The Effect of Inlet Angle Structure of Concave and Convex Plate on Internal Flow Characteristics of Alkaline Electrolyzer

The structure of the concave-convex plates has proven to be crucial in optimizing the internal flow characteristics of the electrolyzer for hydrogen production.This paper investigates the impact of the gradual expansion angle of the inlet channel on the internal flow field of alkaline electrolyzers.The flow distribution characteristics of concave-convex plates with different inlet angle structures in the electrolytic cell is discussed.Besides,the system with internal heat source is studied.The results indicate that a moderate gradual expansion angle is beneficial for enhancing fluid uniformity.However,an excessively large gradual expansion angle may lead to adverse reflux phenomena,reducing the overall performance of the electrolytic cell.

The influences of biotic and abiotic factors on the occurrence and severity of poplar canker disease in Qingfeng County, China and the management implications

Landscape pathology is a research approach that can provide validation of the effectiveness of regional controls of forest disease at a landscape scale. In this paper, we analyzed the effects of stand features, management approaches, and geographical locations on poplar canker disease incidence （DI） and disease severity index （DSI） of individual trees at a 10 km x 10 km mesoscale landscape in Qingfeng County, China. DI varied significantly with stand age, tree densities, and the degree of canopy closure. DI in stands younger than 4 years old was significantly lower than that in the stands over 6 years old and reached the highest value at a stand age of 8-10 years. Overall, DI was positively correlated with stand age, stand density, andthe degree of canopy closure. DI was significantly lower in agro-forest stand patches than in other three patch types, i.e. isolated patch, pure stand patch, and mixed stand patch. Poplar plantations distributed around and near to villages exhibited significantly higher DI mainly due to human activities and herbivores. Fragmentation or connectivity in this mesoscale landscape seemed not impact disease occurrence. DSI was not significantly correlated with stand density, but varied significantly with tree varieties and trees ages. DSI was highest in stands of 10-12 year trees for all poplar varieties we studied here. Plantation density and plantation age were thus critical factors in determining DI and DSI. A logistic predictive model of disease occurrence was developed for the study area, considering varieties, age, height, density, canopy cover, stand types, patch types, management status, and stand geographical locations. Our study here shows that adjustment of stand density by thinning at different plantation ages is an effective approach controlling the occurrence canker disease in short-rotation poplar plantations at the landscape scale.

Narrow-band high-transmittance birefringent filter and its application in wide color gamut display

We propose a narrow-band birefringent filter and its application in wide color gamut.The birefringent filter consists of five phase retarders and two polarizers,and it has both narrow band and high transmittance.In the experiment,we fabricate the birefringent filter using quartz phase retarders and polarizers,and apply it in serval different displays.The color gamuts of displays are enhanced more than 30%NTSC(National Television System Committee),and the widest color gamuts that have been obtained are 126%NTSC in liquid crystal displays and 138%NTSC in organic light-emitting devices.Moreover,the deep blue light in spectrum of display can be reduced using the birefringent filter.The birefringent filter can be an efficient element to achieve wide color gamut display.

QTL mapping by whole genome re-sequencing and analysis of candidate genes for salt tolerance in linseed(Linum usitatissmum L.)

Soil salinization is detrimental to the growth and development of flax and ultimately leads to a decrease in yield.However,the molecular mechanism of linseed response to salt stress is still unclear.In this study,a salt-tolerant(ST)linseed variety STS and a salt-sensitive(SS)variety DYM were selected as experiment materials.Bulk segregation analysis and whole-genome resequencing technologies were performed to map salt tolerance quantitative trait loci(QTL).A total of 38,625 QTL loci were identified.Fifteen genes(which were not annotated in the reference genome)were identified within a 2.597 Mb region in chromosome 1.Two salt tolerance candidate genes Lus.o.m.scaffold91.141 and Lus.o.m.Scaffold1.14 encoding WD40 and cytochrome P450 were identified by predicting protein functions.Previous studies showed that WD40 and cytochrome P450 could significantly improve plant salt stress tolerance.In this paper,results showed that Lus.o.m.scaffold91.141 and Lus.o.m.Scaffold1.14 might be involved in response to salt stress in lineseed.The fine mapping and functional analysis of these genes provide a molecular breeding basis for the genetic improvement of high salt-tolerant linseed varieties.

