Different Geographical Locations In China Research Articles

Carbon-oriented energy system planning using forest carbon sink

More than 130 countries and regions have put forward various climate goals, which makes carbon-oriented energy system planning a heated topic. However, these planning studies do not consider the carbon fixation role played by forest carbon sinks (FCSs). To take advantage of the carbon fixation role of FCSs, this paper will develop a carbon-cycle integrated energy hub (CC-EH) model to quantify the economic advantages of FCSs in planning a zero-carbon energy system, where energy flow and carbon flow are both analyzed. A total planning and operating costs minimization with the constraints of CO2 emissions is proposed as a mixed integer nonlinear programming (MINLP) optimization model and the overall problem is solved based on commercial solver. The proposed model is validated by case studies on six medium to large-size cities in different geographical locations in China. Results indicate that the typical cities in China can fulfill their carbon-neutral commitments by 2060. Throughout the entire planning period, FCSs can offset up to 55.31 % of the total carbon dioxide emissions from urban energy systems. Besides, FCSs achieved by forestation will help the energy system to reduce up to 36 % of the planning cost compared to the case without using FCSs.

Impact of R&D and innovation in Chinese road transportation sustainability performance: A novel trigonometric envelopment analysis for ideal solutions (TEA-IS)

Previous road transportation sustainability studies not only neglected the epistemic uncertainty that surrounds the impact of innovation and Research and Development (R&D) expenditure on pollutant emissions performance but also failed in designing and simultaneously exploring the strengths of alternative MCDM (Multiple-Criteria Decision-Making) approaches to better discriminate performance scores. This paper focuses on these two gaps by presenting a road transportation sustainability performance assessment of 29 Chinese provinces for a 14-year period in light of relevant socioeconomic and demographic variables. First, a novel TEA-IS model is developed to assess road transportation sustainability performance. Besides possessing the beneficial features of each model, this hybrid DEA-TOPSIS can analyze the sustainability performance from the perspective of the synergistic effects among the criteria. From the socioeconomic and demographic perspectives, we use machine learning techniques for predicting high-low performance and synergistic Chinese provinces. Results suggest that the discriminatory power of TEA-IS is good and there is high synergy in Chinese provinces in terms of sustainable road transportation. We further find that there is a high level of heterogeneity in road transportation sustainability among different geographical locations in China. The results further suggest that higher levels of synergy are strongly associated with medium and high-performing provinces. Finally, we find that innovation index, foreign direct investment, and non-coastal cities have both higher performance and synergy levels. We recommend that Chinese government should further provide favorable policies to enhance innovation and efforts should also be made to provide better environment for attracting more foreign direct investment. Finally, instead of road transportation, other modes of transportation, such as air and sea, are recommended to be further developed and utilized.

Antibiotic resistance, virulence and genetic characteristics of Vibrio alginolyticus isolates from aquatic environment in costal mariculture areas in China.

Vibrio alginolyticus has been the second most common Vibrio species in the world and mainly grows in the ocean or estuary environment, which can induce epidemics outbreaks under marine organisms, and causing serious economic losses in aquaculture industry. In this study, the genetic populations and evolutionary relationship analysis of V. alginolyticus isolated from different geographical locations in China with typical interannual differences were exhibited originally genetic diversity. Then the virulence genes prevalence, antibiotic resistance phenotype, and antimicrobial resistance genes risk diversity of V. alginolyticus were analyzed by phenotypic and molecular typing methods. And they were complex correlations among antibiotic phenotypes, resistance and virulence genes under different genotype of V. alginolyticus. The results provide a theoretical foundation for further understanding the genetic and metabolic diversity among V. alginolyticus in China, and lay a theoretical foundation for the transmission risk assessment and regional diagnosis of Vibrio in aquatic animals.

Using Ex Situ Seedling Baiting to Capture Seedling-Associated Mycorrhizal Fungi in Medicinal Orchid Dendrobium officinale.

