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The joint transmit and receive beamforming algorithm has been envisioned to optimise the target's signal‐to‐interference‐plus‐noise ratio by co‐designing the transmit and receive beamforming vectors simultaneously. However, the traditional design concepts for this algorithm only consider the monostatic radar system, which may not work as well for the multistatic radar system. The authors present a novel transmit and receive beamforming algorithm for the multistatic radar system that includes a common transmitter and multiple receivers. The transmit beamforming vector can directly influence the output signal‐to‐interference‐plus‐noise ratio of each radar subsystem. To ensure the balanced performance of the subsystems, the authors propose a weighted sum of the signal‐to‐interference‐plus‐noise ratio optimisation problem to co‐design the transmit and receive beamforming. The proposed problem is non‐convex, and the authors construct an iterative algorithm to solve it using semi‐definite relaxation and slack‐variable replacement techniques. By using pre‐determined weights, the output performance of each radar subsystem can be effectively regulated. The simulation results confirm that the proposed algorithm can ensure better output signal‐to‐interference‐plus‐noise ratio for the entire multistatic radar system than the conventional joint transmit and receive beamforming algorithm. [ABSTRACT FROM AUTHOR]

For a fixed bounded Lipschitz domain and a family of systems of linear elasticity with rapidly oscillating periodic coefficients, we investigate a necessary and sufficient condition that an A 1 weight ω must satisfy in order for the weighted W 1 , 2 (ω) estimates for weak solutions of Neumann problems to be true. Moreover, in any Lipschitz domain, under the assumption that the coefficient A is Hölder continuous, we prove that the uniform W 1 , p estimates for solutions to the Neumann problem hold for 2 d d + 1 − δ < p < 2 d d − 1 + δ. As a by-product, in non-periodic setting with A ∈ V M O , we are able to show that the W 1 , p estimates hold for 2 d d + 1 − δ < p < 2 d d − 1 + δ. The ranges are sharp for d = 2 , 3. Finally, we prove an extrapolation result for L p Dirichlet problems for systems of linear elasticity. Specifically, we extrapolate from solvability for 1 < p 0 < 2 (d − 1) d − 2 to the range p 0 < p < 2 (d − 1) d − 2 + δ. The novelty is that the method avoids using the L 2 regularity estimate. [ABSTRACT FROM AUTHOR]

The conventional joint transmit and receive beamforming algorithms maximise the output signal‐to‐interference‐plus‐noise ratio (SINR) by designing the weight coefficients simultaneously at the transmitter and receiver. However, their performance degrades significantly when the model mismatch exists. In this paper, the robust version of the joint transmit and receive beamforming method is considered in the context of the bistatic radar system. In particular, both the transmit array and the receive array suffer model mismatch. The designed beamformer aims to maximise its output SINR subjected to a robustness constraint by simultaneously designing the transmit beamforming vector and the receive beamforming vector. Two types of robustness constraints, namely the worst‐case constraint and the probability constraint, are considered in this paper. The proposed formulations are non‐convex, and the sub‐optimal solutions are obtained by a sequential optimization approach. In addition, a novel method to estimate the interference‐plus‐noise covariance matrices at the transmitter and receiver is proposed, which makes the proposed robust joint beamforming algorithms adapt to the variation of the surrounding environment. Numerical simulations verify the effectiveness of the proposed algorithms. [ABSTRACT FROM AUTHOR]

In statistical mechanics, the formation free energy of an i-mer can be understood as the Gibbs free energy change in a system consisting of pure monomers after and prior to the formation of the i-mer. For molecules interacting via Lennard-Jones potential, we have computed the formation free energy of a Stillinger i-mer [F. H. Stillinger, J. Chem. Phys. 38, 1486 (1963)] and a ten Wolde–Frenkel (tWF) [P. R. ten Wolde and D. Frenkel, J. Chem. Phys. 109, 9901 (1998)] i-mer at spinodal at reduced temperatures from 0.7 to 1.2. It turns out that the size of a critical Stillinger i-mer remains finite and its formation free energy is on the order of kBT, and the size of a critical tWF i-mer remains finite and its formation free energy is even higher. This can be explained by Binder's theory [K. Binder, Phys. Rev. A 29, 341 (1984)] that for a system, when approaching spinodal, if the Ginzburg criterion is not satisfied, a gradual transition will take place from nucleation to spinodal decomposition, where the free-energy barrier height is on the order of kBT. [ABSTRACT FROM AUTHOR]

For a family of second-order parabolic systems with rapidly oscillating and time-dependent periodic coefficients, we investigate the asymptotic behavior of Green function. The asymptotic behavior, as ε → 0 , of G ε (x , t ; y , s) and ∇ x G ε (x , t ; y , s) as well as ∇ x ∇ y G ε (x , t ; y , s) are obtained. These results will be used to investigate the boundary layer phenomena and higher-order convergence in periodic homogenization. To the author's best knowledge, our results are new even for the time-independent case. [ABSTRACT FROM AUTHOR]

The detection of antibiotics is still the focus of global attention, because their abuse can lead to biological hazards. Herein, three new coordination polymers as fluorescent sensors, namely [Cd3(L1)(MTC)2(H2O)6] (CP 1), [Zn(L1)(HMTC)·2H2O] (CP 2) and [Cd3(L2)(MTC)2(H2O)6] (CP 3) [H3MTC = trimellitic acid, L1 = (E)-4,4′-(ethene-l,2-diyl)bis(N-pyridin-3-yl)benzamide) and L2 = (E)-4,4′-(diazene-1,2-diyl)bis(N-(pyridin-3-yl)benzamide)], were synthesized by using two bis(pyridyl)-bis(amide) ligands with different spacers and trimellitic acid mixed ligands under hydrothermal conditions, which were structurally characterized by single crystal X-ray diffraction, PXRD and IR. CP 1 and CP 3 have similar 2D coordination networks and 3D supramolecular structures, while CP 2 is a 2D coordination structure formed by alternatively linking 1D chains of Zn-L1 and Zn-HMTC, which is further extended to a 3D supramolecular framework. In addition, CPs 1–3 can highly efficiently detect two classes of antibiotics, chlortetracycline and furaltadone, with low LODs, excellent anti-interference ability, pH stability and recyclability. In CPs 1–3, CP 1 has the lowest LOD (5.12 × 10−8 M for CTC and 9.41 × 10−8 M for FTD). The sensing mechanisms, and the influences of composition and structure differences on the performances are discussed. The results provide a reasonable experimental reference for designing CPs and understanding the influencing factors of fluorescence performances. [ABSTRACT FROM AUTHOR]

