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science China Chemistry 2024年第11期67卷 3791-3797页

作者： Debasis Pal Kirana D.Veeranna yuk Fai wong P.Andrew Evans Department of Chemistry Queen's University Xiangya school of Pharmaceutical sciences Central South University

The Reformatsky reagent derived from ethyl bromoacetate circumvents the challenge associated with the direct regio-and enantioselective iridium-catalyzed allylic alkylation with an unstabilized aliphatic ester enolate. Notably, this work represents the first example of using a Reformatsky reagent in a metal-allyl reaction, which permits the direct construction of enantioenriched β-stereogenic homoallylic esters without preactivation of the pronucleophile or post-reaction modification of the product(e.g., thermal decarboxylation of a 1,3-dicarbonyl). Moreover, the process allows the coupling of a broad range of sterically and electronically diverse electrophiles bearing aryl, heteroaryl and alkenyl derivatives, including the significantly more challenging alkyl-substituted allylic carbonates. The versatility of the ester product is exemplified by a series of functional group manipulations and the development of a concise and efficient enantioselective total synthesis of the natural product,(+)-descurainolide A. Finally, mechanistic studies indicate that the zinc enolate behaves as a soft nucleophile that undergoes outer-sphere alkylation.

关键词： allylic substitution asymmetric catalysis mechanistic studies natural product synthesis Reformatsky reagent

Tribological evaluation of thermoplastic polyurethane-based bearing materials under water lubrication:Effect of load,sliding speed,and temperature

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Friction 2024年第8期12卷 1801-1815页

作者： shaoli JIANG Janet sswong Debashis PUHAN Tian yUAN Xiuqin BAI Chengqing yUAN state Key Laboratory of Maritime Technology and safety Wuhan University of TechnologyWuhan 430063China Department of Mechanical Engineering Imperial College LondonLondon SW72AZUK y.s.f Hamied Department of Chemistry University of CambridgeLensfield RoadCambridge CB21EWUK

Polymers are widely used in bearing *** the case of water-lubricated stern tube bearings,thermoplastic polyurethane(TPU)-based composites are used due to their excellent wear resistance,corrosion resistance,and tunable mechanical *** tribological performance,however,depends on operating *** this work,TPU was blended with carbon fiber,graphene platelet,and ultra-high molecular weight polyethylene(UHMWPE).Friction tests of TPU based-composites against copper countersurface were carried out in water to mimic the actual operating conditions of the *** of the resulting contacts were in the boundary lubrication regime,in which friction was attributed to both contact mechanics of asperities as well as water *** results show that the viscoelasticity of TPU has a considerable impact on its tribological *** lubrication at 50°C promotes the softening of polymer surface material during sliding,resulting in higher fluctuation in the coefficient of friction and wear *** is attributed to the reduced thermomechanical *** addition,schallamach waviness is observed on worn *** tribological properties of TPU are significantly improved by the inclusion of carbon fiber,graphene platelet,and *** formation of graphene transfer-layers and UHMWPE transfer film reduces friction and wear loss,while the inclusion of carbon fiber enhances wear resistance due to improved mechanical properties and load bearing capacity.

关键词： friction thermoplastic polyurethane(TPU) water-lubricated bearings graphene platelet carbon fibers ultra-high molecular weight polyethylene(UHMWPE)

Missed Pancreaticobiliary Malignancy: The Flaw of the Expedited Cholecystectomy

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surgical science 2024年第7期15卷 451-464页

作者： Dylan s. Goto Larissa Fujii-Lau Linda L. wong Department of surgery John A. Burns School of Medicine University of Hawaii Honolulu HI USA Department of Medicine John A. Burns School of Medicine University of Hawaii Honolulu HI USA

Background: Early cholecystectomy has been recommended for patients with acute cholecystitis and gallstone pancreatitis. However, patients with pancreaticobiliary malignancy may present acutely with similar symptoms. We hypothesize that the diagnoses of these malignancies may potentially be delayed as an unintended consequence of expedited cholecystectomies. This study reviews a cohort of patients who underwent pancreaticoduodenectomy (PD) to identify those who underwent a separate cholecystectomy before their PD. Methods: We retrospectively reviewed 162 PDs performed between 2012 and 2022. Data collected included: demographics, disease etiology and the presence of cholelithiasis. We identified patients who had a previous cholecystectomy and the time elapsed before PD as well as procedures done during the interval. We reported detailed case summaries on those patients who had a cholecystectomy within 1 year of PD. Results: In the entire cohort, mean age was 65 years, 54% were males, and 83% had a malignant reason for PD. Thirty-one patients had cholelithiasis with 23 (14%) patients having had previous cholecystectomy. six patients had cholecystectomy within 1 year of PD. They had the following malignancies: ampullary—3, pancreas—1, cholangiocarcinoma—1 and neuroendocrine—1. Four of these patients had expedited cholecystectomy on their index hospital admission and were later found to have a periampullary malignancy with further work up. Conclusions: Pancreaticobiliary malignancies can be difficult to diagnose, and surgeons should not overlook these potential diagnoses when considering expedited cholecystectomy. Future studies in large cohorts are needed to identify high risk candidates who should undergo more detailed testing to exclude malignancy before proceeding with cholecystectomy.

