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Niche overlap in allotopic and syntopic populations of sexually interacting ground-hopper species

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Insect Science 2012年第3期19卷 391-402页

作者： Axel Hochkirch julia Groning Department of Biogeography Trier University Trier University of Osnabruck Department of Biologyl Chemistry Division of Ecology Osnabrock Germany

There is accumulating evidence that sexual interactions among species （reproductive interference） could have dramatic effects for species＇ coexistence. It has been shown that the fitness of individuals can be substantially reduced as a consequence of reproductive interference. This might subsequently lead to displacement of a species （sexual exclusion）. On the other hand, some evolutionary and ecological mechanisms might enable species to coexist, such as the divergence of mate recognition systems （reproductive character displacement）, habitat partitioning, clumped dispersion patterns or different colonization capabilities. We have previously shown that the two ground-hopper species Tetrix subulata and Tetrix ceperoi interact sexually in the laboratory as well as in the field. At sites where both species co-occur niche overlap was high, suggesting that coexistence is maintained by different niche breadths rather than by habitat partitioning. To test the hypothesis that habitat partitioning does not contribute to species＇ coexistence, we examined whether allotopic and syntopic populations of these two species differ in niche overlap （competitive release）, Our results show that niche overlap is higher in syntopic than in allotopic populations, suggesting that the site-specific habitat structure （heterogeneity） has a stronger influence on microhabitat utilization than the presence of heterospecifics. Hence, our data do not support the hypothesis that habitat partitioning plays a substantial role for the coexistence of these sexually interacting species.

关键词： coexistence competition niche breadth niche partitioning reproductive interference

Axonal protein synthesis in central nervous system regeneration:is building an axon a local matter?

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Neural Regeneration Research 2022年第5期17卷 987-988页

作者： julia Schaeffer Stephane Belin UniversitéGrenoble Alpes InsermU1216Grenoble Institut NeurosciencesGrenobleFrance

Neurons of the mature central nervous system(CNS,mainly the brain and spinal cord)are unable to regenerate spontaneously after a lesion,in contrast to neurons of the peripheral nervous system(PNS).While the extraneuronal environment was long thought to be limiting,evidence was given less than 15 years ago that neurons themselves are critical players of their own regeneration(Park et al.,2008).Indeed,CNS neurons show a decline of axon growth capacity as they mature and after an ***,the role of axonal translation is actively explored in the paradigm of embryonic neuronal growth and in peripheral nerve injury and regeneration,but less is known about the role of local protein synthesis in regrowth of adult CNS *** we discuss how the current understanding of axonal translation in the CNS may contribute to the development of novel strategies to enhance axon regeneration in the injured CNS.

关键词： synthesis system local

Novel phenotype of mouse spermatozoa following deletion of nine β-defensin genes

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Asian Journal of Andrology 2015年第5期17卷 716-719,I0005-I0006页

作者： julia R Dorin Formerly at MRC Human Genetics Unit IGMM University of Edinburgh now at MRC Centre for Inflammation Research University of Edinburgh Queen's MedicalResearch Institute 47 Little France Crescent Edinburgh EH16 4TJ Scotland UK

β-defensin peptides are a large family of antimicrobial peptides. Although they kill microbes in vitroand interact with immune cells, the precise role of these genes in vivo remains uncertain. Despite their inducible presence at mucosal surfaces, their main site of expression is the epididymis. Recent evidence suggests that a major function of these peptides is in sperm maturation. In addition to previous work suggesting this, work at the MRC Human Genetics Unit, Edinburgh, has shown that homozygous deletion of a cluster of nine β-defensin genes in the mouse results in profound male sterility. The spermatozoa derived from the mutants had reduced motility and increased fragility. Epididymal spermatozoa isolated from the cauda region of the homozygous mutants demonstrated precocious capacitation and increased spontaneous acrosome reactions compared with those from wild-types. Despite this, these mutant spermatozoa had reduced ability to bind to the zona pellucida of oocytes. Ultrastructural examination revealed a disintegration of the microtubule structure of mutant-derived spermatozoa isolated from the epididymal cauda region, but not from the caput. Consistent with premature acrosome reaction and hyperactivation, spermatozoa from mutant animals had significantly increased intracellular calcium content. This work demonstrates that in vivo β-defensins are essential for successful sperm maturation, and that their disruption alters intracellular calcium levels, which most likely leads to premature activation and spontaneous acrosome reactions that result in hyperactivation and loss of microtubule structure of the axoneme. Determining which of the nine genes are responsible for the phenotype and the relevance to human sperm function is important for future work on male infertility.

