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Background The prevalence of hypertension among Chinese residents is high while the control rate is low. It has been suggested by numerous epidemiologic studies that reducing salt intake could reduce blood pressure level. Therefore, it is significant for health management of residents and reducing social burden to explore determinants of salt-reduction behavior among residents. Objective To explore the predisposing, reinforcing and enabling factors of salt-reduction behavior among Shandong residents based on the PRECEDE model, and provide scientific suggestions for the subsequent salt-reduction campaign. Methods This study was a mixed methods research. A total of 114 residents were interviewed in 2016 and 2018 by using purposive sampling method. The interview guide mainly contained attitudes to salt control, difficulties encountered and assistance received during salt control. The quantitative data were obtained from the database of terminal survey of Shandong and Ministry of Health Action on Salt and Hypertension (SMASH), and the sample of eastern as well as central-southern Shandong from the database was selected into this research. The part related to hypertension among this survey was selected from the database, and a total of 6 697 research objects were finally selected. Results The results of multinomial Logistic regression showed that gender, occupation and education level have an impact on the compliance of salt reduction behavior controlling for the effect of other variables (P

When faults such as blocking and commutation failure occur in a high-voltage direct current （HVDC） transmission system， they can cause transient voltage fluctuations near the sending-side converter station and lead to the disconnection with power grid. Firstly， the operating principles， response characteristics， and key parameter influences of the grid-forming energy storage open-loop control strategy are analyzed. Then， the reactive response characteristics of the synchronous condenser are analyzed， and a comparison is made between the grid-forming energy storage reactive power control model and the excitation regulation control model. Finally， a semi-physical simulation system is established， including EHVDC， photovoltaics， synchronous condenser， and grid-forming energy storage， to conduct comparative experiments on the effect of suppressing AC transient overvoltage under DC commutation failure. The results indicate that grid-forming energy storage and distributed synchronous condenser with the same capacity can achieve similar effects in terms of reactive transient response speed and the ability to suppress AC transient overvoltage.

Deep learning methods based on time series prediction are widely applied to solving fluid dynamics problems. However, the application characteristics of Long Short-Term Memory (LSTM) and Gate Recurrent Unit (GRU) in fluid mechanics are lacking in the existing research. Therefore, this paper proposes two flow field prediction models combining the Proper Orthogonal Decomposition (POD) method, referred to as POD-LSTM and POD-GRU. Their performance in flow field prediction is compared with numerical simulation data and experimental data respectively. The numerical simulation was obtained by using OpenFOAM-v9, and the experimental data were obtained from Particle Image Velocimetry (PIV). The results show that LSTM performs excellently in predicting velocity field, while GRU excels in predicting pressure field. On the other hand, under the same computational resources and cost, the training time required by GRU is shorter than that of LSTM. Furthermore, as the number of POD modes increases, the overall deviation of LSTM network predictions from actual flow field values tends to increase. In contrast, GRU networks show the opposite trend. This study provides a detailed description of the performance of POD-LSTM and POD-GRU in fluid mechanics. The proposed prediction models demonstrate strong generalization capabilities, further exploring the potential of deep learning methods in fluid mechanics.

The content of ethanol in wine can affect its quality. Some edible alcohol contains small amounts of methanol, and its accumulation can cause serious health problems. Therefore, it is very important to test the contents of methanol and ethanol in alcohol products. In this paper, a rapid method for the determination of methanol and ethanol by ambient corona discharge ionization mass spectrometry was developed. The method is based on the interaction of water radical cation with methanol and ethanol, respectively. In the positive ion mode, the water dimer radical cation (H2O)2+· (m/z 36) with ambient corona discharge ionization source was prepared by using ambient corona discharge ionization source, and it was introduced into the mass spectrometer with methanol or ethanol through a dual-channel low-energy corona discharge ionization device. The two reacted with each other to form the corresponding water radical cationic complex [CH3OH+H2O]+· (m/z 50) and [CH3CH2OH+H2O]+· (m/z 64), which realized the direct and rapid qualitative and quantitative analysis of methyl alcohol and ethanol in different kinds of alcoholic beverages. The result showed that the limits of detection and the limits of quantification of methanol and ethanol were 0.011 and 0.004 mg/L, 0.038 and 0.014 mg/L, respectively. The correlation coefficients of the target ionic strength curves obtained by the interaction of different concentrations of standard methanol and ethanol with water free radical cation could reach to 0.990 4 and 0.991 1, respectively. By using this method, no methanol was detected in common alcoholic drinks, and the ethanol content in liquor was higher than beer. In the actual work, the method has good practicability through the experimental exploration and verification of different wines. This method does not require sample pretreatment, has the advantages of simple operation and fast analysis, and is especially suitable for the detection of aqueous system. This study has important guiding significance for the quantitative detection and analysis of methanol and ethanol in complex system, provides technical support for the detection of alcoholic beverages and food, and also provides an effective strategy for the quantitative detection of the content of small and medium molecular alcohols in actual samples.

