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This work presents results on the finiteness, and on the symmetry properties, of various homological dimensions associated to the Jacobson radical and its higher syzygies, of a semiperfect ring. [ABSTRACT FROM AUTHOR]

The academic community has spent a lot of time and effort in recent years discussing the fact that gamification has a significant positive impact on encouraging user engagement behaviour. As the mainstream of current research, gamification affordance refers to the action possibilities provided by the gamified elements and features of gamified systems. However, there is a lack of research on how to improve users’ knowledge sharing behaviour by introducing gamification affordances into the social question and answer (Q&A) community. This study develops a causal relationship model between gamification affordance and knowledge sharing behaviour by utilising the social Q&A community as the research object. The fundamental characteristics of gamification affordance which users value are defined through a semi-structured interview based on a focus group. The results of the structural equation model analysis on Chinese users (n = 310) demonstrate that gamification affordances enhance the gamified experience of users, thus improving user satisfaction, and ultimately affecting users’ knowledge sharing behaviour. Furthermore, this study explored the important role of gamification affordance in the development of the social Q&A community and verified the significant role of gamified experience in enhancing the psychological outcomes of users. The study concludes with a discussion-worthy theoretical and practical significance. [ABSTRACT FROM AUTHOR]

Summary: Numerous guidelines have called for personalized interventions to address childhood obesity. The role of fat mass and obesity‐associated gene (FTO) in the risk of childhood obesity has been summarized. However, it remains unclear whether FTO could influence individual responses to obesity interventions, especially in children. To address this, we systematically reviewed 12,255 records across 10 databases/registers and included 13 lifestyle‐based obesity interventions (3980 children with overweight/obesity) reporting changes in body mass index (BMI) Z‐score, BMI, waist circumference, waist‐to‐hip ratio, and body fat percentage after interventions. These obesity‐related outcomes were first compared between children carrying different FTO genotypes (rs9939609 or its proxy) and then synthesized by random‐effect meta‐analysis models. The results from single‐group interventions showed no evidence of associations between FTO risk allele and changes in obesity‐related outcomes after interventions (e.g., BMI Z‐score: −0.01; 95% CI: −0.04, 0.01). The results from controlled trials showed that associations between the FTO risk allele and changes in obesity‐related outcomes did not differ by intervention/control group. To conclude, the FTO risk allele might play a minor role in the response to obesity interventions among children. Future studies might pay more attention to the accumulation effect of multiple genes in the intervention process among children. [ABSTRACT FROM AUTHOR]

A numerical modeling method to reproduce the structures of needle-punched nonwoven geotextile based on the actual manufacturing process (web formation and web bonding) was developed. The geotextile model was built based on the statistical characteristics of the computed tomography (CT) observations, physical and mechanical properties of fibers, and physical parameters of the geotextile. A combination of the finite element model and pore network model method was proposed to obtain the pore size characteristics. The appearance and pore size characteristics before and under uniaxial tensile strains were investigated. It is shown that the method can simulate the geotextile manufacturing process satisfactorily. The pore size distribution (PSD) curves obtained from the model show good agreement with the CT-based results. Moreover, the method can reasonably simulate the tensile behaviors of geotextile under uniaxial tensile strain. The specimen necking phenomenon during the uniaxial tensile test was well reproduced. The PSD curves moved towards the direction of larger pore size with increasing uniaxial strain, and characteristic pore sizes (O 98 , O 95 , O 50 , O 30 , O 10) all show a relatively steady increasing trend. • The structures of nonwoven geotextiles are reproduced by numerical simulation of the actual preparing process (web formation and web bonding). • A FEM-PNM method was proposed to obtain the pore size characteristics of the geotextile model. • The PSD curves obtained from the numerical model show a good agreement with the experimental results based on CT. • The specimen necking phenomenon during the uniaxial tensile test was well reproduced. • The PSD curves moved towards the direction of larger pore size with uniaxial strain, and characteristic pore sizes all show an increasing trend. [ABSTRACT FROM AUTHOR]

Background: Differentiated thyroid cancer (DTC) is increasingly common in women of reproductive age. However, whether pregnancy increases the risk of DTC progression/recurrence after treatment remains controversial. The study aimed to assess the association of pregnancy with risk of progression in patients previously treated for DTC. Methods: This was a retrospective cohort study following 123 pregnant women and 1376 nonpregnant women at Peking University Third Hospital after initial treatment for DTC between January 2012 and December 2022. To control the effect of confounding, we carefully matched pregnancy (n = 107) and nonpregnancy groups (n = 298) in terms of baseline characteristics by using propensity score matching (PSM). Results: At baseline, the pregnancy and nonpregnancy groups were balanced in all matched variables. At follow-up, the percentage of DTC progression in the two groups was 12 (11.8%) and 47 (15.8%), respectively. Regression models showed no evidence of association of pregnancy with the risk of progression (odds ratio: 0.74 and 95% confidence interval: 0.37–1.50; p = 0.404), and remained consistent across long/short follow-up and other subgroup variables. We found that the shorter the time interval between treatment and pregnancy, the higher the risk of DTC progression (ptrend = 0.019). Conclusions: The risk of DTC progression in pregnant women was not higher than that in the well-matched, nonpregnant women. For young women previously treated for DTC, disease progression might not be a concern for their future pregnancy plan, but it seems safer to wait at least 1 year before pregnancy compared with immediate pregnancy. [ABSTRACT FROM AUTHOR]

The poor wet-oxidation resistance limits the long-life service of SiC f /SiC composites as the hot end components of aero-engines. The stability of SiC f /SiC composites under high-temperature wet oxygen environment can be promoted by more robust SiC matrix. In this work, the effect of Y 2 O 3 on the corrosion behaviors of SiC ceramics in flowing O 2 /H 2 O atmosphere at 1400 ℃ was studied. Duo to the continuous Y 2 Si 2 O 7 layer formed on the surface, SiC-Y 2 O 3 ceramics exhibit much better wet-oxidation resistance than original SiC ceramics. During the oxidation process, Y 2 O 3 dispersed in the ceramics migrates to the surface and reacts with SiO 2 to form β-Y 2 Si 2 O 7. Subsequently, the β-Y 2 Si 2 O 7 aggregates and grows to form a continuous Y 2 Si 2 O 7 layer, inhibiting the corrosion from oxidizing medium to the inner SiC matrix. This study is expected to provide important ideas for the design and structure regulation of wet-oxidation resistant SiC f /SiC composites. [ABSTRACT FROM AUTHOR]

