Search

Current–voltage characteristics and low-frequency (LF) noise of industrial-quality AlGaAs/InGaAs/GaAs pseudomorphic high-electron-mobility transistors are evaluated as a function of bias stress and temperature. A small positive shift of threshold voltage Vth and negligible degradation in peak transconductance GM are observed under ON-state bias conditions at elevated temperatures. The Vth measurements suggest activation of an acceptor-like defect or impurity center. The GM measurements demonstrate that newly activated defects are not located close enough to the two-dimensional electron gas to scatter carriers strongly. First-principles calculations and comparisons with previous work suggest that OAs impurity centers, other oxygen-related defects, isolated AsGa antisites, and dopant-based DX centers may contribute significantly to low-frequency (LF) noise in as-processed devices. LF noise is relatively unaffected by voltage stress at elevated temperatures, consistent with the small changes in Vth and peak GM. [ABSTRACT FROM AUTHOR]

Low-frequency (LF) noise measurements are compared for Schottky-gate AlGaN/GaN heterostructure planar and fin field-effect transistors (FinFETs) as functions of gate voltage and measuring temperature. The noise of each device type is consistent with a carrier number fluctuation model. Similar effective defect-energy Eo distributions are derived for each of the two device architectures from measurements of excess drain-voltage noise-power spectral density vs temperature from 80 to 380 K. Defect- and/or impurity-related peaks are observed in the inferred energy distributions for Eo < 0.2 eV, Eo ≈ 0.45 eV, and Eo > 0.6 eV. Significant contributions to the LF noise are inferred for nitrogen vacancies and ON and FeGa impurity complexes. Ga dangling bonds at fin interfaces with gate metal are likely candidates for enhanced noise observed in FinFETs, relative to planar devices. Reducing the concentrations of these defects and impurity complexes should reduce the LF noise and enhance the performance, reliability, and radiation tolerance of GaN-based high electron mobility transistors. [ABSTRACT FROM AUTHOR]

The growth and remodelling of soft tissues plays a significant role in many physiological applications, particularly in understanding and managing many diseases. A commonly used approach for soft tissue growth and remodelling is volumetric growth theory, introduced in the framework of finite elasticity. In such an approach, the total deformation gradient tensor is decomposed so that the elastic and growth tensors can be studied separately. A critical element in this approach is to determine the growth tensor and its evolution with time. Most existing volumetric growth theories define the growth tensor in the reference (natural) configuration, which does not reflect the continuous adaptation processes of soft tissues under the current configuration. In a few studies where growth from a loaded configuration was considered, simplifying assumptions, such as compatible deformation or geometric symmetries, were introduced. In this work, we propose a new volumetric growth law that depends on fields evaluated in the current configuration, which is residually stressed and loaded, without any geometrical restrictions. We illustrate our idea using a simplified left ventricle model, which admits inhomogeneous growth in the current configuration. We compare the residual stress distribution of our approach with the traditional volumetric growth theory, that assumes growth occurring from the natural reference configuration. We show that the proposed framework leads to qualitative agreements with experimental measurements. Furthermore, using a cylindrical model, we find an incompatibility index that explains the differences between the two approaches in more depth. We also demonstrate that results from both approaches reach the same steady solution published previously at the limit of a saturated growth. Although we used a left ventricle model as an example, our theory is applicable in modelling the volumetric growth of general soft tissues. [ABSTRACT FROM AUTHOR]

We introduce a mathematical model for the mechanical behaviour of the eukaryotic cell cytoskeleton. This discrete model involves a regular array of pre-stressed protein filaments that exhibit resistance to enthalpic stretching, joined at cross-links to form a network. Assuming that the inter-cross-link distance is much shorter than the length scale of the cell, we upscale the discrete force balance to form a continuum system of governing equations and deduce the corresponding macroscopic stress tensor. We use these discrete and continuum models to analyse the imposed displacement of a bead placed in the domain, characterizing the cell rheology through the force–displacement curve. We further derive an analytical approximation to the stress and strain fields in the limit of small bead radius, predicting the net force required to generate a given deformation and elucidating the dependency on the microscale properties of the filaments. We apply these models to networks of the intermediate filament vimentin and demonstrate good agreement between predictions of the discrete, continuum and analytical approaches. In particular, our model predicts that the network stiffness increases sublinearly with the filament pre-stress and scales logarithmically with the bead size. [ABSTRACT FROM AUTHOR]

