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Quercus section Cyclobalanopsis represents a dominant woody lineage in East Asian evergreen broadleaved forests. Regardless of its ecological and economic importance, little is known about the genomes of species in this unique oak lineage. Quercus glauca is one of the most widespread tree species in the section Cyclobalanopsis. In this study, a high‐quality haplotype‐resolved reference genome was assembled for Q. glauca from PacBio HiFi and Hi‐C reads. The genome size, contig N50, and scaffold N50 measured 902.88, 7.60, and 69.28 Mb, respectively, for haplotype1, and 913.28, 7.20, and 71.53 Mb, respectively, for haplotype2. A total of 37,457 and 38,311 protein‐coding genes were predicted in haplotype1 and haplotype2, respectively. Homologous chromosomes in the Q. glauca genome had excellent gene pair collinearity. The number of R‐genes in Q. glauca was similar to most East Asian oaks but less than oak species from Europe and America. Abundant structural variation in the Q. glauca genome could contribute to environmental stress tolerance in Q. glauca. Sections Cyclobalanopsis and Cerris diverged in the Oligocene, in agreement with fossil records for section Cyclobalanopsis, which document its presence in East Asia since the early Miocene. The demographic dynamics of closely related oak species were largely similar. The high‐quality reference genome provided here for the most widespread species in section Cyclobalanopsis will serve as an essential genomic resource for evolutionary studies of key oak lineages while also supporting studies of interspecific introgression, local adaptation, and speciation in oaks. [ABSTRACT FROM AUTHOR]

Quercus kerrii Craib 1911 (section Cyclobalanopsis) is a widespread tree species in the tropical seasonal forests of southwest China and Northern Indo-China areas. In this study, we sequenced, assembled and annotated the complete chloroplast genome of Q. kerrii. The circular genome was 160,743 bp in length and had a GC content of 36.89%. The Q. kerrii chloroplast genome has a typical quadripartite structure, including two inverted repeat regions (length, 25,825 bp; GC content, 42.76%), a large single-copy region (length, 90,196 bp; GC content, 34.74%), and a small single-copy region (length, 18,897 bp; GC content, 30.60%). Genome annotation has indicated that the Q. kerrii chloroplast genome contained 131 genes, including 86 protein-coding genes, 37 tRNA, and eight rRNA. The phylogenetic tree showed that Q. kerrii had a close relationship with Q. schottkyana Rehder & E.H.Wilson 1916. [ABSTRACT FROM AUTHOR]

Masson pine (Pinus massoniana Lamb.) is an important tree species in China, but its genomic research has been hindered due to a large genome size. Genotyping-by-sequencing (GBS) has been a powerful approach to revolutionize the field of genomic research by facilitating the discovery of thousands of single nucleotide polymorphisms (SNPs) and genotyping in non-model organisms, at relatively low cost. Here, we performed de novo SNP discovery and genotyping in 299 trees via the genotyping-by-sequencing (GBS) approach. The effort produced 9.33 × 109 sequence reads, 265,525 SNP-associated contigs, and 6,739,240 raw SNPs. Further filtering and validation of the SNP-associated contigs for reliable SNPs were performed using blasting against the Pinus tabuliformis reference genome, functional annotation, technical replicates, and custom parameter settings for the optimization. The 159,372 SNP-associated contigs were aligned and validated for SNP prediction, in which 60,038 contigs were searched with hits in the NCBI nr database. We further improved the SNP discovery and genotyping with multiple technical replicates and custom parameter settings filtering. It was found that the use of blasting, annotation, technical replicates, and specific parameter settings removed many unreliable SNPs and identified 20,055 more precise and reliable SNPs from the 10,712 filtered contigs. We further demonstrated the informativeness of the identified SNPs in the inference of some genetic diversity and structure. These findings should be useful to stimulate genomic research and genomics-assisted breeding of Masson pine. [ABSTRACT FROM AUTHOR]

