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【Objective】To improve the linear fit between the reflected spectral center wavelength and external environmental variables in Fiber Bragg Grating (FBG) sensing system, this paper proposes to use particle swarm optimization of Gaussian process regression model to the field of FBG stress sensing.【Methods】For the reflectance spectral characteristics of the FBG, the paper studies the impact of the linear fit in the spectral fitting of FBG sensing system. The particle swarm algorithm is used to search for the optimal hyperparameters in the Gaussian process regression model in order to enhance the predictive performance of the reflectance spectral wavelength of the center. A FBG stress sensing experimental platform was built, and the FBG was laid on the strength beam. Different weights were applied to one end of the equal strength beam to produce axial strain on the FBG, and the reflectance spectral data were collected by the spectrometer and analyzed by linear fitting with the studied model. The results obtained by the unoptimized Gaussian process regression model, the maximum value method, the Gaussian fitting method, and the center of mass method were used as the control group.【Results】The results show that under the conditions of erbium-doped fiber amplifier output power of 10 dBm, transmission fiber distance of 50 m, and the number of sampling points of the spectrometer of 501, the linear fit between the reflected spectral center wavelength and the mass of the weights is better than that of the control group. The linear fit of the studied model can reach up to 0.951 9, which is improved compared with that of the control group. Under the conditions of 501, 251, 167 and 126 spectral sampling points, the studied model can improve the linear fit of the system to 0.990 0, which is a maximum improvement of 0.258 7 compared with the maximum value method.【Conclusion】The analysis results show that the Gaussian process regression model optimized by the particle swarm is able to effectively improve the linear fit of the FBG stress sensing system.

With the rapid development of low-temperature fields such as deep space exploration，polar scientific research，low-temperature storage and transportation，the service conditions for low-temperature structural components are becoming increasingly stringent. Therefore，low-temperature materials have gradually become a research hotspot in the world. This article mainly summarizes the low-temperature performance and related mechanisms of common structural materials such as low-temperature steel，aluminum alloy，titanium alloy，aluminum matrix composites and resin matrix composites. The effects of different crystal structures，alloy types，alloying elements and other factors on the mechanical properties of structural materials such as low temperature strength，plasticity and toughness，and the mechanism of low temperature deformation，strengthening and toughening are concluded. The application and prospect of different grades of low-temperature structural materials in different fields at home and abroad are also briefly introduced. The future research prospect of low-temperature materials is put forward.

The first mining of nearly whole rock lower protective layer working face in Pingdingshan coal mining area is used to liberate the Ji group coal resources of its upper threatened by the gas outburst. The mining of the rock layer at a depth of nearly 1000 meters is bound to increase the depth of the floor damage. Once the L5 weak water-rich aquifer in the aquifuge is disturbed, the indirect recharge channel of the cold ash water is formed, which affects the safety and stability of the rock floor. Firstly, the theoretical model of plastic slip line of double-layer structure floor is established, and the analytical solution of maximum failure depth of double-layer floor under three working conditions is derived. Then through the self-designed similar simulation experimental platform of pore water pressure (spring) and stratum effective stress (jack), the deformation form and failure characteristics of stope roof and floor are simulated and analyzed based on digital image correlation technology. Finally, the borehole strain measurement method was used to carry out on-site monitoring of floor fracture development morphology in Ji15-31040 nearly whole rock working face of Pingdingshan No.12 Coal Mine. The results show that the maximum failure depth of Ji15-31040 nearly whole rock working face floor is 16.59 m by using the plastic slip line theory of double-layer structure floor. The similar simulation experiment reveals that the floor failure is concentrated at both ends of the open-off cut and the working face, with obvious lagging failure characteristics. The maximum failure depth is 17.8 m. After the working face advances 159.9 m into full mining, the floor stress gradually recovers. The field measurement results show that the floor rock mass has a compression-shear slip failure at 7.9 m in front of the working face. The floor before and after the working face is pushed through the borehole shows compression-shear and tension-shear failure, respectively. The maximum failure depth of the floor is between 16.5 m and 18 m. The results of field measurement are in good agreement with theoretical calculation and similar simulation test.

The skeletal system of fish consists of the axial skeleton (skull, vertebral column, ribs, and intermuscular bones) and the appendicular skeleton, which are essential for behavioral and physiological functions such as locomotion, feeding, predator avoidance, and load-bearing. As for the vertebral column of teleosts, it is composed of many vertebrae connected from the head to the caudal base. The morphological characteristics of the vertebrae (such as the number and structure) vary among different fish species. These characters (especially the vertebrae number) provide an important basis for species identification. For instance, the number of vertebrae in Salmo salar is 57–60 (30 trunk vertebrae, 27–30 caudal vertebrae), while rainbow trout (Oncorhynchus mykiss) has a total of 63 vertebrae (including 33 trunk vertebrae and 30 caudal vertebrae), which can be used for species identification. Fish with a similar number of vertebrae require further skeletal morphological features to distinguish them. For instance, the three-dimensional structure of the same vertebra segment from 32 different teleost species (belonging to 10 different orders) were compared and analyzed using Micro-computed tomography (Micro-CT) scanning technology. The results showed that the lamellar trabeculae and its internal cavity structure on the spine differed between the species, suggesting that these structural characteristics can serve as additional evidence to classify and identify fish species. In addition, calcium (Ca) and phosphorus (P) are the most important mineral elements in a fish skeleton, and their contents vary among different fish. Therefore, there is potential to use the skeletal Ca and P contents in classifying and identifying fish and their life history characteristics.To examine the vertebrae number in O. mykiss, specimens of juvenile O. mykiss of body weight (1.27±0.21) g were cleaned and double-stained to obtain the whole skeletal image. A total of 63 vertebrae were identified, and all were completely ossified at this developmental stage. X-ray scanner technology scanned and photographed the entire skeletal structure of adult O. mykiss. The adult results were similar to the juvenile results of 63 vertebrae with both ends connected with the head or tail, and the ribs were attached to the trunk vertebrae. The ventral sides of the 1–33 trunk vertebrae were arranged in an arc, which was downward and separate. No intermuscular spine was evident. On the dorsal side of the vertebrae, the neural arches surrounding the neural canal were fused with the neural spines. Unlike the ribs, the caudal vertebrae had vascular arches, which formed passages for blood vessels and nerves and were fused with the vascular spines on the ventral side.The calcium and phosphorus content, and microstructure of the vertebrae in O. mykiss at different developmental stages were assessed. Vertebrae samples were collected at four developmental stages (young stage Ⅰ, young stage Ⅱ, adult stage Ⅰ, and adult stage Ⅱ; with an average body weight of 4, 35, 644 and 2 129 g, respectively). The calcium and phosphorus contents in the 1–6th vertebrae were assessed by inductively coupled plasma mass spectrometry (ICP-MS). The 4–6th vertebrae were scanned using Micro-CT technology. The results revealed the calcium and phosphorus contents of the vertebrae initially increased and then decreased during development. The highest levels of calcium and phosphorus in the vertebrae was at young stage Ⅱ, (4 711.121±567.948) and (3 649.488±446.961) μmol/g, respectively. The Ca/P molar mass ratio increased significantly with the growth of O. mykiss (P < 0.05). These results indicated that the degree of mineralization in the vertebrae increased with growth and development. Micro-CT scanning results indicated that the bone volume and surface of the vertebrae increased significantly with the growth of O. mykiss. The vertebrae segments became more obvious, and the structure became more complete. The vertebral microstructure indexes in O. mykiss at the different developmental stages suggested the trabecular number (Tb.N) significantly decreased with the growth of O. mykiss (P < 0.05). The highest levels occurred at young stage Ⅰ with (19.915±0.758) ind./mm, the lowest levels occurred at adult stage Ⅱ with (1.960±0.043) ind./mm. The trabecular thickness (Tb.Th) and trabecular separation/spacing (Tb.Sp), both significantly increased with O. mykiss growth (P < 0.05). Tb.Th and Tb.Sp of the vertebrae in O. mykiss were the lowest, (0.060±0.001) mm and (0.068±0.004) mm, respectively at young stage Ⅰ, and the highest levels, (0.718±0.026) mm and (0.402±0.029) mm, respectively) were at adult stage Ⅱ. In addition, the bone volume fraction (BV/TV), tissue mineral density (TMD), and bone mineral density (BMD) showed a trend of initially decreasing and then increasing. The lowest levels were at adult stage Ⅰ, (62.620±13.223)%, (460.300±102.825) mg/mL and (678.052± 4.417) mg/mL, respectively, and the highest BV/TV and TMD, (86.473±1.029)% and (654.797± 7.031) mg/mL were at adult stage Ⅱ. Conversely, the highest BMD, (820.527±5.003) mg/mL, was at young stage Ⅰ. The evaluation indexes of the bone spatial morphological structures (such as TV, BV, BV/TV, BS, Tb.Th, and Tb.Sp) increased significantly during the growth and development of rainbow trout, while Tb.N decreased significantly. The bone strength evaluation index, BMD initially decreased and then increased. The significant variation in the vertebra microstructure at the different developmental stages might be closely related to its function. These results indicate that the microstructure and element contents of vertebrae in O. mykiss changes significantly during development and the relative results could provide more reliable data for age, group, and taxonomic identification of fish.

