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Insect Science 2025年第1期32卷 290-300页

作者： Ke Gao Wout van der Heide Daphne Muijderman Sarah Nichols Carmen Karwal peter Kuperus Astrid t.Groot Institute for Biodiversity and Ecosystem Dynamics University of AmsterdamAmsterdamthe Netherlands Department of Cell and Developmental Biology University of California San DiegoLa JollaCaliforniaUSA Department of Neurobiology and Behavior Cornell UniversityIthacaNew YorkUSA University of Leiden Leidenthe Netherlands

Given the limited availability of resources in nature,sexual attractiveness may trade off with immunocompetence,as the immunocompetence handicap hypothesis(ICHH)*** invertebrates,a direct link between trade-offs through hormonal/molecular effectors in sexual signals and immunity has not been found so ***,we assessed how variation in sexual signals affected parasite infection in two sex pheromone selected lines of the moth Chloridea virescens:an attractive line with a low ratio of 16:Ald/Z11-16:Ald and an unattractive line with a high *** infecting these lines with an apicomplexan parasite,we found that the attractive Low line was significantly more susceptible to the parasite infection than the unattractive High *** the ratio difference between these two lines is determined by a delta-11-desturase,we hypothesized that this desaturase may have a dual role,i.e.,in the quality of the sexual signal as well as an involvement in immune response,comparable to testosterone in ***,when we used CRISPR/cas9 to knockout delta-11-desturase in the attractive Low line,we found that the pheromonal phenotype did change to that of the High line,but the infection susceptibility did ***,when checking the genomic location of delta-11-desaturase in the ***,we found that mucin is adjacent to *** comparing the mucin sequences in both lines,we found four nonsynonymous SNPs in the coding sequence,as well as intronic variation between the two *** differences suggest that genetic hitchhiking may explain the variation in susceptibility to parasitic infection.

关键词： Chloridea virescens delta-11-desaturase ICHH parasite susceptibility sex pheromone

the evolution and refinement of vasoepididymostomy techniques

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Asian Journal of Andrology 2013年第1期15卷 49-55页

作者： peter t Chan Department of Urology Royal Victoria Hospital McGill University Health Center Montreal Quebec H3A 1A1 Canada

Obstructive azoospermia secondary to epididymal obstruction can be corrected by microsurgical reconstruction with vasoepididymostomy （VE）. Although alternative management such as epididymal or testicular sperm aspiration in conjunction with intracytoplasmic sperm injection is feasible, various studies have established the superior cost-effectiveness of VE as a treatment of choice. Microsurgical VE is considered one of the most technically challenging microsurgeries. Its success rate is highly dependent on the skills and experience of the surgeons. Various techniques have been described in the literature for VE. We have pioneered a technique known as longitudinal intussusception VE （LIVE） in which the epididymal tubule is opened longitudinally to obtain a larger opening to allow its tubular content to pass through the anastomosis. Our preliminary data demonstrated a patency rate of over 90%. this technique has been widely referenced in the recent literature including robotic-assisted microsurgery. the history of the development of different VE approaches, the oreoDerative evaluation along with the techniaues of various VE will be described in this article.

关键词： longitudinal intussusception vasoepididymostomy (LIVE) intracytoplasmic sperm injection (ICSI) male infertility microsurgery obstructive azoospermia vasoepididymostomy (VE)

Imaging in translational cancer research

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Cancer Biology & Medicine 2022年第11期19卷 1565-1585页

作者： Felix t.Kurz Heinz-peter Schlemmer Department of Radiology German Cancer Research CenterHeidelberg 69120Germany

this review is aimed at presenting some of the recent developments in translational cancer imaging research,with a focus on novel,recently established,or soon to be established cross-sectional imaging techniques for computed tomography(Ct),magnetic resonance imaging(MRI),and positron-emission tomography(PEt)imaging,including computational investigations based on machine-learning techniques.

