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ObjectiveTo explore the importance of post-vaccination serological testing （PVST） for children exposed to hepatitis B virus （HBV）， and analyze the factors affecting the progress of PVST.MethodsThe study focused on hepatitis B surface antigen （HBsAg）-positive pregnant women and their newborns residing in Tongzhou District， Beijing， who delivered at various obstetric institutions from January 1， 2020 to March 31， 2022. The obstetric institutions and community health service centers conducted follow-up visits 1 to 2 months after the children had received three doses of the hepatitis B vaccine （HepB）.ResultsThe vaccination rate of hepatitis B immunoglobulin （HBIg） was 100.00% （800/800）， with a successful PVST follow-up rate of 85.88% （687/800） in Tongzhou District. The initial non-response rate to immunization was 0.29% （2/687）， but successful immunization was achieved after re-immunization. The mother-to-infant transmission rate of hepatitis B was 0. Children who did not undergo PVST accounted for 14.13% （113/800）， with the main reasons being delays due to the COVID-19 pandemic， parents’ reluctance to allow venous blood collection due to the young age of the children， and loss to follow-up because children moved back to their parents’ place of origin. Logistic regression analysis showed that the proportion of PVST was higher among high-risk children （OR=30.009，P=0.001）， children with family residing in Beijing （OR=2.218，P=0.002）， and children whose mothers were

When the direction-of-arrival estimation is made by a single platform, the localization accuracy decreases with increases in the distance from the radiation source, which means the localization accuracy of the azimuth of the radiation source at long distances must be improved. To address this problem, we propose a radiation-source localization algorithm based on a long synthetic aperture. This algorithm introduces the use of synthetic aperture imaging to the passive localization of radiation sources. A long virtual aperture is obtained by movement of the platform, and received data is processed in the form of synthetic aperture radar to obtain high azimuth localization accuracy. For a single-frequency radiation source, the received signal is equivalent to a linear frequency-modulation signal in the azimuth domain, and its chirp rate is inversely proportional to the distance from the radiation source. A range search and azimuth-focusing method are used to perform signal focusing in the range–azimuth domain, and the localization of the radiation source is obtained directly by two-dimensional imaging. Moreover, with respect to the characteristics of wide-beam reconnaissance, we analyzed the range–azimuth coupling relationship of the chirp rate at a low sampling frequency. On this basis, methods for direction-of-arrival estimation and two-dimensional imaging localization are proposed. Our theoretical derivation and experimental data processing results verify the validity of this algorithm.

Focusing on the problem of the space-variance of the range cell migration term for bistatic Synthetic Aperture Radar (SAR), a Scaled Inverse Fourier Transform (SIFT) based imaging algorithm for constant-offset configuration bistatic SAR data processing is proposed in this article. Range cell migration correction is realized through two times phase multiplies and one time convolution operation. Since the imaging algorithm is based on an exact precise spectrum which is deduced from the Geometry-Based Formula (GBF) algorithm, the proposed algorithm can handle the bistatic SAR data which are obtained with a large baseline to ratio. The advantages and effectiveness of the proposed imaging method have been verified by simulated and comparable experiments. Moreover, unlike the other scaling imaging algorithms which are dependent on the frequency modulated characteristics of the signal, the SIFT imaging algorithm is also suitable for phase-coded signal, which has a wider application areas.

This paper focuses on the problem of the space-variance of the range-cell migration term for bistatic Synthetic Aperture Radar (SAR) and proposes a Scaled Inverse Fourier Transform (SIFT)-based imaging algorithm for the constant-offset configuration of bistatic SAR data processing. Range-cell migration correction is realized when two times phase multiplies and a convolution operation are executed. Because the imaging algorithm is based on a precise spectrum that has been deduced from the Geometry-Based Formula (GBF) algorithm, the proposed algorithm can handle the bistatic SAR data, which were obtained with a large baseline to ratio. The advantages and effectiveness of the proposed imaging method have been verified by simulated and comparable experiments. Moreover, unlike other scaling-imaging algorithms that are dependent on the frequency modulated characteristics of the signal, the SIFT imaging algorithm is also suitable for phase-coded signals, which are used in a wider range of applications.

