Clinical Study of Mesenchymal Stem Cell Treatment for Acute Respiratory Distress Syndrome Induced by Epidemic Influenza A(H7N9) Infection: A Hint for COVID-19 Treatment

2013年,H7N9病毒在哺乳动物宿主之间迅速传播,并具有人与人之间传播的风险。患者表现为重症肺炎、急性呼吸窘迫综合征(acute respiratory distress syndrome,ARDS)和呼吸衰竭。间充质干细胞(mesenchymal stem cell,MSC)移植在病毒性肺炎的治疗中有广阔的前景,并于2013年作为应急性治疗方法来治疗H7N9感染的ARDS。该研究在单中心开展,为开放式临床研究。根据自愿和知情同意的原则,17例H7N9感染的ARDS患者移植同种异体经血来源的MSC作为治疗组,44例H7N9感染的ARDS患者作为对照组。与对照组相比,MSC移植显著降低了ARDS病死率(MSC治疗组和对照组死亡率分别为17.6%和54.5%)。此外,在对4名MSC移植患者进行为期5年的随访中,未发现MSC移植产生有害影响。总体而言,该研究结果表明MSC移植显著提高了H7N9感染的ARDS的存活率,并为开展临床前和临床应用MSC治疗H7N9感染的ARDS的研究提供了理论基础。由于H7N9和新型冠状病毒肺炎(coronavirus disease 2019,COVID-19)临床表现相似(如ARDS和呼吸衰竭),并继发多器官功能障碍,因此基于MSC的疗法可能为COVID-19所致的ARDS患者获益。

MOF-Transformed In_(2)O_(3-x)@C Nanocorn Electrocatalyst for Efficient CO_(2)Reduction to HCOOH

For electrochemical CO_(2) reduction to HCOOH,an ongoing challenge is to design energy efficient electrocatalysts that can deliver a high HCOOH current density(JHCOOH)at a low overpotential.Indium oxide is good HCOOH production catalyst but with low con-ductivity.In this work,we report a unique corn design of In_(2)O_(3-x)@C nanocatalyst,wherein In_(2)O_(3-x)nanocube as the fine grains dispersed uniformly on the carbon nanorod cob,resulting in the enhanced conductivity.Excellent performance is achieved with 84%Faradaic efficiency(FE)and 11 mA cm^(−2)JHCOOH at a low potential of−0.4 V versus RHE.At the current density of 100 mA cm^(−2),the applied potential remained stable for more than 120 h with the FE above 90%.Density functional theory calculations reveal that the abundant oxygen vacancy in In_(2)O_(3-x) has exposed more In^(3+) sites with activated electroactivity,which facilitates the formation of HCOO*intermediate.Operando X-ray absorp-tion spectroscopy also confirms In^(3+) as the active site and the key intermediate of HCOO*during the process of CO_(2) reduction to HCOOH.

Detection of oil spill based on CBF-CNN using HY-1C CZI multispectral images

Accurate detection of an oil spill is of great significance for rapid response to oil spill accidents.Multispectral images have the advantages of high spatial resolution,short revisit period,and wide imaging width,which is suitable for large-scale oil spill monitoring.However,in wide remote sensing images,the number of oil spill samples is generally far less than that of seawater samples.Moreover,the sea surface state tends to be heterogeneous over a large area,which makes the identification of oil spills more difficult because of various sea conditions and sunglint.To address this problem,we used the F-Score as a measure of the distance between forecast value and true value,proposed the Class-Balanced F loss function(CBF loss function)that comprehensively considers the precision and recall,and rebalances the loss according to the actual sample numbers of various classes.Using the CBF loss function,we constructed convolution neural networks(CBF-CNN)for oil spill detection.Based on the image acquired by the Coastal Zone Imager(CZI)of the Haiyang-1C(HY-1C)satellite in the Andaman Sea(study area 1),we carried out parameter adjustment experiments.In contrast to experiments of different loss functions,the F1-Score of the detection result of oil emulsions is 0.87,which is 0.03–0.07 higher than cross-entropy,hinge,and focal loss functions,and the F1-Score of the detection result of oil slicks is 0.94,which is 0.01–0.09 higher than those three loss functions.In comparison with the experiment of different methods,the F1-Score of CBF-CNN for the detection result of oil emulsions is 0.05–0.12 higher than that of the deep neural networks,supports vector machine and random forests models,and the F1-Score of the detection result of oil slicks is 0.15–0.22 higher than that of the three methods.To verify the applicability of the CBF-CNN model in different observation scenes,we used the image obtained by HY-1C CZI in the Karimata Strait to carry out experiments,which include two studies areas(study area 2 and study area 3).The experimental results show that the F1-Score of CBF-CNN for the detection result of oil emulsions is 0.88,which is 0.16–0.24 higher than that of other methods,and the F1-Score of the detection result of oil slicks is 0.96–0.97,which is 0.06–0.23 higher than that of other methods.Based on all the above experiments,we come to the conclusions that the CBF loss function can restrain the influence of oil spill and seawater sample imbalance on oil spill detection of CNN model thus improving the detection accuracy of oil spills,and our CBF-CNN model is suitable for the detection of oil spills in an area with weak sunglint and can be applied to different scenarios of CZI images.

