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Conspecific negative density dependence in American beech

Forest Ecosystems 2017年第3期4卷 174-181页

作者： Benjamin S.Ramage isabel J.Mangana Biology Department Randolph-Macon College

Background： One of the most important drivers of forest biodiversity is conspecific negative density dependence（CNDD）, a reduction in performance when conspecific densities are high. While the majority of CNDD research has focused on tropical forests, evidence is mounting that CNDD may also play an important role in temperate *** further explore the potential reach of this phenomenon, we investigated CNDD in American beech（Fagus grandifolia）in a mature mid-Atlantic ***： We used bivariate point pattern analyses to examine spatial relationships between large beech trees and conspecific saplings, and we also contrasted these patterns with comparable patterns for heterospecifics. In addition, to address the possibility of dispersal limitation and the associated effects on spatial patterns, we analyzed seedling density as a function of adult conspecific ***： We found that beech saplings were more repel ed from large conspecifics than large heterospecifics, despite the fact that beech seedling density was positively correlated with beech basal area. However, saplings of other canopy tree species were also repel ed from adult beech trees, suggesting a general suppressive effect. Nonetheless, the discrepancy between beech seedling and sapling densities beneath adult conspecifics suggests that beech seedling survival rates were reduced in vicinity of conspecific ***： Regardless of the extent to which beech inhibits heterospecific trees, a negative effect on conspecific recruits may be critical for biodiversity maintenance. Without this conspecific suppression, a dense layer of shade-tolerant beech saplings could form beneath adult beech trees. If this were to occur, beech would have a substantial head-start fol owing canopy disturbance, and this late-successional species could potential y dominate a stand in perpetuity,through repeated disturbance cycles.

关键词： Biodiversity Disturbance Dispersal limitation Diversity Fagus grondifolia Janzen-Connell effects Mid-Atlantic Point pattern analysis Regeneration Temperate forest

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Nuptial gifts and female fecundity in the neotropical katydid Conocephalus ictus （Orthoptera： Tettigonidae）

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Insect Science 2015年第1期22卷 106-110页

作者： isabel Ortiz-Jimenez Raul Cueva del Castillo Laboratorio de Ecologia UBIPRO UNAM FES Iztacala M6xico Edo. Mexico M6xico

In general, female fitness is greatly increased in gift-giving insects. In katydids, this nuptial gift consists of a gelatinous mass produced by accessory glands： the spermato- phylax, which is attached to the ampulla. During mating, males of the neotropical katydid Conocephalus ictus transfer a spermatophylax that is ingested by the females. Fecundity, egg-laying rate and longevity were higher in females that consumed the spermatophylax than in those that did not. Also, female receptivity turned off after mating. Females actively rejected other males by hitting them with their forelegs and moving away. Their refractory period lasted as long as 17 d. Only a few females accepted a 2nd mating and died a few days later. In C. ictus, spermatophylax consumption can be beneficial for both males and females. On one hand, the compounds in the spermatophylax or the ejaculate could prevent or delay females from copulating with rivals, thus avoiding sperm competition. On the other hand, such compounds can improve the females＇ opportunity to increase their lifespan and fecundity. Moreover, a rise in egg-laying rate may lower the risk of female prereproductive death caused by rapid oviposition. In any case, the boost in female egg laying might also be beneficial for males because their number of offspring increases.

关键词： female fitness katydid neotropic spermatophylax

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Effects of a sex ratio gradient on female mate-copying and choosiness in Drosophila melanogaster

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Current Zoology 2018年第2期64卷 251-258页

作者： Magdalena MONIER Sabine NOBEL Guillaume isabel Etienne DANCHIN UMR-5174 Laboratoire Evolution & Diversite Biologique (EDB) Centre National de la Recherche Scientifique (CNRS) Institut de Recherche pour le Developpement (IRD) Universite de Toulouse 118 route de NarbonneF-31062 Toulouse Cedex 9 France Centre de Recherches sur la Cognition Animale (CRCA) Centre de Biologie Integrative (CBI) Centre National de la Recherche Scientifique (CNRS) Universite de Toulouse 118 route de Narbonne F-31082 Toulouse Cedex 9 France

In many sexually reproducing species, individuals can gather information about potential mates by observing their mating success. This behavioral pattern, that we call mate-copying, was reported in the fruit fly Drosophila rnelanogaster where females choosing between 2 males of contrasting phenotypes can build a preference for males of the phenotype they previously saw being chosen by a demonstrator female. As sex ratio is known to affect mate choice, our goal was to test whether mate-copying is also affected by encountered sex ratios. Thus, we created a gradient of sex ratio during demonstrations of mate-copying experiments by changing the number of females observ- ing from a central arena 6 simultaneous demonstrations unfolding in 6 peripheral compartments of a hexagonal device. We also tested whether the sex ratio experienced by females during demon- strations affected their choosiness （male courtship duration and double courtship rate） in subse- quent mate-choice tests. Experimental male：female sex ratio during demonstrations did not affect mate-copying indices, but positively affected the proportion of both males courting the female during mate-choice tests, as well as male courtship duration, the latter potentially explaining the for- mer relationship. As expected, the sex ratio affected female choosiness positively, and Drosophila females seem to have evolved a mate-copying ability independently of sex ratio, and a capacity to adapt their choosiness to male availability. This suggests that, as in many animal species, individuals, especially females, can adapt their mate choice depending on the current sex ratio.