Using orchid mycorrhizal fungi (OMFs) to facilitate orchid proliferation is considered an effective method of orchid conservation. Based on the success of using in situ seedling baiting to obtain plant growth-promoting fungi in our previous study, in this study, we developed the method of using ex situ seedling baiting to capture seedling-associated fungi from Dendrobium officinale. We collected substrates (e.g., litters, barks and mosses) from six original habitats of D. officinale in different geographical locations in China, and then, transplanted in vitro-produced seedlings of D. officinale into the substrates. After cultivation for 75 days, it was obvious that fungi colonized the seedling roots and formed large numbers of pelotons in all six groups. From these seedling roots, a total of 251 fungal strains, which were divided into 16 OMF and 11 non-OMF species, were successfully isolated. The 16 OMFs included 13 Tulasnella and 3 Serendipitaceae species. The fungal species isolated from the different groups (original habitat sources) were not identical, but the dominant OMFs with high isolation frequencies (more than 10 times) were commonly isolated from more than four original sources. Among the 11 non-OMFs, Fusarium oxysporum TP-18 and Muscodor sp. TP-26 were the dominant endophytes. Fusarium oxysporum is a common endophyte associated with many orchid species, including D. officinale. The results suggest that ex situ seedling baiting is an easy and efficient approach to obtaining seedling-associated fungi for this species and could be performed for other over-collected species, especially orchids for which wild plants have disappeared in the field but their original habitats are known. This approach has great potential for application in OMF studies in the future.

Ecological niche modeling based on ensemble algorithms to predicting current and future potential distribution of African swine fever virus in China

African swine fever (ASF) is a tick-borne infectious disease initially described in Shenyang province China in 2018 but is now currently present nationwide. ASF has high infectivity and mortality rates, which often results in transportation and trade bans, and high expenses to prevent and control the, hence causing huge economic losses and a huge negative impact on the Chinese pig farming industry. Ecological niche modeling has long been adopted in the epidemiology of infectious diseases, in particular vector-borne diseases. This study aimed to establish an ecological niche model combined with data from ASF incidence rates in China from August 2018 to December 2021 in order to predict areas for African swine fever virus (ASFV) distribution in China. The model was developed in R software using the biomod2 package and ensemble modeling techniques. Environmental and topographic variables included were mean diurnal range (°C), isothermality, mean temperature of wettest quarter (°C), precipitation seasonality (cv), mean precipitation of warmest quarter(mm), mean precipitation of coldest quarter (mm), normalized difference vegetation index, wind speed (m/s), solar radiation (kJ /day), and elevation/altitude (m). Contribution rates of the variables normalized difference vegetation index, mean temperature of wettest quarter, mean precipitation of coldest quarter, and mean precipitation of warmest quarter were, respectively, 47.61%, 28.85%, 10.85%, and 7.27% (according to CA), which accounted for over 80% of contribution rates related to variables. According to model prediction, most of areas revealed as suitable for ASF distribution are located in the southeast coast or central region of China, wherein environmental conditions are suitable for soft ticks’ survival. In contrast, areas unsuitable for ASFV distribution in China are associated with arid climate and poor vegetation, which are less conducive to soft ticks’ survival, hence to ASFV transmission. In addition, prediction spatial suitability for future ASFV distribution suggests narrower areas for ASFV spread. Thus, the ensemble model designed herein could be used to conceive more efficient prevention and control measure against ASF according to different geographical locations in China.

Prevalence of antifolate drug resistance markers in Plasmodium vivax in China.

The dihydrofolate reductase (dhfr) and dihydropteroate synthetase (dhps) genes of Plasmodium vivax, as antifolate resistance-associated genes were used for drug resistance surveillance. A total of 375 P. vivax isolates collected from different geographical locations in China in 2009-2019 were used to sequence Pvdhfr and Pvdhps. The majority of the isolates harbored a mutant type allele for Pvdhfr (94.5%) and Pvdhps (68.2%). The most predominant point mutations were S117T/N (77.7%) in Pvdhfr and A383G (66.8%) in Pvdhps. Amino acid changes were identified at nine residues in Pvdhfr. A quadruple-mutant haplotype at 57, 58, 61, and 117 was the most frequent (57.4%) among 16 distinct Pvdhfr haplotypes. Mutations in Pvdhps were detected at six codons, and the double-mutant A383G/A553G was the most prevalent (39.3%). Pvdhfr exhibited a higher mutation prevalence and greater diversity than Pvdhps in China. Most isolates from Yunnan carried multiple mutant haplotypes, while the majority of samples from temperate regions and Hainan Island harbored the wild type or single mutant type. This study indicated that the antifolate resistance levels of P. vivax parasites were different across China and molecular markers could be used to rapidly monitor drug resistance. Results provided evidence for updating national drug policy and treatment guidelines.

