MODELING CLIMATE CHANGE AND THE EFFECT ON THE NORWEGIAN SALMON FARMING INDUSTRY

Abstract Global warming is expected to affect the ecosystem in the Northeast Atlantic, and substantial changes will also affect the aquaculture industry. Farming of salmon and trout is the biggest aquaculture industry in Norway, with an export value of about 3 billion US dollars in 2007. The objective of the paper is to analyze the potential economic effect a general increase in sea temperature can have on the Norwegian salmon aquaculture industry. The assessment of the economic impact of global warming is made possible by estimating a growth function, which explicitly includes sea water temperature. The analysis compares the economic effect of a climate change on fish farming plants in the south and the north of Norway. The scenarios are based on a model with monthly seasonal variation in temperature.     

Manipulation of the Phytochemical Profile of Tenderstem® Broccoli Florets by Short Duration,Pre-Harvest LED Lighting

Light quality has been reported to influence the phytochemical profile of broccoli sprouts/microgreens; however, few studies have researched the influence on mature broccoli. This is the first study to investigate how exposing a mature glasshouse grown vegetable brassica, Tenderstem^® broccoli, to different light wavelengths before harvest influences the phytochemical content. Sixty broccoli plants were grown in a controlled environment glasshouse under ambient light until axial meristems reached >1 cm diameter, whereupon a third were placed under either green/red/far-red LED, blue LED, or remained in the original compartment. Primary and secondary spears were harvested after one and three weeks, respectively. Plant morphology, glucosinolate, carotenoid, tocopherol, and total polyphenol content were determined for each sample. Exposure to green/red/far-red light increased the total polyphenol content by up to 13% and maintained a comparable total glucosinolate content to the control. Blue light increased three of the four indole glucosinolates studied. The effect of light treatments on carotenoid and tocopherol content was inconclusive due to inconsistencies between trials, indicating that they are more sensitive to other environmental factors. These results have shown that by carefully selecting the wavelength, the nutritional content of mature broccoli prior to harvest could be manipulated according to demand.     

火焰原子吸收光谱法测定羊血中铁、铜和锌3种微量元素

建立了湿法消解-火焰原子吸收光谱法对羊血中Fe、Cu和Zn 3种微量元素测定的方法.方法的校准曲线线性关系良好（r=0.9965-0.9999）,方法加标回收率（n=5）在96.2％-98.5％之间,RSD值（n=5）在1.3％-4.9％之间.为了解动物微量元素含量提供参考,也为进一步研究畜禽疾病与微量元素的相关性提供基础资料.     

期权合约在订单农业中的应用

订单农业作为一种基于远期合约的农产品销售模式,被认为是解决农产品流通困难问题并实现农业产业化经营的重要出路,但订单农业的价值由于其普遍存在的违约现象而大打折扣。本文在合约不完全性的前提下,用一个简单的单期保护价模型说明了生产条件和市场条件的不可预知性是订单农业违约的根本原因,并证明此时一定存在农产品专用性投资不足的问题。而低水平的专用性投资既降低了履约的概率,又降低了订单交易所能产生的附加值。在此基础上,本文给出了一种具有期权性质的农产品合约,并证明经过相应的再谈判程序,期权合约既可以像传统订单合约一样帮助农户规避市场风险,又可以解决传统订单下无效率的单方面毁约问题。最后,本文证明了在期权合约下,农户和农产品收购商都将作出最优水平的专用性投资,低水平专用性投资带来的低附加值问题由此得到解决。     

Analysis of nucleotide variation within the triose‐phosphate isomerase gene of Giardia duodenalis from sheep and its zoonotic implications

This study explored the genetic composition of Giardia in fecal samples from 284 individual lambs on pasture‐based sheep farms in three regions of Victoria, Australia. An approach, combining targeted sequencing, phylogenetic analysis and PCR‐coupled restriction endonuclease fingerprinting, was used to identify and genetically categorize Giardia present in 43 (15.1%) of the 284 samples and to infer their zoonotic potential. The specific identity and genetic classification were based on the phylogenetic analysis of sequence data for a portion of the triose‐phosphate isomerase gene. Fourteen different sequence variants (including seven sequences that contained between one and five polymorphic sites) representing two distinct assemblages of Giardia (recognized in the current literature) were defined, of which 13 were new records. One dominant sequence type (with accession no. GQ444447, representing a genotype within assemblage A) has been detected previously in humans and is thus considered to be of zoonotic potential. (Nucleotide sequences reported in this article are available in the GenBank database under accession nos. GQ444447–GQ444451 and GQ444454–GQ444462).     

