Metal-Oxo Electronic Tuning via In Situ CO Decoration for Promoting Methane Conversion to Oxygenates over Single-Atom Catalysts.

Direct methane conversion (DMC) to oxygenates at low temperature is of great value but remains challenging due to the high energy barrier for C-H bond activation. Here, we report that in situ decoration of Pd1-ZSM-5 single atom catalyst (SAC) by CO molecules significantly promoted the DMC reaction, giving the highest turnover frequency of 207 h-1 ever reported at room temperature and ~100 % oxygenates selectivity with H2O2 as oxidant. Combined characterizations and DFT calculations illustrate that the C-atom of CO prefers to coordinate with Pd1, which donates electrons to the Pd1-O active center (L-Pd1-O, L=CO) generated by H2O2 oxidation. The correspondingly improved electron density over Pd-O pair renders a favorable heterolytic dissociation of C-H bond with low energy barrier of 0.48 eV. Applying CO decoration strategy to M1-ZSM-5 (M=Pd, Rh, Ru, Fe) enables improvement of oxygenates productivity by 3.2-11.3 times, highlighting the generalizability of this method in tuning metal-oxo electronic structure of SACs for efficient DMC process.

Research progress on the catalytic and thermal decomposition of ammonium dinitramide (ADN).

Ammonium dinitramide (NH4N(NO3)2, ADN) is regarded as a promising oxidizer due to its low signature and high specific impulse. Generally, ADN undergoes exothermic decomposition above 140 °C accompanied by the byproduct of ammonium nitrate (AN). The inevitable endothermic decomposition of AN decreases the overall heat release, and so there is a need to develop efficient catalysts to guide ADN decomposition along desired pathways with a lower decomposition temperature and higher heat release. A suitable catalyst should be able to withstand the harsh conditions in a thruster to achieve a stable thrust force, which poses a huge obstacle for manufacturing a stable and active catalyst. This review gives a comprehensive summary of the thermal and catalytic decomposition pathways of ADN for the first time, which is expected to deepen the understanding of its reaction mechanism and provide useful guidance for designing prospective catalysts toward efficient ADN decomposition.

Comprehensive Comparative Analyses of Aspidistra Chloroplast Genomes: Insights into Interspecific Plastid Diversity and Phylogeny.

Limestone karsts are renowned for extremely high species richness and endemism. Aspidistra (Asparagaceae) is among the highly diversified genera distributed in karst areas, making it an ideal group for studying the evolutionary mechanisms of karst plants. The taxonomy and identification of Aspidistra species are mainly based on their specialized and diverse floral structures. Aspidistra plants have inconspicuous flowers, and the similarity in vegetative morphology often leads to difficulties in species discrimination. Chloroplast genomes possess variable genetic information and offer the potential for interspecies identification. However, as yet there is little information about the interspecific diversity and evolution of the plastid genomes of Aspidistra. In this study, we reported chloroplast (cp) genomes of seven Aspidistra species (A. crassifila, A. dolichanthera, A. erecta, A. longgangensis, A. minutiflora, A. nankunshanensis, and A. retusa). These seven highly-conserved plastid genomes all have a typical quartile structure and include a total of 113 unique genes, comprising 79 protein-coding genes, 4 rRNA genes and 30 tRNA genes. Additionally, we conducted a comprehensive comparative analysis of Aspidistra cp genomes. We identified eight divergent hotspot regions (trnC-GCA-petN, trnE-UUC-psbD, accD-psaI, petA-psbJ, rpl20-rps12, rpl36-rps8, ccsA-ndhD and rps15-ycf1) that serve as potential molecular markers. Our newly generated Aspidistra plastomes enrich the resources of plastid genomes of karst plants, and an investigation into the plastome diversity offers novel perspectives on the taxonomy, phylogeny and evolution of Aspidistra species.

A mid- and long-team follow-up study of the application of single-valved bovine pericardium patches in right ventricular outflow tract reconstruction.

