The Internet of Things(IoT)has characteristics such as node mobility,node heterogeneity,link heterogeneity,and topology heterogeneity.In the face of the IoT characteristics and the explosive growth of IoT nodes,which ...The Internet of Things(IoT)has characteristics such as node mobility,node heterogeneity,link heterogeneity,and topology heterogeneity.In the face of the IoT characteristics and the explosive growth of IoT nodes,which brings about large-scale data processing requirements,edge computing architecture has become an emerging network architecture to support IoT applications due to its ability to provide powerful computing capabilities and good service functions.However,the defense mechanism of Edge Computing-enabled IoT Nodes(ECIoTNs)is still weak due to their limited resources,so that they are susceptible to malicious software spread,which can compromise data confidentiality and network service availability.Facing this situation,we put forward an epidemiology-based susceptible-curb-infectious-removed-dead(SCIRD)model.Then,we analyze the dynamics of ECIoTNs with different infection levels under different initial conditions to obtain the dynamic differential equations.Additionally,we establish the presence of equilibrium states in the SCIRD model.Furthermore,we conduct an analysis of the model’s stability and examine the conditions under which malicious software will either spread or disappear within Edge Computing-enabled IoT(ECIoT)networks.Lastly,we validate the efficacy and superiority of the SCIRD model through MATLAB simulations.These research findings offer a theoretical foundation for suppressing the propagation of malicious software in ECIoT networks.The experimental results indicate that the theoretical SCIRD model has instructive significance,deeply revealing the principles of malicious software propagation in ECIoT networks.This study solves a challenging security problem of ECIoT networks by determining the malicious software propagation threshold,which lays the foundation for buildingmore secure and reliable ECIoT networks.展开更多
The field of finance heavily relies on cybersecurity to safeguard its systems and clients from harmful software.The identification of malevolent code within financial software is vital for protecting both the financia...The field of finance heavily relies on cybersecurity to safeguard its systems and clients from harmful software.The identification of malevolent code within financial software is vital for protecting both the financial system and individual clients.Nevertheless,present detection models encounter limitations in their ability to identify malevolent code and its variations,all while encompassing a multitude of parameters.To overcome these obsta-cles,we introduce a lean model for classifying families of malevolent code,formulated on Ghost-DenseNet-SE.This model integrates the Ghost module,DenseNet,and the squeeze-and-excitation(SE)channel domain attention mechanism.It substitutes the standard convolutional layer in DenseNet with the Ghost module,thereby diminishing the model’s size and augmenting recognition speed.Additionally,the channel domain attention mechanism assigns distinctive weights to feature channels,facilitating the extraction of pivotal characteristics of malevolent code and bolstering detection precision.Experimental outcomes on the Malimg dataset indicate that the model attained an accuracy of 99.14%in discerning families of malevolent code,surpassing AlexNet(97.8%)and The visual geometry group network(VGGNet)(96.16%).The proposed model exhibits reduced parameters,leading to decreased model complexity alongside enhanced classification accuracy,rendering it a valuable asset for categorizing malevolent code.展开更多
In this editorial,I comment on the article by Zhang et al.To emphasize the importance of the topic,I discuss the relationship between the use of smart medical devices and mental health.Smart medical services have the ...In this editorial,I comment on the article by Zhang et al.To emphasize the importance of the topic,I discuss the relationship between the use of smart medical devices and mental health.Smart medical services have the potential to positively influence mental health by providing monitoring,insights,and inter-ventions.However,they also come with challenges that need to be addressed.Understanding the primary purpose for which individuals use these smart tech-nologies is essential to tailoring them to specific mental health needs and prefe-rences.展开更多
Codon usage is the selective and nonrandom use of synonymous codons to encode amino acids in genes for proteins. The analysis of codon usage may improve the understanding of cocion preferences between different specie...Codon usage is the selective and nonrandom use of synonymous codons to encode amino acids in genes for proteins. The analysis of codon usage may improve the understanding of cocion preferences between different species and allow to rebuild the codons of exogenous genes to increase the expression efficiency of exogenous genes, Here, codon DNA sequence (CDS) of four poplar species, including Populus tremuloides Michx., P. tomentosa Carr., P. deltoides Marsh., and P. trichocarpa Torr. & Gray., is used to analyze the relative frequency of synonymous codon (RFSC). High-frequency codons are selected by high-frequency (HF) codon analysis. The results indicate that the codon usage is common for all four poplar species and the codon preference is quite similar among the four poplar species. However, CCT encoding for Pro, and ACT coding for Thr are the preferred codons in P. tremuloides and P. tomentosa, whereas CCA coding for Pro, and ACA coding for Thr are preferred in P. deltoides and P. trichocarpa The codons such as TGC coding for Cys, TTC coding for Phe, and AAG coding for Lys, are preferred in the poplar species except P trichocarpa. GAG coding for Glu is preferred only in P deltoides, while the other three poplar species prefer to use GAA. The commonness of preferred codon allows exogenous gene designed by the preferred cocion of one of the different poplar species to be used in other poplar species.展开更多
Burkholderia mallei is regarded as a potential biological weapon by the Centers for Disease Control and Prevention. In this study, the main factors shaping codon usage in the genome of B. mallei ATCC 23344 were firstl...Burkholderia mallei is regarded as a potential biological weapon by the Centers for Disease Control and Prevention. In this study, the main factors shaping codon usage in the genome of B. mallei ATCC 23344 were firstly reported. The results showed that the primary trend in codon usage variation in the B. mallei is due to translational selection; while compositional mutation bias is relatively the weaker influence and the hydrophobicity of each protein and gene length are only the minor influences. At the same time, 21 codons defined firstly as 'optimal codons' might provide more useful information for the expression of target genes and development of a vaccine to prevent glanders.展开更多
