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Arginine vasopressin (AVP) is a key contributor to heart failure (HF), but the underlying mechanisms remain unclear. In the present study, a mouse model of HF and human cardiomyocyte (HCM) cells treated with dDAVP are generated in vivo and in vitro, respectively. Hematoxylin and eosin (HE) staining is used to evaluate the morphological changes in the myocardial tissues. A colorimetric method is used to measure the iron concentration, Fe2+ concentration and malondialdehyde (MDA) level. Western blot analysis is used to examine the protein levels of the V1a receptor (V1aR), calcineurin (CaN), nuclear factor of activated T cells isoform C3 (NFATC3), glutathione peroxidase 4 (GPX4) and acyl-CoA synthase long chain family member 4 (ACSL4). Immunoprecipitation (IP) and luciferase reporter assays are performed to determine the interaction between NFATC3 and ACSL4. Both in vivo and in vitro experiments reveal that the V1aR-CaN-NFATC3 signaling pathway and ferroptosis are upregulated in HFs, which are verified by the elevated protein levels of V1aR, CaN, NFATC3 and ACSL4; reduced GPX4 protein level; and enhanced Fe2+ and MDA levels. We further find that inhibiting NFATC3 by suppressing the V1aR/CaN/NFATC3 pathway via V1aR/CaN inhibitors or sh-NFATC3 not only alleviates HF but also inhibits AVP-induced ferroptosis. Mechanistically, sh-NFATC3 significantly reverses the increase in AVP-induced ACSL4 protein level, Fe2+ concentration, and MDA level by directly interacting with ACSL4. Our results demonstrate that AVP enhances ACSL4 expression by activating the V1aR/CaN/NFATC3 pathway to induce ferroptosis, thus contributing to HF. This study may lead to the proposal of a novel therapeutic strategy for HF.

ObjectiveTo explore the relationship between macronutrient intake and sleep quality， the current sleep quality of pregnant women from ten cities in China was investigated.MethodsMultistage stratified sampling was used to investigate the nutrient intake and sleep quality of 863 pregnant women in ten Chinese cities. Twenty-four dietary intake， sleep quality， perinatal depression， and other information was obtained using physical measurements and a questionnaire. Logistic and multiple linear regression models were used to explore the relationship between macronutrient intake and sleep quality.ResultsThe prevalence of poor sleep quality among pregnant women was 46.12%； pregnant women who were in the third trimester， who had depression， were currently unemployed， passively smoked during pregnancy， and had a history of previous alcohol consumption， demonstrated a higher levels of poor sleep quality （P

Fermented dairy products undergo structural and textural changes during fermentation， resulting in the production of unique nutrients. Therefore， they have special flavors and nutritional characteristics， offering health benefits for middle-aged and older adults， based on relevant evidence from global cohort studies. This article reviews evidence from global long-term follow-up cohort studies investigating the associations between fermented dairy products intake and overweight/obesity， cardiovascular and cerebrovascular diseases， prediabetes and diabetes， cognition， and tumorigenesis. Additionally， this review explores the potential mechanisms for these associations.

Background: Observational studies suggest a potential association between atmospheric particulate matter 2.5 (PM2.5) and osteoporosis, but a causal association is unclear due to the presence of confounding factors.Methods: We utilized bone mineral density indices at four specific sites to represent osteoporosis: femoral neck (FN-BMD), lumbar spine (LS-BMD), forearm (FA-BMD), and heel (HE-BMD). The PM2.5 data was obtained from the UK Biobank database, while the datasets for FN-BMD, LS-BMD, and FA-BMD were obtained from the GEFOS database, and the dataset for HE-BMD was obtained from the EBI database. A two-sample Mendelian randomization analysis was conducted using mainly the inverse variance weighted method, horizontal pleiotropy and heterogeneity were also assessed.Results: The results indicated that PM2.5 was not correlated with a decrease in FN-BMD (β: −0.305, 95%CI: −0.762, 0.153), LS-BMD (β: 0.134, 95%CI: −0.396, 0.666), FA-BMD (β: -0.056, 95%CI: −1.172,1.060), and HE-BMD (β: −0.084, 95%CI: −0.261,0.093). Additionally, acceptable levels of horizontal pleiotropy and heterogeneity were observed.Conclusion: In contrast to most observational studies, our research did not discover a potential causal relationship between PM2.5 and the development of osteoporosis.

