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Mate choice decisions by searchers

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Current Zoology 2013年第2期59卷 184-199页

作者： daniel d. WIEGMANN Lisa M. ANGELONI Steven M. SEUBERT J. GordonWAdE department of Biological Sciences and J. P. Scott Center for Neuroscience Mind and Behavior Bowling Green State University Bowling Green OH 43403 USA department of Biology Colorado State University Fort Collins CO 80523 USA department of Mathematics and Statistics Bowling Green State University Bowling Green OH 43403 USA

For more than two decades rudimentary versions of the fixed sample and sequential search strategies have provided the primary theoretical foundation for the study of mate choice decisions by searchers. The theory that surrounds these models has expanded markedly over this time period. In this paper, we review and extend results derived from these models, with a focus on the empirical analysis of searcher behavior. The basic models are impractical for empirical purposes because they rely on the as- sumption that searchers--and, for applied purposes, researchers--assess prospective mates based on their quality, the fitness consequences of mate choice decisions. Here we expound versions of the models that are more empirically useful, reformulated to reflect decisions based on male phenotypic characters. For some organisms, it may be possible to use preference functions to de- rive predictions from the reformulated models and thereby avoid difficulties associated with the measurement of male quality per se. But predictions derived from the two models are difficult to differentiate empirically, regardless of how the models are formu- lated. Here we develop ideas that illustrate how this goal might be accomplished. In addition, we clarify how the variability of male quality should be evaluated and we extend what is known about how this variability influences searcher behavior under each model. More general difficulties associated with the empirical study of mate choice decisions by searchers are also discussed [Current Zoology 59 （2）： 184-199, 2013].

关键词： dispersive order Fixed sample strategy Mate choice Preference functions Sequential search Stochastic dominance

Stress and immunological response of heifers divergently ranked for residual feed intake following an adrenocorticotropic hormone challenge

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Journal of Animal Science and Biotechnology 2018年第1期9卷 111-118页

作者： A.K.Kelly P.Lawrence B.Earley d.A.Kenny M.McGee School of Agriculture and Food Science College of Health and Agricultural SciencesUniversity College Dublin Livestock Systems Research department Teagasc Animal&Grassland Research and Innovation CentreGrangeDunsanyCo. Animal and Bioscience Research department Animal&Grassland Research and Innovation CentreTeagascDunsanyCo.

Background： When an animal is exposed to a stressor, metabolic rate, energy consumption and utilisation increase primarily through activation of the hypothalamic-pituitary-adrenal（HPA） axis. Changes to partitioning of energy by an animal are likely to influence the efficiency with which it is utilised. Therefore, this study aimed to determine the physiological stress response to an exogenous adrenocorticotropic hormone（ACTH） challenge in beef heifers divergently ranked on phenotypic residual feed intake（RFI）.Results： data were collected on 34 Simmental weaning beef heifers the progeny of a well characterized and divergently bred RFI suckler beef herd. Residual feed intake was determined on each animal during the postweaning stage over a 91-day feed intake measurement period during which they were individually offered adlibitum grass silage and 2 kg of concentrate per head once daily. The 12 highest [0.34 kg dM/d] and 12 lowest[-0.48 kg dM/d] ranking animals on RFI were selected for use in this study. For the physiological stress challenge heifers（mean age 605 ± 13 d; mean BW 518 ± 31.4 kg） were fitted aseptically with indwelling jugular catheters to facilitate intensive blood collection. The response of the adrenal cortex to a standardised dose of ACTH（1.98 IU/kg metabolic BW^（0.75）） was examined. Serial blood samples were analysed for plasma cortisol, ACTH and haematology variables. Heifers differing in RFI did not differ（P = 0.59） in ACTH concentrations. concentration of ACTH peaked（P 〈 0.001） in both RFI groups at 20 min post-ACTH administration, following which concentration declined to baseline levels by 150 min. Similarly, cortisol systemic profile peaked at 60 min and concentrations remained continuously elevated for 150 min. A RFI × time interaction was detected for cortisol concentrations（P = 0.06） with high RFI heifers had a greater cortisol response than Low RFI from 40 min to 150 min relative to ACTH administration. cortisol response was positively assoc

关键词： Beef cattle cortisol Feed efficiency Residual feed intake Stress response

Identification of characteristic plant co-occurrences in neotropical secondary montane forests

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Journal of Plant Ecology 2009年第1期2卷 31-41页