关键词： Cholecystectomy Periampullary Malignancy Pancreas Malignancy Pancreaticoduodenectomy

Aquaculture species diversification in China

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Aquaculture and Fisheries 2024年第2期9卷 206-217页

作者： Gen Hua yue yi Xuan Tay Joey wong yubang shen Junhong Xia Temasek Life sciences Laboratory National University of Singapore1 Research Link117604Singapore Key Laboratory of Freshwater Aquatic Genetic Resources Ministry of Agriculture and Rural AffairsShanghai Ocean UniversityShanghai201306China state Key Laboratory of Biocontrol Institute of Aquatic Economic Animals and Guangdong Provincial Key Laboratory for Aquatic Economic AnimalsCollege of Life SciencesSun Yat-Sen UniversityGuangzhou510275China

China has been the top aquaculture producer in the world since *** 800 species and 240 improved varieties have been used in China’s aquaculture,which is the most diverse collection of species on this *** diversification,along with other aquaculture technologies,contributes significantly to the increase of China’s aquaculture production,whereas the use of too many.s.ecies in aquaculture has resulted in some issues related to the environment and *** provide an updated overview of the species currently used in Chinese aquaculture in this *** examine critically the main drivers of species diversification in China with *** also introduce Chinese approaches to improve and certify new species and varieties for commercial *** believe that further species diversification is not a priority in China’s aquaculture,while further improvement of aquaculture technologies for major and native species is essential for green,profitable,and sustainable(GPs)*** implications of China’s experiences with species diversification for global aquaculture species diversification are discussed.

关键词： Fish species Diversification Improvement Future

MXenes and heterostructures-based electrocatalysts for hydrogen evolution reaction:Recent developments and future outlook

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Journal of Energy Chemistry 2024年第5期92卷 176-206页

作者： Abdul Hanan Hafiz Taimoor Ahmed Awan Faiza Bibi Raja Rafidah Raja sulaiman Wai yin wong Rashmi Walvekar seema singh Mohammad Khalid sunway Centre for Electrochemical Energy and sustainable Technology.s.EEsT) School of Engineering and TechnologySunway UniversityNo.5 Jalan UniversitiBandar Sunway47500 Petaling JayaSelangorMalaysia Fuel Cell Institute Universiti Kebangsaan Malaysia43600 UKM BangiSelangorMalaysia Faculty of Innovation and Technology School of EngineeringChemical Engineering ProgrammeNo.1 Jalan Taylor’sTaylor’s University Malaysia47500 Subang JayaSelangorMalaysia Chitkara Centre for Research and Development Chitkara UniversityHimachal Pradesh 174103India school of Applied and Life sciences Uttaranchal UniversityDehradunUttarakhand 248007India Manipal Institute of Technology Manipal Academy of Higher EducationManipal 576104KarnatakaIndia Centre of Research Impact and Outcome Chitkara UniversityPunjab 140401India

The increasing focus on electrocatalysis for sustainable hydrogen(H_(2))production has prompted significant interest in MXenes,a class of two-dimensional(2D)materials comprising metal carbides,carbonitrides,and *** materials exhibit intriguing chemical and physical properties,including excellent electrical conductivity and a large surface area,making them attractive candidates for the hydrogen evolution reaction(HER).This scientific review explores recent advancements in MXene-based electrocatalysts for HER *** discusses various compositions,functionalities,and explicit design principles while providing a comprehensive overview of synthesis methods,exceptional properties,and electro-catalytic approaches for H_(2) production via electrochemical ***,challenges and future prospects in designing MXenes-based electrocatalysts with enhanced kinetics are highlighted,emphasizing the potential of incorporating different metals to expand the scope of electrochemical *** review suggests possible efforts for developing advanced MXenes-based electrocatalysts,particularly for efficient H_(2) generation through electrochemical water-splitting reactions..