Anemia is a common hematologic abnormality in systemic lupus erythematosus (SLE). An inadequate erythropoietin (EPO) response in SLE patients with anemia has been described that may be due to the presence of antibodies to EPO in SLE patients. However, whether anemia in patients with SLE is related to antibodies to EPO receptor (EPOR) has not yet been investigated. We enlisted 169 consecutive patients with SLE and 45 normal individuals to investigate the existence and importance of circulating autoantibodies to EPOR in sera from patients with SLE. In all patients with SLE, the disease activity was evaluated by using the SLE disease activity index SLEDAI. Anti-EPOR antibodies were detected by using an enzyme-linked immunosorbent assay (ELISA). A higher frequency of anti-EPOR antibodies was observed in SLE patients than in healthy controls (18.3% vs 2.2%, p = 0.007). Moreover, anti-EPOR antibodies were detected in 22 of 69 (31.9%) SLE patients with anemia and in only nine of 100 (9.0%, p < 0.001) in those without. Furthermore, the patients with anti-EPOR antibodies exhibited more severe anemia and often presented as microcytic anemia (p = 0.001). Finally, anti-EPOR antibodies seemed more likely to occur in patients with rash (p = 0.008), lower levels of C3 component (p = 0.01), higher titer of anti-dsDNA antibodies (p < 0.001) and higher disease activity scores (p = 0.024). The results of this study suggest that anti-EPOR antibodies might play a vital role in SLE patients developing anemia because of the higher incidence of antibodies to EPOR found in SLE patients with anemia. Thus, there might be clinical value in detecting anti-EPOR antibodies in SLE patients with anemia. Therefore, the pathologic role of the antibodies in inducing anemia needs to be established in future studies. [ABSTRACT FROM AUTHOR]

Estimation of biomechanical parameters of soft tissues from noninvasive measurements has clinical significance in patient-specific modeling and disease diagnosis. In this work, we present a quasi-nonlinear method that is used to estimate the elastic moduli of the human gallbladder wall. A forward approach based on a transversely isotropic membrane material model is used, and an inverse iteration is carried out to determine the elastic moduli in the circumferential and longitudinal directions between two successive ultrasound images of gallbladder. The results demonstrate that the human gallbladder behaves in an anisotropic manner, and constitutive models need to incorporate this. The estimated moduli are also nonlinear and patient dependent. Importantly, the peak stress predicted here differs from the earlier estimate from linear membrane theory. As the peak stress inside the gallbladder wall has been found to strongly correlate with acalculous gallbladder pain, reliable mechanical modeling fop" gallbladder tissue is crucial if this information is to be used in clinical diagnosis. [ABSTRACT FROM AUTHOR]

CXCL12, also known as stromal cell-derived factor (SDF-1), is a CXC chemokine. Recent reports have shown that CXCL12 might play key roles in a murine model of lupus and in patients with systemic lupus erythematosus (SLE). A common variant at position 801 in 3′-untranslated region in CXCL12 gene (designated CXCL12-3′G801A) has been reported in association with autoimmune diseases, such as type 1 diabetes and systemic sclerosis. We investigated the influence of CXCL12-3′G801A polymorphism on susceptibility to SLE by genotyping this single nucleotide polymorphism in 422 SLE patients and 374 healthy controls. The frequency of G/G homozygote was observed in 60.0% of SLE patients and in 52.7% of healthy individuals (χ2 = 4.275, p = 0.039). Compared with patients with G/A and A/A genotype, SLE patients with G/G genotype were also more prone to developing photosensitivity (χ2 = 6.778, p = 0.034), renal damage (χ2 = 6.388, p = 0.041) and to producing antibodies against nucleosomes (χ2 = 8.341, p = 0.015). Moreover, the plasma level of CXCL12α was also significantly increased in patients with G/G homozygote than in healthy controls carrying the same genotype [(4067.0 ± 1092.3) pg/ml vs. (3278.5 ± 547.4) pg/ml, p = 0.002]. Our results suggest that polymorphism in CXCL12-3′G801A might be a genetic risk factor for developing SLE. The association of G/G homozygote with nephritis and skin damage developed in SLE patients might be due to its effects upon the production of auto-antibodies and CXCL12 protein. [ABSTRACT FROM AUTHOR]

