Provinces In Southern China Research Articles

Evaluating resistance drilling and NIR spectroscopy for quantifying wood quality of young eucalypts grown in Guangxi province in southern China

Cost-effective, non-destructive means of estimating wood properties of eucalypts grown in Guangxi, China, were evaluated using near infrared (NIR) spectroscopy and resistance drilling. For this evaluation, wood samples for NIR analysis and resistance drill measurements were collected from 581 trees, representing eight plantation Eucalyptus taxa across five sites. The near infra-red (NIR) spectra collected from the 581 wood samples were analysed using existing calibrations for kraft pulp yield, cellulose content, hot water extractives and Klason lignin. These spectra and calibrations were effective in predicting over 60% of the variance in total carbohydrates and over 80% of the extractives and lignin values from independent laboratory analysis of a subset of 100 samples. Resistance drilling combined with software developed for processing the drill data proved to be a quick, low cost and effective means of quantifying wood density (as amplitude of the drill torque), stem diameter and bark thickness.

Analysis of the Effect of Meteorological Elements on New Energy Power Prediction Based on Machine Learning

Background: With the gradual construction of new power systems, new energy sources, such as wind and photovoltaic power, will gradually dominate positions in the power supply structure, directly leading the new power system to rely heavily on accurate meteorological forecasts. High-precision and high-resolution meteorological forecasts are important technical methods to improve the safe, stable, and economic operation of the new power system. Objective: Since the analysis of meteorological elements is the basis of meteorological forecasting, in this paper, the effect of different meteorological elements including temperature, relative humidity, air pressure, wind speed, wind direction, and radiation on the performance of power forecasting, was analyzed by using 7 machine learning algorithms in 5 provinces in southern China. Methods: About 5 provinces in southern China were selected as the research objects, and 7 typical machine learning algorithms were applied and compared, including support vector machine (SVM), decision tree (DT), random forest (RFR), K-nearest neighbor (KNN), Linear Regression (LR), Ridge Regression (RR), and Lasso Regression (Lasso R). At the same time, the influence of different meteorological elements, such as temperature, relative humidity, air pressure, wind speed, wind direction, and radiation amount, on the prediction performance of wind power and photovoltaic power was considered. Then, the performance of different regression models was further investigated and analyzed. Results: Based on the data of 10 new energy stations in 5 regions, the research on the prediction performance of 7 machine learning methods shows that the performance of models in different regions varies greatly. Among the 10 selected new energy stations, the RFR model and KNR model have superior overall performance. Conclusion: This study shows how variable importance and prediction accuracy depend on regression methods and climatic variables, providing effective methods to assess the interdependence of meteorological variables and the importance of meteorological variables in predicting output power.

A coupled PSR-based framework for holistic modeling and flood resilience assessment: A case study of the 2022 flood events in five southern provinces of China

In the context of global climate change, the increasing frequency of extreme weather events has led to increasingly severe disaster situations. Traditional disaster management approaches are inadequate for addressing these challenges; thus, the concept of resilience has gradually been integrated into disaster management strategies. This study addresses this gap by developing a semi-quantitative evaluation framework for flood resilience on a large, regional scale. This framework combines the Pressure-State-Response (PSR) model with a dynamic representation of flood resilience processes, incorporating pre-disaster resistance, during-disaster absorption, and post-disaster recovery. A comprehensive regional flood resilience index system (RFRI) is constructed to provide a holistic assessment of flood resilience throughout the disaster cycle. This study quantified flood resilience and utilized Geographic Information System spatial analysis to evaluate the spatial patterns of flood resilience at the municipal level. The evaluation framework was applied to a real flood disaster that affected five southern provinces of China in 2022. The results indicate that: (1) The overall flood resilience levels in the five southern provinces were relatively low, with only 6% of the units having a Flood Resilience Index (FRI) exceeding 0.6; and (2) in terms of pre-disaster resistance, 74% of municipalities in the five southern provinces of China exhibited a moderate or higher level of resilience. However, the overall performance of these provinces is relatively poor in terms of absorption during disasters and post-disaster recovery; (3) The development of flood resilience systems in the five provinces was severely imbalanced, with only two municipal-level cities having an FRI above 0.8, both of which are located in Guangdong Province. The evaluation framework established in this study enables rapid and accurate quantitative assessment of flood resilience at the municipal level. It aids in identifying deficiencies in the flood resilience systems of various regions, thereby strengthening efforts to build flood resilience.

