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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 j.mie D, COSTABILE kenneth j. RENNER j.hn 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.

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

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 j.zmine D. W. YAEGER kenneth j. RENNER j.hn 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.

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

Biparental behavior in the burying beetle Nicrophorus orbicollis： a role for dopamine？

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Current Zoology 2016年第3期62卷 285-291页

作者： S. Carmen PANAITOF j.zmine D. W. YAEGER j.rod P. SPEER kenneth j. RENNER Department of Biology UniversiW of Nebraska at Keamey Kearney NE 68849 USA Department of Biology University of South Dakota Vermillion SD 57069 USA

Burying beetles Nicrophorus orbicollis exhibit facultative biparental care of young. To reproduce, a male-female burying beetle pair bury and prepare a small vertebrate carcass as food for its altricial young. During a breeding bout, male and female behavior changes synchronously at appropriate times and is coordinated to provide effective care for offspring. Although the ecologicaj.and evolutionary factors that shape this remarkable reproductive plasticity are well characterized, the neuromodulation of parental behavior is poorly understood. j.venile hormone levels rise dramat- ically at the time beetle parents accept and feed larvae, remain highly elevated during the stages of most active care and fall abruptly when care is terminated. However, hormonal fluctuations alone cannot account for this elaborate control of reproduction. The biogenic amines octopamine （OA）, dopamine （DA）, and serotonin （5-HT） mediate a diversity of insect reproductive and social behav- iors. In this study, we measured whole brain monoamine levels in individual male and female bury- ing beetles and compared OA, DA, and 5-HT profiles between breeding （parental） and nonbreed- ing, unmated beetles. Remarkably, after 24 h of care, when parental feeding rates begin to peak, DA brain levels increase in breeding beetles when compared to nonbreeding controls. In contrast, brain OA and 5-HT levels did not change significantly. These results provide the first evidence for a potential role of DA in the modulation of burying beetle parental behavior.

关键词： dopamine Nicrophorus neuromodulation octopamine parental care serotonin.

Characterization of ASTER GDEM elevation data over vegetated area compared with lidar data

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International j.urnal of Digital Earth 2015年第3期8卷 198-211页

作者： Wenj.an Ni Guoqing Sun kenneth j.Ranson State Key Laboratory of Remote Sensing Science Institute of Remote Sensing and Digital EarthChinese Academy of SciencesBeijingChina Department of Geographical sciences University of MarylandCollege ParkMDUSA Biospheric Sciences Branch NASA’s Goddard Space Flight CenterGreenbeltMDUSA

Current researches based on areal or spaceborne stereo images with very high resolutions(<1 m)have demonstrated that it is possible to derive vegetation height from stereo *** second version of the Advanced Spaceborne Thermal Emission and Reflection Radiometer Global Digital Elevation Model(ASTER GDEM)is the state-of-the-art global elevation data-set developed by stereo ***,the resolution of ASTER stereo images(15 m)is much coarser than areal stereo images,and the ASTER GDEM is compiled products from stereo images acquired over 10 *** forest disturbances as well as forest growth are inevitable in 10 years time *** this study,the features of ASTER GDEM over vegetated areas under both flat and mountainous conditions were investigated by comparisons with lidar *** factors possibly affecting the extraction of vegetation canopy height considered include(1)co-registration of DEMs;(2)spatial resolution of digital elevation models(DEMs);(3)spatial vegetation structure;and(4)terrain *** results show that the accurate coregistration between ASTER GDEM and national elevation dataset(NED)is necessary over mountainous *** correlation between ASTER GDEM minus NED and vegetation canopy height is improved from 0.328 to 0.43 by degrading resolutions from 1 arc-second to 5 arc-second and further improved to 0.6 if only homogenous vegetated areas were considered.