The vitamin D receptor (VDR) gene is a candidate gene for susceptibility to autoimmune disorders. Association studies of VDR polymorphisms and risk of systemic lupus erythematosus (SLE) have often produced conflicting results in different ethnic backgrounds. The aim of this study is to test the association between VDR gene BsmI polymorphism and the genetic susceptibility to SLE in a Han Chinese population.Three hundred and thirty-seven patients with SLE and 239 healthy controls were genotyped for the VDR gene BsmI polymorphism (rs1544410) by polymerase chain reaction and restriction fragment length polymorphism analysis in this study, after which the relationship between BsmI polymorphisms and the mRNA expression of VDR, as well as clinical manifestations in patients with SLE, was evaluated.It was found that the frequency of B allele was significantly increased in SLE relative to the control group (χ2 = 4.681, p = 0.031), although the distribution of VDR BsmI polymorphism genotype frequencies did not differ significantly between patients and controls (χ2 = 4.098, p = 0.129). Moreover, VDR B allele was found to be associated with lupus nephritis (p = 0.027) and also with production of anti-nucleosome antibodies (p = 0.037). The mRNA of VDR was markedly down-regulated in patients with VDR B allele compared with that in patients without B allele (p = 0.016).Our results indicate a possible role of genetic factors (the VDR B allele) in influencing disease susceptibility in Han Chinese patients. Also, VDR B allele is associated with the development of nephritis and the down-regulation of VDR mRNA expression in SLE. [ABSTRACT FROM AUTHOR]

Yuan, L. G., Luo, X. Y., Zhu, L. X., Wang, R., Liu, Y. H. A physiologically based pharmacokinetic model for valnemulin in rats and extrapolation to pigs. J. vet. Pharmacol. Therap., 224-231. A flow-limited, physiologically based pharmacokinetic (PBPK) model for predicting the plasma and tissue concentrations of valnemulin after a single oral administration to rats was developed, and then the data were extrapolated to pigs so as to predict withdrawal interval in edible tissues. Blood/tissue pharmacokinetic data and blood/tissue partition coefficients for valnemulin in rats and pigs were collected experimentally. Absorption, distribution and elimination of the drug were characterized by a set of mass-balance equations. Model simulations were achieved using a commercially available software program. The rat PBPK model better predicted plasma and tissue concentrations. The correlation coefficients of the predicted and experimentally determined values for plasma, liver, kidney, lung and muscle were 0.96, 0.94, 0.96, 0.91 and 0.91, respectively. The rat model parameters were extrapolated to pigs to estimate valnemulin residue withdrawal interval in edible tissues. Correlation ( R) between predicted and observed liver, kidney and muscle were 0.95, 0.97 and 0.99, respectively. Based on liver tissue residue profiles, the pig model estimated a withdrawal interval of 10 h under a multiple oral dosing schedule (5.0 mg/kg, twice daily for 7.5 days). PBPK models, such as this one, provide evidence of the usefulness in interspecies PK data extrapolation over a range of dosing scenarios and can be used to predict withdrawal interval in pigs. [ABSTRACT FROM AUTHOR]

Transport and deposition of aerosol particles in a plane channel with a ribbed wall are studied in order to investigate the effects of the turbulent flow structure on particle deposition. In this paper, kinematic simulation (KS) has been adapted to be a sub-grid model for particles, in conjunction with large eddy simulation (LES) in real space with boundaries. KS is a Lagrangian model of turbulent dispersion that takes into account the effects of spatio-temporal flow structure on particle dispersion. It is a unified Lagrangian model of one-, two- and indeed multi-particle turbulent dispersion and can easily be used as a Lagrangian sub-grid model for LES codes, thus enabling complex geometry to be taken into account. To study the effect of small-scale flow structures on particle deposition in the ribbed channel flow, we use a validated LES code to simulate the flow field, and KS to model the sub-grid flow structures. Thus, the large scales are resolved by the simulation and the small scales are modelled using various sub-grid models. As none of the existing sub-grid models is known to have taken into account the effects of small-scale turbulent flow structures on particle deposition, it is important to use KS's ability to remodel the sub-grid velocity field and thereby incorporate its effect on particle deposition. The parameters of our simulations for LES are the Reynolds number, width of the channel, height of the rib and sub-gridmodel parameters. For KS, the parameters are the energy dissipation rate obtained from LES, the energy spectra, ratio of the largest and smallest sub-grid scales and the total number of modes for the sub-grid velocity field. The turbulent flow features thus obtained are compared with published experimental data in a ribbed channel. Our results suggest that while the small-scale (sub-grid) turbulent flow structures have negligible effects on particles with large relaxation times (compared with the Kolmogorov dissipation time scale), deposition of the particles with small relaxation times in the ribbed channel can be affected by these sub-grids. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

