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Rare‐earth (RE) silicates environmental barrier coatings (EBCs) are prone to accelerate failure resulted from molten calcium–magnesium–aluminum silicate (CMAS), which presents significant challenges to the design and development of durable EBCs. In this study, X1‐Gd2SiO5 and X2‐Er2SiO5 coatings were explored on their corrosion resistance to CMAS melts with different Ca/Si ratios (1.1, 0.75, 0.64, and 0.42) at 1350°C for 25 and 50 h, respectively. Results showed that with the Ca/Si ratio increasing, CMAS viscosity decreased and a more intense corrosion reaction with coatings occurred. Garnet phase was only observed in X2‐Er2SiO5 coating corroded by CMAS with high Ca/Si ratios, which could be beneficial for improving corrosion resistance. The X2‐Er2SiO5 phase, which is composed of [SO4] and [REO6]/[REO7] polyhedrons, exhibits better corrosion resistance due to its more stable crystal structure, lower reactivity with CMAS, and the radius difference between the RE ions and Ca2+. [ABSTRACT FROM AUTHOR]

Yb2SiO5 and Yb2Si2O7 have been considered to be promising environmental barrier coatings (EBCs) materials for silicon‐based ceramics. Besides the various requirements EBCs must satisfy, it must be resistant to severe corrosion by high‐temperature water vapor as well as CMAS. In this work, the Yb2SiO5, Yb2Si2O7 coatings and Yb2SiO5/Yb2Si2O7/Si, Yb2SiO5/Si EBCs were subjected to steam with alumina at 1400°C for 200 h. Results showed that Yb3Al5O12 reaction layer and Yb2SiO5 corrosion layer were formed on the Yb2SiO5 coating, while porous Yb2SiO5 corrosion layer with Yb3Al5O12 phase was formed on the Yb2Si2O7 coating. By designing Yb2Si2O7 as intermediate layer, the corrosion resistance of Yb2SiO5/Yb2Si2O7/Si EBCs was significantly improved. In addition to phase transition of β‐cristobalite to α‐phase, crystallization of amorphous SiO2 also caused volume change, inducing longitudinal cracks through the TGO layer, which may lead to the failure of EBCs. [ABSTRACT FROM AUTHOR]

The Cu–1.1 wt% Hf–0.1 wt% Si alloy containing various precipitates is studied as a novel precipitation‐strengthened alloy with high strength and high electrical conductivity. The Cu–Hf–Si alloy prepared by solution, cold rolling, and aging processes exhibits a hardness of 238.92 HV, a tensile strength of 691.01 MPa, a breaking elongation of 15.09%, and an electrical conductivity of 62.34% International Annealed Copper Standard. The optimal peak aging parameter for Cu–Hf–Si alloy is 430 °C for 90 min. The precipitation of Hf and Si atoms from the Cu matrix is helpful to enhance the electrical conductivity. The precipitation of Hf can produce fibrous Guinier Preston zone and γ' precipitate, as well as spherical Cu10Hf7 phases. In addition, the coprecipitation of Si and Hf can also produce Hf3(Cu2Si)2 and HfCuSi phases. The high strength of Cu–Hf–Si alloy is mainly due to the multiprecipitates synergistic strengthening. [ABSTRACT FROM AUTHOR]

In this article, the design problem of an event‐triggered composite anti‐disturbance dissipative control (ECADC) based on nonlinear disturbance observer (NLDO) is considered for a class of nonlinear stochastic systems. These systems comprise quantized inputs and multiple noises including nonlinear disturbances and multiplicative noises. First, a NLDO‐based control scheme is constructed to estimate and then compensate the noise modeled by the nonlinear exosystem. Then, an event‐triggered scheme and a quantized input technique are adopted to alleviate the channel transmission pressure. Subsequently, by combining dissipative control theory, an ECADC design method is developed such that the closed‐loop system is dissipative in the presence of multiple noises. Finally, the effectiveness of the proposed control scheme is validated through numerical simulations. [ABSTRACT FROM AUTHOR]