The cobia, Rachycentron canadum (Linnaeus, 1766), is an important aquaculture species in cage and other intensive systems. This species has many advantages such as fast growth rate, excellent meat quality, and high market value, making cobia an excellent candidate species for commercial aquaculture. However, long-term artificial breeding of cobia has reduced gene exchange and population genetic diversity. To better protect germplasm resources, molecular markers provide a powerful tool in developing the breeding industry of cobia. Microsatellites are widely distributed, large in number with high polymorphism, and have long been considered important molecular markers for genetic diversity and marker-assisted breeding. More polymorphic microsatellite markers need to be developed for cobia because the number of published polymorphic simple sequence repeat (SSR) loci is very limited. In this study, Micro Satellite (MISA) software was used to identify SSR loci based on the genome sequencing data of cobia. We analyzed the distribution, quantity, and composition characteristics of the SSR loci to develop polymorphic microsatellite markers. The identified markers were used to evaluate the genetic diversity in five cultured populations.In this study, a total of 424 827 SSR loci were identified in the genome data of cobia, among which mononucleotides, dinucleotides, and trinucleotides accounted for 50.50%, 30.23%, and 14.02% of the total SSRs, respectively. Among all the repeat units contained in the total SSRs, A/T was the predominant repeat type of the mononucleotide repeats; AT/AT and AC/GT were the dominant repeat types of dinucleotides; AAT/ATT and AGG/CCT were the dominant repeat types of trinucleotides. Repeat numbers of the SSR core sequences in the genome of cobia ranged from 4 to 275 times. The predominant repeat number of the mononucleotide SSR was ten and the predominant number of the dinucleotide and trinucleotide SSR were six and four, respectively. A total of 173 518 SSR loci had a length of ≥20 bp, accounting for 47.98% of the total number of SSRs in the genome. These results indicated that the SSR loci in the genome of cobia were of a high frequency, rich variety, and with high polymorphic potential.Unigenes obtained by the genome sequencing of cobia were used to detect and analyze the SSR loci information using MISA software. The numbers and types of SSR sequences on the single-stranded DNA of the genome were counted. SSR sites in cobia genome mainly contain mononucleotide, dinucleotide, trinucleotide, tetranucleotide, pentanucleotide, and hexanucleotide repeats. The screening criteria for the polymorphic SSR loci was set as "mononucleotide repeat units with repeats at least 10 times; dinucleotides with repeats at least six times; trinucleotides, tetranucleotides, pentanucleotides, and hexanucleotides with repeats at least four times". Subsequently, based on the information of SSR loci screening, 100 candidate loci were randomly selected to design and synthesize primers for amplification. A total of 16 DNA samples from different cultured populations were used as templates. Multiple PCR amplifications were performed to screen ideal polymorphic SSR loci and suitable PCR primers. PCR products were detected using capillary fluorescence electrophoresis. The GeneMapper 4.1 software was used to analyze the accurate sites of the amplified sequences. Based on the genotyping data of the 100 SSR loci, SSR loci with high polymorphism were selected to analyze the genetic diversity of five cultured populations of cobia.The screening analysis results revealed a total of 344 820 SSR loci were detected in the genome of cobia. Among these SSR (with 1–6 nucleotide as repeat units), the top three repeat types were mononucleotide, dinucleotide, and trinucleotide, accounting for 50.49%, 30.23% and 14.02% of the total detected SSRs, respectively. Among the repeating units included in the detected SSRs, the mononucleotide repeats were dominated by A/T type, accounting for 46.34% of the total detected SSRs; AC/GT was the dominant repeat unit type of dinucleotide, accounting for 21.81% of the total detected SSRs. The number of SSR core sequence repeats in the total detected SSRs fluctuated in the range of 4 to 275 times. The predominant number of repeats of mononucleotide SSR was ten, and the predominant number of repeats of dinucleotide SSR was six. In this study, the length of ≥12 bp was set as the standard for screening high polymorphic SSR loci. A total of 361 684 SSR loci were obtained. However, the SSR loci with fragment lengths of 12–19 bp accounted the largest number, with a total of 188 166; these loci accounted for 52.02% of the total number of SSRs. Among the selected 100 candidate loci for genotyping, a total of ten polymorphic SSR markers were obtained. These markers were used in the genetic diversity analysis of five cultured populations collected in Beihai (RC-BH), Lingshui (RC-LS), Naozhou (RC-NZ), Xuwen (RC-XW), and Sanya (RC-SY). A total of 69 alleles were detected from 145 individuals, the average observed heterozygosity (Ho) was 0.628, and the average expected heterozygosity (He) was 0.706, and the mean polymorphism information content (PIC) was 0.653. The inbreeding coefficient (Fis) of the ten loci in the five cultured populations ranged from –0.317 to 0.270. The genetic distance between the five cultured populations ranged from 0.141 to 0.464, and the genetic similarity was 0.629–0.868. The results were similar to that of previous research using published markers, indicating that the polymorphic markers screened from the genome of cobia were of high accuracy and reliability. These polymorphic SSR markers provide strong support for population genetic diversity evaluation and molecular marker-assisted breeding of cobia, and provide effective technical support for the development of the cobia aquaculture industry.

The conversion of coal-based methanol to benzene, toluene, and xylene is an important technology to promote the efficient and clean conversion of coal. However, the control of reaction process on a single catalyst is difficult and the aromatic selectivity is low. Coated ZSM-5 was prepared by steam-assisted crystallization, in which ZSM-5 with a Si/Al ratio of about 50 was mixed into dry gel with a Si/Al ratio of 220. Under the catalysis of the coated ZSM-5, the two-step reaction of methanol to olefin and olefin aromatization was performed to improve the aromatic selectivity. The effect of coating ratio on the catalytic performance of the prepared ZSM-5 was investigated. The results show that when the coating ratio was less than 0.5, the silicon and aluminum species in the gel could be coated on the surface of parent ZSM-5. The coating structure with high Si/Al ratio promoted the conversion of methanol to light olefin, and further enhanced the stepwise aromatization process of methanol. The aromatic selectivity increased from 12.9% of the original powder to 14.5% and the selectivity of light aromatic in total aromatic products also increased from 61.8% to 66.5%. When the coating ratio increased to 2, some silicon and aluminum species nucleated independently outside the original powder to form small crystal. Although the total aromatic selectivity increased to 15.2%, the small crystal promoted the alkylation of light aromatic to form heavy aromatic hydrocarbons, while the light aromatic selectivity decreased.

[Objective] The granularity characteristics of surface sediments in the Arexunula Desert in Xinjiang Uygur Autonomous Region were studied in order to understand the characteristics of surface sediments in the study area and the factors affecting the granularity distribution of sediments. [Methods] Granularity was divided into grains, granularity parameters, and fractal dimension of the surface sediments for the Arexunula Desert and sand dunes in Xinjiang were analyzed. [Results] ① The granularity size of surface sediments in the study area was 284.63 μm, with medium sand dominant, accounting for 48.93%. The skewness was -0.18, with a negative bias, close to the sand source. The transport medium had strong dynamics. The sorting coefficient was 1.10, and the sorting performance was excellent. The kurtosis value was 1.01, which was a normal peak state, and the sediment particles were evenly distributed. ② The skewness values of surface sediments of mobile sand dunes and semi-fixed sand dunes were -0.13 and -0.08, respectively, which indicated negative skewness and medium skewness, respectively, and there was a large amount of coarse gravel in both types of dunes. The sorting coefficients were 1.66 and 1.76, both of which were medium, and the sediment granularity distribution was relatively uniform. The kurtosis values were 1.10 and 1.12, respectively, which were normal and narrow peaks, indicating that the coarse-grained sediments of sand dunes were relatively concentrated in the desert. ③ The average granularity values of surface sediments from the bottom of the windward slope to the bottom of the leeward slope were 289.58, 310.44, 290.92, 277.64, 275.36, 310.34 and 306.68, 337.78, 290.36, 277.68 μm, respectively. The coarse-particle sediments of the two types of sand dunes were concentrated in the windward slope. The coarse particle sediment content of the semi-fixed dune windward slope was higher than that of the mobile dune windward slope, and the semi-fixed sand dune had stronger sand interception ability. The sorting coefficients of mobile sand dunes and semi-fixed sand dunes changed from the bottom of the windward slope to the bottom of the leeward slope. The former fluctuated greatly and showed a W-shape, and the latter changed little and was V-shaped. Shrub vegetation made the sorting coefficient change trend turn at the top of the dune. ④ The fractal dimension value of the grain size of desert surface sediments was 1.35, and the fractal dimension values of the particle size of semi-fixed sand dunes and mobile sand dunes were 1.59 and 1.34, respectively. The fluctuation intensity of fractal dimension affected the uniformity of sediment particle distribution, soil fertility, and vegetation growth. [Conclusion] The Arexunula Desert is close to the sand source, and the coarse-grained sediments of the dunes were relatively concentrated in the desert. Shrubland is one of the factors affecting the granularity distribution characteristics of surface sediments.

