A SiC asymmetric cell trench MOSFET with a split gate and integrated p^(+)-poly Si/SiC heterojunction freewheeling diode

A new SiC asymmetric cell trench metal–oxide–semiconductor field effect transistor(MOSFET)with a split gate(SG)and integrated p^(+)-poly Si/SiC heterojunction freewheeling diode(SGHJD-TMOS)is investigated in this article.The SG structure of the SGHJD-TMOS structure can effectively reduce the gate-drain capacitance and reduce the high gateoxide electric field.The integrated p^(+)-poly Si/SiC heterojunction freewheeling diode substantially improves body diode characteristics and reduces switching losses without degrading the static characteristics of the device.Numerical analysis results show that,compared with the conventional asymmetric cell trench MOSFET(CA-TMOS),the high-frequency figure of merit(HF-FOM,R_(on,sp)×Q_(gd,sp))is reduced by 92.5%,and the gate-oxide electric field is reduced by 75%.In addition,the forward conduction voltage drop(V_(F))and gate-drain charge(Q_(gd))are reduced from 2.90 V and 63.5μC/cm^(2) in the CA-TMOS to 1.80 V and 26.1μC/cm^(2) in the SGHJD-TMOS,respectively.Compared with the CA-TMOS,the turn-on loss(E_(on)) and turn-off loss(E_(off)) of the SGHJD-TMOS are reduced by 21.1%and 12.2%,respectively.

依达拉奉对氧诱导视网膜病变乳鼠的作用及其机制研究

目的探讨自由基清除剂依达拉奉对氧诱导视网膜病变乳鼠的抑制作用及可能机制。方法将60只乳鼠根据随机数字表法分为正常对照组、高氧诱导组和药物治疗组,每组20只。高氧诱导复制视网膜病变乳鼠模型,采用黄嘌呤法测定视网膜超氧化物歧化酶(SOD)活力和丙二醛(MDA)含量,苏木精-伊红(HE)染色观察视网膜病理变化,二磷酸腺苷(ADP)染色测定视网膜无灌注区面积,免疫组织化学染色测定视网膜中血管内皮生长因子(VEGF)、CD34的表达。结果3组乳鼠体重在不同时间、不同组间、变化趋势上有差异(P<0.05)。3组乳鼠视网膜SOD、MDA,以及VEGF和CD34光密度值比较,差异有统计学意义(P<0.05);与正常对照组比较,高氧诱导组乳鼠视网膜SOD活力降低(P<0.05),MDA含量升高(P<0.05),VEGF、CD34累积光密度值和平均光密度值升高(P<0.05);与高氧诱导组比较,药物治疗组乳鼠视网膜SOD活力升高(P<0.05),MDA含量降低(P<0.05),VEGF、CD34累积光密度值和平均光密度值降低(P<0.05)。药物治疗组ADP染色无灌注区面积小于高氧诱导组(P<0.05)。HE染色结果显示,正常对照组乳鼠视网膜未见病变;高氧诱导组乳鼠视网膜见大量血管增生、管腔扩张、出血;药物治疗组视网膜病变较高氧诱导组轻,未见出血。结论依达拉奉对氧诱导视网膜病变乳鼠具有保护作用,可抑制视网膜氧化应激反应和新生血管形成。

Long-term costs and benefits analysis of China’s low-carbon policies

China’s long-term,low-emission development goals will hinge on effective low-carbon policies.Therefore,it is valuable to evaluate the costs and benefits of low-carbon policy packages to ensure that low-carbon development concepts and strategies can be well integrated into the policy making process.This work uses the Low-carbon Policy Assessment(LPA)model to assess long-term costs and benefits of climate and energy policies in China under the reference(RS)scenario and the low-carbon(LC)scenario,which includes 25 additional climate and energy policies.In the LC scenario,both energy-related CO2 emissions and total greenhouse gas(GHG)emissions peak around 2030,achieving China’s Nationally Determined Contribution(NDC)target.Of the policies included in the LC scenario,the five with the highest GHG mitigation potential beyond China’s existing policies are:fluorinated gas(F-gas)substitution,a renewable portfolio standard,carbon pricing,carbon capture utilization and storage(CCUS),and a fuel economy standard for heavy duty vehicles(HDVs).In addition to reducing GHG emissions,these policies decrease particulate emissions and associated premature deaths,which would otherwise reduce China’s GDP by nearly 1.5%in 2050.Together,these policies have the potential to promote significant low-carbon prosperity in China.