Microdroplets have many unique features such as small size and high electric field, therefore they can be accelerated to initiate chemical reactions and even promote some reactions that cannot be carried out in liquid phase. N, N-Dimethylaniline (DMA) is commonly used in medicine as a raw material for the synthesis of pharmaceutical intermediates. At present, the study involving in the detection of DMA is mainly focused on quantitative detection, and there is few reports on oxidation reaction and gas phase dissociation reaction of DMA. In this paper, the oxidation behavior and dissociation reaction of DMA and related compounds were studied by microdroplet spray mass spectrometry and tandem mass spectrometry. It was found that the ultra-high electric field spontaneously generated by microdroplets at the air-water interface can enable the oxidation reaction of DMA and related compounds to form abundant radical cation DMA+·. By changing the reaction distance, carrier gas pressure, injection velocity, sample concentration and substituent groups, the influence of experimental conditions and substituent modes on the generation of DMA+· was explored. The result showed that the presence of electron donor groups is benefit for the stability of radical cations. After the dissociation of DMA+·, the main product ions were generated by elimination of hydrogen radical and a successive elimination of HC≡N via methyl migration reaction. In addition, when the electron-donating CH3 group was connected with DMA, the intensity of related radical cation increased obviously, indicating that the electron-donating groups promoted the migration reaction. In conclusion, the stable transient intermediate DMA+· that is difficult to prepare by other means, was obtained by microdroplet reaction in this study. This method is helpful to deepen the understanding of the chemical promoted oxidation reaction characteristics of water droplets and enriches the rearrangement reaction types of aniline compounds in gas phase dissociation. It is expected that the prepared active species such as high reactivity radical cations will be applied to chemical industry or pharmaceutical fields in the future.

According to a small-step real-time simulation study on active neutral-point clamped （ANPC） three-level converters， existing electromagnetic transient modeling methods are inferior in model accuracy， computational efficiency， simulation scale， etc. To this end， an efficient electromagnetic transient simulation model is proposed. The model is built based on the associated discrete circuit （ADC） of the ANPC three-level bridge arm， and the internal nodes are eliminated by the WARD equivalence theory to construct an externally equivalent multi-port Norton equivalent circuit that replaces the bridge arm for solving the electromagnetic transient simulation of the network and achieving node reduction and simulation acceleration without spoiling modeling accuracy. A simulation system of the ANPC three-level converters based on this equivalent model is built in MATLAB/Simulink platform. Compared with the detailed model simulation results， the equivalent model can accurately simulate the steady-state and transient operating conditions and significantly accelerate the simulation.

The low-permeability reservoir is one of the important oil production positions in Shengli Oilfield， and its reserves accounts for more than 20% of the total oilfield reserves. The low-permeability reservoir always presents characteristics such as a narrow pore throat and strong heterogeneity， which results in high injection pressure and difficult injection during water flooding. At present， the main measures to improve the development effect include active agents for reducing pressure and increasing injection， water injection under high pressure， and narrowing the distance of drainage wells. However， there are still some production problems， such as short effective time， low well injection per well， low liquid production per well， and small swept volume. Therefore， it is urgent to develop new and efficient development methods. Since the “13th Five-Year Plan in 2016-2020”， the synergistic development modes have been implemented， such as replenishing energy injection enhancement in injectors， increasing production by imbibition in producers， and increasing swept volume by displacement between injectors and producers， which can enhance displacement pressure gradient， water displacement， and recovery. The synergistic development mode has been applied in Chunhua Oilfield. The injection pressure of the well in 62 Block of Chunhua Oilfield has been reduced by 20%； the water injection has been increased by 25%， and the daily oil production of the single production well has increased from 0.45 t/d to 5.08 t/d， with obvious yield increase benefit. The overall recovery has increased by more than 8%.

In order to improve the mechanical properties of PBO fiber wet-laid forming mesh, the hot pressing process was used to strengthen it, and the Box-Behnken response surface method was used to establish a response surface model by taking three factors of hot pressing temperature, hot pressing pressure and hot pressing time as independent variables, and taking the fracture strength of PBO fiber wet-laid nonwoven materials as the response value. The results show that the established response surface model is significant and has good fit. The Box-Behnken response surface method can predict the fracture strength of PBO fiber wet-laid nonwoven materials, and conclude that the factors affecting the fracture strength of PBO fiber wet-laid nonwoven materials are hot pressing pressure > hot pressing temperature > hot pressing time. The optimize process parameters of hot pressing are hot pressing temperature 245.6 ℃, hot pressing pressure 8.4 MPa, and hot pressing time 9.3 min. The average breaking strength of PBO fiber wet-laid nonwoven material obtained under this process parameter is 393.9 N.

