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801.
This is the first report of gynandromorphy in Isoptera. An Asian dry-wood termite, Neotermes koshunensis (Shiraki) [Kalotermitidae], possessing both male and female phenotypic characteristics, was found on Okinawa Island, Japan. This deformed individual showed morphological and anatomical hermaphroditism in the abdomen. The right side of the seventh sternite was the female form and contained an ovary, while the left side was the male form and contained a testis. Genotypic analysis revealed that this individual was a genotypic bilateral chimera. These results suggested that the termite was a bilateral gynandromorph with a male left side and a female right side. As reported previously in other insects, double fertilization (by two sperms, one with an X and one with a Y chromosome) of a binucleate egg is the most likely mechanism that generated this genotypic bilateral chimera. N. koshunensis has the ability to reproduce through parthenogenesis, in which the secondary polar body is likely to be used for nuclear phase recovery. If the second polar body in this mechanism has high fertility and healthy embryogenic potential, like an egg nucleus, some of gynandromorphs might be produced by a side effect of parthenogenetic ability.  相似文献   
802.
To explore the role of the volatiles emitted from male labial gland (LG) of the bumblebee Bombus ardens ardens, we investigated the responses of virgin queens and males to volatiles using a gas chromatography–electroantennographic detector (GC–EAD) system and Y-tube olfactometer. GC–EAD analysis revealed that citronellol, the main compound detected in the male LG, caused clear electrophysiological responses in the antennae of B. a. ardens virgin queens and males although two minor compounds elicited antennal responses when applied in a high concentration. Behavioral tests using a Y-tube olfactometer showed that queens and males were significantly attracted to both LG extracts and citronellol more than to the solvent alone. This is the first study to demonstrate that citronellol as a major compound of male scent-marking pheromone in B. a. ardens functions as a sex attractant for queens. The results also suggest that this compound has another function as a trail marker used by males.  相似文献   
803.
After extensive flooding in 2002, the European Union Solidarity Fund (EUSF) was created as an ex post loss-financing vehicle for EU member states and candidate countries in the case of disasters that exceed the government’s resources to cope. The EUSF is viewed as a valuable instrument for pooling risk among countries in Europe and potentially as a model for financing loss and damage from climate change in vulnerable countries worldwide. This paper assesses its future prospects taking account of reforms adopted in 2014. Our analysis is based on three recognized aims of the Solidarity Fund: its promotion of solidarity with those countries having the least capacity to cope with major disasters; its contribution to proactive disaster risk reduction and management (climate adaptation); and its robustness with regard to its risk of depletion (stress testing). Using a simulation approach for future disasters, we conclude that the reformed EUSF’s risk of depletion, although it is reasonably robust to more frequent disasters, could be reduced by increasing member state contributions and/or engaging in risk transfer. The European Commission has taken important steps in linking the fund to proactive risk reduction; yet, by changing its budgeting practices, the commission could be more proactive in encouraging risk management in member states. In its current form, the EUSF does not embed needs-based solidarity. Lower-income “new” member states have received disproportionately less compensation in terms of eligible losses, although on average, they have received more disaster aid than what they contribute to the fund. Solidarity could be enhanced by changing the rules for disbursing aid. After briefly describing alternative risk-pooling models in the Caribbean, Africa, and Europe, we suggest how design features of the EUSF as compared to other regional risk pools can inform discussions on the Warsaw International Loss and Damage Mechanism.  相似文献   
804.
We present a methodology for using a domestic water use time series that were obtained from Yellow River Conservancy Commission, together with the climatic records from the National Climate Center of China to evaluate the effects of climate variability on water use in the Yellow River Basin. A suit of seven Global Circulation Models (GCMs) were adopted to anticipate future climate patterns in the Yellow River. The historical records showed evidences of rises in temperature and subsequent rises in domestic water demand in the basin. For Upstream of Longyangxia region, the impact was the least, with only 0.0021?×?108 m3 for a temperature increase of 1 °C; while for Longyangxia-Lanzhou region, domestic water use was found to increase to 0.18?×?108 m3 when temperature increases 1 °C. Downstream of Huayuankou was the region with the most changes in temperature that gave the highest increase of 1.95?×?108 m3 in domestic water demand for 1 °C of change of temperature. Downstream of Huayuankou was identified as the most vulnerable area, where domestic water demand increases nearly by 42.2 % with 1 °C increase of temperature. Judging from the trends of temperature range, we concluded that future temperature in Yellow River Basin has an increasing tendency. This could worsen the existing issues of domestic water demand and even more to trigger high competition among different water-using sectors.  相似文献   
805.
806.