Multi-Time-Scale Energy Storage Optimization Configuration for Power Balance in Distribution Systems

As the adoption of renewable energy sources grows, ensuring a stable power balance across various time frames has become a central challenge for modern power systems. In line with the “dual carbon” objectives and the seamless integration of renewable energy sources, harnessing the advantages of various energy storage resources and coordinating the operation of long-term and short-term storage have become pivotal directions for future energy storage deployment. To address the complexities arising from the coupling of different time scales in optimizing energy storage capacity, this paper proposes a method for energy storage planning that accounts for power imbalance risks across multiple time scales. Initially, the Seasonal and Trend decomposition using the Loess (STL) decomposition method is utilized to temporally decouple actual operational data. Subsequently, power balance computations are performed based on the obtained data at various time scales to optimize the allocation of different types of energy storage capacities and assess the associated imbalance risks. Finally, the effectiveness of the proposed approach is validated through hourly applications using real-world data from a province in southern China over recent years.

Effects of species mixing on maximum size-density relationships in Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.)-dominated mixed forests converted from even-aged pure stands.

Density management is a key silvicultural tool in management programs that enhances compositional and structural diversity and hence forest growth during the conversion of even-aged pure stands into mixed forests. To determine the optimum stand density, a model of maximum size-density relationships was employed to explore the relationship of the self-thinning trajectory with growth, species mixing, latitude, and site conditions during the transition of even-aged pure Chinese fir stands to Chinese fir-dominated mixed forests using stochastic frontier analysis. Data were obtained from a total of 591 permanent plots located in Fujian, Jiangxi, Zhejiang, and Anhui provinces in southern China. The results showed that (1) the slope of the maximum size-density relationship of Chinese fir-dominated mixed forests increased and plateaued over time; (2) the slope of the maximum size-density relationship of Chinese fir-dominated mixed forests did not deviate from Reineke's assumed universal slope of -1.605; and (3) mixing proportion had a positive effect on maximum size-density relationships, and latitude and site conditions had the opposite effect on maximum size-density relationships. Our findings will provide valuable guidance for the forest management of areas in which even-aged pure stands are being converted to mixed forests (i.e., when broadleaved tree species are planted after thinning to improve overall stand density and promote stand growth).

First report of Root-Knot Nematode Meloidogyne enterolobii infecting coriander in Shaanxi, Northern China.

