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Green sulfur bacteria (GSB) are a distinct group of anoxygenic phototrophic bacteria that are found in many ecological niches. Prosthecochloris, a marine representative genus of GSB, was found to be dominant in some coral skeletons. However, how coral-associated Prosthecochloris (CAP) adapts to diurnal changing microenvironments in coral skeletons is still poorly understood. In this study, three Prosthecochloris genomes were obtained through enrichment culture from the skeleton of the stony coral Galaxea fascicularis. These divergent three genomes belonged to Prosthecochloris marina and two genomes were circular. Comparative genomic analysis showed that between the CAP and non-CAP clades, CAP genomes possess specialized metabolic capacities (CO oxidation, CO2 hydration and sulfur oxidation), gas vesicles (vertical migration in coral skeletons), and cbb3-type cytochrome c oxidases (oxygen tolerance and gene regulation) to adapt to the microenvironments of coral skeletons. Within the CAP clade, variable polysaccharide synthesis gene clusters and phage defense systems may endow bacteria with differential cell surface structures and phage susceptibility, driving strain-level evolution. Furthermore, mobile genetic elements (MGEs) or evidence of horizontal gene transfer (HGT) were found in most of the genomic loci containing the above genes, suggesting that MGEs play an important role in the evolutionary diversification between CAP and non-CAP strains and within CAP clade strains. Our results provide insight into the adaptive strategy and population evolution of endolithic Prosthecochloris strains in coral skeletons.

In the research on the study of higher vocational students' learning ability, the researchers mainly focus on the cultivation of learning ability and the analysis of the current situation. With the deepening of research and attention on vocational students' learning ability, learning ability plays a more and more significant role in the lifelong learning and future sustainable development of vocational college students. Higher vocational students learning ability training strategy research should be the focus of attention and research, the current research is mostly using the questionnaire survey students learning status and problems and put forward the corresponding training promotion method, the lack of related system of theoretical support, the future research focus should be based on time development, higher vocational colleges and students' thought and behavior characteristics, the scientific system related theory as guidance and support, discusses the path of system improve students learning method, in order to better improve higher vocational colleges to cultivate innovative practice skills talent education effect.

Abiotic stresses and climate changes cause severe loss of yield and quality of crops and reduce the production area worldwide. Flooding stress curtails soybean growth, yield, and quality and ultimately threatens the global food supply chain. Flooding tolerance is a multigenic trait. Tremendous research in molecular breeding explored the potential genomic regions governing flood tolerance in soybean. The most robust way to develop flooding tolerance in soybean is by using molecular methods, including quantitative trait loci (QTL) mapping, identification of transcriptomes, transcription factor analysis, CRISPR/Cas9, and to some extent, genome-wide association studies (GWAS), and multi-omics techniques. These powerful molecular tools have deepened our knowledge about the molecular mechanism of flooding stress tolerance. Besides all this, using conventional breeding methods (hybridization, introduction, and backcrossing) and other agronomic practices is also helpful in combating the rising flooding threats to the soybean crop. The current review aims to summarize recent advancements in breeding flood-tolerant soybean, mainly by using molecular and conventional tools and their prospects. This updated picture will be a treasure trove for future researchers to comprehend the foundation of flooding tolerance in soybean and cover the given research gaps to develop tolerant soybean cultivars able to sustain growth under extreme climatic changes.

The soybean is a significant legume crop, providing several vital dietary components. Extreme heat stress negatively affects soybean yield and quality, especially at the germination stage. Continuous change in climatic conditions is threatening the global food supply and food security. Therefore, it is a critical need of time to develop heat-tolerant soybean genotypes. Different molecular techniques have been developed to improve heat stress tolerance in soybean, but until now complete genetic mechanism of soybean is not fully understood. Various molecular methods, like quantitative trait loci (QTL) mapping, genetic engineering, transcription factors (TFs), transcriptome, and clustered regularly interspaced short palindromic repeats (CRISPR), are employed to incorporate heat tolerance in soybean under the extreme conditions of heat stress. These molecular techniques have significantly improved heat stress tolerance in soybean. Besides this, we can also use specific classical breeding approaches and different hormones to reduce the harmful consequences of heat waves on soybean. In future, integrated use of these molecular tools would bring significant results in developing heat tolerance in soybean. In the current review, we have presented a detailed overview of the improvement of heat tolerance in soybean and highlighted future prospective. Further studies are required to investigate different genetic factors governing the heat stress response in soybean. This information would be helpful for future studies focusing on improving heat tolerance in soybean.

