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1.
Infanticide, the killing of conspecific young, is commonly recognized as an adaptive behavioural strategy enhancing the fitness of the perpetrator. Infanticide is supposed to be inhibited in several male rodent species after mating with a time lag to the time when perpetrators own offspring would be born. This is because males with no parental care do not recognize their own offspring. It has been suggested that copulation alone is enough to inhibit infanticidal behaviour in male rodents. Infanticidal behaviour occurs in more than 50% of male bank voles (Myodes glareolus), and offspring loss because of infanticide may have a great effect on breeding success and population recruitment. In a laboratory experiment, we studied whether infanticidal male bank voles after successful mating stop the killing of pups. Infanticidal males were paired with a female until successful copulation. After the young were born, the males’ infanticidal behaviour was studied from the time of expected birth of own pups until their post‐weaning age. We predicted that mated infanticidal males are inhibited from committing infanticide especially during the time period when pups are less than 10 d old. Against our prediction, 67% of the infanticidal males continued the killing of pups in the age of 3 d. Infanticidal behaviour remained stable, and half of the males were infanticidal still at the age of weaning of pups. Our results are contradictory to previous studies, as we observed no inhibition of infanticide during early life of pups nor increase in infanticide again when their own offspring would have reached the ‘safe’ age and size after weaning. We suggest that mating alone is not sufficient to inhibit infanticide. Thus, we suggest that other cues of the female with whom the male mated with or on her territory are needed for inhibition to occur.  相似文献   

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Assembling short fragments from known structures has been a widely used approach to construct novel protein structures. To what extent there exist structurally similar fragments in the database of known structures for short fragments of a novel protein is a question that is fundamental to this approach. This work addresses that question for seven-, nine- and 15-residue fragments. For each fragment size, two databases, a query database and a template database of fragments from high-quality protein structures in SCOP20 and SCOP90, respectively, were constructed. For each fragment in the query database, the template database was scanned to find the lowest r.m.s.d. fragment among non-homologous structures. For seven-residue fragments, there is a 99% probability that there exists such a fragment within 0.7 A r.m.s.d. for each loop fragment. For nine-residue fragments there is a 96% probability of a fragment within 1 A r.m.s.d., while for 15-residue fragments there is a 91% probability of a fragment within 2 A r.m.s.d. These results, which update previous studies, show that there exists sufficient coverage to model even a novel fold using fragments from the Protein Data Bank, as the current database of known structures has increased enormously in the last few years. We have also explored the use of a grid search method for loop homology modeling and make some observations about the use of a grid search compared with a database search for the loop modeling problem.  相似文献   

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Spatial and temporal patterns of seed bank dynamics In relation to gaps in an old growth tropical montane rainforast of Hainan Island, South China, were studied over two consecutive years. From June 2001 to June 2003, soil seed bank sampling blocks were taken near each of the four sides of each seed trap and immediately put into a nursery for observation of seedling emergence dynamics in four seasons (each experiment in each season). The abundances of seedlings that emerged from seed banks showed the trend of vine functional group (VFG) > shrub functional group (SFG) > tree functional group (TFG) > herb functional group (HFG), but the trend in species richness of seedlings that emerged from the soil seed banks was TFG > VFG > SFG > HFG. The abundances of seedlings that emerged from seed banks in the three gap zones showed no significant differences, but significant differences did exist for the species richness. The time of sampling or seasons of experiments had significant influences on both the species richness and seedling abundances. The seedling emergence processes of each experiment all revealed the unimodal patterns. Few emergences occurred 1 year after each experiment. Compared with those under closed canopies, the recruitment rates from seed to seedlings and from seedlings to saplings in gaps were higher, but the mortality rates from saplings to big trees were also higher in the gaps.  相似文献   

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Background

Little information exists on U.S. physicians who have been disciplined with licensure or restriction-of-clinical-privileges actions or have had malpractice payments because of sexual misconduct. Our objectives were to: (1) determine the number of these physicians and compare their age groups’ distribution with that of the general U.S. physician population; (2) compare the type of disciplinary actions taken against these physicians with actions taken against physicians disciplined for other offenses; (3) compare the characteristics and type of injury among victims of these physicians with those of victims in reports for physicians with other offenses in malpractice-payment reports; and (4) determine the percentages of physicians with clinical-privileges or malpractice-payment reports due to sexual misconduct who were not disciplined by medical boards.

Methods and Results

We conducted a cross-sectional analysis of physician reports submitted to the National Practitioner Data Bank (NPDB) from January 1, 2003, through September 30, 2013. A total of 1039 physicians had ≥ 1 sexual-misconduct–related reports. The majority (75.6%) had only licensure reports, and 90.1% were 40 or older. For victims in malpractice-payment reports, 87.4% were female, and “emotional injury only” was the predominant type of injury. We found a higher percentage of serious licensure actions and clinical-privileges revocations in sexual-misconduct–related reports than in reports for other offenses (89.0% vs 68.1%, P = < .001, and 29.3% vs 18.8%, P = .002, respectively). Seventy percent of the physicians with a clinical-privileges or malpractice-payment report due to sexual misconduct were not disciplined by medical boards for this problem.

