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Journal of Environmental Protection 2011年第9期2卷 1227-1239页

作者： Richard K. Appoh Louis k. Doamek.or Ebenezer k. Hayford Raphael k. k.ak. Vincent k. Nartey 不详

Artisanal gold mining in local communities is on the increase. This has led to concerns about mercury pollution resulting from these mining activities. This study was conducted to assess the level of mercury pollution in rivers and streams around artisanal gold mining areas of the Birim North District of Ghana. Rivers, streams, sediments and boreholes were sampled to determine total mercury levels during the wet and dry seasons and to explore the potential impact of the mercury levels on water quality in the area. The results show that the total mercury concentrations measured upstream were significantly lower than concentrations in samples tak.n downstream. Also, the total mercury concentrations measured in the stream water samples in both seasons exceeded the WHO guideline limit (1.0 μg/L) for drink.ng water. However, one downstream total mercury concentration exceeded the guideline limit in the dry season. The total mercury concentrations in sediments upstream and downstream in both seasons exceeded the US-EPA guideline value of 0.2 mg/k.. The boreholes in the study area have total mercury concentrations exceeding the WHO guideline limit during both seasons. Total mercury concentrations in the boreholes in the wet season were lower than the dry season.

关键词： Mercury Pollution Artisanal Gold mining Birim North District Ghana

Lamellar k.ratoplasty with corneoscleral graft for limbal dermoids

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International Journal of Ophthalmology(English edition) 2018年第3期11卷 512-515页

作者： Oriel Spierer Daniel Gologorsk. Eldad Adler richard k. Forster Bascom Palmer Eye Institute University of Miami Miller School of Medicine Palm Beach Gardens Florida 33418 USA Department of Ophthalmology E. Wolfson Medical Center Sackler Faculty of Medicine Tel Aviv University Tel Aviv 69978 Israel

To assess the postoperative outcomes of limbal dermoid excision with corneoscleral graft transplantation. The charts of 8 consecutive patients （mean age： 13.0y） who had undergone limbal dermoid excision with lamellar corneosclerai graft transplantation by a single surgeon were retrospectively reviewed. Mean dermoid size was 7.75 mm （6.0-12.0 mm）. Mean visual acuities （in IogMAR units） before and after surgery were 1.8 and 1.7, respectively （P=0.29）. Spherical equivalents were 1.3 diopter （D） before surgery and 0.7 D after surgery （P=0.40）. The mean astigmatism measurements before and after surgery were 2.4 D and 1.5 D, respectively （P=0.17）. Vector analysis revealed a mild change in astigmatism with a mean ＂d＂ of 3,2 （0,56-6.89）, No intra- or post-operative complications occurred. Lamellar k.ratoplasty for limbal dermoids is safe and offers good cosmesis and tectonic stability. A significant decrease in the amount of astigmatism is not expected following surgery.

关键词： limbal dermoid lamellar k.ratoplasty pediatric k.ratoplasty comeoscleral graft astigmatism

The importance of laminin at the blood-brain barrier

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Neural Regeneration Research 2023年第12期18卷 2557-2563页

作者： Sebok.k.Halder Arjun Sapk.ta richard Milner San Diego Biomedical Research Institute San DiegoCAUSA

The blood-brain barrier is a unique property of central nervous system blood vessels that protects sensitive central nervous system cells from potentially harmful blood components.The mechanistic basis of this barrier is found at multiple levels,including the adherens and tight junction proteins that tightly bind adjacent endothelial cells and the influence of neighboring pericytes,microglia,and astrocyte endfeet.In addition,extracellular matrix components of the vascular basement membrane play a critical role in establishing and maintaining blood-brain barrier integrity,not only by providing an adhesive substrate for blood-brain barrier cells to adhere to,but also by providing guidance cues that strongly influence vascular cell behavior.The extracellular matrix protein laminin is one of the most abundant components of the basement membrane,and several lines of evidence suggest that it plays a k.y role in directing blood-brain barrier behavior.In this review,we describe the basic structure of laminin and its receptors,the expression patterns of these molecules in central nervous system blood vessels and how they are altered in disease states,and most importantly,how genetic deletion of different laminin isoforms or their receptors reveals the contribution of these molecules to blood-brain barrier function and integrity.Finally,we discuss some of the important unanswered questions in the field and provide a“to-do”list of some of the critical outstanding experiments.

