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With the exponential growth in data density and user ends of wireless networks, fronthaul is tasked with supporting aggregate bandwidths exceeding thousands of gigahertz while accommodating high-order modulation formats. However, it must address the bandwidth and noise limitations imposed by optical links and devices in a cost-efficient manner. Here we demonstrate a high-fidelity fronthaul system enabled by self-homodyne digital-analog radio-over-fiber superchannels, using a broadband electro-optic comb and uncoupled multicore fiber. This self-homodyne superchannel architecture not only offers capacity boosting but also supports carrier-recovery-free reception. Our approach achieves a record-breaking 15,000 GHz aggregated wireless bandwidth, corresponding to a 0.879 Pb/s common public radio interface (CPRI) equivalent data rate. Higher-order formats up to 1,048,576 quadrature-amplitude-modulated (QAM) are showcased at a 100 Tb/s class data rate. Furthermore, we employ a packaged on-chip electro-optic comb as the sole optical source to reduce the cost, supporting a data rate of 100.5 Tb/s with the 1024-QAM format. These demonstrations propel fronthaul into the era of Pb/s-level capacity and exhibit the promising potential of integrated-photonics implementation, pushing the boundaries to new heights in terms of capacity, fidelity, and cost. Here the authors propose a self-homodyne fronthaul architecture, utilizing DA-RoF super channels and multicore fiber, paving the way for the Pb/s era in fronthaul transmission, enabling ultra-highspeed Internet access. The remarkable data speeds reaching 0.879 Pb/s and the 256-QAM format make it possible for 150,000 5G channels to be accessed simultaneously. [ABSTRACT FROM AUTHOR]

Summary: Osteoporosis-pseudoglioma syndrome (OPPG) and LRP5 high bone mass (LRP5-HBM) are two rare bone diseases with opposite clinical symptoms caused by loss-of-function and gain-of-function mutations in LRP5. Bisphosphonates are an effective treatment for OPPG patients. LRP5-HBM has a benign course, and age-related bone loss is found in one LRP5-HBM patient. Purpose: Low-density lipoprotein receptor-related protein 5 (LRP5) is involved in the canonical Wnt signaling pathway. The gain-of-function mutation leads to high bone mass (LRP5-HBM), while the loss-of-function mutation leads to osteoporosis-pseudoglioma syndrome (OPPG). In this study, the clinical manifestations, disease-causing mutations, treatment, and follow-up were summarized to improve the understanding of these two diseases. Methods: Two OPPG patients and four LRP5-HBM patients were included in this study. The clinical characteristics, biochemical and radiological examinations, pathogenic mutations, and structural analysis were summarized. Furthermore, several patients were followed up to observe the treatment effect and disease progress. Results: Congenital blindness, persistent bone pain, low bone mineral density (BMD), and multiple brittle fractures were the main clinical manifestations of OPPG. Complex heterozygous mutations were detected in two OPPG patients. The c.1455G > T mutation in exon 7 was first reported. During the follow-up, BMD of two patients was significantly improved after bisphosphonate treatment. On the contrary, typical clinical features of LRP5-HBM included extremely high BMD without fractures, torus palatinus and normal vision. X-ray showed diffuse osteosclerosis. Two heterozygous missense mutations were detected in four patients. In addition, age-related bone loss was found in one LRP5-HBM patient after 12-year of follow-up. Conclusion: This study deepened the understanding of the clinical characteristics, treatment, and follow-up of OPPG and LRP5-HBM; expanded the pathogenic gene spectrum of OPPG; and confirmed that bisphosphonates were effective for OPPG. Additionally, it was found that Ala242Thr mutation could not protect LRP5-HBM patients from age-related bone loss. This phenomenon deserves further study. [ABSTRACT FROM AUTHOR]

New human life begins in the uterus in a period of both extreme plasticity and sensitivity to environmental disturbances. The fetal stage is also a vital period for central nervous system development, with experiences at this point profoundly and permanently shaping brain structure and function. As such, some brain disorders may originate in utero. Glucocorticoids, a class of essential stress hormones, play indispensable roles in fetal development, but overexposure may have lasting impacts on the brain. In this review, we summarize data from recent clinical and non-clinical studies regarding alterations in fetal brains due to prenatal glucocorticoid overexposure that are associated with nervous system disorders. We discuss relevant changes to brain structure and cellular functions and explore the underlying molecular mechanisms. In addition, we summarize factors that may cause differential outcomes between varying brain regions, and outline clinically feasible intervention strategies that are expected to minimize negative consequences arising from fetal glucocorticoid overexposure. Finally, we highlight the need for experimental evidence aided by new technologies to clearly determine the effects of excessive prenatal glucocorticoid exposure. This review consolidates diverse findings to help researchers better understand the relationship between the prenatal glucocorticoid overexposure and the effects it has on various fetal brain regions, promoting further development of critical intervention strategies. [ABSTRACT FROM AUTHOR]

