The outbreak pattern of the SARS cases in Asia

The severe acute respiratory syndrome (SARS) caused tremendous damage to many Asia countries, especially China. The transmission process and outbreak pattern of SARS is still not well understood. This study aims to find a simple model to describe the outbreak pattern of SARS cases by using SARS case data commonly released by governments. The outbreak pattern of cumulative SARS cases is expected to be a logistic type because the infection will be slowed down due to the increasing control effort by people and/or due to depletion of susceptible individuals. The increase rate of SARS cases is expected to decrease with the cumulative SARS cases, as described by the traditional logistical model, which is widely used in population dynamic studies. The instantaneous rate of increases were significantly and negatively correlated with the cumulative SARS cases in mainland of China (including Beijing, Hebei, Tianjin, Shanxi,the Autonomous Region of Inner Mongolia) and Singapore. The basic reproduction number R0 in Asia ranged from 2.0 to 5.6 (except for Taiwan, China). The R0 of Hebei and Tianjin were much higher than that of Singapore, Hongkong, Beijing, Shanxi, Inner Mongolia, indicating SARS virus might have originated differently or new mutations occurred during transmission. We demonstrated that the outbreaks of SARS in many regions of Asia were wall described by the logistic model, and the control measures implemented by governments are effective. The maximum instantaneous rate of increase, basic reproductive number, and maximum cumulative SARS cases were also calculated by using the logistic model.     

Phylogeny of SARS-CoV as inferred from complete genome comparison

SARS-CoV, as the pathogeny of severe acute respiratory syndrome (SARS), is a mystery that the origin of the virus is still unknown even a few isolates of the virus were completely sequenced. To explore the genesis of SARS-CoV,the FDOD method previously developed by us was applied to comparing complete genomes from 12 SARS-CoV isolates to those from 12 previously identified coronaviruses and an unrooted phyiogenetic tree was constructed. Our results show that all SARS-CoV isolates were clustered into a clique and previously identified coronaviruses formed the other clique. Meanwhile, the three groups of coronaviruses depart from each other clearly in our tree that is consistent with the results of prevenient papers. Differently, from the topology of the phylogenetic tree we found that SARS-CoV is more close to group 1 within genus coronavirus. The topology map also shows that the 12 SARS-CoV isolates may be divided into two groups determined by the association with the SARS-CoV from the Hotel M in Hong Kong that may give some information about the infectious relationship of the SARS.     

A novel method for ionizing radiation-induced RNA damage detection by poly（A）-tailing RT-PCR

Ionizing radiation (IR) causes severe cellular damage both directly and indirectly and disrupts RNA integrity. RNA strand breaks are the most frequent type of damage caused by IR. RNA damage is involved in the development of degenerative diseases, including Alzheimer’s disease and Parkinson’s disease. However, the mechanism of mRNA damage and any resulting pathophysiological outcomes are poorly understood. This is partly because there is a lack of sensitive tools to monitor damage randomly occurring in RNA,...     

Visible-infrared person re-identification using query related cluster

Visible-infrared person re-identification(VIPR), is a cross-modal retrieval task that searches a target from a gallery captured by cameras of different spectrums.The severe challenge for VIPR is the large intra-class variation caused by the modal discrepancy between visible and infrared images.For that, this paper proposes a query related cluster(QRC) method for VIPR.Firstly, this paper uses an attention mechanism to calculate the similarity relation between a visible query and infrared images w...     

Inconspicuous anchoring effects generated by false information

The impact of false information on numerical judgments was examined on young normal subjects by an event-related potential （ERP） experiment. To imitate the judgments in real world, we ensured the subjects acknowledged of the target task. The behavioral results found that both uncertain information and false information assimilated the final estimates： higher after higher anchors and lower after lower anchors; and false information caused a weaker anchoring bias than uncertain information. ERP results provided further electro- physiological evidence for the mechanism of anchoring. In the early phrase, it was an accessibility-dominated process in which two kinds of anchors elicited an N300 component related to the accessibility of anchors propositions. The knowledge relevant to targets joined the process in the late phrase, which caused a larger amplitude of late positive component （LPC） for implausible lower anchors than that for plausible higher anchors. Source analysis showed that medial frontal gyrus, whose activity was suggested to signal the need of adjust- ment, was more reliable to explain the LPC elicited by implausible lower anchors. Therefore, we suggest that accessibility is facilitated when the external anchor is consistent with the world knowledge, and adjustment is initiated when the external anchor is inconsistent.     