As the last step of the nuclear fuel cycle, nuclear waste reprocessing is essential to the safe utilization and sustainable development of the nuclear industry and nuclear energy. Vitrification is currently internationally recognized as the best solution for the treatment of high-level radioactive waste, and it is also the only high-level waste disposal method that realizes engineering applications. The cold crucible induction melting (CCIM) vitrification technology is one of the key research directions of high-level waste liquid vitrification technologies. As an important part of the cold crucible, the bottom affects the magnetic permeability, sealing, strength and leakage process of the cold crucible. In order to improve the pouring efficiency during cold crucible melting process, the magnetic induction intensity near the discharge port needs to be enhanced. The effects of the design of the crucible bottom on the magnetic induction intensity and electromagnetic loss inside the cold crucible were studied. The 3D electromagnetic induction models of cold crucibles with different bottom structures were established by using the AC/DC module of COMSOL Multiphysics software. The simulation results show that changing the number of slits has little effect neither on the magnetic field inside the crucible, nor on the magnetic field and the electromagnetic loss at the bottom of the crucible. The slit width of crucible bottom increasing from 5 mm to 20 mm, the magnetic flux density inside the crucible increases by about 4%, and the electromagnetic loss of the glass melt domain in the crucible increases by about 1.7 kW (the proportion increased by about 6%). Increasing the length of the slits from 90 mm to 115 mm, the magnetic flux density near the center of the crucible bottom increases by 0.1-1.25 mT, and the electromagnetic loss of the glass melt near the bottom increases by 1.6% (about 0.4 kW). Accordingly, the magnetic permeability and the heating efficiency of the cold crucible can be improved by increasing the slit width. The magnetic induction intensity near the discharge port can be improved by increasing the length of the slits, thereby improving the leakage efficiency. In practical applications, it is not only necessary to improve the heating efficiency of the cold crucible, but also to avoid the leakage of the glass melt at the bottom of the cold crucible during the melting process. Therefore, the structural design of the cold crucible bottom needs to comprehensively consider factors such as the magnetic permeability, the heating efficiency, the strength of the crucible and the processing of water-cooled components inside the slits.

In order to study the changes of the structure and chemical durability with Fe/P mole ratio(r(Fe/P)), a series of P2O5-Fe2O3-Al2O3-Na2O-ZrO2 glass-ceramic samples with different Fe/P mole ratios were prepared by the melting-quenching method. X-ray diffraction was used for phase analysis, and Raman spectroscopy, X-ray photoelectron spectroscopy and M-ssbauer spectroscopy were used for structural analysis. n(Fe3+)/(n(Fe2+)+n(Fe3+)) mole ratios increase with the increase of Fe/P mole ratio when the Fe/P mole ratio is less than 0.18. When the Fe/P mole ratio is between 0.18 and 0.32, n(Fe3+)/(n(Fe2+)+n(Fe3+)) fluctuates around 60%. The samples with Fe/P mole ratio between 0.2 and 0.3 have the best chemical durability and relatively low crystal fraction.

To improve estimating accuracy in the traditional mean rank or median rank estimation method, an improved mean rank is proposed in the correction principle of rank estimation function as the cumulative distribution function of samples by adjusting the applicable points of natural mean rank. Then a least squares estimation is performed by directly fitting the cumulative distribution function. Based on the hypothesis of Weibull distribution under small sample, the parameter estimations under different ranks are calculated by Monte Carlo simulation. The results indicate that the relative error on calculating scale parameter using the improved mean rank method for the Weibull distribution with different parameters is less than 9.5% under the condition of sample size not less than 4. Furthermore, the relative error on calculating mean time between failures using the improved mean rank method is less than 8.7%, while the relative errors using traditional methods are higher than 16%. From calculated results, proposed method can effectively improve the parameter estimation accuracy for Weibull distribution.

The deep carbonate buried hills are widely distributed in the Nanpu Sag of Bohai Bay Basin. They have experienced multiple stages of tectonic movement and show a tectonic pattern of alternating sub-sags and uplifts. Exploration discoveries have been achieved in multiple structural belts and layers. In recent years, with the deepening of exploration, many exploratory wells deployed on the slope belt and the downdip area were failed, and the exploration of deep buried hills has stagnated. To clarify the potential and exploration direction of buried hills, on the basis of improvement of seismic data, starting from the three major accumulation elements of hydrocarbon supply window and supply mode, high-quality reservoir type and trap type, the re-evaluation of accumulation conditions and the re-understanding of main controlling factors of accumulation were carried out. The deep Paleozoic carbonate buried hills in the Nanpu Sag develop multiple sets of reservoir-caprock assemblages, [JP] with good physical properties, high-quality source rocks, and favorable hydrocarbon accumulation conditions. Oil and gas enrichment is controlled by multiple factors such as hydrocarbon supply mode, window, type of trap and reservoir, and there are various types of oil and gas reservoirs. The hydrocarbon supply window controls the formation of hydrocarbon accumulation, the type of trap determines the type of oil and gas reservoir, and the dominant reservoirs formed by fault fracture-supergenic karst and fracture-burial karst generated by multi-stage karstification control the enrichment and high yield. The comprehensive evaluation of the accumulation conditions shows that the slope area and the trough area of the Nanpu No. 1 and No. 2 structural belts as well as the inner Cambrian buried hills of the Nanpu No. 2 and Nanpu No. 3 structural belts are important directions for the next exploration. Through the integrated application of geological research and exploration technology, several favorable[JP] exploration targets have been classified and evaluated. Overall breakthroughs have been made in the exploration of carbonate buried hills in the Nanpu Sag, and good exploration results have been achieved.

An elderly woman with a chronic course of disease presented with progressive weakness of lower limbs, heart failure, carbon dioxide retention, periorbital pigmentation, increased hair around the eyebrows, as well as multiple positive autoantibodies. After multidisciplinary team discussion, restrictive ventilatory dysfunction caused by significantly decreased diaphragm movement was taken as a breakthrough to sort out the etiology step by step. Based on clinical manifestations, serological and imaging features, as well as immunohistochemical staining of quadriceps femoris pathological complement, the final diagnosis of inflammatory myopathy associated with anti-mitochondrial antibodies was established. After correcting heart failure, intermittent non-invasive ventilation and rehabilitation training, clinical symptoms and functional status of the patient were significantly improved. The joint participation of the multidisciplinary team to identify the causes and solve problems in diagnosis and treatment decision-making reflects the great significance of multidisciplinary collaboration in rare diseases.

Since traditional matrix factorization algorithms are mostly based on shallow linear models,it is difficult to learn latent factors of users and items at a deep level.When the dataset is sparse,it is inclined to overfitting.To deal with the problem,this paper proposes a biased deep distance factorization algorithm,which can not only solve the data sparse problem,but also learn the distance feature vectors with stronger characterization capabilities.Firstly,the interaction matrix is constructed through the explicit and implicit data of the user and the item.Then the interaction matrix is converted into the corresponding distance matrix.Secondly,the distance matrix is input into the depth of the bias layer by row and column respectively.The neural network learns the distance feature vectors of users and items with non-linear features.Finally,the distance between the user and the item is calculated according to the distance feature vectors.Top-N item recommended list is generated according to the distance value.The experimental results show that Precision,Recall,MAP,MRR and NDCG of this algorithm are significantly improved compared to other mainstream recommendation algorithms on four different datasets.

In order to further explore the shaping effect and wearing comfort of shaping clothing, three methods for evaluating the comfort of shaping clothing are summarized and analyzed, namely psychological evaluation, physiological evaluation, and physical evaluation. The advantages and limitations of various methods are summarized. And the influencing factors of the comfort of shaping clothing from three levels of human body shape, structure design and material performance are also analyzed. Finally, it is pointed out that in the future, based on the analysis of human body shape, structural optimization can be carried out according to different shaping requirements, and new technology can be applied to develop comfort surface accessories. Combined with qualitative and quantitative evaluation methods, the influence of local feeling on overall comfort can be analyzed, which can provide reference for the development of the comfort of shaping clothing.