The synonymous codon usage in the translational initiation and termination regions of genes of severe acute respiratory syndrome (SARS) coronavirus and five other viruses in Coronaviridae was systematically analyzed.T...The synonymous codon usage in the translational initiation and termination regions of genes of severe acute respiratory syndrome (SARS) coronavirus and five other viruses in Coronaviridae was systematically analyzed.The results indicate that most minor codons for these coronaviruses are preferentially used in the initial and terminal region.The minor codons preferentially used in the initial region are thought to have a negative effect on gene expression,which can be explained by the minor codon modulator hypothesis.It also indicates that the minor codons preferentially used in the terminal region may regulate the level of gene expression.The proposed results strongly imply that the minor codon modulator hypothesis can be applied to both some bacteria and some viruses.展开更多
Based on lawn function theory and urban planning perspectives, functions of urban lawns were analyzed, status and prospect of the multiple usages of lawn were revealed. Urban lawn was concluded as an important part of...Based on lawn function theory and urban planning perspectives, functions of urban lawns were analyzed, status and prospect of the multiple usages of lawn were revealed. Urban lawn was concluded as an important part of modern urban greening, moveover, it has been integrated in people's lives gradually by playing a significant role in people's work, studying, leisure, urban disaster prevention and mitigation. At the same time, problems rise from the multiple usages of lawn were discussed and improvement suggestions were put forward.展开更多
In this study, a comparative analysis of the codon usage bias was performed in Aeropyrum pernix K1 and two other phylogenetically related Crenarchaeota microorganisms (i.e., Pyrobaculum aerophilum str. IM2 and Sulfol...In this study, a comparative analysis of the codon usage bias was performed in Aeropyrum pernix K1 and two other phylogenetically related Crenarchaeota microorganisms (i.e., Pyrobaculum aerophilum str. IM2 and Sulfolobus acidocaldarius DSM 639). The results indicated that the synonymous codon usage in A. pernix K1 was less biased, which was highly correlated with the GC3s value. The codon usage patterns were phylogenetically conserved among these Crenarchaeota microorganisms. Comparatively, it is the species function rather than the gene function that determines their gene codon usage patterns. A. pernix K1, P. aerophilum str. IM2, and S. acidocaldarius DSM 639 live in differently extreme conditions. It is presumed that the hving environment played an important role in determining the codon usage pattern of these microorganisms. Besides, there was no strain-specific codon usage among these microorganisms. The extent of codon bias in A. pernix K1 and S. acidocaldarius DSM 639 were highly correlated with the gene expression level, but no such association was detected in P. aerophilum str. IM2 genomes.展开更多
Codon usage in chloroplast genome of six seed plants (Arabidopsis thaliana, Populus alba, Zea mays, Triticum aestivum, Pinus koraiensis and Cycas taitungensis) was analyzed to find general patterns of codon usage in...Codon usage in chloroplast genome of six seed plants (Arabidopsis thaliana, Populus alba, Zea mays, Triticum aestivum, Pinus koraiensis and Cycas taitungensis) was analyzed to find general patterns of codon usage in chloroplast genomes of seed plants. The results show that chloroplast genomes of the six seed plants had similar codon usage patterns, with a strong bias towards a high representation of NNA and NNT codons. In chloroplast genomes of the six seed plants, the effective number of codons (ENC) for most genes was similar to that of the expected ENC based on the GC content at the third codon position, but several genes with low ENC values were laying below the expected curve. All of these data indicate that codon usage was dominated by a mutational bias in chloroplast genomes of seed plants and that selection appeared to be limited to a subset of genes and to only subtly affect codon usage. Meantime, four, six, eight, nine, ten and 12 codons were defined as the optimal codons in chloroplast genomes of the six seed plants.展开更多
Apple(Malus×domestica) has been proposed as an important woody plant and the major cultivated fruit trees in temperate regions. Apple whole genome sequencing has been completed, which provided an excellent oppo...Apple(Malus×domestica) has been proposed as an important woody plant and the major cultivated fruit trees in temperate regions. Apple whole genome sequencing has been completed, which provided an excellent opportunity for genome-wide analysis of the synonymous codon usage patterns. In this study, a multivariate bioinformatics analysis was performed to reveal the characteristics of synonymous codon usage and the main factors affecting codon bias in apple. The neutrality, correspondence, and correlation analyses were performed by Codon W and SPSS(Statistical Product and Service Solutions) programs, indicating that the apple genome codon usage patterns were affected by mutational pressure and selective constraint. Meanwhile, coding sequence length and the hydrophobicity of proteins could also influence the codon usage patterns. In short, codon usage pattern analysis and determination of optimal codons has laid an important theoretical basis for genetic engineering, gene prediction and molecular evolution studies in apple.展开更多
[Objective] The objective of this study was to understand the codon usage bias pattern of banana pathogenesis-related 17 gene, Basic Secretory Protease gene(MaBSP). [Method] Relative codon usage patterns of MaBSP were...[Objective] The objective of this study was to understand the codon usage bias pattern of banana pathogenesis-related 17 gene, Basic Secretory Protease gene(MaBSP). [Method] Relative codon usage patterns of MaBSP were calculated using the software CodonW version 1.4.2. and the web-based tool(http://kazusa.or.jp/codon/).[Result] Our findings showed that C-ended and G-ended codons were the most preferential except the TER codon UGA which was coded for by just one codon. The ENc value, relationship between AT bias and GC bias, Random synonymous codon usage(RSCU) and CAI all showed that codon bias usage existed in MaBSP gene.[Conclusion] The codon usage patterns of MaBSP gene is principally influenced by natural selection in the third position. However, other multiple factors also influence this pattern.展开更多
