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Bismuth-based compounds have been regarded as a kind of promising material due to their narrow bandgap, high carrier mobility, low toxicity, and strong oxidation ability, showing potential applications in the field of photoelectrochemical (PEC) activities. They can be applied in sustainable energy production, seawater desalination and treatment, optical detection and communication, and other fields. As a member of the broader family of bismuth-based materials, ß-Bi2O3 exhibits significant advantages for applications in engineering, including high photoelectric response, stability in harsh environments, and excellent corrosion resistance. This paper presents the synthesis of ß-Bi2O3 thin films utilizing the mist chemical vapor deposition (CVD) method at the optimal temperature of 400 °C. Based on the ß-Bi2O3 thin film synthesized at optimal temperature, a PEC-type photodetector was constructed with the highest responsivity R of 2.84 mA/W and detectivity D of 6.01 × 1010 Jones, respectively. The photodetection performance was investigated from various points like illumination light wavelength, power density, and long-term stability. This study would broaden the horizontal and practical applications of ß-Bi2O3.
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Myocardial ischemia-reperfusion injury (MIRI) frequently complicates postoperative cardiovascular disease treatment. Necroptosis, a cell death mechanism similar to apoptosis, is regulated by specific signaling pathways and plays an important role in MIRI. Receptor-interacting protein 3 (RIP3), a key protein regulating necroptosis during MIRI, directly phosphorylates calmodulin-dependent protein kinase II (CaMKII). Leading to mitochondrial permeablity transition pore (mPTP) opening and inducing necroptosis. Transient receptor potential canonical channel 6 (TRPC6) regulats Ca2+ entry, is linked to CaMKII as an important upstream effector. However, the connection between TRPC6 and MIRI necroptosis remains unclear. The study aimed to investigate the relationship between TRPC6 and MIRI necroptosis, with a specific focus on elucidating the role of TRPC6 in regulating CaMKII phosphorylation during cardiac necroptosis via Ca2+ modulation. METHODS AND RESULTS: The experiment used wild-type (WT) and TRPC6 knockout (TRPC6-/-) mice for I/R model construction, and H9c2 myocardial cell line for H/R model. After ischemia-reperfusion (I/R), TRPC6 protein levels in mice significantly increased, exacerbating myocardial injury, infarct size (IS), and cardiac function in WT mice. In contrast, TRPC6 knockout attenuated myocardial injury, IS, and improved cardiac function. The results showed a significant correlation between changes in CaMKII and TRPC6. TRPC6 knockout led to decreased intracellular calcium levels, CaMKII phosphorylation, reactive oxygen species levels, mPTP opening, and improve mitochondrial structure. CONCLUSION: I/R upregulates TRPC6, which mediates Ca2+ entry and CaMKII phosphorylation, exacerbates oxidative stress, and induces necroptosis. These findings suggest a potential therapeutic avenue for mitigating MIRI by targeting TRPC6.
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BACKGROUND: Skeletal muscle ischaemia-reperfusion injury (IRI) is a prevalent condition encountered in clinical practice, characterised by muscular dystrophy. Owing to limited treatment options and poor prognosis, it can lead to movement impairments, tissue damage, and disability. This study aimed to determine and verify the influence of transient receptor potential canonical 6 (TRPC6) on skeletal muscle IRI, and to explore the role of TRPC6 in the occurrence of skeletal muscle IRI and the signal transduction pathways activated by TRPC6 to provide novel insights for the treatment and intervention of skeletal muscle IRI. METHODS: In vivo ischaemia/reperfusion (I/R) and in vitro hypoxia/reoxygenation (H/R) models were established, and data were comprehensively analysed at histopathological, cellular, and molecular levels, along with the evaluation of the exercise capacity in mice. RESULTS: By comparing TRPC6 knockout mice with wild-type mice, we found that TRPC6 knockout of TRPC6 could reduced skeletal muscle injury after I/R or H/R, of skeletal muscle, so as therebyto restoringe some exercise capacity inof mice. TRPC6 knockdown can reduced Ca2+ overload in cells, therebyo reducinge apoptosis. In additionAdditionally, we also found that TRPC6 functionsis not only a key ion channel involved in skeletal muscle I/R injury, but also can affects Ca2+ levels and then phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/Akt/mTOR) signalling pathway. by knocking downTherefore, knockdown of TRPC6, so as to alleviated the injury inducedcaused by skeletal muscle I/R or and H/R. CONCLUSIONS: These findingsdata indicate that the presence of TRPC6 exacerbatescan aggravate the injury of skeletal muscle injury after I/Rischemia/reperfusion, leading towhich not only causes Ca2+ overload and apoptosis., Additionally, it impairsbut also reduces the self- repair ability of cells by inhibiting the expression of the PI3K/Akt/mTOR signalling pathway. ETo exploringe the function and role of TRPC6 in skeletal muscle maycan presentprovide a novelew approachidea for the treatment of skeletal muscle ischemia/reperfusion injury.
