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The organization of societal conflicts by pavement ants Tetramorium caespitum： an agent-based model of amine-mediated decision making

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Current Zoology 2016年第3期62卷 277-284页

作者： Kevin M. hoover Andrew n. BUBAK Isaac j. LAW jazmine D. W. YAEGER Kenneth j. REnnER john G. SWALLOW Michael j. GREEnE Department of Integrative Biology University of Colorado Denver Denver CO 80217-3364 USA neuroscience Program University of Colorado Anschutz Medical Campus Aurora CO 80045 USA Department of Biology University of South Dakota Vermillion South Dakota 57069 USA

Ant colonies self-organize to solve complex problems despite the simplicity of an individual ant's brain. Pavement ant Tetramorium caespitum colonies must solve the problem of defending the territory that they patrol in search of energetically rich forage. When members of 2 colonies randomly interact at the territory boundary a decision to fight occurs when: 1) there is a mismatch in nestmate recognition cues and 2) each ant has a recent history of high interaction rates with nestmate ants. Instead of fighting, some ants will decide to recruit more workers from the nest to the fighting location, and in this way a positive feedback mediates the development of colony wide wars. In ants, the monoamines serotonin (5-HT) and octopamine (OA) modulate many behaviors associated with colony organization and in particular behaviors associated with nestmate recognition and aggression. In this article, we develop and explore an agent-based model that conceptualizes how individual changes in brain concentrations of 5-HT and OA, paired with a simple threshold-based decision rule, can lead to the development of colony wide warfare. Model simulations do lead to the development of warfare with 91% of ants fighting at the end of 1 h. When conducting a sensitivity analysis, we determined that uncertainty in monoamine concentration signal decay influences the behavior of the model more than uncertainty in the decision-making rule or density. We conclude that pavement ant behavior is consistent with the detection of interaction rate through a single timed interval rather than integration of multiple interactions.

关键词：单胺类神经递质决策规则模型模拟体组织路面介导代理社会

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Targeted quantitative profiling of metabolites and gene transcripts associated with 4-aminobutyrate (GABA) in apple fruit stored under multiple abiotic stresses

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Horticulture Research 2018年第1期5卷 66-79页

作者： Carolyne j.Brikis Adel Zarei Greta Z.Chiu Kristen L.Deyman jingyun Liu Christopher P.Trobacher gord.n j.hoover Sanjeena Subedi jennifer R.DeEll Gale G.Bozzo Barry j.Shelp Department of Plant Agriculture University of GuelphGuelphOntarioN1G 2W1Canada Department of Mathematical Sciences Binghamton UniversityBinghamtonNY13902USA Ontario Ministry of Agriculture Food and Rural AffairsBox 5871283 Blueline Rd.at Highway 3SimcoeOntarioN3Y 4N5Canada

4-Aminobutyrate accumulates in plants under abiotic ***,targeted quantitative profiling of metabolites and transcripts was conducted to monitor glutamate-and polyamine-derived 4-aminobutyrate production and its subsequent catabolism to succinate or 4-hydroxybutyrate in apple(Malus x domestica Borkh.)fruit stored at 0°C with 2.5 kPa O2 and 0.03 or 5 kPa CO2 for 16 ***-temperature-induced protein hydrolysis appeared to be responsible for the enhanced availability of amino acids during early storage,and the resulting higher glutamate level stimulated 4-aminobutyrate levels more than *** CO2 increased the levels of polyamines,as well as succinate and 4-hydroxybutyrate,during early storage,and 4-aminobutyrate and 4-hydroxybutyrate over the longer *** of all of the genes likely involved in 4-aminobutyrate metabolism from glutamate/polyamines to succinate/4-hydroxybutyrate was induced in a co-ordinated ***2-regulated expression of apple GLUTAMATE DECARBOXYLASE 2,AMInE OXIDASE 1,ALDEHYDE DEHYDROGEnASE 10A8 and POLYAMInE OXIDASE 2 was evident with longer term *** suggested that respiratory activities were restricted by the elevated CO2/O2 environment,and that decreasing nAD+availability and increasing nADPH and nADPH/nADP+,respectively,played key roles in the regulation of succinate and 4-hydroxybutyate ***,these findings suggest that both transcriptional and biochemical mechanisms are associated with 4-aminobutyrate and 4-hydroxybutyrate metabolism in apple fruit stored under multiple abiotic stresses.

