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Solid–liquid phase equilibria of the quaternary system (Li+,K+// , –H2O) and its subsystem are very important for the separation of lithium and potassium salts from the salt lake brines. In this paper, the solubilities, densities, refractive indices and pH values of the reciprocal quaternary system (Li+,K+// , –H2O) at 308.15 K were determined experimentally using the isothermal dissolution method. The dry-salt diagram and water-phase diagram were plotted based on the experimental data. The stable phase diagram contains four invariant points, nine univariant curves and six crystallization regions corresponding to Li2CO3, Li2CO3⋅K2CO3, K2CO3⋅1.5H2O, Li2SO4⋅H2O, K2SO4, and Li2SO4⋅K2SO4. Li2CO3 has the largest crystallization field, whereas the Li2CO3⋅K2CO3 crystallization field is the smallest one. [ABSTRACT FROM AUTHOR]

Mitochondrial protein sequence similarity 3 gene family member A (FAM3A) plays important roles in the electron transfer chain, while its functions in the heart are still unknown. This study aims to explore the roles and mechanisms of FAM3A after myocardial infarction (MI). FAM3A-deficient (Fam3a−/−) mice were implemented with MI injury and showed lower survival rates at 4 weeks as well as decreased cardiac systolic function. Isolated cardiomyocytes of Fam3a−/− mice showed reduced basal, ATP-linked respiration and respiratory reserve compared to that of wild-type mice. Transmission electron microscopy studies showed Fam3a−/− mice had a larger size and elevated density of mitochondria. FAM3A deficiency also induced elevated mitochondrial Ca2+, higher opening level of mPTP, lower mitochondrial membrane potential and elevated apoptotic rates. Further analyses demonstrated that mitochondrial dynamics protein Opa1 contributed to the effects of FAM3A in cardiomyocytes. Our study discloses the important roles of mitochondrial protein FAM3A in the heart. [ABSTRACT FROM AUTHOR]

The Chinese government aims at reducing nutrients losses from agriculture through incentivising the substitution of synthetic fertilizer by animal manure applications. This paper addresses the question how different substitution ratios affect crop yield, nitrogen (N) utilization efficiency (NUE), ammonia (NH3) volatilization and the N balance of a typical winter wheat–summer maize double cropping system. A field experiment was conducted with six treatments, including a no N treatment and five N substitution ratios (100%, 75%, 50%, 25% and 0%), between October 2016 and September 2018. The yield and NUE were highest with a partial N substitution (75% inorganic N fertilizer + 25 manure N). Mean yields were 8553 kg ha−1 for wheat and 10,620 kg ha−1 for maize in the treatment with 75% inorganic N + 25% manure N. Mean NUE was 55% for wheat and 45% for maize in this treatment. The mean N balance, N uptake, and soil residual Nmin increased, while NH3 emissions and N surpluses decreased with an increasing substitution of synthetic N fertilizer by manure N. A substitution of 25% of the inorganic N fertilizer by manure N showed the best performance. Selecting the appropriate ratio of synthetic N fertilizer to manure is an effective pathway for green agricultural development, as it ensures a high crop yield and N utilization, and reduces the environmental cost of food production. [ABSTRACT FROM AUTHOR]

Polygonatum sibiricum is a perennial herb belonging to the Asparagaceae family with numerous medical and nutritional uses. In this study, we used the MaxEnt to predict the suitable habitat of P. sibiricum and analyzed the phenotypes of P. sibiricum in 22 regions by combining the collection and survey of wild resources. The results showed that with the changes of time and climate, the suitable areas of P. sibiricum all decreased to different degrees in the future period and gradually tended to shift to the northwest. In addition, climatic factors such as annual relative humidity, rainfall, and average air temperature had significant impact on the quality of P. sibiricum, and leaf width, number of leaf whorls, pedicel length and total number of flowers were significantly correlated with other traits. In this study, the comprehensive analysis of the germplasm resources and the prediction of P. sibiricum distribution provided useful information for the conservation, exploitation, and utilization of P. sibiricum resources. [ABSTRACT FROM AUTHOR]

