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The PCE of Cs2PbX4–WSe2 heterostructures is larger than the PCE of Cs2PbX4–MoSe2 heterostructures. Cs2PbI4–WSe2 heterostructure has the largest PCE (18%) among Cs2PbX4–MSe2 heterostructures and has great potential application in solar cells.

With the increase of drilling depth, the mechanical properties of H-section steel used in drilling platform are more and more demanding. In this paper, the strength, low temperature impact toughness, plasticity, micro-hardness and microstructure of 500MPa hot rolled H-section steel produced by TMCP process were analyzed, and the strengthening mechanism was also studied. The results show that flanges of TMCP hot rolled H-section steel had the best strength and toughness, while the yield strength at web and R Angle was reduced to 91% and 78% of the flange, respectively. The impact toughness at -40°C of web and R Angle was reduced to 86% and 38% of the flange , and the micro-hardness reduced to 91% and 85% of the flange, respectively. The main strengthening mechanism of the TMCP hot rolled H-section steel is fine-grain strengthening, the carbonitride of V precipitation strengthening and surface bainite transformation strengthening.

Epoxy coatings and Reduced Graphene Oxide (RGO) modified epoxy coatings were prepared on N80 tubing steel. The influence of temperature on the corrosion resistance of RGO modified epoxy coatings was studied. And the corrosion behavior of epoxy coatings and RGO modified epoxy coatings in 10.0 wt% NaCl solution at different temperatures was compared. The results showed that the corrosion resistance of both coatings decreased with the increase of temperature. However, the corrosion resistance of RGO modified epoxy coating was two to three orders of magnitude higher than that of epoxy coating at different test temperature. The addition of RGO nanosheets greatly enhanced the corrosion resistance of epoxy composite coatings in 10.0 wt% NaCl solution at high temperature due to their high impermeability and negative coefficient of thermal expansion.

Objective Early-onset dementia (EOD) is a relatively uncommon form of dementia that afflicts people before age 65. Only a few studies analyzing the genetics of EOD have been performed in the Chinese Han population. Diagnosing EOD remains a challenge due to the diverse genetic and clinical heterogeneity of these diseases. The aim of this study was to investigate the genetic spectrum and clinical features of Chinese patients with EOD. Materials and methods A total of 49 EOD patients were recruited. Targeted next-generation (NGS) analyses were performed to screen for all of the known genes associated with dementia. Possible pathogenic variants were confirmed by performing Sanger sequencing. The genetic spectrum and clinical features of the EOD patients were analyzed. Results Seven previously reported pathogenic variants (p.I213T and p.W165C in PSEN1; p.D678N in APP; c.1349_1352del in TBK1; p.P301L and p.R406W in MAPT; p.R110C in NOTCH3) and two novel variants of uncertain significance (p.P436L in PSEN2; c.239-11G>A in TARDBP) were identified. Conclusion Our study demonstrated the genetic spectrum and clinical features of EOD patients, and it reveals that genetic testing of known causal genes in EOD patients can help to make a precise diagnosis.

Casing radial deformation during complex fracturing process was seriously for shale gas wells in Sichuan district of China, and the average casing deformation rate in the region is of 50%. The bridge plug, perforating gun and other tools cannot successfully pass with deformed casing. Aiming at the 3-D logging morphology for deformed casing of shale gas wells, the failure modes and mechanisms were analyzed by using elasticity and theoretical mechanics. Many factors were evaluated and integrated to achieve quantitative evaluation model including geology feature, wellbore trajectory, cement property, casing material and hydrofracture process. With the aid of the self-developed unconventional oil and gas well casing simulation test equipment, the casing bearing capacity with shear load were carried out, established the relationship between shear load value and radial deformation, and further constructed the casing failure criterion with shear force. This work can provide technical support for casing design and selection in shale gas wells.

