78 research outputs found
ZnCdS Dotted with Highly Dispersed Pt Supported on SiO2 Nanospheres Promoting Photocatalytic Hydrogen Evolution
[EN] The efficiency of solar hydrogen evolution closely depends on the fast transfer of charge carriers and the effective use of visible light. In this work, a novel photocatalyst SiO2/ZnCdS/Pt was successfully prepared to solve these two problems. An artistic structure of the photocatalyst was constructed and ZnCdS was successfully wrapped on the surface of SiO2 spheres with uniform Pt nanoparticles (NPs) in a size of 4.1 +/- 0.7 nm highly dispersed on the ZnCdS shell through the self-assembly method. Pt NPs can absorb the scattered light in the near field of SiO2 spheres. With the synergistic effect of SiO2 spheres and small highly dispersed Pt NPs, the absorption of visible light was significantly promoted. Meanwhile, the electron-hole recombination was also effectively inhibited, thus improving the photocatalytic activity. The hydrogen production activity of the highly efficient photocatalyst was as high as 8.3 mmol g(-1) h(-1) under visible light (lambda > 420 nm). The photocatalytic activity of SiO2/ZnCdS/Pt was 2.9 times higher than that of the ZnCdS/Pt photocatalyst.This work was supported by the National Natural Science Foundation of China (21976111), Shandong Provincial Natural Science Foundation (ZR2019MB052), and Large Instrument Open Foundation of Shandong Normal University (KFJJ2019004; KFJJ2021006).Liu, K.; Peng, L.; Zhen, P.; Chen, L.; Song, S.; García Gómez, H.; Sun, C. (2021). ZnCdS Dotted with Highly Dispersed Pt Supported on SiO2 Nanospheres Promoting Photocatalytic Hydrogen Evolution. The Journal of Physical Chemistry C. 125(27):14656-14665. https://doi.org/10.1021/acs.jpcc.1c0353514656146651252
Solving Challenging Math Word Problems Using GPT-4 Code Interpreter with Code-based Self-Verification
Recent progress in large language models (LLMs) like GPT-4 and PaLM-2 has
brought significant advancements in addressing math reasoning problems. In
particular, OpenAI's latest version of GPT-4, known as GPT-4 Code Interpreter,
shows remarkable performance on challenging math datasets. In this paper, we
explore the effect of code on enhancing LLMs' reasoning capability by
introducing different constraints on the \textit{Code Usage Frequency} of GPT-4
Code Interpreter. We found that its success can be largely attributed to its
powerful skills in generating and executing code, evaluating the output of code
execution, and rectifying its solution when receiving unreasonable outputs.
Based on this insight, we propose a novel and effective prompting method,
explicit \uline{c}ode-based \uline{s}elf-\uline{v}erification~(CSV), to further
boost the mathematical reasoning potential of GPT-4 Code Interpreter. This
method employs a zero-shot prompt on GPT-4 Code Interpreter to encourage it to
use code to self-verify its answers. In instances where the verification state
registers as ``False'', the model shall automatically amend its solution,
analogous to our approach of rectifying errors during a mathematics
examination. Furthermore, we recognize that the states of the verification
result indicate the confidence of a solution, which can improve the
effectiveness of majority voting. With GPT-4 Code Interpreter and CSV, we
achieve an impressive zero-shot accuracy on MATH dataset \textbf{(53.9\%
84.3\%)}.Comment: Solving Challenging Math Word Problems Using GPT-4 Code Interpreter
with Code-based Self-Verificatio
DeVLBert: Learning Deconfounded Visio-Linguistic Representations
In this paper, we propose to investigate the problem of out-of-domain
visio-linguistic pretraining, where the pretraining data distribution differs
from that of downstream data on which the pretrained model will be fine-tuned.