The emergence of ChatGPT (Chat Generative Pre-trained Transformer) has created new opportunities and challenges in the field of education. This paper explores the usage of ChatGPT to improve learning efficiency, teaching effectiveness, and educational efficiency in pharmacology instruction. The study evaluated the usage of ChatGPT across three stages of pharmacology coursework: pre-class preparation, post-class extension, and evaluation, through comparison with conventional settings in these stages. Generative artificial intelligence can be used as a virtual teaching assistant and learning aid. It can be used to transform learning styles across the above three stages to focus on cultivating critical and creative thinking in students. ChatGPT can play a leading role in teaching, and help better balance the relationship between education and artificial intelligence. However, we need to clarify the status of ChatGPT as a tool and prevent over-reliance on it.

Although traditional quantum-confined nanostructures e.g. regular quantum wells or quantum dots have achieved huge success in the field of semiconductor lasers for past decades, these traditional nanostructures are encountering the difficulty of enhancing device performance to a higher level due to their inherent gain bottleneck. In this paper, we are proposing a new super-gain nanostructure based on self-assembled well-wire complex energy-band engineering with InGaAs-based materials to break through the existing bottleneck. The nanostructure is constructed by utilizing the special strain-driven indium (In)-segregation and the growth orientation-dependent on-GaAs multi-atomic step effects to achieve the distinguished ultra-wide and uniform super-gain spectra. The structural details and its luminescence mechanism are investigated by multiple measurement means and theoretical modeling. The polarized gain spectra with the max fluctuation of

ObjectiveTo investigate the quality of disinfection in the SARS-CoV-2 nucleic acid sampling sites in Shanghai.MethodsSwab samples of medical staff’ hands and environments of different SARS-CoV-2 nucleic acid sampling sites were collected from July to September 2022， with the total number of bacterial colonies cultured and counted.ResultsA total of 728 swab samples were collected from 69 sampling sites. The median total number of bacterial colonies on hand surface， object surface and air samples were 0 CFU·cm-2， 0 CFU·cm-2， and 1 CFU·（petri dish∙5 min）-1， respectively， and P95 was 13 CFU·cm-2， 5.3 CFU·cm-2， and 17.8 CFU·（culture vessel∙5 min）-1， respectively. According to the GB 15982‒2012 Hygienic Standard for Disinfection in Hospitals class Ⅳ environment， 680 samples met the standard （93.4%）. Furthermore， 96.9%， 92.0%， and 92.2% of the samples in the sampling sites of tertiary/secondary hospitals， community health centers， and community convenience sampling sites met the standard， respectively. Quality of disinfection did not differ significantly across these sampling sites.ConclusionThe quality of disinfection in the SARS-CoV-2 nucleic acid sampling sites in Shanghai is generally good. Additionally， hand hygiene of medical staff and disinfection on object surface in some sampling sites need to be strengthened.

ObjectiveThis study aimed to investigate the risk factors affecting the positive detection of Acinetobacter baumannii on the hands in medical staff of hospitals in Shanghai， and provide epidemiological evidence for the prevention and control of nosocomial infections.MethodsThe hands of doctors， nurses and care workers in key departments were sampled every quarter from 2018 to 2020 according to GB 15982‒2012 "Hospital Disinfection and Hygiene Standards". Separation and identification of A. baumannii were followed with sampling shortly. Information about the working years of sampling subjects， the hand sanitizers of which sampling subjects had used and the ingredients and actual using time of the hand sanitizers was collected while sampling. Finally， 709 samples were selected for this research after excluding the unqualified samples.ResultsThe positive detection of the hand samples was 7.05%. The logistic regression model suggested that the department， the time of using hand sanitizer， the hospital grade and occupational category were determinants of A. baumannii positive detection on hands in medical staff. The risk of A. baumannii positive detection in internal medicine department was 2.846 （95%CI：1.402‒5.776） times higher than that in intensive care unit while it was 3.357 （95%CI：1.349‒8.353） times higher in surgery department than that in intensive care unit. Regarding the use of hand sanitizer， the risk of A. baumannii positive detection was 3.076 （95%CI：1.534‒6.168） times higher in the staff used the hand sanitizer over 14 days than in the medical staff used the sanitizer within 14 days. The risk of A. baumannii positive detection in medical worker in secondary hospitals was 2.235（95%CI：1.088‒4.588）times than in tertiary hospitals. The risk of A. baumannii positive detection of care workers was 3.634 （95%CI：1.764‒7.484） times higher than nurses.ConclusionThe positive detection of hand samples was 7.05%. Department， the time of using hand sanitizer， the hospital grade and occupational category were determinants of A. baumannii positive detection on hands in medical staff. It was necessary to improve hand hygiene for medical staff， especially for care worker. Cleaning and disinfection need to be strengthened in internal department and surgery department.