Norovirus (NoV) is recognized as the most common cause of foodborne outbreaks. In 2014, an outbreak of acute gastroenteritis occurred on a cruise ship in Brazil, and NoV became the suspected etiology. Here we present the molecular identification of the NoV strains and the use of sequence analysis to determine modes of virus transmission. Food (cream cheese, tuna salad, grilled fish, orange mousse, and vegetables soup) and clinical samples were analyzed by ELISA, conventional RT-PCR, qRT-PCR, and sequencing. Genogroup GII NoV was identified by ELISA and conventional RT-PCR in fecal samples from 5 of 12 patients tested (41.7%), and in the orange mousse food sample by conventional RT-PCR and qRT-PCR. Two fecal GII NoV samples and the orange mousse GII NoV sample were successfully genotyped as GII.Pe (ORF 1), revealed 98.0–98.8% identities among them, and shared phylogenetically distinct cluster. Establishing the source of a NoV outbreak can be a challenging task. In this report, the molecular analysis of the partial RdRp NoV gene provided a powerful tool for genotyping (GII.Pe) and tracking of outbreak-related samples. In addition, the same fast and simple extraction methods applied to clinical samples could be successfully used for complex food matrices, and have the potential to be introduced in routine laboratories for screening foods for presence of NoV.  相似文献   
807.
The importance of olfaction in birds’ social behavior has long been denied. Avian chemical signaling has thus been relatively unexplored. The black-legged kittiwake provides a particularly appropriate model for investigating this topic. Kittiwakes preferentially mate with genetically dissimilar individuals, but the cues used to assess genetic characteristics remain unknown. As in other vertebrates, their body odors may carry individual and sexual signatures thus potentially reliably signaling individual genetic makeup. Here, we test whether body odors in preen gland secretion and preen down feathers in kittiwakes may provide a sex and an individual signature. Using gas chromatography and mass spectrometry, we found that male and female odors differ quantitatively, suggesting that scent may be one of the multiple cues used by birds to discriminate between sexes. We further detected an individual signature in the volatile and nonvolatile fractions of preen secretion and preen down feathers. These results suggest that kittiwake body odor may function as a signal associated with mate recognition. It further suggests that preen odor might broadcast the genetic makeup of individuals, and could be used in mate choice to assess the genetic compatibility of potential mates.  相似文献   
808.
Large technical systems serving the everyday needs of people, such as water supply systems, power grids or communication networks, are rich in accumulated metals. Over time, parts of these systems have been taken out of use without the system infrastructure being removed from its original location. Such metal stocks in hibernation thus constitute potential resource reservoirs accessible for recovery. In this paper, obsolete stocks of copper situated in the local power grids of two Swedish cities are quantified. Emphasis is also on economic conditions for extracting such “hibernating” cables. The results show that on a per customer basis, the two power grids contain similar amounts of copper, i.e. 0.04–0.05 tonnes per subscriber. However, the share of the copper stock that is in hibernation differs between the grids. In the larger grid of Gothenburg, almost 20% of the copper accumulated in the grid is no longer in use, while the obsolete share does not exceed 5% in the city of Linköping. For managers of local power grids, recovery of hibernating cables could be beneficial if integrated with other maintenance work on the grid. At the present price of copper, however, separate recovery of obsolete cables is not economically justified.  相似文献   
809.
Previous studies on arthropods showed that seasonality and parity in breeding considerably impact the direction of sex differences in immunocompetence, and it has been suggested that life span and the time window available for breeding play key roles in shaping sex-differences in immunity. One proposed mechanism behind this phenomenon is differential investment into life history traits in sexes. Here, we tested whether in a seasonally breeding semelparous arthropod sexes differ in their immunocompetence, predicting that females would show weaker immune response than males. We compared encapsulation efficiency (a well-established and widely used method for assessing immunocompetence) of freshly matured, virgin males and females of the lycosid spider Pardosa agrestis (Westring, 1861). On average, males mounted stronger immune response than females and the extent of encapsulation was positively associated with prosoma length in males, but not in females. Also, time until maturation was positively related to the extent of encapsulation in both sexes, but did not significantly affect adult prosoma length. We propose that sex-difference in encapsulation is likely shaped by combined effects of relatively higher costs of reproduction in females, narrow time window of reproductive activity, and the absence of trade-off between current and future reproduction.  相似文献   
810.
Recent studies on ecological networks have quantified the contribution of ecological, historical, and evolutionary factors on the structure of local communities of interacting species. However, the influence of species’ biogeographical traits, such as migratory habits or phylogeographical history, on ecological networks is poorly understood. Meta-networks, i.e., networks that cover large spatial extensions and include species not co-occurring locally, enable us to investigate mechanisms that operate at larger spatial scales such as migratory patterns or phylogeographical distributions, as well as indirect relationships among species through shared partners. Using a meta-network of hummingbird-plant interaction across Mexico, we illustrate the usefulness of this approach by investigating (1) how biogeographical and morphological factors associate with observed interactions and (2) how species-specific biogeographical characteristics associate with species’ network roles. Our results show that all studied hummingbird and plant species in the meta-network were interrelated, either directly or through shared partners. The meta-network was structured into modules, resulting from hummingbirds and plants interacting preferentially with subsets of species, which differed in biogeographical, and, to a lesser extent, morphological traits. Furthermore, migrants and hummingbirds from Nearctic, Transition, and widespread regions had a higher topological importance in the meta-network. Our study illustrates how meta-networks may contribute to our current knowledge on species’ biogeographical traits and biotic interactions, providing a perspective complementary to local-scale networks.  相似文献   
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