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Iron-sulfur (Fe-S) cluster assembly genes play important roles in plant growth and development. However, their biological function in fruit crops is still unknown, especially in strawberry. In this study, Fe depletion significantly inhibited the growth, photosynthesis, Fe accumulation level and the enzyme activity of Fe-S proteins of aconitase (ACO), nitrate reductase (NiR) and succinate dehydrogenase (SDH) in strawberry seedlings. In addition, 40 Fe-S cluster assembly genes were isolated from strawberry, which were significantly varied among different tissues/organs and were differentially responded to Fe depletion in different tissue parts. In total, 79% of the responsive genes were up-regulated in shoots, while 65% of the responsive genes were down-regulated in roots under Fe depletion. Moreover, the expression level of ISU1 was the highest in strawberry tissues, especially in young fruits, and over-expression of ISU1 gene in Arabidopsis significantly enhanced the Fe accumulation, leaf total chlorophyll, ACO and SDH activities in transgenic lines, and strengthened plant tolerance to Fe depletion. This study provides gene resources to elucidate the molecular mechanisms of Fe-S cluster assembly in strawberry, and lays a theoretical foundation to reveal Fe nutrition and metabolism in Rosaceae fruits. • Fe depletion inhibited the growth, photosynthesis, Fe content and activity of ACO, NiR and SDH in strawberry seedlings. • Forty Fe–S cluster assembly genes were isolated and identified in strawberry, which were differentially responded to Fe depletion. • Non-functional scaffolds are more likely to be lost in perennial plants, including strawberry. • Expression level of ISU1 was the highest in strawberry, and overexpression of ISU1 in Arabidopsis enhanced plant tolerance to Fe deficiency. [ABSTRACT FROM AUTHOR]

The study investigated the adsorption of dissolved organic carbon (DOC) on Chinese soils from four long-term experiments involving five treatments: (1) no fertilization (control), (2–4) inorganic nitrogen (N), phosphorus (P), and potassium (K) fertilization (N, NP, and NPK), (5) NPK plus manure (NPKM). The results showed that DOC adsorption followed a modified Langmuir isotherm model effectively (R2 = 0.912 ~ 0.991). The maximum adsorption capacity (Qmax) (i.e. saturation deficits) generally increased with increasing soil organic carbon (SOC) due to fertilization in Luvic Phaeozem, Haplic Gypsisols, and Eutric Cambisols. However, it decreased significantly in acidic soils (Haplic Acrisols) from 15.59 g/kg for control, to 13.96, 13.03, 9.30 and 8.02 g/kg for N, NP, NPK and NPKM, respectively. Moreover, long-term fertilization, particularly with organic fertilization (e.g. NPKM), resulted in an increase of carbon (C) saturation by 1.42 g/kg (5.52%) in Luvic Phaeozem, 9.27 g/kg (44.29%) in Haplic Gypsisols, and 3.75 g/kg (27.66%) in Eutric Cambisols; however, there was a slight decrease by 1.70 g/kg (−7.49%) in Haplic Acrisols. Canonical correlation analysis (CCA) revealed that clay content and soil available iron (AFe) might be the crucial factors controlling C deficits, and subsequently, C saturation, along with current SOC. In conclusion, long-term fertilization contributed to C saturation in neutral-to-alkaline soils, but not in acidic soils. Thus, further attention should be paid to the long-term effects of fertilization on C saturation. [ABSTRACT FROM AUTHOR]

Iron (Fe) is required for the iron–sulphur (Fe–S) cluster biosynthesis, which occurs in chloroplasts, mitochondria and cytosol that needs dozens of genes. However, molecular mechanisms of Fe metabolism in fruit trees are largely rare, especially towards fruit development and ripening. In this work, we characterized ‘Xiahui8′ peach development, and analyzed expression profiles of 44 Fe–S cluster biosynthesis genes during different fruit development stages. The development of ‘Xiahui8′ peaches last for an average period of 130 days, followed by a rapid on-tree ripening during 7 days. Notably, the Fe accumulation in peach flesh was negatively correlated to fruit weight and volume, but positively correlated to flesh firmness. Quantitative Real-Time PCR (qRT-PCR) analysis showed that Fe–S cluster biosynthesis genes were differentially expressed during distinct fruit development stages. A majority of plastid SUF and mitochondrial ISC machinery genes were gradually enhanced along with fruit growth, and began to decrease since commercial harvest phase. The highest expression level of all cytosolic CIA machinery genes were appeared in early fruitlet formation stage, and gradually reduced until fruit ripening. Moreover, foliar spraying of amino acid-Fe compound fertilizer significantly enhanced the total soluble solid (TSS) content in peaches, accompanied by strengthened flesh firmness, Fe concentration, and succinate dehydrogenase (SDH) and aconitase (ACO) activities. Thirteen Fe–S cluster biosynthesis genes were responsive to fertilizer treatment, whose expression level were significantly induced, with the exception of HSCA2 that was reduced. Our findings provided molecular basis for Fe metabolism in peach fruit development, and revealed potential genes for further functional verification. [ABSTRACT FROM AUTHOR]

Focuses on a study of carbon thin films using Fourier-transformation infrared spectroscopy. Effect of the intermolecular interactions between carbon molecules in the films; Observations about vibrational modes; Discussion on the mechanism of changes of vibrational modes.

* Premise of the study: The potassium cation (K+), one of the most abundant cations in cells, improves plant tolerance to various abiotic stresses. Alligatorweed (Alternanthera philoxeroides) is well known for its strong capacity to accumulate K+. The distinctive K+ accumulation capability of alligatorweed is linked to a high-affinity K+ transport facilitated by K+-uptake transporters (ApKUPs). * Methods: A putative K+ transporter gene, ApKUP4, was isolated from alligatorweed using degenerate primers and rapid amplification of cDNA ends (RACE) techniques. Gene expression profiles were performed by quantitative real time PCR and northern blot analysis. Moreover, we introduced ApKUP4 into Arabidopsis to determine its function in improving crop nutrition and NaCl stress tolerance. * Key results: ApKUP4 was localized throughout the entire alligatorweed plant, and its expression was stimulated in the stems and roots under K+ deficiency, osmotic stress, and salinity stress. Northern blot analysis revealed that ApKUP4 was present in all tested organs of transgenic Arabidopsis plants. Compared with the wild type, Arabidopsis plants overexpressing ApKUP4 showed improved growth and K+ homeostasis. Moreover, ApKUP4 overexpression in Arabidopsis plants enhanced plant tolerance to salinity stress, as evidenced by reduced water loss and ROS generation, associated with enhanced photosynthesis, nutritional status, and enzymatic antioxidants. * Conclusions: The present study provides direct evidence that the alligatorweed K+ transporter gene, ApKUP4, contributes to salinity tolerance in transgenic Arabidopsis seedlings, demonstrating the essentiality of potassium homeostasis for plant salinity tolerance. [ABSTRACT FROM AUTHOR]

Soil acidification has occurred and accelerated in Jiaodong Peninsula, China, causing serious problems, such as manganese (Mn) toxicity and soil organic carbon (SOC) losses. However, the relationships between SOC and soil Mn are still unclear. This study aimed to explore the changes of Mn fractions and SOC under soaking conditions and the acidification‐induced positive coupled relationship between them. A sequential extraction for Mn species after acid soaking of a Cambisol was conducted, and the soil (pre‐ and post‐soaking) was characterised by X‐ray diffraction (XRD) and scanning electron microscope (SEM). The results showed that acidification of a Cambisol (from pH 6.48 to pH 2.79) induced SOC losses (15.8% of initial SOC). Meanwhile, lower mobile or immobile Mn (especially oxide‐Mn) significantly decreased, accompanied by an increase in readily soluble Mn. It was further shown that the amount of decrease in free Mn reached 268.7 mg kg−1, accounting for 93.8% of the total loss of soil Mn, indicating that the reductive dissolution of amorphous Mn (III/IV) oxides is the dominant reaction in acidified Cambisols. This result was also supported by XRD and SEM. Correlation analysis showed that under soil acidification, the reductive dissolution of amorphous Mn (III/IV) oxides drove losses of both SOC and soil Mn. Therefore, a possible reaction mechanism was proposed: at neutral and alkaline pH, immobile complexes of Mn (III/IV) and particulate organic carbon (POC) formed; and, at acidic pH, readily mobile complexes of Mn (II) and dissolved organic carbon (DOC) formed. Our research suggested that Mn‐organic carbon complexes regulated the transport, transformation, and leaching of soil Mn and SOC, and future research should focus on the soil acidification‐driven Mn reduction‐carbon oxidation processes. Highlights: Acidification accelerated soil organic carbon losses.Acidification induced reductive dissolution of amorphous Mn (III/IV) oxides.A positive couple relationship between SOC and soil Mn existed in acidified soils. [ABSTRACT FROM AUTHOR]