Although conbercept has been used for other diseases associated with new vascular formation, the effect of single-dose conbercept in combination with proliferative diabetic retinopathy (PDR) have not been established. We thus conducted this protocol for systematic review and meta-analysis to compare the efficacy and acceptability of panretinal photocoagulation (PRP) associated with intravitreal conbercept injections versus PRP alone in the treatment of patients with PDR.

The soybean is a significant legume crop, providing several vital dietary components. Extreme heat stress negatively affects soybean yield and quality, especially at the germination stage. Continuous change in climatic conditions is threatening the global food supply and food security. Therefore, it is a critical need of time to develop heat-tolerant soybean genotypes. Different molecular techniques have been developed to improve heat stress tolerance in soybean, but until now complete genetic mechanism of soybean is not fully understood. Various molecular methods, like quantitative trait loci (QTL) mapping, genetic engineering, transcription factors (TFs), transcriptome, and clustered regularly interspaced short palindromic repeats (CRISPR), are employed to incorporate heat tolerance in soybean under the extreme conditions of heat stress. These molecular techniques have significantly improved heat stress tolerance in soybean. Besides this, we can also use specific classical breeding approaches and different hormones to reduce the harmful consequences of heat waves on soybean. In future, integrated use of these molecular tools would bring significant results in developing heat tolerance in soybean. In the current review, we have presented a detailed overview of the improvement of heat tolerance in soybean and highlighted future prospective. Further studies are required to investigate different genetic factors governing the heat stress response in soybean. This information would be helpful for future studies focusing on improving heat tolerance in soybean.

Single crystalline lithium niobate (LN) thin films with a Y43-cut are fabricated by crystal-ion-slicing technique, and the B-staged benzocyclobutene (BCB) polymer is used as the bonding medium for the transferring of the LN thin film on to a homogeneous LN substrate. The thickness of the LN film is about 910 nm, and low energy ion irradiation is used to treat the surface of the film, which reduces the roughness from 12.4 nm down to 3.6 nm. Bulk acoustic wave (BAW) resonator is fabricated based on the thin LN layer, and the electromechanical coefficient (k2t) of the LN film reaches 16.3%. A 3-stage BAW filter is obtained, and the 3 dB bandwidth of the filter is 8.5%, demonstrating the single crystalline LN thin film with large k2t is promising for wide band filter.

Additional file 5: Table S2. The main clinical manifestations in patients with ovarian strumal carcinoid (n = 79).

Additional file 6: Table S3. Univariate and multivariate analysis of survival outcomes.

Additional file 4: Table S1. Database of our study.

Additional file 1: Figure S1. PRISMA flow diagram.

China’s first Mars rover, Zhurong, has successfully touched down on the southern Utopia Planitia of Mars at 109.925° E, 25.066° N, and since performed cooperative multiscale investigations with the Tianwen-1 orbiter. Here we present primary localization and surface characterization results based on complementary data of the first 60 sols. The Zhurong rover has traversed 450.9 m southwards over a flat surface with mild wheel slippage (less than 0.2 in slip ratio). The encountered crescent-shaped sand dune indicates a NE-SW local wind direction, consistent with larger-range remote-sensing observations. Soil parameter analysis based on terramechanics indicates that the topsoil has high bearing strength and cohesion, and its equivalent stiffness and internal friction angle are ~1390-5872 kPa∙m-n and ~21°-34° respectively. Rocks observed strewn with dense pits, or showing layered and flaky structures, are presumed to be involved in physical weathering like severe wind erosion and potential chemical weathering processes. These preliminary observations suggest great potential of in-situ investigations by the scientific payload suite of the Zhurong rover in obtaining new clues of the region’s aeolian and aqueous history. Cooperative investigations using the related payloads on both the rover and the obiter could peek into the habitability evolution of the northern lowlands on Mars.

