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Journal of Mountain Science 2016年第6期13卷 1078-1084页

作者： Michal CIACH filip KOWALSKI Department of Forest Biodiversity Institute of Forest Ecology and SilvicultureFaculty of ForestryUniversity of Agricultureal.29 Listopada 4531-425 KrakowPoland

Rocky habitats are regarded as biodiversity hot-spots. Along with high species diversity, diverse ecological relationships can be observed in these habitats. Large groups of bird species use rocks in various ways： as perching/roosting sites, breeding or foraging habitats, information exchange sites, display arenas or as sources of minerals and water. Because of the inaccessibility of these environments, their role and importance to animals has been underestimated. We evaluated the use of rocky habitats by birds in the Tatra Mountains （49°13′n; 19°57′E, Carpathians, central Europe）. Rocky habitats were used by 29 bird species, eight of which used cliffs directly （i.e. for nesting, foraging or resting）. The number of species recorded as using cliffs was correlated with the surface area of the cliff face. A total of 2o forms of rocky habitat use were recorded, in five behavioural categories： vocalization, foraging, perching, flight and nesting. Prevailing behaviours were flying by a rock face, circling above the face, and vocalization on a tree/shrub growing next to a rock. Rocks provide a nesting habitat for specialized petrophilic species and permit the existence of numerous ecological relations between species and habitats. The results of this study show that rocky habitats support the diversity of ecological relationships.

关键词： Bird community Rock Cliff Mountains Alpine species Ecological relationships

Comparative analysis of experimental testing procedures for the elicitation of rescue actions in ants

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Current Zoology 2022年第2期68卷 159-168页

作者： filip TURZA Krzysztof MILER Institute of Environmental Sciences Faculty of BiologyJagiellonian UniversityGronostajowa 7Krakow 30-387Poland Institute of Systematics and Evolution of Animals Polish Academy of SciencesStawkowska 17Krakow 31-016Poland

Rescue behavior is observed when 1 individual provides help to another individual in *** reports of rescue behavior concern ants(Formicidae),in which workers rescue each other from various types of *** of these entrapment situations can be simulated in the laboratory using an entrapment bioassay,in which ants confront a single endangered nest mate entrapped on a sandy arena by means of an artificial ***,we compared numerous characteristics of rescue actions(contact between individuals,digging around the entrapped individual,pulling at its body parts,transport of the sand covering it,and biting the snare entrapping it)in Formica cinerea *** performed entrapment tests in the field and in the laboratory,with the latter under varying conditions in terms of the number of ants potentially engaged in rescue actions and the arena substrate(marked or unmarked by ants'pheromones).Rescue actions were more probable and pronounced in the field than in the laboratory,regardless of the type of ***,different test types in the laboratory yielded inconsistent results and showed noteworthy variability depending on the tested characteristic of *** results illustrate the specifics of ant rescue actions elicited in the natural setting,which is especially important considering the scarcity of field ***,our results underline the challenges related to the comparison of results from different types of entrapment tests reported in the available ***,our study shows how animal behavior differs in differing experimental setups used to answer the same questions.

关键词： ants animal behavior entrapment bioassay Formica cinerea rescue behavior

Variation of morphological and leaf stoichiometric traits of two endemic species along the elevation gradient of Mount Kenya, East Africa

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Journal of Plant Ecology 2020年第6期13卷 785-792页

作者： Antony n.Waigwa Brian njoroge Mwangi Gituru R.Wahiti fred Omengo Yadong Zhou Qingfeng Wang Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture Wuhan Botanical GardenChinese Academy of SciencesWuhan 430074China University of Chinese Academy of Sciences Beijing 100049China Sino-Africa Joint Research Center(SAJOREC) Jomo Kenyatta University of Agriculture and TechnologyJujaNairobi 00200Kenya Department of Biodiversity Research Kenya Wildlife ServiceNairobi 00100Kenya Center of Conservation Biology Core Botanical GardensChinese Academy of SciencesWuhan 430074China Sino-Africa Joint Research Center(SAJOREC) Chinese Academy of SciencesWuhan 430074China

