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Sunspots play a crucial role in both weather forecasting and the monitoring of solar storms. In this work, we propose a novel combined model for sunspot prediction using improved gated recurrent units (GRU) guided by pinball loss for probabilistic forecasts. Specifically, we optimize the GRU parameters using the slime mould algorithm and employ a seasonal-trend decomposition procedure based on loess to tackle challenges related to sequence prediction, such as self-correlations and non-stationarity. To address prediction uncertainty, we replace the traditional l 2 -norm loss with pinball loss. This modification extends the conventional GRU-based point forecasting to a probabilistic framework expressed as quantiles. We apply our proposed model to analyze a well-established historical sunspot dataset for both single- and multi-step ahead forecasting. The results demonstrate the effectiveness of our combined model in predicting sunspot values, surpassing the performance of other existing methods. [ABSTRACT FROM AUTHOR]

Karyotyping requires chromosome instances to be segmented and classified from the metaphase images. One of the difficulties in chromosome segmentation is that the chromosomes are randomly positioned in the image, and there is a great chance for chromosomes to be touched or overlap with others. It is always much easier for operators and automatic programs to tackle images without overlapping chromosomes than ones with largely overlapped chromosomes. In order to reduce the processing difficulty, adding a smart image selection procedure ahead of segmentation is practical and necessary. In this paper, we introduce the Smart Karyotyping Image Selection (SKIS) based on Commonsense Knowledge Reasoning. The initial experiment demonstrates that the proposed approach can select the expected images based on reasoning and benefit following karyotyping processes. [ABSTRACT FROM AUTHOR]

Crimean–Congo hemorrhagic fever (CCHF), caused by Crimean–Congo Hemorrhagic virus (CCHFV), is listed in the World Health Organization's list of priority diseases. The high fatality rate in humans, the widespread distribution of CCHFV, and the lack of approved specific vaccines are the primary concerns regarding this disease. We used microfluidic technology to optimize the mRNA vaccine delivery system and demonstrated that vaccination with nucleoside-modified CCHFV mRNA vaccines encoding GnNSmGc (vLMs), Gn (vLMn), or Gc (vLMc) induced different immune responses. We found that both T-cell and B-cell immune responses induced by vLMc were better than those induced by vLMn. Interestingly, immune responses were found to be lower for vLMs, which employed NSm to link Gn and Gc for non-fusion expression, compared to those for vLMc. In conclusion, our results indicated that NSm could be a factor that leads to decreased specific immune responses in the host and should be avoided in the development of CCHFV vaccine antigens. [ABSTRACT FROM AUTHOR]

Nitrogen-vacancy centers in diamond have been developed as a sensitive magnetic sensor and broadly applied on condensed matter physics. We present a design of a scanning probe microscope based on a nitrogen-vacancy center that can operate under various experimental conditions, including a broad temperature range (20–500 K) and a high-vacuum condition (1 × 10−7 mbar). The design of a compact and robust scanning head and vacuum chamber system is presented, which ensures system stability while enabling the convenience of equipment operations. By showcasing the temperature control performance and presenting confocal images of a single-layer graphene and a diamond probe, along with images of a ferromagnetic strip and an epitaxial BiFeO3 film on the SrTiO3 substrate, we demonstrate the reliability of the instrument. Our study proposes a method and a corresponding design for this microscope that extends its potential applications in nanomagnetism and spintronics. [ABSTRACT FROM AUTHOR]

Bismuth ferrite (BiFeO3) possesses a non‐collinear spin order while the ferroelectric order breaks space inversion symmetry. This allows efficient electric‐field control of magnetism and makes it a promising candidate for applications in low‐power spintronic devices. Epitaxial strain effects have been intensively studied and exhibit significant modulation of the magnetic order in bismuthBiFeO3, but tuning its spin structure with continuously varied uniaxial strain is still lacking at this moment. Herein, in situ uniaxial tensile strain is applied to a freestanding BiFeO3 film by mechanically stretching an organic substrate. A scanning nitrogen‐vacancy (NV) microscopy is applied to image the nanoscale magnetic order in real space. The strain is continuously increased from 0% to 1.5% and four images under different strains are acquired during this period. The images show that the spin cycloid tilts by ≈12.6° when strain approaches 1.5%. A first principle calculation is processed to show that the tilting is energetically favorable under such strain. The in situ strain applying method in combination with scanning NV microscope real‐space imaging ability paves a new way in studying the coupling between magnetic order and strain in BiFeO3 films. [ABSTRACT FROM AUTHOR]

We present a magnetic scanning microscope equipped with a nitrogen-vacancy (NV) center scanning probe that has the ability to mechanically tune the strain of soft matter in-situ. The construction of the microscope and a continuous strain-tuning sample holder are discussed. An optically detected magnetic resonance protocol utilized in the imaging is described. In order to show the reliability of this microscope, the strain conduction is estimated with finite element simulation, and x-ray diffraction is required for calibration when freestanding crystal films are under consideration. A magnetic imaging result is displayed to demonstrate the nano-scale imaging capability. The microscope presented in this work is helpful in studying strain-coupled magnetic physics such as magnetic phase transition under strain and strain-tuned cycloidal orientation tilting. [ABSTRACT FROM AUTHOR]

Energy efficiency is a critical issue in the management and operation of cloud data centers, which form the backbone of cloud computing. Virtual machine (VM) placement has a significant impact on energy-efficiency improvement for virtualized data centers. Among various methods to solve the VM-placement problem, the genetic algorithm (GA) has been well accepted for the quality of its solution. However, GA is also computationally demanding, particularly in the computation of its fitness function. This limits its application in large-scale systems or specific scenarios where a fast VM-placement solution of good quality is required. Our analysis in this paper reveals that the execution time of the standard GA is mostly consumed in the computation of its fitness function. Therefore, this paper designs a data structure extended from a previous study to reduce the complexity of the fitness computation from quadratic to linear one with respect to the input size of the VM-placement problem. Incorporating with this data structure, an alternative fitness function is proposed to reduce the number of instructions significantly, further improving the execution-time performance of GA. Experimental studies show that our approach achieves 11 times acceleration of GA computation for energy-efficient VM placement in large-scale data centers with about 1500 physical machines in size. [ABSTRACT FROM AUTHOR]

The formation of a nonlocal electron distribution function (EDF) in an argon dusty plasma of a dc glow discharge has been studied in a wide range of microparticle densities and their different spatial distributions inside a dusty cloud have also been explored. It is shown that the spatial profile of charges and the ambipolar potential can vary greatly, both with a change in the absolute values of the density of dust particles and the type of their spatial distribution. In turn, changes in the profiles of the ambipolar potential lead to strong differences in the nonlocal EDF at different points of the tube radius. This is most clearly seen at high densities of dust particles when nonmonotonic profiles of the potential distribution and reversal of the sign of the ambipolar field are formed. In this extreme case, great changes in the nonlocal EDF are observed not only at the discharge periphery but also inside the dust cloud. [ABSTRACT FROM AUTHOR]