Mycoviruses are usually transmitted horizontally via hyphal anastomosis and vertically through sporulation in natural settings. Oyster mushroom spherical virus (OMSV) is a mycovirus that infects Pleurotus ostreatus, with horizontal transmission via hyphal anastomosis. However, whether OMSV can be vertically transmitted is unclear. This study aimed to investigate the transmission characteristics of OMSV to progeny via basidiospores and horizontally to a new host. A total of 37 single-basidiospore offspring were obtained from OMSV-infected P. ostreatus and Pleurotus pulmonarius for Western blot detection of OMSV. The OMSV-carrying rate among monokaryotic isolates was 19% in P. ostreatus and 44% in P. pulmonarius. Then, OMSV-free and OMSV-infected monokaryotic isolates were selected for hybridization with harvested dikaryotic progeny strains. Western blot analyses of the offspring revealed that the OMSV transmission efficiency was 50% in P. ostreatus and 75% in P. pulmonarius, indicating vertical transmission via sexual basidiospores. Furthermore, we observed the horizontal transfer of OMSV from P. pulmonarius to Pleurotus floridanus. OMSV infection in P. floridanus resulted in significant inhibition of mycelial growth and yield loss. This study was novel in reporting the vertical transmission of OMSV through basidiospores, and its infection and pathogenicity in a new host P. floridanus. [ABSTRACT FROM AUTHOR]

Climate change affects many aspects of the physiological and biochemical processes of growing maize and ultimately its yield. A comprehensive climate suitability model is proposed that quantifies the effects of temperature, precipitation, solar radiation, and wind in different phenological stages of maize. It is calibrated using weather and yield data from China's Henan Province. The comprehensive suitability model showed the capability of correctly hindcasting observed temporal and spatial changes in maize phenology in response to climatic factors. The predicted yield based on the suitability model can well match the recorded field yield very well from 1971–2020. The results of correlation showed that the yields are more closely related to multi-weather factors, temperature and precipitation than to solar radiation and wind. The sensitivity analysis illustrates that temperature and precipitation are the dominant weather factors affecting yield changes based on a direct differentiation method. The comprehensive suitability model can provide a scientific support and analysis tool for predicting grain production considering climate changes. [ABSTRACT FROM AUTHOR]

Brassinosteroid-insensitive-1 (BRI1) plays important roles in various signalling pathways controlling plant growth and development. However, the regulatory mechanism of BRI1 in brassinosteroid (BR)-mediated signalling for shoot growth and wood formation in woody plants is largely unknown. In this study, PtBRI1.2 , a brassinosteroid-insensitive-1 gene, was overexpressed in poplar. Shoot growth and wood formation of transgenic plants were examined and the regulatory genes involved were verified. PtBRI1.2 was localized to the plasma membrane, with a predominant expression in leaves. Ectopic expression of PtBRI1.2 in Arabidopsis bri1-201 and bri1-5 mutants rescued their retarded-growth phenotype. Overexpression of PtBRI1.2 in poplar promoted shoot growth and wood formation in transgenic plants. Further studies revealed that overexpression of PtBRI1.2 promoted the accumulation of PtBZR1 (BRASSINAZOLE RESISTANT1) in the nucleus, which subsequently activated PtWND s (WOOD-ASSOCIATED NAC DOMAIN transcription factors) to up-regulate expression of secondary cell wall biosynthesis genes involved in wood formation. Our results suggest that PtBRI1.2 plays a crucial role in regulating shoot growth and wood formation by activating BR signalling. [ABSTRACT FROM AUTHOR]

A compact microwave ion source has been developed. The magnetic field in the source is produced by a permanent magnet. The dimension of the source is 46 mm in diameter and 50 mm in height. The discharge chamber and extraction hole is 20 and 2 mm in diameter, respectively. The microwave frequency is 2.45 GHZ and the power consumption is less than 50 W. It is easy to extract a total beam current of more than 1 mA from this compact source. [ABSTRACT FROM AUTHOR]

A new PIG ion source has been developed with the cathodes made of single-crystal LaB[sub 6] and a permanent magnet. The experiment showed that the single-crystal LaB[sub 6] is better than the common multicrystal LaB[sub 6] in electron emissivity, ion bombardment resistance, and cathode lifetime. That ion source can produce a total beam current of about 1 mA at the low arc power of about 30 W. [ABSTRACT FROM AUTHOR]

Low‐temperature storage is a widely used method for peach fruit storage. However, the impact of PpCBFs on pectin degradation during low‐temperature storage is unclear. As such, in this study, we stored the melting‐flesh peach cultivar "Fuli" at low temperature (LT, 6°C) and room temperature (RT, 25°C) to determine the effect of different temperatures on its physiological and biochemical changes. Low‐temperature storage can inhibit the softening of "Fuli" peaches by maintaining the stability of the cell wall. It was found that the contents of water‐soluble pectin and ionic‐soluble pectin in peach fruit stored at RT were higher than those stored at LT. The enzyme activities of polygalacturonase (PG), pectate lyase (PL), and pectin methylesterase (PME) were all inhibited by LT. The expressions of PpPME3, PpPL2, and PpPG were closely related to fruit firmness, but PpCBF2 and PpCBF3 showed higher expression levels at LT than RT. The promoters of PpPL2 and PpPG contain the DER motif, which suggested that PpCBF2 and PpCBF3 might negatively regulate their expression by directly binding to their promoters. These results indicated that LT may maintain firmness by activating PpCBFs to repress pectin‐degradation‐related enzyme genes during storage. [ABSTRACT FROM AUTHOR]

Background: Following its resurgence in 1982, rodent plague has been linked to a wide range of circulation risks in Yunnan Province. The most serious public health concern associated with effective plague control is determining how various ecological variables influence the differential risk of transmission. Methods: We investigated the population dynamics of the hosts and vectors using large-scale epidemiological surveillance data. In a seasonal eco-epidemiological model, we evaluated the impact of ecological conditions on the vectored flea index (VFI) to determine the rate of plague transmission. Results: The findings revealed a changing species composition in natural foci over time. Additionally, shifting distributional ranges of species by elevation may be vital in modulating the VFI. The model estimates indicate that the dynamic VFI contributes to spatiotemporal variance in transmission. Conclusions: The VFI could be a critical ecological indicator, allowing for real-time tracking and prompt intervention in the circulation of rodent plague. Understanding eco-epidemiological diversity can provide essential insights into effective responses to future plague resurgence. Author summary: Plague have resurged among rodents in Yunnan Province since 1982, and intermittently occurs among humans. Yet the local risk of rodent plague dynamics has been highly diverse across ecological contexts. In natural foci, suggestions for this ecological diversity include high species richness and cyclic transmission between hosts and vectors. Here, we developed an eco-epidemiological framework to position the epidemiological dynamics of rodent plague in local ecological contexts. Our results suggest that diverse ecological conditions may have shaped the local risk of plague transmission in Yunnan Province. Typically, incremental of elevation has been associated with the tradeoff between the increased diversity and averted fraction of main host and vector species. More importantly, vectored flea index could be a critical ecological indicator for plague management. [ABSTRACT FROM AUTHOR]