Coriander (Coriandrum sativum), which can be used for its root, stem, and leaf as both food and medicine (Prachayasittikul et al. 2018), is widely cultivated in China. The coriander cultivation area of Guanzhong region, including Xi' an, Xianyang, and Weinan, is 20 million m2, which accounts for 85.7% of the total cultivation area in Shaanxi. In September 2022, obvious galls were observed on the roots of coriander plants (cv. Xiaoye) growing in a field in Huyi District, Xi' an City (34°1'26.4"N, 108°31'58.8"E). The diseased plants did not show obvious above-ground symptoms. To identify the species, second-stage juveniles (J2s) and males were collected from soil in the root zone, and adult females were isolated from galls of diseased roots. The perineal patterns of adult females (n = 20) were round to oval, with high dorsal arches and no obvious lateral lines were observed. Morphological measurements of females (n = 20) included body length (L) = 682 ± 56 (554 to 780) μm, body width (BW) = 522 ± 45 (420 to 597) μm, stylet = 14.9 ± 0.9 (13.4 to 16.3) μm, dorsal pharyngeal gland orifice to stylet base (DGO) = 5.3 ± 0.5 (4.3 to 6.3) μm, vulval slit length = 26 ± 2.8 (20 to 32) μm, vulval slit to anus distance = 21 ± 1.7 (18.5 to 26) μm. Measurements of males (n = 8) were L = 1398 ± 57 (1308 to 1450) μm, BW = 28 ± 2.9 (23 to 32) μm, stylet = 16.1 ± 0.8 (15.3 to 17.3) μm, DGO = 4.5 ± 0.5 (3.5 to 4.9) μm, spicules = 27 ± 1.1 (26 to 29) μm. Measurements of J2s (n = 20) were as follows: L = 434 ± 16.8 (391 to 477) μm, BW = 15.6 ± 0.9 (13.7 to 17.3) μm, stylet = 12.6 ± 0.6 (11.3 to 13.6) μm, DGO = 3.9 ± 0.3 (3.4 to 4.5) μm, tail = 52 ± 4.0 (47 to 60) μm, hyaline tail length = 15.6 ± 1.3 (13.6 to 18.6) μm. These morphological characteristics were consistent with those described for Meloidogyne enterolobii (Yang and Eisenback 1983). Ten females were put in 10 tubes for DNA extraction following Htay et al. (2016). The ITS-rDNA sequence was amplified using the primers 18S/26S (Vrain et al. 1992). A 765 bp fragment was obtained and the sequence (GenBank OR789453) was 99.87% identical to sequences of M. enterolobii (MT406251 and MT067559). The mtDNA CoxII-16S sequence was amplified using primers C2F3/1108 (Powers and Harris, 1993). The sequence was 705 bp (OR795028) and 100% identical to sequences of M. enterolobii (MK455870 and MZ643270). A single 236 bp fragment was amplified using species-specific primers Me-F/Me-R, confirming the species as M. enterolobii (Long et al. 2006). The infection test was conducted in a greenhouse at 27 ± 2℃. Eight 2-week-old coriander plants (cv. Xiaoye) were individually grown in pots filled with sterilizer soil and inoculated with 800 J2s hatched from collected M. enterolobii egg masses. Forty-five days after nematode inoculation, the inoculated plants had galled roots like those observed in the field. The reproduction factor (final population density/initial population density) was 11.9 ± 2.0, indicating coriander was a suitable host for M. enterolobii. No symptoms were observed in controls. To our knowledge, this is the first known natural infection of coriander with M. enterolobii in China. M. enterolobii has been reported on various crops in southern provinces of China (EPPO, 2023). Considering the high level of agricultural trade between different regions, there is a high risk of M. enterolobii transmission to Guanzhong region through infested soil and susceptible plant materials. Further monitoring and research on effective control strategies are needed to prevent the spread of this nematode.

Epidemiological monitoring and genetic variation analysis of pathogens associated with porcine viral diarrhea in southern China from 2021 to 2023.

Large-scale outbreaks of virus-associated severe diarrhea have occurred in pig populations since 2010. To investigate the prevalence and genetic evolution of the diarrhea-associated viruses responsible for the outbreaks, we tested 1,791 diarrhea samples collected from 213 pig farms in five provinces in southern China between 2021 and 2023. The test results showed that porcine epidemic diarrhea virus (PEDV) was the most frequently detected virus. The prevalence rates ranged from 47.40 to 52.22% in samples and 76.06% (162/213) in pig farms. Porcine rotavirus (PoRV) was the second common virus, with prevalence rates ranging from 25.81 to 50.81% in samples and 72.77%(155/213) in pig farms. Porcine delta coronavirus (PDCoV) was the third common virus, with prevalence rates ranging from 16.33 to 17.48% in samples and 38.50% (82/213) in pig farms. The detection rates of both transmissible gastroenteritis virus (TGEV) and porcine acute diarrheal syndrome coronavirus (SADS-CoV) were very low, less than 1.01% in samples and less than 3.76% in pig farms. In this study, we found SADS-CoV only in piglet diarrhea samples from Jiangxi, Guangdong, and Guangxi provinces in China, with a prevalence rate of 5.16% (11/213) in pig farms. Co-infection with these diarrhea-associated viruses is a common occurrence. The most common co-infections were PEDV and PoRV, with a prevalence rate of 6.64% (119/1,791), followed by PDCoV and PoRV, with a prevalence rate of 4.19% (75/1,791). Phylogenetic analyses showed that PEDV and PEDV variants prevalent in southern China during the past three years clustered into genotype GIIb and recombinant PEDV subtypes. Among the currently endemic PEDV, the most common mutations occurred in the collagenase equivalent (COE) and epitope regions of the spike gene. PoRV strains were mainly dominated by the G9 subtype, followed by the G5, G3 and G4 subtypes. Our results suggest that variant PEDV, PDCoV and PoRV are the main pathogens of swine diarrhea, and singular- or co-infection with pathogenic enteric CoV is common in pig herds in southern China. Therefore, prevention and control of porcine viral diarrhea should be given high attention.

