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21.
Summary The contribution of ovaries and ovarian ecdysteroids to dominance and nest initiation was tested in foundresses of Polistes gallicus at the end of hibernation. Removal of the ovaries resulted in a significant decrease of the ecdysteroid titre in haemolymph. Dominance in ovariectomized foundresses was found to be closely correlated to the size of corpora allata. The operated wasps started nest building, but they did not show any egg-laying behaviour. We conclude that both juvenile hormone and ovarian ecdysteroids contribute to degree of dominance, and that factors other than ovary development may stimulate building.  相似文献   
22.

Volume Contents

Contents of Volume 15  相似文献   
23.
24.
ABSTRACT: Pesticide runoff from dormant sprayed orchards is a major water quality problem in California's Central Valley. During the past several years, diazinon levels in the Sacramento and San Joaquin Rivers have exceeded water quality criteria for aquatic organisms. Orchard water management, via post‐application irrigation, and infiltration enhancement, through the use of a vegetative ground cover, are management practices that are believed to reduce pesticide loading to surface waters. Field experiments were conducted in Davis, California, to measure the effectiveness of these management practices in reducing the toxicity of storm water runoff. Treatments using a vegetative ground cover significantly reduced peak concentrations and cumulative pesticide mass in runoff for first flush experiments compared with bare soil treatments. Post‐application irrigation was found to be an effective means of reducing peak concentrations and cumulative mass in runoff from bare soil treatments, but showed no significant effect on vegetated treatments.  相似文献   
25.
The main purpose of The NorwegianGene Technology Act (1993) is to enforcecontainment of genetically modified organisms(GMOs) and control of GMO releases.Furthermore, the Act intends to ensure that``production and use of GMOs should take placein an ethically and socially justifiable way,in accordance with the principle of sustainabledevelopment and without detrimental effects tohealth and the environment.' Hence it isobvious that, for the Norwegian authorities,sustainable development is a normativeguideline when evaluating acceptableconsequences of GMO use and production. Inaccordance with this, we have investigated theextent to which the sustainability criteriawere decisive for the destiny of one approvedand one declined application of geneticallymodified plant release. The presentunderstanding of the ecological,socio-economical, and cultural consequences ofGMO use and release is fragmentary anduncertain. We consider the PrecautionaryPrinciple and the notion of equitabledistribution as key issues within thesustainable development framework, henceconstituting important foundations for ouranalyses. The Act is legitimizingsustainability criteria, but does not seem tosecure their conversion into concrete action.We envisage a more conscious implementation ofthe Norwegian Gene Technology Act.Sustainability concerns ecological, economical,and social values, and these can only beensured through long-term thinking, initiationof independent risk-associated research, andbroad involvement of all stakeholders in theevaluation of GMO issues and concerns.  相似文献   
26.
Systematic comparisons of the ecology between functionally similar fish species from freshwater and marine aquatic systems are surprisingly rare. Here, we discuss commonalities and differences in evolutionary history, population genetics, reproduction and life history, ecological interactions, behavioural ecology and physiological ecology of temperate and Arctic freshwater coregonids (vendace and ciscoes, Coregonus spp.) and marine clupeids (herring, Clupea harengus, and sprat, Sprattus sprattus). We further elucidate potential effects of climate warming on these groups of fish based on the ecological features of coregonids and clupeids documented in the previous parts of the review. These freshwater and marine fishes share a surprisingly high number of similarities. Both groups are relatively short-lived, pelagic planktivorous fishes. The genetic differentiation of local populations is weak and seems to be in part correlated to an astonishing variability of spawning times. The discrete thermal window of each species influences habitat use, diel vertical migrations and supposedly also life history variations. Complex life cycles and preference for cool or cold water make all species vulnerable to the effects of global warming. It is suggested that future research on the functional interdependence between spawning time, life history characteristics, thermal windows and genetic differentiation may profit from a systematic comparison of the patterns found in either coregonids or clupeids.  相似文献   
27.
The commercial introduction of genetically modified organisms (GMOs) has revealed a broad range of views among scientists and other stakeholders on perspectives of genetic engineering (GE) and if and how GMOs should be regulated. Within this controversy, the precautionary principle has become a contentious issue with high support from skeptical groups but resisted by GMO advocates. How to handle lack of scientific understanding and scientific disagreement are core issues within these debates. This article examines some of the key issues affecting precaution as a legal standard and as an approach to the use of science in decision-making processes. It is pointed out that there is a need for reflection over the level of scientific evidence required for applying the precautionary principle as well as who should have the burden of proof when there are uncertainties. Further, an awareness of the broader scientific uncertainties found in GMO risk assessment implies that a precautionary approach must be elaborated: both for acknowledging uncertainties and for identification of scientific responses. Since precaution is an important issue within the sustainable development framework, it is suggested that sustainability can provide a normative standard that can help to reveal the influence and negotiate the importance of the various forms of uncertainty. Wise management of uncertainties and inclusion of normative aspects in risk assessment and management may help to ensure sustainable and socially robust GMO innovations at present and in the future.  相似文献   
28.