Herpes simplex virus type 1 (HSV-1) plays an important role in the field of gene therapy and viral vaccines, especially as an oncolytic virus. However, the mass production of HSV-1 viral vectors remains a challenge in the industry. In this study, a microcarrier-mediated serum-reduced medium culture was used to improve the bioprocess of HSV-1 production and increase HSV-1 yields. The composition of the culture media, which included a basal medium, serum concentration, and glutamine additive, was optimized. The process was successfully conducted in a 1 L bioreactor, and virus production was threefold greater than that of conventional processes with a 10% serum medium. The bead-to-bead transfer process was also developed to further increase scalability. In spinner flasks, the detachment rate increased from 49.4 to 80.6% when combined agitation was performed during digestion; the overall recovery proportion increased from 37.9 to 71.1% after the operational steps were optimized. Specifically, microcarrier loss was reduced during aspiration and transfer, and microcarriers and detached cells were separated with filters. Comparable cell growth was achieved with the baseline process using 2D culture as the inoculum by exchanging the subculture medium. To increase virus production after bead-to-bead transfer, critical parameters, including shear stress during digestion, TrypLE and EDTA concentrations in the subculture, and the CCI, were identified from 47 parameters via correlation analysis and principal component analysis. The optimized bead-to-bead transfer process achieved an average of 90.4% overall recovery and comparable virus production compared to that of the baseline process. This study is the first to report the optimization of HSV-1 production in Vero cells cultured on microcarriers in serum-reduced medium after bead-to-bead transfer. Key points: • An HSV-1 production process was developed that involves culturing in serum-reduced medium, and this process achieved threefold greater virus production than that of traditional processes. • An indirect bead-to-bead transfer process was developed with over 90% recovery yield in bioreactors. • HSV-1 production after bead-to-bead transfer was optimized and was comparable to that achieved with 2D culture as inoculum. [ABSTRACT FROM AUTHOR]

This work focuses on the optimal control design for suppressing the singularity formation in chemotaxis governed by the parabolic-elliptic Patlak–Keller–Segel (PKS) system via flow advection. The main idea of this work lies in utilizing flow advection for enhancing diffusion as to control the nonlinear behavior of the system. The objective is to determine an optimal strategy for adjusting flow strength so that the possible finite time blow-up of the solution can be suppressed. Rigorous proof of the existence of an optimal solution and derivation of first-order optimality conditions for solving such a solution are presented. Spline collocation methods are employed for solving the optimality conditions. Numerical experiments based on 2D cellular flows in a rectangular domain are conducted to demonstrate our ideas and designs. [ABSTRACT FROM AUTHOR]

Localization is a fundamental issue in wireless sensor networks (WSNs). Localization with mobile anchors is one of the most efficient ways to deploy sensor nodes and locate them. Due to the limitations of cost and power consumption in WSNs, it is necessary to study the path planning of mobile anchor nodes, which is conducive to rapid localization with low energy consumption. This paper designs two path planning methods named TSCAN-R and TSCAN-E based on two mobile anchor nodes. They not only have short path lengths but can also overcome the problem of collinearity. Furthermore, a modified curve fitting-based localization method (MCFLM) is proposed. This method matches the distance between mobile anchor nodes in certain trajectories and unknown nodes and then infers the localization of the unknown nodes based on poles of distance curves. Simulation results indicate that MCFLM-based TSCAN-R and TSCAN-E have better localization accuracy and shorter path length than other methods. [ABSTRACT FROM AUTHOR]

Access to the internet by mobile terminals relies on the transmission of information from the optical fibre backbone to wireless networks. Fronthaul, as the last mile of fibre-wireless convergence, determines the overall transmission performance in terms of capacity and fidelity. Orders-of-magnitude increases in both bandwidth and signal-to-noise ratio (SNR) are urgently desired to cope with the large growth in wireless traffic. Here we demonstrate a self-homodyne digital-analogue radio-over-fibre fronthaul using cloned optical frequency combs that meets these needs. The approach simultaneously supports an unprecedented 14.1 Tb s−1 common public radio interface equivalent data rate and a 1,024 quadrature-amplitude-modulated format. The clone-comb configuration, which possesses the properties of frequency and phase locking, is the key to enabling a high-performance coherent digital-analogue radio-over-fibre system. Besides exploiting the quadruple capacity for a single channel thanks to coherent detection, the clone-comb approach can also provide multiple parallel channels concurrently, boosting the overall data throughput. We further demonstrate the potential of the technique, showing its ability to transmit 65,536 quadrature-amplitude-modulated signals and a data rate of 32.8 Tb s−1. Our architecture is promising for fibre-based and free-space optical fronthaul, bringing full-band and coherent-lite access networks into reach. The use of clone combs provides very high-capacity radio-over-fibre data transmission with high-order modulation formats. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the effect of total parathyroidectomy (tPTx) on malnutrition and inflammation in patients on maintenance dialysis (MHD) having secondary hyperparathyroidism (SHPT). Methods: Twenty-five patients on MHD having SHPT who were being treated with tPTx were selected, and changes in their general condition (dry body mass), parathyroid hormone (PTH) and calcium levels, nutrition state (hemoglobin, hematocrit, serum albumin, and total iron binding capacity), and inflammatory status [serum C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor (TNF-α), and the malnutrition–inflammation score (MIS)] were observed at 12, 24, and 36 months postoperatively. Results: Compared with the preoperative period, the dry body mass increased at 12, 24, and 36 months postoperatively (P < 0.01), hemoglobin, hematocrit, and serum albumin increased significantly (P < 0.01), whereas calcium, phosphorus, and PTH levels decreased significantly (P < 0.01). Serum CRP, IL-6, and TNF-α levels were significantly decreased at 12, 24, and 36 months after surgery (P < 0.01). Furthermore, MIS was reduced as well but to a lesser extent (P < 0.01). Conclusion: tPTx effectively reduced MIS in maintenance dialysis patients, and the alleviated malnutrition and improved inflammatory status may contributed to improving the quality of life of patients on MHD with SHPT. [ABSTRACT FROM AUTHOR]