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Apoptosis , Ratones Noqueados , Músculo Esquelético , Daño por Reperfusión , Transducción de Señal , Canal Catiónico TRPC6 , Animales , Daño por Reperfusión/metabolismo , Daño por Reperfusión/patología , Canal Catiónico TRPC6/metabolismo , Canal Catiónico TRPC6/genética , Músculo Esquelético/metabolismo , Músculo Esquelético/patología , Ratones , Ratones Endogámicos C57BL , Proteínas Proto-Oncogénicas c-akt/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Masculino , Fosfatidilinositol 3-Quinasas/metabolismo , Calcio/metabolismoRESUMEN
Photoelectrochemical (PEC) technology in marine engineering holds significant importance due to its potential to address various challenges in the marine environment. Currently, PEC-type applications in marine engineering offer numerous benefits, including sustainable energy generation, water desalination and treatment, photodetection, and communication. Finding novel efficient photoresponse semiconductors is of great significance for the development of PEC-type techniques in the marine space. Bismuth-based semiconductor materials possess suitable and tunable bandgap structures, high carrier mobility, low toxicity, and strong oxidation capacity, which gives them great potential for PEC-type applications in marine engineering. In this paper, the structure and properties of bismuth binary and mixed-anion semiconductors have been reviewed. Meanwhile, the recent progress and synthetic approaches were discussed from the point of view of the application prospects. Finally, the issues and challenges of bismuth binary and mixed-anion semiconductors in PEC-type photodetection and hydrogen generation are analyzed. Thus, this perspective will not only stimulate the further investigation and application of bismuth binary and mixed-anion semiconductors in marine engineering but also help related practitioners understand the recent progress and potential applications of bismuth binary and mixed-anion compounds.
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The accurate (or even approximate) solution of the equations that govern the dynamics of dissipative quantum systems remains a challenging task in quantum science. While several algorithms have been designed to solve those equations with different degrees of flexibility, they rely mainly on highly expensive iterative schemes. Most recently, deep neural networks have been used for quantum dynamics, but current architectures are highly dependent on the physics of the particular system and usually limited to population dynamics. Here we introduce an artificial-intelligence-based surrogate model that solves dissipative quantum dynamics by parametrizing quantum propagators as Fourier neural operators, which we train using both data set and physics-informed loss functions. Compared with conventional algorithms, our quantum neural propagator avoids time-consuming iterations and provides a universal superoperator that can be used to evolve any initial quantum state for arbitrarily long times. To illustrate the wide applicability of the approach, we employ our quantum neural propagator to compute the population dynamics and time-correlation functions of the Fenna-Matthews-Olson complex.