Objectives

To determine the proportion of children that require surgery in the first year of life and thereafter in order to improve the counseling of parents with a fetus with a right aortic arch (RAA).

Methods

Fetuses diagnosed with isolated RAA, defined as the absence of intra- or extracardiac anomalies, between 2007 and 2021 were extracted from the prospective registry PRECOR.

Results

In total, 110 fetuses were included, 92 with a prenatal diagnosis of RAA and 18 with double aortic arch (DAA). The prevalence of 22q11 deletion syndrome was 5.5%. Six pregnancies were terminated and five cases were false-positive; therefore, the follow-up consisted of 99 neonates. Surgery was performed in 10 infants (10%) in the first year of life. In total, 25 (25%) children had surgery at a mean age of 17 months. Eight of these 25 (32%) had a DAA. Only one child, with a DAA, required surgery in the first week of life due to obstructive stridor.

Conclusions

Children with a prenatally diagnosed RAA are at a low risk of acute respiratory postnatal problems. Delivery in a hospital with neonatal intensive care and pediatric cardiothoracic facilities seems only indicated in cases with suspected DAA. Expectant parents should be informed that presently 25% of the children need elective surgery and only incidentally due to acute respiratory distress.  相似文献   
29.

Objective

We aimed to assess current prenatal detection rate (DR) of aortic coarctation (CoA) and its impact on neonatal outcome in the Netherlands to evaluate the efficacy of the Dutch screening protocol in which the cardiac four-chamber view, outflow tracts and three-vessel view are compulsory.

Methods

All prenatally and postnatally diagnosed CoA cases between 2012 and 2021 were extracted from our PRECOR-registry. Annual DRs were calculated with a focus on the trend over time and attributing factors for detection. Postnatal outcome was compared between prenatally detected and undetected cases.

Results

49/116 cases (42.2%) were detected prenatally. A higher chance of detection was found for cases with extracardiac malformations (71.4%; p = 0.001) and the more severe cases with an aortic arch hypoplasia and/or ventricular septal defect (63.2%; p = 0.001). Time-trend analysis showed no improvement in DR over time (p = 0.33). Undetected cases presented with acute circulatory shock in 20.9% and were more likely to have severe lactic acidosis (p = 0.02) and impaired cardiac function (p < 0.001) before surgery.

Conclusion

Even in a well-organized screening program, the DR of CoA still requires improvement, especially in isolated cases. The increased risk of severe lactic acidosis in undetected cases stresses the need for urgent additions to the current screening program, such as implementation of the three-vessel trachea view and measurement of outflow tracts.  相似文献   
30.
On October 12, 2012, the provincial public health directorate of Salzburg reported a suspected norovirus (NV) outbreak among guests of a wedding–reception. The investigation aimed to confirm the causative agent, to identify the mode of transmission and to implement appropriate preventive measures. A probable outbreak case was defined as a wedding guest with diarrhoea or vomiting with disease onset from 7 to 10 October 2012 and who consumed food at the wedding dinner prepared by a hotel in the province Salzburg on 6 October 2012. A confirmed outbreak case fulfilled the criteria of a probable outbreak case and had a laboratory-confirmed NV infection. We conducted a cohort-investigation among the wedding guests. The case definitions were fulfilled in 26 wedding guests (25 %) including 2 confirmed cases. Females were 3.2 times more likely to develop disease (95 % CI 1.4–7.2) as compared to males. A mushroom dish was found to be associated with disease risk among females (risk ratio 2.3, 95 % CI 1.2–4.3). Two of 2 tested case-patients and 6 of 14 kitchen workers tested were positive for NV GII.4 Sydney. One kitchen staff-member worked during the wedding dinner despite diarrhoea. No food safety training was documented for the employees and the kitchen staff’s restroom was lacking operational facilities for hand hygiene. We report the first investigated outbreak due to GII.4 Sydney, which was likely due to a symptomatic kitchen worker. Gender-specific eating behaviour may have posed female guests at higher risk of NV infection.  相似文献   
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