Well-defined polycarbonate diol was successfully synthesized through a strategy using a combination of organocatalyst and water. Such strategy was less developed in organocatalyzed polymerization and frequently regarded as side reactions. Herein, one-component phosphonium borane Lewis pairs PB1–PB8 were successfully applied in the copolymerization of CO2 and cyclohexene oxide (CHO) to generate poly(CHO-alt-CO2) carbonate (PCHC). Parameters of linker length and counter anion effects on the catalyst activity were investigated. It was found that Lewis pair PB3 served as a dual initiator and catalyst in the copolymerization of CHO and CO2 with or without the presence of water. In contrast, Lewis pair PB8 can serve as a true catalyst for the preparation of well-defined α,ω)-hydroxyl PCHC diols. This was achieved by introducing a labile CF3COO group as counter anion through anion exchange reaction while water molecules acted as chain transfer agents. The function of trifluoroacetate group in the polymerization process was investigated in detail and possible mechanism was proposed. Upon changing the amount of water and catalyst loading, PCHC diols with varied molecular weight (1.5 kg/mol to 7.5 kg/mol), low dispersities (Ð<1.2) and carbonate content (>99%) could be easily obtained. The low molecular weight PCHC diol was used as a bifunctional macroinitiator for the ring-opening polymerization of L-lactide (LLA) to afford ABA triblock copolymer in one-pot synthesis. [ABSTRACT FROM AUTHOR]

Excessive exudate secreted from diabetic wounds often results in skin overhydration, severe infections, and secondary damage upon dressing changes. However, conventional wound dressings are difficult to synchronously realize the non‐maceration of wound sites and rapid exudate transport due to their random porous structure. Herein, a self‐pumping Janus hydrogel with aligned channels (JHA) composed of hydrophilic poly (ethylene glycol) diacrylate (PEGDA) hydrogel layer and hydrophobic polyurethane (PU)/graphene oxide (GO)/polytetrafluoroethylene (PTFE) layer is designed to rapidly export exudate and accelerate diabetic wound healing. In the design, the ice‐templating process endows the hydrophilic hydrogel layer with superior liquid transport ability and mechanical strength due to the formation of aligned channel structure. The hydrophobic layer with controlled thickness functions as an effective barrier to prevent exudate from wetting the skin surface. Experiments in diabetic rat model show that JHA can significantly promote re‐epithelialization and collagen deposition, shorten the inflammation phase, and accelerate wound healing. This unique JHA dressing may have great potential for real‐life usage in clinical patients. [ABSTRACT FROM AUTHOR]

Two digital image methods based on scanning electron microscope (SEM) and computed tomography (CT) were proposed to study the microstructural characteristics of staple fibers and continuous filament geotextiles. Two-dimensional (2D) image analysis was developed for SEM images using a machine-learning-based segmentation algorithm. Three-dimensional (3D) image analysis of the CT images was based on 3D reconstruction and a pore network model. The fiber orientation distribution, porosity, pore size distribution (PSD), and characteristic pore size O 95 determined from image analysis were compared with the theoretical equation and bubble point test (BBP) results. It is shown that 2D and 3D image analyses can accurately measure the fiber orientation distribution of the geotextiles. The porosity values obtained using 3D imaging were comparable to theoretical values. The PSD curves obtained in the BBP tests were in good agreement with those obtained using the 3D image method. O 95 sizes of continuous filament geotextiles estimated by 2D image analysis compared well with O 95 sizes obtained by BBP tests, whereas this was not the case for staple fiber geotextiles. The O 95 pore throat sizes of the two nonwoven geotextiles determined by 3D image analysis were comparable to the BBP test-based values and 2D image analysis-based values. • The applicability and results of 2D and 3D image methods for measuring the microstructure characteristics of nonwoven geotextiles were discussed. • A machine learning-based 2D image method without complex sample preparation and parameter tuning was proposed. • 2D image analysis have accurate results of O 95 sizes for continuous filament nonwoven geotextiles. • 3D image analysis is a good approach for determining the pore characteristic of nonwoven geotextiles. [ABSTRACT FROM AUTHOR]

BACKGROUND: Recent studies have reported the association between air pollution exposure and reduced kidney function. However, it is unclear whether air pollution is associated with an increased risk of acute kidney injury (AKI). OBJECTIVES: To address this gap in knowledge, we investigated the effect estimates of long-term exposures to fine particulate matter [PM ≤ 2.5 μm in aerodynamic diameter (PM2.5)], nitrogen dioxide (NO2), and ozone (O3) on the risk of first hospital admission for AKI using nationwide Medicare data. METHODS: This nationwide population-based longitudinal cohort study included 61,300,754 beneficiaries enrolled in Medicare Part A fee-for-service (FFS) who were ≥65 years of age and resided in the continental United States from the years 2000 through 2016. We applied Cox-equivalent Poisson models to estimate the association between air pollution and first hospital admission for AKI. RESULTS: Exposure to PM2.5, NO2, and O3 was associated with increased risk for first hospital admission for AKI, with hazard ratios (HRs) of 1.17 (95% CI: 1.16, 1.19) for a 5-μg/m³ increase in PM2.5, 1.12 (95% CI: 1.11, 1.13) for a 10-ppb increase in NO2, and 1.03 (95% CI: 1.02, 1.04) for a 10-ppb increase in summer-period O3 (June to September). The associations persisted at annual exposures lower than the current National Ambient Air Quality Standard. DISCUSSION: This study found an association between exposures to air pollution and the risk of the first hospital admission with AKI, and this association persisted even at low concentrations of air pollution. Our findings provide beneficial implications for public health policies and air pollution guidelines to alleviate health care expenditures and the disease burden attributable to AKI. [ABSTRACT FROM AUTHOR]