The emergence of parallel convolution-operation technology has substantially powered the complexity and functionality of optical neural networks (ONN) by harnessing the dimension of optical wavelength. However, this advanced architecture faces remarkable challenges in high-level integration and on-chip operation. In this work, convolution based on time-wavelength plane stretching approach is implemented on a microcomb-driven chip-based photonic processing unit (PPU). To support the operation of this processing unit, we develop a dedicated control and operation protocol, leading to a record high weight precision of 9 bits. Moreover, the compact architecture and high data loading speed enable a preeminent photonic-core compute density of over 1 trillion of operations per second per square millimeter (TOPS mm−2). Two proof-of-concept experiments are demonstrated, including image edge detection and handwritten digit recognition, showing comparable processing capability compared to that of a digital computer. Due to the advanced performance and the great scalability, this parallel photonic processing unit can potentially revolutionize sophisticated artificial intelligence tasks including autonomous driving, video action recognition and image reconstruction. Optical neural networks face remarkable challenges in high-level integration and on-chip operation. In this work the authors enable optical convolution utilizing time-wavelength plane stretching approach on a microcomb-driven chip-based photonic processing unit. [ABSTRACT FROM AUTHOR]

Chronic stress activates the sympathetic nervous system (SNS) and hypothalamic–pituitary–adrenal (HPA) axis to aggravates tumorigenesis and development. Although the importance of SNS and HPA in maintaining homeostasis has already attracted much attention, there is still a lot remained unknown about the molecular mechanisms by which chronic stress influence the occurrence and development of tumor. While some researches have already concluded the mechanisms underlying the effect of chronic stress on tumor, complicated processes of tumor progression resulted in effects of chronic stress on various stages of tumor remains elusive. In this reviews we concluded recent research progresses of chronic stress and its effects on premalignancy, tumorigenesis and tumor development, we comprehensively summarized the molecular mechanisms in between. And we highlight the available treatments and potential therapies for stressed patients with tumor. [ABSTRACT FROM AUTHOR]

This paper is concerned with a bilinear control problem for enhancing convection-cooling via an incompressible velocity field. Both optimal open-loop control and closed-loop feedback control designs are addressed. First and second order optimality conditions for characterizing the optimal solution are discussed. In particular, the method of instantaneous control is applied to establish the feedback laws. Moreover, the construction of feedback laws is also investigated by directly utilizing the optimality system with appropriate numerical discretization schemes. Computationally, it is much easier to implement the closed-loop feedback control than the optimal open-loop control, as the latter requires to solve the state equations forward in time, coupled with the adjoint equations backward in time together with a nonlinear optimality condition. Rigorous analysis and numerical experiments are presented to demonstrate our ideas and validate the efficacy of the control designs. [ABSTRACT FROM AUTHOR]

A novel method is proposed to estimate direction of arrival (DOA) with uniform circular array (UCA) in the presence of phase errors. Inspired by the rank reduction (RARE) theory in the spatial domain, which employs the extra sensors to construct the necessary condition for RARE. i.e., rank reduction vector, a reduction in the radius of UCA is considered for the creation of the rank reduction vector that is only related to the DOA in the UCA mode domain. This indicates that the DOA and the channel phase errors coupling in the steering vector in the spatial domain can be decoupled in the UCA mode domain, and then the optimization function only related to the phase errors is formulated with the rank reduction vector based on the RARE theory employed in the UCA mode domain. Then with the channel phase errors calibrated, the DOA can be estimated via UCA-ESPRIT. The proposed method requires no redundant sensors or calibration sources. Also, it avoids the multi-dimensional iteration, which is superior to the Schur-product based method as it has a larger tolerance for the array aperture. Results verify its effectiveness. [ABSTRACT FROM AUTHOR]

We study a temperature and velocity output tracking problem for a two-dimensional room model with the fluid dynamics governed by the linearized translated Boussinesq equations. Additionally, the room model includes finite-dimensional models for actuation and sensing dynamics; thus, the complete model dynamics are governed by an ODE–PDE–ODE cascade. As the main contribution, we design a low-dimensional internal model-based controller for robust output tracking of the room model. The controller's performance is demonstrated through a numerical example. [ABSTRACT FROM AUTHOR]