Corn starch was modified by dry heat treatment combined with amino acids (aspartic acid and lysine) in the present research. Gelatinization, thermal, structural, and digestive properties of dry heat-treated corn starch with different amount of amino acids were investigated by using Rapid Viscosity Analyser, differential scanning calorimetry, and X-ray diffractometry. The results indicated that the amount of amino acids showed significant effects on the physicochemical properties and digestive properties of dry heat-treated corn starch-amino acid mixtures. With increasing the addition of amino acids, peak viscosity, setback value, and gelatinization enthalpy of starch decreased, while relative crystallinity and resistant starch content increased. Gelatinization temperature of dry heat-treated corn starch-aspartic acid mixtures showed a tendency to increase first and then decrease with increasing the amount of aspartic acid. However, gelatinization temperature of dry heat-treated corn starch-lysine mixtures increased with increasing the amount of lysine. Increasing the amount of amino acids also promoted a tighter and more ordered crystal arrangement inside starch granules, which could inhibit the short-term retrogradation and reduce the digestibility of starch. This study can be used as a new method for corn starch modification and provide a reference for the production of modified starch.

Seagrass ecosystems capture and store a large amount of carbon every year. However, co-mpared with other ecosystems, research on deep sediment carbon pools in China 's seagrass ecosystem is still relatively scarce. In this study, a total of 24 deep sediment samples were collected, with a total of 264 subsediment samples. The distribution of organic carbon content in sediments at 0~60 cm in Caofei-dian seagrass bed in China were analysed. The organic carbon content in sediments ranged from 0.080% to 1.004%, the average organic carbon content was 0.456%, and the median value ranged from 0.170% to 0.740%. The collection of samples followed the principle of typicality and representativeness, and the Caofeidian seagrass bed in China was sampled and investigated. Sediment physical and chemical pr-operties are important factors affecting the content of organic carbon in sediments. There was a significant negative correlation between organic carbon content and bulk density, a significant positive correlation with water content, a positive correlation with TN, and no correlation with TP.

The loess was stabilized using geopolymer (GP). Triaxial compression tests were conducted on stabilized loess with varied GP contents subjected to wet–dry cycles. The degradation law of the shear strength of the stabilized loess after varied wet–dry cycles was evaluated and an empirical model for predicting the shear strength was proposed. The chemical composition of the hydration products, the microstructure and pore size distribution of stabilized loess were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and mercury intrusion porosimetry (MIP) tests. The degradation mechanisms of GP stabilized loess under wet–dry cycles were discussed based on the experimental results. The experimental results show that compared with untreated soil, the shear strength of stabilized soils is significantly improved with the increasing GP content, i.e. the cohesion and internal friction angle increase by 260% and 43%, respectively. The shear strength of stabilized loess decreases with the increasing ratio of porosity to GP volumetric fraction ( ) in a power function. It indicates that GP stabilization can remarkably improve the durability of loess under wet–dry cycles. The stabilized loess with 10% and 15% GP can maintain over 75% of their original shear strength, but those with 5% GP shows evident deterioration in shear strength after nine wet–dry cycles. The wet–dry cycling has greater impact on the degradation of peak deviatoric stress and cohesion than that of internal friction angle. An empirical model was proposed and validated for predicting the degradation in shear strength of the GP stabilized loess under wet–dry cycles, considering influence of the GP content, confining pressure and the number of wet–dry cycle. The experimental results of XRD, SEM and MIP show that the main hydration products of GP are calcium silicate hydrate (CSH) and calcium aluminosilicate hydrate (CASH), which fill the soil pores and enhance the bonding between soil particles. Due to this reason, a denser microstructure develops and the cohesion of the stabilized loess increases, which consequently improves the shear strength of the GP stabilized loesses. Moreover, the wet–dry cycle results in the expansion of soil pores and the formation of new fissures, which destructs the bonding between soil particles and reduces the shear strength of the stabilized loess.

C22H20O4, orthorhombic, P212121 (no. 19), a = 11.355(5) Å, b = 15.084(7) Å, c = 20.078(9) Å, V = 3439(3) Å3, Z = 4, Rgt(F) = 0.0382, wRref(F2) = 0.0994, T = 296(2) K.