Knowledge about the spatial-temporal pattern of cropland abandonment is the premise for the management of abandoned croplands. Traditional mapping approaches of abandoned croplands usually utilize a multi-date classification-based land cover change trajectory. It requires quality training samples for land cover classification at each epoch, which is challenging in regions of smallholder agriculture in the absence of high-resolution imagery. Facing these challenges, a theoretical model is proposed to recognize abandoned croplands based on post-abandonment secondary succession. It applies the continuous change detection and classification (CCDC) temporal segmentation algorithm to Landsat time series (1986~2021) to obtain disjoint segments, representing croplands' status. The post-abandonment secondary succession showing a greening trend is recognized using NDVI-based harmonic analysis, so as to capture its preceding abandonment. This algorithm is applied to a mountainous area in southwest China, where cropland abandonments are widespread. Validation based on stratified random samples referenced by a vegetation index time series and satellite images shows that the detected abandoned croplands have user accuracy, producer accuracy and an F1 score ranging from 43% to 71%, with variation among abandonment year. The study area has a potential cropland extent of 22,294 km2, within which 9252 km2 of the cropland was abandoned. The three peak years of abandonment were 1994, 2000, and 2011. The algorithm is suitable to be applied to large-scale mapping due to its automatic manner. [ABSTRACT FROM AUTHOR]

Accurate land cover mapping is challenging in Southeast Asia where cloud coverage is prevalent and landscape is heterogenous. Object-based mapping, multi-temporal images and combined use of optical and microwave data, provide abundant features in spectral, spatial, temporal, geometric and polarimetric dimensions. And random forest is usually employed due to robustness and efficiency in handling high-dimensional and noisy data. This study assesses whether feature selection and ensemble analysis, which are rarely adopted, yield improved result. Recursive feature elimination decreases original 568 features into a subset of 53 features, achieving the optimal combination of features. Ensemble analysis of random forest, support vector machine, and K-nearest neighbors leads to an overall accuracy of 0.816. Comparison experiments demonstrated the merits of the multi-temporal, multi-source approach, feature elimination and ensemble analysis. [ABSTRACT FROM AUTHOR]

We prove that any faithful Frobenius functor between abelian categories preserves the Gorenstein projective dimension of objects. Consequently, it preserves and reflects Gorenstein projective objects. We give conditions on when a Frobenius functor preserves the stable categories of Gorenstein projective objects, the singularity categories and the Gorenstein defect categories, respectively. In the appendix, we give a direct proof of the following known result: for an abelian category with enough projectives and injectives, its global Gorenstein projective dimension coincides with its global Gorenstein injective dimension. [ABSTRACT FROM AUTHOR]

Urban waterbodies are one of the most pertinent issues involved in multiple aspects of Sustainable Development Goals (SDGs). However, waterbodies in large Chinese cities are highly vulnerable to urban-land expansion, which is mostly due to economic development, population growth, and rural–urban migration. In this work, we selected 159 Chinese cities of over one million in population to investigate the encroachment on waterbodies due to rapid urbanization from 1990 to 2018. Overall, 20.6% of natural waterbody area was lost during this period to urban expansion, and this fraction varied from city to city which was related to waterbody abundance. With the acceleration of urbanization, waterbody occupation is becoming more serious (P < 0.01). However, in all cities, this encroachment has eased since 2010, which justifies the effective implementation of national-scale policies to conserve urban waterbodies. Meanwhile, gains have occurred during urbanization, in addition to the loss of waterbodies. Especially, cities lacking waterbody placed a greater emphasis on ecological factors, whose urban waterbody areas showed an increasing trend. In the future, ecological resources, including waterbody, should be considered in urban planning to provide reasonable protection to waterbodies in the quest for urban sustainability. [ABSTRACT FROM AUTHOR]

Microwave pretreatment could be an invaluable method to improve the efficiency of the rock breakage in the excavation and comminution operations. To investigate the influence of microwave irradiation on the thermal response and mechanical behavior of compact rocks, a series of physical and mechanical experiments were conducted on the nontreated and treated basalts. The mineral compositions of the basalts were obtained by X-ray diffraction (XRD) test. Scanning electron microscope (SEM) images and geological sketch were utilized to analyze the propagation pattern of the microcracks and macrofractures caused by the microwave irradiation. High power density microwave can induce the complication of the microcracks and exchange the pattern of the macrofracture network. Based on the uniaxial compression strength (UCS) test, the mechanical performance of the basalts was evidently reduced with the increase of the microwave power and exposure time. The experimental results prove that microwave-assisted method has significant potential application to preweakening rocks in civil and mining engineering. [ABSTRACT FROM AUTHOR]

This research introduces the recentering energy dissipation bracing with a pendulum in prefabricated steel frame (REBP-PSF) structures. The primary objective of this study is to mitigate potential severe damage to steel frames during seismic events and to expedite postearthquake rehabilitation. This innovative system harnesses energy dissipation through friction between structural members and facilitates recentering through the cable pretensioning force. Consequently, this may make postearthquake repairs minimal or even unnecessary. Three REBP-PSF structures and a prefabricated steel frame with cantilever beam splices (PSF-CBS) were meticulously modeled using the ABAQUS finite element method to evaluate the seismic performance of this novel system. The study investigated the effects of pretensioning parameters and varied structural morphologies on seismic performance metrics, including failure modes, hysteresis performance, energy dissipation capacity, and residual displacements. This paper introduced a simplified method to simulate the restoring force model of REBP using the connection element method. Subsequently, a model for the REBP-RSF overall structure was established, enabling nonlinear dynamic time-history analysis, which was then compared with the rigid steel frame (RSF) structure. The results showed that the REBP-PSF structure outperformed the PSF-CBS in terms of initial stiffness, yield load, ultimate load, and energy dissipation capability. The bearing and energy dissipation capacities of the REBP-PSF structure were enhanced by augmenting the cable pretensioning force within this structure. The proposed connection element method could accurately simulate the hysteretic behavior of REBP. Compared with the RSF structure, the REBP-RSF demonstrated superior seismic performance, characterized by small story drift and residual displacements during seismic activities. Furthermore, a notable augmentation was observed in the lateral stiffness and torsional rigidity of the proposed structure. • The REBP-PSF structure is proposed and its seismic performance is analyzed. • The REBP-PSF structure dissipates energy through friction between REBP. • The connection element method is proposed and verified. • The REBP-RSF structure based on the connection element method is established. [ABSTRACT FROM AUTHOR]

