yanan Guo,3 Jing Qian3,4 1Department of Thoracic Surgery, Huzhou Central Hospital, Huzhou, Zhejiang, People’s Republic of China; 2Department of Gastroenterology, The 72nd Army Hospital of the People’s Liberation Army of China, Huzhou, Zhejiang, People’s Republic of China; 3Huzhou University Schools of Nursing and Medicine, Huzhou University, Huzhou, Zhejiang, People’s Republic of China; 4Key Laboratory of Vector Biology and Pathogen Control of Zhejiang Province, Huzhou, Zhejiang, People’s Republic of China*These authors contributed equally to this workCorrespondence: Jing QianHuzhou University Schools of Nursing and Medicine, Huzhou University, Huzhou, Zhejiang Province 313000, People’s Republic of ChinaTel +8613905723707Email 02300@zjhu.edu.cnAim: LRRC59 (leucine-rich repeat-containing protein 59) is a ribosome-binding protein that also interacts with fibroblast growth factors. Limited investigations revealed a possible role of LRRC59 in the aggressive phenotype of breast cancer. However, whether LRRC59 contributes to the progression of lung cancer remains unclear.Materials and Methods: In this study, an online TCGA-based survival analysis software (GEPIA2) was used to estimate the prognostic value of LRRC59 mRNA expression level for lung cancer. Cell Counting Kit-8 assay, colony-forming assay, cell cycle analysis, and transwell assay were used to assess the biological functions of LRRC59 in lung cancer cells. Then, 94 lung adenocarcinoma (LUAD) patient tissues were collected to examine the expression level of LRRC59 by the tissue microarray (TMA)-based immunohistochemistry staining (IHC). Univariate Kaplan–Meier and multivariate Cox regression analyses were performed to evaluate the prognostic value of LRRC59 protein expression in LUAD.Results: Higher mRNA level of LRRC59 was significantly associated with worse survival for lung adenocarcinoma, but not for

One of the frontier issues that severely hamper the development of automatic snore sound classification (ASSC) associates to the lack of sufficient supervised training data. To cope with this problem, we propose a novel data augmentation approach based on semi-supervised conditional Generative Adversarial Networks (scGANs), which aims to automatically learn a mapping strategy from a random noise space to original data distribution. The proposed approach has the capability of well synthesizing 'realistic' high-dimensional data, while requiring no additional annotation process. To handle the mode collapse problem of GANs, we further introduce an ensemble strategy to enhance the diversity of the generated data. The systematic experiments conducted on a widely used Munich-Passau snore sound corpus demonstrate that the scGANs-based systems can remarkably outperform other classic data augmentation systems, and are also competitive to other recently reported systems for ASSC., Comment: accepted by IEEE JBHI

GaAs nanowires are promising candidates for advanced optoelectronic devices, despite their high surface recombination velocity and large surface-area-to-volume ratio, which renders them problematic for applications that require efficient charge collection and long charge-carrier lifetimes. Overcoating a bare GaAs nanowire core with an optimized larger-bandgap AlGaAs shell, followed by a capping layer of GaAs to prevent oxidation, has proven an effective way to passivate the nanowire surface and thereby improve electrical properties for enhanced device performance. However, it is difficult to quantify and distinguish the contributions between the nanowire core and cap layer when measuring the optoelectronic properties of a nanowire device. Here, we investigated the photoconductive terahertz (THz) response characteristics of single GaAs/AlGaAs/GaAs core–shell–cap nanowire detectors designed for THz time-domain spectroscopy. We present a detailed study of the contributions of the GaAs cap layer and GaAs core on the ultrafast optoelectronic performance of the detector. We show that both the GaAs cap and core contribute to the photoconductive signal in proportion to their relative volume in the nanowire. By increasing the cap volume ratio to above 90% of the total GaAs volume, a quasi-direct-sampling type photoconductive nanowire detector can be achieved that is highly desirable for low-noise and fast data acquisition detection.

