Investigation on the Distribution of Common Thalassemias in Various Cities and Counties under the Jurisdiction of Chongzuo City, Guangxi

Objective: To understand the distribution of thalassemia in all districts under the jurisdiction of Chongzuo City. Methods: Collect blood routine indicators from May 2014 to 31 December 2020 in the districts of this city to screen out suspected Mediterranean patients for genetic diagnosis;GGAP-PCR and PCR-reverse dot hybridization were used to analyze the thalassemia gene in the specimens of suspected patients;compare the prevalence of thalassemia in the counties and cities within the jurisdiction of this city, and provide corresponding medical advice to the health authorities. Results: 21,535 venous blood specimens from patients with suspected thalassemia were collected in the city. There were 14,215 positive cases of thalassemia, accounting for 66.01% of the total number of patients, among which 9455 cases (43.91%) were pure α gene positive. 3464 patients (16.09%) were positive for simple β gene. 1296 patients (6.02%) were positive for αβ double gene. The proportions of thalassemia gene testing for α-thalassaemia gene, β-thalassaemia gene, and α-β double gene in various counties and districts were different. According to the multiple rate or the chi-square test of the constituent ratio, the comparison of the distribution of the thalassaemia gene test results in each area, χ2 = 472.6917, P = 0.0000, the difference is statistically significant. Conclusion: Severe thalassemia is a tragedy for a family. It not only needs to spend a lot of money to prolong life, but it also cannot change the situation of losing life and financial emptiness in the end. It is suggested that timely screening, timely diagnosis and medical consultation should be carried out in married and unborn families and early pregnancy, so as to reduce the birth of children with severe thalassemia and avoid the occurrence of tragedies.

Usage Count： A New Indicator to Detect Research Fronts

Purpose： Research fronts build on recent work, but using times cited as a traditional indicator to detect research fronts will inevitably result in a certain time lag. This study attempts to explore the effects of usage count as a new indicator to detect research fronts in shortening the time lag of classic indicators in research fronts detection. Design/methodology/approach： An exploratory study was conducted where the new indicator ＂usage count＂ was compared to the traditional citation count, ＂times cited,＂ in detecting research fronts of the regenerative medicine domain. An initial topic search of the term ＂regenerative medicine＂ returned 10,553 records published between 2000 and 2015 in the Web of Science （WoS）. We first ranked these records with usage count and times cited, respectively, and selected the top 2,000 records for each. We then performed a co-citation analysis in order to obtain the citing papers of the co-citation clusters as the research fronts. Finally, we compared the average publication year of the citing papers as well as the mean cited year of the co-citation clusters. Findings： The citing articles detected by usage count tend to be published more recently compared with times cited within the same research front. Moreover, research fronts detected by usage count tend to be within the last two years, which presents a higher immediacy and real-time feature compared to times cited. There is approximately a three-year time span among the mean cited years （known as ＂intellectual base＂） of all clusters generated by usage count and this figure is about four years in the network of times cited. In comparison to times cited, usage count is a dynamic and instant indicator. Research limitations： We are trying to find the cutting-edge research fronts, but those generated based on co-citations may refer to the hot research fronts. The usage count of older highly cited papers was not taken into consideration, because the usage count indicator released by WoS only reflects usage logs after February 2013. Practical implications： The article provides a new perspective on using usage count as a new indicator to detect research fronts.Originality/value： Usage count can greatly shorten the time lag in research fronts detection, which would be a promising complementary indicator in detection of the latest research fronts.

Visible-light stimulated synaptic plasticity in amorphous indium−gallium−zinc oxide enabled by monocrystalline double perovskite for high-performance neuromorphic applications

Photoelectric synaptic devices have been considered as one of the key components in artificial neuromorphic systems due to their excellent capability to emulate the functions of visual neurons,such as light perception and image processing.Herein,we demonstrate an optically-stimulated artificial synapse with a clear photoresponse from ultraviolet to visible light,which is established on a novel heterostructure consisting of monocrystalline Cs2AgBiBr6 perovskite and indium–gallium–zinc oxide(IGZO)thin film.As compared with pure IGZO,the heterostructure significantly enhances the photoresponse and corresponding synaptic plasticity of the devices,which originate from the superior visible absorption of single-crystal Cs2AgBiBr6 and effective interfacial charge transfer from Cs2AgBiBr6 to IGZO.A variety of synaptic behaviors are realized on the fabricated thin-film transistors,including excitatory postsynaptic current,paired pulse facilitation,short-term,and long-term plasticity.Furthermore,an artificial neural network is simulated based on the photonic potentiation and electrical depression effects of synaptic devices,and an accuracy rate up to 83.8%±1.2%for pattern recognition is achieved.This finding promises a simple and efficient way to construct photoelectric synaptic devices with tunable spectrum for future neuromorphic applications.

具有超低开关电场的可控的易失性至非易失性单晶无铅双钙钛矿忆阻器

全无机无铅双钙钛矿由于其优异的电子传输能力、高光敏性、低毒性和环境稳定性,为电子/光电存储器件提供了潜在的材料.然而,钙钛矿薄膜的多晶性质严重限制了器件性能.在此,我们展示了一种基于单晶双钙钛矿Cs_(2)AgBiBr_(6)的高性能忆阻器,其具有6.67×10^(4)V m^(-1)的超低开关电场和10^(7)的高电流开/关比.值得注意的是,Cs_(2)AgBiBr_(6)的电阻开关行为与单晶钙钛矿的厚度相关,当单晶厚度从100到800 nm变化时,忆阻器从易失性的阈值开关行为演变为非易失性的忆阻开关行为.元素分析表明,Cs_(2)AgBiBr_(6)中导电通道的形成与具有低活化能Br空位的迁移有关.此外,形成的导电通道可以被具有不同波长和强度的光照湮灭,从而实现具有单独的电写入和光擦除的光电存储器.我们的研究结果为单晶钙钛矿中的离子迁移提供了深刻的见解,并为其在未来的电子和光电存储器中的应用提供了理论基础.

