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Capsule Nestbox orientation has species-specific influences on nestbox occupation and breeding success for woodland passerines.

Aims To determine if nestbox orientation had an influence upon nestbox selection or breeding success for three co-occurring woodland passerines.

Methods We analysed 15 consecutive years of breeding data (1990–2004) from 295 nestboxes in the UK using circular statistical analyses to examine the influence of orientation upon nestbox occupation and breeding success for three species, Blue Tit Cyanistes caeruleus, Great Tit Parus major and Pied Flycatcher Ficedula hypoleuca.

Results The three species used nestboxes of all orientations during the 15-year period. The frequency of nestbox occupation by Great Tits correlated with orientation (the mean number of nests in boxes oriented south-southwest was lower than the mean number of nests in boxes facing other directions). There was no such relationship for Blue Tits or Pied Flycatchers. Nestbox orientation influenced the breeding success of Pied Flycatcher (the mean number of young to fledge from boxes oriented south-southwest was lower than from boxes facing other directions). There was no such relationship for Blue or Great Tits.

Conclusion Nestbox orientation can be an important influence on occupation and breeding success, but this differed between species. Intriguingly, although the directionality reduced nestbox occupation (Great Tit) and breeding success (Pied Flycatcher) was the same (south-southwest), there was a disparity in the influence of orientation for Great Tit (orientation influenced the frequency of occupation but not success) and Pied Flycatcher (orientation did not influence occupation but did affect success). We discuss these disparities, considering the possible influences of mating strategy, breeding phenology, nestbox microclimate and offspring quality.  相似文献   
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Objective

To document and explore the views and experiences of key stakeholders regarding the consent procedures of an emergency research clinical trial examining immediate fluid resuscitation strategies, and to discuss the implications for similar trials in future.

Methods

A social science sub-study of the FEAST (Fluid Expansion As Supportive Therapy) trial. Interviews were held with trial team members (n = 30), health workers (n = 15) and parents (n = 51) from two purposively selected hospitals in Soroti, Uganda, and Kilifi, Kenya.

Findings

Overall, deferred consent with prior assent was seen by staff and parents as having the potential to protect the interests of both patients and researchers, and to avoid delays in starting treatment. An important challenge is that the validity of verbal assent is undermined when inadequate initial information is poorly understood. This concern needs to be balanced against the possibility that full prior consent on admission potentially causes harm through introducing delays. Full prior consent also potentially imposes worries on parents that clinicians are uncertain about how to proceed and that clinicians want to absolve themselves of any responsibility for the child’s outcome (some parents’ interpretation of the need for signed consent). Voluntariness is clearly compromised for both verbal assent and full prior consent in a context of such vulnerability and stress. Further challenges in obtaining verbal assent were: what to do in the absence of the household decision-maker (often the father); and how medical staff handle parents not giving a clear agreement or refusal.

Conclusion

While the challenges identified are faced in all research in low-income settings, they are magnified for emergency trials by the urgency of decision making and treatment needs. Consent options will need to be tailored to particular studies and settings, and might best be informed by consultation with staff members and community representatives using a deliberative approach.  相似文献   
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Summary Photosensitivity in the terminal abdominal ganglion (G5) of an anomuran, the squat lobsterGalathea strigosa (Crustacea, Decapoda, Anomura), is described. In contrast to the caudal photoreceptors (CPRs) of long-tailed natantid and macruran decapod crustaceans, the caudal photosensitive elements in G5 inG. strigosa apparently lack the conventional spiking rostral conduction pathways to the thoracic ganglia, and instead make their output connections to a bilateral pair of tonic flexor motoneurones originating within the caudal ganglion itself. These flexor motoneurones modulate the activity of two bilaterally paired uropod coxopodite tonic flexor muscles. This photomodulated motoneurone (PMMN) activity is not abolished by sectioning the abdominal nerve cord anterior to G5. The pattern of photosensitivity, while differing from that shown by other CPRs, resembles instead the pattern attributed to photosensitive interneurones (PSIs) of rostral abdominal ganglia of crayfish and other long-tailed decapod crustaceans.The caudal PSIs inG. strigosa appear to be involved in the postural control of the tail-fan as it is held flexed against the cephalothorax.  相似文献   
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A rearing system for colostrum-deprived neonatal piglets   总被引:1,自引:0,他引:1  
A system for the artificial rearing of colostrum-deprived neonatal piglets is described. A total of 443 piglets in 6 batches was reared. Each piglet, immediately after birth was placed in a separate incubator which was ventilated with heated filtered air. Piglets were fed hourly by an automatic system and were offered a liquid milk substitute. The mean survival rate up to the time piglets were transferred out of the rearing unit at 2 weeks of age was 78 +/- 7%. The mean daily live weight gain up to 2 weeks of age was 148 +/- 16 g/day and the dry matter intake over the same period was 154 +/- 10 g/day per piglet.  相似文献   
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