Latitudinal difference in the molecular distributions of lipid compounds in the forest atmosphere in China

Lipids are important biogenic markers to indicate the sources and chemical process of aerosol particles in the atmosphere. To better understand the influences of biogenic and anthropogenic sources on forest aerosols, total suspended particles (TSP) were collected at Mt. Changbai, Shennongjia, and Xishuangbanna that are located at different climatic zones in northeastern, central and southwestern China. n-Alkanes, fatty acids and n-alcohols were detected in the forest aerosols based on gas chromatography-mass spectrometry. The total concentrations of aliphatic compounds ranged from 15.3 ng m−3 to 566 ng m−3, and fatty acids were the most abundant (44–95%) followed by n-alkanes and n-alcohols. Low molecular weight- (LFAs) and unsaturated fatty acids (UnFAs) showed diurnal variation with higher concentrations during the nighttime in summer, indicating the potential impact from microbial activities on forest aerosols. The differences of oleic acid (C18:1) and linoleic acid (C18:2) concentrations between daytime and nighttime increased at lower latitude, indicating more intense photochemical degradation occurred at lower latitude regions. High levels of n-alkanes during daytime in summer with higher values of carbon preference indexes, combining the strong odd carbon number predominance with a maximum at C27 or C29, implied the high contributions of biogenic sources, e.g., higher plant waxes. In contrast, higher concentrations of low molecular weight n-alkanes were detected in winter forest aerosols. Levoglucosan showed a positive correlation (R2 > 0.57) with high- and low molecular weight aliphatic compounds in Mt. Changbai, but such a correlation was not observed in Shennongjia and Xishuangbanna. These results suggest the significant influence of biomass burning in Mt. Changbai, and fossil fuel combustion might be another important anthropogenic source of forest aerosols. This study adds useful information to the current understanding of forest organic aerosols at different geographical locations in China.

Environmental factors shape the epiphytic bacterial communities of Gracilariopsis lemaneiformis

Macroalgae host various symbionts on their surface, which play a critical role in their growth and development processes. However, there is still incomplete understanding of this epiphytic bacteria-host algae interactions. This study comprehensively analysed variation of the epiphytic bacterial communities (EBC) composition of red macroalga Gracilariopsis lemaneiformis at different geographic locations and environmental factors (i.e., nitrogen and phosphorus), which shape the EBC composition of G. lemaneiformis. The composition and structure of EBC were characterized using high throughput sequencing of the V3-V4 hypervariable region of the 16S rRNA gene. The results revealed that epiphytic bacteria varied significantly among three different geographic locations in China, i.e., Nan’ao Island (NA), Lianjiang County (LJ), and Nanri Island (NR). Redundancy analysis (RDA) showed that the relative abundance of Bacteroidetes, Firmicutes, Verrucomicrobia, and Epsilonbacteraeota at NR were strongly positively correlated with total nitrogen (TN), total phosphorus (TP), nitrate nitrogen (NO3-N), and dissolved inorganic nitrogen (DIN), but negatively correlated with nitrite nitrogen (NO2-N). The relative abundance of Cyanobacteria at NA and LJ were strongly positively correlated with NO2-N, but negatively correlated with TN, TP, NO3-N, and DIN. Besides, the Mantel test results indicated that the EBC composition was significantly correlated with these environmental factors, which was also confirmed by Spearman correlation analysis. Thus, environmental factors such as NO3-N and DIN play a key role in the community composition of epiphytic bacteria on G. lemaneiformis. This study provides important baseline knowledge on the community composition of epiphytic bacteria on G. lemaneiformis and shows correlation between different epiphytic bacteria and their surrounding environmental factors.