During acidizing process in a gas field, leakage of 80SS anti-sulfur tubing occurred.The main reasons for failure of the tubing have been investigated based on analysis techniques of chemical composition analysis,Optical Microscopy (OM), Scanning Electron Microscope (SEM), Energy Dispersive Spectrometer (EDS) , X-ray Diffraction (XRD) and mechanical test. The results show that composition and mechanical properties of the tubing were all in accordance with the corresponding requirements of API Spec 5CT standards. Furthermore,leakage of tubing from inner wall was caused by combined impacts of acid corrosion, H2S corrosion, low PH value, high temperature and a certain pressure. Meanwhile, Low concentration of corrosion inhibitor was also one of the factors of corrosion perforation.

Graphene modified coatings have attracted extensive attention in recent years due to their excellent corrosion resistance and broad application prospects in the field of anti-corrosion. However, large-scale applications of graphene coatings were seldom reported, which is mainly attributed to the lack of fundamental research on the anti-corrosive mechanism and the long-term service performance evaluation of graphene modified coatings in actual working conditions. In the present work, the influence of the characteristics of corrosive medium, the content of graphene, the structure and morphology of graphene and the external environmental conditions on the anti-corrosive performance of graphene modified coatings were systematically reviewed. The deficiencies in the research of anti-corrosive performance of graphene modified coatings were summarized. The future work were prospected for the anti-corrosive performance and applications of graphene modified coatings in oil and gas exploration.

Corrosion leakage became serious due to cyclic sewage injection and continuous increase in water injection pressure. Corrosion behavior for N80 casing was studied during long-term service, using corrosion reaction kettle and weight loss method. The morphology and composition were characterized with laser confocal microscopy (LCM), scan electron microscopy (SEM) and energy disperse spectroscopy (EDS). These results showed that corrosion rate remained constantly at initial stage, and increased gradually, then sharply reached to 0.327mm/a at later stage, accompanying with inflection point under oxygen condition. Meanwhile, corrosion rate decreased significantly from 0.028mm/a to 0.020mm/a under oxygen-free condition. The corrosion of N80 steel was dominated by dissolved oxygen, and accelerated by chloridion. The micro-mechanism was suggested to be the transition of defect structure from crack with micron range to etch pit with millimeter range.

During heavy oil production, the performance of casing varies with temperature in the service environment. The tensile test of N80Q Steel and 80SH Steel were carried out to evaluate the mechanical properties during the service. The results indicated that the grain size of 80SH steel was relatively uniform and the grain boundary was relatively obvious compared with N80Q steel. A qualitative analysis was performance by relating the tensile properties with different temperature. The results showed that the yield strength, the tensile strength and elongation of N80Q and 80SH steels decreased with increasing temperature, but the degree of decline was limited. The observation of the tensile fracture revealed that the characteristics of the radiation zone of N80Q steel were obvious compared with 80SH steel at 20°C.

The main exploitation process of heavy oil is cyclic steam huff and puff. Cyclic operation causes cumulative damage to thermal recovery casing and causes a large number of failures. Failure analysis shows that the main failure factor of thermal recovery casing is the low cycle fatigue process caused by thermal cycle, which results in the decrease of strength of casing material, thus causing casing fracture and failure. Based on the failure analysis results, the low cycle fatigue tests of 80SH thermal recovery casing steel under different temperature, strain, pre-strain and other conditions were carried out. The influencing factors, life prediction model and criterion of service safety of casing materials under thermal recovery service conditions were first proposed, which provides a strong theoretical basis for the service safety design theory of thermal recovery casing materials. The research shows that the strain limit and low cycle fatigue life are the two core issues of service life. Life predictions need to satisfy two criteria. The first is the strain criterion. The strain limit should be lower than the total strain during the long service life. And the second is the low cycle fatigue criterion, which satisfies the expectation of low cycle fatigue life under double conditions of strain amplitude and mean strain.