Application of Criterion-Meeting Assessment Method in Fundamentals of Nursing

To investigate the results of criterion-meeting assessment method used for the operation test in fundamentals of nursing, 101 nursing undergraduates who entered Nursing College, Beihua University in 2007, were randomly divided into experimental group and control group. The students in the control group were examined with the traditional assessment method, namely, the points were given the students one-time and estimated in a way of quantitative analysis. The students in the experimental group were examined with criterion-meeting assessment methods. The average score of students in the experimental group was higher than that in the control group (P <0.001), the difference was statistically significant, and 100% students in the experimental group got 90-100 points of the assessment standards. Our studies suggest that the method is not only conducive to fully mobilizing the enthusiasm of the students and students’ establishing critical thinking, but also gives help to improve the overall quality of teachers. It can strengthen the experimental teaching, improve teachers’ and students’ senses of responsibility in teaching and learning and contribute to the good teaching result.

Seed filling dynamic traits of oil flax in response to nitrogen and phosphorus

Crop yield is primarily seed-filling-limited in production system under field conditions.This study was aimed to determine whether seed filling traits of oil flax(Linum usitatissimum L.)could be controlled by phosphorus(P),nitrogen(N),and phosphorus and nitrogen(NP)supply.Effects on seed filling traits were investigated in 2 years including capsule diameter,capsule height,capsule dry matter(DM),seed DM per capsule,pericarp DM per capsule,protein content and oil content.DM translocation from pericarps to seed,translocation efficiency,and contribution of photoassimilates during seed filling period were also detected.In a randomized complete block design,cultivar'Longyaza 1'was grown under P(33 kg P/ha),N(75 kg N/ha),and NP(33 kg P/ha and 75 kg N/ha)along with a zerofertilizer(CK)treatment in 2013 and 2014.Results suggested that DM translocation efficiency and contribution efficiency increased to different extent due to P,N or NP application.At 42 DAA(days after anthesis),seed DM per capsule reached the greatest,while protein content and pericarp DM obtained the least level.However,the highest oil content was detected at 35 DAA.A significant positive linear relationship was observed between seed DM,capsule DM and DM translocation in both years.Protein content showed inconsistent relation with oil content.The results indicated that appropriate N and P management could be an effective approach to increase oil flax production.

Secoisolariciresinol diglycoside(SDG)lignan content of oil flax:Genotypic and environmental variations and association with other traits

The secoisolariciresinol diglycoside(SDG)lignan of oil flax(Linum usitatissimum L.)is influenced by genotype,environment and the interaction of genotype×environment.This field study was conducted to investigate the effects of genotype and environment on the SDG lignan content,six genotypes(Longya 8,Zhangya 2,Linxiabai,Shandanbai,Gaolanbai,and DYMS)were sown under eight locations(Hohhot,Datong,Minle,Yili,Shuangta,Jingtai,Guyuan,and Zhangjiakou)in 2014 and 2015 in China.The experimental design was a randomized complete block with three replications.Results showed that Longya 8 had the highest SDG lignan content(7.27mg/g)and Shandanbai had the lowest(4.71 mg/g)across 16 environments.The SDG lignan content ranged from 4.70 mg/g at Datong to 7.74 mg/g at Minle Research Station.In the present study,the results indicated that differences among genotypes in SDG lignan content accounted for 51.38%variation of the total variation and environments accounted for 44.40%variation of the total variation.Moreover,we found that the altitude had a positive effect on SDG lignan content of flaxseed,presumably owing to differences in temperature,humidity,sunshine time,etc.These results indicated that the SDG lignan content was genetically controlled,and was also to be influenced by environmental conditions,especially altitude.

