Development of a rapid equine serological test (REST) by modified agar-gel immunodiffusion

A rapid equine serological test (REST) has been developed for detection of horse meat in a wide variety of raw meat products. The test is an adaptation of previously developed field screening immunodiffusion tests for beef, poultry, pork, and sheep detection. Results show that the REST test was specific, sensitive, and accurate in the analysis of 101 samples.     

Development of porcine rapid identification method (PRIME) by modified agar-gel immunodiffusion

A porcine rapid identification method (PRIME) has been developed for detection of pork in a wide variety of meat products. The test is an adaptation of previously developed field screening immunodiffusion tests for beef and poultry detection. The PRIME test was demonstrated to be specific, sensitive, and accurate in the analysis of samples in the laboratory and in a commercial meat processing establishment.     

Development of poultry rapid overnight field identification test (PROFIT)

A poultry rapid overnight field identification test (PROFIT) has been developed as a screening test which is practical, economical, and easy to perform and interpret for use in field environments to determine the presence of poultry tissue (chicken and turkey) in raw whole tissue or ground/formulated meat products. The basis of the test is an agar-gel immunodiffusion technique used with a printed template pattern and stabilized reagent paper discs. The test shows adequate sensitivity and specificity for its intended purpose. Key components are stable for at least 1 year if they are stored at refrigerator conditions. The design of the test is such that it can be made commercially available as a complete, stable, test kit suitable for use by any type of inspection program concerned with verification of poultry species in meat and/or poultry products that are subject to regulatory or quality controls.     

Detection of beef and poultry by serological field screening tests (ORBIT and PROFIT): collaborative study

Ten laboratories each analyzed 30 raw meat and raw meat product samples in a collaborative study of the ORBIT (overnight rapid bovine identification test) and PROFIT (poultry rapid overnight field identification test) serological field screening tests for the detection of beef and poultry. Versatility of the tests was shown in the analysis of whole tissue, ground, or emulsified raw meat products. Both tests were demonstrated to be reliable and were capable of detecting adulterants present at the 10% level. The method has been adopted official first action.     

同步辐射(软X射线)对水稻的细胞学效应研究

对不同剂量的同步辐射 (软X射线 )辐照水稻种子 ,研究其细胞学效应。结果表明 ,软X射线同步辐射处理后 ,在水稻根尖细胞内可诱发各类染色体结构变异。 3个品种的细胞染色体畸变率随照射剂量的增加而提高 ,有丝分裂指数明显下降。同步辐射的细胞学效应与γ射线相似。 3个品种的辐射敏感性从高至低的顺序为加育2 93 >舟 90 3 >浙 73 3     

Detection of soluble Rhizobium japonicum antigens in soil by immunodiffusion

Innovative techniques for quantifying rhizobia in soil are needed. Immunodiffusion was adapted for use in evaluating four strains of Rhizobium japonicum incubated in soil. Reproducible precipitin bands were obtained using uniform soil cores 5 mm dia × 4 mm length collected with a cork borer. A flocculent of Ca(OH)₂ and MgCO₃ added to the microcores enhanced band formation. Clear distinct bands developed from populations in soil of 1 × 10⁸ cells g^?1 or greater. The complete set of bands which characterized cells cultured on artificial media did not develop from cells inoculated into soil, but at least one detectable band was always observed. Parameters of intensity value and band positioning were related to the population in the soil. Detection by immunodiffusion of a series of rhizobial populations in soil decreased with time almost linearly as the initial population decreased. Direct diffusion of antigens from soil and the development of specific precipitin bands provides a new approach to studying soil microorganisms.     

Development of a rapid field test for soil mineral nitrogen and its application to grazed grassland

Abstract. The efficiency with which fertilizer nitrogen (N) is used in agricultural systems might be improved if the amounts applied at each top dressing were adjusted to avoid the accumulation of mineral-N in the soil profile to levels in excess of the growth requirements of the crop. Such tactical application of fertilizer would be feasible if soil mineral-N could be determined rapidly in the field with sufficient accuracy. This paper describes a rapid field test for both the ammonium and nitrate components of soil mineral-N based on reading paper test strips with a reflectometer, recalibrated for use with KC1 solution. The new test is volumetric and also accounts for the effects of fluctuations in soil water content by means of a standard dilution procedure to provide an absolute measure of soil mineral-N in about one hour. Measurements of ammonium and nitrate in a clay loam soil sampled from grazed pasture were compared with those made by conventional laboratory based methods; they generally differed by less than 5%. The proportion of mineral-N as ammonium averaged about 50% overall and typically exceeded 70% in spring. Ammonium and nitrate were not well correlated. The use of a filter-press to expel soil solution increased the sensitivity of the test five-fold to enable application in studies of soil N transformations in unfertilized and semi-natural environments.     

