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141.
The objective of this study was to identify the major electricity and water-consuming components of a pasture-based automatic milking (AM) system and to establish the daily and seasonal consumption trends. Electricity and water meters were installed on 7 seasonal calving pasture-based AM farms across Ireland. Electricity-consuming processes and equipment that were metered for consumption included milk cooling components, air compressors, AM unit(s), auxiliary water heaters, water pumps, lights, sockets, automatic manure scrapers, and so on. On-farm direct water-consuming processes and equipment were metered and included AM unit(s), auxiliary water heaters, tubular coolers, wash-down water pumps, livestock drinking water supply, and miscellaneous water taps. Data were collected and analyzed for the 12-mo period of 2015. The average AM farm examined had 114 cows, milking with 1.85 robots, performing a total of 105 milkings/AM unit per day. Total electricity consumption and costs were 62.6 Wh/L of milk produced and 0.91 cents/L, respectively. Milking (vacuum and milk pumping, within-AM unit water heating) had the largest electrical consumption at 33%, followed by air compressing (26%), milk cooling (18%), auxiliary water heating (8%), water pumping (4%), and other electricity-consuming processes (11%). Electricity costs followed a similar trend to that of consumption, with the milking process and water pumping accounting for the highest and lowest cost, respectively. The pattern of daily electricity consumption was similar across the lactation periods, with peak consumption occurring at 0100, 0800, and between 1300 and 1600 h. The trends in seasonal electricity consumption followed the seasonal milk production curve. Total water consumption was 3.7 L of water/L of milk produced. Water consumption associated with the dairy herd at the milking shed represented 42% of total water consumed on the farm. Daily water consumption trends indicated consumption to be lowest in the early morning period (0300–0600 h), followed by spikes in consumption between 1100 and 1400 h. Seasonal water trends followed the seasonal milk production curve, except for the month of May, when water consumption was reduced due to above-average rainfall. This study provides a useful insight into the consumption of electricity and water on a pasture-based AM farms, while also facilitating the development of future strategies and technologies likely to increase the sustainability of AM systems.  相似文献   
142.
Doxorubicin (DOX), a powerful anthracycline antibiotic commonly used to treat a wide variety of cancers, is associated with the production of reactive oxygen species that cause oxidative damage, resulting in cardiac dysfunction. Components of dairy may have protective effects against DOX-induced cardiac damage. Kefir is a naturally fermented milk product containing antioxidants, probiotic bacteria, and yeast in addition to the protective components of dairy. We explored the effects of dietary milk and kefir on DOX-induced cardiotoxicity in rats. We used singly housed, 10-wk-old male Sprague Dawley rats assigned to 1 of 3 isocaloric diets, control (CON n = 24), milk (MLK, n = 24), or kefir (KEF, n = 24), with equivalent macronutrient profiles. After a 9-wk dietary intervention, all animals were given either a bolus injection (15 mg/kg) of DOX (CON-DOX n = 12; MLK-DOX n = 12, KEF-DOX n = 12) or saline (CON-SAL n = 12; MLK-SAL n = 12; KEF-SAL n = 12). Body weight, grip strength, echocardiographic evaluation of cardiac geometry, and cardiac function were evaluated using echocardiography at 5 d postinjection and data were analyzed using ANOVA. Survival at d 5 post-DOX injection was 92 and 100% in KEF-DOX and MLK-DOX, respectively, and 75% in CON-DOX. By the last week of the dietary intervention, and just before injection with saline or DOX, CON weighed significantly (14%) more than the MLK and KEF. The DOX treatment resulted in significant reductions in body weight; however, we found no diet × drug interactions. The DOX treatment reduced peak grip strength compared with SAL; when compared with pre-injection measures, MLK-DOX rats did not experience a significant reduction in peak grip strength compared with CON-DOX and SAL-DOX rats. Heart mass in MLK and KEF was significantly higher when compared with CON. In summary, 9 wk of milk or kefir ingestion resulted in lower body size and higher heart mass after DOX treatment. Additionally, MLK preserved peak grip strength after DOX treatment, whereas KEF or CON did not. We observed no consistent protective effects with respect to heart dimensions and function. These findings suggest that long-term milk or kefir ingestion may be helpful in optimizing health before and during doxorubicin treatment.  相似文献   
143.