Everolimus, an inhibitor of the mammalian target of rapamycin (mTOR), is effective in treating tumors harboring alterations in the mTOR pathway. Mechanisms of resistance to everolimus remain undefined. Resistance developed in a patient with metastatic anaplastic thyroid carcinoma after an extraordinary 18-month response. Whole-exome sequencing of pretreatment and drug-resistant tumors revealed a nonsense mutation in TSC2, a negative regulator of mTOR, suggesting a mechanism for exquisite sensitivity to everolimus. The resistant tumor also harbored a mutation in MTOR that confers resistance to allosteric mTOR inhibition. The mutation remains sensitive to mTOR kinase inhibitors.

The prevalence of hyperuricemia and gout has been increasing, but the comparative effectiveness and safety of different treatments remain uncertain. We aimed to compare the effectiveness and safety of different treatments for hyperuricemia using network meta-analysis methodology. We systematically reviewed fifteen randomized controlled trials (involving 7,246 patients through January 2016) that compared the effects of different urate-lowering drugs (allopurinol, benzbromarone, febuxostat, pegloticase and probenecid) on hyperuricemia. Drug efficacy and safety, as outcomes, were measured by whether the target level of serum urate acid was achieved and whether any adverse events occurred, respectively. We derived pooled effect sizes expressed as odds ratios (ORs) and 95% confidence intervals (CIs). The efficacy and safety of the drugs were ranked by cumulative ranking probabilities. Our findings show that febuxostat, benzbromarone, probenecid, pegloticase, and allopurinol were all highly effective at reducing the risk of hyperuricemia compared to placebo. Febuxostat had the best efficacy and safety compared to the other drugs. Furthermore, febuxostat 120 mg QD was more effective at achieving urate-lowering targets (OR: 0.17, 95% CI: 0.12-0.24) and safer (OR: 0.72, 95% CI: 0.56-0.91) than allopurinol.

CfAvr4, a chitin-binding effector protein produced by the Dothideomycete tomato pathogen Cladosporium fulvum, protects the cell wall of this fungus against hydrolysis by secreted host chitinases during infection. However, in the presence of the Cf-4 immune receptor of tomato, CfAvr4 triggers a hypersensitive response (HR), which renders the pathogen avirulent. Recently, several orthologues of CfAvr4 have been identified from phylogenetically closely related species of Dothideomycete fungi. Of these, DsAvr4 from Dothistroma septosporum also triggers a Cf-4-dependent HR, but CaAvr4 and CbAvr4 from Cercospora apii and Cercospora beticola, respectively, do not. All, however, bind chitin. To identify the region(s) and specific amino acid residue(s) of CfAvr4 and DsAvr4 required to trigger a Cf-4-dependent HR, chimeric and mutant proteins, in which specific protein regions or single amino acid residues, respectively, were exchanged between CfAvr4 and CaAvr4 or DsAvr4 and CbAvr4, were tested for their ability to trigger an HR in Nicotiana benthamiana plants transgenic for the Cf-4 immune receptor gene. Based on this approach, a single region common to CfAvr4 and DsAvr4 was determined to carry a conserved proline residue necessary for the elicitation of this HR. In support of this result, a Cf-4-dependent HR was triggered by mutant CaAvr4 and CbAvr4 proteins carrying an arginine-to-proline substitution at this position. This study provides the first step in deciphering how Avr4 orthologues from different Dothideomycete fungi trigger a Cf-4-dependent HR.

CfAvr4, a chitin-binding effector protein produced by the Dothideomycete tomato pathogen Cladosporium fulvum, protects the cell wall of this fungus against hydrolysis by secreted host chitinases during infection. However, in the presence of the Cf-4 immune receptor of tomato, CfAvr4 triggers a hypersensitive response (HR), which renders the pathogen avirulent. Recently, several orthologues of CfAvr4 have been identified from phylogenetically closely related species of Dothideomycete fungi. Of these, DsAvr4 from Dothistroma septosporum also triggers a Cf-4-dependent HR, but CaAvr4 and CbAvr4 from Cercospora apii and Cercospora beticola, respectively, do not. All, however, bind chitin. To identify the region(s) and specific amino acid residue(s) of CfAvr4 and DsAvr4 required to trigger a Cf-4-dependent HR, chimeric and mutant proteins, in which specific protein regions or single amino acid residues, respectively, were exchanged between CfAvr4 and CaAvr4 or DsAvr4 and CbAvr4, were tested for their ability to trigger an HR in Nicotiana benthamiana plants transgenic for the Cf-4 immune receptor gene. Based on this approach, a single region common to CfAvr4 and DsAvr4 was determined to carry a conserved proline residue necessary for the elicitation of this HR. In support of this result, a Cf-4-dependent HR was triggered by mutant CaAvr4 and CbAvr4 proteins carrying an arginine-to-proline substitution at this position. This study provides the first step in deciphering how Avr4 orthologues from different Dothideomycete fungi trigger a Cf-4-dependent HR.