关键词： Cancer imaging computed tomography(Ct) magnetic resonance imaging(MRI) positron emission tomography(PEt) cross-sectional imaging

the effects of gonadal hormones on learning and memory in male mammals： A review

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Current Zoology 2011年第4期57卷 543-558页

作者： Stuart t. LEONARD peter J. WINSAUER Department of Pharmacology and Experimental therapeutics Louisiana State University Health Sciences Center 1901 Perdido Street New Orleans LA 70112-1393

the primary role of the gonadal steroid hormones in mammals is to regulate reproduction and related behaviors; however, both androgens and estrogens are also integrally involved in mediating higher brain function and processes including cognition, neural development, and neural plasticity. In particular, a number of studies show that estradiol modulates dendritic spine growth and synapse density （synaptic plasticity） in the hippocampus of females, and that increased estradiol levels are generally associated with improvements on a variety of learning and memory tasks. While the majority of research has focused on the beneficial effects of estradiol in females, much less attention has been given to testosterone and its effects on learning and memory in males. Similar to estradiol titers in females, testosterone titers in males decline with age, albeit more gradually, and this decline has been correlated with impairment of certain cognitive tasks. Moreover, studies involving both humans and animals indicate that testosterone and its metabolites can augment responding on certain behavioral tasks, depending on the subject＇s current hormonal state, the response required, and the stimuli involved （e.g., those involving spatial or nonspatial stimuli）. While the exact mechanisms by which testosterone exerts its effects on learning and memory are not fully understood, recent findings suggest that testosterone modulates learning and memory in males through an interaction with the cholinergic system. the overall objective of this review is to discuss studies investigating the role of the gonadal hormones in mediating learning and memory processes in male mammals [Current Zoology 57 （4）： 543-558, 2011].

关键词： testosterone Learning and memory Cholinergic system Mammals Cognition Androgens

Novel ecosystems created by coal mines in central Queensland’s Bowen Basin

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Ecological Processes 2013年第1期2卷 368-379页

作者： peter D Erskine Andrew t Fletcher Centre for Mined Land Rehabilitation The University of QueenslandBrisbane QLD 4072Australia

Introduction:Open-cut coal mining began in central Queensland’s Bowen Basin approximately 50 years *** this period of time,mine rehabilitators have used a variety of tree,shrub,and groundcover species to create‘novel ecosystems’to stabilise soils and provide vegetative cover for pre-supposed final end-land *** examine post-mining rehabilitation from multiple soil and vegetation monitoring activities in the Bowen Basin to assess the similarity of landforms,plant composition,and trends in plant diversity compared to unmined reference ***:Rehabilitated spoil dumps and reference sites were assessed using soil and vegetation data contained in compliance monitoring reports from Goonyella Riverside,Moura,Oaky Creek,Rolleston,and Blackwater ***,soil chemistry,and plant species mixes of rehabilitation aged from 2 to 22 years were compared to selected reference ***:Mines in this region have generally proposed one of two post-rehabilitation end-land uses:either pasture for cattle grazing or reconstructed native communities which potentially provide native fauna *** data from a selection of these mine sites suggest that when their rehabilitation was compared to nearby reference sites median slope values were between 2.5 and 7 times steeper and soil pH,electrical conductivity,and phosphorus levels were significantly *** steeply sloped landforms,poor soil characteristics,depauperate native species pool,and uniform presence of exotic pasture grasses in the rehabilitation indicate that most of these newly created ecosystems should not be used for cattle grazing and also have few natural ***:Legislative and community expectations have changed progressively over time and,although much of the rehabilitation is currently dominated by an assemblage of exotic buffel grass(Cenchrus ciliaris)and Acacia spp.,recent environmental authorities suggest these‘novel ecosystems’will be judged against native refere

关键词： Coal mining Completion criteria Environmental conditions Novel ecosystems

Molecular simulation study of dynamical properties of room temperature ionic liquids with carbon pieces