An Immersed Boundary fluid-structure interaction model is developed to investigate the dynamic behaviour of a prosthetic chorded mitral valve (MV) inside the left ventricle (LV). In order to simulate more realistic physiological flow conditions, in vivo magnetic resonance images of the LV are used to determine the anatomical structure and the motion of the LV. The LV geometry and its motion are incorporated into the dynamic MV model. This model allows us to investigate the influences of the flow vortex generated by the LV motion on the MV dynamics, as well as the impact of the motion of the chordae attachment points (CAPs). Results are compared with two other cases: (i) an LV model with no prescribed motion of the CAPs, (ii) a Tube model in which the LV is replaced by a tube, although the motion of the chordae is incorporated. These special cases enable the influence of the chordae motion and the vortex on the behaviour of the MV to be analysed independently. It is found that when the MV is placed inside a dynamic LV, the chordae and the valve stretch are significantly increased in the commissural region, and the flow field is strongly asymmetric, with a clockwise single vortex appearing after the early rapid filling phase of the diastole. Given that we impose a flow rate boundary condition, the reverse pressure gradient cannot be established and, hence, the valve does not close properly. Clearly, the presence of the flow vortex alone is not strong enough to aid the valve closure. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

We investigate the influences of modelling assumptions on the dynamic behaviour of collapsible channel flows. The elastic wall is modelled in various different ways: as a large strain Bernoulli–Euler beam, as a small strain Timoshenko beam, and as a 2D-solid model derived from a general virtual work approach, using small strain or large strain assumptions. Different inlet boundary conditions are also considered. The in-house finite element codes and the commercial finite element package ADINA 8.4 are used. The steady results agree very well when using the different models/approaches. The unsteady results, on the other hand, can be quite different. The dynamic behaviour of the system is analysed for a set of chosen parameters, using the full numerical solvers, the linear stability analysis, and the Fourier transform. It is found that the system stability is highly sensitive to the solid modelling assumptions used, numerical solvers adopted, or the boundary conditions imposed. Accuracy of the numerical schemes also has an impact on the system's unsteady behaviour. However, despite the high sensitivity of the unsteady solutions to the modelling assumptions, a cascade stability structure previously revealed by the authors seems to exist when different numerical approaches are used. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Acalculous biliary pain occurs in patients with no gallstones, but is similar to that experienced by patients with gallstones. Surgical removal of the gallbladder (GB) in these patients is only successful in providing relief of symptoms to about half of those operated on, so a reliable pain-prediction model is needed. In this paper, a mechanical model is developed for the human biliary system during the emptying phase, based on a clinical test in which GB volume changes are measured in response to a standard stimulus and a recorded pain profile. The model can describe the bile emptying behaviour, the flow resistance in the biliary ducts, the peak total stress, including the passive and active stresses experienced by the GB during emptying. This model is used to explore the potential link between GB pain and mechanical factors. It is found that the peak total normal stress may be used as an effective pain indicator for GB pain. When this model is applied to clinical data of volume changes due to Cholecystokinin stimulation and pain from 37 patients, it shows a promising success rate of 88.2% in positive pain prediction. [ABSTRACT FROM AUTHOR]