关键词： acrosome reaction antimicrobial capacitation epididymis sperm β-defensins

Treatment and prevention of epilepsy in onchocerciasis-endemic areas is urgently needed

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Infectious Diseases of Poverty 2024年第1期13卷 85-89页

作者： Robert Colebunders Joseph Nelson Siewe Fodjo Olivia Kamoen Luis-Jorge Amaral Amber Hadermann Chiara Trevisan Mark J.Taylor julia Gauglitz Achim Hoerauf Yasuaki Sato Katja Polman Maria-Gloria Basanez Dan Bhwana Thomson Lakwo Gasim Abd-Elfarag Sebastien D.Pion Global Health Institute University of AntwerpAntwerpBelgium Department of Neurology Heilig Hart ZiekenhuisLierBelgium Department of Public Health Institute of Tropical MedicineAntwerpBelgium Liverpool School of Tropical Medicine LiverpoolUK Department of Computer Science University of AntwerpAntwerpBelgium Institute of Medical Microbiology Immunology and ParasitologyUniversity Hospital BonnBonnGermany German Center for Infection Research(DZIF) Partner Site Bonn-CologneBonnGermany School of Global Humanities and Social Sciences Nagasaki UniversityNagasakiJapan MRC Centre for Global Infectious Disease Analysis and London Centre for Neglected TropicalDisease Research Department of Infectious Disease EpidemiologySchool of Public HealthImperial College LondonLondonUK National Institute for Medical Research TangaTanzania Vector Control Division Ministry of HealthKampalaUganda School of Public Health University of JubaJubaSouth Sudan Access for Humanity JubaSouth Sudan French National Research Institute for Sustainable Development MontpellierFrance

Background There is increasing epidemiological evidence supporting the association between onchocerciasis and seizures, reinforcing the concept of onchocerciasis-associated epilepsy (OAE). The aim of this paper is to provide an update on the new knowledge about OAE and to propose recommendations to the World Health Organization how to address this public health *** text During the 2nd International Workshop on OAE held on 19-21 September, 2023, in Antwerp, Belgium, participants recognised OAE as a substantial yet neglected public health problem, particularly in areas of sub-Saharan Africa where onchocerciasis remains hyperendemic. Evidence from prospective population-based studies suggest that strengthening onchocerciasis elimination efforts leads to a significant reduction of OAE incidence. There is a need to validate an OAE case definition to estimate the burden of disease and identify onchocerciasis-endemic areas requiring intensification of onchocerciasis elimination programmes and integration of epilepsy care. It is expected that raising awareness about OAE will boost the population uptake of ivermectin. The implementation of a community-based epilepsy treatment programme offering free anti-seizure medications (ASMs) has shown high effectiveness in reducing the frequency of seizures and improving the overall quality of life of people with *** To reduce OAE burden, enhanced collaboration between onchocerciasis and mental health programmes at community, national, and international levels is required. Urgent efforts are needed to ensure the uninterrupted provision of free ASMs in onchocerciasis-endemic areas. Furthermore, OAE should be included in the quantification of the onchocerciasis disease burden.

关键词： Onchocerciasis Morbidity Burden of disease Prevention Ivermectin Epilepsy Nodding syndrome Treatment Children Policy

Double aortic arch and nasogastric tubes: A fatal combination

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World Journal of Gastroenterology 2008年第16期14卷 2590-2592页

作者： julia Massaad Kelly Crawford Emory University School of Medicine Division of Digestive Diseases

Double aortic arch is a common form of complete vascular ring that encircles both the trachea and the esophagus, and presents with various respiratory and esophageal symptoms, usually in the pediatric population. We present a case of double aortic arch in an adult patient that manifested as massive upper gastrointestinal bleeding after prolonged nasogastric intubation.

关键词： Nasogastric tubes Aortoesophageal fistula Gastrointestinal bleeding Double aortic arch Vasculardngs

Probiotics and prebiotics in chronic inflammatory bowel diseases

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World Journal of Gastroenterology 2006年第37期12卷 5941-5950页

作者： julia B Ewaschuk Levinus A Dieleman Centre of Excellence for Gastrointestinal Inflammation and Immunity Research Uni-versity of Alberta Edmonton Alberta Canada

The prokaryotic and eukaryotic cells of the colon exist in a highly complex, but harmonious relationship. Disturbances in this remarkable symbiosis can result in the development of inflammatory bowel diseases (IBD). Although the etiology of IBD is not entirely understood, it is known that the chronic inflammation of Crohn’s disease, ulcerative colitis and chronic pouchitis are a result of an overly aggressive immune response to the commensal intestinal flora in genetically susceptible hosts. Recent studies have enhanced our ability to understand the interaction between the host and its intestinal microflora and the role the microflora plays in maintaining intestinal homeostasis. As we begin to understand the benefi ts conferred to the intestine by the microflora, the notion of modifying the composition of the bacterial load to improve human health has arisen. A signifi cant body of research now exists investigating the role of probiotics and prebiotics in ameliorating chronic intestinal inflammation. This article will begin with an overview of the role of the commensal microflora in maintaining mucosal immune homeostasis, and how a dysregulated immune response to the intestinal microflora results in IBD. This will be followed by a summary of the use of probiotics and prebiotics in experimental and human IBD.

