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Spin effect on redox acceleration and regioselectivity in Fe-catalyzed alkyne hydrosilylation

National Science Review 2024年第2期11卷 155-167页

作者： Peng He Meng-Yang Hu jin-hong li Tian-Zhang Qiao Yi-lin Lu Shou-Fei Zhu Frontiers Science Center for New Organic Matter State Key Laboratory and Institute of Elemento-Organic Chemistry Nankai University

Iron catalysts are ideal transition metal catalysts because of the Earths abundant, cheap, biocompatible features of iron salts. Iron catalysts often have unique open-shell structures that easily undergo spin crossover in chemical transformations, a feature rarely found in noble metal catalysts. Unfortunately, little is known currently about how the open-shell structure and spin crossover affect the reactivity and selectivity of iron catalysts, which makes the development of iron catalysts a low efficient trial-and-error program. In this paper, a combination of experiments and theoretical calculations revealed that the iron-catalyzed hydrosilylation of alkynes is typical spin-crossover catalysis. Deep insight into the electronic structures of a set of well-defined open-shell active formal Fe(0) catalysts revealed that the spin-delocalization between the iron center and the 1,10-phenanthroline ligand effectively regulates the iron center's spin and oxidation state to meet the opposite electrostatic requirements of oxidative addition and reductive elimination, respectively,and the spin crossover is essential for this electron transfer process. The triplet transition state was essential for achieving high regioselectivity through tuning the nonbonding interactions. These findings provide an important reference for understanding the effect of catalyst spin state on reaction. It is inspiring for the development of iron catalysts and other Earth-abundant metal catalysts, especially from the point of view of ligand development.

关键词： spin effect spin-delocalization spin crossover iron-catalysis alkyne hydrosilylation

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A Criterion for the Generalized Riemann Hypothesis

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Acta Mathematica Sinica,English Series 2009年第11期25卷 1875-1880页

作者： jin hong li School of Mathematics Shandong University Ji'nan Shandong 250100 P. R. China College of Mathematics and Physics Shandong Institute of Light Industry Ji'nan Shandong 250353 P. R. China

In this paper, we study the automorphic L-functions attached to the classical automorphic forms on GL（2）, i.e. holomorphic cusp form. And we also give a criterion for the Generalized Riemann Hypothesis （GRH） for t... 详细信息

关键词： GRH L-function holomorphic cusp form

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K-19 mRNA RT-PCR in detecting micrometastasis in regional lymph nodes of gastric cancer

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World Journal of Gastroenterology 2006年第32期12卷 5219-5222页

作者： Jian Suo Quan Wang hong-Juan jin hong li Hang Zhao Department of General Surgery First Hospital Changchun 130021 Jilin Province China

AIM： To investigate the value and prospect of RT-PCR in detecting micrometastasis in regional lymph nodes of gastric cancer. METHODS： Histopathology was used and K19 mRNA expression was detected by RT-PCR in tumor tissues and lymph nodes from gastric cancer patients undergoing radical resection of gastric carcinoma. RESULTS： K19 mRNA was expressed in all tumor specimens of 30 cases; of the 126 lymph nodes, 26 were histopathologically positive （20.6%）, and 42 positive （33.3%） by RT-PCR. Amplification fragments of 460 and 540 bp were shown in all the tumor tissues and metastatic lymph nodes after K19 and β-actin RT-PCR, while only a 540 bp fragment appeared in the lymph nodes of non-tumor patients. CONCLUSION： K19 mRNA RT-PCR is sensitive and specific in testing micrometastasis in regional lymph nodes of gastric cancer, and it is superior to routine histopathology.