The unloaded quality factor is used to describe the performance for frequency selection of microwave resonant cavity, and the precise measurement of it is the basis of resonator design. The current traditional measurement method usually has limitations on single-port microwave resonators. In this paper, the traditional method was improved. According to the derived group delay formula, the relationship between the coupling coefficient and the standing wave ratio was judged. The obtained coupling coefficient determined the calculation formula of the unloaded quality factor, thereby obtaining a series of unloaded quality corresponding to different bandwidths. The data within the credible interval were processed to obtain a stable unloaded quality factor with small errors. We applied the improved method to measure and calculate the simulation and experimental results of single-port resonator cavity, which confirms the accuracy and reliability of this method.

Conventional intra coding is retained in depth map prediction while depth modeling mode is introduced. Depth map intra coding has a heavy computational burden. Depth modeling mode can be omitted based on DC or Planar mode with the minimum sum of absolutely transform distortion. According to the relationship between angle mode and wedgelet orientation, the wedgelet direction is roughly selected. We make use of boundary gradient method to choose wedgelet pattern segmentation. The experimental results introduce that synthetic viewpoint bit rate increases by 0.62% and the encoding time decreases by 30.1% compared with HTM16.0. Compared with other algorithms, the time saving is slightly higher than other algorithms.

The soybean is one of the most widely grown legume crops which serves as a source of protein and oil. Soybean production has increased in recent years due to several breeding techniques. The use of conventional breeding approaches does not fulfil the rapidly growing demand of the world population. Newly developed genomic approaches opened the windows of opportunities to bring more genetic variation in soybean germplasm. Clustered regularly interspaced short palindromic repeats (CRISPR) has emerged as a renowned gene-editing tool that has broadened soybean research. CRISPR/Cas9 has been extensively applied to improve several essential traits in soybeans. Soybean yield, quality, and other agronomic traits have been enhanced, and research is being conducted to revolutionize the genomic area of soybeans. The development of specific soybean mutants has shown better yield and quality. In this review, we have enlisted the potential use of clustered regularly interspaced short palindromic repeats (CRISPR) in soybean improvement and highlighted the significant future prospective. Research of applied sciences revealed that CRISPR/Cas9 could improve the traits of the commercially essential soybean crop, including yield, quality, and resistance to certain biotic and abiotic factors. The use of this tool has lifted the scope of genome editing and laid a foundation for the bright future of human beings. This updated review will be helpful for future research studies focusing on the successful use of CRISPR/Cas9 in soybeans.

The spotted wing drosophila, Drosophila suzukii Matsumura, which is widely spread in the main soft-skinned fruits production areas in China, presents a threat to importing countries. In order to develop a phytosanitary cold treatment measure for preventing the movement of this drosophila fly, cold tolerance of six immature life stages of D. suzukii was compared followed by time-mortality and large-scale confirmatory tests on the most tolerant stage in grape fruit. Egg was defined as the most cold-tolerant stage by comparing the mortality of all the immature stages (egg, first, second, and third instars, early and late pupa) treated at 0 and 2°C. The minimal lethal time (LT) for 99.9968% mortality (95% confidence level [CL]) estimated by the probit model was 10.47 d at 0°C and 11.92 d at 2°C, respectively. Hence, 11 d (at 0°C) and 12 d (at 2°C) were chosen as the target time to conduct the confirmatory tests. No survivors were found among the estimated 50,385 and 57,366 treated eggs, which resulted in the efficacy of 99.9941 and 99.9948% mortality (95% CL) at 0 and 2°C, respectively. Our study suggests a technical basis for cold disinfestation on D. suzukii in cage-infested Chinese ‘Red Globe’ (Vitis vinifera L.) grape, which could provide flexible phytosanitary treatment for control of D. suzukii in the international trade of grape.