CfAvr4, a chitin-binding effector protein produced by the Dothideomycete tomato pathogen Cladosporium fulvum, protects the cell wall of this fungus against hydrolysis by secreted host chitinases during infection. However, in the presence of the Cf-4 immune receptor of tomato, CfAvr4 triggers a hypersensitive response (HR), which renders the pathogen avirulent. Recently, several orthologues of CfAvr4 have been identified from phylogenetically closely related species of Dothideomycete fungi. Of these, DsAvr4 from Dothistroma septosporum also triggers a Cf-4-dependent HR, but CaAvr4 and CbAvr4 from Cercospora apii and Cercospora beticola, respectively, do not. All, however, bind chitin. To identify the region(s) and specific amino acid residue(s) of CfAvr4 and DsAvr4 required to trigger a Cf-4-dependent HR, chimeric and mutant proteins, in which specific protein regions or single amino acid residues, respectively, were exchanged between CfAvr4 and CaAvr4 or DsAvr4 and CbAvr4, were tested for their ability to trigger an HR in Nicotiana benthamiana plants transgenic for the Cf-4 immune receptor gene. Based on this approach, a single region common to CfAvr4 and DsAvr4 was determined to carry a conserved proline residue necessary for the elicitation of this HR. In support of this result, a Cf-4-dependent HR was triggered by mutant CaAvr4 and CbAvr4 proteins carrying an arginine-to-proline substitution at this position. This study provides the first step in deciphering how Avr4 orthologues from different Dothideomycete fungi trigger a Cf-4-dependent HR.

CfAvr4, a chitin-binding effector protein produced by the Dothideomycete tomato pathogen Cladosporium fulvum, protects the cell wall of this fungus against hydrolysis by secreted host chitinases during infection. However, in the presence of the Cf-4 immune receptor of tomato, CfAvr4 triggers a hypersensitive response (HR), which renders the pathogen avirulent. Recently, several orthologues of CfAvr4 have been identified from phylogenetically closely related species of Dothideomycete fungi. Of these, DsAvr4 from Dothistroma septosporum also triggers a Cf-4-dependent HR, but CaAvr4 and CbAvr4 from Cercospora apii and Cercospora beticola, respectively, do not. All, however, bind chitin. To identify the region(s) and specific amino acid residue(s) of CfAvr4 and DsAvr4 required to trigger a Cf-4-dependent HR, chimeric and mutant proteins, in which specific protein regions or single amino acid residues, respectively, were exchanged between CfAvr4 and CaAvr4 or DsAvr4 and CbAvr4, were tested for their ability to trigger an HR in Nicotiana benthamiana plants transgenic for the Cf-4 immune receptor gene. Based on this approach, a single region common to CfAvr4 and DsAvr4 was determined to carry a conserved proline residue necessary for the elicitation of this HR. In support of this result, a Cf-4-dependent HR was triggered by mutant CaAvr4 and CbAvr4 proteins carrying an arginine-to-proline substitution at this position. This study provides the first step in deciphering how Avr4 orthologues from different Dothideomycete fungi trigger a Cf-4-dependent HR.

The ever-growing popularity of Kinect and inertial sensors has prompted intensive research efforts on human action recognition. Since human actions can be characterized by multiple feature representations extracted from Kinect and inertial sensors, multiview features must be encoded into a unified space optimal for human action recognition. In this paper, we propose a new unsupervised feature fusion method termed Multiview Cauchy Estimator Feature Embedding (MCEFE) for human action recognition. By minimizing empirical risk, MCEFE integrates the encoded complementary information in multiple views to find the unified data representation and the projection matrices. To enhance robustness to outliers, the Cauchy estimator is imposed on the reconstruction error. Furthermore, ensemble manifold regularization is enforced on the projection matrices to encode the correlations between different views and avoid overfitting. Experiments are conducted on the new Chinese Academy of Sciences - Yunnan University - Multimodal Human Action Database (CAS-YNU-MHAD) to demonstrate the effectiveness and robustness of MCEFE for human action recognition., Comment: This paper has been withdrawn by the author due to a crucial error

