Evaluation of the Global and Regional Assimilation and Prediction System for Predicting Sea Fog over the South China Sea

In the South China Sea, sea fog brings severe disasters every year, but forecasters have yet to implement an effective seafog forecast. To address this issue, we test a liquid-water-content-only(LWC-only) operational sea-fog prediction method based on a regional mesoscale numerical model with a horizontal resolution of about 3 km, the Global and Regional Assimilation and Prediction System(GRAPES), hereafter GRAPES-3 km. GRAPES-3 km models the LWC over the sea, from which we infer the visibility that is then used to identify fog. We test the GRAPES-3 km here against measurements in 2016 and 2017 from coastal-station observations, as well as from buoy data, data from the Integrated Observation Platform for Marine Meteorology, and retrieved fog and cloud patterns from Himawari-8 satellite data. For two cases that we examine in detail, the forecast region of sea fog overlaps well with the multi-observational data within 72 h. Considering forecasting for0–24 h, GRAPES-3 km has a 2-year-average equitable threat score(ETS) of 0.20 and a Heidke skill score(HSS) of 0.335,which is about 5.6%(ETS) and 6.4%(HSS) better than our previous method(GRAPES-MOS). Moreover, the stations near the particularly foggy region around the Leizhou Peninsula have relatively high forecast scores compared to other sea areas.Overall, the results show that GRAPES-3 km can roughly predict the formation, evolution, and dissipation of sea fog on the southern China coast.

植物基因组编辑检测方法

以CRISPR/Cas9技术为代表的基因组编辑在生物领域的革命性应用使得生命科学研究迈入新篇章。该技术以其灵活性、易用性且扩展性强等优势,大大加快了基因工程研究,也加速了植物分子育种的步伐。但是,遗传转化过程中产生大量潜在的基因编辑植株,使得早期高通量快速筛选和检测目标编辑植株面临很大挑战。本文综述了近年来植物基因组编辑检测的各种方法,比较了其优缺点和适用范围;同时,还对近几年植物基因组编辑检测方法的发展趋势进行了深入分析和展望,以期对基因组编辑技术在植物中的应用提供参考。

A Programmable Hybrid DNA Nanogel for Enhanced Photodynamic Therapy of Hypoxic Glioma

Photodynamic therapy(PDT)is a promising cancer therapy due to the evident advantages of a rapid curative eff ect,minimal or non-invasiveness,and circumvention of drug resistance.However,the hydrophobicity of photosensitizers and the hypoxic tumor microenvironment in solid tumors reduce the therapeutic eff ect of PDT immensely.Herein,we construct a programmable hybrid mesoporous silica nanoparticle/DNA nanogel(H-DNA nanogel)for enhanced PDT.The H-DNA nanogel is constituted with a virus-like mesoporous silica nanoparticle(VMSN)as the core to provide an appropriate nano-interface and a self-assembly programmable DNA hydrogel layer based on rolling circle amplifi cation(RCA)as the shell.Two kinds of G-quadruplex structures inserted with a hemin and zinc phthalocyanine(ZnPc)photosensitizer are introduced into the H-DNA nanogel by base pairing.The two modules of G-quadruplex structure work as an oxygen supplement in the hypoxic tumor microenvironment and increase the yield of singlet oxygen,respectively.Our hybrid DNA nanogel system provides a modular platform for effi cient cancer PDT and has great potential in the broader biomedical fi eld.

A nanoplatform with oxygen self-supplying and heat-sensitizing capabilities enhances the efficacy of photodynamic therapy in eradicating multidrug-resistant biofilms