Background: Pulmonary regurgitation following right ventricular outflow tract (RVOT) reconstruction may cause right heart dysfunction and even right heart failure. Installation of a single valve at this time point can effectively reduce pulmonary regurgitation, thereby protecting right heart function. Here, we analyzed the outcomes and mid- and long-term follow-up data of patients undergoing single-valved bovine pericardium patch (svBPP) placement for reconstruction and explored the effectiveness and gaps of svBPP in preventing right heart failure. Methods: A retrospective analysis was performed on patients undergoing RVOT reconstruction using BalMonocTM svBPP from October 2010 to August 2020. The follow up procedures included outpatient visits and collection of outcomes. The cardiac ultrasound-related indicators during the follow-up visits included ejection fraction (EF), right ventricular end-diastolic diameter (EDD), pulmonary regurgitation, and pulmonary artery stenosis. The survival rates and reoperation-free rate were analyzed by Kaplan-Meier method. Results: Patients includes tetralogy of Fallot, pulmonary atresia and other complex congenital heart disease. A total of 5 patients (5.7%) died during the perioperative period. Early complications included pleural effusion, cardiac insufficiency, respiratory insufficiency, chylothorax, and atelectasis, all of which were cured. After discharge, 83 patients (94.3%) were effectively followed up. During follow-up, 1 patient died and 1 patient underwent reoperation. The 1-, 5-, and 10-year survival rates were 98.8%, 98.8%, and 98.8%, respectively, and the reintervention-free rates for the same intervals were 98.8%, 98.8%, and 98.8%, respectively. The last follow-up ultrasound revealed severe pulmonary stenosis in 0 cases, moderate stenosis in 2 cases, mild stenosis in 7 cases, and no stenosis in 73 cases. Pulmonary regurgitation was not found in 12 patients; however, there were 2 cases of severe pulmonary regurgitation, 20 cases of moderate pulmonary regurgitation, and 48 cases of mild pulmonary regurgitation. Conclusions: As shown in the mid- and long-term follow-up studies, BalMonocTM svBPP has good performance in RVOT reconstruction. It can effectively eliminate or reduce pulmonary valve regurgitation and protect right heart function. Both réparation à l'Etage ventriculaire (REV) and the modified Barbero-Marcial procedure can bring growth potential and reduce reoperation rate.

Design and research of soft-body cavity-type detonation drivers.

According to the high-energy-density movement characteristics of animals during jumping, soft-body cavity-type detonation driver that combines the explosive chemical reaction mechanism of hydrogen and oxygen is designed, in order to control the robot in jump to achieve output optimization. Then, combined with the theoretical values of the detonation dynamic equation and experimental data for the performance parameters, the influences of the mixing ratio of hydrogen (H2) and oxygen (O2), the volume of mixed hydrogen and oxygen in the cavity, and the shape, wall thickness, and area ratio value of the soft-body cavity on the output performance of the detonation driver are analyzed. When gas volume is 20:10 mL, the jump height reaches 2.5 m. In addition, the upper and lower area ratio of cavity is optimized to 2:1, improving the output performance by 21.6% on average. Therefore, the above research results provide reference for the driver structure design of jumping robot.

Nuclear phylogeny and insights into whole-genome duplications and reproductive development of Solanaceae plants.

Solanaceae, the nightshade family, have ∼2700 species, including the important crops potato and tomato, ornamentals, and medicinal plants. Several sequenced Solanaceae genomes show evidence for whole-genome duplication (WGD), providing an excellent opportunity to investigate WGD and its impacts. Here, we generated 93 transcriptomes/genomes and combined them with 87 public datasets, for a total of 180 Solanaceae species representing all four subfamilies and 14 of 15 tribes. Nearly 1700 nuclear genes from these transcriptomic/genomic datasets were used to reconstruct a highly resolved Solanaceae phylogenetic tree with six major clades. The Solanaceae tree supports four previously recognized subfamilies (Goetzeioideae, Cestroideae, Nicotianoideae, and Solanoideae) and the designation of three other subfamilies (Schizanthoideae, Schwenckioideae, and Petunioideae), with the placement of several previously unassigned genera. We placed a Solanaceae-specific whole-genome triplication (WGT1) at ∼81 million years ago (mya), before the divergence of Schizanthoideae from other Solanaceae subfamilies at ∼73 mya. In addition, we detected two gene duplication bursts (GDBs) supporting proposed WGD events and four other GDBs. An investigation of the evolutionary histories of homologs of carpel and fruit developmental genes in 14 gene (sub)families revealed that 21 gene clades have retained gene duplicates. These were likely generated by the Solanaceae WGT1 and may have promoted fleshy fruit development. This study presents a well-resolved Solanaceae phylogeny and a new perspective on retained gene duplicates and carpel/fruit development, providing an improved understanding of Solanaceae evolution.