SINA (Seven in absentia) proteins in the subtype of E3 ubiquitin ligase family play a crucial role in plant growth and development. However, their functions in response to salt and osmotic stresses in oil crops are still largely unknown. In this study, a total number of 23 BnaSINAs were identified in the rapeseed genome. Chromosome location and collinear relationship analyses revealed that they were unevenly distributed on 13 chromosomes, and have gone through 22 segmental duplication events under purifying selection. Phylogenetic and gene structural analyses indicated that they belonged to five main groups, and those in the same subgroup showed similar gene structure. All BnaSINAs were predicted to form homo- or heterodimers. Except BnaSINA7, BnaSINA11, BnaSINA17 and BnaSINA18, which lacked the N-terminal RING finger, all BnaSINAs contained a conserved C-terminal SINA domain, a typical structural feature of the RING-type E3 ligase family. Transcriptional expression analyses demonstrated that most BnaSINAs were ubiquitously expressed in roots, stems, leaves, flowers, pods and seeds, and all were responsive to salt and osmotic stresses. Further, yeast two-hybrid and Arabidopsis mutant complementation analyses demonstrated that BnaSINA4 interacted with BnaSINA17 to form heterodimer, and expression of BnaSINA17 in the Arabidopsissina2 mutant restored its growth resistance to salt and osmotic stresses. Our findings provide an important genetic foundation for the functional elucidation of BnaSINAs and a novel gene resource for the breeding of new oil crop cultivars with improved abiotic stress resistance. [ABSTRACT FROM AUTHOR]

A Freeman ion source for the LC-2F implanter was improved. In this source the filament is a 2-mm-diam tungsten wire covered with a LaB[sub 6] cylinder. The discharge chamber is made of antioxidation and high temperature resistant stainless steel. The source lifetime is more than 10 h in pure oxygen discharges, and no oxidation phenomenon occurs on the discharge chamber during long time operation. The source discharge and extraction characteristics are similar to those used before for BF[sub 3] and P discharge. So the source can be used in a wide range of microelectronics and material science. [ABSTRACT FROM AUTHOR]

Background: Plague, a Yersinia pestis infection, is a fatal disease with tremendous transmission capacity. However, the mechanism of how the pathogen stays in a reservoir, circulates and then re-emerges is an enigma. Methodology/Principal findings: We studied a plague outbreak caused by the construction of a large reservoir in southwest China followed 16-years’ surveillance. Conclusions/Significance: The results show the prevalence of plague within the natural plague focus is closely related to the stability of local ecology. Before and during the decade of construction the reservoir on the Nanpan River, no confirmed plague has ever emerged. With the impoundment of reservoir and destruction of drowned farmland and vegetation, the infected rodent population previously dispersed was concentrated together in a flood-free area and turned a rest focus alive. Human plague broke out after the enzootic plague via the flea bite. With the construction completed and ecology gradually of human residential environment, animal population and type of vegetation settling down to a new balance, the natural plague foci returned to a rest period. With the rodent density decreased as some of them died, the flea density increased as the rodents lived near or in local farm houses where had more domestic animals, and human has a more concentrated population. In contrast, in the Himalayan marmot foci of the Qinghai-Tibet Plateau in the Qilian Mountains. There are few human inhabitants and the local ecology is relatively stable; plague is prevalence, showing no rest period. Thus the plague can be significantly affected by ecological shifts. [ABSTRACT FROM AUTHOR]

Background: HIV drug resistance increased with the widespread use of antiretroviral drugs, and posed great threat to antiretroviral therapy (ART). Pu'er Prefecture, lying in the southwest of Yunnan Province, China, borders Myanmar, Laos and Vietnam, is also the area where AIDS was discovered earlier, however, in which there has been no information on HIV drug resistance.Methods: A cross-sectional survey of pretreatment drug resistance (PDR) was conducted in Pu'er Prefecture in 2021. Partial pol gene sequences were obtained to analyze drug resistance and construct genetic transmission network. HIV drug resistance was analyzed using the Stanford University HIVdb algorithm.Results: A total of 295 sequences were obtained, among which 11 HIV-1 strain types were detected and CRF08_BC (62.0%, 183/295) was the predominant one. Drug resistance mutations (DRMs) were detected in 42.4% (125/295) of the sequences. The prevalence of PDR to any antiretroviral drugs, nucleoside reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs) and protease inhibitors (PIs) were 10.8% (32/295), 9.5% (28/295), 1.0% (3/295) and 0.3% (1/295), respectively. The risk of PDR occurrence was higher among individuals with CRF01_AE strain types. HIV-1 molecular network was constructed, in which 56.0% (42/75) of links were transregional, and 54.7% (41/75) of links were associated with Lancang County. Among the sequences in the network, 36.8% (35/95) harbored DRMs, and 9.5% (9/95) were drug resistance strains. Furthermore, 8 clusters had shared DRM.Conclusion: The overall prevalence of PDR in this study was in a moderate level, but NNRTIs resistance was very approaching to the threshold of public response initiation. PDR was identified in the transmission network, and DRMs transmission was observed. These findings suggested that the consecutive PDR surveillance should be conducted in this region. [ABSTRACT FROM AUTHOR]

Halophyte Tamarix ramosissima. Lcdcb (T. ramosissima) are known as the representative of Tamarix plants that are widely planted in salinized soil. However, molecular mechanisms towards salt tolerance and adaptation are largely rare. In this study, we carried out RNA-sequence and transcriptome analysis of T. ramosissima in response to NaCl stress, screened differentially expressed genes (DEGs) and further verified by qRT-PCR. Results showed that 105702 unigenes were spliced from the raw data of transcriptome sequencing, where 54238 unigenes were retrieved from KEGG, KOG, NR, and SwissProt. After 48 hours of NaCl treatment, the expression levels of 6374 genes were increased, and 5380 genes were decreased in leaves. After 168 hours, the expression levels of 3837 genes were up-regulated and 7808 genes were down-regulated. In particular, 8 transcription factors annotated to the KEGG Pathway were obtained, involving the WRKY and bZIP transcription family. In addition, KEGG pathway annotation showed that expression of 39 genes involved in ROS scavenging mechanisms were significantly changed, in which 21 genes were up-regulated and 18 genes were down-regulated after 48 hours as well as 15 genes were up-regulated and 24 genes were down-regulated after 168h. Simultaneously, the enzyme activities of SOD and POD were significantly enhanced under NaCl treatment, but the enzyme activity of CAT was not significantly enhanced. Moreover, WRKY, MYB and bZIP may participate in the process of salt resistance in T. ramosissima. This study provides gene resources and a theoretical basis for further molecular mechanisms of salt tolerance in T. ramosissima. [ABSTRACT FROM AUTHOR]

Shaker-type K+ channels are critical for plant K+ acquisition and translocation that play key roles during plant growth and development. However, molecular mechanisms towards K+ channels are extremely rare in fruit trees, especially in peach. In this study, we identified 7 putative shaker-type K+ channel genes from peach, which were unevenly distributed on 5 chromosomes. The peach shaker K+ channel proteins were classified into 5 subfamilies, I-V, and were tightly clustered with pear homologs in the phylogenetic tree. Various cis-acting regulatory elements were detected in the promoter region of the shaker-type K+ channel genes, including phytohormone-responsive, abiotic stress-responsive, and development regulatory elements. The peach shaker K+ channel genes were expressed differentially in distinct tissues, and PpSPIK was specifically expressed in the full-bloom flowers; PpKAT1 and PpGORK were predominantly expressed in the leaves, while PpAKT1, PpKC1, and PpSKOR were majorly expressed in the roots. The peach shaker K+ channel genes were differentially regulated by abiotic stresses in that K+ deficiency, and ABA treatment mainly increased the shaker K+ channel gene expression throughout the whole seedling, whereas NaCl and PEG treatment reduced the shaker K+ channel gene expression, especially in the roots. Moreover, electrophysiological analysis demonstrated that PpSKOR is a typical voltage-dependent outwardly rectifying K+ channel in peach. This study lays a molecular basis for further functional studies of the shaker-type K+ channel genes in peach and provides a theoretical foundation for K+ nutrition and balance research in fruit trees. [ABSTRACT FROM AUTHOR]

