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831.
Craig A. Walling Nick J. Royle Jan Lindström Neil B. Metcalfe 《Behavioral ecology and sociobiology》2010,64(4):541-548
Sexual selection acting on male traits through female mate choice is commonly inferred from female association preferences
in dichotomous mate choice experiments. However, there are surprisingly few empirical demonstrations that such association
preferences predict the likelihood of females reproducing with a particular male. This information is essential to confirm
association preferences as good predictors of mate choice. We used green swordtails (Xiphophorus helleri) to test whether association preferences predict the likelihood of a female reproducing with a male. Females were tested
for a preference for long- or short-sworded males in a standard dichotomous choice experiment and then allowed free access
to either their preferred or non-preferred male. If females subsequently failed to produce fry, they were provided a second
unfamiliar male with similar sword length to the first male. Females were more likely to reproduce with preferred than non-preferred
males, but for those that reproduced, neither the status (preferred/non-preferred) nor the sword length (long/short) of the
male had an effect on brood size or relative investment in growth by the female. There was no overall preference based on
sword length in this study, but male sword length did affect likelihood of reproduction, with females more likely to reproduce
with long- than short-sworded males (independent of preference for such males in earlier choice tests). These results suggest
that female association preferences are good indicators of female mate choice but that ornament characteristics of the male
are also important. 相似文献
832.
The detrimental effects of a ringing phone on cognitive performance were investigated in four experiments. In Experiments 1 and 2, the effects of different types of sounds (a standard cell phone ring, irrelevant tones and an instrumental song commonly encountered by participants) on performance were examined. In Experiment 1, slower responses were observed in all auditory groups relative to a silence condition, but participants in the ring and song conditions recovered more slowly. In Experiment 2, participants who were warned about the potential for distraction recovered more quickly, suggesting a benefit of this prior knowledge. This investigation continued in a college classroom setting (Experiments 3a and 3b); students were exposed to a ringing cell phone during the lecture. Performance on a surprise quiz revealed low accuracy rates on material presented while the phone was ringing. These findings offer insight into top-down cognitive processes that moderate involuntary orienting responses associated with a common stimulus encountered in the environment. 相似文献
833.
This paper describes a case study of decision making in a steelworks maintenance department, which led to the introduction of a major initiative to improve safety performance. The origin of the decision process lay, however, not with safety, but with an earlier decision to consider outsourcing the maintenance department. When it was decided that this was not feasible a new General Manager was appointed to turn around the performance of the now demoralised department. In his search for solutions and the external developments taking place in parallel he found an initiative which seemed to link his main concerns with a parallel concern for safety improvement. The philosophy behind it and the vision and strategy which was developed to carry it led to a much more participative approach, driven by clearly defined key performance indicators. Safety was chosen as the lead objective. This paper describes the development of the decision process and briefly explains its results. 相似文献
834.
Leonardo Gucciardo Anne Uyttebroek Ivo De Wever Marleen Renard Filip Claus Roland Devlieger Liesbeth Lewi Luc De Catte Jan Deprest 《黑龙江环境通报》2011,31(7):678-688
Sacrococcygeal teratoma (SCT) is one of the most common tumors in newborns with a birth prevalence of up to 1 in 21 700 births. Routine fetal anomaly screening programs allow for prenatal diagnosis in many cases. Fetal ultrasound with Doppler evaluation and more recently magnetic resonance imaging may be used to document the extent of the tumor as well as identifying the population at risk for serious fetal complications. Rapidly growing SCT and highly vascularized tumors are more likely to have hemodynamic repercussions. Fetal hydrops is usually considered as a poor prognostic marker and a potential indicator for fetal intervention. Newborns with SCT require stabilization prior to early surgical resection. In case of malignancy additional chemotherapy may be required. SCT may result in significant morbidity, either directly or as a consequence of surgical therapy. Careful postnatal follow-up is required for timely identification and treatment of complications as well as recurrence. This paper aims to review the perinatal management of this condition. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
835.
836.
Glamann Josefine Hanspach Jan Abson David J. Collier Neil Fischer Joern 《Regional Environmental Change》2017,17(5):1303-1313
Regional Environmental Change - Food security and biodiversity conservation are key challenges of the twenty-first century. While traditionally these two challenges were addressed separately,... 相似文献
837.
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839.
Karel Allegaert Anouk E. Muller Francesca Russo Sam Schoenmakers Jan Deprest Birgit C.P. Koch 《黑龙江环境通报》2020,40(9):1178-1184
Antimicrobial prophylaxis during surgery aims to prevent post-operative site infections. For fetal surgery, this includes the fetal and amniotic compartments. Both are deep compartments as drug equilibrium with maternal blood is achieved relatively late. Despite prophylaxis, chorio-amnionitis or endometritis following ex utero intrapartum treatment or fetoscopy occur in 4.13% and 1.45% respectively of the interventions. This review summarizes the observations on two commonly administered antimicrobials (cefazolin, clindamycin) for surgical prophylaxis during pregnancy, with emphasis on the deep compartments. For both compounds, antimicrobial exposure is on target when we consider the maternal and fetal plasma compartment. In contrast, amniotic fluid concentrations-time profiles display a delayed and much more blunted pattern, behaving as deep compartment. For cefazolin, there are data that document further dilution in the setting of polyhydramnios. Along this deep compartment concept, there is some accumulation during repeated administration, modeled for cefazolin and observed for clindamycin. The relative underexposure to antimicrobials in amniotic fluid may be reflected in the pattern of maternal-fetal complications after fetal surgery, and suggest that antimicrobial prophylaxis practices for fetal surgery should be reconsidered. Further studies should be designed by a multidisciplinary team (fetal surgeons, clinical pharmacologists and microbiologists) to facilitate efficient evaluation of antimicrobial prophylaxis. 相似文献
840.