Colletotrichum Species Causing Cyclocarya paliurus Anthracnose in Southern China

Cyclocarya paliurus, native to China, is a medicinal and edible plant with important health benefits. Anthracnose is an emerging disease in southern China that causes severe economic losses and poses a great threat to the C. paliurus tea industry. However, to date, the species diversity of pathogens causing C. paliurus anthracnose has remained limited. From 2018 to 2022, a total of 331 Colletotrichum isolates were recovered from symptomatic leaves in eight major C. paliurus planting provinces of southern China. Phylogenetic analyses based on nine loci (ITS, GAPDH, ACT, CHS-1, TUB, CAL, HIS3, GS and ApMat) coupled with phenotypic characteristics revealed that 43 representative isolates belonged to seven known Colletotrichum species, including C. brevisporum, C. fructicola, C. gloeosporioides sensu stricto, C. godetiae, C. nymphaeae, C. plurivorum and C. sojae. Pathogenicity tests demonstrated that all species described above were pathogenic to wounding detached leaves of C. paliurus, with C. fructicola being the most aggressive species. However, C. brevisporum, C. plurivorum and C. sojae were not pathogenic to the intact plant of C. paliurus. These findings reveal the remarkable species diversity involved in C. paliurus anthracnose and will facilitate further studies on implementing effective control of C. paliurus anthracnose in China.

The interactions between ineffective erythropoiesis and ferroptosis in β-thalassemia.

In Guangxi, Hainan, and Fujian Province in southern China, β-thalassemia is a frequent monogenic hereditary disorder that is primarily defined by hemolytic anemia brought on by inefficient erythropoiesis. It has been found that ineffective erythropoiesis in β-thalassemia is closely associated with a high accumulation of Reactive oxygen species, a product of oxidative stress, in erythroid cells. During recent years, ferroptosis is an iron-dependent lipid peroxidation that involves abnormalities in lipid and iron metabolism as well as reactive oxygen species homeostasis. It is a recently identified kind of programmed cell death. β-thalassemia patients experience increased iron release from reticuloendothelial cells and intestinal absorption of iron, ultimately resulting in iron overload. Additionally, the secretion of Hepcidin is inhibited in these patients. What counts is both ineffective erythropoiesis and ferroptosis in β-thalassemia are intricately linked to the iron metabolism and Reactive oxygen species homeostasis. Consequently, to shed further light on the pathophysiology of β-thalassemia and propose fresh ideas for its therapy, this paper reviews ferroptosis, ineffective erythropoiesis, and the way they interact.

How Does Land Fragmentation Affect Agricultural Technical Efficiency? Based on Mediation Effects Analysis

The scientific revelation of the mechanism underlying land fragmentation’s influence on agricultural technical efficiency is extremely important. This study utilized survey data from 305 villages across 12 provinces in Southern China in 2020 to assess technical efficiency through the application of the stochastic frontier production function. Moreover, we investigated the direct impact of land fragmentation on technical efficiency and the indirect impact transmitted through crop diversification and part-time farming by employing Tobit and mediating effect models, respectively. The key findings are as follows: (1) The sampled farmers, on average, operated 0.614 hectares of land with 17.395 plots, and the mean of their technical efficiency was 0.630. (2) The overall effect of land fragmentation on technical efficiency demonstrated a “U”-shaped relationship. (3) Crop diversification and part-time farming were mediating factors in the impact of land fragmentation on technical efficiency. Specifically, an “inverted U”-shaped relationship existed between land fragmentation and crop diversification, whereas a negative linear relationship was observed between land fragmentation and part-time farming. Conversely, crop diversification presented a positive linear relationship with technical efficiency, and part-time farming had an “inverted U”-shaped relationship with technical efficiency. (4) The impact of land fragmentation on technical efficiency varied across altitude zones. It is recommended to control land fragmentation based on local conditions, encourage crop diversification, and strengthen employment guidance and skills training for farmers to ensure the orderly transfer of land.

Genetic and Evolutionary Analysis of Porcine Deltacoronavirus in Guangxi Province, Southern China, from 2020 to 2023.