TBM hob wear is an important factor that affects the TBM tunneling efficiency and construction cost.Different blade types differ in rock breaking efficiency and wear.By analyzing the rock-breaking mechanism of the arc blade wedged hob, this study established the calculation model of hob normal cutting, and analyzed the influence of hob edge angle on normal cutting force.This study then designed three kinds of hobs with different cutter spacing and three types of hobs with different blade for rock breaking tests in laboratory.Results show that the reasonable cutter spacing is 15mm, sharp blade is prone to be worn, the tooth-like blade, which has higher rock breaking efficiency and wear resistance, is better than arc blade.Combined with the actual situation of the project site, a new hob with wedge-shaped blade is developed, which are applied to inclined shaft TBM tunneling at engineering site.Results show that the wear rate of the new wedge-shaped hob is 20 % less than that of the conventional ones, and the service life of former is longer than that of latter.Under the same geological conditions, new wedge-shaped hob can reduce the number of hobs consumption and improve efficiency of tunnelling.The development and application of the new type successfully solved the problems of hob wear and frequent replacement of hobs in the TBM inclined shaft excavation.It can provide technical support for TBM long distance inclined shaft driving, which not only shortened the construction period, but also saved the construction cost.

Background Acute kidney injury (AKI) is not a rare complication during anti-tuberculosis treatment in some patients with pulmonary tuberculosis (PTB). We aimed to develop a risk prediction model for early recognition of patients with PTB at high risk for AKI during anti-TB treatment.Methods This retrospective cohort study assessed the clinical baseline, and laboratory test data of 315 inpatients with active PTB who were screened for predictive factors from January 2019 to June 2020. The elements were analyzed by logistic regression analysis. A nomogram was established by the results of the logistic regression analysis. The prediction model discrimination and calibration were evaluated by the concordance index (C-index), ROC curve, and Hosmer-Lemeshow analysis.Results A total of 315 patients with PTB were enrolled (67 patients with AKI and 248 patients without AKI). Seven factors, including microalbuminuria, hematuria, cystatin-C (CYS-C), albumin (ALB), creatinine-based estimated glomerular filtration rates (eGFRs), body mass index (BMI), and CA-125 were acquired to develop the predictive model. According to the logistic regression, microalbuminuria (OR = 3.038, 95%CI 1.168–7.904), hematuria (OR = 3.656, 95%CI 1.325–10.083), CYS-C (OR = 4.416, 95%CI 2.296–8.491), and CA-125 (OR = 3.93, 95%CI 1.436–10.756) were risk parameter, while ALB (OR = 0.741, 95%CI 0.650–0.844) was protective parameter. The nomogram demonstrated good prediction in estimating AKI (C-index= 0.967, AUC = 0.967, 95%CI (0.941–0.984), sensitivity = 91.04%, specificity = 93.95%, Hosmer-Lemeshow analysis SD = 0.00054, and quantile of absolute error = 0.049).Conclusions Microalbuminuria, hematuria, ALB reduction, elevated CYS-C, and CA-125 are predictive factors for the development of AKI in patients with PTB during anti-TB treatments. The predictive nomogram based on five predictive factors is achieved good risk prediction for AKI during anti-TB treatments.