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In the process of robot-assisted training for upper limb rehabilitation, a passive training strategy is usually used for stroke patients with flaccid paralysis. In order to stimulate the patient's active rehabilitation willingness, the rehabilitation therapist will use the robot-assisted training strategy for patients who gradually have the ability to generate active force. This study proposed a motor function assessment technology for human upper-limb based on fuzzy recognition on interaction force and human-robot interaction control strategy based on assistance-as-needed. A passive training mode based on the calculated torque controller and an assisted training mode combined with the potential energy field were designed, and then the interactive force information collected by the three-dimensional force sensor during the training process was imported into the fuzzy inference system, the degree of active participation σ was proposed, and the corresponding assisted strategy algorithms were designed to realize the adaptive adjustment of the two modes. The significant correlation between the degree of active participation σ and the surface electromyography signals (sEMG) was found through the experiments, and the method had a shorter response time compared to a control strategy that only adjusted the mode through the magnitude of interaction force, making the robot safer during the training process.
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Robótica , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Humanos , Robótica/métodos , Extremidad Superior , Algoritmos , Electromiografía/métodosRESUMEN
BACKGROUND: Auxin response factors (ARFs) are critical transcription factors that mediate the auxin signaling pathway and are essential for regulating plant growth. However, there is a lack of understanding regarding the ARF gene family in Liriodendron chinense, a vital species in landscaping and economics. Thus, further research is needed to explore the roles of ARFs in L. chinense and their potential applications in plant development. RESULT: In this study, we have identified 20 LcARF genes that belong to three subfamilies in the genome of L. chinense. The analysis of their conserved domains, gene structure, and phylogeny suggests that LcARFs may be evolutionarily conserved and functionally similar to other plant ARFs. The expression of LcARFs varies in different tissues. Additionally, they are also involved in different developmental stages of somatic embryogenesis. Overexpression of LcARF1, LcARF2a, and LcARF5 led to increased activity within callus. Additionally, our promoter-GFP fusion study indicated that LcARF1 may play a role in embryogenesis. Overall, this study provides insights into the functions of LcARFs in plant development and embryogenesis, which could facilitate the improvement of somatic embryogenesis in L. chinense. CONCLUSION: The research findings presented in this study shed light on the regulatory roles of LcARFs in somatic embryogenesis in L. chinense and may aid in accelerating the breeding process of this tree species. By identifying the specific LcARFs involved in different stages of somatic embryogenesis, this study provides a basis for developing targeted breeding strategies aimed at optimizing somatic embryogenesis in L. chinense, which holds great potential for improving the growth and productivity of this economically important species.
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Liriodendron , Liriodendron/genética , Fitomejoramiento , Factores de Transcripción/genética , Ácidos Indolacéticos/metabolismo , Genómica , Regulación de la Expresión Génica de las Plantas , Técnicas de Embriogénesis Somática de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMEN
The F-box gene family is one of the largest gene families in plants, and it plays a crucial role in regulating plant development, reproduction, cellular protein degradation, and response to biotic and abiotic stresses. Despite their significance, a comprehensive analysis of the F-box gene family in Liriodendron chinense and other magnoliaceae species has not been reported. In this study, we report for the first time the identification of 144 full-length F-box genes in L. chinense. Based on specific domains and phylogenetic analyses, these genes were divided into 10 distinct subfamilies. We further analyzed their gene structure, conserved domain and chromosome distribution, genome-wide replication events, and collinearity. Additionally, based on GO analysis, we found that F-box genes exhibit functional specificity, with a significant proportion of them being involved in protein binding (GO:0005515), suggesting that F-box genes may play an important role in gene regulation in L. chinense. Transcriptome data and q-PCR results also showed that F-box genes are involved in the development of multiple tissues in L. chinense, regulate the somatic embryogenesis of Liriodendron hybrids, and play a pivotal role in abiotic stress. Altogether, these findings provide a foundation for understanding the biological function of F-box genes in L. chinense and other plant species.