Porcine deltacoronavirus (PDCoV) has shown large-scale global spread since its discovery in Hong Kong in 2012. In this study, a total of 4897 diarrheal fecal samples were collected from the Guangxi province of China from 2020 to 2023 and tested using RT-qPCR. In total, 362 (362/4897, 7.39%) of samples were positive for PDCoV. The S, M, and N gene sequences were obtained from 34 positive samples after amplification and sequencing. These PDCoV gene sequences, together with other PDCoV S gene reference sequences from China and other countries, were analyzed. Phylogenetic analysis revealed that the Chinese PDCoV strains have diverged in recent years. Bayesian analysis revealed that the new China 1.3 lineage began to diverge in 2012. Comparing the amino acids of the China 1.3 lineage with those of other lineages, the China 1.3 lineage showed variations of mutations, deletions, and insertions, and some variations demonstrated the same as or similar to those of the China 1.2 lineage. In addition, recombination analysis revealed interlineage recombination in CHGX-MT505459-2019 and CHGX-MT505449-2017 strains from Guangxi province. In summary, the results provide new information on the prevalence and evolution of PDCoV in Guangxi province in southern China, which will facilitate better comprehension and prevention of PDCoV.

Sustainable energy development of crop straw in five southern provinces of China: Bioenergy production, land, and water saving potential

Crop straw, a renewable resource, holds a crucial position in transition towards alternative, clean bioenergy. However, there is a dearth of analysis on the land- and water-saving potential associated with producing bioenergy from crop straw instead of clean energy. To comprehensively address these deficiencies, we conducted a face-to-face field survey for deep analysis. Our results revealed that most crop straw in the five southern provinces of China is retained in the field or openly burned, less for energy utilization. However, we also found that promoting bioenergy production potential from crop straw is significant and could meet the current energy demand for transportation or households in the five southern provinces. The production of briquette fuel and bioethanol from crop straw can significantly reduce GHG emissions of 23.3 Mton and 23.2 Mton, respectively, compared with coal and gasoline consumption. Furthermore, our study illustrated that replacing energy crops like Jerusalem artichoke with crop straw to produce bioethanol could reduce 11% of the total sown area occupied and save 3% of the irrigation water used in the five provinces. In conclusion, this study offers a more sustainable and efficient approach to producing bioethanol and other bioenergy while minimizing environmental impact and reducing resource consumption.

Identification of a novel adenovirus in liver tissue sample of the Great Himalayan leaf-nosed bat (Hipposideros armiger).

Bats are important reservoirs for many zoonotic viruses. To explore and monitor potential novel viruses carried by bats, 21 liver samples of bats (Hipposideros armiger) were collected from Yunnan Province in southern China. Only one (4.8%) of all models was detected with adenovirus. The whole genome strain obtained by the viral metagenomics method combined with PCR was temporarily named YN01. The complete genome of YN01 was 37,676bp, with a G + C content of 55.20% and 28 open reading frames. Phylogenetic analysis indicated that the strain YN01 can be classified as genus Mastadenovirus and was the most similar to the adenovirus isolated from Rhinolophus sinicus in China in 2016. The analysis is needed to verify the possibility of cross-species transmission. This virological investigation has increased our understanding of the ecology of bat-borne viruses in this area and provided a reference for possible future infectious diseases.

Seasonal prediction of the distribution of three major malaria vectors in China: Based on an ecological niche model.

Against the backdrop of a global malaria epidemic that remains severe, China has eradicated indigenous malaria but still has to be alert to the risk of external importation. Understanding the distribution of vectors can provide an adequate and reliable basis for the development and implementation of vector control strategies. However, with the decline of malaria prevalence in recent years, the capacity of vector monitoring and identification has been greatly weakened. Here we have used new sampling records, climatic data, and topographic data to establish ecological niche models of the three main malaria vectors in China. The model results accurately identified the current habitat suitability areas for the three species of Anopheles and revealed that in addition to precipitation and temperature as important variables affecting the distribution of Anopheles mosquitoes, topographic variables also influenced the distribution of Anopheles mosquitoes. Anopheles sinensis is the most widespread malaria vector in China, with a wide region from the northeast (Heilongjiang Province) to the southwest (Yunnan Province) suitable for its survival. Suitable habitat areas for Anopheles lesteri are concentrated in the central, eastern, and southern regions of China. The suitable habitat areas of Anopheles minimus are the smallest and are only distributed in the border provinces of southern China. On this basis, we further assessed the seasonal variation in habitat suitability areas for these three major malaria vectors in China. The results of this study provide new and more detailed evidence for vector monitoring. In this new era of imported malaria prevention in China, regular reassessment of the risk of vector transmission is recommended.