关键词： K-19 mRNA RT-PCR Micrometastasis Gastric cancer

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The Role of Calcium in Mediating SliAAs Expression in Tomato Pedicel Explants

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Agricultural Sciences in China 2010年第7期9卷 980-984页

作者： ZUO Xian-hong XU Tao QI Ming-fang LU Shuang-shuang li jin-hong li hong GAO Song li Tian-lai Key Laboratory of Protected Horticulture of liaoning Province/College of Horticulture Shenyang Agricultural University Shenyang 110161 P.R. China

In order to illuminate the effect of calcium on the IAA signal transduction,we studied the expression of eight SliAA genes which were up-regulated by calcium during the abscission after short-term（1 h） and long-term（16 h） treatments with calcium,IAA and calcium *** results indicated that calcium induced SliAAs expression in 1 h at low concentration,EGTA affected little SliAAs expression;it also increased IAA-induced transcript level of SliAAs,TFP（named trifluoperazine） decreased most SliAAs expression below the level of calcium combined with IAA-induced expression,except for ***-term treatment of calcium or calcium inhibitors suppressed some SliAAs expression,whereas TFP enhanced all SliAAs ***,SliAA29 was induced by most treatments excluding 16 h EGTA.

关键词： tomato calcium IAA calcium inhibitors SIlAA gene

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Video caching and scheduling with edge cooperation

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Digital Communications and Networks 2024年第2期10卷 450-460页

作者： Zhidu li Fuxiang li Tong Tang hong Zhang jin Yang School of Communication and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing400065China Advanced Network and Intelligent Connection Technology Key Laboratory of Chongqing Education Commission of China Chongqing400065China Key Laboratory of Ubiquitous Sensing and Networking in Chongqing Chongqing400065China

In this paper,we explore a distributed collaborative caching and computing model to support the distribution of adaptive bit rate video *** aim is to reduce the average initial buffer delay and improve the quality of user *** the difference between global and local video popularities and the time-varying characteristics of video popularity,a two-stage caching scheme is proposed to push popular videos closer to users and minimize the average initial buffer *** on both long-term content popularity and short-term content popularity,the proposed caching solution is decouple into the proactive cache stage and the cache update *** the proactive cache stage,we develop a proactive cache placement algorithm that can be executed in an off-peak *** the cache update stage,we propose a reactive cache update algorithm to update the existing cache policy to minimize the buffer *** results verify that the proposed caching algorithms can reduce the initial buffer delay efficiently.

关键词： Video service Distributed and collaborative caching Long-term popularity Short-term popularity

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Differential diagnosis and laparoscopic treatment of adrenal pheochromocytoma and ganglioneuroma

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Chinese Medical Journal 2009年第15期122卷 1790-1793页

作者： SHI Bing-bing li Han-zhong CHEN Cheng RONG Shi FAN Hua WEN jin li hong-jun Department of Urology Peking Union Medical College Hospital Chinese Academy of Medical Sciences Beijing 100730 China

Background Adrenal ganglioneuroma is a rare adrenal pathogenic disease with difficult differential diagnosis from adrenal pheochromocytoma. Currently, very limited literature is available to allow a differential diagnosis of these two conditions from each other. This study aimed to evaluate the clinical profile, differential diagnosis and surgical treatments of both conditions. Methods Clinical characteristics of 36 patients with adrenal pheocheomocytoma and 18 patients with adrenal ganglioneuroma were analyzed. Data from CT scans and surgical treatments from 1999 to 2007 were collected. Endocrine hormone tests and ^131I-metaiodobenzylguanidine （MIBG） were performed. Neither ^131I-MIBG nor endocrine hormone tests were available in 9 cases of asymptomatic adrenal ganglioneuroma with tumor size less than 4 cm and there were negative findings from contrast enhanced CT scans. The level of urine catecholamine of patients was compared by one-way analysis of variance. Results The mean age of patients in the adrenal ganglioneuroma group was 41.2 years （16-67 year） and in the adrenal pheochromocytoma patients 38 years （17-74 year）. Contrast enhanced CT showed that the foci were intensified in 5 cases （27.8%） of adrenal ganglioneuroma and there were obvious contrast indications in 30 （83.3%） of the pheochromocytoma. Catecholamine levels in a 24-hour urine sample were normal in 4 patients with adrenal ganglioneuroma and increased in 36 （100%） cases with adrenal pheochromocytoma. ^131I-MIBG nuclear scan showed negative results in 4 patients （100%） with adrenal ganglioneuroma and positive results in 25 （96.2%） with adrenal pheochromocytom. Laparoscopy for adrenal tumors was performed through a transperitoneal or retroperitoneal approach during a follow-up period of （43±6） months, and all cases survived well. Conclusions CT, urinary catecholamine and ^131I-MIBG are standard and efficient tools for differential diagnosis of adrenal ganglioneuroma from pheochromocytoma. Laparoscopi