How can the Dual-atom Catalyst FeCo-NC Surpass Singleatom Catalysts Fe-NC/Co-NC in CO_(2) RR?-CO Intermediate Assisted Promotion via a Synergistic Effect

Atomically dispersed catalysts are widely adopted in CO_(2)reduction reaction(CO_(2)RR)due to maximal atomic utilization and high catalytic activity.Dual-atom catalysts(DACs),with more dispersed active sites and distinct electronic structures compared with single-atom catalysts(SACs),may exhibit diverse catalytic performance.Herein,the DAC FeCo-NC and SAC Fe-NC/Co-NC are employed as probes to explore DACs advantage in CO_(2)RR.Results show that the moderate interaction between the dual-atom center and N coordination balances structural stability and catalytic activity.CO is the only product on Fe-NC/Co-NC,and the high limiting potentials from−1.22 to−1.67 V inhibit further reduction.FeCo-NC assisted with CO intermediate exhibits low limiting potentials of−0.64 V for both CH_(3)OH and CH 4,comparable to those on Cu-based catalysts.Under circumstance of applied potentials,CO_(2)RR on FeCo-NC has greater advantages in yielding CH_(3)OH and CH 4 than that on Fe-NC/Co-NC,and hydrogen evolution reaction is severely inhibited.The intrinsic essence is that dual-atom center can provide large spin-polarization and multi-electron transfer capability,rendering CO intermediates as effective electronic and geometric modifiers in CO_(2)RR.This work highlights FeCo-NC as a high-performance CO_(2)RR catalyst toward deep-reduction C1 products and elucidates CO intermediate assisted promotion mechanism via a dual-atom synergistic effect.

Construction of pH-universal hydrogen evolution freeway in MoO_(3)-MoNi_(4)@Cu core-shell nanowires via synergetic electronic and geometric effect

Both the adsorption/dissociation of water molecules and hydrogen intermediate(H*)are the major limitations to hydrogen evolution reaction(HER).Herein,the modulation of electronic structure and geometric configuration are combined to design onedimensional electrocatalyst with outstanding HER activity in a wide pH range.The catalyst was composed of molybdenum trioxide doped molybdenum nickel alloy supported by copper nanowires(MoO_(3)-MoNi_(4)@Cu NWs).As revealed by the experimental characterizations and theoretical calculations,Cu NWs act as the electron donator to MoNi4,resulting in up shift of the d-band center in MoNi4,thus expediting H_(2)O adsorption and dissociation.Moreover,the introduction of amorphous MoO_(3) sets up a unique geometric configuration on MoNi4 for the accelerated H*transfer via hydrogen-bond and hydrogen spillover.This work provides a synergetic route for constructing HER freeway and promotes further investigations on more versatile electrocatalysis involving H_(2)O or H*.

