通讯机构：
[Zhonghua Liu; Keqin Wang] K;Key Laboratory of Tea Science of Ministry of Education, Hunan Agricultural University, Changsha, China<&wdkj&>National Research Center of Engineering and Technology for Utilization of Botanical Functional Ingredients, Changsha, China<&wdkj&>Co-Innovation Center of Education Ministry for Utilization of Botanical Functional Ingredients, Changsha, China<&wdkj&>Key Laboratory of Tea Science of Ministry of Education, Hunan Agricultural University, Changsha, China<&wdkj&>Hunan Institute of Nuclear Agricultural Science and Space Breeding, Hunan Academy of Agricultural Sciences, Changsha, China
摘要：
This study evaluated the effects of fermentation time and temperature on the content of high molecular weight polyphenol mitochondrial activation factors (MAFs) and other polyphenols in Congou black tea using high-performance liquid chromatography (HPLC). There were two broad chromatographic peaks in the HPLC spectra of MAFs: MAFs-1 (16.163 min) and MAFs-2 (34.31 min); MAFs-2 was satisfactorily analyzed by HPLC, with separation by paper chromatography. The MAFs-2 contents increased gradually in different varieties of Congou black tea as the fermentation time and temperature increased; the maximum MAFs-2 content was 5.11% in Xiaoxianghong 21-3 after 8 hr of fermentation. The total polyphenols and catechins contents decreased, whereas the theabrownins contents increased as the fermentation time and temperature increased; the theaflavins and thearubigins contents in different Congou black teas showed different variation tendencies. Therefore, studies regarding changes in polyphenols during fermentation will help improve the quality of Congou black tea and enhance its health benefits. Novelty impact statement A new method for the determination of MAFs-2 by high-performance liquid chromatography combined with paper chromatography was established. The content of MAFs-2 increased initially and then stabilized as fermentation was continued from 2 to 8 hr, it increased gradually as the fermentation temperature was increased from 23 to 37 degrees C. These results provide a new analytical method for MAFs in black tea and a theoretical basis and technical guidance for improving the quality of Congou black tea.
通讯机构：
[Xiao, S.] I;[Kang, Z.] S;Institute of Biosciences and Biotechnology Research, United States;State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant Protection, China
关键词：
Arabidopsis thaliana;endoplasmic reticulum;extrahaustorial membrane;haustorium;powdery mildew;sugar transport protein
摘要：
Heavy metal passivators could reduce the transfer of heavy metal ions from soil to crops and exhibit great potential in safe cropping in heavy metal contaminated agricultural soils. However, the effects of heavy metal passivators on microbial diversity and microorganisms-based biogeochemical processes in agricultural soil are poorly explored. In this study, the effects of three heavy metal passivators, viz. lime, silicon (Si) fertilizer, and gypsum, on the structure and function of microorganisms in cadmium (Cd) contaminated paddy soils were investigated through activity of soil enzyme, microbial abundance and community structure by an in situ paddy field plot experiment. Our results showed that lime application changed the activity of phosphatase and urease through increasing bio-available phosphorus (AP) content in soil and soil pH, respectively. Lime application increased abundance and richness of the prokaryotic microbes in paddy soil, while gypsum application increased evenness of the eukaryotic microbes. Si fertilizer application resulted in the increase of evenness of both prokaryotic and eukaryotic microbes. The results presented in this study suggest that application of heavy metal passivator lime, Si fertilizer, and gypsum could improve microbial diversity and function in Cd contaminated paddy soil.
