High Thermoelectric Performance of n-type BiTeSe-Based Composites Incorporated with Both Inorganic and Organic Nanoinclusions.

N-type Bi2Te2.7Se0.3 (BTS) alloy has relatively low thermoelectric performance as compared to its p-type counterpart, which restricts its widespread applications. Herein, we designed and prepared a novel composite system, which consists of an n-type BTS matrix incorporated with both inorganic and organic nanoinclusions. The results indicate that the thermopower of the composite samples can be enhanced by more than 19% upon incorporating inorganic nanophase AgBi3S5 (ABS) due to the energy-dependent carrier scattering, which ensures a high power factor. On the other hand, further incorporation of organic nanophase polypyrrole (PPy) can drastically reduce its lattice thermal conductivity owing to the strong scattering of mid- and low-frequency phonons at these nanoinclusions. As a result, high figures of merit ZTmax = 1.3 at 348 K and ZTave = 1.17 (300-500 K) are achieved with improved mechanical properties in BTS-based composites incorporated with 1.5 wt % ABS and 0.5 wt % PPy, demonstrating that the incorporation of both inorganic and organic nanoinclusions is an effective way to improve its thermoelectric performance.

First Known Human Death After Infection With the Avian Influenza A/H3N8 Virus: Guangdong Province, China, March 2023.

Here, we report on a case of human infection with the H3N8 avian influenza virus. The patient had multiple myeloma and died of severe infection. Genome analysis showed multiple gene mutations and reassortments without mammalian-adaptive mutations. This suggests that avian influenza (A/H3N8) virus infection could be lethal for immunocompromised persons.

Attaining High Figure of Merit in the N-Type Bi2Te2.7Se0.3-Ag2Te Composite System via Comprehensive Regulation of Its Thermoelectric Properties.

n-Type Bi2Te2.7Se0.3 (BTS) is the state-of-the-art thermoelectric material near room temperature. However, the figure of merit ZT of commercial BTS ingots is still limited and further improvement is imperative for their wide applications. Here, the results show that through dispersion of the Ag2Te nanophase in BTS, one can not only elevate its power factor (PF) by as high as 14% (at 300 K) but also reduce its thermal conductivity κtot to as small as ∼29% (at 300 K). Experimental evidences show that the improved PF comes from both increased electron mobility via inhibited Te vacancies and enhanced thermopower due to energy filtering effect, while the reduction of κtot originates from the drop of both electronic thermal conductivity largely owing to the reduced number of vacancy VTe·· and intensified phonon scattering chiefly from the dispersed Ag2Te nanophase. Consequently, the largest ZTmax = 1.31 (at 350 K) and average ZTave = 1.16 (300-500 K) are achieved for the Bi2Te2.7Se0.3-0.3 wt % Ag2Te composite sample, leading to a projected conversion efficiency η = 8.3% (300-500 K). The present results demonstrate that incorporation of nanophase Ag2Te is an effective approach to boosting the thermoelectric performance of BTS.

Simultaneous Enhancement of the Power Factor and Phonon Blocking in Nb-Doped WSe2.

Transition-metal dichalcogenide WSe2 is a potentially good thermoelectric (TE) material due to its high thermopower (S). However, the low electrical conductivity (σ), power factor (PF), and relatively large lattice thermal conductivity (κL) of pristine WSe2 degenerate its TE performance. Here, we show that through proper substitution of Nb for W in WSe2, its PF can be increased by ∼10 times, reaching 5.44 µW cm-1 K-2 (at 850 K); simultaneously, κL lowers from 1.70 to 0.80 W m-1 K-1. Experiments reveal that the increase of PF originates from both increased hole concentration due to the replacement of W4+ by Nb3+ and elevated thermopower (S) caused by the enhanced density of states effective mass, while the reduced κL comes mainly from phonon scattering at point defects NbW. As a result, a record high figure of merit ZTmax ∼0.42 is achieved at 850 K for the doped sample W0.95Nb0.05Se2, which is ∼13 times larger than that of pristine WSe2, demonstrating that Nb doping at the W site is an effective approach to improve the TE performance of WSe2.