Summary: This paper investigates the design problem of composite antidisturbance control for a class of nonlinear systems with multiple disturbances. First, a novel nonlinear disturbance observer‐based control scheme is constructed to estimate and compensate the disturbance modeled by the nonlinear exosystem. Then, by combining the dissipative control theory, a linear matrix inequality‐based design method of composite antidisturbance control is developed such that the augmented system is exponentially stable in the absence of unmodeled disturbances, and is dissipative in the presence of unmodeled disturbances. In this case, the original closed‐loop system is exponentially stable in the presence of modeled disturbances. Subsequently, two special cases of composite antidisturbance control are derived with H∞ performance and passivity, respectively. Finally, the proposed method is applied to control A4D aircraft to show its effectiveness. [ABSTRACT FROM AUTHOR]

In this paper, a design problem of low dimensional disturbance observer-based control (DOBC) is considered for a class of nonlinear parabolic partial differential equation (PDE) systems with the spatio-temporal disturbance modeled by an infinite dimensional exosystem of parabolic PDE. Motivated by the fact that the dominant structure of the parabolic PDE is usually characterized by a finite number of degrees of freedom, the modal decomposition method is initially applied to both the PDE system and the PDE exosystem to derive a low dimensional slow system and a low dimensional slow exosystem, which accurately capture the dominant dynamics of the PDE system and the PDE exosystem, respectively. Then, the definition of inputto- state stability for the PDE system with the spatio-temporal disturbance is given to formulate the design objective. Subsequently, based on the derived slow system and slow exosystem, a low dimensional disturbance observer (DO) is constructed to estimate the state of the slow exosystem, and then a low dimensional DOBC is given to compensate the effect of the slow exosystem in order to reject approximately the spatiotemporal disturbance. Then, a design method of low dimensional DOBC is developed in terms of linear matrix inequality to guarantee that not only the closed-loop slow system is exponentially stable in the presence of the slow exosystem but also the closed-loop PDE system is input-to-state stable in the presence of the spatio-temporal disturbance. Finally, simulation results on the control of temperature profile for catalytic rod demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

This paper presents a design method of finite dimensional robust H ∞ distributed consensus filters (DCFs) for a class of dissipative nonlinear partial differential equation (PDE) systems with a sensor network, for which the eigenvalue spectrum of the spatial differential operator can be partitioned into a finite dimensional slow one and an infinite dimensional stable fast complement. Initially, the modal decomposition technique is applied to the PDE system to derive a finite dimensional ordinary differential equation system that accurately describes the dynamics of the dominant (slow) modes of the PDE system. Then, based on the slow subsystem, a set of finite dimensional robust H ∞ DCFs are developed to enforce the consensus of the slow mode estimates and state estimates of all local filters for all admissible nonlinear dynamics and observation spillover, while attenuating the effect of external disturbances. The Luenberger and consensus gains of the proposed DCFs can be obtained by solving a set of linear matrix inequalities (LMIs). Furthermore, by the existing LMI optimization technique, a suboptimal design of robust H ∞ DCFs is proposed in the sense of minimizing the attenuation level. Finally, the effectiveness of the proposed DCFs is demonstrated on the state estimation of one dimensional Kuramoto-Sivashinsky equation system with a sensor network. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A concept of interval-valued triangular fuzzy soft set is presented, and some operations of "AND," "OR," intersection, union and complement, and so forth are defined. Then some relative properties are discussed and several conclusions are drawn. A dynamic decision making model is built based on the definition of interval-valued triangular fuzzy soft set, in which period weight is determined by the exponential decay method. The arithmetic weighted average operator of interval-valued triangular fuzzy soft set is given by the aggregating thought, thereby aggregating interval-valued triangular fuzzy soft sets of different time-series into a collective interval-valued triangular fuzzy soft set. The formulas of selection and decision values of different objects are given; therefore the optimal decision making is achieved according to the decision values. Finally, the steps of this method are concluded, and one example is given to explain the application of the method. [ABSTRACT FROM AUTHOR]