The Helmholtz free energy of a constrained supersaturated vapor with a cluster size distribution consisting of clusters of various sizes is modeled as a mixture of hard spheres of various sizes attracting each other. This model naturally takes into account monomer-monomer and monomer-cluster interactions, so it implicitly pertains to nonideal gases, unlike prior work. Based on this model, the expressions for the equilibrium concentration and the formation free energies of clusters in a metastable supersaturated vapor have been derived. These results indicate that the widely used formula, ni = n1exp(−βΔGi), that computes the formation free energy of a cluster does not work at high supersaturations. As an example, the formation free energies of clusters with Stillinger's physical cluster definition in metastable, highly supersaturated vapors interacting via Lennard-Jones potential are studied using these expressions. Noticeable differences have been found for both the formation free energies of clusters and sizes of the critical clusters computed from our proposed expressions vs those from the formula ni = n1exp(−βΔGi). [ABSTRACT FROM AUTHOR]

Hefei's gross domestic product (GDP) growth rate ranks first among all cities in China, and it was the fastest-growing city in China from 2000 to 2020. The high-speed economic development inevitably led to rapid changes in land cover types, e.g., an increment in artificial features (built-up) and decrement in natural features (vegetation). However, (1) many previous studies focus on the land cover change in metropolis or at the global scale, yet few focus on underdeveloped but fast-growing cities; (2) land cover studies mainly focus on global variations, yet seldom on local characteristics. Thus, it is of great significance to monitor the land cover change for the city with the fastest economic growth in China based on the long time-series satellite images from both global and local perspectives. In this study, with support from huge amounts of data (including 719 Landsat TM/ETM+/OLI satellite images, land surface temperature, nighttime satellite images, DEM, multiple land cover products, and various auxiliary data), processing and parallel computing abilities of the GEE platform, classification maps of land cover in Hefei from 2000 to 2020 are produced based on a random forest machine learning method, and the spatio-temporal variations and driving factors are analyzed from both global and local viewpoints. The results show that: (1) the classification accuracy is excellent; the average overall accuracy is 93% and the Kappa coefficient is 0.88; (2) the general spatio-temporal variations in land cover in Hefei from 2000 to 2020 are obvious; the built-up area expanded from 419.72 km2 to 1530.20 km2, with a total growth rate of 264.58%. With the expansion of the built-up area, the vegetation coverage decreased by 16.61% (1652.56 km2); (3) the land surface temperature shows an increment trend in the new town yet a decrement trend in the old town due to the change in vegetation coverage and the decentration of administration centers; further analysis shows that the population and the social economy are two driving factors for land cover changes. It is worth noting that both the area and coverage of vegetation in the old town and water body area in Hefei increased significantly, although the fast urbanization inevitably caused a decrement in vegetation and water area in the whole city, indicating both the high-speed economic development and improvement in green surfaces simultaneously experienced in Hefei from 2000 to 2020. [ABSTRACT FROM AUTHOR]

Luminescence sensing of biomarker 3-nitrotyrosine (3-NT) with coordination polymers (CPs) is of great significance and rarely investigated, especially in improving the sensing performance by regulating the particle of CPs. Herein, we synthesized a new 3D LCP, [Cd3(L)(BTC)2(H2O)2]·2H2O (LCP 1) (H3BTC = 1,3,5-benzenetricarboxylic acid, L = (E)-4,4′-(ethene-1,2-diyl)bis[(N-pyridin-3-yl)benzamide]), which demonstrates a rare example of direct detecting 3-NT by LCPs as fluorescent sensors. Meanwhile, nanoscale LCP 1 (Nano-LCP 1) with a smaller size was prepared by adjusting the reaction conditions. Nano-LCP 1 not only shows the same high selectivity, anti-interference ability and fast response time as LCP 1, but also has a higher quantum yield (31.80%, about 3 times that of Bulk-LCP 1) and a lower detection limit (2.30 × 10−8 M, about 20 times that of Bulk-LCP 1). A detailed detection mechanism of LCP 1 towards 3-NT and the effect of the size difference on the luminescence sensing performance were discussed, providing a valuable reference for the rational design, mechanism interpretation, and performance improvement of LCP-based fluorescence sensors. [ABSTRACT FROM AUTHOR]

3-Nitrotyrosine (3-NT), an oxidative stress biomarker, is closely associated with various diseases. Thus, rapid and sensitive detection of 3-NT is of great significance for preventing and treating diseases. Herein, we reported a new 3D zinc-based metal–organic framework (Zn-MOF) [Zn(L)(HBTC)] (L = (E)-4,4′-(ethene-1,2-diyl)bis[(N-pyridin-3-yl)benzamide], H3BTC = 1,3,5-benzenetricarboxylic acid), which was structurally characterized by single crystal X-ray diffraction, IR, PXRD and TG. The Zn-MOF can be used as a highly efficient fluorescence sensing material to provide a direct and low-cost method for the rapid detection of 3-NT and shows high sensitivity with a KSV value of 6.596 × 104 M−1, a rapid luminescence response within 24 s, excellent selectivity, high anti-interference ability and good recyclability. It is the first example of a MOF being used to directly detect 3-NT as a luminescence sensor to our knowledge. The sensing mechanism of the Zn-MOF towards 3-NT is discussed in detail, which provides a basis for the rational design of MOF sensing materials and their application in biomarker detection. [ABSTRACT FROM AUTHOR]

