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The roles of plant-specific transcription factor family YABBY may vary among different members. OsYABBY6 is a rice YABBY gene, whose function is not well elucidated so far. In this paper, we show that OsYABBY6 is a nucleus-localized protein with transcriptional activation activity. OsYABBY6 is predominantly expressed in the palea and lemma, as well as in the sheath, culm and node. OsYABBY6 RNA interference (RNAi) plants exhibited altered plant height and larger grain size. Under cold treatment, OsYABBY6 overexpression (OE) plants had up-regulated expression of cold responsive genes, and accumulated less reactive oxygen species but more proline compared to wild type, resulting in improved cold tolerance. On the other hand, RNAi plants showed enhanced drought tolerance compared to the wild type by slower water loss, less reactive oxygen species but more proline and soluble sugar accumulation. In addition, endogenous abscisic acid (ABA) level was reduced in OsYABBY6 RNAi plants, and RNAi and OE plants were more and less sensitive to ABA treatment, respectively. Accordingly, we deduce that OsYABBY6 positively regulates cold response but negatively regulates drought response through different pathways. Our study reveals the crucial roles of OsYABBY6 in plant architecture and grain development, as well as in abiotic stress response, providing new insights into the functions of YABBYs in rice. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study was to construct and validate a nomogram to predict the 1-, 3- and 5-year overall survival (OS) in external ear melanoma (EEM) patients in the elderly based on the Surveillance, Epidemiology, and End Results (SEER) database. Methods: The information of patients diagnosed with EEM in the elderly between 2010 and 2014 was downloaded from the SEER database. Univariable and multivariable Cox analyses were carried out to identify the independent characteristics, and the independent factors were further included to construct a nomogram. The discriminative ability and calibration of the nomogram to predict OS were tested using C-index value, and calibration plots. Based on the risk score of the nomogram, the patients were divided into high- and low-risk subgroup. Finally, the survival differences of different subgroups were explored by Kaplan–Meier curves. All statistical analyses were performed by R 4.2.0. Results: A total of 710 elderly EMM patients were included and randomly divided into training cohort and validation cohort. Univariable Cox regression were used to identify age, race, sex, American Joint Committee on Cancer (AJCC), T, surgery, radiation, chemotherapy, and tumor size as independent risk factors. Then, multivariable Cox model to determine significant risk factors was used to establish the selected factors. A nomogram for predicting the 1-, 3- and 5-year OS was constructed using the independent variables including age, AJCC, T, surgery and chemotherapy. The C-index values were 0.78 (95% CI 0.75–0.81) in training set and 0.72 (95% CI 0.66–0.78) in validation set. The calibration curves were closer to ideal curves indicated the accurate predictive ability of this nomogram. The elderly patients with EEM in the low-risk group showed a longer OS than patients in the high-risk group in both training and validation cohorts. Conclusions: Our study established and validated a novel model to predict 1-, 3- and 5-year OS for EEM. The individualized nomogram has a good prognostic ability and can be used as a new survival prediction tool for the elderly patients with EMM. [ABSTRACT FROM AUTHOR]

Ischemic heart disease (IHD) is the leading cause of death and emergency department (ED) admission. We aimed to develop more accurate and straightforward scoring models to optimize the triaging of IHD patients in ED. This was a retrospective study based on the MIMIC-IV database. Scoring models were established by AutoScore formwork based on machine learning algorithm. The predictive power was measured by the area under the curve in the receiver operating characteristic analysis, with the prediction of intensive care unit (ICU) stay, 3d-death, 7d-death, and 30d-death after emergency admission. A total of 8381 IHD patients were included (median patient age, 71 years, 95% CI 62–81; 3035 [36%] female), in which 5867 episodes were randomly assigned to the training set, 838 to validation set, and 1676 to testing set. In total cohort, there were 2551 (30%) patients transferred into ICU; the mortality rates were 1% at 3 days, 3% at 7 days, and 7% at 30 days. In the testing cohort, the areas under the curve of scoring models for shorter and longer term outcomes prediction were 0.7551 (95% CI 0.7297–0.7805) for ICU stay, 0.7856 (95% CI 0.7166–0.8545) for 3d-death, 0.7371 (95% CI 0.6665–0.8077) for 7d-death, and 0.7407 (95% CI 0.6972–0.7842) for 30d-death. This newly accurate and parsimonious scoring models present good discriminative performance for predicting the possibility of transferring to ICU, 3d-death, 7d-death, and 30d-death in IHD patients visiting ED. [ABSTRACT FROM AUTHOR]