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Introduction: GRAS genes encode plant-specific transcription factors that play essential roles in plant growth and development. However, the members and the function of the GRAS gene family have not been reported in Liriodendron chinense. L. chinense, a tree species in the Magnolia family that produces excellent timber for daily life and industry. In addition, it is a good relict species for plant evolution research. Methods: Therefore, we conducted a genome-wide study of the LcGRAS gene family and identified 49 LcGRAS genes in L. chinense. Results: We found that LcGRAS could be divided into 13 sub-groups, among which there is a unique branch named HAM-t. We carried out RNA sequencing analysis of the somatic embryos from L. chinense and found that LcGRAS genes are mainly expressed after heart-stage embryo development, suggesting that LcGRAS may have a function during somatic embryogenesis. We also investigated whether GRAS genes are responsive to stress by carrying out RNA sequencing (RNA-seq) analysis, and we found that the genes in the PAT subfamily were activated upon stress treatment, suggesting that these genes may help plants survive stressful environments. We found that PIF was downregulated and COR was upregulated after the transient overexpression of PATs, suggesting that PAT may be upstream regulators of cold stress. Discussion: Collectively, LcGRAS genes are conserved and play essential roles in plant development and adaptation to abiotic stress.
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Electro-chemically reducing CO2 in a highly acidic medium is promising for addressing the issue of carbonate accumulation. However, the hydrogen evolution reaction (HER) typically dominates the acidic CO2 reduction. Herein, we construct an efficient electro-catalyst for CO formation based on a core-shell structure, where nitrogen-doped Ni nanoparticles coexist with nitrogen-coordinated Ni single atoms. The optimal catalyst demonstrates a significantly improved CO faradaic efficiency (FE) of 96.7 % in the acidic electrolyte (pH=1) at an industrial-scale current density of 500â mA cm-2 . Notably, the optimal catalyst maintains a high FE of CO exceeding 90 % (current density=500â mA cm-2 ) in the electrolyte with a wide pH range from 0.67 to 14. In-situ spectroscopic characterization and density functional theory calculations show that the local electron density of Ni-N-C sites is enhanced by N-doped Ni particles, which facilitates the formation of *COOH intermediate and the adsorption of *CO. This study demonstrates the potential of a hybrid metal/Ni-N-C interface in boosting acidic CO2 electro-reduction.
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The phytohormone abscisic acid (ABA) plays important roles in response to abiotic and biotic stresses in plants. Pyrabactin resistance 1-like (PYR/PYL) proteins are well-known as ABA receptors, which are responsible for ABA signal transduction. Nevertheless, the characteristics of PYL genes from Liriodendron chinense, an endangered timber tree, remain unclear in coping with various stresses. In this study, five PYLs were identified from the genome of Liriodendron chinense by sequence alignment and conserved motif analysis, which revealed that these LcPYLs contain a conserved gate and latch motif for ABA binding. The LcPYL promoters possess a series of cis-acting elements involved in response to various hormone and abiotic stresses. Moreover, the transcriptome data of Liriodendron hybrid leaves reveal that LcPYL genes specifically transcript under different abiotic stresses; Lchi11622 transcription was induced by drought and cold treatment, and Lchi01385 and Lchi16997 transcription was upregulated under cold and hot stress, respectively. Meanwhile, the LcPYLs with high expression levels shown in the transcriptomes were also found to be upregulated in whole plants treated with the same stresses tested by qPCR. Moreover, under biotic stress caused by scale insect and whitefly, Liriodendron hybrid leaves exhibited a distinct phenotype including disease spots that are dark green in the middle and yellow on the margin; the qPCR results showed that the relative expression levels of Lchi13641 and Lchi11622 in infected leaves were upregulated by 1.76 and 3.75 folds relative to normal leaves, respectively. The subcellular localizations of these stress-responsive LcPYLs were also identified in protoplasts of Liriodendron hybrid. These results provide a foundation to elucidate the function of PYLs from this elite tree species and assist in understanding the molecular mechanism of Liriodendron hybrid in dealing with abiotic and biotic stresses. In future research, the detailed biological function of LcPYLs and the genetic redundancy between LcPYLs can be explored by gene overexpression and knockout based on this study.