作者： Miguel d.Mahecha Alfredo Martı´nez Holger Lange Markus Reichstein Erwin Beck max Planck Institute for Biogeochemistry PO Box 10016407701 JenaGermany department of Environmental Sciences Swiss Federal Institute of Technology—ETH Zurich8092 ZurichSwitzerland Bayreuth Centre for Ecology and Environmental Research University of Bayreuth95440 BayreuthGermany Fundacion cordillera Tropical Jaime Roldos 4-80 y Huayna CapacEd.El Consorcio of.412CuencaEcuador Norwegian Forest and Landscape Institute PO Box 1151431 AsNorway

Aims Inferring environmental conditions from characteristic patterns of plant co-occurrences can be crucial for the development of conservation strategies concerning secondary neotropical ***,nomethodological agreement has been achieved so far regarding the identification and classification of characteristic groups of vascular plant species in the *** study examines botanical and,in particular,statistical aspects to beconsidered in such *** on these,we propose a novel data-driven approach for the identification of characteristic plantco-oc currences in neotropical secondary mountain *** Floristic inventory data were gathered in secondary tropical mountain forests in *** classification was performed by coupling locally adaptive isometric feature mapping,a non-linear ordination method and fuzzy-c-means *** approach was designed for dealing with underlying non-linearities and uncertainties in the inventory *** Findings The results indicate that the applied non-linear mapping in combination with fuzzy classification of species occurrence allows an effective identification of characteristic groups of co-occurring species as fuzzy-defined *** selected species indicated groups representing characteristic life-form distributions,as they correspond to various stages of forest *** the identified‘characteristic species groups’with meta-information derived from accompanying studies indicated that the clusters can also be related to habitat *** conclusion,we identified species groups either characteristic of different stages of forest succession after clear-cutting or of impact by fire or a *** expect that the proposed data-mining method will be useful for vegetation classification where no a priori knowledge is available.

关键词： secondary tropical mountain forests characteristic species groups non-linear ordination fuzzy-c-means clustering Ecuador

The association between body composition and self-reported co-morbidity in subjects with chronic obstructive pulmonary disease

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Open Journal of Internal Medicine 2012年第2期2卷 100-106页

作者： Erica P. A. Rutten per S. Bakke Sreekumar G. Pillai Scott Wagers Thomas B. Grydeland Amund Gulsvik Emiel F. M. Wouters Center of Expertise for Chronic Organ Failure (Ciro) Horn The Netherlands Genetics GlaxoSmithKline R&D Raleigh USA Section of Thoracic Medicine Institute of Medicine University of Bergen Bergen Norway

Background: differences in body composition are extensively investigated in subjects with coPd as low muscle mass was independently associated with increased morbidity and mortality. Also cardio-vascular co-morbidity is often reported in coPd and the contribution of fat mass in coPd related co-morbidity is gaining interest. We hypothesized that the prevalence of low muscle mass and high fat mass is higher in subjects with coPd compared to a group of current and former smokers without coPd, which result in higher reported cardiovascular co-morbidity in the coPd group. Methods: In 954 subjects with coPd and 955 subjects without coPd, body composition was assessed by bio-electrical impedance analysis and information on self-reported co-morbidity was collected. Participants were stratified for low fat free mass index and high fat mass index (resp. fat free mass index 50th percentile of the subjects without coPd). Results: Subjects with coPd were more likely to have low fat free mass index than current and former smokers without coPd. The prevalence of high fat mass index was comparable between the groups. The percentage of self-reported co-morbidity was higher in subjects with coPd, but only reports of myocardial infarction were disease specific. conclusion: Low fat free mass index was more common in coPd, but the prevalence of high fat mass index was comparable between subjects with and without coPd. Nevertheless, subjects with coPd reported more myocardial infarction, implying that other factors than the amount of fat mass are involved in the increased co-morbidity in coPd.