Codon usage bias(CUB) is a unique property of genome which refers to non-random usage of synonymous codons in coding sequences. The present study makes an attempt to find out the pattern of CUB in chloroplast(cp) gene...Codon usage bias(CUB) is a unique property of genome which refers to non-random usage of synonymous codons in coding sequences. The present study makes an attempt to find out the pattern of CUB in chloroplast(cp) genes among three tea species, i.e., Camellia sinensis var. assamica(Assam tea), Camellia sinensis var. sinensis(Chinese tea) and Camellia pubicosta(wild tea species) as no work on CUB was reported earlier. To understand the patterns of codon usage among the cp genes of three tea groups, we used bioinformatic tools to investigate the protein coding sequences of cp genes. In our present study, the mean nucleobase T was the highest whereas C was the lowest in all the three tea groups. The overall AT content was more than GC content, i.e., genes were AT rich. The scaled chi-square(SCS) value indicated that the CUB of cp genes was low. The codon CGT(Arg) was over-represented in C. sinensis var. sinensis whereas GGA(Pro) was over-represented in C. pubicosta species. Heatmap study revealed that most of the GC ending codons showed positive correlations between codon usage and GC3 while AT ending codons exhibited negative correlations. From neutrality plot analysis, it was evident that natural selection had played a major role, while mutation pressure exerted a minor effect in the CUB of cp genes in three tea groups. Highly significant(P<0.01) positive correlation was found between SCS and synonymous codon usage order(SCUO) of cp genes which suggested that high expression of cp genes was associated with high degree of CUB.展开更多
The pattern of codon usage in the chloroplast genome of Populus alba was investigated. Correspondence analysis (a commonly used multivariate statistical approach) and method of effective number of codons (ENc)-plo...The pattern of codon usage in the chloroplast genome of Populus alba was investigated. Correspondence analysis (a commonly used multivariate statistical approach) and method of effective number of codons (ENc)-plot were conducted to analyze synonymous codon usage. The results of correspondence analysis showed that the distribution of genes on the major axis was significantly correlated with the frequency of use of G+C in synonymously variable third position of sense codon (GC3S), (r=0.349), and the positions of genes on the axis 2 and axis 3 were significantly correlated with CAI (r=-0.348, p〈0.01 and r=0.602, p〈0.01). The ENc for most genes was similar to that for the expected ENc based on the GC3s, but several genes with low ENc values were lying below the expected curve. All of these data indicated that codon usage was dominated by a mutational bias in chloroplast gcnome ofP. alba. The selection in nature for translational efficiency only played a minor role in shaping codon usage in the chloroplast genome ofP alba.展开更多
Future or smart community, which mainly refers to the development of community information and communication technology(ICT) platforms or devices, has received considerable attention from urban governments and scholar...Future or smart community, which mainly refers to the development of community information and communication technology(ICT) platforms or devices, has received considerable attention from urban governments and scholars. However, only a few studies have been conducted to test the actual effects of using these community ICT platforms or devices on the community satisfaction of residents. Therefore, the present study conducts a survey in 40 communities in Nanjing, China and uses a mixed linear regression model to determine the relationship between community ICT usage and community satisfaction. Results indicate that residents with high-level community ICT usage are more satisfied with their community than those with low-level community ICT usage. Moreover, evident differences are observed regarding the influence of new commodity, old commodity and affordable housing communities in Nanjing. These findings are meaningful for the construction and development of future communities.展开更多
Species diversity and ethno-medicinal usage of 39 species of invasive plants were explored in and around two protected areas, Khadimnagar National Park (KNP) and Rema-Kalenga Wildlife Sanctu- ary (RKWS), of northe...Species diversity and ethno-medicinal usage of 39 species of invasive plants were explored in and around two protected areas, Khadimnagar National Park (KNP) and Rema-Kalenga Wildlife Sanctu- ary (RKWS), of northeastern Bangladesh,. Status of invasive plants were investigated in 60 sample plots with 5 different habitat types, including forest, roadside, homestead, fallow land and others (ponds, canals, water logged areas, agricultural land, etc.). Data about the usage of invasive plants in traditional health care were collected through interviewing 110 households. Among the five habitat types, fallow land (28 species).possessed the highest number of species, followed by roadside (25 species), forest (23 species), homestead (22 species) and others (13 species). Based on the survey, invasive plants of study areas were also categorized into five degrees of invasiveness e.g., naturalized, introduced, possibly invasive, moderately invasive and highly invasive. Additionally, there is the linear trend between degrees of invasivaness and use percentage of invasive plants. Total 39 species of invasive plants belonging to 29 families were recorded, which are generally used to treat 37 diseases, ranging from simple headache to highly complicated eye and heart diseases. The majority of the species used by the local inhabitants were herbs (16 species), followed by some shrubs (11 species), climbers (5 species), trees (5 species) and grasses (2 species). The use percentage of aboveground plant parts were higher (70.58%) than that of underground plant parts (16.18%).展开更多
Spam is no longer just commercial unsolicited email messages that waste our time, it consumes network traffic and mail servers’ storage. Furthermore, spam has become a major component of several attack vectors includ...Spam is no longer just commercial unsolicited email messages that waste our time, it consumes network traffic and mail servers’ storage. Furthermore, spam has become a major component of several attack vectors including attacks such as phishing, cross-site scripting, cross-site request forgery and malware infection. Statistics show that the amount of spam containing malicious contents increased compared to the one advertising legitimate products and services. In this paper, the issue of spam detection is investigated with the aim to develop an efficient method to identify spam email based on the analysis of the content of email messages. We identify a set of features that have a considerable number of malicious related features. Our goal is to study the effect of these features in helping the classical classifiers in identifying spam emails. To make the problem more challenging, we developed spam classification models based on imbalanced data where spam emails form the rare class with only 16.5% of the total emails. Different metrics were utilized in the evaluation of the developed models. Results show noticeable improvement of spam classification models when trained by dataset that includes malicious related features.展开更多
