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31.
Pesticide use in developing countries increases rapidly. In many regions, we miss knowledge of how frequently pesticides are applied and which active ingredients are used. We present a new cost-efficient and rapid assessment method of recording pesticides diversity in rice-dominated landscapes and present some evidence of the misuse of active ingredients in our study regions. We investigated 17 rice fields in two regions of Northern Vietnam in 2014 and 2015. At each region, we explore the abundance of pesticides used with three methods including (1) the novel approach of collecting pesticide packages close to our target rice fields, (2) observations of farmers spraying pesticides in the surrounding and (3) interviewing local farmers. By collecting pesticide packages, we found 811 packages containing 74 different active ingredients. On average, 19 active ingredients (ranging from four to 40 active ingredients) were applied with an average content of 275.3 g of active ingredients per site. Insecticide packages (39%) were most abundant followed by those of fungicides (31%), herbicides (16%) and other active ingredients (14%). On all sites, active ingredients banned in the European Union were applied by the farmers. Collecting pesticide packages proved to be an efficient and rapidly implemented method to obtain some baseline information about pesticide application (for Northern Vietnam). We suspect that improved agricultural extension services could contribute to good agricultural practices in pest management. Generally, better information and education for local farmers for appropriate use of pesticides seem a necessity.  相似文献   
32.

Objectives

To compare propofol and alfaxalone, with or without midazolam, for induction of anesthesia in fentanyl-sedated dogs, and to assess recovery from total intravenous anesthesia (TIVA).

Study design

Prospective, incomplete, Latin-square study.

Animals

Ten dogs weighing 24.5 ± 3.1 kg (mean ± standard deviation).

Methods

Dogs were randomly assigned to four treatments: treatment P-M, propofol (1 mg kg?1) and midazolam (0.3 mg kg?1); treatment P-S, propofol and saline; treatment A-M, alfaxalone (0.5 mg kg?1) and midazolam; treatment A-S, alfaxalone and saline, administered intravenously (IV) 10 minutes after fentanyl (7 μg kg?1) IV. Additional propofol or alfaxalone were administered as necessary for endotracheal intubation. TIVA was maintained for 35–55 minutes by infusions of propofol or alfaxalone. Scores were assigned for quality of sedation, induction, extubation and recovery. The drug doses required for intubation and TIVA, times from sedation to end of TIVA, end anesthesia to extubation and to standing were recorded. Analysis included a general linear mixed model with post hoc analysis (p < 0.05).

Results

Significant differences were detected in the quality of induction, better in A-M than A-S and P-S, and in P-M than P-S; in total intubation dose, lower in P-M (1.5 mg kg?1) than P-S (2.1 mg kg?1), and A-M (0.62 mg kg?1) than A-S (0.98 mg kg?1); and lower TIVA rate in P-M (268 μg kg?1 minute?1) than P-S (310 μg kg?1 minute?1). TIVA rate was similar in A-M and A-S (83 and 87 μg kg?1 minute?1, respectively). Time to standing was longer after alfaxalone than propofol, but was not influenced by midazolam.