Existing methods for this problem are purely likelihood-based, leading to the
spurious correlations and hurt the generalization ability when transferred to
out-of-domain downstream tasks. By spurious correlation, we mean that the
conditional probability of one token (object or word) given another one can be
high (due to the dataset biases) without robust (causal) relationships between
them. To mitigate such dataset biases, we propose a Deconfounded
Visio-Linguistic Bert framework, abbreviated as DeVLBert, to perform
intervention-based learning. We borrow the idea of the backdoor adjustment from
the research field of causality and propose several neural-network based
architectures for Bert-style out-of-domain pretraining. The quantitative
results on three downstream tasks, Image Retrieval (IR), Zero-shot IR, and
Visual Question Answering, show the effectiveness of DeVLBert by boosting
generalization ability.Comment: 10 pages, 4 figures, to appear in ACM MM 2020 proceeding
Genomic Insights into the Formation of Human Populations in East Asia
厦门大学人类学研究所、厦门大学生命科学学院细胞应激生物学国家重点实验室王传超教授课题组与哈佛医学院David Reich教授团队合作,联合全球43个单位的85位共同作者组成的国际合作团队通过古DNA精细解析东亚人群形成历史。研究人员利用古DNA数据检验了东亚地区农业和语言共扩散理论,综合考古学、语言学等证据,该研究系统性地重构了东亚人群的形成、迁徙和混合历史。这是目前国内开展的东亚地区最大规模的考古基因组学研究,此次所报道的东亚地区古人基因组样本量是以往国内研究机构所发表的样本量总和的两倍,改变了东亚地区尤其是中国境内考古基因组学研究长期滞后的局面。
该研究是由王传超教授团队与哈佛医学院(David Reich教授)、德国马普人类历史科学研究所(Johannes Krause教授)、复旦大学现代人类学教育部重点实验室(李辉教授和金力院士)、维也纳大学进化人类学系(Ron Pinhasi副教授)、南洋理工大学人文学院(Hui-Yuan Yeh助理教授)、俄罗斯远东联邦大学科学博物馆(Alexander N Popov研究员)、西安交通大学(张虎勤教授)、蒙古国国家博物馆研究中心、乌兰巴托国立大学考古系、华盛顿大学人类学系、台湾成功大学考古所、加州大学人类学系等全球43个单位的85位共同作者组成的国际合作团队联合完成的。厦门大学人类学研究所、厦门大学生命科学学院细胞应激生物学国家重点实验室为论文第一完成单位。厦门大学人类学研究所韦兰海副教授、胡荣助理教授、郭健新博士后、何光林博士后和杨晓敏硕士参与了研究工作。The deep population history of East Asia remains poorly understood due to a lack of ancient DNA data and sparse sampling of present-day people1,2. We report genome-wide data from 166 East Asians dating to 6000 BCE-1000 CE and 46 present-day groups. Hunter-gatherers from Japan, the Amur River Basin, and people of Neolithic and Iron Age Taiwan and the Tibetan plateau are linked by a deeply-splitting lineage likely reflecting a Late Pleistocene coastal migration. We follow Holocene expansions from four regions. First, hunter-gatherers of Mongolia and the Amur River Basin have ancestry shared by Mongolic and Tungusic language speakers but do not carry West Liao River farmer ancestry contradicting theories that their expansion spread these proto-languages. Second, Yellow River Basin farmers at ~3000 BCE likely spread Sino-Tibetan languages as their ancestry dispersed both to Tibet where it forms up ~84% to some groups and to the Central Plain where it contributed ~59-84% to Han Chinese. Third, people from Taiwan ~1300 BCE to 800 CE derived ~75% ancestry from a lineage also common in modern Austronesian, Tai-Kadai and Austroasiatic speakers likely deriving from Yangtze River Valley farmers; ancient Taiwan people also derived ~25% ancestry from a northern lineage related to but different from Yellow River farmers implying an additional north-to-south expansion. Fourth, Yamnaya Steppe pastoralist ancestry arrived in western Mongolia after ~3000 BCE but was displaced by previously established lineages even while it persisted in western China as expected if it spread the ancestor of Tocharian Indo-European languages. Two later gene flows affected western Mongolia: after ~2000 BCE migrants with Yamnaya and European farmer ancestry, and episodic impacts of later groups with ancestry from Turan.We thank David Anthony, Ofer Bar-Yosef, Katherine Brunson, Rowan Flad, Pavel Flegontov,Qiaomei Fu, Wolfgang Haak, Iosif Lazaridis, Mark Lipson, Iain Mathieson, Richard Meadow,Inigo Olalde, Nick Patterson, Pontus Skoglund, Dan Xu, and the four reviewers for valuable comments. We thank Naruya Saitou and the Asian DNA Repository Consortium for sharing genotype data from present-day Japanese groups. We thank Toyohiro Nishimoto and Takashi Fujisawa from the Rebun Town Board of Education for sharing the Funadomari Jomon samples, and Hideyo Tanaka and Watru Nagahara from the Archeological Center of Chiba City who are excavators of the Rokutsu Jomon site. The excavations at Boisman-2 site (Boisman culture), the