With traditional Chinese medicine playing an increasingly important role in human society, the scarcity of wild resources has become a key constraint to the development of the industry. For this study, optimized maximum entropy models were employed to predict the patterns and changes in potentially suitable distribution areas for Thesium chinense Turcz. in China, in the present (1970–2000) and future (2050s, 2070s, and 2090s) under multiple climate scenarios (SSP1-2.6, SSP2-4.5, SSP3-7.0, and SSP5-8.5). The results showed that the predicted regions of high, medium, and low potential fitness zones were 6.19 × 104, 150.99 × 104, and 155.61 × 104 km2. The highly suitable areas were primarily found in Shandong and Shanxi Provinces. Furthermore, we found its relatively stable habitat was mainly distributed across South Central Shanxi, Eastern Gansu, and Midwest Guizhou. An analysis of the transfer of masses revealed that the potential habitat of the plant migrated in a northwesterly direction under various climatic conditions. [ABSTRACT FROM AUTHOR]

A general and adaptable method is proposed to reliably extract quantitative information from smartphone images of microfluidic sensors. By analyzing and processing the color information of selected standard substances, the influence of light conditions, device differences, and human factors could be significantly reduced. Machine learning and multivariate fitting methods were proved to be effective for chroma correction, and a key element was the training of sample size and the fitting form, respectively. A custom APP was developed and validated using a high-sensitivity chromium ion quantification paper chip. The average chroma deviations under different conditions were reduced by more than 75% in RGB color space, and the concentration test error was reduced by more than half compared with the commonly used method. The proposed approach could be a beneficial supplement to existing and potential colorimetry-based detection methods. [ABSTRACT FROM AUTHOR]

Even though the perovskite solar cell has been so popular for its skyrocketing power conversion efficiency, its further development is still roadblocked by its overall performance, in particular long-term stability, large-area fabrication and stable module efficiency. In essence, the soft component and ionic–electronic nature of metal halide perovskites usually chaperonage large number of anion vacancy defects that act as recombination centers to decrease both the photovoltaic efficiency and operational stability. Herein, we report a one-stone-for-two-birds strategy in which both anion-fixation and associated undercoordinated-Pb passivation are in situ achieved during crystallization by using a single amidino-based ligand, namely 3-amidinopyridine, for metal-halide perovskite to overcome above challenges. The resultant devices attain a power conversion efficiency as high as 25.3% (certified at 24.8%) with substantially improved stability. Moreover, the device without encapsulation retained 92% of its initial efficiency after 5000 h exposure in ambient and the device with encapsulation retained 95% of its initial efficiency after >500 h working at the maximum power point under continuous light irradiation in ambient. It is expected this one-stone-for-two-birds strategy will benefit large-area fabrication that desires for simplicity. Long-term stability and stable efficiency are essential for large-area fabrication of perovskite solar cells. Here, the authors achieve in situ anion-fixation and undercoordinated-Pb passivation using amidino-based ligand, realizing maximum power conversion efficiency of 25.3% with T95 over 500 h. [ABSTRACT FROM AUTHOR]

Due to the heterogeneity of program language and natural language query, it is difficult to identify the semantic relationship between them, which leads to the low efficiency of code recommendation. In order to solve the problems of the above code recommendation technology, a code recommendation method based on joint embedded attention network (JEAN) is proposed in this paper. The method uses GRU Network to embed code snippets and describe queries into vector representation, which solves the problem of heterogeneous code snippets and natural language queries. The Attention mechanism is then used to distribute totally different weights to different components of every mode of the code snippet. The reason for the Attention mechanism is that different components of every mode of the code snippet contribute differently to the semantic vector of the final code snippet, making it interpretable. Finally, two commonly used evaluation indexes of information retrieval, SuccessRate@k and MRR, are used for experimental comparison with other baseline models. The experimental results show that the code recommendation method based on joint embedded attention network proposed in this paper can effectively recommend appropriate code snippets according to the needs of developers, and its performance is better than other baseline methods. [ABSTRACT FROM AUTHOR]

The deep rocks generally present high strength, plasticity and abrasiveness, which greatly limit the efficient drilling of the bit. Particle impact drilling (PID) technology is a new and efficient drilling method, but its rock-breaking mechanism is still unclear. In present study, a numerical model which truly reflects the mineral composition and granule diameter distribution of granite is established based on the particle flow code (PFC) to optimize the particle impact parameters. The law and mechanism of rock breaking by single particle impact, multi-particle impact and auxiliary cutting with different particle diameter, incident angle and incident velocity are studied. The results showed that the crack number and broken volume fluctuate with the change of incident parameters. Microcracks mostly occur in the longitudinal direction of rock. During particle impact, the formation, expansion and coalescence of microcracks are all along the mineral crystal, while the situation is just the opposite in cutting. With particle impact assisted, the cutter can easily penetrate into the rock and the rock presents brittle failure. This research also includes experiments to examine the generation of cracks and chips. To improve the efficiency of auxiliary rock breaking, it is recommended to use particles with a diameter of 3.0 mm and an incident angle of 0°–30°, while increasing the impact velocity. This study deepens the understanding of the mechanism of rock breaking assisted by particle impact, and provides the basis for designing drilling parameters using the PID technology. [ABSTRACT FROM AUTHOR]