Activated carbon has attracted much attention in the remediation of heavy metal pollution; however, it is still a challenge to explore a cheap and efficient activated carbon for the removal of chromium(VI) from water. In this study, based on the concept of "treating pollution with waste," a high adsorption performance activated carbon was prepared by in situ carbonization and activation of soybean straw residue with potassium hydroxide as a chemical activator for the purpose of enhancing Cr(VI) removal capacity. The structure and property of the generated soybean straw-based activated carbon (SSAC) was characterized by SEM, FTIR, BET analysis, and XPS. The influence factors (i.e., pH, adsorbent dosage, initial Cr(VI) concentration) on the removal of Cr(VI) by SSAC were studied by batch experiments. Results revealed that SSAC not only exhibited porosity with a huge specific surface area of 1800.28 m2 g−1 but also had abundant electron-donating groups (such as C = C, C–OH) on the surface to reduce Cr(VI) to Cr(III), which both promoted a high adsorption capability with the maximum Cr(VI) adsorption capacity of 294.12 mg g−1 at pH = 2. The adsorption process was in accordance with the Langmuir model and the pseudo second-order model corresponding to monolayer and chemical adsorption, respectively, and it was spontaneous and endothermic. As for the study of mechanism, reduction and electrostatic adsorption may dominate the removal of Cr(VI) by SSAC. All these results indicated that SSAC had the potential to efficiently remove Cr(VI) in aqueous solutions, which may be a promising adsorbent to provide a potential solution for solving the problems of heavy metal pollution and straw agricultural residue disposal. [ABSTRACT FROM AUTHOR]

The piecewise affine (PWA) model represents an attractive model structure for approximating nonlinear systems. In this paper, a procedure for obtaining the PWA model of the tire nonlinear cornering properties is introduced. In this approach, the highly nonlinear dynamic of the tire cornering properties is well approximated by a set of affine maps which relate inputs and outputs. These maps are defined in disjunctive regions in the regression space, itself composed of system inputs and outputs. The tire cornering properties tests are firstly carried out through a high-performance flat-plate test bench, thus the experimental data which can accurately reflect the tire cornering properties is obtained. On this basis, the PWA identification of the tire cornering properties is composed of the data clustering, the parameter estimation of the affine submodels and the calculation of the hyperplane coefficient matrices, which are respectively achieved by means of fuzzy c-means clustering, weighted least-squares and support vector machines. Finally, to verify the PWA model accuracy in approximating the tire nonlinear cornering properties, the comparison between the simulation results of the PWA identification model and the experimental data is conducted and the comparison results are analyzed. [ABSTRACT FROM AUTHOR]

Negative symptoms in schizophrenia strongly contribute to poor functional outcomes, however its pathogenesis is still unclear. Here, we found that histamine H1 receptor (H1R) expression in basal forebrain (BF) cholinergic neurons was decreased in patients with schizophrenia having negative symptoms. Deletion of H1R gene in cholinergic neurons in mice resulted in functional deficiency of cholinergic projections from the BF to the prefrontal cortex and in the formation of sensorimotor gating deficit, social impairment and anhedonia-like behavior. These behavioral deficits can be rescued by re-expressing H1R or by chemogenetic activation of cholinergic neurons in the BF. Direct chemogenetic inhibition of BF cholinergic neurons produced such behavioral deficits and also increased the susceptibility to hyperlocomotion. Our results suggest that the H1R deficiency in BF cholinergic neurons is critical for sensorimotor gating deficit, social impairments and anhedonia-like behavior. This finding may help to understand the genetic and biochemical bases of negative symptoms in schizophrenia. Social impairment and anhedonia are common negative symptoms in patients with schizophrenia. Here, the authors show that the histamine H1 receptor in cholinergic neurons in the basal forebrain has a critical role in sensorimotor gating, social behaviour, and anhedonia-like behaviour in mice. [ABSTRACT FROM AUTHOR]

In this paper, we apply the circle method to study the average behavior of the triple divisor function over values of quadratic form n 1 2 + n 2 2 + ⋯ + n l 2 with l ⩾ 3. We improve and generalize previous results. [ABSTRACT FROM AUTHOR]

Background: Tumor cell-derived exosomes (TEXs) have been widely used to induce antitumor immune responses in animal models and clinical trials. Similarly, leukemia cell-derived exosomes (LEXs) can induce antileukemia immune responses in animal models. However, the antileukemia immunity induced by LEXs is less effective, which may be due to an inadequate costimulatory capacity. Methods: In this study, we transduced L1210 leukemia cells with a lentiviral vector encoding two B7 costimulatory molecules (CD80, CD86) and obtained LEXs that highly expressed CD80 and CD86. The antileukemia immune response derived from these LEXs was examined in vitro and in vivo in animal models. Results: We found that B7 gene-modified LEXs, including LEX-CD80, LEX-CD86, and LEX-8086, could significantly boost the expression of CD80 and CD86 in dendritic cells (DCs) and promote the secretion of functional cytokines such as TNF-α and IL-12. Moreover, these B7 gene-modified LEXs, particularly LEX-CD8086, could effectively induce CD4+ T cell proliferation, Th1 cytokine secretion, and an antigen-specific anti-leukemia cytotoxic T lymphocyte (CTL) response. Additional animal studies indicated that immunization with B7 gene-modified LEXs, in particular LEX-CD8086, could significantly retard tumor growth compared to the control LEXnull group. Conclusions: This study sheds light on the feasibility of obtaining LEXs that overexpress costimulatory molecules via genetically modified leukemia cells, thereby enhancing their anti-leukemia immunity and providing a potential therapeutic strategy that contributes to leukemia immunotherapy. [ABSTRACT FROM AUTHOR]