Exosomes loaded a smart bilayer-hydrogel scaffold with ROS-scavenging and macrophage-reprogramming properties for repairing cartilage defect

Enhancing the regeneration of cartilage defects remains challenging owing to limited innate self-healing as well as acute inflammation arising from the overexpression of reactive oxygen species(ROS)in post-traumatic microenvironments.Recently,stem cell-derived exosomes(Exos)have been developed as potential cell-free therapy for cartilage regeneration.Although this approach promotes chondrogenesis,it neglects the emerging inflammatory microenvironment.In this study,a smart bilayer-hydrogel dual-loaded with sodium diclofenac(DC),an anti-inflammatory drug,and Exos from bone marrow-derived mesenchymal stem cells was developed to mitigate initial-stage inflammation and promote late-stage stem-cell recruitment and chondrogenic differentiation.First,the upper-hydrogel composed of phenylboronic-acid-crosslinked polyvinyl alcohol degrades in response to elevated levels of ROS to release DC,which mitigates oxidative stress,thus reprogramming macrophages to the pro-healing state.Subsequently,Exos are slowly released from the lower-hydrogel composed of hyaluronic acid into an optimal microenvironment for the stimulation of chondrogenesis.Both in vitro and in vivo assays confirmed that the dual-loaded bilayer-hydrogel reduced post-traumatic inflammation and enhanced cartilage regeneration by effectively scavenging ROS and reprogramming macrophages.The proposed platform provides multi-staged therapy,which allows for the optimal harnessing of Exos as a therapeutic for cartilage regeneration.

ZIKA virus isolated from mosquitoes:a field and laboratory investigation in China,2016

A field investigation of arboviruses was conducted in Dejiang, Guizhou Province in the summer of 2016. A total of 8,795 mosquitoes, belonging to four species of three genera, and 1,300 midges were collected. The mosquito samples were identified on site according to their morphology, and the pooled samples were ground and centrifuged in the laboratory. The supernatant was incubated with mosquito tissue culture cells(C6/36) and mammalian cells(BHK-21) for virus isolation. The results indicated that 40%(3,540/8,795) were Anopheles sinensis, 30%(2,700/8,795) were Culex pipiens quinquefasciatus, and 29%(2,530/8,795)were Armigeres subbalbeatus. Furthermore, a total of eight virus isolates were obtained, and genome sequencing revealed two Zika viruses(ZIKVs) isolated from Culex pipiens quinquefasciatus and Armigeres subbalbeatus, respectively; three Japanese encephalitis viruses(JEVs) isolated from Culex pipiens quinquefasciatus; two Banna viruses(BAVs) isolated from Culex pipiens quinquefasciatus and Anopheles sinensis, respectively; and one densovirus(DNV) isolated from Culex pipiens quinquefasciatus.The ZIKVs isolated from the Culex pipiens quinquefasciatus and Armigeres subbalbeatus mosquitoes represent the first ZIKV isolates in China's Mainland. This discovery presents new challenges for the prevention and control of ZIKV in China, and prompts international cooperation on this global issue.

Genome sequencing and phylogenetic analysis of Banna virus(genus Seadornavirus,family Reoviridae)isolated from Culicoides

In an investigation of blood-sucking insects and arboviruses, a virus(YN12243) was isolated from Culicoides samples collected in the Sino-Burmese border region of Yunnan Province, China. The virus caused cytopathic effect(CPE) in C6/36 cells and passaged stably. Polyacrylamide gel analysis showed that the genome of YN12243 was composed of 12 segments of double-stranded RNA(dsRNA), with a distribution pattern of 6-6. The nucleotide and amino acid sequences of the coding region(1.12 segments) were17,803 bp and 5,925 amino acids in length, respectively. The phylogenetic analysis of VP1 protein(RdRp) revealed that YN12243 belonged to genus Seadornavirus of family Reoviridae, and further analysis indicated that YN12243 belongs to the Banna virus(BAV) genotype A2. Additionally, YN12243 was located in the same evolutionary cluster as BAV strains isolated from different mosquito species, suggesting that the BAV isolated from Culicoides does not have species barriers. These results indicate that Culicoides can also be a vector for BAV. In view of the hematophagous habits of Culicoides on cattle, horses, deer, and other large animals, as well as the possibility of spreading and causing a variety of animal arboviral diseases, it is important to improve infection detection and monitor the BAV in large livestock.