• Bacterial diversity in the mainstream diminished compared to tributaries. • Dispersal limitation governs bacterial communities in river network at regional scale. • Variations in distance metrics influenced the distance decay relationship within river. • Headwaters and high-altitude tributary confluences affect the bacterial community. Microorganisms in rivers indeed play a crucial role in nutrient cycling within aquatic ecosystems. Understanding the assembly mechanisms of bacterial communities in river networks is essential for predicting their special composition and functional characteristics in natural rivers. This study employed 16S rRNA gene amplicon sequence variation (ASVs) to scrutinize the bacterial community within the uniquely topographical Ili River network. The bacterial community composition varied across the three tributaries with distinct sources and the mainstream. The confluence of various sources diminished the diversity of the bacterial community and altered the functionality of within mainstream. We suggest that strong dispersal limitation predominantly shaped the community at the regional scale (46.6 %), underscoring the significant contribution of headwater sites to bacterial community composition. Contrary to expectation, the bacterial resources in the mainstream were not enriched by the higher diversity in three tributaries. Instead, confluence disturbance potentially increased the undominated processes (36.7 %) and alter the bacterial community composition at the local scale of the mainstream. The intricate coalescence at the confluence could potentially be an intriguing causative factor. Our research indicates that the composition of bacterial communities within intricate river networks exhibits biogeographic patterns, simultaneously influenced by river confluence and geographical features, necessitating multi-scale analysis. [Display omitted] [ABSTRACT FROM AUTHOR]

• First presented a universal canopy gap fraction (GF) model for forests with various tree distributions. • Accuracy of canopy GF at off-nadir is significantly improved by the new model. • Universality and accuracy of the universal model are validated by a ray-tracing method. • Universal model form the backbone of the development of a potentially universal canopy reflectance model. An accurate estimation of forest canopy gap fraction (GF) is a prerequisite for remote sensing retrievals of several associated canopy parameters e.g. leaf area index, fAPAR (fraction of photosynthetically active radiation absorbed by the canopy), clumping index, etc. A universal canopy GF model for forests is required for various tree distribution patterns on flat and slopping terrains, yet existing models so far do not possess all these abilities simultaneously. For example, the Neyman type-A model, the Poisson model, and the hypergeometric model are suitable only to forests with clumped, random, and regular tree distributions, respectively. In this regard, the suite of Nilson's canopy GF models developed for forests with various tree distributions have the potential to become universal models. For this purpose, this study attempts to overcome the following limitations of these models to make them be true universally applicable: (1) canopy GF calculated by the Nilson's models is mostly accurate for various tree distributions at nadir; whereas at it is either underestimated for clumped tree distributions or overestimated for regular tree distributions at off-nadir; and (2) Nilson's models were developed for flat terrains and untested for sloping terrains. Herein, two Nilson's models are modified by expanding the calculation of overlaps among crowns (OAC) at nadir to the whole hemispherical space. The results show that all canopy GF simulations in the new models (New91 and New99) show higher consistency with ray-tracing results than those in original Nilson's models in all directions, highlighting the need to consider directional OAC. The modified models (especially for New99) are validated in two RAMI forest stands and a Saihanba forest stand: the relative error in canopy GF between the modified models and a ray-tracing model is less than 10 % in all forest stands. The modified models (especially New99) are suitable for various tree distributions on flat and slopping terrains and therefore increased the universality of the original Nilson's models suitable for a wide-range of remote sensing applications. New99 can be deemed as a universal canopy GF model for forests with various tree distributions. [ABSTRACT FROM AUTHOR]

Background and Aims. Regional anaesthesia reports to attenuate stress and inflammatory responses associated with surgical resection; however, the effectiveness of combined nerve blocks is less often investigated. We evaluated whether a combination of a pectoral nerve block (PNB) and stellate ganglion block (SGB) is more effective than a PNB alone in reducing these responses in women undergoing modified radical mastectomy (MRM). Methods. This is a prospective randomized controlled trial. Fifty patients with breast cancer were randomly allocated to receive an ultrasound-guided PNB (n = 25 , PNB only group) or ultrasound-guided PNB combined with SGB (n = 25 , combined blockade group). The primary outcome was perioperative plasma level of interleukin- (IL-) 6. Secondary outcomes included perioperative plasma levels of cortisol, glucose, IL-8, and tumour necrosis factor- (TNF-) α, pain scores, haemodynamic variables, sleep quality, and complications postsurgery. Results. The combined blockade group exhibited significantly lower IL-6 and TNF-α levels 24 h postsurgery. Cortisol levels were significantly lower in the combined blockade group at the end of the surgery. Glucose levels at the time of incision were lower in the combined blockade group. Pain scores up to 12 h postsurgery were significantly lower in the combined blockade group, which also exhibited better perioperative haemodynamic stability. Patients in the combined blockade group reported better sleep quality on the night of surgery. Conclusion. In patients undergoing MRM, PNB combined with SGB block effectively blunted perioperative inflammatory response than PNB alone. A combined block approach can also alleviate stress response and postoperative acute pain with stable perioperative haemodynamics and better postoperative sleep quality. [ABSTRACT FROM AUTHOR]

