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Nonlinear optical rectification (NOR) coefficients in symmetric double-graded quantum wells with different geometrical configurations under non-resonant laser field in the presence of electric and magnetic fields are theoretically investigated. The quantum states under the applied external fields are obtained under effective mass approximation and using diagonalization method. Our calculated results indicate that the above-mentioned external fields play a significant role in manipulating the resonant peak values and peak positions of nonlinear optical rectification coefficients of the quantum system dynamically. Considerable NOR coefficient can be achieved, not only by choosing appropriate laser dressing parameter as well as the electric and magnetic fields, but also by choosing appropriate well and barrier widths. Our results show great advantages in dynamically tuning NOR coefficient of symmetric double-graded quantum wells using multi-physic fields, paving the way for possible application for tunable infrared detector and signal processing based on symmetric double-graded quantum wells. [ABSTRACT FROM AUTHOR]

The development of novel polymer dielectrics with enhanced dielectric performance is a great challenge for application of film capacitors in modern electronics and electrical systems. Herein, an innovative approach of chemical vapor deposition polymerization technology is proposed to prepare the all‐organic sandwich structured parylene/polyimide/parylene (Py/PI/Py) composite films by employing poly(chloro‐para‐xylylene) (parylene C) as the outer layers and polyimide (PI) as the inner layer. The Py/PI/Py composites exhibit superior thermal resistance and outstanding mechanical properties. Moreover, thanks to the interfacial effect which contributes to reinforcing the dielectric response and the thickness effect which facilitates improving the breakdown strength, the dielectric performance of Py/PI/Py composites has been enhanced significantly. Accordingly, dielectric constant of 4.52–5.09, dissipation factor of 0.21–1.01%, and breakdown strength of 307–460 MV m−1 are achieved. Besides, notable energy storage performance is also obtained in Py/PI/Py composite dielectrics. Consequently, this novel application of chemical vapor deposition polymerization method in preparing all‐organic multilayered polymer composite films with sandwich structure shows promising potential in film capacitor applications in harsh conditions. [ABSTRACT FROM AUTHOR]

Objectives: Mesoderm, derived from a new layer between epiblast and hypoblast during gastrulation, can differentiate into various tissues, including muscles, bones, kidneys, blood, and the urogenital system. However, systematic elucidation of mesoderm characteristics and specific markers remains a challenge. This study aims to screen and identify candidate genes important for mesoderm development. Materials and Methods: Cells originating from the three germ layers were obtained by laser capture microdissection, followed by microcellular RNA sequencing. Mesoderm‐specific differentially expressed genes (DEGs) were identified by using a combination of three bioinformatics pipelines. Candidate mesoderm‐specific genes expression were verified by real‐time quantitative polymerase chain reaction analysis and immunohistochemistry. Functional analyses were verified by ESCs‐EBs differentiation and colony‐forming units (CFUs) assay. Results: A total of 1962 differentially expressed mesoderm genes were found, out of which 50 were candidate mesoderm‐specific DEGs which mainly participate in somite development, formation of the primary germ layer, segmentation, mesoderm development, and pattern specification process by GO analysis. Representative genes Cdh2, Cdh11, Jag1, T, Fn‐1, and Pcdh7 were specifically expressed in mesoderm among the three germ layers. Pcdh7 as membrane‐associated gene has hematopoietic‐relevant functions identified by ESCs‐EBs differentiation and CFUs assay. Conclusions: Spatial transcriptomic profiling with multi‐method analysis and confirmation revealed candidate mesoderm progenitors. This approach appears to be efficient and reliable and can be extended to screen and validate candidate genes in various cellular systems. [ABSTRACT FROM AUTHOR]

Faster-than-Nyquist signaling (FTNS) has already been shown to increase the communication capacity on certain channels such as additive white Gaussian noise and block flat multiple-input multiple-output (MIMO) Rayleigh fading channels. The following issues, however, remain unresolved: 1) whether FTNS enables a capacity increase in generalized MIMO Rayleigh fading channels that are selective in time, frequency, and space; and 2) how channel selectivities affect the capacity and if present, the FTN capacity gain. To address the issues, this paper firstly investigates the ergodic capacity of MIMO-FTN transmission over triply-selective fading channels. We derive a low-complexity approximate capacity formula and also show how it degenerates in other channel models, such as doubly-selective single-input single-output fading channels, which can be considered as the special cases of triply-selective fading channels. The capacity evaluation results obtained under different channel conditions show that: 1) MIMO-FTN outperforms MIMO-Nyquist in terms of capacity; 2) the FTN gains are nearly consistent, while the FTN gains obtained in the frequency-selective fading channels are slightly higher than those obtained in the flat fading channels. [ABSTRACT FROM AUTHOR]

Parametric interpolation has been widely used in robot control because of its advantages over traditional linear or circular interpolation. The NURBS interpolation based on S-shaped feedrate scheduling can realize the smooth continuous motion of robots, but it also faces two challenges. One challenge is that when the NURBS curve is split into multiple blocks, if one or more blocks are too short, the final feedrate profile is often discontinuous. The other challenge is that the NURBS curve cannot be obtained entirely due to calculation errors. In this paper, a high-precision NURBS interpolator based on S-shaped feedrate scheduling is proposed. In this interpolator, a bidirectional velocity scanning scheme is developed to effectively handle the too short split blocks of the NURBS curve. Meanwhile, an optimization algorithm is proposed to ensure the precision of NURBS curves. The feasibility and advantages of the proposed method are verified through case studies. [ABSTRACT FROM AUTHOR]

Adiponectin (APN) is reported to be correlated closely with autonomic nervous function in different clinical settings. Heart rate recovery (HRR) is a noninvasive and readily obtainable indicator, which reflects the coordinated interplay between parasympathetic reactivation and sympathetic withdrawal. This study aimed to investigate the relationship between serum APN and HRR in polycystic ovarian syndrome (PCOS) women. Eighty-nine PCOS women were enrolled and divided into two groups. Women with HRR values slower than 12 beats were defined as Blunted HRR Group. APN levels were compared between Blunted HRR Group and Normal HRR Group. Multivariate logistic regression analysis and multiple linear regression analysis were performed to determine which clinical variables were independently associated with HRR and APN levels, respectively. Twenty-three women were categorized into Blunted HRR Group, in which APN level was significantly lower than Normal HRR Group. Age, body mass index, hypertension, and APN were independent factors of attenuated HRR in PCOS women. Meanwhile, multiple linear regression analysis showed age, dyslipidemia, and homeostasis model assessment-insulin resistance (HOMA-IR) were closely associated with APN levels in PCOS women. Our findings suggested that decreased APN concentration was closely associated with HRR blunt in PCOS women. Further studies are needed to explore the underlying interactions between APN and autonomic nervous function. [ABSTRACT FROM AUTHOR]

In this paper, we introduce a novel point-to-surface representation for 3D point cloud learning. Unlike the previous methods that mainly adopt voxel, mesh, or point coordinates, we propose to tackle this problem from a new perspective: learn a set of quadratic terms based static and global reference surfaces to describe 3D shapes, such that the coordinates of a 3D point (x, y, z) can be extended to quadratic terms (xy, xz, yz, $\ldots $) and transformed to the relationship between the local point and the global reference surfaces. Then, the static surfaces are changed into dynamic surfaces by adaptive contribution weighting to improve the descriptive capability. Towards this end, we propose our point-to-surface representation, a new representation for 3D point cloud learning that has not been attempted before, which can assemble local and global geometric information effectively by building connections between the point cloud and the learned reference surfaces. Given 3D points, we show how the reference surfaces are constructed, and how they are inserted into the 3D learning pipeline for different tasks. The experimental results confirm the effectiveness of our new representation, which has outperformed the state-of-the-art methods on the tasks of 3D classification and segmentation. [ABSTRACT FROM AUTHOR]

