10%大灭微胶囊悬浮剂现场灭蚊效果观察

目的测试10%大灭微胶囊悬浮剂对蚊虫的滞留药效。方法现场灭蚊实验。结果 2个浓度组0.02、0.03 g a.i/m2在60 d内对蚊虫的滞留杀灭效果显著,同时2个浓度组间的灭蚊效果没有明显差异。结论 10%大灭微胶囊悬浮剂对蚊虫具有良好的滞留杀灭效果,值得推广应用。

大灭灵防治菜青虫试验总结

近年来随着产业结构的调整，蔬菜面积的不断扩大，菜青虫（Pieris rapae Linnaeus)的危害逐年加重，迫切需要寻求有效的药剂进行防治。为验证4．5％大灭灵乳油对菜青虫的防治效果及经济用量，特于1999年进行了本试验，现将试验结果整理如下。

两种杀虫剂浸泡蚊帐现场杀灭效果观察

目的在苏丹维和区观察比较奋斗呐和大灭杀虫剂浸泡蚊帐对蚊、蝇和其他昆虫的现场杀灭效果。方法选用奋斗呐(30mg.ai/m2)和大灭(20mg.ai/m2)浸泡军用蚊帐,检测对蚊、蝇和其他昆虫的杀灭效果。结果大灭浸泡蚊帐后第27天,对蚊类还具有较好的杀灭效果;奋斗呐浸泡蚊帐后第21天的杀灭效果明显下降,帐顶死蚊数仅为浸泡蚊帐第9天的33%。比较大灭组与奋斗呐组第21天帐顶蚊(蚊:Z=2.373,P=0.015)和第24天帐顶蝇及其他昆虫死亡数(蝇:Z=1.783,P=0.047;其他昆虫:Z=2.096,P=0.026)差异均有统计学意义,前者死亡数明显较后者为多。结论2种杀虫剂浸泡蚊帐后均能达到防治有害昆虫的目的,但大灭的持效时间更长,效果更好些。

现场灭蟑螂效果观察

蟑螂(蜚蠊)是危害比较严重的家栖卫生害虫之一.由于它的生活周期短,繁殖速度快,适应性强,在各种环境中都极易生存.已知有4000多种蟑螂遍布世界的每个角落,但绝大多数为野生种类,只有少数种群与人的关系密切.

科普新知

美最新研究推翻"月球有水"说称水浓度被夸大美国田纳西州行星地球科学学院主任拉里·泰勒最近在《自然》杂志上报告说,他们发现月球内部有水,大大增加了人们移居月球的希望;但仅仅时隔两周。

Development of a Multivalent Inactivated Vaccine against Pathogenic Escherichia coli Infection in Forest Musk Deer

A multivalent inactivated Escherichia coli vaccine for forest musk deer by using serotypes O4,O26,and O139 with Al（OH）3 adjuvant was prepared.The vaccine did not cause any adverse reactions in forest musk deer.The immunogenic effects of the vaccine were experimentally investigated in pregnant and young forest musk deer.The serum antibody titers of pregnant and young forest musk deer were determined by performing the micro-agglutination test.The serum antibody titers of pregnant forest musk deer were more stable from 35th to 68th d after the third vaccination,and the serum antibody titers of four pregnant forest musk deer were maintained 25,25,25,and 24 on 68th d after the third vaccination.Young forest musk deer showed serum antibody titers which were obtained due to nursing.Young forest musk deer were administered the first intramuscular vaccine injection at an age of approximately 60 days due to a fall in maternal antibody titers.The serum antibody titers of young forest musk deer were higher after the third vaccination and maintained at approximately the same level until they were 137 days old.The maternal antibodies and the antibodies produced by young forest musk deer could be helpful for protecting the young musk deer from the infections of pathogenic Escherichia coli strains（serotypes O4,O26,and O139）for 137 days after birth（during the nursing period and the period when the forest musk deer were susceptible to diseases）.