We consider an approximating control design for optimal mixing of a non-dissipative scalar field θ in an unsteady Stokes flow. The objective of our approach is to achieve optimal mixing at a given final time T > 0 , via the active control of the flow velocity v through boundary inputs. Due to zero diffusivity of the scalar field θ , establishing the well-posedness of its Gâteaux derivative requires sup t ∈ [ 0 , T ] ‖ ∇ θ ‖ L 2 < ∞ , which in turn demands the flow velocity field to satisfy the condition ∫ 0 T ‖ ∇ v ‖ L ∞ (Ω) d t < ∞ . This condition results in the need to penalize the time derivative of the boundary control in the cost functional. Consequently, the optimality system becomes difficult to solve (Hu in Appl Math Optim 78(1):201–217, 2018). Our current approximating approach provides a more transparent optimality system, with the set of admissible controls square integrable in space-time. This is achieved by first introducing a small diffusivity to the scalar equation and then establishing a rigorous analysis of convergence of the approximating control problem to the original one as the diffusivity approaches to zero. Uniqueness of the optimal solution is obtained for the two dimensional case. [ABSTRACT FROM AUTHOR]

Tire cornering characteristics have significant influence on vehicle lateral dynamics control. Unlike traditional tire mechanics models which are established based on the research experience or the mechanics mechanism, in this study, a novel experimental data-driven modeling approach is presented to model the tire cornering characteristics based on piecewise affine (PWA) identification method. In this approach, the highly nonlinear dynamic of the tire cornering characteristics is well approximated by several affine submodels acting on different regions. To obtain the experimental data which can accurately reflect the tire cornering characteristics, the tire tests are firstly carried out through a high-performance flat-plate test bench. On this basis, the PWA identification of the tire cornering characteristics is composed of the data clustering, the parameter estimation of the affine submodels and the calculation of the hyperplane coefficient matrices. The simulation results of the PWA identification model are finally compared with the experimental data to illustrate that the identified model has high accuracy in approximating the tire nonlinear cornering characteristics under wide range driving conditions. [ABSTRACT FROM AUTHOR]

The precise circuit of the substantia nigra pars reticulata (SNr) involved in temporal lobe epilepsy (TLE) is still unclear. Here we found that optogenetic or chemogenetic activation of SNr parvalbumin+ (PV) GABAergic neurons amplifies seizure activities in kindling- and kainic acid-induced TLE models, whereas selective inhibition of these neurons alleviates seizure activities. The severity of seizures is bidirectionally regulated by optogenetic manipulation of SNr PV fibers projecting to the parafascicular nucleus (PF). Electrophysiology combined with rabies virus-assisted circuit mapping shows that SNr PV neurons directly project to and functionally inhibit posterior PF GABAergic neurons. Activity of these neurons also regulates seizure activity. Collectively, our results reveal that a long-range SNr-PF disinhibitory circuit participates in regulating seizure in TLE and inactivation of this circuit can alleviate severity of epileptic seizures. These findings provide a better understanding of pathological changes from a circuit perspective and suggest a possibility to precisely control epilepsy. The neural circuits through which the substantia nigra pars reticulata (SNr) exerts its role in epilepsy control are not known. Here the authors reveal that a long-range SNr-parafascicular nucleus disinhibitory circuit participates in regulating seizures in temporal lobe epilepsy and inhibition of this circuit can alleviate severity of epileptic seizures. [ABSTRACT FROM AUTHOR]

We begin an investigation of hybridizable discontinuous Galerkin (HDG) methods for approximating the solution of Dirichlet boundary control problems governed by elliptic PDEs. These problems can involve atypical variational formulations, and often have solutions with low regularity on polyhedral domains. These issues can provide challenges for numerical methods and the associated numerical analysis. We propose an HDG method for a Dirichlet boundary control problem for the Poisson equation, and obtain optimal a priori error estimates for the control. Specifically, under certain assumptions, for a 2D convex polygonal domain we show the control converges at a superlinear rate. We present 2D and 3D numerical experiments to demonstrate our theoretical results. [ABSTRACT FROM AUTHOR]

The laser source with 3 μm/2 μm output wavelength has many application prospects in clinical medicine, photoelectric countermeasure, and scientific research measurement. An Er3+ doped ZBLAN fiber laser with output wavelength of 2 .8 μm and 1 .6 μm is experimentally studied. By setting the pump power to 5 W, a continuous dual-wavelength output with a central wavelength of 2.803 μm and 1.61 μm is obtained and the corresponding maximum output power is 362.4 mW and 108.6 mW. The slope efficiency is 12.1% and 4.94% respectively. What's more, the slope efficiency is 12.1% and 4.94% respectively, and the fluctuation rates of peak power of the two wavelengths are 9.7% and 2.1% within 4 h which indicate that the laser has relatively good stability. [ABSTRACT FROM AUTHOR]

