FOAM, a new simple benthic degradative module for the LAMP3D model: an application to a Mediterranean fish farm

The modelling framework already introduced by Doglioli, Magaldi, Vezzulli and Tucci to predict the potential impact of a marine fish farm is improved following different directions, namely (1) real historic current-metre data are used to force the simulations, (2) settling velocity values specifically targeting Mediterranean fish species are used, and (3) a new benthic degradative module, the Finite Organic Accumulation Module, is added to the modelling framework. The Finite Organic Accumulation Module uses the output of the other functional units of the modelling framework to calculate the organic load on the seabed. The Finite Organic Accumulation Module considers the natural capability of the seafloor in absorbing part of the organic load. Different remineralization rates reflect the sediment stress level according to the work of Findlay and Watling. Organic degradation for both uneaten feed and faeces is evaluated by changing the release modality (continuous and periodical) and by varying the settling velocities. It is found that the maximum impact on the benthic community is observed either for quickly sinking uneaten feed released twice a day, or for less intense near-bottom current conditions. If both the above-mentioned scenarios coexist, a high stress level is established in the sediment. The model also suggests that the use of self-feeders in cages can reduce farm impacts significantly. These results show how the new and more complete modelling framework presented here is able to improve the objectivity in the decision-making processes and how it may be successfully used for planning and monitoring purposes.     

浓缩风能装置内部流场仿真分析

浓缩风能装置是浓缩风能型风力发电机组的主要部件之一,其结构直接影响机组输出功率的大小。为了提高浓缩风能装置的浓缩效率,以浓缩风能装置为研究对象,应用三维建模软件与CFD(computational fluid dynamics)软件建立了几何模型与网格模型。基于上述模型,提出应用数值模拟方法对浓缩风能装置内部流场进行仿真分析,并通过比较分析不同湍流模型下的内部流场特性,得知标准κ-ω湍流模型更加适用于浓缩风能装置内部流场仿真。基于上述浓缩风能装置模型和湍流模型,分别对不同尺寸参数的浓缩风能装置内部流场特性进行仿真分析,得到了扩散角对浓缩风能装置内部流场特性的影响比收缩角、中央圆筒长度的影响大的规律,此规律为浓缩风能装置结构优化与设计提供了依据,优化后的结构能明显提高风能品质和风电机组输出功率。     

Regulation of amino acid biodegradation in soil as affected by depth

Dissolved organic nitrogen (DON) and in particular free amino acids represent a key pool in the terrestrial soil C and N cycle. The factors controlling the rate of turnover of this pool in soil, however, remain poorly understood. We investigated the factors regulating the rate of amino acid turnover at different depths (up to 1.2 m) in five low-input, acid soil profiles. Within the root zone (0–60 cm), amino acids constituted 8% of the DON and represented only a small fraction of plant available N. In all the soil profiles, the rate of amino acid mineralisation decreased progressively with depth. The average half-life of the exogenously added amino acids in the soil was 5.8 h in topsoils (0–10 cm), falling to 20 h at a depth of 50 cm and to 33 h at 100 cm. Generally, the rate of amino acid mineralisation correlated positively with total soil C and N, soil microbial activity (basal soil respiration rate) and soil content. The relatively rapid rates of microbial amino acid assimilation in subsoils below the root zone (>60 cm) indicate that long-term transport of amino acids (e.g. from soil to freshwaters) will be low. Based upon the C-to-N ratio of the amino acid substrate and the microbial C assimilation efficiency, we estimate that approximately 40–60% of the amino acid-N will be excreted as . In conclusion, the rapid rate of free amino acid turnover and their low concentration in soil solution indicate that the formation of inorganic N ( and ) in soil is limited primarily by the rate of free amino acid appearance in soil and not by the rate of amino acid mineralisation.     

The chemical genomic portrait of yeast: uncovering a phenotype for all genes

Genetics aims to understand the relation between genotype and phenotype. However, because complete deletion of most yeast genes ( approximately 80%) has no obvious phenotypic consequence in rich medium, it is difficult to study their functions. To uncover phenotypes for this nonessential fraction of the genome, we performed 1144 chemical genomic assays on the yeast whole-genome heterozygous and homozygous deletion collections and quantified the growth fitness of each deletion strain in the presence of chemical or environmental stress conditions. We found that 97% of gene deletions exhibited a measurable growth phenotype, suggesting that nearly all genes are essential for optimal growth in at least one condition.     