关键词：
Danish lakes;Nutrients;Compensatory dynamics;Portfolio effect;Selection effect;Top-down control
摘要：
Human-induced changes in external nutrient loading affect the phytoplankton community and abundance directly by changing the amount of nutrients available, but also indirectly through changes in the zooplankton (that is, grazer) community structure, mediated in part by changes in the fish community structure and biomass. Such shifts affect the species dynamics and community succession of lake phytoplankton communities, and they may ultimately influence community stability. However, the relative importance of different biotic mechanisms influencing the community stability of phytoplankton along nutrient and associated zooplankton grazing pressure gradients remains unclear. Here, we evaluated the importance of four potential stabilizing biotic metrics—taxon richness, synchrony, community dominance and biomass of phytoplankton to the seasonal stability over two decades of re-oligotrophication in 20 Danish lakes. We found no clear temporal patterns in seasonal stability across lakes but considerable variations in the individual lakes. Total phosphorus (TP) affected the seasonal stability of the phytoplankton communities either directly or indirectly through changes in community dominance. Total nitrogen (TN) influenced the seasonal stability indirectly via changes in phytoplankton taxon richness, synchrony, and community dominance. Grazer richness (that is, zooplankton taxa richness) impacted the seasonal stability indirectly through changes in phytoplankton taxon richness and synchrony. Grazing pressure, using the biomass ratio of zooplankton:phytoplankton as a proxy, had an indirect effect on seasonal stability via changes in synchrony and community dominance. Compensatory dynamics (as indicated by the synchrony of phytoplankton) exerted dominant control of phytoplankton seasonal stability at high TN and high grazer richness and pressure, while the portfolio effect (as indicated by taxon richness) contributed to phytoplankton seasonal stability at low TN and high grazer richness. However, a strongly negative selection effect (as indicated by community dominance of phytoplankton) was observed at high nutrient levels and low grazer richness. Grazer richness and grazing pressure had stronger stabilizing effects on the seasonal succession of the phytoplankton communities than did TP and TN. Our results highlight how various biotic mechanisms (for example, compensatory dynamics and portfolio effect) can change in their importance in maintaining the seasonal stability of phytoplankton communities subjected to nutrient and grazer control.
摘要：
In this study, a Ti3C2Tx MXene/coumarin (MC) composite has been designed and fabricated by the electrostatic self-assembly of the photoreversible coumarin-surfactant and Ti3C2Tx MXene, which exhibits an effective photoreversible performance. The structure of the MC composite transforms between the pleated and 3D undulating structures on irradiation with the 365/254 nm light for many cycles, thus, resulting in the conversion of the wettability between hydrophobic (123.1 degrees +/- 0.9 degrees) to almost superhydrophobic (149.5 degrees +/- 0.8 degrees) along with the Wenzel-mixed wetting regime reversible transition. Further, the gravimetric capacitance changes between 81 and 143F g(-1). This study not only demonstrates the design and preparation of an effective photoreversible and hydrophobic MC composite, but also provides a new approach to overcome the application limitations in the humid environment owing to the hydrophilic Ti3C2Tx MXene. As a result, the developed composite material exhibits a high potential of application in the photoreversible energy conversion devices. (C) 2021 Elsevier B.V. All rights reserved.
通讯机构：
[Feng-Chao Jiao] C;College of Animal Science and Veterinary Medicine, Xinyang Agriculture and Forestry University, Xinyang 464000, Henan province, China
摘要：
Haemaphysalis flava is the vector of several pathogens and has medical and veterinary importance. Transcriptome information of the ovary of H. flava is unavailable and limits understanding of its molecular basis of reproduction. We studied the ovary transcriptome of partially engorged and fully engorged H. flava using high-throughput RNA sequencing technology. A total of 53,025,360 and 57,942,890 clean reads were obtained with 7.95 GB and 8.69 GB clean bases in partially engorged ticks (PETs) and fully engorged ticks (FETs), respectively. The clean reads were assembled into 138,711 unigenes. A total of 72,043 unigenes (51.93%) were annotated and 66,668 unigenes (48.07%) were unknown. A total of 38,487 differentially expressed genes (DEGs) were found between PET and FET with 19,031 upregulated genes and 19,456 downregulated genes. The RNA-seq results were validated by qRT-PCR, including six upregulated genes and three downregulated genes. Some unigenes coding for nutrient transporters, proteases, and protease inhibitors were found and analyzed. This study was the first time to perform the transcriptome sequences of the ovary of partially engorged and fully engorged H. flava. The results can benefit the understanding of the molecular basis of ovary maturation and oogenesis of the H. flava and boost the development of the strategies for control of H. flava.
