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Three-dimensional light structure of an upland Quercus stand post-tornado disturbance

Journal of Forestry Research 2020年第1期31卷 141-153页

作者： Kevin G.Willson lauren e.cox Justin L.Hart Daniel C.Dey Department of Geography University of AlabamaTuscaloosaAL 35487USA Department of environmental Science Policyand ManagementUniversity of CaliforniaBerkeleyCA 94720USA Northern Research Station USDA Forest ServiceColumbiaMO 65211USA

Light is the most common limiting factor in forest plant communities,influencing species composition,stand structure,and stand productivity in closed canopy *** vertical light structure is relatively simple under a closed canopy because most light is captured by overstory ***,wind disturbance events create canopy openings from local to landscape scales that increase understory light intensity and vertical light structural *** studied the effects of an eF-1 tornado on horizontal and vertical(***-dimensional)light structure within a Quercus stand to determine how light structure changed with increasing disturbance *** used a two-tiered method to collect photosynthetic photon flux density at 4.67 m and 1.37 m above the forest floor to construct three-dimensional light structure across a canopy disturbance severity gradient to see if light intensity varied with increasing tornado *** indicate that increased canopy disturbance closer to the tornado track increased light penetration and light structure heterogeneity at lower forest *** light intensity correlated with increased sapling density that was more randomly distributed across the plot and had shifted light capture higher in the stand *** penetration through the overstory was most strongly correlated with decreased stem density in the two most important tree species(based on relative dominance and relative density)in the stand,Quercus alba L.(r=-0.31)and Ostrya virginiana(Mill.)***(r=-0.27,ped that understory light penetration was most affected by these two *** managers are increasingly interested in patterning silvicultural entries on natural disturbances,they must understand residual stand and light structures that occur after natural disturbance *** providing spatial light data that quantifies light structure post-disturbance,managers can use these results to improve planning required for long-term man

关键词： Photosynthetic photon flux density Midstory Blowdown Heterogeneity

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Supplementation of oligosaccharide-based polymer enhanced growth and disease resistance of weaned pigs by modulating intestinal integrity and systemic immunity

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Journal of Animal Science and Biotechnology 2022年第3期13卷 802-815页

作者： Kwangwook Kim Yijie He Cynthia Jinno lauren Kovanda Xunde Li David Bravo eric cox Yanhong Liu Department of Animal Science University of CaliforniaDavisCA 95616USA School of Veterinary Medicine University of CaliforniaDavisCA 95616USA Pancosma ADM 1180 RolleSwitzerland Department of Virology Parasitology and ImmunologyGhent University9000 GhentBelgium

Background:There is a great demand for antibiotic alternatives to maintain animal health and *** objective of this experiment was to determine the efficacy of dietary supplementation of a blood group A6 type 1antigen oligosaccharides-based polymer(Coligo)on growth performance,diarrhea severity,intestinal health,and systemic immunity of weaned pigs experimentally infected with an enterotoxigenic escherichia coli(eTeC),when compared with ***:Pigs in antibiotic carbadox or Coligo treatment groups had greater(Peight on d 5 or d 11post-inoculation(PI)than pigs in the control group,*** of antibiotics or Coligo enhanced(Peed efficiency from d 0 to 5 PI and reduced(Pequency of diarrhea throughout the experiment,compared with pigs in the control *** of antibiotics reduced(Pecalβ-hemolytic coliforms on d 2,5,and 8 *** in antibiotics or Coligo groups had reduced(Peutrophil counts and serum haptoglobin concentration compared to pigs in the control group on d 2 and 5 *** in Coligo had reduced(Pesenteric lymph nodes on d 5 and 11 PI,whereas pigs in antibiotics or Coligo groups had reduced(Peen on d 11 PI compared with pigs in the control *** d 5 PI,pigs in the Coligo group had greater(Pene expression of ZO1 in jejunal mucosa,but less(Pexpression of IL1B,IL6,and TNF in ileal mucosa,in comparison with pigs in the control *** of antibiotics enhanced(Pe gene expression of OCLN in jejunal mucosa but decreased(Pene expression in ileal mucosa,compared with the *** d 11 PI,supplementation of antibiotics or Coligo up-regulated(Pene expression of CLDN1 in jejunal mucosa,but Coligo reduced(Pene expression in ileal mucosa compared to pigs in the control ***:Supplementation of Coligo improved growth performance,al