[Display omitted] • Agglomerates exhibited superior Cr(VI) sequestration than its monomers. • Abundant positive charges of the agglomerates enhanced Cr(VI) sorption. • Monomers transformed Cr(VI) to Cr(OH) 3 , the agglomerates converted Cr(VI) to Cr 2 O 3. Aggregation of carbon nanoparticles (CNPs) exerts significant influence on its surrounding environment. To comprehensively evaluate their environmental impacts, it is essential to clarify the relationship between CNP monomers, agglomerates, and their sorption and photocatalysis behaviors. In this work, three agglomerates were prepared by crosslinking one-dimensional oxidized carbon nanotubes (OCNTs), quasi one-dimensional oxidized graphene ribbons (OGRs), and two-dimensional graphene oxide sheets (GOs) with polyacrylamide hydrochloride (PA). Notably, the sorption and photo-reduction behaviors of Cr(VI) are different on the surfaces of CNPs monomers and agglomerates. Overall, all the agglomerates demonstrated higher Cr(VI)-sequestration capacities than the corresponding monomers regardless of dark environment and light irradiation. For CNPs monomers, chromium species were scarcely adsorbed on the particle surface in the dark; the sunlight illumination promoted significantly the transformation of Cr(VI) ions to solid Cr(OH) 3 , resulting in sequestration capacities of 16.7, 47.7, and 115.4 mg/g in OCNTs, OGRs and GOs, respectively. After crosslinked by PA, the total sequestration capacity of Cr(VI) pollutants in the agglomerates increased by 3.4 ∼ 21.4 times compared to their corresponding monomers. It was noteworthy that the agglomerates almost converted all of Cr(VI) to Cr 2 O 3 under the illumination. This study highlights the discrepancies in Cr(VI)-sequestration behavior between CNPs and their agglomerates, which provides a novel insight into environmental impacts of CNPs and their agglomerates in nature. [ABSTRACT FROM AUTHOR]

This study presents a new method combining cold plasma-activated oxygen (CPAO) and microwave (MW) to decontaminate milkshake powder, exploring its effectiveness, mechanisms, and quality impact. CPAO (6 min) alone reduced bacterial load by 0.419 log CFU/g, and MW (3 min) by 0.030 log CFU/g. However, their co-application significantly amplified decontamination, achieving a 1.265 log CFU/g reduction. CPAO-MW co-treatment inflicted more oxidative damage on bacterial cell membranes and intracellular antioxidant defense system, leading to higher mortality. It also raised protein and lipid oxidation, while decreasing vitamin C and A levels in the powder. Specifically, CPAO (6 min)-MW (3 min) co-treatment increased the carbonyl content from 0.438 to 0.891 nmol/mg protein, malondialdehyde from 0.824 to 0.996 mg/kg, and lowered vitamin C from 162.151 to 137.640 mg/kg, and vitamin A from 2.05 to 1.38 mg/kg. This study shows CPAO-MW is effective for decontaminating powdered foods but highlights a need to reduce negative effects. [Display omitted] • Microwave boosted CPAO's ability to decontaminate microbes in milkshake powder. • CPAO-MW caused oxidative damage to the cell membrane and antioxidant defense system. • CPAO-MW led to a certain oxidation of the main nutrients in milkshake powder. [ABSTRACT FROM AUTHOR]

• A novel multiscale topology optimization method is proposed for designing asymmetric porous sandwich structures. • Multi-material sandwich structures are topologically optimized using the proposed method. • The thickness and material of two face sheets and the configuration of composite cores are simultaneously optimized. • Parametric level set method and alternating active-phase method are adopted. • Several 2D and 3D numerical examples are investigated and compared. Compared with conventional symmetric sandwich structure with identical face sheets and single-material core, asymmetric porous sandwich structures (APSSs), which are composed of unidentical face sheets and composite core, usually take better advantage of all materials and provide superior bending stiffness. However, current studies regarding the APSSs are mainly analytical- and experimental-based methods with predefined face sheet thicknesses and core configurations, which greatly confines the potential loading capacity of sandwich structures. This paper develops a multiscale topology optimization method for the multi-material APSSs, which can realize the designs of the thickness and material of two face sheets at macroscale as well as the configuration of composite cores at microscale for minimizing structural compliance. Firstly, at macroscale, a multi-material variable thickness sheet method integrated with an alternating active-phase algorithm are employed to optimize the thickness and material of two solid face sheets. Then, at microscale, a difference-set-based multi-material level set (DS-MMLS) model is applied to represent the topology of each material phase within sandwich core, and their topological evolution can be readily achieved by using a parametric level set method also combined with the alternating active phase algorithm. Several 2D and 3D numerical examples are provided to show the effectiveness and advantages of the proposed method. The results indicate that compliances of the optimized APSSs show superior advantages over some conventional sandwich structures with predefined design features. [ABSTRACT FROM AUTHOR]

Design sensitivity analysis (DSA) of transient responses, which are indispensable in gradient-based time domain optimization, often requires excessive computational resources for viscoelastically damped systems to directly differentiate and integrate the full-order model (FOM). In this paper, an efficient model-order reduction (MOR)–based DSA framework is developed for capturing the 1st- and 2nd-order derivatives of the transient responses and response functions for viscoelastically damped systems. The damping force is represented by a non-viscous damping model, which depends on the past history of motion via convolution integrals over suitable kernel functions. The direct differentiation method (DDM) is used to derive the DSA. Three robust modal reduction bases, namely multi-model (MM) method, modal strain energy modified by displacement residuals (MSER) method and improved approximation method (IAM) are introduced to reduce the system dimension. Based on a generalized damping model in expression of fraction formula, a reduced state-space formulation without convolution integral term is derived. The 1st- and 2nd-order derivatives of the transient responses and response functions are calculated using a modified precise integration method and the DDM on the reduced stage. The computational efficiency and accuracy of the presented methods are illustrated and compared by two examples. The results indicate that the computational time is significantly reduced by the proposed MOR methods maintaining fairly good accuracy. Among these methods, the MM method represents the most compromise between precise and efficiency and would be the best candidate to be the reduction basis for calculating the time domain DSA of large-scale viscoelastically damped systems. [ABSTRACT FROM AUTHOR]

The Saint-Venant equations can be used to describe the confluence process of unsteady flows in open channels. In largescale hydrological simulation software, solving the numerical solution of the equations is the biggest bottleneck restricting the running time of the program. This paper analyzes the structure of the serial solving program and the hotspots of calculation, and explores the parallelism of the singe-step simulation loop calculation section and instruction arrangement in the calculation intensive program. A master slave asynchronous parallel scheme is designed for the heterogeneous manicure architecture of the SunwaytTaihuLight supercomputer. The solver is ported, paired and accelerated based on MPI and thread libraries. SIMD technology is used to vectorize the slavecore's calculation section, and doubts buffering strategies are used to optimize the communication process. The tests show that the performance of hot functions can be increased by more than 3 times on average compared with the computation before optimization. Within a million-unit scale, the speedup of parallel programs using manicure optimization can maintain growing linearly, which shows strong scalability in Sunway's multi-nodes. [ABSTRACT FROM AUTHOR]