Stress fractures are rare, occurring in 1.5/100,000 high school athletes. High impact, repetitive loading participation in woman's sports, and being a white athlete have been identified as risk factors for stress fractures. Mostly treated conservatively, they are more common in the tibia (33%). Stress fractures requiring surgery, which are extremely rare, have been reported in the scaphoid, fifth metatarsal, and neck of femur. Herein, a 16-year-old adolescent patient with obesity presented with atypical knee pain after prolonged exercise. Advanced imaging revealed a stress fracture of the left tibia with a Salter–Harris type V fracture and varus deformity of the knee. We initially managed the fatigue fracture conservatively, followed by surgical correction of the varus deformity in the knee joint. The patient made a satisfactory recovery with equal limb length and no evidence of claudication. This is the first case of a proximal tibial metaphyseal stress fracture requiring surgery. The clinical manifestations of proximal tibial metaphyseal stress fractures and potential treatment strategies and the use of magnetic resonance for tibial stress fractures have been discussed. Understanding the location of unusual stress fractures can improve early diagnostic efficiency and reduce complication rates, healthcare costs, and recovery time.

Purpose To analyze the clinical effect and imaging data of cementless bipolar hemiarthroplasty employing a long femoral stem (peerless-160) and 2 reconstructed femoral titanium wires to repair intertrochanteric fractures among the octogenarians. Methods Between June 2014 and August 2016, 58 octogenarians with femoral intertrochanteric fractures underwent the long femoral stem (peerless-160) cementless bipolar hemiarthroplasty by the same surgeon. We assessed clinical and radiological outcomes such as operative time, bleeding volume, blood transfusion volume, length of hospital stay, full weight-bearing walking time, walking ability calculated by Koval classification and Harris Hip Score (HHS), including fracture healing and greater trochanter fragments subsidence. Result The surgery was successfully performed in all patients. The average operation time was 72.8 ± 13.2 min, the average blood loss during surgery was 225.0 ± 91.4 mL, 200 mL of blood was transfused, the mean duration of hospitalization was 11.9 ± 4.0 days, the mean time of full weight bearing was 12.5 ± 3.8 days. Patients were followed up for 24-68 months, averagely 49.4 ± 10.3 months. During follow-up, 4 (6.9%) patients died, and 1 (1.7%) was completely lost to ask about the recent situation. The average Harris Hip Score at the last follow-up was 87.8 ± 6.1, most of the patients recovered walking ability, under radiological examination, the prosthesis showed no signs of loosening. All trochanteric fractures gradually healed, the clinical and radiographic signs of healing occurred at average of 4.0 ± 1.1 months postoperatively. Conclusion For osteoporotic unstable intertrochanteric fractures in octogenarians, this study confirmed that the Cementless Bipolar Hemiarthroplasty Using a Long Femoral stem (peerless-160) with double cross binding technique is a satisfactory and safe choice for the octogenarians.

Abstract Objectives To explore the association between CT-derived pectoralis muscle index (PMI) and COVID-19 induced lung injury. Methods We enrolled 116 elderly COVID-19 patients linked to the COVID-19 outbreak in Nanjing Lukou international airport. We extracted three sessions of their CT data, including one upon admission (T1), one during the first 2 weeks when lung injury peaked (T2) and one on day 14 ± 2 (T3). Lung injury was assessed by CT severity score (CTSS) and pulmonary opacity score (POS). Pneumonia evolution was evaluated by changes of CT scores at T2 from T1(Δ). Results The maximum CT scores in low PMI patients were higher than those of normal PMI patients, including CTSS1 (7, IQR 6–10 vs. 5, IQR 3–6, p 4. The presence of low PMI (OR = 5.98, p 4. Meanwhile, presence of low PMI (OR = 2.82, p = 0.042) and incrementally increasing D-dimer (OR = 0.088, p = 0.024) were predictors of lung injury aggravation with ΔPOS = 2. Conclusions PMI can be easily assessed on chest CT images and can potentially be used as one of the markers to predict the severity of lung injury in elderly COVID-19 patients.