O. elatus Nakai is a traditional medicine that has been confirmed to exert effective antioxidant and anti-inflammatory functions, and is used for the treatment of different disorders. However, its potential beneficial effects on drug induced hepatotoxicity and relevant molecular mechanisms remain unclear. This study investigated the protective effect and further elucidated the mechanisms of action of O. elatus on liver protection. O. elatus chlorogenic acids-enriched fraction (OEB), which included chlorogenic acid and isochlorogenic acid A, were identified by HPLC-MS/MS. OEB was administrated orally daily for seven consecutive days, followed by a single intraperitoneal injection of an overdose of APAP after the final OEB administration. The effects of OEB on immune cells in mice liver were analyzed using flow cytometry. APAP metabolite content in serum was detected using HPLC-MS/MS in order to investigate whether OEB affects CYP450 activities. The intestinal content samples were processed for 16 s microbiota sequencing. Results demonstrated that OEB decreased alanine aminotransferase, aspartate aminotransferase contents, affected the metabolism of APAP, and decreased the concentrates of APAP, APAP-CYS and APAP-NAC by inhibiting CYP2E1 and CYP3A11 activity. Furthermore, OEB pretreatment regulated lipid metabolism by affecting the peroxisome proliferator-activated receptors (PPAR) signaling pathway in mice and also increased the abundance of Akkermansia and Parabacteroides. This study indicated that OEB is a potential drug candidate for treating hepatotoxicity because of its ability to affect drug metabolism and regulate lipid metabolism. [ABSTRACT FROM AUTHOR]

The Oligocene and Miocene are key periods in the formation of the modern topography and flora of East Asian and Indo-China. However, it is unclear how geological and climatic factors contributed to the high endemism and species richness of this region. The Quercus franchetii complex is widespread in the southeast Himalaya fringe and northern Indo-China with a long evolutionary history. It provides a unique proxy for studying the diversity pattern of evergreen woody lineages in this region since the Oligocene. In this study, we combined chloroplast (cp DNA) sequences, nuclear microsatellite loci (nSSRs), and species distribution modeling (SDM) to investigate the impacts of geological events on genetic diversity of the Q. franchetii complex. The results showed that the initial cp DNA haplotype divergence was estimated to occur during the middle Oligocene (30.7 Ma), which might have been raised by the tectonic activity at this episode to the Miocene. The nSSR results revealed two major groups of populations, the central Yunnan-Guizhou plateau (YGP) group and the peripheral distribution group when K = 2, in responding to the rapid YGP uplift during the late Miocene, which restricted gene flow between the populations in core and marginal areas. SDM analysis indicated that the distribution ranges of the Q. franchetii complex expanded northwards after the last glacial maximum, but the core distribution range in YGP was stable. Our results showed that the divergence of Q. franchetii complex is rooted in the mid-Oligocene. The early geological events during the Oligocene, and the late Miocene may play key roles to restrict seed-mediated gene flow among regions, but the pollen-mediated gene flow was less impacted. The uplifts of the YGP and the climate since LGM subsequently boosted the divergence of the populations in core and marginal areas. [ABSTRACT FROM AUTHOR]

Understanding the past and future evolutionary dynamics of dominant species in a forest is important for guiding decisions for biodiversity conservation, forest management, and vegetation restoration. This study used Quercus schottkyana, a dominant tree in subtropical evergreen broad‐leaved forests in southwest China, to investigate the influences of past environmental fluctuations and future changes in climate on the dynamics of tree demographics. Genomic data were obtained for 133 samples of Q. schottkyana from 22 populations using double‐digest genotyping by sequencing. The single‐nucleotide polymorphisms in the genome showed a uniform distribution. Based on principal component analysis and Admixture analysis, two distinct lineages and one mixed group were identified that corresponded to their geographical distribution. Approximate Bayesian computation analyses provided evidence that the divergence among Q. schottkyana populations could be driven by the collision between the Asian and Indian plates during the Miocene, and that climatic fluctuations in the late Pleistocene led to the introgression. The analysis of genotype‐environment relationships showed that annual precipitation and geographic distance were associated with spatial genetic variation. Populations of Q. schottkyana in the northern area of the Jinsha River basin were predicted to be the most vulnerable to future climate change. To increase genetic diversity in the northern Jinsha River basin and to buffer threats from future climate change, managers could use a mixture of local and alien seeds during forest restoration and management. This case study can promote further investigations into assessing how past and future climate change impacts genetic divergence and local adaptation of trees in forests. [ABSTRACT FROM AUTHOR]