Objective. To investigate the effect of beraprost sodium (BPS) on diabetic cardiomyopathy and the underlying mechanism. Methods. A total of 40 Sprague Dawley rats were randomly divided into the normal control group (N = 10) and the model group (N = 30). The model group was fed a high-fat diet followed by a one-time dose of streptozotocin (STZ) to establish the diabetes mellitus model. After that, rats were randomly divided into two groups with or without BPS intervention. After 8 weeks, we explored the role of the p38 MAPK signaling pathway in inflammation, oxidative stress, cardiac morphology, and myocardial apoptosis. Results. Compared with control, the ratio of heart-weight to body-weight and the serum levels of SOD and GSH in the BPS group significantly increased, the expression of p38 MAPK, the serum levels of MDA, TGF-ß1, TNF-α, HIF-1α, MMP-9, caspase-3, BNP, ANP, and heart Bax expression significantly decreased, and heart Bcl-2 expression significantly increased. H&E staining in diabetic rats showed the cardiac muscle fibers derangement, the widening gap, the pyknotic and fragmented nuclei, and more apoptosis. Conclusions. BPS effectively showed protective effects on diabetic myocardial cells, possibly through the inhibition of p38 MAPK signaling pathway. [ABSTRACT FROM AUTHOR]

Salmonella enterica serovar Typhi (S. Typhi) is a human-specific pathogen that causes typhoid fever. In this study, we constructed ΔygaE mutant and a microarray was performed to investigate the role of ygaE in regulation of gene expression changes in response to hyperosmotic stress in S. Typhi. qRT-PCR was performed to validate the microarray results. Our data indicated that ygaE was the repressor of gab operon in S. Typhi as in Escherichia coli (E. coli), though the sequence of ygaE is totally different from gabC (formerly ygaE) in E. coli. OmpF, OmpC, and OmpA are the most abundant out membrane proteins in S. Typhi. Here we report that YgaE is a repressor of both OmpF and OmpC at the early stage of hyperosmotic stress. Two-dimensional electrophoresis was applied to analyze proteomics of total proteins in wild-type strain and ΔygaE strain and we found that YgaE represses the expression of OmpA at the late stage of hyperosmotic stress. Altogether, our results implied that YgaE regulates out membrane proteins in a time-dependent manner under hyperosmotic stress in S. Typhi. [ABSTRACT FROM AUTHOR]

Cyclosporine, tacrolimus, and sirolimus are commonly used in renal transplant recipients to prevent rejection. However, information for comparative effects of these agents on the male productive system is extremely limited and controversial. In a physiologically and clinically relevant rat model of unilateral nephrectomy, we demonstrated that long-term oral administration of both cyclosporine and sirolimus at doses equivalent to the therapeutic levels used for postrenal transplant patients significantly affects testicular development and the hypothalamic-pituitary-gonadal axis accompanied by profound histological changes of testicular structures on both light and electron microscopic examinations. Spermatogenesis was also severely impaired as indicated by low total sperm counts along with reduction of sperm motility and increase in sperm abnormality after treatment with these agents, which may lead to male infertility. On the other hand, treatment with therapeutic dose of tacrolimus only induced mild reduction of sperm count without histological evidence of testicular injury. The current study clearly demonstrates that commonly used immunosuppressants have various impacts on male reproductive system even at therapeutic levels. Our data provide useful information for the assessment of male infertility in renal transplant recipients who wish to father children. Clinical trials to address these issues should be urged. [ABSTRACT FROM AUTHOR]

Recent evidence supported the presence of a local renin-angiotensin system (RAS) in the pancreas, which is implicated in many physiological and pathophysiological processes.We utilized small interfering RNA (siRNA) to investigate the effects of angiotensin II type 1 receptor (AT1R) knockdown on glucose-stimulated insulin secretion (GSIS) in isolated islets of db/db mice and to explore the potential mechanisms involved.We found thatAd-siAT1R treatment resulted in a significant decrease both inAT1RmRNAlevel and in AT1R protein expression level. With downexpression of AT1R, notable increased insulin secretion and decreased glucagon secretion levels were found by perifusion. Simultaneously, significant increased protein levels of IRS-1 (by 85%), IRS-2 (by 95%), PI3K(85) (by 112.5%), and p-Akt2 (by 164%) were found by western blot. And upregulation of both GLUT-2 (by 190%) and GCK (by 121%) was achieved after AT1R inhibition by Ad-siAT1R. Intraislet AT1R expression level is a crucial physiological regulator of insulin sensitivity of β cell itself and thus affects glucose-induced insulin and glucagon release. Therefore, the characteristics of AT1R inhibitors could make it a potential novel therapeutics for prevention and treatment of type 2 diabetes. [ABSTRACT FROM AUTHOR]