With the popularization and development of Internet of Things technology, a large number of music and dance videos have emerged in all walks of life. In this information age, video communication has become a widespread communication method. In the current music and dance collection process, most of the action frame information of the dance video is repeated, and the stage background and costumes of the dance action are too many to fully express the human body movement information. Based on these problems, this article will realize the application of the intelligent sensor-based action recognition technology in the field of dance movement collection and complete the collection and recognition of music and dance movements. The research results of the article show that: (1) in the dance video image extraction process, the feature recognition effect of the proposed algorithm is the highest among the three models. The recognition effect of the upper body is 66.1, and the recognition effect of the lower body is 61.0. The image recognition effect can reach 73.4. During the statistical experiments on the recognition of different regions of the human body, the recognition effect of the intelligent sensor model proposed in the article is still the highest among the three models. The recognition effect of the upper body is 33.9, and the recognition effect of the lower body is 33.9. The recognition effect is 34.5, and the recognition effect of the whole body is 40.7. (2) In the traditional music and dance collection mode, the P values of the four test parts are all greater than 0.05, indicating that in the traditional music and dance collection mode, the differences between the four test modules are not significant. Combined with the evaluation results of the three groups in the traditional music and dance collection mode, we can conclude that under the condition that the initial conditions are basically the same, and the training conditions and environment are basically the same, the trainees who use the smart sensor music and dance collection training method are better in physical fitness. The indicators have been better improved, and the effect is greatly optimized compared with the training effect in the traditional music and dance collection mode. (3) After the test set runs, the article proposes that the accuracy rate of the dance collection model based on the smart sensor algorithm is 88.24%, the accuracy rate can reach 88.96%, the improved accuracy rate can reach 91.46%, and the accuracy rate can reach 91.79%. The ROC curve value of the article and the improved model is very stable. The ROC value before the improvement remains at about 0.90, and the ROC value after the model improvement also remains at 0.96. After the test set runs, the performance of the four models has decreased to a certain extent, but the smart sensor dance acquisition model proposed in the article has the lowest degree of decline, and the performance after the decline is still the highest among the four models. The accuracy of the model is 90.24%, and the accuracy of the improved model is 93.16%. The ROC curve values of the improved system are very stable, the ROC value has been maintained at 0.95, and the ROC value before the improvement is stable within the range of 0.85–0.95. The experimental results further illustrate that the model proposed in the article has the best performance. [ABSTRACT FROM AUTHOR]

In this paper, we investigate several classes of binary operations within the preordered framework. First, we give the definition of quasi-t-subnorm on preordered sets. Subsequently, we research two classes of quasi-t-subnorms by means of Adjunctions and Left Galois Connections respectively. Meanwhile, we introduce new preorders differing from the inclusion order on powersets. Importantly, quasi-t-subnorms can be defined on powersets with preorders. Then we get a class of extensive binary operations via Adjunctions between preordered sets and the preordered sets consisting of powersets, which generalizes the previous results. The relationship between related binary operations is explored at last. [ABSTRACT FROM AUTHOR]

Comparison and validation of canopy reflectance (CR) models are two important steps to ensure their reliability. Pure forest plantations are an ideal type of forest for validating CR models because of their simple background and the low variance in the crown structures which are usually assumed to be identical in most CR models. A Geometric Optical Model for Forest Plantations (GOFP) was compared using dataset in two radiation transfer model intercomparison exercise (RAMI) stands and validated using in situ dataset of detailed optical and structural data of two forest plantations in the Saihanba Forestry Center, China. The results show that (1) the tree distributions in stands described by the hypergeometric model in GOFP show good consistencies with the dataset in the two RAMI stands and measurements from the two Saihanba forest stands; and (2) the CRs simulated with GOFP are also compared well in the two RAMI stands and validated with measurements collected with unmanned aerial vehicles in the two Saihanba stands. GOFP shows a better consistency with the CR measurements than those from CR models for natual forestsbecause the tree distribution in forest plantations is described more reasonably in GOFP. [ABSTRACT FROM AUTHOR]

We present here the synthesis of a novel fluorescent actinide polyrotaxane compound URCP1 through the utilization of an end‐cutting pseudorotaxane precursor with only the cucurbit[6]uril (CB[6]) macrocyclic components acting as linking struts. The non‐coordinating guest motif in the obtained polyrotaxane, with increased freedom and structural flexibility, can display intriguing temperature‐triggered conformational variations inside the cavity of CB[6], which was clearly evidenced by crystallographic snapshots at different temperatures. Notably, this observation of temperature‐triggered structural dynamics in URCP1 represents the first report of actinide polyrotaxane with such feature in solid‐state. Moreover, URCP1 has a high photoluminescence quantum yield (PLQY) of 49.8 %, comparable to other luminescent uranyl compounds, and can work as a fluorescent probe to selectively detect Fe3+ over other eight competing cations in aqueous solution, with the limit of detection being as low as 4.4×10−3 ppm. [ABSTRACT FROM AUTHOR]

We propose a new approach for performing drained and undrained loading of elastoplastic geomaterials over large deformations using smoothed particle hydrodynamics (SPH), a meshfree continuum particle method, combined with the modified Cam Clay (MCC) model of critical state soil mechanics. The numerical approach draws upon a novel one‐particle two‐phase penalty‐method based formulation for handling undrained loading in saturated soils, which allows tracking of the buildup of pore‐water pressures under combined shearing and compression. Large‐scale parallelized simulations are employed to accommodate a significant number of degrees of freedom in a three‐dimensional setting. After verification and benchmark testing, the SPH based formulation is used to analyze the propagation of reverse faults through fluid‐saturated clay deposits and the rupture of strike‐slip faults across earthen embankments. The computational methodology tests the robustness of the meshfree approach in situations where the soil tends to dilate on the ‘dry’ side of the critical state line and to compact on the ‘wet’ side, but cannot, because of the incompressibility constraint imposed by undrained loading. Our results extend the current understanding of fault rupture modeling and further demonstrate the potential of our framework together with the SPH method for large deformation analyses of complex problems in geotechnics. [ABSTRACT FROM AUTHOR]