关键词： enterotoxigenic e.coli Growth rate Intestinal barrier function Oligosaccharide-based polymer Systemic immunity Weaned pigs

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Sex,size,and prey caloric value affect diet specialization and consumption of an invasive prey by a native predator

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Current Zoology 2019年第5期65卷 499-507页

作者： lauren e.HOSTeRT lauren M.PINTOR James e.BYeRS School of environment and Natural Resources The Ohio State UniversityColumbusOHUSA Odum School of ecology University of GeorgiaAthensGAUSA

escaping the control of natural enemies is thought to heavily influence the establishment success and impact of non-native ***,we examined how the profitability of alternative prey in combination with the presence of a competitor and predator aggressive behavior explain individual differences in diet specialization and the consumption of the invasive green porcelain crab Petrolisthes armatus by the native mud crab predator Panopeus *** from bomb calorimetry estimates show that invasive *** has high caloric value relative to alternative native *** assays indicated that specialization and consumption of invasive *** was mostly exhibited by large,female ***,but the presence of a competitor and predator aggressiveness did not influence diet and the consumption of ***,intrinsic factors(e.g.,sex and body size)seem to explain consumption of *** ar\6 dietary specialization in ***,more *** there are still many predator individuals that do not consume ***,the proportion of individuals that have begun to specialize on *** suggests that for some,it has become more profitable relative to alternative native *** the high caloric value of ***,we suggest that it is likely that differences in the cost of its consumption,including attack,capture,and handling times relative to alternative prey,determine its net profitability to individual predators.

关键词： diet breadth optimal foraging theory enemy escape hypothesis competition aggressive behavior

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Phenotypic plasticity is maintained despite geographical isolation in an African cichlid fish,Pseudocrenilabrus multicolor

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Integrative Zoology 2014年第1期9卷 85-96页

作者： Kirsten e.WIeNS erika CRISPO lauren J.CHAPMAN Department of Pathology New York University School of MedicineNew YorkNYUSA Department of Biology and Health Sciences Pace UniversityNew YorkNYUSA Department of Biology McGill UniversityMontrealQuebecCanada Wildlife Conservation Society BronxNew YorkUSA

Gene flow among populations in different selective environments should favor the evolution of phenotypic plasticity over local *** in development is a common response to long-term hypoxia in some widespread African fishes,including Pseudocrenilabrus multicolor,a cichlid that exploits both normoxic(high oxygen)rivers/lakes and hypoxic(low oxygen)*** studies have shown that fish from normoxic and hypoxic sites differ in many traits,including gill size,brain size and body shape,and that much of this vari-ation reflects developmental ***,these earlier studies focused on areas in Uganda where gene flow between swamp and river or lake populations is *** this study we tested the hypothesis that ***-color from a relatively isolated lake population(Lake Saka,Uganda)exhibit low levels of plasticity in traits re-lated to oxygen *** broods of *** from Lake Saka were reared under low and high dis-solved oxygen,and traits related to gill size,brain mass and body shape were ***,both gill size and brain mass showed high levels of developmental *** suggest that high levels of plasticity,particularly in the gill size of ***,reflects low costs of maintaining the plastic response,even in rela-tively isolated populations.

关键词： brain geometric morphometrics gills hypoxia riverine fish

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Tumor necrosis factor alpha inhibits in vitro bovine embryo development through a prostaglandin mediated mechanism

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Journal of Animal Science and Biotechnology 2012年第1期3卷 21-24页

作者： lauren R Jackson Char e Farin Scott Whisnant Department of Animal Science North Carolina State University PO Box 7621 Raleigh NC 27695-7621 USA

