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Key message: A stable QTL qSW_Gm10 works with a novel locus, qSW_Gm01, in a synergistic manner for controlling slow-wilting traits at the early vegetative stage under drought stress in soybean. Drought is one of the major environmental factors which limits soybean yield. Slow wilting is a promising trait that can enhance drought resilience in soybean without additional production costs. Recently, a Korean soybean cultivar SS2-2 was reported to exhibit slow wilting at the early vegetative stages. To find genetic loci responsible for slow wilting, in this study, quantitative trait loci (QTL) analysis was conducted using a recombinant inbred line (RIL) population derived from crossing between Taekwangkong (fast-wilting) and SS2-2 (slow-wilting). Wilting score and leaf moisture content were evaluated at the early vegetative stages for three years. Using the ICIM-MET module, a novel QTL on Chr01, qSW_Gm01 was identified, together with a previously known QTL, qSW_Gm10. These two QTLs were found to work synergistically for slow wilting of the RILs under the water-restricted condition. Furthermore, the SNP markers from the SoySNP50K dataset, located within these QTLs, were associated with the wilting phenotype in 30 diverse soybean accessions. Two genes encoding protein kinase 1b and multidrug resistance-associated protein 4 were proposed as candidate genes for qSW_Gm01 and qSW_Gm10, respectively, based on a comprehensive examination of sequence variation and gene expression differences in the parental lines under drought conditions. These genes may play a role in slow wilting by optimally regulating stomatal aperture. Our findings provide promising genetic resources for improving drought resilience in soybean and give valuable insights into the genetic mechanisms governing slow wilting. [ABSTRACT FROM AUTHOR]

This paper considers the prescribed-time leader-following consensus problem of input-constrained linear multi-agent systems under generally directed communication topology in two cases: the Laplacian matrix related to the entire communication topology between agents is either known or unknown. In particular, the consensus problem for the former case is solved by a novel bounded linear time-varying (LTV) protocol, where the feedback gain is formulated by the parametric Lyapunov equation and the knowledge of the Laplacian matrix. Moreover, by utilizing a distributed observer, a fully bounded LTV protocol is proposed for the latter case. It should be noted that, compared with the existing results, the system under consideration is more general, the designed protocols are linear, and the consensus problem is accomplished even in a fully distributed manner. Finally, the effectiveness of the proposed approach is verified by a numerical example. [ABSTRACT FROM AUTHOR]

Drought stress is the major environment constraint on soybean yield, and a variety of pathways underlie drought tolerance mechanisms. Transcriptomic profiling of two soybean cultivars, drought-tolerant SS2-2 and drought-sensitive Taekwang, was performed under normal and drought conditions to identify genes involved in drought tolerance. This revealed large differences in water loss during drought treatment. Genes involved in signaling, lipid metabolism, phosphorylation, and gene regulation were overrepresented among genes that were differentially expressed between cultivars and between treatments in each cultivar. The analysis revealed transcription factors from six families, including WRKYs and NACs, showed significant SS2-2-specific upregulation. Genes involved in stress defense pathways, including MAPK signaling, Ca2+ signaling, ROS scavenging, and NBS-LRR, were also identified. Expression of non-specific phospholipases, phospholipase D, and PHOSPHATIDYL INOSITOL MONOPHOSPHATE 5 KINASE (PIP5K), which act in the lipid-signaling pathway, was greatly increased in SS2-2. The roles of PIP5K in drought stress tolerance were confirmed in Arabidopsis thaliana. Arabidopsispip5k mutants had significantly lower survival rates under drought stress than wild-type plants. This study identified additional elements in the mechanisms used by plants to protect themselves from drought stress and provides valuable information for the development of drought-tolerant soybean cultivars. [ABSTRACT FROM AUTHOR]