Faster-than-Nyquist signaling (FTNS) has emerged as a promising technique to increase communication capacity in bandwidth-limited channels. However, the presence of FTN-induced inter-symbol interference (FTN-ISI) in the received observations, is detrimental to channel estimation (CE) and data detection in terms of computational complexity and performance. This paper copes with these problems by incorporating linear pre-equalization (LPE) and composite precoding formed by linear spectral precoding and Tomlinson-Harashima precoding (THP), into the FTNS. Specifically, LPE completely pre-equalizes the FTN-ISI, while spectral precoding resolves the LPE-caused signal spectral broadening by introducing proper artificial ISI, which is pre-equalized by THP. Channel-induced ISI, as the only ISI component in the observations, is estimated and equalized using the classical frequency-domain low-complexity schemes. We show that there are four advantages of the LPE-aided CE over the CE designed for the FTN transmissions without FTN-ISI pre-equalization, namely lower pilot overhead, simpler yet optimal pilot sequence design, lower mean-squared error of CE, and more robust against the FTN-ISI. Simulation results show that our scheme improves the performance of CE and detection, compared to existing FTN frequency-domain CE and equalization schemes. [ABSTRACT FROM AUTHOR]

The assembly operations for robots in unstructured environments face tasks with generalized geometric information. The most essential issue for geometry perception is to estimate the relative pose between mating parts and then plan the corresponding actions. Current perception methods mainly focus on template matching of specific parts, which is still lacking in geometric generalization. To enhance the perception generalization ability, we propose an operation framework combining geometry perception and motion planning for robotic assembly manipulation. Semantic segmentation embodies a strong generalization capacity in image processing, which we utilized to extract the geometric features of assembly parts. The networks are trained via a self-made peg-hole image dataset. To reduce the measurement noise, the virtual point clouds for the peg and hole section are reconstructed with semantic mask and camera image principle, and a uniformization algorithm is adopted to raise the quality of the point clouds. The registration is utilized with the noise-free, uniform virtual point clouds, and the relative pose between two mating parts can be estimated more precisely. Also, the sequence of interactive geometry perception actions is defined. The performance of our framework is validated on assembly experiments, including different geometries in and out of our dataset. The results show that the framework proposed in this paper can perceive the generalization of geometry features for assembly parts, and leads to intelligent robotic assembly. [ABSTRACT FROM AUTHOR]

• FRN layer can improve performance and reduce the dependence on batch size. • ECA DGCNN can enhance the feature learning ability of the model on the graph structure data. • FEPoinTr achieves superior performance on multiple data sets. • The performance loss of FEPoinTr in small batches is significantly less than that of other models. The point cloud data generated by LiDAR sensors has rich spatial geometry information, which is crucial for many fields. However, due to the limitations of the sensor, the point cloud with incomplete geometric information is usually obtained. To solve this problem, we propose FEPoinTr, which improves performance and reduces batch size dependency by introducing an FRN layer to normalize. In addition, the ECA DGCNN network is used to enhance the feature learning ability of the model on the graph structure data. We verified the advantages of FEPoinTr on ShapeNet-55, PCN, and KITTI datasets, achieving 0.90CD on ShapeNet-55, 7.52CD on PCN, and 0.504MMD on real point cloud dataset KITTI. Both index results and visualization results are better than other models. It is worth noting that when the batch size is reduced to 1, the CD index on the ShapeNet-55 is 1.13, the F-Score index is 0.503, and the performance loss at small batches is significantly less than that of other models. [ABSTRACT FROM AUTHOR]

Engineering transporter for improved efflux efficiency provides a powerful strategy to alleviate product-associated cytotoxicity and promote microbial production of desired compounds. However, the scarcity of efficient transporters limits its application in the construction of microbial cell factories. Here, we sought to improve the transport performance of the EamB transporter, a L-cysteine exporter from Escherichia coli. A total of four EamB variants (A31V, I83M, G156A, and N157M) were firstly obtained by random mutagenesis and screening, and two other improved mutant (G156S and N157S) were also identified by site-specific saturation mutagenesis. The transport assays revealed that the G156S and N157S mutants had increased L-cysteine export capacity relative to the native EamB transporter. A combinatorial mutagenesis approach was used to generate the best mutant G156S/N157S, which conferred cells optimal resistance to L-cysteine and highest yields of L-cysteine in shake flask fermentation. Taken together, our results offer several EamB mutants with improved efflux properties, highlighting the potential of these exporters in L-cysteine fermentative production. [ABSTRACT FROM AUTHOR]

Motivation Integrative multi-feature fusion analysis on biomedical data has gained much attention recently. In breast cancer, existing studies have demonstrated that combining genomic mRNA data and DNA methylation data can better stratify cancer patients with distinct prognosis than using single signature. However, those existing methods are simply combining these gene features in series and have ignored the correlations between separate omics dimensions over time. Results In the present study, we propose an adaptive multi-task learning method, which combines the Cox loss task with the ordinal loss task, for survival prediction of breast cancer patients using multi-modal learning instead of performing survival analysis on each feature dataset. First, we use local maximum quasi-clique merging (lmQCM) algorithm to reduce the mRNA and methylation feature dimensions and extract cluster eigengenes respectively. Then, we add an auxiliary ordinal loss to the original Cox model to improve the ability to optimize the learning process in training and regularization. The auxiliary loss helps to reduce the vanishing gradient problem for earlier layers and helps to decrease the loss of the primary task. Meanwhile, we use an adaptive weights approach to multi-task learning which weighs multiple loss functions by considering the homoscedastic uncertainty of each task. Finally, we build an ordinal cox hazards model for survival analysis and use long short-term memory (LSTM) method to predict patients' survival risk. We use the cross-validation method and the concordance index (C-index) for assessing the prediction effect. Stringent cross-verification testing processes for the benchmark dataset and two additional datasets demonstrate that the developed approach is effective, achieving very competitive performance with existing approaches. Availability and implementation https://github.com/bhioswego/ML_ordCOX. [ABSTRACT FROM AUTHOR]

Chronic inflammatory diseases of the respiratory tract, such as chronic obstructive pulmonary disease (COPD) and asthma, are severe lung diseases that require effective treatments. In search for new medicines for these diseases, there is an unmet need for predictive and translatable disease-relevant in vitro/ex vivo models to determine the safety and efficacy of novel drug candidates. Here, we report the use of precision cut lung slices (PCLS) as a potential ex vivo platform to study compound effects in a physiologically relevant environment. PCLS derived from an elastase-challenged mouse model display key characteristics of increased inflammation ex vivo, which is exacerbated further upon challenge with LPS, mimicking the immune insult of a pathogen triggering disease exacerbation. Such LPS-induced inflammatory conditions are significantly abrogated by immunomodulatory agents targeting specific inflammatory signaling pathways in the absence of cytotoxic effects in lung slices. Thus, an ex vivo model of PCLS with a simulated pathogenic insult can replicate proposed in vivo pharmacological effects and thus could potentially act as a valuable tool to investigate the underlying mechanisms associated with lung safety, therapeutic efficacy and exacerbations with infection. [ABSTRACT FROM AUTHOR]