Theoretical Study of Intrinsic and Extrinsic Point Defects and Their Effects on Thermoelectric Properties of Cu2SnSe3.

Current understanding of the intrinsic point defects and potential extrinsic dopants in p-type Cu2SnSe3 is limited, which hinders further improvement of its thermoelectric performance. Here, we show that the dominant intrinsic defects in Cu2SnSe3 are CuSn and VCu under different chemical conditions, respectively. The presence of VCu will damage the hole conduction network and reduce hole mobility. Besides, we find that the substitution of Al, Ga, In, Cd, Zn, Fe, and Mn for Sn can inhibit the formation of VCu; introducing CuSn, FeSn, MnSn, and NiCu defects can significantly enhance electronic density of states near the Fermi level due to the contribution of 3d orbitals. Therefore, increasing the Cu content and/or introducing the above beneficial dopants appropriately are expected to cause enhancement of carrier mobility and/or thermopower of Cu2SnSe3. Furthermore, introducing AgCu, AlSn, ZnSn, GeSn, and MnSn defects can induce large mass and strain field fluctuations, lowering lattice thermal conductivity remarkably. Present results not only deepen one's insights into point defects in Cu2SnSe3 but also provide us with a guide to improve its thermoelectric properties.

Levels and Clinical Significance of Regulatory B Cells and T Cells in Acute Myeloid Leukemia.

Acute myeloid leukemia (AML) is a heterogeneous hematological malignancy, whose immunological mechanisms are still partially uncovered. Regulatory B cells (Bregs) and CD4+ regulatory T cells (Tregs) are subgroups of immunoregulatory cells involved in modulating autoimmunity, inflammation, and transplantation reactions. Herein, by studying the number and function of Breg and Treg cell subsets in patients with AML, we explored their potential role in the pathogenesis of AML. Newly diagnosed AML patients, AML patients in complete remission, and healthy controls were enrolled. Flow cytometry was used to detect percentages of Bregs and Tregs. ELISA was conducted to detect IL-10 and TGF-ß in plasma. The mRNA levels of IL-10 and Foxp3 were measured with RT-qPCR. The relationship of Bregs and Tregs with the clinicopathological parameters was analyzed. There was a significant reduction in the frequencies of Bregs and an increase of Tregs in newly diagnosed AML patients compared with healthy controls. Meanwhile, patients in complete remission exhibited levels of Bregs and Tregs comparable to healthy controls. Furthermore, compared with healthy controls and AML patients in complete remission, newly diagnosed AML patients had increased plasma IL-10 but reduced TGF-ß. IL-10 and Foxp3 mRNA levels were upregulated in the newly diagnosed AML patients. However, there were no significant differences in IL-10 and Foxp3 mRNA levels between patients in complete remission and healthy controls. Bregs and Tregs have abnormal distribution in AML patients, suggesting that they might play an important role in regulating immune responses in AML.

Identification and characterization of evolutionarily conserved alternative splicing events in a mangrove genus Sonneratia.

Alternative splicing (AS), which produces multiple mRNA transcripts from a single gene, plays crucial roles in plant growth, development and environmental stress responses. Functional significances of conserved AS events among congeneric species have not been well characterized. In this study, we performed transcriptome sequencing to characterize AS events in four common species of Sonneratia, a mangrove genus excellently adaptive to intertidal zones. 7,248 to 12,623 AS events were identified in approximately 25% to 35% expressed genes in the roots of the four species. The frequency of AS events in Sonneratia was associated with genomic features, including gene expression level and intron/exon number and length. Among the four species, 1,355 evolutionarily conserved AS (ECAS) events were identified from 1,170 genes. Compared with non-ECAS events, ECAS events are of shorter length and less possibility to introduce premature stop codons (PTCs) and frameshifts. Functional annotations of the genes containing ECAS events showed that four of the 26 enriched Gene Ontology (GO) terms are involved in proton transport, signal transduction and carbon metabolism, and 60 genes from another three GO terms are implicated in responses to osmotic, oxidative and heat stresses, which may contribute to the adaptation of Sonneratia species to harsh intertidal environments.