In view of the external thread fracture during casing running in a well in Xinjiang Oilfield, the failure reasons of thread fracture were analyzed by combining the theory with experiment, and the casing safe service window with harsh working conditions was given. The operation of the failed casing and determined the actual working conditions of the casing threaded joints during the running process were investigated in this paper. According to the theoretical method, the boundary conditions and load conditions of the fracture casing joint in service were determined. With the aid of full-scale physical simulation test device, as well as the above boundary conditions and load conditions, the same batch casing tensile bearing characteristics were determined. Through nondestructive testing, the metallographic observation, scanning electron microscopy, spectral analysis and up-and-down test, the main controlling factors of casing thread fracture were determined. By the finite element analysis, the casing threads service state under axial tension and bending loads was established, the safety performance of threads under ideal working conditions was studied, and the fatigue mechanism of threads was revealed. Combined with the analysis results, the corresponding relationship between the casing tensile bearing characteristics and safety factor was given, which provides technical support for the safe service selection of casing body and thread under harsh conditions, saving cost and shortening the well construction period.

Tylopilus jiangxiensis is described as a new species characterized by its small basidiomata, yellowish brown pileal and stipe surface, pallid to pinkish hymenophore, smooth stipe surface and white context without color change when bruised. Molecular phylogenetic analyses based on five gene makers (ITS, nrLSU, tef1-α, rpb1 and rpb2) confirmed it as a novel member of the genus Tylopilus s. str. Its morphological descriptions and illustrations are provided.

Ethylene insensitive 3 (EIN3), a key transcription factor in ethylene signal transduction, play important roles in plant stress signaling pathways. In this study, we isolated and characterized an EIN3-like gene from cotton (Gossypium hirsutum), designated as GhEIN3. GhEIN3 is highly expressed in vegetative tissues, and its expression is induced by 1-aminocyclopropane-1-carboxylic acid (ACC) and NaCl. Ectopic expression of GhEIN3 in Arabidopsis elevated plants' response to ethylene, which exhibit smaller leaves, more root hairs, shorter roots and hypocotyls. The germination rate, survival rate and root length of GhEIN3 transgenic plants were significantly improved compared to wild type under salt stress. GhEIN3 transgenic plants accumulated less H2O2 and malondialdehyde (MDA), while higher superoxide dismutase (SOD) and peroxidase (POD) activities were detected under salt stress. In addition, expression of several genes related to reactive oxygen species (ROS) pathway and ABA signaling pathway was increased in the GhEIN3 transgenic plants under salt stress. In contrast, virus-induced gene silencing (VIGS) of GhEIN3 in cotton enhanced the sensitivity of transgenic plants to salt stress, accumulating higher H2O2 and MDA and lower SOD and POD activities compared to control plants. Collectively, our results revealed that GhEIN3 might be involved in the regulation of plant response to salt stress by regulating ABA and ROS pathway during plant growth and development.

For unconventional oil and gas well perforating technology, field complex fracturing process to carry out the casing perforation physical simulation test, determine the different perforating process corresponding to the aperture size morphology, based on this, according to the physical simulation test results, perforating casing finite element model is established, the analysis of stress concentration around the perforation under different construction conditions, determine the outer extrusion safety factor, for complex oil and gas field casing string design and provide technical support. Keywords: complex fracturing;perforation; casing; mechanical properties

Shale gas well casing deformation failure is extremely serious in complex fracturing process. Based on the elastic mechanics theory, the distribution law of casing’s maximum equivalent stress field with the non uniform external extrusion is calculated by the complex variable function method. Meanwhile, casing deformation failure mechanism with non uniform external extrusion is revealed. For another, the maximum equivalent stress of the casing is analyzed with the case of a/b=2 and a/b=5. The result shows that the unevenness of the extrusion load has a great influence on the casing maximum equivalent stress distribution. The findings provide technical support for casing design and selection in complex fracturing process of shale gas well. Keywords: shale gas well; complex fracturing; casing formation; failure mechanism