Undescribed phloroglucinol derivatives with antiviral activities from Dryopteris atrata (Wall. Ex Kunze) Ching.

Nine undescribed phloroglucinol derivatives (dryatraols A-I) with five different backbones and three known dimeric acylphloroglucinols were isolated from the rhizome of Dryopteris atrata (Wall. Ex Kunze) Ching (Dryopteridaceae). Dryatraol A contains an unprecedented carbon skeleton-a butyrylphloroglucinol and a rulepidanol-type sesquiterpene are linked via a furan ring to form a 6/5/6/6 ring system. Dryatraols B and C are the first examples of monomeric phloroglucinols coupled with the aristolane-type sesquiterpene through the C-C bond. Dryatraol D features a rare spiro [benzofuran-2',5″-furan] backbone. Dryatraols E-I are five undescribed adducts with a butyrylphloroglucinol or filicinic acid incorporated into the germacrene-type sesquiterpene via a pyran ring. These undescribed structures were determined by comprehensively analysing the spectroscopic data, X-ray diffraction results, and electronic circular dichroism calculations. The result of in vitro antiviral activity evaluation indicated that dryatraol C displayed the strongest antiviral effect against both respiratory syncytial virus and influenza A virus (H1N1), with IC50 values of 11.9 µM and 5.5 µM, respectively. Dryatraols F-H exhibited considerable inhibitory activity against herpes simplex virus type 1 (HSV-1), with IC50 values ranging from 2.6 to 6.3 µM. Analysis of the inhibitory mechanism using a time-of-addition assay revealed that dryatraol G may inhibit the replication of HSV-1 by interfering with the late stage of the viral life cycle.

The V-shaped double-layer patch technique for complete atrioventricular septal defect: A novel surgical technique.

OBJECTIVE: Several surgical techniques for repair of a complete atrioventricular septal defect have been developed. However, the postoperative complications with these methods may lead to reoperation during follow-up. The aim of this report is to share our experience with a modified surgical technique for complete atrioventricular septal defect that has anatomic advantages postoperatively and could reduce the reoperation rate. METHODS: Twenty-nine patients who underwent repair of complete atrioventricular septal defect using a V-shaped double-layer patch between April 2011 and September 2019 were retrospectively investigated. RESULTS: There were no deaths (0%) and only 1 reoperation (3.4%) in the series. The aortic crossclamp and cardiopulmonary bypass times were 62.7 ± 16.0 minutes and 113.9 ± 25.9 minutes, respectively. The median follow-up duration was 5.1 years. To date, no significant residual ventricular septal defects have been detected and no left ventricular outflow tract obstruction has been seen on echocardiography in any patient. During follow-up, the left atrioventricular valve status was assessed as no incompetence in 9 patients (31.0%), trivial in 18 patients (62.1%), and mild in 2 patients (6.9%). CONCLUSIONS: The V-shaped double-layer patch technique is a valuable surgical option for patients with complete atrioventricular septal defects. The midterm results in our series document excellent performance of this technique, which augments the area of the anterior valve of the left atrioventricular valve to make it closer to a normal mitral valve and may also reduce the need for reoperation.

PIK-24 Inhibits RSV-Induced Syncytium Formation via Direct Interaction with the p85α Subunit of PI3K.