The molecular characteristics of avian influenza viruses (H9N2) derived from air samples in live poultry markets.

OBJECTIVE: To study the molecular characteristics of H9N2-subtype avian influenza viruses (AIVs) isolated from air samples collected in live poultry markets (LPMs) and explore their sequence identities with AIVs that caused human infection. METHODS: Weekly surveillance of H9N2-subtype AIVs in the air of LPMs was conducted from 2015 to 2016. H9-positive samples were isolated from chicken embryos. Whole genome sequences of the isolated AIVs were obtained through high-throughput sequencing. Phylogenetic analysis and key loci variations of the sequences were further analyzed. RESULTS: A total of 327 aerosol samples were collected from LPMs. Nine samples were positive for H9-subtype AIVs based on quantitative real-time reverse transcription polymerase chain reaction (qRRT-PCR). According to the whole genome sequence analysis and phylogenetic analysis, except for the A/Environment/Zhongshan/ZS201505/2015 (ZS201505) strain, 8 gene segments of 8 aerosol H9N2 isolates and 2 H9N2 human isolates in 2015 were located in the same clade. Among key loci variations, except for the ZS201505 strain, H9N2-subtype AIVs had no mutations in eight receptor binding sites of hemagglutinin (HA), and stalks of neuraminidase (NA) proteins exhibited a deletion site of three bases. The PA gene of ZS201503 and ZS201602 exhibited an L336M mutation. The N30D and T215A mutations in the M1 gene and amino acid residues L89V in PB2, P42S in NS1 and S31N in M2 were retained in these 9 strains of H9N2 isolates, which could enhance the virus's virulence. CONCLUSION: Live H9N2 AIVs survived in the aerosol of LPMs in Zhongshan City. The aerosol viruses had a close evolutionary relationship with human epidemic strains, indicating that there might be a risk of AIV transmission from polluted aerosols in LPMs to humans. Mutations in H9N2-subtype AIVs isolated from air samples collected from LPMs suggested their pathogenicity was enhanced to infect humans.

Effects of Pleistocene sea-level fluctuations on mangrove population dynamics: a lesson from Sonneratia alba.

BACKGROUND: A large-scale systematical investigation of the influence of Pleistocene climate oscillation on mangrove population dynamics could enrich our knowledge about the evolutionary history during times of historical climate change, which in turn may provide important information for their conservation. RESULTS: In this study, phylogeography of a mangrove tree Sonneratia alba was studied by sequencing three chloroplast fragments and seven nuclear genes. A low level of genetic diversity at the population level was detected across its range, especially at the range margins, which was mainly attributed to the steep sea-level drop and associated climate fluctuations during the Pleistocene glacial periods. Extremely small effective population size (Ne) was inferred in populations from both eastern and western Malay Peninsula (44 and 396, respectively), mirroring the fragility of mangrove plants and their paucity of robustness against future climate perturbations and human activity. Two major genetic lineages of high divergence were identified in the two mangrove biodiversity centres: the Indo-Malesia and Australasia regions. The estimated splitting time between these two lineages was 3.153 million year ago (MYA), suggesting a role for pre-Pleistocene events in shaping the major diversity patterns of mangrove species. Within the Indo-Malesia region, a subdivision was implicated between the South China Sea (SCS) and the remaining area with a divergence time of 1.874 MYA, corresponding to glacial vicariance when the emerged Sunda Shelf halted genetic exchange between the western and eastern coasts of the Malay Peninsula during Pleistocene sea-level drops. Notably, genetic admixture was observed in populations at the boundary regions, especially in the two populations near the Malacca Strait, indicating secondary contact between divergent lineages during interglacial periods. These interregional genetic exchanges provided ample opportunity for the re-use of standing genetic variation, which could facilitate mangrove establishment and adaptation in new habitats, especially in the context of global climate changes. CONCLUSION: Phylogeogrpahic analysis in this study reveal that Pleistocene sea-level fluctuations had profound influence on population differentiation of the mangrove tree S. alba. Our study highlights the fragility of mangrove plants and offers a guide for the conservation of coastal mangrove communities experiencing ongoing changes in sea-level.

