Tropic attributes of the mudskipper, Periophthalmus barbarus (Gobiidae: Oxudercinae) in the mangrove swamps of Imo River estuary, Nigeria

Aspects of the trophic attributes of the mudskipper,Periophthalmus barbarus occurring in the mangrove swamps of ImoRiver estuary, Nigeria, were investigated during a 12-month period(April, 1992-March, 1993). Feeding intensity increased with size;it was higher in the dry season (November-April) than in the wetseason (May-October); monthly changes in the indices of feedingintensity were significantly correlated. Major food objectscomprised detritus and benthic algae; crustaceans, insects,macrophyte matter and sand grains were minor food objects whilefish, molluscs, Chilopoda, nematodes and fungi were unconsciouslydevoured objects. Diet varied seasonally; algae and sesarmid crabswere generally more in the dry season than during the rains whereasFPOM and fish increased in the wet over dry season. The mudskipperdisplay a high degree of euryphagy and can be considered as ageneralist and an omnivore. The lower trophic status of P. barbarusqualifies it as a good aquaculture candidate. Food richness washigher in big-sized class (BSC) than small-sized class (SSC).Size-based and seasonal variations were not apparent in foodrichness. Diet breadth was higher in the BSC than the SSC; therewas dry season increase in diet breadth.     

Prenatal diagnosis and molecular cytogenetic characterisation of a small de novo interstitial duplication 16q11.2-q13

We describe the first prenatally detected case of a small de novo interstitial duplication of chromosome 16q. This chromosomal aberration is extremely rare. Amniocentesis was indicated by advanced maternal age only. Ultrasound examinations of the foetus showed no abnormalities. Conventional and molecular cytogenetic analyses on cultured amniocytes by comparative genomic hybridisation (CGH) and fluorescence in situ hybridisation (FISH) using partial chromosome paints and a locus-specific YAC clone revealed a de novo direct duplication of the chromosomal region 16q11.2-q13 leading to a partial trisomy 16q (46,XX,dup(16)(q11.2q13)). There are only five postnatal reports of comparable duplications involving this chromosomal region. These patients presented with little or no associated dysmorphic features but with significant neurodevelopmental delay and severe behavioural problems. After genetic counselling, the parents opted for termination of pregnancy. Post-mortem examination showed slight facial dysmorphic signs, minor dysgenesis of the ovaries and an atypical outflow of the arteria thyroidea ima. Copyright © 2006 John Wiley & Sons, Ltd.     

BiOBr分子印迹材料的制备及其降解诺氟沙星性能

为了有效处理低浓度抗生素残留废水,以水热法制备的BiOBr为载体,诺氟沙星（NOR）为模板,通过表面分子印迹法制备了BiOBr分子印迹材料（MIP）.同时,采用SEM与XRD对制备的材料进行相分析及显微结构分析,并利用XPS、FTIR、BET和UV-Vis DRS对所合成材料的微观结构进行观察.最后,以诺氟沙星（NOR）为目标污染物,对MIP在暗反应下的吸附性能及300 W Xe灯照射下的光催化性能进行测定,并探讨pH、投加量、初始浓度、是否印迹处理对NOR去除的影响.实验结果表明,在pH为中性,MIP投加量为2.5 g·L^-1的条件下,MIP对5 mg·L^-1 NOR溶液的去除率达到96.2%,且对低浓度（1 mg·L^-1）NOR溶液的去除率达到99%.综合表明,本文所制备的MIP适用于低浓度诺氟沙星废水的处理.     

腐植酸中不同分子量组分与As(Ⅲ)的络合性能

采用超滤方法将腐植酸（HA）分成5个不同分子量组分,利用平衡透析法研究HA中不同分子量组分与As（III）的络合特征和作用机理,计算络合过程的条件分配系数、表观稳定常数.结果表明,腐植酸组分的分子量对HA与As（III）的络合过程有显著的影响,当分子量小于10kDa时,HA与As（III）络合能力明显强于其他条件.其中羧基和酚羟基在HA与砷络合中起重要作用,为主要络合位点.采用Scatchard分析和双位点配体模型对络合结果进行拟合,发现HA中不同分子量组分和As（III）的络合过程中均存在强和弱2种络合位点.     