Phosphoinositide-3 kinase (PI3K) signaling regulates many cellular processes, including cell survival, differentiation, proliferation, cytoskeleton reorganization, and apoptosis. The actin cytoskeleton regulated by PI3K signaling plays an important role in plasma membrane rearrangement. Currently, it is known that respiratory syncytial virus (RSV) infection requires PI3K signaling. However, the regulatory pattern or corresponding molecular mechanism of PI3K signaling on cell-to-cell fusion during syncytium formation remains unclear. This study synthesized a novel PI3K inhibitor PIK-24 designed with PI3K as a target and used it as a molecular probe to investigate the involvement of PI3K signaling in syncytium formation during RSV infection. The results of the antiviral mechanism revealed that syncytium formation required PI3K signaling to activate RHO family GTPases Cdc42, to upregulate the inactive form of cofilin, and to increase the amount of F-actin in cells, thereby causing actin cytoskeleton reorganization and membrane fusion between adjacent cells. PIK-24 treatment significantly abolished the generation of these events by blocking the activation of PI3K signaling. Moreover, PIK-24 had an obvious binding activity with the p85α regulatory subunit of PI3K. The anti-RSV effect similar to PIK-24 was obtained after knockdown of p85α in vitro or knockout of p85α in vivo, suggesting that PIK-24 inhibited RSV infection by targeting PI3K p85α. Most importantly, PIK-24 exerted a potent anti-RSV activity, and its antiviral effect was stronger than that of the classic PI3K inhibitor LY294002, PI-103, and broad-spectrum antiviral drug ribavirin. Thus, PIK-24 has the potential to be developed into a novel anti-RSV agent targeting cellular PI3K signaling. IMPORTANCE PI3K protein has many functions and regulates various cellular processes. As an important regulatory subunit of PI3K, p85α can regulate the activity of PI3K signaling. Therefore, it serves as the key target for virus infection. Indeed, p85α-regulated PI3K signaling facilitates various intracellular plasma membrane rearrangement events by modulating the actin cytoskeleton, which may be critical for RSV-induced syncytium formation. In this study, we show that a novel PI3K inhibitor inhibits RSV-induced PI3K signaling activation and actin cytoskeleton reorganization by targeting the p85α protein, thereby inhibiting syncytium formation and exerting a potent antiviral effect. Respiratory syncytial virus (RSV) is one of the most common respiratory pathogens, causing enormous morbidity, mortality, and economic burden. Currently, no effective antiviral drugs or vaccines exist for RSV infection. This study contributes to understanding the molecular mechanism by which PI3K signaling regulates syncytium formation and provides a leading compound for anti-RSV infection drug development.

Plastomes of limestone karst gesneriad genera Petrocodon and Primulina, and the comparative plastid phylogenomics of Gesneriaceae.

Petrocodon and Primulina are two characteristic genera of Gesneriaceae that exhibit remarkable species and floral diversity, and high endemism across the Sino-Vietnamese Limestone Karsts. To better understand the evolution of limestone gesneriad plastomes, we report nine complete plastomes of seven Primulina and two Petrocodon which have never been assembled before. The newly generated plastomes range from 152,323 to 153,786 bp in size and display a typical quadripartite structure. To further explore the plastome evolution across Gesneriaceae, we assembled five additional plastomes from public reads data and incorporated 38 complete Gesneriaceae plastomes available online into comparative and phylogenomic analyses. The comparison of 52 Gesneriaceae plastomes reveals that not only Primulina and Petrocodon but all gesneriad genera analyzed are highly conserved in genome size, genome structure, gene contents, IR boundary configurations, and codon usage bias. Additionally, sliding window analyses were implemented across alignments of Primulina and Petrocodon for identifying highly variable regions, providing informative markers for future studies. Meanwhile, the SSRs and long repeats of Gesneriaceae plastomes were characterized, serving as useful data in studying population and repetitive sequence evolutions. The results of plastome phylogenetics represent a preliminary but highly resolved maternal backbone genealogy of Primulina and the Old World subtribes of Gesneriaceae.

Biodiversity priority areas and conservation strategies for seed plants in China.

China is known for its abundant plant resources, but biodiversity conservation faces unprecedented challenges. To provide feasible suggestions for sustainable conservation, we used the species richness algorithm and complementary algorithm to study distribution patterns of 34,082 seed plants based on 1,007,196 county-level distribution records. We reconstructed a phylogenetic tree for 95.35% of species and estimated the spatial phylogenetics, followed by correlation analyses between different distribution patterns. We identified 264 counties concentrated in southern and south-western mountainous areas as hotspots which covered 10% of the land area of China and harbored 85.22% of the Chinese seed plant species. The biodiversity conservation priorities we identified were highly representative as we have considered multiple conservation indicators. We evaluated the conservation effectiveness and gaps in the network of nature reserves and identified 31.44, 32.95, and 9.47%, respectively, of the hotspot counties as gaps in the national nature reserves, provincial nature reserves and both together, with respectively 55.77, 61.53, and 28.94% of the species. Analysis of the species composition showed there were a large number of threatened and endemic species occurring in the nature reserves' gaps. The conservation gaps need to be filled by establishing new nature reserves or national parks, especially in south-western China, and more attentions should be paid to strengthen the conservation of specific plant taxa due to the apparent mismatches between different distribution patterns.