Ecosystem respiration (ER) is greatly affected by global warming and responds nonlinearly to different warming levels. However, the mechanisms of the response of ER to gradient warming in paddy field remain obscure. Studying the effects and mechanisms of different warming levels on ER and its components in paddy field ecosystems will provide a theoretical basis for predicting future carbon budgets under climate change scenarios. In this study, 2-year gradient warming experiments with 5 warming treatments (+0 °C [control, CK], +0.3 °C [500 W warming, T1], +0.6 °C [1000 W warming, T2], +1.0 °C [1500 W warming, T3], +2.3 °C [3000 W warming, T4]) were performed by using a free air temperature increasing (FATI) system in paddy field in Northeast China. ER and its two components, autotrophic respiration (AR) and heterotrophic respiration (HR), were measured to reveal the mechanisms of the response of ER to gradient warming. The results showed that ER, AR and HR increased significantly under warming treatments and exhibited nonlinear responses to different warming levels. The maximum increases in ER, AR and HR appeared in the 1500 W warming treatment. The nonlinear response of AR was primarily related to total plant biomass (TB), while the nonlinear response of HR was closely related to soil microbial biomass carbon (MBC). Furthermore, warming nonlinearly enhanced the AR/ER ratios but reduced the HR/ER ratios. The AR/ER ratios were much greater than the HR/ER ratios. ER was closely correlated with its two components, and its nonlinear response might mainly derive from that of AR. The results highlight that the nonlinear response patterns of ER and its components to warming should be taken into global carbon cycling models to predict future carbon-climate feedbacks.

The characteristic clogging structures of granular spheres blocking three-dimensional granular flow through hopper outlet are analyzed based on packing structures reconstructed using magnetic resonance imaging techniques. Spheres in clogging structures are arranged in a way with typical features of load-bearing, such as more contacting bonds close to the horizontal plane and more mutually-stabilized contact configurations than packing structures away from the orifice. The requirement of load-bearing inevitably leads to the cooperativity of clogging structures with a correlation length of several particle diameters. This correlation length being comparable with the orifice diameter suggests that a clogging structure is composed of several mutually-stabilized structural motifs to span the orifice perimeter, instead of a collection of independent individual spheres to cover the whole orifice area. Accordingly, we propose a simple geometric model to explain the unexpected linear dependence of the average size of three-dimensional clogging structures on orifice diameter.

In the teleoperation of lunar surface sampling, a four axis robotic arm is adopted to collect lunar soils and transfer them to the sealed pot. Due to the flexibility of slender sampling arm and interval error of the joint, it is difficult to control the end-effector aligned with the mouth of the sealed pot without any feedback. In order to handle this problem, this paper proposes a method to calculate the position and normal orientation of sealed pot with respect to end-effector by using the elliptic features obtained from the monocular vision camera, based on which the angle of each arm joint is to be solved. Due to the rotational symmetry of round sealed pot, it is difficult to determine the rotations of the normal of the sealed pot. Nevertheless, considering special configuration constraints of the robotic arm, we can ignore the influence of undetermined rotation and solve the four joint angles uniquely. Thus, error of joint angles could be corrected and an effective control is exerted to the arm to guide the end effector gradually approaching the sealed pot. Finally, the effectiveness of the method is verified by experiments.

A lot of research has been undertaken on the relationship between exchange rate fluctuation and export. On this basis, this paper considers the moderating effect of financial marketization on the relationship between them, and shifts the research perspective to the provincial level. Using quarterly inter-provincial panel data from 2006 to 2017, this paper focuses on whether financial marketization can weaken the negative effect of exchange rate volatility on export. The conclusions are as follows: at the national level, the depreciation of the inter provincial effective exchange rate in the current period can promote export growth in the next period, while exchange rate volatility will inhibit the next period exports. Financial marketization can mitigate the negative effect of exchange rate volatility on exports. We do however find regional differences in the intensity of these relationships. This study provides empirical evidence for accelerating the reform of financial marketization, steadily promoting the formation mechanism of RMB exchange rate and balancing the development of regional trade.

We report a novel fabrication of nickel-molybdenum alloy nanorods catalyst for hydrogen evolution reaction (HER), which is prepared by co-deposition of pure nickel and molybdenum in a multisource sputtering system on the surface of Ni foam substrate. The Ni–Mo alloy film exhibits favorable vertical nanorods structure and presents the most efficient activity for HER compared to the film only including one metal element. The remarkably enhanced catalytic activity is attributed to its ordered array geometry as well as the synergistic interaction between Ni and Mo. Meanwhile, the open space within nanorod arrays facilitates the electrolyte penetration and diffusion of ionic species, allowing high utilization efficiency of active species as well as rapidly release of evolved hydrogen gas from the electrode surface.

