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101.
Forests are dynamic ecosystems, spatial mosaics of localized disturbances and regenerating vegetation. Following forest conversion to human land uses, expanding forest cover follows four different modes of reforestation: (a) spontaneous natural regeneration; (b) assisted natural regeneration; (c) agroforestry; and (d) commercial tree plantations. Natural regeneration fundamentally depends on the alignment of ecological and social factors at landscape scales. A deeper socioecological understanding of reforestation in the tropics will lead to the development of effective policies and governance structures that enhance forest cover and ecosystem services, protect biodiversity, and improve forest-dependent livelihoods.  相似文献   
102.
103.
Otodectes cynotis infestation is common in kittens housed in crowded environments like animal shelters. It is unknown how rapidly O cynotis is killed within the first 72h of treatment with currently available products. Kittens ≥4 weeks of age with live O cynotis in both ears (AU) were administered 0.5ml of 0.01% ivermectin otic suspension (Acarexx; Idexx Pharmaceuticals) once, AU or selamectin (Revolution; Pfizer Animal Health) once, on the skin following the manufacturer's instructions. Repeat microscopic examination was performed on individual ears based on a randomization schedule during the 72h after treatment. There was no evidence of toxicity with either drug and administration of 0.01% ivermectin significantly reduced the time to live mite-free status compared to selamectin. Both drugs have an effect against O cynotis as early as 10-12h after administration with an increasing effect over time.  相似文献   
104.
We applied capture–recapture methodology (CRC) to data from three surveillance sources (statutory notification, abattoir survey (AS) and fallen stock (FS) survey) to estimate the number of holdings infected with scrapie in Great Britain and to assess the sensitivity of the surveillance network. Between January 1, 2002 and March 31, 2003, 144 holdings were identified by the three sources. Using CRC modelling techniques, we estimated a minimum lower bound for the total number of holdings infected as 642. A biologically plausible positive dependence between the statutory reporting and the fallen stock survey was found statistically significant. The sensitivity of the three sources combined was very low. The integration of the three overlapping sources provided a better understanding of the interactions within the surveillance network. However, the scarcity of the data and reduced overlapping among sources only allowed for very cautious inferences to be drawn about the true proportion of scrapie affected holdings in the national population. Future surveys and surveillance activities should be planned such that the resulting data can be used more effectively as part of CRC modelling approaches.  相似文献   
105.
ObjectiveTo collect data about the current practice of recovering horses from general anesthesia and recovery personnel safety.Study designOnline survey.MethodsAn online questionnaire, including questions on general demographic data, recovery drugs, modality and characteristics of equine recovery and morbidity and mortality, was designed and distributed via e-mail to equine practitioners worldwide.ResultsPractitioners from 22 countries completed 373 questionnaires; 53% of the participants were board-certified equine surgeons, and the remainder were board-certified anesthesiologists (18%), large animal residents (8%), general practitioners (7%), large animal interns (6%), anesthesia residents (4.5%) and veterinary technicians (1.6%). Respondents were employed by academia (58%) or private practice (42%). Of the respondents employed at a university, 93% had a board-certified anesthesiologist on staff compared with 7% of respondents employed at a private practice. Most of the respondents assist horses during recovery, with 23% assisting every recovery and 44% assisting recovery in the majority of cases. Reasons for choosing to assist horses during recovery were: orthopedic procedures (57%), neurological deficits (49%), bad health (47%), history of poor recovery (44%), foals (42%), draft breeds (30%), magnetic resonance imaging (17%) and computed tomography (16%). Unacceptable recoveries were reported by 77% of participants. Commonly reported complications during recovery with any method were: orthopedic injury (66%), myopathy (54%), skin abrasion (53%) and airway obstruction (37%). The incidences of unacceptable quality of recovery (p = 0.09) or personnel injury (p = 0.56) were not different between assisted and nonassisted recoveries; however, more equine fatalities were reported for assisted recoveries (p < 0.006). Practitioners in academia reported more unacceptable recoveries (p < 0.0007) and personnel injuries (p < 0.002) compared with those in private practice.ConclusionsThe method of recovery differs among hospitals. Recovery personnel injuries associated with assisting horses during recovery are an important and previously unreported finding.  相似文献   
106.