Multi-oriented objects widely appear in scene texts and optical remote sensing images, and thus rotation detection has received considerable attention. However, we observe that few arbitrary-oriented ship detection methods for synthetic aperture radar (SAR) images have been proposed before. The main reasons are the essential difference between SAR images and optical remote sensing images and the lack of labeled data for training rotation detectors. In addition, there also exist these problems of arbitrary orientation, large aspect ratio, and dense arrangement in SAR ship detection task. To address these above issues, an arbitrary-oriented ship detection method named FSFADet based on feature separation and feature alignment is proposed. Considering the lack of labeled SAR images, we establish a new SAR ship rotation detection dataset named SSRDD dataset, which is an important task when using arbitrary-oriented ship detection approaches for SAR data. A feature separation module (FS-Module) is introduced to enhance the ship object feature and weaken the background noise. Meanwhile, a refined network (R-Network) and a feature alignment module (FA-Module) are introduced to boost the SAR ship detection performance. Finally, the IoU-smooth L1 loss is introduced to the loss function to address the boundary problem. The simulation experiments show that the proposed method is superior to other arbitrary-oriented object detection methods. [ABSTRACT FROM AUTHOR]

In this paper, bursting behaviors triggered by the pulse-shaped explosion (abbreviated as PSE) phenomenon and bifurcation structures are investigated in a parametrically and externally forced van der Pol–Mathieu system. The PSE, characterized by the pulse-shaped quantitative of the system solutions changing sharply at some values, is an innovative route to bursting oscillations reported recently. Three PSE-induced bursting types, namely intermittent "supHopf/supHopf-supHopf/supHopf" bursting via "PSE/PSE" hysteresis loop, "supHopf/supHopf" bursting via "PSE/PSE" hysteresis loop and "supHopf/supHopf" bursting via "supHopf/PSE" hysteresis loop, are investigated in detail by using the slow/fast analysis technology, time series analysis and phase diagram. We present a fact that the system parameters affect the positions of the PSE points, the types of the spiking states and the bursting forms. This paper adds the diversity of the bursting patterns triggered by the PSE and reveals some essential properties of bursting oscillations. In addition, the numerical simulations are used to test and verify the correctness of the theoretical analysis. [ABSTRACT FROM AUTHOR]

We consider a mixed duopoly selling to downstream retailers that are engaged in spatial price discrimination. We show that the optimal degree of privatization falls below—often far below—the level that is implied in the absence of the vertical chain. The size of this reduction in privatization reflects the extent to which increasing transport cost (differentiation) increases double marginalization in contested market regions—as opposed to simply reducing demand in uncontested market regions. Moreover, we show that despite higher costs of production, a fully public monopoly upstream can be welfare-superior to the optimal mixed duopoly. This would not be the case in the absence of downstream differentiation. [ABSTRACT FROM AUTHOR]

Aims: In the production of the natural medicinal plant American ginseng, replantation typically fails due to continuous cropping obstacles. However, the cause is still not clear and needs more research. Methods: Soil samples were collected from (a) maize fields where American ginseng had never been planted, (b) fields where American ginseng had just been harvested, and (c) fields where maize had been planted for 2, 4 and 6 years respectively after American ginseng. We investigated the physicochemical properties, the enzymatic activities, and the soil microbial community structure and composition of the samples. Results: We found that the content of soil salt, NH4+-N, and NO3−-N increased significantly in samples associated with the production of American ginseng, whereas the soil pH, carbon-to-nitrogen ratio, alkaline phosphatase, and cellulase activity all significantly decreased and gradually recovered to the pre-planting level. Moreover, the bacterial diversity decreased, while fungal diversity and richness increased; fungal richness continued to increase in farmlands replanted maize. The relative abundance of some microbial communities was changed significantly and was gradually restored with a longer time to replant maize. Pearson's correlation analysis shown that significantly changed microbial communities were significantly associated with changes in soil pH, soil salt and nitrogen content, alkaline phosphatase, and cellulase activity. Conclusions: Changes in soil pH, soil salt and nitrogen content caused changes in microbial community structure and composition, as well as cellulase and alkaline phosphatase activity. These changes may cause the continuous cropping obstacles of American ginseng and may be improved by planting maize. [ABSTRACT FROM AUTHOR]