The pulverization of Sn-based electrode materials, caused by the large volume effect during the charging/discharging process, seriously affects their battery life. Compounding electrospun carbon fibers with a porous structure is an effective means of solving this problem. In this work, porous carbon nanofibers (PCNFs) containing Sn and tin antimonide (SnSb) alloy nanoparticles are prepared by electrospinning using self-made highly dispersed Sb–SnO2 (denoted as antimony-doped tin oxide) wet gel as the precursor of Sn and Sb and polyacrylonitrile (PAN) and polyvinylpyrrolidone (PVP) as the carbon sources. The porous structure is constructed using the difference in solubility in water between PAN and PVP. The results indicate that the as-fabricated PCNFs have a large number of pore structures and an even distribution of Sn and SnSb alloy nanoparticles, which are conducive to an increase in the content of Sn–SnSb electrode active materials. The porous structure both increases the specific surface area of the electrode material and effectively alleviates volume change. Therefore, the as-fabricated Sn–SnSb/PCNFs exhibit high specific capacities and outstanding rate performance and cycling retention, delivering specific capacities of 922 mAh g−1 and 266 mAh g at 50 mA g−1 and 5 A g−1, respectively, as well as a high cycle stability (71%) for 600 cycles at 1 A g−1. This demonstrates their potential application as anode materials in high-energy-density lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Abstract: Surface-enhanced Raman scattering (SERS) has gained a reputation as one of the most sensitive spectroscopic methods for biosensing. However, to design a SERS-based biosensor, almost all currently used methods involve the time-consuming and complicated modification of the metallic nanoparticles, which restricts their wide spread applications. Herein, a facile and sensitive SERS-based aptasensor for colorimetric detection of acetamiprid (AC) was demonstrated. The prepared crystal violet (CV)-aptamer decorated gold nanoparticles (GNPs) tended to aggregate in a solution with high concentrations of salt, and displayed a purple color. In the presence of AC, the specific binding of the target with the aptamer generated conformation changes of aptamer (confirmed by the circular dichroism spectrum), which made the stable GNPs aggregation in the salt solution, thus resulting the SERS signal enhanced. Sequel, the SERS intensity was increased linearly with the concentration of AC ranging from 3.0 × 10−8 to 4.0 × 10−6 M, with a relatively low limit of 1.76 × 10−8 M. The detection ability of AC by this biosensor was also confirmed with different adulterated tea. This approach is not only straightforward in fabrication but also cost-effective in operation, and can be used for diverse bio-molecules detection by changing the aptamer.Graphical abstract: [ABSTRACT FROM AUTHOR]

Since Burkholderia thailandensis is included in the reference spectra of the VITEK MS libraries rather than Burkholderia pseudomallei, B. pseudomallei cannot be correctly identified in the current version of VITEK MS. This study was undertaken to evaluate the utility of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) with the VITEK MS plus system in the detection of B. pseudomallei and B. thailandensis isolates. For each species, we increased the reference spectra, and then, a SuperSpectrum was created based on the selection of 39 specific masses. In a second step, we validated the SuperSpectra with 106 isolates identified by 16S rRNA gene sequencing. The results showed that there was 100% agreement between the validation strains analyzed by MALDI-TOF MS and those evaluated using 16S rRNA gene sequencing analysis methods. Therefore, MALDI-TOF MS is a promising, rapid, and economical method to monitor the outbreaks and spread of B. pseudomallei and B. thailandensis isolates. [ABSTRACT FROM AUTHOR]

A method with double L-shaped array for direction-of-arrival (DOA) estimation in the presence of sensor gain-phase errors is presented. The reason for choosing double L-shaped array is that the shared elements between sub-arrays are the most and rotation invariant property can be applied for this array. The proposed method is introduced as follows. (1) If the number of signal is one, first the gain errors are estimated and removed with the diagonal of the covariance matrix of the array output. Then the array is rotated by an unknown angle and DOA can be estimated with the relationship between signal subspace and steering vector of signal. (2) If signals are more than one, the method for eliminating gain errors is the same with the previous case, and then the phase errors are removed by the Hadamard product of the (cross) covariance matrix and its conjugate. After the errors are eliminated, the DOAs can be estimated by rotation invariant property and orthogonal joint diagonalization for the Hadamard product. This method requires neither calibrated sources nor multidimensional parameter search, and its performance is independent of the phase errors. Simulation results demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

We consider a distributed optimal control problem governed by an elliptic convection diffusion PDE, and propose a hybridizable discontinuous Galerkin method to approximate the solution. We use polynomials of degree k+1 to approximate the state and dual state, and polynomials of degree k≥0 to approximate their fluxes. Moreover, we use polynomials of degree k to approximate the numerical traces of the state and dual state on the faces, which are the only globally coupled unknowns. We prove optimal a priori error estimates for all variables when k≥0. Furthermore, from the point of view of the number of degrees of freedom of the globally coupled unknowns, this method achieves superconvergence for the state, dual state, and control when k≥1. We illustrate our convergence results with numerical experiments. [ABSTRACT FROM AUTHOR]