As a class I carcinogen, arsenic has been reported to cause diseases accompanied by circRNAs regulating proliferation and apoptosis at the molecular level, but whether circP50 (circBase ID: hsa_circ_0008012) does the same has not been demonstrated. The aim of this study is to provide the basis for anti-lung cancer mechanism research, by studying the expression of circP50 under arsenic-induced conditions, and the effect and mechanism on the proliferation and apoptosis of A549 cells based on the circP50 knockdown models. To explore whether the circP50 is responsive to arsenic exposure, the qRT-PCR was applied to discover that the relative expression of circP50 in A549 cells increased only with increasing NaAsO2 dose and independent of its metabolites. We further determined the mechanism of circP50 by establishing circP50 knockdown models. The results of cell viability and EdU assays indicated the proliferation of A549 cells. According to the western blotting, phosphorylation of p53 at Ser15, Ser376, and Ser392 and acetylation of p53 at Lys370 and Lys382 were inhibited, resulting in the deficiency of p53 expression. Subsequently, the expression of genes downstream of p53 was reduced, including p21, PUMA, Caspase3, and Bcl-xS. Furthermore, the expressions of IKB-α, p65, and p50 decreased, but C-myc expression did not change significantly, referring to the NF-κB pathway was not dominant. The results suggest that circP50 mainly functions through the p53 pathway to mediate apoptosis in response to arsenic exposure. [ABSTRACT FROM AUTHOR]

Osteosarcoma is a primary malignant tumor that often metastasizes in orthopedic diseases. Although multi-drug chemotherapy and surgical treatment have significantly improved the survival and prognosis of patients with osteosarcoma, the survival rate is still very low due to frequent metastases in patients with osteosarcoma. In-depth exploration of the relationship between various influencing factors of osteosarcoma is very important for screening promising therapeutic targets. This study used multivariate COX regression analysis to select the hypoxia genes SLC2A1 and FBP1 in patients with osteosarcoma, and used the expression of these two genes to divide the patients with osteosarcoma into high-risk and low-risk groups. Then, we first constructed a prognostic model based on the patient's risk value and compared the survival difference between the high expression group and the low expression group. Second, in the high expression group and the low expression group, compare the differences in tumor invasion and inflammatory gene expression between the two groups of immune cells. Finally, the ferroptosis-related genes with differences between the high expression group and the low expression group were screened, and the correlation between these genes was analyzed. In the high-risk group, immune cells with higher tumor invasiveness, macrophages M0 and immune cells with lower invasiveness included: mast cell resting, regulatory T cells (Tregs) and monocytes. Finally, among genes related to ferroptosis, we found AKR1C2, AKR1C1 and ALOX15 that may be related to hypoxia. These ferroptosis-related genes were discovered for the first time in osteosarcoma. Among them, the hypoxia gene FBP1 is positively correlated with the ferroptosis genes AKR1C1 and ALOX15, and the hypoxia gene SLC2A1 is negatively correlated with the ferroptosis genes AKR1C2, AKR1C1 and ALOX15. This study constructed a prognostic model based on hypoxia-related genes SLC2A1 and FBP1 in patients with osteosarcoma, and explored their correlation with immune cells, inflammatory markers and ferroptosis-related genes. This indicates that SLC2A1 and FBP1 are promising targets for osteosarcoma research. [ABSTRACT FROM AUTHOR]

Key message: Synchronous pod maturity is critical for increasing grain yield. The candidate genes involved in synchronous pod maturity were identified through RNA-seq and HPLC. Mungbean (Vigna radiata [L.] Wilczek), an important source of carbohydrate and protein in Asia, is characterized by nonsynchronous pod maturity; consequently, harvesting is labor intensive. Because pod maturity is associated with synthesis and remobilization of sucrose, we examined changes in sucrose levels and transcriptome in leaf (source) tissues after pod (sink) removal using two genotypes, VC1973A and V2984; VC1973A had higher synchronicity in pod maturity than V2984. After pod removal, much higher number of pods were produced in V2984 than VC1973A. The sucrose content of leaf tissues significantly decreased in V2984 because it continued to utilize assimilates from leaves for producing new pods, but significantly increased in VC1973A because of the loss of sink. Transcriptome analysis revealed that the number of differentially expressed genes was approximately fourfold higher in VC1973A than in those of V2984 after pod removal. The expression of two paralogous genes (Vradi01g05010 and Vradi10g08240), encoding beta-glucosidase enzymes, significantly decreased in VC1973A after pod removal and was significantly lower in depodded VC1973A than depodded V2984, indicating these two genes may participate in sucrose utilization for seed development by regulating the level of glucose. The results of this study will help elucidate the genetic basis of synchronous pod maturity in mungbean and facilitate the development of new cultivars with synchronous pod maturity. [ABSTRACT FROM AUTHOR]

