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Seeing red: color vision in the largemouth bass

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current Zoology 2019年第1期65卷 43-52页

作者： Lisa D. miTcHEm Shannon Stanis muchu Zhou Ellis LoEw john m. Epifanio Rebecca c. Fuller Department of Animal Biology School of Integrative Biology University of Illinois Champaign IL 61820 USA Department of Biomedical Sciences and Section of Physiology College of Veterinary Medicine Cornell University Ithaca NY 14853 USA Illinois Natural History Survey Champaign IL 61820 USA

How animals visually perceive the environment is key to understanding important ecological behaviors, such as predation, foraging, and mating. This study focuses on the visual system properties and visual perception of color in the largemouth bass micropterus salmoides. This study (1) doc.ments the number and spectral sensitivity of photoreceptors,(2) uses these parameters to model visual perception, and (3) tests the model of color perception using a behavioral assay. Bass possess single cone cells maximally sensitive at 535 nm, twin cone cells maximally sensitive at 614 nm, and rod cells maximally sensitive at 528 nm. A simple model of visual perception predicted that bass should not be able to discern between chartreuse yellow and white nor between green and blue. In contrast, bass should be able to discern red from all achromatic (i.e., gray scale) stimuli. These predictions were partially upheld in behavioral trials. In behavioral trials, bass were first trained to recognize a target color to receive a food reward, and then tested on their ability to differentiate between their target color and a color similar in brightness. Bass trained to red and green could easily discern their training color from all other colors for target colors that were similar in brightness (white and black, respectively). This study shows that bass possess dichromatic vision and do use chromatic (i.e., color) cues in making visual-based decisions.

关键词： bass cones photoreceptors rods vision

A Fractal measure of Spatial Association between Landslides and conditioning Factors

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Journal of Earth Science 2017年第4期28卷 588-594页

作者： Renguang Zuo Emmanuel john m.carranza State Key Laboratory of Geological Processes and mineral Resources China University of Geosciences Institute of Geosciences State University of Campinas (Uni Camp)

measuring the relative importance and assigning weights to conditioning factors of land- slides occurrence are significant for landslide prevention and/or mitigation. In this contribution, a fractal method is introduced for measuring the spatial relationships between landslides and condition- ing factors （such as faults, rivers, geological boundaries, and roads）, and for assigning weights to condi- tioning factors for mapping of landslide susceptibility. This method can be expressed as p=c~, where d is the fractal dimension, and c is a constant. This relationship indicates a fractal relation between land- slide density （p） and distances to conditioning factors （6）. The case of d〉0 suggests a significant spatial correlation between landslides and conditioning factors. The larger the d （〉0） value, the stronger the spatial correlation is between landslides and a specific conditioning factor. Two case studies in South china were examined to demonstrate the usefulness of this novel method.

关键词： geological hazard landslides fractal spatial statistic.

Disruption of colonic barrier function and induction of mediator release by strains of c.mpylobacter jejuni that invade epithelial cells

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World Journal of Gastroenterology 2008年第48期14卷 7345-7352页

作者： Johannes Beltinger Jo del Buono maeve m Skelly john Thornley Robin c Spiller William A Stack christopher J Hawkey Wolfson Digestive Diseases centre Nottingham University Hospital QMC Campus

AIm: To study the mechanisms by which c.mpylobacter jejuni (c. jejuni) causes inflammation and diarrhea. In particular, direct interactions with intestinal epithelial cells and effects on barrier function are poorly under- stood. mETHODS: To model the initial pathogenic effects of c. jejuni on intestinal epithelium, polarized human colonic HcA-7 monolayers were grown on permeabilized filters and infected apically with clinical isolates of c. jejuni. Integrity of the monolayer was monitored by changes in monolayer resistance, release of lactate dehydrogenase, mannitol fluxes and electron microscopy. Invasion of HcA-7 cells was assessed by a modified gentamicin protection assay, translocation by counting colony forming units in the basal chamber, stimulation of mediator release by immunoassays and secretory responses in monolayers stimulated by bradykinin in an Ussing chamber. RESULTS: All strains translocated across monolayers but only a minority invaded HcA-7 cells. Strains that invaded HcA-7 cells destroyed monolayer resistance over 6 h, acc.mpanied by increased release of lactate dehydrogenase, a four-fold increase in permeability to [3H] mannitol, and ultrastructural disruption of tight junctions, with rounding and lifting of cells off the filter membrane. Synthesis of interleukin (IL)-8 and prostaglandin E2 was increased with strains that invaded the monolayer but not with those that did not. cONcLUSION: These data demonstrate two distinct effects of c. jejuni on colonic epithelial cells and provide an informative model for further investigation of initial host cell responses to c. jejuni.