In the present work, a self-built device called “full scale tubular goods erosion-corrosion test system” was used to test the P110SS tubing with a total length of 10 m and a full scale PFF78-70 flat valve to study their erosion-corrosion behaviors in the acceleration simulation operating condition of a well in Sichuang oil field of China. The erosion-corrosion performance of the specimen was investigated by KH-7700 digital microscope, scanning electron microscopy (SEM), X-ray power diffraction (XRD) and energy-dispersive spectroscopy (EDS). The results indicated that the P110SS tubing suffered catastrophic erosion-corrosion; the maximum pitting corrosion rate of the P110SS in the gas phase fluid was 5.29mm/a; while that in the liquid phase fluid was 11.13mm/a; A double-layer corrosion products scale, inner FeCO3 layer and outer mixture layer mainly dominated by FeO, Fe3O4, Fe2O3 and FeO(OH), formed on the P110SS tubing. Erosion-corrosion only occurred in the stress concentration area of the valve plate hole of the PFF78-70 plate valve, and the size of the corrosion pits is about 0.5mm.

A new modified low-cost titanium alloy, Ti-Al-X, was designed for petroleum drilling applications. The alloy ingots were prepared by combination of vacuum consumable electrode arc melting, forging/hot rolling, homogenization, and solid-solution/aging treatments. The hot deformation behavior of Ti-Al-X alloy was investigated by a thermal simulation machine Gleeble 1500 at temperature range of 850~1000°C with the strain rate range of 0.001 s-1~1s-1. The deformation resistance significantly decreases with the increase of deformation temperature and the strain rate. The alloy exhibits flow instability under the deformation conditions of strain rates about 0.001 s-1 and temperature above 1000°C, which should be avoided during hot working. In addition, the instability area enlarged in processing map with the increasing of true strain.

In this paper, in view of the problem of tubing corrosion in the water injection well, it is proposed to use the aluminizing N80 tubing to improve the corrosion problem. An aluminized layer with a thickness of about 150 μm was prepared on the surface of commonly used N80 tubing. The electrochemical polarization test at room temperature and the high temperature autoclave test for simulated water injection well environment were carried out on both of the aluminized and non-aluminized N80 tubing. It is intended to provide a feasibility test basis for the application of aluminized tubing in water injection wells by comparing the corrosion resistance performance of the aluminized and non-aluminized N80 tubing. The results showed that the aluminized layer on the surface of N80 tubing had good adhesion due to the mutual diffusion layer, and the thickness of the aluminized layer can reach 150μm. Compared with the non-aluminized N80 tubing, the self-corrosion current density of the aluminized N80 tubing polarization curve decreased obviously in the water injection well environment, and the corrosion rate in the high temperature autoclave test was also reduced to one quarter of that of the non-aluminized N80 tubing.

The service conditions of thermal recovery wells make the casing repeatedly bear the tension and compression load and form low cycle fatigue. Meanwhile, many factors, such as pre-strain and creep, lead to the formation of asymmetrical low cycle fatigue (R≠-1), which is the low cycle fatigue behavior under the influence of mean strain. This work studied the effect of mean strain on low cycle fatigue behavior of N80Q steel. Different strain amplitude conditions were selected for low cycle fatigue test, which were 0.5%, 0.7%, 1.0%, 1.5% and 2.0% respectively. Then tests at mean strains of-0.8%, 0%, 0.5% and 1.0% were conducted under constant strain amplitude. And the microstructure and fracture surface of the material after the tests were characterized using scanning electron microscopy and transmission electron microscopy, respectively. The results show that the mean strain makes the fatigue life reduce significantly under the condition of constant strain amplitude, and is related to the amplitude of the mean strain. The value of the mean strain and the strain amplitude will ultimately affect the fatigue life. And the fatigue life is related to the maximum absolute value of strain and has a linear relationship in the double logarithmic coordinate system. The SEM results of fracture morphology show that the brittleness feature of the crack growth area with high mean strain decreases significantly. And the fracture cross-section observation shows that the crack propagation is transgranular propagation. The TEM results show that a large number of dislocations pile-up is formed at lath subgrain boundary.

