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71.
Precision Agriculture - The spatial distribution and density of different weed species were monitored during a long-term survey over a period of 9 years on a 5.8 ha arable field...  相似文献   
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Knowledge of the extent of phenotypic variability, genetic diversity and the realized breeding progress is central for the optimum design of breeding programmes, but little information is available for triticale (× Triticosecale Wittmack). In this study, a collection of 885 diverse European triticale lines was evaluated in multilocation field trials in 2 years. We observed significant genotypic variances and high heritabilities for several agronomic and morphological traits and significant correlations among different traits including grain yield. Based on a subset of the population of 121 varieties registered in Europe between 1983 and 2014, we observed a substantial breeding progress for grain yield with a significant rate of increase of 53 kg/ha or 0.67% per year. All lines were genotyped by a genotyping‐by‐sequencing approach yielding 58 888 polymorphic markers. Our analyses revealed the absence of major population structure but a certain grouping of lines according to their origin. Taken together, our results on triticale germplasm and its breeding history provide important information for breeding programmes and future selection gain in this crop.  相似文献   
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A 3-year-old Warmblood gelding was evaluated for intermittent respiratory distress and an inspiratory noise. These signs were mainly observed at exercise but sometimes occurred at rest as well. At the age of 2 months, a severe episode of respiratory distress had necessitated a temporary tracheotomy, which had then healed uneventfully. Examination of the patient and resting endoscopy revealed no structural laryngeal alterations. Exercise endoscopy revealed episodes of active bilateral laryngeal adduction during inspiration. Spirometrically, a corresponding impairment of inspiratory airflow was identified. These abnormalities were most pronounced at the trot but they occurred at magnitudes of inspiratory airflow lower than those inducing dynamic arytenoid collapse in horses with recurrent laryngeal neuropathy. Therefore, the diagnosis of a laryngeal dyskinesia characterised by an active bilateral arytenoid adduction during inspiration was made. No specific treatment was implemented. Three years later, the owner reported that the condition was markedly improved and the horse was used for pleasure riding.  相似文献   
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ObjectiveAtrial natriuretic peptide (ANP) and cardiac troponin I (cTnI) serve as biomarkers for increased cardiac pressure/volume loading and for myocardial stress or damage. The objective was to describe the time course of plasma ANP concentrations (CpANP) and plasma cTnI concentrations (CpcTnI) in horses with mitral regurgitation (MR) compared to healthy horses at rest and after exercise, and to describe the relationship of CpANP with cardiac dimensions and intracardiac pressures.Animals15 healthy Warmblood horses and 7 Warmblood horses with MR.MethodsCardiac dimensions at rest were measured using echocardiography. All horses underwent standardized treadmill exercise. Biomarker concentrations and intracardiac pressures were measured at rest and after exercise. Hypotheses were tested using statistical methods. The level of significance was P < 0.05.ResultsHorses with MR showed increased left atrial (LA) and left ventricular (LV) dimensions but similar exercise capacity compared to healthy horses. Pulmonary capillary wedge pressures (PCWP) and CpANP increased with exercise. Horses with MR had higher PCWP and higher CpANP at rest and after exercise compared to healthy horses, with the maximum difference in CpANP reached 10 min after exercise. CpANP was significantly related to PCWP and – although inconsistently and only in healthy horses – to echocardiographic indices of LA and LV size and function. CpcTnI was low throughout the study in both groups.ConclusionsCpANP is increased in horses with MR and is related to LA pressures and to left heart dimensions. MR is not necessarily associated with exercise intolerance and exercise-induced myocardial stress or damage.  相似文献   
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European Journal of Forest Research - Research on mixed forests has mostly focused on tree growth and productivity, or resistance and resilience in changing climate conditions, but only rarely on...  相似文献   
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When you drive to somewhere far away, you will leave your current location via one of only a few important traffic junctions. Starting from this informal observation, we developed an algorithmic approach, transit node routing, that allows us to reduce quickest path queries in road networks to a small number of table lookups. For road maps of Western Europe and the United States, our best query times improved over the best previously published figures by two orders of magnitude. This is also more than one million times faster than the best known algorithm for general networks.  相似文献   
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Plasmodium falciparum chloroquine resistance is a major cause of worldwide increases in malaria mortality and morbidity. Recent laboratory and clinical studies have associated chloroquine resistance with point mutations in the gene pfcrt. However, direct proof of a causal relationship has remained elusive and most models have posited a multigenic basis of resistance. Here, we provide conclusive evidence that mutant haplotypes of the pfcrt gene product of Asian, African, or South American origin confer chloroquine resistance with characteristic verapamil reversibility and reduced chloroquine accumulation. pfcrt mutations increased susceptibility to artemisinin and quinine and minimally affected amodiaquine activity; hence, these antimalarials warrant further investigation as agents to control chloroquine-resistant falciparum malaria.  相似文献   
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