Pospelovo-1 site (Yankovsky culture), and the Roshino-4 site (Heishui Mohe culture) were funded by the Far Eastern Federal University and the Institute of History,Archaeology and Ethnology Far Eastern Branch of the Russian Academy of Sciences; research on Pospelovo-1 is funded by RFBR project number 18-09-40101. C.C.W was funded by the Max Planck Society, the National Natural Science Foundation of China (NSFC 31801040), the Nanqiang Outstanding Young Talents Program of Xiamen University (X2123302), the Major project of National Social Science Foundation of China (20&ZD248), a European Research Council (ERC) grant to Dan Xu (ERC-2019-ADG-883700-TRAM) and Fundamental Research Funds for the Central Universities (ZK1144). O.B. and Y.B. were funded by Russian Scientific Foundation grant 17-14-01345. H.M. was supported by the grant JSPS 16H02527. M.R. and C.C.W received funding from the ERC under the European Union’s Horizon 2020 research and innovation program (grant No 646612) to M.R. The research of C.S. is supported 30 by the Calleva Foundation and the Human Origins Research Fund. H.L was funded NSFC (91731303, 31671297), B&R International Joint Laboratory of Eurasian Anthropology (18490750300). J.K. was funded by DFG grant KR 4015/1-1, the Baden Württemberg Foundation, and the Max Planck Institute. Accelerator Mass Spectrometry radiocarbon dating work was supported by the National Science Foundation (NSF) (BCS-1460369) to D.J.K. and B.J.C. D.R. was funded by NSF grant BCS-1032255, NIH (NIGMS) grant GM100233, the Paul M. Allen Frontiers Group, John Templeton Foundation grant 61220, a gift from Jean-Francois Clin, and the Howard Hughes Medical Institute.
该研究得到了国家自然科学基金“中国东南各族群的遗传混合”、国家社科基金重大项目“多学科视角下的南岛语族的起源和形成研究”、厦门大学南强青年拔尖人才支持计划A类、中央高校基本科研业务费等资助
Preparation and Application of Foaming Agent Based on the Compound System of Short-Chain Fluorocarbon and Soybean Residue Protein
This study provides a new idea for the design of an advanced foaming agent with soybean residue protein (SRP) as a potential protein source. In order to achieve the most effective foaming performance, we employed the novel approach of response surface methodology (RSM) to improve important process parameters in a hot-alkali experiment. The experimental results showed that the optimum reaction parameters of pH and temperature were pH 10.2 and 50.5 °C, respectively, which, when continued for 3 h, led to the highest foaming property of the SRP foaming agent (486 mL). Based on the scheme, we also designed an experiment whereby we incorporated 1.0g/L FS-50 into the SRP foaming agent (SRP-50) to achieve higher foaming capacity compared with the commercial foaming agent. This foaming agent was cheaper than commercial vegetable protein foaming agents (12 USD/L) at 0.258 USD/L. Meanwhile, the properties of foam concrete prepared using SRP-50 were studied in comparison with a commercial vegetable protein foaming agent (PS). The results demonstrated that the foam prepared using SRP-50 had better stability, and the displacement of the foam decreased by 10% after 10 min. During the curing period, the foam concrete possesseda compressive strength of 5.72 MPa after 28 days, which was an increase from 2.95 MPa before. The aperture of the foam ranged from 100 to 500 μm with the percentage increasing up to 71.5%, which indicated narrower pore-size distribution and finer pore size. In addition, the shrinkage of the foam concrete was also improved. These findings not only achieve the utilization of waste but also provide a new source for protein foaming agents
Efficacy of Two Tank-Mix Adjuvants to Control Mango Thrips Using a UAV Sprayer