The Pleurotus ostreatus species complex is saprotrophic and of significant economic and ecological importance. However, species delimitation has long been problematic because of phenotypic plasticity and morphological stasis. In addition, the evolutionary history is poorly understood due to limited sampling and insufficient gene fragments employed for phylogenetic analyses. Comprehensive sampling from Asia, Europe, North and South America and Africa was used to run phylogenetic analyses of the P. ostreatus species complex based on 40 nuclear single-copy orthologous genes using maximum likelihood and Bayesian inference analyses. Here, we present a robust phylogeny of the P. ostreatus species complex, fully resolved from the deepest nodes to species level. The P. ostreatus species complex was strongly supported as monophyletic, and 20 phylogenetic species were recognized, with seven putatively new species. Data from our molecular clock analyses suggested that divergence of the genus Pleurotus probably occurred in the late Jurassic, while the most recent common ancestor of the P. ostreatus species complex diversified about 39 Ma in East Asia. Species of the P. ostreatus complex might migrate from the East Asia into North America across the North Atlantic Land Bridge or the Bering Land Bridge at different times during the late Oligocene, late Miocene and late Pliocene, and then diversified in the Old and New Worlds simultaneously through multiple dispersal and vicariance events. The dispersal from East Asia to South America in the middle Oligocene was probably achieved by a long-distance dispersal event. Intensification of aridity and climate cooling events in the late Miocene and Quaternary glacial cycling probably had a significant influence on diversification patterns of the complex. The disjunctions among East Asia, Europe, North America and Africa within Clade IIc are hypothesized to be a result of allopatric speciation. Substrate transitions to Apiaceae probably occurred no earlier than 6 Ma. Biogeographic analyses suggested that the global cooling of the late Eocene, intensification of aridity caused by rapid uplift of the QTP and retreat of the Tethys Sea in the late Miocene, climate cooling events in Quaternary glacial cycling, and substrate transitions have contributed jointly to diversification of the species complex.

Background The reported positive predictive value (PPV) for the “de Winter ECG pattern” to predict an acute left anterior descending artery (LAD) lesion is inconsistent. Besides, the morphology of upsloping or nonupsloping ST depression (STD) may have different significance of severity and prognostication. Methods We searched the MEDLINE database using “de Winter” or “junctional ST‐depression with tall symmetrical T‐waves” or “tall T wave” or “STEMI equivalent” as the item up to March 2020. We compared the ECG differences between the different culprit arteries and various morphological STD. Results A total of 70 patients with analyzable ECGs were included. In 60 patients (LAD group), the LAD was the culprit artery, while in 10 patients (non‐LAD group), there were other etiologies. Maximal STD in V2 or V3 had a PPV of 89% of all patients and 98% of patients without ST elevation in V2 to detect an acute LAD lesion. The presence of q/Q‐wave or poor R‐wave progression in the precordial leads was significantly more often found in patients with upsloping STD than in patients with nonupsloping STD in the LAD group (84% vs. 27%, p

The Pleurotus ostreatus species complex is saprotrophic and of significant economic and ecological importance. However, species delimitation has long been problematic because of phenotypic plasticity and morphological stasis. In addition, the evolutionary history is poorly understood due to limited sampling and insufficient gene fragments employed for phylogenetic analyses. Comprehensive sampling from Asia, Europe, North and South America and Africa was used to run phylogenetic analyses of the P. ostreatus species complex based on 40 nuclear single-copy orthologous genes using maximum likelihood and Bayesian inference analyses. Here, we present a robust phylogeny of the P. ostreatus species complex, fully resolved from the deepest nodes to species level. The P. ostreatus species complex was strongly supported as monophyletic, and 20 phylogenetic species were recognized, with seven putatively new species. Data from our molecular clock analyses suggested that divergence of the genus Pleurotus probably occurred in the late Jurassic, while the most recent common ancestor of the P. ostreatus species complex diversified about 39 Ma in East Asia. Species of the P. ostreatus complex might migrate from the East Asia into North America across the North Atlantic Land Bridge or the Bering Land Bridge at different times during the late Oligocene, late Miocene and late Pliocene, and then diversified in the Old and New Worlds simultaneously through multiple dispersal and vicariance events. The dispersal from East Asia to South America in the middle Oligocene was probably achieved by a long-distance dispersal event. Intensification of aridity and climate cooling events in the late Miocene and Quaternary glacial cycling probably had a significant influence on diversification patterns of the complex. The disjunctions among East Asia, Europe, North America and Africa within Clade IIc are hypothesized to be a result of allopatric speciation. Substrate transitions to Apiaceae probably occurred no earlier than 6 Ma. Biogeographic analyses suggested that the global cooling of the late Eocene, intensification of aridity caused by rapid uplift of the QTP and retreat of the Tethys Sea in the late Miocene, climate cooling events in Quaternary glacial cycling, and substrate transitions have contributed jointly to diversification of the species complex.

