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11.
Coal mining and agriculture have repeatedly come into conflict when they co‐occur. Although seemingly benign when compared with surface mining, underground coal extraction techniques (including longwall mining) cause subsidence of agricultural land and loss of productivity. Despite growing concerns for global food security and increasing demand for coal resources, there is little peer‐reviewed literature on the impacts of longwall mining in prime agricultural areas. In this paper, we examined the present knowledge of subsidence impacts of longwall mining on agriculture and how this may be interpreted for specific locations such as Australia. The review found that subsidence affects soil properties, hydrology and topography. The main impacts on agriculture are altered soil and groundwater hydrology, modified topography associated with increased erosion or waterlogging risk, and zones of compaction or cracking that cause soil physical and chemical changes. Agricultural productivity is also reduced through altering the types of farming practices that are suited to subsided non‐uniform landscapes, decreasing farming efficiency through increasing paddock heterogeneity and decreasing ease of workability. There is a need to consider these multiple impacts under local conditions, with particular regard to the interaction of mine subsidence‐associated disturbances with farming practices. We conclude by describing future research directions required for Australia and other countries outside of the USA—where most of the research has been conducted. Australia has unique soil and climatic conditions making extrapolation of studies from the USA on subsidence impacts and mitigation problematic. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
12.
Objective— To evaluate the use of sinoscopy for detection and treatment of ventral conchal sinus (VCS) and/or rostral maxillary sinus (RMS) disease in horses.
Study Design— Case series
Animals— Horses (n=60) with suspected paranasal sinus disease.
Methods— Horses were evaluated by sinoscopy through a conchofrontal sinus (CFS) portal with ventral conchal bulla (VCB) fenestration. Other endoscopic sinus approaches and adjunctive diagnostic tests; oral examination, computed tomography, radiography, scintigraphy and endoscopic examination of the upper portion of the respiratory tract were used in some horses.
Results— The CFS approach permitted adequate observation of the RMS and VCS in 53 horses (88%). Hemorrhage caused by VCB fenestration prevented examination of the RMS and/or VCS in 12 horses (21%). Observation of lesions was possible in all horses diagnosed with neoplasia, sinus cysts, and progressive ethmoidal hematomas. Endoscopy of the paranasal sinuses was useful diagnostically in 82% of horses with primary sinusitis. Other diagnostic modalities were usually required to confirm a diagnosis of dental sinusitis.
Conclusions— Trephination into the CFS with VCB fenestration is a minimally invasive technique that provides consistent access to the RMS and VCS. It facilitates diagnosis of many sinus disorders and endoscopically guided treatment of many horses with sinus cysts and primary sinusitis, in combination with sinus lavage.
Clinical Relevance— Many diseases affecting the RMS and VCS can be diagnosed and resolved endoscopically using a CFS approach with VCB fenestration, thus avoiding the need for osteoplastic sinus surgery and its associated risks and complications.  相似文献   
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Background

Large regions of central and eastern Europe are recognized as areas where tick-borne encephalitis virus (TBEV) is endemic, including countries neighbouring Denmark. It is therefore timely and relevant to determine if TBEV infections occur in Denmark. This study investigates the presence of antibodies against TBEV in a cross-section of the Danish canine population to assess the level of exposure to TBEV and possibly identify TBEV microfoci in Denmark.

Methods

Blood samples were collected from 125 dogs originating from five regions of Denmark between November 2005 and March 2006. Serum was tested by indirect ELISA. All positive and borderline samples were re-evaluated by neutralisation test (NT).

Results

The prevalence of TBEV serocomplex antibodies was 30% by ELISA and 4.8% by NT (with 100%-neutralising capacity). The island of Bornholm was the only area in Denmark with NT positive samples.

Conclusions

The island of Bornholm is an area with a high risk of encountering TBEV microfoci. The presence of TBEV serocomplex antibodies in many sentinel animals from other parts of Denmark points toward existence of other TBEV microfoci. Discrepancies found between ELISA and NT results stress the importance of careful evaluation of serological tests, when interpreting results.  相似文献   
15.

Context

Land use changes have modified the extent and structure of native vegetation, resulting in fragmentation of native species habitat. Connectivity is increasingly seen as a requirement for effective conservation in these landscapes, but the question remains: ‘connectivity for which species?’.

Objective

The aim of this study was to develop and then apply a rapid, expert-based, dispersal guild approach where species are grouped on similar fine-scale dispersal behaviour (such as between scattered trees) and habitat characteristics.

Methods

Dispersal guilds were identified using clustering techniques to compare dispersal and habitat parameters elicited from experts. We modelled least-cost paths and corridors between patches and individual movement probabilities within these corridors for each of the dispersal guilds using Circuitscape. We demonstrate our approach with a case study in the Tasmanian Northern Midlands, Australia.

Results

The dispersal guild approach grouped the 12 species into five dispersal guilds. The connectivity modelling of those five guilds found that broadly dispersing species in this landscape, such as medium-sized carnivorous mammals, were unaffected by fragmentation while from the perspective of the three dispersal guilds made up of smaller mammals, the landscape appeared highly fragmented.

Conclusions

Our approach yields biologically defensible outputs that are broadly applicable, particularly for conservation planning where data and resources are limited. It is a useful first step in multi-species conservation planning which aims to identify those species most in need of conservation efforts.
  相似文献   
16.
Acid evokes pain by exciting nociceptors; the acid sensors are proton-gated ion channels that depolarize neurons. The naked mole-rat (Heterocephalus glaber) is exceptional in its acid insensitivity, but acid sensors (acid-sensing ion channels and the transient receptor potential vanilloid-1 ion channel) in naked mole-rat nociceptors are similar to those in other vertebrates. Acid inhibition of voltage-gated sodium currents is more profound in naked mole-rat nociceptors than in mouse nociceptors, however, which effectively prevents acid-induced action potential initiation. We describe a species-specific variant of the nociceptor sodium channel Na(V)1.7, which is potently blocked by protons and can account for acid insensitivity in this species. Thus, evolutionary pressure has selected for an Na(V)1.7 gene variant that tips the balance from proton-induced excitation to inhibition of action potential initiation to abolish acid nociception.  相似文献   
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Climate Change During the Last Deglaciation in Antarctica   总被引:1,自引:0,他引:1  
Greenland ice core records provide clear evidence of rapid changes in climate in a variety of climate indicators. In this work, rapid climate change events in the Northern and Southern hemispheres are compared on the basis of an examination of changes in atmospheric circulation developed from two ice cores. High-resolution glaciochemical series, covering the period 10,000 to 16,000 years ago, from a central Greenland ice core and a new site in east Antarctica display similar variability. These findings suggest that rapid climate change events occur more frequently in Antarctica than previously demonstrated.  相似文献   
20.
Transfection of normal human bronchial epithelial (NHBE) cells with a plasmid carrying the ras oncogene of Harvey murine sarcoma virus (v-Ha ras) changed the growth requirements, terminal differentiation, and tumorigenicity of the recipient cells. One of the cell lines isolated after transfection (TBE-1) was studied extensively and shown to contain v-Ha ras DNA. Total cellular RNA from TBE-1 cells hybridized to v-Ha ras structural gene fragment probes five to eight times more than RNA from parental NHBE cells. The TBE-1 cells expressed phosphorylated v-Ha ras polypeptide p21, showed a reduced requirement for growth-factor supplements, and became aneuploid as an early cellular response to v-Ha ras expression. As the transfectants acquire an indefinite life-span and anchorage independence they became transplantable tumor cells and showed many phenotypic changes suggesting a pleiotropic mechanism for the role of Ha ras in human carcinogenesis.  相似文献   
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