In the present study, the machine learning algorithm is utilized for the first time to improve the probe diagnosis. Machine learning methods are utilized to improve the Langmuir probe diagnostic accuracy and the diagnosable plasma parameter range without changing the probe structure based on the Langmuir probe. They provide a new way for experimentally obtaining electron density. A DC glow discharge simulation model and experimental equipment are established. Utilizing the discharge pressure and voltage as independent variables, the simulation and experimental electron densities are collected, the simulation and experimental data are utilized for training, and the plasma electron density outside of the pressure and voltage range of the training data is predicted, thereby achieving the prediction. Simultaneously, when the data amount is large enough, even without experimental measurement, the electron density can be obtained directly through the input parameters, without relying on the plasma physical model. [ABSTRACT FROM AUTHOR]

The spatial distribution of dust particles in a low-pressure homogeneous positive column of a dc glow discharge in a right-angle curved (V-shaped) glass tube in different spatial orientations was observed and analyzed. It is found that in all cases, the ambipolar field prevents charged dust particles from falling on the wall of the glass tube. As a result, the design of the curved glass tube makes it possible to create in practice a simple and effective ambipolar trap and to implement the collection and control of dust particles in plasma. [ABSTRACT FROM AUTHOR]

Exploring and revealing the secret of the function of the human brain has been the dream of mankind and science. Delineating brain transcriptional regulation has been extremely challenging, but recent technological advances have facilitated a deeper investigation of molecular processes in the brain. Tracing the molecular regulatory mechanisms of different gene expression profiles in the brain is divergent and has made it possible to connect spatial and temporal variations in gene expression to distributed properties of brain structure and function. Here, we review the molecular diversity of the brain among rodents, non-human primates and humans. We also discuss the molecular mechanism of non-coding DNA/RNA at the transcriptional/post-transcriptional level based on recent technical advances to highlight an improved understanding of the complex transcriptional network in the brain. Spatiotemporal and single-cell transcriptomics have attempted to gain novel insight into the development and evolution of the brain as well as the progression of human diseases. Although it is clear that the field is developing and challenges remain to be resolved, the impressive recent progress provides a solid foundation to better understand the brain and evidence-based recommendations for the diagnosis and treatment of brain diseases. [ABSTRACT FROM AUTHOR]

Energy efficiency is a critical issue in the management of data centers, which form the backbone of cloud computing. Virtual resource management has a significant impact on improving the energy efficiency of data centers. Despite the progress in this area, virtual resource management has been considered mainly at two separate levels: application assignment and virtual machine placement. It has not been well-investigated in a unified framework for both levels, limiting further improvement in the energy efficiency of data centers. To address this issue, this paper proposes the virtual resource management problem for energy efficiency as a constrained optimization problem. Then, this paper simplifies the problem through profile-guided task classification and problem decomposition for complexity reduction and improved energy efficiency. After that, a three-phase framework and algorithms are presented for profiling and profile updating, task classification and application assignment, and successive virtual machine placement. Experimental studies show energy savings of 8–12% by the three-phase framework compared to the existing technique. [ABSTRACT FROM AUTHOR]

Experiments were carried out in dusty plasmas of both the stratified and homogeneous positive columns (PCs) in a U-shaped discharge tube during its rotation from the vertical to the horizontal position. It is shown that in all cases the radial ambipolar field prevents charged dust particles from falling on the tube walls. For a vertically oriented tube, a dust cloud is observed only in a strong field of strata and is absent in a homogeneous plasma. In a horizontally oriented tube, the dust particles drift toward the anode in an axial external field. In this case, dust particles are trapped at the point of transition from the horizontal to the vertical section of the tube, in both the stratified and homogeneous PCs. It was concluded that for a V-shaped design of a cylindrical tube, an ambipolar dust trap, which is simple in technical execution, can be implemented, which makes it possible to hold dust particles in its lower part. [ABSTRACT FROM AUTHOR]

Highlights • The first and second derivatives for the transient response of non-viscously damped systems are calculated. • The direct differentiate method is adopted. • The sensitivities are derived by using a modified precise integration method. • The computational considerations of the methods are investigated and compared. • Two numerical examples are given to show the performances of the method. Abstract Calculation of the first and second derivatives of transient response with respect to design variables is a prerequisite when gradient-based methods are adopted for optimization design in time-domain. In this paper, a design sensitivity analysis (DSA) method for calculating the first and second derivatives of the transient response for non-viscously damped systems is developed. The assumed damping forces depend on the past history of motion via convolution integrals over some kernel functions. The direct differentiate method (DDM) is selected to derive the DSA method. By introducing a generalized damping model in expression of fraction formula, the equations of motion of the non-viscously damped system are transformed into a state-space form without the convolution integral terms. Then, the first and second derivatives of the transient response are formulated based on a modified precise integration method using the DDM. The numerical stability, accuracy and implementation effort of the DDM are discussed. Two numerical examples are comparatively demonstrated using the DDM, the discretize-then-differentiate adjoint variable method (AVM) and the differentiate-then-discretize AVM. The results indicate that, by considering all the computational considerations, the proposed DDM is more suitable than the other two methods for the sensitivity analysis of transient response for non-viscously damped systems. Besides, it is also the only existing method to capture the second-order derivatives of transient response for the non-viscously damped systems. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Comparison study on 5 regioisomeric pyrene dyes indicate the regio-effect with an order of 1-pyrenyl > 4-pyrenyl > 2-pyrenyl. • 4-Substituted isomer demonstrated exceptionally large Stokes shift and high fluorescence quantum yield. • Preliminary fluorescent cell imaging indicated these pyrene cationic dyes could be active mitochondrial probes. Abstract Two series of regioisomeric mono-substituted far-red fluorescent pyrene-indolium and pyrene-pyridinium conjugated dyes were synthesized, and their structures were ambiguously determined by single crystal X-ray diffractions. The photophysical properties of these pyrene-containing dyes in several solvents were investigated to figure out the modulation by changing the site of substituent on the pyrene moiety. The 4-substituted pyrene dyes Py-4 and PP-4 exceptionally demonstrated remarkable fluorescence quantum yield and much larger Stokes shift than their regioisomers (Δ ṽ of PP-4 is 7732 cm−1 in acetonitrile). Preliminary cell staining and fluorescent imaging experiments indicated that t -Bu-Py-4 could be used as mitochondrial probe with good selectivity and low cytotoxicity. [ABSTRACT FROM AUTHOR]