Codon usage bias varies considerably among genomes and even within the genes of the same genome. In eukaryotic organisms, energy production in the form of oxidative phosphorylation (OXPHOS) is the only process under...Codon usage bias varies considerably among genomes and even within the genes of the same genome. In eukaryotic organisms, energy production in the form of oxidative phosphorylation (OXPHOS) is the only process under control of both nuclear and mitochondrial genomes. Although factors affecting codon usage in a single genome have been studied, this has not occurred when both interactional genomes are involved. Consequently, we investigated whether or not other factors influence codon usage of coevolved genes. We used Drosophila melanogaster as a model organism. Our χ^2 test on the number of codons of nuclear and mitochondrial genes involved in the OXPHOS system was significantly different (χ^2= 7945.16, P 〈 0.01). A plot of effective number of codons against GC3s content of nuclear genes showed that few genes lie on the expected curve, indicating that codon usage was random. Correspondence analysis indicated a significant correlation between axis 1 and codon adaptation index (R = 0.947, P 〈 0.01) in every nuclear gene sequence. Thus, codon usage bias of nuclear genes appeared to be affected by translational selection. Correlation between axis 1 coordinates and GC content (R = 0.814, P 〈 0.01) indicated that the codon usage of nuclear genes was also affected by GC composition. Analysis of mitochondrial genes did not reveal a significant correlation between axis 1 and any parameter. Statistical analyses indicated that codon usages of both nDNA and mtDNA were subjected to context-dependent mutations.展开更多
In order to study the spatiotemporal characteristics of the dockless bike sharing system(BSS)around urban rail transit stations,new normalized calculation methods are proposed to explore the temporal and spatial usage...In order to study the spatiotemporal characteristics of the dockless bike sharing system(BSS)around urban rail transit stations,new normalized calculation methods are proposed to explore the temporal and spatial usage patterns of the dockless BSS around rail transit stations by using 5-weekday dockless bike sharing trip data in Nanjing,China.First,the rail transit station area(RTSA)is defined by extracting shared bike trips with trip ends falling into the area.Then,the temporal and spatial decomposition methods are developed and two criterions are calculated,namely,normalized dynamic variation of bikes(NDVB)and normalized spatial distribution of trips(NSDT).Furthermore,the temporal and spatial usage patterns are clustered and the corresponding geographical distributions of shared bikes are determined.The results show that four temporal usage patterns and two spatial patterns of dockless BSS are finally identified.Area type(urban center and suburb)has a great influence on temporal usage patterns.Spatial usage patterns are irregular and affected by limited directions,adjacent rail transit stations and street networks.The findings can help form a better understanding of dockless shared bike users behavior around rail transit stations,which will contribute to improving the service and efficiency of both rail transit and BSS.展开更多
Improvement on mining the frequently visited groups of web pages was studied. First, in the data preprocessing phrase, we introduce an extra frame filtering step that reduces the negative influence of frame pages on t...Improvement on mining the frequently visited groups of web pages was studied. First, in the data preprocessing phrase, we introduce an extra frame filtering step that reduces the negative influence of frame pages on the result page groups. Through recognizing the frame pages in the site documents and constructing the frame subframe relation set, the subframe pages that influence the final mining result can be efficiently filtered. Second, we enhance the mining algorithm with the consideration of both the site topology and the content of the web pages. By the introduction of the normalized content link ratio of the web page and the group interlink degree of the page group, the enhanced algorithm concentrates more on the content pages that are less interlinked together. The experiments show that the new approach can effectively reveal more interesting page groups, which would not be found without these enhancements.展开更多
The improvement of antibiotic rational use in China was studied by usage analysis of combination antibiotic therapy for type Ⅰ incisions in 244 hospitals. Five kinds of hospitals, including general hospital, maternit...The improvement of antibiotic rational use in China was studied by usage analysis of combination antibiotic therapy for type Ⅰ incisions in 244 hospitals. Five kinds of hospitals, including general hospital, maternity hospital, children's hospital, stomatological hospital and cancer hospital, from 30 provinces were surveyed. A systematic random sampling strategy was employed to select outpatient prescriptions and inpatient cases in 2011 and 2012. A total of 29 280 outpatient prescriptions and 73 200 inpatient cases from 244 hospitals in each year were analyzed. Data were collected with regards to the implementation of the national antibiotic stewardship program(NASP), the overall usage and the prophylactic use of antibiotic for type Ⅰ incisions. Univariate analysis was used for microbiological diagnosis rate before antimicrobial therapy, prophylactic use of antibiotics for typeⅠincision operation, and so on. For multivariate analysis, the use of antibiotics was dichotomized according to the guidelines, and entered as binary values into logistic regression analysis. The results were compared with the corresponding criteria given by the guidelines of this campaign. The antibiotic stewardship in China was effective in that more than 80% of each kind of hospitals achieved the criteria of recommended antibiotics varieties. Hospital type appeared to be a factor statistically associated with stewardship outcome. The prophylactic use of antibiotics on type Ⅰ incision operations decreased by 16.22%(P〈0.05). The usage of combination antibiotic therapy for type Ⅰ incisions was also decreased. Region and bed size were the main determinants on surgical prophylaxis for type Ⅰ incision. This national analysis of hospitals on antibiotic use and stewardship allows relevant comparisons for bench marking. More efforts addressing the root cause of antibiotics abuse would continue to improve the rational use of antibiotics in China.展开更多
基金in part by National Undergraduate Innovation and Entrepreneurship Training Program under Grant No.202310347039Zhejiang Provincial Natural Science Foundation of China under Grant No.LZ22F020002Huzhou Science and Technology Planning Foundation under Grant No.2023GZ04.