Tracking the carbon flows in municipal waste management in China

Municipal solid waste (MSW), a carbon-intensive waste stream, may create both instant and indirect impacts onto environmental and climate management. Despite multiple studies made for greenhouse gases (GHGs) emissions of municipal waste, this research aims to achieve a comprehensive assessment for the carbon cycle by exploring evolution of waste composition and temporal-spatial disparities in waste management. Carbon flows embodied in MSW have been estimated across 31 provinces in Mainland China in the period 2000–2018. This improved estimation could be 15–40% smaller than the conventional estimation employing a constant waste composition. Aggregately some 578 ± 117 megatonnes carbon (MtC) were contained in MSW, including 239 ± 60 Mt of fossil carbon and 339 ± 58 Mt of degradable organic carbon. After treatment, 299 ± 66 MtC were possibly deposited in landfills and dumps. 279 ± 51 MtC were released to the atmosphere, creating net GHGs emissions equivalent to1870 ± 334 megatonnes of CO2 (MtCO2e). MSW generation in China nearly doubled during the period, net GHGs emissions increased by 1.8×, whereas fossil carbon grew by a factor of 3.5, mainly propelled by an increasing content of waste plastic in MSW. More rapid growth was witnessed in provinces in southern China than in northern. Distinct spatial–temporal evolution of waste and carbon metabolism was driven by increment, composition, and management effects. In the long run, the increment and composition effects may drop off. Enhanced practices of waste management integrating the circular economy are needed to fully recycle carbon flows, minimize emissions, and manage carbon deposits in aging landfills and dumps.

Prevalence and phylogenetic analysis of Gyrovirus galga 1 in southern China from 2020 to 2022

Since 2011, the Gyrovirus galga 1 (GyVg1, previously recognized as avian gyrovirus 2) strain has extensively been detected worldwide. However, because there are no up-to-date reports of examining the distribution of GyVg1 in flocks in southern China, the epidemiology of this virus is unknown. To investigate the prevalence and genetic evolution of GyVg1, a total of 2,077 field samples collected from 113 chicken farms in 6 provinces in southern China during 2020 to 2022 were tested. Among them, 315 samples (315/2,077, 15.17%) were positive for GyVg1 by PCR. The positive rate of GyVg1 detection between different regions of southern China ranged from 11.69% (Guangdong) to 22.46% (Yunnan). The correlation between GyVg1 prevalence and sample source groups was analyzed, the results showing that the highest seroprevalence of GyVg1 was observed in visceral tissues (27.34%, 187/684), significantly higher (P < 0.05) than that of feather shafts (17.22%, 31/180), serums (8.85%, 78/881), and fecal (5.72%, 19/332). Additionally, the complete genomes of 10 GyVg1 strains were sequenced and analyzed, which showed nucleotide identities of 96.2 to 99.9%, 97.0 to 100.0%, 95.2 to 100.0%, and 95.7 to 99.8% in the complete genome, ORF1, ORF2, and ORF3, respectively, and 94.4 to 100.0%, 91.3 to 100.0%, and 98.7 to 100.0% amino acid similarity in the VP2, VP3, and VP1 proteins, respectively. Phylogenetic analysis of the whole genome showed that 10 GyVg1 strains belong to genotype I, and one strain belongs to genotype III. Sequence analysis showed several amino acid substitutions in both the VP1, VP2, and VP3 proteins. Our results enhance the understanding of the molecular characterization of GyVg1 infection in southern China. In conclusion, this study reveals the high prevalence and high genetic differentiation of GyVg1 in Chinese chickens and suggests that the potential impact of GyVg1 on the chicken industry may be of concern.