General design of Sutong Bridge

The main span of Sutong Bridge is a double-pylon, double-plane cable-stayed bridge with steel box girder, which has the world＇ s longest central span of 1 088 m within cable-stayed bridges. To overcome problems caused by severe meteorological conditions, perplexing hydrological conditions, deep buried bedrock and higher navigation level, many new technics and methods were created. Keys including structural system, steel box girder, stayed cable, tower, pier, tower foundation, collision avoidance system, wind-resistance, seismic-resistance, structural nonlinear response and structural static stability were presented individually in this paper.     

Review and prospect of transgenic rice research

Rice is one of the most important crops as the staple food for more than half of the world＇s population. Rice improvement has achieved remarkable success in the past half-century, with the yield doubled in most parts of the world and even tripled in certain regions, which has contributed greatly to food security globally. Rapid population growth and economic development pose a constantly increased food requirement. However, rice yield has been hovering in the past decade, which is mainly caused by the absence of novel breeding technologies, reduction of genetic diversity of rice cultivars, and serious yield loss due to increasingly severe occurrences of insects, diseases, and abiotic stresses. To address these challenges, Chinese scientists proposed a novel rice breeding goal of developing Green Super Rice to improve rice varieties and realize the sustainable development of agriculture, by focusing on the following 5 classes of traits： insect and disease resistance, drought-tolerance, nutrient-use effi- ciency, quality and yield potential. As a modern breeding approach, transgenic strategy will play an important role in realizing the goal of Green Super Rice. Presently, many transgenic studies of rice have been conducted, and most of target traits are consistent with the goal of Green Super Rice. In this paper, we firstly review technical advances of rice transformation, and then outline the main progress in transgenic rice research with respect to the most important traits： insect and disease-resistance, drought-tolerance, nutrient-use efficiency, quality, yield potential and herbicide-tolerance. The prospects of developing transgenic rice are also discussed.     

Control dynamics of severe acute respiratory syndrome transmission

Severe acute respiratory syndrome (SARS) is a serious disease with many puzzling features. We present a simple, dynamic model to assess the epidemic potential of SARS and the effectiveness of control measures. With this model, we analysed the SARS epidemic data in Beijing.The data fitting gives the basic case reproduction number of 2.16 leading to the outbreak, and the variation of the effective reproduction number reflecting the control effect. Noticeably, our study shows that the response time and the strength of control measures have significant effects on the scale of the outbreak and the lasting time of the epidemic.     

Bioinformatical study on the proteomics and evolution of SARS-CoV

A novel coronavirus has been identified as the causative agent of the severe acute respiratory syndrome (SARS). For all the SARS-CoV associated proteins derivated from the SARS-CoV genome, the physiochemical properties such as the molecular weight, isoelectric point and extinction coefficient of each protein were calculated. The transmembrane segments and subeellular localization (SubLoeation) prediction and conserved protein motifs search against database were employed to analyze the function of SARS-CoV proteins. Also, the homology protein sequence alignment and evolutionary distance matrix calculation between SARS-CoV associated proteins and the corresponding proteins of other coronaviruses were employed to identify the classification and phylogenetic relationship between SARS-CoV and other coronaviruses. The results showed that SARS-CoV is a novel coronavirus which is different from any of the three previously known groups of coronviruses, but it is closer to BoCoV and MHV than to other coronaviruses. This study is in aid of experimental determination of SARS-CoV proteomics and the development of antiviral vaccine.     