In this study, we sequenced the complete chloroplast genome of Quercus schottkyana. The circular genome is 160,746 bp in size, featuring a typical quadripartite structure comprising one large single-copy region (LSC, 90,136 bp), one small single-copy region (SSC, 18,942 bp), and two copies of inverted repeat regions (IRs, 25,834 bp). The genome contains 131 genes, including 86 protein-coding genes, 37 transfer RNA genes, and 8 ribosomal RNA genes. The overall GC content is 36.90%. The maximum likelihood phylogenetic tree reconstructed using IQ-TREE indicated that Q. schottkyana has a closer relationship with Quercus sichourensis and Quercus acuta. [ABSTRACT FROM AUTHOR]

Aiming at the problem of poor reliability of beam membrane fabrication in silicon microstructure processing technology, a technique for preparing microbeams using porous silicon sacrificial layer is proposed. The comparison of different porosity, different depths of porous silicon to beam membrane release and the comparison of different beam structures to beam membrane release were studied. The experiment was carried out by selecting different process parameters and testing the prepared beam membrane. According to the test results, the appropriate electrochemical corrosion process parameters were selected to prepare the porous silicon layer with appropriate porosity, large depth, good support effect and fast release speed, which can realize the release of the beam membrane and improve the reliability of the beam membrane. The field of application of microsensors and microactuators has been greatly increased. [ABSTRACT FROM AUTHOR]

In the present study we selected the endangered species Amygdalus mongolica to investigate the influence of climatic fluctuations on the spatial genetic patterns and evolutionary history of organisms in arid northwest China. The intraspecific genetic variation and demographic history of A. mongolica were investigated using two cpDNA sequences (psb K- psb I and trn L- trn F) from 174 individuals in 15 populations across most of its covered range. Significant genetic differentiation among populations was identified, which resulted from fragmented populations coupled with the enhanced aridification and desertification of the Pleistocene. Twelve haplotypes clustered into two clades, corresponding to the Western region (northernmost Gansu, Hexi Corridor and Alxa Left Banner) and the Eastern region (Urad Houqi, Yinshan Mountains, Urad Zhongqi and Daqing Mountains) respectively. Five independent Pleistocene refugia in different mountainous areas were identified. Amygdalus mongolica has likely experienced westward shifts from refugia along the margins of the Ulanbuhe and Tengger deserts, and also postglacial re-colonisation northward along the Hexi Corridor. A phylogeography study of Amygdalus mongolica in northwest China revealed the influence of complicated paleogeologic and paleoclimatic events upon genetic differentiation and the evolutionary history of this species during the Pleistocene. Significant genetic differentiation among populations was identified. This resulted from fragmented populations coupled with the enhanced aridification and desertification of the Pleistocene. Results of this study have implications for the evolution of other desert plants in northwest China. [ABSTRACT FROM AUTHOR]

Clarifying the relationship between distribution patterns of organisms and geological events is critical to understanding the impact of environmental changes on organismal evolution. Quercus sect. Heterobalanus is now distributed across the Himalaya-Hengduan Mountains ( HHM) and warm lowland in East China, yet how the distribution patterns of this group changed in response to the HHM uplift remains largely unknown. This study examines the effect of tectonic events in the HHM region on the oaks, providing a biological perspective on the geological history of this region. Fifty-six populations of Quercus sect. Heterobalanus were genotyped using four chloroplast DNA regions and nine nuclear simple sequence repeat loci to assess population structure and diversity, supplemented by molecular dating and ancestral area reconstructions. The underlying demographic dynamics were compared using ecological niche models of the species distributions during the last glacial maximum and the present. These analyses illustrate that Quercus sect. Heterobalanus diversified as the HHM uplifted and climatic cooling during the mid-Miocene, colonizing the cold habitats from warm broadleaf mixed forests. Lineages in cold highlands and warm lowlands have diverged as a consequence of local adaptation to diverging climates since the late Miocene. Our results suggest that continuous uplift of the HHM in the late Miocene to early Pliocene accompanied by simultaneous cooling triggered the differentiation of oaks. The biogeography of Quercus sect. Heterobalanus illuminates the geological events responsible for the modern-day HHM. [ABSTRACT FROM AUTHOR]