Background: Invasive growth of fibroblast cells, which is regulated by multiple biological factors, is the key event in the pathophysiology of keloid scars. Recent studies have suggested that botulinum toxin type A (BoNT-A) could inhibit invasive growth of keloids. However, the molecular mechanisms are unknown. Objective: The authors explore the effect of BoNT-A on the expression of genes relevant to invasive growth in keloid fibroblasts. Methods: With 112 genes that were relevant to invasive growth, the authors utilized microarray analysis to study messenger RNA expression profiles in keloid fibroblasts treated with BoNT-A. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to confirm the microarray results. Results: Analyses from microarray and qRT-PCR revealed that the S100A4 gene was upregulated and that the TGF-β1, VEGF, MMP-1 , and PDGFA genes were downregulated in fibroblasts treated with BoNT-A. Conclusions: The BoNT-A altered expression levels of S100A4, TGF-β1, VEGF, MMP-1 , and PDGFA genes in keloid fibroblasts provide a useful clue for exploring the function of BoNT-A and finding a novel treatment for keloid scarring.

Forest water conservation as an important ecosystem function has caused a rising interests in the scientific community in recent years.However,there remain some arguments in several aspects regarding the forest water conservation function.For the concept of the forest water conservation,there is no clear definition about its connotation.Another concern is the scaling issue.It is a challenge to scale up the estimation for the forest water conservation from the plot scale to larger scale,e.g.,watershed scale or regional scale.Many quantification methods have been developed,but their suitability,performance,advantages and disadvantages are unknown.Many of such argument issues are significant limits of the forest water conservation in science and management.On the basis of the literature review,we clarify the important role of the water conservation in forest ecosystem function.We also summarize and analyze the concepts of the forest water conservation and its multi-scale connotation,processes and quantification methods.On the spatial scale,function of the forest in mitigating peak flow is effective at a smaller scale but not necessarily at a larger scale.More groundwater recharges into stream flow when forest soil infiltration exceeds evapotranspiration,thus increasing stream flow in the dry season.During a rainfall event,forest water conservation has different features at different temporal scales.For example,the amount of the forest conservation during a rainfall event dominates by the forest canopy interception and most water is stored in the forest due to less evapotranspiration in the rainfall event scale.At the longer temporal scale,the forest water conservation can be determined by the forest canopy interception subtracting evapotranspiration.The functional roles of the forest water conservation at longer temporal scale dominate by purifying water from natural rainfall and mitigating seasonal flow peaks of the river discharges.Most previous studies of the forest water conservation focused on water storage function at the plot scale,but lack better understanding in the forest water conservation function at the watershed or regional scales.We suggest the approach that combines downscaling from the regional to watershed scales and upscaling from the hillside to the watershed scales can an effective way of the scale extrapolation.This idea can be used to address the heterogeneity issue of the forest water conservation function at different spatio-temporal scales.Among the existing quantification approaches of the forest water conservation function,each one highly relies on the temporal and spatial scales and its application goal.An appropriate calculation method should be carefully evaluated and considered based on the objectives,data availability,temporal and spatial scales of each study case.The suitability difference in different calculation methods of the forest water conservation demonstrates the complexity and importance of the multi-scale consideration in forest hydrological processes.In the context of the long-term debates about the relationship between the forest and water,we figure out a few confusing points in the current studies of the forest water conservation function.We also propose the critical scientific questions that should be addressed and a few directions in future studies of forest water conservation function including: 1) to clearly define the connotation and boundary of the forest water conservation function,and develop innovatory methods for determining the forest water conservation function;2) to pay more attentions on the forest water conservation function studies associated with the different spatial and temporal scales,including evaluation of the spatio-temporal variations in forest water conservation function,the scaling effects on estimation of the water conservation function,the trade-off relationship between the upstream forest water conservation and the downstream ecological water need,and the development of the innovatory ways of forest water conservation practices.