Cytochrome P450 monooxygenases (CYP450s) play crucial roles in the regulation of plant growth and response to abiotic stress. However, their functions in woody trees are still largely unknown. Previously, we reported that expression of the rice cytochrome P450 monooxygenase gene OsCYP714D1 increased gibberellic acid (GA) accumulation and shoot growth in transgenic poplar. In this work, we demonstrate that expression of OsCYP714D1 improved the salt tolerance of transgenic poplar plants. Compared to wild type, plant height and K+ content were significantly higher, whereas plant growth inhibition and Na+ content were significantly lower, in transgenic plants grown under high salt stress condition. Transcriptomic analyses revealed that OsCYP714D1 expression up-regulated the expressions of GA biosynthesis, signaling and stress responsive genes in transgenic plants under both normal and high salt stress conditions. Further gene ontology (GO) analyses indicated that genes involved in plant hormone and ion metabolic activities were significantly enriched in transgenic plants. Our findings imply that OsCYP714D1 participated in the regulation of both shoot growth and salt resistance through regulating gibberellin and ion homeostasis in transgenic poplar, and it can be used as a candidate gene for the engineering of new tree varieties with improved biomass production and salt stress resistance. • Constitutive expression of OsCYP714D1 promoted growth and salt tolerance in transgenic poplar. • Expression of gibberellin synthesis and metabolism genes was affected in OsCYP714D1 transgenic poplar. • OsCYP714D1 transgenic poplar showed altered ion homeostasis and related gene expression. [ABSTRACT FROM AUTHOR]

A cold-cathode penning ion gauge (PIG) source built with permanent magnet for the production of intense O- ion beam has been developed for the simultaneous acceleration of O- and O+ ion beams in a 1 MV RFQ accelerator. O- ion beam of intensity of 1.5 mA has been produced with this small PIG ion source. The effects of the source magnetic field, cathode material and extraction aperture on the production of the intense O- ion beam have been investigated and will be presented in this article. [Copyright &y& Elsevier]

Alternative splicing (AS) plays a crucial role in plant growth, development and response to various environmental changes. However, whether alternative splicing of MADS-box transcription factors contributes to the flower bud dormancy process in fruit trees still remains unknown. In this work, the AS profile of genes in the dormant flower buds of 'Dangshansu' pear tree were examined. A total number of 3661 alternatively spliced genes were identified, and three mRNA isoforms of the dormancy associated MADS box (DAM) gene, PpDAM1 , derived by alternative splicing, designated as PpDAM1.1 , PpDAM1.2 and PpDAM1.3 , were characterized. Bimolecular fluorescence complementation (BiFC) analysis indicated that AS of PpDAM1 didn't affect the nucleus localization and homo-/heterodimerization of PpDAM1.1, PpDAM1.2 and PpDAM1.3 proteins, but disturbed the translocation of PpDAM1.1/PpDAM1.1, PpDAM1.3/PpDAM1.3, PpDAM1.1/PpDAM1.3, and PpDAM1.2/PpDAM1.3 dimers to the nucleus. Constitutive expression of PpDAM1.2 , but not PpDAM1.1 and PpDAM1.3 , in Arabidopsis retarded the growth and development of transgenic plants. Further comparative expression analyses of PpDAM1.1 , PpDAM1.2 and PpDAM1.3 in the flower buds of 'Dangshansu' and a less dormant pear cultivar, 'Cuiguan', exhibited that the expression of all the three isoforms in 'Dangshansu' were significantly higher than in 'Cuiguan', especially PpDAM1.2 , which showed a predominantly higher expression than PpDAM1.1 and PpDAM1.3 in both cultivars. Our results suggest that alternative splicing of PpDAM1 could play a crucial role in pear flower bud dormancy process. • Three alternative spliced mRNA isoforms of PpDAM1 were detected in pear buds. • Constitutive expression of PpDAM1.2 retarded the growth and flowering in Arabidopsis. • PpDAM1.2 showed higher expression than PpDAM1.1/1.3 in different pear cultivars. [ABSTRACT FROM AUTHOR]

Background: HIV/AIDS has transformed into a chronic controllable but not yet curable infectious disease as other chronic diseases to some extent. The additional of so called fourth 90% that included the improved health-related quality of life (HRQoL) for people living with HIV (PLWHIV) required solutions beyond antiretroviral therapy and viral load suppression. This study will explore the role of personality, social economic and prevention strategy effection on HRQoL among people living with HIV/AIDS. Methods: A cross-sectional study was conducted among PLWHIV aged more than 16 years old in the 10 municipalities in Yunnan Province, China from October 2019 to May 2020, enrolling total 1997 participants. Individual-level HRQoL data were measured by 12-item Short Form Health Survey (SF-12) and EuroQol Five Dimensions Questionnaire (EQ-5D-5L). We assembled municipal-level data about social economic from Yunnan Statistical Yearbook in 2020 and strategy practice information from the self-evaluation system. We used the principal component analysis to build the social economic and strategy effect on each area respectively and one-way ANOVA was used to perform univariate analysis to identify the predictors with significant differences. Finally we used multi-level model (MLM) to explore the personality, social economic and strategy effects in health-related quality of life among PLWHIV. Results: The global score for quality of life measured using EQ-5D-5L had an estimated mean score (standard deviation, SD) of 0.901 ± 0.146. The HRQoL score measured using PCS-12 had an estimated mean score (SD) of 46.62 ± 8.55. The mean MCS-12 score (SD) was estimated to be 47.80 ± 9.71. The area-level predictors explained a proportion of 13.6–17.2% for the between-area variation of the HRQoL scores, regardless of the total HRQoL, physical component and mental component. The impacts of stigma (P < 0.01), social support (P < 0.001), anxiety (P < 0.001), depression (P < 0.05) and social economic status (P < 0.05) on HRQoL at the individual-level were significantly different. The plots visualized the impact of individual-level factors on a respondent's HRQoL was modified by the area-level characteristics. Conclusions: The study identified the possible strategy determinant of individual HRQoL of PLWHIV and also the area effect on HRQoL. Stigma, social support, anxiety, depression and social economic status were the individual-level determinants on HRQoL. These could be a valuable resource for evaluating the overall health of the areas and help improve local decision making. [ABSTRACT FROM AUTHOR]

Background: HIV/AIDS has transformed into a chronic controllable but not yet curable infectious disease as other chronic diseases to some extent. The additional of so called fourth 90% that included the improved health-related quality of life (HRQoL) for people living with HIV (PLWHIV) required solutions beyond antiretroviral therapy and viral load suppression. This study will explore the role of personality, social economic and prevention strategy effection on HRQoL among people living with HIV/AIDS. Methods: A cross-sectional study was conducted among PLWHIV aged more than 16 years old in the 10 municipalities in Yunnan Province, China from October 2019 to May 2020, enrolling total 1997 participants. Individual-level HRQoL data were measured by 12-item Short Form Health Survey (SF-12) and EuroQol Five Dimensions Questionnaire (EQ-5D-5L). We assembled municipal-level data about social economic from Yunnan Statistical Yearbook in 2020 and strategy practice information from the self-evaluation system. We used the principal component analysis to build the social economic and strategy effect on each area respectively and one-way ANOVA was used to perform univariate analysis to identify the predictors with significant differences. Finally we used multi-level model (MLM) to explore the personality, social economic and strategy effects in health-related quality of life among PLWHIV. Results: The global score for quality of life measured using EQ-5D-5L had an estimated mean score (standard deviation, SD) of 0.901 ± 0.146. The HRQoL score measured using PCS-12 had an estimated mean score (SD) of 46.62 ± 8.55. The mean MCS-12 score (SD) was estimated to be 47.80 ± 9.71. The area-level predictors explained a proportion of 13.6–17.2% for the between-area variation of the HRQoL scores, regardless of the total HRQoL, physical component and mental component. The impacts of stigma (P < 0.01), social support (P < 0.001), anxiety (P < 0.001), depression (P < 0.05) and social economic status (P < 0.05) on HRQoL at the individual-level were significantly different. The plots visualized the impact of individual-level factors on a respondent's HRQoL was modified by the area-level characteristics. Conclusions: The study identified the possible strategy determinant of individual HRQoL of PLWHIV and also the area effect on HRQoL. Stigma, social support, anxiety, depression and social economic status were the individual-level determinants on HRQoL. These could be a valuable resource for evaluating the overall health of the areas and help improve local decision making. [ABSTRACT FROM AUTHOR]