关键词： co-Morbidity Fat Free Mass Fat Mass

Preclinical evaluation of azathioprine plus buthionine sulfoximine in the treatment of human hepatocarcinoma and colon carcinoma

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World Journal of Gastroenterology 2011年第34期17卷 3899-3911页

作者： Borja Hernández-Breijo Jorge Monserrat Sara Ramírez-Rubio Eva P Cuevas diana Vara Inés díaz-Laviada M dolores Fernández-Moreno Irene d Román Javier P Gisbert Luis G Guijarro Molecular Hepatic Toxicology Unit Biochemistry and Molecular Biology Department University of Alcalá Networked Biomedical Research Center of Hepatic and Digestive Diseases (CIBEREHD) Medicine department University of Alcalá Neuroendocrinology of Cannabinoid/Vanilloid System Unit Biochemistry and Molecular Biology Department University of Alcalá Gastroenterology Unit Hospital de la Princesa Institute of Health Research Princesa Networked Biomedical Research Center of Hepatic and Digestive Diseases (CIBEREHD)

AIM: To evaluate the efficacy and the safety of azathioprine (AZA) and buthionine sulfoximine (BSO) bylocalized application into HepG2 tumor in ***: different hepatoma and colon carcinoma cell lines (HepG2, HuH7, Chang liver, LoVo, RKO, SW-48, SW-480) were grown in minimal essencial medium supplemented with 10% fetal bovine serum and 1% antibiotic/antimycotic solution and maintained in a humidified 37 ℃ incubator with 5% co2. These cells were pretreated with BSO for 24 h and then with AZA for different times. We examined the effects of this combination on some proteins and on cellular death. We also studied the eff icacy and the safety of AZA (6 mg/kg per day) and BSO (90 mg/kg per day) in HepG2 tumor growth in vivo using athymic mice. We measured safety by serological markers such as aminotransferases and creatine ***: The in vitro studies revealed a new mechanism of action for the AZA plus BSO combination in the cancer cells compared with other thiopurines (6-mercaptopurine, 6-methylmercaptopurine, 6-thioguanine and 6-methylthioguanine) in combination with BSO. The cytotoxic effect of AZA plus BSO in HepG2 cells resulted from necroptosis induction in a mitochondrial-dependent manner. From kinetic studies we suggest that glutathione (GSH) depletion stimulates c-Jun amino-terminal kinase and Bax translocation in HepG2 cells with subsequent deregulation of mitochondria (cytochrome c release, loss of membrane potential), and proteolysis activation leading to loss of membrane integrity, release of lactate dehydrogenase and dNA degradation. Some of this biochemical and cellular changes could be reversed by N-acetylcysteine (a GSH replenisher). In vivo studies showed that HepG2 tumor growth was inhibited when AZA was combined with ***: Our studies suggest that a combination of AZA plus BSO could be useful for localizedtreatment of hepatocellular carcinoma as in the currently used transarterial chemoembolization method.

关键词： Azathioprine Buthionine sulfoximine Transarterial chemoembolization Glutathione Apoptosis Necrosis

Research on modeling and applying system of combination object

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Journal of Harbin Institute of Technology(New Series) 2000年第S1期7卷 84-86页

作者： GONG Na, WANG Ya-fen, ZHANG Xian-kui (School of Architecture Engineering, Harbin Institute of Technology, Harbin 150001, China) (design department, Harbin Boiler co.LTd, Harbin 150001, China)

While studying descriptive Geometry & Mechanical drawing, students always feel that it is very difficult to develop space imagining ability. This paper researches the modeling and applying system of combination object with high practicality. Through dynamic displays, students can observe the outlines of combination object vividly and roundly. At the same time, they can also quickly develop their space imagining abilities. The whole system is developed on the personal computer with VC++5.0, based on 3d max, MFC and OpenGL of PC.

关键词： combination object dynamic displays VC++ MFC openGL 3d max

客运专线高性能混凝土电通量影响因素试验研究

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铁道工程学报 2008年第7期25卷 79-82页

作者：王秀芬中铁十二局集团有限公司太原030024

研究目的:试验研究各种因素对客运专线高性能混凝土抗氯离子渗透性能的影响规律,为优选混凝土配合比参数和指导施工提供依据。研究结论:电通量作为客运专线高性能混凝土耐久性的重要评价指标受到多种因素的影响:随着水胶比的增加,混凝... 详细信息

研究目的:试验研究各种因素对客运专线高性能混凝土抗氯离子渗透性能的影响规律,为优选混凝土配合比参数和指导施工提供依据。研究结论:电通量作为客运专线高性能混凝土耐久性的重要评价指标受到多种因素的影响:随着水胶比的增加,混凝土电通量逐渐增加;含气量对混凝土电通量影响不大,含气量达4.0%时混凝土电通量仍能满足耐久性要求;应严格控制混凝土用砂含泥量小于4.0%;40%的粉煤灰掺量不仅是混凝土抗压强度的拐点,也是耐久性指标的极限点;粉煤灰烧失量对混凝土早期及28 d电通量影响较大,对56 d龄期混凝土的电通量影响不太明显;对于混凝土电通量而言,外加剂有个临界掺量。