Over-the-air (OTA) measurement is mandatory for 5G mm-wave wireless devices. The compact antenna test range (CATR) is the baseline method in the current version of TR 38.810 in 3rd generation partnership project (3GPP) and cellular telecommunications industry association (CTIA) millimeter-wave (mm-Wave) test plan. For CATR, both amplitude and phase variations inside the quiet zone (QZ) could affect the final OTA results significantly and hence need to be characterized carefully. Especially in the phase validation of QZ, even slight misalignments between sampling plane and incident plane wavefront due to the limited precision of the positioner or tolerance in antenna fixture could result in large phase variations, which is not the true phase property of QZ. This letter presents a method to remove the effect of the angular error due to misalignment when measuring the phase variation inside QZ. By adopting the proposed method to the measured phase data, any angular error due to misalignment with respect to the incident plane wavefront will be eliminated mathematically, leaving the true phase variations of QZ only. In the meanwhile, the proposed method can alleviate the requirements of fixture manufacture and alignment precision and reduce the test cost. [ABSTRACT FROM AUTHOR]

Orthogonal time frequency space (OTFS) has shown to be a promising modulation technology that achieves the robust wireless transmission in high-mobility environments. The high mobility incurred Doppler effect in OTFS system, is represented as a continuous and relatively large band in the Doppler frequency. It yields the equivalent channel responses (ECRs) in the system change significantly within one symbol block, posing a challenge to channel estimation (CE) or tracking. In order to tackle this issue, in this paper, a set of transform-domain basis functions is designed to span a low-dimensional subspace for modeling the OTFS channel. Then, the CE can be performed by estimating a few projection coefficients of ECRs in the developed subspace, with training pilots. According to the individual transmission characteristic of OTFS signal, we propose a corner-inserted pilot pattern, which targets the low pilot overhead and satisfactory CE performance. Moreover, an OTFS signal detector, leveraging the time-domain channel equalization, linear-complexity interference cancellation and delay-Doppler domain maximal ratio combining detection, is developed to retrieve the transmitted data symbols. The simulations show the precisely estimated ECRs enable the detector to ideally demodulate 256-ary quadrature amplitude modulation signaling, under a velocity of 550 km/h at 5.9 GHz carrier frequency. [ABSTRACT FROM AUTHOR]

Orthogonal time frequency space (OTFS) is a two-dimensional modulation scheme realized in the delay-Doppler domain, which targets the robust wireless transmissions in high-mobility environments. In such scenarios, OTFS signal suffers from multipath channel with continuous Doppler spread, which results in significant inter-symbol interference and inter-Doppler interference (IDI). In this article, we analyze the interference generation mechanism, and compare statistical distributions of the IDI in two typical cases, i.e., limited-Doppler-shift channel and continuous-Doppler-spread channel (CoDSC). Focusing on the OTFS signal transmission over the CoDSC, our study firstly indicates that the widespread IDI incurs a computational burden for the element-wise detector like the message passing in the state-of-the-art works. Addressing this challenge, we propose a block-wise OTFS receiver by exploiting the structure and characteristics of the OTFS transmission matrix. In the receiver, we deliberately design an iteration strategy among the least squares minimum residual based channel equalizer, reliability-based symbol detector and interference eliminator, which can realize fast convergence by leveraging the sparsity of channel matrix. The simulations demonstrate that, in the CoDSC, the proposed scheme achieves much less detection error, and meanwhile reduces the computational complexity by an order of magnitude, compared with the state-of-the-art OTFS receivers. [ABSTRACT FROM AUTHOR]

• Constructed a groundwater numerical model by Visual MODFLOW and studized the feasibility of mine water recharge to aquifers. • Analyzed the impact of mine water recharge on the water level and inflow of aquifers. • To ensure the safe mining in the future, the dynamic water inflow under different mining levels was predicted. Water inflow poses a critical safety concern in coal mining. The pressing challenge in current mine water inflow research is the need to enhance the prediction of dynamic changes in mine water inflow across different mining stages. In this study, the hydrogeological conditions and aquifer structural characteristics of the Wutongzhuang Coal Mine in Hebei Province, China were analyzed, and the results were combined with pumping test and drilling data. A numerical model of groundwater flow in the study area was established using Visual MODFLOW and the model was calibrated and verified by comparing its results with the measured values to ensure that it realistically reflected the state of groundwater movement in the study area. The results of numerical simulation indicated that: (1) The water level of the Ordovician aquifer varies significantly by season. A large exposed area of Ordovician limestone in the western mountainous region receives a large amount of rainfall infiltration recharge in the summer rainy period that raises the water level of the Ordovician aquifer in the study area. (2) The groundwater system in the study area is in an equilibrium state, with the water inflow approximately equal to the outflow. (3) The recharge of mine drainage water has a slight positive effect on the Ordovician water level and the floor water inflow, with the impact on the water level of the aquifer decreasing as the distance from the recharge well and the import of Ordovician limestone water increase. In cases in which there is mine water recharge, the water level of the Ordovician aquifer is approximately 0.33 to 1.37 m higher than in cases without recharge, resulting in an increase in water inflow of approximately 10.6 m3/d. (4) In cases in which there is recharge of all drainage water, the maximum water inflow into the fifth mining area is 3,491.3 m3/d, which is 12.5 m3/d higher than in the case without recharge. These results provide important technical references for the formulation of mining schemes and water prevention measures in mining areas. [ABSTRACT FROM AUTHOR]

Faster-than-Nyquist signaling (FTNS) is capable of improving the spectral efficiency (SE) of communication systems. However, for conventional single-carrier FTNS (SC-FTNS) in which only symbol interval is reduced, the increase of SE is very limited due to the presence of inter-symbol interference (ISI) introduced by the FTNS. To deal with this problem, this paper proposes a new time-frequency compressed SC-FTNS (TFC-SC-FTNS) scheme that includes the conventional FTNS as a special case, to improve the SE via two dimensions simultaneously: time dimension by stacking symbols closer; frequency dimension by precoding to make the FTN signal spectrum more compact. Further, an optimization subject to a spectral mask constraint is performed on the precoder to suppress the ISI, according to a mean-square-error criterion, but the optimization problem is non-convex. A nontrivial contribution in the new scheme is that the non-convex problem is transformed into a convex one by a change of variable and an addition of admissibility constraint. Simulation results demonstrate that the proposed scheme significantly outperforms the conventional FTNS in terms of achievable SE or, equivalently, reception performance at a given SE. Further, with larger constellations applied, the gains of the TFC-FTNS increase. [ABSTRACT FROM AUTHOR]