文摘The Internet of Things(IoT)has characteristics such as node mobility,node heterogeneity,link heterogeneity,and topology heterogeneity.In the face of the IoT characteristics and the explosive growth of IoT nodes,which brings about large-scale data processing requirements,edge computing architecture has become an emerging network architecture to support IoT applications due to its ability to provide powerful computing capabilities and good service functions.However,the defense mechanism of Edge Computing-enabled IoT Nodes(ECIoTNs)is still weak due to their limited resources,so that they are susceptible to malicious software spread,which can compromise data confidentiality and network service availability.Facing this situation,we put forward an epidemiology-based susceptible-curb-infectious-removed-dead(SCIRD)model.Then,we analyze the dynamics of ECIoTNs with different infection levels under different initial conditions to obtain the dynamic differential equations.Additionally,we establish the presence of equilibrium states in the SCIRD model.Furthermore,we conduct an analysis of the model’s stability and examine the conditions under which malicious software will either spread or disappear within Edge Computing-enabled IoT(ECIoT)networks.Lastly,we validate the efficacy and superiority of the SCIRD model through MATLAB simulations.These research findings offer a theoretical foundation for suppressing the propagation of malicious software in ECIoT networks.The experimental results indicate that the theoretical SCIRD model has instructive significance,deeply revealing the principles of malicious software propagation in ECIoT networks.This study solves a challenging security problem of ECIoT networks by determining the malicious software propagation threshold,which lays the foundation for buildingmore secure and reliable ECIoT networks.
基金funded by National Natural Science Foundation of China(under Grant No.61905201)。
文摘The field of finance heavily relies on cybersecurity to safeguard its systems and clients from harmful software.The identification of malevolent code within financial software is vital for protecting both the financial system and individual clients.Nevertheless,present detection models encounter limitations in their ability to identify malevolent code and its variations,all while encompassing a multitude of parameters.To overcome these obsta-cles,we introduce a lean model for classifying families of malevolent code,formulated on Ghost-DenseNet-SE.This model integrates the Ghost module,DenseNet,and the squeeze-and-excitation(SE)channel domain attention mechanism.It substitutes the standard convolutional layer in DenseNet with the Ghost module,thereby diminishing the model’s size and augmenting recognition speed.Additionally,the channel domain attention mechanism assigns distinctive weights to feature channels,facilitating the extraction of pivotal characteristics of malevolent code and bolstering detection precision.Experimental outcomes on the Malimg dataset indicate that the model attained an accuracy of 99.14%in discerning families of malevolent code,surpassing AlexNet(97.8%)and The visual geometry group network(VGGNet)(96.16%).The proposed model exhibits reduced parameters,leading to decreased model complexity alongside enhanced classification accuracy,rendering it a valuable asset for categorizing malevolent code.
文摘In this editorial,I comment on the article by Zhang et al.To emphasize the importance of the topic,I discuss the relationship between the use of smart medical devices and mental health.Smart medical services have the potential to positively influence mental health by providing monitoring,insights,and inter-ventions.However,they also come with challenges that need to be addressed.Understanding the primary purpose for which individuals use these smart tech-nologies is essential to tailoring them to specific mental health needs and prefe-rences.
基金This work was supported by the National Major Basic Research and Development Program(No.TG1999016004)Jiangsu Provincial Natural Science Foundation(No.BK2003213).
文摘Codon usage is the selective and nonrandom use of synonymous codons to encode amino acids in genes for proteins. The analysis of codon usage may improve the understanding of cocion preferences between different species and allow to rebuild the codons of exogenous genes to increase the expression efficiency of exogenous genes, Here, codon DNA sequence (CDS) of four poplar species, including Populus tremuloides Michx., P. tomentosa Carr., P. deltoides Marsh., and P. trichocarpa Torr. & Gray., is used to analyze the relative frequency of synonymous codon (RFSC). High-frequency codons are selected by high-frequency (HF) codon analysis. The results indicate that the codon usage is common for all four poplar species and the codon preference is quite similar among the four poplar species. However, CCT encoding for Pro, and ACT coding for Thr are the preferred codons in P. tremuloides and P. tomentosa, whereas CCA coding for Pro, and ACA coding for Thr are preferred in P. deltoides and P. trichocarpa The codons such as TGC coding for Cys, TTC coding for Phe, and AAG coding for Lys, are preferred in the poplar species except P trichocarpa. GAG coding for Glu is preferred only in P deltoides, while the other three poplar species prefer to use GAA. The commonness of preferred codon allows exogenous gene designed by the preferred cocion of one of the different poplar species to be used in other poplar species.