Detection and classification of breast lesions using multiple information on contrast-enhanced mammography by a multiprocess deep-learning system: A multicenter study

Objective: Accurate detection and classification of breast lesions in early stage is crucial to timely formulate effective treatments for patients. We aim to develop a fully automatic system to detect and classify breast lesions using multiple contrast-enhanced mammography(CEM) images.Methods: In this study, a total of 1,903 females who underwent CEM examination from three hospitals were enrolled as the training set, internal testing set, pooled external testing set and prospective testing set. Here we developed a CEM-based multiprocess detection and classification system(MDCS) to perform the task of detection and classification of breast lesions. In this system, we introduced an innovative auxiliary feature fusion(AFF)algorithm that could intelligently incorporates multiple types of information from CEM images. The average freeresponse receiver operating characteristic score(AFROC-Score) was presented to validate system’s detection performance, and the performance of classification was evaluated by area under the receiver operating characteristic curve(AUC). Furthermore, we assessed the diagnostic value of MDCS through visual analysis of disputed cases,comparing its performance and efficiency with that of radiologists and exploring whether it could augment radiologists’ performance.Results: On the pooled external and prospective testing sets, MDCS always maintained a high standalone performance, with AFROC-Scores of 0.953 and 0.963 for detection task, and AUCs for classification were 0.909[95% confidence interval(95% CI): 0.822-0.996] and 0.912(95% CI: 0.840-0.985), respectively. It also achieved higher sensitivity than all senior radiologists and higher specificity than all junior radiologists on pooled external and prospective testing sets. Moreover, MDCS performed superior diagnostic efficiency with an average reading time of 5 seconds, compared to the radiologists’ average reading time of 3.2 min. The average performance of all radiologists was also improved to varying degrees with MDCS assistance.Conclusions: MDCS demonstrated excellent performance in the detection and classification of breast lesions,and greatly enhanced the overall performance of radiologists.

具有次线性中立项的二阶阻尼微分方程的振动准则

该文研究如下具有次线性中立项的二阶阻尼微分方程的振动性(a(t)(z’(t))^(γ))’+b(t)(z’(t))^(γ)+q(t)^(β)(σ(t))=0,其中z(t)=x(t)+p(t)x^(α)(τ(t)).利用广义Riccati变换和不等式技巧建立了所考虑方程的新的振动准则,所得结果改进,推广了某些熟知的结果.也给出阐述所得结果意义的若干例子.

Challenge-based collaborative intrusion detection in software-defined networking: An evaluation

Software-Defined Networking(SDN)is an emerging architecture that enables a computer network to be intelligently and centrally controlled via software applications.It can help manage the whole network environment in a consistent and holistic way,without the need of understanding the underlying network structure.At present,SDN may face many challenges like insider attacks,i.e.,the centralized control plane would be attacked by malicious underlying devices and switches.To protect the security of SDN,effective detection approaches are indispensable.In the literature,challenge-based collaborative intrusion detection networks(CIDNs)are an effective detection framework in identifying malicious nodes.It calculates the nodes'reputation and detects a malicious node by sending out a special message called a challenge.In this work,we devise a challenge-based CIDN in SDN and measure its performance against malicious internal nodes.Our results demonstrate that such a mechanism can be effective in SDN environments.

Recycle of Wastewater from Lead-Zinc Sulfide Ore Flo-tation Process by Ozone/BAC Technology

Lead-zinc sulphide ore contains lead sulphide (galena), and zinc sulphide (sphalerite). In the first flotation stage, galena is rendered hydrophobic with an organic collector such as xanthate, while sphalerite is kept from floating by depressants, and in the second flotation stage, activator was used to activated zinc flotation. Since the organic regent used are different in the two flotation stage, wastewater from the second zinc flotation stage can’t be directly recycled to the first lead flotation stage. Wastewater from flotation process for concentrating lead-zinc sulphide ore often containing organic compounds such as diethyldithiocarbamate(DDTC), xanthate, terpenic oil(2# oil) and thionocarbamate esters (Z-200), are environmentally hazardous. Their removal from contaminated water and the reuse of the water is one of the main challenges facing lead-zinc sulphide ore processing plants. In this study, synthetic wastewater containing DDTC, xanthate, 2# oil and Z-200 at concentrations ranging from 21 to 42 mg/L was fed into an Ozone/Biological activated carbon (BAC) reactor. Analyses of the effluent indicated a chemical oxygen demand (COD) removal over 86.21% and Total organic carbon (TOC) removal over 90.00% were achieved under Hydraulic retention time (HRT) of 4h and O3 feeding concentration of 33.3mg/L. The effluent was further recycled to the lab scale lead concentrating process and no significant difference was found in compare with fresh water. Furthermore, lead-zinc sulphide mineral concentrating process was carried out at lab scale. The produced wastewater was treated by Ozone/BAC reactor at O3 feeding concentration of 16.7mg/L and HRT of 4h. The effluent analysis showed that TOC removal was 74.58%. This effluent was recycled to the lab scale lead-zinc sulphide mineral concentrating process and the recovery of lead was not affected. The results showed that by using Ozone/BAC technology, the lead-zinc sulphide mineral processing wastewater could be recycled.