Aim: To explore the risk factors of prolonged viral shedding time (VST) in critical/non-critical COVID-19 patients during hospitalization. Methods: In this retrospective study, we enrolled 363 patients with SARS-CoV-2 infection admitted in a designated hospital during the COVID-19 outbreak in Nanjing Lukou International Airport. Patients were divided into critical (n = 54) and non-critical (n = 309) groups. We analyzed the relationship between the VST and demographics, clinical characteristics, medications, and vaccination histories, respectively. Results: The median duration of VST was 24 d (IQR, 20–29) of all patients. The VST of critical cases was longer than non-critical cases (27 d, IQR, 22.0–30.0 vs. 23 d, IQR 20–28, P

The article analyzes the everyday communication of Chinese students in the Far East of the Russian Federation. The empirical data are based on two studies conducted by the staff of the Institute of the East, Higher Education Research Institute of Harbin Institute of Technology and the Interdepartmental sociological laboratory of The Institute of Finances and Economics of North-Eastern Federal University in 2017 and 2019. The methodological approach of the research, based on the theory of social space, allows us to conventionally distinguish the educational field and types of neighborhood subfields. As a structure of such fields of everyday communication in a foreign ethnic environment, the following are identified: the duration of students’ stay depending on educational programs, the level of Russian language proficiency, place of residence, roommates in a dormitory, the level of material well-being of the students’ family. Of course, it is by no means denied that the main tone in the life of students is set by the cognitive environment of the learning process. The data obtained make it possible to conditionally distinguish three types of neighborhoodhousehold subfields in the everyday extra-curricular life of students: the first can be attributed to students living with their compatriots, some of whom, having quickly adapted to local conditions, may experience difficulties in mastering the Russian language, respectively, and in general in study. The second type may include respondents who have expressed a desire to live with representatives of the local student community for closer contact with them in order to better master the Russian language. Of course, they experience difficulties at the initial stage of adaptation, which can then be compensated for by the achievement of the set goal, good command of the Russian language, the establishment of friendly relations, not only with roommates, etc. The third type can be formed by those who initially have mastered the Russian language at a sufficient level, who can communicate and study in Russia without any problems. They can live both with their fellow countrymen and with Russian students.

ObjectivesTo summarize the clinical characteristics of patients infected by SARS-CoV-2 omicron variant and explore the risk factors affecting the progression in a Fangcang hospital, Shanghai, China.MethodsA total of 25,207 patients were retrospectively enrolled. We described the clinical characteristics and performed univariate and multivariate logistic regression analysis to identify the risk factors for non-severe to severe COVID-19 or death.ResultsAccording to the outcomes, there were 39 severe patients (including 1 death) and 25,168 non-severe patients enrolled in this study. Among the 25,207 cases, the median age was 45 years (IQR 33-54), and 65% patients were male. Cough (44.5%) and expectoration (38.4%) were the most two common symptoms. Hypertension (10.4%) and diabetes (3.5%) were most two common comorbidities. Most patients (81.1%) were fully vaccinated. The unvaccinated and partially vaccinated patients were 15.1% and 3.9%, respectively. The length of viral shedding time was six days (IQR 4-9) in non-severe patients. Multivariate logistic regression analysis suggested that age (OR=1.062, 95%CI 1.034-1.090, p

The decay and holding time of nitrogen concentration was characterized in a controlled-atmosphere warehouse with half life of pressure of 165 s. The relationship of nitrogen concentration, nitrogen holding timeand grain temperature was further studied. The results showed that, the nitrogen concentration gradually decreases with the time, when the nitrogen concentration in the controlled-atmosphere warehouse reached to the target concentration of 98.0%. The concentration of nitrogen was related to nitrogen leakage and sorption.An increase of the nitrogen concentration required that the amount of supplemental nitrogen is greater than the amount of leakage. When there is no nitrogen supplement in the controlled-atmosphere warehouse, the monthly decrease of nitrogen concentration is 1.6%; when the monthly nitrogen supplement is greater than 12.4% of the grain warehouse volume, the nitrogen concentration will increase by 0.1% ～ 0.9%; the monthly nitrogen supplement is greater than 27.0% of the grain warehouse volume, the nitrogen concentration will greater than 1.0%. In addition, the amount of nitrogen supplementation has no direct effect on the temperature of the grain.

