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51.
Andreas Gruber Jolanda Zimmermann Gerhard Wieser Walter Oberhuber 《Annals of Forest Science》2009,66(5):503-503
52.
SM Gonzalez CB da Silva AG Lindquist I Bufalo F Morotti LA Lisboa M Seneda 《Reproduction in domestic animals》2017,52(5):836-841
The goal of this study was to determine the distribution of pre‐antral follicles in the ovarian parenchyma of mares. For Experiment 1, each ovary was cut longitudinally at the greater curvature, performing two hemiovaries. After that, six fragments from each hemiovary were obtained, resulting in 12 fragments, which were divided into the innermost region of the parenchyma, the middle region and the outermost region. All the three obtained sections were cut transversally to obtain two fragments from each one. For Experiment 2, each ovary also submitted to a longitudinal cut on the greater curvature, forming two hemiovaries. Each hemiovary was sectioned into four symmetrical fragments, resulting in eight fragments per ovary. The fragments were related as being near to or far from the ovulatory fossa. The fragments of both experiments were immediately fixed in Carnoy for 12 hr and kept in 70% ethanol for 24 hr. Follicles were classified according to the stages of development and for morphological integrity according to oocyte morphology and granulosa cells. After the histological assessment, a total of 1,130 follicles were visualized from Experiment 1, being 1,054 (93.3%) primordial follicles and 76 (4.7%) follicles in development. The innermost region had the highest percentage of pre‐antral follicles compared to the other regions (p < .05). The middle and outermost regions showed higher percentages of intact primordial and developing follicles than the innermost region (p < .05). Considering Experiment 2, 938 follicles were found, being 894 (95.3%) primordial and 44 (4.7%) follicles in development. The region near the ovulatory fossa presented higher (58.7%; 551 of 938) follicular concentration compared to the region far from the ovulatory fossa (41.3%; 387 of 938; p < .05). As a conclusion, distribution of pre‐antral follicles in the equine ovary has a specific pattern through the parenchyma. Also, the follicular integrity differed in the studied ovarian areas. 相似文献
53.
Longtime effects of deep groundwater extraction management on water table levels in surface aquifers
Purpose
A longtime monitoring (2003–2013) of groundwater levels and soil moisture was done in a plain tract surrounded by deposits from the Saale glacial stage in northern Germany. The purpose was to document the changes in the soil water regime over time in relation to changes in management of groundwater extraction and to evaluate if the hitherto management has been suitable for plant water supply for the local grassland production.Materials and methods
Groundwater wells in the surface aquifer were monitored at 11 survey sites, and soil matric potentials were measured with tensiometers at five depths per site. Soil analyses also were done. This report contains the results from three of the 11 survey sites, which best represent the variability of the soils in the area.Results and discussion
The monitoring showed that groundwater extraction from deep aquifers via individual wells altered the groundwater levels in the surface aquifer, even though there was a distance of several meters depth and a geological parting between the two aquifers. The impact of the groundwater extraction was shown by significant correlations between groundwater levels in the surveyed soils and groundwater extraction rates of individual wells. Climatic factors only affected groundwater levels in individual years. The management of the groundwater extraction from 1977 to 2006 severely lowered the groundwater level in the surface aquifer. Due to a limitation of the groundwater extraction rates and a shift in the degree of capacity utilization of the individual wells from 2006 onward, groundwater levels in the area are recovering. Correspondingly, the contribution of capillary rise to plant water supply has increased within the monitoring period.Conclusions
The monitoring proves that the present management of groundwater extraction is more suitable for the groundwater situation than past management. However, groundwater levels have not yet obtained a new equilibrium, so continual monitoring is needed.54.
Karin L. Zimmermann Ivo A. Van Der Lans 《The Journal of Horticultural Science and Biotechnology》2013,88(6):7-12
SummaryThis paper describes an integrated project approach that forms the basis of the studies on consumer-driven innovative and responsive supply chains in ISAFRUIT Pillar 1. This integrated approach leads to a wide range of in-depth results on trends, preferences, and innovativeness of the European consumer in the context of fruit, and on product innovation, chain innovativeness, and transition strategies for the European fruit industry. Differences in, for instance, preferences for different fresh, prepared, and processed fruit products across consumers and across consumption situations, and differences in consumer innovativeness in the context of novel fruit products, lead towards a cross-cultural European segmentation and a variety of consumer-driven fruit chain strategies to valorise the added value of fruit products. Inputs from social, natural, and technical sciences are combined to optimise true consumer-driven innovativeness. 相似文献
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Using a partial sanitation method "Enzootic Pneumonia" (EP) could be eradicated in 17 EP-reinfected pig breeding herds. Partial sanitation includes separation measures in form of a piglet and gilt free interval on one side and as an additional protection against reinfection the temporary feeding of a medicated diet on the other side. Frequent herd controls for several years as well as mixed fattening experiments with carcass examination combined with milk and blood serology served as criteria for the sanitation success. From these results it is concluded that the infection pathway of EP is mainly maintained by young animals in the herd. Contrary to total sanitation, which will amount to at least sFr. 720 per sow, partial sanitation will only cost between sFr. 40-170 per sow, depending on herd size. Therefore, partial sanitation may be regarded as a full alternative to total sanitation after an outbreak of EP. 相似文献
59.
Tree water deficit estimated by measuring water-related changes in stem radius (DeltaW) was compared with tree water deficit estimated from the output of a simple, physiologically reasonable model (DeltaWE), with soil water potential (Psisoil) and atmospheric vapor pressure deficit (VPD) as inputs. Values of DeltaW were determined by monitoring stem radius changes with dendrometers and detrending the results for growth. We followed changes in DeltaW and DeltaWE in Pinus sylvestris L. and Quercus pubescens Willd. over 2 years at a dry site (2001-2002; Salgesch, Wallis) and in Picea abies (L.) Karst. for 1 year at a wet site (1998; Davos, Graubuenden) in the Swiss Alps. The seasonal courses of DeltaW in deciduous species and in conifers at the same site were similar and could be largely explained by variation in DeltaWE. This finding strongly suggests that DeltaW, despite the known species-specific differences in stomatal response to microclimate, is mainly explained by a combination of atmospheric and soil conditions. Consequently, we concluded that trees are unable to maintain any particular DeltaW. Either Psisoil or VPD alone provided poorer estimates of DeltaW than a model incorporating both factors. As a first approximation of DeltaWE, Psisoil can be weighted so that the negative mean Psisoil reaches 65 to 75% of the positive mean daytime VPD over a season (Q. pubescens: approximately 65%, P. abies: approximately 70%, P. sylvestris: approximately 75%). The differences in DeltaW among species can be partially explained by a different weighting of Psisoil against VPD. The DeltaW of P. sylvestris was more dependent on Psisoil than that of Q. pubescens, but less than that of P. abies, and was less dependent on VPD than that of P. abies and Q. pubescens. The model worked well for P. abies at the wet site and for Q. pubescens and P. sylvestris at the dry site, and may be useful for estimating water deficit in other tree species. 相似文献
60.
M. Zimmermann und Hanz Petzysch 《Journal of pest science》1963,36(1):14
Ohne Zusammenfassung 相似文献