The environmental standards of soil and sludge have been typically referenced for freshwater sediment determination and quality assessment, especially in some areas without sediment standards. The feasibility of determination method and quality standard of soils and sludge for freshwater sediment was investigated in this study. Fractions of heavy metals, nitrogen, phosphorus, and reduced inorganic sulfur (RIS) in different type of samples were determined, including freshwater sediments, dryland and paddy soils, and sludge with air-drying (AD) and freeze-drying (FD) treatment, respectively. Results showed fraction distributions of heavy metals, nitrogen, phosphorus, and RIS in sediments markedly differed from those of soils and sludge. Fraction redistributions of heavy metals, nitrogen, phosphorus, and RIS in sediments were observed with AD compared to those treated by FD. The proportions of heavy metals, nitrogen, and phosphorus associated with organic matter (or sulfide) in FD sediments decreased by 4.8–74.2%, 9.5–37.5%, and 16.1–76.3%, respectively, compared to those in AD sediments, while those associated with Fe/Mn oxides increased by 6.3–39.1%, 50.9–226.9%, and 6.1–31.0%, respectively. The fraction proportions of RIS in sediments with AD also sharply decreased. Determination of standard methods for sludge and soil caused the distortion of pollutant fraction analysis in sediment. Similarly, the quality standard of sludge and soil was inappropriate for sediment quality assessment due to the differences in pollutant fraction pattern between sediment and soils/sludge. Totally, soil and sludge standards are inapplicable for freshwater sediment pollutant determination and quality judgment. This study would greatly advance the establishment of freshwater sediment determination methods and quality standards. [ABSTRACT FROM AUTHOR]

In this study, the effects of redox conditions, nitrogen (NH4+–N and NO3−–N) and phosphate in the overlying water on the release of arsenic (As) in coastal sediments were investigated. The results indicated that the release of As under anaerobic conditions presented a release—dynamic equilibrium pattern. The reduction of arsenate (As(V)) to arsenite (As(III)) under anaerobic conditions was the main factor promoting the release of As. The reductive dissolution of Fe(III) oxides contributed very limited to the release; the release–remove–release pattern was observed under aerobic conditions. Although Fe(III) oxides has strong adsorption capacity for As, sulfide oxidation may be a source of As, which may continuously release As under aerobic conditions. In addition, low concentration (< 6 mg L−1) of nitrogen may stimulate anaerobic metabolism of microorganisms, resulting in reduction and dissolution of As. The low pH of high concentration (> 6 mg L−1) of nitrogen may affect the microbial community and thus decreased the concentration of As. Since the reduction of Fe(III) oxides decreased the adsorption sites, the competitive adsorption of phosphate had no significant effect on the release of As under anaerobic conditions. Totally, this study provides a new understanding of the behavior of As in coastal sediments under variable environments. [ABSTRACT FROM AUTHOR]

In this study, the impacts of dissolved oxygen (DO) on dynamics concentrations of heavy metals (Cu, Cd, Cr, and Pb) from estuary sediments were investigated in a 49-day laboratory simulation. The exchange flux method, Bureau Communautaire de Référence (BCR) sequential extraction procedure, and risk assessment code (RAC) were used to analyze the behavior of heavy metals. The results indicated that oxic environments promoted the concentrations of Cu and Cd in overlying water compared to the anoxic environments. The exchange fluxes showed that the diffusion of Cu, Cd, Cr, and Pb from sediments was the predominant process in the first 9 days, and a metastable equilibrium state was gradually reached in the later period under anoxic conditions. However, oxic conditions extended the time required to reach metastable equilibrium for Cu over the sediment–water (overlying water) interface (SWI). Although the reducible fractions of Cu, Cd, and Pb accounted for a large proportion of their total levels, the release ability of Cu, Cd, and Pb was limited by the high content of sulfide under anoxic conditions. The RAC values indicated that anoxic environments increased the proportion of acid-soluble fraction. The information obtained from this study highlights the potential risk for re-release of heavy metal from sediments under different redox conditions. [ABSTRACT FROM AUTHOR]

