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991.
Animal welfare in cross-ventilated, compost-bedded pack, and naturally ventilated dairy barns in the upper Midwest 总被引:2,自引:0,他引:2
The objective of this cohort study was to investigate animal welfare in 2 newer dairy housing options in the upper Midwest, cross-ventilated freestall barns (CV) and compost-bedded-pack barns (CB), compared with conventional, naturally ventilated freestall barns (NV). The study was conducted on 18 commercial dairy farms, 6 of each housing type, in Minnesota and eastern South Dakota. The primary breed in all farms was Holstein; 1 CV and 1 NV herd had approximately 30% Jersey-Holstein crossbreds. All freestall herds used sand for bedding. Farms were visited 4 times (once in each season) between January and November 2008, and approximately 93% of all animals in each pen were visually scored on each visit. Outcome-based measurements of welfare (locomotion, hock lesions, body condition score, hygiene, respiration rates, mortality, and mastitis prevalence) were collected on each farm. Lameness prevalence (proportion of cows with locomotion score ≥3 on a 1 to 5 scale, where 1 = normal and 5 = severely lame) in CB barns (4.4%) was lower than that in NV (15.9%) and CV (13.1%) barns. Lameness prevalence was similar between CV and NV barns. Hock lesion prevalence (proportion of cows with a lesion score ≥2 on a 1 to 3 scale, where 1 = normal, 2 = hair loss, and 3 = swelling) was lower in CB barns (3.8%) than in CV (31.2%) and NV barns (23.9%). Hygiene scores (1 to 5 scale, where 1 = clean and 5 = very dirty) were higher for CB (3.18) than CV (2.83) and NV (2.77) barns, with no differences between CV and NV barns. Body condition scores, respiration rates, mastitis prevalence, culling, and mortality rates did not differ among housing systems. The CV and NV barns were evaluated using the cow comfort index (proportion of cows lying down in a stall divided by all animals touching a stall) and the stall usage index (proportion of cows lying divided by all animals in the pen not eating). The CV barns tended to have greater cow comfort index (85.9%) than the NV barns (81.4%) and had greater stall usage index (76.8% and 71.5%, respectively). Dairy cattle housed in CB barns had reduced lameness and hock lesions compared with those housed in freestall barns and had no adverse associations with body condition, respiration rates, mastitis prevalence, culling, or mortality. When comparing the 2 freestall housing options, CV barns had improved cow comfort indices compared with NV barns. Although cows in CB barns had better feet and leg health, as indicated by the reduced lameness and hock lesion prevalence, acquiring bedding and managing the bedded pack could limit their use. 相似文献
992.
Hoerger CC Wettstein FE Bachmann HJ Hungerbühler K Bucheli TD 《Environmental science & technology》2011,45(16):6752-6760
Isoflavones and coumestrol (COU) are estrogenic compounds that are naturally produced by plants (e.g., red clover, soybeans). Although these compounds have been extensively studied in food and feed, only little is known about their environmental fate. Therefore, we investigated the occurrence of isoflavones (formononetin, daidzein, equol, biochanin A, and genistein) and COU over 3.5 years in red clover, manure, and soil of a grassland field with and without manure application, as well as their emission via drainage water. Isoflavones were regularly quantified in plant (≤ 15 × 10(6) ng/g(dry weight (dw))), manure (≤ 230 × 10(3) ng/g(dw)), soil (≤ 3.4 × 10(3) ng/g(dw)), and drainage water samples (≤ 3.6 × 10(3) ng/L). In contrast, COU was observed only in manure and soil. Cumulative isoflavone loads emitted via drainage water were around 0.2 × 10(-3) kg/ha/y, which is very little compared to the amounts present in red clover (105-220 kg/ha/y), manure (0.5-1.0 kg/ha/y), and soil (0.1-5.1 kg/ha/y). Under good agricultural practice, no additional emission of isoflavones into drainage water was observed after manure application. With calculated 17β-estradiol equivalents up to 0.46 ng/L in drainage water, isoflavones can constitute a dominant and ecotoxicological relevant portion of the total estrogenicity in small rural river catchments. 相似文献
993.