文摘Burkholderia mallei is regarded as a potential biological weapon by the Centers for Disease Control and Prevention. In this study, the main factors shaping codon usage in the genome of B. mallei ATCC 23344 were firstly reported. The results showed that the primary trend in codon usage variation in the B. mallei is due to translational selection; while compositional mutation bias is relatively the weaker influence and the hydrophobicity of each protein and gene length are only the minor influences. At the same time, 21 codons defined firstly as 'optimal codons' might provide more useful information for the expression of target genes and development of a vaccine to prevent glanders.
文摘The synonymous codon usage in the translational initiation and termination regions of genes of severe acute respiratory syndrome (SARS) coronavirus and five other viruses in Coronaviridae was systematically analyzed.The results indicate that most minor codons for these coronaviruses are preferentially used in the initial and terminal region.The minor codons preferentially used in the initial region are thought to have a negative effect on gene expression,which can be explained by the minor codon modulator hypothesis.It also indicates that the minor codons preferentially used in the terminal region may regulate the level of gene expression.The proposed results strongly imply that the minor codon modulator hypothesis can be applied to both some bacteria and some viruses.
文摘Based on lawn function theory and urban planning perspectives, functions of urban lawns were analyzed, status and prospect of the multiple usages of lawn were revealed. Urban lawn was concluded as an important part of modern urban greening, moveover, it has been integrated in people's lives gradually by playing a significant role in people's work, studying, leisure, urban disaster prevention and mitigation. At the same time, problems rise from the multiple usages of lawn were discussed and improvement suggestions were put forward.
基金The work is supported by National Natural Science Foundation of China (No. 60121101).
文摘In this study, a comparative analysis of the codon usage bias was performed in Aeropyrum pernix K1 and two other phylogenetically related Crenarchaeota microorganisms (i.e., Pyrobaculum aerophilum str. IM2 and Sulfolobus acidocaldarius DSM 639). The results indicated that the synonymous codon usage in A. pernix K1 was less biased, which was highly correlated with the GC3s value. The codon usage patterns were phylogenetically conserved among these Crenarchaeota microorganisms. Comparatively, it is the species function rather than the gene function that determines their gene codon usage patterns. A. pernix K1, P. aerophilum str. IM2, and S. acidocaldarius DSM 639 live in differently extreme conditions. It is presumed that the hving environment played an important role in determining the codon usage pattern of these microorganisms. Besides, there was no strain-specific codon usage among these microorganisms. The extent of codon bias in A. pernix K1 and S. acidocaldarius DSM 639 were highly correlated with the gene expression level, but no such association was detected in P. aerophilum str. IM2 genomes.
基金supported in part by the Hi-Tech Re-search and Development Program of China ("863" Program) (No. 2007AA02Z329)the National Natural Science Foundation of China (Grant No. 20060213024)
文摘Codon usage in chloroplast genome of six seed plants (Arabidopsis thaliana, Populus alba, Zea mays, Triticum aestivum, Pinus koraiensis and Cycas taitungensis) was analyzed to find general patterns of codon usage in chloroplast genomes of seed plants. The results show that chloroplast genomes of the six seed plants had similar codon usage patterns, with a strong bias towards a high representation of NNA and NNT codons. In chloroplast genomes of the six seed plants, the effective number of codons (ENC) for most genes was similar to that of the expected ENC based on the GC content at the third codon position, but several genes with low ENC values were laying below the expected curve. All of these data indicate that codon usage was dominated by a mutational bias in chloroplast genomes of seed plants and that selection appeared to be limited to a subset of genes and to only subtly affect codon usage. Meantime, four, six, eight, nine, ten and 12 codons were defined as the optimal codons in chloroplast genomes of the six seed plants.
基金supported by the National Natural Science Foundation of China (31401822)
文摘Apple(Malus×domestica) has been proposed as an important woody plant and the major cultivated fruit trees in temperate regions. Apple whole genome sequencing has been completed, which provided an excellent opportunity for genome-wide analysis of the synonymous codon usage patterns. In this study, a multivariate bioinformatics analysis was performed to reveal the characteristics of synonymous codon usage and the main factors affecting codon bias in apple. The neutrality, correspondence, and correlation analyses were performed by Codon W and SPSS(Statistical Product and Service Solutions) programs, indicating that the apple genome codon usage patterns were affected by mutational pressure and selective constraint. Meanwhile, coding sequence length and the hydrophobicity of proteins could also influence the codon usage patterns. In short, codon usage pattern analysis and determination of optimal codons has laid an important theoretical basis for genetic engineering, gene prediction and molecular evolution studies in apple.
基金Supported by Earmarked Fund for China Agriculture Research System(CARS-31-15)Construction of Plateau Discipline of Fujian Province(102/71201801101)
文摘[Objective] The objective of this study was to understand the codon usage bias pattern of banana pathogenesis-related 17 gene, Basic Secretory Protease gene(MaBSP). [Method] Relative codon usage patterns of MaBSP were calculated using the software CodonW version 1.4.2. and the web-based tool(http://kazusa.or.jp/codon/).[Result] Our findings showed that C-ended and G-ended codons were the most preferential except the TER codon UGA which was coded for by just one codon. The ENc value, relationship between AT bias and GC bias, Random synonymous codon usage(RSCU) and CAI all showed that codon bias usage existed in MaBSP gene.[Conclusion] The codon usage patterns of MaBSP gene is principally influenced by natural selection in the third position. However, other multiple factors also influence this pattern.