This paper proposes a phase generated carrier (PGC) demodulation scheme for sinusoidal phase modulation interferometer (SPMI) that does not require a second harmonic carrier signal. In this scheme, an in-phase interference signal component with direct current (DC) bias is obtained by low-pass filtering the original interference signal, and a quadrature interference signal component is obtained by conventional means. The Lissajous figure formed by these two quadrature interference signal components is an ellipse whose center deviates from the origin of the I-Q coordinates. By fitting this ellipse, the major and minor axes and the center coordinates can be obtained. These elliptic parameters are then used to eliminate DC bias and normalize the amplitude of the quadrature signal components. Finally, the phase demodulation of the interference signal can be realized by using arctangent algorithm or differential cross multiplication (DCM) algorithm. The results of simulation and experiment have verified the validity and accuracy of the proposed PGC demodulation scheme, and show that it is insensitive to the phase modulation depth C. Compared with conventional PGC demodulation, this scheme requires lower depth of carrier phase modulation. The vibration measurement results indicate that the average signal-to-noise and distortion Ratio (SINAD) and total harmonic distortion (THD) values of demodulation results in the frequency range of 130 Hz to 250 Hz are 34 dB and -33 dB respectively. The proposed PGC demodulation scheme shows good performance in displacement measurement using SPMI. • A novel PGC demodulation scheme without using a second harmonic carrier signal. • Lissajous ellipse with center deviated from origin in I-Q coordinates. • Demodulation performance comparison, test for the signal-to-noise and distortion ratio and the total harmonic distortion. • PGC demodulation scheme with a low optimal phase modulation depth. [ABSTRACT FROM AUTHOR]

Brain functional network (BFN) has become an increasingly important tool to discover informative biomarkers for diagnosing neurodegenerative diseases, such as Alzheimer's disease and its prodrome stage, namely mild cognitive impairment. Currently, the most popular BFN estimation methods include Pearson's correlation and sparse representation. Despite their empirical success in some scenarios, such estimated BFNs only capture the low-order relationship (i.e., the direct connectivity strength between brain regions), ignoring the high-order information in the brain (e.g., the global network structure). Therefore, in this study, we proposed a novel method based on the signed random walk (SRW) to estimate high-order BFNs. Not only can SRW measure the global network structure, but it can also naturally deal with negative brain functional connectivity through the structural balance theory. To the best of our knowledge, this study was the first to use SRW in BFN estimation. Furthermore, considering the complex interaction among different brain regions, we developed a parameterized variant of SRW for improving the flexibility of the high-order BFN estimation model. To illustrate the effectiveness of the proposed method, we identified patients with mild cognitive impairment from normal controls based on the estimated high-order BFNs. Our experimental findings showed that the proposed scheme tended to achieve higher classification performance than baseline methods. [ABSTRACT FROM AUTHOR]

Spatiotemporal fusion is a topical framework for solving the mutual restricted problem between the spatial and temporal resolution of satellite images. We pioneer an approach to replace similarity measurement steps in spatiotemporal fusion algorithms with convolutional neural networks (CNNs), building a bridge between weight function-based models and the learning-based models. Specifically, we propose a nonlocal form that separates the relational computation part from the value representation part, and construct the CNN-based similarity weight learning block for learning normalized weights. The block can be inserted into spatial and temporal adaptive reflectance fusion model (STARFM) to replace the manually designed weight calculation rules common in weight function-based methods, or into the CNN model StfNet to better utilize neighboring high-resolution images. The trained model outputs a high-resolution prediction from each base date image pair. The final result is a combination of the two predictions. In this regard, we propose the standard deviation-based weights to combine two prediction results. Four experiments are performed on Landsat–Moderate-resolution Imaging Spectroradiometer (MODIS) image pairs to determine the following: 1) the performance of the model at the target training date; 2) the generalization of the model in the target training time period; and 3) the generalization of the model at different dates and different geographical locations, each considering the different cases of giving one and two pairs of known images. Experimental results demonstrate the superiority of the similarity weight learning block and standard deviation-based weights. Among them, STARFM with the similarity weight learning block exhibits strong generalization, which testifies to the practical value of our model. [ABSTRACT FROM AUTHOR]

For any finite dimensional algebra Λ given by a quiver with relations, we prove that its dg singularity category is quasi-equivalent to the perfect dg derived category of a dg Leavitt path algebra. The result might be viewed as a deformed version of the known description of the dg singularity category of a radical-square-zero algebra in terms of a Leavitt path algebra with trivial differential. The above result is achieved in two steps. We first introduce the singular Yoneda dg category of Λ, which is quasi-equivalent to the dg singularity category of Λ. The construction of this new dg category follows from a general operation for dg categories, namely an explicit dg localization inverting a natural transformation from the identity functor to a dg endofunctor. This localization turns out to be quasi-equivalent to a dg quotient category. Secondly, we prove that the endomorphism algebra of the quotient of Λ modulo its Jacobson radical in the singular Yoneda dg category is isomorphic to the dg Leavitt path algebra. The appendix is devoted to an alternative proof of the result using Koszul-Moore duality and derived localizations. [ABSTRACT FROM AUTHOR]