Comparative transcriptome analyses of a mangrove tree Sonneratia caseolaris and its non-mangrove relatives, Trapa bispinosa and Duabanga grandiflora.

Mangroves are a group of unique plants anchoring in and well adapting to the extreme intertidal environment with high salinity, hypoxia and high temperature and ultraviolet (UV) radiation. Sonneratia caseolaris is a major mangrove tree widely distributed across the West-Indo Pacific region, however the genetic mechanisms of its adaptive evolution are still unclear. In the present study, we performed comparative transcriptome analyses between S. caseolaris and its two non-mangrove relatives, Trapa bispinosa and Duabanga grandiflora, to better understand the evolutionary adaptation of S. caseolaris. We obtained 39.92, 69.96 and 47.78 million high-quality paired-end reads using the Illumina platform and de novo assembled them into 47,954, 73,284 and 66,459 unigenes with low redundancy and high coverage. Of them, 20,181, 28,657 and 25,244 unigenes were successfully assigned to level-2 Gene Ontology (GO) terms, and we found the distribution of GO terms were similar among the three species. Approximate 56% unigenes were involved in "response to stimulus" in all three species. Furthermore, we identified 23 unigenes under positive selection in S. caseolaris, which may be crucial for adaptation of this mangrove species to the extreme intertidal environment.

Ancient Geographical Barriers Drive Differentiation among Sonneratia caseolaris Populations and Recent Divergence from S. lanceolata.

Glacial vicariance is thought to influence population dynamics and speciation of many marine organisms. Mangroves, a plant group inhabiting intertidal zones, were also profoundly influenced by Pleistocene glaciations. In this study, we investigated phylogeographic patterns of a widespread mangrove species Sonneratia caseolaris and a narrowly distributed, closely related species S. lanceolata to infer their divergence histories and related it to historical geological events. We sequenced two chloroplast fragments and five nuclear genes for one population of S. lanceolata and 12 populations of S. caseolaris across the Indo-West Pacific (IWP) region to evaluate genetic differentiation and divergence time among them. Phylogenetic analysis based on sequences of nuclear ribosomal internal transcribed spacer and a nuclear gene rpl9 for all Sonneratia species indicate that S. lanceolata individuals are nested within S. caseolaris. We found strong genetic structure among geographic regions (South China Sea, the Indian Ocean, and eastern Australia) inhabited by S. caseolaris. We estimated that divergence between the Indo-Malesia and Australasia populations occurred 4.035 million years ago (MYA), prior to the onset of Pleistocene. BARRIERS analysis suggested that complex geographic features in the IWP region had largely shaped the phylogeographic patterns of S. caseolaris. Furthermore, haplotype analyses provided convincing evidence for secondary contact of the South China Sea and the Indian Ocean lineages at the Indo-Pacific boundary. Demographic history inference under isolation and migration (IM) model detected substantial gene flow from the Sri Lanka populations to the populations in the Java Island. Moreover, multi-locus sequence analysis indicated that S. lanceolata was most closely related to the Indian Ocean populations of S. caseolaris and the divergence time between them was 2.057 MYA, coinciding with the onset of the Pleistocene glaciation. Our results suggest that geographic isolation driven by the Pleistocene ice age resulted in the recent origin of S. lanceolata.