Aims The aim of this paper is to assess morphological and leaf stoichiometric responses of Dendrosenecio keniensis and Lobelia gregoriana to extreme environmental conditions along an elevation gradient in tropical *** In this study,we assessed the variation of the morphological traits,including plant height,leaf area,leaf thickness,leaf dry weight,specific leaf area and the leaf stoichiometry traits nitrogen,carbon and phosphorous of the two endemic species *** and *** further explored the relations of these morphological traits to soil organic carbon,soil total nitrogen,soil phosphorous,annual mean temperature,annual mean precipitation,annual total solar radiation,water vapor pressure and the topographic variables aspect,slope and hill shade along the elevation *** 10 m×10 m sampling plots were set up along the elevation gradient ranging from 3500 to 4300 *** used 1 km×1 km grid cells to rasterize our study area in ArcGIS 10.5 for easy access to data pertaining to the climate of each elevation *** performed linear regression of the morphological and leaf stoichiometric traits with elevation as explanatory *** conducted correlation analysis on the morphological and leaf stoichiometric traits with climatic,soil and topographic variables along the elevation *** Findings Dendrosenecio keniensis had wool-like pubescent leaves while *** had mucilage packed succulent and waxy cuticle leaves to avoid *** species exhibited reduced metabolic rates as shown by the low leaf phosphorous *** results also showed that changes in morphology and leaf stoichiometry were determined by a combination of climate,soil and topographic variables that change along elevation on Mount *** observed variations in the morphological and leaf stoichiometric traits of *** and ***,which grow side by side along the elevation gradient,were interpreted as adaptation to the harsh en

关键词： Africa elevation gradient functional traits adaptability climate change

Modeling neuropsychiatric disorders using human induced pluripotent stem cells

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Protein & Cell 2020年第1期11卷 45-59页

作者： Meiyan Wang Lei Zhang fred H.Gage Laboratory of Genetics The Salk Institute for Biological Studies10010 N.Torrey Pines RdLa JollaCA 92037USA neurobiology Section Division of Biological SciencesUniversity of California San DiegoLa JollaCA 92093USA

neuropsychiatric disorders are complex disorders characterized by heterogeneous genetic variations,variable symptoms,and widespread changes in anatomical *** the context of neuropsychiatric disorders,limited access to relevant tissue types presents challenges for understanding disease etiology and developing effective *** pluripotent stem cells(iPSCs)reprogrammed from patient somatic cells offer an opportunity to recapitulate disease development in relevant cell types,and they provide novel approaches for understanding disease mechanisms and for development of effective *** we review recent progress and challenges in differentiation paradigms for generating disease-relevant cells and recent studies of neuropsychiatric disorders using human pluripotent stem cell(hPSC)models where cellular phenotypes linked to disease have been *** use of iPSC-based disease models holds great promise for understanding disease mechanisms and supporting discovery of effective treatments.

关键词： neuropsychiatric disorders iPSCs brain organoid schizophrenia autism spectrum disorder bipolar disorder

Sources, distribution, and risk assessment of organochlorine pesticides in nairobi City, Kenya

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Journal of Environmental Sciences 2020年第10期32卷 178-185页

作者： fred Ayodi Lisouza P.Okinda Owuor Joseph O.Lalah Department of Pure and Applied Chemistry Masinde Muliro UniversityP.O.Box 190Kakamega 50100Kenya Department of Chemistry Maseno UniversityP.O.Box 333Maseno 40105Kenya Department of Geochemistry&Enuironmental Chemistry Technical Uniuersity of KenyaP.O.Box 52428-00200NairobiKerya

The distribution and sources of organochlorine pesticides (OCPs) in air and surface waters were monitored in nairobi City using triolein-filled semipermeable membrane devices (SP-MDs).The SPMDs were extracted by dialysis using n-hexane,followed by cleanup by adsorption chromatography on silica gel *** analysis was done by GC-ECD and confirmed by GC–*** of means was achieved by analysis of variance,followed by pair-wise comparison using the t-test (p≤0.05).The total OCPs ranged between 0.018–1.277 ng/m^3 in the air andKibera>Industrial Area>City Square>ngong’***,these were lower than the USEPA acceptable risks,10^(-6)–10^(-4).This study concluded that atmospheric OCPs did not pose significant cancer risks to the residents.