Using endocarp-remains of seeds of wild apricot Prunus armeniaca to identify rodent seed predators

Some rodent-dispersed seeds have a hard seed-coat(e.g.woody endocarp).Specific scrapes or dental marks on the hard seed-coat left by rodents when they eat these seeds can be used to identify seed predators.In this study we measured the morphological traits of endocarp-remains of seeds of wild apricot Prunus armeniaca used by Chinese white-bellied rats Niviventor confucianus and Korean field mice Apodemus peninsulae.We established their Fisher's linear discriminant functions to separate endocarp-remains between the two predators.A total of 90.0% of the endocarp-remains left by Korean field mice and 88.0% of those left by Chinese white-bellied rats were correctly classified.The overall percentage of correct classification was 89.0%.One hundred and sixty endocarp-remains of unknown what species predated them were classified using the functions.The method may allow more reliable quantitative studies of the effects of Chinese white-bellied rats and Korean field mice on seed consumption and dispersal of wild apricot and this study might be used for reference in other studies of seed predators identification on hard seeds.

Numerical simulation of the structure and variation of upwelling off the east coast of Hainan Island using QuikSCAT winds

The spatial structure and variation of the upwelling in the waters east and northeast of Hainan Island, China during 2000-2007 were investigated using a nested high-resolution Princeton Ocean Model (POM) forced by QuikSCAT winds. The model produced good simulations of the summer upwelling and the seasonal and annual variability. Strong upwelling occurs from mid-July to mid-August with a peak east of Hainan Island associated with the southwesterly monsoon in the South China Sea. Sensitivity experiments indicated that when the local wind stress controls the variability of the upwelling, the large-scale circulation significantly enhances the upwelling northeast of Hainan Island by inducing a local upwelling and transporting cold water northeast-ward along the island's east coast. The joint effects of the local wind stress and large-scale circulation result in stronger upwelling northeast of Hainan Island. This implies that the annual variation of the upwelling northeast of Hainan Island is controlled not only by the local alongshore wind stress but also by the large-scale circulation. This result will help us investigate the decadal variation of the upwelling in this region in the future.

Development of an Inactivated Iridovirus Vaccine Against Turbot Viral Reddish Body Syndrome

Turbot(Scophthalmus maximus L.) reddish body iridovirus(TRBIV) was propagated in turbot fin cells(TF cells) and inactivated as the TRBIV vaccine with its protection efficiency evaluated in this study.TF cells were cultured in 10% bovine calf serum(BCS)-containing MEM medium(pH7.0) at 22℃,in which TRBIV propagated to a titer as high as 105.6 TCID50 mL-1.The TRBIV was inactivated with 0.1% formalin and formulated with 0.5% aluminum hydroxide.The inactivated vaccine caused neither cytopathogenic effect(CPE) on TF cells nor pathogenic effect on turbots.After being administered with the vaccine twice via muscle injection,the turbot developed high-tittered TRBIV neutralizing antibodies in a dose-dependent manner.The vaccine protected the turbot from dying with an immunoprotection rate of 83.3% as was determined via subcutaneous vaccination in the laboratory and 90.5% via bath vaccination in turbot farms,respectively.The inactivated vaccine was very immunogenic,efficiently preventing tur-bot from death.It holds the potential of being applied in aquaculture.

中国科学家主导的“鸟类起源”研究被Science杂志评为2014年度十项重大科学进展

2014年岁末,我国古生物学家主导的'鸟类起源'研究入选国际权威刊物Science杂志年度十项重大科学进展。科学家对20多年来新发现的、主要产自中国的化石的研究表明,羽毛这样的类似鸟类的特征,实际上早在最早的鸟类出现以前,就已经在不同的恐龙类群中多次重复出现。目前看来,羽毛不仅仅是用于飞翔,也用于保暖、展示,也可能有保持平衡的作用。另外,研究也发现恐龙向鸟类的进化中身体逐渐变小,同时骨骼逐渐变得纤细。