Autonomous rendezvous and robotic capturing of flying targets is widely used in many space shuttle missions and it is very crucial for on-orbit service. To perform this task, tracking and pose estimation of the flying targets is usually considered as one of the most important issues, needing to be addressed among the whole process. Taking account of the specificity of space environment such as lighting and the continuity of the rendezvous process, in this paper, we design a fast tracking and accurate pose estimation algorithm for cooperative luminaries (or retro-reflectors), to guide a safe and reliable capturing operation. Different from available target tracking or searching method, this paper defines a new comparability measure function for target appearance and utilizes the continuity of target moving to limit the target search in a predicted range of the image, which accelerates the search process. Meanwhile, the projective shape changes of each luminary due to rotation are also considered to help improve the accuracy of the target extraction. With the positions of multiple target spots obtained from the image, least square method is applied to adjust the spatial pose results iteratively, and finally accurate pose estimation is achieved. Experiments on the simulated space target, which consists of six LEDs, validate the proposed method.

Positioning rovers with a large distance is an important mission of the ground tele-operation center, which can decrease or eliminate the position errors accumulated in continuous measurement and multiple calculations, and facilitate the rover to arrive at faraway scientific probing targets. Currently, the most representative high-accuracy positioning methods are implemented with multi-camera photogrammetric model, which takes the homonymous point pairs extracted from images as constraint points of camera bundles to establish observation equations. The amount, spatial distribution and matching accuracy of homonymous point pairs will affect the effectiveness and accuracy of rover positioning. However, in the case of long-range moving, the images acquired by rover in two positions with a fairly big distance are difficult to match due to existence of large scale and rotation transformations, reflected view of the same scenery and different illumination conditions between acquired images, and a lot of outliers will be generated. In this paper, we introduce projective transformations, which are approximately calculated with imaging relations of two positions, to tackle the outlier elimination problem, and design an iterative algorithm to reduce the outliers and refine the positioning results simultaneously. With this method, the initial approximate positioning information of the rover can be utilized to constrain the range of each feature point projected to another image, and outliers are reduced gradually, preserving almost all the inliers. Finally, several experiments are conducted with lunar surface images acquired by Chang'E-3 rover, which witness the validity of the proposed method.

Desertification in the karst mountain regions of southwest China is one of the most challenging environmental issues in western China because of its severe negative effects on the local community.Based on natural and cultural factors that cause rocky desertification occurrence and development,a simple,effective simulation and prediction model for karst rocky desertification was constructed to gain an improved understanding of the process and mechanism of rocky desertification development(KrastCA).This model effectively incorporated ecological processes,including plant colonization,plant mortality,land degradation,and soil formation with the local facilitation of the plant.The random cellular automata model,which can generate complex spatial patterns via simple rules,was employed to make state transition between vegetation,bare soil,and rock in a certain probability.Combined with the remote sensing(RS) and geographic information system(GIS) technology,rural settlements were extracted from TM image,and vegetation-bare soil-rock composition abundance images using the linear spectral unmixing approach,which is the initial state of the KrastCA model.The typical karst areas in Guanling County were selected as the study areas.KarstCA model simulation results performed better forecast(73.4% accuracy) when natural and human factors were considered compared with incorporating only natural factors(56.7% accuracy).This outcome suggests that the model used in this study effectively incorporated the key ecological processes that affected rocky desertification occurrence and development.By considering both natural and human factors and natural factor alone,KrastCA model indicated that spatial distribution differences in rocky desertification mainly focused on the center and north of the study area in 2007,which mainly depended on the intensity and scales of human activities.The land cover(vegetation,bare soil,and rock) in karst regions showed nonlinearity during 1992 to 2007(16 years).The trend of vegetation covering ≥ 54% showed a significantly negative correlation with rocky areas(P0.01).This finding strengthens the importance of vegetation in combating rocky desertification.Human activities hampered the development of rocky desertification in the study area during the simulation period.To some extent,the positive effects of human activities(e.g afforestation) and the negative effects(e.g deforestation,overgrazing,etc.) partially counteracted the dramatic changes in the vegetation area.However,the landscape tended to fragmentize.This study attempted to couple the surface process model into the cellular automata model,breaking through the previous study modeling surface process only by the state transition probability,and lack of understanding its mechanism.In addition,this study took into account the complexity of natural and human drivers in different spatial scales to act on the rocky desertification.The findings of this study shed light on the effects and contributions of these factors on surface processes.

