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High temperatures cause physiological and biochemical changes and significantly affect young panicle development of rice (Oryza sativa L.). Brassinosteroids play important roles in enhancing crop stress resistance. In this study, we subjected rice cultivars Huanghuazhan (heat-resistant) and IR36 (heat-sensitive) to high temperature (HT, 40 ºC) or normal temperature (NT, 33 ºC) for 7 d at the panicle initiation stage, in conjunction with application of 24-epibrassinolide [EBR, a synthetic brassinolide (BR)] or brassinazole (BRZ, a BR biosynthesis inhibitor) at the beginning of the treatments. HT exacerbated spikelet degeneration and inhibited young panicle growth, which were partially prevented by EBR application, while BRZ application aggravated the reduction in spikelet number. HT decreased the contents of BR, active cytokinins (aCTK), active gibberellins (aGA) and indole-3-acetic acid (IAA), but increased the content of abscisic acid (ABA) in young panicles. The activities of key enzymes involved in sucrose hydrolysis, glycolysis and the tricarboxylic acid cycle in young panicles were decreased with the change of endogenous hormone levels under HT. In addition, the contents of H 2 O 2 and malondialdehyde (MDA) were increased and the activities of antioxidant enzymes were decreased in young panicles. Exogenous application of EBR induced the expression of phytohormone biosynthesis-related genes and down-regulated the expression of phytohormone catabolism-related genes to increase the contents of endogenous BR, aCTK, aGA and ABA, thus promoting the decomposition and utilization of sucrose in young panicles, enhancing the activities of superoxide dismutase, catalase and peroxidase, and reducing the accumulation of H 2 O 2 and MDA in young panicles, whereas application of BRZ had the opposite physiological effects. These results showed that brassinosteroids mediate endogenous phytohormone metabolism to alleviate HT injury at the panicle initiation stage in rice. [ABSTRACT FROM AUTHOR]

In recent years, the number of shut-down wells in China's Changqing Gas Field has been increasing at a rate of 3% of the total number of wells every year, which seriously affects the stable production of natural gas in the gas field. Among them, the number of shut-down gas wells caused by reservoir damage is the largest, which seriously affects the productivity of gas wells. In this paper, the damage mechanism of the reservoir is clarified on the basis of the systematic evaluation of the geological characteristics of the cores of the lower Paleozoic tight sandstone reservoir in Changqing Oilfield. The research results show that in the early stage of well construction, the lower Paleozoic reservoir cores have weak high temperature and high pressure flow velocity sensitivity, acid sensitivity and alkali sensitivity damage. For moderate-to-strong high-temperature and high-pressure water-sensitive damage and moderate-to-weak high-temperature and high-pressure salt-sensitive damage, the salinity of the fluid entering the well should be guaranteed to be 40323.5 mg/L ~ 69126 mg/L. It can avoid too high or too low mineralization to cause clay minerals to hydrate, disperse or fall off, block small throats and micro-fractures, and then reduce reservoir permeability. In addition, the Paleozoic reservoir cores in the study area have strong stress-sensitive damage. Therefore, with the gradual increase of the production time, the decrease of the reservoir pressure and the decrease of the production pressure difference will further aggravate the stress damage of the reservoir, and finally cause the rapid decrease of the reservoir permeability and gas production in the near-wellbore zone. [ABSTRACT FROM AUTHOR]

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Exploring the effects of straw return (ST) and potassium fertilizer on soil structure, spring maize (Zea mays L.) root growth, K-absorption efficiency and yield is essential for devising optimized straw return and potassium fertilizer management practices to increase grain yield for food security. In this study, two straw return levels used were straw return, no straw return and two potassium application levels used were 6K (90 kg/ha potassium application), no potassium (0K). Analyzed the effects of the above four treatments on soil structure, spring maize root indicators, K-absorption efficiency and yield in three ecological regions in two years. The results showed that the effect of straw return on soil structure and root growth was better than that of applying potassium fertilizer. The effect of potassium fertilizer application on maize grain yield and K-absorption efficiency was better than that of straw return. The impact of the interaction was better than straw return or the application potassium fertilizer alone. Straw return improved the effects of potassium fertilizer on soil bulk density, soil porosity, spring maize root length, root surface area, root volume, maize grain K-absorption efficiency and yield by 3.99%-7.27%, 3.89%-7.40%, 1.35%-71.01%, 19.16%-42.45%, 10.49%-22.73%, 13.57%-19.67% and 4.43%-7.05%, respectively. Therefore, the interaction of straw return and potassium fertilizer was the best measure to maintain high and stable maize yield, increasing K-absorption efficiency and improving the nutrient resource management of straw and potassium fertilizer, which was appropriate for spring maize planting. [ABSTRACT FROM AUTHOR]