NiTi-based shape memory alloys (SMAs) are one of the SMAs with most outstanding properties, and have been widely applied in aviation, space, electronics, construction, biomedicine and other fields. In recent years, the elastocaloric refrigeration based on elastocaloric effect (eCE) of NiTi alloys has attracted increasing attentions since their excellent mechanical properties, huge elastocaloric strength and good machinability. However, conventional binary NiTi alloys cannot meet the requirements of long-life service since their large superelastic stress hysteresis and poor cyclic stability of superelasticity and eCE. In this paper, the research progress of eCE for NiTi-based alloys was reviewed. The effect of doping alloying element, thermomechanical treatment and novel processing techniques on eCE of NiTi-based alloys were surnmarized. In addition, the developed elastocaloric devices or prototypes based on NiTi-based alloys were also briefly introduced. However, the current researches on NiTi-based elastocaloric materials and the development of prototypes are still in the experimental stage. To realize their commercial application requires further in-depth research and optimization. In the future, the research priorities for the former will concentrate on material miniaturization, alloying or applying special treatment as well as changing circulation methods and so on. On the other hand, the research priorities for the latter will focus on improving heat transfer efficiency, strengthening heat exchange, reducing friction and other losses, and improving mechanical loadings as well as circulation modes.

[Purpose/Significance] In the era of knowledge economy, enterprise knowledge is considered to be the main driving force for the development of enterprises, how to find the law of knowledge dissemination and carry out effective knowledge dissemination has become an increasing concern of scholars. [Method/Process] On the basis of the classic infectious disease model SEIR model, enterprises are divided into knowledge innovation enterprises and general knowledge unknown enterprises. On the basis of considering that knowledge innovation enterprises can carry out knowledge innovation, combined with the influence of enterprise knowledge dissemination willingness on enterprise knowledge dissemination, a B-STEHIR model considering the willingness of enterprise knowledge dissemination under the guidance of knowledge innovation of innovative enterprises is constructed, and the average field equation of the model is proposed. At the same time, the basic regeneration number is solved by the next-generation matrix method, and the model is simulated using Matlab2020a. [Result/Conclusion] The results show that under the guidance of knowledge innovation of innovative enterprises, the factor of willingness to disseminate plays an important role in the process of enterprise knowledge dissemination, and knowledge spreads more slowly in the knowledge dissemination model that considers the willingness to spread compared with the knowledge dissemination model that does not consider the willingness to spread The stronger the willingness to disseminate innovative knowledge, the slower the dissemination of general knowledge, and enterprises and governments can take various measures to promote the effective dissemination of corporate knowledge.

POI (point of interest) recommendation is an important personalized service in the LBSN (location-based social network) which has wide applications such as popular sights recommendation and travel routes planning.Most existing collaborative filter algorithms make recommendation according to user similarity and location similarity,they don’t consider the trust relationship between users.And trust relationship is helpful to improve recommendation accuracy,robustness and user satisfaction.Firstly,the propagation property of trust and distrust relationship was analyzed.Then,the measurement and computation method of trust were given.Finally,a hybrid recommendation system which combined user similarity,geographical location similarity and trust relationship was proposed.The experiments results show that the hybrid recommendation is obviously superior to the traditional collaborative filtering in terms of results accuracy and user satisfaction.

The previously proposed short comparable encryption (SCE) scheme can infer the plaintext relationship by comparing the ciphertexts relationship as well as ensuring data security in Internet of things.Unfortunately,it will incur high storage and computational burden during the process of comparing ciphertexts and generating tokens.To this end,an efficient short comparable encryption scheme called SCESW was proposed,which was utilizing the sliding window method with the same size window.Formal security analysis shows that the scheme can guarantee weak indistinguishability in standard model as well as data security and integrity.The experimental results demonstrate that the storage of the SCESW scheme is 1 t (t＞1) times shorter than that of the SCE scheme and the efficiency of the SCESW scheme is superior to that of the SCE scheme.

The common development of graptolite in marine shale of Southern China has a close relationship with the formation of marine shale gas, but whether graptolite has hydrocarbon generating ability of shale gas has not been directly confirmed by relevant experiments. In this study, pure graptolite from black graptolite shale was selected and the graptolite sample was hand-picked for the experimental study on pyrolysis hydrocarbon generation. The results show that the graptolite is a good parent material. The carbon content of the graptolite is high, accounting for most carbon sources of graptolite shale. The main products of pyrolysis hydrocarbon generation are shale gas and light oil, which accounts for more than 94% of the total hydrocarbon generation products, whereas the shale gas accounts for 54%. The pyrolysis product is similar to that between type-Ⅲ organic matter (OM) and type-Ⅱ OM is more similar to that of type-Ⅲ OM, which is mainly gaseous hydrocarbon products. The hydrocarbon generation ability of graptolite may be higher during thermal maturation process, which is closely related to the genesis of widespread shale gas in Southern China at present.

Pressure disturbance propagation was investigated using the steady state replacement method, the relationship between moving boundary and time was obtained. An unstable seepage model in shale gas reservoirs was established considering the effects of desorption, diffusion, slip and moving boundary. Using Laplace transform, the pressure characteristics equation was solved for the condition of internal boundary being constant production and outer boundary being the moving boundary. Subsequently, combining the parameters of shale gas in southern China, unstable seepage pressure characteristics and its influence factors of shale gas reservoir were analyzed using MATLAB software. The results indicate that the pressure propagation is characterized by moving boundary effect during shale gas exploitation, which means that moving boundary is propagated outwards with the propagation velocity decreasing gradually. Under the effect of moving boundary or shale gas desorption, the pressure propagation velocity decreases and the reservoir pressure drop slows down. With the increasing of the diffusion coefficient, the reservoir pressure drop slows down and the effect of diffusion coefficient decreases gradually. In the process of gas reservoir exploitation, diffusion and slip contribute more and more to gas production, acting as the dominant factors, while the contribution of flow and desorption level off after decreasing. Key words: shale gas, unstable seepage, pressure propagation law, mathematical model, moving boundary

The Jiangxi Lengshuikeng ore field, characterized as porphyry deposits and volcanic sedimentary hydrothermal reworking deposits, is one of the major Ag-Pb-Zn ore concentration areas in Wuyi Mountain area. There has been much research carried out on mineralization, the metallogenic model, and ore-controlling structure of the Lengshuikeng deposit. However, it is still unclear about the relationship of different geological bodies with mineralization and magmatism. In this paper, a description of a zircon LA-ICP-MS U-Pb geochronology approach and its implementation on the volcanic rock of Daguding Formation and ore-bearing granite porphyry is given. The crystal tuffs from the top and bottom of Daguding Formation and ore bearing granite porphyry yield U-Pb age of 161.3±1.3 Ma, 160.75±0.96 Ma and 168.09±0.80 Ma, respectively. These results indicate that there were three stages of volcano-magmatic activities in the Lengshuikeng ore field with ages of 164-170 Ma, 157-161 Ma, and 140-146 Ma, respectively. The 157-161 Ma is the main metallogenic epoch of the volcanic sedimentary-hydrothermal reworking type deposit and porphyry type deposit. The discovery of the late Jurassic volcanic rocks in Lengshuikeng provides the important geological evidence for the detailed study of the Mesozoic tectonic regime transition in South China.

Background and objective Lung lymphoepithelioma-like carcinoma is a rare subtype of large cell carcinomas of the lung. The aim of this study is to retrospectively analyze the clinical characteristics, surgical methods, laboratory inspection, chemotherapy, radiotherapy and prognosis of LELC. Methods From 2004 to 2008, clinical data were collected from 21 patients who were treated in Shanghai Chest Hospital. The correlation between clinicopathological characteristics and prognosis was evaluated. Results Of the 21 patients, 15 patients had lobectomy; 4 patients had wedge resection; 1 patient had pneumonectomy and 1 patient had sleeve resection. 12 patients received chemotherapy and 3 patients received radiotherapy after operation. Until 2009-4-31, 4 patients died, and the median survival time (MST) was 49 months. Conclusion Lymphoepitheliomalike carcinoma of the lung is a very rare and unique subtype of large cell carcinomas of the lung, which has a better prognosis with surgical, chemotherapy and radiotherapy.

