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Feature mode decomposition (FMD) has advantages over the other newer time-frequency methods such as ensemble empirical mode decomposition (EEMD) and variational mode decomposition (VMD) in single channel blind source separation (SCBSS). However, FMD has the defect of needing to determine the precise number of fault sources manually. To solve the above defect of FMD, an adaptive method for determining the number of fault sources based on the shift invariant sparse code (SISC) is proposed. SISC was used to train a set of basis functions from the single channel signal, and the corresponding potential components were reconstructed firstly. Subsequently, the structural similarity of these potential components was used for clustering, and each of the obtained clustering signals represented one kind of fault. Then the number of clustering was determined by minimizing the structural correlation among the clustering signals. It was considered that the source separation had achieved the best effect when the structural difference among the clusters was the largest, and the number of clustering at this time was used as the optimal estimated value, which was used as the modal inputs number of FMD calculation model to realize SCBSS of rolling bearing. Simulation and experimental analysis were carried out to verify the effectiveness of the proposed method, and its superiority was also verified through comparison. [ABSTRACT FROM AUTHOR]

Due to a large number of components, complex meshing relations and high requirements for assembly accuracy, the dynamic characteristic of compound planetary gear, such as vibration, impact, periodic motion and load sharing, are more easily affected by internal excitation than those of simple planetary gear set and parallel shafting gear set. To improve the load sharing behavior and the resistance of Chaos motions in the compound planetary gear set, in this work, by introducing the floating support into the center gear and planet gear, a lumpedparameter dynamic model of the compound planetary gear set is built based on the lumped parameter method and Lagrange kinematics equation. The steady response is calculated by numeric method to investigate the influence of floating support from different components on loading sharing behavior and periodic motion. The results indicate that, the increase of the floating value of all components improves the instantaneous load-sharing behavior, and single floating of planet gear reduces the load sharing behavior. To avoid the system being in quasi-periodic motion and Chaos motions under the condition of floating support, the input speed should be avoided away from the range of 3201 r/min-5069 r/min. [ABSTRACT FROM AUTHOR]

Colon adenocarcinoma (COAD) stands out as the most prevalent malignancy diagnosed within the gastrointestinal tract, bearing substantial incidence and mortality rates. The processes of ageing and senescence intricately intertwine with tumorigenesis and immune regulation, concurrently exerting influence on the remodelling of the tumor microenvironment (TME). This phenomenon, in turn, significantly impacts the efficacy of immunotherapeutic interventions. Despite this awareness, the comprehensive understanding of the intricate interplay between cellular senescence and TME in the context of COAD remains elusive. Further inquiry is imperative to comprehensively gauge the relevance of cellular senescence-related genes (CSGs) in the realms of immune infiltration and the prognostication of COAD. Differentially expressed cell senescence-related genes (DE-CSGs) within COAD tumors and normal specimens were discerned through analysis of the TCGA-COAD dataset. Leveraging univariate, LASSO, and multivariate Cox regression analyses, we formulated a prognostic risk signature. Subsequent validation utilised two independent GEO datasets. Furthermore, a nomogram was devised to gauge the prognostic significance of this signature. Additionally, the immune landscape of the Cell Senescence-related Signature (CSS) was characterised using CIBERSORT and TIMER algorithms. The expression levels of CSGs were quantified through RT-PCR in COAD specimens. Drawing upon mRNA expression profiles of 191 DE-CSGs, we successfully established a 9-gene CSS, demonstrating its autonomy as a prognostic determinant for COAD patients. Those assigned high-risk scores exhibited an immunosuppressive phenotype, marked by elevated proportions of resting CD4+memory T cells and macrophages M0, correlating with diminished overall survival. Subsequent analyses uncovered that the amalgamation of CSS with the expression profiles of immune checkpoint key genes effectively predicted patient prognosis. Furthermore, patients with low-risk scores demonstrated a potential association with more favourable therapeutic outcomes in the context of immunotherapy. This study has culminated in the development of a prognostic risk signature grounded in cell senescence-related genes for COAD. We posit that the CSS plays a regulatory role in immune infiltration, emerging as a robust biomarker for prognosis and a predictive indicator for immunotherapeutic responsiveness within the COAD landscape. [ABSTRACT FROM AUTHOR]