How to allocate heat resources during yield formation and grains drying in the field to ensure food security while reducing the grain moisture content (GMC) is an important issue in maize (Zea mays L.) production in China. In this study, we established three production scenarios (traditional production (TPS, GMC > 30% at harvest), mid-moisture grain harvest (MMHS, GMC ≤ 25% at harvest), and low-moisture grain harvest (LMHS, GMC ≤ 20% at harvest)). Five varieties (DMY1, FK139, DK159, XY335, and JK968) were selected as model varieties to establish a grain drying prediction model, and the model prediction accuracy was good (RMSE = 2.96-4.04%, R² = .408-.733). Results revealed that the production loss of the LMHS was 23.7% compared to the TPS, while the MMHS had a production loss of 6.5%. By replacing new varieties with high yield potential and fast grain drying rate, even small production increases can be achieved in MMHS. By adjusting the layout, it was possible to achieve 25% GMC in Inner Mongolia, which can promote the mechanical grain harvesting. However, the conditions for further reducing GMC (20%) at harvest are not yet available, and this requires more detailed future research. [ABSTRACT FROM AUTHOR]

MicroRNAs are a class of short non-coding RNAs that contain approximately 22 nucleotides and play a regulatory role in RNA silencing and translational repression. miR-92 belongs to the miR-17-92 family and has a regulatory effect on cell proliferation, apoptosis, and expression of proto-oncogenes and tumor suppressor genes. However, its function in flatfish is unclear. In this study, we used farmed Japanese flounder, Paralichthys olivaceus, and showed that gata5 is a target gene of miR-92. Experiments on miR-92 overexpression indicated that gata5 and sox17 were downregulated, while the transcription level of ntl increased. By contrast, depletion of miR-92 resulted in increased gata5 and sox17 levels and reduced ntl level. Moreover, thiourea treatment indicated that miR-92 may inhibit the metamorphic development of Japanese flounder. Our study suggests that miR-92 regulates the fate of endoderm and mesoderm by controlling gata5. [ABSTRACT FROM AUTHOR]

With the increasing population and livestock volume, the blindness of herdsmen in using grassland resources has become an important factor causing grassland degradation and affecting the ecological environment. Reasonable utilization of pasture can improve the efficiency of configuring grassland resources and maintain ecological sustainable development. This paper determines the nomadic routes of multi-herdsmen through multi-agent nomadic network model. Firstly, a nomadic network is established, in which the target grassland is determined by the Normalized Difference Vegetation Index. Then, the Maximum Flow Model is designed to limit the Carrying Capacity of the entire nomadic network. Next, the paths for herdsmen are acquired on the basis of the shortest total path length of all livestock. Finally, the feasible routes are achieved by using the LINGO program. The result shows that the model is valid, and the multi-agent nomadic route model proposed in this paper has more advantages than random selection of nomadic route, which can be used as a reference for herdsmen to graze. [ABSTRACT FROM AUTHOR]

In this study, we investigate whether consumers with different cultures concentrate on different product features in online consumer product reviews and show different opinions toward individual product features of the same products. To this end, we extract product features and their associated opinions (i.e., feature-opinion pairs) from online consumer reviews of the same products available at Amazon websites for U.S. and Chinese consumers. The analysis of 4,754 reviews shows that American consumers tend to focus more on usability features of products and have more negative opinions on the same product features in their online reviews than Chinese consumers. Chinese consumers, on the other hand, comment more on aesthetics of products in their reviews. These findings provide some valuable guidance for sellers and manufacturers to better customize their products and improve marketing strategies for consumers with different cultural backgrounds. [ABSTRACT FROM AUTHOR]