Similar to orthogonal frequency division multiplexing receiver, the frequency-domain (FD) channel estimation (CE) and equalization are indispensable parts in the coherent single carrier frequency division multiplexing (SC-FDM) receiver. When the channel varies slowly, the FD processing is cost effective. For the applications with high mobility, the traditional implementation of the SC-FDM receiver causes significant performance degradation. In this paper, we propose to estimate time-varying pieces of channel taps for pilot symbols based on basis expansion model (BEM), and subsequently to reconstruct time-domain (TD) channel response for data symbols by utilizing the Slepian sequences-based piece-wise interpolation. Furthermore, two simplified schemes, i.e., the Slepian sequences-based multiple-point interpolation and the segmented BEM, are developed to reduce the computational complexity of the TD-CE. The Cramer-Rao lower bound (CRLB) of channel impulse response (CIR) estimation is also analyzed. In the light of the sparsity of TD channel gain matrix, we design an iterative least-squares QR decomposition algorithm to equalize the SC-FDM symbols. In the simulated SC-FDM system, when considering the carrier frequency of 5.9 GHz and the velocity of about 510 km/h, we observe that the traditional FD methods cause the demodulation failure, while the proposed TD processing schemes achieve ideal error-probability performance and preserve a relatively low complexity. [ABSTRACT FROM AUTHOR]

Renal clear cell carcinoma (RCC) is the most common pathological type of renal carcinoma and drug resistance often occurs. We studied the effect of hsa_circ_0035483 on gemcitabine sensitivity in RCC, and explored its regulatory effect on downstream hsa-miR-335 and Cyclin B1 (CCNB1). High-throughput sequencing was used to analyze the differentially expressed circRNA in RCC. The expressions of hsa_circ_0035483, hsa-miR-335, CCNB1, and autophagy-related proteins were detected by RT-PCR or Western blot. The target relationships were revealed by RNA pulldown assay and dual luciferase report assay. Autophagy marker LC3 was detected by immunofluorescence. Cell viability was detected by MTT assay. Hsa_circ_0035483 can facilitate gemcitabine-induced autophagy, and enhance the resistance of RCC to gemcitabine. Hsa-miR-335 is the target regulatory point of hsa_circ_0035483. In addition, hsa_circ_0035483 promotes autophagy and tumor growth and enhances gemcitabine resistance in RCC by regulating hsa-miR-335/CCNB1, and silenced hsa_circ_0035483 can enhance gemcitabine sensitivity in vivo. Hsa_circ_0035483 may be the target of gemcitabine resistance in the treatment of RCC. • We take the lead in studying the role of CCNB1 in gemcitabine-resistant RCC. • We found that CCNB1 and hsa_circ_0035483 are highly expressed in TK10 and UO31 cells. • Hsa_circ_0035483 can facilitate gemcitabine-induced autophagy, and enhance the resistance of RCC to gemcitabine. • Hsa_circ_0035483 may be the target of gemcitabine resistance in the treatment of RCC. [ABSTRACT FROM AUTHOR]

Abstract The water and nitrogen recovery from human urine are the crucial issues for the water recycling in the bioregenerative life support system (BLSS). Most of the water in the urine could be recovered through physical/chemical methods, however the efficiency of recovering nitrogen remained unsatisfactory. In our previous work, immobilized urease catalysis followed by reduced pressure distillation has been utilized to purify the urine, and high recovery efficiency of both water and nitrogen has been gained. However, the source of the urease and the immobilization preparation method would limit its practical application. In this study, biological activated carbon (BAC) immobilizing urease-producing microorganisms was explored as the continuous provider of urease to hydrolyze urea existing in human urine. The batch experiment results illustrated that it is feasible to use BAC technology to hydrolyze urea in urine and the highest urea hydrolysis efficiency of 79.33% was gained in synthetic urine with the powder activated carbon dosage (PACD) of 100 g/L and the hydraulic retention time (HRT) of 5 d. Image results of scanning electron microscope and confocal laser scanning microscope presented that BAC succcessfully immobilized living bacteria, and 16S rRNA high throughput sequencing illustrated that the main urease-producing bacteria were genera of Bacillus , Sporosarcina , Pseudomonas and Paracoccus , and genera of Pseudomonas and Paracoccus possessed heterotrophic nitrification ability as well. A pilot-scale membrane biological reactor inoculated with urea-hydrolyzing BAC cultivated in batch experiment was applied to treat the crew's urine continuously inside an experimental facility for BLSS, and the urea hydrolysis efficiency could maintain at 99.84% during 203 d operation. Graphical abstract Image 1 Highlights • Urease-producing bacteria immobilized on BAC were used to hydrolyze urea in urine. • 79.33% of the urea in synthetic urine was hydrolyzed by BAC in optimal conditions. • Living urease-producing bacteria were confirmed to be enriched by BAC. • Membrane-BAC reactor was successfully applied to treat crew's urine in BLSS. [ABSTRACT FROM AUTHOR]

Abstract With the size of metal nanostructures entering into the nanoscale region, electron surface scattering and quantum finite-size effect gradually dominate the physical properties of surface plasmon resonances. In this context, we investigate both the quantum corrected dielectric functions and the absorption spectra of thin gold films for different thickness by excluding and including electron surface scattering. Our results show that when don't taking into account electron surface scattering, the multiple peaks appear for both the quantum-corrected dielectric functions and the absorption spectra of thin gold films, which features the discretization of electronic states in small quantum-sized system. When including electron surface scattering, however, the multipeak structures are masked and even disappear due to a large broadening of themselves. The transition from the quantum results to the classical ones for increasing thickness is also clearly demonstrated for the two cases. Although we only discuss the dielectric function and optical absorption of gold films with quantum sizes, the phenomena are expected to be exhibited in other metal nanostructures. Our findings enrich our understanding of both electron surface scattering and quantum finite-size effect in small metal nanostructures, and pave the way for the designs of quantum plasmonic devices. Highlights • The discretization of electronic states in thin gold film is revealed. • Surface scattering on dielectric and optical properties in gold film is exhibited. • The transition from the quantum cases to the classical ones is exhibited. [ABSTRACT FROM AUTHOR]

The sintering behavior, microstructure and microwave dielectric properties of Li2(1+x)Mg3SnO6 ceramics were investigated in order to prepare dense phase-pure ceramics samples. The phase structures, density variation and pore morphology were especially correlated with the subsequent microwave dielectric properties. The experimental results showed that single phase rock-salt structure Li2Mg3SnO6 ceramics were obtained for x = 0.08. The actual sample density and microstructure (grain and pores) strongly depended on Li content x. The increasing in εr and Q×f values may be caused by increasing bulk density, reducing porosity as well as increasing grain boundaries. Well-densified Li2.16Mg3SnO6 ceramics were obtained with excellent microwave dielectric properties of εr = 11.4, Q×f = 140660 GHz and τf = -40.5 ppm/°C at 1360 °C. [ABSTRACT FROM AUTHOR]

The performance of high-speed and high-precision machine tool spindle is quite sensitive to the variation of system parameters. How to accurately predict the influences of key parameters on spindle characteristics is important for designers to achieve required machining accuracy. In the assembly of spindle system, the interference fit, which is always used to connect bearing and shaft, affects the performances of spindle system directly. Therefore, the quantitative investigation on the effects of interference fit on spindle characteristics are of great practical significance. In this paper, the effect mechanism of interference fit on spindle bearing system is explored and used to modify the analytical spindle bearing model. Firstly, the internal geometric relationships among the assembly bearing parts and shaft is analyzed under the influence of assembly deformation and centrifugal expansion. Then, the static and dynamic characteristics of spindle bearing system, including the bearing stiffness, maximum loosing speed, spindle stiffness as well as modal characteristics, are predicted under different interference fit values based on the modified spindle bearing model. The results show that the interference fit will stiffen the bearing and spindle system and result in obvious increments on bearing stiffness, spindle stiffness as well as the natural frequencies. A specially designed spindle test rig is built to verify the simulation results, and the variation of spindle stiffness and natural frequencies are measured under different interference fit values. The maximum error of the system natural frequencies between the analytical results and the experimental data is 7.36%, which confirmed the accuracy of the proposed analytical model. [ABSTRACT FROM AUTHOR]