Potassium (K+) plays key roles in plant growth and development. However, molecular mechanism studies of K+ nutrition in forest plants are largely rare. In plants, SKOR gene encodes for the outward rectifying Shaker-type K+ channel that is responsible for the long-distance transportation of K+ through xylem in roots. In this study, we determined a Shaker-type K+ channel gene in purple osier (Salix purpurea), designated as SpuSKOR, and determined its function using a patch clamp electrophysiological system. SpuSKOR was closely clustered with poplar PtrSKOR in the phylogenetic tree. Quantitative real-time PCR (qRT-PCR) analyses demonstrated that SpuSKOR was predominantly expressed in roots, and expression decreased under K+ depletion conditions. Patch clamp analysis via HEK293-T cells demonstrated that the activity of the SpuSKOR channel was activated when the cell membrane voltage reached at -10 mV, and the channel activity was enhanced along with the increase of membrane voltage. Outward currents were recorded and induced in response to the decrease of external K+ concentration. Our results indicate that SpuSKOR is a typical voltage dependent outwardly rectifying K+ channel in purple osier. This study provides theoretical basis for revealing the mechanism of K+ transport and distribution in woody plants. [ABSTRACT FROM AUTHOR]

Background: We aim to describe the prevalence and trends of hypertension among 9-17 school-aged students from 2017 to 2019 in Yunnan, China.Methods: We conducted a cross-sectional study by using data from the Students' Health Surveillance Surveys of 2017, 2018 and 2019 in Yunnan. The Students' Health Surveillance Surveys in Yunnan collected date on physical fitness and health status of students in Yunnan through multistage-stratified sampling in 3 prefectures. In each prefecture, the study population were classified by gender and region (urban or rural), and each group had an equal size. Diagnosing criteria of hypertension was set with reference to Chinese age-specific and height-specific blood pressure (BP), to identify the abnormal status of boys and girls separately. ANOVA test was adopted to measure the differences in the mean BP stratified by gender, age, prefecture and area, and Chi-square test was used to compare the percentages of hypertension in different areas. For comparability, the age-standard and gender-standard population prevalence was calculated by directly using China Census in 2010 as a standard population. Totally 24,890 participants aged 9-17 years were included in this study.Results: From 2017 to 2019, there were 24,872 students completed physical examinations and included in the analysis, of which 3288 were diagnosed with hypertension. The total prevalence of hypertension was 13.72, 12.49 and 13.45% among 9-17 years school-aged population in Yunnan, respectively. The total age-standardized hypertension prevalence trended to decrease from 13.82 to 13.48%. For urban population, the age-standardized hypertension prevalence decreased slightly from 11.24 to 10.13%. While, for rural population, it increased from 17.58 to 19.16%. The average annual growth rate in rural population was 0.53%.Conclusions: From 2017to 2019, there was a significant and continuous increase in the prevalence of hypertension in 9-17 years school-aged population in Yunnan. Hypertension is epidemic among children and adolescents in Yunnan. We should take effective and comprehensive intervention measures to reduce its prevalence among school-aged children. [ABSTRACT FROM AUTHOR]

The storage period of European pear (Pyrus communis L.) is prolonged at low temperature, but the pear softened quickly after shifting to room temperature. However, the molecular mechanisms that influence this process are unknown. In this study, 'Docteur Jules Guyot' pears were placed at room temperature (RT) and low temperature and then turned to room temperature (LR). The fruit firmness of 'Docteur Jules Guyot' under LR decreased faster than RT after moving from low temperature. The ethylene production rate, water-soluble pectin (WSP), ionic-soluble pectin (ISP) content, and pectin degradation enzyme activity of 'Docteur Jules Guyot' under LR increased faster than RT after moving from low temperature. RNA-seq of 'Docteur Jules Guyot' pear under different storage conditions was carried out, and 1018 genes were found to be negatively correlated with fruit firmness by the weighted gene coexpression network analysis (WGCNA) method. Then, 24 structural genes and transcription factors related to fruit softening were selected to verify the RNA-Seq results. The expression of all these selected genes increased significantly after LT storage. The fruit firmness, pectin content, and pectin degradation enzyme activity of 'Laiyang' pear did not change significantly under RT and LR storage conditions. The expression of LAX2 , ARF19 , EXP1 , EXPA1 , EXP3 and PG2 was upregulated in 'Docteur Jules Guyot' pear but downregulated in 'Laiyang' pear. These genes might play important roles in the softening process of European pear. This work laid the foundation for revealing the mechanisms of European pear fruit softening. • Low temperature accelerated the softening of 'Docteur Jules Guyot' pear after shifting to room temperature. • WGCNA identifies two key modules involved in pear fruit softening. • The expression trend of some genes in European and Asian pears was completely opposite. • LAX2 , ARF19 , EXP1 , EXPA1 , EXP3 and PG2 may play important roles in European pear softening. [ABSTRACT FROM AUTHOR]

Fruit aroma is an important evaluation index for fruit quality. Linoleic acid is an essential precursor pool for the aroma compounds in peach (Prunus persica L.) and is catalyzed by fatty acid desaturase 2 (FAD2). In this study, PpFAD2–1 and PpFAD2–2 were isolated from 'Jinxiuhuangtao' peaches. Three typical conserved histidine motifs (HX3or4H, HX2or3HH, and HX2or3HH) were observed in the two PpFAD2 proteins, and 18 candidate amino acid residues potentially involved in fatty acid desaturation were identified in PpFAD2–1. Subcellular localization analysis indicated that PpFAD2s are localized in endoplasmic reticulum membrane. Notably, PpFAD2–1 expression was gradually increased during the fruit ripening stages, whereas PpFAD2–2 changed little. In vitro enzyme assay in both Escherichia coli and yeast revealed that PpFAD2s increased linoleic acid levels, with a larger increment of PpFAD2–1 than that of PpFAD2–2. Furthermore, in vivo enzyme activity assay revealed that levels of two unsaturated fatty acids (linoleic acid and linolenic acid) and peach aroma compounds (including hexyl acetate, γ-dodecalactone, γ-decalactone, γ-octalactone and γ-hexalactone) were increased in PpFAD2–1 transgenic fruit during postharvest storage, especially under recovery storage in room temperature after cold storage (4 ℃), whereas unchanged in PpFAD2–2 transgenic fruit. Favorably, this study provides new insights into the role of PpFAD2s in regulating peach aroma biosynthesis, which contributes to the sustainable fruit storage management and the molecular breading of new peach varieties with more favorable aromas. • Two FAD2 genes were isolated from high aroma peach cultivar 'Jinxiuhuangtao'. • In vitro expression of PpFAD2-1 in E. coli or yeast increased linoleic acid content. • In vivo expression of PpFAD2-1 increased unsaturated fatty acids in transgenic fruit. • In vivo expression of PpFAD2-1 induced aroma compounds in transgenic fruit. [ABSTRACT FROM AUTHOR]

Ammonium (NH4+) plays key roles in plant growth, development, fruit quality, and yield. In plants, NH4+ uptake and transport are facilitated by NH4+ transporters (AMT). However, molecular mechanisms and physiological functions of type-II AMT (AMT2) transporters in fruit trees are still unclear, especially in peach. In this study, we cloned and characterized an AMT2 family gene from peach, PpeAMT3;4, and determined its function in yeast mutant. Expression analysis showed that PpeAMT3;4 was majorly expressed in peach roots and significantly decreased by NH4+ excess but had no response to NH4+ deficiency. Functional determination and 15nitrogen-labeled NH4+ uptake assay in yeast cells implied that PpeAMT3;4 was a typical high-affinity transporter, with a K m value of 86.3 μM, that can uptake external NH4+ in yeast cells. This study provides gene resources to uncover the biological function of AMT2 transporters and reveals molecular basis for NH4+ uptake and nitrogen (N) nutrition mechanisms in fruit trees. [ABSTRACT FROM AUTHOR]