关键词： pheochromocytoma ganglioneuroma, laparoscopy

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Nicotinamide adenine dinucleotide treatment confers resistance to neonatal ischemia and hypoxia:effects on neurobehavioral phenotypes

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Neural Regeneration Research 2024年第12期19卷 2760-2772页

作者： Xiaowen Xu Xinxin Wang li Zhang Yiming jin lili li Meifang jin lianyong li hong Ni Division of Brain Science Institute of Pediatric ResearchChildren’s Hospital of Soochow UniversitySuzhouJiangsu ProvinceChina Department of Pediatric Orthopedics Shengjing Hospital of China Medical UniversityShenyangLiaoning ProvinceChina

Neonatal hypoxic-ischemic brain injury is the main cause of hypoxic-ischemic encephalopathy and cerebral ***,there are few effective clinical treatments for neonatal hypoxic-ischemic brain ***,we investigated the neuroprotective and molecular mechanisms of exogenous nicotinamide adenine dinucleotide,which can protect against hypoxic injury in adulthood,in a mouse model of neonatal hypoxic-ischemic brain *** this study,nicotinamide adenine dinucleotide(5 mg/kg)was intraperitoneally administered 30 minutes befo re surgery and every 24 hours *** results showed that nicotinamide adenine dinucleotide treatment improved body weight,brain structure,adenosine triphosphate levels,oxidative damage,neurobehavioral test outcomes,and seizure threshold in experimental *** mass tag proteomics revealed that numerous proteins were altered after nicotinamide adenine dinucleotide treatment in hypoxic-ischemic brain injury *** reaction monitoring and western blotting confirmed changes in the expression levels of proteins including serine(or cysteine)peptidase inhibitor,clade A,member 3N,fibronectin 1,5'-nucleotidase,cytosolic IA,microtubule associated protein 2,and complexin *** analyses showed that nicotinamide adenine dinucleotide ameliorated hypoxic-ischemic injury through inflammation-related signaling pathways(e.g.,nuclear factor-kappa B,mitogen-activated protein kinase,and phosphatidylinositol 3 kinase/protein kinase B).These findings suggest that nicotinamide adenine dinucleotide treatment can improve neurobehavioral phenotypes in hypoxic-ischemic brain injury mice through inflammation-related pathways.

关键词： brain injury cerebral palsy hypoxia hypoxic-ischemic brain injury inflammation neuroprotection nicotinamide adenine dinucleotide neonate nicotinamide adenine dinucleotide proteomics

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Effect of Wheat Middlings, Microbial Phytase, and Citric Acid on Phytate-Phosphorus, Calcium, and Protein Utilization of Broilers

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Agricultural Sciences in China 2006年第4期5卷 318-322页

作者： GONG Yi-feng liAO He-rong WANG jin-fu li hong-yan Department of Animal Science and Technology Shihezi University Shihezi 832003 P.R.China