Clean energy has become an important component of the transition to a sustainable future, of which offshore wind power is a promising clean energy source. However, there are still gaps in the spatiotemporal data of OWTs with global coverage, precise location, freely available, and with long time series of installation time information. This study proposes a cost-effective method to investigate the global distribution and installation time of offshore wind turbines (OWTs) using remote sensing data and the GEE cloud computing platform. The process includes two parts, the first is OWTs extraction through synthetic SAR images using an adaptive Z-score threshold and morphological operations. The second part is installation time detection through synthetic Landsat optical images using LandTrendr algorithm. A total of 12,412 OWTs have been identified within the offshore Exclusive Economic Zones (EEZ) of countries worldwide, with 5915 in Europe, 6490 in Asia, and only 7 in the United States. Most OWTs are situated in nearshore areas and were constructed in a regular pattern. Installation dates of existing OWTs worldwide reveal an exponential growth trend since the 21st century, with Europe leading the way and Asia catching up rapidly, building two-thirds of its turbines after 2019. This information can be used for subsequent studies on the effectiveness of wind energy in reducing greenhouse gas emissions, the potential for future development and expansion of wind energy infrastructure, as well as to inform policies aimed at promoting the sustainability of the wind energy industry. • We identify 12412 offshore wind turbines worldwide in 2022. • Most turbines are nearshore with a regular pattern. • Exponential growth in installation since the 21st century. • Europe is leading in construction, while Asia is rapidly catching up. • The data guides future energy infrastructure development and sustainable policies. [ABSTRACT FROM AUTHOR]

Meristems in land plants share conserved functions but develop highly variable structures. Meristems in seed-free plants, including ferns, usually contain one or a few pyramid-/wedgeshaped apical cells (ACs) as initials, which are lacking in seed plants. It remained unclear how ACs promote cell proliferation in fern gametophytes and whether any persistent AC exists to sustain fern gametophyte development continuously. Here, we uncovered previously undefined ACs maintained even at late developmental stages in fern gametophytes. Through quantitative live-imaging, we determined division patterns and growth dynamics thatmaintain the persistent AC in Sphenomeris chinensis, a representative fern. The AC and its immediate progenies form a conserved cell packet, driving cell proliferation and prothallus expansion. At the apical centre of gametophytes, the AC and its adjacent progenies display small dimensions resulting from active cell division instead of reduced cell expansion. These findings provide insight into diversified meristem development in land plants. [ABSTRACT FROM AUTHOR]

In order to determine the effect of different oligosaccharides on growth performance, intestinal health, and antioxidant status of broilers, 240 1-day-old XiangHuang broilers were randomly distributed to 4 treatments with 6 replicates each. Birds were fed corn-soybean-based diets (CON), and birds in xylo-oligosaccharides (XOS), fructo-oligosaccharides (FOS), and iso-maltooligosaccharide (IMO) groups were given the basal diet supplemented with 200 mg/kg XOS, FOS, and IMO, respectively. Result showed that average daily gain (ADG) during the whole 5 weeks in FOS group was greater than that in control group (p < 0.05). Both breast and thigh muscle percentages were higher for birds fed XOS versus CON (p < 0.05). Oligosaccharides supplementation increased jejunal villus height compared with control group (p < 0.05). Malondialdehyde (MDA) concentration in breast muscle was lower for birds fed diet containing FOS versus CON (p < 0.05). Activities of total superoxide dismutase (T-SOD) in serum and thigh muscle were higher in IMO than in control group (p < 0.05). Serum T-SOD and breast muscle's glutathione peroxidase (GSH-Px) activity was higher in XOS compared with control group (p < 0.05). Conclusion, dietary oligosaccharides such as XOS, FOS, and IMO could improve intestinal health and antioxidant ability of muscle without affect growth performance in broilers. [ABSTRACT FROM AUTHOR]

In this paper, we mainly study a diffusive Leslie–Gower prey–predator model by the geometric singular perturbation theory. Under assumptions that the diffusion rate of prey is much smaller than that of predator and the natural growth rate of prey is much greater than that of predator, we use dimensionless transformation and traveling wave transformation to transform the diffusive Leslie–Gower prey–predator model into a Multi-scale slow-fast system with two small parameters of different magnitude. According to the Tikhonov–Finichel singular perturbation theory, we analyse the Multi-scale dynamics with respect to two small parameters in turn. Furthermore, we prove the existence of heteroclinic orbit for the slow-fast system. Thus, we get the existence of travelling waves of original reaction-diffusion model. Finally, numerical examples are given to support our theoretical results. [ABSTRACT FROM AUTHOR]

For a finite dimensional algebra A, the bounded homotopy category of projective A-modules and the bounded derived category of A-modules are dual to each other via certain categories of locally-finite cohomological functors. We prove that the duality gives rise to a 2-categorical duality between certain strict 2-categories involving bounded homotopy categories and bounded derived categories, respectively. We apply the 2-categorical duality to the study of triangle autoequivalence groups. [ABSTRACT FROM AUTHOR]

0.93Bi0.5Na0.5TiO3-0.07BaTiO3 ceramics doped with 0.01?mol Er3+ have been prepared and their photoluminescence (PL), ferroelectric, dielectric, and piezoelectric properties have been studied. By doping Er3+ at various sites, ceramics containing oxygen or cation vacancies have been prepared and their effects have been investigated. Ceramic containing no vacancy (i.e., doping Er3+ at the Bi3+ site) has also been prepared as a reference for the study. In addition to the reduction of the up-conversion PL emissions at 532, 547, and 660?nm, our results also reveal that oxygen vacancies can enhance, at the expense of the visible emissions, the near-infrared (1.44-1.66?μm) and mid-infrared (2.62-2.84?μm) down-conversion emissions. Similar results have also been observed for the ceramics containing cation vacancies, and the enhancement in the near-infrared emission becomes much more significant, reaching about 70% for the ceramic doped with Er3+ at the Na+ site. These should be attributed to the looping mechanism between the 4F7/2, 2H11/2, 4I9/2, and 4I11/2 levels facilitated by the cation vacancies and the efficient cross relaxations. The ceramics also exhibit reasonably good ferroelectric, dielectric, and piezoelectric properties, suggesting that they have great potential for multifunctional applications. [ABSTRACT FROM AUTHOR]

Considering L be a completely distributive lattice, the notion of the sum of L-convex spaces is introduced and its elementary properties is studied. Firstly, the connections between the sum of L-convex spaces and its factor spaces are established. Secondly, the additivity of separability (S-1, sub-S0, S0, S1, S2, S3 and S4) are investigated. Finally, the additivity of five types special L-convex spaces are examined. [ABSTRACT FROM AUTHOR]