Immune prognostic implications of PSMD14 and its associated genes signatures in hepatocellular carcinoma

PSMD14 played a vital role in initiation and progression of hepatocellular carcinoma(HCC).However,PSMD14 and its-related genes for the immune prognostic implications of HCC patients have rarely been analyzed.Messenger RNA expression profiles and clinicopathological data were downloaded from The Cancer Genome Atlas(TCGA)and International Cancer Genome Consortium(ICGC)database-Liver Hepatocellular Carcinoma(LIHC).Additionally,we used multi-dimensional bioinformatics analysis to construct and validate a PSMD14-based immune prognostic signature(including RBM45,PSMD1,OLA1,CCT6A,LCAT and IVD)for HCC prognosis prediction.Patients in the high-risk group shown significantly poorer survival than patients in the low-risk group.Calibration curves confirmed the good consistency between the clinical nomogram prediction and the actual observation.Gene set enrichment analyses(GSEA)revealed several significantly enriched pathways,which might help explain the underlying mechanisms.Besides,the rt-PCR further validates the expression of seven immune genes in HCC cells.Our study identified a novel PSMD14-based signature for HCC prognosis prediction,it provided new potential prognostic biomarkers and therapeutic targets for immunotherapy of HCC.

Pathway and policy analysis to China's deep decarbonization

The Paris Agreement marks the beginning of a new era in the global response to climate change, which further clarifies the long-term goal and underlines the urgency addressing climate change. For China,promoting the decoupling between economic growth and carbon emissions as soon as possible is not only the core task of achieving the medium-and long-term goals and strategies to address climate change, but also the inevitable requirement for ensuring the sustainable development of economy and society. Based on the analysis of the historical trends of the economy and social development, as well as society, energy consumption, and key end-use sectors in China, this paper studies the deep carbon emission reduction potential of carbon emission of in energy, industry, building, and transportation and other sectors with "bottom-up" modeling analysis and proposes a medium-and long-term deep decarbonization pathway based on key technologies' mitigation potentials for China. It is found that under deep decarbonization pathway, China will successfully realize the goals set in China's Intended Nationally Determined Contributions of achieving carbon emissions peak around 2030 and lowering carbon dioxide emissions per unit of gross domestic product(GDP) by 60-65% from the 2005 level.From 2030 onward, the development of nonfossil energy will further accelerates, and the share of nonfossil energies in primary energy will amounts to about 44% by 2050. Combined with the acceleration of low-carbon transformation in end-use sectors including industry, building, and transportation, the carbon dioxide emissions in 2050 will fall to the level before 2005, and the carbon dioxide emissions per unit of GDP will decreases by more than 90% from the 2005 level. To ensure the realization of the deep decarbonization pathway, this paper puts forward policy recommendations from four perspectives, including intensifying the total carbon dioxide emissions cap and strengthening the related institutional systems and regulations, improving the incentive policies for industrial lowcarbon development, enhancing the role of the market mechanism, and advocating low-carbon life and consumption patterns.

Early-onset refractory diarrhea due to immune dysregulation, polyendocrinopathy, enteropathy, X-linked syndrome associated with a novel mutation in the FOXP3 gene: A case report

BACKGROUND Immune dysregulation,polyendocrinopthy,enteropathy,X-linked(IPEX)syndrome is a rare X-linked recessive disease caused by mutations in the forkhead box protein 3(FOXP3)gene,which is a master transcriptional regulator for the development and function of CD4+CD25+regulatory T(Treg)cells.The dysfunction of these cells leads to multiple system autoimmune diseases.We present a case of IPEX due to a mutation not reported in the literature before.CASE SUMMARY We report a male patient with IPEX syndrome who presented with refractory diarrhea and malabsorption leading to failure to thrive,as well as with hypothyroidism and nephrotic syndrome.Laboratory investigation showed increased total IgE and Treg cells,decreased free triiodothyronine(FT3)and free thyroxine(FT4),and proteinuria.Multiple dietary and supportive treatments were introduced but did not improve the diarrhea during his hospital stay.Ultimately,whole exome sequencing revealed that the patient was hemizygous for the exon 5,c.542G>A(p.Ser181Asn)mutation of the FOXP3 gene,which has not been previously reported.The patient remains on prednisone and euthyrox while awaiting hematopoietic stem cell transplantation at the time of the compilation of this case report.CONCLUSION We report a novel FOXP3 gene mutation involved in IPEX.A high level of suspicion should be maintained in an early-onset refractory diarrhea patient.