The beating heart possesses the intrinsic ability to adapt cardiac output to changes in mechanical load. The century-old Frank–Starling law and Anrep effect have documented that stretching the heart during diastolic filling increases its contractile force. However, the molecular mechanotransduction mechanism and its impact on cardiac health and disease remain elusive. Here we show that the mechanically activated Piezo1 channel converts mechanical stretch of cardiomyocytes into Ca2+ and reactive oxygen species (ROS) signaling, which critically determines the mechanical activity of the heart. Either cardiac-specific knockout or overexpression of Piezo1 in mice results in defective Ca2+ and ROS signaling and the development of cardiomyopathy, demonstrating a homeostatic role of Piezo1. Piezo1 is pathologically upregulated in both mouse and human diseased hearts via an autonomic response of cardiomyocytes. Thus, Piezo1 serves as a key cardiac mechanotransducer for initiating mechano-chemo transduction and consequently maintaining normal heart function, and might represent a novel therapeutic target for treating human heart diseases. The beating heart adapts cardiac output to changes in mechanical load via incompletely understood mechanotransduction mechanisms. Here the authors show that the mechanosensitive Piezo1 channel serves as a mechanotransducer for directly converting mechanical stretch of cardiomyocytes into Ca2+ and ROS signaling and consequently maintaining normal heart function. [ABSTRACT FROM AUTHOR]

Solid–liquid phase equilibria for the two aqueous systems (LiBO2 + NaBO2 + H2O) and (LiBO2 + KBO2 + H2O) at T = 288.15 K and p = 0.1 MPa were determined using the isothermal dissolution equilibrium method. The experimental results show that the phase diagrams consist of one two-salt co-saturated invariant point, two univariant solubility isotherms, and three crystallization fields. The two systems belong to simple co-saturated type, and neither double salt nor solid solution were found. The densities change regularly as the sodium metaborate (potassium metaborate) concentration increases in solution, and reach their maximum values at the invariant point. Based on the Pitzer and its extended Harvie–Møller–Weare (HMW) model, the solubilities for the ternary systems at 288.15 K were represented, and the calculated results agree well with the experimental values. [ABSTRACT FROM AUTHOR]

An 87-year-old woman developed abdominal wall hematoma and upper gastrointestinal bleeding during treatment with cefoperazone/sulbactam for pneumonia. The woman received cefoperazone/sulbactam at 4.5 g twice daily for intravenous infusion. After 7 days, she developed sudden onset of left lower abdominal pain, associated with subcutaneous mass, and vomited a coffee-colored liquid. Investigations revealed a coagulation index abnormality and activated partial thromboplastin time and prothrombin time increased obviously. She was diagnosed with cefoperazone-induced hemorrhage. Cefoperazone/sulbactam was discontinued and the patient received vitamin K1. The blood coagulation function improved and hematoma disappeared after 3 days. A Naranjo assessment score of 6 was obtained, indicating a probable relationship between the patient's coagulation function disorder and her use of the suspect drug. [ABSTRACT FROM AUTHOR]

The solubilities and physicochemical properties, including density and pH, in the ternary system (LiBO + CaBO + HO) at (288.15 and 298.15) K were investigated using the isothermal dissolution equilibrium method. According to the experimental results of the ternary system at (288.15 and 298.15) K, the stable phase diagrams and the diagrams of physicochemical properties were plotted versus composition. In the phase diagrams of the ternary system at (288.15 and 298.15) K, there is one invariant point (LiBO·8HO + CaBO·6HO), two univariant isotherm dissolution curves, and two crystallization regions corresponding to lithium metaborate octahydrate (LiBO·8HO) and calcium metaborate hexahydrate (CaBO·6HO), respectively. This system at both temperatures belongs to hydrate type I classification and neither double salt nor solid solution were found. A comparison of the phase diagrams for the ternary system at (288.15 and 298.15) K shows that the numbers of solid phase and the minerals present are the same; the crystallized area of CaBO·6HO increased at the higher temperature, while that of LiBO·8HO decreased. The physicochemical properties (density and pH values) of the ternary system at the two temperatures change regularly with increasing lithium metaborate concentration. The calculated values of density using empirical equations of the ternary system are in good agreement with the experimental values. [ABSTRACT FROM AUTHOR]

