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Summary In order to plan and optimize forest production reliable fundamentals must be made available. Yield tables are the base for yield prognosis and plannings and have to be apportioned according to the top-height of trees and increments within a wide range of thinning degree. Furthermore they should allow to derive the yield by diameter classes and assortments of stand volumes and thinning yields. In one word what we need are “structure yield tables”. Stand tables of this kind are, beside site yield tables, in nascent stage at the institute of yield science in Munich. In order to derive increments preference should be given to the figures of well fitted stand tables over the results of local increment borings or measurements taken on permanent circular sample areas. Plannings which comprise the area of a whole country require large area inventories which have to be completed by inventories for smaller units. In future, research in the field of yield science should be done within the scope of an ecosystem research in close cooperation with adjacent disciplines. We still do not know enough about appropriate planting spaces. There is a strong need to close this gap in our knowledge as soon as possible. Research activity should be extended to growing species outside of the forests in order to ease a modern landscape tanding.   相似文献   
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Retention of aging ewes is a strategy producers may use to maintain or increase flock size. Older ewes can have a higher risk of mortality and health issues, but these may be minimised with early intervention and culling. This retrospective study examined the incidence and causes of mortality and culling in a flock of Merino ewes as they aged from 4.5 to 5.5 until 9.5 to 10.5 years. The annual rate of ewe mortality ranged from 6.2% to 9.9%, with lambing complications being the major source of reported loss. Annual culling rates ranged from 1.6% to 42.8%, the larger rates reflecting opportunistic replacement with younger ewes rather than essential culling to maintain welfare and productivity. The major reasons for culling were low condition score, worn or missing teeth or faulty udders. The incidence of other faults was low. Only 18.3% of ewes remained when aged 9.5–10.5 years and these were fertile (89% pregnant) with a high proportion of multiple fetuses (52%) in their final year, although fleece weight had declined. Younger ewes born in 2004/2005 tended to have lower annual mortality rates than the aged ewes, but 8%–12% were still culled annually. It is concluded that an annual inspection pre-joining of all ewes and preventative culling for health issues is necessary to minimise any increase in mortality and risk to ewe welfare from retaining aging ewes. More frequent inspection will be required as potential health issues develop during the year, as these may not be evident pre-joining.  相似文献   
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Brucella suis is an emerging, zoonotic disease predominantly affecting dogs and humans that engage in feral pig hunting in Australia and other countries. Although B. suis infection in dogs shares some clinical similarities to the host-adapted species (B. canis), B. suis remains an incompletely understood pathogen in dogs with limited published data on its pathogenesis and clinical features. This case series describes the presentations, diagnosis, and clinical management of B. suis infection in three dogs: (1) a bitch with dystocia, abortion and mastitis; (2) an entire male dog with septic arthritis and presumptive osteomyelitis; and (3) a castrated male dog with lymphadenitis. Unique features of these cases are reported including the first documented detection of B. suis from milk and isolation from lymph nodes of canine patients, as well as the follow-up of pups born to a B. suis-infected bitch. Consistent with previous reports, all three dogs showed a favourable clinical response to combination antibiotic therapy with rifampicin and doxycycline. Individually tailored drug regimens were required based on the clinical presentation and other factors, including owner expectations and compliance with therapy as well as a zoonotic risk assessment (generally considered low, except around time of whelping). The authors include their recommendations for the clinical management of dogs that are at-risk or seropositive for B. suis with or without clinical signs or laboratory-confirmed infection.  相似文献   
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An efficient, copper-based catalyst has been discovered that oxidizes a wide range of alcohols into aldehydes and ketones under mild conditions. This catalytic system utilizes oxygen or air as the ultimate, stoichiometric oxidant, producing water as the only by-product.  相似文献   
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CASE HISTORY: A 6.2 kg, 8-year-old, spayed female Australian Terrier was presented with weight loss, inappetence, lethargy and a 2-day history of intermittent vomiting.

CLINICAL FINDINGS: The dog had cranial abdominal pain and there was melaena present on digital rectal examination. Haematology revealed a marked, acute leucogram.

DIAGNOSIS AND TREATMENT: Fasting serum gastrin levels were markedly elevated and gastrinoma was suspected. Treatment was initiated with omeprazole, ranitidine and sucralfate. The dog remained clinically normal for 26 months, at which time exploratory surgery was undertaken and the dog subsequently euthanised due to extensive metastases. Histopathology and immunocytochemistry confirmed the diagnosis of metastatic gastrinoma.

CLINICAL RELEVANCE: This is a rare condition infrequently reported. Although the number of cases treated with omeprazole are too few to draw firm conclusions, it would appear that proton pump inhibitors are useful and should be considered for cases of gastrinoma managed medically. Long-term prognosis is poor, and survival times range from 1 to 147 weeks. Many treatment options are discussed in the medical literature though not all are feasible in veterinary patients.  相似文献   
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Invertebrates play important roles in ecosystem functioning, but with the decline in biodiversity worldwide, it has become increasingly evident that our knowledge of invertebrate diversity distributions and of how to adequately integrate many invertebrates into conservation strategies is insufficient. We analyzed congruence between patterns of total as well as of endemic species richness of twelve invertebrate taxa across Europe and compared these patterns to those of so far predominantly studied vertebrates and plants. Coarse-scale centers of high collective diversity were identified, all in southern European regions. However, the strength of covariation between diversity patterns strongly depended on the respective taxa, with ground beetles emerging as one of the invertebrate taxa significantly reflecting endemism and total species richness distributions of many invertebrates, vertebrates and plants. Plants and ants showed similarly strong cross-taxon correlations. In contrast, correlations of vertebrates with invertebrates were in part less strong, questioning whether conservation strategies based on the former adequately account for diversity of invertebrates as a whole. Moreover, as the potential impact of environmental factors on diversity distributions varies among taxa, future climate change might affect relationships between richness patterns of different taxa. Our findings draw attention to the necessity of incorporating invertebrates, represented for instance by the highly diverse ground beetles, into national and international conservation decisions. They also highlight the importance of individual countries in maintaining European biodiversity and the responsibility of these countries for specific invertebrate taxa within international conservation frameworks, emphasizing the need for adequate consideration of invertebrates in the implementation of conservation actions.  相似文献   
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