关键词：客运专线高性能混凝土电通量影响因素试验研究

Micro-sonic sensor technology enables enhanced grass height measurement by a Rising Plate Meter

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Information Processing in Agriculture 2019年第2期6卷 279-284页

作者： d.McSweeney N.E.coughlan R.N.Cuthbert P.Halton S.Ivanov Teagasc Animal&Grassland Research and Innovation CentreMooreparkFermoyCo.CorkIreland Telecommunications Software&Systems Group Waterford Institute of TechnologyWaterfordIreland Institute for Global Food Security School of Biological SciencesQueen’s University BelfastMedical Biology Centre97 Lisburn RoadBelfast BT97BLNorthern IrelandUnited Kingdom True North Technologies Unit 14Shannon Business CentreShannonCounty ClareIreland

Globally,the Rising Plate Meter(RPM)is a device used to measure compressed sward height,to enable estimation of herbage *** improved farm management practices aided by a variety of technological advances,the standard design of a RPM has remained relatively ***,however,a RPM utilising a micro-sonic sensor,with digital data capture capability via a Bluetooth communications link to a smart device application,has been ***,we assess the comparable ability of both a standard cumulative ratchet counter RPM and the micro-sonic sensor RPM,to accurately and precisely measure fixed ***,as correct allocation of grazing area requires accurate geolocation positioning,we assess the associated GPS *** micro-sonic sensor RPM was significantly more accurate for height capture than the cumulative ratchet counter ***,across all heights,the cumulative ratchet counter RPM underestimated height by 7.68±0.06mm(mean±SE).Alternatively,the micro-sonic sensor RPM overestimated height by 0.18±0.08 *** relation to a practical applications,these discrepancies can result in an under-and overestimation of dry matter yield by 13.71%and 0.32%kilograms per hectare,*** performance of the on-board GPS did not significantly differ from that of a tertiary ***,the wireless technology,integrated mapping,and decision support tools offered by the innovative micro-sonic sensor RPM provides for a highly efficacious grassland management tool.

关键词： decision support systems dry matter yield Grassland Rising plate meter Precision agriculture Wireless sensor network

Risk factors for endophthalmitis following cataract surgery-our experience at a tertiary eye care centre in India

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International Journal of Ophthalmology(English edition) 2015年第6期8卷 1184-1189页

作者： Rohit C.Khanna Vanita Pathak Ray Madhavi Latha Sandra d Cassard Annie Mathai Garudadri C Sekhar LV Prasad Eye Institute Kallam Anji Reddy Campus Wilmer Eye Institute Johns Hopkins University

AIMTo determine the risk factors for acute endophthalmitis after cataract extraction in a tertiary care centre in *** performed a nested case control study within a retrospective cohort. The surgical records of all patients with clinically diagnosed endophthalmitis within one month after cataract surgery, performed between January 2006 and december 2009, were reviewed. These were compared with randomly selected age and gender-matched controls, from patients having routine cataract surgery within ±1wk of the endophthalmitis case. Univariable and multivariable analysis were performed to identify risk factors for *** the total 33 856 cataract surgeries performed during this period, there were 57 cases of postoperative acute endophthalmitis that met our study criteria. Thus, the overall incidence of endophthalmitis in our cohort was 1.6 per 1000 cataract extractions performed. Mean age of cases was 55.9y (Sd: 10.9y) and for controls was 55.6y (Sd: 9.8y). Thirty-five cases (61.4%) and 133 controls (59.6%) were males. Median time of onset of endophthalmitis was 4d (IQR 2-9d; range: 1-30d). Thirty-nine cases (68.4%) presented within 7d and 27 cases (47.4%) were culture positive. Two hundred and twenty-three age and gender matched controls were selected. In multivariate analysis, endophthalmitis was associated with posterior capsular rupture (PCR) during surgery (OR 6.98, 95%CI: 2.22-21.98), phacoemulsification via scleral incision with a foldable intraocular lens (IOL) implantation (OR 3.02, 95%CI: 1.13-8.04) and ocular co-morbidity (OR 2.32, 95%CI: 1.11-4.87).coNCLUSIONPCR, presence of ocular co-morbidity, and phacoemulsification via scleral incision with foldable-IOL were found to be independent risk factors for acute endophthalmitis.

关键词： endophthalmitis incidence cataract surgery risk factors