This paper aimed at analyzing the reasons of dying out of the local cultural in domestic cities, especially in boom cities. It mainly discusses and puts forward pattern to build city cultural characteristics that meets request of the times humanly.

$����\to ��_t^0$ is the major production mechanism of neutral top-pion at the linear colliders. In this paper, we calculate the cross section of the process $����\to ��^0_t$ and discuss the potential to observe the neutral top-pion via its various decay modes at the planned ILC. The study show that, among the various neutral top-pion production processes at the linear colliders, the cross section of $����\to ��_t^0$ is the largest one which can reach the level of $10^1-10^2$ fb. Due to the existence of the tree-level flavor-changing coupling $��_t^0 t\bar{c}$, $����\to ��_t^0 \to t\bar{c}$ can provide enough number of typical signals to identify the neutral top-pion with the clean SM background. Therefore, the process $����\to ��_t^0$ play an important role in searching for the neutral top-pion and test the TC2 model., 16 pages, 5 figures

Molecular engineering of intra- and interchain interactions transforms polymers into good heat conductors., Traditional polymers are both electrically and thermally insulating. The development of electrically conductive polymers has led to novel applications such as flexible displays, solar cells, and wearable biosensors. As in the case of electrically conductive polymers, the development of polymers with high thermal conductivity would open up a range of applications in next-generation electronic, optoelectronic, and energy devices. Current research has so far been limited to engineering polymers either by strong intramolecular interactions, which enable efficient phonon transport along the polymer chains, or by strong intermolecular interactions, which enable efficient phonon transport between the polymer chains. However, it has not been possible until now to engineer both interactions simultaneously. We report the first realization of high thermal conductivity in the thin film of a conjugated polymer, poly(3-hexylthiophene), via bottom-up oxidative chemical vapor deposition (oCVD), taking advantage of both strong C=C covalent bonding along the extended polymer chain and strong π-π stacking noncovalent interactions between chains. We confirm the presence of both types of interactions by systematic structural characterization, achieving a near–room temperature thermal conductivity of 2.2 W/m·K, which is 10 times higher than that of conventional polymers. With the solvent-free oCVD technique, it is now possible to grow polymer films conformally on a variety of substrates as lightweight, flexible heat conductors that are also electrically insulating and resistant to corrosion.

Air-stable, lightweight, and electrically conductive polymers are highly desired as the electrodes for next-generation electronic devices. However, the low electrical conductivity and low carrier mobility of polymers are the key bottlenecks that limit their adoption.We demonstrate that the key to addressing these limitations is tomolecularly engineer the crystallization and morphology of polymers. We use oxidative chemical vapor deposition (oCVD) and hydrobromic acid treatment as an effective tool to achieve such engineering for conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT). We demonstrate PEDOT thin filmswith a record-high electrical conductivity of 6259 S/cm and a remarkably high carriermobility of 18.45 cm2V-1s-1by inducing a crystallite-configuration transition using oCVD. Subsequent theoretical modeling reveals a metallic nature and an effective reduction of the carrier transport energy barrier between crystallized domains in these thin films. To validate this metallic nature, we successfully fabricate PEDOT-Si Schottky diode arrays operating at 13.56MHzfor radio frequency identification (RFID) readers, demonstratingwafer-scale fabrication compatible with conventional complementary metal-oxide semiconductor (CMOS) technology. The oCVD PEDOT thin films with ultrahigh electrical conductivity and high carrier mobility show great promise for novel high-speed organic electronics with low energy consumption and better charge carrier transport., National Science Foundation (U.S.) (grant DMR-1231319), United States. Air Force. Office of Scientific Research, Failure Testing Service, Multidisciplinary Research Program of the University Research Initiative ((grant no. FA9550-15-1-0514), United States. Department of Energy. Office of Basic Energy Science (award no. DE-SC0001088 (MIT)), United States. Department of Energy. Office of Basic Energy Science (award no. DE-SC0001299), Samsung Scholarship Program, National Science Foundation (U.S.). Materials Research Science and Engineering Centers (Program) (DMR-1719875)