The pointing accuracy of a radio telescope is usually less than one-tenth of its antenna beam width. For large-aperture antennas at the short-centimeter band or millimeter-wave band, the pointing accuracy must be as high as several arc seconds. Therefore, for large-diameter and high-frequency reflector antennas, the pointing problem has become an important focal point to realize the antenna performance. Among many structural subsystem factors that affect the antenna pointing accuracy, there has been only less study on the factor of main reflector deformation. Based on the structural characteristics of the antenna, a reflector space coordinate system is established in this paper. And based on the space coordinates of the main reflector surface points after deformation, a non-linear least squares fitting method with 3 degrees of freedom is proposed to accurately predict the antenna pointing. Finally, the space geometric relationship is used to strictly derive the precise adjustments on the elevation and azimuth in order for correcting the antenna pointing error, and the indirect relationship between the main reflector deformation and the pointing error is constructed. This has certain guiding significance for improving the pointing accuracy of large radio antennas. [ABSTRACT FROM AUTHOR]

For a family of second-order parabolic systems in divergence form with rapidly oscillating periodic and time-dependent coefficients. We establish the pointwise estimates of the Green's matrices. We investigate uniform boundary Lipschitz estimates and boundary Hölder estimates as well as non-tangential maximum function estimates in C 1 , η or C 1 cylinders. Consequently, we also obtain the Agmon-Miranda maximum principle. [ABSTRACT FROM AUTHOR]

This paper is concerned with quantitative homogenization of second-order parabolic systems with periodic coefficients varying rapidly in space and time, in non-self-similar scales. The homogenization problem involves two oscillating scales. We obtain large-scale interior and boundary Lipschitz estimates as well as interior C 1 , α and C 2 , α estimates by utilizing higher-order correctors. We also investigate the problem of convergence rates for initial-boundary value problems. [ABSTRACT FROM AUTHOR]

Extensive restricted canonical ensemble Monte Carlo simulations [D. S. Corti and P. Debenedetti, Chem. Eng. Sci. 49, 2717 (1994)] were performed. Pressure, excess chemical potential, and excess free energy with respect to ideal gas data were obtained at different densities of the supersaturated Lennard-Jones (LJ) vapor at reduced temperatures from 0.7 to 1.0. Among different constraints imposed on the system studied, the one with the local minimum of the excess free energy was taken to be the approximated equilibrium state of the metastable LJ vapor. Also, a comparison of our results with molecular dynamic simulations [A. Linhart et al., J. Chem. Phys. 122, 144506 (2005)] was made. [ABSTRACT FROM AUTHOR]

In this paper, we focus on the construction of non-direct product triangular norms on product lattices. First, we give one class of non-direct product triangular norms on more general product lattices, which generalizes the previous results. Subsequently, we provide another class of non-direct product triangular norms on product lattices, which differ from others. Our work gives an alternative answer to an open problem proposed by Jenei and De Baets. [ABSTRACT FROM AUTHOR]

Two new CdII/ZnII coordination polymers using the bis(pyridyl)-bis(amide) ligand as the main ligand and 1,2,4,5-benzenetetracarboxylic acid (H 4 BTEC) as the auxiliary ligand were designed and synthesized, which can sensitively detect biomarker 3-nitrotyrosine as fluorescence sensors. They have the advantages of excellent stability, anti-interference, recyclability and low limits of detection. [Display omitted] 3-Nitrotyrosine (3-NT), as a stable biomarker in the human body, is closely related to a variety of diseases. Therefore, the detection of 3-NT is of important significance for human disease monitoring. In addition, under the same dimension, the influence of CPs with different metals on 3-NT detection still has important research value. Herein, we successfully synthesized two new 2D coordination polymers (CPs), namely [M(L)(BTEC) 0.5 ]·H 2 O (M = Cd for CP 1 , M = Zn for CP 2), by using the bis(pyridyl)-bis(amide) ligand L [(E)-4,4′-(ethene-1,2-diyl)bis[(N -pyridin-3-yl)benzamide] as the main ligand and 1,2,4,5-benzenetetracarboxylic acid (H 4 BTEC) as the auxiliary ligand under hydrothermal conditions. CPs 1 – 2 can be used as fluorescent sensors to effectively detect 3-NT, and have the advantages of excellent stability, anti-interference, recyclability and low limits of detection (LODs). The influence of the different metals in the CPs on the fluorescence sensing 3-NT was discussed, and the difference of sensing mechanism and performance of CPs 1 – 2 on 3-NT were studied in detail, which provided a reference for the design of CPs and the influencing factors of 3-NT detection. [ABSTRACT FROM AUTHOR]

In this paper, we consider the problem of quickly detecting an abrupt change in linear regression models. Specifically, an observer sequentially obtains a sequence of observations, whose underlying linear model changes at an unknown time. Moreover, the pre-change linear model is perfectly known by the observer but the post-change linear model is unknown. The observer aims to design an efficient online algorithm to detect the presence of the change via his sequential observations. Based on different assumptions on the change-point, both non-Bayesian and Bayesian problem formulations are considered. In the non-Bayesian setting, the change-point is modeled as a fixed but unknown constant. Two performance metrics, namely the worst case detection delay and the average run length to false alarm, are adopted to evaluate the performance of detection algorithms. In the Bayesian setting, the change-point is modeled as a geometrically distributed random variable. For this case, the average detection delay and the probability of false alarm are used as performance metrics. We propose a novel algorithm, namely the parallel-sum algorithm, for the purpose of change detection. For both setups, we show that the proposed algorithm has a low computational complexity while still offering a good performance in terms of the performance metrics of the respective setting. [ABSTRACT FROM AUTHOR]