Toxicity of waste drilling fluids in modified allium test

The toxicity of four waste water samples from reserve pit upon the root-tip cells of Allium ascalonicum L. was researched by applying modified Allium test. The samples were a mixture of substances and their chemical composition was only partly known. The first task was to find out the optimal duration for root-tips treatment. The treatment lasting 48 h has been accepted because it enables delivery of results only four days after the sample has been received. All undiluted four waste drilling fluid samples showed cytotoxicity as well as toxicity, which was proved by cytogenetic parameters such as high inhibition of mitotic activity or low mitotic index and high percentage of chromosomal and genomic aberrations. The toxicity was significantly reduced by increasing the degree of sample dilutions. The results of this investigation demonstrated that the modified Allium test could be easily used for detection of waste drilling fluids toxicity degree.     

Sampling plan and test protocol for the semiquantitative detection of genetically modified canola (Brassica napus) seed in bulk canola seed

Using a statistical approach, sampling plans for the semiquantitative detection of genetically modified (GM) canola within a bulk seed sample can be developed and tailored to meet different GM thresholds, costs, and confidence limits. This is achieved by changing the number of subsamples analyzed, the number of seeds per subsample, and the percentage of positive results allowed. These sampling plans must be devised carefully, taking into account the detection capability of the analytical assay. This is particularly important in the case of InVigor (a registered trademark of Bayer CropScience) canola, for which expression levels of the introduced protein in seed are very low. Lateral flow assays and enzyme-linked immunosorbent assays (ELISA) were both investigated for their suitability as a qualitative assay using a subsampling approach. On the basis of an ELISA, several sampling plans have been devised and validated to provide at least 99% confidence that bulk seed samples containing at least 0.9% (w/w) InVigor canola will be detected. Although the term "seed" is used throughout this paper to refer to the canola, the term "seed" is to be taken to include both seed and the canola seed (grain) that is harvested by the farmer/grower.     

Identification of PCR-amplified genetically modified organisms (GMOs) DNA by peptide nucleic acid (PNA) probes in anion-exchange chromatographic analysis

PCR products obtained by selective amplification of transgenic DNA derived from food samples containing Roundup Ready soybean or Bt-176 maize have been analyzed by anion-exchange HPLC. Peptide nucleic acids (PNAs), oligonucleotide analogues known to bind to complementary single-stranded DNA with high affinity and specificity, have been used as specific probes in order to assess the identity of the peaks observed. Two different protocols were adopted in order to obtain single-stranded DNA: amplification with an excess of one primer or digestion of one DNA strand. The single-stranded DNA was mixed with the PNA probe, and the presence of a specific sequence was revealed through detection of the corresponding PNA:DNA peak with significantly different retention time. Advantages and limits of this approach are discussed. The method was tested with reference materials and subsequently applied to commercial samples.     

Temperature field of complex soilscapes (by the example of the Vladimir opolie region)

Problems of the assessment of soil temperature regime at the polypedon level have yet to be solved. An approach suggested by the authors consists of three stages: (1) the characterization and prediction of the soil water regime as a factor influencing the soil temperature regime, (2) the obtaining of thermophysical functions for the particular elements of complex soilscapes, and (3) the calculation and assessment of the temperature regime of complex soilscapes in the form of the functional fields of soil temperature isopleths. This approach has been applied to predict the soil temperature regime of an arable field in the Vladimir opolie region. The complex soilscape of the field consists of medium loamy agrogray soils, agrogray soils with the second humus horizon, and podzolized agrogray soils. At the beginning of the growing season, minimum temperatures are observed in the areas of agrogray soils with the second humus horizon; the difference in soil temperatures at a depth of 20 cm reaches 1°C, and the difference in the sum of active soil temperatures reaches 20°C. Then, this difference changes considerably, so that the agrogray soils with the second humus horizon become warmer than the agrogray soils. In general, the functional field of soil temperatures within the complex soilscape is highly dynamic and diverse, which is specified by the variability in the water-physical and thermophysical properties of particular soils.     

香蕉皮改性材料对废水中二价Cd离子的吸附特性与机理

为探究农业生物质制备绿色吸附材料处理含Cd~(2+)废水方法,以香蕉皮为原料,制备改性吸附材料。采用单因素试验,优化了改性工艺条件。通过静态吸附试验,结合等温模型和吸附动力学模型探讨了其对Cd~(2+)吸附过程。利用比表面及孔径分析(brunner-emmet-teller)、扫描电镜(scanning electron microscope)、能谱仪(energy disperse spectroscopy)、元素分析仪、傅里叶变换红外光谱(Fourier transform infrared spectroscopy)等手段对改性前后材料的表面形态和结构进行表征,并分析了改性和吸附过程的机理。结果表明:改性较佳工艺条件为Na OH浓度为0.25 mol/L,改性时间为30 min。在此条件下香蕉皮改性后,对水中Cd~(2+)的理论饱和吸附量由37.61 mg/g提高到87.15 mg/g,平衡时间由60 min缩短到45 min。吸附符合Langmuir等温模型(R~2=0.998)和准二级动力学模型(R2=0.999)。改性后的香蕉皮对水中Cd~(2+)的吸附以离子交换吸附为主。研究结果可为木质纤维素生物质改性制备绿色吸附材料处理含重金属废水提供理论依据。     