Nonlinear optical rectification in symmetric coupled Al x Ga 1−x As/GaAs quantum wells with external electric field is investigated using numerical method and compact density matrix approach. Our results reveal that for the resonant peaks of optical rectification, a blue shift is exhibited for increasing electric field, while a red shift followed by a blue shift is exhibited for increasing barrier or well widths. The resonant peak values of optical rectification can reach a maximum value by an appropriate choice for the electric field, the barrier or well widths. Our studies pave the way for the design, optimization and applications of quantum-sized nonlinear optoelectronic devices. [ABSTRACT FROM AUTHOR]

The present study aimed to identify differentially expressed genes (DEGs) and biological processes (BPs) associated with asthma. DEGs between allergic asthma and healthy controls were screened from GSE15823. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses were performed using Database for Annotation, Visualization and Integrated Discovery. A protein-protein interaction network was constructed, followed by module mining and functional analysis. Additionally, GSE41649 was downloaded to validate the reliability of the results. In GSE41649, DEGs were identified and compared with key DEGs identified in GSE15823. A total of 43 upregulated and 275 downregulated DEGs were obtained from GSE15823. Upregulated DEGs, such as nitric oxide synthase 2 (NOS2), were enriched in BPs related to oxidation reduction. Downregulated DEGs, such as chemokine (C-C motif) ligand 19 (CCL21) and Cys-X-Cys ligand (CXCL9), were enriched in immune response-related BPs. Protein tyrosine phosphatase receptor type C (PTPRC), CCL21, and CXCL9 were identified as hub genes. The DEGs in module 1 were significantly involved in the chemokine signaling pathway (P<0.05). The expression of the key genes obtained in GSE15823 demonstrated the same variation directions in the two datasets. The immune response, oxidants and nitric oxide metabolic pathways may have important roles in the progression of asthma. DEGs of PTPRC, CCL21, CXCL9 and NOS2 may be the potential targets for asthma diagnosis and treatment. [ABSTRACT FROM AUTHOR]

Pregnancy-induced hypertension (PIH) remains the main cause of maternal and fatal mortality. Insulin resistance (IR) and autonomic nervous system (ANS) imbalance are two principal drivers of PIH development. Few previous researches investigated the association between IR and ANS imbalance in Chinese PIH patients. 120 pregnant women were enrolled in our study, sixty healthy pregnant women (control group), fourty one gestational hypertension (GH group) and nineteen preeclampsia patients (PE group). The homeostasis model assessment of IR (HOMA-IR) and markers of ANS (plasma biomarkers and heart rate variability (HRV) components) were collected. Body mass index (BMI), Ln(HOMA-IR), noradrenaline level, LnTP (total power), Ln SDNN (standard deviation of the normal-to-normal interval), LnLF (low frequency), LnLF/LnHF (low frequency/high frequency) were different in the GH and PE groups compared with the controls. Significant correlations were observed between Ln (HOMA-IR) and gestational duration (r = 0.237, P = 0.031), BMI（r = 0.314, P = 0.002), systolic blood pressure (r = 0.108, P = 0.016), noradrenaline (r = 0.451, P = 0.009), LnTP (r = −0.269, P = 0.015) and LnLF/HF (r = 0.183, P = 0.026) in those PIH patients. Furthermore, BMI, noradrenaline and LnTP were independent determinants of Ln(HOMA-IR) in PIH patients by multiple regression analysis. Our finding verified both IR and ANS imbalance were more severe in PIH patients than healthy pregnant women. Moreover, IR had a close association with ANS parameters in PIH patients, suggesting that they probably had contributory effects on the occurrence and development of PIH. We propose that these parameters could be added to the traditional indexes for individualized treatment of PIH patients in the future. [ABSTRACT FROM AUTHOR]

Semiconductor quantum wires are expected to exhibit larger optical nonlinearities. However, linear and nonlinear optical absorption in laterally-coupled semiconductor quantum wires are few studied due to the difficulty in obtaining their quantum states. Here, we report the first study of linear and nonlinear optical absorption of the laterally-coupled Al x Ga 1−x As/GaAs quantum wires using the effective mass approximation. Numerical method is applied to the calculation of the energy levels and the wave functions of the system by the diagonalization of the Hamiltonian matrix. It is found that the linear and nonlinear absorption coefficients exhibit a blue shift with decreasing gap and that their resonant peak values in strong coupled regime are greatly enhanced in contrast to those in weak coupled regime. Furthermore, for the resonant peak values, a monotonous increase of the linear term with decreasing gap is exhibited while a non-monotonous variation of the nonlinear term is observed. It is also found that the linear and nonlinear optical absorption coefficients experience a red shift with the increase of the radius and that the resonant peak values of linear term decrease with increasing radius while those of nonlinear term changes in the opposite trend simultaneously. Our results are of more crucial importance for the design and optimization of optoelectronic devices such as infrared detectors and ultrafast optical switches. [ABSTRACT FROM AUTHOR]

CO 2 concentration [CO 2 ] level in artificial ecosystems such as greenhouse agriculture and space farming can easily exceed 1000 μmol mol −1 (or ppm). In order to understand how the growth and development in crop plants may respond to elevated CO 2 , it is necessary to determine if crop leaves in the closed artificial ecosystem have a fully developed photosynthetic apparatus, and whether or not photosynthesis in these leaves is more responsive to elevated CO 2 concentration. To address this issue, we evaluated the response of photosynthetic characteristics, leaf water status and antioxidant capacity of Chufa ( Cyperus esculentus L.), which is a sedge-like plant with 1–2 cm small sweet tubers in length, under elevated CO 2 concentrations in an artificial closed ecosystem. The results showed that Chufa plants cultivated in the elevated CO 2 environment from the seedling stage to the maturity stage were characterized by more appropriate chlorophyll content and photosynthetic rate. The photosynthetic rate of Chufa plants in the 1000 and 3000 ppm treatments was no significant difference with that in 500 ppm CO 2 condition both at seedling stage and rapid growth stage. All the treatments had a high relative water content (RWC) about 60% at the maturity stage. However, there was no significant difference in membrane stability index (MSI) at the rapid growth stage. The antioxidase enzymes activities experienced a rise and a drop and reached the peak at the rapid growth stage. Elevated CO 2 , especially more than 1000 ppm conditions, may accelerant Chufa plants aging process. [ABSTRACT FROM AUTHOR]