The development of earth abundant materials for optoelectronics and photovoltaics promises improvements in sustainability and scalability. Recent studies have further demonstrated enhanced material efficiency through the superior light management of novel nanoscale geometries such as the nanowire. Here we show that an industry standard epitaxy technique can be used to fabricate high quality II-V nanowires (1D) and nanoplatelets (2D) of the earth abundant semiconductor Zn3As2. We go on to establish the optoelectronic potential of this material by demonstrating efficient photoemission and detection at 1.0 eV, an energy which is significant to the fields of both photovoltaics and optical telecommunications. Through dynamical spectroscopy this superior performance is found to arise from a low rate of surface recombination combined with a high rate of radiative recombination. These results introduce nanostructured Zn3As2 as a high quality optoelectronic material ready for device exploration.

Photoconductive terahertz detectors based on single GaAs/AlGaAs nanowire were designed, fabricated and incorporated into the pulsed time-domain technique, showing a promise for nanowires in terahertz applications such as near-field terahertz sensors or on-chip terahertz micro-spectrometers.

We report an analysis method that combines microphotoluminescence mapping and lifetime mapping data of single semiconductor nanowires to extract the doping concentration, nonradiative lifetime, and internal quantum efficiency along the length of the nanowires. Using this method, the doping concentration of single Si-doped wurtzite InP nanowires are mapped out and confirmed by the electrical measurements of single nanowire devices. Our method has important implication for single nanowire detectors and LEDs and nanowire solar cells applications.

Dothistroma septosporum is the main causal agent of Dothistroma needle blight of pines. However little is known about mechanisms of pine resistance against D. septosporum, or whether there is any classical gene-for-gene resistance involved. The molecular basis of how fungal effector proteins can trigger plant host resistance in a gene-for-gene manner was determined partly by work with the model fungus Cladosporium fulvum and its tomato host. Comparative genome analysis of C. fulvum and D. septosporum genomes identified nine putative effector genes (DsAvr4, DsEcp2-1, DsEcp2-2, DsEcp2-3, DsEcp4, DsEcp5, DsEcp6, DsEcp13 and DsEcp14) in D. septosporum that are homologous to well-characterized C. fulvum effector genes. Other effector candidates were identified as small cysteine rich proteins that are highly expressed in planta, including DsHdp1 which is a hydrophobin gene and Ds69335 which belongs to the sperm-coating protein-like extracellular protein SCP/Tpx-1/Ag5/PR-1/Sc7 (SCP/TAPS) superfamily. Transcriptome analysis showed that, except for DsEcp2-1 and DsEcp6, the in planta expression of D. septosporum effectors was low. Targeted gene replacement of DsAvr4, DsEcp2-1, DsEcp6 and DsHdp1 caused no observed changes in fungal physiology in vitro compared to wild type (WT) and also showed that DsAvr4, DsEcp6 and DsHdp1 are not virulence factors when infecting Pinus radiata. However deletion of DsEcp2-1 caused larger lesions compared to WT, suggesting that DsEcp2-1 may act to suppress a host target which is involved in necrosis induction during the biotrophic infection stage. A domain swap experiment in this study showed that swapping the region between cysteine residues C6 (Cys102) to C7 (Cys114), which contains the chitin binding domain, caused loss of resistance (R) protein Cf-4 recognition of DsAvr4 (with CbAvr4) and gain of Cf-4 recognition of CbAv4 (with DsAvr4 or CfAvr4). Further experiments carried out in Wageningen University showed that a Pro residue located in t

We demonstrate how growth parameters may be adopted to produce morphologically controlled high-quality indium phosphide (InP) nanowires suitable for optoelectronic device applications. Growth temperature, V/III ratio, and catalyst particle size have a significant effect on the morphology, crystallographic quality, and optical properties of the resulting nanowires. Significantly, we find that higher growth temperatures or higher V/III ratios promote the formation of wurtzite (WZ) nanowires while zinc-blende (ZB) nanowires are favourable at lower growth temperatures and lower V/III ratios. Results also show that InP nanowires grow preferably in the WZ crystal structure than the ZB crystal structure with increasing V/III ratio or decreasing diameter. This causes a blue-shift in the bandgap as growth temperature increases. These results show that careful control of growth temperature, V/III ratio and catalyst size are crucial for obtaining InP nanowires of a specific crystal structure needed for device applications.