In order to assess the antibiotic resistance of Escherichia coli and its transmission risk in a rice-frog coculture system in Zhejiang Province, this study collected E . coli from isolated soil, field water, and frog feces from the rice-frog coculture systems in four different areas of Zhejiang Province. The collected isolates were identified by 16S rRNA sequencing, while their antibiotic-resistant phenotypes were determined by Kirby-Bauer (K-B) method. PCR was used to identify the antibiotic-resistant genotypes and integrons, while conjugative transfer experiments were used to assess resistance transmission characteristics. The results showed a high prevalence of antibiotic resistance in the 82 strains of E . coli tested, primarily against tetracycline, sulfisoxazole, amoxicillin, and erythromycin. Most of these strains exhibited multidrug resistance, with the Fuyang area demonstrating the highest resistance rate compared to the other three areas. Further PCR analysis identified the sul1 gene as the most frequently detected resistance gene (63.41%), followed by bla TEM , tetA , and tetB . Among the 16 antibiotic resistance genes (ARGs) detected, the Fuyang isolates consistencly exhibited higher detection rate of 9 ARGs in comparison to the other regions. Additionally, the integrase gene intI1 displayed the highest detection rate, with 14 strains (34.15%) of integrase-positive bacteria carrying gene cassettes. Four different gene cassette compositions were observed, with dfrA1-aadA1 and dfrA17-aadA5 being the most common combinations. Conjugative transfer experiments demonstrated successful transfer of gene cassettes in 4 out of 14 donor bacteria, with conjugation transfer frequencies ranging from 4.32×10 -5 to 7.13×10 -4 . These findings revealed the severity of resistance in the Fuyang area among the four regions. Integrons play a significant role in mediating the resistance to multiple antibiotics in E . coli , facilitating the potential spread of resistance gene cassettes between different bacteria. Overall, this study provides valuable insights into the resistance status and transmission characteristics of E . coli in the rice-frog coculture system in Zhejiang Province, providing a theoretical basis for ensuring the food safety of rice crops.

We analyzed the biological and genome characteristics of a phage infecting enteroinvasive Escherichia coli (EIEC), aiming to provide resources and a reference for the prevention and treatment of EIEC. With the EIEC preserved in our laboratory as the host bacterium, one strain of phage was isolated from the effluent sample from a chicken farm in Huzhou, Zhejiang and named ΦEP1. The titer, optimal multiplicity of infection, one-step growth curve, temperature, pH value, chloroform and bile salt sensitivity of ΦEP1 were determined by the double-layer agar plate method. The morphology of the phage was observed by transmission electron microscopy. The biocontrol effects of ΦEP1 in different food matrixes and the protective effect of this phage on Caco-2 cells were tested. The phage ΦEP1 showed the optimal multiplicity of infection of 0.1, the titer of 1.3×10 10 PFU/mL, strong tolerance to temperature, pH, chloroform, and bile salt, and a broad host spectrum. Furthermore, it expressed lysis activity against multiple strains of multiple antibiotic-resistant pathogenic E . coli and Shigella with different serotypes. Phage ΦEP1 had an incubation period of 10 min, an outbreak period of 80 min, and an outbreak volume of 48 PFU/cell. According to the morphology observed by transmission electron microscopy, phage ΦEP1 belonged to the order of Caudovirales , and it had a good protective effect on Caco-2 cells. Phage ΦEP1 had a genome of 87 182 bp with the GC content of 39.80%, 128 putative open reading frames, and no antibiotic resistance genes or virulence genes. ΦEP1 inhibited the growth of EIEC in artificially contaminated milk and beef and eliminated EIEC in cell protection experiments. It significantly increased the survival rate of Caco-2 cells and down-regulated the expression of interleukin (IL)-6 and IL-1β to reduce inflammation. We obtained an EIEC-targeting phage ΦEP1 with a high titer and strong tolerance to the environment, which provided a basis for the application of phages in food preservation and other fields.

Blood purification is one of the commonly used techniques for the rescue of critically ill patients, which is used for acute and chronic kidney injury caused by various causes and renal replacement therapy (RRT) for a variety of critical diseases. Its main working principle is to drain the human blood into a variety of dialyzers through the artificial tube, exchange substances through a variety of ways, and remove harmful substances and some metabolites from patients' body. Then the purified blood is transfused back to the body, so as to maintain the patient's internal environment relatively stable. At present, there are different models of hemodialysis machines in clinical practice, but they are bulky and unable to move, and the method of heat dissipation is single, which cannot meet the needs of hemodialysis treatment in transport patients. Therefore, the medical staff of the Second Affiliated Hospital of Zunyi Medical University designed and developed a hemodialysis machine, which is suitable for patients who demand hemodialysis treatment during transport, and obtained the National Invention Patent of China (ZL 2020 1 0864737.3). The hemodialysis machine comprises a main body of the hemodialysis machine and a mobile vehicle. The main body of the hemodialysis machine is placed in the bottom of the mobile vehicle, and a protective cylinder with fixed airbags is designed around the main body of the hemodialysis machine. The fixed airbag is connected to the air storage tank through the pipeline, the air storage tank is connected to the Venturi tube through the control valve, and the throat of the Venturi tube is connected to the disinfection tank and cooling water tank. The outlet end of the Venturi tube is connected with the cooling pipe inside the main part of the hemodialysis machine and the sprinkler head placed on the top of the main body. By adding a mobile vehicle and designing an airbag and protective cylinder, the hemodialysis machine can be applied to the hemodialysis treatment during the transportation of patients. By designing the heat dissipation pipe, the main body of the hemodialysis machine can be cooled, the temperature of the hemodialysis machine can be reduced, and the hemodialysis machine can still work when the fan is damaged. By designing the sprinkler head, it is convenient to automatically disinfect the main screen and control keys of the hemodialysis machine, reduce the risk of cross infection of medical staff in the operation, and increase the safety and practicability of the hemodialysis machine. The hemodialysis machine is convenient, safe and efficient, which can be widely used in the hemodialysis treatment during transported patient, and is worthy of clinical promotion.

Patients who are bedridden are for a long-time prone to develop bedsores, especially in the hip and sacral areas and limbs, which causes eczema, ulcers, infection and other complications, resulting in pain and more medical costs. Therefore, the medical staff of the Second Affiliated Hospital of Zunyi Medical University designed and developed a kind of anti-bedsore turning pad, and has obtained the national utility model patent (ZL 2021 2 3004923.9), which is suitable for various long-term bedridden patients. The anti-bedsore turning pad includes the center axis of the turning pad, and ventilation pad 1 and ventilation pad 2 designed on the left and right of turning pad center axis. Under the ventilation pad 1 and the ventilation pad 2, the air pad 1 and the air pad 2 are respectively designed. There is a bedspread connected with ventilation pad 1 and ventilation pad 2 on the inflatable pad 1 and the inflatable pad 2. Through the design of inflatable pad 1 and inflatable pad 2, the left and right of the anti-bedsore turning pad can be lowered or raised independently, which is convenient for the patient's body to tilt and turn over, and can significantly reduce the number of nursing staff and the burden of nursing staff when turning over. In addition, it is convenient to replace the force site at any time and reduce the occurrence of pressure ulcers caused by long-term pressure on the force site. Through the design of ventilation cushion 1 and ventilation cushion 2, the internal gas flow of the turning pad can be made, and the ventilation between the patient and the turning pad can be kept dry, so as to reduce the occurrence of eczema, ulcers or infection and other complications, and ultimately reduce the occurrence of bedsores. In addition, through the design of the most superficial limb pad, the patient's limb can be appropriately elevated or massaged, which increases the comfort of the patient. The anti-bedsore turning pad is simple and effective, and can be widely used in long-term bedridden patients.

Objective: To establish a method for rapid detection of DB-WAX capillary column and determination of the workplace air in 30 kinds of volatile organic pollutants. Methods: In August 2020, N-pentane, n-hexane, methylcyclohexane, octane, Acetone, ethyl acetate, butanone, benzene, 3-pentanone, trichloroethylene, tetrachloroethylene, toluene, butyl acetate, 2-hexanone, Isoamyl acetate, ethylbenzene, p-xylene, m-xylene, amyl acetate, o-xylene, chlorobenzene, styrene, cyclohexanone, P-chlorotoluene, bromobenzene, M-dichlorobenzene, p-dichlorobenzene, O-dichlorobenzene, o-Chlorotoluene, 1, 2 , 4-trichlorobenzene of 30 kinds of substances in air were collected by activated carbon tube. After analysis by carbon disulfide, the analytical solution was analyzed by DB-WAX column and determined by FID detector. Results: The above 30 kinds of volatile organic pollutants had good separation effect, the correlation coefficient of the standard curve was above 0.999, the relative standard deviation was 0.1%-3.2%, the desorption efficiency was 77.0%-117.1% , the lower limit of quantitation was 0.33-5.33 μg/ml, and the lowest quantitation concentration was 0.22-3.55 mg/m(3), the recoveries ranged was 95.4%-104.9%. Conclusion: The method can effectively separate and accurately determine 30 volatile organic compounds in these workplaces, and the method is simple and quick.