Quercus franchetii Skan, a crucial indicator plant of dry-hot valley with endemic to southwestern China. In this study, the complete chloroplast genome of Q. franchetii was assembled and characterized. The circular genome was 160,785 bp in length, containing a large single copy (LSC) region of 90,169 bp, a small single copy (SSC) region of 18,828 bp, and a pair of inverted repeat regions of 25,894 bp. Total 131 genes were annotated, comprising 86 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. The phylogenetic analysis indicated that Q. franchetii was closely related to Q. glauca and Q. chungii. [ABSTRACT FROM AUTHOR]

Quercus chungii F.P.Metcalf, a rare oak with endemic to southern China, belongs to the compound trichome base (CTB) lineage in the Cyclobalanopsis section. The complete chloroplast genome of the species was assembled and annotated in this study. The circular genome was 160,731 bp in size, presenting a typical quadripartite structure including one large single-copy region (LSC, 90,140 bp), one small single-copy region (SSC, 18,911 bp), and two copies of inverted repeat regions (IRs, 25,840 bp). It encoded a total of 113 unique genes, including 79 protein-coding genes, 30 tRNA genes, and four rRNA genes. The maximum-likelihood (ML) phylogenetic tree reconstructed by IQ-TREE indicated that Q. chungii was more closely related to Q. myrsinifolia and Q. sichourensis. [ABSTRACT FROM AUTHOR]

Abstract: While the benzazepine SKF83959 elicits classical behavioral responses associated with dopamine D1 receptors, it also acts as a D1 receptor antagonist biochemically. The paradoxical properties of this agent remain an enigma. In the present study, we sought to determine the behavioral effects of SKF83959 in the rat acoustic startle reflex test. Systemic administration of SKF83959 produced a dose-related increase in the startle amplitude with a stimulus of 105dB, and a significant group difference was observed between animals treated with 1mg/kg SKF83959 and vehicle controls. SKF83959 also significantly reduced the latency to startle response to stimuli of 95dB and 105dB in a dose-dependent manner. However, unlike classical dopamine D1-like receptor agonists, SKF83959 failed to disrupt prepulse inhibition (PPI) of either the startle amplitude or the latency to startle response; rather, the agent dose-dependently increased the PPI latency to startle response of 105dB stimulus. These results suggest that the behavioral effects of SKF83959 in the rat acoustic startle reflex paradigm are paradoxical, and these paradoxical effects may be associated with its distinct pharmacological properties. [Copyright &y& Elsevier]

A rapidly changing climate and frequent human activity influences the distribution and community structure of forests. Increasing our knowledge about the genetic diversity and distribution patterns of trees is helpful for forest conservation and management. In this study, nSSRs (nuclear simple sequence repeats) were integrated with a species distribution model (SDM) to investigate the spatial genetic patterns and distribution dynamics of Quercus chungii F.P.Metcalf, a rare oak in the subtropics of southeast China. A total of 188 individuals from 11 populations distributed across the natural range of Q. chungii were genotyped using nine nSSRs. The STRUCTURE analysis indicated that genetic admixture was present in all populations, but the population genetic variation and genetic differentiation were related to their geographical distributions. The SDM result indicated that Q. chungii retreated to the Nanling Mountains and adjacent areas during the Last Glacial Maximum (LGM) period, which corresponds to higher genetic diversity for populations in this region. Landscape genetic analysis showed that the Nanling Mountains served as a corridor for organism dispersal at the glacial and interglacial periods within the Quaternary. Based on these results, we propose that establishing nature reserves to protect the ecological corridor across the Nanling Mountains is necessary for the conservation of regional species genetic diversity, as well as the ecosystem of evergreen broadleaved forests in southern China. The study combines species distribution models and genetic diversity to provide new insight into biodiversity conservation and forest management under future climate change. [ABSTRACT FROM AUTHOR]