Transcriptome analysis of the Holly mangrove Acanthus ilicifolius and its terrestrial relative, Acanthus leucostachyus, provides insights into adaptation to intertidal zones.

BACKGROUND: Acanthus is a unique genus consisting of both true mangrove and terrestrial species; thus, it represents an ideal system for studying the origin and adaptive evolution of mangrove plants to intertidal environments. However, little is known regarding the two respects of mangrove species in Acanthus. In this study, we sequenced the transcriptomes of the pooled roots and leaves tissues for a mangrove species, Acanthus ilicifolius, and its terrestrial congener, A. leucostachyus, to illustrate the origin of the mangrove species in this genus and their adaptive evolution to harsh habitats. RESULTS: We obtained 73,039 and 69,580 contigs with N50 values of 741 and 1557 bp for A. ilicifolius and A. leucostachyus, respectively. Phylogenetic analyses based on four nuclear segments and three chloroplast fragments revealed that mangroves and terrestrial species in Acanthus fell into different clades, indicating a single origin of the mangrove species in Acanthus. Based on 6634 orthologs, A. ilicifolius and A. leucostachyus were found to be highly divergent, with a peak of synonymous substitution rate (Ks) distribution of 0.145 and an estimated divergence time of approximately 16.8 million years ago (MYA). The transgression in the Early to Middle Miocene may be the major reason for the entry of the mangrove lineage of Acanthus into intertidal environments. Gene ontology (GO) classifications of the full transcriptomes did not show any apparent differences between A. ilicifolius and A. leucostachyus, suggesting the absence of gene components specific to the mangrove transcriptomes. A total of 99 genes in A. ilicifolius were identified with signals of positive selection. Twenty-three of the 99 positively selected genes (PSGs) were found to be involved in salt, heat and ultraviolet stress tolerance, seed germination and embryo development under periodic inundation. These stress-tolerance related PSGs may be crucial for the adaptation of the mangrove species in this genus to stressful marine environments and may contribute to speciation in Acanthus. CONCLUSIONS: We characterized the transcriptomes of one mangrove species of Acanthus, A. ilicifolius, and its terrestrial relative, A. leucostachyus, and provided insights into the origin of the mangrove Acanthus species and their adaptive evolution to abiotic stresses in intertidal environments.

De novo assembly of the transcriptomes of two yellow mangroves, Ceriops tagal and C. zippeliana, and one of their terrestrial relatives, Pellacalyx yunnanensis.

Mangroves are dominant woody plants in the intertidal zones and are of both ecological and economic importance. Species of Ceriops, also called yellow mangroves, have many adaptive traits (including vivipary) for coping with the harsh marine environments. However, little is known about the origination and evolutionary history of this genus. In this study, we aim to provide clues to these two questions by sequencing the transcriptomes of two Ceriops species, Ceriops tagal and Ceriops zippeliana, and one of their terrestrial relatives, Pellacalyx yunnanensis. 48.19, 10.50 and 35.37 million high-quality reads that were generated by Illumina sequencing were assembled into 50,807, 40,543 and 64,147 contigs for the three species, respectively. After removing redundancy and contigs with low coverage, 39,361, 34,362, and 51,668 contigs with the N50 values of 1553, 772 and 1833bp, respectively, were retained for further analysis. Of them, 17,348, 16,484 and 18,038 contigs were successfully annotated with the known gene ontology (GO) terms. GO classifications of the transcriptome profiles for the three species are similar. Most of the contigs were assigned to the cell and organelle related GO terms in the cellular component category, "binding" in the molecular function category, and "cellular process", "metabolic process" and "biological regulation" in the biological process category. We identified more than 6000 pairs of orthologs for each pair of the three species, with the peak of synonymous substitution rate (Ks) distribution of 0.03 between the two Ceriops species and 0.23 between each Ceriops species and P. yunnanensis. Our transcriptomic data provide a great amount of genomic resources for yellow mangroves and can be used for studying the origination and adaptive evolution of mangroves.