Incorporating three-dimensional (3D) spatial measurement into the urban expansion measurement system plays an important role in understanding the degree of urban expansion and regulating and governing it. This article proposes an urban concrete forest and constructs an Urban Volume Sprawl Index to quantitatively study the spatiotemporal characteristics of the three-dimensional expansion of Chinese prefecture-level cities. Furthermore, geographic detectors are used to study its influencing factors. The following conclusions are drawn: (1) Between 1990 and 2018, the volume of Chinese cities has increased from 414.67 to 1,406.29 km3, with a growth rate of 239.13%. (2) The overall growth rate of urban volume shows a gradual slowing trend during the research period, from 55.99% to 40.83%. (3) Between 1990 and 2018, the Urban Volume Sprawl Index nationwide gradually slowed down (from 5.18% to 3.90%), with the largest rate reported in the western region (4.1%), the middle in the eastern region (3.46%), and the smallest in the central region (3.28%). (4) Government and economic factors have the greatest impact on the three-dimensional expansion of Chinese cities (over 69%), with social factors in the middle, and natural factors having the weakest explanatory power (less than 15%). (5) There are differences in the degree of urban expansion between two-dimensional and three-dimensional perspectives. A total of 38.1% of cities have a greater degree of urban expansion from a two-dimensional (2D) analysis perspective, which are mainly small cities located in the western and eastern regions. A total of 5.4% of cities (mainly located in the Yangtze River Delta and Pearl River Delta regions) have a greater degree of urban expansion from a 3D perspective. The remaining cities (56.5%) go through the same level of urban expansion in both analysis dimensions. A 3D urban expansion analysis can better explain and reveal the actual production and living space provided by urban expansion than 2D analysis. It can provide temporal data for urban land efficiency evaluation, ghost city identification, etc., and it has good application and promotion prospects. [ABSTRACT FROM AUTHOR]

Frequent spontaneous combustion activities restrict ecological restoration of coal waste dumps after reclamation. Effective monitoring of vegetation restoration is important for ensuring land reclamation success and preserving the ecological environment in mining areas. Development of unmanned aerial vehicle (UAV) technology has enabled fine-scale vegetation monitoring. In this study, we focused on Medicago sativa L. (alfalfa), a representative herbaceous vegetation type, in a coal waste dump after reclamation in Shanxi province, China. The alfalfa aboveground biomass (AGB) was used as an indicator for assessing vegetation restoration. The objective of this study was to evaluate the capacity of UAV-based fusion of RGB, multispectral, and thermal infrared information for estimating alfalfa AGB using various regression models, including random forest regression (RFR), gradient boosting decision tree (GBDT), K-nearest neighbor (KNN), support vector regression (SVR), and stacking models. The main results are as follows: (i) UAV multi-source data fusion improved alfalfa AGB estimation accuracy, although the enhancement diminished with the increasing number of sensor types. (ii) The stacking model consistently outperformed RFR, GBDT, KNN, and SVR regression models across all feature fusion combinations. It achieved high accuracy with R2 of 0.86–0.88, RMSE of 80.06–86.87 g/m2, and MAE of 60.24–62.69 g/m2. Notably, the stacking model based on only RGB imagery features mitigated the accuracy loss from limited types of features, potentially reducing equipment costs. This study demonstrated the potential of UAV in improving vegetation restoration management of coal waste dumps after reclamation. [ABSTRACT FROM AUTHOR]

Accurate and up-to-date built-up area mapping is of great importance to the science community, decision-makers, and society. Therefore, satellite-based, built-up area (BUA) extraction at medium resolution with supervised classification has been widely carried out. However, the spectral confusion between BUA and bare land (BL) is the primary hindering factor for accurate BUA mapping over large regions. Here we propose a new methodology for the efficient BUA extraction using multi-sensor data under Google Earth Engine cloud computing platform. The proposed method mainly employs intra-annual satellite imagery for water and vegetation masks, and a random-forest machine learning classifier combined with auxiliary data to discriminate between BUA and BL. First, a vegetation mask and water mask are generated using NDVI (normalized differenced vegetation index) max in vegetation growth periods and the annual water-occurrence frequency. Second, to accurately extract BUA from unmasked pixels, consisting of BUA and BL, random-forest-based classification is conducted using multi-sensor features, including temperature, night-time light, backscattering, topography, optical spectra, and NDVI time-series metrics. This approach is applied in Zhejiang Province, China, and an overall accuracy of 92.5% is obtained, which is 3.4% higher than classification with spectral data only. For large-scale BUA mapping, it is feasible to enhance the performance of BUA mapping with multi-temporal and multi-sensor data, which takes full advantage of datasets available in Google Earth Engine. [ABSTRACT FROM AUTHOR]

We give two proofs of the following theorem and a partial generalization: if a finite‐dimensional algebra A is derived equivalent to a smooth projective scheme, then any derived equivalence between A and another algebra B is standard, that is, isomorphic to the derived tensor functor by a two‐sided tilting complex. The main ingredients of the proofs are as follows: (1) between the derived categories of two module categories, liftable functors coincide with standard functors; (2) any derived equivalence between a module category and an abelian category is uniquely factorized as the composition of a pseudo‐identity and a liftable derived equivalence; (3) the derived category of coherent sheaves on a certain class of projective schemes is triangle‐objective, that is, any triangle autoequivalence on it, which preserves the isomorphism classes of all objects, is necessarily isomorphic to the identity functor. [ABSTRACT FROM AUTHOR]

The basic pore unit model is extended to predict the strained pore size characteristics of woven slit-film geotextiles subjected to unequal biaxial tensile strains. The strained per cent open area (POA) and analytical pore size are expressed as functions of the weft strain and the warp strain to weft strain ratio. The influence of the biaxial tensile strain on pore size characteristics is evaluated in three woven slit-film polypropylene geotextile samples using image analysis under the warp strain to weft strain ratios of 1, 2, 3 and 4. It is shown that the experimental POA and O 95 increased significantly with increasing strain at different warp strain to weft strain ratios, and the PSD curves moved toward the direction of large open sizes. The analytical models of POA and pore size can accurately predict the increasing trend of POA and O 95. Moreover, unequal biaxial tensile strains can significantly change the shape of the pores, which may influence the results of the pore size obtained by indirect methods. A larger warp strain to weft strain ratio can lead to a larger change in the pore shape when the length to width ratios of initial pores are close to 1. [ABSTRACT FROM AUTHOR]