Bacterial biofilms,especially those caused by multidrug-resistant bacteria,have emerged as one of the greatest dangers to global public health.The acceleration of antimicrobial resistance to conventional an-tibiotics and the severe lack of new drugs necessitates the development of novel agents for biofilm eradication.Photodynamic therapy(PDT)is a promising non-antibiotic method for treating bacterial infections.However,its application in biofilm eradication is hampered by the hypoxic microenvironment of biofilms and the physical protection of extracellular polymeric substances.In this study,we develop a composite nanoplatform with oxygen(O_(2))self-supplying and heat-sensitizing capabilities to improve the PDT efficacy against biofilms.CaO_(2)/ICG@PDA nanoparticles(CIP NPs)are fabricated by combining calcium peroxide(CaO_(2))with the photosensitizer indocyanine green(ICG)via electrostatic interactions,followed by coating with polydopamine(PDA).The CIP NPs can gradually generate O_(2)in response to the acidic microenvironment of the biofilm,thereby alleviating its hypoxic state.Under near-infrared(NIR)irradiation,the nanoplatform converts O_(2)into a significant amount of singlet oxygen(^(1)O_(2))and heat to eradicate biofilm.The generated heat enhances the release of O_(2),accelerates the generation of^(1)O_(2)in PDT,increases cell membrane permeability,and increases bacterial sensitivity to^(1)O_(2).This nanoplatform significantly improves the efficacy of PDT in eradicating biofilm-dwelling bacteria without fostering drug resistance.Experiments on biofilm eradication demonstrate that this nanoplatform can eradicate over 99.9999%of methicillin-resistant Staphylococcus aureus(MRSA)biofilms under 5-min NIR irradiation.Notably,these integrated advantages enable the system to promote the healing of MRSA biofilm-infected wounds with negligible toxicity in vivo,indicating great promise for overcoming the obstacles associated with bacterial biofilm eradication.

An injectable alginate/fibrin hydrogel encapsulated with cardiomyocytes and VEGF for myocardial infarction treatment

Myocardial infarction(MI)is one of the typical cardiovascular diseases,which persist as the leading cause of death globally.Due to the poor regenerative capability of endogenous cardiomyocytes(CMs),the transplantation of exogenous CMs becomes a promising option for MI treatment.However,the low retention and survival of transplanted cells still limit the clinical translation of cell therapy.Herein,an alginate/fibrin-based injectable hydrogel was prepared for the delivery of neonatal CMs and an angiogen-esis agent vascular endothelial growth factor(VEGF)locally to the infarcted area of the heart.This hydro-gel combined the specific advantages of alginate and fibrin with proper mechanical properties and cell affinity,showing good biocompatibility to support the retention and integration of the transplanted CMs to the host myocardium.Moreover,the delivered VEGF was favorable for the blood recovery to mitigate the ischemic microenvironment of the infarcted area and thus improved the survival of the transplanted CMs.Intramyocardial injection of this hydrogel to the infarcted area of the heart promoted angiogenesis,inhibited fibrosis,and improved cardiac function,exhibiting great potential for MI treatment.

Bacterial cellulose-based dressings with photothermal bactericidal activity and pro-angiogenic ability for infected wound healing

For most traditional wound dressings,it is challenging to simultaneously eliminate bacteria and promote angiogenesis to accelerate the healing process of bacteria-infected wounds.In this work,we develop a multifunctional dressing based on bacterial cellulose(BC)deposited with a tannic acid/Cu^(2+)ion/Mg^(2+)ion(TCM)complex film.Overall,the TCM complex exhibits robust interfacial adhesion to modify BC and good photothermal properties to effectively eradicate bacteria in the wound area under near-infrared(NIR)irradiation.The individual components of the TCM complex have several advantageous features for wound healing,such as antibacterial ability and negligible cytotoxicity;in particular,the released Cu^(2+)and Mg^(2+)ions are favorable for the proliferation,migration,and tube formation of endothelial cells in vitro.The results of in vivo experiments demonstrated that with the assistance of NIR irradiation,this composite dressing is more effective than traditional gauze or pristine BC dressing in promotion of angiogenesis and collagen deposition without causing remarkable inflammation,thereby accelerating the healing process of bacteria-infected full-thickness skin wounds.This work thus provides a simple and facile way to fabricate multifunctional BC-based dressings that could be potentially used for treating infected wounds.

