Distribution of microbiological indicators of fecal pollution in the riverine substrates

Distribution of fecal microorganisms in water, periphyton, and sediment was studied along the ?rnovnica river (Croatia) over a 1.5-year period. It was found that periphyton was inhabited by the highest number of investigated bacteria, while lower numbers of them were found in sediment and the lowest in surface water of the river. The concentrations of fecal microorganisms in periphyton and partly in sediment were found to be significantly higher in the middle of the river course, near the town of ?rnovnica, while according to the analysis of surface water the highest degree of pollution was reached on its estuary. The results were explained with respect to bacterial?Calgal associations. Considering the fact that most of the river microorganisms are associated with periphyton and sediment particles and only a small number of them is in the free-living form, microbiological analysis of both periphyton and sediment together with water samples has been suggested when fecal pollution of a river is concerned.     

Digit ratios have poor indicator value in a wild bird population

Early androgen exposure is known to have long-lasting effects on phenotype, behaviour and even fitness, but difficulties in measuring the exposure hinders the study of its importance in evolutionary context. Digit ratios have been highlighted as a potential easy-to-measure indicator of early steroid exposure, as they have been suggested to reflect steroid, mainly testosterone levels during prenatal development. However, evidence for digit ratios reflecting early steroid levels is weak, as experimental studies, especially in wild populations, are scarce. We studied the association between maternally derived yolk androgens and digit ratios (2D:4D, 2D:3D and 3D:4D) using both correlative data and a rather high level of experimental elevation of yolk androgens in a passerine bird, the pied flycatcher (Ficedula hypoleuca). We also examined whether digit ratios have indicator value in an evolutionary context by studying correlations between digit ratios and reproductive traits, secondary sexual traits and exploratory behaviour. We did not find any association between digit ratios and yolk androgen level either in correlative or experimental data. Digit ratios were neither related to any of the reproductive and secondary sexual traits or exploratory behaviour measured. There was, however, a sex difference in 2D:3D and 3D:4D of adult birds (due to second and fourth digits being shorter in females), which was not apparent in fledglings or captivity-raised juveniles. This suggests that either the sex difference may develop as late as during the sexual maturation for breeding. These results indicate that, in this species, digit ratios are not reliable markers of maternally derived yolk androgen exposure and that they bear little relevance as correlates of the adaptive traits we measured.     

Prospecting at conspecific nests and exploration in a novel environment are associated with reproductive success in the jackdaw

Consistent behavioural differences between individuals of the same population (“personality” variation) might arise if individuals follow different life-history strategies. Thus, it would be important to determine how personality variation relates to behaviours potentially associated with life-history strategies, such as those related to the use of information about the state of the environment. Little is, however, known about how personality is associated with information use and reproductive success. We tested whether wild social jackdaws, Corvus monedula, show consistent behavioural differences in their exploratory behaviour (in a novel environment in the lab and in their reaction towards a novel object in the wild) and prospecting behaviour (number of visits to conspecific nests). We furthermore examined whether these behavioural traits are linked with each other and predictors of reproductive success. Breeding jackdaws were consistent in their exploratory behaviour within, and in their prospecting behaviour between, years. Exploratory behaviour in the novel environment was correlated with the latency to approach a novel object in the wild but not with the frequency of prospecting at conspecific nests. Highly exploratory males and females and frequently prospecting males produced fewer fledglings than less exploratory individuals or less prospecting males, respectively. We discuss the importance of consistent individual differences in exploration and information sampling on individual fitness.     

Temporal peaks in social information: prospectors investigate conspecific nests after a simulated predator visit

Individuals of many taxa gather social information in order to make informed decisions with lowered unpredictability. Social information may show temporal periods of higher information value during certain events. However, the value of information is expected to decrease with time since the event and individuals accessing this information are expected to do so quickly. In birds, prospectors visit the nests of other individuals to gather information about reproductive decisions and breeding success. Individuals are known to prospect even during their own breeding to access this information. We investigated prospecting behavior of pied flycatchers (Ficedula hypoleuca) at conspecific nests within a short time period following a simulated predator visit. We performed predator and control presentations at flycatcher nests, and recorded all prospectors (foreign conspecific individuals) visiting these nests within 45-min periods before and after the presentations. We found a significant increase in conspecific prospectors visiting focal nests after the presentation of a predator near the nest. The prospectors in our data comprised mainly pied flycatchers actively breeding in the neighborhood of the focal nest. We also found that the increase in prospecting at these nests is of short-duration, and that prospecting rates decreased back to background prospecting levels relatively quickly. Our results find support for the prediction that individuals may respond to temporally peaking value of information after certain observable events. This result suggests that prospecting may be especially aimed at specific periods of high information value.     