关键词：
Cd, Pb, Hg, Cr, Zn, Cu, Ni, Mn, As, Co;Environmental regulation;Fertilizer and pesticide use;Global pollution;Heavy metal pollution;Lakes;Mining and manufacturing;Pollution source;Pollution trend;Pollution-control measures;Rivers;Rock weathering;Sediment;Waste discharge
摘要：
Heavy metal pollution is a global problem although its sources and trends differ by region and time. To data, no published research has reported heavy metal pollution in global rivers and lakes. This study reviewed past sampling data across six continents from 1970 to 2018 and analyzed the trends and sources of 10 heavy metal species in sediments from 289 rivers and 133 lakes. Collectively, river sediments showed increasing trends in Cd, Cr, Ni, Mn, and Co and decreasing trends in Hg, indicating that rivers acted as a sink for the former and a source for the latter. Lake sediments showed increasing trends in Pb, Hg, Cr, and Mn, and decreasing trends in Cd, Zn, and As, indicating that lakes acted as a sink for the former and a source for the latter. Due to difference in natural backgrounds and development stage in continents, mean metal concentrations were generally higher in Europe and North America than in Africa, Asia, and South America. Principal component analysis showed that main metal source was mining and manufacturing from the 1970s to 1990s and domestic waste discharge from the 2000s to 2010s. Metal sources in sediments differed greatly by continent, with rock weathering dominant in Africa, mining and manufacturing dominant in North America, and domestic waste discharge dominant in Asia and Europe. Global trends in sediment metal loads and pollution-control measures suggest that the implementation of rigorous standards on metal emissions, limitations on metal concentrations in manufactured products, and the pretreatment of metal-contaminated waste have been effective at controlling heavy metal pollution in rivers and lakes. Thus, these efforts should be extended globally.
通讯机构：
[Dionysiou, Dionysios D] E;Environmental Engineering and Science Program, University of Cincinnati, OH 45221-0071, United States. Electronic address: dionysios.d.
摘要：
CoFe(2)O(4) (Cobalt ferrite, CF) nanoparticles were prepared, well characterized and applied as efficient solid catalyst in catalytic ozonation, named CF/O(3) process, for the removal of emerging organic contaminants (EOCs). The degradation and mineralization of clofibric acid (CA) in CF/O(3) process were dramatically enhanced in comparison with those under the O(3) system. Surface hydroxyl groups (HGs) were considered as an important factor for ozone decomposition and the reactive oxygen species (ROS) on the catalyst surface were mainly responsible for CA elimination. The contribution and formation of ROS, including hydroxyl radicals ((•)OH), especially superoxide radicals (O(2)(•-)), singlet oxygen ((1)O(2)), and hydrogen peroxide (H(2)O(2)) were evaluated, and a rational mechanism was elucidated accordingly. Probable degradation pathway of CA was proposed according to the organic intermediates identified. The acute toxicity of the treated solution increased during the first 15min and then declined rapidly and nearly disappeared as the reaction proceeded. In addition, acceptable catalytic performance of CF/O(3) can be obtained for the treatment of other EOCs and the treatment of natural surface water spiked with CA. This work presents an efficient and promising catalytic ozonation technique for the elimination of EOCs in complex water matrices.
作者：
Duan, D. -Y.;Chen, Z.;Fu, Y. -T.;Liu, G. -H.;Suleman;...
期刊：
Medical and Veterinary Entomology,2021年35(3):513-522 ISSN：0269-283X
通讯作者：
Suleman<&wdkj&>T.-Y. Cheng
作者机构：
[Fu, Y. -T.; Duan, D. -Y.; Liu, G. -H.; Chen, Z.; Cheng, T. -Y.] Hunan Agr Univ, Coll Vet Med, Hunan Prov Key Lab Prot Engn Anim Vaccines, Changsha, Hunan, Peoples R China.;[Duan, D. -Y.; Liu, G. -H.; Cheng, T. -Y.] Hunan Agr Univ, Coll Vet Med, Hunan Coinnovat Ctr Anim Prod Safety, Changsha, Hunan, Peoples R China.;[Suleman] Univ Swabi, Dept Zool, Swabi 23340, Khyber Pakhtunk, Pakistan.
通讯机构：
[Suleman] D;[T.-Y. Cheng] H;Hunan Provincial Key Laboratory of Protein Engineering in Animal Vaccines, College of Veterinary Medicine, Hunan Agricultural University, Changsha, Hunan Province, China<&wdkj&>Hunan Co-Innovation Center of Animal Production Safety, College of Veterinary Medicine, Hunan Agricultural University, Changsha, Hunan Province, China<&wdkj&>Department of Zoology, University of Swabi, Swabi, 23340 Khyber Pakhtunkhwa, Pakistan
摘要：
In this study, the authors sequenced and characterized the complete mitochondrial (mt) genomes of two hard ticks of the genus Ixodes, I. nipponensis and Ixodes (Pholeoixodes) sp., which were 14 505 and 14 543 bp in length, respectively. Their mt genomes encoded 37 genes, including 13 protein-coding genes (PCGs), 22 transfer RNA genes and two ribosomal RNA genes, and have only one non-coding region. The gene order in their mt genomes was the same as that of other Ixodes spp. mt genomes. The average sequence identity, combined nucleotide diversity, non-synonymous/synonymous substitutions ratio analyses consistently demonstrated that cox1, rrnS, cox2, cox3 and cytb were the most conserved and atp8, nad6 and nad2 were the most variable genes across Ixodes mitogenomes. Phylogeny of the present Ixodes spp., and other selected hard tick species, based on concatenated amino acid sequences of PCGs, confirmed their position within the genus Ixodes and sub-family Ixodinae. The novel mt markers described herein will be useful for further studies of the population genetics, molecular epidemiology and systematics of hard ticks.