V. Golyk S. HuberM.G. Farghaly G. PrölssE. Endres T. NeesseM.A. Hararah 《Minerals Engineering》2011,24(2):98-101
In kaolin classification, the final product is isolated from the overflow of a 50 mm hydrocyclone with an underflow containing fine sand and residual kaolin. For a higher kaolin recovery, the underflow is usually further treated using a washing cyclone. This paper presents a new development in fine sand washing using water injection in the conical section of the classifying cyclone. This washing results in a 45-50% reduction of the kaolin fraction (<10 μm) in the underflow. Thus, water injection into the classifying cyclone leads to a separation comparable to downstream washing. 相似文献
994.
Moran CL Le VH Chimalakonda KC Smedley AL Lackey FD Owen SN Kennedy PD Endres GW Ciske FL Kramer JB Kornilov AM Bratton LD Dobrowolski PJ Wessinger WD Fantegrossi WE Prather PL James LP Radominska-Pandya A Moran JH 《Analytical chemistry》2011,83(11):4228-4236
"K2/SPICE" products are commonly laced with aminoalkylindole synthetic cannabinoids (i.e., JWH-018 and JWH-073) and are touted as "legal" marijuana substitutes. Here we validate a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for measuring urinary concentrations of JWH-018, JWH-073, and several potential metabolites of each. The analytical procedure has high capacity for sample throughput and does not require solid phase or liquid extraction. Evaluation of human urine specimens collected after the subjects reportedly administered JWH-018 or a mixture of JWH-018 and JWH-073 provides preliminary evidence of clinical utility. Two subjects that consumed JWH-018 primarily excreted glucuronidated conjugates of 5-(3-(1-naphthoyl)-1H-indol-1-yl)-pentanoic acid (>30 ng/mL) and (1-(5-hydroxypentyl)-1H-indol-3-yl)(naphthalene-1-yl)-methanone (>50 ng/mL). Interestingly, oxidized metabolites of both JWH-018 and JWH-073 were detected in these specimens, suggesting either metabolic demethylation of JWH-018 to JWH-073 or a nonreported, previous JWH-073 exposure. Metabolic profiles generated from a subject who consumed a mixture of JWH-018 and JWH-073 were similar to profiles generated from subjects who presumably consumed JWH-018 exclusively. Oxidized metabolites of JWH-018 and JWH-073 were of the same pattern, but JWH-018 metabolites were excreted at lower concentrations. These results begin clinically validating the LC-MS/MS assay for detecting and quantifying aminoalkylindole metabolites. Full validation awaits further testing. 相似文献
995.
Thomas M. Amrein Luca Andres Barbara Schönbächler Béatrice Conde-Petit Felix Escher Renato Amadò 《European Food Research and Technology》2005,221(1-2):14-18
Acrylamide was determined in 86 different almond products, such as roasted almonds, almond-containing bakery products, raw almonds, and marzipan. The highest acrylamide concentrations were found in dark roasted almonds, while only moderate acrylamide contents were determined in bakery products. Roasting experiments under different process conditions showed that acrylamide increases with time and that temperature has a much stronger effect on acrylamide formation than time. During roasting reducing sugars are consumed faster and to a larger extent than free asparagine, suggesting that the content of reducing sugars may be a critical factor for acrylamide formation in roasted almonds. Acrylamide was found to decrease in roasted almonds during storage at room temperature. 相似文献
996.