Strategically designed sample composition for fastest screening of polychlorinated biphenyl congeners in water samples

A new strategy for preparing composite samples of special interest and applicability in environmental screening studies is presented. The use of supersaturated experimental design matrices to conduct the sample composition of water sample specimens in screening studies is demonstrated. In contrast to well known conventional sample composition, this strategic approach provides analytical objects allowing the accurate prediction of analyte concentration levels in the original individual sample specimens while fixing the number of experiments to be carried out down to the very number of sample specimens. This will be of special importance when dealing with analytes that require complicated, labour intensive and expensive analytical processes. To reach this goal, two main conditions must be fulfilled. The first one is the sparsity effect (Pareto principle) which holds for the specimens in the sampling campaign. This means that the number of really anomalous or contaminated specimens, as compared to the total number of specimens to be analysed, is low. In environmental screening studies, frequently this situation can be reasonably assumed. The second condition is to have an effective manner to develop and solve the experimental designs required to build-up the composite samples. The challenging problem of screening PCBs in water samples has been tackled to show the usefulness of this strategic approach by combining chemometrically assisted sample composition and rapid analysis using solid-phase microextraction of the composite samples.     

Prenatal sonographic detection of intra-abdominal extralobar pulmonary sequestration: Report of three cases and literature review

Three cases of intra-abdominal extralobar pulmonary sequestration detected antenatally by ultrasound are reported. One case was associated with a large left diaphragmatic hernia. Sonographically, all the cases were found in the left supra-renal region presenting as a well-defined echogenic mass with cystic hypoechoic areas. The condition should be considered in the differential diagnosis of all antenatally detected upper abdominal echogenic masses, particularly when associated with a diaphragmatic hernia. Postnatal ultrasound-guided fine needle aspiration biopsy in one case yielded respiratory type epithelium and this procedure could provide a reasonably confident diagnosis of the lesion.     

Bonding and supportive relationships among black professional women: Rituals of restoration

In two-day assessment workshops 71 black professional women explored the kinds of supportive relationships they have formed with significant black women friends and the consequences of these supportive relationships for their growth and development. Findings show two major types of supportive relationships: (1) other-oriented relationships, in which participants' bonds with other black women emphasize the provision of support to the other, and (2) self-enhancing relationships, in which participants' bonds with other black women are reciprocal in nature or are oriented toward self. Within these two types of relationships, three main functions of support were found: (1) social companionship, (2) task help, and (3) supportiveness. Of these three functions, the receipt of supportiveness consisting of emotional support, high commitment to one another, and encouragement to tackle life's obstacles resulted in the highest levels of growth and development among the participants, thus most effectively validating and addressing their experience of bicultural stress.     

Kin discrimination in the spotted hyena (<Emphasis Type="Italic">Crocuta crocuta</Emphasis>): nepotism among siblings

We examined patterns of affiliation, association, and aggression to inquire whether spotted hyenas (Crocuta crocuta) can distinguish among various groups of maternal and paternal siblings. If so, and if these animals conform to predictions of kin selection theory, then behavioral interactions among hyenas should vary with relatedness. We also considered familiarity-based recognition and phenotype matching as mechanisms hyenas might use to recognize kin. Patterns of affiliative behavior indicated that hyenas favored full-sibling littermates over half-sibling littermates or any other group of half-siblings. Rates of dyadic aggression generally did not vary with kinship. Hyenas associated more closely with half-sibling littermates than with non-littermate half-siblings, and hyenas affiliated more with maternal half-siblings than with paternal half-siblings, suggesting that familiarity-based cues might mediate discrimination among these sibling classes. In addition, operation of a phenotype-matching mechanism was suggested by the preference hyenas demonstrated during affiliative interactions for full- over half-sibling littermates, and by their lack of preference in these interactions for half-sibling littermates over non-littermate half-siblings. Phenotype matching was also suggested by our observation that paternal half-siblings cooperated more, and fought less, than did non-kin. Our data indicate that hyenas can discriminate among various types of siblings, that their social behavior conforms to predictions of kin selection theory, and that they recognize kin using mechanisms of both familiarity and phenotype matching.Communicated by S. Alberts