通讯机构：
[ Suleman] D;[Yu Zhao] H;Department of Zoology, University of Swabi, Swabi 23340, Khyber Pakhtunkhwa, Pakistan<&wdkj&>Hunan Provincial Key Laboratory of Protein Engineering in Animal Vaccines, College of Veterinary Medicine, Hunan Agricultural University, Changsha, Hunan province 410128, China<&wdkj&>College of Animal Science and Veterinary Medicine, Xinyang Agriculture and Forestry University, Xinyang, Henan province 464000, PR China
关键词：
Genetic distance;Phylogenetic analyses
摘要：
The family Tabanidae (Insecta: Diptera) is one of the economically most important group of haematophagous insects, causing millions of livestock deaths per year. However, current knowledge on the mitochondrial genomes (mitogenomes) from this family is limited. Additional tabanid mitogenomes characterization is of utmost importance for their identification, epidemiologic and phylogenetic studies. We sequenced the mt genomes of six horseflies with an Illumina platform and their phylogenetic relationship was conducted with other infraorder Tabanomorpha members with available mt genome datasets. All six newly sequenced mitogenomes were typical 37-gene circular structures retaining the gene order of Tabanomorpha. The trnQ, trnM and trnA were highly conserved among the six mitogenomes (identity = 100%). The TΨC arm and variable loop regions were relatively more variable compared to the amino acid receptor arm, anticodon arm and DHU arm of the tRNAs. Among 13 protein-coding genes (PCGs) of tabanids mitogenomes, the highest nucleotide diversity was detected in atp8, cox1, cox3, nad6 and cytb (0.1 for each). In addition, atp8 genes exhibited the highest evolutionary rate (ω = 0.24) among 13 PCGs. The interspecies K2P genetic distances among some Tabanus spp. across the mitogenome was greater (0.08) than intergeneric genetic distance between T. amaenus and Atylotus miser (0.07). Phylogenetic analyses revealed non-monophyletic relationships among horseflies of the genus Tabanus. The present study showed mt gene order is highly conserved within Tabanus species. Our mito-phylogenomic analysis supports the paraphyly of the genus Tabanus. The new data provide novel genetic markers for studies of population genetics and systematics of horseflies.
作者机构：
[Pan, Runhui; Fan, Yulei; Sun, Youcai; Zhu, Yusong; Wu, Yuping; Wang, Jing; Fu, Lijun; Ou, Man] Nanjing Tech Univ, Sch Energy Sci & Engn, Coll Chem Engn, Nanjing 211816, Jiangsu, Peoples R China.;[Shi, Feifei; Lai, Jianwei] Penn State Univ, John & Willie Leone Family Dept Energy & Mineral, University Pk, PA 16802 USA.;[Wu, Xiongwei] Hunan Agr Univ, Sch Chem & Mat Sci, Changsha 410128, Peoples R China.
通讯机构：
[Wu, Yuping] N;[Shi, Feifei] P;Nanjing Tech Univ, Sch Energy Sci & Engn, Coll Chem Engn, Nanjing 211816, Jiangsu, Peoples R China.;Penn State Univ, John & Willie Leone Family Dept Energy & Mineral, University Pk, PA 16802 USA.
摘要：
Photocatalysts with a direct Z-scheme heterojunction are promising by virtue of the effectively enhanced separation of charge carriers, high retention of redox ability and the absence of backward photocatalytic reactions. Their activity depends on band alignment and interfacial configurations between two semiconductors for charge carrier kinetics and the effective active sites for photochemical reactions. Herein, a two-dimensional (2D) graphitic carbon nitride/N-doped carbon (C3N4/NC) photocatalyst is synthesized by a gas template (NH4Cl)-assisted thermal condensation method. C3N4/NC has the synthetic merits of a direct Z-scheme heterojunction, 2D-2D interfacial contact, and enhanced specific surface area to improve charge separation kinetics and provide abundant active sites for photochemical reaction. It exhibits an over 46-fold increase of the photocatalytic hydrogen production rate compared to bulk C3N4 under visible light illumination. This work demonstrates the great potential of 2D Z-scheme heterojunctions for photocatalysis and will inspire more related work in the future.