Variation in winter temperature is less well understood than in annual and summer temperatures over long timescales, particularly in low-latitude (0–30° N) montane regions with large spatial and topographic heterogeneity. Understanding these variations could be critical for forest manageemnt in these important tree growing regions. We collected tree-ring cores from Yunnan Province in montane southwest China, to determine how winter temperature has varied in the past and to explore its possible drivers in this region. Six highly correlated site chronologies were combined into a long and well-replicated regional composite (RC) chronology. The RC chronology correlated strongest with mean early winter season temperature (EWST) from November to January during 1959–2015. We applied RC chronology to reconstruct EWST from 1653 to 2015. The reconstruction shows five relatively warm historic intervals (1658–1718, 1743–1755, 1771–1791, 1929–1959, and 1995–2015) and cold intervals (1720–1742, 1792–1852, 1860–1883, 1905–1928, and 1960–1994). The 1950s with six anomalous warm seasons and 1980s with five anomalous cold seasons were the warmest and coldest decades, respectively. The EWST reconstruction generally agreed with other winter temperature reconstructions from nearby areas and with historical documents. Atlantic Multidecadal Oscillation (AMO) might be a key forcing of multidecadal winter temperature variations in montane southwest China over the past three and half centuries. Both warm and cold temperature periods coincide with respective positive and negative phases of AMO. Besides, the cold intervals during the nineteenth and twentieth centuries may also have been influenced by large volcano eruptions in low-latitude regions of south and east Asia. Our EWST reconstruction not only improves our understanding of the trends and variations of winter climate history, but also supports planning for resilience in conservation, agriculture, and forestry management in montane southwest China into the future. [ABSTRACT FROM AUTHOR]

Accurate three-phase identification from Solid Oxide Fuel Cell (SOFC) anode micrograph is challenged by both noise and intensity inhomogeneity. In this paper, a novel framework is proposed for porous Ni-YSZ cermet anode Optical Microscopy (OM) image segmentation. The proposed framework takes advantage of a statistical model in which an observed image is decomposed into two multiplicative components (bias field and true image) and one additive component (noise). A two-stage Principal Component Analysis with Local Pixel Grouping (LPG-PCA) denoising algorithm is firstly performed to suppress additive noise, it can preserve more image local structural features by modeling a pixel and its nearest neighbors as a vector variable and selecting training samples with similar contents to this variable in a local window for PCA transformation. In order to enhance the robustness to noise, uneven illumination and other outliers, a kernel metric is introduced into fuzzy clustering method embedded with bias field correction for image segmentation. The proposed method has been compared to other state-of-the-art segmentation algorithms on both simulated images and real SOFC anode OM images. Extensive experiments results have demonstrated that the proposed framework can successfully eliminate the influence of both uneven illumination and noise on real Ni/YSZ anode OM images to obtain a better three-phase identification accuracy. The high-quality segmentation results lay firm foundation for accurate microstructural parameter extraction. [ABSTRACT FROM AUTHOR]

This paper takes the thick and widely distributed crystal dolomite of Xixiangchi Formation, Upper Cambrian in Southeastern Sichuan basin as an example, the reservoir characteristics and main controlling factors of crystal dolomite have been analyzed systematically, and the genesis and reservoir formation mechanism of crystal dolomite have been discussed. It shows that the main reservoir rocks of crystal dolomite include powder crystalline dolomite and finely crystalline dolomites, and the intercrystal pores and dissolved intercrystal pores are the main reservoir spaces, with few dissolved vugs and fractures developed in the reservoir. The pore structure analysis shows that the throats of crystal dolomite reservoir are mainly lamellar, reflecting a good configuration between pores and throats, medium- low porosity and low permeability, representing typical porous-type reservoir. Dolomitization analysis indicates that the dolomitization occurred in the penecontemporaneous or early diagenetic stage. The degree of dolomitization decreased gradually from the top to the bottom in each sedimentary cycle, and distribution of dolomite in the study area shows that the content of dolomites decreases from the west to the east, which reflects the degree of dolomitization weakening eastward. Combined with the geochemical research of crystal dolomite, the C and O isotope data reflect the same characteristics of seawater during the late Cambrian. It indicates that the dolomitization might be related to the seepage-reflux of seawater in the early time. Recrystallization played an important role in the genesis of the crystal dolomite, because most of crystal dolomites remain residual granular texture. The intercrystal pores formed by seepage–reflux dolomitization acted as superior seepage channels for the reservoir transformation, and the recrystallization adjusted the previous pores and made them better, while the karstification was the key to the dissolved pore formation. [ABSTRACT FROM AUTHOR]

