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181.
Introduction

In the care of heart failure patients, telemonitoring is receiving growing attention. The main purpose of this study was to determine the effect of continuous telemonitoring with an implantable loop recorder (ILR, Reveal XT), a novel strategy in the management of stable heart failure patients without a cardiac implantable device. Furthermore, little is known about the incidence of subclinical arrhythmias in this specific group of patients.

Materials and Methods

Stable heart failure patients, New York Heart Association Class II and III, without recent hospitalisation or upcoming intervention, were included. After implantation of the ILR there was regular contact with the research nurse on a pre-specified basis. Clinic visits and telephonic interviews were alternated for a minimum of 1 year. Parallel visits to their treating physician continued according to standard care. The treating physician was blinded for the ILR findings, accept for pre-specified, significant arrhythmic events.

Results

Thirty patients were included and followed for a median duration of 12 months. In 13 patients, data from the loop recorder led to therapeutic changes. One patient received a pacemaker. Eight patients developed atrial fibrillation, all subclinical, with a mean burden of 65.8 ± 173.2 min/day.

Conclusion

The use of an ILR could potentially impact patient management. Additional study is needed in different patient populations (e. g. higher risk groups) to assess if an ILR could also impact on endpoints such as heart failure hospitalisation.

  相似文献   
182.
Most bird species produce different acoustic signals in different behavioural contexts. This intraspecific variation in signal types is thought to be the result of selection for optimal communication in each context. Doves in the genus Streptopelia have three distinct behavioural contexts in which they produce coo vocalizations. Some Streptopelia species have three acoustically similar coo vocalizations associated with the three contexts, but in others the coo vocalizations differ in acoustic structure. Using a well-resolved phylogeny, we examined whether acoustic differentiation between coo types was the ancestral state. Unexpectedly, the results showed that the common ancestor of Streptopelia had differentiated coos rather than a single coo type. This result implies that context-specific acoustic signals disappeared from the vocal repertoire independently at least two times. We further tested whether different context-dependent signal types follow different evolutionary pathways and whether they differ in rate of evolutionary change. We found that the long-range signal (perch-coo) evolves at a higher rate than the short-range signal (bow-coo). These results are discussed in relation to selection for species recognition and transmission requirements.  相似文献   
183.
Scholte, P., de Kort, S. & van Weerd, M. 2000. Floodplain rehabilitation in Far North Cameroon: expected impact on bird life. Ostrich 7 (1): 112–117.