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To investigate the novel quantum dynamic behaviors of magnetic materials that arise from complex spin-spin interactions, it is necessary to probe the magnetic response at a speed greater than the spin-relaxation and dephasing processes. Recently developed two-dimensional (2D) terahertz magnetic resonance (THz-MR) spectroscopy techniques use the magnetic components of laser pulses, and this allows investigation of the details of the ultrafast dynamics of spin systems. For such investigations, quantum treatment-not only of the spin system itself but also of the environment surrounding the spin system-is important. In our method, based on the theory of multidimensional optical spectroscopy, we formulate nonlinear THz-MR spectra using an approach based on the numerically rigorous hierarchical equations of motion. We conduct numerical calculations of both linear (1D) and 2D THz-MR spectra for a linear chiral spin chain. The pitch and direction of chirality (clockwise or anticlockwise) are determined by the strength and sign of the Dzyaloshinskii-Moriya interaction (DMI). We show that not only the strength but also the sign of the DMI can be evaluated through the use of 2D THz-MR spectroscopic measurements, while 1D measurements allow us to determine only the strength.
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Introduction: The time-varying and individual variability of surface electromyographic signals (sEMG) can lead to poorer motor intention detection results from different subjects and longer temporal intervals between training and testing datasets. The consistency of using muscle synergy between the same tasks may be beneficial to improve the detection accuracy over long time ranges. However, the conventional muscle synergy extraction methods, such as non-negative matrix factorization (NMF) and principal component analysis (PCA) have some limitations in the field of motor intention detection, especially in the continuous estimation of upper limb joint angles. Methods: In this study, we proposed a reliable multivariate curve-resolved-alternating least squares (MCR-ALS) muscle synergy extraction method combined with long-short term memory neural network (LSTM) to estimate continuous elbow joint motion by using the sEMG datasets from different subjects and different days. The pre-processed sEMG signals were then decomposed into muscle synergies by MCR-ALS, NMF and PCA methods, and the decomposed muscle activation matrices were used as sEMG features. The sEMG features and elbow joint angular signals were input to LSTM to establish a neural network model. Finally, the established neural network models were tested by using sEMG dataset from different subjects and different days, and the detection accuracy was measured by correlation coefficient. Results: The detection accuracy of elbow joint angle was more than 85% by using the proposed method. This result was significantly higher than the detection accuracies obtained by using NMF and PCA methods. The results showed that the proposed method can improve the accuracy of motor intention detection results from different subjects and different acquisition timepoints. Discussion: This study successfully improves the robustness of sEMG signals in neural network applications using an innovative muscle synergy extraction method. It contributes to the application of human physiological signals in human-machine interaction.
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Liriodendron chinense is a tree species of the Magnoliaceae family, an ancient relict plant mainly used for landscaping and timber production due to its excellent material properties and ornamental value. The cytokinin oxidase/dehydrogenase (CKX) enzyme regulates cytokinin levels and plays an important role in plant growth, development, and resistance. However, too-high or too-low temperatures or soil drought can limit the growth of L. chinense, representing a key issue for research. Here, we identified the CKX gene family in the L. chinense genome and examined its transcriptional responses to cold, drought, and heat stresses. A total of five LcCKX genes, distributed on four chromosomes and divided into three phylogenetic groups, were identified across the whole L. chinense genome. Further analysis showed that multiple hormone- and stress-responsive cis-acting elements are located in the promoter regions of LcCKXs, indicating a potential role of these LcCKXs in plant growth, development, and response to environmental stresses. Based on existing transcriptome data, LcCKXs, especially LcCKX5, were found to transcriptionally respond to cold, heat, and drought stresses. Furthermore, quantitative reverse-transcription PCR (qRT-PCR) showed that LcCKX5 responds to drought stress in an ABA-dependent manner in stems and leaves and in an ABA-independent manner in roots. These results lay a foundation for functional research on LcCKX genes in the resistance breeding of the rare and endangered tree species of L. chinense.
