边缘计算能力运营模式初探

边缘计算是云计算的特殊形式,其分散的网络架构,将应用、数据与服务移到了网络的边缘节点,致力于解决时延长、汇聚量大而出现的请求滞后问题。随着5G商用,工业控制、车联网等行业将全面发展,对边缘计算能力的需求更加迫切。纵观行业要求及运营商的MEC布局,急需加速推进边缘云的运营模式的研究工作。

Mesozoic Tectonothermal Evolution of the Southern Central Asian Orogenic Belt: Evidence from Apatite Fission-Track Thermochronology in Shalazha Mountain, Inner Mongolia

Mesozoic intracontinental orogeny and deformation were widespread within the southern Central Asian Orogenic Belt(CAOB). Chronological constraints remain unclear when assessing the Mesozoic evolution of the central segment of this region. The tectonic belt of Shalazha Mountain located in the center of this region is an ideal place to decode the deformation process. Apatite fission-track(AFT) thermochronology in Shalazha Mountain is applied to constrain the Mesozoic tectonothermal evolution of the central segment of southern CAOB. The bedrock AFT ages range from 161.8 ± 6.9 to 137.0 ± 7.3 Ma, and the first reported detrital AFT obtained from Lower Cretaceous strata shows three age peaks: P1(ca. 178 Ma), P2(ca. 149 Ma) and P3(ca. 105.6 Ma). Bedrock thermal history modeling indicates that Shalazha Mountain have experienced three stages of differential cooling: Late Triassic–Early Jurassic(~230–174 Ma), Late Jurassic–Earliest Cretaceous(~174–135 Ma) and later(~135 Ma). The first two cooling stages are well preserved by the detrital AFT thermochronological result(P1, P2) from the adjacent Lower Cretaceous strata, while P3(ca. 105.6 Ma) records coeval volcanic activity. Furthermore, our data uncover that hanging wall samples cooled faster between the Late Triassic and the Early Cretaceous than those from the footwall of Shalazha thrust fault, which synchronizes with the cooling of the Shalazha Mountain and implies significant two-stage thrust fault activation between ca. 230 and 135 Ma. These new low-temperature thermochronological results from the Shalazha Mountain region and nearby reveal three main phases of differential tectonothermal events representing the Mesozoic reactivation of the central segment of the southern CAOB. In our interpretations, the initial rapid uplift in the Late Triassic was possibly associated with intracontinental orogenesis of the CAOB. Subsequent Middle Jurassic–Earliest Cretaceous cooling is highly consistent with the Mesozoic intense intraplate compression that occurred in the southern CAOB, and is interpreted as a record of closure of the Mongol-Okhotsk Ocean. Then widespread Cretaceous denudation and burial in the adjacent fault basin could be linked with the oblique subduction of the Izanagi Plate along the eastern Eurasian Plate, creating a northeast-trending normal fault and synchronous extension. However, our AFT thermochronometry detects no intense Cenozoic reactivation information of Shalazha Mountain region.

Genetic structure of Aedes albopictus(Diptera:Culicidae)populations in China and relationship with the knockdown resistance mutations

Background Mosquito control is needed to prevent dengue fever, which is mainly spread byAedes albopictus in China. Application of insecticides is one of the main mosquito control methods;however, this approach can fail due to the knockdown resistance (kdr) gene mutation that causes decreased sensitivity to insecticides inAe. albopictus. Thekdr mutation patterns among different regions in China differ significantly. However, the underlying mechanism and factors that influencekdr mutation remain unclear. To explore the potential influence of genetic background on the development of insecticide resistance inAe. albopictus, we analyzed the genetic structure ofAe. albopictus populations in China and its correlation with majorkdr mutations.Methods We collectedAe. albopictus from 17 sites in 11 provinces (municipalities) across China from 2016 to 2021 and extracted the genomic DNA from individual adult mosquitoes. We selected eight microsatellite loci for genotyping, and based on microsatellite scores, we estimated intraspecific genetic diversity, population structure, and effective population size. The association between the intrapopulation genetic variation and F1534 mutation rate was evaluated by the Pearson correlation coefficient.Results Based on variation analysis of the microsatellite loci of 453 mosquitoes representing 17 populations throughout China, more than 90% of the variation occurred within individuals, whereas only about 9% of the variation occurred among populations, indicating that field populations ofAe. albopictus are highly polymorphic. The northern populations tended to belong to gene pool I (BJFT 60.4%, SXXA 58.4%, SDJN 56.1%, SXYC 46.8%), the eastern populations tended to belong to pool III (SH 49.5%, JZHZ 48.1%), and the southern populations tended to belong to three different gene pools. Moreover, we observed that the greater the fixation index (FST), the lower the wild-type frequency of F1534 ofVSGC.Conclusions The degree of genetic differentiation amongAe. albopictus populations in China was low. These populations were divided into three gene pools, in which the northern and eastern pools are relatively homogeneous, while the southern gene pool is heterogeneous. The possible correlation between its genetic variations andkdr mutations is also noteworthy.