To each symmetrizable Cartan matrix, we associate a finite free EI category. We prove that the corresponding category algebra is isomorphic to the algebra defined in Geiss et al. (2017) [4] , which is associated to another symmetrizable Cartan matrix. In certain cases, the algebra isomorphism provides an algebraic enrichment of the well-known correspondence between symmetrizable Cartan matrices and graphs with automorphisms. [ABSTRACT FROM AUTHOR]

Let $R$ be a two-sided Noetherian ring, and let $M$ be a nilpotent $R$ -bimodule, which is finitely generated on both sides. We study Gorenstein homological properties of the tensor ring $T_{R}(M)$. Under certain conditions, the ring $R$ is Gorenstein if and only if so is $T_{R}(M)$. We characterize Gorenstein projective $T_{R}(M)$ -modules in terms of $R$ -modules. [ABSTRACT FROM AUTHOR]

We have developed a method to quantify the sweetness of negatively charged high-potency sweeteners coexisting with other taste substances. This kind of sweetness sensor uses lipid polymer membranes as the taste-sensing part. Two types of outputs have been defined in the measurement of the taste sensor: one is the relative value and the other is the CPA (the change in membrane potential caused by adsorption) value. The CPA value shows a good selectivity for high-potency sweeteners. On the other hand, the relative value is several times higher than the CPA value, but the relative value is influenced by salty substances. In order to obtain both high sensitivity and selectivity, we established a model for predicting the concentration of sweeteners with a nonlinear regression analysis method using the relative values of both the sweetness sensor and the saltiness sensor. The analysis results showed good correlations with the estimated concentration of acesulfame potassium coexisting with salty substances, as represented by R² = 0.99. This model can correspond well to the prediction of acesulfame K in a concentration of 0.2–0.7 mM, which is commonly used in food and beverages. The results obtained in this paper suggest that this method is useful for the evaluation of acesulfame K using the taste sensors. [ABSTRACT FROM AUTHOR]

This study aims to determine the important selection attributes of instant noodles that significantly affect consumer satisfaction in Korea and China. Several factors such as taste, price, quality, design, and brand were tested, and the relationships between satisfaction and repurchase intention were analyzed. Based on previous studies, it was found that the importance of selection attributes for instant noodle is taste, price, quality, design, and brand. Using structural equation modeling, 1,027 questionnaires were surveyed for a statistical method of examining the proposed hypotheses in China and Korea. Results of the study reveal that the importance of selection attributes affected satisfaction significantly. Furthermore, the path coefficient of satisfaction that leads to repurchase was found to be significant. However, consumers' perceived importance of selection attributes of instant noodles varied according to the countries. The path coefficients from taste to satisfaction were more significant for Korean consumers (β = 0.542) than for Chinese consumers (β = 0.359). Meanwhile, the path coefficient from corporate brand to satisfaction was more significant for Chinese consumers (β = 0. 305) than Korean consumers (β = 0.218). This study analyzes the significant selection attributes of instant noodles, the results provide meaningful implications for instant noodle companies in each country regarding the specific attributes they need to prioritize. [ABSTRACT FROM AUTHOR]

China is a major coal producing country, and also one of the countries which has the most serious coal mine accidents around the world. As a result of geological conditions, underground mining is the main way that coal is exploited in China; serious underground disasters and the corresponding fatality rate are much higher than is the case for surface mining. Although safer modern underground mining methods have been introduced across China, accidents still lead to fatalities and the loss of revenue in some mines. It is important to establish a georeferenced coal mine disasters (CMD) database to aid researchers and decision makers in better understanding the spatio-temporal distribution of such accidents across in China. This study has proposed a method to develop a georeferenced spatio-temporal CMD database via a geographic information system (GIS) platform based on statistical data released by the State Administration of Coal Mine Safety (SACMS) for the period between 2000 and 2015. The different levels and spatio-temporal characteristics of coal mining accidents were analyzed, and the space-time scan statistic permutation (STSSP) model was carried out to detect the CMD clusters; and finally, a spatio-temporal cluster analysis of Chinese coal mining accidents in 2000 and 2015 was conducted. [ABSTRACT FROM AUTHOR]

In this paper, some low-level separation axioms of L-convex spaces are introduced, including S-1, sub-S0, S0, S1 and S2 separation axioms. Some relevant properties of these separation axioms are discussed. In particular, the relationships between convex spaces and induced L-convex spaces on some separation axioms are investigated. [ABSTRACT FROM AUTHOR]

For certain full additive subcategories X of an additive category A , one defines the lower extension groups in relative homological algebra. We show that these groups are isomorphic to the suspended Hom groups in the Verdier quotient category of the bounded homotopy category of A by that of X. Alternatively, these groups are isomorphic to the negative cohomology groups of the Hom complexes in the dg quotient category A / X , where both A and X are viewed as dg categories concentrated in degree zero. [ABSTRACT FROM AUTHOR]

A simultaneous optimization approach for heat exchanger network (HEN) synthesis and detailed shell-and-tube heat exchanger (HE) design including phase changes is proposed based on a genetic/simulated annealing algorithm (GA/SA). Firstly, a model for HEN synthesis considering utility HEs with phase change is established by combining the improved stage-wise superstructure model of HEN synthesis with non-isothermal mixing of splits and detailed design models of HEs involving phase change, the minimum total annual cost accounting for pumping cost is set as the key objective. Secondly, two alternative connection schemes for HEs, which are referred to as one-stream series-wound and one-stream parallel in the stage-wise superstructure of the HEN, were applied. Thirdly, a simultaneous optimization strategy is proposed. Required areas of HEs obtained by stage-wise superstructure, overall heat-transfer coefficients and pressure drops based on the dimension parameters of HEs are used to connect HEN synthesis and the detailed design of each HE. Finally, a flowchart of optimization procedures using GA/SA was presented to solve the problem, and an inner iterative loop of the area of HE is used to guarantee the feasibility of the solution. Two examples results are used to illustrate the availability of the proposed model and algorithm. • A model for HEN synthesis considering utility HEs with phase change is proposed. • A flowchart of simultaneous optimization procedure is proposed based on GA/SA. • An inner iteration loop is proposed to ensure the feasibility of the solutions. • GA/SA is used to synchronize the evolution of HEN and HE geometry parameters. • The optimal results of example 2 decrease TAC by 22.1%. [ABSTRACT FROM AUTHOR]