Latitudinal Difference in the Molecular Distributions of Lipid Compounds in the Forest Atmosphere in China

Lipids are important biological markers to indicate the sources and chemical process of aerosol particles in the atmosphere. To better understand the influences of biological and anthropogenic sources on forest aerosols, total suspended particles (TSP) were collected at Mt. Changbai, Shennongjia, and Xishuangbanna that are located at different climatic zones in northeastern, central and southwestern China. n-Alkanes, fatty acids and n-alcohols were detected in the forest aerosols based on gas chromatography-mass spectrometry. The total concentrations of aliphatic compounds ranged from 33.2 ng m-3 to 520 ng m-3, and fatty acids were the most abundant (44-95%) followed by n-alkanes and n-alcohols. Low molecular weight- (LFAs) and unsaturated fatty acids (UnFAs) showed diurnal variation with higher concentrations during the nighttime in summer, indicating the potential impact from microbial activities on forest aerosols. The differences of oleic acid (C18:1) and linoleic acid (C18:2) concentrations between daytime and nighttime increased at lower latitude, indicating more intense photochemical degradation occurred at lower latitude regions. High levels of n-alkanes during daytime in summer with higher values of carbon preference indexes, combining the strong odd carbon number predominance with a maximum at C27 or C29, implied the high contributions of biological sources, e.g., higher plant waxes. In contrast, higher concentrations of low molecular weight n-alkanes were detected in winter forest aerosols. Levoglucosan showed a positive correlation (R2>0.57) with high- and low molecular weight aliphatic compounds in Mt. Changbai, but such a correlation was not observed in Shennongjia and Xishuangbanan. These results suggest the significant influence of biomass burning in Mt. Changbai, and fossil fuel combustion might be another important anthropogenic source in Northeast China. This study adds useful information to the current understanding of forest organic aerosols at different geographical locations in China.

Positioning Performance Comparison Between GPS and BDS With Data Recorded at Four MGEX Stations

In December 2018, the BeiDou III (BDS-3) basic system was completed and began to provide global services. along with the BeiDou second-generation satellite navigation system (BDS-2) and Beidou first-generation satellite navigation system (BDS-1), the whole BDS has advantages in the number of satellites, coverage, and positioning performance. This paper focuses on the comprehensive evaluation of BDS by comparing the data quality and positioning performance of BDS and those of Global Positioning System (GPS). The performance evaluation and comparison is based on 7-day observation data collected in April 2020 at three different geographical locations in China. The experimental results show that GPS and BDS have a number of significant differences. The number of visible satellites in BDS is twice that of GPS in China. The SNRs of GPS signals of different frequencies are quite different from each other, while BDS signals of different frequencies have very similar SNR observations. BDS-3 and GPS achieve similar positioning performance in terms of internal positional error, external positional accuracy, coordinate time series and Dilution of Precision (DOP). The mean and STD of the internal positional error of GPS and BDS are less than 3 m, while the external positional accuracy of both systems is better than 5 m. It is also observed that the overall variation in coordinate time series of the three coordinates of BDS is slightly smaller than that of GPS. In addition, the BDS DOP is basically equivalent to the GPS DOP, although occasionally the former is greater than the latter. The results are largely contrary to most of the results associated with performance comparison between BDS and GPS reported in the literature. The main reason would be that the number of visible satellites, observations and DOP of BDS are superior to GPS and single BDS-1, BDS-2 or BDS-3 in China. We believe that the development of BDS is still in progress and BDS is making continuous performance enhancement.

Genotyping and Phylogenetic Position of Trichinella spiralis Isolates from Different Geographical Locations in China.