Descending aorta translocation for bronchial stenosis caused by shorter interaortic distance.

BACKGROUND AND AIM OF THE STUDY: Numerous anatomic relationships of arteries could cause extrinsic compression of the trachea or bronchus. We report a rare left bronchial stenosis just caused by shorter inter-aortic distance. METHODS: One patient wih recurrent coughing and wheezing was diagnosed as left emphysema.Cardiac computed tomography (CTA) shows a shorter distance between ascending aorta (AAo) and descending aorta (DAo) caused left bronchial stenosis with extrinsic compression of right pulmonary artery. RESULTS: A translocation of the descending aorta was performed in this patient, and postoperative CTA showed that the DAo was translocated to the AAo and the left main bronchial stenosis was relieved. CONCLUSIONS: Translocation of the DAo was necessary for the rare left bronchial stenosis caused by shorter inter-aortic distance and could bring a good outcome.

Ethnobotany of medicinal plants used by the Yao people in Gongcheng County, Guangxi, China.

BACKGROUND: Gongcheng Yao Autonomous County (Gongcheng) is typical for the Yao people in northeastern Guangxi, southern China. The Yao people have a long history of using medicinal plants. In this study, we used ethnobotanical methods to collect traditional knowledge regarding herbal medicines in Gongcheng. Our study provides fundamental data for developing and applying local ethnic medicines and their protection. METHODS: Ethnobotanical data were collected from 103 villages in nine townships from 2014 to 2018 in Gongcheng. A total of 352 informants (279 male and 73 female) were interviewed through semi-structured interviews, key informant interviews, and guided field walks. All the informants were local inhabitants aged between 28 and 101 years of age, of which 40 key informants were selected based on the recommendations of knowledgeable elders and local medical institutions. The informant consensus factor (ICF) was used to evaluate the degree and importance of differences in medicinal plant species and calculated the relative frequencies of citation (RFC) for the recorded medicinal plants. RESULTS: Data from 352 local healers were collected for the study. The Guanyin and Sanjiang townships had the highest distribution of per capita healers (Pch), while the Gongcheng, Lianhua, and Ping'an townships were relatively lower. Of the 352 local healers, more than half were older than 60 years of age and therefore faced the problem of suitable successors and potential loss of traditional medicinal knowledge. There are 12 types of diseases treated by local healers in the study area, and most of the types had a high ICF value. The highest ICF (0.80) was reported for digestive system disease, followed by urinary system disease (0.78) and nervous system disease (0.77). Traumatic injury and orthopedics, digestive system, and rheumatic disease are the most common ailments. The RFC value calculated in 33 medicinal plant species (with an FC of more than 5) ranged from 0.024 to 0.056. The higher RFC values included Kadsura longipedunculata, Schefflera heptaphylla, Plantago asiatica, etc. The most commonly used medicinal method was decoction; plasters, creams, and some form of moxibustion and cupping skills were locally practiced, but only rarely. The local healers used 306 medicinal plant species (116 families and 255 genera). Herbal plants were most commonly used among these, with whole plants and roots being favored. CONCLUSION: The Yao people are highly skilled at using medicinal plants to treat various diseases in Gongcheng. Their treatment methods are varied, convenient, and efficient. Due to the impact of urbanization and economic development, knowledge of traditional medicine is under threat, with declining numbers of local healers and a lack of suitable successors. In order to protect and inherit Yao's traditional medicinal knowledge, it is necessary to educate young healers and to protect biodiversity.

Testing the Club Convergence Dynamics of the COVID-19 Vaccination Rates Across the OECD Countries.

