Atmospheric pollution levels in China are increasing quickly. Experience from other polluted regions shows that tree growth could be affected, but long-term effects of N deposition and soil acidification on Chinese forests remain mostly unknown. Soil acidification and N deposition were simulated for Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.) plantations managed for three consecutive 20-year rotations in southeastern China. A factorial experiment combined four rain pH levels (2.5, 4.0, 5.6, and 7.0), four N deposition rates (1, 7.5, 15, and 30 kg N·ha -1 ·year -1 ), and two site qualities (poor and rich). Results indicate that atmospheric pollution effects are not immediate, but after one to two rotations, soil acidification effects could reduce ecosystem C pools significantly (-25% and -11% in poor and rich sites, respectively). N deposition rates above 15 kg N·ha -1 ·year -1 could offset some of the negative effects of soil acidification and lead to more ecosystem C (19 and 28 Mg C·ha -1 more in poor and rich sites, respectively, than in low N deposition). However, at high N deposition rates (>15 kg N·ha -1 ·year -1 ), N leaching losses could greatly increase, reaching 75 kg N·ha -1 ·year -1 . Moderate N deposition could increase tree biomass production and soil organic mass, resulting in increased ecosystem C, but these gains could be associated with important N leaching. Atmospheric pollution could also result in the long term in nutrient imbalances and additional ecological issues (i.e., biodiversity loss, eutrophication, etc.) not studied here.Résumé : Les niveaux de pollution atmosphérique augmentent rapidement en Chine. L'expérience d'autres régions aux prises avec la pollution montre que la croissance des arbres pourrait être ralentie mais les effets à long terme des dépôts azotés (N) et de l'acidification des sols dans les forêts chinoises sont pratiquement inconnus. L'acidification du sol et les dépôts de N ont été simulés dans des plantations de sapin de Chine (Cunninghamia lanceolata (Lamb.) Hook.) aménagées pendant trois rotations consécutives d'une durée de 20 ans dans le sud-est de la Chine. Une expérience factorielle a combiné quatre niveaux de pluie acide (pH 2,5, 4,0, 5,6 et 7,0), quatre taux de déposition de N (1, 7,5, 15 et 30 kg N·ha -1 ·an -1 ) et deux qualités de station (pauvre et riche). Les résultats montrent que les effets de la pollution atmosphérique ne sont pas immé-diats, mais qu'après une à deux rotations, les effets de l'acidification du sol pouvaient réduire de façon significative les ré-serves de carbone (C) de l'écosystème (-25 et -11 % respectivement dans les stations pauvres et riches). Les taux de déposition de N plus élevés que 15 kg N·ha -1 ·an -1 pouvaient atténuer certains des effets négatifs de l'acidification du sol et ont mené à plus de C de l'écosystème (19 et 28 Mg C·ha -1 de plus respectivement dans les stations pauvres et riches qu'avec un faible taux de déposition de N). Cependant, les pertes de N par lessivage pouvaient augmenter de façon importante, ju...

The commonly used inhalation anesthetic, isoflurane, can permeate rapidly through the placental barrier and thus cause toxicity to the central nervous system of the developing fetus. In this study, we treated pregnant mice with clinically relevant concentration of isoflurane early on in development (days 3.5-6.5), and then found that the fetus growth was inhibited by isoflurane. We further used the mouse embryonic stem cell (mES cell) to be the early development model to investigate the mechanism of the embryotoxicity of isoflurane and found that isoflurane inhibited self-renewal of mES cells. In addition, neuronal differentiation from the mES cells treated with isoflurane was also inhibited. Overexpression of E-cadherin attenuated the effects of isoflurane on selfrenewal and the subsequent neuronal differentiation. We also found that miR-9 can be upregulated by isoflurane. Overexpression of miR-9 inhibited the self-renewal and subsequent neuronal differentiation. E-cadherin was directly targeted by miR-9. Overexpression of E-cadherin can abolish the function of miR-9 or isoflurane on selfrenewal and subsequent neuronal differentiation. These data suggested that isoflurane inhibits self-renewal and neuronal differentiation of mES cells, possibly by regulating the miR-9-E-cadherin signaling. The result of the current study may provide a novel idea for preventing the toxicity of inhalation anesthetics in the developing fetal brain in clinical practice when pregnant women accept nonobstetric surgery under inhalation general anesthesia.

Water mist is one of the effective candidates for halon replacement used in electrical environment fire protection. Water mist additives may greatly enhance fire suppression effectiveness. In electrical environment, electrical breakdown field strength (E) is one of the important factors that control the performance of electrical equipment. In this study the variation principles of electrical breakdown field strength and the electrical characteristics of MC additives were investigated by electrode discharging experiments. Experimental results showed that electrical breakdown field strength was impacted obviously by the conductive metal ions and insulated fluorocarbon surfactants in MC additives. The attenuation percentages of E in different experimental cases were described, thus providing scientific guidance for the use of water mist and MC additives in electrical fire suppression.

In multithreaded programming, locks are frequently used as a mechanism for synchronization. Because today's operating systems do not consider lock usage as a scheduling criterion, scheduling decisions can be unfavorable to multithreaded applications, leading to performance issues such as convoying and heavy lock contention in systems with multiple processors. Previous efforts to address these issues (e.g., transactional memory, lock-free data structure) often treat scheduling decisions as "a fact of life," and therefore these solutions try to cope with the consequences of undesirable scheduling instead of dealing with the problem directly. In this paper, we introduce Contention-Aware Scheduler (CA-Scheduler) , which is designed to support efficient execution of large multithreaded Java applications in multiprocessor systems. Our proposed scheduler employs a scheduling policy that reduces lock contention. As will be shown in this paper, our prototype implementation of the CA-Scheduler in Linux and Sun HotSpot virtual machine only incurs 3.5% runtime overhead, while the overall performance differences, when compared with a system with no contention awareness, range from a degradation of 3% in a small multithreaded benchmark to an improvement of 15% in a large Java application server benchmark.