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Neurochemistry as a bridge between morphology and behavior： Perspectives on aggression in insects

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Current Zoology 2014年第6期60卷 778-790页

作者： Andrew N. BUBAK jaime L. GRACE Michael j. WATT kenneth.j. renner john G. SWALLOW Neuroscience Program University of Colorado-Denver Anschutz Medical Campus Aurora CO 80045 USA Department of Integrative Biology University of Colorado-Denver Denver CO 80217-3364 USA Center for Brain and Behavior Research Basic Biomedical Sciences University of South Dakota Vermillion SD 57069 USA Department of Biology University of South Dakota Vermillion SD 57069 USA

Aggression is a common behavioral trait shared in many animals, including both vertebrates and invertebrates. However, the type and intensity of agonistic encounters and displays can vary widely both across and within species, resulting in complicated or subjective interpretations that create difficulties in developing theoretical models that can be widely applied. The need to easily and objectively identify quantifiable behaviors and their associated morphologies becomes especially important when attempting to decipher the neurological mechanisms underlying this complex behavior. Monoamines, neuropeptides, and pheromones have been implicated as important neuromodulators for agonistic displays in both invertebrates and vertebrates. Ad- ditionally, recent breakthroughs in insect research have revealed exciting proximate mechanisms important in aggression that may be broadly relevant, due to the relatively high conservation of these neurochemical systems across animal taxa. In this review, we present the latest research demonstrating the importance of monoamines, neuropeptides, and pheromones as neuromodulators for aggression across a variety of insect species. Additionally, we describe the stalk-eyed fly as a model system for studying aggres- sion, which integrates physiological, morphological, and neurochemical approaches in exploring detailed mechanisms responsible for this common yet complex behavior. We conclude with our perspective on the most promising lines of future research aimed at understanding the proximate and ultimate mechanisms underlying aggressive behaviors .

关键词： Monoamines Aggression Insects Evolutionary physiology Sexual Selection

Assessment strategies and fighting patterns in animal contests： a role for serotonin？

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Current Zoology 2016年第3期62卷 257-263页

作者： Andrew N. BUBAK Alison R. GERKEN Michael j. WATT jamie D, COSTABILE kenneth.j. renner john G. SWALLOW Integrative Biology University of Colorado-Denver Denver CO 80217-3364 USA Molecular Genetics and Microbiology University of Florida Gainesville FL 32611 USA Center for Brain and Behavior Research Basic Biomedical Sciences University of South Dakota Vermillion SD 57069 USA Biology Department University of South Dakota Vermillion SD 57069 USA

Accurate assessment of the probability of success in an aggressive confrontation with a conspecific is critical to the survival and fitness of the individuals. Various game theory models have examined these assessment strategies under the assumption that contests should favor the animal with the greater resource-holding potential （RHP）, body size typically being the proxy. Mutual assessment asserts that an individual can assess their own RHP relative to their opponent, allowing the inferior animal the chance to flee before incurring unnecessary costs. The model of self-determined persistence, however, assumes that an individual will fight to a set personal threshold, independ- ent of their opponent＇s RHP. Both models have been repeatedly tested using size as a proxy for RHP, with neither receiving unambiguous support. Here we present both morphological and neuro- physiological data from size-matched and mismatched stalk-eyed fly fights. We discovered differ- ing fighting strategies between winners and losers. Winners readily escalated encounters to higher intensity and physical contact and engaged in less low-intensity, posturing behaviors compared with losers. Although these fighting strategies were largely independent of size, they were associ- ated with elevated levels of 5-HT. Understanding the neurophysiological factors responsible for mediating the motivational state of opponents could help resolve the inconsistencies seen in cur- rent game theory models. Therefore, we contend that current studies using only size as a proxy for RHP may be inadequate in determining the intricacies of fighting ability and that future studies investigating assessment strategies and contest outcome should include neurophysiological data.

关键词： aggression assessment fighting strategies serotonin monoamines resource-holding potential.