As one of the core hot components of aeroengines, the safe service of turbine blades is crucial to the operation of aeroengines.When the aeroengines encounter some emergency conditions, the turbine blades may suffer overheating, the temperature of which is much higher than the highest normal operating temperature. Overheating can lead to serious microstructural degradation and even premature failure of turbine blades. In this paper,the methods of overheat inspection and failure analysis were introduced, as well asthe effects of overheating on the microstructural degradation and mechanical propertiesof aeroenginesturbine blades. In addition, the damage assessment, life prediction and microstructure rejuvenation of superalloys after overheating were prospected in this paper, which provide a guidance and theoretical basis for the degradation evaluation and failure analysis of turbine blades as well as the development of new superalloys.

Meningioma and auditory neuroma are two types of brain tumors frequently found in the cerebellopontine angle. Misdiagnosis of the two is common due to their similarity in clinical manifestations and imaging manifestations. In this work, the deep learning algorithm was developed to classify the meningioma and auditory neuroma from the magnetic resonance images, assisting the timely and accurate diagnosis to the two brain tumors. T1-weighted spin-echo (T1W-SE) images were collected from 307 patients with brain tumors. Contrast limited adaptive histogram equalization (CLAHE) pre-processing was used to improve the quality of the dataset. The image features were learnt in the deep learning framework of 3-dimensional convolutional neural network (3D CNN). By optimizing the image enhancement parameters and the network structure parameters, the accuracy of the meningioma/acoustic neuroma classification model reached 0.918 0, and the area under curve (AUC) was found to be 0.913 4.

Soil fungi play an important role in the process of planting tea tree. However, effects of acidification on the diversity and function of the fungi community in tea rhizosphere soil have been rarely reported. In this study, tea rhizosphere soils with pH of 3.3, 4.7, 5.3 and 6.4 were investigated for diversity and function of fungal communities through T-RFLP technology. The results showed that the abundance and diversity of fungi increased significantly with the decrease of pH value of rhizosphere soil. The results of significance analysis showed that 38 T-RFs fragments were significantly correlated with pH value, among which 32 were negatively correlated with pH value and 6 were positively correlated with pH value. After database comparison, 23 fungi were identified and classified according to their nutritional patterns, which can be divided into four types, including pathotroph, symbiotroph, saprotroph and unknown, accounting for 36.85%, 7.89%, 15.79% and 39.47%, respectively. At pH value of 3.3, the fungus abundance reached the maximum value. In conclusion, acidification leads to changes in the structure and diversity of the fungi community in tea rhizosphere soil, specifically, a significant increase in the number and species of fungi, of which the pathotroph type is the largest. This study provides an important theoretical basis for controlling fungal diseases of tea tree in acidified tea plantations

Objective To investigate the expression and correlation of pigment epithelium derived factor (PEDF) and androgen receptor (AR) in bladder cancer tissues. Methods The expression of PEDF and AR in 30 cases of bladder cancer tissues were detected by immunohistochemical staining. The relation between PEDF expression and AR was analyzed by Pearson correlation. We detected the expression levels of PEDF and AR in bladder cancer TCCSUP cell line and the expression of PEDF after lentivirus-mediated AR interference by Real-time PCR and Western blot. Results PEDF expression was negatively correlated with AR expression(P=0.003). Androgen could significantly upregulate AR expression and inhibit PEDF expression. At the same time, interfering AR expression could upregulate the expression of PEDF. Conclusion The expression of PEDF may be inhibited by AR expression in bladder cancer tissues.