The K+ transporter/high-affinity K+/K+ uptake (KT/HAK/KUP) transporters dominate K+ uptake, transport, and allocation that play a pivotal role in mineral homeostasis and plant adaptation to adverse abiotic stresses. However, molecular mechanisms towards K+ nutrition in forest trees are extremely rare, especially in willow. In this study, we identified 22 KT/HAK/KUP transporter genes in purple osier willow (designated as SpuHAK1 to SpuHAK22) and examined their expression under K+ deficiency, drought, and salt stress conditions. Both transcriptomic and quantitative real-time PCR (qRT-PCR) analyses demonstrated that SpuHAKs were predominantly expressed in stems, and the expression levels of SpuHAK1, SpuHAK2, SpuHAK3, SpuHAK7, and SpuHAK8 were higher at the whole plant level, whereas SpuHAK9, SpuHAK11, SpuHAK20, and SpuHAK22 were hardly detected in tested tissues. In addition, both K+ deficiency and salt stress decreased the tissue K+ content, while drought increased the tissue K+ content in purple osier plant. Moreover, SpuHAK genes were differentially responsive to K+ deficiency, drought, and salt stresses in roots. K+ deficiency and salt stress mainly enhanced the expression level of responsive SpuHAK genes. Fifteen putative cis-acting regulatory elements, including the stress response, hormone response, circadian regulation, and nutrition and development, were identified in the promoter region of SpuHAK genes. Our findings provide a foundation for further functional characterization of KT/HAK/KUP transporters in forest trees and may be useful for breeding willow rootstocks that utilize potassium more efficiently. [ABSTRACT FROM AUTHOR]

As one of the most important micronutrients, iron (Fe) plays a critical role in various metabolic processes during plant growth and development. However, the molecular mechanisms towards Fe metabolism and nutrition in fruit trees are largely unknown. In this study, we examined the effects of amino acid-Fe compound fertilizer spraying on leaf development in peach (Prunus persica (L.) Batsch) at different developmental stages. Foliar spraying with amino acid-Fe compound fertilizer did not cause any significant changes in leaf morphology but remarkably increased leaf fresh weights. Fe concentration, photosynthetic parameter, and Fe-S protein analyses revealed that Fe accumulation, total chlorophyll content, net photosynthetic rate ( P N ), and stomatal conductance ( g s ), as well as nitrite reductase (NIR) and succinate dehydrogenase (SDH) activities, were significantly higher in the leaves sprayed with amino acid-Fe compound fertilizer than in the control leaves sprayed with distilled water. Further quantitative real-time PCR (qRT-PCR) analyses demonstrated that Fe-S cluster biosynthesis genes were differentially expressed in the leaves at different developmental stages. Foliar spraying with amino acid-Fe compound fertilizer significantly increased the expression of the most tested Fe-S cluster biosynthesis genes. Our findings provide new insights into the understanding of effects of Fe fertilization application on leaf development in perennial woody fruit trees. [ABSTRACT FROM AUTHOR]

Background: The characteristics of recent HIV infections can provide the information about the dynamics of HIV transmission. Yunnan is one of the provinces hardest-hit by HIV-1 in China. To further understand the characteristics of the HIV-1 epidemic in Yunnan, we analyzed the prevalence of recent HIV-1 infections among newly diagnosed cases, identified the associated factors and explored the spatial distribution of recent HIV-1 infections.Methods: Residual plasma samples from HIV-1 diagnostic tests were preserved. The associated information was collected from China HIV/AIDS case reporting system. Recent HIV-1 infections were estimated by combining the information about disease progression and BED- capture enzyme immunoassay (CEIA). The proportions of recent HIV-1 infections among newly diagnosed cases stratified by demographic characteristics were analyzed. The spatial clusters of recent HIV-1 infections were investigated by spatial scan statistics.Results: Among 6119 HIV/AIDS cases were newly reported between January 2015 and June 2015 in Yunnan Province, 9.3% (570/6119) were estimated as recent infections. Female, aged below 25 years and homosexual contact were more associated with the higher proportion of recent HIV-1 infections. Among the different demographic sub-groups, men who have sex with men (MSM) aged < 25 years and ≥ 50 years had a higher chance of being diagnosed as recent infections, heterosexually infected men aged ≥25 years had a lower chance of being diagnosed as recent infections. In the sub-groups with different screening approaches, the highest proportion of recent infections (16.1%) was found among women diagnosed by testing during pregnancy and childbirth. In the sub-groups with different contact histories, the higher proportion of recent infections was found among the female cases having commercial heterosexual contacts (16.4%) and MSM (19.7%). The statistically significant spatial clusters of recent infections attributed to heterosexual contact, homosexual contact and intravenous drug injection were identified, respectively.Conclusions: The investigation of recent HIV infections among newly diagnosed cases supplements the routine HIV surveillance, and reveals the characteristics of ongoing HIV transmission. Our finding identified the potential sub-populations and geographic areas in need of services or improved interventions. [ABSTRACT FROM AUTHOR]

Background: HCV genotype 6 (HCV-6) typically circulates in Southeast Asia and exhibits the highest genetic diversity among the eight HCV genotypes. In our previous work, a group of HCV-6 sequences was not clearly classified. Here, we further characterized this HCV-6 variant and analyzed the evolutionary history of the enlarged HCV-6 family. Methods: Blood samples from eight HCV seropositive samples collected from intravenous drug users (IDUs) in 2014 in Yunnan Province, China. The full-length HCV genome sequences were amplified by using reverse transcription PCR followed by DNA sequencing and phylogenetic analysis. Bayesian evolutionary analysis was performed with the complete coding region sequences of subtype 6a-6xh. Results: The eight genomes had the same coding region of 9051 nucleotides. The complete coding region sequences of the eight HCV isolates formed a distinct phylogenetic group from the previously assigned HCV-6 subtypes (6a-6xf), however which clustered with 6xg reference sequences that were found in Kachin State, Myanmar, and recently assigned and released. The p-distances of the eight isolates to subtype 6a-6xf and 6xh ranged from 0.143 to 0.283. Based on the HCV-6 complete coding region sequences, we constructed a timescaled phylogenetic tree to reveal the HCV-6 evolutionary history, in which there were four HCV-6 phylogenetic subsets, whose median tMRCAs were 294.8, 388.5, 348.5 and 197.0 years ago, respectively. Subtype 6xg clustered into Subset I, and had the most recent common ancestor with subtype 6n, which dated back to 101.2 (95% HPD: 78.7, 125.8) years ago. The genetic evolutionary analysis further confirmed that subtype 6xg originated from Myanmar, and transmitted to Dehong through cross-border IDUs. Conclusion: The HCV-6 variant characterized in this study belonged to newly assigned subtype 6xg. Our finding further confirmed the assignment of 6xg. HCV-6 family was highly divers and had a complicated evolutionary history in Southeast Asia. It is necessary to further characterize HCV-6 genetics in this region. [ABSTRACT FROM AUTHOR]

The third plague pandemic originated from Yunnan Province, China in the middle of the 19th century. The last human plague epidemic in Yunnan occurred from 1986–2005. On June 6, 2016, a case of human plague was reported in the Xishuangbanna Prefecture, Yunnan. The patient suffered from primary septicemic plague after exposure to a dead house rat (Rattus flavipectus), which has been identified as the main plague reservoir in the local epizootic area. Moreover, a retrospective investigation identified another bubonic plague case in this area. Based on these data, human plague reemerged after a silent period of ten years. In this study, three molecular typing methods, including a clustered regularly interspaced short palindromic repeats (CRISPR) analysis, different region analysis (DFR), and multiple-locus variable number of tandem repeats analysis (MLVA), were used to illustrate the molecular characteristics of Yersinia pestis (Y. pestis) strains isolated in Yunnan. The DFR profiles of the strains isolated in Yunnan in 2016 were the same as the strains that had previously been isolated in this Rattus flavipectus plague focus. The c3 spacer present in the previously isolated strains was absent in the spacer arrays of the Ypc CRISPR loci of the strains isolated in 2016. The MLVA analysis using MLVA (14+12) showed that the strains isolated from the human plague case and host animal plague infection in 2016 in Yunnan displayed different molecular patterns than the strains that had previously been isolated from Yunnan and adjacent provinces. [ABSTRACT FROM AUTHOR]