关键词： c.mpylobacter jejuni cell invasion cellculture chloride secretion colonocyte HcA-7 cells membrane permeability monolayer mucosal barrier Ussing chamber

Transdermal delivery of 4-aminopyridine accelerates motor functional recovery and improves nerve morphology following sciatic nerve crush injury in mice

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Neural Regeneration Research 2020年第1期15卷 136-144页

作者： Andrew Rclark chia George Hsu m A Hassan Talukder mark Noble john cElfar center for Orthopaedic Research and Translational Science Penn State Hershey College of MedicineMilton S.Hershey Medical CenterHersheyPAUSA Department of Orthopaedics The University of Rochester Medical CenterRochesterNYUSA Department of medicine Aab Cardiovascular Research InstituteUniversity of Rochester School of Medicine and DentistryRochesterNYUSA Department of Biomedical Genetics The University of Rochester Medical CenterRochesterNYUSA

Oral 4-aminopyridine(4-AP)is clinically used for symptomatic relief in multiple sclerosis and we recently demonstrated that systemic 4-AP had previously unknown clinically-relevant effects after traumatic peripheral nerve injury including the promotion of re-myelination,improvement of nerve conductivity,and acceleration of functional *** hypothesized that,instead of oral or injection administration,transdermal 4-AP(TD-4-AP)could also improve functional recovery after traumatic peripheral nerve *** with surgical traumatic peripheral nerve injury received TD-4AP or vehicle alone and were examined for skin permeability,pharmacokinetics,functional,electrophysiological,and nerve morphological properties.4-AP showed linear pharmacokinetics and the maximum plasma 4-AP concentrations were proportional to TD-4-AP *** a single dose of TD-4-AP administration demonstrated rapid transient improvement in motor function,chronic TD-4-AP treatment significantly improved motor function and nerve conduction and these effects were associated with fewer degenerating axons and thicker myelin sheaths than those from vehicle *** findings provide direct evidence for the potential transdermal applicability of 4-AP and demonstrate that 4-AP delivered through the skin can enhance in-vivo functional recovery and nerve conduction while decreasing axonal *** animal experiments were approved by the University c.mmittee on Animal Research(UcAR)at the University of Rochester(UcAR-2009-019)on march 31,2017.

关键词： 4-aminopyridine electron microscopy functional recovery nerve conduction velocity peripheral nerve injury pharmacokinetics transdermal administration

magnetic resonance studies of a gas-solids fluidised bed:Jet-jet and jet-wall interactions

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Particuology 2010年第6期8卷 617-622页

作者： meenal Pore Daniel J.Holland Thusara c.chandrasekera christoph R.müller Andrew J.Sederman john S.Dennis Lynn F.Gladden john F.Davidson Department of chemical Engineering and Biotechnology University of CambridgePembroke StreetCambridgeCB2 3RAUK Department of mechanical and Process Engineering ETH ZurichSonneggstrasse 38092 ZurichSwitzerland

magnetic resonance imaging （mRI） gave images of air jets from orifices in the distributor plate of a bed of poppy seeds. Attention focused on two features：（1） The interaction between nearby vertical jets from two, three or four orifices; （2） Wall effects, where one or more orifices created vertical jets near the vertical wall of the cylinder containing the particle bed. The results show that nearby jets are mutually attracted. Likewise a jet near a wall bends out of the vertical, towards the wall, For multiple adjacent jets, the jet lengths show dependence on orifice layout： the lengths are in reasonable agreement with published measurements, by other methods, for single jets. The mRI gives three-dimensional images of the single jets and of multiple jets, separate or merging.