The high-risk nodes are helpful for the management firms to develop risk mitigation measures and reallocate their resources to create a safe environmental condition for Pedestrians. Urban public security is a major content of state building. With constantly accelerated urbanization process in China, the life and property security of central business district (CBD), which serves as the main object of study of urban public security, increasingly aggravates. As an important constituent part of the external space of CBD, the pedestrian space has high crowd intensity and many potential safety hazard, which is a key and difficult point of emergency evacuation. Based on the current situation of the emergency evacuation for pedestrian space in three Chongqing CBDs, an analysis is conducted into the characteristics of the work and the necessity of innovation. Difficulties in the innovation process of the emergency evacuation are discussed in combination of the relevant living examples, and related optimizing strategies are proposed to realize the innovation and development of the work. [ABSTRACT FROM AUTHOR]

Interest in the development of metal removal by biosorption using microorganisms is evident in the recent literature, and the ability of microbial biomass to accumulate and remove heavy metals from water has been widely reported. We screened strains of bacteria for growth in a medium containing 10 mM of Ni(I). The optimum growth conditions of the bacteria were as follows: growth temperature 35°C, pH 7, and ventilation of 60 ml. The bacterium can also grow in media with Zn and Cd. With increasing metal ion concentration, there was a corresponding increase in inhibition of the culture. The inhibitory cadmium ions are larger than zinc ions. The optimal conditions for nickel removal were determined as pH 8 and a temperature of 30°C; the optimal dosage of bacteria powder is 3 g/L. A bacterial strain was isolated from the wastewater of a local factory for its potential biosorption of nickel (Ni). This study validates that bacterium Ni could be used as an inexpensive and highly efficient biosorption agent for the removal of heavy metals from aqueous environment. [ABSTRACT FROM AUTHOR]

The gradual increase in the output of China's online literature industry and strengthening of the copyright development chain has yet to result in any standardization of copyright management. This article provides an analysis of discrimination against online literature writers, as their writing is usually considered less creative than conventionally published work. This paper then analyses the rampant piracy and plagiarism plaguing online literature in China and the difficulty authors encounter in protecting their rights. After examining this environment, the article discusses the reasons behind the dysfunctional copyright ecology facing online literature writers. It focuses on the position of the online literature platform, namely the potential capital advantage of the platform and associated weakening of the 'elite' label applied to certain online literature writers following from the freemium business model. Unclear management from the government is also addressed. [ABSTRACT FROM AUTHOR]

Na2Fe0.5Mn0.5PO4F as a cathode material for Na ion batteries is synthesized by a solid-state method. Synchrotron based in situ X-ray absorption near edge structure (XANES) and X-ray diffraction (XRD) techniques are used to study the electronic and crystal structure evolutions of Na2Fe0.5Mn0.5PO4F, complemented by electrochemical analyses during the electrochemical sodiation/desodiation. A reversible capacity of 107 mAh/g can be obtained at 12.4 mA/g with two well-defined voltage plateaus centered at 2.9 and 3.5 V vs. Na/Na+. Clear edge shifts in the Fe and Mn K-edge XANES are observed for Na2Fe0.5Mn0.5PO4F at low current density (i.e., 8 mA/g), relating to the two plateaus in the charging curve associated with the Fe2+/Fe3+ and Mn2+/Mn3+ redox reactions sequentially. Increasing the charge current density to 100 mA/g, similar spectroscopic behavior is observed for Fe K-edge XANES. While, the Mn K-edge shift is smaller compared with this observed at 8 mA/g, indicating the sluggish reaction kinetic of Mn3+/Mn2+ redox couple. Continuous diffraction peaks shifts in in-situ XRD patterns of Na2Fe0.5Mn0.5PO4F are observed throughout the charge-discharge process without emergence of new peaks, indicating of solid-solution processes. Na2Fe0.5Mn0.5PO4F shows good structural reversibility during the electrochemical sodiation/desodiation. [ABSTRACT FROM AUTHOR]