A review of current understanding in tribochemical reactions involving lubricant additives

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Friction 2023年第4期11卷 489-512页

作者： Yan CHEN Peter renner Hong LIANG Department of Materials Science and Engineering Texas A&M UniversityCollege Station 77843USA j.Mike Walker’66 Department of Mechanical Engineering Texas A&M UniversityCollege Station 77843USA

Lubricants have played important roles in friction and wear reduction and increasing efficiency of mechanical *** optimize tribological performance,chemical reactions between a lubricant and a substrate must be designed *** reactions are chemical reactions enabled or accelerated by mechanical *** activated lubricant additives play important roles in these *** this review,current understanding in mechanisms of chemical reactions under shear has been *** such as oil-soluble organics,ionic liquids(ILs),and nanoparticles(NPs)were analyzed in relation to the tribochemical reaction routes with elements in metallic *** results indicated that phosphorus,sulfur,fluorine,and nitrogen are key elements for tribochemical *** resulting tribofilms from zinc dithiophosphates(ZDDP)and molybdenum dithiocarbamate(MoDTC)have been widely reported,yet that from ILs and NPs need to investigate *** review serves as a reference for researchers to design and optimize new lubricants.

关键词： lubricant additives tribochemical reactions oil-soluble organics ionic liquids(ILs) nanoparticles(NPs)

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 ter- ritory 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 nest- mate 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 ag- gression. In this article, we develop and explore an agent-based model that conceptualizes how in- dividual changes in brain concentrations of 5-HT and OA, paired with a simple threshold-based de- cision 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： agent-based model aggressive behavior ants decision making monoamines octopamine serotonin.

Liver surgery in cirrhosis and portal hypertension

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World journal of Gastroenterology 2016年第9期22卷 2725-2735页

作者： Christina Hackl Hans j Schlitt Philipp renner Sven A Lang Department of Surgery University Medical Center Regensburg

The prevalence of hepatic cirrhosis in Europe and the United States, currently 250 patients per 100000 inhabitants, is steadily increasing. Thus, we observe a significant increase in patients with cirrhosis and portal hypertension needing liver resections for primary ormetastatic lesions. However, extended liver resections in patients with underlying hepatic cirrhosis and portal hypertension still represent a medical challenge in regard to perioperative morbidity, surgical management and postoperative outcome. The Barcelona Clinic Liver Cancer classification recommends to restrict curative liver resections for hepatocellular carcinoma in cirrhotic patients to early tumor stages in patients with Child A cirrhosis not showing portal hypertension. However, during the last two decades, relevant improvements in preoperative diagnostic, perioperative hepatologic and intensive care management as well as in surgical techniques during hepatic resections have rendered even extended liver resections in higher-degree cirrhotic patients with portal hypertension possible. However, there are few standard indications for hepatic resections in cirrhotic patients and risk stratifications have to be performed in an interdisciplinary setting for each individual patient. We here review the indications, the preoperative risk-stratifications, the morbidity and the mortality of extended resections for primary and metastatic lesions in cirrhotic livers. Furthermore, we provide a review of literature on perioperative management in cirrhotic patients needing extrahepatic abdominal surgery and an overview of surgical options in the treatment of hepatic cirrhosis.

关键词： Liver resection Hepatocellular carcinoma Liver metastases Portal hypertension Cholangiocellular carcinoma Cirrhosis

Diabetes mellitus as a risk factor for gastrointestinal cancer among American veterans

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World journal of Gastroenterology 2009年第42期15卷 5274-5278页

作者： M Mazen jamal Eugene j Yoon kenneth.j.Vega Mehrtash Hashemzadeh kenneth.j.Chang Division of Gastroenterology Veterans Affairs(VA) Medical CenterLong BeachCA 90822United States Division of Gastroenterology Department of Internal MedicineCollege of MedicineUniversity of CaliforniaIrvine Medical CenterOrangeCA 92868United States Division of Gastroenterology University of Florida/JacksonvilleJacksonvilleFL 32207United States

AIM:To assess the risk of biliary and pancreatic cancers in a large cohort of patients with type 2 diabetes mellitus(DM) .METHODS:Eligibility for this study included patients with type 2 DM(ICD-9 code 250.0) who were discharged from Department of Veteran Affairs hospitals between 1990 and ***-matched control patients without DM were selected from the same patient treatment files during the same *** information included age,sex and *** diagnoses included known risk factors based on their ICD-9 *** multivariate logistic regression,the occurrence of biliary and pancreatic cancer was compared between case subjects with DM and controls without ***:A total of 1172496 case and control subjects were *** mean age for study and control subjects was 65.8 ± 11.3 and 64.8 ± 12.6 years,*** frequency of pancreatic cancer in subjects with DM was increased(0.9%) in comparison to control subjects(0.3%) with an OR of 3.22(95% CI:3.03-3.42) .The incidence of gallbladder andextrahepatic biliary cancers was increased by twofold in diabetic patients when compared to *** OR and 95% CI were 2.20(1.56-3.00) and 2.10(1.61-2.53) ,***:Our study demonstrated that patients with DM have a threefold increased risk for developing pancreatic cancer and a twofold risk for developing biliary cancer.