Conclusions and clinical relevance

Addition of midazolam reduced the induction doses of propofol and alfaxalone and improved the quality of induction in fentanyl-sedated dogs. The dose rate of propofol for TIVA was decreased.  相似文献   
33.
Ketamine HCl [2-(o-chlorophenyl)-2-(methylamino) cyclohexanone HCl] concentrations in whole blood were used to study the pharmacokinetics of i.v., i.m., and rectal administrations, at a dose of 25 mg/kg, in normal domestic cats. Absorption was rapid with both the i.m. and rectal routes. Systemic availability was 51% (SEM 10) for the i.m. dose and 43.5% (SEM 6.1) for the rectal dose. The first-pass effect had a minimal influence on the metabolism of ketamine HCl administered rectally. The elimination rate constant (beta) of the drug was statistically similar in the i.v., i.m., and rectal groups, at a 95% level of significance (P less than 0.05). At the dosage rates studied, ketamine HCl produced an anesthetic effect in the cat following i.v., i.m. and rectal administration.  相似文献   
34.
A tone ending in unavoidable electric shock was periodically presented to pigeons while they pecked a key for food. When pecking was completely disrupted by tone, shock was disconnected, and the training tone and tones having new frequencies were presented. Initially the gradient of generalization was broad; as testing proceeded, however, the gradient narrowed severely.  相似文献   
35.
Swine Hepatitis E virus (HEV) can be transmitted from pigs to humans causing hepatitis. A high prevalence of HEV in wild boar populations is reported for several European countries, but actual data for Germany are missing. During the hunting season from October to December 2007 liver, bile and blood samples were collected from wild boars in four different German regions. The samples were tested for HEV RNA by quantitative PCR (qPCR) and anti-HEV IgG antibodies by two different ELISAs and a Line immunoassay. A seroprevalence of 29.9% using ELISA and 26.2% in the Line immunoassay was determined. The seroprevalence rate varied greatly within the analyzed regions. However, qPCR analysis revealed a higher prevalence of 68.2% positive animals with regional differences. Surprisingly, also adult wild sows and wild boars were highly HEV positive by qPCR. Compared to liver and serum samples, bile samples showed a higher rate of positive qPCR results. Sequencing and phylogenetic analysis of a 969 nt fragment within ORF 2 revealed that all isolates clustered within genotype 3 but differed in the subtype depending on the hunting spot. Isolates clustered within genotypes 3i, 3h, 3f and 3e. Within one population HEV isolates were closely related, but social groups of animals in close proximity might be infected with different subtypes. Two full-length genomes of subtypes 3i and 3e from two different geographic regions were generated. The wild boar is discussed as one of the main sources of human autochthonous infections in Germany.  相似文献   
36.
Silicon-based quantum dots were intraperitoneally injected in individuals of Carassius auratus gibelio. Their effects on white muscle were investigated by following their distribution and impact on the antioxidative system. The GSH level significantly increased after 1 and 3?days of exposure by, respectively, 85.3 and 25.4%. Seven days later, GSH levels were similar to control concentrations. MDA concentration rose after three days by 46.9% and remained at the same level after 7?days. Protein thiol levels significantly decreased by 6.7 and 8.1% after 3 and 7?days, whereas advanced oxidation protein products increased by 12.7, respectively, 28.1% in the same time intervals. The protein reactive carbonyl groups were raised only after the first day of exposure and returned to the control level later on. SOD specific activity increased up to 48% after 7?days, while CAT activity increased by 328, 176, and 26% after 1, 3, and 7?days of treatment. GST specific activity was up-regulated by 87, 18, and 9%, while GR activity increased by 68, 34, and 9%. G6PD activity was up-regulated by 12, 22, and 50%, whereas GPx activity raised by 75 and 109% compared to control after, respectively, 1, 3, and 7?days. Our results suggest that oxidative stress induced by silicon-based quantum dots was not strong enough to cause permanent damage in the white muscle of crucian carp.  相似文献   
37.
Book reviews     
Marilyn Holly is an Associate Professor of Philosophy at the University of Florida. Her special interests include political philosophy, ethics and ecology, Jungian thought, and Native American spirituality in its relation to the environment. She is currently at work on a monograph-length piece on the latter topic. She has taught an undergraduate course in ethics and ecology, and plans to do so again. The following essay emerged from her search for a suitable text for such a course.  相似文献   
38.
The objective of this study was to examine the potential of Solanum scabrum to provide a colorant for food. We conducted a field trial with eight accessions from four different sources and recorded both morphological variability and fruit yield differences between accessions. Further, anthocyanin and glucoalkaloid concentrations were determined. The accessions could be assigned to two distinct groups: a leafy vegetable type with toxic fruits used in Africa and a berry type with edible fruits known as Garden Huckleberry in North America, but both types had edible leaves with low glucoalkaloid concentrations. The leafy vegetable type set not much fruit. In contrast, the berry type yielded on average 800–900 g berries per plant with remarkable high anthocyanin concentrations of 8.1–13.9 g kg−1 fresh weight, calculated as petunidin 3-p-(coumaryl-runtinoside)-5-glucoside. Thus, S. scabrum can serve as a source for natural anthocyanin pigments. In particular, two accessions with a high fruit yield were promising candidates as a berry crop. One had the best anthocyanin concentration of the examined material and the other one had a low percentage of unripe berries as a further advantage.  相似文献   
39.
40.
Effects of fire on the functioning of the soil microbial community are largely unknown. In this study, we addressed the charcoal mineralisation potential of microbial inocula extracted from burned and unburned soil. The mineralisation of charcoal was analysed during a 1 month incubation experiment under controlled conditions with and without substrate addition. The aim of the study was to elucidate (1) the indirect effect of fire on the functioning of the soil microbial community in terms of charcoal degradation and (2) the possibility to stimulate this degradation by addition of two substrates of increasing complexity. Our conceptual approach included the monitoring of CO2 emission from microcosms containing laboratory-made charcoal and microbial inocula from burned and unburned soil with and without 13C labelled glucose and cellulose.Our results showed higher charcoal mineralisation without substrate addition in microcosms with the inocula from unburned soil compared to burned soil. Charcoal mineralisation was stimulated by the addition of glucose, whereas cellulose addition did not induce a priming effect. We observed a higher stimulation of charcoal mineralisation induced by glucose for the inoculum from burned soil compared to the inoculum from unburned soil. We concluded that fire did affect the functioning of the soil microbial community in terms of charcoal degradation and that the important priming effect induced by glucose may be explained by an increase of the overall microbial activity, rather than selective stimulation of charcoal degrading microbial communities.  相似文献   
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