A novel bivalent inactivated vaccine for ducks against Riemerella anatipestifer based on serotype distribution in southern China

Riemerella anatipestifer (RA) causes epizootic infectious polyserositis in ducks with high mortality and leads to huge economic losses worldwide. Bacterial resistance poses a challenge for the control of the disease, vaccines failed to provide ideal cross-protection. Thus, the preparation of vaccines based on popular serotypes is important. In this study, we collected 700 brain and liver tissues of dead ducks from 8 provinces in southern China from 2016 to 2022 and obtained 195 RA isolates with serotypes 1, 2, 7, and 10. Serotypes 1 and 2 were the most prevalent (82%). A novel bivalent inactivated vaccine WZX-XT5 containing propolis adjuvant was prepared, we chose XT5 (serotype 1) and WZX (serotype 2) as vaccine strains and evaluated WZX-XT5-induced immune response and protective efficacy in ducks. Results showed that the XT5 (LD50, 3.5 × 103 CFU) exhibited high virulence and provided better protection against RA compared with ZXP, DCR and LCF1 (LD50, 108 CFU). Notably, the dose of 109 CFU provided ideal protection compared with 108 CFU, propolis and oil emulsion adjuvants induced stronger protective efficacy compared with aluminum hydroxide adjuvant. Importantly, WZX-XT5 immunization induced high levels of RA-specific IgY, IFN-γ, IL-2, and IL-4 in serum and offered over 90% protection against RA with ultra-high lethal dose in ducks. Additionally, no clinical signs of RA infection or obvious pathological damage in tissues were observed in protected ducks. Overall, this study first reports the identification, serotyping and virulence of RA in ducks of southern China and the preparation of a novel bivalent inactivated vaccine, providing useful scientific information to prevent and control RA infection.

Factors Associated with the First-time HIV Testing Among Chinese men who have sex with men Who Received HIV Self-tests from Partners or Friends.

Secondary distribution of HIV self-testing (HIVST) among individual social networks was an effective approach to expanding HIV testing among men who have sex with men (MSM). However, understanding the factors associated with first-time HIV testing behaviors in the secondary distribution of HIVST programs is limited. Hence, this study aims to identify factors related to first-time testers in the secondary distribution of HIVST. Participants were recruited from five provinces in southern China through Blued, a geo-social gay networking app in China from January 2021 to December 2021. Eligible consented participants (referred to as "seeds") finished a baseline survey and then applied for up to five HIVST kits. They were encouraged to distribute HIVST kits to other MSM (referred to as "alters") and alters were encouraged to scan a QR code to return their photographed testing results. All alters were invited to finish an online survey. In total, 229 seeds reached 292 alters, among whom 126 (43.2%) were first-time testers whereas 166 (56.8%) were non-first-time testers. Importantly, our results demonstrated that the first-time HIV testers were more likely to self-report as heterosexual (aOR = 4.88, 95% CI 1.01-23.61), disclose sexual orientation and/or SSB (aOR = 1.73, 95% CI 1.01-2.96), and receive HIVST knowledge from the seeds (aOR = 3.25, 95% CI 1.02-10.34). However, those who had sex with male partners in the last three months were less likely to be first-time testers (aOR = 0.43, 95% CI 0.23-0.82). Practical implications and limitations were also discussed to improve future HIV prevention programs.

Enhanced MRI Radiomics Based Model for Predicting Recurrence or Metastasis of Nasopharyngeal Cancer (NC) Undergoing Concurrent Chemoradiotherapy: A Retrospective Study.

Nasopharyngeal Carcinoma (NC) refers to the malignant tumor that occurs at the top and side walls of the nasopharyngeal cavity. The NC incidence rate always dominates the first among the malignant tumors of the ear, nose and throat, and mainly occurs in Asia. NC cases are mainly concentrated in southern provinces in China, with about 4 million existing NC. With the pollution of environment and pickled diet, and the increase of life pressure, the domestic NC incidence rate has reached 4.5-6.5/100000 and is increasing year by year. It was reported that the known main causes of NC include hereditary factor, genetic mutations, and EB virus infection, common clinical symptoms of NC include nasal congestion, bloody mucus, etc. About 90% of NC is highly sensitive to radiotherapy which is regard as the preferred treatment method; However, for NC with lower differentiation, larger volume, and recurrence after treatment, surgical resection and local protons and heavy ions therapy are also indispensable means. According to reports, the subtle heterogeneity and diversity exists in some NC, with about 80% of NC undergone radiotherapy and about 25% experienced recurrence and death within five years after radiotherapy in China. Therefore, screening the NC population with suspected recurrence after concurrent chemoradiotherapy may improve survival rates in current clinical decision-making.

&amp;#8220;I&amp;#8217;ll be back&amp;#8221;: the emergence of recentralized forest devolution in the southern provinces of China

&amp;#8220;I&amp;#8217;ll be back&amp;#8221;: the emergence of recentralized forest devolution in the southern provinces of China