Thrips have become some of the most challenging pests to control in mango production due to their short developmental time, hidden locations and resistance to pesticides, in the tropical regions of China. To improve pesticides efficacy, the tank-mix adjuvants Qi Gong (QG) and the thrips attractant Lv Dian (LD) were added when using an unmanned aerial vehicle (UAV) to control thrips. The surface tension, contact angle on mango leaves, droplet size, spreading rate, and drying time of the two tank-mix adjuvants were determined. The effects of the two tank-mix adjuvants using a UAV sprayer on the droplet coverage and control efficacy against thrips on mango inflorescences were tested through field trials. The results showed that both QG and LD could reduce the surface tension of the liquid and the contact angle on mango leaves and could increase the spreading performance. The droplet coverage in the upper layer of the canopy was about 2% higher than that in the lower layer, and the coverage at the top of the panicle was 5% higher than that at the bottom. QG improved the deposition coverage of mango inflorescences by about 31.5%. The addition of QG increased the efficacy by 18.24% and 8.03%, respectively, at florescence and the young fruit stage. The addition of the LD increased the efficacy by 24.56% and 14.38%, respectively, at florescence and the young fruit stage. These test results can provide a scientific basis for the control of mango thrips with UAVs
Longitudinal Analysis of Fecal Microbiome and Pathologic Processes in a Rotenone Induced Mice Model of Parkinson’s Disease
Recent studies reported an association between gut microbiota composition and Parkinson’s disease (PD). However, we know little about the relationship between microbiome dysbiosis and the pathogenesis of PD. The objective of this study was to describe the evolution of fecal microbiota using an oral rotenone model of PD from a longitudinal study over a period of 4 weeks. Gastrointestinal function was assessed by measuring fecal pellet output, motor functions was assessed by open-field and pole tests every week. α-synuclein pathology, inflammation and tyrosine hydroxylase (TH) neuron loss from the middle brain were also analyzed. Fecal samples were collected every week followed by 16S rRNA sequencing and bioinformatics analysis. We reported that chronically oral administered rotenone caused gastrointestinal dysfunction and microbiome dysbiosis prior to motor dysfunction and central nervous system (CNS) pathology. 16S rRNA sequencing of fecal microbiome showed rotenone-treated mice exhibited fecal microbiota dysbiosis characterized by an overall decrease in bacterial diversity and a significant change of microbiota composition, notably members of the phyla Firmicutes and Bacteroidetes, with an increase in Firmicutes/Bacteroidetes ratio after 3 weeks of rotenone treatment. Moreover, rotenone-induced gastrointestinal and motor dysfunctions were observed to be robustly correlated with changes in the composition of fecal microbiota. Our results demonstrated that gut microbiome perturbation might contribute to rotenone toxicity in the initiation of PD and brought a new insight in the pathogenesis of PD. Novel therapeutic options aimed at modifying the gut microbiota composition might postpone the onset and following cascade of neurodegeneration
Quantifying urban mass gain and loss by a GIS-based material stocks and flows analysis
Rapid urbanization generates substantial demand, use, and demolition waste of construction materials. However, the existing top-down or bottom-up frameworks combining material flow analysis (MFA) and geographic information system (GIS) tend to underestimate both input and output of construction material flows due to insufficient descriptions of key processes in building construction and demolition. To address this limitation, this study identifies four important and complementary processes—construction, demolition, replacement, and maintenance, and integrates them into an improved framework to capture all material flows. We take Xiamen, a rapidly urbanizing city, as a case study to verify this framework. The results show that ∼40% of material inputs and ∼65% of outputs are underestimated by previous frameworks because they fail to capture material inputs in building maintenance and outputs in construction. These findings indicate a better estimation of such key flows in the modeling framework helps to accurately characterize building material metabolism. Based on systematic counting of material stocks and flows, the improved framework can help design effective policies for urban resource management by explicitly recognizing the spatiotemporal patterns and processes of material metabolism
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