Robust tantalum tuned perovskite oxygen electrode for reversible protonic ceramic electrochemical cells

Perovskite oxides with diverse composition and structure have exhibited grand advances in boosting the oxygen reduction and evolution reaction(ORR/OER),which are essential for the reversible protonic ceramic electrochemical cell(R-PCEC)toward the sustainable hydrogen production and utilization.However,enhancement of their activity and stability remains challenging.Herein,we develop the Ta-regulated BaCo_(0.7)Fe_(0.3)O_(3-δ)perovskite oxygen electrode(Ba(Co_(0.7)Fe_(0.3))_(1-x)Ta_xO_(3-δ))with abundant oxygen defects and achieve the simultaneous enhancement in the electrocatalytic activity and stability toward ORR and OER.As-fabricated R-PCEC with(Ba(Co_(0.7)Fe_(0.3))_(0.9)Ta_(0.1)O_(3-δ))(BCFT10)oxygen electrode performs high power density of 1.47 W·cm^(-2)at 650℃in fuel cell mode,and the current density is up to-2.11 A·cm^(-2)at 1.4 V at 650℃in electrolysis mode,as well as the good stability in both the fuel cell and electrolysis modes.Importantly,the cell also demonstrates a stable cycling operation between fuel cell and electrolysis mode,suggesting a great potential of BCFT10 as oxygen electrode material for R-PCECs.

Hematopoietic aging:Cellular,molecular,and related mechanisms

Aging is accompanied by significant inhibition of hematopoietic and immune system function and disruption of bone marrow structure.Aging-related alterations in the inflammatory response,immunity,and stem cell niches are at the root of hematopoietic aging.Understanding the molecular mechanisms underlying hematopoietic and bone marrow aging can aid the clinical treatment of aging-related diseases.In particular,it is unknown how the niche reprograms hematopoietic stem cells(HSCs)in an age-dependent manner to maintain normal hematopoiesis in elderly individuals.Recently,specific inhibitors and blood exchange methods have been shown to reshape the hematopoietic niche and reverse hematopoietic aging.Here,we present the latest scientific discoveries related to hematopoietic aging and hematopoietic system rejuvenation,discuss the relationships between hematopoietic niche aging and HSC aging,and describe related studies on stem cell-mediated regulation of hematopoietic aging,aiming to provide new ideas for further study.

高活性间充质干细胞干预猕猴卵巢衰老的研究

目的研究一种高活性间充质干细胞(HA-MSCs)对衰老猕猴卵巢结构与功能的干预作用。方法分别使用TeSR-E8培养基和含10%胎牛血清的DMEM/F12培养基从青年猕猴骨髓中分离、扩增得到猕猴HA-MSCs与骨髓间充质干细胞(BMSCs),流式细胞仪检测细胞表面标志物,并进行成脂、成骨和成软骨诱导分化能力鉴定。然后将这2种细胞按1×10^(7)个细胞/kg的剂量,1日1次,连续3 d静脉输注给卵巢衰老猕猴,于治疗前1天、治疗后1、2、3、5个月检测外周血抗苗勒氏管激素(AMH)水平,治疗后第5个月将猕猴安乐死,HE染色观察卵巢的组织病理结构,Masson染色评价卵巢纤维化程度变化,免疫组织化学染色检测卵巢p16、p21衰老相关蛋白的表达水平。两组间比较采用t检验,多组间比较采用单因素方差分析,组间两两比较采用Tukey方法。结果HA-MSCs呈短小梭形,核质比高,形态均一。BMSCs体积较大,呈典型的成纤维细胞形态,有少量杂细胞。HA-MSCs的成脂、成骨和成软骨分化能力均强于BMSCs。与老年模型组比较,HA-MSCs治疗组在治疗后2个月内AMH水平[(1.85±0.21)比(0.29±0.15)ng/mL]增加,该组卵巢组织可见各级卵泡,纤维化程度降低(P均<0.001)。与老年模型组比较,BMSCs治疗组在治疗后1个月时AMH水平[(1.26±0.28)比(0.36±0.16)ng/mL]增加,与HA-MSCs治疗组比较,BMSCs治疗组在治疗后2个月时AMH水平[(1.85±0.21)比(0.60±0.20)ng/mL]降低,该组可见少量未成熟卵泡及原始卵泡,纤维化程度降低(P均<0.001)。老年模型组AMH水平最低,卵巢组织偶见闭锁卵泡,广泛纤维化。卵巢p16、p21蛋白表达水平在老年模型组最高,HA-MSCs治疗组最低,BMSCs治疗组次之。结论HA-MSCs提高衰老卵巢的储备能力,减轻卵巢纤维化,减少卵巢衰老相关蛋白的表达,重启卵泡生成功能,在治疗卵巢衰老上相较BMSCs效果更佳。

Isolation,identification and characterization of an algicidal bacterium from Lake Taihu and preliminary studies on its algicidal compounds

