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61.
A review of past literature revealed inconsistencies in recommended feed particle size for optimal growth and productive performance of rabbits. Changing diet formulation and subsequent processing conditions may improve pellet texture and potentially affect rabbit performance. In the current study, two isoenergetic and isonitrogenous pelleted diets were formulated, which varied in the particle size of the concentrates (2 and 8 mm, respectively). The objective was to evaluate the effect of different particle sizes of compound diets on performance, nutrient utilisation, gut morphology, and carcass characteristics of fattening Italian White breed rabbits. The finely ground diet led to a significant improvement in feed efficiency and apparent digestibility of crude protein, ether extract, crude fibre and NDF, without any negative effect on gut morphology. Furthermore, a smaller particle size of concentrates in pelleted diets improved carcass traits. Meat colour parameters showed significant differences in longissimus lumborum and biceps femoris due to dietary treatments, but in both muscles pH values 1 h and 24 h after slaughter remained unchanged. It is concluded that a finely ground pelleted diet can be used to improve growth performance of rabbits without affecting carcass parameters.  相似文献   
62.
Freshwater protozoa are poorly characterized in river ecosystems. We report here the richness of the protozoan biotas in relation to environmental gradients from an ecosystematic survey of a large, coastal plain river. Communities were collected from natural and artificial substrates concurrent with water chemistry analysis at 11 sites along the Flint River and Lake Blackshear impoundment. Community similarity, the distribution of collected taxa in functional feeding groups, and the relation of communities to environmental gradients were evaluated. Two principal compenents determined from water chemistry data showed important downstream gradients of decreasing water hardness and increasing nutrient levels. Taxonomic richness was high; 200 to 450 taxa were collected depending on season and collecting technique. Artificial substrates provided the richest collections. Bactivorous species were the vast majority of all taxa collected. Community composition showed an orderly transition from upstream to downstream, and photosynthetic forms were enhanced at nutrient enriched sites. Communities were strongly influenced by increasing nutrient levels. Protozoan community analysis showed that microbial community composition reflects human influences on river ecosystems. Since microbial species exploit detrital resources and respond sensitively to human influences, they can provide important information regarding ecosystem conditions.  相似文献   
63.
The objectives of this study were to assess the relationship between blood lactate variation measured at the plant, and pork quality variation on a large sample size and under commercial preslaughter handling conditions. A total of 600 pigs were randomly chosen on arrival at a commercial slaughter plant and blood samples taken from the ear vein at unloading (UN), after lairage (LA), in the restrainer (RE; before stunning) and at exsanguination (EX) were analysed for lactate content using a Lactate Scout Analyzer (LSA). In order to have a large range of measures, pigs were distributed into two groups; one kept in lairage overnight (G1) and the other for 2 to 3 h (G2) before slaughter. Meat quality was assessed in the Longissimus thoracis (LT), Semimembranosus (SM) and Adductor (AD) muscles by measuring the pH 30 min postmortem (pH1) and at 24 h postmortem (pHu), the colour and the drip loss. Blood lactate levels did not differ between G1 and G2 (P>0.05). A reduced muscle lactate and glucose contents (P=0.02 and P=0.004, respectively) resulting in a lower (P<0.001) glycolytic potential (GP) was observed in the LT muscle of G1 pigs when compared with G2 loins. In the LT muscle of G1 pigs, the lower GP resulted in an increased pHu (r=−0.67; P<0.001), decreased drip loss (r=0.57; P<0.001) and darker colour (r=0.50; P<0.001) compared with G2. In both G1 and G2 pigs, the lower GP was correlated to higher pHu value in the SM and AD muscles (r=−0.73; P<0.001). The greatest correlation was observed in G2 between blood lactate levels at LA and pHu value of the SM and AD muscles (r=0.46 and r=0.44, respectively; P<0.001 for both muscles). The second greatest correlation was found between blood lactate levels at EX and pH1 value in the SM muscle in both groups (r=−0.37 and r=−0.41, respectively; P<0.001 for both groups). Based on the results of this study, it appears that blood lactate levels, as measured by the LSA, reliably reflect the physiological response of pigs to perimortem stress and may help explain the variation in pork quality.  相似文献   
64.