Abstract Intersubband (intraband) transitions allow absorption of photons in the infrared spectral regime, which is essential for IR-photodetector and optical communication applications. Among various technologies, nanodisks embedded in nanowires offer a unique opportunity to be utilized in intraband devices due to the ease of tuning the fundamental parameters such as strain distribution, band energy, and confinement of the active region. Here, we show the transverse electric polarized intraband absorption using InGaN/GaN nanodisks cladded by AlGaN. Fourier transform infrared reflection (FTIR) measurement confirms absorption of normal incident in-plane transverse electric polarized photons in the mid-IR regime (wavelength of ~ 15 μm) at room temperature. The momentum matrix of the nanodisk energy states indicates electron transition from the ground state s into the p x or p y orbital-like excited states. Furthermore, the absorption characteristics depending on the indium composition and nanowire diameter exhibits tunability of the intraband absorption spectra within the nanodisks. We believe nanodisks embedded nanowires is a promising technology for achieving tunable detection of photons in the IR spectrum.

During the active alignment focusing process of car camera assembly, lenses and holders need to be gummed by creamy white and translucent UV glue. The quality of glue dispensing can directly influence the performance of car cameras. Because of the translucency of UV glue, the glue dispensing image may present a low contrast situation, which increases the difficulty of vision detection. This paper proposes a method based on CycleGAN to enhance the glue dispensing image and effectively overcome the problems of blurred and low contrast edges. First, the glue part of the image is segmented into twenty regions. Second, the VGG16 model is used to divide the abovementioned twenty regions into high-contrast images and low-contrast images. Next, the CycleGAN model is trained to enhance the low-contrast images, and then convert them to high-contrast images. Finally, glue contours are extracted by using thresholding segmentation and edge detection to ensure that the quality of glue dispensing can be detected. The success rates of the VGG16 model and the CycleGAN model are 96% and 58%, respectively. The results show that the proposed method can effectively enhance the low contrast part of the glue region and improve the detection accuracy. Specifically, it can increase the gray value difference between the glue and the background from 20 to 55, while the background is substantially retained. The detailed information of the edges of the images is enriched. The accuracy of glue edge extraction can be increased to 99%, which is an approximately 75% improvement compared to the methods without enhancement.

The study takes the high RS (resistant starch) rice and common rice as raw materials to produce instant rice products, so as to study the effects of high RS rice content in instant rice products on their texture features, flavor scores and GI. By analyzing the texture features and differential scanning calorimeter of instant rice products, the effects of high RS rice content in instant rice products on returning raw with different storage time are also studied. The results show higher proportion of high RS rice in products increase the hardness, viscosity, chewiness of instant rice products, as well as the amylose and resistant starch.However, the flavor evaluation and GI decreases. In addition, as the storage time increases, the higher the amount of high-RS rice added, the higher the hardness, relative crystallinity, and enthalpy of recovery of the instant rice products. This paper hopes to provide theoretical support for the development of instant rice products and deep processing of rice.

Objective: To solve the problems of low whole rate of the tobacco shredded from the cabinet, high rate of broken shreds and high concentration of regional dust. Methods: A flexible feeding and discharging system of the wire storage cabinet was designed, which effectively reduced the shredded tobacco and the regional dust concentration through the automatic telescopic sliding plate and the sliding and lifting raking roller. Results: After adopting the flexible feeding and discharging system of the wire storage cabinet, the change rate of the whole wire rate increased by 1.1%, from 80.2% to 81.1%, and the broken wire rate decreased to 2.2%; The regional dust concentration C-TWA decreased to 0.5 mg/m3. Conclusion: The improved wire storage cabinet achieves the purpose of cleaner production, cost reduction and efficiency enhancement.

The market common rice was used to make fresh and wet convenient rice in this study.The effects of soaking time, soaking temperature, cooking temperature, cooking time and cooking pressure on the quality of fresh and wet convenient rice were studied.Moreover, the effects of different concentration of fructo-oligosaccharides on texture and sensory score were studied on the fresh and wet convenient rice.And the effects of different amounts of fructo oligosaccharides on hardness, viscosity, sensory score and enthalpy on fresh and wet convenient rice were also studied under different storage time.The results showed that the optimum soaking temperature was 45 ℃ and the soaking time was 60 min.Through orthogonal test, the optimum cooking process of fresh and wet convenient rice was determined as follows: the cooking pressure was 0.25 Mpa, the cooking time was 30 min, and the water ratio of cooking rice was 1∶0.9.When oligosaccharides was added to 1.5% of fresh and wet convenient rice, it had obvious anti-aging effect and the highest sensory score.

In addition to direct solar illumination to the photovoltaic cell, the albedo effect provides a unique opportunity to enhance energy harvesting. However, conventional solar cells are inefficient albedo energy harvesters because the rear side of the cell is usually blocked by a thick substrate or metal contact. In this study, structurally thin active layers of GaAs thin‐film solar cells covered with transparent Ag nanowires that enable bifacial solar cell operations are fabricated. The GaAs bifacial thin‐film solar cell is fabricated by bonding the active regions of the solar cell on colorless polyimide sheets with highly transparent epoxy adhesives. The fabricated bifacial solar cells without any anti‐reflection coatings demonstrated power conversion efficiencies of 8.54 and 6.78% at the front and rear sides, respectively, under AM 1.5 G irradiance conditions. The increase in energy harvesting by the GaAs bifacial thin‐film solar cells was estimated, which showed approximately a 72% increase in short‐circuit current density (JSC) when the solar cells operated on a high‐reflection‐coated ground. Positioning the solar cells on snow or sand (deserts and beaches) increased JSC by ≈44 and 31%, respectively, compared to monofacial solar cells.