In this paper, design sensitivity analysis methods for the transient response of non-viscously damped systems are considered. The damping forces of the non-viscously damped systems depend on the past history of motion via convolution integrals over some suitable kernel functions. The adjoint variable method (AVM) is adopted to develop the design sensitivity analysis. Two numerical solution schemes, namely the discretize-then-differentiate method and the differentiate-then-discretize method, are introduced to complete the AVM for the sensitivity analysis of non-viscously damped systems. The discretize-then-differentiate AVM discretizes the equations of motion based on the Newmark- β implicit integration method first and then differentiates the discrete equations. On the contrary, the differentiate-then-discretize AVM firstly differentiates the equations of motion after transforming it into a state-space form, and then discretizes the equations based on a modified precise integration method (PIM). The numerical accuracy, efficiency, consistency and implementation effort are discussed and compared. Two numerical examples are presented to show the effectiveness of both methods. The results indicate that, by considering both computational accuracy and efficiency, the PIM based differentiate-then-discretize method is more suitable than the Newmark- β based discretize-then-differentiate method for the sensitivity analysis of transient responses for non-viscously damped systems. [ABSTRACT FROM AUTHOR]

Two regioisomeric phenalenocarbazoles have been synthesized by direct reductive cyclization of 2′-Nitrophenyl-pyrene isomers respectively. Their photophysical properties and crystal structures as well as CV properties were investigated and compared with those of sulfur containing analogues. Although the fluorescence emission properties of 1N are very similar with those of 2N , the HOMO energy level of 1N is 0.16 eV higher than that of 2N indicating that 1N has better electron donating ability. [ABSTRACT FROM AUTHOR]

Large and complex engineering systems are usually assembled by subcomponents with different energy dissipation levels. Therefore, these systems often contain multiple damping models, which may lead to great difficulties in analyzing efficiently. In this paper, an efficient modal projection-based reduction method, which accounts for transient dynamic responses of structural system with multiple damping models, is proposed in the framework of a modified precise integration method. Two robust modal reduction bases, namely multi-model method (MM) and modal strain energy by first-order correction method (MSEC), are introduced to reduce the order of the original system. Based on the reduced system and a general damping model (GDM), a reduced state-space formalism for the structural system with multiple damping models is developed. Finally, the transient dynamic responses are derived using a modified precise integration method on the reduced stage. The numerical stability, accuracy and complexity are discussed. Two numerical examples are illustrated to assess the performances of the computational accuracy and efficiency. The results indicate that the proposed method is more efficient than other methods and most suitable for large-scale problems with rather good accuracy. [ABSTRACT FROM AUTHOR]

Sophisticated engineering systems are usually assembled by subcomponents with significantly different levels of energy dissipation. Therefore, these damping systems often contain multiple damping models and lead to great difficulties in analyzing. This paper aims at developing a time integration method for structural systems with multiple damping models. The dynamical system is first represented by a generally damped model. Based on this, a new extended state-space method for the damped system is derived. A modified precise integration method with Gauss-Legendre quadrature is then proposed. The numerical stability and accuracy of the proposed integration method are discussed in detail. It is verified that the method is conditionally stable and has inherent algorithmic damping, period error and amplitude decay. Numerical examples are provided to assess the performance of the proposed method compared with other methods. It is demonstrated that the method is more accurate than other methods with rather good efficiency and the stable condition is easy to be satisfied in practice. [ABSTRACT FROM AUTHOR]

Data mining techniques are applied to identify hidden patterns in large amounts of patient data. These patterns can assist physicians in making more accurate diagnosis. For different physical conditions of patients, the same physiological index corresponds to a different symptom association probability for each patient. Data mining technologies based on certain data cannot be directly applied to these patients’ data. Patient data are sensitive data. An adversary with sufficient background information can make use of the patterns mined from uncertain medical data to obtain the sensitive information of patients. In this paper, a new algorithm is presented to determine the top K most frequent itemsets from uncertain medical data and to protect data privacy. Based on traditional algorithms for mining frequent itemsets from uncertain data, our algorithm applies sparse vector algorithm and the Laplace mechanism to ensure differential privacy for the top K most frequent itemsets for uncertain medical data and the expected supports of these frequent itemsets. We prove that our algorithm can guarantee differential privacy in theory. Moreover, we carry out experiments with four real-world scenario datasets and two synthetic datasets. The experimental results demonstrate the performance of our algorithm. [ABSTRACT FROM AUTHOR]

Clarifying the reaction process and specific mechanism between variable-valence elements and oxidized carbon nanoparticles is essential to evaluate the environmental impact of carbon nanomaterials. In this study, the photocatalytic reduction of Cr(VI) on oxidized carbon nanotubes (OCNTs), oxidized graphene ribbons (OGRs), and graphene oxide sheets (GOs) was explored by batch experiments and spectroscopic analyses. The reaction efficiencies strongly depended on the number of oxygenated groups in the oxidized carbon nanoparticles. The abundant oxygenated groups enabled the GOs to exhibit the highest photocatalytic activity, followed by the OGRs and OCNTs. As a result, the photoreduction efficiency of Cr(VI) reached 96% for GOs, whereas those of OGRs and OCNTs were only 40% and 13%, respectively. In addition, different types of oxygenated groups exhibited various activities based on molecular model tests, following the sequence carboxylic > hydroxyl > carbonyl > ether > aldehyde > edge. Based on the underlying relationship between the oxygenated groups, topological structures, and mechanical strain in the carbon nanoparticles, we speculate that mechanical strain plays a critical role in the formation of oxygenated groups, thereby regulating their photocatalytic activities. The findings in this work provide novel insights into the roles of oxygenated groups and the mechanical strain of carbon nanoparticles in their environmental behavior. [Display omitted] • Carbon nanoparticles with abundant oxygenated groups showed the superior photoreduction efficiency of Cr(VI). • The characteristic oxygenated groups represented distinct photoactivities. • The underlying relationship between oxygenated groups and mechanical strains regulated photocatalytic behavior of carbon nanoparticles. [ABSTRACT FROM AUTHOR]

[Display omitted] • A level set-based multi-material topological design method is proposed for multiphase micro-architectured materials. • A difference-set-based level set model is combined with an alternating active-phase algorithm to facilitate the extension to more phases. • Optimized topologies of multiphase micro-architectured materials are featured with smooth boundaries and distinct interfaces. • Both numerical examples and additive-manufactured specimens demonstrate the effectiveness of the proposed method. Micro-architectured materials with periodically configured microstructures are widely used in various engineering fields due to their superior mechanical properties. Compared with conventional topology design with one single material, topological design with multiple materials can provide a better solution as the expanded design freedom. This paper presents a level set-based multi-material topological design method for micro-architectured materials involving three phases or more. In this method, a difference-set-based multi-material level set model is employed to represent the topology of each phase, in which N + 1 phases can be precisely represented by the sequential difference-set of N level set functions without any overlaps and redundant regions. By using an alternating active-phase algorithm, the multi-material topology design problem with N + 1 phases is splitted into N (N + 1)/2 binary-phase topological design sub-problems, where each sub-problem involves fewer design variables and volume constraints. The effective properties of multiphase micro-architectured materials are evaluated by a numerical homogenization approach, and their topological evolutions of two active phases in each sub-problem can be readily achieved by updating a single level set function, which greatly facilitate the extension to topological design problems with more phases. Both numerical examples and additive-manufactured specimens demonstrate the effectiveness of the proposed method for designing multiphase micro-architectured materials. [ABSTRACT FROM AUTHOR]