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Robot-assisted rehabilitation therapy has been proven to effectively improve upper-limb motor function in stroke patients. However, most current rehabilitation robotic controllers will provide too much assistance force and focus only on the patient's position tracking performance while ignoring the patient's interactive force situation, resulting in the inability to accurately assess the patient's true motor intention and difficulty stimulating the patient's initiative, thus negatively affecting the patient's rehabilitation outcome. Therefore, this paper proposes a fuzzy adaptive passive (FAP) control strategy based on subjects' task performance and impulse. To ensure the safety of subjects, a passive controller based on the potential field is designed to guide and assist patients in their movements, and the stability of the controller is demonstrated in a passive formalism. Then, using the subject's task performance and impulse as evaluation indicators, fuzzy logic rules were designed and used as an evaluation algorithm to quantitively assess the subject's motor ability and to adaptively modify the stiffness coefficient of the potential field and thus change the magnitude of the assistance force to stimulate the subject's initiative. Through experiments, this control strategy has been shown to not only improve the subject's initiative during the training process and ensure their safety during training but also enhance the subject's motor learning ability.
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Robótica , Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Humanos , Robótica/métodos , Extremidad Superior , Resultado del TratamientoRESUMEN
Recent years have witnessed important developments in the emerging field of magneto-mechanical therapies. While such approaches have been demonstrated as a highly efficient route to augment, complement, or entirely replace other therapeutic strategies, important aspects are still poorly understood. Among these, the dependence between the cell death pathway and the geometry of magnetic nanocomposites enabling magneto-mechanical therapies under a low-frequency rotating magnetic field (RMF) is yet to be deciphered. To provide insights into this important problem, we evaluate the cell death pathway for two magnetic nanocomposites with highly distinct geometries: Zn0.2Fe2.8O4-PLGA magnetic nanospheres (MNSs) and Zn0.2Fe2.8O4-PLGA magnetic nanochains (MNCs). We show that under exposure to an RMF, the MNSs and the MNCs exhibit a corkscrewed circular propulsion mode and a steering propulsion mode, respectively. This distinct behavior, with important implications for the associated magneto-mechanical forces exerted by these nanomaterials on surrounding structures (e.g., the cellular membrane), depends on their specific geometries. Next, using numerical simulations and cell viability experiments, we demonstrate that the field strength of the RMF and the rotating speed of the MNSs or MNCs have strong implications for their magneto-mechanical therapeutic performance. Last, we reveal that the magneto-mechanical effects of MNSs are more prone to induce cell apoptosis, whereas those of the MNCs favor instead cell necrosis. Overall, this work enhances the current understanding of the dependences existing between the magneto-mechanical therapeutic effects of magnetic nanocomposites with different geometries and associated cell death pathways, paving the way for novel functionalization routes which could enable significantly enhanced cures and biomedical tools. STATEMENT OF SIGNIFICANCE.
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Magnetismo , Nanocompuestos , Muerte Celular , Apoptosis , Campos Magnéticos , Nanocompuestos/químicaRESUMEN
In order to achieve a comprehensive evaluation of the environmental impact of ecological restoration projects (ERP) under the current destruction and restoration of coastal ecological areas, this paper takes into account the impact of positive and negative indicators on the environment; analyzes the positive and negative benefits of ERP; and establishes a comprehensive environmental impact index system for marine ERP from ecological, economic, and social perspectives through the DPSIR model. On this basis, the cloud model and Monte Carlo simulation are used to obtain the comprehensive assessment grade of the construction period, short-term operation, and long-term operation in the project life cycle. The results show that the benefits of ERP, considering the impact of negative factors, are significantly reduced, and the benefits of ERP will increase remarkably in the long-term operation period. In engineering practice, the environmental pressure factor caused by excessive human activities during construction and operation periods is a key negative factor affecting the overall benefits of ERP. For project decision makers and other stakeholders, the comprehensive assessment grade considering negative impacts is more practical. At the same time, decision makers should take active response measures in the framework of long-term sustainable development, set a tolerance threshold for negative pressure indicators, and strengthen the management of ERP.