Injectable decellularized extracellular matrix hydrogel loaded with exosomes encapsulating curcumin for prevention of cardiac fibrosis after myocardial infarction

Excessive cardiac fibrosis impairs cardiac repair after myocardial infarction(MI).In this work,an in-jectable composite hydrogel integrating natural biomaterials,exosomes,and bioactive molecules is de-veloped to prevent or alleviate cardiac fibrosis.Curcumin,a natural molecule with antifibrotic activity,is encapsulated in the exosomes that are isolated from bone marrow-derived mesenchymal stem cells to enhance its water solubility and bioavailability.These composite exosomes are efficiently internalised by fibroblasts and effectively inhibit their transition to myofibroblasts in vitro.Decellularized porcine cardiac extracellular matrix(dECM)hydrogel is used as the carrier for delivering these composite exosomes to the infarcted myocardium,not only improving the retention of exosomes but also providing mechani-cal support and structural protection.Injection of this hydrogel into the infarcted heart of a mouse MI model leads to a decrease in collagen deposition,alleviation of fibrosis,a reduction in infarct size,and an improvement in cardiac function.The reported composite hydrogel comprising natural materials and biomolecules exhibits good biocompatibility and bioactivity.Altogether,this study demonstrates that the dECM hydrogel is a suitable platform for the local delivery of antifibrotic biomolecule-encapsulating exo-somes to prevent myocardial fibrosis after MI and have great potential for the treatment of MI in clinical settings.

2018年中国基本城市土地利用类型制图(EULUC-China)

土地利用是人类活动在土地空间的重要表现形式.由于数据和资金支持的限制,全国尺度城市土地利用的遥感制图研究仍相对缺乏.针对这一难题,本文提出了涵盖居住-休闲-交通-工业-办公五大类用地的"基本城市土地利用类型(EULUC)"的概念,并综合利用2018年的10米分辨率哨兵卫星数据,OpenStreetMap,珞珈一号夜间灯光数据,以及腾讯移动定位和高德兴趣点(POI)等社会大数据,实现了全国范围内城市土地利用制图.第一版中国基本城市土地利用制图结果共包括440798个地块(除道路用地),5大一级类和12个二级类总体分类精度分别为61.2%和57.5%.这是中国首套结合遥感和众源大数据,以地块尺度生产的面向对象的高分辨率城市土地利用图.

High-Resolution Genome-wide Association Study Identifies Genomic Regions and Candidate Genes for Important Agronomic Traits in Wheat

Wheat(Triticum aestivum)is a major staple food crop worldwide.Genetic dissection of important agronomic traits is essential for continuous improvement of wheat yield to meet the demand of the world's growing population.We conducted a large-scale genome-wide association study(GWAS)using a panel of 768 wheat cultivars that were genotyped with 327609 single-nucleotide polymorphisms generated by genotyping-by-sequencing and detected 395 quantitative trait loci(QTLs)for 12 traits under 7 environments.Among them,273 QTLs were delimited to≤1.0-Mb intervals and 7 of them are either known genes(Rht-D,Vrn-B1,and Vrn-D1)that have been cloned or known QTLs(TaGA2ox8,APO1,TaSus1-7B,and Rht12)that were previously mapped.Eight putative candidate genes were identified for three QTLs that enhance spike seed setting and grain size using gene expression data and were validated in three bi-parental populations.Protein sequence analysis identified 33 putative wheat orthologs that have high identity with rice genes in QTLs affecting similar traits.Large r^2 values for additive effects observed among the QTLs for most traits indicated that the phenotypes of these identified QTLs were highly predictable.Results from this study demonstrated that significantly increasing GWAS population size and marker density greatly improves detection and identification of candidate genes underlying a QTL,solidifying the foundation for large-scale QTL fine mapping,candidate gene validation,and developing functional markers for genomics-based breeding in wheat.