Background: Yunnan has the greatest share of reported human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) cases in China. In recent years, HIV prevalence and incidence remained stubbornly high in men who have sex with men (MSM). To follow the dynamics of the HIV-1 epidemic among MSM, HIV-1 genetic characteristics and genetic transmission networks were investigated. Methods: Blood samples from 190 newly diagnosed HIV-1 cases among MSM were continuously collected at fixed sites from January 2013 to December 2015 in Kunming City, Yunnan Province. Partial gag, pol and env genes were sequenced and used for phylogenetic and genotypic drug resistance analyses. The genetic characteristics of the predominant HIV-1 strains were analyzed by the Bayesian Markov Chain Monte Carlo (MCMC) method. The genetic transmission networks were identified with a genetic distance of 0.03 substitutions/site and 90% bootstrap support. Results: Among the 190 HIV-1 positive MSM reported during 2013–2105, various genotypes were identified, including CRF01_AE (45.3%), CRF07_BC (35.8%), unique recombinant forms (URFs) (11.6%), CRF08_BC (3.2%), CRF55_01B (2.1%), subtype B (1.6%) and CRF59_01B (0.5%). The effective population sizes (EPS) for CRF01_AE and CRF07_BC increased exponentially from approximately 2001–2010 and 2005–2009, respectively. Genetic transmission networks were constructed with 308 pol sequences from MSM diagnosed during 2010–2015. Of the 308 MSM, 109 (35.4%) were identified in 38 distinct clusters. Having multiple male partners was associated with a high probability of identification in the genetic transmission networks. Of the 38 clusters, 27 (71.1%) contained individuals diagnosed in different years. Of the 109 individuals in the networks, 26 (23.9%) had ≥2 potential transmission partners (≥2 links). The proportion of MSM with ≥2 links was higher among those diagnosed from 2010–2012. The constituent ratios of their potential transmission partners by areas showed no significant difference among MSM from Kunming, other cities in Yunnan and other provinces. Additionally, surveillance drug resistance mutations (SDRMs) were identified in 5% of individuals. Conclusion: This study revealed the various HIV-a genotypes circulating among MSM in Kunming. MSM with more partners were more easily detected in transmission networks, and early-diagnosed MSM remained active in transmission networks. These findings suggested that the routine interventions should be combined with HIV testing and linkage to care and early antiretroviral therapy among HIV-positive MSM. [ABSTRACT FROM AUTHOR]

The basic helix-loop-helix (bHLH) transcription factor family is a superfamily found in all eukaryotes that plays important roles in regulating growth and development. Over the past several decades, many bHLH superfamily genes have been identified and characterized in herbaceous and woody plants. However, the genes belonging to the bHLH superfamily in peach (Prunus persica) have not yet been comprehensively identified and characterized. Here, we identified 95 members of the bHLH superfamily in the peach genome, and these genes were classified into 19 subfamilies based on a phylogenetic comparison with bHLH proteins from Arabidopsis. The members within each subfamily were highly conserved according to the analysis of motif compositions and exon/intron organizations. The 95 bHLH genes were unevenly distributed on chromosomes 1 to 8 of the peach genome. We identified 57 pairs of bHLH members that were orthologous between peach and Arabidopsis. Additionally, 48 pairs of paralogous bHLH genes were identified on the eight chromosomes of the peach genome. Coupled with relative expression analysis of bHLH genes in red-fleshed peach fruit at five developmental stages, we identified several bHLH genes that might be involved in fruit development and anthocyanin biosynthesis. This study provides insight into the molecular mechanisms through which these genes are involved in the regulation of biological and biochemical processes in peach and lays the foundation for further studies on these genes. [ABSTRACT FROM AUTHOR]

Plague, caused by Yersinia pestis, was classified as a reemerging infectious disease by the World Health Organization. The five human pneumonic plague cases in Yulong County in 2005 gave rise to the discovery of a Yulong plague focus in Yunnan province, China. Thereafter, continuous wild rodent plague (sylvatic plague) was identified as the main plague reservoir of this focus. In this study, the epizootics in Yulong focus were described, and three molecular typing methods, including the different region (DFR) analysis, clustered regularly interspaced short palindromic repeats (CRISPRs), and the multiple-locus variable number of tandem repeats (VNTR) analysis (MLVA) (14+12), were used for the molecular typing and source tracing of Y. pestis isolates in the Yulong plague focus. Simultaneously, several isolates from the vicinity of Yunnan were used as controls. The results showed that during the 10-year period from 2006 to 2016, an animal plague epidemic occurred in 6 of those years, and 5 villages underwent an animal plague epidemic within a 30-km2 area of the Yulong plague focus. Searching for dead mice was the most effective monitoring method in this plague focus. No positive sample has been found in 6937 captured live rodents thus far, suggesting that the virulence of strains in the Yulong plague focus is stronger and the survival time of mice is shorter after infection. Strains from Lijiang, Sichuan and Tibet were of the same complex based on a typing analysis of DFR and CRISPR. The genetic relationship of Y. pestis illustrated by MLVA “14+12” demonstrates that Tibet and Sichuan strains evolved from the strains 1.IN2 (Qinghai, 1970 and Tibet, 1976), and Lijiang strains are closer to Batang strains (Batang County in Sichuan province, 2011, Himalaya marmot plague foci) in terms of genetic or phylogenic relationships. In conclusion, we have a deeper understanding of this new plague focus throughout this study, which provides a basis for effective prevention and control. [ABSTRACT FROM AUTHOR]

Harvest maturity is closely related to peach fruit quality and has a very important effect on the fresh fruit market. Unfortunately, at present, it is difficult to determine the maturity level of peach fruits by artificial methods. The objectives of this study were to develop quadratic polynomial regression models using near-infrared spectroscopy that could determine the peel color difference, fruit firmness, soluble solids content (SSC), soluble sugar, organic acid components, and their relationships with the absorbance of chlorophyll (index of absorbance difference, IAD) in late maturing ‘Xiahui 8’ peach and ‘Xiaguang’ nectarine fruits. The analysis was based on data for fruits at veraison, fruits at harvesting maturity, and all fruits. The results showed that firmness has the highest correlation coefficient with IAD. Prediction models for fruit maturity were established between firmness and the IAD of the two cultivars using the quadratic polynomial regression method. Further variance analysis on the one degree term and quadratic term of each equation showed that every partial regression coefficient reached a significant or extremely significant level. No significant difference was observed between estimated and observed values after regression prediction. The regression equations seem to fit well. Other peach and nectarine varieties were used to test the feasibility of maturity prediction by this method, and it was found that maturity was successfully predicted in all the samples. The result indicated that the IAD can be used as an index to predict peach fruit maturity. [ABSTRACT FROM AUTHOR]

• Transcriptome sequencing of the branches of 'Bartlett' and 'Red Bartlett'. • Weighted gene coexpression network analysis (WGCNA) identified 495 differentially expressed genes positively associated with anthocyanin. • The expression levels of one UFGT and one GST were also upregulated in the pericarps of 'Red Bartlett' and 'Starkrimson' than in 'Bartlett' and 'Clapps Favourite'. The color of the peel is the most direct reflection of fruit quality, and is also an important factor in attracting consumers. The 'Red Bartlett' pear (Pyrus communis L.) is a red bud sport mutant variety of 'Bartlett' pear. It was found that the anthocyanin content in branches and pericarps of 'Red Bartlett' pears were significantly higher than that of 'Bartlett' pears. The present study aimed to clarify the underlying mechanisms of anthocyanin accumulation in 'Red Bartlett' using a transcriptome analysis. A weighted gene coexpression network analysis (WGCNA) identified 495 differentially expressed genes positively associated with anthocyanin. Additionally, 12 anthocyanin-related structural genes and 13 transcription factors, including WRKY, ERF, bHLH, ASIL2, and HSF, were identified through screening of 495 DEGs. The expression levels of one UFGT (Pbr014258.1) and one GST (Pbr012649.1) were also upregulated in the pericarps of 'Red Bartlett' and 'Starkrimson', more so than in 'Bartlett' and 'Clapps Favourite'. Overall, this study clarified that the red color mutation of 'Red Bartlett' was closely linked to increased anthocyanin biosynthesis and transport. This study provided an abundance of valuable information on anthocyanin biosynthesis for future breeding of red-skinned pears. [ABSTRACT FROM AUTHOR]