As an enabling technology for dynamic spectrum access (DSA), cognitive radio (CR) is widely regarded as one of the most promising technologies for future the fifth generation (5G) wireless communications. Although there have been significant prior researches to combat interference on primary users (PUs), the problem of mitigating mutual interference between secondary users (SUs), -which is tightly coupled with SU's spectrum leasing- is still not understood well. This paper proposes a DSA algorithm based on game theory, which jointly performs spectrum leasing and interference mitigation among SUs. The problem is modeled as an oligopolistic competition using Stackelberg model. We have carefully studied the SU's spectrum utilization behavior with respect to various criteria of the proposed game theoretic model. Simulation results shows that, Compared with Cournot game model, the proposed scheme enables SUs to efficiently utilize the licensed spectrum shared with PUs in a dynamic environment while maximizing the spectrum utilization. [ABSTRACT FROM AUTHOR]

The crude enzyme (PH- 1) isolated from Pseudostellaria heterophylla by our group has catalyzed enzymatic cyclization of linear peptide NH2-Gly1-Gly2-Leu-Pro-Pro-Pro-Ile-Phe-COOH ( 4) into cyclopeptide heterophyllin B (HB) from plant for the first time. To ensure this reaction, some analytical methods including TLC, HPLC, MS, NMR, and 3C labeling were used to prove that the reaction of substrate 4 sharing residue of NH-Phe-Gly-CO was successful. [ABSTRACT FROM AUTHOR]

In recent years, topics related to robotics have become one of the researching fields. In the meantime, intelligent mobile robots have great acceptance, but the control and navigation of these devices are very difficult, and the lack of dealing with fixed obstacles and avoiding them, due to safe and secure routing, is the basic requirement of these systems. In this paper, the modified artificial potential field (APF) method is proposed for that robot avoids collision with fixed obstacles and reaches the target in an optimal path; using this algorithm, the robot can run to the target in optimal environments without any problems by avoiding obstacles, and also using this algorithm, unlike the APF algorithm, the robot does not get stuck in the local minimum. We are looking for an appropriate cost function, with restrictions that we have, and the goal is to avoid obstacles, achieve the target, and do not stop the robot in local minimum. The previous method, APF algorithm, has advantages, such as the use of a simple math model, which is easy to understand and implement. However, this algorithm has many drawbacks; the major drawback of this problem is at the local minimum and the inaccessibility of the target when the obstacles are in the vicinity of the target. Therefore, in order to obtain a better result and to improve the shortcomings of the APF algorithm, this algorithm needs to be improved. Here, the obstacle avoidance planning algorithm is proposed based on the improvement of the artificial potential field algorithm to solve this local minimum problem. In the end, simulation results are evaluated using MATLAB software. The simulation results show that the proposed method is superior to the existing solution. [ABSTRACT FROM AUTHOR]

A parallel unstructured mesh generation technique is proposed based on the built-in cyber-physical system (CPS) of Parallel Virtual Machine context. A static load-balancing strategy for computational domain decomposition is firstly presented in the paper. After dividing the whole computational domain into several sub-domains, unstructured grids are separately generated in each sub-domain using the advancing-front grid generation technique. Besides, for a dynamic load-balancing strategy, Lohner's advancing front domain-splitting algorithm is improved to make the sub-grids and their boundaries more favorable for the grid generation. Moreover, a new optimization strategy of sub-domain's boundary is simultaneously presented to smooth the boundaries and improve the quality of grids. Finally, conditions of receiving new points and elements are also developed during the grid generation in the sub-domain. Meanwhile, a new strategy of receiving new elements and refusing new points during the interface grid generation is proposed, which can save computational cost. A new parallel Laplacian smoother technique is implemented to generate high-quality mesh. Meshes for NACA0012 airfoil, cylinder, and multi-element airfoil are generated by the improved parallel algorithm using the static and dynamic load-balancing strategies. Some comparisons of parallel calculations are also made using the different number of processors in the tables. [ABSTRACT FROM AUTHOR]