关键词： vegetation canopy height ASTER GDEM NED photogrammetry stereo-mapping

Uptake and transformation of arsenic during the reproductive life stage of Agaricus bisporus and Agaricus campestris

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j.urnal of Environmental Sciences 2016年第11期28卷 140-149页

作者： Michelle M.Nearing Iris Koch kenneth j.Reimer Environmental Sciences Group Royal Military College of Canada

Fruiting bodies from the Agaricus genus have been found to contain non-toxic arsenobetaine（AB） as a maj.r compound. It is unknown whether AB is formed during the vegetative or reproductive life stages of the fungus, or by the surrounding microbial community, but AB＇s structural similarity to glycine betaine has led to the hypothesis that AB may be adventitiously accumulated as an osmolyte. To investigate the potential formation of AB during the reproductive life stage of Agaricus species, growth substrate and fungi were collected during the commercial growth of Agaricus bisporus and analyzed for arsenic speciation using HPLC-ICP-MS. AB was found to be the maj.r arsenic compound in the fungus at the earliest growth stage of fruiting（the primordium）. The growth substrate mainly contained arsenate（As（V））. The distribution of arsenic in an A. bisporus primordium grown on As（V） treated substrate, and in a mature Agaricus campestris fruiting body collected from arsenic contaminated mine tailings, was mapped using two dimensional XAS imaging. The primordium and stalk of the mature fruiting body were both found to be growing around pockets of substrate material containing higher As concentrations, and AB was found exclusively in the fungal tissues. In the mature A. campestris the highest proportion of AB was found in the cap, supporting the AB as an osmolyte hypothesis. The results have allowed us to pinpoint the fungus life stage at which AB formation takes place,namely reproduction, which provides a direction for further research.

关键词： Arsenobetaine Arsenic Agaricus Fungi HPLC-ICP-MS XAS imaging

Endoscopic foregut surgery and interventions:The future is *** state-of-the-art and my personal j.urney

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World j.urnal of Gastroenterology 2019年第1期25卷 1-41页

作者： kenneth j.Chang H.H.Chao Comprehensive Digestive Disease Center University of CaliforniaIrvine Medical CenterOrangeCA 92868United States

In this paper, I reviewed the emerging field of endoscopic surgery and present data supporting the contention that endoscopy can now be used to treat many foregut diseases that have been traditionally treated surgically. Within each topic,the content will progress as follows: "lessons learned", "technical considerations"and "future opportunities". Lessons learned will provide a brief background and update on the most current literature. Technical considerations will include my personal experience, including tips and tricks that I have learned over the ***, future opportunities will address current unmet needs and potential new areas of development. The foregut is defined as "the upper part of the embryonic alimentary canal from which the pharynx, esophagus, lung, stomach, liver,pancreas, and part of the duodenum develop". Foregut surgery is well established in treating conditions such as gastroesophageal reflux disease(GERD), achalasia, esophageal diverticula, Barrett's esophagus(BE) and esophageal cancer, stomach cancer, gastric-outlet obstruction, and obesity. Over the past decade, remarkable progress in interventional endoscopy has culminated in the conceptualization and practice of endoscopic foregut surgery for various clinical conditions summarized in this paper. Regarding GERD, there are now several technologies available to effectively treat it and potentially eliminate symptoms, and the need for long-term treatment with proton pump *** the first time, fundoplication can be performed without the need for open or laparoscopic surgery. Long-term data going out 5-10 years are now emerging showing extended durability. In respect to achalasia, per-oral endoscopic myotomy(POEM) which was developed in j.pan, has become an alternative to the traditional Heller's myotomy. Recent meta-analysis show that POEM may have better results than Heller, but the issue of post-POEM GERD still needs to be addressed. There is now a resurgence of endoscopic tre

关键词： Endoscopy Foregut diseases Gastroesophageal reflux disease Endoscopic sleeve gastroplasty Endoscopic submucosal dissection Per-oral endoscopic myotomy Endo-hepatology

PRELIMINARY PALEOMAGNETIC EVIDENCE FOR EARLY TRIASSIC SEPARATION OF THE HUANAN AND YANGTZE BLOCKS, SOUTH CHINA

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Chinese Science Bulletin 1992年第15期37卷 1297-1301页

作者：陈海泓孙枢李继亮 kenneth j. HSU FRIEDRICH HELLER j.N DOBSON Laboratory of Lithosphere Tectonic Evolution Institute of Geology Academia Sinica Beijing 100029 PRC Swiss Federal Institute of Technology CH-8092 Zurich

South China comprises three distinct lithospheric blocks, namely the Yangtze, Huanan and Dongnanya (Southeast Asia) blocks according to the hypothesis of 'Mesozoic collisional orogenies of South China' . The Yangtze a... 详细信息

关键词： paleomagnetism early Triassic Huanan Block Yangtze Block.