Photoconductive terahertz detectors based on single GaAs/AlGaAs core-shell nanowire have been designed and fabricated. The devices were characterised in a terahertz time-domain spectroscopy system, showing excellent sensitivity comparable to the standard

We demonstrate how growth parameters may be adopted to produce morphologically controlled high-quality indium phosphide (InP) nanowires suitable for optoelectronic device applications. Growth temperature, V/III ratio, and catalyst particle size have a significant effect on the morphology, crystallographic quality, and optical properties of the resulting nanowires. Significantly, we find that higher growth temperatures or higher V/III ratios promote the formation of wurtzite (WZ) nanowires while zinc-blende (ZB) nanowires are favourable at lower growth temperatures and lower V/III ratios. Results also show that InP nanowires grow preferably in the WZ crystal structure than the ZB crystal structure with increasing V/III ratio or decreasing diameter. This causes a blue-shift in the bandgap as growth temperature increases. These results show that careful control of growth temperature, V/III ratio and catalyst size are crucial for obtaining InP nanowires of a specific crystal structure needed for device applications.

We demonstrate how growth parameters may be adopted to produce morphologically controlled high-quality indium phosphide (InP) nanowires suitable for optoelectronic device applications. Growth temperature, V/III ratio, and catalyst particle size have a significant effect on the morphology, crystallographic quality, and optical properties of the resulting nanowires. Significantly, we find that higher growth temperatures or higher V/III ratios promote the formation of wurtzite (WZ) nanowires while zinc-blende (ZB) nanowires are favourable at lower growth temperatures and lower V/III ratios. Results also show that InP nanowires grow preferably in the WZ crystal structure than the ZB crystal structure with increasing V/III ratio or decreasing diameter. This causes a blue-shift in the bandgap as growth temperature increases. These results show that careful control of growth temperature, V/III ratio and catalyst size are crucial for obtaining InP nanowires of a specific crystal structure needed for device applications.

Simultaneous growth of <111> free-standing and 6[110] lateral GaAsP epitaxial nanowires on GaAs (001) substrates were observed and investigated by electron microscopy and crystallographic analysis. It was found that the growth of both free-standing and lateral ternary nanowires via Au catalysts was driven by the fact that Au catalysts prefer to maintain low-energy {111}B interfaces with surrounding GaAs(P) materials: in the case of free-standing nanowires, Au catalysts maintain {111}B interfaces with their underlying GaAsP nanowires; while in the case of lateral nanowires, each Au catalyst remain their side {111}B interfaces with the surrounding GaAs(P) material during the lateral nanowire growth

Manipulating the composition and morphology of semiconductor nanowires in a precisely controlled fashion is critical in developing nanowire devices. This is particularly true for ternary III-V nanowires. Many studies have shown the complexities within tho

In this study, the behavior of P incorporation GaAsP during ternary nanowires epitaxial growth is investigated. Detailed electron microscopy investigations indicate that (1) the P concentration in the nanowires is higher than that in the simultaneously gr

We report a novel phase separation phenomenon observed in the growth of ternary InxGa1-xAs nanowires by metalorganic chemical vapor deposition. A spontaneous formation of core-shell nanowires is investigated by cross-sectional transmission electron microscopy, revealing the compositional complexity within the ternary nanowires. It has been found that for InxGa1-xAs nanowires high precursor flow rates generate ternary InxGa1-xAs cores with In-rich shells, while low precursor flow rates produce binary GaAs cores with ternary In xGa1-xAs shells. First-principle calculations combined with thermodynamic considerations suggest that this phenomenon is due to competitive alloying of different group-III elements with Au catalysts, and variations in elemental concentrations of group-III materials in the catalyst under different precursor flow rates. This study shows that precursor flow rates are critical factors for manipulating Au catalysts to produce nanowires of desired composition.