Purpose: Accumulating evidence has shown that dysregulation of microRNA-191 (miR-191) is closely associated with tumorigenesis and progression in a wide range of cancers. This study aimed to explore the potential role of miR-191 in esophageal squamous cell carcinoma (ESCC). Materials and Methods: miR-191 expression was assessed in 93 ESCC tissue specimens by real-time polymerase chain reaction, and survival analysis was performed via Kaplan-Meier and Cox regression analyses. 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide, plate colony-forming, BrdU, and Transwell assays were conducted to observe the effect of miR-191 on ESCC proliferation and invasion. Luciferase reporter and western blot assays were taken to identify target genes of miR-191. Results: miR-191 was overexpressed in 93 cases of ESCC, compared with adjacent normal tissues, and miR-191 expression was significantly related to differentiation, depth of invasion, TNM stage, lymph node metastasis, and distant metastasis of tumor. Kaplan-Meier and Cox regression analyses demonstrated that overexpression of miR-191 was an independent and significant predictor of ESCC prognosis. Both gain-of-function and loss-of-function experiments showed that miR-191 promoted ESCC cell proliferation and invasion activities in vitro. Early growth response 1 (EGR1), a tumor suppressor, was predicted as a direct target of miR-191. Luciferase reporter and western blot assays proved that miR-191 reduced EGR1 expression by directly binding its 3' untranslated region. Moreover, EGR1 knockdown by siRNA enhanced ESCC cell growth and invasion. Conclusion: Our findings provide specific biological roles of miR-191 in ESCC survival and progression. Targeting the novel miR-191/EGR1 axis represents a potential new therapeutic way to block ESCC development. [ABSTRACT FROM AUTHOR]

In recent years, data centers have become the core infrastructure to deal with big data processing. For these big data applications, network transmission has become one of the most important factors affecting the performance. In order to improve network utilization and reduce job completion time, in this paper, by real-time monitoring from the application layer, we propose job-aware priority scheduling. Our approach takes the correlations of flows in the same job into account, and flows in the same job are assigned the same priority. Therefore, we expect that flows in the same job finish their transmissions at about the same time, avoiding lagging flows. To achieve load balancing, two approaches (Flow-based and Spray) using ECMP (Equal-Cost multi-path routing) are presented. We implemented our scheme using NS-2 simulator. In our evaluations, we emulate real network environment by setting background traffic, scheduling delay and link failures. The experimental results show that our approach can enhance the Hadoop job execution efficiency of the shuffle stage, significantly reduce the network transmission time of the highest priority job. [ABSTRACT FROM AUTHOR]

This study presents a new method to solve the pose estimation problem of the combined spacecraft translational and rotational motion using twistors. The twistor representation enables the use of the unscented Kalman filter in the proposed pose estimation method to achieve a higher estimation accuracy than can be achieved with the method using a dual-quaternion-based extended Kalman filter. The unscented Kalman fdter is difficult to design using dual quaternions because of the normalization constraint problem. To overcome this problem, the twistor representation in the framework of dual numbers is introduced to describe the spacecraft local pose error, whereas dual quaternions are used to describe the absolute pose. The unscented Kalman filter schemes, each of which uses different measurements, are designed based on the twistor representation. The proposed unscented Kalman filter schemes using twistors are compared with the dual-quaternion-bascd multiplicative extended Kalman filter through simulations. The results demonstrate the effectiveness of the proposed method and indicate that the twistor-based unscented Kalman filter is superior to the dual-quaternion-based multiplicative extended Kalman filter when both the initial estimation errors are large and the observation model is highly nonlinear. [ABSTRACT FROM AUTHOR]

The article presents studies on controller development work as conducted in dual quaternions. A study established a model-independent proportional derivative (PD)-like controller and a coupled relative motion model with the use of dual quaternions aimed with the use of feedback of logarithm of dual quaternion. Another study proposed an attitude tracking controller and a nonlinear adaptive position.

This paper aims to discuss the effect of traditional Chinese medicine preparation Huayu Zhitong powder in the treatment of distal radius fracture. In this paper, 200 patients with distal radius fracture were randomly divided into treatment group and control group. Patients in treatment group orally took Huayu Zhitong powder, while patients in control group were treated with traditional Shangke Jiegu tablets with traditional Chinese medicine composition. After fixed in a cast plaster, patients in the two groups were supervised the disappearance time of pain by adopting NRS (Numerical rating scale) from scale 0 to 10. Besides, they returned at day 5 and day 8 respectively, and then they were observed the swelling affected part. At day 14, day 28, and day 56 after reduction they respectively took an x-ray. Then they would be graded according to the growth of osteotylus and the clinical effects were evaluated based on the grade. Finally, the treatment group worked better in relief effect than the control group. At day 8, the treatment group worked better in detumescence than the control group. At day 28, the recovery effect in treatment group was found to be better than the other. From these, it is shown that the traditional Chinese medicine works much better in the treatment of distal radius fracture than traditional treatment medicine. Thus it is of great worth spreading for use. [ABSTRACT FROM AUTHOR]