Infection of Ustilaginoidea virens intercepts rice seed formation but activates grain-filling-related genes

Rice false smut has become an increasingly serious disease in rice （Oryza sativa L.） production worldwide. The typical feature of this disease is that the fungal pathogen Ustilaginoidea virens （Uv） specifical y infects rice flower and forms false smut bal , the ustiloxin-containing bal-like fungal colony, of which the size is usual y several times larger than that of a mature rice seed. However, the underlying mechanisms of Uv-rice interac-tion are poorly understood. Here, we applied time-course microscopic and transcriptional approaches to investigate rice responses to Uv infection. The results demonstrated that the flower-opening process and expression of associated transcription factors, including ARF6 and ARF8, were inhibited in Uv-infected spikelets. The ovaries in infected spikelets were interrupted in fertilization and thus were unable to set seeds. However, a number of grain-fil ing-related genes, including seed storage protein genes, starch anabolism genes and endosperm-specific transcription factors （RISBZ1 and RPBF）, were highly transcribed as if the ovaries were fertilized. In addition, critical defense-related genes like NPR1 and PR1 were downregulated by;Uv infection. Our data imply that Uv may hijack host nutrient reservoir by activation of the grain-fil ing network because of growth and formation of false smut bal s.

Upper bound solution of supporting pressure for a shallow square tunnel based on the Hoek-Brown failure criterion

To analyze the stability of a shallow square tunnel, a new curved failure mechanism, representing the mechanical characteristics and collapsing form of this type of tunnel, is constructed. Based on the upper bound theorem of limit analysis and the Hoek-Brown nonlinear failure criterion, the supporting pressure derived from the virtual work rate equation is regarded as an objective function to achieve optimal calculation. By employing variational calculation to optimize the objective function, an upper bound solution for the supporting pressure and the collapsing block shape of a shallow square tunnel are obtained. To evaluate the validity of the failure mechanism proposed in this paper, the solutions computed by the curved failure mechanism are compared with the results calculated by the linear multiple blocks failure mechanism when the Hoek-Brown nonlinear failure criterion is converted into the Mohr-Coulomb linear criterion. The influences of rock mass parameters on the supporting pressure and collapsing block shape are discussed.

Overproduction of OsRACK1A,an effector-targeted scaffold protein promoting OsRBOHB-mediated ROS production,confers rice floral resistance to false smut disease without yield penalty

Grain formation is fundamental for crop yield but is vulnerable to abiotic and biotic stresses.Rice grain production is threatened by the false smut fungus Ustilaginoidea virens,which specifically infects rice floral organs,disrupting fertilization and seed formation.However,little is known about the molecular mechanisms of the U.virens-rice interaction and the genetic basis of floral resistance.Here,we report that U.virens secretes a cytoplasmic effector,UvCBP1,to facilitate infection of rice flowers.Mechanistically,UvCBP1 interacts with the rice scaffold protein OsRACK1A and competes its interaction with the reduced nicotinamide adenine dinucleotide phosphate oxidase OsRBOHB,leading to inhibition of reactive oxygen species(ROS)production.Although the analysis of natural variation revealed no OsRACK1A variants that could avoid being targeted by UvCBP1,expression levels of OsRACK1A are correlated with field resistance against U.virens in rice germplasm.Overproduction of OsRACK1A restores the OsRACK1A-OsRBOHB association and promotes OsRBOHB phosphorylation to enhance ROS production,conferring rice floral resistance to U.virens without yield penalty.Taken together,our findings reveal a new pathogenic mechanism mediated by an essential effector from a flower-specific pathogen and provide a valuable genetic resource for balancing disease resistance and crop yield.

Efficiently band-tailored type-Ⅲ van der Waals heterostructure for tunnel diodes and optoelectronic devices

Broken-gap(type-Ⅲ)two-dimensional(2D)van der Waals heterostructures(vdWHs)offer an ideal platform for interband tunneling devices due to their broken-gap band offset and sharp band edge.Here,we demonstrate an efficient control of energy band alignment in a typical type-ⅢvdWH,which is composed of vertically-stacked molybdenum telluride(MoTe2)and tin diselenide(SnSe2),via both electrostatic and optical modulation.By a single electrostatic gating with hexagonal boron nitride(hBN)as the dielectric,a variety of electrical transport characteristics including forward rectifying,Zener tunneling,and backward rectifying are realized on the same heterojunction at low gate voltages of±1 V.In particular,the heterostructure can function as an Esaki tunnel diode with a room-temperature negative differential resistance.This great tunability originates from the atomicallyflat and inert surface of h-BN that significantly suppresses the interfacial trap scattering and strain effects.Upon the illumination of an 885 nm laser,the band alignment of heterojunction can be further tuned to facilitate the direct tunneling of photogenerated charge carriers,which leads to a high photocurrent on/off ratio of>105 and a competitive photodetectivity of 1.03×1012 Jones at zero bias.Moreover,the open-circuit voltage of irradiated heterojunction can be switched from positive to negative at opposite gate voltages,revealing a transition from accumulation mode to depletion mode.Our findings not only promise a simple strategy to tailor the bands of type-ⅢvdWHs but also provide an in-depth understanding of interlayer tunneling for future low-power electronic and optoelectronic applications.