In China, the nematode Trichinella spiralis is the main aetiological agent of human trichinellosis. We performed multi-locus microsatellite typing of T. spiralis isolates to improve the current knowledge of the evolution and population diversity. First, seven polymorphic microsatellite loci were used to infer the genetic diversity of T. spiralis collected in 10 endemic regions. Then, a Bayesian model-based STRUCTURE analysis, a clustering based on the neighbor-joining method, and a principal coordinate analysis (PCA) were performed to identify the genetic structure. Finally, the phylogenetic position of Chinese isolates was explored based on six mitochondrial and nuclear genetic markers (cox1, cytb, 5S ISR, ESV, ITS1, and 18S rDNA) using the maximum likelihood and Bayesian methods. In addition, the divergence time was estimated with multiple genes using an uncorrelated log-normal relaxed molecular-clock model. A total of 16 alleles were detected in 2,310 individuals (1,650 muscle larvae and 660 adult worms) using seven loci. The STRUCTURE analysis indicated that the T. spiralis isolates could be organized and derived from the admixture of two ancestral clusters, which was also substantiated through the clustering analysis based on the allelic data. PCA separated most samples from Tiandong, Guangxi (GX-td), and Linzhi, Tibet (Tibet-lz), from the remaining isolates. However, both maximum likelihood and Bayesian inference supported the close relationship between Xiangfan, Hubei (HB-xf), and GX-td. The molecular dating analysis suggested that the Chinese isolates started to diverge during the Late Pleistocene (0.69 Mya). Generally, T. spiralis was observed to harbor low genetic variation, and further investigation with deeper sampling is needed to elucidate the population structure.

Multiple factors govern the biogeographic distribution of archaeal community in mangroves across China

Archaea can participate in the biogeochemical processes in mangrove ecosystem. The biogeographic distribution of archaeal community in mangroves remains poorly known. In this study, six mangroves at different geographic locations in China were selected. Mangrove archaeal community was found to considerably change with geographic location, which might be driven by a variety of environmental variables (etc., pH and carbon and nitrogen contents). Archaeal communities were primarily comprised of Thaumarchaeota (54.7–85.2%) and Euryarchaeota (11.8–43.9%). This work could provide some new insights towards the distribution of archaeal community in mangrove ecosystem.

High-Throughput Immunological Analysis of Dictamni Cortex: Implication in the Quality Control of Herbal Medicine.

Quality inconsistency of herbal medicine is an obstacle that limits the extensive use and study of traditional Chinese medicine. Differences in environmental conditions and processing methods of herbal medicine often result in varying clinical outcomes in patients. Standard chemical markers used for the quality control (QC) of herbal medicine are usually the most abundant and characteristic components, which may not be therapeutically relevant or cannot comprehensively reflect the biological quality of the herbs. In view of this, a novel QC method for better assessment of herbal medicine has been developed via bioactivities analysis. Immunological activities of Dictamni Cortex, a typical herbal medicine for the treatment of various inflammatory diseases, from different geographical locations in China, were evaluated. Upon in vitro treatment of their water and ethanol extracts, distinct patterns of inflammatory cytokines including tumor necrosis factor (TNF)-α, interleukin (IL)-10, IL-6, IL-12p70, IL-1β, and chemokine CXCL8 were released from the lipopolysaccharides- and/or phytohaemagglutinin-stimulated human peripheral blood mononuclear cells (PBMC). Thus, in addition to the commonly used morphological, chemical, or DNA markers, the novel high-throughput profiling of inflammatory cytokines and chemokines of PBMC upon treatment with herbal extracts could be an important reference to help for the quality control of herbal medicine in the future.

Prevalence and Population Genetics Analysis of Enterocytozoon bieneusi in Dairy Cattle in China.