Histology and antitumor activity study of PTX-loaded micelle,a fluorescent drug delivery system prepared by PEG-TPP

We synthesized PEG-TPP as carrier to encapsulate paclitaxel (PTX) in the form of micelles to overcome its water-solubility problem. PTX-loaded micelles possess a-week stability and appropriate particle size (152.1 ±1.2 nm) which is beneficial for enhanced permeability and retention (EPR) effect. Strong pH dependence of PTX releasing from micelles is verified by in vitro release study. At cellular level, PTX-loaded micelles can target mitochondria effectively which may results a better cytotoxicity of micelles (especially IC50 = 0.123 ± 0.035μmol/L of micelles and 0.298 ± 0.067μmol/L of PTX alone on MCF-7 cells). The fluorescence distributions of both isolated and sliced organs show that the micelles can effectively target tumors. Moreover, we further prove the enhanced therapeutic effects of micelles in tumor-bearing mice comparing with PTX alone. The results show that the biodegradable drug delivery system prepared by PEG-TPP can overcome the poor solubility of paclitaxel and improve its tumor targeting and antitumor activity.

Biomaterials based cardiac patches for the treatment of myocardial infarction

Myocardial infarction(MI)is one of the common cardiovascular diseases that occurs with a blockage in one or more of the coronary arteries to lead to the damage of the myocardium,resulting in a lifethreatening condition.To repair the damaged myocardium in MI,researchers are looking forwards to new ways to postpone the progression of myocardial injury.Cardiac patches,the scaffolds layered on the heart surface,can provide mechanical support for the infarction site and improve cardiac function by delivering various bioactive factors or cells,showing considerable curative effect in the treatment of MI.Biomaterials with certain biocompatibility and mechanical properties have received widespread attention for the application in cardiac patches.In this review,we focus on the recent progress on these biomaterialsbased cardiac patches,which could be categorized into two types according to the sources of materials including(ⅰ)natural materials and(ⅱ)synthetic materials.The major advantages and current challenges of each type are discussed and a brief perspective on the future research directions is presented.

Ensemble Based Diagnosis of the Track Errors of Super Typhoon Mangkhut(2018)

Super Typhoon Mangkhut(2018)was the most high-impact typhoon in 2018 because of its long lifespan and significant intensity.The operational track forecasts in the short-to-medium range(deterministic and probabilistic forecast)showed a great uncertainty and the forecast landing points varied with different lead times.This study applied ensembles of high-resolution ECMWF forecasts to investigate the major factors and mechanisms of the bias production of the Mangkhut forecast track.The ensembles with the largest track bias were analyzed to examine the possible bias associated factors.The results suggested that environmental steering flows were the main cause for the erroneous southward track error with a variance contribution of 72%.The tropical cyclone(TC)size difference and the interaction of the TC with the subtropical high(SH)were other two key factors that contributed to the track error.Particularly,larger TCs may have led to a stronger erosion of the southern part of the SH,and thus induced significant changes in the large-scale environment and eventually resulted in an additional northward movement of TC.

Evaluation of the Impact of Observations on Blended Sea Surface Winds in a Two-Dimensional Variational Scheme Using Degrees of Freedom

This paper presents an evaluation of the observational impacts on blended sea surface winds from a two- dimensional variational data assimilation （2D-Var） scheme. We begin by briefly introducing the analysis sensitivity with respect to observations in variational data assimilation systems and its relationship with the degrees of freedom for signal （DFS）, and then the DFS concept is applied to the 2D-Var sea surface wind blending scheme. Two meth- ods, a priori and a posteriori, are used to estimate the DFS of the zonal （u） and meridional （v） components of winds in the 2D-Var blending scheme. The a posteriori method can obtain almost the same results as the a priori method. Because only by-products of the blending scheme are used for the a posteriori method, the computation time is re- duced significantly. The magnitude of the DFS is critically related to the observational and background error statistics. Changing the observational and background error variances can affect the DFS value. Because the observation error variances are assumed to be uniform, the observational influence at each observational location is related to the background error variance, and the observations located at the place where there are larger background error variances have larger influences. The average observational influence of u and v with respect to the analysis is about 40%, implying that the background influence with respect to the analysis is about 60%.