Summary A technical approach, in terms of air quality, implies the review of all components within the air conditioning system and the check of their characteristics, as far as contamination sources are concerned. The contribution introduces the parameters to be examined and specifies the importance of validation.  相似文献   
65.
66.
When dealing with potentially contaminated regions, simple tools are needed to identify in a fast and first approach the areas of the highest concern. In this work we propose a new, intuitive, easy-to-use and versatile tool to accomplish this task. This tool comprises the calculation of a new cumulative index, the Normalised-and-Weighted Average Concentration (NWAC) and its visualisation on a map of the area investigated using a colour based code. The NWAC is a cumulative index that is calculated for each sample using the concentration of freely selected contaminants present in that sample. The NWACs can be used to sort samples in a scale from 0 to 10 according to their contaminant content. A colour-based visualisation of the NWACs on a map facilitates an easy identification of the areas of higher concern within the studied region. The methodology has been exemplified in a case study, for example, the estuary of the Nerbioi-Ibaizabal River (Bilbao, Basque Country) using a representative set of sediments and their metals and metalloids content. The NWAC values obtained have been compared to the corresponding values of mERMq, another cumulative index of general acceptance and frequently used to estimate the toxicity of sediments, with comparable results.  相似文献   
67.
《Process Biochemistry》2014,49(6):973-980
The pseudo-capacitive behaviour of a high surface area carbon veil electrode in a tubular microbial fuel cell (MFC) was investigated as a mechanism to enhance power quality and energy efficiency. Accumulated charge and energy from the anodic biofilm after prolonged open circuit times (1–120 min) were compared against equivalent periods of steady state loading (R = 100–3000 Ω). A significant difference in the amount of accumulated charge with different loads was observed, resulting in 1.051 C (R = 100 Ω) compared to 0.006 C (R = 3 kΩ). The automated application of short open and closed circuit (0.5–10 s) cycles resulted in an increase of power/current production (closed circuit alone), but presented lower efficiency considering entire open and closed period. The cumulative charge on the carbon veil electrode with biofilm was 39,807 C m−2 at 100 Ω. Electrochemical Impedance Spectroscopy (EIS) showed that the Helmholtz layer presented a double layer capacitance of more than ten times the biofilm on electrode. The results indicate that the capacitive behaviour could be utilized to increase the power quality, i.e. its availability/applicability with respect to the operation of low power consuming devices.  相似文献   
68.
Abstract

In this 12th issue of News from the Biological Stain Commission (BSC) under the heading of Regulatory affairs, the Biological Stain Commission’s International Affairs Committee presents information from the meetings of ISO/TC 212/WG 1 Quality and competence in the medical laboratory and ISO/TC 212/WG 3 In vitro diagnostic products both held on 2 – 3 June 2010, plus information on the second plenary meeting of ISO/TC 212 Clinical laboratory testing and in vitro diagnostic test systems held on 4 June 2010. All meetings took place in Seoul, Republic of Korea. Finally, information is provided concerning the 25th meeting of CEN/TC 140 In vitro diagnostic medical devices held on 23 June 2010 in Berlin, Germany.  相似文献   
69.
70.
Sleep and health are closely interrelated and sleep quality is a well-known contributor to perceived health. However, effects of sleep-timing preference i.e. morningness–eveningness on health has yet to be revealed. In this study, we explored the relationship between morningness–eveningness and perceived health in a sample of female working professionals (N?=?202). Sleep-timing preference was measured using the Composite Scale of Morningness. Perceived health was characterized by Center for Epidemiologic Studies Depression Scale, WHO Well-Being Scale-5 and Patient Health Questionnaire-15 scores. We also investigated possible mechanisms, including stress and health-impairing behaviours. In accordance with previous data, we found more depressive mood, lower well-being and poorer perceived health among evening types. To assess health-impairing behaviours we collected data on smoking habits, alcohol consumption, physical activity and diet. Among the possible mechanism variables, greater stress, less frequent physical activity and less healthy diet were associated with eveningness. Furthermore, stress diminished the strength of the association between morningness–eveningness and depressed mood. Physical activity attenuated the strength of the association between morningness–eveningness and well-being. No effects of alcohol consumption could be identified. Our data show that evening preference behaves as a health risk in terms of associating with poor perceived health. Our findings also suggest that this effect might be mediated by health behaviours and stress.  相似文献   
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