A blockchain-empowered AAA scheme in the large-scale HetNet

A Large-Scale Heterogeneous Network(LS-HetNet)integrates different networks into one uniform network system to provide seamless one-world network coverage.In LS-HetNet,various devices use different technologies to access heterogeneous networks and generate a large amount of data.For dealing with a large number of access requirements,these data are usually stored in the HetNet Domain Management Server(HDMS)of the current domain,and HDMS uses a centralized Authentication/Authorization/Auditing(AAA)scheme to protect the data.However,this centralized method easily causes the data to be modified or disclosed.To address this issue,we propose a blockchain-empowered AAA scheme for accessing data of LS-HetNet.Firstly,the account address of the blockchain is used as the identity authentication,and the access control permission of data is redesigned and stored on the blockchain,then processes of AAA are redefined.Finally,the experimental model on Ethereum private chain is built,and the results show that the scheme is not only secure but also decentral,without tampering and trustworthiness.

Updated thoughts on SARS-CoV-2 and coronavirus therapies,fighting and surviving

From late December 2019 a new human-adapted coronavirus,SARS-CoV-2,was observed and isolated in clustered patients in Wuhan,China.It has been proved to be able to transmit human-to-human and cause pneumonia,leading to about 2%fatality.Its genome characteristics,immune responses and related potential treatments,such as chemical drugs,serum transfusion and vaccines including DNA vaccines,are discussed in this review for a brief summary.

Redox Factor-1 Mediates Inflammatory Response during Tumor Promotion in Skin Epidermal JB6 Cells

Recently, redox factor-1 (Ref-1) has received considerable attention as an enzyme for stimulating tumor cell growth. We hypothesized that Ref-1 is upregulated during the early stage of tumorigenesis. Utilizing both tumor promotion sensitive P+ and promotion resistant P? mouse skin epidermal JB6 cells, we found that Ref-1 expression was only induced in tumor promotion sensitive P+ cells following TPA treatment. Consistent with that, Ref-1 knockdown suppressed skin cell transformation. Interestingly, Ref-1 knockdown suppressed nuclear translocation of NF-kappaB subunit p65, and inhibited production of proinflammatory cytokines. These results suggest Ref-1 may promote early tumorigenesis and serve as a target for chemoprevention.

Controllable preparation of graphene glass fiber fabric towards mass production and its application in self-adaptive thermal management

Direct synthesis of graphene on nonmetallic substrates via chemical vapor deposition (CVD) has become a frontier research realm targeting transfer-free applications of CVD graphene.However,the stable mass production of graphene with a favorable growth rate and quality remains a grand challenge.Herein,graphene glass fiber fabric (GGFF) was successfully developed through the controllable growth of graphene on non-catalytic glass fiber fabric,employing a synergistic binary-precursor CVD strategy to alleviate the dilemma between growth rate and quality.The binary precursors consisted of acetylene and acetone,where acetylene with high decomposition efficiency fed rapid graphene growth while oxygencontaining acetone was adopted for improving the layer uniformity and quality.Notably,the bifurcating introducing-confluent premixing (BI-CP) system was self-built for the controllable introduction of gas and liquid precursors,enabling the stable production of GGFF.GGFF features solar absorption and infrared emission properties,based on which the self-adaptive dual-mode thermal management film was developed.This film can automatically switch between heating and cooling modes by spontaneously perceiving the temperature,achieving excellent thermal management performances with heating and cooling power of~501.2 and~108.6 W m-2,respectively.These findings unlock a new strategy for the large-scale batch production of graphene materials and inspire advanced possibilities for further applications.