Xing X-F, Li H, Zhong X-Y, Zhang L-H, Wang X-H, Liu Y-Q, Jia S-Q, Shi T, Niu Z-J, Peng Y, Du H, Zhang G-G, Hu Y, Lu A-P, Li J-Y, Chen S & Ji J-F (2011) Histopathology 59, 198-206 Phospholipase A2 group IIA expression correlates with prolonged survival in gastric cancer Aims: The secreted phospholipase A2 type IIA (PLA2G2A) gene has been identified as a modifier of intestinal adenoma multiplicity in ApcMin/+ mice. The aim of the present study was to analyse the clinical significance of PLA2G2A expression in human gastric cancer. Methods and results: Using immunohistochemistry, cytoplasmic immunoreactivity of PLA2G2A was observed in 27% (40 of 149) of gastric cancer tissues compared with negative staining in normal mucosa. The PLA2G2A expression rate in well-differentiated carcinoma was elevated significantly compared with that in poorly differentiated carcinoma (46% versus 19%, P = 0.001). Statistical analysis also revealed that PLA2G2A expression correlated negatively with depth of mural invasion, lymph node metastasis and tumour-node-metastasis (TNM) stage ( P < 0.05). Patients with positive PLA2G2A expression showed higher 5-year overall survival than those with negative expression ( P = 0.0004). In intestinal metaplasia, PLA2G2A was found to be abundant in Paneth cells. The coexistence of PLA2G2A and lysozyme was observed in Paneth cell-rich gastric cancer ( P < 0.0001). Conclusions: PLA2G2A may predict survival and might be a potential biomarker for early detection and individualized therapy. [ABSTRACT FROM AUTHOR]

Wang Z, Yang S, Shi H, Du H, Xue L, Wang L, Dong Y & Han A (2011) Histopathology [ABSTRACT FROM AUTHOR]

Purpose: Electronic portal imaging devices based on megavoltage (MV), active matrix, flat-panel imagers (AMFPIs) are presently regarded as the gold standard in portal imaging for external beam radiation therapy. These devices, employing indirect detection of incident radiation by means of a metal plate plus phosphor screen combination, offer a quantum efficiency of only ∼2% at 6 MV, leading to a detective quantum efficiency (DQE) of only ∼1%. In order to significantly improve the DQE performance of MV AMFPIs, a strategy based on the development of direct detection imagers incorporating thick films of polycrystalline mercuric iodide (HgI2) photoconductor was undertaken and is reported. Methods: Two MV AMFPI prototypes, one incorporating an ∼300 μm thick HgI2 layer created through physical vapor deposition (PVD) and a second incorporating an ∼460 μm thick HgI2 layer created through screen-printing of particle-in-binder (PIB) material, were quantitatively evaluated using a 6 MV photon beam. The reported measurements include empirical determination of x-ray sensitivity, lag, modulation transfer function (MTF), noise power spectrum, and DQE. Results: For both prototypes, MTF and DQE results were found to be consistent with theoretical expectations and the MTFs were also found to be higher than that measured from a conventional MV AMFPI. In addition, the DQE results exhibit input-quantum-limited behavior, even at extremely low doses. Compared to PVD, the PIB prototype exhibits much lower dark current, slightly higher lag, and similar DQE. Finally, the challenges associated with this approach, as well as strategies for achieving considerably higher DQE through thicker HgI2 layers, are discussed. Conclusions: The DQE of each of the prototypes is found to be comparable to that of conventional MV AMFPIs, commensurate with the modest photoconductor thicknesses of these early samples. It is anticipated that thicker layers of HgI2 based on PIB deposition can provide higher DQE while maintaining good material properties. [ABSTRACT FROM AUTHOR]

A simplified method has been adapted for the extraction and purification of the massive myofibrillar protein titin from the skeletal muscle of sea bream to homogeneity, and a specific polyclonal antibody against titin was generated in rat. The effect of myofibril-bound serine proteinase (MBSP) on the degradation of titin and nebulin from sea bream (Sparus latus Houttuyn) was investigated by sodium dodecyl sulfate polyacrylamide gel electrophoresis and by Western blot. Analysis revealed that both titin and nebulin could be degraded by MBSP, with nebulin degrading faster whether at the optimum temperature of MBSP (55C) and cold storage temperature (4C). These results suggested that MBSP is an important enzyme not only involved in the degradation of myofibrillar proteins such as myosin heavy chain, α-actinin, actin and tropomyosin, but also giant proteins titin and nebulin during the postmortem stage. PRACTICAL APPLICATIONS Titin and nebulin are giant proteins with molecular masses of 3,000 kDa and 600–800 kDa, respectively. Until now, few research concerning the degradation of these two proteins of fish has been reported. In the present study, a simplified method was adapted to purify native titin, and a specific polyclonal antibody against it was prepared. The degradation effect of a myofibril-bound serine proteinase on titin and nebulin at two different temperatures (55C, 4C) was investigated. It is expected that the specific antibody against titin may be used to detect the degradation of titin during the postmortem stage of fish effectively. [ABSTRACT FROM AUTHOR]