关键词： Fluidised bed mRI Jets Distributor design

Gastrointestinal and liver disease in patients with schizophrenia:A narrative review

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World Journal of Gastroenterology 2022年第38期28卷 5515-5529页

作者： Rebecca K Grant William m Brindle mhairi c Donnelly Pauline m mcconville Thomas G Stroud Lorenzo Bandieri john N Plevris The centre for Liver and Digestive Disorders Royal Infirmary of EdinburghEdinburghEH164SAUnited Kingdom General Adult Psychiatry Royal Edinburgh HospitalEdinburghEH105HFUnited Kingdom

Schizophrenia is a severe mental illness which can have a devastating impact onan individual’s quality of life. c.morbidities are high amongst patients and lifeexpectancy is approximately 15 years less than the general population. Despite thewell-known increased mortality, little is known about the impact of gastrointestinaland liver disease on patients with schizophrenia. We aimed to reviewthe literature and to make rec.mmendations regarding future care. Literaturesearches were performed on Pubmed to identify studies related to gastrointestinaland liver disease in patients with schizophrenia. High rates of chronic liverdisease were reported, with Non-Alcoholic Fatty Liver Disease being of particularconcern;antipsychotics and metabolic syndrome were contributing factors. Ratesof acute liver failure were low but have been associated with antipsychotic useand paracetamol overdose. coeliac disease has historically been linked to schizophrenia;however, recent research suggests that a causal link is yet to be *** is emerging regarding the relationships between schizophrenia andpeptic ulcer disease, inflammatory bowel disease and irritable bowel syndrome;clinical vigilance regarding these conditions should be high. Patients with schizophreniapoorly engage with bowel cancer screening programmes, leading to latediagnosis and increased mortality. clozapine induced constipation is a significantissue for many patients and requires close monitoring. There is a significantburden of gastrointestinal and liver disease amongst patients with *** levels of support from all members of the medical team are essential toensure that appropriate, timely care is provided.

关键词： Schizophrenia Gastrointestinal disease Liver disease mental health

cyclooxygenase-2 and epithelial growth factor receptor up-regulation during progression of Barrett's esophagus to adenocarcinoma

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World Journal of Gastroenterology 2006年第6期12卷 928-934页

作者： Yan Li john m Wo mukunda B Ray Whitney Jones Ruifeng R Su Susan Ellis Robert c G martin Division of Surgical Oncology University of Louisville School ofMedicine Louisville KY 40202 United States Division of Gastroenterology/Hepatology University of Louisville School of MedicineLouisville KY 40202 United States Department of Anatomical Pathology University of Louisville School of Medicine Louisville KY40202 United States

AIm： To investigate the expression of cyclooxygenase-2 （cOX-2） and epithelial growth factor receptor （EGFR） throughout the progression of Barrett＇s esophagus （BE）. mETHODS： cOX-2 and EGFR protein expressions were detected by using immunohistochemical method. A detailed cytomorphological changes were determined. Areas of cOX-2 and EGFR expression were quantified by using c.mputer Imaging System. RESULTS： The expressions of both cOX-2 and EGFR increased along with the progression from BE to esophagus adenocarcinoma （EAc）. A positive correlation was found between cOX-2 expression and EGFR expression. cONcLUSION： cOX-2 and EGFR may be cooperative in the stepwise progression from BE to EAc, thereby leading to carcinogenesis.

关键词： cycloxygenase -2 (cOX-2) Epithelial growth factor receptor (EGFR) Barrett's esophagus carcinogenesis

Functional recovery and muscle atrophy in pre-clinical models of peripheral nerve transection and gap-grafting in mice:effects of 4-aminopyridine

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Neural Regeneration Research 2023年第2期18卷 439-444页

作者： Jung Il Lee m A Hassan Talukder Zara Karuman Anagha A.Gurjar Prem Kumar Govindappa Jagadeeshaprasad m.Guddadarangaiah Kristen m.manto Grant D.Wandling john P.Hegarty David L.Waning john c.Elfar Department of Orthopaedics and Rehabilitation Center for Orthopaedic Research and Translational ScienceThe Pennsylvania State University College of MedicineHersheyPAUSA Department of Orthopaedic Surgery Korea University Guro HospitalSeoulSouth Korea Department of cellular and molecular Physiology The Pennsylvania State University College of MedicineHersheyPAUSA