Development of Fenghuang Dancong Tea and Chestnut Sauce

To produce Fenghuang Dancong tea and chestnut sauce that is more in line with people s health needs and has better flavor,the dosage of tea,tea powder,white sugar and milk was analyzed,and the optimal formula of Fenghuang Dancong tea and chestnut sauce was studied through a single factor experiment and orthogonal experiment.The results showed that the best formula of Fenghuang Dancong tea and chestnut sauce was composed of 4.5 g of tea,1.5 g of tea powder,60 g of milk and 5 g of white sugar.The Fenghuang Dancong tea and chestnut sauce made under these conditions was light brown,and had suitable viscosity,delicate and rich taste.It had the fragrance of Fenghuang Dancong tea and the sweet aroma of chestnuts.

肠道微生物对肿瘤发生发展及化疗药物的影响

肠道微生物群在多种肿瘤发生发展过程中的作用引起了人们的广泛关注,近几年大量研究表明微生物群与肿瘤之间有着密切的关系。它们不仅可以与宿主共代谢,对肿瘤治疗产生正面或负面影响,还可以直接促进或消除化疗药物的疗效并介导药物的毒性,从而干预肿瘤的治疗。此外,肠道微生物能够介导免疫疗法,增强患者对肿瘤的免疫应答能力。在此综述中,我们概述了肠道微生物在肿瘤治疗中的意义,揭示其对化疗药物及免疫疗法的影响,并总结多种治疗肿瘤的潜在机制。不仅展现了肠道微生物研究对临床治疗肿瘤的意义,也为临床协助肿瘤治疗提供更多的思路。

Correlation between adult pyrethroid resistance and knockdown resistance(kdr)mutations in Aedes albopictus(Diptera:Culicidae)field populations in China

Background:Arboviral disease transmitted by Aedes albopictus such as dengue fever is an important threat to human health.Pyrethroid resistance raises a great challenge for mosquito control.A systematic assessment of Ae.albopictus resistance status in China is urgently needed,and the study of correlation between pyrethroid resistance and knockdown resistance(kdr)mutations would provide information to guide the control of the Ae.albopictus vector.Methods:Five field populations of Ae.albopictus were collected from Jinan(JN),Hangzhou(HZ),Baoshan(BS),Yangpu(YP)and Haikou(HK),China in 2017.Insecticide-impregnated papers were prepared with four pyrethroid chemicals,deltamethrin,permethrin,beta-cypermethrin and lambda-cyhalothrin.The susceptibility of Ae.albopictus to pyrethroids was tested by the WHO tube assay.Kdr mutations were identified by PCR and sequencing.Moreover,the correlation analysis between kdr alleles and pyrethroid resistance was performed.Results:All five populations of Ae.albopictus showed resistance to four pyrethroid insecticides.One kdr mutant allele at codon 1532 and three at 1534 were detected with frequency of 5.33%(I1532T),44.20%(F1534S),1.83%(F1534 L)and 0.87%(F1534C),respectively.Both 1532 and 1534 mutation mosquitoes were found in the BS and YP populations.Allele I1532T was negatively correlated with deltamethrin resistance phenotype(OR<1),while F1534S mutation was positively correlated with deltamethrin and permethrin resistance(OR>1).Conclusions:The five field populations of Ae.albopictus adults were all resistant to deltamethrin,permethrin,betacypermethrin and lambda-cyhalothrin.Mutant F1534S was clearly associated with pyrethroid resistance phenotype in Ae.albopictus and this could be developed as a molecular marker to monitor the pyrethroid resistance problem in China.

Variable Selection for Fixed Effects Varying Coefficient Models

We consider the problem of variable selection for the fixed effects varying coefficient models. A variable selection procedure is developed using basis function approximations and group nonconcave penalized functions, and the fixed effects are removed using the proper weight matrices. The proposed procedure simultaneously removes the fixed individual effects, selects the significant variables and estimates the nonzero coefficient functions. With appropriate selection of the tuning parameters, an asymptotic theory for the resulting estimates is established under suitable conditions. Simulation studies are carried out to assess the performance of our proposed method, and a real data set is analyzed for further illustration.

Sequencing and analysis of the complete mitochondrial genome in Anopheles sinensis(Diptera:Culicidae)

Background:Anopheles sinensis(Diptera:Culicidae)is a primary vector of Plasmodium vivax and Brugia malayi in most regions of China.In addition,its phylogenetic relationship with the cryptic species of the Hyrcanus Group is complex and remains unresolved.Mitochondrial genome sequences are widely used as molecular markers for phylogenetic studies of mosquito species complexes,of which mitochondrial genome data of An.sinensis is not available.Methods:An.sinensis samples was collected from Shandong,China,and identified by molecular marker.Genomic DNA was extracted,followed by the Illumina sequencing.Two complete mitochondrial genomes were assembled and annotated using the mitochondrial genome of An.gambiae as reference.The mitochondrial genomes sequences of the 28 known Anopheles species were aligned and reconstructed phylogenetic tree by Maximum Likelihood(ML)method.Findings:The length of complete mitochondrial genomes of An.sinensis was 15,076 bp and 15,138 bp,consisting of 13 protein-coding genes,22 transfer RNA(tRNA)genes,2 ribosomal RNA(rRNA)genes,and an AT-rich control region.As in other insects,most mitochondrial genes are encoded on the J strand,except for ND5,ND4,ND4L,ND1,two rRNA and eight tRNA genes,which are encoded on the N strand.The bootstrap value was set as 1000 in ML analyses.The topologies restored phylogenetic affinity within subfamily Anophelinae.The ML tree showed four major clades,corresponding to the subgenera Cellia,Anopheles,Nyssorhynchus and Kerteszia of the genus Anopheles.Conclusions:The complete mitochondrial genomes of An.sinensis were obtained.The number,order and transcription direction of An.sinensis mitochondrial genes were the same as in other species of family Culicidae.