Longwangmiao Formation in Lower Cambrian is one of the key petroleum systems in Sichuan basin. The reservoir is well developed in the Longwangmiao Formation which was deposited in the restricted carbonate platform. It is indicated that the karstification occurred in the reservoir of Longwangmiao Formation during the Caledonian tectonic movement on the basis of seismology, petrology, sedimentology and geochemistry. Distinguishable markers of the paleo-karstification include: the lost strata and unconformable contact occurring between Middle-Upper Cambrian carbonates and Lower Permian Liangshan Formation; the occurrence of collapse breccias and fillings in caves and karrens; the evident difference between cave fill dolostones and matrix dolomite in the Sr/Ba ratio; and the log response of cavernous formations. The karstification lasted for a long time. According to the residual thickness between the top of Longwangmiao Formation and the bottom of the Permian, paleo-geomorphology during the Caledonian karstification had been recovered. In that time, Longwangmiao Formation was not directly exposed to the surface in central Sichuan basin; lots of meteoric fresh water flowed through faults and cracks from Gaotai Formation and a series of vertical dissolved caverns and karrens were formed. Meanwhile, due to the denudation window of Leshan-Longnvsi paleo-uplift lying in the west of the study area, meteoric fresh water flowed from the denudation window and the Longwangmiao Formation became a karstic confined aquifer. Under the pressure, diagenetic fluid migrated along the formation. Consequently, elongated dissolved pores and vugs formed and bedding karst reservoir developed in Longwangmiao Formation. The intensity of the karstification weakened with the distance from the paleo-uplift increasing, which indicates that the karstification was deeply influenced by the paleo-uplift. Finally, the supergene karstification model of Longwangmiao Formation has been established on the basis of the synthesis of the above-mentioned research results. [ABSTRACT FROM AUTHOR]

Changes in minimum winter temperature (MWT) and their potential effects on plant growth and development have been gaining increased scientific attention. To better understand these changes across long temporal scales, the present study used dendroclimatological techniques to assess variations in MWT in Southwestern China. Using data from Rhododendron species distributed in areas above the tree-line, a regional composite chronology was generated for a 341-year period. Based on the significant negative correlation between MWT values and ring-width, the most reliable parts of this chronological data were then used to reconstruct MWT values for the past 211 years. This reconstructed MWT series showed decadal to multi-decadal fluctuations. Three distinct cold periods prevailed during 1823-1858, 1882-1891 and 1922-1965, while four warm intervals occurred in 1800-1822, 1858-1881, 1892-1921 and 1966-2011. Our reconstructed MWT reveals a warming trend over the most recent eight decades, which is in agreement with instrumental observations. However, the MWT values and rate of warming over the past seven decades did not exceed those found in the reconstructed temperature data for the past 211 years. Spatial correlations reveal that the MWT in Southwest China is strongly associated with regional temperatures in the Eastern and Central Himalaya, Northern China, and the Indian Peninsula. Larger scale climate oscillations of the Western Pacific and Northern Indian Ocean as well as the North Atlantic Oscillation probably influenced the region's temperature in the past. [ABSTRACT FROM AUTHOR]

The Lower Cambrian Longwangmiao Formation shoal dolostone reservoir in Sichuan Basin is currently an exploration and research highlight in China. Reservoir rocks mainly consist of crystalline dolomite with residual grain texture, and dolarenite of which the arene is mainly composed of muddy to micritic dolomite with some crystalline grain directionally aligned. The trace element indicates that the dolomites of Longwangmiao Formation may be related to the high salinity of sea water. The oxygen isotope values of crystalline dolomite and dolarenite are both similar to that of the Early Cambrian marine dolomites, and the carbon isotope values of every kind of dolomites are completely overlapped with that of the seawater in Early Cambrian, indicating the dolomitization fluid is originated from the Early Cambrian sea water. The restricted marine biological communities and a small amount of gypsum pseudonodule seen in muddy to micritic dolomite indicate that the sea water in Early Cambrian was restricted and evaporated. However, the general lack of massive evaporite mineral and gypsum karst breccia indicates that the salinity of sea water during dolomitization was lower than the value of gypsum's precipitation. The Longwangmiao Formation consists of several high-frequency sedimentary cycles, indicating frequent sea level changes. This study indicates that massive dolomitiza-tion may also occur in underwater palaeohigh in carbonate platform through the reflux of penesaline sea water driven by a combination of high- and low-frequency sea-level changes. This kind of dolomiti-zation can explain the generation of massive dolomites in the absence of evaporite precipitation, and further indicates that replacement dolomites can be produced by sea water with a wide range of salinity (normal, penesaline to hypersaline). [ABSTRACT FROM AUTHOR]