Multimycotoxin UPLC-MS/MS for tea, herbal infusions and the derived drinkable products

In recent years the consumption of tea and herbal infusions has increased. These hot drinks are consumed as daily drinks as well as for medicinal purposes. All tea varieties (white, yellow, green, oolong, black and puerh) originate from the leaves of the tea plant, Camellia sinensis. All extracts made of plant or herbal materials which do not contain Camellia sinensis are referred as herbal infusions or tisanes. During processing and manufacturing fungal contamination of the plant materials is possible, enabling contamination of these products with mycotoxins. In this study a multimycotoxin UPLC-MS/MS method was developed and validated for the analysis of the raw tea and herbal infusion materials as well as for their drinkable products. The samples were analyzed by ultra-high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), with a mobile phase consisting of variable mixtures of water and methanol with 0.3% formic acid. The limits of detection for the different mycotoxins varied between 2.1 μg/kg and 121 μg/kg for raw materials and between 0.4 μg/L and 46 μg/L for drinkable products. Afterward 91 different tea and herbal infusion samples were analyzed. Only in one sample, Ceylon melange, 76 μg/kg fumonisin B(1) was detected. No mycotoxins were detected in the drinkable products.     

三峡库区农村沼气综合利用途径与思考

三峡库区资源丰富,但库区农村存在资源利用不合理、能源紧缺的情况.库区的气候及资源是发展沼气的有利条件.沼气是一项投资少,见效快,一次投资长期受益的好项目;是能够解决库区农村燃料短缺,提高用能品质,促进农民增收节支的有效途径,并且是保护生态改善农村生活环境,促进库区农村生态经济可持续发展的有效举措.     

The pupal morphology of Cameraria ohridella compared with that of the genus Phyllonorycter (Lepidoptera: Gracillariidae)

The pupal morphology of the pest species Cameraria ohridella is described and compared with that of the genus Phyllonorycter. The most striking differences are the longer antennal appendages, the absence of a cremaster, the presence of strong lateral thorns on abdominal segments 1–5 and an area without small spines on the same abdominal segments in Cameraria.     

Use of geographical information systems as a tool for predicting fish yield in tropical reservoirs: case study on Sri Lankan reservoirs

Use of geographical information systems (GIS) in inland fisheries has hitherto been essentially restricted to site evaluation for aquaculture development and assessment of limnological changes in time and space in individual water bodies. The present GIS study was conducted on the land-use pattern of the catchments of nine reservoirs in Sri Lanka, for which detailed fishery data, viz. yield, fishing intensity, landing size of major constituent species, together with selected limnological data such as conductivity and chlorophyll- a , were available. Potential statistical relationships (linear, curvilinear, exponential and second-order polynomial) of fish yield ( FY , in kg ha⁻¹ yr⁻¹) to different land-use patterns, such as forest cover ( FC , in km²) and shrub-land ( SL , in km²), either singly, or in combination, and/or the ratio of each land type to reservoir area ( RA in km²) and reservoir capacity ( RC in km³), were explored. Highly significant relationships were evident between FY to the ratio of SL and/or FC + SL to RA and/or RC . Similarly, the above land-use types to RA and RC ratios were significantly related to limnological features of the reservoirs. The relationships of FY to various parameters obtained in this study were much better correlated than those relationships of FY to limnological and biological parameters used in yield prediction in tropical and temperate lacustrine waters previously.     

剡溪山水文化旅游资源开发设想

文化底蕴越是丰厚的旅游资源，开发价值就越高。正是众多文人贤士游剡访古，使浙东剡溪的历史、文化与自然山水完美地结合在一起，形成了绚丽多彩的剡溪山水文化。文化被认为是旅游业的灵魂，是一种潜在的旅游产品。要提高山水旅游产品的文化品位，必须将山水文化的潜在价值转化为旅游产品。本文对剡溪山水文化旅游资源的开发提出了以下设想：再现“唐诗之路”山水旅游美景，并着重于按唐诗及有关文献、传说等增添新景点，沿江、沿山、于水中进行山水、文化全面开发，形成立体式、全景式的剡中山水文化游道；可开发出文化生态、修学、科考、宗教、节庆等剡溪山水文化旅游产品。