We sequenced and compared the genomes of the Dothideomycete fungal plant pathogens Cladosporium fulvum (Cfu) (syn. Passalora fulva) and Dothistroma septosporum (Dse) that are closely related phylogenetically, but have different lifestyles and hosts. Although both fungi grow extracellularly in close contact with host mesophyll cells, Cfu is a biotroph infecting tomato, while Dse is a hemibiotroph infecting pine. The genomes of these fungi have a similar set of genes (70percent of gene content in both genomes are homologs), but differ significantly in size (Cfu >61.1-Mb; Dse 31.2-Mb), which is mainly due to the difference in repeat content (47.2percent in Cfu versus 3.2percent in Dse). Recent adaptation to different lifestyles and hosts is suggested by diverged sets of genes. Cfu contains an tomatinase gene that we predict might be required for detoxification of tomatine, while this gene is absent in Dse. Many genes encoding secreted proteins are unique to each species and the repeat-rich areas in Cfu are enriched for these species-specific genes. In contrast, conserved genes suggest common host ancestry. Homologs of Cfu effector genes, including Ecp2 and Avr4, are present in Dse and induce a Cf-Ecp2- and Cf-4-mediated hypersensitive response, respectively. Strikingly, genes involved in production of the toxin dothistromin, a likely virulence factor for Dse, are conserved in Cfu, but their expression differs markedly with essentially no expression by Cfu in planta. Likewise, Cfu has a carbohydrate-degrading enzyme catalog that is more similar to that of necrotrophs or hemibiotrophs and a larger pectinolytic gene arsenal than Dse, but many of these genes are not expressed in planta or are pseudogenized. Overall, comparison of their genomes suggests that these closely related plant pathogens had a common ancestral host but since adapted to different hosts and lifestyles by a combination of differentiated gene content, pseudogenization, and gene regulation.

Thesis (Ph.D.)--University of Rochester. School of Medicine and Dentistry. Dept. of Interdepartmental Graduate Program in Neuroscience, 2008., BIM is a proapoptotic member of the Bcl-2 family. Within this family, BIM is part of a subfamily known as BH3-only. BH3-only proteins including BIM promote cell death by either sequestering the anti-apoptotic members Bcl-2 or Bcl-xL or by direct binding with the proapoptotic protein Bax or Bak to facilitate their activation. Understanding how BH3-only proteins act to promote cell death and how they are regulated in response to cell death and survival signals are important goals for researchers investigating cell death mechanisms. The overall aim of this thesis is to characterize two novel protein interactions involving BIMEL—one with the product of the von Hippel-Lindau (VHL) gene pVHL, and the other one with the HIF prolyl hydroxylase EGLN3. Germ-line mutation of the VHL tumor-suppressor gene results in a dominantly inherited cancer syndrome characterized by the development of hemangioblastomas, pheochromocytomas and renal clear-cell carcinoma (RCC). RCC cells expressing wild type pVHL are more sensitive to the chemotherapeutic agent etoposide and UV radiation-induced cell death than RCC cells lacking pVHL. Recently, reduced expression of the proapoptotic protein BIMEL was correlated with resistance of RCC cells to these same apoptotic stimuli. Based on our finding that BIMEL can co-immunoprecipitate with pVHL, we wondered if the status of pVHL might affect BIMEL protein levels. RCC cells with wild type pVHL have a higher basal level of BIMEL protein. The presence or absence of pVHL did not affect BIMEL mRNA levels but did influence BIMEL protein stability. Consistent with these results, BIMEL protein half life was prolonged in cells expressing pVHL, and overexpression of pVHL reduced BIMEL polyubiquitination and degradation induced by ERK1/2 activation. Knocking down pVHL expression by RNA interference decreased BIMEL protein levels and decreased the sensitivity of RCC cells to apoptotic stimuli. Directly knocking down BIMEL by siRNA decreased the sensitivity of R

