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21.
During a German-Brazilian research project on vegetation damage, atmospheric scavenging processes were investigated, considering transport and local emissions. For this goal, radar precipitation data was evaluated together with analyses of fractionated rain samples of one stratiform and one convective rain event. The temporal variation of pollutant concentration in rain water and the meteorological conditions were compared for both rain events at two stations: one at the top of the Serra do Mar mountain ridge ( 900 m) with minor influence of local emissions and one at sea level, close to the high indutrialized area of Cubatao. At the station close to the industrial plants, major influence of the local sources on wet deposition was determined. During the stratiform rain event, an additional influence of transport could be observed. On the top of the Serra do Mar, major influence of the local sources could only be observed during the convective rain event, while transport is mainly responsible for wet deposition during the stratiform event.  相似文献   
22.
To be profitable, producers must reduce diet costs, which can be as high as 80% of the variable costs of an aquaculture expense. As vitamin and mineral premixes represent a significant cost, eliminating addition of these premixes could reduce diet costs if no adverse effects were observed for growth and production parameters. A 105‐day feeding trial was conducted with juvenile Australian red claw crayfish (Cherax quadricarinatus) to evaluate the effects of growth, survival, body composition, processing traits and water quality when red claw were fed a supplemental diet containing 28% crude protein (CP) without vitamin and mineral premixes (and supplemented alfalfa hay) compared with red claw fed a diet (control diet) containing 42% CP, vitamin and mineral premixes, and with supplemented alfalfa hay, and compared with red claw only fed alfalfa hay when grown in ponds. Juvenile red claw (mean weight of 15.7 ± 1.0 g) were randomly stocked into nine 0.02‐ha ponds at a rate of 640 per pond (3.2 per m2), and each treatment was used in three ponds. There were two feedings per day, each consisting of one‐half of the total daily ration. At harvest, individual weight, percentage weight gain, specific growth rate, survival and total yield of red claw fed a control diet was significantly higher (P < 0.05) (83.0 g, 398%, 1.53% day?1, 65.1%,and 1708 kg ha?1 respectively) compared with red claw only fed alfalfa hay (44.9 g, 202%, 1.04% day?1, 30.3% and 431 kg ha?1, respectively), but not different (P > 0.05) from red claw fed the supplemental diet without vitamin and mineral premixes (76.2 g, 367%, 1.47% day?1, 57.2% and 1378 kg ha?1). There were no significant differences (P > 0.05) in feed conversion ratio (FCR) among treatments, which averaged 5.0 (based on prepared diet input). These results indicate that vitamin and mineral supplementation in a diet is not necessary when diet containing 28% CP and alfalfa hay are used in combination for pond grown red claw. These results may help reduce diet costs and possibly increase producers’ profits which might allow for industry expansion.  相似文献   
23.
Light-based analysis is a fundamental approach to quantify the effects of factors determining crop growth in a given environment. The objectives of this study are to confirm the applicability of a digital imagery technique to extract green leaf areas for estimating light interception (LI) of maize canopy and to understand the effect of fertilizer application on the LI and radiation use efficiency (RUE) of maize under various agro-environments in Northern Mozambique. A locally recommended variety, Matuba, was grown in a single season with three different N application rates (0, 30, and 80 kgN ha?1) at one hot/dry low-elevation site, two hot/humid mid-elevation sites, and one cool/humid high-elevation site. Repeated measurements with quantum sensors revealed that the digital imagery is applicable to estimate the LI of maize except for leaf-senescing period close to maturity. The N application demonstrated profitable yield increases with agronomic nitrogen use efficiencies (kg grain yield per kg N input) of 20.6–35.3 kg kg?1 except for the low-elevation site with severe drought stress. In the mid-elevation sites, the yield increases were mostly explained by the improvement of RUE while the effect on LI was small because the vegetative growth was naturally vigorous under high temperatures irrespective of N inputs. At the high-elevation site, the N application improved its stagnant initial canopy development and increased both RUE and LI. The simple and inexpensive imagery technique should be useful to identify physiological basis of maize responses to fertilizer application and its interaction with regional environment even under poorly equipped regions in the tropics.  相似文献   
24.

Objective

To compare the cardiopulmonary effects of low and high doses of fentanyl before and after the correction of bradycardia in isoflurane-anesthetized dogs.

Study design

Prospective, randomized crossover trial.

Animals

Eight healthy male Beagle dogs weighing 11.1 ± 1.3 kg [mean ± standard deviation (SD)] and aged approximately 1 year.