Objective: The aim of this study is to understand the epidemiological characteristics of tinnitus among flight support personnel and analyze its audiological characteristics and related risk factors. Methods: The information of tinnitus was collected by a method of cross-sectional investigation using questionnaire survey and audiology test among the flight support personnel of two stations of PLA air force. Results: The incidence of tinnitus among 666 subjects included was 24.2%, the THI grade was mainly grade 1 and grade 2. There were differences in THI scores among groups with different working years, but only differences in tinnitus incidence among groups with different frequency of hearing loss. Multivariate logistic regression analysis showed that grade of high frequency hearing loss（ OR =1.39）, conscious hearing loss（ OR =1.79） and frequency of asking others to repeat words（ OR =1.64） were independent risk factors of tinnitus. The incidence of HF-HL and EHF-HL in ears with tinnitus among 0-5 working years was higher than that without tinnitus, while the incidence of EHF-HL in ears with tinnitus was not different from that without tinnitus among 6-10 and >10 working years. There was moderate correlation between THI scores and SAS standard scores（ r =0.759）, and weak correlation between THI scores and PSQI scores（ r =0.445）. Conclusion: The risk of tinnitus in high-frequency hearing loss and recessive hearing loss is increased; working years can affect the severity of tinnitus, while hearing conditions at different frequencies only affect the incidence of tinnitus; with increasing age, noise exposure plays a role in the occurrence of tinnitus decreasing gradually., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.)

In the WHO new road map for neglected tropical diseases 2021-2030, the disease-specific targets are classified into control, elimination as a public health problem, elimination and eradication, and taeniasis and cysticercosis are targeted for control. The overall prevalence of taeniasis and cysticercosis is low in China, and varies remarkably in regions and populations; however, there are many challenges for elimination of taeniasis and cysticercosis in China. Based on previous taeniasis and cysticercosis control programs, developing a sensitive taeniasis and cysticercosis surveillance-response system, updating criteria for diagnosis of taeniasis and cysticercosis, proposing a national guideline for treatment of taeniasis and cysticercosis, and strengthening interdisciplinary and intersectoral communications and collaborations are urgently needed under the One Health concept.

Objective: To establish a nomogram model for hematoma expansion (HE) prediction after intracerebral hemorrhage (ICH) and evaluate its performance in a multidimensionally way. Methods: A total of 348 ICH patients who were firstly diagnosed and hospitalized in the Second Affiliated Hospital of Soochow University from January 2017 to December 2019 were collected retrospectively. There were 236 males and 112 females, and their age ranged from 18 to 94 (62.0±14.6) years. All patients were divided into HE group ( n =121) or non-HE group ( n =227) according to the presence or absence of HE. The clinical and imaging features were compared between the two groups. Multivariate logistic regression analysis was performed for determining the independent predicting factors for HE prediction and a Nomogram model was established by using these factors. Receiver operating characteristic (ROC) curve, calibration curve, and decision curve analysis (DCA) were used to evaluate the prediction effectiveness, accuracy and clinical practicability of the model, respectively. Bootstrap method was used for internal validation. Results: There were significant differences in onset time, swirl sign, history of anticoagulants administrations, systolic blood pressure when admission, Glasgow coma scale (GCS) scores and RBC distribution width between the two groups[(1.77(1.0, 2.5) h vs 2(1, 3) h, 72 cases (59.5%) vs 94 cases (41.4%), 17 cases (14.0%) vs 15 cases (6.6%), (170.69±29.19) mmHg(1 mmHg=0.133 kPa) vs (163.84±26.07) mmHg, 11(8, 14) scores vs 14(10, 15) scores, 44.3% (41.2%, 46.8%) vs 42.4% (40.1%, 45.3%);respectively, all P <0.05]. Multivariate logistic regression analysis demonstrated that onset time ( OR =0.809, 95% CI : 0.682-1.961, P =0.015), swirl sign ( OR =0.562, 95% CI :0.349-0.905, P =0.018), history of anticoagulants administrations ( OR =0.394, 95% CI : 0.180-1.861, P =0.020), and GCS ( OR =0.881, 95% CI : 0.815-1.952, P =0.001) were the predicting factors for HE. The area under the curve (AUC) of the Nomogram model was 0.735(95% CI : 0.687-0.805), which demonstrated that the model has an ideal prediction effectiveness. The calibration curve showed that the prediction probability of HE of the model fits well with the actual probability, and with high calibration. DCA showed relatively wide range of optional threshold probability of the model (ranging from 14% to 72%), the clinical practicability of this model was high. The internal validation results showed a C-index of 0.703, indicated a good discrimination power. Conclusion: The established Nomogram model can predict the HE of ICH with good prediction effectiveness, discrimination power and with good clinical practicability, which can be capable of providing an intuitive and visual guidance tool for timely identifying ICH patients who may have HE.

Objective: To evaluate the clinical features of preterm infants with a birth weight less than 1 500 g undergoing different intensities of resuscitation., Methods: A retrospective analysis was performed for the preterm infants with a birth weight less than 1 500 g and a gestational age less than 32 weeks who were treated in the neonatal intensive care unit of 20 hospitals in Jiangsu, China from January 2018 to December 2019. According to the intensity of resuscitation in the delivery room, the infants were divided into three groups:non-tracheal intubation ( n =1 184), tracheal intubation ( n =166), and extensive cardiopulmonary resuscitation (ECPR; n =116). The three groups were compared in terms of general information and clinical outcomes., Results: Compared with the non-tracheal intubation group, the tracheal intubation and ECPR groups had significantly lower rates of cesarean section and use of antenatal corticosteroid ( P < 0.05). As the intensity of resuscitation increased, the Apgar scores at 1 minute and 5 minutes gradually decreased ( P < 0.05), and the proportion of infants with Apgar scores of 0 to 3 at 1 minute and 5 minutes gradually increased ( P < 0.05). Compared with the non-tracheal intubation group, the tracheal intubation and ECPR groups had significantly higher mortality rate and incidence rates of moderate-severe bronchopulmonary dysplasia and serious complications ( P < 0.05). The incidence rates of grade Ⅲ-Ⅳ intracranial hemorrhage and retinopathy of prematurity (stage Ⅲ or above) in the tracheal intubation group were significantly higher than those in the non-tracheal intubation group ( P < 0.05)., Conclusions: For preterm infants with a birth weight less than 1 500 g, the higher intensity of resuscitation in the delivery room is related to lower rate of antenatal corticosteroid therapy, lower gestational age, and lower birth weight. The infants undergoing tracheal intubation or ECRP in the delivery room have an increased incidence rate of adverse clinical outcomes. This suggests that it is important to improve the quality of perinatal management and delivery room resuscitation to improve the prognosis of the infants.

Objective: To analyze the hospitalization cost and its influencing factors of imported malaria patients in Guangxi Zhuang Autonomous Region and Yunnan Province, so as to provide insights into the evaluation of the economic burden due to imported malaria, and the guiding of malaria control and the rational allocation of medical resources., Methods: The data pertaining to the hospitalization costs of imported malaria patients admitted to Shanglin County People's Hospital in Guangxi Zhuang Autonomous Region during the period from January 1 through December 31, 2019, and Tengchong Municipal People's Hospital in Yunnan Province from January 1, 2015 to December 31, 2019, were collected, and the epidemiological data of these imported malaria patients were extracted from the Information Management System for Parasitic Diseases Control and Prevention, China. The composition of the hospitalization expenses was analyzed using a descriptive method. In addition, the factors affecting the hospitalization expenses of imported malaria patients were identified using a univariate analysis and a recursive system model., Results: A total of 206 imported malaria patients were included in this study, including 194 men (94.17%) and 12 women (5.83%). The mean length of hospital stay was 5.00 days per patient and the median hospitalization expenses were 2 813.07 Yuan per time, in which the expenses for laboratory examinations were the highest (45.31%, 1 274.62/2 813.07). Univariate analysis showed that hospital ( z = 5.43, P < 0.01), type of malaria ( χ 2 = 34.86, P < 0.01) and type of payment ( χ 2 = 7.72, P < 0.05) were factors affecting the hospitalization expenses of imported malaria patients. Recursion system modeling revealed that the total effects on hospitalization expenses of imported malaria patients included length of hospital stay (0.78), selection of hospital (0.34), basic medical insurance for urban and rural residents (0.19), new rural cooperative medical care (0.17), Plasmodium falciparum malaria (0.15), gender (0.11) and P. vivax malaria (0.09)., Conclusions: The hospitalization expenses of imported malaria patients are affected by multiple factors in Guangxi Zhuang Autonomous Region and Yunnan Province, in which the length of hospital stay is the most predominant influencing factor. A reduction in the length of hospital stay is effective to decrease the hospitalization expenses of imported malaria patients.