Co-enhancement of thermal conduction and radiation through morphologies controlling of graphene functional layer for chip thermal management

With the continuous advancements in electronics towards downsizing and integration,efficient thermal dissipation from chips has emerged as a critical factor affecting their lifespan and operational efficiency.The fan-less chip cooling system has two critical interfaces for thermal transport,which are the contact interface between the base and the chip dominated by thermal conduction,and the surface of the fins dominated by thermal radiation.The different thermal transfer modes of these two critical interfaces pose different requirements for thermal management materials.In the study,a novel approach was proposed by developing graphene thermal transport functional material whose morphology could be intentionally designed via reformed plasmaenhanced chemical vapor deposition(PECVD)methods to meet the diverse requirements of heat transfer properties.Specifically,graphene with multilevel branching structure of vertical graphene(BVG)was fabricated through the hydrogenassisted PECVD(H_(2)-PECVD)strategy,which contributed a high emissivity of~0.98.BVG was deposited on the fins’surface and functioned as the radiation enhanced layer to facilitate the rapid radiation of heat from the heat sinks into the surrounding air.Meanwhile,the well-oriented vertical graphene(OVG)was successfully prepared through the vertical electric field-assisted PECVD process(EF-PECVD),which showed a high directional thermal conductivity of~53.5 W·m^(-1)·K^(-1).OVG was deposited on the contact interface and functioned as the thermal conduction enhanced layer,allowing for the quick transmission of heat from the chip to the heat sink.Utilizing this design concept,the two critical interfaces in the chip cooling system can be jointly enhanced,resulting in a remarkable cooling efficiency enhancement of~30.7%,demonstrating that this novel material possessed enormous potential for enhancing the performance of cooling systems.Therefore,this research not only provided new design concepts for the cooling system of electronic devices but also opened up new avenues for the application of graphene materials in thermal management.

Heterologous prime-boost with AdC68- and mRNA-based COVID-19 vaccines elicit potent immune responses in mice

Dear Editor An optimal vaccination program that can elicit Iong-lasting humoral and cellular immune response is key to Iong-term prevention of coronavirus disease 2019(COVID-19).Multiple variants of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)continue to emerge.The neutralizing capacities of available COVID-19 vaccines against these variants have declined.^(1) In such a scenario,heterologous prime-boost programs for COVID-19 vaccines have attracted considerable interest.

Fractional Fourier transform on R^(2)and an application

We focus on the L^(p)(R^(2))theory of the fractional Fourier transform(FRFT)for 1≤p≤2.In L^(1)(R^(2)),we mainly study the properties of the FRFT via introducing the two-parameter chirp operator.In order to get the pointwise convergence for the inverse FRFT,we introduce the fractional convolution and establish the corresponding approximate identities.Then the well-defined inverse FRFT is given via approximation by suitable means,such as fractional Gauss means and Able means.Furthermore,if the signal F_(α,β)f is received,we give the process of recovering the original signal f with MATLAB.In L^(2)(R^(2)),the general Plancherel theorem,direct sum decomposition,and the general Heisenberg inequality for the FRFT are obtained.

Coherent control of spin tunneling in a driven spin–orbit coupled bosonic triple well

We investigate the coherent control of spin tunneling for a spin–orbit(SO)coupled boson trapped in a driven triple well.In the high-frequency limit,the quasienergies of the system are obtained analytically and the fine energy band structures are shown.By regulating the driving parameters,we reveal that the directed spin-flipping or spin-conserving tunneling of an SOcoupled boson occurs along different pathways and in different directions.The analytical results are demonstrated by numerical simulations and good agreements are found.Further,an interesting scheme of quantum spin tunneling switch with or without spin-flipping is presented.The results may have potential applications in the design of spintronic devices.

Axial spondyloarthritis:synthetic magnetic resonance imaging in the detection of sacroiliac joint lesions

To the Editor:Axial spondyloarthritis(axSpA)is characterized by sacroiliac joint inflammation,spine inflammation,bone destruction,and osteogenesis.Ankylosis of the spine and/or hip joints may occur later,significantly affecting the patient’s quality of life.As the earliest and most common imaging finding of axSpA,sacroiliitis can be divided into early active and late structural lesions.Magnetic resonance imaging(MRI)not only detects active inflammatory changes that cannot be found in computed tomography(CT)or X-rays but also has a similar sensitivity to CT in detecting structural lesions.