Manganese (Mn) toxicity in soil is a widely observed phenomenon, which seriously restricts growth, quality, and yield of various crops and fruits including apples. However, mechanisms underlying the regulation of polyamines (PAs) by brassinosteroids (BRs) to improve tolerance to Mn stress are still unclear. In this study, we investigated the effects of 2,4-epibrassinolide (EBL; a BR) on the expression of genes involved in BR signaling pathway, Mn accumulation, PAs-mediated responses (PA precursor levels, metabolic enzymes, and genes), and growth parameters in Mn-stressed Malus robusta Rehd. EBL application significantly modulated the expressions of genes related to BR signaling (MdBRI , MdBSK , etc.) and reduced Mn accumulation, along with improving the rate of increase in root length and plant height, relative water content, chlorophyll content, maximum photochemical efficiency of PSII (Fv/Fm), and actual photochemical efficiency (Φ PSII) and decreasing electrical conductivity. Furthermore, EBL application significantly reduced putrescine (Put) accumulation and increased spermine (Spm) content and (Spd + Spm)/Put ratio. EBL weakened ornithine (Orn) pathway, decreased ornithine decarboxylase (ODC) activity, and increased biosynthesis of Spm from Put via elevating the PA oxidase (PAO) activity and expression of MdSPDS , MdSPMS , and MdPAO. The trends for free, PS-conjugated, and PIS-bound PAs were similar to that of total PAs, except that no significant change was observed in free Spm, PS-conjugated Spd, and Spm, as well as PIS-bound Spd. This study revealed that BR-regulated PAs help in mitigating Mn toxicity and clarified the mechanisms of regulation of PAs by BRs in apple trees. • EBL application significantly activated the expressions of genes related to BR signaling. • Mn accumulation was significantly reduced after EBL application. • EBL application improved growth parameters and physiological indexes in M. robusta under Mn toxicity. • The strategy to overcome Mn stress was highly associated with the stimulation of PAs profile by BRs. • The mechanism of regulation of PAs by BRs against Mn stress was provided. [ABSTRACT FROM AUTHOR]

The correct reference 2 should be: Algaralleh A, Altwalbeh D, Al-Tarawneh F. Health-related quality of life among persons living with HIV/AIDS in Jordan: an exploratory study. Correction to: Infect Dis Poverty (2021) 10:104 https://doi.org/10.1186/s40249-021-00890-9 Following publication of the original article [[1]], it was found that the authors' first name and family name are interchanged in the second reference of the article. [Extracted from the article]

Abstract: A protein microarray containing 144 known or putative virulence-related proteins of Yersinia pestis was used to evaluate the antibody responses of plague patients. Forty-two proteins were found to be expressed in vivo and antibodies against 14 of them were detected in all patients analyzed, providing potential candidates for novel protective antigens and novel serodiagnostic markers in Y. pestis. Moreover, the lack of antibody to LcrV in the five patients in Focus F might be a challenge to our understanding of the pathogenesis of Y. pestis. [Copyright &y& Elsevier]

Extracellular ATP (eATP) has long been established in animals as an important signalling molecule but this is less understood in plants. The identification of Arabidopsis thaliana DORN1 (Does Not Respond to Nucleotides) as the first plant eATP receptor has shown that it is fundamental to the elevation of cytosolic free Ca2+ ([Ca2+]cyt) as a possible second messenger. eATP causes other downstream responses such as increase in reactive oxygen species (ROS) and nitric oxide, plus changes in gene expression. The plasma membrane Ca2+ influx channels involved in eATP-induced [Ca2+]cyt increase remain unknown at the genetic level. Arabidopsis thaliana Annexin 1 has been found to mediate ROS-activated Ca2+ influx in root epidermis, consistent with its operating as a transport pathway. In this study, the loss of function Annexin 1 mutant was found to have impaired [Ca2+]cyt elevation in roots in response to eATP or eADP. Additionally, this annexin was implicated in modulating eATP-induced intracellular ROS accumulation in roots as well as expression of eATP-responsive genes. [ABSTRACT FROM AUTHOR]

Soil amendments (e.g., hydrochar) have recently gained increasing research interest because of their potential application in agricultural soils to reduce nutrient loss to the environment. In order to improve the surface properties of hydrochar, we herein used the microbial-aging approach to produce microbially-aged hydrochar (M-SHC), which was applied in rice paddy soil columns to investigate nitrogen transformation processes and gaseous nitrogen losses by NH 3 volatilization. The aim of this research was mainly to explore and understand the mechanisms by which sawdust hydrochar (SHC), M-SHC, and water-washed hydrochar (W-SHC) influence NH 3 volatilization in rice paddy fields. Compared with the control, M-SHC treatment considerably reduced both cumulative NH 3 and yield-scale NH 3 volatilization by 11.52% and 24.40% (p < 0.05), respectively. This reduction could be attributed to a decrease in NH 4 +–N concentrations and an alteration of floodwater pH, following the application of M-SHC. The results showed that changes in floodwater pH could considerably affect the NH 3 volatilization rate. When floodwater was slightly alkaline (pH > 7.25), even a minor alteration of pH following the application of hydrochar could increase NH 3 volatilization rapidly. The application of hydrochar substantially inhibited the soil urease activity and increased the soil amoA gene abundance, which, in turn, decreased the floodwater NH 4 +–N concentrations. These results offer strong theoretical support for the application of hydrochar in agricultural systems to decrease NH 3 volatilization in rice paddy fields. Note: BF, SF1, SF2 represent the basal fertilization, the first supplementary fertilization, the second supplementary fertilization respectively. Image 1 • Hydrochar was aged in a fermentation system and it was applied in rice paddy soil. • Microbially-aged hydrochar (M-SHC) significantly reduced NH 3 volatilization. • M-SHC reduced yield-scale NH 3 volatilization by 24.40% compared with CKU. • Microbially-aging process increased hydrochar's pore volume by 145.49%. • M-SHC reduced soil urease activity and elevated the abundance of amoA gene. [ABSTRACT FROM AUTHOR]

Background: As a gateway for HIV-1 in China, Yunnan has experienced dramatic changes in HIV-1 epidemics, during which HIV-1 genotypes have become complex. To track dynamic changes in HIV-1 genotypes, an HIV-1 molecular epidemiological study was implemented in the recently infected population in Yunnan.Methods: From 6,357 HIV-1-positive samples diagnosed during the first half of 2015 in Yunnan, 586 samples were identified as recent infections with BED-capture enzyme immunoassay (CEIA) and were subjected to phylogenetic analyses. Spatial scanning analyses for the main HIV-1 genotypes were also performed.Results: Among the 439 specimens successfully genotyped, more than ten genotypes were detected, including CRF08_BC (45.3%), CRF07_BC (19.4%), unique recombinant forms (URFs) (18.2%), CRF01_AE (11.4%), subtype C (2.1%), CRF85_BC (1.1%), CRF55_01B (0.9%), subtype B (0.5%), CRF64_BC (0.5%), CRF59_01B (0.2%), CRF83_cpx (0.2%) and CRF87_cpx (0.2%). Females, Chinese, heterosexual contact and intravenous drug injection were significantly associated with CRF08_BC infection; homosexual contact was significantly associated with CRF01_AE and CRF07_BC infection; males and non-Chinese had a higher risk of URF infection than females. Among all HIV-1 genotypes, the geographic coverage of CRF08_BC was the largest. For CRF08_BC, CRF07_BC, URFs and CRF01_AE, spatial clusters were detected. The two CRF08_BC clusters and one URF cluster were associated with heterosexual transmission, and two of CRF01_AE clusters were associated with homosexual transmission. Transmitted drug resistance (TDR)-associated mutations were detected in 2.4% of individuals.Conclusions: The diversity of HIV-1 genotypes increased in recent infections because of a long-term HIV-1 epidemic in Yunnan. The predominant HIV-1 strains showed distinct demographic characteristics and formed spatial clusters. These findings improved our understanding of the evolution of HIV-1 in Yunnan and provided information for further HIV-1 control and prevention. [ABSTRACT FROM AUTHOR]