文摘Codon usage bias(CUB) is a unique property of genome which refers to non-random usage of synonymous codons in coding sequences. The present study makes an attempt to find out the pattern of CUB in chloroplast(cp) genes among three tea species, i.e., Camellia sinensis var. assamica(Assam tea), Camellia sinensis var. sinensis(Chinese tea) and Camellia pubicosta(wild tea species) as no work on CUB was reported earlier. To understand the patterns of codon usage among the cp genes of three tea groups, we used bioinformatic tools to investigate the protein coding sequences of cp genes. In our present study, the mean nucleobase T was the highest whereas C was the lowest in all the three tea groups. The overall AT content was more than GC content, i.e., genes were AT rich. The scaled chi-square(SCS) value indicated that the CUB of cp genes was low. The codon CGT(Arg) was over-represented in C. sinensis var. sinensis whereas GGA(Pro) was over-represented in C. pubicosta species. Heatmap study revealed that most of the GC ending codons showed positive correlations between codon usage and GC3 while AT ending codons exhibited negative correlations. From neutrality plot analysis, it was evident that natural selection had played a major role, while mutation pressure exerted a minor effect in the CUB of cp genes in three tea groups. Highly significant(P<0.01) positive correlation was found between SCS and synonymous codon usage order(SCUO) of cp genes which suggested that high expression of cp genes was associated with high degree of CUB.
基金supported by the National High Tech Development Project of Chinathe 863 Program (Grant Nos.2007AA02Z329)the National Natural Science Foundation of China (Grant Nos.20060213024).
文摘The pattern of codon usage in the chloroplast genome of Populus alba was investigated. Correspondence analysis (a commonly used multivariate statistical approach) and method of effective number of codons (ENc)-plot were conducted to analyze synonymous codon usage. The results of correspondence analysis showed that the distribution of genes on the major axis was significantly correlated with the frequency of use of G+C in synonymously variable third position of sense codon (GC3S), (r=0.349), and the positions of genes on the axis 2 and axis 3 were significantly correlated with CAI (r=-0.348, p〈0.01 and r=0.602, p〈0.01). The ENc for most genes was similar to that for the expected ENc based on the GC3s, but several genes with low ENc values were lying below the expected curve. All of these data indicated that codon usage was dominated by a mutational bias in chloroplast gcnome ofP. alba. The selection in nature for translational efficiency only played a minor role in shaping codon usage in the chloroplast genome ofP alba.
基金Under the auspices of National Natural Science Foundation of China(No.41571146)National Natural Science Youth Foundation of China(No.51708276)Postdoctoral Science Foundation of China(No.2017M611781)
文摘Future or smart community, which mainly refers to the development of community information and communication technology(ICT) platforms or devices, has received considerable attention from urban governments and scholars. However, only a few studies have been conducted to test the actual effects of using these community ICT platforms or devices on the community satisfaction of residents. Therefore, the present study conducts a survey in 40 communities in Nanjing, China and uses a mixed linear regression model to determine the relationship between community ICT usage and community satisfaction. Results indicate that residents with high-level community ICT usage are more satisfied with their community than those with low-level community ICT usage. Moreover, evident differences are observed regarding the influence of new commodity, old commodity and affordable housing communities in Nanjing. These findings are meaningful for the construction and development of future communities.
文摘Species diversity and ethno-medicinal usage of 39 species of invasive plants were explored in and around two protected areas, Khadimnagar National Park (KNP) and Rema-Kalenga Wildlife Sanctu- ary (RKWS), of northeastern Bangladesh,. Status of invasive plants were investigated in 60 sample plots with 5 different habitat types, including forest, roadside, homestead, fallow land and others (ponds, canals, water logged areas, agricultural land, etc.). Data about the usage of invasive plants in traditional health care were collected through interviewing 110 households. Among the five habitat types, fallow land (28 species).possessed the highest number of species, followed by roadside (25 species), forest (23 species), homestead (22 species) and others (13 species). Based on the survey, invasive plants of study areas were also categorized into five degrees of invasiveness e.g., naturalized, introduced, possibly invasive, moderately invasive and highly invasive. Additionally, there is the linear trend between degrees of invasivaness and use percentage of invasive plants. Total 39 species of invasive plants belonging to 29 families were recorded, which are generally used to treat 37 diseases, ranging from simple headache to highly complicated eye and heart diseases. The majority of the species used by the local inhabitants were herbs (16 species), followed by some shrubs (11 species), climbers (5 species), trees (5 species) and grasses (2 species). The use percentage of aboveground plant parts were higher (70.58%) than that of underground plant parts (16.18%).
文摘Spam is no longer just commercial unsolicited email messages that waste our time, it consumes network traffic and mail servers’ storage. Furthermore, spam has become a major component of several attack vectors including attacks such as phishing, cross-site scripting, cross-site request forgery and malware infection. Statistics show that the amount of spam containing malicious contents increased compared to the one advertising legitimate products and services. In this paper, the issue of spam detection is investigated with the aim to develop an efficient method to identify spam email based on the analysis of the content of email messages. We identify a set of features that have a considerable number of malicious related features. Our goal is to study the effect of these features in helping the classical classifiers in identifying spam emails. To make the problem more challenging, we developed spam classification models based on imbalanced data where spam emails form the rare class with only 16.5% of the total emails. Different metrics were utilized in the evaluation of the developed models. Results show noticeable improvement of spam classification models when trained by dataset that includes malicious related features.