Active matrix flat-panel imager (AMFPI) technology is being employed for an increasing variety of imaging applications. An important element in the adoption of this technology has been significant ongoing improvements in optical signal collection achieved through innovations in indirect detection array pixel design. Such improvements have a particularly beneficial effect on performance in applications involving low exposures and/or high spatial frequencies, where detective quantum efficiency is strongly reduced due to the relatively high level of additive electronic noise compared to signal levels of AMFPI devices. In this article, an examination of various signal properties, as determined through measurements and calculations related to novel array designs, is reported in the context of the evolution of AMFPI pixel design. For these studies, dark, optical, and radiation signal measurements were performed on prototype imagers incorporating a variety of increasingly sophisticated array designs, with pixel pitches ranging from 75 to 127 μm. For each design, detailed measurements of fundamental pixel-level properties conducted under radiographic and fluoroscopic operating conditions are reported and the results are compared. A series of 127 μm pitch arrays employing discrete photodiodes culminated in a novel design providing an optical fill factor of ∼80% (thereby assuring improved x-ray sensitivity), and demonstrating low dark current, very low charge trapping and charge release, and a large range of linear signal response. In two of the designs having 75 and 90 μm pitches, a novel continuous photodiode structure was found to provide fill factors that approach the theoretical maximum of 100%. Both sets of novel designs achieved large fill factors by employing architectures in which some, or all of the photodiode structure was elevated above the plane of the pixel addressing transistor. Generally, enhancement of the fill factor in either discrete or continuous photodiode arrays was observed to result in no degradation in MTF due to charge sharing between pixels. While the continuous designs exhibited relatively high levels of charge trapping and release, as well as shorter ranges of linearity, it is possible that these behaviors can be addressed through further refinements to pixel design. Both the continuous and the most recent discrete photodiode designs accommodate more sophisticated pixel circuitry than is present on conventional AMFPIs – such as a pixel clamp circuit, which is demonstrated to limit signal saturation under conditions corresponding to high exposures. It is anticipated that photodiode structures such as the ones reported in this study will enable the development of even more complex pixel circuitry, such as pixel-level amplifiers, that will lead to further significant improvements in imager performance. [ABSTRACT FROM AUTHOR]

Megavoltage cone-beam computed tomography (MV CBCT) is a highly promising technique for providing volumetric patient position information in the radiation treatment room. Such information has the potential to greatly assist in registering the patient to the planned treatment position, helping to ensure accurate delivery of the high energy therapy beam to the tumor volume while sparing the surrounding normal tissues. Presently, CBCT systems using conventional MV active matrix flat-panel imagers (AMFPIs), which are commonly used in portal imaging, require a relatively large amount of dose to create images that are clinically useful. This is due to the fact that the phosphor screen detector employed in conventional MV AMFPIs utilizes only ∼2% of the incident radiation (for a 6 MV x-ray spectrum). Fortunately, thick segmented scintillating detectors can overcome this limitation, and the first prototype imager has demonstrated highly promising performance for projection imaging at low doses. It is therefore of definite interest to examine the potential performance of such thick, segmented scintillating detectors for MV CBCT. In this study, Monte Carlo simulations of radiation energy deposition were used to examine reconstructed images of cylindrical CT contrast phantoms, embedded with tissue-equivalent objects. The phantoms were scanned at 6 MV using segmented detectors having various design parameters (i.e., detector thickness as well as scintillator and septal wall materials). Due to constraints imposed by the nature of this study, the size of the phantoms was limited to ∼6 cm. For such phantoms, the simulation results suggest that a 40 mm thick, segmented CsI detector with low density septal walls can delineate electron density differences of ∼2.3% and 1.3% at doses of 1.54 and 3.08 cGy, respectively. In addition, it was found that segmented detectors with greater thickness, higher density scintillator material, or lower density septal walls exhibit higher contrast-to-noise performance. Finally, the performance of various segmented detectors obtained at a relatively low dose (1.54 cGy) was compared with that of a phosphor screen similar to that employed in conventional MV AMFPIs. This comparison indicates that for a phosphor screen to achieve the same contrast-to-noise performance as the segmented detectors ∼18 to 59 times more dose is required, depending on the configuration of the segmented detectors. [ABSTRACT FROM AUTHOR]