关键词： competition Drosophila melanogaster experimental protocol mate-copying social learning sex ratio.

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Optimizing strategies to reduce alcohol consumption and relapses,improving abstinence in liver transplant recipients

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Hepatobiliary Surgery and Nutrition 2022年第1期11卷 153-155页

作者： isabel Legaz Manuel Muro Department of Legal and Forensic Medicine Biomedical Research Institute(IMIB)Regional Campus of International Excellence“Campus Mare Nostrum”Faculty of MedicineUniversity of MurciaMurciaSpain Immunology Service Instituto Murciano de Investigación Biosanitaria(IMIB)Hospital Clínico Universitario Virgen de la Arrixaca(HCUVA)MurciaSpain

We have read with great attention and special interest the paper by Carrique and collaborators entitled:Results of Early Transplantation for Alcohol-Related Cirrhosis:Integrated Addiction Treatment with Low Rate of Relapse(1).In this prospective study,the authors initiated a pilot program to challenge the paradigm of the“6-month rule”of abstinence for patients with alcohol-related liver disease(ALD)requiring a transplant(2).

关键词： alcohol liver initiated

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Developments and characteristics of craft beer production processes

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Food Bioscience 2022年第1期45卷 232-248页

作者： Salvador Villacreces Carlos A.Blanco isabel Caballero Dpto de Ingeniería Agrícola Forestal ETS de Ingenierías AgrariasUniversidad de Valladolid34004Palencia.Spain

Beer is a popular drink and represents the most widely consumed alcoholic beverage in the *** recent years,there has been a significant growth of independent craft breweries,even in countries without a brewing tradition.A craft brewery is usually defined as a small,independent and traditional ***,consumers are looking for genuine,singular,different and high-quality *** beer manufacturers have responded to this with the introduction of a novel combination of raw or malted cereals and have modified the beer flavours and taste with the addition of fruit,spices,*** work presents an analysis of the different aspects related to craft *** characteristics and brewing singularities are *** quality and safety standards used are examined and future trends of craft beer are also discussed.

关键词： Craft beer Ingredients Craft beer quality By-products Microbiological safety

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Early-onset colorectal cancer:A review of current knowledge

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World Journal of Gastroenterology 2023年第8期29卷 1289-1303页

作者： Margarida R Saraiva Isadora Rosa isabel Claro Department of Gastroenterology Instituto Português de Oncologia de Lisboa Francisco GentilLisboa 1099-023Portugal

Colorectal cancer(CRC)is one of the most prevalent malignancies *** most prevalent among older people,its incidence above 50 years old has been decreasing globally in the last decades,probably as a result of better ***,its incidence in patients below 50 years old[early-onset CRC(EO-CRC)]has been increasing,for reasons not yet fully ***’s increasing incidence is genre independent but shows racial disparities and has been described to occur *** follows a birth-cohort effect which probably reflects a change in exposure to CRC risk *** incidence is predicted to double until 2030,which makes EO-CRC a serious public health *** modifiable and non-modifiable risk factors have been identified-some are potential targets for preventive ***-CRC is often diagnosed at advanced stages and histological features associated with poor prognosis have been ***-CRC presents some distinctive features:Microsatellite instability is common,but another subtype of tumours,both microsatellite and chromosome stable also seems *** are no age-specific treatment protocols and studies on EO-CRC survival rates have shown conflicting *** to the higher germline pathological mutations found in EO-CRC patients,an accurate genetic risk evaluation should be *** this review,we summarize the current evidence on epidemiological,clinical,histopathological and molecular features of EO-CRC and discuss the contribution of genetics and lifestyle risk *** further comment on screening strategies and specific dimensions to consider when dealing with a younger cancer patient.