Cyanobacteria is one of the promising microbial chassis in synthetic biology, which serves as a typical host for light-driven production. With the gradual depletion of fossil resources and intensification of global warming, the research on cyanobacterial cell factory using CO2 as carbon resource is ushering in a new wave. For a long time, research focus on cyanobacterial cell factory has mainly been the production of energy products, such as liquid fuels and hydrogen. One of the critical bottlenecks occurring in cyanobacterial cell factory is the poor economic performance, which is mainly caused by the inherent inefficiency of cyanobacteria. The problem is particularly prominent for these extremely cost-sensitive energy products. As an indispensable basis for modern industry, polymer monomers belong to the bulk chemicals with high added value. Therefore, increasing attention has been focused on polymer monomers which are superior in overcoming the economic barrier in commercialization of cyanobacterial cell factories. Here, we systematically review the progress on the production of polymer monomers using cyanobacteria, including the strategies for improving production, and the related technologies for the application of this important microbial cell factory. Finally, we summarize several issues in cyanobacterial synthetic biology and proposed future developing trends in this field.

A 57-year-old man was admitted to hospital with diarrhea for 10 months and dizziness for 4 months. The patient had 1-2 liters watery stool per day, without pyogenic blood or abnormality in gastroenteroscopy examination. The level of hemoglobin and albumin was generally normal, and fasting test was positive. At the same time, he was accompanied with hyperalgesia of lower limbs and orthostatic hypotension. After the discussion of multiple disciplinary teams, the patient was diagnosed with amyloidosis by sural nerve biopsy, myocardial MRI, and the assays of urine immunoelectrophoresis and serum free light chain. Light chain amyloidosis was confirmed after excluded the diagnosis of familial amyloidosis. The patient was improved after courses of chemotherapy with melphalan and dexamethasone.

Abstract: Objective To determine the purine adenylate [adenosine triphosphate （ATP）, adenosine diphosphate （ADP）, adenosine monophosphate （AMP）] content in the muscles of both hind limbs of rats at different postmortem interval （PMI）, calculate the changes in the total adenine nucleotide （TAN） content and the adenylic-acid energy charge （AEC）, and explore their relationship with PMI. Methods Healthy rats were sacrificed by cervical dislocation and kept at 20 ℃. The muscles of their hind limbs were extracted at 0, 24, 48, 72, 96, 120, 144, and 168 h after death. Reversed-phase high performance liquid chromatography was used to determine the content of purine adenylates, the TAN and AEC of the muscles of the both hind limbs were calculated, and the related regression equations of their relationship with PMI were established. Results Within 168 h of death of rats, the trend of ATP change was different from ADP, and the content of AMP continuously increased. The TAN value gradually increased with the extension of PMI, and the AEC showed a downward trend within 168 h after death. Among them, the patterns of AEC changes with PMI were obvious, the correlation coefficient was high （ R 2 =0.903）, and the curve fitting relationship was good; the fitting relationship between ATP, ADP, AMP, TAN and PMI was poor （ R 2 =0.198-0.754）. Conclusion The postmortem change patterns of AEC provide new research ideas for PMI estimation in the forensic field., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Forensic Medicine.)

Objective: To investigate the relationship between the expression of DNA methyltransferase 3b (DNMT3b) and the methylation of SEPT9 gene, and their application prospects in the diagnosis and treatment of colorectal cancer. Methods: Seventy-five cases of colorectal cancer and adjacent tissues, 68 cases of colorectal high-grade internal neoplasia tissues (referred to as precancerous tissues) and high-grade internal adjacent neoplasia tissues (referred to as adjacent precancerous tissues) were collected. Pyrosequencing was used to detect the methylationlevel of SETP9. Real-time quantitative polymerase chain reaction (RT-qPCR) was used to examine the mRNA expressionof SEPT9 and immunohistochemistry(IHC) was applied to detect the protein expressions of SETP9 and DNMT3b. Liposome-mediated method was used to transfect DNMT3b siRNA and negative control siRNA into HT-29 cells. Five groups including DNMT3b siRNA 15 nmol/L group, DNMT3b siRNA 30 nmol/L group, negative control siRNA 15 nmol/L group, negative control siRNA 30 nmol/L group and blank control group were set up. Pyrosequencing was applied to determine the methylation level of SEPT9 and mRNA expression of DNMT3b in each group. Results: The methylation rates of SEPT9 gene in colorectal cancer tissues, adjacent tissues, precancerous tissues and adjacent precancerous tissues were (76.8±6.5)%, (14.4±2.6)%, (34.6±5.0)% and (7.4±1.2)%, respectively, which was highest in colorectal cancer tissue ( P <0.001). The relative expressions of SEPT9 mRNA were 0.18±0.03, 0.89±0.41, 0.69±0.41 and 1.01±0.21, respectively, which was lowest in colorectal cancer tissue ( P <0.001), while there were no statistically significant differences in adjacent tissues, precancerous tissues and adjacent precancerous tissues ( P >0.05). The positive rates of SEPT9 protein expression were 12.0% (9/75), 53.3% (40/75), 55.1% (38/69) and 62.3% (43/69), which was lowest in the colorectal cancer tissue ( P <0.001), while there were no statistically significant differences in the adjacent group, precancerous group and adjacent precancerous group ( P >0.016 7). The positive rates of DNMT3b protein expression were 56.3% (45/75), 26.7% (20/75), 46.4% (32/69) and 33.3% (23/69), respectively, which was highest in colorectal cancer tissue ( P <0.001), while without statistically significant difference from the precancerous tissue ( P >0.016 7). Experiments in vitro showed that DNMT3b mRNA expression was lowest in DNMT3b siRNA 30 nmol/L group among five groups and was statistically different from other groups (all P <0.05). Meanwhile, the methylationrate of SEPT9 gene was lowest in this group, but without statistically significant difference from the DNMT3b siRNA 15 nmol/L group ( P >0.05). Conclusions: The expression of DNMT3b is significantly correlated with the methylation level of SEPT9 gene in different stages of colorectal cancer. The high expression of DNMT3b may be an important molecular event before SEPT9 gene methylation and it may have an important potential application value in the diagnosis and treatment of early colorectal cancer.

Objective: To examine the outcome of off-pump coronary artery bypass (OPCAB) in elderly patients with left ventricular dysfunction. Methods: From June 2008 to July 2016, 252 patients aged over 80 years underwent isolated OPCAB at Department of Cardiovascular Surgery, Beijing Anzhen Hospital, Capital Medical University, these patients' data were collected. The left ventricular dysfunction group (ejection fraction (EF): 35% to 50%) was comprised of 31 patients aged (82.0±2.1) years (range: 80 to 88 years), including 25 males and 6 females. Through matching one-to-one on propensity scores, 31 patients (EF > 50%) were included into the left ventricular normal group. Among them, there were 25 males and 6 females, aged (81.9±1.9) years (range: 80 to 89 years). Postoperative mortality and complications between the matched groups were compared using the t test, Wilcoxon rank-sum test, χ(2) test or Fisher exact test. Results: Between the dysfunction group and normal group, the preoperative serum creatinine was 144.6(66.0) μmol/L vs . 94.9(43.2) μmol/L ( M ( Q(R) ), Z= 3.177, P= 0.033), respectively, while the pre-discharge serum creatinine was 147.0(59.0) μmol/L vs . 92.0(24.0) μmol/L ( Z= -2.685, P= 0.007), respectively. In dysfunction group, the perioperative intra-aortic balloon counterpulsation (IABP) utilization rate was higher (25.8%(8/31) vs . 3.2%(1/31), P= 0.026), the total hospitalization day was longer (17(15) days vs . 14(8)days, Z= 2.054, P= 0.012), the preoperative hospitalization day was longer too (7(7) days vs . 5(4) days, Z= -2.457, P= 0.014). However, there was no significant difference in the incidence of postoperative mortality (9.7%(3/31) vs . 3.2%(1/31), P= 0.612) and other prognostic indicators between the two groups. Conclusions: The elderly patients, with light and moderate left ventricular insufficiency, are characterized by the abnormal increase in renal function and the rise of IABP utilization due to hemodynamic disorder in OPCAB perioperative period. Preoperative treatment for cardiac insufficiency may be the cause of prolonged preoperative and total hospital stay. However, there is no significant difference in the postoperative mortality and other complications compared with the patients of normal left ventricular function.