Engineering structures are often assembled by subsections with various levels of energy dissipation, which lead to great difficulties in analyzing. In this paper, a direct time integration method is proposed to solve the dynamic responses of structural systems involving multiple nonviscous damping models. Based on a general non-viscously damped model, an extended state-space scheme for the damped system is derived. Then, an implicit time integration method using linear approximations is developed built on the extended state-space formalism. The stability and efficiency of the method are discussed by theoretical and numerical analyses. The method is illustrated by two examples. [ABSTRACT FROM AUTHOR]

The analysis of large, complex systems can be simplified and more computationally efficient if smaller, simpler subcomponents can be treated and assembled. Component Mode Synthesis (CMS) methods allow one to reduce the order of the model at the subcomponent level. Although CMS methods are widely applied in the field of structure dynamics for undamped or viscously damped systems, their counterparts for viscoelastically damped systems seem not well-developed. Motivated by such points, this paper develops a model-order-reduction approach for viscoelastically damped systems based on a free interface CMS method. Due to the fact that the nonviscous modes and higher-order elastic modes are difficult to be obtained accurately for viscoelastic systems, the mode truncation error is often introduced. To reduce the mode truncation error problem, two residual attachment modes of viscoelastically damped systems are proposed in terms of the lower modes and system matrices by using the first one or two terms of Neumann expansion. Finally, three numerical studies are provided to illustrate the accuracy and effectiveness of the derived methods. It is shown that the proposed methods can receive good results and reduce the modal truncation error significantly over the conventional method. [ABSTRACT FROM AUTHOR]

Background: Postoperative sleep disturbance (PSD) is a prevalent clinical complication that may arise due to various factors. The purpose of this investigation is to identify the risk factors for PSD in spinal surgery and establish a risk prediction nomogram. Methods: The clinical records of individuals who underwent spinal surgery from January 2020 to January 2021 were gathered prospectively. The least absolute shrinkage and selection operator (LASSO) regression, along with multivariate logistic regression analysis, was employed to establish independent risk factors. A nomogram prediction model was devised based on these factors. The nomogram's effectiveness was evaluated and verified via the receiver operating characteristic (ROC) curve, calibration plot, and decision curve analysis (DCA). Results: A total of 640 patients who underwent spinal surgery were analyzed in this investigation, among which 393 patients experienced PSD with an incidence rate of 61.4%. After conducting LASSO regression and logistic regression analyses using R software on the variables in training set, 8 independent risk factors associated to PSD were identified, including female, preoperative sleep disorder, high preoperative anxiety score, high intraoperative bleeding volume, high postoperative pain score, dissatisfaction with ward sleep environment, non-use of dexmedetomidine and non-use of erector spinae plane block (ESPB). The nomogram and online dynamic nomogram were constructed after incorporating these variables. In the training and validation sets, the area under the curve (AUC) in the receiver operating characteristic (ROC) curves were 0.806 (0.768–0.844) and 0.755 (0.667–0.844), respectively. The calibration plots indicated that the mean absolute error (MAE) values in both sets were respectively 1.2% and 1.7%. The decision curve analysis demonstrated the model had a substantial net benefit within the range of threshold probabilities between 20% and 90%. Conclusions: The nomogram model proposed in this study included eight frequently observed clinical factors and exhibited favorable accuracy and calibration. Trial registration: The study was retrospectively registered with the Chinese Clinical Trial Registry (ChiCTR2200061257, 18/06/2022). [ABSTRACT FROM AUTHOR]

In order to precaution known and unknown attack of RFID technology, this paper proposed multi-decision tree model based on the analysis of RFID security protocol to check the intrusion behavior. By the analysis of the multi-decision tree model, the model can find the relationship of different attack of RFID technology. And the model has the advantage of extensibility and high efficiency, which make the multi-decision tree model suitable for all practical application of RFID system. [ABSTRACT FROM AUTHOR]

• The first and second derivatives for PSD function subject to stochastic excitations are derived. • The proposed methods are applicable to non-classically damped systems. • The highly efficient Pseudo-Excitation-Method (PEM) is adopted. • Two correction methods are developed without the need to calculate the eigen-sensitivities. • Computational accuracy is greatly improved by considering truncated high-order complex modes. Calculating the first and second derivatives of Power Spectrum Density (PSD) function with respect to various design variables is a prerequisite for random responses when gradient-based algorithms are adopted. This paper presented two numerical methods to capture the sensitivity and Hessian matrix of the PSD function for non-classically damped systems subject to stationary stochastic excitations. The direct differentiate method (DDM) is adopted to develop the design sensitivity analysis (DSA). By using Pseudo-Excitation Method (PEM), the governing equations of the non-classically damped system subject to stationary stochastic excitations are transformed into a corresponding deterministic harmonic response problem. Then, the first and second derivatives of the PSD function are given in detail using the DDM. Two numerical methods, namely PEM-modal displacement method (MDM) and PEM-hybrid expansion method (HEM), are proposed to compute the sensitivity and Hessian matrix of the PSD function. The computational accuracy and efficiency of both methods are discussed and compared theoretically and numerically by two illustrations. The results indicate that both methods are valid for the DSA of the PSD function for non-classically damped systems and the PEM-HEM is more suitable than the PEM-MDM with all computational considerations. [ABSTRACT FROM AUTHOR]

Purpose: To study the relationship between fluorodeoxyglucose (FDG) uptake in pulmonary tissue after radical radiation therapy (RT) and the presence and severity of radiation pneumonitis. Methods and Materials: In 88 consecutive patients, 18F-FDG–positron emission tomography was performed at a median of 70 days after completion of RT. Patients received 60 Gy in 30 fractions, and all but 15 had concurrent platinum-based chemotherapy. RT-induced pulmonary inflammatory changes occurring within the radiation treatment volume were scored, using a visual (0 to 3) radiotoxicity grading scale, by an observer blinded to the presence or absence of clinical radiation pneumonitis. Radiation pneumonitis was retrospectively graded using the Radiation Therapy Oncology Group (RTOG) scale by an observer blinded to the PET radiotoxicity score. Results: There was a significant association between the worst RTOG pneumonitis grade occurring at any time after RT and the positron emission tomograph (PET) radiotoxicity grade (one-sided p = 0.033). The worst RTOG pneumonitis grade occurring after the PET scan was also associated with the PET radiotoxicity grade (one-sided p = 0.035). For every one-level increase in the PET toxicity scale, the risk of a higher RTOG radiation pneumonitis score increased by approximately 40%. The PET radiotoxicity score showed no significant correlation with the duration of radiation pneumonitis. Conclusions: The intensity of FDG uptake in pulmonary tissue after RT determined using a simple visual scoring system showed significant correlation with the presence and severity of radiation pneumonitis. 18F-FDG–PET may be useful in the prediction, diagnosis and therapeutic monitoring of radiation pneumonitis. [ABSTRACT FROM AUTHOR]