关键词： Colorectal cancer Early-onset Adenocarcinoma Hereditary Birth-cohort effect Risk factors

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Intraspecific competition in Zabrotes subfasciatus： Physiological and behavioral adaptations to different amounts of host

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Insect Science 2012年第1期19卷 102-111页

作者： isabel R.V.Teixeira Fernando S.Zucoloto Insect Nutrition and Feeding Behavior Laboratory Department of BiologyFaculdade de Filosofia Ciencias e Letras de Ribeirao Preto Universidade de Sao PauloSao Paulo epartment of Biology Federal Institute of Sul de Minas-Campus MuzambinhoIFSULDEMINAS MuzambinhoMinas GeraisBrazil

The effects of competition on populations of the bean weevil Zabrotes sub- fasciatus were analyzed during 41 generations under different competition levels. Three competition environments were established by maintaining the number of couples （6） and varying the amount of available host seeds： HC, high （limited availability of host： 1.35 g）; IC, intermediate （intermediate availability of host： 6 g）; and LC, low competition （abun- dance of host： 36 g）. It was found that the distribution of the eggs laid on grains was different among treatments： in LC, for example, although females showed high fecundity （35.4 ± 5.6 eggs/female） the number of eggs laid on each grain was small （1.2 ± 0.4 eggs on each seed）, thus avoiding larval competition of their offspring; whereas in HC treatment, females showed low fecundity （27.04 ± 4.5 eggs/female） but laid many eggs on each grain （15.03 ± 4.3 eggs）. There were no changes in the ability to respond to different amounts of host via oviposition behavior （egg distribution） during 41 generations. How- ever, HC females had more offspring than LC females under HC conditions. This suggests that HC insects evolved toward higher fitness in crowded conditions. In addition, after inverting the competition level, insects behaved independently of the treatment conditions they experienced through generations, thus showing that oviposition behavior is flexible. Taken together, our results show that Z. subfasciatus presents a broad range of behavioral and physiological responses which allows for quick and reversible adjustments to sudden changes in the amount of resources.

关键词： bean weevil Coleoptera egg distribution oviposition Phaseolus vulgaris phenotypic plasticity

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Sentinel lymph node metastasis after neoadjuvant treatment in breast cancer:Any size matters?

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World Journal of Clinical Oncology 2015年第6期6卷 202-206页

作者： isabel T Rubio Breast Surgical Oncology Unit Breast Cancer CenterHospital Universitario Vall d'HebronUniversitat Autònoma de Barcelona

One of the advantages of neoadjuvant chemotherapy(NAC) treatments is its ability to convert patients who need a mastectomy in breast conservative surgery. NAC has also increased the conversion of node positive patients into node negative in around 40% allowing the use of sentinel node biopsy(SLN) in this setting. Timing of SLN biopsy after NAC has been a subject of debate. In patients with clinically node negative before NAC,rates of success and false negative rates of SLN after NAC are similar to those in the adjuvant setting,so SLN after NAC in previous negative axilla has been incorporated in the staging of the axilla. More controversial is its use in patients with positive axillary nodes before NAC who convert to node negative after NAC. Several randomized studies have reported the identification rates and the false negative rates of the SLN after NAC,concordant in the importance of surgical technique. As there is an agreement in the abandon of the immunohistochemistry(IHC) for SLN in the adjuvant setting as SLN IHC detected metastasis appear to have no impact on overall survival,in patients with SLN after NAC the inclusion of isolated tumor cell(ITC) as positive nodes lowers the false negative rates of the technique,suggesting the importance of assessing the SLN by IHC after NAC and considering it as residual disease. Longer follow up is needed to determine the prognostic implications of ITC in the SLN after NAC.

关键词： Sentinel node Metastasis Neoadjuvant treatment Breast cancer

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Cell-type-specific memory consolidation driven by translational control

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Signal Transduction and Targeted Therapy 2021年第2期6卷 206-208页

作者： Qing Zhang isabel Bestard-Lorigados Weihong Song Townsend Family Laboratories Department of PsychiatryThe University of British ColumbiaVancouverBCCanada Institute of Aging School of Mental Health and Kangning HospitalThe Second Affiliated Hospital and Yuying Children’s HospitalWenzhou Medical UniversityWenzhouChina

***’s group has significantly contributed to the understanding of translational control in learning and *** a recent Nature article,they further reported the cell-typespecific translational control underlying memory consolidation.1 Long-term potentiation(LTP)has been widely acknowledged as one of the main cellular models of learning and ***,there are two components of LTP driven by different stimulations and *** early phase of LTP(E-LTP)and short-term memory(STM)are evoked for short periods and are temporary,relying primarily on modifications of pre-existing *** late phase of LTP(L-LTP)and consequent longterm memory(LTM)are elicited by strong and repetitive stimulation and are long-lasting,requiring new protein synthesis.

关键词： synthesis. translational stimulation

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Local Phase Portraits through the Newton Diagram of a Vector Field

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Acta Mathematica Sinica,English Series 2015年第6期31卷 1015-1034页

作者： Antonio ALGABA isabel CHECA Cristóbal GARCIA Manuel REYES Department of Mathematics Faculty of Experimental Sciences

The Newton diagram and, in particular, the lowest-degree quasi-homogeneous terms of an analytic planar vector field allow us to determine the existence of characteristic orbits and separatrices of an isolated singular point. We give an easy algorithm for obtaining the local phase portrait near the origin of a bi-dimensional differential system and we provide several examples.

关键词： Monodromy separatrices phase portraits quasi-homogeneous vector field

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