A Spatial Model to Estimate Habitat Fragmentation and Its Consequences on Long-Term Persistence of Animal Populations

The increasing use of the landscape by humans has led to important diminutions of natural surfaces. The remaining patches of wild habitat are small and isolated from each other among a matrix of inhospitable land-uses. This habitat fragmentation, by disabling population movements and stopping their spread to new habitats, is a major threat to the survival of numerous plant and animal species. We developed a general model, adaptable for specific species, capable of identifying suitable habitat patches within fragmented landscapes and investigating the capacity of populations to move between these patches. This approach combines GIS analysis of a landscape, with spatial dynamic modeling. Suitable habitat is identified using a threshold area to perimeter ratio. Potential movement pathways of species between habitat patches are modeled using a cellular automaton. Habitat connectivity is estimated by overlaying habitat patches with movement pathways. The maximum potential population is calculated within and between connected habitat patches and potential risk of inbreeding within meta-populations is considered. The model was tested on a sample map and applied to scenario maps of predicted land-use change in the Peoria Tri-county region (IL). It (1) showed area of natural area alone was insufficient to estimate the consequences on animal populations; (2) underscored the necessity to use approaches investigating the effect of land-use change spatially through the landscape and the importance of considering species-specific life history characteristics; and (3) highlighted the model's potential utility as an indicator of species likelihood to be affected negatively by land-use scenarios and therefore requiring detailed investigation.     

Forest Health Assessment and Monitoring – Issues for Consideration

Part of this paper has been prepared for the lecture Forest Health Assessment-Criteria,Methods and Problems given by the author at the UIMPuniversity course Sanidad Forestal en el Bosques Mediterraneos yTemplados. Implicacion de la Contaminacion Atmosferica y del Cambio Global, held in Valencia, Spain, October, 1995. Assessment and monitoring of forest health representsa key point for environmental policy and for the management ofenvironmental resources. With the renewed interest in assessment andmonitoring of forest health generated by the suspected occurrence ofa widespread forest decline in Europe and North America, manyactivities have been undertaken: however, some questions should beconsidered and clarified when attempting to estimate forest health.Particularly, the objective(s) of the assessment and monitoringprogram should be carefully identified. Identification of a program‘stask has a number of implications and consequences: it implies adefinition of what concept of forest health (forest ecosystem health,forest health or forest trees health?) is assumed, what will be thetarget entity to be monitored, and therefore the identification of therelevant assessment questions and assessment endpoints.Consequences concern the definition of the spatial scale (frominternational to landscape and plot scale monitoring) and ecologicalcoverage (from single species population to population ofecosystems) of the program, which can have a considerable influenceon the choice of the proper sampling strategy and tactic, as well ason the most suitable methods, indicators and indices to be used.Although much of the work in the field of forest health and airpollution has concentrated on surveys on crown transparency anddiscoloration, there is an entire range of methods, indicators andindices developed to assess the health status of forests. The decisionas to which ones should be used will depend on the aim of theprogram and on economic and practical considerations. A furtherconsideration concerns the time span of the program, but anydecision in this field is subject to many limitations due to difficultiesin predicting future monitoring needs. All these points should becarefully considered and implemented according to a rigorousQuality Assurance procedure since any decision will influence futurework for many years.     

阳离子共聚物的反相悬浮聚合

采用反相悬浮聚合方法合成颗粒状的阳离子型高分子絮凝剂。选用丙烯酰胺(Am)和氯化[N,N,N-三甲基乙醇丙烯酸酯]盐(AQ)两种单体,研究反应体系的特征及影响分子量的基本因素,诸如温度、单体浓度、引发剂浓度、分散剂浓度、水相和油相的体积比(Vw/Vo)对分子量的影响。为了选择出最佳原料比,本文对两种单体的原料比进行了研究。实验中还发现亚硫酸钠是一种优良的缩短反应诱导期、加速反应进程的试剂。