In this paper, a new approach is proposed to predict optimal machining conditions for most energy-efficient machining of Ti6Al4 V. First an analytical cutting force model is implemented to predict the cutting forces and cutting power, followed by the temperature prediction to estimate the cutting temperature. Then based on the cutting temperature and stability lobes, the energy-efficient machining conditions are obtained. Thereafter experiments were performed to verify the simulation results by measuring forces with force gauges and cutting temperature using the tool-work thermocouple method. The case study shows that the proposed approach provides more stable cutting conditions as well as longer tool life using optimal cutting conditions by controlling vibration and the cutting temperature. [ABSTRACT FROM AUTHOR]

Low nitrogen use efficiency (NUE) and productivity with excessive use of N fertilizer in maize (Zea mays L.) is a common issue for smallholder farm systems. A 2-yr field study was conducted to assess the impacts of integrated agronomic management strategies (MT) on pre- and post-silking N uptake, dry matter (DM) production dynamics, and their relationships to yield and NUE components. Three MTs were compared with the regional conventional farming practices (FP). We found that biomass yields differed significantly with similar harvest index (HI) among the MT treatments. While OPT-1 produced 21% greater DM but only 4% greater grain yield, OPT-2 had 27% higher yield, and 200% greater NUE, compared to FP. Our results showed the possibility of simultaneously achieving high yield and high NUE with optimized MT. In OPT-2, 13% greater DM production and 12% more N uptake after anthesis contributed 5% more to grain yield and 18% more to grain N. In H Y, excessive N input did not improve the stay-green trait nor did it enhance grain yield. These results imply a better balance between improving total biomass and achieving more DM accumulation in the post-silking period with gradually optimized agronomic management practices than other MT. The enhanced NUE observed in OPT-2 primarily originated from the improved N recovery efficiency, which was associated with larger root biomass at silking and greater post-silking N uptake. Further NUE improvement in maize could be anticipated through enhanced N internal efficiency by balancing DM and N accumulation between vegetative and reproductive periods. [ABSTRACT FROM AUTHOR]

Abstract: Reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) is a technique widely used for quantification of mRNA transcription. Data normalization is an indispensable process for RT-qPCR and reference genes are most commonly used to normalize RT-qPCR and to reduce possible errors generated in the quantification of genes among several proposed methods. To date, RT-qPCR has been used in terms of gene expression studies in black rockfish (Sebastes schlegeli) but the majority of published RT-qPCR studies still lack proper validation of the reference genes. In the present study, mRNA transcription profiles of eight putative reference genes (18S rRNA, ACTB, GAPDH, TUBA, RPL17, EF1A, HPRT, and B2M) were examined using RT-qPCR in different tissues and larvae developmental stages of black rockfish. Three common statistical algorithms (geNorm, NormFinder, and BestKeeper) were used to assess expression stability and select the most stable genes for gene normalization. Two reference genes, RPL17 and EF1A showed high stability in black rockfish tissue analysis, while GAPDH was the least stable gene. During larvae developmental stages, EF1A, RPL17 and ACTB were identified as the optimal reference genes for data normalization, whereas B2M appeared unsuitable as the reference gene. In summary, our results could provide a useful guideline for reference gene selection and enable more accurate normalization of gene expression data in gene expression studies of black rockfish. [Copyright &y& Elsevier]

This study develops an expected utility model to examine Chinese fruit farmers' adoption of a newly introduced production technology, the artisan fruit production technique. We analyzed a three-stage adoption process and examined factors influencing farmers' adoption decision in each stage. Survey data collected from 398 fruit farmers were used to quantify farmers' probability to understand, actually adopt, and determine the magnitude of adoption. We found that farmers' adoption varies with their education, plans to expand, and their risk concerns regarding the new technology. We also detected that adoption changes with farm accessibility to government supported agricultural assistances and the availability of privately funded fruit cooperatives. Overall the three-stage adoption framework performs well in adjusting potential sample selection bias problems. [ABSTRACT FROM AUTHOR]

Abstract: A traditional assumption underlying most data converters is that the signal should be sampled at a rate exceeding twice the highest frequency. In this paper, we employ a method for low-rate sampling of multi- band signals via applying periodic nonuniform sampling in shift-invariant spaces generated by m kernels with period T. To avoid the non-ideal filter in traditional method, we use reconstruction functions to recovery the sampled signal completely. Finally, we validate the method in MATLAB; the conclusion of simulation shows the frame-work presented here is feasible. [Copyright &y& Elsevier]