Jasmonate ZIM-domain (JAZ) proteins and DELLA proteins are key negative regulators of jasmonates (JAs) and gibberellin (GA) signaling, respectively. In this study, we found JA and GA synergistically promote fiber cell initiation. We characterized the cellular function of a JAZ protein (GhJAZ3), and a DELLA protein (GhSLR1) of cotton (Gossypium hirsutum). GhJAZ3 is specifically expressed in elongating fibers, while GhSLR1 is expressed in different tissues and at a relatively higher level in 3 DPA ovules. GhSLR1 and GhJAZ3 proteins are localized in the cell nucleus. Yeast two-hybrid analysis indicated that GhSLR1, GhJAZ3 and GhDEL65 could interact with each other, and GhSLR1 could also interact with GhBZR1. Overexpression of GhJAZ3 in Arabidopsis increased hypocotyl and root length, leaf trichome length, and plant height, but decreased the number of leaf trichome, while overexpression of GhSLR1 in Arabidopsis decreased hypocotyl length, leaf trichome length and density. Expression of several leaf trichome initiation determinators (GL3, GL2, TTG2 and MYB23) was down-regulated in GhJAZ3 or GhSLR1 transgenic Arabidopsis, while expression of the cell elongation related genes (EXP1, EXP8, EXPL2 and XTH4) was altered in the GhJAZ3 and GhSLR1 transgenic Arabidopsis. Taken together, these results demonstrate that GhJAZ3 and GhSLR1 function in jasmonate and gibberellin mediated epidermal cell differentiation and elongation.

Objective: The objective of this paper was to investigate differential pathways in sporadic amyotrophic lateral sclerosis (SALS) based on pathway network analysis. Materials and Methods: To achieve this goal, first, differentially expressed genes (DEGs) between SALS and normal controls were identified, and a target network was defined as DEGs correlated interactions from the search tool for the retrieval of interacting genes/proteins (STRING). Second, topological centrality analysis was conducted on the target network to identify hub genes and hub network. Third, pathway network was constructed by taking intersections of Reactome database and STRING protein-protein interaction network. Finally, based on extracting the common interactions between target network, hub network and pathway network, we built randomized network, performed randomization test, and denoted differential pathways and hub differential pathways with P < 0.05. Results: There were 485 DEGs and 627 interactions in the target network. The pathway network was comprised 117,370 interactions. What was more, we found that 217 pathways had intersections with the target network. By accessing randomization test and removing the intersected count

TCP proteins are plant-specific transcription factors (TFs), and perform a variety of physiological functions in plant growth and development. In this study, 74 non-redundant TCP genes were identified in upland cotton (Gossypium hirsutum L.) genome. Cotton TCP family can be classified into two classes (class I and class II) that can be further divided into 11 types (groups) based on their motif composition. Quantitative RT-PCR analysis indicated that GhTCPs display different expression patterns in cotton tissues. The majority of these genes are preferentially or specifically expressed in cotton leaves, while some GhTCP genes are highly expressed in initiating fibers and/or elongating fibers of cotton. Yeast two-hybrid results indicated that GhTCPs can interact with each other to form homodimers or heterodimers. In addition, GhTCP14a and GhTCP22 can interact with some transcription factors which are involved in fiber development. These results lay solid foundation for further study on the functions of TCP genes during cotton fiber development.