关键词： MXenes Electrocatalyst Water splitting Hydrogen Generation Clean Energy

Unsynchronized butyrophilin molecules dictate cancer cell evasion of Vγ9Vδ2 T-cell killing

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Cellular & Molecular Immunology 2024年第4期21卷 362-373页

作者： Zeguang Wu Qiezhong Lamao Meichao Gu Xuanxuan Jin ying Liu Feng Tian ying yu Pengfei yuan shuaixin Gao Thomas s.Fulford Adam P.Uldrich Catherine C.L wong Wensheng Wei Biomedical Pioneering Innovation Center Peking-Tsinghua Center for Life SciencesPeking University Genome Editing Research CenterState Key Laboratory of Protein and Plant Gene ResearchSchool of Life SciencesPeking University100871BeijingChina EdiGene Inc. Life Science ParkChangping District102206BeijingChina Center for Precision Medicine Multi-Omics Research Peking University Health Science CenterPeking University100191BeijingChina Department of Microbiology and Immunology at the Peter Doherty Institute for Infection and Immunity The University of MelbourneParkvilleVIC3010Australia Cancer Immunology Program Peter MacCallum Cancer CentreMelbourneVICAustralia state Key Laboratory for Complex Severe and Rare DiseasesClinical Research InstitutePeking Union Medical College HospitalChinese Academy of Medical Science&Peking Union Medical CollegePeking-Tsinghua Center for Life Sciences100871BeijingChina

Vγ9Vδ2 T cells are specialized effector cells that have gained prominence as immunotherapy agents due to their ability to target and kill cells with altered pyrophosphate *** our effort to understand how cancer cells evade the cell-killing activity of Vγ9Vδ2 T cells,we performed a comprehensive genome-scale CRIsPR screening of cancer *** found that four molecules belonging to the butyrophilin(BTN)family.s.ecifically BTN2A1,BTN3A1,BTN3A2,and BTN3A3,are critically important and play unique,nonoverlapping roles in facilitating the destruction of cancer cells by primary Vγ9Vδ2 T *** coordinated function of these BTN molecules was driven by.s.nchronized gene expression,which was regulated by IFN-γsignaling and the RFX ***,an enzyme called QPCTL was shown to play a key role in modifying the N-terminal glutamine of these BTN proteins and was found to be a crucial factor in Vγ9Vδ2 T cell killing of cancer *** our research,we offer a detailed overview of the functional genomic mechanisms that underlie how cancer cells escape Vγ9Vδ2 T ***,our findings shed light on the importance of the harmonized expression and function of gene family members in modulating T-cell activity.

关键词： Butyrophilin Vγ9Vδ2 T-cell Cancer-specific immune evasion Glutaminyl-peptide cyclotransferase-like Pyrophosphate metabolite Immunotherapy

Experimental evaluation of a“U”type earth-to-air heat exchanger planned for narrow installation space in warm climatic conditions

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Energy and Built Environment 2024年第5期5卷 772-786页

作者： Ricardo Molina-Rodea Jorge Alejandro wong-Loya Hugo Pocasangre-Chávez Jennifer Reyna-Guillén Institute of Renewable Energies National Autonomous University of MexicoTemixcoMorelosMexico

The thermal performance of a“U”type earth-to-air heat exchanger is presented in this experimental *** device has a serial-connected vertical *** wells where tubes were installed have a depth of fewer than 3 m and are separated every 1.5 m,using an installation area of *** experimentation was carried out in March in Morelos,Mexico when the environmental temperature reaches 35℃ during the *** performance of the device was measured and compared to the requirements of an office for cooling purposes within a university campus to reproduce the space restrictions found in urbanized *** using a small land surface,it is feasible for urbanized *** air temperature inside the“U”type earth-to-air heat exchanger,the surrounding soil temperature,the airspeed,and the power consumed by the fan were *** air temperature and the fan’s power consumption data were obtained by modifying the airspeed in four constant values,from 1.3 m/s to 6.6 m/*** show that the device evaluated in this work has adequate thermal performance for cooling purposes compared to the requirements of an office.A decrease in air temperature was recorded in a range of 5.1℃ to 9.4℃.Over 70%of the total temperature difference was reached in the first well,where the average soil thermal disturbance at 5 cm was 2.8℃.The device achieved a maximum COP of 12.8 and a maximum effectiveness of 88.4%.With these results,it is concluded that the system is suitable for cooling purposes in areas with space *** work is novel since the dimensions available for installation in urbanized areas are considered and compared with the thermal requirements of an *** addition to the fact that there are no published works with vertical heat exchangers connected in series.