关键词： astrocytes basement membrane blood vessels blood-brain barrier integrity dystroglycan endothelial cells inflammation integrins laminin pericytes

Cell transplantation to replace retinal ganglion cells faces challenges-the Switchboard Dilemma

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Neural Regeneration Research 2021年第6期16卷 1138-1143页

作者： Yuan Liu richard k.Lee Bascom Palmer Eye Institute University of Miami Miller School of MedicineMiamiFLUSA

The mammalian retina displays incomplete intrinsic regenerative capacities;therefore,retina degeneration is a major cause of irreversible blindness such as glaucoma,agerelated macular degeneration and diabetic retinopathy.These diseases lead to the loss of retinal cells and serious vision loss in the late stage.Stem cell transplantation is a great promising novel treatment for these incurable retinal degenerative diseases and represents an exciting area of regenerative neurotherapy.Several suitable stem cell sources for transplantation including human embryonic stem cells,induced pluripotent stem cells and adult stem cells have been identified as promising target populations.However,the retina is an elegant neuronal complex composed of various types of cells with different functions.The replacement of these different types of cells by transplantation should be addressed separately.So far,retinal pigment epithelium transplantation has achieved the most advanced stage of clinical trials,while transplantation of retinal neurons such as retinal ganglion cells and photoreceptors has been mostly studied in pre-clinical animal models.In this review,we opine on the k.y problems that need to be addressed before stem cells transplantation,especially for replacing injured retinal ganglion cells,may be used practically for treatment.A k.y problem we have called the Switchboard Dilemma is a major block.to have functional retinal ganglion cell replacement.We use the public switchboard telephone network.as an example to illustrate different difficulties for replacing damaged components in the retina that allow for visual signaling.Retinal ganglion cell transplantation is confronted by significant hurdles,because retinal ganglion cells receive signals from different interneurons,integrate and send signals to the correct targets of the visual system,which functions similar to the switchboard in a telephone network.therefore the Switchboard Dilemma.

关键词： cell transplantation optic nerve regeneration photoreceptors retina degeneration retinal ganglion cells stem cells

Generalization of predator recognition:Velvet geck.s display anti-predator behaviours in response to chemicals from non-dangerous elapid snak.s

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Current Zoology 2010年第3期56卷 337-342页

作者： Jonathan k. WEBB Weiguo DU David PIk. richard SHINE School of Biological Sciences University of Sydney NSW 2006 Australia Department of Environmental Sciences School of Life Sciences Hangzhou Normal College 310036 Hangzhou Zhejiang China

Many prey species detect chemical cues from predators and modify their behaviours in ways that reduce their risk.ofpredation. Theory predicts that prey should modify their anti-predator responses according to the degree of threat posed by thepredator. That is, prey should show the strongest responses to chemicals of highly dangerous prey, but should ignore or respondweak.y to chemicals from non-dangerous predators. However, if anti-predator behaviours are not costly, and predators are rarelyencountered, prey may exhibit generalised antipredator behaviours to dangerous and non-dangerous predators. In Australia, mostelapid snak.s eat lizards, and are therefore potentially dangerous to lizard prey. Recently, we found that the nocturnal velvetgeck. Oedura lesueurii responds to chemicals from dangerous and non-dangerous elapid snak.s, suggesting that it displays generalisedanti-predator behaviours to chemicals from elapid snak.s. To explore the generality of this result, we videotaped the behaviourof velvet geck.s in the presence of chemical cues from two small elapid snak.s that rarely consume geck.s: the nocturnalgolden-crowned snak. Cacophis squamulosus and the diurnal marsh snak. Hemiaspis signata. We also videotaped geck.s in trialsinvolving unscented cards (controls) and cologne-scented cards (pungency controls). In trials involving Cacophis and Hemiaspischemicals, 50% and 63% of geck.s spent long time periods (> 3 min) freezing whilst pressed flat against the substrate, respectively.Over half the geck.s tested exhibited anti-predator behaviours (tail waving, tail vibration, running) in response to Cacophis(67%) or Hemiaspis (63%) chemicals. These behaviours were not observed in control or pungency control trials. Our resultssupport the idea that the velvet geck. displays generalised anti-predator responses to chemical cues from elapid snak.s.Generalised responses to predator chemicals may be common in prey species that co-occur with multiple, ecologically similar,dangerous predators [Current Zoology 56 (3): 337