Abstract: Numerical simulation of multi-phase flow is essential to evaluate the feasibility of a liquid protection scheme for the power plant chamber. The level set method is one of the best methods for computing and analyzing the motion of interface among the multi-phase flow. This paper presents a general formula for the second-order projection method combined with the level set method to simulate unsteady incompressible multi-phase flow with/out phase change flow encountered in fusion science and engineering. The third-order ENO scheme and second-order semi-implicit Crank–Nicholson scheme is used to update the convective and diffusion term. The numerical results show this method can handle the complex deformation of the interface and the effect of liquid–vapor phase change will be included in the future work. [Copyright &y& Elsevier]

A novel quality metric for image fusion using saliency-based geometry measurement is presented. The method provides a quantification of salient structural information transferred from each source into the fused image. Viewing the multiple measures as a point for an image fusion technique, the final fusion performance is evaluated via computing how far the distance is from the result point to an ideal point with perfect value in each source quantification dimension. Experimental results indicate that the proposed metric outperforms other popular performance assessment methods for image fusion. [ABSTRACT FROM PUBLISHER]

Nine papers in the area of ‘Flow in collapsible tubes or over compliant surfaces for biomedical applications’ are collated and presented in this special issue. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Amid advancements in information technology, this study explores the integration of blockchain technology in supply chain management, particularly for improving collaborative production mechanisms. Known for decentralization, transparency, and data security, blockchain is seen as a solution for issues like information delays and asymmetry in traditional supply chains. To address a gap in empirical research, a model incorporating blockchain for information collaboration in supply chain production management was developed using the Stackelberg game model. Furthermore, a consensus decision model aimed at enhancing supply chain collaboration was established within the blockchain network. These findings provide valuable insights into the practical benefits of blockchain in supply chain management, offering direction for future practice. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented referring to the case study of a boy suffering from Naevus of Ota along with vitiligo.

The article presents a call for original papers and articles related to flow in collapsible channels and tubes, external and internal flows past compliant boundaries, instabilities of flows in or over compliant surfaces, and biological applications.

This paper studies two one-dimensional models to estimate the pressure drop in the normal human biliary system for Reynolds number up to 20. Excessive pressure drop during bile emptying and refilling may result in incomplete bile emptying, leading to stasis and subsequent formation of gallbladder stones. The models were developed following the group's previous work on the cystic duct using numerical simulations. Using these models, the effects of the biliary system geometry, elastic property of the cystic duct, and bile viscosity on the pressure drop can be studied more efficiently than with full numerical approaches. It was found that the maximum pressure drop occurs during bile emptying immediately after a meal, and is greatly influenced by the viscosity of the bile and the geometric configuration of the cystic duct, i.e., patients with more viscous bile or with a cystic duct containing more baffles or a longer length, have the greatest pressure drop. It is found that the most significant parameter is the diameter of the cystic duct; a 1% decrease in the diameter increases the pressure drop by up to 4.3%. The effects of the baffle height ratio and number of baffles on the pressure drop are reflected in the fact that these effectively change the equivalent diameter and length of the cystic duct. The effect of the Young's modulus on the pressure drop is important only if it is lower than 400 Pa; above this value, a rigid-walled model gives a good estimate of the pressure drop in the system for the parameters studied. [ABSTRACT FROM AUTHOR]

SUMMARY Finite strain analyses of the left ventricle provide important information on heart function and have the potential to provide insights into the biomechanics of myocardial contractility in health and disease. Systolic dysfunction is the most common cause of heart failure; however, abnormalities of diastolic function also contribute to heart failure, and are associated with conditions including left ventricular hypertrophy and diabetes. The clinical significance of diastolic abnormalities is less well understood than systolic dysfunction, and specific treatments are presently lacking. To obtain qualitative and quantitative information on heart function in diastole, we develop a three-dimensional computational model of the human left ventricle that is derived from noninvasive imaging data. This anatomically realistic model has a rule-based fibre structure and a structure-based constitutive model. We investigate the sensitivity of this comprehensive model to small changes in the constitutive parameters and to changes in the fibre distribution. We make extensive comparisons between this model and similar models that employ different constitutive models, and we demonstrate qualitative and quantitative differences in stress and strain distributions for the different constitutive models. We also provide an initial validation of our model through comparisons to experimental data on stress and strain distributions in the left ventricle. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The problem of tracking control for a class of uncertain time-delay non-linear system with state constraint is addressed. To prevent constraint violation, the tangent barrier Lyapunov function (TBLF) is firstly used for time-delay nonlinear system. By ensuring boundedness of the TBLF in the closed loop, besides those limits are not transgressed, the authors also tackle scenarios wherein parametric uncertainties and time delays are presented. Asymptotically tracking stable in the sense of uniformly ultimate boundedness is achieved without violation of the constraint. Finally, the performance of the proposed control has been illustrated through a chaotic system. [ABSTRACT FROM AUTHOR]