变化中的英语词汇

The English language is perhaps thegreatest language in the world,spoken na-tively by over a quarter of a billion peopleand as a second language by many millionsmore.It is a world language.The Englishlanguage of today reflects many centuries ofdevelopment.Political and social events,in     

Groundwater protection： What can we learn from Germany？

For drinking water security the German waterworks proceed on a comprehensive concept, i.e., the protection of all the regions from the recharge area to the client. It includes the protection of the recharge area by a precautionary management, a safe water treatment, a strict maintenance of the water distribution network, continuous control and an intensive training of staff. Groundwater protection zones together with effective regulations and control play a very important role. Three protection zones with different restrictions in land-use are distinguished. Water in reservoirs and lakes is also protected by Surface Water Protection Zones. Within the surrounding area the land-use is controlled, too. Special treatment is necessary if acidification happens caused by acid rain, or eutrophication caused by the inflow of sewage. Very important is the collaboration between waterworks and the farmers cultivating land in the recharge area in order to execute water-protecting ecological farming with the aim to reduce the application of fertilizers and plant protection agents. Probable financial losses have to be compensated by the waterworks.     

The DNA concentration effect on DNA radiation damage induced by 7Li ions and γ rays

To evaluate the influence of the DNA concentration in the aqueous solution on DNA radiation damage, the plasmid DNA in the presence or absence of Mannitol (scavenger of free radical OH·) was irradiated by 7Li ions and γ rays at various DNA concentrations. Gel electrophoresis analysis revealed that the DNA damage of single and double strand breaks induced by irradiation became more severe at lower DNA concentration. In the condition of γ-ray irradiation, most of double strand breaks (DSB) damage was neutralized and less associated with DNA concentration in the presence of mannitol. However, under 7Li irradiation, DSB damage could not be cleared by mannitol but was gradually aggravated with decreasing DNA concentrations. These findings imply that under low-LET irradiation, most of the DSB damage is generated by free radical OH? diffusion, and thus may be counteracted by scavengers, while at higher-LET irradiation, quite a fraction of DSB induction is caused by direct ionizing energy deposi- tion of heavy ions, which cannot be eliminated. This work also indicates that the proportion between free radical damage and direct ionizing damage is a constant which is independent of DNA concentra- tion when the DNA concentration is under a certain value (50 ng/μL). Our study sheds light on the un- derlying mechanisms in the DNA radiation damage process.     

Effect of welding parameters on the heat-affected zone of AISI409 ferritic stainless steel

One of the main problems during the welding of ferritic stainless steels is severe grain growth within the heat-affected zone (HAZ). In the present study, the microstructural characteristics of tungsten inert gas (TIG) welded AISI409 ferritic stainless steel were investigated by electron backscattered diffraction (EBSD), and the effects of welding parameters on the grain size, local misorientation, and low-angle grain boundaries were studied. A 3-D finite element model (FEM) was developed to predict the effects of welding parameters on the holding time of the HAZ above the critical temperature of grain growth. It is found that the base metal is not fully recrystallized. During the welding, complete recrystallization is followed by severe grain growth. A decrease in the number of low-angle grain boundaries is observed within the HAZ. FEM results show that the final state of residual strains is caused by competition between welding plastic strains and their release by recrystallization. Still, the decisive factor for grain growth is heat input.     

Protein Subcellular Localization Prediction and Genomic Polymorphism Analysis of the SARS Coronaviru

The cause of severe acute respiratory syndrome (SARS) has been identified as a new coronavirus (CoV). Several sequences of the complete genome of SARS-CoV have been determined. The subcellular localization (SubLocation) of annotated open-reading frames of the SARS-CoV genome was predicted using a support vector machine. Several gene products were predicted to locate in the Golgi body and cell nucleus. The SubLocation information was combined with predicted transmembrane information to develop a model of the viral life cycle. The results show that this information can be used to predict the functions of genes and even the virus pathogenesis. In addition, the entire SARS viral genome sequences currentlyav ailable in GenBank were compared to identify the sequence variations among different isolates. Some variations in the Hong Kong strains may be related to the special clinical manifestations and provide clues for understanding the relationship between gene functions and evolution. These variations reflect the evolution of the SARS virus in human populations and may help development of a vaccine.     