The radar signal sorting method based on traditional support vector clustering (SVC) algorithm takes a high time complexity, and the traditional validity index cannot efficiently indicate the best sorting result. Aiming at solving the problem, we study a new sorting method based on cone cluster labeling (CCL) method. The CCL method relies on the theory of approximate coverings both in feature space and data space. Also a new cluster validity index, similitude entropy (SE), is proposed. It can be used to evaluate the compactness and separation of clusters with information entropy theory. Simulations including the performance comparison between the proposed method and the conventional methods are presented. Results show that while maintaining the sorting accuracy, the proposed method can reduce the computing complexity effectively in sorting the signals. [ABSTRACT FROM AUTHOR]

The T-tubule (TT) system forms the structural basis for excitation-contraction coupling in heart and muscle cells. The morphogenesis of the TT system is a key step in the maturation of heart cells because it does not exist in neonatal cardiomyocytes. In the present study, we quantified the morphological changes in TTs during heart cell maturation and investigated the role of junctophilin-2 (JP2), a protein known to anchor the sarcoplasmic reticulum (SR) to TT, in changes to TT morphological parameters. Analysis of confocal images showed that the transverse elements of TTs increased, while longitudinal elements decreased during the maturation of TTs. Fourier transform analysis showed that the power of ∼2 μm spatial components increased with cardiomyocytes maturation. These changes were preceded by increased expression of JP2, and were reversed by JP2 knockdown. These findings indicate that JP2 is required for the morphogenesis of TTs during heart development. [ABSTRACT FROM AUTHOR]

Reports on a dynamic model for non-Fickian diffusion of calcium spark in cardiac myocytes. Development of the model with time lags based on the microscale mass transport theory; Numerical simulation showing the size of the calcium spark was larger than the one produced by Fick diffusion; Suggestion the new model's simulation is closer to experimental results; Finding that the calcium spark time lags in cardiac myocytes were about 0.1-0.8 ms; Implication for understanding the mechanism of calcium spark diffusion.

With confocal microscopy, we recorded calcium transients and analyzed calcium removal rate at different temperatures in cardiac myocytes from the rat, a non-hibernator, and the ground squirrel, a hibernator. The results showed a remarkable increase of the diastolic level of calcium transients in the rat but no detectable change in the ground squirrel. Calcium transient of the ground squirrel, compared with that of the rat at the same temperature, had a shorter duration and showed a faster calcium removal. As indicated by the pharmacological effect of cyclopiazonic acid, calcium uptake by sarcoplasmic reticulum (SR) was the major mechanism of calcium removal, and was faster in the ground squirrel than in the rat. Our results confirmed the essential role of SR in hypothermia-tolerant adaptation, and negated the importance of Na-Ca exchange. We postulated the possibility to improve hypothermia-tolerance of the cardiac tissue of non-hibernating mammals. [ABSTRACT FROM AUTHOR]

The temperature-dependence of intracellular free calcium ([Ca2+]i) was investigated in indo-1 loaded ventricular myocytes from the rat, a non-hibernator, and from the ground squirrel, a hibernator. The dissociation constant of indo-1 at different temperatures was calibrated both at pH-stat and at α-stat, and the result demonstrated that the α-stat calibration should be preferred. Analysis of the fluorescent image showed a striking increase of [Ca2+]i as well as spontaneous calcium waves in rat cells, indicating an overloaded calcium. In contrast, cardiac myocytes of the ground squirrel were found to keep a constant [Ca2+]i without calcium overload regardless of temperature variation. It is believed that understanding of the mechanisms underlying the intercellular calcium homeostasis of hibemators may lead to solutions of some medical questions. [ABSTRACT FROM AUTHOR]

Tests Effinger and Hayes' theorem about the Goldbach 3-primes property for polynomial rings over certain infinite fields. Application of the model-theoretic method in the investigation; Existence of infinitely many fields that satisfy Goldbach 3-primes property.

A complete solution to the diagonalization problem (under equivalence) for row-column-finite infinite matrices over a general field is given [ABSTRACT FROM AUTHOR]