关键词： hydrolysis subsequent restricted

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A test of two mechanisms proposed to optimize grassland aboveground primary productivity in response to grazing

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journal of Plant Ecology 2012年第4期5卷 357-365页

作者： A.K.Knapp D.L.hoover j.M.Blair G.Buis D.E.Burkepile A.Chamberlain S.L.Collins R.W.S.Fynn K.P.Kirkman M.D.Smith D.Blake n.Govender P.O'neal T.Schreck A.Zinn Graduate Degree Program in Ecology and Department of Biology Colorado State UniversityFort CollinsCO 80526USA Division of Biology Kansas State UniversityManhattanKS 66506USA Department of Biological Sciences Florida International UniversityNorth MiamiFL 33181USA Department of Biology MSC03-2020University of New MexicoAlbuquerqueNM 87131USA Okavango Research Institute University of BotswanaPrivate Bag 285MaunBotswana School of Biological and Conservation Science University of KwaZulu-NatalPrivate Bag X01Scottsville 3209PietermaritzburgSouth Africa Department of Ecology and Evolutionary Biology Yale UniversityNew HavenCT 06520USA Scientific Services Kruger National ParkPrivate Bag X402Skukuza1350South Africa Department of Ecology and Evolutionary Biology University of CaliforniaIrvineCA 92697USA

Aims Mesic grasslands have a long evolutionary history of grazing by large herbivores and as a consequence,grassland species have numerous adaptations allowing them to respond favourably to *** empirical evidence has been equivocal,theory predicts that such adaptations combined with alterations in resources can lead to grazing-induced overcompensation in aboveground net primary production(AnPP;grazed AnPP>ungrazed AnPP)under certain *** tested two specific predictions from ***,overcompensation is more likely to occur in annually burned grasslands because limiting nutrients that would be lost with frequent fires are recycled through grazers and stimulate ***,overcompensation of biomass lost to grazers is more likely to occur in unburned sites where grazing has the greatest effect on increasing light availability through alterations in canopy *** We tested these nutrient versus light-based predictions in grazed grasslands that had been annually burned or protected from fire for>20 *** assessed responses in AnPP to grazing by large ungulates using both permanent and moveable grazing exclosures(252 exclosures from which biomass was harvested from 3192 quadrats)in a 2-year *** sites were located at the Konza Prairie Biological Station(KPBS)in north America and at Kruger national Park(KnP)in South *** KPBS,sites were grazed by north American bison whereas in KnP sites were grazed either by a diverse suite of herbivores(*** wildebeest,Burchell’s zebra,African buffalo)or by a single large ungulate(African buffalo).Important Findings We found no evidence for overcompensation in either burned or unburned sites,regardless of grazer ***,there was no support for either mechanism leading to ***,complete compensation of total biomass lost to grazers was the most common response characterizing grazing–AnPP relationships with,in some cases,undercompensation of grass AnPP being of

关键词： aboveground net primary production fire forbs herbivores savanna

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Gastroesophageal reflux disease after diagnostic endoscopy in the clinical setting

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World journal of Gastroenterology 2013年第16期19卷 2514-2520页

作者： nora B Zschau jane M Andrews Richard H Holloway Mark n Schoeman Kylie Lange William CE Tam Gerald j Holtmann Department of Gastroenterology and Hepatology Royal Adelaide Hospital Faculty of Health Sciences University of AdelaideAdelaide Department of Gastroenterology and Hepatology Lyell McEwin Hospital Department of Gastroenterology and Hepatology University of Queensland School of Medicine Princess Alexandra Hospital

AIM: To investigate the outcome of patients with symptoms of gastroesophageal reflux disease (GERD) referred for endoscopy at 2 and 6 mo post endoscopy. METHODS: Consecutive patients referred for upper endoscopy for assessment of GERD symptoms at two large metropolitan hospitals were invited to participate in a 6-mo non-interventional (observational) *** two institutions are situated in geographically and socially disparate areas. Data collection was by selfcompletion of questionnaires including the patient assessment of upper gastrointestinal disorders symptoms severity and from hospital records. Endoscopic finding using the Los-Angeles classification, symptom severity and it's clinically relevant improvement as change of at least 25%, therapy and socio-demographic factors were assessed. RESULTS: Baseline data were available for 266 patients and 2-mo and 6-mo follow-up data for 128 and 108 patients respectively. At baseline, 128 patients had erosive and 138 non-erosive reflux disease. Allmost all patient had proton pump inhibitor (PPI) therapy in the past. Overall, patients with non-erosive GERD at the index endoscopy had significantly more severe symptoms as compared to patients with erosive or even complicated GERD while there was no difference with regard to medication. After 2 and 6 mo there was a small, but statistically significant improvement in symptom severity (7.02 ± 5.5 vs 5.9 ± 5.4 and 5.5 ± 5.4 respectively); however, the majority of patients continued to have symptoms (i.e. , after 6 mo 81% with GERD symptoms). Advantaged socioeconomic status as well as being unemployed was associated with greater improvement. COnCLUSIOn: The majority of gord patients receive PPI therapy before being referred for endoscopy even though many have symptoms that do not sufficiently respond to PPI therapy.