Mass extinction and Pangea integration during the Paleozoic-Mesozoic transition

The greatest Phanerozoic mass extinction happened at the end-Permian to earliest Triassic. About 95% species, 82% genera, and more than half families became extinct, constituting the sole macro-mass extinction in geological history. This event not only caused the great extinction but also destroyed the 200 Myr-long Paleozoic marine ecosystem, prompted its transition to Mesozoic ecosystem, and induced coal gap on land as well as reef gap and chert gap in ocean. The biotic crisis during the Paleozoic-Mesozoic transition was a long process of co-evolution between geospheres and biosphere. The event sequence at the Permian-Triassic boundary （PTB） reveals two-episodic pattern of rapidly deteriorating global changes and biotic mass ex- tinction and the intimate relationship between them. The severe global changes coupling multiple geospheres may have affect- ed the Pangea integration on the Earth＇s surface spheres, which include： the Pangea integration→enhanced mountain height and basin depth, changes of wind and ocean current systems; enhanced ocean basin depth→the greatest Phanerozoic regression at PTB, disappearance of epeiric seas and subsequent rapid transgression; the Pangea integration→thermal isolation effect of continental lithosphere and decrease of mid-ocean ridges→development of continental volcanism; two-episode volcanism causing LIPs of the Emeishan Basalt and the Siberian Trap （25%251 Ma）→global warming and mass extinction; continental aridification and replacement of monsoon system by latitudinal wind system→destruction of vegetation; enhanced weathering and CH4 emission→negative excursion of δ^13C; mantle plume→crust doming→regression; possible relation between the Illawarra magnetic reversal and the PTB extinction, and so on. Mantle plume produced the Late Permian LIPs and mantle convection may have caused the process of the Pangea integration. Subduction, delamination, and accumulation of the earth＇s cool lithospheric material at the ＂D＂ layer of CMB started mantle plume by heat compensation and disturbed the outer core ther- too-convection, and the latter in turn would generate the mid-Permian geomagnetic reversal. These core and mantle perturbations may have caused the Pangea integration and two successive LIPs in the Permian, and probably finally the mass extinction at the PTB.

The large increase of δ^(13)C_(carb)-depth gradient and the end-Permian mass extinction

Carbonate carbon isotope （δ^13Ccarb） has received considerable attention in the Permian-Triassic transition for its rapid negative shift coinciding with the great end-Permian mass extinction event. The mechanism has long been debated for such a c~ δ^13Ccarb negative excursion through the end-Permian crisis and subsequent large perturbations in the entire Early Triassic. A δ^13Ccarb depth gradient is observed at the Permian-Triassic boundary sections of different water-depths, i.e., the Yangou, Meishan, and Shangsi sections, and such a large δ^13Ccarb-depth gradient near the end-Permian mass extinction horizon is believed to result from a stratified Paleotethys Ocean with widespread anoxic/euxinic deep water. The evolution of δ^13Ccarb-depth gradient com- bined with paleontological and geochemical data suggests that abundant cyanobacteria and vigorous biological pump in the immediate aftermath of the end-Permian extinction would be the main cause of the large δ^13Ccarb-depth gradient, and the enhanced continental weathering with the mass extinction on land provides a mass amount of nutriment for the flourishing cyanobacteria. Photic zone anoxia/euxinia from the onset of chemocline upward excursion might be the direct cause for the mass extinction whereas the instability of chemocline in the stratified Early Triassic ocean would be the reason for the delayed and involuted biotic recovery.

End-Guadalupian mass extinction and negative carbon isotope excursion at Xiaojiaba,Guangyuan,Sichuan

The end-Paleozoic biotic crisis is characterized by two-phase mass extinctions;the first strike,resulting in a large decline of sessile benthos in shallow marine environments,occurred at the end-Guadalupian time.In order to explore the mechanism of organisms' demise,detailed analyses of depositional facies,fossil record,and carbonate carbon isotopic variations were carried out on a Maokou-Wujiaping boundary succession in northwestern Sichuan,SW China.Our data reveal a negative carbon isotopic excursion across the boundary;the gradual excursion with relatively low amplitude(2.15‰) favors a long-term influx of isotopically light 12 C sourced by the Emeishan basalt trap,rather than by rapid releasing of gas hydrate.The temporal coincidence of the beginning of accelerated negative carbon isotopic excursion with onsets of sea-level fall and massive biotic demise suggests a cause-effect link between them.Intensive volcanic activity of the Emeishan trap and sea-level fall could have resulted in detrimental environmental stresses and habitat loss for organisms,particularly for those benthic dwellers,leading to their subsequent massive extinction.

Positron-Electron Annihilation Process in(2,2)-Difluoropropane Molecule

The positron-electron annihilation process in(2,2)-difluoropropane molecule and the corresponding gammaray spectra are studied by quantum chemistry method.The positrophilic electrons in(2,2)-difluoropropane molecule are found for the first time.The theoretical predictions show that the outermost 2s electrons of fluoride atoms play an important role in positron-electron annihilation process of(2,2)-difluoropropane.In the present scheme,the correlation coefficient between the theoretical gamma-ray spectra and the experiments can be 99%.The present study gives an alternative annihilation model for positron-electron pair in larger molecules.