Conclusions

A small number of physicians were reported to the NPDB because of sexual misconduct. It is concerning that a majority of the physicians with a clinical-privileges action or malpractice-payment report due to sexual misconduct were not disciplined by medical boards for this unethical behavior.  相似文献   

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Background  

Currently, the PDB contains approximately 29,000 protein structures comprising over 70,000 experimentally determined three-dimensional structures of over 5,000 different low molecular weight compounds. Information about these PDB ligands can be very helpful in the field of molecular modelling and prediction, particularly for the prediction of protein binding sites and function.  相似文献   

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The aim of this study is to report the experience of the Donor Tissue Bank of Victoria with bacteria isolated from musculoskeletal, skin and cardiac allografts retrieved from cadaveric donors. The results of all quality control samples for bacterial culture, taken during retrieval and processing of allografts at the DTBV for a 12 month period, were extracted and analysed. It was found that 15.7% of skin, 15.1% of heart valves and 5.8% of musculoskeletal samples had positive culture results. The number and types of organisms isolated varied with tissue type. The most commonly isolated organisms were Staphylococcus species (including S. aureus). The identity of the isolate and the number of positive specimens from the same donor were considerations in the decision concerning the suitability of tissue for subsequent implantation.  相似文献   

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Interaction between mitochondrial and nuclear genomes is expected to affect energetic phenotypes of traits linked to mitochondrial physiology, further influencing the fitness. A rodent, the bank vole (Myodes glareolus), has a population structure completely or partially introgressed with mitochondria from its relative, the red vole (M. r utilus). Females that carried either bank vole mitochondria or mitochondria from the introgressed species were repeatedly mated with males of both mtDNA types. We found that in males, but not in females, morpho-physiological phenotypes are affected by sire type, causing decreases in body mass (BM) and basal metabolic rate (BMR; including BM corrected, rBMR) in individuals sired by fathers carrying introgressed mitochondria. Higher effect sizes for the proportion of additive genetic variation (and 5.6, 1.9 and 3.6 times higher narrow sense heritability for BM, BMR and rBMR, respectively), and lower for proportion of environmental variation were detected in progeny of non-introgressed males. Our data indicate that co-adapted and possibly co-introgressed nuclear genes related to energetic physiology have an important role in adaptation to the northern conditions in bank voles, and that sex linked nuclear genes are a potential source for variation in basal metabolic rate.  相似文献   

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Gene-expression responses to an input can depend on growth conditions; in this issue, Sasson et al. (2012) show that this dependence is lower when the input results in a high degree of promoter occupancy.  相似文献   

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Hundreds of studies have assessed variation in the degree to which people experience disgust toward substances associated with pathogens, but little is known about the mechanistic sources of this variation. The current investigation uses olfactory perception and threshold methods to test whether it is apparent at the cue-detection level, at the cue-interpretation level, or both. It further tests whether relations between disgust sensitivity and olfactory perception are specific to odors associated with pathogens. Two studies (N's = 119 and 160) of individuals sampled from a Dutch university each revealed that pathogen disgust sensitivity relates to valence perceptions of odors found in pathogen sources, but not to valence perceptions of odors not associated with pathogens, nor to intensity perceptions of odors of either type. Study 2, which also assessed olfactory thresholds via a three-alternative forced-choice staircase method, did not reveal a relation between pathogen disgust sensitivity and the ability to detect an odor associated with pathogens, nor an odor not associated with pathogens. In total, results are consistent with the idea that pathogen disgust sensitivity relates to how olfactory pathogen cues are interpreted after detection, but not necessarily to the ability to detect such cues.  相似文献   

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Infanticide, the killing of conspecific young, occurs in most mammal species, like in our study species, the bank vole (Myodes glareolus). Infanticide by adult males is regarded as a strong factor affecting recruitment of young into population. It is considered as an adaptive behaviour, which may increase male fitness via resource gain or an increased access to mates. When an intruder is approaching the nest, the mother should not be present, as her nest guarding is very aggressive and successful. Pups use ultrasonic vocalisation to call their mother when mother leaves nest for foraging but it is not know which cues do infanticidal males use to find the nest with vulnerable pups to commit infanticide? We studied whether the pups' sounds or the olfactory cues of the nest guide the males of known infanticidal behavioural trait towards the nest with vulnerable pups. Four nest boxes in a large indoor arena offered different nesting cues: nest odour, pup vocalisation, both odour and sound or control with no cue. The result showed that infanticidal males were more active in their searching behaviour than non‐infanticidal males and seemed to target the nest providing only acoustic cues. Four of the males, all infanticidal, intruded the nest box. Infanticidal males seem to actively search for nests with vulnerable pups by eavesdropping pup begging calls for absent mother. However, under natural conditions, mother presence and aggressive nest protection may be an effective counter strategy against strange male infanticide. When trapping study voles from the wild, we monitored occurrence of male infanticide across the breeding season from early to late summer. Proportion of infanticidal males was between 25 and 29% of all males tested along the breeding season. Our results suggest that male infanticide seems to cause a stable threat for pup mortality in increasing breeding season density.  相似文献   

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Extrastriate cortical areas are frequently composed of subpopulations of neurons encoding specific features or stimuli, such as color, disparity, or faces, and patches of neurons encoding similar stimulus properties are typically embedded in interconnected networks, such as the attention or face-processing network. The goal of the current study was to examine the effective connectivity of subsectors of neurons in the same cortical area with highly similar neuronal response properties. We first recorded single- and multi-unit activity to identify two neuronal patches in the anterior part of the macaque intraparietal sulcus (IPS) showing the same depth structure selectivity and then employed electrical microstimulation during functional magnetic resonance imaging in these patches to determine the effective connectivity of these patches. The two IPS subsectors we identified—with the same neuronal response properties and in some cases separated by only 3 mm—were effectively connected to remarkably distinct cortical networks in both dorsal and ventral stream in three macaques. Conversely, the differences in effective connectivity could account for the known visual-to-motor gradient within the anterior IPS. These results clarify the role of the anterior IPS as a pivotal brain region where dorsal and ventral visual stream interact during object analysis. Thus, in addition to the anatomical connectivity of cortical areas and the properties of individual neurons in these areas, the effective connectivity provides novel key insights into the widespread functional networks that support behavior.  相似文献   

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