Two bicrystal specimens containing high angle grain boundary (about 20 degrees) were prepared by seed crystal method. The effect of Hf on the as-cast, heat-treated grain boundary microstructure, composition and stress rupture properties under 1100℃/100MPa was investigated in Ni-based single crystal superalloy contained Re with different contents of Hf (mass fraction:0%, 0.4%). The results show that Hf addition results in the increase of the volume fraction of (γ+γ') eutectic and MC along the grain boundary. The volume fraction of cellular recrystallization microstructure is significantly decreased after heat treatment with Hf addition. The transverse stress rupture life is observed to increase significantly under 1100℃/100MPa in the Hf-containing alloy. The stress rupture properties are closely related to the type, morphology, content and composition of the precipitation phase along grain boundary, but the obvious segregation of Hf is not observed. This study can be helpful for the understanding of Hf's role of strengthening mechanism in grain boundary in advanced Ni-based single crystal superalloy.

In this letter, we consider the single-carrier frequency domain equalization (SC-FDE) system, and propose a low-complexity joint symbol detection and channel estimation algorithm based on the recently proposed vector approximate message passing (VAMP). Specifically, we leverage VAMP twice to estimate symbols and channels, respectively, in a turbo-like way. Moreover, this algorithm organically combines the gaussian mixture model (GMM), which can accurately simulate the sparse aggregation characteristics of the channel and effectively suppress inter symbol interference (ISI). The simulation results show that compared with the traditional linear minimum mean square error (LMMSE) estimation receiving algorithm and the existing generalized approximate message passing algorithm (GAMP), the designed receiving algorithm has significant advantages in channel estimation normalized mean square error (NMSE) and bit error ratio (BER) performance, where sharing the same order of complexity.

This paper presents the development of artificial intelligence and the necessity of teaching reforms in the teaching of translation technology. By analyzing the teaching process in the first national translation technology teaching competition in 2021, it explores the classroom practice model of translation technology in China from four main dimensions -teaching philosophy, teaching content, teaching methods, and teaching evaluation. It then sheds light on some difficult points in the teaching technology model with the purpose of providing new insights for the teaching practice of translation technology.

The influences of withdrawal rate and mold heater zone temperature during high rate solidification (HRS) on the microstructures were investigated. As the results, the primary dendritic spacing, the size of γ′ phase particles and carbides are decreased with the increase of the withdrawal rate or mold heater zone temperature. As the withdrawing goes on, the primary dendritic spacing and the size of γ′ phase particles are increased, and the heat emission efficiency of HRS process is decreased. The results show that fine dendrite and γ′ phase can be achieved with the withdrawal of 8 mm/min and mold heater zone temperature of 1520 ℃/1530 ℃, which is benefit to improve the properties of DZ466 alloy.

The traditional estimation methods of space targets pose are based on artificial features to match the transformation relationship between the image and the object model. With the explosion of deep learning technology, the approach based on deep neural networks (DNN) has significantly improved the performance of pose estimation. However, the current methods still have problems such as complex calculation, low accuracy, and poor real-time performance. Therefore, a new pose estimation algorithm is proposed in this paper. Firstly, the mask image of the target is obtained by the instance segmentation algorithm, and its point cloud image is obtained based on a depth map combined with camera parameters. Finally, the correlation among points is established to realize the prediction of pose based on multi-modal feature fusion. Experimental results in the YCB-Video dataset show that the proposed algorithm can recognize complex images at a speed of about 24 images per second with an accuracy of more than 80%. In conclusion, the proposed algorithm can realize fast pose estimation for complex stacked objects and has strong stability for different objects.

Object detection and segmentation can improve the accuracy of image recognition, but traditional methods can only extract the shallow information of the target, so the performance of algorithms is subject to many limitations. With the development of neural network technology, semantic segmentation algorithms based on deep learning can obtain the category information of each pixel. However, the algorithm cannot effectively distinguish each object of the same category, so YOLOMask, an instance segmentation algorithm based on complementary fusion network, is proposed in this paper. Experimental results on public data sets COCO2017 show that the proposed fusion network can accurately obtain the category and location information of each instance and has good real-time performance.