Enterocytozoon bieneusi, an obligate intracellular pathogen, can infect various hosts. In this study, 3527 dairy cattle fecal specimens were collected from different geographic locations in China (including 673 from Shandong province, 1,440 from Guangdong province and 1,414 from Gansu province) and examined for the presence of E. bieneusi using polymerase chain reactions targeting the ribosomal internal transcribed spacer (ITS). The dominant genotypes identified were further subtyped by multilocus sequence typing. The overall prevalence of E. bieneusi was 14.2% (501/3527), with a significant difference in prevalence among the different geographical locations (P < 0.001). Our logistic regression analysis showed that all four variables (farming model, location, age, and clinical manifestations) had strong effects on the risk of contracting E. bieneusi. Sequence analysis revealed 11 genotypes: eight known genotypes (J, I, BEB4, BEB10, D, EbpC, CM19, and CM21) and three novel genotypes (named here as CGC1, CGC2, and CGC3). Genotypes J and I, the commonest, were found on all farms across the three provinces. Our linkage disequilibrium analysis showed a clonal population structure in the E. bieneusi dairy cattle population but the ITS genotypes had different population structures. Phylogenetic and haplotype network analysis showed the absence of geographical segregation in the E. bieneusi dairy cattle populations. Instead, they revealed the presence of host adaptation to the E. bieneusi populations in various animals. Our findings augment the current understanding of E. bieneusi transmission dynamics.

Telesupervision-of-supervision across national boundaries: United States and China.

This article describes technology-assisted telesupervision-of-supervision, which is a component of a 2-year U.S.-China collaborative program designed to systematically train clinical supervisors in China. Using Zoom conferencing platform, several U.S.-based supervisors facilitated telesupervision-of-supervision groups, with six to ten participants in each group, from different geographic locations in China. This article employs the perspectives of both U.S.-based supervisors and group participants who are themselves supervision scholars in China, describing their experiences and insights about the rewards and challenges of this telesupervision-of-supervision project.

Geographical pattern of methanogenesis in paddy and wetland soils across eastern China

Large variation of CH4 emissions from paddy and wetland ecosystems exists across different geographical locations in China. To obtain mechanistic understanding of this variation, we investigated the dynamics of methanogenesis over the course of glucose degradation in fourteen paddy field soils and five wetland soils collected from different regions of China. The results revealed that the maximal rate (2–3 mM per day) and the total amount (25–30 mM) of CH4 produced were similar across soil samples. The lag phase of methanogenesis, however, differed substantially with the shortest lag phase of 4 days in a paddy soil from north China and the longest of 32 days in a soil from south China, and this difference reflected a general geographical trend among all soils tested. Nitrate was reduced completely within 4 days in all soils. The reduction of Fe(III) and sulfate was completed after 21 days and 29 days, respectively. The depletion time of Fe(III) and sulfate were positively correlated with the lag phase of methanogenesis. Competition for common substrates between methanogens and iron and sulfate reducers, however, does not explain this coincidence because a slow production of CH4 was detected at the very beginning. It appears that the geographical variations in methanogenesis and the reduction of ferric iron and sulfate are related to the variation in soil pH but not to temperature, soil organic C and nutrient conditions in paddy and wetland soils across eastern China.

A effective DNA vaccine against diverse genotype J infectious hematopoietic necrosis virus strains prevalent in China

Infectious hematopoietic necrosis virus (IHNV) is the most important pathogen threatening the aquaculture of salmonid fish in China. In this study, a DNA vaccine, designated pIHNch-G, was constructed with the glycoprotein (G) gene of a Chinese IHNV isolate SD-12 (also called Sn1203) of genotype J. The minimal dose of vaccine required, the expression of the Mx-1 gene in the muscle (vaccine delivery site) and anterior kidney, and the titers of the neutralizing antibodies produced were used to evaluate the vaccine efficacy. To assess the potential utility of the vaccine in controlling IHNV throughout China, the cross protective efficacy of the vaccine was determined by challenging fish with a broad range of IHNV strains from different geographic locations in China. A single 100ng dose of the vaccine conferred almost full protection to rainbow trout fry (3g) against waterborne or intraperitoneal injection challenge with IHNV strain SD-12 as early as 4days post-vaccination (d.p.v.), and significant protection was still observed at 180d.p.v. Intragenogroup challenges showed that the DNA vaccine provided similar protection to the fish against all the Chinese IHNV isolates tested, suggesting that the vaccine can be widely used in China. Mx-1 gene expression was significantly upregulated in the muscle tissue (vaccine delivery site) and anterior kidney in the vaccinated rainbow trout at both 4 and 7d.p.v. Similar levels of neutralizing antibodies were determined with each of the Chinese IHNV strains at 60 and 180d.p.v. This DNA vaccine should play an important role in the control of IHN in China.