关键词： Predation risk Chemical cues Lizard Elapidae Gek.onidae Olfaction Multipredator

Analyzing biases of nitrogen contents and δ^(15)N values arising from acidified marine sediments with different CaCO_3 concentrations

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Acta Oceanologica Sinica 2018年第8期37卷 1-5页

作者： PENG Yajun LIU Dongyan WANG Yujue richard Pierre k.ESING John k. k.y Laboratory of Coastal Zone Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone Research Chinese Academy of Sciences School of Management Science Guizhou University of Finance and Economics State k.y Laboratory of Estuarine and Coastal Research East China Normal University Littoral Environment et Sociétés UMR 7266 CNRS-Université de La Rochelle CSIRO Oceans and Atmosphere and University of Western Australia Oceans Institute Indian Ocean Marine Research Centre

In some studies, the researchers pretreated and measured organic carbon, nitrogen and their isotopes（δ^（13）C and δ^（15）N） of marine sediment together, to save costs and resources of analysis. However, the procedure of acidification to remove inorganic carbon for analysing δ^（13）C can affect the values of nitrogen and δ^（15）N, and the biases vary a lot depending on the CaCO_3 contents of sediments. In this study, the biases of total nitrogen（TN）and δ^（15）N values arising from acidified sediments were compared between the CaCO_3-poor（1%–16%） and CaCO_3-rich（20%–40%） samples. TN and δ^（15）N values were altered during acid treatment（without centrifugation） that possibly led to N-containing compounds volatilization. For CaCO_3-poor samples, acidification led to a range of 0%–40% TN losses and 0‰–2‰ shift in δ^（15）N values; and 10%–60% TN losses and 1‰–14‰ shift in δ^（15）N values for CaCO_3-rich samples. The biases from most samples exceeded the precision of the instrument（0.002% for TN and 0.08‰ for δ^（15）N）, and high biases could mislead our judgment for the environmental implication of the data. Thus,avoiding co-analysis of organic carbon, nitrogen and their isotopes（δ^（13）C and δ^（15）N） in sediments, even for CaCO_3-poor marine sediments, is necessary.

关键词： stable isotope nitrogen nitrogen CaCO3 acidification marine sediment

Familiarity with a female does not affect a male＇s courtship intensity in garter snak.s Thamnophis sirtalis parietalis

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Current Zoology 2012年第6期58卷 805-811页

作者： richard SHINE Jonathan k. WEBB Amanda LANE Robert T. MASON School of Biological Sciences A08 University of Sydney NSW 2006 Australia Department of Zoology Oregon State University Cordley Hall 3029 Corvallis Oregon 97331-2914 USA

Abstract In many animal species, males direct more intense courtship towards females they have not previously encountered, than towards females with which they have previously mated. To test the factors responsible for this "Coolidge Effect", we need studies on a wide range of taxa - including those with mating systems in which we would not expect (based on current theory) that such an effect would be evident. The Coolidge Effect has been documented in several lizard species, but has not been look.d for (and would not be expected) in snak.s. We conducted experimental trials with red-sided garter snak.s Thamnophis sirtalis parietalis at a communal den in Manitoba, to see whether previous exposure to a female (either courting, or courting plus mating) modified male mate choice or courtship intensity. In k.eping with prediction from theory (but contrary to an early anecdotal report), male garter snak.s did not modify their courtship behaviour based upon their familiarity (or lack.thereof) with a specific female. At least in large courting aggregations, male snak.s may maximize their fitness by basing mate-choice upon immediate attributes of the female (body size, condition, mated status) and the intensity of competition (numbers and sizes of rival males) rather than information derived from previous sexual encounters .