The Logone floodplain in the sahelo-Sudanian zone of Cameroon used to be a highly productive ecosystem. Perennial pastures and fish played a crucial role for fishermen, pastoralists and wildlife. The construction of an upstream dam reduced inundation causing widespread degradation Nonetheless, approximately 350 bird species have still been observed. They include eleven waterfowl species which surpass the IWRB/Ramsar criterion one % of West African population). The few available surveys suggest that prior to the dam construction, the area harbored an even more abundant birdlife. Presently possibilities exist to release excess water for floodplain rehabilitation. In 1994, a pilot release has been executed to verify predicted advantages for men and wildlife. Larger scale rehabilitation of the Logone floodplain is formulated, based on the pilot release results. Annual total waterfowl, as well as heron colony counts have been executed showing an increase in bird numbers. Data variability questions somewhat the conclusion that this has been exclusively due to increased flooding. Additionally, bird populations of degraded annual grasslands and well flooded perennial grasslands have been assessed by line transacts. Results showed the much higher numbers of waterfowl and passerines in perennial grassland. Hydrological and vegetation monitoring showed a change of annual into perennial grassland due to the re-flooding, which might lead to increased bird populations. Questions remain how to extrapolate these findings to the entire area to be re-flooded, justifying continuous counting and studying factors limiting bird populations. Such a study started for the Black Crowned Crane, a resident flagship species. For migratory species, surveys are recommended to assess the role of other wetlands in the Lake Chad basin.  相似文献   
184.
The study followed the harvest of natural willow from three wetlands using a prototype modified agricultural round baler nicknamed a Bio-Baler. The study reports fuel characteristics and combustion testing of biomass harvested from natural willow rings. Composition of native willow species in the harvested willow rings was determined. We specifically measured regrowth of the biomass and number of regenerated stems per stump 1 year after harvest to determine how different willow species responded to mechanical biomass cutting with the Bio-Baler. The results of combustion testing for the natural willow were essentially similar to those with “conventional” wood chips or planted willows. The ash content was approximately 1.65%, slightly lower than for planted willow plantations. The calorific value of the natural willow was 19.6 MJ kg?1 (dry basis) similar to what is expected for wood and planted willow. Four Salix species (Salix bebbiana Sarg., Salix petiolaris Sm., Salix eriocephala Michx., and Salix discolor Muhl) were identified in the willow rings. Stem biomass increased for all species except S. bebbiana after willow was harvested with the Bio-Baler. Overall, willow regeneration was not affected by mechanical harvesting compared to hand cutting. Regenerated stem density was 93 stems per square meter for mechanically harvested stumps compared to 105 stems per square meter for hand-pruned stumps. Based on the results, biomass harvested from natural willow rings has acceptable fuel characteristics when compared to purpose-grown willows and mechanical harvest with a Bio-Baler does not have a negative effect on willow regeneration.  相似文献   
185.
Thermodynamic and kinetic parameters are of prime importance for designing crystallization processes. In this article, Preferential Crystallization, as a special approach to carry out enantioselective crystallization, is described to resolve the enantiomers of the chiral fungicide fenamidone. In preliminary investigations the melting behavior and solid–liquid equilibria in the presence of solvents were quantified. The analyses revealed a stable solid phase behavior of fenamidone in the applied solvents. Based on the results obtained, a two–step crystallization route was designed and realized capable of providing highly pure enantiomers. An initial Preferential Crystallization of the racemate was performed prior to crystallizing the target enantiomer preferentially out of the enriched mother liquor. Chirality 28:514–520, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
186.
Plasma levels of the eicosanoids PGE2, 6k-PGF1 alpha and TXB2 as well as platelet aggregation were determined in 12 healthy subjects, aging 23-50. It was our assumption that the parameters could be of use to monitor cancer patients, provided that the results of the determinations could be well reproduced and that the variation within a healthy population was small. In a group of laboratory employees (6 males and 6 females) blood samples were taken, 3 times, with a 2 week interval, under controlled conditions. Drug ingestion was recorded, and taken into account for the evaluation. The ranges of plasma eicosanoid, and of in vitro platelet aggregation values were large. The variation in both parameters was in large part due to intra-individual variation (based on the different values obtained in one subject). In part however, the variation could be traced to ingestion of non steroidal anti inflammatory drugs (NSAIDs). The following abbreviations were used: NSAID = non steroidal anti inflammatory drug, PGE2 = prostaglandin E2, 6k-PGF1 alpha = 6-ketoprostaglandin-F1 alpha, TXB2 = thromboxane B2, TXA2 = thromboxane A2, PGI2 = prostaglandin I2 = prostacyclin, RIA = radio immuno assay, ADP = adenosine diphosphate.  相似文献   
187.
188.
Ancient mariners knew that dust whipped up from deserts by strong winds travelled long distances, including over oceans. Satellite remote sensing revealed major dust sources across the Sahara. Indeed, the Bodélé Depression in the Republic of Chad has been called the dustiest place on earth. We analysed desert sand from various locations in Chad and dust that had blown to the Cape Verde Islands. High throughput sequencing techniques combined with classical microbiological methods showed that the samples contained a large variety of microbes well adapted to the harsh desert conditions. The most abundant bacterial groupings in four different phyla included: (a) Firmicutes—Bacillaceae, (b) Actinobacteria—Geodermatophilaceae, Nocardiodaceae and Solirubrobacteraceae, (c) Proteobacteria—Oxalobacteraceae, Rhizobiales and Sphingomonadaceae, and (d) Bacteroidetes—Cytophagaceae. Ascomycota was the overwhelmingly dominant fungal group followed by Basidiomycota and traces of Chytridiomycota, Microsporidia and Glomeromycota. Two freshwater algae (Trebouxiophyceae) were isolated. Most predominant taxa are widely distributed land inhabitants that are common in soil and on the surfaces of plants. Examples include Bradyrhizobium spp. that nodulate and fix nitrogen in Acacia species, the predominant trees of the Sahara as well as Herbaspirillum (Oxalobacteraceae), a group of chemoorganotrophic free-living soil inhabitants that fix nitrogen in association with Gramineae roots. Few pathogenic strains were found, suggesting that African dust is not a large threat to public health.  相似文献   
189.
Lipophorin, the protein that specifically binds juvenile hormone in the hemolymph of the Colorado potato beetle, Leptinotarsa decemlineata, is a high-density lipoprotein of Mr ~ 574,000. Lipophorin contains 43% lipid and is composed of two apoproteins: apolipophorin I (Mr ~ 251,000) and apolipophorin II (Mr ~ 78,000). Both apoproteins contain mannose residues. Carotenoids make up a substantial part of the lipid fraction. Lipophorin constitutes about 25% of the total hemolymph proteins. Its concentration in the hemolymph (26 μM in 4-day-old long-day and 40 μM in 4-day-old short-day beetles) changes with different physiological conditions concomitant with changes in total protein content. Lipophorin specifically binds 10R-juvenile hormone III with high affinity. The dissociation constant for 10R-juvenile hormone III is 12 ± 2 nM. One lipophorin molecule contains one specific juvenile hormone-binding site. The concentration of binding sites therefore equals that of lipophorin in hemolymph.  相似文献   
190.
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