BS-18两性修饰膨润土对Cd（II）的吸附

为探讨两性修饰剂的结构效应,搞清不同碳链长度的两性修饰土对有机、重金属污染物的吸附特征。本文以膨润土为基质,以两性修饰剂十八烷基甜菜碱（BS-18）进行修饰,以批处理法研究BS-18两性修饰膨润土对Cd（II）的平衡吸附特征和机理。结果表明, BS-18修饰膨润土在修饰比例小于100?C时,其对Cd2 的平衡吸附量随修饰比例的增加而减小,超出100%修饰比例后对Cd2 吸附能力则增强且高于未修饰膨润土。不同碳链长度两性修饰剂修饰膨润土吸附性能上的差异主要体现在超出100%修饰比例上。BS-18修饰膨润土样对Cd2 吸附呈现“感温钝化”现象。苯酚的共存对低修饰比例土样吸附Cd2 具有抑制作用,而对高修饰比例土样吸附Cd2 具有促进作用。pH升高和离子强度的降低均可促进Cd2 吸附。机理讨论认为,以电性引力形式修饰在的膨润土表面上的BS-18不利于Cd2 吸附作用,而以疏水键形式吸附膨润土表面上的BS-18却促进了Cd2 吸附,与BS-12修饰膨润土吸附效应的比较证实了这一机制。     

同步辐射(软X、紫外)辐照麦类作物种子的诱变效应

同步辐射（软Ｘ,超软Ｘ射线）辐照麦类作物种子的生物学效应显。Ｍ１代出现条状叶绿素缺失,其出现率高达４０％－１００％〈其中大麦的缺失有４种类型,这在γ辐照中没有出现。Ｍ２工出现了宽的突变谱,最高达９种类型的突变,其最高总突变率为γ射线的２．７倍,有益突变率为γ射线的５．７倍。     

A simple field test for predicting ease of cultivation

A simple field test is postulated for assessing ease of cultivation. In the proposed test, representative clods are sampled from the field, and place in portable apparatus where they are split between a cone and a ball. The force and movement to split the clod are recorded; average peak force is then plotted against clod deformation at peak force. Some preliminary data have been accumulated and plotted over a range of soil conditions. With sufficient data, areas on the graph can be identified, indicating that the soil is in a suitable or unsuitable condition for cultivation by a given implement.     

Absorption and accumulation of cadmium by ramie (Boehmeria nivea) cultivars: A field study

Abstract

Ramie is a fibre crop originating from China that has great ability to tolerate and accumulate heavy metals. This study has analysed the capacity of ramie cultivars to absorb and accumulate cadmium (Cd) through two years of micro-regional field study and shown that stress under high concentration of Cd significantly affects the biomass of ramie; 25 mg kg^?1 Cd treatment promotes the growth and development of ramie cultivars B. nivea 1 and 9. The Cd contents retained in different parts of ramie are ranked as the following: bast > stems > leaves. Cd concentrations in shoot systems among different ramie cultivars are significantly different and increase dramatically in association with the increasing Cd concentration in the soil. Ramie has the ability to accumulate large amounts of Cd; under the treatment with 25 and 100 mg kg^?1 of Cd, three times of ramie harvest annually remove 0.76 and 0.97 kg hm^?2 a^?1 of Cd respectively. The results from this study demonstrate the feasibility of phytoremediation of Cd-contaminated farmland by ramie cultivars that have obtained Cd accumulating capacity through screening and training.     

The snowfall chemistry collector intercomparison test (SCCIT)

The Snowfall Chemistry Collector Intercomparison Test (SCCIT) took place as part of a field experiment of the PRocessing of Emissions by Clouds and Precipitation (PRECP) program during January and February 1986 in western New York. SCCIT compared the chemical composition and equivalent water depth of snow collected with a large, bag-lined can (used by the PRECP community for a concurrent surface snowfall network); the most widely used automatic wet/dry collector; an aerodynamically designed, heated, funnel and bottle system; and a large plastic sheet. The aerodynamically designed system had significantly higher concentrations of analytes than the other systems, particularly H⁺ and SO₄ ^2?, apparently because of evaporative losses. Samples from the bag-lined can were more acidic than those from the automatic wet/dry collector. The aerodynamically designed system and the bag-lined can indicated greater snow amounts than the other methods.