Three-dimensional scaled-up transparent models of three human cystic ducts were prepared on the basis of anatomical specimens. The measurement of pressure drop across the cystic duct models and visualization of the flow structures within these ducts were peiformed at conditions replicating the physiological state. The flow visualization study confirmed the laminar nature of the flow of bile inside the cystic duct and values of pressure drop coefficient (Cp) decreased as the Reynolds number (Re) increased. The three tested models showed comparable behavior for the curve of Reynolds number versus the pressure drop coefficient. The results show that the tested cystic ducts have both increased pressure drop and complicated flow structures when compared with straight conduits. High resistance in a cystic duct may indicate that the gallbladder has to exert large force in expelling bile to the cystic duct. For patients with diseased gallbladder and even in healthy persons, gallbladder is known to stiffen with age and it may lose its compliance or flexibility. A high resistance cystic duct coupled with a stiffened gallbladder may result in prolonged stasis of bile in the gallbladder which is assumed to encourage the formation of gallstones. [ABSTRACT FROM AUTHOR]

HLA-G is a non-classical HLA-class Ib molecule with multiple immunoregulatory properties. A 14-bp insertion/deletion polymorphism in the HLA-G gene has been suggested to influence the expression of HLA-G and to associate with certain pathological conditions, including autoimmune diseases. We investigated the influence of the 14-bp insertion/deletion polymorphism in the HLA-G gene on disease susceptibility in systemic lupus erythematosus by genotyping this polymorphism in 231 patients with systemic lupus erythematosus and 367 healthy controls and analyzing the levels of soluble HLA-G in a subset of patients with systemic lupus erythematosus and healthy subjects from a Han Chinese population. No statistically significant differences were observed in the frequencies of the 14-bp insertion/deletion HLA-G alleles or genotypes between controls and patients with systemic lupus erythematosus. However, a significant increased expression of soluble HLA-G was noted in patients with systemic lupus erythematosus (mean value=230.2U/ml vs 118.3U/ml in controls, p=0.0001). Moreover, patients with high levels of soluble HLA-G presented with higher disease activity and had more neurological involvement. Our results do not support the HLA-G 14-bp insertion/deletion polymorphism as a genetic factor influencing systemic lupus erythematosus susceptibility. It is possible that the expression of soluble HLA-G in systemic lupus erythematosus is enhanced as part of a mechanism to try to restore the tolerance process towards auto-antigens and to counteract inflammation. However, the participation of this molecule in the pathological process of the disease also could not be excluded. [ABSTRACT FROM AUTHOR]

Although little is known about the transport mechanism of bile in the human biliary system, clinical studies suggest that it may be a contributing factor in the pathogenesis of cholelithiasis. This paper reports an investigation of the steady flow in two-dimensional human biliary system models using flow visualization. The geometries of these two-dimensional models were described based on actual patients' operative cholangiograms. Two models were used: one represented biliary system of a patient suffering from gallstones, while the second represented the biliary system of a healthy person. The streamlines of the flow in the cystic duct of the patient suffering from gallstones were highly winding, compared with those of the healthy person. This is an indication of a higher resistance to the flow in the cystic duct of the gallstone patient, which is a contributing factor of the formation of gallstones. The work presented here is a part of an ongoing project aimed at understanding the functions of human cystic duct and the role of bile flow in the formation of gallstones. [ABSTRACT FROM AUTHOR]