关键词： Organochlorine pesticides(OCPs) Passive sampling Water-air fugacity ratio Sources and distribution Risk assessment

Structural and functional aspects of the liver and liver sinusoidal cells in relation to colon carcinoma metastasis

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World Journal of Gastroenterology 2005年第33期11卷 5095-5102页

作者： Katrien Vekemans filip Braet Centre of Experimental Surgery and Anaesthesia Abdominal Transplant Surgery Department Catholic University of Leuven (KUL)Herestraat 49 3000 Leuven Belgium Australian Key Centre for Microscopy and Microanalysis Electron Microscopy Unit The University of SydneySydney 2006NSWAustralia

nowadays, liver metastasis remains difficult to cure. When tumor cells escape and arrive in the liver sinusoids, they encounter the local defense mechanism specific to the liver. The sinusoidal cells have been widely described in physiologic conditions and in relation to metastasis during the past 30 years. This paper provides an “overview” of how these cells function in health and in diseases such as

关键词： Metastasis Liver Colon carcinoma Sinusoidalcells Kupffer cells Liver sinusoidal endothelial cells Hepatic nK cells

Identifying nonpoint Sources of Phosphorus and nitrogen: A Case Study of Pollution That Enters a Freshwater Wetland (Laguna Cartagena, Puerto Rico)

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Journal of Water Resource and Protection 2021年第8期13卷 588-604页

作者： Yashira Marie Sánchez-Colón fred Charles Schaffner Public Health Program Ponce Health Sciences University Ponce Puerto Rico School of Science and Technology Ana G. Méndez University Gurabo Puerto Rico

Point and nonpoint sources of phosphorus (P) and nitrogen (n) can cause reductions in water quality, including eutrophication. nonpoint pollution represents a special challenge because of dispersed not easily identifiable sources such as the runoff from soil, nutrients, and other chemicals from agricultural fields and residential areas. Laguna Cartagena is a tropical freshwater wetland, situated in southwestern Puerto Rico. It is a eutrophic ecosystem, and its eutrophication is caused by both external nutrient loading and internal, mainly by phosphorus. This wetland has been affected by phosphorus loading from inorganic agricultural fertilizer in this historically oligotrophic wetland system until the end of subsidized fertilizer use and sugar cane cultivation in the late 1990s. This study identifies: 1) nonpoint sources of phosphorus (SRP, Soluble Reactive Phosphorus and TP, Total Phosphorus) and nitrogen (nitrate, nitrite, and ammonia) that enter Laguna Cartagena;and 2) the role of precipitation events on the contributions of phosphorus and nitrogen loading to ecosystems. Herein we assess water samples from five channelized external sources of P and n that enter Laguna Cartagena at two-week intervals from October 2013 through november 2014. Rainfall data were obtained weekly from a rain gauge. Standard methods were used for all chemical analyses. Results showed that the channelized waterways that carry water to the lagoon can be classified as hypereutrophic (>100 μg/L) for TP concentrations and oligotrophic (nitrogen concentrations. Currently agriculture (rice and cattle) is the predominant land use at the nearby University of Puerto Rico (UPR) Lajas Agricultural Experiment Substation, the predominant nonpoint source of nutrient pollution (SRP, TP and ammonia) in the principal channelized water sources to the lagoon. Current nutrient loads are likely derived from fertilizers applied to the Substation’s rice fields, and a high density livestock. The

关键词： nonpoint Sources Soluble Reactive Phosphorus Total Phosphorus nitrogen Depleted Eutrophication

Hlder norm Estimate for a Hilbert Transform in Hermitean Clifford Analysis

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Acta Mathematica Sinica,English Series 2012年第11期28卷 2289-2300页

作者： Ricardo ABREU-BLAYA Juan BORY-REYES fred BRACKX Hennie DE SCHEPPER Frank SOMMEn Facultad de Informática y Matemática Universidad de Holguín Departamento de Matemática Universidad de Oriente Clifford Research Group Faculty of Engineering Ghent University Clifford Research Group Faculty of Sciences Ghent University

A Hilbert transform for H61der continuous circulant （2 × 2） matrix functions, on the d- summable （or fractal） boundary F of a Jordan domain Ω in R2n, has recently been introduced within the framework of Hermitean Clifford analysis. The main goal of the present paper is to estimate the HSlder norm of this Hermitean Hilbert transform. The expression for the upper bound of this norm is given in terms of the HSlder exponents, the diameter of F and a specific d-sum （d 〉 d） of the Whitney decomposition of Ω. The result is shown to include the case of a more standard Hilbert transform for domains with left Ahlfors-David regular boundary.