A kind of novel compound Ba 1-x (Zr,Ti)Si 3 O 9 :xEu simultaneously activated by different-valence Eu 2+ and Eu 3+ ions has been successfully synthesized. The existence of Ti 4+ -O 2- charge transfer (CT) transitions in Ba 1-x ZrSi 3 O 9 :xEu is proved by the photoluminescence spectra and first principle calculations, and the Ti 4+ ions come from the impurities in commercial ZrO 2 raw materials. Under the excitation of multi-wavelength ultraviolet radiation (λ EX  = 392, 260, 180 nm), Ba 1-x ZrSi 3 O 9 :xEu (x = 0.15) can directly emit nearly white light. The coexistence of multiple luminescent centers and the energy transfer among Zr 4+ -O 2- CT state, Ti 4+ -O 2- CT state, Eu 2+ and Eu 3+ ions play important roles in the white light emission. Ba 1-x ZrSi 3 O 9 :xEu (x = 0.15) has good thermal stability, in particular, the intensity of emission spectrum (λ EX  = 392 nm) at 150 °C is ∼96% of that at room temperature. In general, the multi-wavelength ultraviolet-excited single-phase white light emitting phosphor Ba 1-x (Zr,Ti)Si 3 O 9 :xEu possesses a promise for applications in white light emitting diodes (WLEDs), agriculture, medicine and other photonic fields. [ABSTRACT FROM AUTHOR]

In this paper we report the development of a cost-effective, modular, open source, and fully automated slide-scanning microscope, composed entirely of easily available off-the-shelf parts, and capable of bright field and fluorescence modes. The automated X-Y stage is composed of two low-cost micrometer stages coupled to stepper motors operated in open-loop mode. The microscope is composed of a low-cost CMOS sensor and low-cost board lenses placed in a 4f configuration. The system has approximately 1 micron resolution, limited by the f/# of available board lenses. The microscope is compact, measuring just 25×25×30 cm, and has an absolute positioning accuracy of ±1 μm in the X and Y directions. A Z-stage enables autofocusing and imaging over large fields of view even on non-planar samples, and custom software enables automatic determination of sample boundaries and image mosaicking. We demonstrate the utility of our device through imaging of fluorescent- and transmission-dye stained blood and fecal smears containing human and animal parasites, as well as several prepared tissue samples. These results demonstrate image quality comparable to high-end commercial microscopes at a cost of less than US$400 for a bright-field system, with an extra US$100 needed for the fluorescence module. [ABSTRACT FROM AUTHOR]

A green process for the synthesis of supported Pd nanoparticles (NPs) using poplar leaf extract (PLE) as a reducing agent and the extracted residue of poplar leaf (RPL) as a carrier is reported. The Pd/RPL nanocomposites were characterized by XRD, TEM, SEM, EDS, XPS, FTIR, and ICP-AES. The spherical Pd NPs had a mean particle size of 3.1 nm and were evenly distributed on the RPL surface. More importantly, the Pd/RPL nanocomposites were used as a heterogeneous catalyst, which presented superior catalytic activity for the Suzuki coupling reaction. In addition, only a slight loss in the catalytic activity was observed after six recycles. [ABSTRACT FROM PUBLISHER]

A green method for the synthesis of supported Pd nanoparticles (NPs) using pine needle extract as the reducing agent and the extracted residue of pine needle (RPN) as the carrier is described. The Pd/RPN nanocomposites were characterized using Fourier transform infrared, UV-visible, inductively coupled plasma atomic emission and X-ray photoelectron spectroscopies, transmission electron microscopy and X-ray diffraction. The spherical Pd NPs had a mean particle size of 3.25 nm and were evenly distributed on the RPN surface. More importantly, the Pd/RPN nanocomposite, as a heterogeneous catalyst, presented superior catalytic activity for the Suzuki coupling reaction. The yield of the reaction of 4-bromotoluene with phenylboronic acid catalyzed by Pd0.03/RPN reached 98% with low Pd loading (0.1 mmol%) at room temperature for 30 min. In addition, the catalyst could be easily separated by centrifugation and reused at least six times without significant loss of activity. [ABSTRACT FROM AUTHOR]

A green route for the synthesis of palladium (Pd) nanoparticles (Pd NPs) employing Poplar leaf extract as a reducing and capping agent is described. The as‐prepared Pd NPs are spherical with a face centred cubic structure, a particle distribution of 2.2–6.8 nm and an average particle size of 4.2 nm. The application of this catalyst toward homogeneous Suzuki coupling reactions was investigated. The Pd NPs afforded a yield of 98.86% in the Suzuki coupling reaction of 4‐bromotoluene with phenylboronic acid using 0.01 mmol% of the catalyst at 60°C for 30 min under an air atmosphere. [ABSTRACT FROM AUTHOR]

Nonlinear optical rectification coefficient χ 0 ( 2 ) in laterally-coupled Al x Ga 1−x As/GaAs quantum well wires with an applied electric field is theoretically investigated using the effective mass approximation as well as the numerical energy levels and wavefunctions of electrons. We find that χ 0 ( 2 ) is greatly influenced by the electric field as well as both the distance and the radius of the coupled system. A blue shift of χ 0 ( 2 ) with increasing electric field is exhibited while a red shift followed by a blue shift with increasing distance or radius is exhibited. A nonmonotonic behavior can be found in the resonant peak values of χ 0 ( 2 ) along with the increase of the electric field, the distance or the radius. One or two of the following physical mechanisms: the increased localization of the ground and first-excited states, the reduced coupling and the reduced quantum confinement effect are applied to elucidate the results above. Our results play a potential role in infrared photodetectors based on the coupled system. [ABSTRACT FROM AUTHOR]

For spherical semiconductor nanoshells, nonlinear optical rectification is suppressed due to their spherical symmetry. Here, we design a structure, called spherical dome semiconductor nanoshells, to realize nonlinear optical rectification. Numerical energy levels and wave functions are applied to the calculation of nonlinear optical rectification in this structure. We discuss the dependence of nonlinear optical rectification on the cut-off angle and the inner and external radius. Our results show that with the increase of the cut-off angle, the magnitude of nonlinear optical rectification increases and its resonant peak doesn't shift. Through the modulation of the inner and external radius, the resonant peak of optical rectification can be tuned effectively. This structure holds great potential for the development of optoelectronic devices such as optical modulators and photodetectors. [ABSTRACT FROM AUTHOR]

Zeolite can increase fertilizer use efficiency in rice production. Zeolite's positive effect on nitrogen (N) and phosphorus (P) utilization has been validated in lowland paddy fields, but little information is available on its effect on P accumulation, translocation, and partitioning in lowland rice, especially under water stress. We conducted a two-year field experiment to evaluate the effect of zeolite and irrigations on soil P availability, dry matter accumulation, and P accumulation, partitioning, and translocation. Regardless of irrigation, zeolite application accumulated greater dry matter (DM) across growth stages than the non-zeolite control (Z 0). A zeolite application rate of 10 t ha−1 (Z 10) increased soil available P, plant P accumulation, stem and leaf P translocation, and panicle P partitioning across growth stages compared to Z 0. Z 10 increased grain yield, water use efficiency (WUE), and economic benefit by 21.4%, 35.5%, and 20.9%, respectively, compared to Z 0. For the irrigation treatments, alternate wetting and drying irrigation (AWD) increased DM and shoot P accumulation at all stages (except DM at tillering and shoot P accumulation at tillering and yellow ripening) relative to continuous flooding (CF). AWD produced similar grain yields but higher WUE than CF. Significant correlations between grain yield, shoot P accumulation, and soil available P indicated that zeolite enhanced grain yield by improving soil P availability and plant P uptake. These results showed that 10 t ha−1 zeolite combined with AWD irrigation achieved the highest soil available P, plant P accumulation, grain yield, WUE, and economic benefit, and could be an alternative management option for improving fertilizer P utilization, increasing rice production, and enhancing farmer profits in water-deficient regions. • Zeolite application increased soil P availability and plant P accumulation. • Zeolite application (10 t ha−1) increased P translocation in stems and leaves and P partitioning in panicles. • Grain yield positively correlated with shoot P accumulation and soil P availability. • Zeolite application (10 t ha−1) combined with AWD achieved the highest grain yield, WUE, and economic benefit. [ABSTRACT FROM AUTHOR]