Objective To conduct bibliometric analysis of forensic genetics literatures published by Chinese mainland scholars in SCIE journals from 1989 to 2019, to show the research achievements of the past three decades and predict future research fields and directions. Methods Microsoft Office Excel 2019 was utilized to analyze the general situation, research institutions, authors, funds, author keywords, etc. of the literatures. The status of research in forensic genetics in Chinese mainland was visualized by PlotDB, Gephi 0.9.2 software and literature interpretation. Results During the last three decades, 1 126 forensic genetics literatures were published by scholars from Chinese mainland on SCIE journals, mostly articles. The quantity and quality of the literatures were both on the increase. The number of literatures published in Forensic Science International-Genetics was the highest, and 60.83% of the literatures were funded, mainly by the National Natural Science Foundation of China （498 literatures）. The current research hotspots were STR, SNP, InDel polymorphisms, linkage genetic markers, mtDNA genetic markers, epigenetic markers, RNA genetic markers, chip technology and omics research method. Conclusion The forensic genetics in China has developed rapidly along with the promotion of forensic science in universities. The SCIE literatures on forensic genetics published by Chinese mainland scholars increased rapidly with the funding from the National Natural Science Foundation of China and Ministry of Science and Technology of the People’s Republic of China, which positively contributes to the development of basic research and the improvement of overall level in forensic genetics in China.

In order to improving the drying property and quality of non - fried extruded potato instant noodles,the drying characteristics of non-fried extruded instant noodles with diametral of 0.7 mm,1mm and 1.2 mm under the conditions of 40 ℃,50 ℃,60 ℃ and 70 ℃ were studied respectively.On this basis,an optimal drying kinetic model was established.The result showed that the drying stage of instant noodles mainly belonged to the speed reduction stage,and the noodle diameter and drying temperature had a great influence on its characteristics.Page model can express and predict the variation of moisture ratio (MR) with drying temperature (T) at any time of instant noodle drying.The effective water diffusion coefficient of instant noodles was between 0.463×10-9 m2/s and 1.845×10-9 m2/s.The drying activation energy of instant noodles with diameter of 0.7 mm and 1mm was 47.904 kJ/mol and 65.265 kJ/mol respectively.Properly reducing the noodle diameter can effectively reduce the energy loss in the drying process.This study provides data support for equipment selection,energy saving and consumption reduction and industrial design of non-fried extruded potato instant noodles drying process.

In order to improve the existing issues of bamboo shoot parfait such as the stiffness and lack of elasticity, taking sensory score as index, the effects of sodium bicarbonate, citric acid, single octylic acid glyceride, compound phosphate and sorbitol on the quality of bamboo shoots foam were studied by single factor test and orthogonal test. The experimental results showed that: When the addition of sodium bicarbonate, citric acid, monocaprylic glyceride, compound phosphate and sorbitol were at 0.15%, 0.02%,0.04%, 0.4% and 0.3% respectively, the bamboo shoot parfait was soft and elastic, and the sensory score reached 96.21 points. On this basis, the texture properties of the bamboo shoots parfait can be compared with those of the market samples. The texture properties of the bamboo shoots parfait were measured as follows:hardness 94.2, elasticity 0.92, chewability 711.51, viscosity 90.23, adhesion 537.79, which were similar to the texture properties of the market products.

In order to study the influence of the two-stage extrusion process on the quality of instant rice noodle, the key parameters of the two-stage extrusion process including: the first and second stage extruder barrel temperature, the first and second stage extruder screw speed, feeding speed, and the template hole diameter were taken as the single factor research objects, and the single factor experiment and response surface experiment were used to optimize them. The results show that the optimization of extrusion parameters can improve the quality of instant rice noodle in a certain range. The final optimization of the two-stage extrusion process parameters are as follows: the first stage extruder barrel temperature was 173 ℃,the second stage extruder barrel temperature was 39 ℃, the first stage extruder screw speed was 30 Hz, the second stage extruder screw speed was 20 Hz, the feeding speed was 11.8hz, and the template aperture was 0.7 mm. Under this condition, the instant rice noodle product is made with Strong fragrance and good comprehensive quality which can reach market product quality. This study can provide a reference for the continuous production of instant rice noodle.