To estimate the valnemulin pharmacokinetic profile in a swine population and to assess a dosage regimen for increasing the likelihood of optimization. This study was, respectively, performed in 22 sows culled by p.o. administration and in 80 growing-finishing pigs by i.v. administration at a single dose of 10 mg/kg to develop a population pharmacokinetic model and Monte Carlo simulation. The relationships among the plasma concentration, dose, and time of valnemulin in pigs were illustrated as C i, v = X0(8.4191 × 10-4 × e−0.2371 t + 1.2788 × 10−5 × e−0.0069 t) after i.v. and C p. o = X0(−8.4964 × 10−4 × e−0.5840 t + 8.4195 × e−0.2371 t + 7.6869 × 10−6 × e−0.0069 t) after p.o. Monte Carlo simulation showed that T> MIC was more than 24 h when a single daily dosage at 13.5 mg/kg BW in pigs was administrated by p.o., and MIC was 0.031 mg/L. It was concluded that the current dosage regimen at 10-12 mg/kg BW led to valnemulin underexposure if the MIC was more than 0.031 mg/L and could increase the risk of treatment failure and/or drug resistance. [ABSTRACT FROM AUTHOR]

Aims: A significant association between radioiodine therapy (RIT) and the development or the worsening of pre-existing Graves' ophthalmopathy (GO) has been reported. This post-hoc analysis of 2 studies attempted to describe the changes observed in pre-existing or new-onset GO following RIT with the goal of euthyroidism rather than hypothyroidism and to describe the relationship GO changes and the final outcome. Patients and Methods: In 2 prospective, randomized open-label blinded endpoint trials, patients received radioiodine alone; or, patients received radioiodine or antithyroid drug therapy (ATD). The severity and activity of GO were assessed during a 9-12-year follow-up. The study end points in study 1 were euthyroidism, hyperthyroidism, hypothyroidism, and changes in GO. In study 2, the end points were euthyroidism, hyperthyroidism, hypothyroidism, relapse, and changes in GO. Results: Both RIT and ATD were associated with worsening GO and new-onset GO. Both RIT and ATD led to similar aggravation of pre-existing GO or the development to new-onset GO. After RIT or ATD, the euthyroid patients (without levothyroxine substitution) demonstrated an improvement in GO, with 78-89 % patients with preexisting GO exhibiting improvement, whereas hyperthyroid, hypothyroid and relapsed patients had worsening or new-onset GO. Conclusions: Thyroid function is a dominant risk factor. Thyroid function may be the most important determinant in worsening or newonset GO in both the natural disease course and in treated patients, independent of the kind of treatment. Therefore, we recommend euthyroidism as a goal of treatment. [ABSTRACT FROM AUTHOR]

Background and Purpose A series of benzothiazole derivatives were screened for immunosuppressive activity; of these compounds BD750 was found to be the most effective immunosuppressant. The purpose of the current study was to determine the immunosuppressive activity of BD750 on T cell proliferation and its potential mode of action. Experimental Approach T cell proliferation, CD25 and CD69 expression and cell cycle distribution were measured in vitro by flow cytometry. Cell viability was determined by CCK-8 assay. Cytokine levels were measured by elisa. The activation of signal-regulated molecules was assessed by Western blot analysis. The effects of BD750 were evaluated in vivo in a mouse model of delayed-type hypersensitivity. Key Results BD750 significantly inhibited mouse and human T cell proliferation, stimulated either by anti- CD3/anti- CD28 monoclonal antibodies or by an alloantigen, in a dose-dependent manner in vitro. No obvious cytotoxic effects of BD750 were observed in our experimental conditions. Furthermore, BD750 did not inhibit CD25 and CD69 expression or IL-2 and IL-4 secretion, but induced cell cycle arrest at the G0/ G1 phase in activated T cells. In IL-2-stimulated CTLL-2 cells and primary activated T cells, BD750 inhibited cell proliferation and STAT5 phosphorylation, but not Akt or p70S6 K phosphorylation. BD750 also reduced the T cell-mediated delayed-type hypersensitivity response in mice in a dose-dependent manner. Conclusion and Implications These data indicate that BD750 inhibits IL-2-induced JAK3/ STAT5-dependent T cell proliferation. BD750 has the potential to be used as a lead compound for the design and development of new immunosuppressants for preventing graft rejection and treating autoimmune diseases. [ABSTRACT FROM AUTHOR]