A corn-soybean meal diet （CSB）（or Diet 1） containing 23% crude protein （CP） was used as the positive control, and another corn-soybean meal diet containing 21% CP and 15% wheat middlings （WM）（or Diet 2） was used as the basal diet, which was treated with four different treatments. Digestibility experiment was employed to discuss the collective effect of citric acid, and intrinsic and microbial phytase. By comparing and analyzing effects of them in the low-nutrient broiler diets, the results showed five treatments had similar effects on Tibia ash （%）（mg）（P〉0.05）. Under the supplementation of bacterial phytase or citric acid, the daily body weight gain （ADG）, gain：feed （G：F） ratio, and calcium （Ca） utilization were similar to that of standard-nutrient CSB diet （Diet 1）（P 〉 0.05）. And, fecal phosphorus （P） and CP utilization were lower than （P〈0.05） that of Diet 1. But P utilization was significantly higher than （P〈0.01） that of Diet 1. However, the ADG, G：F, and CP utilization produced by supplementation of intrinsic phytase were lower than those of Diet 1, but other aspects were similar to those produced by Diet 1 （P〉0.05）. In Diet 5, citric acid, intrinsic and bacterial phytase were added to the diet, which produced a 1.4% decrease on fecal P, a 7.2% increase on Ca utilization, which was significantly higher than （P〈0.01） those of the other four Diets, a 3.9% increase on G：F, which was similar to that of Diet 1, and a 2.3% increase on CP utilization, which was higher than （P〈0.05） that of the other three diets. In summary, the results of this study indicated that citric acid, intrinsic and bacterial phytase might have some additive or synergistic effects, and low-nutrient CSB diets with 15% wheat middlings, 750 U kg^-1 phytase, and 3% citric acid might substitute completely for standard CSB in broilers.

关键词： broilers phytase citric acid calcium phosphorus protein

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Media Power Measuring via Emotional Contagion

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Journal of Social Computing 2024年第1期5卷 15-35页

作者： Xue lin hong Huang Zongya li Hai jin National Engineering Research Center for Big Data Technology and System Services Computing Technology and System LabCluster and Grid Computing LabSchool of Computer Science and TechnologyHuazhong University of Science and TechnologyWuhan 430074China School of Journalism Huazhong University of Science and TechnologyWuhan 430074China

Media power,the impact that media have on public opinion and perspectives,plays a significant role in maintaining internal stability,exerting external influence,and shaping international dynamics for nations/***,prior research has primarily concentrated on news content and reporting time,resulting in limitations in evaluating media *** more accurately assess media power,we use news content,news reporting time,and news emotion simultaneously to explore the emotional contagion between *** use emotional contagion to measure the mutual influence between media and regard the media with greater impact as having stronger media *** propose a framework called Measuring Media Power via Emotional Contagion(MMPEC)to capture emotional contagion among media,enabling a more accurate assessment of media power at the media and national/regional *** also interprets experimental results through correlation and causality analyses,ensuring *** analyses confirm the higher accuracy of MMPEC compared to other baseline models,as demonstrated in the context of COVID-19-related news,yielding compelling and interesting insights.

关键词： explainability media power emotional contagion

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Multiplicity of solutions for the semilinear subelliptic Dirichlet problem

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Science China Mathematics 2024年第3期67卷 475-504页

作者： Hua Chen hong-Ge Chen jin-Ning li Xin liao School of Mathematics and Statistics Wuhan UniversityWuhan 430072China Wuhan Institute of Physics and Mathematics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China

In this paper,we study the semilinear subelliptic equation{−△Xu=f(x,u)+g(x,u)inΩ,u=0 on∂Ω,where△X=−∑m i=1 Xi∗Xi is the self-adjoint Hormander operator associated with the vector fields X=(X_(1),X_(2),...,X_(m))satisfying the Hormander's condition,f(x,u)∈C(Ω×R),g(x,u)is a Carathéodory function onΩ×R,andΩis an open bounded domain in R~n with smooth *** the perturbation from the symmetry method with the approaches involving the eigenvalue estimate and the Morse index in estimating the minimax values,we obtain two kinds of existence results for multiple weak solutions to the problem ***,we discuss the difference between the eigenvalue estimate approach and the Morse index approach in degenerate *** with the classical elliptic cases,both approaches here have their own strengths in the degenerate *** new phenomenon implies that the results in general degenerate cases would be quite different from the situations in classical elliptic cases.

关键词： degenerate elliptic equations Hormander operators perturbation method Morse index

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