Abstract: Numerous studies support a role for the endogenous 5-hydroxytryptamine (5-HT) system in the hypothermic effect of capsaicin. None of those studies, however, selectively delineate a role for 5-HT reuptake or 5-HT receptors in this regard. In the present investigation, we determined if the blockade of 5-HT reuptake or the activation of 5-HT1A or 5-HT2 receptors modulates capsaicin-evoked hypothermia. The administration of capsaicin (0.2–1mg/kg, i.m.) produced dose-related hypothermia. Fluoxetine (10mg/kg, i.p.), a selective serotonin reuptake inhibitor (SSRI), did not affect body temperature. For combined administration, pretreatment with fluoxetine (10mg/kg, i.p.) significantly attenuated the hypothermia caused by capsaicin (0.5 and 1mg/kg, i.m.). For the 5-HT receptor experiments, we pretreated rats with either WAY 100635, a 5-HT1A receptor antagonist, or mianserin, a 5-HT2 receptor antagonist, and then administered a fixed, hypothermic dose of capsaicin (1mg/kg, i.m.). WAY 100635 (1mg/kg, s.c.) administration did not affect capsaicin-evoked hypothermia. This indicates that 5-HT1A receptor activation does not play a major role in the hypothermic effect of capsaicin. In contrast, pretreatment with mianserin (10mg/kg, i.p.) enhanced the hypothermic effect of capsaicin (1mg/kg, i.m.). The present data reveal that capsaicin-evoked hypothermia in rats is attenuated by the blockade of 5-HT reuptake and enhanced by the antagonism of 5-HT2 receptors. [Copyright &y& Elsevier]

Abstract: Icilin (AG-3-5) is a cold-inducing agent that activates the transient receptor potential channels TRPM8 and TRPA1. Both channels are members of the transient receptor potential (TRP) superfamily of ion channels and are activated by cold. Despite the key role of cold-activated TRPM8 and TRPA1 channels in temperature sensation and other physiological processes, the significance of these channels in thermoregulation in conscious animals is poorly understood. Therefore, in the present study we investigated the effects of icilin on body temperature in rats and tested the hypothesis that cold-activated TRP channel activation by icilin causes a hyperthermia which requires nitric oxide (NO) production and NMDA receptor stimulation. Our experiments revealed that icilin (2.5, 5, 7.5 and 10 mg/kg, i.m.) elicits a dose-related hyperthermia that is rapid in onset and of long duration. Pretreating rats with N G-nitro-l-arginine methyl ester hydrochloride (l-NAME) (10, 25 and 50 mg/kg, i.p.), a non-selective NO synthase inhibitor, attenuated the hyperthermia associated with icilin (7.5 mg/kg, i.m.). Pretreatment with (−)-6-[phosphonomethyl-1,2,3,4,4a,5,6,7,8,8a-decahydro-isoquinoline-2-carboxylate] (LY 235959) (0.25, 0.5 and 1 mg/kg, i.p.), a selective NMDA receptor antagonist, also attenuated the icilin-evoked hyperthermia. The administration of icilin (5 and 100 μg) into the lateral cerebroventricle of rats did not affect body temperature, thus indicating a peripheral site of action. These results indicate that icilin, a TRPM8/TRPA1 agonist, produces a dose-related hyperthermia in rats which requires both NO production and NMDA receptor activation. [Copyright &y& Elsevier]

Summary: The terminology used to characterize agonist action in preclinical studies requires careful application based on fundamental concepts of receptor theory. Especially important in this regard are the terms ‘intrinsic activity’, ‘efficacy’ and ‘full-’ or ‘partial-’ agonist. Failure to apply or interpret these terms properly can lead to erroneous prediction or perception of a compound''s clinical utility. This is illustrated here in reporting our recent antinociceptive studies with buprenorphine. Buprenorphine has been classified in some preclinical studies as a ‘partial agonist’, but there is now clear evidence using PET technology that buprenorphine can produce analgesia at less than full receptor occupancy, the definition of a ‘full agonist’, and that its analgesic effectiveness extends to cancer and neuropathic pain. We measured buprenorphine-induced antinociceptive time-course and dose-response curves in the same test (tail-dip/flick in mice) at three stimulus intensities: 48, 55, and 65°C. Buprenorphine antinociception was inversely related to stimulus intensity, producing 100% antinociception at 48°C. The dose-response curve was curvilinear (bell-shaped) at each temperature. The current results demonstrate the necessity of defining threshold criteria with the use of the term ‘full agonist’ and, more generally, highlight the importance of careful and accurate use of, and predictions based upon, the terms ‘intrinsic activity’, ‘efficacy’, and ‘full-’ or ‘partial-’ agonist. [Copyright &y& Elsevier]

Abstract: The present study investigated the effect of a drug combination of capsaicin and l-NAME on hypothermia in rats. Capsaicin administration (0.1, 0.25, 0.5, 1 and 2mg/kg, i.m.) caused a significant hypothermia. l-NAME (50mg/kg, i.p.), a nonspecific nitric oxide synthase (NOS) inhibitor, was ineffective. For combined administration, progressively increasing doses of capsaicin (0.1, 0.25, 0.5, 1 and 2mg/kg, i.p.) were given with a non-hypothermic dose of l-NAME (50mg/kg, i.p.). Experiments revealed that l-NAME (50mg/kg, i.p.) enhanced the hypothermic response to capsaicin (0.25, 0.5, 1, and 2mg/kg, i.m.). Comparison of the graded dose–effect curves for capsaicin alone and capsaicin plus l-NAME revealed a significant difference (P <0.05), thus indicating synergy for the drug interaction. To determine if l-NAME acted centrally, a fixed dose of l-NAME (1mg/rat, i.c.v.) was given with graded doses of capsaicin (0.25, 0.5, 1, and 2mg/kg, i.m.). l-NAME (1mg/rat, i.c.v.) only enhanced the hypothermia at a single dose of capsaicin (0.5mg/kg, i.m.). The super-additive hypothermia produced by the concurrent administration of capsaicin and l-NAME (50mg/kg, i.p.) is the first evidence of synergy for a drug combination of capsaicin and a NOS inhibitor. The synergy is apparent only when l-NAME is given systemically, thus indicating that the inhibition of peripheral NO production enhances the hypothermic response to capsaicin. [Copyright &y& Elsevier]