A new approach of 2-D MUSIC algorithm was proposed.Using the eigenvector and the eigenvalue of the co-variance matrix simultaneously,the method was composed of two one-dimension searching and avoided the costly 2-D searching.The pairings of the estimated parameters were automatically determined and the estimation precision was high.It was proved that the algorithm was valid even in the case that one of two parameters was same.Simulation results are presented to demonstrate the performance of the proposed method.

Circular synthetic aperture radar (CSAR) wins fame for its ability of multi-aspect observation and high-resolution imaging. However, special flight track and severe coupling challenge most imaging methods. To balance image quality and computational efficiency, we propose an expediting back-projection (EBP) for CSAR imaging. EBP works by dividing the full synthetic aperture into subapertures. Each subimage is formed onto the unified polar grid. Based on the relationship between azimuth time and angular wavenumber, EBP fuses subaperture spectrum together and obtains the reconstructed image followed by two-dimensional Fourier transform. Without interpolation-based fusion, EBP can decrease the loss of spectrum. Moreover, EBP retains the advantages of back-projection (BP) algorithm, such as high percision and pefect motion compensation. Experiment based on simulated CSAR data validates the effectiveness of this proposed method. [ABSTRACT FROM AUTHOR]

On the basis of the Walsh sea clutter model and measured data of over the horizon radar(OTHR), a modified OTHR sea clutter model is proposed. Ocean current, vertical motion of the ionosphere and the phase contamination which caused by nonstationarity of the ionosphere are all considered in this proposed model. Using the modified sea clutter model, the effects derived from oceanic state and nonstationarity of the ionosphere are deep analyzed based on blind zone on Doppler spectrum of ships. After comparing with the real sea clutter data, it shows that the modified OTHR sea clutter model is better than original Walsh model. The results will provide theoretical references for the optimal OTHR parameters and ionospheric channel selection. [ABSTRACT FROM AUTHOR]

Background Antiplatelet aggregation treatment has become a regular treatment of ischemic stroke. The affirmation of antiplatelet therapy is mainly derived from patients with clinical use, which can not provide the laboratory indexes for evaluation of a recognized accuracy. Studies have confirmed that the degree of platelet activation is associated with atherosclerosis and ischemic stroke, and recognized that both CD62p (α-platelet granule membrane glycoprotein) and CD63 (lysosomal membrane glycoprotein) were important indexes of platelet activation. This study aims to explore the differences of efficacy between combined use of clopidogrel and ozagrel sodium and monotherapy by aspirin in the treatment of acute ischemic stroke by investigating the expression of CD62p and CD63. Methods Flow cytometry was employed to detect CD62p and CD63 expression on circulating platelet in patients with ischemic stroke and normal control group. The positive rate of CD62p and CD63 was detected in patients with ischemic stroke who were treated with aspirin 0.15 g (single drug therapy) and clopidogrel 75 mg + ozagrel sodium 80 mg (combination therapy) before and after one and two weeks' treatment. National Institute of Health Stroke Scale (NIHSS) scores were measured in patients with ischemic stroke at the same time in three periods respectively to evaluate the improvement of neural function. Results Platelet CD62p and CD63 positive expression rate in ischemic stroke group were higher than normal control group before treatment (P = 0.001, 0.032). CD62p and CD63 positive expression rate and NIHSS score were measured at different times, and the differences were statistically significant (F = 56.693, P = 0.000; F = 21.544, P = 0.000; F = 216.271, P = 0.000, respectively). Compared with before treatment, CD62p and CD63 positive expression rate and NIHSS score decreased significantly after treatment (P = 0.000, for all), but the differences between aspirin group and combination group were not statistically significant (P > 0.05, for all). There was no interaction between the treatment groups and measuring time with CD62p and CD63 positive expression rate (F = 1.403, P = 0.250; F = 2.830, P = 0.063), while there was interaction between treatment groups and measuring time with NIHSS score (F = 4.518, P = 0.013). Conclusion Antiplatelet drug treatment of acute ischemic stroke is effective. The curative effect of combined treatment (clopidogrel and ozagrel sodium) is not superior to aspirin alone. CD62p positive expression rate in acute stage of ischemic stroke can measure the effect of antiplatelet therapy, while the determination of CD63 needs further research. [ABSTRACT FROM AUTHOR]