The purpose of this study was to model the effect of 3 divergent strains of Holstein-Friesian cows in 3 pasture-based feed systems on greenhouse gas (GHG) emissions. The 3 strains of Holstein-Friesian compared were high-production North American (HP), high-durability North American (HD), and New Zealand (NZ). The 3 feed systems were a high grass allowance system (MP, control); high stocking rate system (HS); and high concentrate supplementation system (HC). The MP system had an overall stocking rate of 2.47 cows/ha and received 325 kg of dry matter concentrate per cow in early lactation. The HS system had a similar concentrate input to the MP system, but had an overall stocking rate of 2.74 cows/ha. The HC system had a similar overall stocking rate to the MP system, but 1,445 kg of dry matter concentrate was offered per cow. A newly developed integrated economic-GHG farm model was used to evaluate the 9 milk production systems. The GHG model estimates on-farm (emissions arising within the farm's physical boundaries) and production system (incorporating all emissions associated with the production system up to the point milk leaves the farm gate) GHG emissions. Production system GHG emissions were always greater than on-farm emissions, and the ranking of the 9 systems was usually consistent under both methods. The exception was the NZ strain that achieved their lowest GHG emission per unit of product in the HC system when indirect emissions were excluded, but their lowest emission was in the HS system when indirect emissions were included. Generally, the results showed that as cow strain changed from lower (HD and NZ) to higher genetic potential (HP) for milk production, the GHG emission per kilogram of milk solids increased. This was because of a decline in cow fertility in the HP strain that resulted in a higher number of nonproductive animals, leading to a lower total farm milk solids production and an increase in emissions from nonproductive animals. The GHG emission per hectare increased for all strains moving from MP to HS to HC feed systems and this was associated with increases in herd total feed intake. The most profitable combination was the NZ strain in the HS system and this combination resulted in a 12% reduction in production system GHG emission per hectare compared with the NZ strain in the HC system, which produced the highest emissions. This demonstrates that grass-based systems can achieve high profitability and decreased GHG emissions simultaneously.  相似文献   
144.
The aim of this study was to measure the effect of type of diet and level of energy intake on the performance of cows undergoing extended lactations. Ninety-six Holstein-Friesian cows that calved in July and August 2004 were assigned randomly to 1 of 8 groups each of 12 cows (including 4 primiparous cows). Two of the 8 groups were assigned to each of 4 treatments that varied in lactation length (300 or 670 d) and diet (3 diets: control, high, or full total mixed ration (TMR). The 4 treatments were 1) control 300: cows were managed for a 300-d lactation and grazed pasture supplemented with grain and forage to provide a minimum daily dietary intake of 160 MJ of ME/cow; 2) control 670: as for control 300 except that cows were managed for a 670-d lactation; 3) high 670: cows were managed for a 670-d lactation and pasture was supplemented with grain and forage to provide a minimum daily dietary intake of 180 MJ of ME/cow; 4) full TMR 670: cows were managed for a TMR system that included a high body condition score at calving with cows offered a TMR during a 670-d lactation. The TMR was initially offered ad libitum indoors until about 440 DIM when the amount of TMR offered was reduced by about 2 kg of DM/d to prevent excessive weight gain. The proportions of cows still milking at the end of a 670-d lactation were similar for the control and high dietary groups. The full TMR group had fewer cows milking at 600 DIM: 17 cows milking compared with 24 cows in the control 670 group and 22 cows in the high 670 group. For the period 1 to 670 DIM, increasing the energy level in the diet (control 670 vs. high 670) resulted in a similar yield of milk and a similar fat concentration in the milk, but greater yields of milk fat and protein and greater milk protein percentage of the milk. The full TMR 670 group produced greater yields of milk and milk components (fat, protein, and lactose) and also protein percentage in the milk than the other groups. The milk solids (fat + protein) ratio for the 3 extended-lactation groups, defined as production achieved during the 24-mo calving interval divided by 2 yr (annualized production) expressed as a ratio of that produced in the normal 12-mo calving interval, was not affected by increasing the level of grain in the pasture-based diets (0.93 vs. 0.90 for control and high diets, respectively), but decreased with the TMR diet (0.79). The control 670 group produced 7.1% less milk, but only 2.4% less milk solids than the control 300 group over the 2-yr period of the study. Combining our data with that from 2 earlier studies of extended lactation demonstrated that Holstein cows with a high proportion of Northern Hemisphere genes offered pasture-based diets could achieve a high milk solids ratio, a greater proportion of cows milking at drying-off, and lower body weight gain over the lactation.  相似文献   
145.