Abstract: AM 404 inhibits endocannabinoid uptake and enhances the cannabinoid CB1-mediated effects of endogenous cannabinoids. Accumulating evidence also suggests that AM 404 acts at sites other than the endocannabinoid system. One site is the transient receptor potential vanilloid 1 cation channel (TRPV1). A useful endpoint for discriminating between TRPV1- or CB1-mediated effects of AM 404 is hypothermia. This is because TRPV1 or CB1 receptor activation produces a significant hypothermia in rats. The present study investigated the effects of AM 404 (1, 5, 10 and 20 mg/kg, i.p.) on body temperature in rats and the involvement of TRPV1 and CB1 receptors in the effects of AM 404. Doses of 10 and 20 mg/kg of AM 404 produced significant hypothermia. Pre-treatment with capsazepine (30 mg/kg, i.p.) blocked the hypothermia caused by 10 and 20 mg/kg of AM 404. Pre-treatment with SB 366791 (2 mg/kg, i.p.), a new TRPV1 antagonist, also abolished the hypothermia evoked by AM 404 (20 mg/kg, i.p.). In contrast, pre-treatment with SR 141716A (Rimonabant), a CB1 antagonist, or AA-5-HT, a fatty acid amide hydrolase (FAAH) blocker, did not affect AM 404-evoked hypothermia. The present data demonstrate that AM 404 evokes a significant hypothermia in rats that is dependent on TRPV1 receptor activation. [Copyright &y& Elsevier]

Abstract: The present study investigated a potential role for cannabinoid CB1 and CB2 receptors in capsaicin-evoked hypothermia. Capsaicin (1 mg/kg, s.c.) caused rapid and significant hypothermia in rats. Pretreatment with SR 141716A (1, 2.5 and 5 mg/kg, i.p.), a CB1 antagonist, or SR 144528 (1, 2.5 and 5 mg/kg, i.p.), a CB2 antagonist, did not affect capsaicin-induced hypothermia. In separate experiments, the hypothermia caused by WIN 55212-2 (5 mg/kg, i.m.), a cannabinoid agonist, was not significantly altered by capsazepine (10 and 30 mg/kg, i.p.) or SB 366791 (2 mg/kg, i.p.), a novel TRPV1 antagonist. These data suggest that capsaicin causes hypothermia by a CB1- and CB2-independent mechanism, and that WIN 55212-2 causes hypothermia by a TRPV1-independent mechanism. [Copyright &y& Elsevier]

ICI 204448, a selective κ-opioid agonist with limited CNS access, can be used to discriminate central and peripheral opioid actions on physiological systems such as pain and thermoregulation. Therefore, we investigated the effect of ICI 204448 (2.5, 5, and 10 mg/kg, s.c.) on male Sprague-Dawley rats exposed to ambient temperatures of 5, 20, or 32°C. ICI 204448 did not alter the body temperature of rats maintained at 20 or 32°C. However, 5 and 10 mg/kg of ICI 204448 evoked significant hypothermia in rats exposed to 5°C. The i.c.v. administration of nor-BNI, a κ-opioid antagonist, did not affect the hypothermia produced by the systemic injection of ICI 204448. Thus, an involvement of brain κ-opioid receptors in ICI 204448-evoked hypothermia is unlikely. The present data demonstrate for the first time that ICI 204448 produces hypothermia in cold-exposed rats and suggest that the role of peripheral κ-opioid receptors in thermoregulation becomes more significant at cold ambient temperatures. Copyright © 2005 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Infrared (IR) spectroscopy using a smart endurance single bounce diamond attenuated total reflection (ATR) cell has been used to study the changes in the spectra of the surfactant octadecyltrimethylammonium (ODTMA) bromide upon intercalation into a sodium montmorillonite. The wavenumbers of bands attributed to CH-stretching and CH-bending vibrations, in general, decrease as the concentration of the surfactant measured in terms of the cation exchange capacity (CEC) up to 1.0 CEC. After this point, the bands increase approaching a value the same as that of the surfactant. Significant changes occur in the HCH deformation modes of the methyl groups of the surfactant. These changes are attributed to the methyl groups locking into the siloxane (SiO) surface of the montmorillonite. Such a concept is supported by changes in the SiO-stretching bands of the montmorillonite siloxane surface. [Copyright &y& Elsevier]

X-ray diffraction has been used to study the changes in the surface properties of a montmorillonitic clay through the changes in the basal spacings of montmorillonite (SWy-2) and surfactant-intercalated organoclays. Variation in the d-spacing was found to be a step function of the surfactant concentration. High-resolution thermogravimetric analysis (HRTG) shows that the thermal decomposition of SWy-2-MMTs modified with the surfactant octadecyltrimethylammonium bromide takes place in four steps. A mass-loss step is observed at room temperature and is attributed to dehydration of adsorption water. A second mass-loss step is observed over the temperature range 87.9 to 135.5 °C and is also attributed to dehydration of water hydrating metal cations such as Na+. The third mass loss occurs from 178.9 to 384.5 °C and is assigned to a loss of surfactant. The fourth mass-loss step is ascribed to the loss of OH units through dehydroxylation over the temperature range 556.0 to 636.4 °C. A model is proposed in which, up to 0.4 CEC, a surfactant monolayer is formed between the montmorillonitic clay layers; up to 0.8 CEC, a lateral-bilayer arrangement is formed; and above 1.5 CEC, a pseudotrimolecular layer is formed, with excess surfactant adsorbed on the clay surface. [Copyright &y& Elsevier]

In this work, ferrate(VI) was generated by the electrochemical oxidation of porous magnetite electrodes, made by melting pure magnetite grains. Pretreatment of the anode by cathodic polarization was necessary for ferrate(VI) generation and the achievement of high current efficiency. A electrolyte composition was found to be 16 M NaOH. In this electrolyte, the effect of anode current density J on Fe(VI) synthesis rate, current efficiency, and internal cell temperature were studied. An optimum result was obtained at J=3.3 mA cm-2, 30 °C in 16 M NaOH for 5 h. [Copyright &y& Elsevier]

The thermal decomposition of syngenite, K2Ca(SO4)2·H2O, formed during the treatment of liquid manure has been studied by thermal gravimetric analysis, differential scanning calorimetry, high temperature X-ray diffraction (XRD) and infrared emission spectroscopy (IES). Gypsum was found as a minor impurity resulting in a minor weight loss due to dehydration around 100 °C. The main endothermic dehydration and decomposition stage of syngenite to crystalline K2Ca2(SO4)3 and amorphous K2SO4 is observed around 200 °C. The reaction involves a solid-state re-crystallisation, while water and the K2SO4 diffuse out of the existing lattice. The additional weight loss steps around 250 and 350 °C are probably due to presence of larger syngenite particles, which exhibit slower decomposition due to the slower diffusion of water and K2SO4 out of the crystal lattice. A minor endothermic sulphate loss around 450 °C is not due to the decomposition of syngenite or its products or of the gypsum impurity. The origin of this sulphate is not clear. [Copyright &y& Elsevier]