We discuss the optimal boundary control problem for mixing an inhomogeneous distribution of a passive scalar field in an unsteady Stokes flow. The problem is motivated by mixing the fluids within a cavity or vessel at low Reynolds numbers by moving the walls or stirring at the boundary. It is natural to consider the velocity field which is induced by a control input tangentially acting on the boundary of the domain through the Navier slip boundary conditions. Our main objective is to design an optimal Navier slip boundary control that optimizes mixing at a given final time. This essentially leads to a finite time optimal control problem of a bilinear system. In the current work, we consider a general open bounded and connected domain Ω⊂Rd,d=2,3. We employ the Sobolev norm for the dual space (H1(Ω))′ of H1(Ω) to quantify mixing of the scalar field in terms of the property of weak convergence. A rigorous proof of the existence of an optimal control is presented and the first-order necessary conditions for optimality are derived. [ABSTRACT FROM AUTHOR]

The idea of aromatherapy, using essential oils, has been considered as an alternative antidepressant treatment. In the present study, we investigated the effect of Roman chamomile essential oil inhalation for two weeks on depressive-like behaviors in Wistar-Kyoto (WKY) rats. We found that inhalation of either Roman chamomile or one of its main components α-pinene, attenuated depressive-like behavior in WKY rats in the forced swim test. Using isobaric tags for relative and absolute quantitation analysis (iTRAQ), we found that inhalation of α-pinene increased expression of proteins that are involved in oxidative phosphorylation, such as cytochrome c oxidase subunit 6C-2, cytochrome c oxidase subunit 7A2, ATPase inhibitor in the hippocampus, and cytochrome c oxidase subunit 6C-2, ATP synthase subunit e, Acyl carrier protein, and Cytochrome b-c1 complex subunit 6 in the PFC (prefrontal cortex). In addition, using the quantitative real-time polymerase chain reaction technique, we confirmed an increase of parvalbumin mRNA expression in the hippocampus, which was shown to be upregulated by 2.8-fold in iTRAQ analysis, in α-pinene treated WKY rats. These findings collectively suggest the involvement of mitochondrial functions and parvalbumin-related signaling in the antidepressant effect of α-pinene inhalation. [ABSTRACT FROM AUTHOR]

This paper presents the high-diversity space division multiplexing (SDM) visible light communications (VLCs) utilizing a fisheye-lens-based imaging receiver. The receiver features ultra-wide field-of-view, good illumination uniformity, ultra-high imaging quality, and compact size; therefore, it can realize omnidirectional receiving and provide high spatial diversity for the SDM VLC system. In the presented system, four data streams are parallelly transmitted by commercial phosphorescent white light-emitting diodes, and discrete multitone signals based on quadrature amplitude modulation and bit loading are employed to achieve high spectral efficiency. The experiment verifies that the interchannel interference is effectively alleviated due to the high spatial diversity provided by the fisheye-lens-based receiver, and an aggregate data rate of 1.3 Gbit/s is achieved with the limited 3-dB bandwidth of 20 MHz. Besides, it is feasible to extend the system to more channels to achieve higher capacity. The experimental results indicate that the fisheye-lens-based imaging receiver is a potential candidate for high-speed VLC applications. [ABSTRACT FROM AUTHOR]

Existing collaborative optimization techniques with multiple coupled subsystems are predominantly focused on single-objective deterministic optimization. However, many engineering optimization problems have system and subsystems that can each be multi-objective, constrained and with uncertainty. The literature reports on a few deterministic Multi-objective Multi-Disciplinary Optimization (MMDO) techniques. However, these techniques in general require a large number of function calls and their computational cost can be exacerbated when uncertainty is present. In this paper, a new Approximation-Assisted Multi-objective collaborative Robust Optimization (New AA-McRO) under interval uncertainty is presented. This new AA-McRO approach uses a single-objective optimization problem to coordinate all system and subsystem multi-objective optimization problems in a Collaborative Optimization (CO) framework. The approach converts the consistency constraints of CO into penalty terms which are integrated into the system and subsystem objective functions. The new AA-McRO is able to explore the design space better and obtain optimum design solutions more efficiently. Also, the new AA-McRO obtains an estimate of Pareto optimum solutions for MMDO problems whose system-level objective and constraint functions are relatively insensitive (or robust) to input uncertainties. Another characteristic of the new AA-McRO is the use of online approximation for objective and constraint functions to perform system robustness evaluation and subsystem-level optimization. Based on the results obtained from a numerical and an engineering example, it is concluded that the new AA-McRO performs better than previously reported MMDO methods. [ABSTRACT FROM AUTHOR]