Although tropical forest conservation is a top priority for human and environmental health, deforestation persists, mainly because of food and economic needs. No community will totally give up economic activities for the sake of ecological integrity, unless it is given alternative economic activities from which to draw its livelihood. Beekeeping in the forest buffer zone instead of traditional destructive honey-harvesting from forest trees is one such option at Arabuko Sokoke Forest (ASF) in Kenya. ASF is a dry coastal forest which is home to endangered and threatened fauna and is a hotspot considered a priority for conservation. In order to find out whether honey quantity and quality differed with distance from the forest, we studied honey yield per harvest (kg) and obtained samples from hives placed at varying distances from ASF in two successive years. Honey yield increased with proximity to the forest. Indeed the yield almost doubled in hives placed less than 1 km from the forest compared to those placed more than 3 km from the forest. All the honey samples met internationally required quality standards, although sugar levels were at the lower limit. This study demonstrates that the conservation of tropical forest ecosystems can have real local economic benefits. The documentation of the services provided by nearby natural areas should help make conservation of these areas a priority, even for the local communities.  相似文献   
107.
ObjectiveTo determine the specific lung elastance (SEL) in anesthetized dogs and to evaluate the efficacy of a SEL-based recruiting airway pressure (RPaw) at improving global and regional lung aeration.Study designRetrospective and prospective clinical study.AnimalsA total of 28 adult dogs were included in the retrospective study and six adult dogs in the prospective study.MethodsRetrospective study: SEL and SEL-based RPaw were determined using previously published data. In mechanically ventilated dogs undergoing thoracic computed tomography (CT), SEL was calculated as ΔPL/(VT/EELV), where ΔPL is the driving transpulmonary pressure, VT is the tidal volume and EELV is the end-expiratory lung volume. The ratio of lung to respiratory system elastance (EL/Ers) was determined. SEL and EL/Ers were used to calculate the SEL-based RPaw. Prospective study: dogs underwent thoracic CT at end-expiration and at end-inspiration using the SEL-based RPaw, and global and regional aeration was determined. For analysis of regional aeration, lungs were divided into cranial, intermediate and caudal regions. Regional compliance was also calculated. A p value <0.05 was considered significant.ResultsThe SEL and EL/Ers were 12.7 ± 3.1 cmH2O and 0.54 ± 0.07, respectively. The SEL-based RPaw was 29.1 ± 7.6 cmH2O. In the prospective study, the RPaw was 28.2 ± 1.3 cmH2O. During RPaw, hyperinflation increased (p = 0.0003) whereas poorly aerated (p < 0.0001) and nonaerated (p = 0.01) tissue decreased. Normally aerated tissue did not change (p = 0.265). Regional compliance was higher in the intermediate (p = 0.0003) and caudal (p = 0.034) regions compared with the cranial region. Aeration did not differ between regions (p > 0.05).Conclusions and clinical relevanceAn SEL-based RPaw reduces poorly and nonaerated lung tissue in anesthetized dogs. In nonsurgical anesthetized dogs, an RPaw near 30 cmH2O is effective at improving lung aeration.  相似文献   
108.
Equine motor neuron disease (EMND) is a condition characterised by generalised weakness and muscle atrophy associated with degeneration of motor neurons in the ventral horns of the spinal cord. Despite the frequent detection of cranial nerve nuclei pathology during post mortem examination, associated clinical signs are rarely reported. This report describes a case of EMND in a pony gelding that presented with clinical signs of diffuse neuromuscular weakness associated with marked flaccidity of the tongue, making differentiation from similar neuromuscular conditions, particularly botulism, extremely challenging.  相似文献   
109.
Rapid climate change has been implicated as a cause of evolution in poorly adapted populations. However, phenotypic plasticity provides the potential for organisms to respond rapidly and effectively to environmental change. Using a 47-year population study of the great tit (Parus major) in the United Kingdom, we show that individual adjustment of behavior in response to the environment has enabled the population to track a rapidly changing environment very closely. Individuals were markedly invariant in their response to environmental variation, suggesting that the current response may be fixed in this population. Phenotypic plasticity can thus play a central role in tracking environmental change; understanding the limits of plasticity is an important goal for future research.  相似文献   
110.
The drivers which influence the types of crop protection most needed by agriculture are changing. A polarisation of approaches has resulted in the needs of organic agriculture and biotechnological agriculture, which can be identified as the current extremes of the spectrum, becoming very different. The main requirements of these two sectors are identified here and used as the basis for questioning future EU research requirements in crop protection. Factors affecting/influencing organic farming and the use of genetically modified crops are discussed in some detail.  相似文献   
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