Copper was adsorbed onto Ca-exchanged montmorillonite (Cheto clay) under basic conditions. Differential thermogravimetric analysis (DTGA) combined with mass spectroscopy (MS) was employed as the principal technology to study the distributions and structures of adsorbed copper species on Cheto clay. The results showed that the original Cheto clay was easily rehydrated. After copper adsorption, a step-by-step replacement of hydrated calcium ions by copper–ammonia complex was observed through the gradual decrease of the first DTGA dehydration peak intensity with the increasing copper loading amount. Compared with the original Cheto clay, copper-loaded samples showed new DTGA peaks assigned to NH3 and N2O. The presence of N2O peak suggested that the loaded copper species were in agglomerated copper oxide form, which dispersed well over the edge and external surface of the clay layers. [Copyright &y& Elsevier]

Copper was adsorbed onto Ca-exchanged montmorillonite (Cheto clay) under basic conditions. Differential thermogravimetric analysis (DTGA) combined with evolved gas mass spectroscopy (MS) was employed as the principal technology to study the distribution and structure of adsorbed copper species on the montmorillonite clay. The results showed that the original clay was easily rehydrated. After copper adsorption, a step-by-step replacement of hydrated calcium ions by copper–ammonia complex was observed through the gradual decrease of the first DTGA dehydration peak intensity with increasing copper loading. Compared with the original clay, copper loaded samples showed new DTGA peaks assigned to NH3 and N2O. The presence of the N2O peak suggested that the loaded copper species were in agglomerated copper oxide form, which dispersed well over the edges and external surfaces of the clay layers. [Copyright &y& Elsevier]

• The design sensitivity analysis of transient responses is considered. • The adjoint variable method (AVM) is derived in a state-space formulation. • The discretize-then-differentiate AVM is adopted for non-viscously damped systems. • The time-history analysis relies on a modified precise integration method. • Computational considerations of proposed method are investigated and compared. In this paper, a new design sensitivity analysis (DSA) method for transient responses of non-viscously damped systems is developed. The damping force of the non-viscously damped systems depends on the past history of motion and is represented by convolution integrals over suitable kernel functions. The equations of motion are first transformed into a state-space formulation and the time-history analysis of the responses relies on a modified precise integration method (MPIM). The residual equation in each discrete time step is achieved by a recurrence formula of the MPIM. The sensitivities of the transient responses are calculated with an adjoint variable method (AVM). In particular, a discretize-then-differentiate approach is adopted for the DSA. The accuracy, consistency, implementation effort and computational complexity are discussed. Two numerical examples are illustrated to show the performances of the proposed method compared with other two methods. The results indicate that, when calculating the sensitivities of the transient responses for non-viscously damped systems based on the MPIM, the order of differentiation and discretization has no obvious effect on the consistency. The proposed state-space based discretize-then-differentiate AVM is more efficient than other two methods. [ABSTRACT FROM AUTHOR]

• LaCl 3 poisoning can decrease the expressions of PI3K, p-AKT, p-mTOR, HIF-1α, and VEGF in the hippocampus of offspring rats. • LaCl 3 poisoning can induce developmental injuries and cell apoptosis in hippocampal neurons of offspring rats. • LaCl 3 poisoning can decrease the learning and memory abilities of offspring rats. This study examined the effects of the AKT/mTOR/HIF-1α signaling pathway on learning and memory in offspring rats induced by lanthanum from neuroethology and molecular biology perspectives. 32 pregnant adult Wistar rats were divided into four groups randomly: control group (NC), 0.25%, 0.5% and 1.0% LaCl 3 groups (n = 8). All rats were poisoned through free drinking from day 0 of pregnancy to postnatal day 21 (suckling period). All offspring rats were poisoned through free drinking from delactation to postnatal day 48. Offspring rats aged 49-days-old were used as sampling objects to construct an LaCl 3 poisoning model of offspring rats. Changes in hippocampal neurons, apoptosis of hippocampal neurons, learning and memory abilities of LaCl 3 -poisoned animals were measured by Nissl staining, TUNEL method and the shuttle box test, respectively. Expressions of PI3K, AKT, and mTOR, HIF-1α, and VEGF in the hippocampus were tested by qPCR and Western blot. Distributions of PI3K and p-AKT in hippocampal neurons were observed through the immunohistochemical method. With increasing LaCl 3 dose, lightning strike time and active avoidance incubation period of offspring rats in the different LaCl 3 groups were significantly prolonged. The Nissl body positive neurons of hippocampal neurons gradually declined while apoptosis in cells increased. The expressions of both mRNA (PI3K, AKT, mTOR, HIF-1α, VEGF) and proteins (PI3K, p-AKT, p-mTOR, HIF-1α, VEGF) in the hippocampus of the LaCl 3 groups were significantly lower than those of NC group (p < 0.05). LaCl 3 poisoning can induce developmental injuries in hippocampal neurons and can increase cell apoptosis. As a result, learning and memory abilities of offspring rats, as well as the expressions of PI3K/AKT/mTOR, are decreased, thus inhibiting activation of HIF-1α and influencing the expression of the downstream VEGF gene. [ABSTRACT FROM AUTHOR]

Microplastics, which are tiny plastic particles less than 5 mm in diameter, are widely present in the environment, have become a serious threat to aquatic life and human health, potentially causing ecosystem disorders and health problems. The present study aimed to investigate the effects of microplastics, specifically microplastics-polystyrene (MPs-PS), on the structural integrity, gene expression related to tight junctions, and gut microbiota in mice. A total of 24 Kunming mice aged 30 days were randomly assigned into four groups: control male (CM), control female (CF), PS-exposed male (PSM), and PS-exposed female (PSF)(n = 6). There were significant differences in villus height, width, intestinal surface area, and villus height to crypt depth ratio (V/C) between the PS group and the control group(C) (p <0.05). Gene expression analysis demonstrated the downregulation of Claudin-1, Claudin-2, Claudin-15, and Occludin, in both duodenum and jejunum of the PS group (p < 0.05). Analysis of microbial species using 16S rRNA sequencing indicated decreased diversity in the PSF group, as well as reduced diversity in the PSM group at various taxonomic levels. Beta diversity analysis showed a significant difference in gut microbiota distribution between the PS-exposed and C groups (R2 = 0.113, p<0.01), with this difference being more pronounced among females exposed to MPs-PS. KEGG analysis revealed enrichment of differential microbiota mainly involved in seven signaling pathways, such as nucleotide metabolism(p<0.05). The relative abundance ratio of transcriptional pathways was significantly increased for the PSF group (p<0.01), while excretory system pathways were for PSM group(p<0.05). Overall findings suggest that MPs-PS exhibit a notable sex-dependent impact on mouse gut microbiota, with a stronger effect observed among females; reduced expression of tight junction genes may be associated with dysbiosis, particularly elevated levels of Prevotellaceae. [ABSTRACT FROM AUTHOR]