Suspension animal cell culture is now routinely scaled up to bioreactors on the order of 10,000 L, and greater, to meet commercial demand. However, the concern of the 'shear sensitivity' of animal cells still remains, not only within the bioreactor, but also in the downstream processing. As the productivities continue to increase, titer of ~10 g/L are now reported with cell densities greater than 2 × 10 cells/mL. Such high, and potentially higher cell densities will inevitably translate to increased demand in mass transfer and mixing. In addition, achieving productivity gains in both the upstream stage and downstream processes can subject the cells to aggressive environments such as those involving hydrodynamic stresses. The perception of 'shear sensitivity' has historically put an arbitrary upper limit on agitation and aeration in bioreactor operation; however, as cell densities and productivities continue to increase, mass transfer requirements can exceed those imposed by these arbitrary low limits. Therefore, a better understanding of how animal cells, used to produce therapeutic products, respond to hydrodynamic forces in both qualitative and quantitative ways will allow an experimentally based, higher, 'upper limit' to be created to guide the design and operation of future commercial, large scale bioreactors. With respect to downstream hydrodynamic conditions, situations have already been achieved in which practical limits with respect to hydrodynamic forces have been experienced. This review mainly focuses on publications from both the academy and industry regarding the effect of hydrodynamic forces on industrially relevant animal cells, and not on the actual scale-up of bioreactors. A summary of implications and remaining challenges will also be presented. [ABSTRACT FROM AUTHOR]

series of pyrochlore oxides, RRuO (R = Pr, Sm-Ho) were synthesized under mild hydrothermal conditions. All the samples crystallize in uniform octahedron characteristically. The products were characterized by powder X-ray diffraction, scanning electron microscopy, energy-disperse X-ray spectroscopy, and dc susceptibility, and the factors that affected the crystallization were discussed. It was found that the purity of products depends strongly on the raw materials and the amount of alkalinity in the initial reaction mixtures. The ZFC and FC susceptibilities of all of the compounds RRuO at low temperature were also measured and discussed. [ABSTRACT FROM AUTHOR]

Side populations of glioblastoma cells are resistant to chemotherapy basically due to ABCG2-mediated efflux of small-molecule drugs. The herpes simplex virus thymidine kinase/ganciclovir suicide gene therapy system is one of the best-characterized strategies for malignant tumors including glioblastoma. Since this system involves a small-molecule drug ganciclovir, we wonder if glioblastoma side population cells are able to “pump out” ganciclovir and thus resistant to this suicide gene therapy. By 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium assay, we found that side populations are more resistant to this system than non-side populations. By flow cytometry and competition assay, we found that ganciclovir is a substrate for ABCG2. [ABSTRACT FROM AUTHOR]

The cancer stem cell (CSC) hypothesis has provided insights into the initiation and recurrence of brain tumor. Specific identification and targeted elimination of these CSCs within the tumor mass represents a promising therapeutic strategy for refractory brain tumors. In this study, we attempted to identify CSCs in the rat C6 glioma cell line by three different identification methods. It is interesting to note that single-cell clonal analysis showed most C6 cells are cancer stem-like cells with characteristics of self-renewal, multilineage differentiation potentials in vitro, and tumorigenic capacity in vivo. It is surprising to note that CD133 failed to identify the total cancer stem-like cell population in the C6 line, since both CD133 (+) and CD133 (−) C6 cells have cancer stem-like cell fractions. Moreover, Hoechst 33342 staining, which is used in flow cytometry to isolate the side population (SP), was found to be harmful to C6 cells. Therefore, CD133 (−) and non-SP C6 cells may also harbor cancer stem-like cells. These results imply the limitation of using current identification methods in C6 line and underscore the importance of defining the genetic and molecular basis of CSCs. [ABSTRACT FROM AUTHOR]

Motion estimation is an important part of H.264/AVC encoding progress, with high computational complexity. Therefore, it is quite necessary to find a fast motion estimation algorithm for real-time applications. The algorithm proposed in this letter adjudges the macroblocks activity degree first; then classifies different video sequences, and applies different search strategies according to the result. Experiments show that this method obtains almost the same video quality with the Full Search (FS) algorithm but with reduced more than 95% computation cost. [ABSTRACT FROM AUTHOR]

The exponential stability of a multi-state device is discussed in this paper. We present that the C 0-semigroup generated by the system operator is quasi-compact and irreducible. It is known that 0 is a simple eigenvalue of the system operator. In combination with this, we obtain that the time-dependent solution exponentially converges to the steady-state solution, which is the positive eigenfuction corresponding to the simple eigenvalue 0. [ABSTRACT FROM AUTHOR]

The network assignment image not only has a sharpness problem in the system audit but also the image angle deviates from the normal angle. Based on this, this study is based on image processing technology, using wavelet transform as the basic algorithm to process the image images collected by the network education system. At the same time, this study extracts the image content by wavelet transform in image edge recognition and enhances the image to enhance the image clarity. For the problem of image tilt, this study proposes a method of detecting the edge of the image with wavelet transform and then performing image tilt correction with Hough transform. In addition, this study compared the performance of the image correction method of this research and the traditional image method through experimental verification. Through comparative analysis, we can know that the performance of this research algorithm is better, and it can provide theoretical reference for subsequent related research. [ABSTRACT FROM AUTHOR]