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With the aim to contribute to humanitarian response to disasters and violent events, scientists have proposed the development of analytical tools that could identify emergency events in real-time, using mobile phone data. The assumption is that dramatic and discrete changes in behavior, measured with mobile phone data, will indicate extreme events. In this study, we propose an efficient system for spatiotemporal detection of behavioral anomalies from mobile phone data and compare sites with behavioral anomalies to an extensive database of emergency and non-emergency events in Rwanda. Our methodology successfully captures anomalous behavioral patterns associated with a broad range of events, from religious and official holidays to earthquakes, floods, violence against civilians and protests. Our results suggest that human behavioral responses to extreme events are complex and multi-dimensional, including extreme increases and decreases in both calling and movement behaviors. We also find significant temporal and spatial variance in responses to extreme events. Our behavioral anomaly detection system and extensive discussion of results are a significant contribution to the long-term project of creating an effective real-time event detection system with mobile phone data and we discuss the implications of our findings for future research to this end.  相似文献   
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Co-administration of dextromethorphan (DM) with morphine during pregnancy and throughout lactation has been found to reduce morphine physical dependence and tolerance in rat offspring. No evidence was presented, however, for the effect of DM co-administered with morphine during pregnancy on morphine-induced reward and behavioral sensitization (possibly related to the potential to induce morphine addiction) in morphine-exposed offspring. Conditioned place preference and locomotor activity tests revealed that the p60 male offspring of chronic morphine-treated female rats were more vulnerable to morphine-induced reward and behavioral sensitization. The administration of a low dose of morphine (1 mg/kg, i.p.) in these male offspring also increased the dopamine and serotonin turnover rates in the nucleus accumbens, which implied that they were more sensitive to morphine. Co-administration of DM with morphine in the dams prevented this adverse effect of morphine in the offspring rats. Thus, DM may possibly have a great potential in the prevention of higher vulnerability to psychological dependence of morphine in the offspring of morphine-addicted mothers.  相似文献   
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Lai YJ  Huang EY  Yeh HI  Chen YL  Lin JJ  Lin CI 《Life sciences》2008,83(7-8):272-283
We have previously shown that left atrial-pulmonary vein tissue (LA-PV) can generate reentrant arrhythmias (atrial fibrillation, AF) in wild-type (mXinalpha+/+) but not in mXinalpha-null (mXinalpha-/-) mice. With the present experiments, we investigated the arrhythmogenic activity and the underlying mechanisms in mXinalpha+/+ vs. mXinalpha-/- LA-PV. Electrical activity and conduction velocity (CV) were recorded in LA-PV by means of a MED64 system. CV was significantly faster in mXinalpha+/+ than in mXinalpha-/- LA-PV and it was increased by 1 muM isoproterenol (ISO). AF could be induced by fast pacing in the mXinalpha+/+ but not in mXinalpha-/- LA-PV where automatic rhythms could occur. ISO increased the incidence of AF in Xinalpha+/+ whereas it increased that of automatic rhythms in mXinalpha-/- LA-PV. In LA-PV with the right atrium attached (RA-LA-PV), automatic rhythms occurred in all preparations. In mXinalpha+/+ RA-LA-PV simultaneously treated with ISO, strophanthidin and atropine, the incidence of the automatic rhythm was about the same, but AF increased significantly. In contrast, in mXinalpha-/- RA-LA-PV under the same condition, the automatic rhythm was markedly enhanced, but still no AF occurred. Conventional microelectrode techniques showed a longer APD(90) and a less negative maximum diastolic potential (MDP) in mXinalpha-/- than mXinalpha+/+ LA-PV tissues. Whole-cell current clamp experiments also showed a less negative MDP in mXinalpha-/- vs. mXinalpha+/+ LA-PV cardiomyocytes. The fact that AF could be induced by fast pacing under several conditions in mXinalpha+/+ but not in mXinalpha-/- LA-PV preparations appears to be due to a slower CV, a prolonged APD(90), a less negative MDP and possibly larger areas of conduction block in mXinalpha-/- myocardial cells. In contrast, the non-impairment of automatic and triggered rhythms in mXinalpha-/- preparations may be due to the fact that the mechanisms underlying these rhythms do not involve cell-to-cell conduction.  相似文献   