The functional role of neutral lipids in the lung is poorly understood. Lysosomal acid lipase (LAL) is a critical enzyme in hydrolysis of cholesteryl esters and triglycerides to generate free fatty acids and cholesterol in lysosomes. Human LAL was over-expressed in a doxycycline-controlled system in mouse respiratory epithelial cells to accelerate intracellular neutral lipid degradation and perturb the surfactant homeostasis in the lung. In this animal system, neutral lipid concentrations of pulmonary surfactant were reduced in bronchoalveolar lavage fluid (BALF) in association with decrease of surfactant protein C (SP-C) gene expression. The size and the number of lamellar bodies in alveolar type II epithelial cells (AT II cells) were significantly reduced accordingly. The number of macrophages required for surfactant recycling in BALF was also significantly reduced. As a result of these combinatory effects, emphysema of the alveolar structure was observed. Taken together, neutral lipid homeostasis is essential for maintenance of lamellar body genesis and the alveolar structure in the lung. [ABSTRACT FROM AUTHOR]

The M-superfamily of conotoxins has a typical Cys framework (-CC-C-C-CC-), and is one of the eight major superfamilies found in the venom of the cone snail. Depending on the number of residues located in the last Cys loop (between Cys4 and Cys5), the M-superfamily family can be divided into four branches, namely M-1, -2, -3 and -4. Recently, two M-1 branch conotoxins (mr3e and tx3a) have been reported to possess a new disulfide bond arrangement between Cys1 and Cys5, Cys2 and Cys4, and Cys3 and Cys6, which is different from those seen in the M-2 and M-4 branches. Here we report the 3D structure of mr3e determined by 2D 1H NMR in aqueous solution. Twenty converged structures of this peptide were obtained on the basis of 190 distance constraints obtained from NOE connectivities, as well as six ϕ dihedral angle, three hydrogen bond, and three disulfide bond constraints. The rmsd values about the averaged coordinates of the backbone atoms were 0.43 ± 0.19 Å. Although mr3e has the same Cys arrangement as M-2 and M-4 conotoxins, it adopts a distinctive backbone conformation with the overall molecule resembling a ‘flying bird’. Thus, different disulfide linkages may be employed by conotoxins with the same Cys framework to result in a more diversified backbone scaffold. [ABSTRACT FROM AUTHOR]

Empirical and theoretical investigations of the performance of a small-area, high-spatial-resolution, active matrix flat-panel imager, operated under mammographic conditions, is reported. The imager is based on an indirect detection array incorporating a continuous photodiode design, as opposed to the discrete photodiode design employed in conventional flat-panel imagers. Continuous photodiodes offer the prospect of higher fill factors, particularly for arrays with pixel pitches below ∼100 μm. The array has a pixel-to-pixel pitch of 75 μm and a pixel format of 512×512, resulting in an active area of ∼3.8×3.8 cm2. The array was coupled to two commercially available, structured CsI:Tl scintillators of ∼150 μm thickness: one optimized for high light output (FOS-HL) and the other for high spatial resolution (FOS-HR), resulting in a pair of imager configurations. Measurements of sensitivity, modulation transfer function (MTF), noise power spectra (NPS), and detective quantum efficiency (DQE) were performed with a 26 kVp mammography beam at exposures ranging from ∼0.5 to ∼19 mR. MTF results from both CsI:Tl scintillators show that the array demonstrates good spatial resolution, indicating effective isolation between adjacent pixels. The effect of additive noise of the system on DQE was observed to be significantly higher for the FOS-HR scintillator compared to the FOS-HL scintillator due to lower sensitivity of the former. For the FOS-HL scintillator, DQE performance was generally high at high exposures, limited by the x-ray quantum efficiency, Swank factor and the MTF of the scintillators. For both scintillators, the DQE performance degrades at lower exposures due to the relatively large contribution of additive noise. Theoretical calculations based on a cascaded systems model were found to be in general agreement with the empirically determined NPS and DQE values. Finally, such calculations were used to predict potential DQE performance for hypothetical 50 μm pixel pitch imagers, employing similar continuous photodiode design and realistic inputs derived from the empirical measurements. [ABSTRACT FROM AUTHOR]