Mastitis or other infectious diseases have been related to reduced fertility in cattle. Inflammatory cytokines such as tumor necrosis factor α （TNFα are released in response to infection and may have negative effects on embryo development, in the current study the effect of exposure to TNFα on the development of in vitro fertilized bovine embryos was examined. Indomethacin, a prostaglandin synthesis inhibitor, was used to determine if blockade of prostaglandin synthesis would alter the effects of TNFα Ovaries were obtained from a local abattoir and immature COC were isolated from 2-10 mm follicles, in vitro matured and fertilized. After fertilization, groups of presumptive zygotes were randomly placed into either control development medium, medium containing 25 ng/mL TNFα or medium containing 25 ng/mL TNFα plus 1 μg/mL indomethacin. The proportion of blastocysts formed was assessed at day 7 of culture. Fewer embryos exposed to TNFα alone reached the blastocyst stage （17.5 ± 2.4%, P 〈 0.01） compared with controls （30.5 ± 2.4%） or embryos developed in TNFα plus indomethacin （25.8 ± 2.8%）. There was no difference between control embryos and embryos developed in TNFα plus indomethacin. These results indicate that TNFα is inhibitory to the in vitro development of bovine embryos and that this inhibition may be mediated by prostaglandins because it can be blocked by indomethacin.

关键词： tumor necrosis factor o bovine embryo indomethacin

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Legacy earthen berms influence vegetation and hydrologic complexity in the Altar Valley,Arizona

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International Soil and Water Conservation Research 2023年第4期11卷 755-763页

作者： Mary H.Nichols Sara e.Duke Chandra Holifield Collins lauren Thompson Southwest Watershed Research Center USDA-ARS2000 E.Allen Rd.TucsonAZ85719USA Southern Plains Area Research Center USDA-ARSSPARCCollege StationTX77845USA University of Arizona College of Science GraduateTucsonAZ85719USA

Across the American Southwest water development has played a critical role in managing *** berms have been constructed throughout US rangelands to manage runoff and reduce *** berms altered runoff patterns to increase soil moisture with positive local vegetative ***,altered runoff patterns can be considered a disturbance that affects broader scale vegetation *** hypothesized that the hydrologic impacts of earthen berms in semiarid rangelands will be reflected in contrasting upslope and downslope vegetation patterns.A supervised classification of grass,shrubs,and bare soil was performed using orthographic imagery taken in June 2016 to quantify the effects of 181 earthen berms in the uplands and floodplain of the Altar Valley in Southern Arizona,*** berms blocked runoff,creating downslope runoff"shadows"within which the precipitation is the dominant water *** documented more bare soil downslope of intact berms in comparison with *** and shrub cover affected by berms were related to soil *** and shrub cover were not different above and below intact berms on fine textured soils,but on sites with coarser textured soil,grass cover was lower downslope of *** breaches occurred on coarser textured soils,the up and downslope differences in grass cover *** study points to the role of conservation structures in adding additional complexity to already heterogeneous landscapes by creating patchwork assemblages of vegetation and bare soil proximal to earthen runoff and erosion control berms.

关键词： Legacy conservation structure earthen bank earthen berm Land degradation Rangeland

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Uptake of Cystatin by Melanoma Cells in Culture

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CellBio 2013年第2期2卷 64-69页

作者： lauren Deady James L. cox Department of Biochemistry AT Still University Kirksville USA Department of Biology Truman State University Kirksville USA

The cystatins are a super family of cysteine protease inhibitors which are ubiquitous in their biologic occurrence. Cystatin C, a type II cystatin, is primarily a secreted protein found in most biological fluids. Besides acting as inhibitors of cathepsin, the cystatins have been found to have some non-inhibitor related functions and multiple physiological roles. Much interest has been generated for the cystatins as metastasis “suppressor-like” proteins, as they have been shown to inhibit metastasis for multiple cancer types. The sites and actions of the cystatins related to tumor suppressor actions are still unclear, however. In this work, we have examined the uptake of cystatin by metastatic melanoma cells in culture. Our results indicate cystatin uptake is mediated by a non-canonical endocytotic pathway in B16 murine melanoma cells.