关键词： Hermitean Clifford analysis Hilbert transform fractal geometry

nitric oxide removal by wastewater bacteria in a biotrickling filter

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Journal of Environmental Sciences 2014年第3期26卷 555-565页

作者： Hejingying niu Dennis Y C Leung Chifat Wong Tong Zhang Mayngor Chan fred C C Leung Department of Mechanical Engineering The University of Hong Kong School of Biological Sciences The University of Hong Kong Department of Civil Engineering The University of Hong Kong

nitric oxide （nO） is one of the most important air pollutants in atmosphere mainly emitted from combustion source. A biotriclding filter was designed and operated to remove nO from an air stream using bacteria extracted from the sewage sludge of a municipal sewage treatment plant. To obtain the best operation conditions for the biotrickling filter, orthogonal experiments （L9（34）） were designed. Inlet oxygen concentration was found to be the most significant factor of the biotrickling filter and has a significant negative effect on the system. The optimal conditions of the biotrickling filter occurred at a temperature of 40℃, a pH of 8.0 and a chemical oxygen demand of 165 mg/L in the recycled water with no oxygen in the system. The bacteria sample was detected by DnA sequencing technology and showed 93%-98% similarity to Pseudomonas mendocina. Moreover, a full gene sequencing results indicated the bacterium was a brand new strain and named as P. mendocina DLHK. This strain can transfer nitrate to organic nitrogen. The result suggested the assimilation nitrogen process in this system. Through the isotope experimental analysis, two intermediate products （^15nO and ^15n2O） were found. The results indicated the denitrification function and capability of the biotrickling filter in removing nO.

关键词： nO reduction biotrickling filter orthogonal experiment Pseudomonas mendocina isotope labeling

Evaluation of Surface Water Availability for Inland Valleys Rice Production： The Case of Mankran Watershed in a Deciduous Forest Zone of Ghana

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Journal of Environmental Science and Engineering(B) 2012年第2期1卷 250-259页

作者： Busia n. Dawuni Regassa namara fred Kizito Hideto Fujii Ghana Irrigation Development Authority Accra Ghana International Water Management Institute Accra Ghana Japan International Cooperation Centre for Agricultural Sciences （J1RCAS） lbaraki 305-8686 Japan

In Ghana, inland valleys have been found to be suitable for rice cultivation and could potentially increase lowland paddy rice production, This study estimated the temporal variations of surface water resources and their spatial distribution in the Mankran watershed of Ghana through the collection of recorded hydrological data in the bench mark watershedfrom2008 to 2010. Since most inland valley rice cultivation highly depends on rainfall, the watershed precipitation data over a decadal period showed sufficient wet years with a potential to sustain a high cultivation of paddy rice. Peak wetness occurred in June and October over a bi-modal precipitation pattern. Rating curve data for the Mankran-kesse river-upstream depicted low discharge values despite having a higher stream order. Thus stream order alone was not sufficient to estimate water resources potential. It was presumed that the geomorphology and lithology of the highly porous river bed and the presence of high sub-surface water resources stored in this zone may be implicated for this observation. Provision of water storage options for zones like Kesse-upstream seems a feasible option in order to cater for supplementary irrigation while indirectly tapping on subsurface water resources stored in the porous aquifers through basin interflows. Base flow data also showed that the discharge from upstream locations to the downstream exit of the watershed was high through direct surface river discharge and subsurface interflow. The temporal patterns of the hydrology indicate that annual paddy rice cultivation is ideal between May and October.

关键词： Mankran watershed inland valleys surface water availability rice production.