Plant JAZ (Jasmonate ZIM-domain) proteins play versatile roles in multiple aspects of plant development and defense. However, little is known about the JAZ family in allotetraploid upland cotton (Gossypium hirsutum) so far. In this study, 30 non-redundant JAZ genes were identified in upland cotton through genome-wide screening. Phylogenetic analysis revealed that the 30 proteins in cotton JAZ family are further divided into five groups (I – V), and members in the same group share highly conserved motif structures. Subcellular localization assay demonstrated that GhJAZ proteins are localized in the cell nucleus. Quantitative RT-PCR analysis indicated that GhJAZs display different expression patterns in cotton tissues, and most of them could be induced by Jasmonic (JA). Furthermore, some GhJAZ genes are preferentially expressed in cotton ovules and fibers, and showed differential expression in ovules of wild type cotton and fiberless mutant (fl) during fiber initiation. GhJAZ proteins could interact with each other to form homodimer or heterodimer, and they also interacted with some JA signaling regulators and the proteins involved in cotton fiber initiation. Collectively, our data suggested that some GhJAZ proteins may play important roles in cotton fiber initiation and development by regulating JA signaling as well as some fiber-related proteins.

Litsea elongata (Nees) J. D. Hooker is an economically important timber and medicine tree. In this study, the complete plastid genome of L. elongata was assembled and analyzed. The plastid genome mapped a 154,027 bp circular DNA molecule with a GC content of 39.2%, consisting of a large single-copy region (LSC) of 93,688 bp, a small single-copy region (SSC) of 18,851 bp, and two inverted repeat regions (IRa and Irb) of 20,744 bp. A total of 127 genes were detected in the plastid genome, including eight ribosomal RNA (rRNA) genes, 36 transfer RNA (tRNA) genes, and 83 protein-coding genes. Phylogenomic analysis based on 39 complete plastomes of Laureae in the family Lauraceae supports the close relationships among L. coreana, L. elongata, L. japonica, and L. pierrei.

Fungi of the family Boletaceae are of great importance in both ecology and economy. Our previous molecular phylogenetic studies have shown this family to have an extremely high species diversity in China. To further document the Chinese boletes, morphological studies and phylogenetic analyses were conducted including species of Boletaceae from China and other parts of the world. The results indicate that seven subfamily-level major clades and 62 generic clades can be retrieved, 52 of which are found in China. Furthermore, 100 species (comprising 32 genera) common in China are illustrated and described here in detail. Among them, four genera and 46 species are new to science, and 26 new combinations are proposed. To interpret the species concepts consistently, epitypes for five species are designated based on collections made from or near the type localities. Notes on eight extralimital species are also provided. Among the species reported here, most of the species are known only from East Asia. Only Leccinum scabrum (Bull.) Gray, Porphyrellus porphyrosporus (Fr. & Hok) E.-J. Gilbert and Tylopilus felleus (Bull.) P. Karst. are widely distributed in the Holarctic, and Buchwaldoboletus lignicola (Kallenb.) Pilat; Strobilomyces strobilaceus (Scop.) Berk. are in Eurasia; while Aureoboletus mirabilis (Murrill) Halling, Harrya chromapes (Frost) Halling et al., and Sutorius eximius (Peck) Halling et al. are found throughout East Asia-North America based on morphological and molecular phylogenetic evidences.

Shiraiaceae is an important family in Pleosporales (Dothideomycetes), which includes medical fungi and plant pathogens. Two hypocrellin-producing taxa, Shiraia bambusicola and a novel genus Rubroshiraiagen. nov., typified by Rubroshiraia bambusae are treated in this article. Maximum likelihood analysis, generated via RAxML (GTR+G model), using a combined SSU, LSU, TEF1 and RPB2 sequence dataset, shows that Rubroshiraia is close to Shiraia and belongs to the family Shiraiaceae. Descriptions, illustrations and a taxonomic key are provided for the genera in Shiraiaceae. Rubroshiraia morphologically differs from Shiraia in having small and dark ascostromata and filiform ascospores. Production of the ascostromatal metabolites, hypocrellin A and B, were examined by HPLC and spectrophotometer. The content of hypocrellin A and B of specimen HKAS 102255 (R. bambusae) is twice that produced by HKAS 102253 (S. bambusicola). To clarify the relationship between R. bambusae and Hypocrella bambusae, type material of the latter was examined and provided the illustration.