We recently demonstrated a repurposing beneficial effect of 4-aminopyridine(4-AP),a potassium channel blocker,on functional recove ry and muscle atrophy after sciatic nerve crush injury in ***,this effect of 4-AP is unknown in nerve transection,gap,and grafting *** evaluate and c.mpare the functional recovery,nerve morphology,and muscle atrophy,we used a novel stepwise nerve transection with gluing(STG),as well as 7-mm irreparable nerve gap(G-7/0)and 7-mm isografting in 5-mm gap(G-5/7)models in the absence and presence of 4-AP *** surgery,sciatic functional index was determined wee kly to evaluate the direct in vivo global motor functional *** 12 weeks,nerves were processed for whole-mount immunofluorescence imaging,and tibialis anterior muscles were harvested for wet weight and quantitative histomorphological analyses for muscle fiber crosssectional area and minimal Feret's *** post-injury sciatic functional index values in STG and G-5/7 models were significantly greater than those in the G-7/0 model.4-AP did not affect the sciatic functional index recovery in any *** to STG,nerve imaging revealed more misdirected axons and distorted nerve architecture with *** muscle weight,cross-sectional area,and minimal Feret's diameter were significantly smaller in G-7/0 model c.mpared with STG and G-5/7,4-AP treatment significantly increased right TA muscle mass,cross-sectional area,and minimal Feret's diameter in G-7/0 *** findings demonstrate that functional recovery and muscle atrophy after peripheral nerve injury are directly related to the intervening nerve gap,and 4-AP exerts diffe rential effects on functional recove ry and muscle atrophy.

关键词： 4-aminopyridine functional recovery muscle atrophy nerve gap nerve grafting nerve imaging nerve transection

PVDF ultrafiltration membranes of controlled performance via blending PVDF-g-PEGmA copolymer synthesized under different reaction times

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Frontiers of Environmental Science & Engineering 2018年第2期12卷 29-40页

作者： Shuai Wang Tong Li chen chen Baicang Liu john c. crittenden college of Architecture and Environment Sichuan University Chengdu 610207 China Institute of New Energy and Low carbon Technology Sichuan University Chengdu 610207 China Research center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Litree Purifying Technology co. Ltd Haikou 571126 China Brook Byers Institute for Sustainable Systems School of Civil and Environmental Engineering Georgia Institute of Technology Atlanta GA 30332 USA

Polyvinylidene fluoride grafted with poly（ethylene glycol） methyl ether methacrylate （PVDF-g- PEGmA） was synthesized using atomic transfer radical polymerization （ATRP） at different reaction times （9 h, 19 h, and 29 h）. The corresponding conversion rates were 10%, 20% and 30%, respectively. PVDF was blended with the copolymer mixtnre containing PVDF-g-PEGmA, solvent and residual PEGmA under different reaction times. In this study, we explored the effect of the copolymer mixture additives with different synthesis times on cast membrane performance. Increasing the reaction time of PVDF-g-PEGmA causes more PVDF-g-PEGmA and less residual PEGmA to be found in the casting solution. Incremental PVDF-g-PEGmA can dramatically increase the viscosity of the casting solution. An overly high viscosity led to a delayed phase inversion, thus hindering PEGmA segments in PVDF- g-PEGmA from migrating to the membrane surface. However, more residual PEGmA contributed to helping rnore PEGmA segments migrate to the membrane surface. The pure water fluxes of the blended membrane with reaction times of 9 h, 19 h, and 29 h are 5445 L. m 2.h I 1068 L- m 2.h land 1179 L.m 2.h I respectively, at 0.07 mPa. Delayed phase inversion can form smaller surface pore size distributions, thus decreasing the water flux for the membranes with PVDF-g-PEGmA at 19 h and 29 h. Therefore, we can control the membrane pore size distribution by decreasing the reaction time of PVDF-g-PEGmA to obtain a better flux performance. The membrane with PVDF-g-PEGmA at 19 h exhibits the best foulant rejection and cleaning recovery due to its narrow pore size distribution and high surface oxygen content.

关键词： Polyvinylidene fluoride ultrafiltvation mem-braneAmphiphilic copolymerBlended modificationHigh fluxAtomic transfer radical polymerization