Objective: The objective of this study is to evaluate the postoperative analgesic effect of a combination of ropivacaine and dexmedetomidine for ultrasound-guided fascia iliaca compartment block (FICB) after knee arthroscopy. Materials and Methods: Forty patients scheduled for knee arthroscopy were randomized to receive either 30 ml of 0.25% ropivacaine alone (Group A, n = 20) or combined with dexmedetomidine 1 μg/kg (Group B, n = 20). Pain intensity was evaluated using the visual analogue scale (VAS), at rest and during activity at 4, 6, 8, 12, and 24 h after surgery. Level of consciousness was evaluated using the Ramsay sedation score. Time to first analgesic request after surgery, the dose of analgesic used in the first 24 h after surgery, variation of heart rate, and adverse reactions were also recorded. Results: VAS scores at 6 and 12 h after surgery were significantly lower in Group B compared to Group A (P < 0.05). No significant difference was observed in the Ramsay sedation score or time to first analgesic request after surgery (P > 0.05). The total dose of analgesic used in the first 24 h after surgery was higher in Group A than in Group B. The incidence of bradycardia was higher in Group B compared to Group A. No adverse reactions were observed in either group. Conclusion: FICB with a combination of ropivacaine and dexmedetomidine resulted in significant reduction of VAS scores with lower postoperative analgesic requirement after arthroscopic knee surgery. No adverse reactions or complications were noted except for lower heart rate in Group B patients. [ABSTRACT FROM AUTHOR]

In this paper, we present several necessary and sufficient conditions to ensure an ordinal sum of t-norms is still a t-norm on bounded lattices. For a fixed or an arbitrary bounded sublattice of a bounded lattice, we provide a direct characterization theorem, respectively. Meanwhile, we extend these results to the ordinal sum for a family of pairwise disjoint bounded sublattices. Furthermore, we investigate ordinal sum of t-norms on product lattices and reveal that there exist ordinal sum t-norms on non-trivial bounded sublattices of product lattices, which is different from the previous results of ordinal sum of t-norms defined on subintervals. [ABSTRACT FROM AUTHOR]

The primary purpose of this paper is to investigate a family of elliptic systems of linear elasticity with rapidly oscillating periodic coefficients, arising in the theory of homogenization in Lipschitz domains. As a consequence, for d ≥ 4 , we prove that the L p Neumann and L p Dirichlet boundary value problems for systems of second order linear elasticity are uniquely solvable for 2 ( d − 1 ) d + 1 − δ < p < 2 + δ and 2 − δ < p < 2 ( d − 1 ) d − 3 + δ respectively. [ABSTRACT FROM AUTHOR]

In this paper, we show that the consistent Hoare powerdomain H c ( P ) over a dcpo P exists and is isomorphic to a special Scott closed subset of Γ ( P ) relative to the Scott topology σ ( Γ ( P ) ) , where Γ ( P ) is the collection of all nonempty Scott closed subsets of P ordered by the set-theoretic inclusion relation. [ABSTRACT FROM AUTHOR]

Geometric-optical (GO) model suitable for forest plantation (GOFP) is a GO model for forest plantations at the stand level developed in this study based on a four-scale GO model a Geometric-Optical Model for Sloping Terrains-II (GOST2), which simulates the bidirectional reflectance distribution function (BRDF) for natural forest canopies. In most previous GO models, tree distributions are often assumed to meet the Poisson or Neyman model in a forest; therefore, these models are suitable for simulating BRDF for natural forest canopies. However, in forest plantations, tree distributions are proven to meet the hypergeometric model rather than the Poisson or Neyman model at the stand level. GOFP, in which the tree distributions are described using the hypergeometric model, is proposed to simulate the bidirectional reflectance factor (BRF) of forest plantations at the stand level. The area ratios of the four scene components (sunlit foliage, sunlit ground, shaded foliage, and shaded ground) of GOFP compare well with those simulated by a 3-D canopy visualization technique. A comparison is also made against discrete anisotropic radiative transfer, showing that GOFP has the ability to simulate BRF of forest plantations. Another comparison is made against operational land imager and Moderate Resolution Imaging Spectroradiometer surface reflectance, showing that GOFP with the hypergeometric model outperforms GOST2 with the Poisson and Neyman models. The results further show that the differences in BRFs between GOFP and GOST2 pronouncedly increase with the difference between the reflectance of sunlit foliage ( RT ) and the reflectance of sunlit ground ( RG ), as well as the distances among trees and the number of crowns in a forest plantation, suggesting that GOFP significantly outperforms GOST2 for simulating BRF of forest plantations. [ABSTRACT FROM PUBLISHER]

This paper is concerned with a family of elliptic systems of linear elasticity with rapidly oscillating periodic coefficients, arising in the theory of homogenization. We establish uniform optimal regularity estimates for solutions of Neumann problems in a bounded Lipschitz domain with L boundary data. The proof relies on a boundary Korn inequality for solutions of systems of linear elasticity and uses a large-scale Rellich estimate obtained in Shen (Anal PDE, ). [ABSTRACT FROM AUTHOR]

For a family of second-order parabolic systems with bounded measurable, rapidly oscillating and time-dependent periodic coefficients, we investigate the sharp convergence rates of weak solutions in L 2 . Both initial-Dirichlet and initial-Neumann problems are studied. [ABSTRACT FROM AUTHOR]

Spectrum sensing is a key technology enabling the cognitive radio system. In this paper, the problem of how to quickly and accurately find an unoccupied channel from a large amount of potential channels is considered. The cognitive radio system under consideration is equipped with a narrow band sensor, hence it can only sense those potential channels in a sequential manner. In this scenario, we propose a novel two-stage mixed-observation sensing strategy. In the first stage, which is named as scanning stage, the sensor observes a linear combination of the signals from a pair of channels. The purpose of the scanning stage is to quickly identify a pair of channels such that at least one of them is highly likely to be unoccupied. In the second stage, which is called refinement stage, the sensor only observers the signal from one of those two channels identified from the first stage, and selects one of them as the unoccupied channel. The problem under this setup is an ordered two concatenated Markov stopping time problem. The optimal solution is solved using the tools from the multiple stopping time theory. It turns out that the optimal solution has a rather complex structure, hence a low complexity algorithm is proposed to facilitate the implementation. In the proposed low complexity algorithm, the cumulative sum test is adopted in the scanning stage and the sequential probability ratio test is adopted in the refinement stage. The performance of this low complexity algorithm is analyzed when the presence of unoccupied channels is rare. Numerical simulation results show that the proposed sensing strategy can significantly reduce the sensing time when the majority of potential channels are occupied. [ABSTRACT FROM PUBLISHER]