关键词： Colitis Crohn's disease Microflora Immunity Probiotics Prebiotics

Soil respiration in paludified forests of European Russia

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Journal of Forestry Research 2020年第5期31卷 1939-1948页

作者： Dmitry Ivanov Fedor Tatarinov julia Kurbatova A.N.Severtsov Institute of Ecology and Evolution RAS Leninsky Prospekt 33MoscowRussia 119071 Weizmann Institute of Science Herzl St 23476100 RehovotIsrael

Soil respiration studies in paludified forests of the European part of Russia are quite rare in comparison with those of open peat bogs,which make long-term observations in this region highly *** this study,soil CO2 emissions were measured by the close chamber method in different microlandscapes of paludified *** four summer seasons with different environments,soil respiration ranged from 1078 to 248 mg CO2 m^-2 h^-1 in a paludified spruce forest site with coarse woody debris to 659–820 mg CO2 m^-2 h^-1 in a paludified boggy pine *** most intensive soil respiration was observed during the hot summer of 2013 and the lowest in the hot and humid summer of *** total soil CO2 emissions in paludified forests in 2015–2016 were approximately 2000–3000 g CO2 *** the year,the lowest CO2 emission values were observed from November to April(14–84 mg CO2 m^-2 h^-1)and the maximum were in July and August(522–1205 mg CO2 m^-2 h^-1).The contributions of CO2 emissions in the cold November–April period were 6–8.5%.The impacts of temperature on soil respiration were higher(r2=0.45–0.57)than those of groundwater levels(r^2=0.17–0.49).Soil respiration in the paludified spruce forest and in the pine bog generally were higher than emissions from ecosystems with similar hydrothermal conditions in the boreal zone.

关键词： Carbon flux Chamber measurements CO2 emission Peatlands Southern taiga

Investigating approaches to improving rendering performance of 3D city models on mobile devices

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Geo-Spatial Information Science 2014年第2期17卷 73-84页

作者： Claire ELLUL julia ALTENBUCHNER Department of Civil Environmental and Geomatic EngineeringUniversity College LondonLondonUK

Three-dimensional(3D)city models have uses including on-site validation of utility infrastructure,support for augmented reality,personalized tourist information,real estate sales,and 3D pedestrian ***,such applications are deployed on mobile devices,whose use is becoming more *** devices are used for more professional use requiring larger screens,mobile phones for more casual ***,many 3D city models contain hundreds of buildings,which in turn results in performance issues when attempting to visualize such models on these *** issues can be identified as contributory factors-the lower specification of the mobile device itself when compared with desktop machines and the lower bandwidth network between the device and the server(3G mobile or Wi-Fi).Both of these can be addressed by reducing the volume of data in the *** achieve this,we generalize a 2D data-set(using aggregation and simplification)and then extrude the generalized 2D maps to *** minimizes the number of buildings to be transmitted over the network and processed by the on-board graphics *** additionally address the bandwidth issue,we make use of topological data structuring to build and transmit a minimal description for each *** these approaches,we compare the results obtained for generalized and un-generalized data-sets,on a tablet and mobile device.A performance increase of between 7 and 9 times is observed.

关键词： 3D GIS generalization openGL ES mobile devices performance

Default polyfunctional T helper 1 response to ample signal 1 alone

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Cellular & Molecular Immunology 2021年第7期18卷 1809-1822页

作者： Luca Danelli Georgina Cornish julia Merkenschlager George Kassiotis Present address:Laboratory of Molecular Immunology The Rockefeller UniversityNew YorkNY10065USA Department of Medicine Faculty of MedicineImperial College LondonLondonW21PGUK Retroviral Immunology The Francis Crick Institute1 Midland RoadLondonNW11ATUK

CD4^(+)T cells integrate well-defined signals from the T-cell receptor(TCR)(signal 1)and a host of costimulatory molecules(signal 2)to initiate clonal expansion and differentiation into diverse functional T helper(Th)***,our ability to guide the expansion of context-appropriate Th subsets by deploying these signals in vaccination remains *** cell-based vaccines,we selectively amplified signal 1 by exclusive presentation of an optimized peptide:MHC II(pMHC II)complex in the absence of classic *** to expectations,amplified signal 1 alone was strongly immunogenic and selectively expanded highaffinity TCR clonotypes,despite delivering intense TCR *** contrast to natural infection or standard vaccines,amplified signal 1,presented by a variety of professional and nonprofessional antigen-presenting cells(APCs),induced exclusively polyfunctional Th1 effector and memory cells,which protected against retroviral infection and tumor challenge,and expanded tumor-reactive CD4^(+)T cells otherwise rendered unresponsive in tumor-bearing ***,our findings uncover a default Th1 response to ample signal 1 and offer a means to selectively prime such protective responses by vaccination.

关键词： CD4 T cell priming T helper differentiation peptide-MHC II complex