In an effort to identify a bio-agent capable of controlling cyanobacterial blooms, we isolated a bacterial strain, A27, which exhibited strong algicidal activity against the dominant bloom-forming species of Microcystis aeruginosa in Lake Taihu. Based on 16S rRNA gene sequence analysis, this strain belongs to the genus Exiguobacterium. This is the first report of an algicidal bacterial strain belonging to the genus Exiguobacterium. Strain A27 exhibited algicidal activity against a broad range of cyanobacteria, but elicited little or no algicidal activity against the two green algal strains tested. The algicidal activity of strain A27 was shown to be dependent on the density of the bacteria and to have a threshold density of 1.5×106 CFU/mL. Our data also showed that the algicidal activity of strain A27 depended on different growth stages ofMicrocystis aeruginosa （exponential ≈ lag phase 〉 early stationary） rather than that of the bacterium itself. Our results also suggested the algicidal activity of strain A27 occurred via the production of extracellular algicidal compounds. Investigation of the algicidal compounds revealed that there were at least two different algicidal compounds produced by strain A27. These results indicated that strain A27 has great potential for use in the control of outbreaks of cyanobacterial blooms in Lake Taihu.

Synergistic effects of silver nanoparticles and cisplatin in combating inflammation and hyperplasia of airway stents

Anti-inflammatory and antihyperplasia activities are essential requirements for the successful use of airway stents.In this work,silver nanoparticles(AgNPs)and cisplatin(DDP)were combined in a synergistic modification strategy to improve the surface function of airway stents.Using polycaprolactone(PCL)as a drug carrier,a dual-functional PCL-AgNPs-DDP fiber film-coated airway stent was fabricated by electrospinning.The physicochemical and biological properties of the obtained fiber films were examined.The ATR-FTIR,XPS,SEM-EDS and TEM results suggested that AgNPs and DDP could be successfully immobilized onto the airway stent surface.The drug release and surface degradation results revealed that AgNPs and DDP can undergo sustained release from films for 30 d,and the weight loss was approximately 50%after 35 d.In addition,the dual-functional fiber film suppressed human embryonic lung fibroblast growth and exhibited excellent antibacterial activity against Staphylococcus aureus,Pseudomonas aeruginosa and Candida albicans.Furthermore,the effectiveness of the dual-functional fiber film-coated airway stent was evaluated by application to the trachea of New Zealand rabbits.The in vivo results indicated that PCL-AgNPs-DDP fiber film-coated airway stent can significantly inhibit granulation tissue formation and collagen deposition,reduced the expression of IL-8,TNF-α,IL-1α,PCNA,α-SMA and CD68,and ultimately achieved anti-inflammatory and antihyperplasia effects.Hence,this study provides a dual-functional surface-coated airway stent to address the clinical complications associated with respiratory tract inflammation and granulation tissue hyperplasia,thus inhibiting tracheal stenosis.

Sampled-data extended state observer for uncertain nonlinear systems

In this paper, we present a sampled-data nonlinear extended state observer （NLESO） design method for a class of nonlinear systems with uncertainties and discrete time output measurement. To accommodate the inter-sample dynamics, an inter-sample output predictor is employed in the structure of the NLESO to estimate the system output in the sampling intervals, where the prediction is used in the proposed observer instead of the system output. The exponential convergence of the sampled-data NLESO is also discussed and a sufficient condition is given by the Lyapunov method. A numerical example is provided to illustrate the performance of the proposed observer.

Biocompatible and antibacterial soy protein isolate/quaternized chitosan composite sponges for acute upper gastrointestinal hemostasis

Innovative biomedical applications have high requirements for biomedical materials.Herein,a series of biocompatible,antibacterial and hemostatic sponges were successfully fabricated for the treatment of acute upper gastrointestinal bleeding(AUGB).Quaternized chitosan(QC)and soy protein isolate(SPI)were chemically cross-linked to obtain porous SPI/QC sponges(named SQS-n,with n¼30,40,50 or 60 corresponding to the weight percentage of the QC content).The chemical composition,physical properties and biological activity of SQS-n were investigated.SQS-n could support the adhesion and proliferation of L929 cells while triggering no obvious blood toxicity.Meanwhile,SQS-n exhibited good broad-spectrum antibacterial activity against both grampositive bacteria(Staphylococcus aureus)and gram-negative bacteria(Escherichia coli).The in vivo hemostatic effect of SQS-n was evaluated using three different bleeding models.The results revealed that SQS-50 performed best in reducing blood loss and hemostatic time.The overall hemostatic effect of SQS-50 was comparable to that of a commercial gelatin sponge.The enhanced antibacterial and hemostatic activities of SQS-n were mainly attributed to the QC component.In conclusion,this work developed a QC-functionalized hemostatic sponge that is highly desirable for innovative biomedical applications,such as AUGB.