Phylogeny of certain members of Hyrcanus group(Diptera:Culicidae)in China based on mitochondrial genome fragments

Background:Species of the A nopheles hyrcanus group are widely distributed in Palearctic and Oriental regions and some of them are important malaria vectors.The cryptic species of An.hyrcanus group was almost impossible to identify based only on their morphology.The phylogenetic relationship of An.hyrcanus group was also not clear.Methods:Five members of An.hyrcanus group were identified by rDNA ITS2 sequencing as An.yatsushiroensis,An.belenrae,An.kleini,An.lesteri and An.sineroides.The mitochondrial genome fragments were sequenced and annotated using the mitochondrial genome of An.sinensis as reference.Based on the four segments and Joint Data sequences of these species,and other four anopheline species downloaded from GenBank,intraspecific as well as interspecific genetic distances were calculated and the phylogenetic trees were reconstructed by the methods of neighbor joining,maximum parsimony,minimum evolution and maximum likelihood.Findings:Four parts of mitochondrial genomes,which were partial fragments COI+tRNA+COII(F5),ATP6+CO///(F7+F8),A/D7(F19)and IrRNA(F21),were obtained.All fragments were connected as one sequence(referred as Joint Data),which had a total length of 3393 bp.All fragment sequences were highly conservative within species,with the maximum p distance(0.026)calculated by F19 of An.belenroe.The pairwise interspecific p distance calculated by each fragment showed minor or even no difference among An.sinensis,An.kleini and An.belenrae.However,interspecific p distances calculated by the Joint Data sequence ranged from 0.004 (An.belenrae vs An.kleini)to 0.089(An.sineroides vs An.minimus),and the p distances of the six members o f An.hyrcanus group were all less than 0.029.The phylogenetic tree showed two major clades:all subgenus A nopheles species(including six members of An.hyrcanus group,An.otroparvus and An.quadrim aculatus A)and subgenus Cellia(including An.dirus and An.minimus).The An.hyrcanus group was divided into two clusters as{(An.lesteri,An.sineroides)An.yatsushiroensis)and({An.belenrae,An.sinensis)An.kleini)).Conclusions:The An.hyrcanus group in this study could be divided into two clusters,in one of which An.belenrae,An.sinensis and An.kleini were most closely related.More molecular markers would make greater contribution to phylogenetic analysis.

Leishmania infection and blood sources analysis in Phlebotomus chinensis (Diptera:Psychodidae) along extension region of the loess plateau, China

Background:Visceral leishmaniasis(VL)was one of the most important parasitic diseases in China,caused by Leishmania protozoans and transmitted by sand flies.Recently VL cases have reappeared in China,including the extension region of the Loess Plateau.The purpose of this study was to collect fundamental data on the host-vector VL system in the Loess Plateau to assist in the development of prevention and control measures.Methods:Sand flies were collected by light traps from rural areas in Shanxian,Henan,China in 2015,as well as in Wuxiang and Yangquan,Shanxi,China in 2017.The blood sources of sand flies were analyzed by PCR detecting the host-specific mitochondrial cytochrome b(mtDNA cyt b)gene fragments.Leishmania infection in sand flies was detected by amplifying and sequencing ribosomal DNA internal transcribed spacer 1(ITS1).The Leishmania specific antibodies in the sera of local dogs were detected by ELISA kit.Results:Blood sources showed diversity in the extension region of the Loess Plateau,including human,chicken,dog,cattle,pig and goat.Multiple blood sources within a sand fly were observed in samples from Yangquan(17/118,14.4%)and Wuxiang(12/108,11.1%).Leishmania DNA was detected in sand flies collected from Yangquan with minimum infection rate of 1.00%.The ITS1 sequences were conserved with the Leishmania donowni complex.The positive rate of Leishmania specific antibodies in dogs was 5.97%.Conclusions:This study detected the blood sources and Leishmania parasites infection of sand flies by molecular methods in the extension region of Loess Plateau,China.A high epidemic risk of leishmaniasis is currently indicated by the results as the infection of Leishmania in sand flies,the extensive blood sources of sand flies including humans,and positive antibody of Leishmania in local dog sera.Given the recent increase of VL cases,asymptomatic patients,dogs and other potential infected animals should be screened and treated.Furthermore,the density of sand flies needs to be controlled and personal protection should be strengthened.