Elevated atmospheric CO 2 has been shown to rapidly alter plant physiology and ecosystem productivity, but contemporary ecological responses to increased CO 2 have yet to be studied in a controlled closed ecosystem with humans. To test this concept, at an integrated ground-based Bioregenerative Life Support System (BLSS) named Lunar Palace-1, we tested elevated CO 2 effects on gas exchange characteristics in an experiment involving humans. During the whole experimental process, researchers monitored CO 2 and O 2 concentrations in different plant growth and human occupied cabins on a real time basis. By turning off lighting and air ventilation system, elevated CO 2 effects were measured in plant chamber and overall facility during a 1 h period. The results indicated that elevated CO 2 had variable effects on plant photosynthetic and respiration rates. Photosynthesis in most plants is typically not saturated with respect to carbon dioxide at 400 ppm. Elevated CO 2 has inhibitory effects on plant respiration. Photosynthesis is strengthened and respiration is reduced in a closed artificial ecosystem were demonstrated under high levels of CO 2 . Our findings in this closed ecosystem may serve as key baseline design data for larger, long-term and higher degree of closure BLSS integration experiment planned for the near future. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) play important roles in pulmonary artery hypertension (PAH). Recently, it has been reported that miR-199a-5p participates in the progression of chronic obstructive pulmonary disease, ventricular hypertrophy and heart failure. However, the roles of miR-199a-5p in PAH are still unclear. In the present study, miR-199a-5p was investigated in PAH rat models and in human pulmonary artery smooth muscle cells (HPASMCs) and endothelial cells (HPAECs). The expression of miR-199a-5p was significantly increased following PAH induction, and anti-miR-199a-5p could increase the nitric oxide (NO) level and decrease the PAH-induced upregulation of pulmonary artery pressure and right ventricular hypertrophy. Moreover, in HPASMCs and HPAECs, miR-199a-5p overexpression could inhibit the level of NO and promote the concentration of Ca 2+ , but anti-miR-199a-5p showed opposite results. Further analysis demonstrated that miR-199a-5p attenuated the expression of Smad3. Importantly, Smad3 was confirmed to be the target gene of miR-199a-5p using dual-luciferase reporter assay. Mechanism analyses revealed that the downregulation of NO and the upregulation of Ca 2+ caused by miR-199a-5p were all reversed by Smad3 overexpression in HPASMCs and HPAECs. Moreover, in PAH model, Smad3, p-Smad3 and Smad4 were all downregulated in lung tissues, and SIS3 (Smad3 inhibitor) could reverse the effects of anti-miR-199a-5p in PAH rats. Our date suggest that miR-199a-5p may function as a regulator of PAH by targeting Smad3, indicating a novel therapeutic strategy for patients with PAH. [ABSTRACT FROM AUTHOR]

A bioregenerative life support system (BLSS) is an artificial closed ecosystem which provides basic human life support for long-duration and far-distance space activities such as lunar bases. “Lunar Palace 1”, an experimental facility, was constructed by our team for the integration research of the key technologies in BLSS, and then a continuous 105-day closed integrative BLSS experiment was carried out in “Lunar Palace 1”(Stage I) successfully last year. In such a system, O 2 produced by higher plants is supplied for the breathing of the crew, as well as the respiration of microorganisms which decompose the solid wastes such as inedible plant biomass and human wastes, while CO 2 produced by the crew and microorganisms is provided for plants to grow. In the system, an excessively high CO 2 level can affect plant growth and may harm human health, however, if the CO 2 level is too low, plant growth may also be inhibited. Thus, keeping the balance between CO 2 and O 2 levels is essential to the gas regulation in the system, and is one of the key points for the operation stability of the system. In this study, an efficient and controllable solid waste bio-convertor was built based on the microbial fermentation in “Lunar Palace 1”, and the CO 2 generation of the bio-convertor under the optimum fermentation conditions in the 105-day airtight experiment was monitored. Moreover, the changes of CO 2 production along with increasing or reducing the temperature of the bio-convertor from 33 to 45 °C (or from 45 to 33 °C) were also investigated, and a positive correlation between the CO 2 output and the fermentation temperature was obtained accordingly. Therefore, the CO 2 production can be adjusted effectively by changing the temperature of the bio-convertor, which implies that it is feasible to regulate the balance between the CO 2 and O 2 concentrations in BLSS by controlling the fermentation conditions of the solid waste treatment unit. The results of this study could lay a foundation for the following researches conducted in “Lunar Palace 1”. [ABSTRACT FROM AUTHOR]

Tunable white light was realized in samples BaTiPO:2 xEu ( x = 0-0.80) by introducing orange-red light emitting Eu in self-activated blue-green light emitting matrix BaTiPO. The sample BaTiPO:2 xEu is a multiphase system consisting of BaTiPO, EuPO and TiO when x is greater than or equal to 0.20. The tunable light from blue-green to bluish-white, to white, and eventually to pinky-white of samples BaTiPO:2 xEu under UV light excitation is attributed to the light mixture of tunable blue-green light from Ti-O charge transfer transition in BaTiPO and orange-red light from Eu 4f-4f transition mostly in EuPO. The Commission International de l'Eclairage chromaticity coordinates, correlated color temperature and color rendering index were tuned from (0.262, 0.339), 9492 K and 74 for matrix sample BaTiPO to (0.324, 0.346), 5876 K and 87 for sample BaTiPO:2 xEu ( x = 0.40) under UV light excitation. Therefore, a kind of promising UV-excited white light emitting multiphase phosphor was obtained. [ABSTRACT FROM AUTHOR]

In this clinical study, we have compared routine diagnostic dose 131I scan and TcO4-99m thyroid scintigraphy with therapeutic dose 131I imaging for accurate thyroid remnant estimation after total thyroidectomy. We conducted a retrospective review of the patients undergoing total thyroidectomy for differentiated thyroid carcinoma (DTC) and subsequently receiving radioactive iodine (RAI) treatment to ablate remnant thyroid tissue. All patients had therapeutic dose RAI whole body scan, which was compared with that of diagnostic dose RAI, TcO4-99m thyroid scan, and ultrasound examination. We concluded that therapeutic dose RAI scan reveals some extent thyroid remnant in all DTC patients following total thyroidectomy. Diagnostic RAI scan is much superior to ultrasound and TcO4-99m thyroid scan for the postoperative estimation of thyroid remnant. Ultrasound and TcO4-99m thyroid scan provide little information for thyroid remnant estimation and, therefore, would not replace diagnostic RAI scan. [ABSTRACT FROM AUTHOR]