关键词： Cystatin Melanoma endocytosis Fluorescent

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Neural lineage differentiation of human pluripotent stem cells:Advances in disease modeling

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World Journal of Stem Cells 2023年第6期15卷 530-545页

作者： Yuan-Wei Yan eddie S Qian lauren e Woodard Julie Bejoy Waisman Center University of Wisconsin-MadisonMadisonWI 53705United States Nephrology and Hypertension Vanderbilt University Medical CenterNashvilleTN 37232United States Department of Medicine Vanderbilt University Medical CenterNashvilleTN 37232United States Department of Veterans Affairs Tennessee Valley Healthcare SystemNashvilleTN 37232United States Biomedical engineering Vanderbilt UniversityNashvilleTN 37232United States

Brain diseases affect 1 in 6 people *** diseases range from acute neurological conditions such as stroke to chronic neurodegenerative disorders such as Alzheimer’s *** advancements in tissue-engineered brain disease models have overcome many of the different shortcomings associated with the various animal models,tissue culture models,and epidemiologic patient data that are commonly used to study brain *** innovative method by which to model human neurological disease is via the directed differentiation of human pluripotent stem cells(hPSCs)to neural lineages including neurons,astrocytes,and ***-dimensional models such as brain organoids have also been derived from hPSCs,offering more physiological relevance due to their incorporation of various cell *** such,brain organoids can better model the pathophysiology of neural diseases observed in *** this review,we will emphasize recent developments in hPSC-based tissue culture models of neurological disorders and how they are being used to create neural disease models.

关键词： Induced pluripotent stem cells Astrocytes Oligodendrocytes Microglia Brain organoids Assembloids

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effects of historic wildfire and prescribed fire on site occupancy of bats in Shenandoah National Park,Virginia,USA

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Journal of Forestry Research 2020年第4期31卷 1255-1270页

作者： lauren V.Austin Alexander Silvis W.Mark Ford Karen e.Powers Department of Fish and Wildlife Conservation Virginia TechBlacksburgVA 24061USA Resource environmental Solutions WarrentonVA 20187USA U.S.Geological Survey Virginia Cooperative Fish and Wildlife Research UnitBlacksburgVA 24061USA Biology Department Radford UniversityRadfordVA 24141USA

Given the likelihood of regional extirpation of several once-common bat species in eastern North America from white-nose syndrome,it is critical that the impacts of forest management activities,such as prescribed fire,are known in order to minimize potentially additive negative effects on bat *** wildfires may offer a suitable surrogate to assess long-term burn impacts on bats for planning,implementing and assessing burn *** examine the effects of historic fire on bats,we sampled bat activities at 24 transect locations in burned and unburned forest stands in the central Appalachian Mountains of Shenandoah National Park(SNP),Virginia,*** was limited evidence of positive fire effects over time on hoary bats(Lasiurus cinereus Beauvois)and big brown bats(eptesicus fuscus Beauvois)***,there were few or mostly equivocal relationships of bat occupancy relative to burn conditions or time since fire in SNP across species using a false-positive occupancy *** results suggest that fire does not strongly affect bat site occupancy short-or long-term in the central Appalachians.

关键词： Appalachian mountains Bats False-positive occupancy Prescribed fire Wildfire

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Transcatheter Device Closure of a Perimembranous Ventricular Septal Defect in Congenitally Corrected Transposition of the Great Arteries

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Congenital Heart Disease 2022年第2期17卷 193-199页

作者： Catherine e.Tomasulo Lindsay S.Rogers lauren Andrade Michael LO’Byrne Division of Cardiology The Children’s Hospital of PhiladelphiaPhiladelphiaUSA Division of Cardiology Hospital of the University of PennsylvaniaPhiladelphiaUSA Center for Pediatric Clinical effectiveness The Children’s Hospital of PhiladelphiaPhiladelphiaUSA Leonard Davis Institute and Center for Cardiovascular Outcomes Qualityand Evaluative ResearchUniversity of PennsylvaniaPhiladelphiaUSA

The majority of patients with congenitally corrected transposition of the great arteries,also known as transposition of the great arteries{S,L,L}have ventricular septal defects(VSD),most commonly perimembranous VSD(pmVSD).Transcatheter device closure of pmVSD in these patients has not been widely *** present a case of device closure of pmVSD in L-TGA with an Amplatzer Duct Occluder II(ADOII)device using a deployment starting in the subpulmonary left *** case demonstrates some of the technical advantages of the ADOII device for VSD closure,specifically its low profile,symmetric shape,and soft *** characteristics are advantageous in closing conventional pmVSD but are especially useful in patients with challenging anatomic substrates.

关键词： Percutaneous catheterization congenital heart disease thromboembolism

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