A robot can identify the position of a target and complete a grasping based on the hand–eye calibration algorithm, through which the relationship between the robot coordinate system and the camera coordinate system can be established. The accuracy of the hand–eye calibration algorithm affects the real-time performance of the visual servo system and the robot manipulation. The traditional calibration technique is based on a perfect mathematical model AX = XB, in which the X represents the relationship of (A) the camera coordinate system and (B) the robot coordinate system. The traditional solution to the transformation matrix has a certain extent of limitation and instability. To solve this problem, an optimized neural-network-based hand–eye calibration method was developed to establish a non-linear relationship between robotic coordinates and pixel coordinates that can compensate for the nonlinear distortion of the camera lens. The learning process of the hand–eye calibration model can be interpreted as B=fA, which is the coordinate transformation relationship trained by the neural network. An accurate hand–eye calibration model can finally be obtained by continuously optimizing the network structure and parameters via training. Finally, the accuracy and stability of the method were verified by experiments on a robot grasping system.

Dexterous manipulation of the robot is an important part of realizing intelligence, but manipulators can only perform simple tasks such as sorting and packing in a structured environment. In view of the existing problem, this paper presents a state-of-the-art survey on an intelligent robot with the capability of autonomous deciding and learning. The paper first reviews the main achievements and research of the robot, which were mainly based on the breakthrough of automatic control and hardware in mechanics. With the evolution of artificial intelligence, many pieces of research have made further progresses in adaptive and robust control. The survey reveals that the latest research in deep learning and reinforcement learning has paved the way for highly complex tasks to be performed by robots. Furthermore, deep reinforcement learning, imitation learning, and transfer learning in robot control are discussed in detail. Finally, major achievements based on these methods are summarized and analyzed thoroughly, and future research challenges are proposed.

This paper aimed to evaluate the changes in the thermal stability of goat milk, cow milk and homogenized milk under different pH conditions. The results showed that goat milk was of type B milk, and the thermal stability were positively correlated with the pH value. But cow milk was of type A milk, the most stable pH of fresh milk was 6.9, while it was 6.7 for homogenized cow milk. Compared with cow milk, the acidification of goat milk was stronger due to heat. Therefore, in the process of milk production, the germicidal heating conditions of two different milk sources should be determined according to their thermal stability.

The present study aimed to determinate the content of immunoglobulin G (IgG) in goat colostrum and the effected factors were discussed by single radial immunodiffusion. The results showed that the highest level of IgG was detected in the first day after partum, and decreased quickly over the length of the lactation period. No significant effect on IgG was seen with different ways of thawing and the different freezing time. IgG was almost completely lost at 85°C for 2 min. The maximum value of IgG was observed at pH 6.5, and it reduced significantly when the pressure was higher than 500MPa, and decreased with the increase of the concentrations of citric acid and Ca2+.

Aiming at the problem that the frequency offset in the non-cooperative communication system causes the received signal spectrum to shift, which exceeds the passband of the matched filter and affects the subsequent demodulation, a parameter estimation and signal detection algorithm based on adaptive capture is proposed by this paper, which is more convenient for hardware implementation and consumes less resources. The algorithm is divided into three parts. Firstly, use the correlation value between the signal and the preamble sequence as the basis for frequency capture. Secondly, the frequency is accurately estimated based on the interpolation algorithm. Finally, the phase-locked loop structure is used to track the frequency according to the characteristics of the frequency gradually changing and the signal frequency offset is eliminated in the Digital Down Converter stage. It provides necessary conditions for accurate signal detection and phase estimation. The simulation results show that the algorithm has high estimation accuracy, wide esti-mation range and low complexity. It can also achieve better estimation accuracy and detection performance under low signal-to-noise ratio.