Objective:To explore the differences of CBCT image gray value of commonly used dental materials.Methods:CBCT was used to scan 36 kinds of commonly dental material blocks,the tomographic image gray value was measured by Mimics software.Re-sults:CBCT image gray values of the materials were obtained.There were differences of the gray values of the materials not only among the different types,but also among the different varieties of the same materials.Conclusion:The discipline of CBCT image gray value differences of commonly used dental materials provided an objective basis for the establishment of 3D digital model including dental ma-terials.

Objective To sequence and analyze the complete nucleotide sequence of the mitochondrial genome of Oncomelania hupensis. Methods Four long fragments were amplified by long PCR using the primers designed based on mtDNA-COⅠ, Cytb, 16S rRNA and COⅢ gene sequences, and sequenced by conserved primer-walking. Rusults The mitochondrial genome (GenBank accession no. FJ997214) was a circular molecule of 15 182 bp with a total A+T content of 67.32%, and contained 13 protein-coding genes, 2 ribosomal RNA genes, 22 tRNA genes, and an A+T-rich region of 72 bp. All 13 protein-coding genes of the O. hupensis mtDNA used ATG as start codon. Canonical TAA and TAG termination codons were found in 12 protein-coding genes, and the remaining one (ND1) had an incomplete termination codon (T). Two short gene overlaps were found with a length of 4 bp and 7 bp, respectively. The length of 21 total intergenic region of mtDNA was 145 bp ranging from 1-30 bp. A total of 22 transferring RNA were found, all of which were typical cloverleaf structure except for two tRNASer, one tRNAGln and one tRNAIle. Conclusion The complete sequence of O. hupensis mitochondrial genome has been determined.

Objective To explore that whether the normoxic low altitude measurement of arterial blood pressure would predict subsequent susceptibility to acute mountain sickness ( AMS) during rapid ascent to high altitude .Methods Arterial blood pressure ( using a wrist sphygmomanometer ) was determined in two hundred and four healthy lowlanders first exposed to 3700 m-altitude (Lhasa) from plain (500 m) by air, and the Lake Louise self-report questionnaire(LLS) was used to assess AMS.We compared the low altitude blood pressure related indicators of two groups ( AMS and non-AMS ) and analyzed the relationship of diagnostic score and blood pressure related indicators .Results ①The incidence of AMS in the selected subjects was 53.92% by LLS.AMS scores increased markedly at high-altitude (P<0.05 versus low altitude).②Diastolic blood pressure (DBP) and mean arterial BP (MABP) in the AMS group were higher than those in the non-AMS group(P<0.05).The low altitude DBP levels for diagnosis of AMS at high-altitude (3700 m) had an area under curve(AUC) =0.598, P<0.05, with sensitivity of 56.3%, specificity of 63.2%, and cut-off point of 72.5 mmHg. Conclusion ①After acute exposure to high altitude , the incidence of AMS increases significantly .②A higher baseline DBP may be considered a potential risk factor for AMS , and is positively associated with LLS .DBP may serve as a predic-tive parameter for diagnosis of AMS .However , the clinical application of DBP as a predictive criterion is limited because of its poor specificity or sensitivity .The use of DBP as a predictive criterion should be combined with other indicators for the better predictive value of AMS .

Accurate segmentation of oral surgery-related tissues from cone beam computed tomography(CBCT)images can significantly accelerate treatment planning and improve surgical accuracy.In this paper,we propose a fully automated tissue segmentation system for dental implant surgery.Specifically,we propose an image preprocessing method based on data distribution histograms,which can adaptively process CBCT images with different parameters.Based on this,we use the bone segmentation network to obtain the segmentation results of alveolar bone,teeth,and maxillary sinus.We use the tooth and mandibular regions as the ROI regions of tooth segmentation and mandibular nerve tube segmentation to achieve the corresponding tasks.The tooth segmentation results can obtain the order information of the dentition.The corresponding experimental results show that our method can achieve higher segmentation accuracy and efficiency compared to existing methods.Its average Dice scores on the tooth,alveolar bone,maxillary sinus,and mandibular canal segmentation tasks were 96.5%,95.4%,93.6%,and 94.8%,respectively.These results demonstrate that it can accelerate the development of digital dentistry.

The use of robots to augment human capabilities and assist in work has long been an aspiration.Robotics has been developing since the 1960s when the first industrial robot was introduced.As technology has advanced,robotic-assisted surgery has shown numerous advantages,including more precision,efficiency,minimal invasiveness,and safety than is possible with conventional techniques,which are research hotspots and cutting-edge trends.This article reviewed the history of medical robot development and seminal research papers about current research progress.Taking the autonomous dental implant robotic system as an example,the advantages and prospects of medical robotic systems would be discussed which would provide a reference for future research.

Objective To isolate the microsatellite DNA sequences of Oncomelania hupensis and analyze the polymorphic microsatellite loci.Methods The digested genomic fragments were hybridized with biotinylated oligonucleotide probes.The target fragments moleculars were captured and enriched.Then these fragments were cloned and sequenced.The suitable microsatellite loci were chosen and the polymorphism was screened by PAGE gel electrophoresis.Results A total of 205 microsateilite DNA sequences were obtained (GenBank accession numbers :GU204044～GU204248).The percentage of perfect microsatellite DNA sequence was 36.10% (74/205),with imperfect sequence as 49.76% (102/205) and compound sequence as 14.15% (29/205).Twenty typical microsatellite sequences were selected to design amplifying primers,and 13 microsatellite loci were found to be polymorphism.Conclusion A total of 205 microsatellite DNA sequences of Oncomelania hupensis are isolated and first reported,which will be useful for population genetic and mapping studies of Oncomelania hupensis.

