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91.
There is a widespread belief that interaction with an animal is beneficial for the development of children, and several studies (most with methodological shortcomings) have investigated the influence of (companion) animals on the social-emotional and cognitive development of children. In this article, the 1984 model of Professor Jay Belsky has been used to describe which variables influence the development of children and how the companion animal-child interaction influences these variables. The value of the AAA/AAT (Animal Assisted Activities/Animal Assisted Therapy) programmes in children with a wide variety of clinical and social problems, such as behaviour problems and autistic spectrum symptoms, is discussed. The findings suggest that (companion) animals positively influence children's development and have a valuable role in therapy. 相似文献
92.
Commercial fig production is relatively new to the Mediterranean-type climate Western Cape Province of South Africa. A lack of lateral branch development impedes tree structure development and therefore adequate yields of quality fruit. The chemical rest breaking agents, Lift® (thidiazuron 3 g L−1) at 6%, Dormex® (hydrogen cyanamide, 520 g L−1) at 4%, mineral oil at 4% and a combination of mineral oil and Dormex® at 2% each were evaluated in a split plot design in combination with tip-pruning vs. no-pruning to overcome apical dominance and increase complexity (Experiment 1). During the 2008/2009 season, an additional investigation was conducted to evaluate the use of thidiazuron and hydrogen cyanamide for harvest scheduling (Experiment 2). Dormex® at 3% and Lift® at 6%, were applied to dormant trees on 30 June 2008, 3 August 2008, 15 August 2008 or 30 August 2008. In general, Lift® can be used to increase the number of buds breaking in ‘Bourjasotte Noire’ and ‘Col de Damme Noire’, while tip pruning decreased bud break with a resultant increase in shoot length. Dormex® and oil combined decreased bud break in these two cultivars but was effective on ‘Noire de Caromb’. Where bud break was increased the resultant N + 1 shoot length was decreased. RBAs increased the number of fruit in both the breba and main crop of ‘Noire de Caromb’, but decreased fruit size of the breba crop. Our data are not conclusive as to what the reason for low lateral bud break might be but leans towards strong AD in seasons with 400 Utah CU or more, but might include some delayed foliation response in seasons with less than 200 Utah CH. 相似文献
93.
T Révay A Kovács GA Presicce W Rens I Gustavsson 《Reproduction in domestic animals》2003,38(5):377-379
In order to identify X‐ and Y‐bearing spermatozoa in water buffalo by fluorescence in situ hybridization (FISH), some available probes of closely related species were examined. An X‐ and Y‐specific probe set, made from flow sorted yak chromosomes, labelled in somatic metaphases of water buffalo the whole X and Y, respectively, except their centromere regions. A cattle Y‐chromosome repeat sequence (BC1.2) showed strong signal on the telomere region of the buffalo Y‐chromosome, demonstrating the evolutionary conservation of this locus in water buffalo. In hybridization experiments with spermatozoa from five buffaloes, the yak X‐Y paint set demonstrated clear signals in more than 92% (46.8% X and 45.8% Y) of the cells. Using the cattle Y‐chromosome specific BC1.2 probe, clear hybridization signal was detected in more than 48% of the cells. Statistical analysis showed that there was no significant difference between bulls or from the expected 50 : 50 ratio of X‐ and Y‐bearing cells. The probes presented here are reliable to assess separation of X‐ and Y‐bearing spermatozoa. 相似文献
94.
Valentina Matiller Gustavo J. Hein Antonela F. Stassi Emmanuel Angeli Eduardo M. Belotti Hugo H. Ortega Florencia Rey Natalia R. Salvetti 《Reproduction in domestic animals》2019,54(1):46-54
The objective of this study was to examine the expression of transforming growth factor beta receptor (TGFBR)1, TGFBR2, TGFBR3, activin receptor (ACVR)1B and ACVR2B in ovaries of cows with cystic ovarian disease (COD). The expression of the selected receptors was determined by immunohistochemistry in sections of ovaries from cows with ACTH‐induced and spontaneous COD. Expression of TGFBR1 and TGFBR3 was higher in granulosa cells of cysts from cows with spontaneous COD than in tertiary follicles from the control group. Additionally, TGFBR3 expression was higher in granulosa cells of cysts from cows with ACTH‐induced COD than in those from the control group and lower in theca cells of spontaneous and ACTH‐induced cysts than in tertiary control follicles. There were no changes in the expression of TGFBR2. ACVR1B expression was higher in granulosa cells of tertiary follicles of cows with spontaneous COD than in the control group, whereas ACVR2B expression was higher in cysts of the spontaneous COD group than in tertiary follicles from the control group. The alterations here detected, together with the altered expression of the ligands previously reported, indicate alterations in the response of the ligands in the target cells, modifying their actions at cellular level. 相似文献
95.