关键词： Diabetes mellitus Pancreatic neoplasms Adenocarcinoma Gallbladder neoplasms

Power regulation of kinematic control inputs for forward flying Drosophila

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Acta Mechanica Sinica 2014年第6期30卷 809-818页

作者： kenneth MacFarlane Imraan Faruque j.Sean Humbert 3181 Glenn L Martin Hall University of MarylandCollege Park MD 20742 USA

The choices of insect wing kinematic programs is not well understood,particularly the mechanism by which an insect selects a distortion to achieve flight control.A methodology to evaluate prospective kinematic control inputs is presented based on the reachable states when control actuation was constrained to a unit of *** method implements a computationally-derived reduced order model of the insect’s flight dynamics combined with calculation of power *** kinematic inputs are evaluated based on this criterion for a Drosophila size insect in forward *** bias is shown to be the dominant control input using this power normalized evaluation measure.

关键词： Flight control Control Drosophila Power

Intraocular lens power calculation in eyes with previous corneal refractive surgery

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Eye and Vision 2018年第1期5卷 172-181页

作者： Giacomo Savini kenneth.j.Hoffer G.B.Bietti Eye Foundation RomeItaly. Stein Eye Institute University of CaliforniaLos AngelesCAUSA.3 St.Mary’s Eye CenterSanta MonicaCAUSA

Background:This review aims to explain the reasons why intraocular lens(IOL)power calculation is challenging in eyes with previous corneal refractive surgery and what solutions are currently available to obtain more accurate ***:After IOL implantation in eyes with previous LASIK,PRK or RK,a refractive surprise can occur because (i)the altered ratio between the anterior and posterior corneal surface makes the keratometric index invalid;(ii)the corneal curvature radius is measured out of the optical zone;and (iii)the effective lens position is erroneously predicted if such a prediction is based on the post-refractive surgery corneal *** methods are currently available to obtain the best refractive outcomes in these eyes,even when the perioperative data(*** corneal power and surgically induced refractive change)are not *** this review,we describe the most accurate methods based on our clinical ***:IOL power calculation after myopic corneal refractive surgery can be calculated with a variety of methods that lead to relatively accurate outcomes,with 60 to 70%of eyes showing a prediction error within 0.50 diopters.

关键词： Cataract Intraocular lens power LASIK PRK Excimer laser Corneal surgery Keratometry

A fossil-calibrated relaxed clock for Ephedra indicates an Oligocene age for the divergence of Asian and New World clades and Miocene dispersal into South America

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journal of Systematics and Evolution 2009年第5期47卷 444-456页

作者： Stefanie M.ICKERT-BOND Catarina RYDIN Susanne S.renner University of Alaska UA Museum of the North Herbarium and Institute of Arctic Biology Institute of Systematic Botany University of Zurich University of Munich Systematic Botany and Mycology

Ephedra comprises approximately 50 species,which are roughly equally distributed between the Old and New World deserts,but not in the intervening regions(amphitropical range).Great heterogeneity in the substitution rates of Gnetales(Ephedra,Gnetum,and Welwitschia) has made it difficult to infer the ages of the major divergence events in Ephedra,such as the timing of the Beringian disjunction in the genus and the entry into South ***,we use data from as many Gnetales species and genes as available from GenBank and from a recent study to investigate the timing of the major divergence *** of the tradeoff between the amount of missing data and taxon/gene sampling,we reduced the initial matrix of 265 accessions and 12 loci to 95 accessions and 10 loci,and further to 42 species(and 7736 aligned nucleotides) to achieve stationary distributions in the Bayesian molecular clock *** from a relaxed clock with an uncorrelated rates model and fossil-based calibration reveal that New World species are monophyletic and diverged from their mostly Asian sister clade some 30 mya,fitting with many other Beringian *** split between the single North American and the single South American clade occurred approximately 25 mya,well before the closure of the Panamanian ***,the biogeographic history of Ephedra appears dominated by long-distance dispersal,but finer-scale studies are needed to test this hypothesis.

关键词： biogeography Ephedra relaxed molecular clock dating uncorrelated rates model.