Re-isolation of Wuxiang Virus from Wild Sandflies Collected from Yangquan County, China

We previously isolated a new species of the genus Phlebovirus from wild sandflies collected from Wuxiang County in central China,which named the Wuxiang virus(WUXV).In this study,we re-isolated the WUXV from wild sandflies collected from two villages in Yangquan County,China in 2019.Four virus isolates that caused cytopathic effects in BHK-21 cells were successfully isolated from sandfly specimens collected from chicken pens and sheep pens.Phylogenetic analyses of the L,M and S gene segments of the viruses revealed that the four virus strains represented the previously isolated WUXV.The minimum infection rate(MIR)of the virus isolated from the sheep pen was 3.21,and the MIR of the virus isolated from the chicken pen was 3.45.The positive rates of Wuxiang virus neutralizing antibodies in serum samples of local healthy people and domestic chickens were 8.7%(4/46)and 100%(4/4),respectively,suggesting that Wuxiang virus can infect human and animal.In view of the fact that Wuxiang virus is infectious to humans and animals and has a relatively wide geographical distribution in China,it is of great public health significance to strengthen the investigation and study on the infection status of Wuxiang virus in humans and animals.

Emergence of Zika Virus in Culex tritaeniorhynchus and Anopheles sinensis Mosquitoes in China

Zika virus(ZIKV)has been isolated from mosquitoes such as Aedes,Mansonia uniformis,and Culex perfuscus;However,the isolation of ZIKV from Anopheles sinensis and Culex tritaeniorhynchus has not yet been reported.In June and July2018,22,985 mosquitoes and 57,500 midges were collected in Jiangxi Province in southeastern China.Among them,six strains of ZIKV were isolated from mosquitoes:four from An.sinensis and two from Cx.tritaeniorhynchus.Molecular genetic analysis showed that the ZIKV isolated from An.sinensis and Cx.tritaeniorhynchus belonged to genotype 2 in the Asian evolutionary branch of ZIKV.In addition,the ZIKV strains isolated from An.sinensis and Cx.tritaeniorhynchus had amino acid substitutions identical to ZIKV strains prevalent in South America since 2015.This study is the first to isolate ZIKV from mosquito specimens collected in the wild of Jiangxi Province,China;This is also the first time that ZIKV has been isolated from An.sinensis and Cx.tritaeniorhynchus.Given that An.sinensis and Cx.tritaeniorhynchus have a very wide geographical distribution in China and even in eastern and southern Asia,the isolation of several strains of ZIKV from these two mosquitoes poses new challenges for the prevention and control of ZIKV infection in the mainland of China and countries and regions with the same distribution of mosquitoes.

Enabling kinetically fast activation of carbon nanotube@nickel selenide through pore-phase dual regulation in aqueous zinc battery

Metal chalcogenide compounds can be used as high-performance cathodes for aqueous Zn batteries.However,the low accessible surfaces and violent volumetric expansion limit their properties and applications.To address these,phase-engineering strategies coupled with a hollow structure were applied to regulate the adsorption/desorption of OH−on the electrode surface and enhance the electrochemical performance.In this study,using a Se@C nanorod template,a series of carbon nanotube(CNT)-supported nickel selenides,including cubic NiSe_(2),NiSe_(2)/Ni_(0.85)Se composites,and hexagonal Ni_(0.85)Se,were synthesized through an in situ selenylation process for the first time.Due to the large specific surface,high porosity,and hollow carbon skeleton,the optimized NiSe_(2)/Ni_(0.85)Se/CNT has a high specific capacity of 616 Cg^(−1),excellent rate capability,and stable cycling performance.In addition,its inside Faradic mechanism was investigated using a series of ex situ characterizations and density functional theory calculations.Thus,the fabricated Ni//Zn battery presents a high energy density of 311.4 W h kg^(−1) at 3485 W kg^(−1) and long cycling life.This study offers an ingenious strategy for designing nickel selenide electrodes and deeper perception for its Faradic mechanism in alkaline Zn battery.