Luminescent Ag nanoclusters doped solid host, such as glass, are very promising new materials for lighting applications due to their good mechanical and optical properties. In the present work, transparent Ag nanoclusters doped oxyfluoride amorphous glasses, having starting composition of 30SiO 2 –70PbF 2 – x AgNO 3 ( x =0, 0.5, 3 mol%), were prepared using melt quenching technique. The Ag nanoclusters are spontaneously created during the casting of glass. The prepared Ag nanoclusters doped glasses emit green-yellow light under exposure to UV lamp ( λ ex =365 nm). The emission spectra of Ag nanoclusters doped glass show a red shift with the increase of excitation wavelength, and the excitation spectra show a similar red shift, that comes from Ag nanoclusters with different sizes and different local surroundings. The decay time of the Ag nanoclusters doped glass detected at the optimum wavelength ( λ ex =370 nm, λ em =530 nm) is only 2.1 ns, which may be attributed to the spin allowed singlet–singlet transitions of Ag 4 2+ tetramers. High temperature photoluminescence spectra of the glass ( x =3) show a slight decrease in luminescence intensity with the increase of temperature, and the luminescence intensity at 80 °C is about 60% of that at 25 °C. The Ag nanoclusters were effectively protected and stabilized by the 30SiO 2 –70PbF 2 glass host. [ABSTRACT FROM AUTHOR]

Excitonic effects on linear and nonlinear optical absorption coefficients (OAC) and refractive index changes (RIC) in one-dimensional quantum dots with linear potential are theoretically investigated within the framework of the compact-density-matrix approach and iterative method. It is found that linear and nonlinear OAC and RIC with excitonic effects in one-dimensional quantum dots are larger than that without excitonic effects. Besides, when excitonic effects are considered, our results show a remarkable dependence of linear and nonlinear OAC and RIC on linear potential. [ABSTRACT FROM AUTHOR]

Linear and nonlinear optical absorption coefficients of spherical dome shells are theoretically investigated within analytical wave functions and numerical quantized energy levels. Our results show that the inner radius, the outer radius and the cut-off angle of spherical dome shells have great influences on linear and nonlinear optical absorption coefficients as well as the total optical absorption coefficients. It is found that with the increase of the inner radius and the outer radius, linear and nonlinear optical absorption coefficients exhibit a blueshift and a redshift, respectively. However, with the increase of the cut-off angle, linear and nonlinear optical absorption coefficients do not shift. Besides, the resonant peaks of linear and nonlinear optical absorption coefficients climb up and then decrease with increasing the cut-off angle. The influences of the incident optical intensity on the total optical absorption coefficients are studied. It is found that the bleaching effect occurs at higher incident optical intensity. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel magnetic MXene@Fe 3 O 4 /Au/polydopamine (PDA) nanosheet is developed. • MXene provides more uniformly dispersed active sites for Au nanocrystals. • PDA-confined-Au-nanocrystals hybrid shell is achieved by a simple one-step method. • The MXene@Fe 3 O 4 /Au/PDA nanosheet has excellent photothermal conversion property. • The nanosheet exhibits magnetically-enhanced photothermal antibacterial activity. • The edge of the nanosheet cut the cytomembrane similar to a magnetic "hot nanoblade". Harmful bacteria are common substances in water that endanger human health, so it is urgent to establish a simple system that can tackle these hazardous substances simultaneously. In this work, a novel magnetic MXene@Fe 3 O 4 /Au/polydopamine (PDA) nanosheet with excellent photothermal-magnetolytic coupling antibacterial performance is developed. MXene, Au and polydopamine all have good photothermal properties, so the photothermal conversion efficiency of the MXene@Fe 3 O 4 /Au/PDA nanosheet reaches as high as 48.7%. After 6 min of 808 nm laser irradiation, the MXene@Fe 3 O 4 /Au/PDA nanosheets (120 μg·mL−1) can achieve nearly 100% antibacterial effect against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). In comparison to the sole photothermal treatment, the nanosheet at lower concentration (80 μg·mL−1) also exhibit stronger antibacterial properties against both Gram-negative and Gram-positive bacteria during the photothermal-magnetic coupling treatment. The result is mainly because the heat generated by the photothermal effect of the nanosheet is directly transferred to the cell membrane, and the edge of the nanosheet cuts the cytomembrane similar to a magnetic "hot nanoblade", resulting in subsequent shrinkage, deformation and even rupture. [ABSTRACT FROM AUTHOR]

The carbon amounts of simulated syngases with different compositions were calculated in this study. The degradation and carbon deposition behavior of solid oxide fuel cells (SOFCs) with an active area of 4 cm × 4 cm were then investigated under the simulated syngases at work conditions. Carbon deposition occurred over time with a little or no HO and CO in these gasses, which significantly degraded the single cells. The cell stabilized within 1 h under a gas mixture of 70 % H-30 % CO because of the chocking of inlet pipelines of the testing house by carbon deposition. Addition of proper HO and CO in the simulated syngas effectively suppressed carbon deposition in the pipelines. However, carbon was still deposited gradually in the single cell anode when HO and CO were insufficient. The mechanisms of carbon deposition were different when the cells were exposed under different syngases. Single cells steadily thrived under 50 % H-20 % CO-10 % CO-20 % HO and 50 % H-20 % CO-20 % CO-10 % HO gas mixtures for about 2000 h without carbon deposition. [ABSTRACT FROM AUTHOR]

In OFDM system, channel estimator with fixed-coefficient interpolation gives rise to significant estimation errors when the estimator mismatches the experienced time-varying channel. This paper presents a pilot-aided channel estimator adopting a double one-dimensional (1-D) polyphase subfilter structure, in which a few interpolating coefficients are applicable to all subcarriers of an OFDM symbol. By analyzing the channel interpolation for OFDM receiver, we propose a two-dimensional (2-D) adaptation scheme of the interpolating coefficient, based on a block least-mean-square algorithm, which requires none of knowledge on channel statistics. The 2-D adaptation scheme is simplified as two types of 1-D schemes respectively for the time and frequency dimensions, based on the known frequency- and time-direction interpolating coefficients. By simultaneously exploiting channel correlation in the time and frequency dimensions, the adaptive interpolators are trained to match channel properties. Furthermore, the proposed schemes of adaptive interpolation demand lower implementation cost, compared with the existing methods. Simulation results show that the adaptive interpolators converge at a high rate, and that the simplified schemes outperform the conventional methods in the high-speed mobile channel and the single-frequency-networks channel with long-delay echoes, while preserving a low implementation complexity. [ABSTRACT FROM AUTHOR]

Objective To isolate, purify, and cultivate primary retinal microvascular pericytes ( RMPs) from rats to facilitate the study of their properties in vitro. Methods Primary RMPs were isolated from weanling rats by mechanical morcel and collagenase digestion, and purified by a step-wise combination of selective medium with different glucose concentrations, medium exchange, and partial enzymatic digestion. Morphology of RMPs was assessed by phase contrast microscopy. Further characterization was analyzed by immunofluorescence. Functional assay was evaluated by the pericytes- endothelial cells ( ECs) coculture system. Results Retinal microvascular pericytes migrated out of microvascular fragments after 24-48 hours of plating and reached subconfluence on days 14-16. The cells showed typical pericyte morphology with large irregular triangular cell bodies and multiple long processes, and uniformly expressed the cellular markers α-SMA, PDGFR- β, NG2 and desmin, but were negative for vWF, GS, GFAP and SMMHC. Ninety-nine percent of the cell population had double positive staining for α-SMA and PDGFR- β. In the coculture system, RMPs can directly contact ECs and move together to form the capillary-like cords. Conclusions Retinal microvascular pericytes can be readily obtained by our method. We report the first cultivation of primary RMPs from rats and establish a simple method for their isolation and purification. [ABSTRACT FROM AUTHOR]