关键词：女性男性强度蛇交配系统动物物种竞争对手求爱行为

Heat,sight and scent:multiple cues influence foraging site selection by an ambush-foraging snak. Hoplocephalus bungaroides(Elapidae)

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Current Zoology 2009年第4期55卷 266-271页

作者： Weiguo DU Jonathan k. WEBB richard SHINE Department of Biological Sciences University of Sydney NSW 2006 Australia Hangzhou k.y Laboratory for Animal Science and Technology College of Life and Environmental Sciences Hangzhou NormalUniversity Hangzhou 310036 China

Most mobile organisms respond to multiple cues when selecting habitat types,and laboratory experiments that manipulate only single cues may fail to reveal the true complexity of habitat-selection behaviour.In south-eastern Australia,broad-headed snak.s Hoplocephalus bungaroides(Elapidae)lie in wait under sun-warmed rock. to ambush velvet geck.s Oedura leseuerii(Gek.onidae).Previous laboratory work.has shown that both the geck.s and the snak.s actively select hotter rather than colder rock.,and that the snak.s actively select rock. scented by geck.s.We manipulated rock.temperature and the presence of two types of cues from geck.s(chemical and visual information)to clarify the causal basis for foraging site selection by the juveniles of this snak..When given a choice between cold lizard-scented rock. and hot unscented rock.,our captive snak.s gave a higher priority to lizard scent than to temperature.The snak.s also selected shelter-sites that provided visual as well as scent cues from lizards,rather than shelter-sites with scent cues alone.Thus,although broad-headed snak.s show a direct preference for hotter rather than colder rock. in the laboratory,their choice of foraging site in the field may also be influenced by the presence of scent cues from prey.Our laboratory results suggest that habitat selection by broad-headed snak.s may be more complex than has been suggested by previous single-factor laboratory trials.

关键词：蛇草料习性动物学

The role of monocytes in optic nerve injury

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Neural Regeneration Research 2023年第8期18卷 1666-1671页

作者： Xiangxiang Liu Yuan Liu Mohamed M.k.odeiry richard k.Lee Beijing Tongren Eye Center Beijing Tongren HospitalCapital Medical UniversityBeijingChina Bascom Palmer Eye Institute Department of OphthalmologyUniversity of Miami Miller School of MedicineMiamiFLUSA

Monocytes,including monocyte-derived macrophages and resident microglia,mediate many phases of optic nerve injury pathogenesis.Resident microglia respond first,followed by infiltrating macrophages which regulate neuronal inflammation,cell proliferation and differentiation,scar formation and tissue remodeling following optic nerve injury.However,microglia and macrophages have distinct functions which can be either beneficial or detrimental to the optic nerve depending on the spatial context and temporal sequence of their activity.These divergent effects are attributed to pro-and anti-inflammatory cytok.nes expressed by monocytes,crosstalk.between monocyte and glial cells and even microglia-macrophage communication.In this review,we describe the dynamics and functions of microglia and macrophages in neuronal inflammation and regeneration following optic nerve injury,and their possible role as therapeutic targets for axonal regeneration.

关键词： fibrotic scar glial scar inflammation macrophage microglia optic nerve injury regeneration

无缝合非灼烧式输精管上皮刮除术：人类实验性研究

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Asian Journal of Andrology 2010年第3期12卷 315-321,I0008页

作者： John k. Amory John W. Jessen Charles Muller richard E. Berger Department of Medicine Center for Research in Reproduction and Contraception University of Washington School of Medicine Seattle WA 98195 USA private Practice Dentistry Seattle WA 98195 USA Department of Urology University of Washington School of Medicine Seattle WA 98195 USA

输精管上皮刮除术可能是一种安全有效的男性绝育方法。本实验探究了输精管上皮刮除术实现绝育的有效性。实验中我们使用了一种称为Vas—X的新型刮匙，对12名要求绝育的正常男性的输精管上皮进行刮除。手术后连续6个月每月进行一次精液... 详细信息

输精管上皮刮除术可能是一种安全有效的男性绝育方法。本实验探究了输精管上皮刮除术实现绝育的有效性。实验中我们使用了一种称为Vas—X的新型刮匙，对12名要求绝育的正常男性的输精管上皮进行刮除。手术后连续6个月每月进行一次精液分析，同时测量疼痛状况。术后3个月，所有男性的精子浓度均降到20万／毫升以下，其中7名男性精子浓度为0，术后疼痛微弱。最终9名男性实现并保持不育，但术后4到6个月期间，3名男性的精子浓度增加，需要重新行刮除术。输精管显微检查发现这三名男性的精子浓度升高是由输精管再通造成。本实验表明：输精管刮除术可以有效的实现绝育，但是有1／4的手术对象由于输精管再通而不能成功实现绝育。本研究表明，输精管刮除术还不够作为切实可行的绝育手段，还有待于进一步完善。

关键词：男性避孕男性绝育再通精子发生输精管输精管结扎术失败