Background: The use of dexmedetomidine may have benefits on the clinical outcomes of cardiac surgery. We conducted a meta-analysis comparing the postoperative complications in patients undergoing cardiac surgery with dexmedetomidine versus other perioperative medications to determine the influence of perioperative dexmedetomidine on cardiac surgery patients. Methods: Randomized or quasi-randomized controlled trials comparing outcomes in patients who underwent cardiac surgery with dexmedetomidine, another medication, or a placebo were retrieved from EMBASE, PubMed, the Cochrane Library, and Science Citation Index. Results: A total of 1702 patients in 14 studies met the selection criteria among 1,535 studies that fit the research strategy. Compared to other medications, dexmedetomidine has combined risk ratios of 0.28 (95% confidence interval [CI] 0.15, 0.55, P = 0.0002) for ventricular tachycardia, 0.35 (95% CI 0.20, 0.62, P = 0.0004) for postoperative delirium, 0.76 (95% CI 0.55, 1.06, P = 0.11) for atrial fibrillation, 1.08 (95% CI 0.74, 1.57, P = 0.69) for hypotension, and 2.23 (95% CI 1.36, 3.67, P = 0.001) for bradycardia. In addition, dexmedetomidine may reduce the length of intensive care unit (ICU) and hospital stay. Conclusions: This meta-analysis revealed that the perioperative use of dexmedetomidine in patients undergoing cardiac surgery can reduce the risk of postoperative ventricular tachycardia and delirium, but may increase the risk of bradycardia. The estimates showed a decreased risk of atrial fibrillation, shorter length of ICU stay and hospitalization, and increased risk of hypotension with dexmedetomidine. [ABSTRACT FROM AUTHOR]

We study the L p regularity problem for the stationary Stokes system on Lipschitz domains. For any p > 2 we show that a weak reverse Hölder inequality with exponent p is both necessary and sufficient for the solvability of the regularity problem with data in W 1 , p ( ∂ Ω ) ∩ L n p ( ∂ Ω ) . We also obtain the W 1 , p ( Ω ) estimate ‖ ∇ u ‖ L p ( Ω ) + ‖ q ‖ L p ( Ω ) ≤ ‖ f ‖ L p ( Ω ) in a bounded Lipschitz domain Ω ⊂ R d for solutions to the Dirichlet problem Δ u = ∇ q + div ( f ) , div ( u ) = 0 in Ω and u = 0 on ∂Ω, where | 1 p − 1 2 | < 1 2 d + ε . [ABSTRACT FROM AUTHOR]

We consider linear regression problems for which the underlying model undergoes multiple changes. Our goal is to estimate the number and locations of change-points that segment available data into different regions, and further produce sparse and interpretable models for each region. To address challenges of the existing approaches and to produce interpretable models, we propose a sparse group Lasso based approach for linear regression problems with change-points. Under certain mild assumptions and a properly chosen regularization term, we prove that the solution of the proposed approach is asymptotically consistent. In particular, we show that the estimation error of linear coefficients diminishes, and the locations of the estimated change-points are close to those of true change-points. We further propose a method to choose the regularization term so that the results mentioned above hold. In addition, we show that the complexity of the proposed algorithm is much smaller than those of existing approaches. Numerical examples are provided to validate the analytical results. [ABSTRACT FROM PUBLISHER]

Bulk metallic glasses are known to have a close relationship with some special clusters and can be designed within the framework of the cluster-plus-glue-atom model. So the key issue in applying this model lies in the determination of the appropriate clusters. In this paper, the atomic density radial distribution is proposed to define the closed-packed cluster. As examples B–Fe, B–Co and B–Ni alloy phases are analyzed from the viewpoint of coordination polyhedral clusters. Then capped octahedral antiprism B 3 (Fe, Co, Ni) 8 clusters are highlighted because of the most close packing. Finally the relationship between B 3 (Fe, Co, Ni) 8 clusters and bulk metallic glass formation is discussed and indeed verified by experiments. [ABSTRACT FROM AUTHOR]

In this paper, Bayesian quickest change detection problems with sampling right constraints are considered. In particular, there is a sequence of random variables whose probability density function will change at an unknown time. The goal is to detect this change in a way such that a linear combination of the average detection delay and the false alarm probability is minimized. Two types of sampling right constrains are discussed. The first one is a limited sampling right constraint, in which the observer can take at most \(N\) observations from this random sequence. Under this setup, we show that the cost function can be written as a set of iterative functions, which can be solved by Markov optimal stopping theory. The optimal stopping rule is shown to be a threshold rule. An asymptotic upper bound of the average detection delay is developed as the false alarm probability goes to zero. This upper bound indicates that the performance of the limited sampling right problem is close to that of the classic Bayesian quickest detection for several scenarios of practical interest. The second constraint discussed in this paper is a stochastic sampling right constraint, in which sampling rights are consumed by taking observations and are replenished randomly. The observer cannot take observations if there are no sampling rights left. We characterize the optimal solution, which has a very complex structure. For practical applications, we propose a low complexity algorithm, in which the sampling rule is to take observations as long as the observer has sampling rights left and the detection scheme is a threshold rule. We show that this low complexity scheme is first order asymptotically optimal as the false alarm probability goes to zero. [ABSTRACT FROM AUTHOR]

Spherical ZnS/Au nanocomposites have been synthesized through a fast one-step microwave-hydrothermal route. Surfactant polyvinylpyrrolidone (PVP) was used as shape modifier to control the size of products. The use of different sulfur sources also resulted in nanospheres with different sizes. The formation mechanism of the nanocomposites is discussed. The UV-vis and photoluminescence properties of the as-prepared nanocomposites with different Au doping concentrations showed tunable UV and visible emission intensity. [ABSTRACT FROM AUTHOR]