An alternative method for detection of Salmonella spp. in animal feed, based on the use of loop-mediated amplification (LAMP) in conjunction with a standard culturing procedure, was compared with the standard ISO 6579 as reference method, using soya meal as the test matrix. In the method comparison study, the sensitivities for both the alternative and reference methods were 100 %. The relative level of detection was 1.000. Tested against 100 Salmonella and 30 non-Salmonella strains, the LAMP-based method was 99 % inclusive and 100 % exclusive. The interlaboratory trial involved ten laboratories from eight European countries, testing eight samples at three contamination levels: 0 cfu/100 g, 1–5 cfu/100 g and 14–68 cfu/100 g. The trial specificity, or percentage correct identification of uncontaminated samples, was 96.3 % for both the reference methods and the LAMP/ISO 6579 alternative method, thus demonstrating its suitability for adoption as a procedure for rapid identification of Salmonella uncontaminated soya meal.  相似文献   
146.
Synchrotron-based X-ray techniques, such as Diffraction and Absorption Spectroscopy (XAS), can be readily employed to study catalysts in action, thereby offering great potential for revealing the mechanism and behaviour of catalytic solids both during preparation and reaction. The continued advancement of X-ray generation and collection mean that it is now possible to obtain high quality data from catalysts under reaction conditions with second/sub-second time resolution. In this paper, we describe in detail a specific setup which can be used to obtain transmission in situ data. It is able to mimic industrial preparation/reaction environments and has been developed to such an extent that such measurements are now routine. To illustrate its applicability, we present time-resolved diffraction data obtained from an iron molybdate-based catalyst under pseudo industrial operating conditions revealing its bulk solid-state chemistry and stability, and further show how the catalyst behaviour changes as a function of the Fe/Mo ratio. We also illustrate the versatility of this setup in obtaining data using simultaneous multiple techniques (including non-X-ray-based methods, e.g. UV–vis) from an iron molybdate catalyst under methanol/air-flow. We conclude with a brief outlook towards the future, in which we identify new possibilities for studying catalysts in action which could yield insight into their preparation and behaviour.  相似文献   
147.
New data are presented describing the retention time and longitudinal dispersion of a solute tracer across circular surcharged manhole structures of different diameters. The variations with both discharge and surcharge level are described and the relationships quantified. The variation of the longitudinal dispersion coefficient exhibits poorly defined trends, however using an aggregated dead zone technique both the reach time delay and travel time show clear variations. A surcharge threshold level for these parameters is evident at the larger manhole diameters and this is explained in relation to jet theory. The variation of the surcharge mean time delay and postthreshold mean travel time are quantified, while the prethreshold travel times are shown to be dependent on both discharge and surcharge. The relationships allow for inclusion in sewer water quality modeling and provide a method for improving predictive techniques.  相似文献   
148.
Metallurgical and Materials Transactions B - The distributions of Ga, In, Sn, and Te between copper-iron mattes and silica-saturated iron silicate slags over a wide range of matte grades 55 to 75...  相似文献   
149.
150.
A new technique for the observation and interpretation of concentration profiles in diffusion layers at membrane-solution interfaces was developed. The concentration profiles in dilute (0·01N) KCl solutions near an ion-exchange membrane were observed in a modified O'Brien-type wedge laser interferometer while electric current (1·15 and 2·3 mA cm?2) passed through the solution (25°C). After current reversal, following prepolarization periods of 5–60 s, a concentration minimum develops. The image of this minimum in relation to the membrane surface is not subject to optical deflection and can therefore be accurately determined. From its trajectory, the salt concentration at the membrane surface at the time of current reversal was determined. It was found that as this concentration dropped to the order of 10?3–10?4M (“critical concentration”) significant deviations occurred between observed trajectories and those computed from a theory based on the Nernst-Planck equations. These deviations are believed to be caused by substantial migration of H+ and OH?. While these measurements indicate the order of magnitude of the critical concentration, additional measurements are necessary for quantitative determination of this concentration under different physicochemical and hydrodynamic conditions.  相似文献   
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