关键词： Low temperature geothermal energy Thermal performance Vertical heat exchangers space restrictions in urbanized areas Geothermal direct uses

Quantum Realities and Observer-Dependent Universes: An Advanced Observer Model

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Journal of Quantum Information science 2024年第3期14卷 69-121页

作者： Joseph Hon Cheung wong Department of Computing The Hong Kong Polytechnic University Hung Hom Kowloon Hong Kong China

This paper presents a novel observer model that integrates quantum mechanics, relativity, idealism, and the simulation hypothesis to explain the quantum nature of the universe. The model posits a central server transmitting multi-media frames to create observer-dependent realities. Key aspects include deriving frame rates, defining quantum reality, and establishing hierarchical observer structures. The model’s impact on quantum information theory and philosophical interpretations of reality are examined, with detailed discussions on information loss and recursive frame transmission in the appendices.

关键词： Quantum Mechanics Observer Model Frame Rates Quantum Reality Hierarchical Observers Information Theory simulation Hypothesis Recursive Frame Transmission Information Loss

Males armed with big weapons win fights at limited cost in ant-mimickingjumping spiders

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Current Zoology 2024年第1期70卷 98-108页

作者： Guocheng yu Boon Hui wong Christina J.Painting Hongze Li Long yu Zengtao Zhang shichang Zhang Daiqin Li state Key Laboratory of Biocatalysis and Enzyme Engineering and Centre for Behavioral Ecology and Evolution School of Life SciencesHubei UniversityWuhan430062China Departmentof Biological sciences National University of Singapore14 Science Drive 4Singapore 117543Singapore Te Aka Matuatua school of science University of WaikatoPrivate Bag 3105Hamilton 3240New Zealand

A core assumption of sexual selection theory is that sexually.s.lected weapons,specialized morphological structures used directly in male con-tests,can improve an individual's reproductive success but only if the bearer can overcome associated costs,the negative effects on the bear-er's fitness ***,recent studies have shown that producing and wielding exaggerated weapons may not necessarily be ***,some traits can be selected for supporting,or compensating for,the expense of producing and wielding such exaggerated weapons.n the ant-mimicking jumping spider Myrmarachne gisti,exaggerated chelicerae are borne only by adult males and not females,showing sexual dimorphism and steep positive allometry with body ***,we determine the potential benefits of bearing exaggerated chelicerae during male contests and explore the potential for costs in terms of prey-capture efficiency and compensation between chelicera size and neighboring trait *** males with longer chelicerae won most of their male-male contests,we found no significant differences in prey-capture effi-ciency between males and females regardless of whether prey was winged or ***'elongated chelicerae thus do not impede their efficiency at capturing ***,we found that the sizes of all neighboring traits are positively correlated with chelicera size,suggesting that these traits may be under correlational *** together,our findings suggest that *** males armed with the exaggerated chelicerae that function as weapons win more fights at limited cost for performance in prey capture and compensate for neighboring structures.

关键词： allometry ant-mimic costs elongated chelicerae threat devices trait compensations

Genomics-driven derivatization of the bioactive fungal sesterterpenoid variecolin:Creation of an unnatural analogue with improved anticancer properties

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Acta Pharmaceutica sinica B 2024年第1期14卷 421-432页

作者： Dexiu yan Jemma Arakelyan Teng Wan Ritvik Raina Tsz Ki Chan Dohyun Ahn Vladimir Kushnarev Tsz Kiu Cheung Ho Ching Chan Inseo Choi Pui yi Ho Feijun Hu yujeong Kim Hill Lam Lau ying Lo Law Chi seng Leung Chun yin Tong Kai Kap wong Wing Lam yim Nikolay.s.Karnaukhov Richard y.C.Kong Maria V.Babak yudai Matsuda Department of Chemistry City University of Hong KongHong Kong SARChina iGEM Team“VarieCure” City University of Hong KongHong Kong SARChina Department of Biomedical Engineering City University of Hong KongHong Kong SARChina Moscow Clinical Research Center Named After A.s.Loginov Moscow 111123Russian Federation

A biosynthetic gene cluster for the bioactive fungal sesterterpenoids variecolin(1)and variecolactone(2)was identified in Aspergillus aculeatus ATCC *** production of 1 and 2 was achieved in Aspergillus oryzae by expressing the sesterterpene synthase VrcA and the cytochrome P450 ***,the replacement of VrcB with homologous P450s from other fungal terpenoid pathways yielded three new variecolin analogues(5-7).Analysis of the compounds’anticancer activity in vitro and in vivo revealed that although 5 and 1 had comparable activities,5 was associated with significantly reduced toxic side effects in cancer-bearing mice,indicating its potentially broader therapeutic *** study describes the first tests of variecolin and its analogues in animals and demonstrates the utility of synthetic biology for creating molecules with improved biological activities.

关键词： Animal studies Anticancer properties Biosynthesis Natural products sesterterpenoids synthetic biology Terpene synthases Variecolin