作者机构：
[Chen, Mo-Xian; Song, Tao; Zhu, Fu-Yuan] Nanjing Forestry Univ, Coll Biol & Environm, Coinnovat Ctr Sustainable Forestry Southern China, Nanjing 210037, Peoples R China.;[Yang, F; Zhang, Jian-Hua; Song, Tao; Das, Debatosh; Yang, Feng] Chinese Univ Hong Kong, Shenzhen Res Inst, Shenzhen 518057, Peoples R China.;[Ye, Neng-Hui] Hunan Agr Univ, Coll Agr, Southern Reg Collaborat Innovat Ctr Grain & Oil C, Changsha 410128, Peoples R China.;[Zhang, Jian-Hua; Wang, Guan-Qun] Hong Kong Baptist Univ, Dept Biol, Kowloon, Hong Kong, Peoples R China.;[Chen, Mo-Xian] Chinese Acad Sci, Shenzhen Inst Adv Technol, Shenzhen Inst Synthet Biol, CAS Key Lab Quantitat Engn Biol, Shenzhen 518055, Peoples R China.
通讯机构：
[Yang, F; Zhang, JH; Zhang, Jian-Hua] C;[Zhang, Jian-Hua] H;Chinese Univ Hong Kong, Shenzhen Res Inst, Shenzhen 518057, Peoples R China.;Hong Kong Baptist Univ, Dept Biol, Kowloon, Hong Kong, Peoples R China.;Chinese Univ Hong Kong, Sch Life Sci, Shatin, Hong Kong, Peoples R China.
摘要：
Bovine mammary epithelial cells undergo an increase in metabolic rate, mitochondrial dysfunction, and oxidative stress after calving. Nuclear factor erythroid 2-related factor 2 (NFE2L2), a master regulator of cellular redox homeostasis, plays crucial roles in the regulation of mitochondrial function. The objective of this study was to investigate the role of NFE2L2 on mitochondrial function in bovine mammary epithelial cells under hyperlipidemic conditions. Three experiments were conducted as follows: (1) the immortalized bovine mammary epithelial cell line MAC-T was treated with various concentrations of free fatty acids (FFA; 0, 0.6, 1.2, or 2.4 mM) for 24 h to induce stress; (2) MAC-T cells were transfected with small interfering RNA targeting NFE2L2 (si-NFE2L2) and scrambled nontarget negative control (si-Control) for 48 h; and (3) MAC-T cells were pretreated with 10 mu M sulforaphane (SFN), an activator of NFE2L2, for 24 h followed by treatment with 1.2 mM FFA for an additional 24 h. Results indicated that exogenous FFA challenge induced linear and quadratic increases in concentrations of mitochondrial reactive oxygen species (ROS). Compared with 0 mM FFA, mitochondrial membrane potential, mRNA abundance of oxidative phosphorylation complexes (CO I-V), protein abundance of nuclear respiratory factor 1 (NRF1), peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1 alpha), mitochondrial transcription factor A (TFAM), and NFE2L2 along with the contents of ATP, mitochondrial DNA (mtDNA), and total mitochondria were greater in the MAC-T challenged with 0.6 mM FFA group, but lower in the 1.2 and 2.4 mM FFA cultures. Knockdown of NFE2L2 via small interfering RNA led to greater mitochondrial ROS content and lower mitochondrial membrane potential along with contents of ATP, mtDNA, and total mitochondria. The SFN pretreatment upregulated protein abundance of NFE2L2 and attenuated the downregulation of NFE2L2 induced by FFA. Pretreatment with SFN attenuated the downregulation induced by FFA of PGC1 alpha, NRF1, and TFAM protein abundance along with contents of mtDNA and total mitochondria. Furthermore, SFN pretreatment attenuated the upregulation of mitochondrial ROS content, the downregulation of mitochondrial membrane potential, and the decreases in ATP, mtDNA, and mitochondrial content induced by FFA. Overall, data indicated that FFA inhibit NFE2L2, resulting in mitochondrial dysfunction and ROS production in bovine mammary epithelial cells. Thus, NFE2L2 may be a promising therapeutic target against metabolic challenge-driven mitochondrial dysfunction and oxidative stress in bovine mammary epithelial cells.