Enobong Felix Daniel Junhua Dong Xiaofang Li Ini-Ibehe Nabuk Etim Inime Ime Udoh Rongyao Ma Lei Chen Changgang Wang 《金属学报(英文版)》2022,35(4):563
An experimental model for simulating the corrosion of carbon steel fasteners (bolt and nut) composed of a contact carbon steel electrode (CCSE) and an exposed bare carbon steel plate electrode (BCSE) was designed. The effect of coupling on the corrosion process of the galvanically coupled carbon steel electrode was evaluated and compared with the self-corrosion process observed independently at the exposed and contact regions. Results obtained indicated that at an equal area ratio and uncoupled conditions, the corrosion rate is accelerated in the surface directly exposed to bulk solution compared to the bolt surface in contact with the nut. A coupling current was recorded when the exposed surface (BCSE) was electrically connected with the contact surface (CCSE); with the CCSE acting as the anode thereby suppressing the corrosion process in the exposed surface. By implication, the galvanic coupling between CCSE and BCSE increased the corrosion rate of CCSE. The difference in oxygen supply was responsible for the coupling effect observed in the system as there was no decrease in the solution pH. Moreover, varying the cathode-to-anode area (Sc/Sa) ratio significantly influenced the corrosion current density as increased Sc/Sa ratio resulted in an accelerated galvanic corrosion process. The corroded surfaces and interfaces were analysed using stereomicroscopy and scanning electron microscopy. X-ray diffractometry was adopted for corrosion product characterization. The results obtained showed supportive evidence of the corrosion behaviour in carbon steel fasteners. 相似文献
997.
Minor components are the non‐triacylglycerol constituents of oil and constitute up to 5% of the total lipid composition. Though minor in composition, they can exert major influence on the performance of oil during frying. The effect of the minor components on frying performance depends on their chemical nature, composition and amount in the oil. Among these minor components tocopherols, phytosterols, phospholipids, γ‐oryzanol, lignans, phenolics, and carotenoids are the most important. Here, their effect on the frying performance of edible oils is discussed. 相似文献
998.
Formic acid, containing 4.4 wt% of hydrogen, is a non-toxic liquid at ambient temperature and therefore an ideal candidate as potential hydrogen storage material. Formic acid can be generated via catalytic hydrogenation of CO2 or bicarbonate in the presence of an amine with suitable ruthenium catalysts. In addition selective dehydrogenation of formic acid amine adducts can be carried out at ambient temperatures with either ruthenium phosphine catalyst systems as well as iron-based catalysts. In detail we obtained with the [RuCl2(benzene)]2/dppe catalyst system a remarkable TON of 260,000 at room temperature. Moreover applying Fe3(CO)12 together with tribenzylphosphine and 2,2':6',2"-terpyridine under visible light irradiation a TON of 1266 was obtained, which is the highest activity known to date for selective dehydrogenation of formic acid applying non-precious metal catalysts. 相似文献
999.
Tymofiyeva O Schmid F von Kienlin M Breuer FA Rottner K Boldt J Richter EJ Jakob PM 《Magma (New York, N.Y.)》2011,24(1):19-28
Object
The purpose of this study was to investigate the achievable precision of localization of boundaries between extended uniform objects in MRI and to study the effect of zero-filling on reaching it. 相似文献1000.
Jeffrey J. Richards Andrew H. Rice Rainie D. Nelson Felix S. Kim Samson A. Jenekhe Christine K. Luscombe Danilo C. Pozzo 《Advanced functional materials》2013,23(4):514-522
The morphological effects of the incorporation of C60 into blended thin‐films of poly(3‐hexylthiophene) and [6,6]‐phenyl C61 butyric acid methyl ester (PCBM) are investigated. The results show that addition of C60 readily alters the growth‐rate and morphology of PCBM crystallites under different environmental conditions. The effect of C60 on the growth of large PCBM crystallites is thoroughly characterized using optical microscopy, electron microscopy and UV‐visible absorption spectroscopy. Results show that C60 incorporation modifies fullerene aggregation and crystallization and greatly reduces the average crystallite size at C60 loadings of ≈50 wt% in the fullerene phase. Organic field‐effect transistors (OFETs) are prepared to evaluate the electron mobility of PCBM/C60 films and organic solar cells (OSCs) are fabricated from mixed‐fullerene active layers to evaluate their performance. It is demonstrated that the use of fullerene mixtures in organic electronic applications is a viable approach to produce more stable devices and to control the growth of micrometer‐sized fullerene crystals. 相似文献