• Multi-source data are integrated to effectively construct RSEI in successive years. • The characteristics of ecological quality variation have been revealed. • The weak positive trend delayed by mining has been proved. • The extent and area of the better or worse trend have been identified. Coal-based industries are critical to the contemporary world's growth, while the environmental degradation associated with the industry is also increasing. In this study, we develop the Remote Sensing Ecological Index (RSEI) and map its distribution from 2000 to 2020 using the Muli coalfield near Qinghai Lake as the research object. This index is obtained by fitting four components that are critically related to the quality of the ecological environment, including greenness, humidity, heat and dryness, to finally obtain a desirable evaluation. The results illustrate that: (1) The RSEI displayed an overall increasing trend on the time scale, but it also went through three lengthier phases of trend changes. In space view, the RSEI of the unaltered areas has greatly improved, while the damaged areas are clearly concentrated in the study area's northwestern region, where mining is common. (2) In the trend test, the overall variation of RSEI was found to be around 3%. RSEI significantly increased in 69.57% of the study region, whereas RSEI decreased dramatically in 30.43% of the study area. (3) In opencast mining disturbed areas and undisturbed areas, a different quality structure can be discovered, with Moderate and Good levels predominating in disturbed areas and Good and Excellent levels predominating in undisturbed areas. The ecological decline in damaged areas significantly hampered the overall upward trend of RSEI. (4) The Globalmoran's I value was 0.558, 0.546, 0.409, 0.574, and 0.680 in 2000, 2005, 2010, 2015, and 2020, respectively, showing a positive association between regional distribution of ecological environment quality and that opencast mining does really degrade that quality. It has been demonstrated that our evaluation accurately classify the local environment as affected by opencast mining, making it crucial for studying the relationship between coal mining and ecological quality. This index can also be utilized in the future when conducting surveys of other regions of intense human disturbance. [ABSTRACT FROM AUTHOR]

Epithelioid inflammatory myofibroblastic sarcoma (EIMS) is an aggressive subtype of inflammatory myofibroblastic tumour which rarely affects the chest cavity. We, for the first time, report a case of mediastinal EIMS with the EML4-ALK fusion. A young woman presented to our hospital with cough, chest tightness and shortness of breath. Computed tomography (CT) showed a mixed attenuation soft-tissue mass in the right middle and upper mediastinum. Negative results were obtained from bronchoscopy forceps biopsy and endobronchial ultrasound-guided transbronchial fine needle aspiration. CT-guided percutaneous biopsy was finally performed. However, due to the rapidly progressed EIMS that compressed the trachea and right main bronchus, the patient died of respiratory failure 1 day before diagnosis. EIMS progresses rapidly, and an early diagnosis is important. For mediastinal EIMS, CT-guided percutaneous biopsy may be useful. Next-generation sequencing of blood may be instructive to EIMS patients who are intolerant to invasive biopsy. [ABSTRACT FROM AUTHOR]

As a biodegradable polyester, the commercialized synthesis protocol of poly(ε-caprolactone) (PCL) under mild conditions is of great significance and attractive. Herein, the ring-opening polymerization (ROP) of ε-caprolactone (ε-CL) using FeCl3 catalyst and benzyl alcohol (BnOH) as the initiator was developed. FeCl3 has been proved to be an efficient catalyst for the ROP of ε-CL under mild conditions. The conversion of ε-CL to PCL was 98.8% at 60 °C within 4 h, with number-average molecular weight (Mn) and dispersity (PDI) of 1.65 × 104 g/mol and 1.28, respectively. Moreover, a coordination-insertion ring-opening polymerization mechanism mediated by FeCl3 was proposed. Overall, this work is expected to provide a feasible industrial method for the preparation of PCL from the direct aerobic oxidation of cyclohexanone. [ABSTRACT FROM AUTHOR]

Coal mining has contributed to a solid and stable global economy. Surface mining and underground mining are the principal methods for extraction of coal worldwide and given the developments in mining technology and equipment, these methods are increasingly generating more and more coal. Surface mining is also a subject that cannot be overlooked in the context of sustainable development because amongst human activities it causes comparatively strong land disturbance. Much of the damage and assessment of land and ecosystems from surface mining occurs at the site, and at the regional scale; hence access to the mining data is limited. Moreover, it is difficult for remote sensing to extract information on larger-scale areas with high precision. As a consequence, a frequency index of open coal mining can be created by merging the vast high-resolution images acquired by Landsat sensors with the spectral properties of open coal scraped from the overburden layer. Such indices and morphological principles can be used to develop strategies for quickly identifying the open coal boundaries in a vast area without mine-related information. In addition, LandTrendr may be used to reconstruct the spatial and temporal processes of surface disturbance and remediation caused by regional surface coal mining to identify surface mining disturbance and reclamation. Seven typical mining locations worldwide were selected to test and confirm the proposed method's practicality and robustness, including delivering accurate findings based on randomly testing sample points and comparing the mature data outputs. The results showed that: (1) the overall accuracy of the open coal areas identified by the OCFI (Open Coal Frequency Index) was over 85 % (range 0.85–0.96). In all study areas, the accuracy of recognizing disturbance and reclamation events was greater than 76 %. (2) The surface mining disturbed 3046.42 km2 of land and 1487.39 km2 was reclaimed in the seven mining areas investigated between 1986 and 2018, resulting in a reclamation rate of 48.82 %. The proposed method is more accurate and faster in identifying open coal locations than the current commonly used land cover datasets based on comparisons with other data products. The approach can extract surface coal mining in the absence of mining data and offer precise boundary data for mining research, which can be extremely useful for extending mining operations. [ABSTRACT FROM AUTHOR]

Abstract We prove that any derived equivalence between derived-discrete algebras of finite global dimension is standard, that is, isomorphic to the derived tensor functor by a two-sided tilting complex. [ABSTRACT FROM AUTHOR]