In order to understand the present status of nematode diversity in soil ecosystem of Abies georgei var. smithii forest, the typical forest type in subalpine zone of southeastern Tibet, an investigation was made on the nematode community in different soil layers of 0-30 cm depth from the summer, 2010 to the spring, 2011. The nematode individual density, diversity index, and trophic group index were taken to analyze the composition and structural characteristics of the soil nematode community. A total of 7915 soil nematodes belonging to 2 classes, 6 orders, 38 families, and 67 genera were collected by shallow dish method. The nematode individual density was averagely 620 nematodes · 100 g-1 dry soil, and the nematode individuals in surface soil layer (0-5 cm) accounted for 56.9% of the total, indicating the obvious surface gathering characteristics of the nematode community. Tylencholaimus, Helicotylenchus, and Plectus were the dominant genus. Plant-parasite nematode was the dominant trophic group, while fungi-feeding nematode had the largest proportion among the non plant-parasite nematodes. Soil organic matter was mainly decomposed by fungi. The ANOVA analysis indicated that there were no significant differences in the Shannon, Pielou, Margalef, and Simpson indices of soil nematode community among different seasons. The Pielou index had no significant difference among different soil layers, while the differences of Shannon, Margalef, and Simpson indices tended to be increased with increasing soil depth. It was concluded that the A. georgei var. smithii forest ecosystem in Sejila Mountain had a high maturity, with strong resistance to environment disturbances. [ABSTRACT FROM AUTHOR]

The article reports on the veterinary study of Wang Shi-feng and colleagues which determined the growth and development in the gene of sex-control in vitro after fertilization (IVF) and in vivo embryo. It states that the experiment was conducted to explore the effect of transferring sex-controlled IVF embryo. The results indicated that the pregnancy rate in IVF embryo is higher than the conventional frozen method with significant changes at different developmental stages of the fetus.

ObjectiveTo describe the neuropsychological development screening of 0‒2 years in Tongzhou from 2017 to 2021 so as to understand the status and trend of developmental delay （DD）.MethodsAnnual report data of 21 community health service centers in Tongzhou District from 2017 to 2021 were clustered， Chi square test was used to analyze the differences in positive rate and DD rate of children aged 0‒2 years with different ages and household registration， and Chi square trend test was used to analyze the linear trend of each age group and household registration. The Gesell test results in 762 children with developmental delay were analyzed， and Chi square test was used to compare the age distribution differences in gross motor， fine motor， language and personal-social behaviors.ResultsThe DD rate of children aged 0‒2 years in 2017‒2021 was 0.43％. A decreasing trend of DD rate in the 0‒ age group was observed （χ2=14.135， P

BACKGROUND The study on content and fractionation characteristics of rare earth elements (REE) in soils around different types of rare earth mining areas can provide theoretical support and scientific advice for the control of the polluted environment around the rare earth mining areas. OBJECTIVES To reveal the concentration and fractionation characteristics of REE in the soils around different types of rare earth mining areas. METHODS The content and fractionation of 15 rare earth elements in 6 soil samples from the Bayan Obo rare earth tailings area in Inner Mongolia and the Gannan rare earth mining area in Jiangxi Province were determined by the method of Community Bureau of Reference (BCR) sequential extraction and Inductively Coupled Plasma-Mass Spectrometry. RESULTS ∑REE in the soil around the mining area were 264-15955μg/g, significantly higher than the background value (186μg/g) of soils in China. LREE were enriched in the surrounding soils of the Bayan Obo mining area, and REE mainly existed in residual fraction, accounting for 64.0%-89.4% of the total content. HREE were enriched in the soils of the Gannan mining area, the main forms of REE in this area are acid-soluble fraction and reducible fraction, accounting for more than 70% of the total content. REE in the Gannan area were readily transferable and polluted the surrounding environment. CONCLUSIONS The fractionation characteristics of rare earth elements in soils are strongly correlated with pH value. With the decrease of soil pH value, the content of acid extraction fraction of rare earth elements is increasing and the content of residual fraction is decreasing.