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Science China Chemistry 2016年第5期59卷 594-600页

作者： Guang Feng Wei Zhao peter t.Cummings Song Li State Key Laboratory of Coal Combustion School of Energy and Power Engineering Huazhong University of Science and Technology Department of Chemical and Biomolecular Engineering Vanderbilt University

Room temperature ionic liquids(RtILs) with dispersed carbon pieces exhibit distinctive physiochemical properties. to explore the molecular mechanism, RtILs/carbon pieces mixture was investigated by molecular dynamics(MD) simulation in this work. Rigid and flexible carbon pieces in the form of graphene with different thicknesses and carbon nanotubes in different sizes were dispersed in a representative RtIL 1-butyl-3-methyl-imidazolium dicyanamide([Bmim][DCA]). this study demonstrated that the diffusion coefficients of RtILs in the presence of flexible carbons are similar to those of bulk RtILs at varying temperatures, which is in contrast to the decreased diffusion of RtILs in the presence of rigid carbons. In addition, interfacial ion number density at rigid carbon surfaces was higher than that at flexible ones, which is correlated with the accessible external surface area of carbon pieces. the life time of cation-anion pair in the presence of carbon pieces also exhibited a dependence on carbon flexibility. RtILs with dispersed rigid carbon pieces showed longer ion pair life time than those with flexible ones, in consistence with the observation in diffusion coefficients. this work highlights the necessity of including the carbon flexibility when performing MD simulation of RtILs in the presence of dispersed carbon pieces in order to obtain the reliable dynamical and interfacial structural properties.

关键词： room temperature ionic liquids carbon pieces flexibility dynamical property ion pair stability interfacial structure

Heat shock protein 47 promotes tumor survival and therapy resistance by modulating AKt signaling via PHLPP1 in colorectal cancer

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Cancer Biology & Medicine 2020年第2期17卷 343-356页

作者： Yijye Chern peter Zhang Hyelim Ju Isabella t.tai Division of Gastroenterology Department of MedicineUniversity of British ColumbiaVancouver V6T 1Z4Canada Michael Smith Genome Sciences Center British Columbia Cancer AgencyVancouver V5Z 4S6Canada

Objective:Heat shock protein 47(HSP47)is a collagen-specific molecular chaperone that facilitates collagen *** role in cancer remains largely *** this study,we investigated the roles o f HSP47 in colorectal cancer(CRC)and therapy ***:Expression o f HSP47 in CRC tissues was examined(1)in paired human CRC/adjacent normal tissues,using real time quantitative reverse transcription polymerase chain reaction(qRt-PCR),the Cancer Genome Atlas(tCGA)database,and 22 independent m icroarray databases(curated CRC).In vitro studies on several CRC cell lines(H C t 116,RKO and C C L228)with modulated HSP47 expression were conducted to assess cell viability and apoptosis(tU N EL assay and caspase-3/-7)during exposure to *** signaling and co-imm unoprecipitation studies were performed to examine HSP47 and PHLPP1 *** vivo studies using tumor xenografts were conducted to assess the effects of HSP47 modulation on tum or growth and therapy ***:HSP47 was upregulated in CRC and was associated with poor prognosis in individuals with *** vitro,HSP47 overexpression supported the survival of CRC cells,whereas its knockdown sensitized cells to 5-fluorouracil(5-FU).HSP47 promoted survival by inhibiting apoptosis,enhancing AKt phosphorylation,and decreasing expression of the AKt-specific phosphatase PHLPP1 when cells were exposed to *** effects were partly results of the interaction between HSP47 and PHLPP1,which decreased PHLPP1 stability and led to more persistent AKt *** vivoy HSP47 supported tumor growth despite 5-FU ***:HSP47 supports the growth of CRC tumors and suppresses the efficacy of chemotherapy via modulation of AKt signaling.