Hypoxic preconditioning has been shown to improve hypoxic tolerance in mice, accompanied by the downregulation of DNA methyltransferases (DNMTs) in the brain. However, the roles played by DNMTs in the multiple neuroprotective mechanisms associated with hypoxic preconditioning remain poorly understood. This study aimed to establish an in vitro model of hypoxic preconditioning, using a cultured mouse hippocampal neuronal cell line (HT22 cells), to examine the effects of DNMTs on the endogenous neuroprotective mechanisms that occur during hypoxic preconditioning. HT22 cells were divided into a control group, which received no exposure to hypoxia, a hypoxia group, which was exposed to hypoxia once, and a hypoxic preconditioning group, which was exposed to four cycles of hypoxia. To test the ability of hypoxic preadaptation to induce hypoxic tolerance, cell viability was measured using the 3-(4,5-dimethylthiazol-2-yl)-5(3-carboxymethonyphenol)-2-(4-sulfophenyl)-2H-tetrazolium assay. Cell viability improved in the hypoxic preconditioning group compared with that in the hypoxia group. The effects of hypoxic preconditioning on the cell cycle and apoptosis in HT22 cells were examined by western blot assay and flow cytometry. Compared with the hypoxia group, the expression levels of caspase-3 and spectrin, which are markers of early apoptosis and S-phase arrest, respectively, noticeably reduced in the hypoxic preconditioning group. Finally, enzyme-linked immunosorbent assay, real-time polymerase chain reaction, and western blot assay were used to investigate the changes in DNMT expression and activity during hypoxic preconditioning. The results showed that compared with the control group, hypoxic preconditioning downregulated the expression levels of DNMT3A and DNMT3B mRNA and protein in HT22 cells and decreased the activities of total DNMTs and DNMT3B. In conclusion, hypoxic preconditioning may exert anti-hypoxic neuroprotective effects, maintaining HT22 cell viability and inhibiting cell apoptosis. These neuroprotective mechanisms may be associated with the inhibition of DNMT3A and DNMT3B.

Background Bombax ceiba L. (the red silk cotton tree) is a large deciduous tree that is distributed in tropical and sub-tropical Asia as well as northern Australia. It has great economic and ecological importance, with several applications in industry and traditional medicine in many Asian countries. To facilitate further utilization of this plant resource, we present here the draft genome sequence for B. ceiba. Findings We assembled a relatively intact genome of B. ceiba by using PacBio single-molecule sequencing and BioNano optical mapping technologies. The final draft genome is approximately 895 Mb long, with contig and scaffold N50 sizes of 1.0 Mb and 2.06 Mb, respectively. Conclusions The high-quality draft genome assembly of B. ceiba will be a valuable resource enabling further genetic improvement and more effective use of this tree species.

Cinnamomum chago B.S. Sun & H.L. Zhao is an economically important wild woody oil plant of the genus Cinnamomum Trew belonging the family Lauraceae. To better determine its phylogenetic location wi...

A new species, Strobilomyces minor, associated with host plants of Fagaceae, is introduced based on morphological and molecular studies. Strobilomyces minor is characterized by its small basidiomes, light yellowish brown appressed pyramidal scales on the pileus and stipe, large hymenophoral pores, and reticulate basidiospores with large meshes. Maximum Likelihood and Bayesian analyses based on four gene markers (rpb1, rpb2, tef1 and cox3) as well as morphological characters confirmed that this new taxon belongs to Strobilomyces and it is distinct from any known species. A morphological description with line drawings and SEM images for the species is provided.