Abstract: Aerosol condensational growth in a fluid field, including water vapor depletion and latent heat of condensation, is studied by a newly developed model coupling aerosol condensation with fluid dynamics. This model couples the fluid dynamics (via ANSYS FLUENT) and a time-dependent model [1] developed for nonsteady state, nonisothermal conditions. Mass and heat are effectively conserved throughout the computational domain with changes driven by aerosol condensation and evaporation. In turn, these changes promote fluid movement and its evolution. Communications between the air parcel, inside which the aerosol particles are introduced, and the outside environment are allowed by means of mass and heat transfer. Comparison between results of models with and without computational fluid dynamics (CFD) shows that the fluid movement due to aerosol condensation can have significant impact on the aerosol growth. By comparing the growth of both monodisperse and polydisperse (NH4)2SO4 particles of different number densities at various initial supersaturation conditions, particle number concentrations are shown to have great impact on the aerosol condensational growth with mass and heat exchange between the inside and outside of the air parcel. [Copyright &y& Elsevier]

Abstract: A computational solution of the coupled heat and mass transport equations for aerosols, which may be either single component or multicomponent, in a finite volume is developed under nonsteady state and nonisothermal conditions. It is capable of computing the temperature and vapor density profile around the droplets. Both mass and heat are conserved effectively in the volume, which enables this computational model to describe time-dependent, competitive, aerosol condensation and evaporation. Calculations for pure water particles and sodium nitrate particles in the presence of water vapor are performed. By comparing the particle growth for different number densities at various initial supersaturation conditions, both the initial saturations and particle number concentrations are shown to have great impact on the aerosol condensational growth. Detailed discussions on the change of bulk temperature, bulk relative humidity (RH), total surface area and volume are given. [Copyright &y& Elsevier]

Abstract: We study estimates in Lipschitz domains for second order elliptic equations and systems of divergence form with real-valued, bounded, measurable coefficients. For any fixed , we prove that a weak reverse Hölder inequality implies the estimates for solutions with Neumann boundary conditions. As a result, we are able to show that if the coefficient matrix of elliptic equation is symmetric and in , the estimate holds for if , and for if , and for elliptic systems the estimate is true for . [Copyright &y& Elsevier]

Abstract: Let be a family of elliptic systems of linear elasticity with rapidly oscillating periodic coefficients. We obtain the uniform estimate in a Lipschitz domain Ω in for solutions to the Dirichlet problem: in Ω and on ∂Ω, where and C, are constants independent of . The ranges are sharp for or 3. [Copyright &y& Elsevier]

Abstract: We show that the Neumann problem for Laplace''s equation in a convex domain Ω with boundary data in is uniquely solvable for . As a consequence, we obtain the Helmholtz decomposition of vector fields in . [Copyright &y& Elsevier]

ABSTRACT A dual-wideband bandstop filter using stepped impedance coupled-lines is proposed. Due to the couplings of the coupled-lines, two transmission zeros are introduced into each stopband, leading to enhanced selectivity and extended rejection bandwidths. To validate the proposed structure, one prototype filter has been fabricated and measured. The results show the stopbands with −10 dB fractional bandwidth of 83% and 30% at 1.2 GHz and 4.2 GHz, respectively. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:2304-2306, 2015 [ABSTRACT FROM AUTHOR]

Abstract: The pressure and internal energy data at different densities of the supersaturated Argon vapor at the reduced temperatures 0.7 and 0.8 are obtained by the restricted canonical ensemble Monte Carlo simulation method [D.S. Corti, P. Debenedetti, Chem. Eng. Sci. 49 (1994) 2717]. In order to maintain the system in its one-phase state, different constraints on the density fluctuations have been imposed, varying with densities approaching and beyond the spinodal. The results are comparable with a molecular dynamics simulation study [A. Linhart, C.C. Chen, J. Vrabec, H. Hasse, J. Chem. Phys. 122 (2005) 144506] on the same system. The current study verifies the conclusion drawn by the simulation work that clustering of Argon atoms exists even in the vicinity of the spinodal. Compared with molecular dynamics simulations, our method can give the equilibrium properties of a metastable fluid, for example internal energies. [Copyright &y& Elsevier]

The properties of synthesized side-chain liquid crystalline polymer (SCLCP)/liquid crystal (LC)/chiral dopant composites having a chiral nematic (N*) phase at room temperature were investigated by polarized optical microscopy (POM) and a UV/VIS/NIR spectrophotometer. The composite exhibited a planar texture after it was filled into cells under homogeneous boundary conditions and it was transparent. When an electric field was applied to the composite, a focal conic texture was formed and the composite became light scattering. After the electric field was turned off, the light-scattering state remained stable for some time, i.e. the light-scattering state exhibited a memory effect. The focal conic texture changed into the planar texture when the composite was heated and the composite became transparent again. Therefore, the composite had electrically induced and thermally erased properties. The SCLCP had some influence on the memory effect and on the thermo-electro-optical properties of the composite. [ABSTRACT FROM AUTHOR]

PbWO4 nanostructures with different morphologies, such as polyhedral, spindle-like, and dot-shaped, have been successfully synthesized via a mild sonochemical route from an aqueous solution of lead acetate and sodium tungstate in the presence of complexing reagent NTA. Reaction conditions, such as pH value and the concentration of complexing reagent, were found to have close relation with the morphologies of final products. The ultrasound-induced oriented attachment growth mechanism has been proposed for the possible formation mechanism of spindle-like sample. Raman and room-temperature photoluminescence of PbWO4 samples with different morphologies have also been investigated. PbWO4 nanostructures with different morphologies, such as polyhedral, spindle-like, and dot-shaped, have been successfully synthesized via a mild sonochemical route. [ABSTRACT FROM AUTHOR]