Preparation of the Mn-Fe-Ce/γ-Al2O3 ternary catalyst and its catalytic performance in ozone treatment of dairy farming wastewater

The quality of dairy farming wastewater in different regions is particular and different. In Southern China, the Chemical Oxygen Demand (COD_Cr) and colourity of effluent from conventional dairy farming wastewater treatment processes are similar. Catalytic ozonation is a very promising technical method. In this paper, the Mn-Fe-Ce/γ-Al₂O₃ catalyst was prepared via the optimized preparation method of impregnation roasting using γ-Al₂O₃ as the carrier, and this catalyst was used in the ozonation of actual dairy farming wastewater from treatment facilities. The performance of the Mn-Fe-Ce/γ-Al₂O₃ catalyst on dairy farming wastewater was investigated using a simulated dynamic test. The effects of the reaction time, pH and catalyst dosage on COD_Cr and the colourity removal ratio were investigated. The results show that the optimum treatment conditions were a reaction time of 20 min, pH 9, and catalyst dosage of 15 g/L. The COD_Cr removal ratio reached 48.9% and the colourity was 95% under the optimum conditions. BOD₅/COD_Cr increased from 0.21 to 0.54 after catalytic ozonation, indicating that the biodegradability of wastewater was significantly improved. This research provides a new method and theoretical guidance for dairy farming wastewater treatment.     

Development of a group selective molecularly imprinted polymers based solid phase extraction of malachite green from fish water and fish feed samples

A group selective molecularly imprinted solid phase extraction (MISPE) for malachite green (MG) from fish water and fish feed samples was developed. Using MG as template molecule, methacrylic acid as functional monomer, ethylene glycoldimethacrylate as linking agent and bulk polymerization as synthetic method, the molecularly imprinted polymers (MIPs) were synthesized and characterized with rebinding experiment. The Scatchard polt's analysis revealed that the template-polymer system showed the two-site binding behavior with dissociation constants of 0.3194 μmol L⁻¹ and 15.70 μmol L⁻¹, respectively. MG and two structurally related compounds, leucomalachite green (LMG) and crystal violet (CV) were employed for selectivity test. The MIPs exhibited the highest selective rebinding to MG, but also displayed 83.0% and 87.5% of cross-reactivity with LMG and CV, demonstrating that MIPs could be used as group recognition sorbents in solid phase extraction. The extraction conditions of MISPE column for MG were optimized. Tap water samples spiked with MG at concentration of 0.5-10 ng mL⁻¹ were extracted by MISPE column and analyzed by high performance liquid chromatography. The recoveries of MISPE column for MG extraction were found to be 76.8-93.7% with the relative standard deviations of 2.12-10.09%, indicating the feasibility of the prepared MIPs for MG extraction. No detectable MG was observed in one fish farming water sample and two fish feed samples; while the MG concentrations in two pet fishpond water samples were found at 1.50 ng mL⁻¹ and 0.67 ng mL⁻¹, respectively.     

Measurement of the electrophoretic mobility of sheep erythrocytes using microcapillary chips

Cell electrophoretic mobility (EPM) can be used to characterize individual cells. The purpose of this study is to establish reproducible and reliable cell EPM values obtained using microcapillary electrophoresis (microCE) chips. We studied cell electrophoresis on microCE chips through the comprehensive measurement of EPM and zeta potential. The inner wall of microchannels in microCE chips was coated with three kinds of reagents, namely bovine serum albumin (BSA), gelatin, and 2-methacryloyloxyethylphosphorylcholine (MPC) polymer to prevent nonspecific adhesion and interaction between cells and the inner wall. Electrophoresis was conducted in phosphate-buffered saline (pH 4-9) using erythrocytes extracted from sheep whole blood. Electroosmotic flow (EOF) mobility was measured using noncharged particles, and then the true EPM was calculated by subtracting the EOF mobility from the electromigration. MPC polymer coatings in microCE chips reduced the zeta potential of the inner wall and fully prevented nonspecific adhesion. EPM data obtained using microCE chips were almost the same and reproducible over a wide range of pH irrespective of the coating reagent used. In conclusion, reliability in the measurement of cell EPM using microCE chips was realized.     

A BIOECONOMIC SHEEP–VEGETATION TRADE‐OFF MODEL: AN ANALYSIS OF THE NORDIC SHEEP FARMING SYSTEM

Abstract. The paper studies the economy and ecology of sheep farming at the farm level and includes 2 different categories of the animals, ewes (adult females) and lambs. The model is analyzed in a Nordic economic and biological setting. During the outdoor grazing season, animals face limited grazing resources so that the weight gain of lambs is determined by the per‐animal vegetation consumption. On the other hand, the number of grazing animals, lambs as well as ewes, determines the grazing pressure. This problem is studied under the assumption of a rational and well‐informed farmer who aims to maximize profit in ecological equilibrium with zero animal and vegetation growth. We find that lamb‐only slaughtering is optimal and that it is never beneficial for the farmer to keep livestock that overgraze pasture. It is also shown that higher meat prices and more profitable slaughtering make it economically rewarding for the farmer to keep more animals. A numerical illustration indicates that the optimal sheep farming decision may be more sensitive to changes in pasture quality and productivity than changes in economic conditions.     

X射线能谱研究鞣性金属在绵羊皮革中的分布

以绵羊皮革为研究对象,利用X射线能谱仪(EDXA)分析了鞣性金属锆铬在绵羊皮革中的分布,结果表明:鞣性金属元素锆、铬在绵羊皮革中的分布整体上比较均匀,但局部存在不均匀现象,鞣性金属组分主要分布于纤维束边缘,纤维束的空隙和内部含量均较低.