关键词： Gastroesophageal reflux disease Epidemiology Proton pump inhibitor Acid suppressive therapy Endoscopy Barrett’s esophagus Functional gastrointestinal disorders

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Barrett食管及胃食管反流患者患食管癌的风险

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世界核心医学期刊文摘（胃肠病学分册） 2005年第1期1卷 38-39页

作者： Solaymani-Dodaran M. Logan R.F.A. West j. 杨雪娟 University of nottingham Div. of Epidemiol. and Public Health Queen's Medical CentreNottinghamNG7 2UHUnitedKingdom

Background and aims: While patients with Barrett s oesophagus develop oesophageal adenocarcinoma more fre quently than the general population, it has controversially been suggested that gastro-oesophageal reflux (gord) itself is a more important determinant of risk. In order to assess the validity of this suggestion, we examined the risk of oesophageal cancer in patients with Barrett s and with gord compared with the general population in a community based cohort study. Methods:Cohorts of patients with Barrett s (n = 1677), oesophagitis (n =6392), and simple reflux (n = 6328), and a reference cohort (n =13416)were selected from the General Practice Research *** last three cohortswere matched to the Barrett s cohort by general practitioner practice, age, and sex. Cox s regression analysis was used to calculate relative risks for oesophageal cancer. Standardised incidence ratio methodology was used to estimate the relative risks for oesophageal ***: A total of 137 oesophageal cancers were identified,of which 94 prevalent cases were excluded. The hazard ratios for oesophageal cancer were 10.6 (5.1-22.0), 2.2 (0.9-5.2), and 1.7 (0.7-4.5) in the Barrett s, oesophagitis, and reflux cohorts compared with the reference cohort, respectively. The corresponding relative risks for oesophageal adenocarcinoma were 29.8 (9.6-106), 4.5 (1.04-19.6), and 3.1 (0.6-14.2). Conclusion:Barrett s oesophagus increases the risk of oesophageal cancer approximately 10 times and oesophageal adenocarcinoma approximately 30 times compared with the general *** is only a modestly increased risk of oesophageal cancer in patients with reflux who have no record of Barrett s *** findings therefore do not support the suggestion that gastro-oesophageal reflux disease itself predisposes to cancer.

关键词：胃食管反流研究数据库管组全科医师队列研究全科医学身易

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失弛缓症患者血清可改变正常人胃底肠肌间神经丛化学信号和nO介导的反应

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世界核心医学期刊文摘（胃肠病学分册） 2006年第8期2卷 34-35页

作者： Bruley Des Varannes S. Chevalier j. Pimont S. M. neunlist 程妍(译) 陈云茹(校) 不详 InSERM U539 University Hospital HStel Dieu Place Alexis Ricordeau 44035 Nantes Cedex France

Background and aims: Achalasia is a disease of unknown aetiology. An immune mechanism has been suggested on the basis of previous morphological observations. The objective of this study was to test whether the serum of achalasia patients could reproduce the phenotype and functional changes that occur with disease progression in an ex vivo human model. Methods: Specimens of normal human fundus were maintained in culture in the presence of serum from patients with achalasia, gastro-oesophageal reflux disease (gord), or healthy subjects (controls). Immunohistochemical detection of choline acetyltransferase (ChAT), neurone specific enolase (nSE), vasoactive intestinal polypeptide (VIP), nitric oxide synthase (nOS), and substance P was carried out in whole mounts of gastric fundus myenteric plexus. In addition, the effects of achalasia serum on electrical field stimulation (EFS) induced contractions were measured in circular muscle preparations. Results: Serum from achalasia patients did not affect the number of myenteric neurones. Tissues incubated with serum from achalasia patients showed a decrease in the proportion of nOS (- 26% of nSE positive neurones; p = 0.016) and VIP (- 54% ; p = 0.09) neurones, and a concomitant increase in ChAT neurones (+ 16% ; pntrols. In contrast, gord serum did not modify the phenotype of myenteric neurones. Area under the curve of EFS induced relaxations (abolished by n-nitro-L-arginine methyl ester) was significantly decreased following incubation with serum from achalasia patients compared with controls (- 7.6 (2.6) v - 14.5 (5.0); p = 0.036). Conclusions: Serum from achalasia patients can induce phenotypic and functional changes which reproduce the characteristics of the disease. Further identification of putative seric factors and mechanisms involved could lead to the development of novel diagnostic and/or therapeutic strategies in achalasia.

关键词：肠血管活性多肽肌间神经丛失弛缓症收缩反应正常人患者血清 nO介导化学信号胃底

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