Petra Lehnik-Habrink Sebastian Hein Tin Win Wolfram Bremser Irene Nehls 《Journal of Soils and Sediments》2010,10(8):1487-1498
Purpose
Analyzing organic pollutants in forest soil is challenging because they are strongly physical and chemical bound to soil organic matter (SOM). Within the framework of a forest soil inventory, an analytical protocol for the determination of polycyclic aromatic hydrocarbons (PAH), polychlorinated biphenyls (PCB), and organochlorine pesticides (OCP) should be established and validated using one and the same extraction and cleanup procedure. The protocol should be applicable for reliable analysis of a high number of samples in a short timeframe.Materials and methods
Two different soil samples representative for the humic layer from a typical mixed and coniferous forest soil had been used for the analysis. Three solvents of different polarity, namely cyclohexane (CH), ethylacetate (EA)/CH (1/1, v/v), and acetone (AC)/CH (2/1, v/v), and the six standard extraction techniques (pressurized liquid extraction (PLE), soxhlet extraction, fluidized bed extraction, sonication, shaking, and one-step extraction recommended for analyzing agricultural soil in Germany (VDLUFA 2008)) were compared concerning their extraction efficiency. For additional matrix separation, two different cleanup procedures (gel permeation chromatography (GPC) and solid-phase extraction (SPE) with different sorbents) were tested. Quantification was carried out using gas chromatography combined with mass spectrometry (GC–MS) and two different injection systems (split/splitless injection and programmable temperature vaporizer (PTV) injection). Labeled internal standards, added prior to extraction, were used for method evaluation.Results and discussion
For the simultaneous extraction of PAH, PCB, and OCP from organic forest soil PLE with acetone/cyclohexane (2/1, v/v) provided the highest extraction efficiency. A two-step cleanup procedure consisting of GPC followed by SPE with silica gel was entirely sufficient for the separation of humic substances without discrimination of analytes. Recovery rates for the different extraction and cleanup steps ranged between 89% and 106%. For quantification, a GC–MS method was developed using two different injection systems and two capillary columns of different selectivity.Conclusions
By comparing six standard extraction techniques for PAH, PCB, and OCP from forest soil, we obtained the highest extraction efficiency when using PLE with AC/CH (2/1). For sample injection, we achieved best results using an optimized PTV injection system as it highly reduced the breakdown of thermolabile pesticides. Using this combination of technical equipment, it is possible to determine a concentration of the analytes in the trace level range of 1–2 μg kg?1 in humic soil. 相似文献96.
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Models of binary outcomes are commonly used in forestry, but the predictions errors of these types of models are difficult
to present effectively. In addition, most studies generally use a fixed value of 0.5 as the separation between events and
non-events. The use of cutpoint analysis has been widely utilized in the health sciences and other fields, while it is relatively
uncommon in the forestry literature. Cutpoint analysis involves locating the optimal value that minimizes prediction errors
associated with binary outcomes. This case study illustrates the use of cutpoint analysis to improve a dynamic model of individual
branch mortality. In this study, the use of cutpoint analysis increased the model specificity (prediction of events) from
77.8% (standard cutpoint of 0.5) to 90.3% (optimal cutpoint of 0.672). At the same time, the sensitivity of the model decreased
only slightly and the false positive rate (non-event predicted as an event) was greatly decreased from 22.2 to 9.7%. In addition,
the use of receiver operating characteristics (ROC) curves was an effective approach for evaluating prediction errors of models
of binary outcomes. Cutpoint analysis is a simple yet effective method for improving predictions of binary outcomes and should
be used more regularly, particularly when modelling the binary outcome of rare events such as mortality. 相似文献