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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

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.

Fluorescence Intensity Decay Shape Analysis Microscopy （FIDSAM） for Quantitative and Sensitive Live-Cell Imaging： A Novel Technique for Fluorescence Microscopy of Endogenously Expressed Fusion-Proteins

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Molecular Plant 2010年第3期3卷 555-562页

作者： Frank Schleifenbaum Kirstin Elgass Marcus Sackrow Katharina Caesar kenneth Berendzen Alfred j. Meixner Klaus Hatter Center for Plant Molecular Biology Department of Plant Physiology University of Tubingen Auf der Morgenstelle 1 72076 Tubingen Germany Institute of Physical and Theoretical Chemistry University of Tubingen Auf der Morgenstelle 8 72076 Tubingen Germany

Fluorescent studies of living plant cells such as confocal microscopy and fluorescence lifetime imaging often suffer from a strong autofluorescent background contribution that significantly reduces the dynamic image contrast and the quantitative access to sub-cellular processes at high spatial resolution. Here, we present a novel technique--fluorescence intensity decay shape analysis microscopy （FIDSAM） to enhance the dynamic contrast of a fluorescence image of at least one order of magnitude. The method is based on the analysis of the shape of the fluorescence intensity decay （fluorescence lifetime curve） and benefits from the fact that the decay patterns of typical fluorescence label dyes strongly differ from emission decay curves of autofluorescent sample areas. Using FIDSAM, we investigated Arabidopsis thaliana hypocotyl cells in their tissue environment, which accumulate an eGFP fusion of the plasma membrane marker protein LTI6b （LTI6b-eGFP） to low level. Whereas in conventional confocal fluorescence images, the membranes of neighboring cells can hardly be optically resolved due to the strong autofluorescence of the cell wall, FIDSAM allows for imaging of single, isolated membranes at high spatial resolution. Thus, FIDSAM will enable the sub-cellular analysis of even low-expressed fluorophoretagged proteins in living plant cells. Furthermore, the combination of FIDSAM with fluorescence lifetime imaging provides the basis to study the local physico-chemical environment of fluorophore-tagged biomolecules in living plant cells.

关键词： Cell structure cell walls membrane proteins high-resolution fluorescence microscopy.

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

Retrograde j.j.noduodenogastric intussusception due to a replacement percutaneous gastrostomy tube presenting as upper gastrointestinal bleeding

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World j.urnal of Gastroenterology 2007年第39期13卷 5282-5284页

作者： Eric Ibegbu Manish Relan kenneth j.Vega Divisions of Gastroenterology and General Internal Medicine University of Florida Health Science Center/Jacksonville Jacksonville FL32207 United States

Percutaneous endoscopic gastrostomy (PEG) tube complications can be serious or life threatening. Retrograde intussusception is a very rare complication of PEG tubes with only 9 cases reported in the literature. We describe a case of retrograde intussusception, associated with the use of a Foley catheter as a replacement gastrostomy tube, presenting with upper gastrointestinal bleeding. To our knowledge, this is the first reported case of PEG-related retrograde intussusception successfully managed in a non-surgical manner. Retrograde intussusception likely occurred due to migration of the replacement tube with resultant securing and invagination of the proximal j.j.num when the gastrostomy tube was anchored to the abdominal wall.

关键词： Percutaneous endoscopic gastrostomy Intussusception Migration and upper gastrointestinal bleeding

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

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.

Tumor-associated methylation of the putative tumor suppressor Aj.P1 gene and association between decreased Aj.P1 expression and shorter survival in patients with glioma

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Chinese j.urnal of Cancer 2011年第4期30卷 247-253页

作者： David Cogdell Woonbok Chung Yuexin Liu j. Matthew McDonald kenneth Aldape j.an-Pierre j. Issa Gregory N. Fuller Wei Zhang Department of Pathology The University of Texas MD Anderson Cancer Center Houston Texas 77030 USA Department of Leukemia The University of Texas MD Anderson Cancer Center Houston Texas 77030 USA.

Allelic loss of the short arm of chromosome 1 has been observed frequently in a wide spectrum of cancers,most frequently in *** our previous studies,we evaluated 177 oligodendroglial tumor samples and identified the Aj.P1 gene(formerly Shrew1) in the consensus region of ***1 is a transmembrane protein found in adheren j.nctions and functions to inhibit glioma cell adhesion and *** a putative tumor suppressor gene,we did not detect Aj.P1 gene *** subsequent studies,we found that Aj.P1 was underexpressed in oligodendrogliomas relative to normal brain *** analysis revealed the presence of CpG islands in the promoter of *** analysis of the Aj.P1 promoter identified hypermethylation in 21% of oligodendrogliomas(n = 27),and the degree of methylation correlated with low levels of Aj.P1 expression(P = 0.045).The Aj.P1 promoter was also highly methylated in a wide spectrum of cell lines(n = 22),including cell lines of *** of the National Cancer Institute's REMBRANDT dataset,which contains 343 glioma samples,indicated that low Aj.P1 gene expression was associated with decreased ***,both genetic(gene deletion) and epigenetic alterations(promoter methylation) are likely mechanisms that inactivate the putative tumor suppressor Aj.P1 in gliomas,which contributes to poor prognosis.

关键词：甲基化分析脑胶质瘤抑癌基因 P1基因肿瘤患者协会少突胶质细胞