The impact of Typhoon Lekima (2019) on East China: a postevent survey in Wenzhou City and Taizhou City

Typhoon Lekima(2019)struck Zhejiang Province on 10 August 2019 as a supertyphoon,which severely impacted Zhejiang Province.The typhoon killed 45 people and left three others missing,and the total economic loss reached 40.71 billion yuan.This paper reports a postdisaster survey that focuses on the storm precipitation,flooding,landslides,and weather services associated with Typhoon Lekima(2019)along the southeastern coastline of Zhejiang Province.The survey was conducted by a joint survey team from the Shanghai Typhoon Institute and local meteorological bureaus from 26 to 28 August,2019,approximately two weeks after the disaster.Based on this survey and subsequent analyses of the results,we hope to develop countermeasures to prevent future tragedies.

Phosphorus-doped iron-nitrogen-carbon catalyst with pentacoordinated single atom sites for efficient oxygen reduction

Single-atomic Fe-N4 is the well-acknowledged active site in iron-nitrogen-carbon(Fe-N-C)material for oxygen reduction reaction(ORR).The adjusting of the electronic distribution of Fe-N4 is promising for further enhancing the performance of the Fe-N-C catalyst.Herein,a phosphorus(P)-doped Fe-N-C catalyst with penta-coordinated single atom sites(FeNPC)is reported for efficient oxygen reduction.Fe K-edge X-ray absorption spectroscopy(XAS)verifies the coordination environment of single Fe atom,while density functional theory(DFT)calculations reveal that the penta-coordination and neighboring doped P atoms can simultaneously change the electronic distribution of Fe-N_(4)and its adsorption strength of key intermediates,reducing the reactionfree energy of the potential-limiting step.Electrochemical tests validate the remarkable intrinsic ORR activity of FeNPC in alkaline media(a half-wave potential(E_(1/2))of 0.904 V vs.reversible hydrogen electrode(RHE)and limited current density(JL)of 6.23 mA·cm^(−2))and an enhanced ORR performance in neutral(E_(1/2)=0.751 V,J_(L)=5.27 mA·cm^(−2))and acidic media(E_(1/2)=0.735 V,JL=5.82 mA·cm^(−2))with excellent stability,highlighting the benefits of optimizing the local environment of singleatomic Fe-N4.

Selectivity switching between CO and formate for CO_(2) reduction on Sb modified amorphous ZnO by electronic effect

The adjustable intermediate binding capacity in electrocatalytic carbon dioxide(CO_(2))reduction is critical for varying the reaction pathways to desired products.Herein,we first report the synthesis of boron-doped amorphous zinc oxide with(B-a-ZnO-Sb)or without antimony nanoparticles embedding(B-a-ZnO)via one-step wet chemical method,which is easy to scale up by enlarging the vessel and increasing feeding.Sb successfully realizes the product switching from CO on B-a-ZnO to formate on B-a-ZnOSb.Both experimental and theoretical results reveal that Sb weakens the charge interaction on Zn atoms.Based on the moderate adsorption of*COOH and strong adsorption of*OCHO and*HCOOH for B-a-ZnO,the foreign Sb weakens the adsorption of these intermediates and brings about a favor formate production instead of CO.This work points out a new direction for the synthesis of amorphous ZnO-based catalysts and provides advanced insights into the aimed selectivity switch for CO_(2)reduction by electronic effect.

Ultrahigh Hydrogen Uptake in an Interpenetrated Zn_(4)O-Based Metal–Organic Framework

As a highly promising candidate for hydrogen storage,crucial to vehicles powered by fuel cells,metal–organic frameworks(MOFs)have attracted the attention of chemists in recent decades.H_(2) uptake in an MOF is influenced by many factors such as pore size,ligand functionalization,and open metal sites.The synergistic effect of these factors can significantly enhance the H_(2) uptake in an MOF.Herein,we report a twofold interpenetrated MOF(UPC-501)based on a Zn_(4)O(COO)_(6)secondary building unit with the H_(2) uptake of 14.8 mmol g^(−1)(2.96 wt%)at 77 K and 0.1 MPa.This uptake is the highest among all the reported porous Zn-based MOF materials.Both experimental and theoretical results confirm that the reduced pore size derived from twofold interpenetration and the imidazole-functionalized ligand are responsible for the extremely high H_(2) uptake of UPC-501.