The transcription factor TFII-I has been shown to bind independently to two distinct promoter elements, a pyrimidine­rich initiator (Inr) and a recognition site (E-box) for upstream stimulatory factor 1 (USF1), and to stimulate USF1 binding to both of these sites. Here we describe the isolation of a cDNA encoding TFII-I and demonstrate that the corresponding 120 kDa polypeptide, when expressed ectopically, is capable of binding to both Inr and E-box elements. The primary structure of TFII-I reveals novel features that include six directly repeated 90 residue motifs that each possess a potential helix­loop/span­helix homology. These unique structural features suggest that TFII-I may have the capacity for multiple protein­protein and, potentially, multiple protein­DNA interactions. Consistent with this hypothesis and with previous in vitro studies, we further demonstrate that ectopic TFII-I and USF1 can act synergistically, and in some cases independently, to activate transcription in vivo through both Inr and the E-box elements of the adenovirus major late promoter. We also describe domains of USF1 that are necessary for its independent and synergistic activation functions. [ABSTRACT FROM AUTHOR]

Multiphase flow hydrodynamics in a novel gas–liquid–solid jet‐loop reactor (JLR) were experimentally investigated at the macroscales and mesoscales. The chord length distribution was measured by an optical fiber probe and transformed for bubble size distribution through the maximum entropy method. The impacts of key operating conditions (superficial gas and liquid velocity, solid loading) on hydrodynamics at different axial and radial locations were comprehensively investigated. JLR was found to have good solid suspension ability owing to the internal circulation of bubbles and liquid flow. The gas holdup, axial liquid velocity, and bubble velocity increase with gas velocity, while liquid velocity has little influence on them. Compared with the gas–liquid JLRs, solids decrease the gas holdup and liquid circulation, reduces the bubble velocity and delays the flow development due to the enhanced interaction between bubbles and particles (Stokes number >1). This work also provides a benchmark data for computational fluid dynamics (CFD) model validation. © 2019 American Institute of Chemical Engineers AIChE J, 65: e16537, 2019 [ABSTRACT FROM AUTHOR]

Studies the allele frequency distributions for nine short tandem repeat loci from a population sample in Tibet, China. Data obtained of relevance to forensic science; Forensic efficiency parameters.

Presents a study which sought to provide a 15 STR database for a population sample of Chinese in Chengdu, China. Obtainment of whole blood specimens by venipuncture; Extraction of DNA using Chelex-100 and proteinase K; Calculation of the forensic efficiency parameters by the Promega Software, POWERSTATS.

NPC2 has been recently identified as the second gene in the autosomal recessive cholesterol storage disorder, the NPC disease. It encodes a secretory, 151 amino acid protein with unknown function. NPCI encodes integral membrane protein that regulates cholesterol content in lipid droplets through mobilization of intracellular cholesterol to the plasma membrane. The NPC1 and NPC2 mutations yield similar clinical phenotypes that are characterized, among the others, by a very short lifespan (11-12 weeks) of NPC-null mice as well as by their significant (∼3-fold) weight loss. The latter circumstance prompted us to investigate a role of NPC2 protein in adipogenesis and adipocyte metabolism. We report here that young, 4-weeks old male and female NPC1-null mice, had already developed characteristic hepatomegaly but displayed normal development and growth of both visceral and subcutaneous fat pads as revealed by immunohistochemistry. However, the siRNA silencing of NPC2 gene in adult primary human adipocytes resulted in dramatic (∼ 2-fold) reduction in their triacylglycerol pool due to activated lipolysis. The latter process was accompanied by inhibition of fatty acid transport (∼3.5-fold) and stimulation of insulin-independent, GLUT1-dependent glucose uptake (∼2-fold). These results identify NPC2 protein as a novel adipokine that promotes adipocyte fat accumulation and insulin sensitivity. [ABSTRACT FROM AUTHOR]