Paraquat (PQ), a broad‐spectrum agricultural pesticide, causes cellular toxicity by increasing oxidative stress levels in various biological systems, including the reproductive system. PQ exposure causes embryotoxicity and reduces the developmental abilities of embryos. However, there is little information regarding the toxic effects of PQ on oocyte maturation. In this study, we studied the toxic effects of PQ exposure and the effects of melatonin on PQ‐induced damage in bovine oocytes. PQ exposure disrupted nuclear and cytoplasmic maturation, which was manifested as decreased cumulus cell expansion, reduced first polar body extrusion, and abnormal distribution patterns of cortical granules and mitochondria. In addition, PQ treatment severely disrupted the ability of the resulted in vitro‐produced embryos to develop to the blastocyst stage. Moreover, PQ exposure significantly increased the intracellular reactive oxygen species (ROS) level and early apoptotic rate, and decreased the glutathione (GSH) level, antioxidative CAT and GPx4 mRNA, and apoptotic‐related Bcl-2/Bax mRNA ratio. These results indicated that PQ causes reproductive toxicity in bovine oocytes. Melatonin application resulted in significant protection against the toxic effects of PQ in PQ‐exposed oocytes. The mechanisms underlying the role of melatonin included the inhibition of PQ‐induced p38 mitogen‐activated protein kinase (MAPK) activation, and restoration of abnormal trimethyl‐histone H3 lysine 4 (H3K4me3) and trimethyl‐histone H3 lysine 9 (H3K9me3) levels. These results reveal that melatonin serves as a powerful agent against experimental PQ‐induced toxicity during bovine oocyte maturation and could form a basis for further studies to develop therapeutic strategies against PQ poisoning. [ABSTRACT FROM AUTHOR]

Bactrocera correcta is one of the most destructive pests of horticultural crops in tropical and subtropical regions. Despite the economic risk, the population genetics of this pest have remained relatively unexplored. This study explores population genetic structure and contemporary gene flow in B. correcta in Chinese Yunnan Province and attempts to place observed patterns within the broader geographical context of the species' total range. Based on combined data from mtDNA cox1 sequences and 12 microsatellite loci obtained from 793 individuals located in 7 countries, overall genetic structuring was low. The expansion history of this species, including likely human-mediated dispersal, may have played a role in shaping the observed weak structure. The study suggested a close relationship between Yunnan Province and adjacent countries, with evidence for Western and/or Southern Yunnan as the invasive origin of B. correcta within Yunnan Province. The information gleaned from this analysis of gene flow and population structure has broad implications for quarantine, trade and management of this pest, especially in China where it is expanding northward. Future studies should concentrate effort on sampling South Asian populations, which would enable better inferences of the ancestral location of B. correcta and its invasion history into and throughout Asia. [ABSTRACT FROM AUTHOR]

Janus TiPX (X = F, Cl, and Br) monolayers were systematically investigated through first-principles calculations. The Janus TiPX monolayers exhibit mechanical and dynamic stability. Two monolayers are indirect bandgap semiconductors, except the TiPBr monolayer, which has the features of a quasi-direct bandgap semiconductor. Biaxial strain can modify the band gap of single layers. The Janus TiPX monolayers have remarkable flexibility and piezoelectric properties. In particular, the TiPF monolayer shows high horizontal (44.18 pm V -1 ) and vertical piezoelectric coefficients (-3.59 pm V -1 ). These values exceed those of conventional bulk materials, like GaN (3.1 pm V -1 ) and α-quartz (2.3 pm V -1 ). All of the monolayers have absorption coefficients of 10 5 cm -1 for visible and ultraviolet (UV) light, which are one order of magnitude greater than that of MoSSe. Furthermore, TiPX monolayers have high carrier mobility. Janus TiPX monolayers represent a class of two-dimensional (2D) materials with exceptional properties and multifunctionality, holding significant promise for various applications in piezoelectric sensors, solar cells, and nano-electronic devices.