Wang, R., Yuan, L.G., He, L.M., Zhu, L.X., Luo, X.Y., Zhang, C.Y., Yu, J.J., Fang, B.H., Liu, Y.H. Pharmacokinetics and bioavailability of valnemulin in broiler chickens. J. vet. Pharmacol. Therap., 247-251. The objective of this study was to investigate the pharmacokinetics and bioavailability of valnemulin in broiler chickens after intravenous (i.v.), intramuscular (i.m.) and oral administrations of 10 mg/kg body weight (bw). Plasma samples were analyzed by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Pharmacokinetic characterization was performed by non-compartmental analysis using WinNonlin program. After intravenous administration, distribution was wide with the volume of distribution based on terminal phase(V) of 4.27 ± 0.99 L /kg. Mean valnemulin t(h), Cl(L /h /kg), V (L /kg) and AUC(μg·h /mL) values were 2.85, 0.99, 2.72 and 10.34, respectively. After intramuscular administration, valnemulin was rapidly absorbed with a C of 2.2 μg/mL achieved at 0.43 h (t), and the absolute bioavailability (F) was 88.81%; and for the oral route the same parameters were 0.66 ± 0.15 μg/mL, 1.54 ± 0.27 h and 74.42%. A multiple-peak phenomenon was present after oral administration. The plasma profile of valnemulin exhibited a secondary peak during 2-6 h and a tertiary peak at 32 h. The favorable PK behavior, such as the wide distribution, slow elimination and acceptable bioavailability indicated that it is likely to be effective in chickens. [ABSTRACT FROM AUTHOR]

The article presents a study on the pharmacokinetic characteristics of the fluoroquinolone Marbofloxacin administered via various drug routes to Muscovy ducks. The study assessed 30 healthy Muscovy ducks divided into three groups of 10 in a controlled environment, which were then examined using a parallel study design. Results showed that an oral dosage of 2.5 milligrams (mg) per kilogram (kg) is the treatment recommended for infections caused by Gram-negative bacteria in ducks.

The structural and morphological evolution of cobalt-tin (Co--Sn) metal composite oxides, synthesized by the decomposition of CoSn(OH)6 precursor at various temperatures, were investigated by X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM). The precursor was also studied by thermal analysis (TG/DTA). The electrochemical performance of nanosized Co--Sn composite metal oxides was investigated to evaluate their suitability for use as anode materials for Li ion batteries. The results revealed that the samples heat-treated at low temperatures consisted of amorphous CoSnO3, and the samples heat-treated at high temperatures comprised crystalline Co2SnO4 and SnO2. The charge capacity and cyclability were sensitive to the structure and composition of the electrode active materials. The samples heat-treated in the phase transition temperature range exhibited relatively worse electrochemical properties. [ABSTRACT FROM AUTHOR]

The structural and morphological evolution of cobalt-tin (Co-Sn) metal composite oxides, synthesized by the decomposition of CoSn(OH)6 precursor at various temperatures, were investigated by X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM). The precursor was also studied by thermal analysis (TG/DTA). The electrochemical performance of nanosized Co-Sn composite metal oxides was investigated to evaluate their suitability for use as anode materials for Li ion batteries. The results revealed that the samples heat-treated at low temperatures consisted of amorphous CoSnO3, and the samples heat-treated at high temperatures comprised crystalline Co2SnO4 and SnO2. The charge capacity and cyclability were sensitive to the structure and composition of the electrode active materials. The samples heat-treated in the phase transition temperature range exhibited relatively worse electrochemical properties. [ABSTRACT FROM AUTHOR]

Studies the visualization of mixing of flow in circular tubes with segmental baffles. Fluid devices with flow of liquids in circular tubes with segmental baffles; Laminar flow visualized by Fluorescent dye; enhance mixing of the fluid downstream of the pipe.

Microstructures of phosphorus-doped hydrogenated microcrystalline silicon (μc-Si:H) thin films deposited by plasma-enhanced chemical vapor deposition are certainly dependent on the thickness of the H2 plasma-treated amorphous silicon (a-Si:H) layers. An ultrathin H-treated a-Si:H layer is beneficial in obtaining a very thin μc-Si:H film with high conductivity. Experimental results indicate that H2 plasma treatment induces the occurrence of high-pressure H2 in microvoids and causes compressive stress inside the ultrathin a-Si:H layers, thereby enhancing the generation of strained Si-Si bonds and nucleation sites and consequently accelerating the nucleation of μc-Si:H films. [ABSTRACT FROM AUTHOR]