It is indicated in this paper that the karstification occurred in Block 12 of Tahe oilfield during Early Hercynian stage on the basis of identification features obtained through the latest research on seismology, petrology, and geochemistry. Distinguishable markers of the paleo-karstification mainly include: the lost strata and unconformable contact occurring between Lower-Middle Ordovician carbonates and Lower Carboniferous Bachu Formation, the occurrence of collapse breccias and fillings in subsurface stream, the evident difference between cave-fill calcite and matrix carbonate in the Sr/Ba ratio, and the log response for cavernous formations. The paleo-geomorphology of Early Hercynian karstification can be divided into four units: karst highland, I- and II-level karst slope, and karst basin in Tahe area, and the Block 12 was basically located in II-level karst slope. Three karst cycles developed in the Block 12 according to Early Hercynian tectonism characterized by multiphase pulse-type uplift movement and three sets of cavernous formation formed. II- and III-level cavernous formations mainly developed in Block 12. The Early Hercynian karstification is distributed on the north area of the pinch-out line of Upper Ordovician Sangtamu Formation in the plane, and is vertically developed in the Lower-Middle Ordovician carbonates. The karstification is essentially controlled by the paleo-geomorphology and fault. Fissures and caves formed by the karstification are the keys to affecting reservoir quality. The evolution model of Early Hercynian karstification has been established on the basis of the synthesis of the above-mentioned research results. It can be divided into three stages: rapidly uplifting and denudation stage, three episodes of uplifting and karstification, and subsiding and reworking stage. [ABSTRACT FROM AUTHOR]

Houba oil sand in frontier Longmenshan Mountain is one of the most typically important unconventional resources. The basic reservoir characteristics of oil sand and the main factors affecting reservoir quality were examined in this article based on porosity, permeability, and mercury porosimetry measurements; thin section analyses; SEM observation; and X-ray diffraction analysis. This study shows that the oil-bearing sandstone reservoir is mainly medium−coarse-grained sublitharenite and litharenite. The main pore type is intergranular pores, including residual primary intergranular pores, dissolved intergranular pores, and dissolved intragranular pores; fractures are common in this study area. The quality of sandstone reservoir is of high porosity and high permeability with a high oil saturation of 89.84 %. It is indicated that the main controlling factors of the reservoir in the study area include deposition, diagenesis, and tectonism. Deposition laid a foundation to porosity evolution, and channel sand is the most favorable depositional facies for the reservoir. Diagenetic alterations are the keys to reservoir evolution; dissolution and chlorite coatings cementation play an effective role in the generation and preservation of pores. Compaction, carbonate cementation, and quartz overgrowth cause many damages to the reservoir porosity. Fractures caused by structural breakages can improve the reservoir permeability and they also can provide fluid migration pathways to the late corrosion, which formed a lot of corroded fissures as reservoir and percolation spaces. [ABSTRACT FROM AUTHOR]

Experimental forest plantations to study biodiversity-ecosystem functioning (BEF) relationships have recently been established in different regions of the world, but subtropical biomes have not been covered so far. Here, we report about the initial survivorship of 26 tree species in the first such experiment in subtropical China. In the context of the joint Sino-German-Swiss Research Unit 'BEF-China,' 271 experimental forest plots were established using 24 naturally occurring tree species and two native commercial conifers. Based on the survival inventories carried out in November 2009 and June 2010, the overall survival rate was 87 % after the first 14 months. Generalized mixed-effects models showed that survival rates of seedlings were significantly affected by species richness, the species' leaf habit (deciduous or evergreen), species identity, planting date, and altitude. In the first survey, seedling establishment success decreased with increasing richness levels, a tendency that disappeared in the second survey after replanting. Though evergreen species performed less well than deciduous species with establishment rates of 84 versus 93 % in the second survey, their planting success exceeded the general expectation for subtropical broad-leaved evergreen species. These results have important implications for establishing mixed-species plantations for diversity conservation and improvement of ecosystem functioning in the Chinese subtropics and elsewhere. Additional costs associated with mixed-species plantations as compared to conventional plantations also demonstrate the potential of upscaling BEF experiments to large-scale afforestation projects. [ABSTRACT FROM AUTHOR]