基金supported by the National Natural Science Foundation of China (No.30770302 and 30570970)the Program of Ministry of Science and Technology of the Republic of China (No.2006FY110500)partially by the National Science Fund for Fostering Talents in Basic Research (NSFC-J0630964/J0109)
文摘Codon usage bias varies considerably among genomes and even within the genes of the same genome. In eukaryotic organisms, energy production in the form of oxidative phosphorylation (OXPHOS) is the only process under control of both nuclear and mitochondrial genomes. Although factors affecting codon usage in a single genome have been studied, this has not occurred when both interactional genomes are involved. Consequently, we investigated whether or not other factors influence codon usage of coevolved genes. We used Drosophila melanogaster as a model organism. Our χ^2 test on the number of codons of nuclear and mitochondrial genes involved in the OXPHOS system was significantly different (χ^2= 7945.16, P 〈 0.01). A plot of effective number of codons against GC3s content of nuclear genes showed that few genes lie on the expected curve, indicating that codon usage was random. Correspondence analysis indicated a significant correlation between axis 1 and codon adaptation index (R = 0.947, P 〈 0.01) in every nuclear gene sequence. Thus, codon usage bias of nuclear genes appeared to be affected by translational selection. Correlation between axis 1 coordinates and GC content (R = 0.814, P 〈 0.01) indicated that the codon usage of nuclear genes was also affected by GC composition. Analysis of mitochondrial genes did not reveal a significant correlation between axis 1 and any parameter. Statistical analyses indicated that codon usages of both nDNA and mtDNA were subjected to context-dependent mutations.
基金The National Key R&D Program of China(No.2018YFB1600900)the Project of International Cooperation and Exchange of the National Natural Science Foundation of China(No.51561135003)the Key Project of National Natural Science Foundation of China(No.51338003)
文摘In order to study the spatiotemporal characteristics of the dockless bike sharing system(BSS)around urban rail transit stations,new normalized calculation methods are proposed to explore the temporal and spatial usage patterns of the dockless BSS around rail transit stations by using 5-weekday dockless bike sharing trip data in Nanjing,China.First,the rail transit station area(RTSA)is defined by extracting shared bike trips with trip ends falling into the area.Then,the temporal and spatial decomposition methods are developed and two criterions are calculated,namely,normalized dynamic variation of bikes(NDVB)and normalized spatial distribution of trips(NSDT).Furthermore,the temporal and spatial usage patterns are clustered and the corresponding geographical distributions of shared bikes are determined.The results show that four temporal usage patterns and two spatial patterns of dockless BSS are finally identified.Area type(urban center and suburb)has a great influence on temporal usage patterns.Spatial usage patterns are irregular and affected by limited directions,adjacent rail transit stations and street networks.The findings can help form a better understanding of dockless shared bike users behavior around rail transit stations,which will contribute to improving the service and efficiency of both rail transit and BSS.
文摘Improvement on mining the frequently visited groups of web pages was studied. First, in the data preprocessing phrase, we introduce an extra frame filtering step that reduces the negative influence of frame pages on the result page groups. Through recognizing the frame pages in the site documents and constructing the frame subframe relation set, the subframe pages that influence the final mining result can be efficiently filtered. Second, we enhance the mining algorithm with the consideration of both the site topology and the content of the web pages. By the introduction of the normalized content link ratio of the web page and the group interlink degree of the page group, the enhanced algorithm concentrates more on the content pages that are less interlinked together. The experiments show that the new approach can effectively reveal more interesting page groups, which would not be found without these enhancements.
基金supported by the Major Program of National Fund of Philosophy and Social Science of China(No.15ZDC037)
文摘The improvement of antibiotic rational use in China was studied by usage analysis of combination antibiotic therapy for type Ⅰ incisions in 244 hospitals. Five kinds of hospitals, including general hospital, maternity hospital, children's hospital, stomatological hospital and cancer hospital, from 30 provinces were surveyed. A systematic random sampling strategy was employed to select outpatient prescriptions and inpatient cases in 2011 and 2012. A total of 29 280 outpatient prescriptions and 73 200 inpatient cases from 244 hospitals in each year were analyzed. Data were collected with regards to the implementation of the national antibiotic stewardship program(NASP), the overall usage and the prophylactic use of antibiotic for type Ⅰ incisions. Univariate analysis was used for microbiological diagnosis rate before antimicrobial therapy, prophylactic use of antibiotics for typeⅠincision operation, and so on. For multivariate analysis, the use of antibiotics was dichotomized according to the guidelines, and entered as binary values into logistic regression analysis. The results were compared with the corresponding criteria given by the guidelines of this campaign. The antibiotic stewardship in China was effective in that more than 80% of each kind of hospitals achieved the criteria of recommended antibiotics varieties. Hospital type appeared to be a factor statistically associated with stewardship outcome. The prophylactic use of antibiotics on type Ⅰ incision operations decreased by 16.22%(P〈0.05). The usage of combination antibiotic therapy for type Ⅰ incisions was also decreased. Region and bed size were the main determinants on surgical prophylaxis for type Ⅰ incision. This national analysis of hospitals on antibiotic use and stewardship allows relevant comparisons for bench marking. More efforts addressing the root cause of antibiotics abuse would continue to improve the rational use of antibiotics in China.