Whole potato flour has high nutritional value, but it is limited in the processing of vermicelli because it cannot form a good gluten structure. In this study, single factor test and double factor test were used to optimize the vacuum and noodles process of whole potato flour noodle. The results showed that the water content had the greatest influence on the overall quality of whole potato flour, followed by the mixing time, the vacuum degree and rotation speed had little influence. The optimum parameters are 36% water addition, 12 minutes mixing time, 0.06 MPa vacuum degree and 60 R/min rotating speed. It provides practical data support for further industrial production of high proportion potato noodle products.

Objective To investigate the clinicopathological features and survival rate of oral squamous cell carcinoma patients in China. Methods The clinicopathological characteristics, stage, treatment modality, and 5-year disease-specific survival (DSS) rate of 1 915 OCSCC patients who received initial treatment at the Sun Yat-sen University Cancer Center from 1990 to 2013 were collected and analyzed. The clinicopathological characteristics, stage, treatment modality, and 5-year disease-specific survival (DSS) rate of OCSCC patients treated during the successive decades of 1990-1999, 2000-2009, and 2010-2013 were analyzed retrospectively to show the trends over time. Results The average age of all OCSCC patients who received initial treatment at this cancer center from 1990 to 2013 was 54.8 years (SD, 12.6 years). The sex ratio was approximately 2:1. The oral tongue was the site most prone for OCSCC, accounting for 63.6% of all cases. The proportions of early-stage (Ⅰ-Ⅱ) and advanced-stage (Ⅲ-Ⅳ) cases were approximate. Regarding the treatment modality, surgery-based treatment accounted for 80.4%. Survival analysis showed that the 5-year DSS rate of all cases was 57%. Survival decreased with age. The survival of females, nonsmokers, and nondrinkers was higher than that of males, smokers, and drinkers. The 5-year DSS rates of patients with squamous cell carcinoma of the lips, oral tongue, and other sites of the oral cavity were 81%, 63%, and 42%, respectively. The 5-year DSS rates of patients who received surgery-based treatment and nonsurgical treatment were 66% and 19%, respectively. The analysis of trends over time showed that in the period of 1990-1999 and 2010-2013, the age and sex ratio were relatively stable. The proportion of patients with squamous cell carcinoma of the lips and oral tongue gradually decreased, while the proportion of those with squamous cell carcinoma of the other sites of the oral cavity gradually increased. The proportion of surgery-based treatment increased from 77.7% to 91.3%. The 5-year DSS rate gradually increased from 53% in 1990-1999 to 64% in 2010-2013. The 5-year DSS rate of female patients increased significantly from 55% to 78%. However, the 5-year DSS rate of male patients was relatively stable. The 5-year DSS rate of patients who received surgery-based treatment gradually increased from 62% to 69%. Conclusion The 5-year DSS rate has steadily improved for OCSCC patients at this cancer center from 1990-2013, especially in female patients. The 5-year DSS rate of patients with squamous cell carcinoma of the oral tongue has reached the rate in developed countries worldwide. The proportion and survival rate of patients who received surgery-based treatment gradually increased. The survival rate of patients with squamous cell carcinoma of the other sites of the oral cavity was significantly lower than that of patients with squamous cell carcinoma of the lips and oral tongue, suggesting that more effort should be put into the treatment of patients with squamous cell carcinoma of the other sites of the oral cavity to improve the survival rate in the future.

As one of the main food crops in the world, the rice quality and safety situation is not optimistic, the development of rice traceability system has become a hot topic at home and abroad. This paper summarizes the research status of rice traceability technology from two aspects including the origin diagnosis technology (such as: physical index fingerprint technology, stable isotope technology, multi-element analysis technology, near-infrared spectroscopy technology) and the traceability system technology (such as: physical identification technology, information coding technology, information transmission technology). Based on this analysis, the development trend of rice traceability system was analyzed, and new technologies will continue to be applied to the traceability system.

Glycemic Index, proposed by Dr.Jekins in 1970, was an index that measured blood sugar capacity of food. Recent research indicated that glycemic index had positive effects on therapy of diabetic patients and weight management for the overweight. In this paper, the author introduced the concept of glycemic index, food materials grading based on GI, the relationships between GI and food components, the physiological reaction of human separately consuming high GI or low GI food, the application of GI in prevention and cure of diabetes. The review will provided scientific evidences for medical treatment and designing nutritional meal for diabetic patients in comtemporary medical science.