The DNA concentration effect on DNA radiation damage induced by <Superscript>7</Superscript>Li ions and γ rays

To evaluate the influence of the DNA concentration in the aqueous solution on DNA radiation damage, the plasmid DNA in the presence or absence of Mannitol （scavenger of free radical OH.） was irradiated by ^7Li ions and γ rays at various DNA concentrations. Gel electrophoresis analysis revealed that the DNA damage of single and double strand breaks induced by irradiation became more severe at lower DNA concentration. In the condition of γ-ray irradiation, most of double strand breaks （DSB） damage was neutralized and less associated with DNA concentration in the presence of mannitol. However, under ^7Li irradiation, DSB damage could not be cleared by mannitol but was gradually aggravated with decreasing DNA concentrations. These findings imply that under low-LET irradiation, most of the DSB damage is generated by free radical OH·diffusion, and thus may be counteracted by scavengers, while at higher-LET irradiation, quite a fraction of DSB induction is caused by direct ionizing energy deposition of heavy ions, which cannot be eliminated. This work also indicates that the proportion between free radical damage and direct ionizing damage is s constant which is independent of DNA concentration when the DNA concentration is under a certain value （50ng/μL）. Our study sheds light on the un- derlying mechanisms in the DNA radiation damage process.     

Information for Authors

Chinese Science Bulletin (CSB) is a multidisciplinary academic journal supervised by the Chinese Academy of Sciences and co-sponsored by the Chinese Academy of Sciences and National Natural Science Foundation of China. Its mission is to encourage communication of basic and innovative research results of high quality in the fields of natural sciences and high technologies, especially focusing on breakthroughs by the Chinese scientists. All papers should be intelligible for a broad scientific audience. CSB is published three times every month from 2010. Contributions are invited from researchers all over the world.     

Comparison of Chinese and Foreign Urban Public Security Treatment Mechanisms and Analysis of Policy References

1Basic Types and Characteristics ofUrban Public Security Incidents[1,2]1·1Concept of Urban Public SecurityIncidentsUrban public security incident is a generalreference to the urban public security incidentscaused by artificially created factors,variousurban public security incidents caused by naturalfactors,and the incidents caused by the inter-acted performance of artificially created factorsand natural factors.The development andprogressive course of modern society is also thecourse of …     

结晶器内电磁搅拌对结晶器表面负偏析影响的模型预测

Aiming at the problem of negative segregation under a bloom surface, a coupling macrosegregation model considering electromagnetic field, flow, heat, and solute transport was established based on the volume average method to study the effect of in-mold electromagnetic stirring (M-EMS) on the negative segregation under the bloom surface. In the model, the influence of dendrite structure on the flow and solute transport was described by the change of permeability. The model was validated by the magnetic induction intensity of M-EMS and carbon segregation experiment. The results show that the solute C in the solidified shell in the turbulent zone of the bloom undergoes two negative segregations, whereby the first is caused by nozzle jet, and the second by the M-EMS. The severities of the negative segregation caused by M-EMS at different currents and frequencies are also different, and the larger the current is, or the smaller the frequency is, the more serious will be the negative segregation. With the M-EMS, the solute C distribution in the liquid phase of the bloom is more uniform, but the mass fraction of C in the liquid phase is higher than that without M-EMS.     

Transient reconnection caused by non-homogenous dynamic pressure

It is proposed that local and transient reconnection in the plasma boundary layer can be caused by the impact and switch-off of non-homogenous dynamic pressure. Magnetohydrodynamic simulation is used to investigate the reconnection processes in these two cases. It is found that if the inflow is homogeneous, the reconnection will not take place; if the inflow is a shearing flow, no matter how great the shear of the flow is, the reconnection can be caused either during or after the impacting period. It is pointed out that a sudden stop of external force may be an important triggering mechanism of energy transformation and reconnection in the plasma boundary layer region.