Objective: To assess the efficacy and long-term outcome of percutaneous balloon aortic valvuloplasty (PBAV) for children with congenital aortic stenosis (CAS) and to explore risk factors for significant aortic regurgitation (AR) and reintervention after PBAV during follow up. Methods: This was a retrospective study. Children (≤18 years old) with CAS, who underwent PBAV in Guangdong Provincial Hospital from January 2004 to December 2018, were included in this study. Demographic, preoperative transthoracic echocardiography (TTE) and surgical data were collected. Postoperative complications were closely observed, and the patients were followed up at 1, 6, 12 months after the operation, and then at one year interval thereafter. Endpoint events included significant AR and reintervention. Reintervention was defined as any intervention that needed to be performed on the valve for various reasons, including re-PBAV, surgical valvuloplasty and valve replacement. Significant AR was defined as AR grade≥3 by TTE criteria. The results of the last TTE examination before the end of the study were collected. The Kaplan-Meier curve for long-term AR-free and intervention-free survival was plotted. Cox regression model was used to further analyze the risk factors for significant AR and reintervention after PBAV in CAS patients. Results: A total of 55 patients were enrolled in this study, and the age was 4.6(1.6, 6.5) years, with 37(67.3%) males. The peak systolic valve gradient fell from (80.3±30.6)mmHg to (38.5±18.5)mmHg( P <0.001, 1 mmHg=0.133 kPa). Surgical success rate was 89% (49/55). Acute post-PBAV AR occurred in 18 patients, including 3 patients with RA≥3 grade. In-hospital complications occurred in 6 patients (2 deaths, 2 cases of transient arrhythmia, and 2 cases of femoral artery embolization). Fifty patients accomplished the follow-up and the follow-up time was 6.2(3.4, 8.5) years. Significant AR was found in 20 patients. Significant AR-free survival rate was 53% at 5 years and 19% at 10 years. Reintervention was performed in 11 patients (4 with valvuloplasty and 7 with valve replacement), and the 5-year and 10-year intervention-free survival rates were 87% and 62%, respectively. Multivariate Cox regression analysis showed that acute post-PBAV AR was a risk factor for long-term significant AR ( HR =2.398, 95% CI 1.007-5.712, P =0.048). Post-PBAV residual pressure gradient ≥ 35 mmHg ( HR =4.747, 95% CI 1.116-19.329, P =0.030)and acute post-PBAV AR ( HR =5.104, 95% CI 1.083-24.065, P =0.039)were risk factors for re-intervention. Conclusions: PBAV is safe and effective in the treatment of CAS in children, but attention should be paid on significant AR post procedure. Acute post-PBAV AR is a risk factor for re-intervention and significant AR post PBAV, and high post-PBAV residual pressure gradient is a risk factor for re-intervention.

Objective: To understand the prevalence of soil-borne nematode infections among residents living in urban/town areas of China, so as to provide insights into the control and elimination of soil-borne nematodiasis., Methods: A total of 5 epidemic areas were classified in China according to the prevalence of human Clonorchis sinensis infections captured from the 2014-2015 national survey on major human parasitic diseases in China, and the total sample size was estimated according to the binomial distribution and Poisson's distribution. Then, the total sample size was allocated proportionally to each province (autonomous region, municipality) of China based on the percentage of residents living in urban and town areas, and the number of survey sites in each province (autonomous region, municipality) was proportionally assigned according to the percentages of residents living in urban and town areas. Then, stratified sampling was performed at county, township and community levels according to the number of sampling sites in each province (autonomous region, municipality), and the survey site (community) was defined as the smallest sampling unit. All permanent residents in the survey sites were selected as the study subjects, and their stool samples were collected for identification and counting of parasite egg using a Kato-Katz technique. The prevalence and intensity of each parasite species were calculated., Results: From 2014 to 2015, among the 133 231 residents detected in 31 provinces (autonomous regions, municipalities) of China, the overall prevalence of soil-borne nematode infections was 1.23% (1 636/133 231), and the prevalence rates of hookworm, Ascaris lumbricoides and Trichuris trichiura infections were 0.77% (1 032/133 231), 0.32% (426/133 231) and 0.17% (224/133 231), respectively. The highest prevalence of soil-borne nematode infections was seen in Jiangxi (4.03%, 82/2 034) and Chongqing (4.03%, 524/13 012), followed by in Hainan (3.47%, 72/2 075). The prevalence of soilborne nematode infections was 1.07% (662/62 139) in men and 1.37% (974/71 092) in women, and the greatest prevalence was found in residents at ages of 65 to 70 years (2.56%, 219/8 569). With regard to occupations and education levels, herdsmen (2.47%, 2/81) and illiterate residents (3.33%, 226/6 795) were found to have the highest prevalence of soil-borne nematode infections, respectively. In addition, mild infections were predominantly identified in hookworm-, A. lumbricoides - and T. trichiura -infected individuals (all > 90%)., Conclusions: The overall prevalence of soil-borne nematodiasis remains low in urban and town areas of China; however, human infections are widespread. According to the epidemiological features, health education combined with deworming are recommended to reduce the prevalence of soil-borne nematode infections among residents living in urban and town areas of China.

Objective: To detect pathological variant in two patients with Chediak-Higashi syndrome (CHS) from a consanguineous family and to explore its genotype-phenotype correlation., Methods: Clinical data was collected for this pedigree. Genomic DNA was prepared from probands' peripheral leukocytes and their relatives' fingernail. Whole exome sequencing and Sanger sequencing were carried out to detect potential variant of the LYST gene., Results: The proband presented with partial oculocutaneous albinism, immunodeficiency and acidophilic inclusion body in bone marrow and blood smears. A novel homozygous nonsense variant c.8782C>T (p.Gln2928*) was identified in exon 34 of the LYST gene in the sib pair. The same variant was found to be in heterozygous status in 6 unaffected individuals from the pedigree., Conclusion: Above result enriched the mutational spectrum of CHS and provided a basis for genetic counseling and prenatal diagnosis for this pedigree.

Objective: To understand the epidemic status of Enterobius vermicularis infections among children aged 3 to 9 years in China, so as to provide scientific basis for the formulation of the prevention and control strategies for enterobiasis., Methods: The national surveillance of enterobiasis was performed in 736 national surveillance sites (counties) from 30 provinces (municipalities/autonomous regions) in China from 2016 to 2018. All surveillance sites were classified into parts according to the geographical directions, including the eastern, western, southern, northern and middle parts, and a township was randomly selected from each part. Then, an administrative village was randomly selected from the township, and 200 permanent residents at ages of over 3 years living in the administrative village were randomly selected using the cluster sampling method. A total of 1 000 residents were examined in each surveillance site. E. vermicularis infections were detected among children at ages of 3 to 9 years using the modified Kato-Katz technique and the adhesive cellophane-tape perianal swab method, and the prevalence of infections was calculated and compared., Results: The prevalence of E. vermicularis infections was 2.50%, 2.84% and 2.46% among children at ages of 3 to 9 years in the 736 surveillance sites from 30 provinces (municipalities/autonomous regions) in China from 2016 to 2018, and there was no gender-specific prevalence of E. vermicularis infections ( P > 0.05). Enterobiasis was main prevalent in the southern and southwestern part of China (Jiangxi, Guangxi, Guangdong, Sichuan, Fujian, Chongqing and Hainan), with 5.00% prevalence and greater, and the highest prevalence was seen in Jiangxi and Guangxi for successive 3 years. In addition, the prevalence of E. vermicularis infections was higher in children with the Han ethnicity than in those with the minority ethnicity, and a high prevalence was found in children at ages of 4 to 7 years, and a low prevalence seen in children at ages of 3, 8 and 9 years., Conclusions: The prevalences of E. vermicularis infections have not changed much among children at ages of 3 to 9 years in China from 2016 to 2018, and high prevalence is seen in southern and southwestern China, which should be given a high priority.

Objective: To establish an evaluation system for the field assessment of the Kato-Katz technique in detecting soiltransmitted nematodes, so as to provide insights into the field application of the Kato-Katz technique., Methods: The initial evaluation indicators were determined through literature search, brainstorming and expert consultation. The evaluation indicatorswere improved and the weight of each indicator was decided through three rounds of expert consultation by using the Delphimethod. In addition, the expert authority coefficient and the coordination coefficient of each indicator were calculated at eachround of expert consultations., Results: The recovery rates of the questionnaire were 100.00%, 100.00% and 89.29% at the firstto the third round of the expert consultations, respectively, and the expert authority coefficients were all more than 0.85 at eachround. The final evaluation system included 4 first-level indicators and 15 second-level indicators. In the first-level indicators, "detecting effect" and "funds investment" had the mean weighted value of 4.53 and 4.49, which were relatively higher than that of"person-time investment" and "operability" (both 4.34). Among the second-level indicators under each first-level indicator, thefour most significant indicators included "ability of personnel in egg discrimination", "cooperation of village cadres and doctors","Person-time on testing" and "organizational start-up cost", with the mean weighted values of 4.74, 4.43, 4.39 and 4.17, respectively. The coordination coefficients were 0.39 to 0.65, 0.28 to 0.58 and 0.45 to 0.65 at the first to the third round of the expertconsultations, respectively, and there were significant differences in the coordination coefficients at all three rounds of the consultations (all P < 0.05)., Conclusions: An evaluation system for the field assessment of the Kato-Katz technique in detecting soiltransmitted nematodes is successfully established, among which "ability of personnel in egg discrimination" and "cooperation ofvillage cadres and doctors" have the greatest mean weighted values of the significance.