Fresh and wet rice noodles are the traditional staple food of rice products in south China, which contain high moisture, therefore it is difficult to ensure the quality during processing.The effects of different addition quantities of the four quality improvers on the quality of fresh and wet rice noodles were compared with potato modified starch, sodium pyrophosphate, lecithin and sodium alginate as quality improvers, and the cooking loss rate and sensory evaluation of fresh and wet rice noodles as indicators.On this basis,orthogonal tests were designed, and it was found that when adding 5% modified potato starch (dry matter mass fraction, the same below), 0.4% sodium pyrophosphate, 0.4% lecithin and 0.3% sodium alginate, the cooking loss rate of fresh and wet rice noodles was 1.3% and the sensory score was 91.4, which reached the best under the same conditions.Then, the fresh wet rice noodles were prepared with the optimal adding amount of quality improvers selected by single factor experiments, and the noodles with the optimal adding amount of compound quality improvers selected by orthogonal experiment, with the broken rate, cooking loss rate, transmittance and gelatinization degree as the indexes, and the fresh wet rice noodles without quality improvers as control group.Under the same conditions, for the fresh and wet rice noodles with the optimal addition amount of compound quality improver, the broken rate reduced to 1.7%, cooking loss rate reduced to 1.3%, transmittance increased to 0.836, gelatinization degree increased to 92.1%, and the quality improvement effect was the best in the comparative experiment.

3D printing technology is one of the additive manufacturing technologies for rapid process and manufacture of complex geometric components. Based on the three-dimensional data model, the material is accumulated layer by layer controlled by computer, and eventually forms the solid object. Compared to the traditional manufacturing methods, 3D printing technology has many advantages, such as time saving, low cost, easy operation, no mold and strong controllability of component geometry, etc. Along with the development of this technology, several types of 3D printing technologies, such as fused deposition modeling, selective laser sintering, stereo lithography, digital light processing and solvent casting molding, have been produced according to the core of the printing technology, applicable materials and equipment composition. The principles and characteristics of the four most representative 3D printing forming processes were introduced in this paper, and the research progress of carbon nanotubes to reinforce polymer composites with different types of 3D printing forming processes applied in recent years was summarized. At the same time, it was predicted that the 3D printing molding technology will be developed towards the direction of high precision, industrialization, popularization and high integration in this field, and the research and development of 3D printing materials will also have more prospects.

NH3 is an important part of the global nitrogen cycle as the most important atmospheric alkaline gas. NH3 reacts rapidly with acidic substances and accelerates the generation of particulate matter (PM2.5), which has important effects on the atmosphere and climate change. In this study, satellite NH3 column data were used to analyze spatial and temporal distributions of NH3 in China, and because of high concentrations and rates of change, North China was selected for more detailed analysis. Qualitative analysis was conducted to understand the relations between concentrations of NH3 and those of SO2 and NO2. Last, the random forest method was used to quantify relations between concentrations of atmospheric NH3 and factors influencing those concentrations, such as meteorological factors, NH3 self-emission, and concentrations of SO2 and NO2. Satellite-retrieved NH3 column concentrations showed an increasing trend during the 11 years from 2008 to 2018, and the rate of increase in summer was faster than that in winter. In those 11 years, NH3 self-emission had the greatest influence on NH3 concentrations. Concentrations of SO2 and NO2 had some effect and were negatively correlated with NH3 concentrations. The effect of SO2 on NH3 concentration was greater than that of NO2. Atmospheric NH3 concentration was also affected by meteorological conditions (temperature, relative humidity, pressure, and wind). In summer, temperature is the most important factors of meteorological conditions and relative humidity is the most important factors in winter. Therefore, to better control atmospheric NH3 concentrations, it is particularly important to formulate practical NH3 emission reduction policies and to consider the effects of SO2 and NO2 emission reduction policies.

The quality improvement of dried noodles with high-content potato flour (33% of whole flour) was optimized by uniform design test. The main influencing factors on the quality were determined by regression analysis. The broken rate, cooking loss rate and sensory score were chosen as indicators. The results showed that the quality improver was the edible salt 0.31%, sodium carbonate 0.12%, konjac flour 0.34%, wheat gluten 2.80%, sodium polyacrylate 0.11%.With the improver the noodles cooking loss rate was 3.73%, the broken rate was 3.0% and the sensory score was 91.5. Through the research of quality improver, the quality of the sample is obviously better than the commercially available noodle, which solves the technical problems such as easy broken noodles, easy muddy soup and so on when cook dried noodles with high-content potato flour.

The effects of mono-hydrophilic colloid(xanthan gum,guar gum,sodium alginate,hydroxypropyl methylcellulose and carrageenan) on the anti-aging of tartary buckwheat parfait were studied with sensory evaluation and hardness as indexes,and three kinds of hydrophilic colloid with better anti-aging effect were screened out.Based on this,the optimal anti-aging agent of tartary buckwheat parfait was determined by response surface analysis method.The results showed that the optimal anti-aging agent formula was 0.13%of xanthan gum,0.17% of sodium alginate and 0.24% of carrageenan(calculated bytotal slurryweight).The storage time of tartary buckwheat parfait with compound hydrophilic colloids was prolonged by 2 times(14 days)of that without hydrocolloid the at-4 ℃.