Objective: To compare the association between body mass index (BMI) trajectories determined by different methods and the risk of overweight in early childhood in a prospective cohort study, and to identify children with higher risk of obesity during critical growth windows of early childhood., Methods: A total of 1 330 children from Peking University Birth Cohort in Tongzhou (PKUBC-T) were included in this study. The children were followed up at birth, 1, 3, 6, 9, 12, 18, and 24 months and 3 years of age to obtain their height/length and weight data, and calculate BMI Z-score. Latent class growth mixture modeling (GMM) and longitudinal data-based k -means clustering algorithm (KML) were used to determine the grouping of early childhood BMI trajectories from birth to 24 mouths. Linear regression was used to compare the association between early childhood BMI trajectories determined by different methods and BMI Z-score at 3 years of age. The predictive performance of early childhood BMI trajectories determined by different methods in predicting the risk of overweight (BMI Z-score > 1) at 3 years was compared using the average area under the curve (AUC) of 5-fold cross-validation in Logistic regression models., Results: In the study population included in this research, the three-category trajectories determined using GMM were classified as low, medium, and high, accounting for 39.7%, 54.1%, and 6.2% of the participants, respectively. The two-category trajectories determined using the KML method were classified as low and high, representing 50. 3% and 49. 7% of the participants, respectively. The three-category trajectories determined using the KML method were classified as low, medium, and high, accounting for 31.1%, 47.4%, and 21.5% of the participants, respectively. There were certain differences in the growth patterns reflected by the early childhood BMI trajectories determined using different methods. Linear regression analysis found that after adjusting for maternal ethnicity, educational level, delivery mode, parity, maternal age at delivery, gestational week at delivery, children' s gender, and breastfeeding at 1 month of age, the association between the high trajectory group in the three-category trajectories determined by the KML method (manifested by a slightly higher BMI at birth, followed by rapid growth during infancy and a stable-high BMI until 24 months) and BMI Z-scores at 3 years was the strongest. Logistic regression analysis revealed that the three-category trajectory grouping determined by the KML method had the best predictive performance for the risk of overweight at 3 years. The results were basically consistent after additional adjustment for the high bound score of the child' s diet balanced index, average daily physical activity time, and screen time., Conclusion: This study used different methods to identify early childhood BMI trajectories with varying characteristics, and found that the high trajectory group determined by the KML method was better able to identify children with a higher risk of overweight in early childhood. This provides scientific evidence for selecting appropriate methods to define early childhood BMI trajectories.

A split plot experiment was conducted in greenhouse to investigate the effects of irrigation lower limit and maize straw returning on the yield, quality, and water use efficiency (WUE) of tomato. Maize straw was applied for 1 (2018, A 1 ), 2(2017, A 2 ), and 3 (2016, A 3 ) years at different amounts (0, 1.5×10 4 , 3×10 4 , 4.5×10 4 kg·hm -2 ) and different irrigation lower limits (50%θ f , 60%θ f , 70%θ f , 80%θ f , θ f was the field water capacity). Variance analysis, entropy-weight and TOPSIS methods were used to examine the responses of yield, quality and water use efficiency (WUE) of tomato. The results showed that tomato yield was enhanced by the increases of irrigation lower limit. The maximum value of yield was observed in the 80%θ f treatments, with the maximum average yield of 93.55 t·hm -2 in A 1 , 87.23 t·hm -2 in A 2 , and 99.34 t·hm -2 in A 3 , respectively. WUE and quality of tomato decreased with increasing irrigation lower limit. In the first year of straw returning, the maximum average yield of tomato was 99.60 t·hm -2 in straw returning 1.5×10 4 kg·hm -2 . In the second and third years, 4.5×10 4 kg·hm -2 straw returning had the highest average yield of tomato, which was 92.50 and 107.75 t·hm -2 , respectively. The maximum WUE was observed with the straw returning of 1.5×10 4 kg·hm -2 in A 1 and A 2 , while in the A 3 treatment it happened in straw returning of 4.5×10 4 kg·hm -2 . The quality index of tomato showed different trends with the increases of straw returning years and amount.