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This is the first record of seed transmission of turnip yellow mosaic virus (TYMV) in oilseed and turnip rapes. The seed transmission of TYMV in a naturally infected winter turnip rape (Brassica napus var. silvestris) cultivar Perko PVH was investigated. By ELISA 1.6%, 3.2% and 8.3% seed transmission of the virus was found in seed of plants from three localities. The proportion of infected seeds produced by artificially infected plants of winter oilseed rape (Brassica napus ssp. oleifera) and winter turnip rape cultivars was determined. The virus transmission rate, expressed as the proportion of virus-infected plants which germinated from the seed was for the oilseed rape cvs Jet Neuf 0.1%, Solida 0.4%, Silesia 0.8%, Darmor 1.2%, SL-507 0.2%, SL-509 0.0% and for the winter turnip rape cv. Perko 1.5%. ELISA cannot be used in direct tests on bulk seed lots to estimate proportion of infected seed, but must be used on germinated seedlings.  相似文献   
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River ecosystem resilience to extreme flood events   总被引:1,自引:0,他引:1       下载免费PDF全文
Floods have a major influence in structuring river ecosystems. Considering projected increases in high‐magnitude rainfall events with climate change, major flooding events are expected to increase in many regions of the world. However, there is uncertainty about the effect of different flooding regimes and the importance of flood timing in structuring riverine habitats and their associated biotic communities. In addition, our understanding of community response is hindered by a lack of long‐term datasets to evaluate river ecosystem resilience to flooding. Here we show that in a river ecosystem studied for 30 years, a major winter flood reset the invertebrate community to a community similar to one that existed 15 years earlier. The community had not recovered to the preflood state when recurrent summer flooding 9 years later reset the ecosystem back to an even earlier community. Total macroinvertebrate density was reduced in the winter flood by an order of magnitude more than the summer flood. Meiofaunal invertebrates were more resilient to the flooding than macroinvertebrates, possibly due to their smaller body size facilitating greater access to in‐stream refugia. Pacific pink salmon escapement was markedly affected by the winter flood when eggs were developing in redds, compared to summer flooding, which occurred before the majority of eggs were laid. Our findings inform a proposed conceptual model of three possible responses to flooding by the invertebrate community in terms of switching to different states and effects on resilience to future flooding events. In a changing climate, understanding these responses is important for river managers to mitigate the biological impacts of extreme flooding effects.  相似文献   
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The distribution and morphology of antennal sensilla coeloconica in parasitic and predaceous biting midges were studied in females of Forcipomyia (feeding on the blood of frogs), Atrichopogon (feeding on haemolymph), Austroconops, Culicoides (feeding on the blood of birds and mammals) and Brachypogon (feeding on haemolymph and dissolved tissues of insects) (all: Diptera: Ceratopogonidae). A Lower Cretaceous female of Archiculicoides (Diptera: Ceratopogonidae) from Lebanese amber, which fed on the blood of unknown vertebrates, was also examined. In sensilla coeloconica ringed by microtrichia, the peg is grooved longitudinally and protrudes distinctly from the pit. We suggest that the microtrichia encircling the protruding peg form a structure resembling a picket fence in order to maintain a higher level of humidity, which facilitates the capture and transport of odour molecules through the channels in the peg wall. Sensilla coeloconica ringed by microtrichia function as very effective chemoreceptors in host‐ and prey‐seeking activity. During the evolution of Ceratopogonidae, sensilla coeloconica with a fence of microtrichia have evolved twice in groups feeding on the blood of vertebrates (i.e. in the basal lineage: Lower Cretaceous or earlier) and in the subgenus Lasiohelea of Forcipomyia (Palaeogene). Sensilla coeloconica ringed by microtrichia are described for the first time in the relict genus Austroconops.  相似文献   
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