Methods

The dogs were anesthetized with isoflurane [1.3 × minimum alveolar concentration (MAC)] on two occasions and fentanyl was administered intravenously; either low-dose fentanyl, loading dose (33 μg kg–1) and infusion (0.2 μg kg–1 minute–1) or a high-dose, loading dose (102 μg kg–1) and infusion (0.8 μg kg–1 minute–1). Cardiopulmonary variables were measured at three time points in equipotent isoflurane concentrations (1.3 MAC): before fentanyl administration (ISO), during fentanyl-induced bradycardia (ISO–F) and after administration of glycopyrrolate normalized heart rate (ISO–FNHR). Data are mean ± SD.

Results

Heart rate and cardiac index (CI) decreased and systemic vascular resistance index (SVRI) increased at ISO–F in both treatments. Bradycardia and vasoconstriction at ISO–F were greater in high than in low-dose fentanyl (42 ± 7 versus 57 ± 15 beats minute–1 and 3457 ± 1108 versus 2528 ± 968 dyne second cm–5 m–2), respectively. Oxygen delivery index (DO2I) decreased only during high-dose fentanyl. CI and DO2I were higher in both treatments at ISO–FNHR than at ISO–F; however, they were higher only during the high-dose fentanyl than at ISO. SVRI was higher at ISO–F than at ISO and ISO–FNHR in both treatments, and was higher at ISO–F in the high than in the low-dose treatment.

Conclusions and clinical relevance

An overall improvement in cardiovascular function of dogs anesthetized with equipotent isoflurane doses (1.3 MAC) was observed after the treatment of bradycardia only with the high-dose fentanyl.  相似文献   
25.
Cows experiencing high levels of inflammation and specific metabolic conditions tend to have slower follicular growth and lower serum and follicular concentrations of oestradiol (E2). Paraoxonase1 (PON1) activity decreases during inflammatory processes. Therefore, the aim of this study was to evaluate the association between serum and intrafollicular (FF) PON1 activity and the serum and intrafollicular levels of E2 and progesterone (P4), as well as the mRNA expression of genes related to steroidogenesis, metabolism and inflammation in the first post‐partum dominant follicle of Holstein cows. No correlation was found between PON1 activity, the expression of the analysed genes and levels of follicular E2 and P4, except for a negative correlation between serum E2 and follicular PO1 activity. Also, no correlation was found between serum and follicular PON1 during the first post‐partum follicular wave.  相似文献   
26.
27.
The aim of this study was to evaluate the physical, chemical and microbiological quality of the water of the Aroeira River in the city of Silo Mateus, northern region of Espirito Santo State, Brazil, from April 2012 to March 2013, for use in irrigation of vegetable crops. Five points were selected along the river for analysis of pH, chloride (mg/L C1-), total hardness (mg/L CaCO3), dissolved oxygen (mg/L O2), ammoniacal nitrogen (mg/L N-NH3), total iron (mg/L Fe), phosphate/orthophosphate (mg/L PO43-), turbidity (NTU), acidity (mg/L CO2), temperature (℃), electrical conductivity (dS/m), as well as microbiological and parasitological analyses. Only point l, located upstream of the points of domestic sewage discharges, is the closest to be considered suitable for use in irrigation of vegetable crop, demonstrating the possible risks to the health of populations who use water with sewage discharges in urban communities for irrigation of vegetable crops.  相似文献   
28.
The conservation and utilization of allied gene resources is vital for the improvement of crop species. Rubber has been an undeniably beneficial commodity for the past 100 years. Progress in yield improvement over 70 years resulted in primary and hybrid clones with exceptional yielding abilities. The extension of Hevea to marginal areas necessitated breeding of new clones with resistance to environmental constraints. India, China, Brazil, Thailand, Côte d'Ivoire and Vietnam have marginal environments with single or multiple constraints such as low temperature, wind, higher altitude, moisture deficit and diseases. Allied species and accessions from the Brazil Amazonia can be integrated into such breeding programmes. Many of these clones are resultant of natural interspecific hybridizations. Also, allied species are excellent resources of timber. Molecular interventions revealed mtDNA of modern clones are highly conserved contributed by only two clones (PB 56 and Tjir 1). Nuclear DNA is highly divergent due to breeding and selection under varied geo-climates. The adaptation of allied species and wild accessions under a wide range of environments of Brazil is promising as a source of variation for breeding, and enables selection of clones for specific marginal areas.  相似文献   
29.
30.
对68个橡胶无性系1-12树龄的茎围及产量性状进行相关分析的结果显示,第1-6树龄(苗期)和7-12树龄(成龄期)茎围,以及第7-12树龄胶乳产量间的基因型相关系数均达极显著水平.同时,不同树龄之间在苗期茎围(girth A ),成龄期茎围(girth B ),以及橡胶年产量(yield )上的等级相关系数也达到显著水...  相似文献   
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