Genetic diversity and parentage assignment in Dojo loach, Misgurnus anguillicaudatus based on microsatellite markers

In this study, genetic diversity and structure of three Misgurnus anguillicaudatus populations from three different geographical locations in China (Hunan, Hubei and Henan province) were investigated using microsatellite markers. High level of genetic diversity of all three populations was revealed by expected heterozygosity (He), observed heterozygosity (Ho) and allele number. Significant genetic differentiations were found between all pairs of populations. The efficiency of eight microsatellite markers in parentage assignment of 540 progeny from twenty full-sib families was evaluated. Simulation based on allele frequency data demonstrated that probabilities of exclusion per locus range from 0.313 to 0.825 when no parent information is available and 0.504 to 0.904 when one parent is known. The assignment success rate based on the real data using eight markers was 96.85%. This study indicates that these M. anguillicaudatus resources are valuable genetic and breeding material for aquaculture and the microsatellite markers will be useful for investigation of genetic background and molecular marker-assisted selective breeding in this species.

Biological characteristics of Chinese precocious strain of eimeria acervulina and its immune efficacy against different field strains.

In this study, the biologic characteristics of one experimental precocious strain of Eimeria acervulina and seven field isolates from different geographic locations in China were compared, and the immune efficacy of two precocious strains against coccidiosis in chickens was assessed to explore their potential use as coccidiosis vaccines. All the different strains were purified by single oocyst separation and their monospecificity was confirmed using E acervulina-specific PCR assays. The average sizes of E. acervulina oocysts were 18.28-20.19 X 14.09-14.79 microm and the shape indexes were from 1.28 to 1.40. The prepatent periods ranged from 93 to 115 hr, except for the Heyuan precocious strain (HYP; 75 hr). Chickens infected with Huadu field strain (GHD) produced the highest oocyst output whereas HYP induced the lowest level. When inoculated with 50,000 sporulated oocysts or more, the average weight gains of infected chickens were reduced, with apparent clinical symptoms. To assess the immunogenicity of precocious strains HYP and Baoding (BDP), birds were orally immunized and challenged with seven different field strains of E. acervulina. Body weight gain, fecal oocyst output, and gut lesion scores were compared to evaluate their vaccine potential. The results showed that the average body weight gains of chickens in all the vaccinated and challenged groups were higher than those of nonvaccinated and challenged groups. In general, oocyst shedding was reduced 34.39%-95.31% and gut lesion scores decreased 31.03%-86.21% compared with unvaccinated and challenged control chickens. In summary, this study indicated that the precocious strains of E. acervulina could induce a protective immune effect with various responses against coccidiosis caused by different field strains.

A novel monopartite dsRNA virus isolated from the phytopathogenic fungus Ustilaginoidea virens and ancestrally related to a mitochondria-associated dsRNA in the green alga Bryopsis

In this study, we describe a novel mycovirus isolated from Ustilaginoidea virens, which was designated Ustilaginoidea virens nonsegmented virus 1 (UvNV-1). The sequence analysis revealed that UvNV-1 has two open reading frames (ORFs). ORF1 encodes an unknown protein, which is similar to the hypothetical protein BN7_5177 of Wickerhamomyces ciferrii. ORF2 encodes a putative RNA-dependent RNA polymerase (RdRp), which is most closely related to Bryopsis mitochondria-associated dsRNA (BDRM) and is likely expressed by a +1 ribosomal frameshift within the sequence CCC_UUU_CGA. The phylogenetic analysis of the RdRp of UvNV-1 showed that UvNV-1 represents a new virus taxon of mycoviruses with a partitivirus-like lineage that is classified into the family of picorna-like viruses. Based on northern hybridization, UvNV-1 was found to be common to U. virens from different geographic locations in China. The biological comparison of virus-free and infected fungal strains revealed that UvNV-1 is likely to be cryptic to its host.