Vaccines are essential to create a more resilient economic growth model. Ending the COVID-19 pandemic requires a more coordinated, effective, and equitable distribution of vaccines across the countries. Therefore, governments are in a race to increase the vaccination rates of the population. Given this backdrop, this paper focuses on the daily vaccinations per million data from March 1, 2021, to October 15, 2021, in 37 Organization for Economic Co-operation and Development (OECD) countries and examines the stochastic properties of the vaccination rates. We adopt the club convergence econometric methodology to investigate the club convergence paths of COVID-19 vaccination rates in OECD regions. The results indicate a significant convergence of the vaccination rates in seven clubs across 30 OECD countries. Moreover, there are seven OECD countries demonstrate non-convergent characteristics, which raises questions about ineffective vaccine balance. In addition, the paper also discusses the potential implications for the post-COVID-19 era.

A dated molecular phylogeny and biogeographical analysis reveals the evolutionary history of the trans-pacifically disjunct tropical tree genus Ormosia (Fabaceae).

The papilionoid legume genus Ormosia (Fabaceae) comprises about 150 species of trees and exhibits a striking disjunct geographical distribution between the New World- and Asian and Australasian wet tropics and subtropics. Modern classifications of Ormosia are not grounded on a well-substantiated phylogenetic hypothesis and have been limited to just portions of the geographical range of the genus. The lack of an evolutionarily-based foundation for systematic studies has hindered taxonomic work on the genus and prevented the testing of biogeographical hypotheses related to the origin of the Old World/New World disjunction and the individual dispersal histories within both areas. Here, we present the most comprehensively sampled molecular phylogeny of Ormosia to date, based on analysis of both nuclear (ITS) and plastid (matK and trnL-F) DNA sequences from 82 species of the genus. Phylogenetically-based divergence times and ancestral range estimations are employed to test hypotheses related to the biogeographical history of the genus. We find strong support for the monophyly of Ormosia and the grouping of all sampled Asian species of the genus into two comparably sized clades, one of which is sister to another large clade containing all sampled New World species. Within the New World clade, additional resolution supports the grouping of most species into three mutually exclusive subordinate clades. The remaining New World species form a fourth well-supported clade in the analyses of plastid sequences, but that result is contradicted by the analysis of ITS. With few exceptions the supported clades have not been previously recognized as taxonomic groups. The biogeographical analysis suggests that Ormosia originated in continental Asia and dispersed to the New World in the Oligocene or early Miocene via long-distance trans-oceanic dispersal. We reject the hypothesis that the inter-hemispheric disjunction in Ormosia resulted from fragmentation of a more continuous "Boreotropical" distribution since the dispersal post-dates Eocene climatic maxima. Both of the Old World clades appear to have originated in mainland Asia and subsequently dispersed into the Malay Archipelago and beyond, at least two lineages dispersing across Wallace's Line as far as the Solomon Islands and northeastern Australia. In the New World, the major clades all originated in Amazonia. Dispersal from Amazonia into peripheral areas in Central America, the Caribbean, and Extra-Amazonian Brazil occurred multiple times over varying time scales, the earliest beginning in the late Miocene. In a few cases, these dispersals were followed by local diversification, but not by reverse migration back to Amazonia. Within each of the two main areas of distribution, multiple modest bouts of oceanic dispersal were required to achieve the modern distributions.

rno-miR-128-3p promotes apoptosis in rat granulosa cells (GCs) induced by norepinephrine through Wilms tumor 1 (WT1).

The mechanism related to ovarian follicular is complex, which has not been fully elucidated. Abundant reports have confirmed that the ovarian function development is closely related to sympathetic innervation. As one of the major neurotransmitters, norepinephrine (NE) is considered an effective regulator of ovarian functions like granulosa cell (GC) apoptosis. However, the mechanism between NE and GC apoptosis in rat is still unclear. In our study, GCs were isolated and cultured in vitro with NE treatment. The apoptosis of GCs was facilitated by NE. Wilms tumor 1 (WT1) was found to be significantly downregulated in GCs after NE treatment, and overexpression of WT1 repressed apoptosis in rat GCs induced by NE. rno-miR-128-3p was found to be significantly enhanced by NE in GCs, and inhibition of rno-miR-128-3p repressed apoptosis in rat GCs induced by NE. Mechanistically, rno-miR-128-3p interacted with WT1 and repressed its expression. In summary, inhibition of rno-miR-128-3p may enhance WT1 expression, and then repress NE-induced apoptosis in rat GCs. Our research may provide a new insight for the improvement of ovarian follicular development.