Climate change affects various facets of life but there is little data on its effects on wild mushroom fruiting. Yunnan Province in China is a rich source of wild mushrooms and has experienced a temperature rise over recent decades. This has resulted in warmer temperatures but the impacts of these changes on mushroom production lack documentation. We collected data on the fruiting of the highly prized matsutake mushroom ( Tricholoma matsutake) in West Yunnan, China over an 11 year period from 2000 to 2010. Fruiting phenology and productivity were compared against the driving meteorological variables using Projection to Latent Structure regression. The mushrooms appeared later in the season during the observation period, which is most likely explained by rising temperatures and reduced rain during May and June. High temperature and abundant rain in August resulted in good productivity. The climate response of matsutake production results from a sequence of processes that are possibly linked with regulatory signals and resource availability. To advance the knowledge of this complex system, a holistic research approach integrating biology, ecology, genetics, physiology, and phytochemistry is needed. Our results contribute to a general model of fungal ecology, which can be used to predict the responses of fungi to global climate change. [ABSTRACT FROM AUTHOR]

Mushrooms can be found in forests worldwide and have long been exploited as resources in developed economies because of their important agro-industrial, medicinal and commercial uses. For less developed countries, such as those within the Greater Mekong Subregion, wild harvesting and mushroom cultivation provides a much-needed alternative source of income for rural households. However, this has led to over-harvesting and ultimately environmental degradation in certain areas, thus management guidelines allowing for a more sustained approach to the use of wild mushrooms is required. This article addresses a selection of the most popular and highly sought after edible mushrooms from Greater Mekong Subregion: Astraeus hygrometricus, Boletus edulis, Morchella conica, Ophiocordyceps sinensis, Phlebopus portentosus, Pleurotus giganteus, Termitomyces eurhizus, Thelephora ganbajun, Tricholoma matsuake, and Tuber indicum in terms of value, ecology and conservation. The greatest threat to these and many other mushroom species is that of habitat loss and over-harvesting of wild stocks, thus, by creating awareness of these issues we wish to enable a more sustainable use of these natural products. Thus our paper provides baseline data for these fungi so that future monitoring can establish the effects of continued harvesting on mushroom populations and the related host species. [ABSTRACT FROM AUTHOR]

Yuanmou County in Yunnan Province, China is situated in a dry hot valley where annual evaporation is almost six times the annual rainfall and thus the county suffers from chronic water shortages. Since the early 1980s the county has taken advantage of local warm climate and focused its economic development strategy on commercial vegetable plantations. This strategy successfully brings high income to the local government and farmers, but increases water consumption and adds an extra stressor to the already diminished water resources. Yuanmou County is one of the endemic fluorosis hotspots in China where both dental and skeletal fluorosis cases have been found among local villagers that were diagnosed as being water-borne. Despite measures to adapt to water shortages and control fluorosis taken by the local government and communities, new challenges are emerging. Herein, we describe the water management challenges facing the county as well as document the coping strategies adopted by the government and communities, analyze remaining and emerging challenges, and suggest an ecohealth framework for better management of water resources in Yuanmou. [ABSTRACT FROM AUTHOR]