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Ambiente , Actividades Humanas , Humanos , Biología Marina , Ecosistema , Conservación de los Recursos Naturales/métodosRESUMEN
The partition function (PF) plays a key role in the calculation of quantum thermodynamic properties of a system that interacts with a heat bath. The imaginary-time hierarchical equations of motion (imHEOM) approach was developed to evaluate in a rigorous manner the PF of a system strongly coupled to a non-Markovian bath. In this paper, we present a numerically efficient scheme to evaluate the imHEOM utilizing the ß-differentiated imHEOM (BD-imHEOM) that are obtained by differentiating the elements of the imHEOM with respect to the inverse temperature. This approach allows us to evaluate the system, system-bath interaction, and heat-bath parts of the PF efficiently. Moreover, we employ a polyharmonic decomposition method to construct a concise hierarchical structure with better convergence, thus reducing the cost of numerical integrations. We demonstrate the proposed approach by compute thermodynamic quantities of a spin-boson system and a 2 × 2 antiferromagnetic triangular spin lattice system with an Ohmic spectral distribution.
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Casuarina equisetifolia, as windbreaks, soil erosion, and sand dune stabilization with high resistant to typhoon force winds, drought and salinization, belongs to the Casuarinaceae family. In this study, the complete chloroplast genome of C. equisetifolia was sequenced by Illumina sequencing platform and annotated by Geneious Prime. The complete chloroplast genome size is 156,128 bp in length, with a large single copy region (LSC: 86,192 bp) and a small single-copy region (SSC: 18,462 bp), which was separated by a pair of 25,737 bp inverted repeated regions (IRs). The chloroplast genome of C. equisetifolia encodes total 127 genes, including 82 protein-coding genes, 37 tRNA genes, and eight rRNA genes. The phylogenomic relationship analysis suggested that the Casuarinaceae family, which includes C. equisetifolia, was more closely related to the family of Betulaceae.
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Liriodendron chinense (Lchi) is a Magnoliaceae plant, which is a basic angiosperm left behind by the Pleistocene and mainly distributed in the south of the Yangtze River. Liriodendron hybrids has good wood properties and is widely used in furniture and in other fields. It is not clear if they can adapt to different environmental conditions, such as drought and high and low temperatures, and the molecular mechanisms for this adaptation are unknown. Among plant transcription factors (TFs), the MYB gene family is one of the largest and is often involved in stress or adversity response signaling, growth, and development. Therefore, studying the role of MYBTFs in regulating abiotic stress signaling, growth, and development in Lchi is helpful to promote afforestation in different environments. In our research, a genome-wide analysis of the LchiMYB gene family was performed, including the phylogenetic relationship tree, gene exon-intron structure, collinearity, and chromosomal position. According to the evolutionary tree, 190 LchiMYBs were divided into three main branches. LchiMYBs were evenly distributed across 19 chromosomes, with their collinearity, suggesting that segment duplication events may have contributed to LchiMYB gene expansion. Transcriptomes from eight tissues, 11 stages of somatic embryogenesis, and leaves after cold, heat, and drought stress were used to analyze the function of the MYB gene family. The results of tissue expression analysis showed that most LchiMYB genes regulated bark, leaf, bud, sepal, stigma, and stamen development, as well as the four important stages (ES3, ES4, ES9, and PL) of somatic embryogenesis. More than 60 LchiMYBs responded to heat, cold, and drought stress; some of which underwent gene duplication during evolution. LchiMYB3 was highly expressed under all three forms of stress, while LchiMYB121 was strongly induced by both cold and heat stress. Eight genes with different expression patterns were selected and verified by quantitative real-time PCR (qRT-PCR) experiments. The results suggested that these LchiMYBs may regulate Lchi growth development and resistance to abiotic stress. This study shows the cross-regulatory function of LchiMYBs in the growth and development, asexual reproduction, and abiotic resistance of Lchi. This information will prove pivotal to directing further studies on the biological function of Lchi MYBTFs in genetic improvement and abiotic stress response.