Yanan Guo1, Dechun Zhang1, He Lu1, Shuang Luo2, Xuecheng Shen31Molecular Medicine and Tumor Research Center, Chongqing Medical University, Yuzhong District, 2Department of Obstetrics and Gynecology, First Affiliated Hospital of Chongqing Medical University, 3Urological Research Institute of PLA, Southwest Hospital, Third Military Medical University, Chongqing, People's Republic of ChinaBackground: The purpose of this study was to examine the possible contribution of calcifying nanoparticles to the pathogenesis of placental calcification.Methods: Calcified placental tissues and distal tissue samples were collected from 36 confirmed placental calcification cases. In addition, 20 normal placental tissue samples were obtained as a control group. All the tissue samples were cultured using special nanobacterial culture methods. The cultured calcifying nanoparticles were examined by transmission electron microscopy (TEM), and their growth was monitored by optical density (OD) at a wavelength of 650 nm. 16S rRNA gene expression of the cultured calcifying nanoparticles was also isolated and sequenced.Results: Novel calcifying nanoparticles wrapped with electron-dense shells between 50 nm to 500 nm in diameter were observed in the extracellular matrix of calcified placental tissues. They were detected in placental villi and hydroxyapatite crystals, and contained “nucleic acid-like materials”. After isolation and four weeks of culture, 28 of 36 calcified placental tissue samples showed white granular precipitates attached to the bottom of the culture tubes. OD650 measurements indicated that the precipitates from the calcified placental tissues were able to grow in culture, whereas no such precipitates from the control tissues were observed. The 16S rRNA genes were isolated from the cultured calcifying nanoparticles and calcified placental tissues, and their gene sequencing results implied that calcifying nanoparticles were novel nanobacteria (GenBan

We sequenced and compared the genomes of the Dothideomycete fungal plant pathogens Cladosporium fulvum (Cfu) (syn. Passalora fulva) and Dothistroma septosporum (Dse) that are closely related phylogenetically, but have different lifestyles and hosts. Although both fungi grow extracellularly in close contact with host mesophyll cells, Cfu is a biotroph infecting tomato, while Dse is a hemibiotroph infecting pine. The genomes of these fungi have a similar set of genes (70percent of gene content in both genomes are homologs), but differ significantly in size (Cfu >61.1-Mb; Dse 31.2-Mb), which is mainly due to the difference in repeat content (47.2percent in Cfu versus 3.2percent in Dse). Recent adaptation to different lifestyles and hosts is suggested by diverged sets of genes. Cfu contains an tomatinase gene that we predict might be required for detoxification of tomatine, while this gene is absent in Dse. Many genes encoding secreted proteins are unique to each species and the repeat-rich areas in Cfu are enriched for these species-specific genes. In contrast, conserved genes suggest common host ancestry. Homologs of Cfu effector genes, including Ecp2 and Avr4, are present in Dse and induce a Cf-Ecp2- and Cf-4-mediated hypersensitive response, respectively. Strikingly, genes involved in production of the toxin dothistromin, a likely virulence factor for Dse, are conserved in Cfu, but their expression differs markedly with essentially no expression by Cfu in planta. Likewise, Cfu has a carbohydrate-degrading enzyme catalog that is more similar to that of necrotrophs or hemibiotrophs and a larger pectinolytic gene arsenal than Dse, but many of these genes are not expressed in planta or are pseudogenized. Overall, comparison of their genomes suggests that these closely related plant pathogens had a common ancestral host but since adapted to different hosts and lifestyles by a combination of differentiated gene content, pseudogenization, and gene regulation.

In this study, we demonstrated that by using annealed Au thin films as catalysts, high-density, defect-free, and taper-restrained epitaxial GaAs nanowires were grown on GaAs (111)B substrates. The as-grown nanowires were compared with low-density Au colloidal nanoparticle catalyzed GaAs nanowires grown under identical conditions in the same metal-organic chemical vapor deposition reactor. Through detailed morphological and structural characterizations using advanced electron microscopy, we discovered that GaAs epitaxial nanowire tapering can be efficiently restrained by increasing the density of Au catalysts. By increasing the density of the Au catalysts, the axial growth rate of nanowires is reduced, which, in turn, limits the formation of lattice defects. Furthermore, the comprehensive investigation of GaAs nanowires catalyzed by Au thin film of different thicknesses (1 nm, 2 nm, 3 nm, and 5 nm) and Au colloidal particles of different densities indicates that the density of the Au catalysts play an important role in GaAs nanowire growth. This comprehensive study provides an opportunity to explore the effects of the catalysts and the growth mechanisms of III-V epitaxial semiconductor nanowires.