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Sonicating bees demonstrate flexible pollen extraction without instrumental learning

Current Zoology 2019年第4期65卷 425-436页

作者： Callin M. Switzer avery L. Russell daniel R. Papaj Stacey A. Combes Robin Hopkins Department of Organismic and Evolutionary Biology Harvard University Cambridge MA USA Arnold Arboretum Harvard University Boston MA USA Department of Ecology and Evolutionary Biology University of Arizona Tucson AZ USA Department of Neurobiology Physiology and Behavior University of California at Davis Davis CA USA Department of Biology and eScience Institute University of Washington Seattle WA USA Department of Biological Sciences University of Pittsburgh Pittsburgh PA USA

Pollen collection is necessary for bee survival and important for flowering plant reproduction, yet if and how pollen extraction motor routines are modified with experience is largely unknown. Here, we used an automated reward and monitoring system to evaluate modification in a common pollen-extraction routine, floral sonication. Through a series of laboratory experiments with the bumblebee, Bombus impatiens, we examined whether variation in sonication frequency and acceleration is due to instrumental learning based on rewards, a fixed behavioral response to rewards, and/or a mechanical constraint. We first investigated whether bees could learn to adjust their sonication frequency in response to pollen rewards given only for specified frequency ranges and found no evidenee of instrumental learning. However, we found that absenee versus receipt of a pollen reward did lead to a predictable behavioral resp on se, which depe nded on bee size. Fin ally, we found some evide nee of mechanical con straints, in that flower mass affected sonication acceleration (but not frequency) through an interaction with bee size. In generalz larger bees showed more flexibility in sonication frequency and acceleration, potentially reflecting a size-based constraint on the range over which smaller bees can modify frequency and accelerati on. Overall our results show that although bees did not display instrumental learning of sonication frequency, their sonication motor routine is nevertheless flexible.

关键词： Bombus impatiens buzz pollination foraging innate behavior learned behavior Solanum

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Multimorbidity patterns and association with mortality in 0.5 million Chinese adults

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Chinese Medical Journal 2022年第6期135卷 648-657页

作者： Junning Fan Zhijia Sun Canqing Yu Yu Guo Pei Pei Ling Yang Yiping Chen Huaidong Du Dianjianyi Sun Yuanjie Pang Jun Zhang Simon Gilbert Daniel Avery Junshi Chen Zhengming Chen Jun Lyu Liming Li On Behalf of the China Kadoorie Biobank Collaborative Group Department of Epidemiology and Biostatistics School of Public HealthPeking UniversityBeijing 100191China Peking University Center for Public Health and Epidemic Preparedness and Response Peking UniversityBeijing 100191China National Clinical Research Center of Cardiovascular Diseases National Center for Cardiovascular DiseasesFuwai HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100037China China Kadoorie Biobank National Coordination Centre Chinese Academy of Medical SciencesBeijing 100730China Nuffield Department of Population Health Medical Research Council Population Health Research UnitUniversity of OxfordOxford OX37LFUnited Kingdom Nuffield Department of Population Health University of OxfordClinical Trial Service Unit and Epidemiological Studies Unit(CTSU)Oxford OX37LFUnited Kingdom Suzhou Center for Disease Control and Prevention SuzhouJiangsu 215004China China National Center for Food Safety Risk Assessment Beijing 100022China Key Laboratory of Molecular Cardiovascular Sciences Peking UniversityMinistry of EducationBeijing 100191China 不详

Background:Few studies have assessed the relationship between multimorbidity patterns and mortality risk in the Chinese population.We aimed to identify multimorbidity patterns and examined the associations of multimorbidity patterns and the number of chronic diseases with the risk of mortality among Chinese middle-aged and older adults.Methods:We used data from the China Kadoorie Biobank and included 512,723 participants aged 30 to 79 years.Multimorbidity was defined as the presence of two or more of the 15 chronic diseases collected by self-report or physical examination at baseline.Multimorbidity patterns were identified using hierarchical cluster analysis.Cox regression was used to estimate the associations of multimorbidity patterns and the number of chronic diseases with all-cause and cause-specific mortality.Results:Overall,15.8%of participants had multimorbidity.The prevalence of multimorbidity increased with age and was higher in urban than rural participants.Four multimorbidity patterns were identified,including cardiometabolic multimorbidity(diabetes,coronary heart disease,stroke,and hypertension),respiratory multimorbidity(tuberculosis,asthma,and chronic obstructive pulmonary disease),gastrointestinal and hepatorenal multimorbidity(gallstone disease,chronic kidney disease,cirrhosis,peptic ulcer,and cancer),and mental and arthritis multimorbidity(neurasthenia,psychiatric disorder,and rheumatoid arthritis).During a median of 10.8 years of follow-up,49,371 deaths occurred.Compared with participants without multimorbidity,cardiometabolic multimorbidity(hazard ratios[HR]=2.20,95%confidence intervals[CI]:2.14-2.26)and respiratory multimorbidity(HR=2.13,95%CI:1.97-2.31)demonstrated relatively higher risks of mortality,followed by gastrointestinal and hepatorenal multimorbidity(HR=1.33,95%CI:1.22-1.46).The mortality risk increased by 36%(HR=1.36,95%CI:1.35-1.37)with every additional disease.Conclusion:Cardiometabolic multimorbidity and respiratory multimorbidity posed the highest threat on mortality risk and d

关键词： Multimorbidity Pattern Mortality Chinese

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The weekend effect:does time of admission impact management and outcomes of small bowel obstruction?

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Gastroenterology Report 2014年第3期2卷 221-225页

作者： Derek P.McVay avery S.Walker daniel W.Nelson Christopher R.Porta Marlin W.Causey Tommy A.Brown Department of Surgery Madigan Healthcare SystemTacomaWAUSA

Aims:To determine whether day and time of admission influences the practice patterns of the admitting general surgeon and subsequent outcomes for patients diagnosed with small bowel obstruction.Methods:A retrospective database review was carried out,covering patients admitted with the presumed diagnosis of partial small bowel obstruction from 2004–2011.Results:A total of 404 patients met the inclusion criteria.One hundred and thirty-nine were admitted during the day,93 at night and 172 on the weekend.Overall 30.2%of the patients were managed operatively with no significant difference between the groups(P=0.89);however,of patients taken to the operating room,patients admitted during the day received operative intervention over 24 hours earlier than those admitted at a weekend,0.79 days vs 1.90 days,respectively(P=0.05).Overall mortality was low at 1.7%,with no difference noted between the groups(P=0.35).Likewise there was no difference in morbidity rates between the three groups(P=0.90).Conclusions:Despite a faster time to operative intervention in those patients admitted during the day,our study revealed that time of admission does not appear to correlate to patient outcome or mortality.

关键词： small bowel obstruction weekend effect time of admission outcomes

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