To explore a new technique of planting wheat with high yield and efficiency by mulching technology in rain-fed semiarid regions in Northwest China, a two-year fixed-site trail was conducted during 2013-2015. There were five mulching modes: (1) three sowing rows by bundled straw mul-ching with alternating 30-cm-wide mulching belt and planting belt (SM 1 ), (2) four sowing rows by bundled straw mulching with alternating 40-cm-wide mulching belt and planting belt with (SM 2 ), (3) five sowing rows by bundled straw mulching with alternating 50-cm-wide mulching belt and planting belt (SM 3 ), (4) whole plastic film mulching with dibbling (PMF), (5) bare field planting without any mulching (CK). We examined the effects of different mulching modes on water consumption, water use efficiency (WUE), and yield of winter wheat in rain-fed region in Northwest China. The results showed that bundled straw mulching significantly increased soil water storage. Soil water storage with bundled straw mulching was remarkably higher than that with the whole plastic mul-ching with SM 1 ＞SM 2 ＞SM 3 . Soil water storage at 0-200 cm soil layer in flowering period was increased by 15.4%-20.8%,11.2%-14.7%and 10.1%-14.5% respectively over that in the bare field. Bundled straw mulching significantly increased water consumption during the whole growing period while reduced water consumption from sowing and flowering periods. Further, it increased water consumption from flowering to maturity periods and the ratio of water consumption during this period to the total water consumption during the whole growing periods. The results showed that mulching could increase the consumption ratio of deep water storage from the soil layer below 120 cm. Compared with CK, PMF and SM significantly increased grain yield and water use efficiency by 11.9%-19.5%, 26.9%-27.1%, respectively, and increased water use efficiency by 9.8%-13.9%, 18.4%-22.0% respectively. In all, bundled straw mulching could reduce water consumption ratio in the early growing periods, improve moisture condition, increase grain yield and water use efficiency of winter wheat. Therefore, we concluded that bundled straw mulching is an environment-friendly cultivation technology suitable for the winter wheat in semi-arid region of the Loess Plateau in Northwest China.

In order to develop a rapid detection kit for novel avian influenza virus (AIV) subtype H7N9, two sets of specific primers and probes were designed based on the nucleotide sequences of hemagglutinin antigen (HA) and neuraminidase antigen (NA) of novel H7N9 virus (2013) available in GenBank to establish the method of TaqMan probe-based multiplex real-time RT-PCR for rapid detection of AIV subtype H7N9. The primer and probe of HA were for all H7 subtype AIVs, while the primer and probe of NA were only for novel N9 subtype AIVs. The results showed that this method had high sensitivity and specificity. This method was applicable to the testing of positive standard sample with a minimum concentration of 10 copies/microL; it not only distinguished H7 subtype from H1, H3, H5, H6, and H9 subtypes, but also distinguished novel N9 subtype from traditional N9 subtype. A total of 2700 samples from Zhuhai, China were tested by this method, and the results were as expected. For the advantages of sensitivity and specificity, the method holds promise for wide application.

In order to study the proliferation inhibition effect of H5N1 subtype avian influenza virus (AIV) with small interfere RNA (siRNA), a total of 4 siRNAs were designed in accordance with the NP and PA genes of H5N1 subtype AIV, the siRNAs were then transfected to chicken embryo fibroblast(CEF), CEF was infected with H5N1 subtype AIV after 6 hrs. Virus titer of cell supernatant was tested at 16-56hrs post infection, and pathological changes of the cells was observed; mRNA levels of NP, PA, HA and p13-actin gene were tested at 36hrs post infection. The results showed that these 4 siRNAs could inhibit the prolif-eration of H5N1 subtype AIV in CEF in varying degrees, and one siRNA targeting PA was best per-formed. The experimental results also showed that the inhibition effect was decreased with the time prolonged. This research provides a basis for further studying RNAi on AIV prevention and control.

In order to understand the present status of nematode diversity in soil ecosystem of Abies georgei var. smithii forest, the typical forest type in subalpine zone of southeastern Tibet, an investigation was made on the nematode community in different soil layers of 0-30 cm depth from the summer, 2010 to the spring, 2011. The nematode individual density, diversity index, and trophic group index were taken to analyze the composition and structural characteristics of the soil nematode community. A total of 7915 soil nematodes belonging to 2 classes, 6 orders, 38 families, and 67 genera were collected by shallow dish method. The nematode individual density was averagely 620 nematodes x 100 g(-1) dry soil, and the nematode individuals in surface soil layer (0-5 cm) accounted for 56.9% of the total, indicating the obvious surface gathering characteristics of the nematode community. Tylencholaimus, Helicotylenchus, and Plectus were the dominant genus. Plant-parasite nematode was the dominant trophic group, while fungi-feeding nematode had the largest proportion among the non plant-parasite nematodes. Soil organic matter was mainly decomposed by fungi. The ANOVA analysis indicated that there were no significant differences in the Shannon, Pielou, Margalef, and Simpson indices of soil nematode community among different seasons. The Pielou index had no significant difference among different soil layers, while the differences of Shannon, Margalef, and Simpson indices tended to be increased with increasing soil depth. It was concluded that the A. georgei var. smithii forest ecosystem in Sejila Mountain had a high maturity, with strong resistance to environment disturbances.