Genetic diversity and variation of seven Chinese grass shrimp (Palaemonetes sinensis) populations based on the mitochondrial COI gene.

BACKGROUND: Chinese grass shrimp (Palaemonetes sinensis) is an important species widely distributed throughout China, which is ecologically relevant and possesses ornamental and economic value. These organisms have experienced a sharp decline in population due to overfishing. Therefore interest in P. sinensis aquaculture has risen in an effort to alleviate fishing pressure on wild populations. Therefore, we investigated the genetic diversity and variation of P. sinensis to verify the accuracy of previous research results, as well as to assess the risk of diversity decline in wild populations and provide data for artificial breeding. METHODS: Palaemonetes sinensis specimens from seven locations were collected and their genetic variability was assessed based on mitochondrial COI gene segments. DNA sequence polymorphisms for each population were estimated using DNASP 6.12. The demographic history and genetic variation were evaluated using Arlequin 3.11. At last, the pairwise genetic distance (Ds) values and dendrograms were constructed with the MEGA 11 software package. RESULTS: Our study obtained sequences from 325 individuals, and 41 haplotypes were identified among the populations. The haplotype diversity (Hd) and nucleotide diversity (π) indices ranged from 0.244 ± 0.083 to 0.790 ± 0.048 and from 0.0004 ± 0.0001 to 0.0028 ± 0.0006, respectively. Haplotype network analyses identified haplotype Hap_1 as a potential maternal ancestral haplotype for the studied populations. AMOVA results indicated that genetic variations mainly occurred within populations (73.07%). Moreover, according to the maximum variation among groups (FCT), analysis of molecular variance using the optimal two-group scheme indicated that the maximum variation occurred among groups (53.36%). Neutrality and mismatch distribution tests suggested that P. sinensis underwent a recent population expansion. Consistent with the SAMOVA analysis and haplotype network analyses, the Ds and FST between the population pairs indicated that the JN population was distinctive from the others. CONCLUSIONS: Our study conducted a comprehensive characterization of seven wild P. sinensis populations, and our findings elucidated highly significant differences within populations. The JN population was differentiated from the other six populations, as a result of long-term geographical separation. Overall, the present study provided a valuable basis for the management of genetic resources and a better understanding of the ecology and evolution of this species.

Begonia catbensis (sect. Coelocentrum, Begoniaceae), a new species from northern Vietnam.

Begonia catbensis, a new species in Begonia sect. Coelocentrum is described and illustrated. The new species was discovered in lowland limestone hills at Cat Ba National Park and can be easily distinguished from all its congeners by having dendritic hairs on the petiole, adaxial veins and stipules, fimbriate bracts and bracteoles, dense conical bullae on the upper surface of the leaf blade, two tepals in the pistillate flowers and a glabrescent ovary with verrucose wings. Based on IUCN Criteria, the species is currently assessed as "Endangered" (D).

Comparative transcriptome analysis of Chinese grass shrimp (Palaemonetes sinensis) hepatopancreas under ectoparasitic isopod (Tachaea chinensis) infection.

Tachaea chinensis, a parasitic isopod, negatively affects the production of several commercially important shrimp species. To better understand the interaction between shrimp immunity and isopod infection, we performed a transcriptome analysis of the hepatopancreas of Palaemonetes sinensis challenged with T. chinensis. After assembly and annotation, 75,980 high-quality unigenes were obtained using RNA-seq data. Differential gene expression analysis revealed 896 significantly differently expressed genes (DEGs) after infection, with 452 and 444 upregulated and downregulated genes, respectively. Specifically, expression levels of genes involved in detoxification, such as the interferon regulatory factor, venom carboxylesterase-6, serine proteinase inhibitor, and cytochrome P450, were upregulated. Furthermore, expression levels of genes corresponding to retinol dehydrogenase, triosephosphate isomerase, variant ionotropic glutamate receptor, and phosphoenolpyruvate carboxykinase were significantly upregulated after isopod parasitization, indicating that the shrimp's visual system was influenced by isopod parasitization. Moreover, quantitative real-time PCR of 10 DEGs helped validate the RNA-seq findings. These results provide a valuable basis for future studies on the elucidation of immune responses of P. sinensis to T. chinensis infection.