关键词： HSP47 AKt PHLPP1 colorectal cancer resistance

Composite recommendations： from items to packages

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Frontiers of Computer Science 2012年第3期6卷 264-277页

作者： Min XIE Laks V. S. LAKSHMANAN peter t. WOOD Department of Computer Science University of British Columbia Vancouver V6T 1Z4 Canada Department of Computer Science and Information Systems Birkbeck University of London London WCIE 7HX UK

Classical recommender systems provide users with a list of recommendations where each recommendation consists of a single item, e.g., a book or DVD. However, sev- eral applications can benefit from a system capable of recom- mending packages of items, in the form of sets. Sample appli- cations include travel planning with a limited budget （price or time） and twitter users wanting to select worthwhile tweeters to follow, given that they can deal with only a bounded num- ber of tweets. In these contexts, there is a need for a system that can recommend the top-k packages for the user to choose from. Motivated by these applications, we consider composite recommendations, where each recommendation comprises a set of items. Each item has both a value （rating） and a cost associated with it, and the user specifies a maximum total cost （budget） for any recommended set of items. Our composite recommender system has access to one or more component recommender systems focusing on different do- mains, as well as to information sources which can provide the cost associated with each item. Because the problem of deciding whether there is a recommendation （package） whose cost is under a given budget and whose value exceeds some threshold is NP-complete, we devise several approximation algorithms for generating the top-k packages as recommen- dations. We analyze the efficiency as well as approximation quality of these algorithms. Finally, using two real and two synthetic datasets, we subject our algorithms to thorough ex- perimentation and empirical analysis. Our findings attest tothe efficiency and quality of our approximation algorithms for the top-k packages compared to exact algorithms.

关键词： recommendation algorithms optimization,top-k query processing

Person-centered endoscopy safety checklist: development,implementation,and evaluation

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World Journal of Gastroenterology 2017年第48期23卷 8605-8614页

作者： Hanna Dubois peter t Schmidt Johan Creutzfeldt Mia Bergenmar Center for Digestive Diseases Karolinska University Hospital Center for Advanced Medical Simulation and training Karolinska University Hospital Department of Medicine Karolinska Institutet Department of Perioperative Medicine and Intensive Care Karolinska University Hospital Department of Clinical Science Intervention and Technology(CLINTEC)Karolinska Institutet Department of Oncology-Pathology Karolinska Institutet

AIM to describe the development and implementation of a person-centered endoscopy safety checklist and to evaluate the effects of a "checklist intervention".MEtHODS the checklist,based on previously published safety checklists,was developed and locally adapted,taking patient safety aspects into consideration and using a person-centered approach. this novel checklist was introduced to the staff of an endoscopy unit at a Stockholm University Hospital during half-day seminars and team training sessions. Structured observations of the endoscopy team's performance were conducted before and after the introduction of the checklist. In addition,questionnaires focusing on patient participation,collaboration climate,and patient safety issues were collected from patients and staff. RESULtS A person-centered safety checklist was developed and introduced by a multi-professional group in the endoscopy unit. A statistically significant increase in accurate patient identity verification by the physicians was noted(from 0% at baseline to 87% after 10 mo,P t baseline vs 96% after 10 mo,P = nonsignificant). Observations indicated that the professional staff made frequent attempts to use the checklist,but compliance was suboptimal: All items in the observed nurse-led "summaries" were included in 56% of these interactions,and physicians participated by directly facing the patient in 50% of the interactions. On the questionnaires administered to the staff,items regarding collaboration and the importance of patient participation were rated more highly after the introduction of the checklist,but this did not result in statistical significance(P = 0.07/P = 0.08). the patients rated almost all items as very high both before and after the introduction of the checklist;hence,no statistical difference was *** the intervention led to increased patient identity verification by physicians-a patient safety improvement. Clear evidence of enha

关键词： Checklist Communication Endoscopy Observation Patient-centered care Person-centered care Patient safety teamwork