An on-line method for measurement of the 13C/12C ratio of methane by a gas chromatography/high-temperature conversion/ isotope ratio mass spectrometry (GC/C/MS) technique was developed. This method is less laborious, more rapid (45 min), of high precision (+/- 0.4 x 10(-3)) and by using a small amount of sample (about 200 mL of atmosphere). Its application to isotopic characterization, and hence methane source identification, was demonstrated by examination of atmosphere sample collected in Yakela condensed gas field, China. The average 13C/12C ratio of atmospheric methane in Yakela field was -45.0 x 10(-3) heavier by 1.2 x 10(-3) -2.0 x 10(-3) than the global average. This is caused by seepage and diffusing of methane from Yakela condensed gas reservoir. The concentrations of atmospheric methane in daytimes are found to be lower than those in nighttimes, and the corresponding 13C/12C ratios in daytimes are lighter compared to those in nighttimes, a phenomena probably caused by the fact that a small part of methane from Yakela condensate reservoir is consumed in soil's surface under sunlight.

Objective: To investigate the effect of ceramide monohexoside (CMH) on resistance to cisplatin and apoptosis in ovarian cell line COC1/DDP, and to provide new ideals and clues to seek new effective methods for studying the mechanism and reversing the resistance in ovarian cell line as well., Methods: COC1 cells and COC1/DDP cells (before and after the treatment of mifepristone) were collected and neutral glycosphingolipids (N-GSLs) of the cells was isolated and purified, changes of CMH content were analyzed by high performance thin layer chromatography (HPTLC). The COC1/DDP cells were divided into three groups, one treated by cisplatin, one treated by mifepristone, the other treated by cisplatin and mifepristone. The survival rate of cells in three groups were evaluated by the methyl thiazolyl tetrazolium (MTT) assay, DNA ladders were presented by DNA gel electrophoresis, the forms of cells were observed by transmission electron microscope (TEM)., Results: The levels of CMH were (37.1 +/- 3.3)% in COC1/DDP, higher than that in COC1 (14.1 +/- 1.4)% (P < 0.001). After treating by 1.25, 5 micro mol/L mifepristone, the CMH were (26.6 +/- 2.6)% (P < 0.05) and (17.5 +/- 0.7)% (P < 0.001), respectively. Mifepristone had no effect on the viability of COC1/DDP cell below a concentration of 5 micro mol/L. But when mifepristone of 1.25 or 5 micro mol/L combined with cisplatin at a concentration of 0.1, 0.25, 0.5, 1.25, 2.5 micro g/ml, the inhibition rate of COC1/DDP cell is higher than that of COC1/DDP cells only treated by cisplatin at the concentration of 0.1 to 2.5 micro g/ml (P < 0.001). The combined treatment elicited DNA fragmentation, however, neither cisplatin of 1.25 micro g/ml nor mifepristone of 5 micro mol/L alone could potentiate DNA fragmentation. After the combined treatment, the COC1/DDP cells produced apoptosis body., Conclusions: CMH is related with resistance to cisplantin in ovarian cell line COC1/DDP. When CMH of COC1/DDP cells was inhibited by mifepristone, the cells were sensitive to cisplatin and apoptosis was elicited.

Objective: To explore an ideal technique for remodeling the breast after resection of large breast fibroadenoma., Methods: Based on the principle of breast reduction, an operation plan was designed. The new locations of the nipple, and the areola and the area of the breast skin to be resected were marked. The preoperative-marked skin, epidermis, and the whole breast tumor were resected routinely. Then breast remodeling followed according to augmentation mammoplasty. Seven patients underwent this operation., Results: The operative results were satisfactory in terms of multiple parameters during the follow-up period., Conclusions: This operation can effectively resect the breast tumor and remodel the breast simultaneously.