In China, many rural communities depend upon forests to provide wood, fuel, fertilizer, animal bedding, and valuable non-timber forest products (NTFP). However, the degree to which forest resource extraction is compatible with new conservation aims is unclear because there is little information on the specific ecological effects of traditional forest collecting practices. Therefore, we compared the structure and floristics of Pinus densata forests exposed to three levels of resource extraction by Tibetan villages in northwest Yunnan: (1) a forest site protected from wood and timber removal, (2) moderately utilized forest sites exposed to traditional collecting practices, and (3) patches of highly utilized forest from which timber extraction is high in response to recent development pressures. The results show that understorey and cryptogamic species are reduced in all the utilized forest sites by comparison with the protected forest. However, the moderately utilized pine forests still provide good NTFP habitats by maintaining relatively high canopy covers, litter covers, and understorey structural complexity; this suggests that traditional forest resource use, while simplifying the forest, does not pose an increasing threat to pine forest integrity. By comparison, the highly utilized forests are transformed into open, herb-rich environments in which canopy covers and understorey complexity are depleted, and NTFP habitats are degraded. In the future it may be practical to enhance biodiversity by proscribing forest resource collection, but the immediate priority is to monitor the sustainability of forest utilization using indicators such as understorey development, litter cover, and cryptogamic richness. [ABSTRACT FROM AUTHOR]

The study of land bridge based on continental drift and long-distance dispersal are gaining increasing attention in biogeography. We review several major dispersal theories including the Malpigiaceae route, patterns of chameleon dispersal and the floating island model. The Malpigiaceae route indicates that the Malpigiaceae family originated in northern South America and that members of several clades migrated into North America and subsequently moved via north Atlantic land connections into the Old World starting in the Eocene. This route may also explain many other pantropic disjunction patterns, including some Chinese plants disjunctions, involving South America. Not all biogeographical distribution patterns can be explained by vicariance theory, so more research, including chameleon distribution, has recently focused on long-distance dispersal. The latest analyses suggest that chameleons have dispersed over long-distances from Madagascar on several occasions. The floating island model would explain flora and fauna similarities between South America and Africa. Studying long-distance dispersal mechanisms is important for understanding distribution patterns and even the spread of pandemics. More research on the specific implications of long-distance dispersal for biogeography is necessary. [ABSTRACT FROM AUTHOR]

Coumestrol (CMS), a coumestan isoflavone, plays key roles in nodulation through communication with rhizobia, and has been used as phytoestrogens for hormone replacement therapy in humans. Because CMS content is controlled by multiple genetic factors, the genetic basis of CMS biosynthesis has remained unclear. We identified soybean genotypes with consistently high (Daewonkong) or low (SS0903-2B-21-1-2) CMS content over 2 years. We performed RNA sequencing of leaf samples from both genotypes at developmental stage R7, when CMS levels are highest. Within the phenylpropanoid biosynthetic pathway, 41 genes were tightly connected in a functional co-expression gene network; seven of these genes were differentially expressed between two genotypes. We identified 14 candidate genes involved in CMS biosynthesis. Among them, seven were annotated as encoding oxidoreductases that may catalyze the transfer of electrons from daidzein, a precursor of CMS. Two of the other genes, annotated as encoding a MYB domain protein and a MLP-like protein, may increase CMS accumulation in response to stress conditions. Our results will help to complete our understanding of the CMS biosynthetic pathway, and should facilitate development of soybean cultivars with high CMS content that could be used to promote the fitness of plants and human beings. [ABSTRACT FROM AUTHOR]

Antibiotic administration, while facilitating clearance of targeted infections, also perturbs commensal microbial communities. Previous studies have all focused on the effects of short term use of antibiotics. Here, we focus on the effects of long term use of antibiotic on gut microbiota and immunity. BALB/c mice received saline or different doses of ceftriaxone sodium (100, 200 and 400 mg/mL) via daily gavage for 150 days. Alterations of fecal microbiota, small intestine histopathology, body weight, spleen index, serum IgG, mucus SIgA, IFN-γ/IL-4 ratio, CD4/CD8 ratio and CD4+CD25+ cells were evaluated. Long term ceftriaxone sodium administration resulted in gut microbiota dysbiosis, intestine histological lesions, growth inhibition, spleen index reducing. The immune defense ability reduced as serum IgG and mucus SIgA decreased significantly. Not only the immune defense, long term ceftriaxone administration also affected immune regulation. The IFN-γ/IL-4 and CD4/CD8 ratios increased, the CD4+CD25+ cells reduced on days 30 and 60 after ceftriaxone administration. However, after 90 days of ceftriaxone administration, the IFN-γ/IL-4, CD4/CD8 ratios and CD4+CD25+ cells restored, which indicated a new balance of immune regulation had been formed. Overall, these findings contribute to our understanding of long term antibiotic administration influencing gut microbiota and immunity. [ABSTRACT FROM AUTHOR]