China's prevention and control of parasitic diseases has made remarkable achievements. However,the prevalence and transmission of parasitic diseases is impacted by the complicated natural and social factors of environment ,natural disas-ters,population movements,and so on. Therefore,there are still the risks of the outbreak of emergency parasitic diseases af-fairs,which may affect the control effectiveness of parasitic diseases and endanger the social stability seriously. In this article , we aim at the analysis of typical cases of emergency parasitic disease affairs and their impacts on public health security in China in recently years,and we also elaborate the disposal characteristics of emergency parasitic disease affairs,and propose the estab-lishment of response system to emergency parasitic disease affairs in China,including the organizational structure and response flow path,and in addition,point out that,in the future,we should strengthen the system construction and measures of the re-sponse system to emergency parasitic disease affairs,so as to control the risk and harm of parasitic disease spread as much as possible and to realize the early intervention and proper disposal of emergency parasitic disease affairs.

With the growth of the global economy , changes in climate and ecological environments, and increased mobility of humans and animals, the transmission risk of vector-borne tropical diseases continues to rise. To address this challenge, strengthening surveillance of vector-borne tropical diseases is urgent. This consensus brought together 29 renowned experts in related professional fields from 26 institutions in China, who, through analyzing the epidemic trend and hazard situation of vector-borne tropical diseases and summarizing the working experiences of experts, have firstly reached following consensus: the burden of vector-borne tropical diseases is heavy with great threats to human health; China has achieved remarkable results in prevention and control of vector-borne tropical diseases , but still needs to strengthen the surveillance and response actively. Secondly, a unanimous consensus has been reached on the aspects of surveillance definition, objectives, contents, and methods of vector-borne tropical diseases. Thirdly, detail requirements have been agreed including: strengthening the concept of early surveillance and forecast, standarding the function, evaluation steps, and construction requirements of surveillance system for vector-borne tropical diseases. Fourthly, key tasks were put forward that need to be investigated and strengthened in the future. This expert consensus provides a standardized reference for the construction of the surveillance pathway and surveillance system for vector-borne tropical diseases in China.

Objective To understand the spatial distribution characteristics of wild feces in schistosomiasis endemic areas of Jiangling County,Hubei Province and further explore the source of infection efficiently,so as to provide the evidence for the development of corresponding monitoring and response technology. Methods In 2011,the fresh wild feces were investigated every two months in the selected 15 villages by the severity of historical endemic in Jiangling County. The schistosome miracidi-um hatching method was used to test the schistosome infection of the wild feces. The descriptive analysis and spatial analysis were used for the description of the spatial distribution of the wild feces. Results Totally 701 wild feces samples were collected with the average density of 0.0556/100 m2,and the positive rate of the wild feces was 11.70%(82/701). The results of the re-gression analysis showed a positive spatial correlation between the positive rate of wild feces and the rate of human infection,the area with infected Oncomelania hupensis and the number of fenced cattle,and the corrected R2 of the model was 0.58. Conclu-sion The infection rate of wild feces is positively correlated with the rate of human infection,area with infected O. hupensis and number of fenced cattle in space in Jiangling County,so the prevention and control measures could be conducted according to the spatial distribution of the positive wild feces.

Objective To evaluate the schistosomiasis control effect of the measures of replacing cattle with machine for cul?tivation and forbidding depasturage of livestock on marshlands in marshland and lake regions. Methods The retrospective re?view and field survey were implemented in the Jiangling and Gongan counties of Hubei Province where were implemented with the measure of replacing cattle with machine for cultivation,and Yuanjiang and Huarong counties of Hunan Province where were implemented with the measure of forbidding the depasturage of livestock on marshlands. The schistosome infection status of hu?man,cattle,and Oncomelania hupensis snails,and schistosome?infested field excreta were surveyed from 2007 to 2013. The ef?fects of the interventions were compared before and after their implementations. Results The 6 villages of Hubei Province were implemented with the measure of replacing cattle with machine for cultivation,and 7 villages of Hunan Province were imple? mented with the measure of forbidding the depasturage of livestock on marshlands. From 2007 to 2013,the schistosome infection rates of residents declined from 3.95%to 0.70%(χ2 =128.376,P<0.05),with the descend range of 82.53%. The descend ranges of the measures of replacing cattle with machine for cultivation and forbidding the depasturage of livestock on marshlands were 83.081%and 81.62%respectively,and there was no significant difference between the two measures(χ2 =0.132,P>0.05). The infection rate of cattle decreased from 3.66%in 2007 to 0.65%in 2013,and the descend range was 82.24%(χ2=13.692,P<0.05). The field excreta was surveyed in the snail breeding place in 2013. The investigated area was 157.435 hm2, and 625 samples of field feces of cattle were collected with the density of field excreta of 3.97/hm2,and the positive rate was 1.12%(7/625). The schistosome infection rate of snails and the density of infected snails decreased successively from 2007, and no infected snails were detected from 2011 to 2013. Conclusions The schistosomiasis endemic situation are decreased sig?nificantly after the interventions of replacing cattle with machine for cultivation and forbidding the depasturage of livestock on marshlands. Therefore,schistosomiasis control effect of these measures is notable in the marshland and lake regions.