Under tooth profile wear condition, with running time increasing, the tooth chord length of the gear tooth is thinner and the tooth profile is not involute profile any more, which results in the changes in amplitude and fluctuation of time-varying meshing stiffness. In this work, in order to reveal the influence of tooth profile wear on time-varying meshing stiffness, an analytical model for calculating the time-varying meshing stiffness under tooth wear condition is built and incorporated with a "translational-rotational" dynamic model of compound planetary gear set. Poincare section, the phase trajectory and bifurcation diagram are employed for analysis of periodic and chaotic motion. The results indicate that, tooth wear accumulation result in the reduction in the amplitude of meshing stiffness at the meshing region of double-pair teeth, but makes no difference in meshing stiffness for the meshing region of single-pair teeth. In order to avoid the system being in Chaos motions, under large tooth wear condition, the input speed should be avoided away from 3700 r/min-6725 r/min, so as to keep the system in a stable periodic motion state. [ABSTRACT FROM AUTHOR]

Objective : The function of B7H3, a member of the B7 family of proteins, in neuroblastoma (NB) remains poorly characterized. Here we examine the expression pattern of B7H3 in clinical NB specimens and characterize the phenotype of B7H3 knock-down in NB cell line. Methods : Immunohistochemical (IHC) staining was carried out to assess the expression of B7H3 in clinical NB specimens. Survival association was analyzed using five Gene Expression Omnibus (GEO) datasets (GSE85047, GSE45480, GSE62564, GSE16476, GSE49710). Clonogenic survival and flow cytometry were performed after B7H3 knockdown to assess the cellular proliferation and cell survival in vitro. Impact of B7H3 silencing on NB growth was examined in vivo using the SH-SY5Y xenograft model. Results : On IHC staining, B7H3 was widely expressed in clinical NB specimens. Analysis of the transcriptional profiles of five GEO datasets clinically annotated NB specimens revealed that decreased B7H3 expression was associated with improved overall survival. B7H3 knockdown suppressed the proliferation of the SH-SY5Y NB model in vitro and in vivo. Cell cycle analysis revealed that B7H3 silencing induced G1/S arrest. This arrest was associated with the suppression of E2F1 expression and induction of Rb expression. Conclusion : Our results demonstrate that B7H3 expression correlate with clinical survival in NB patients. Preliminary studies suggest that B7H3 may mediate the G1/S transition. [ABSTRACT FROM AUTHOR]

Pathologic features of Alzheimer's disease (AD) include accumulation of amyloid β (Aβ) and hyperphosphorylated tau protein. We have shown previously that the chemokine-like receptor 1 (CMKLR1) is a functional receptor for β), and CMKLR1 contributes to the uptake of β. However, it is unclear whether CMKLR1 ameliorates or aggravates the process of AD. Here, we show that deletion of the gene coding for CMKLR1 significantly increased β deposits in brains of both male and female amyloid P precursor protein/presenilin-1 mice. However, it markedly decreased the mortality of these mice. Behavioral studies found that CMKLR1 deficiency improved cognitive impairment of male and female amyloid P precursor protein/presenilin-1 mice and intracerebroventricular-streptozotocin injection AD mice. We further explored the effect of CMKLR1 on tau pathology. We found that CMKLR1 deficiency or inhibition attenuated the hyperphosphorylation of tau in brains of AD mice in vivo and in the neuronal cells in vitro. The expression of CMKLR1 on the neurons affected tau phosphorylation by participating in tau seeding. Together, these results uncover a novel mechanism of CMKLR1 in the pathologic process of AD and suggest that inhibiting the promotion effect of CMKLR1 on tau seeding may provide a new strategy for the treatment of AD. [ABSTRACT FROM AUTHOR]

Ferroelectric Bi0.5(Na0.82K0.18)0.5TiO3 (NKBT) thick films have been prepared using screen printing on Pt electroded alumina substrates. The room-temperature dielectric constant of resulting 60 μm thick NKBT film reaches as high as 823 at 1 kHz and the depolarization temperature, Td, locates at 130 °C. The effect of amplitude and frequency of the applied ac field and the aging temperature as well as the Bi excess on the dielectric and piezoelectric aging characteristics are systemically studied. The results show that the dielectric and piezoelectric aging are associated with the reorientation of defect dipoles which stabilized the non-180° domain walls. By this reorientation the domain wall motions are clamped by a time dependent force resulting in the observed decrease in the dielectric and piezoelectric properties during the aging procedural. Moreover, the aging in NKBT thick films exhibits strong frequency dependence, which is caused by that the reorientation and alignment of the defect dipoles with the local polar domains provide a pinning field to the micropolar region, where the regions with larger micropolar volume will experience stronger pinning potential. The NKBT thick films added with 0.5 mol % Bi2O3 exhibit relative lower aging rate of the dielectric constant and piezoelectric coefficient, resulting from the compensation of the Bi3+ vacancies by the addition of small amount of excess Bi2O3. [ABSTRACT FROM AUTHOR]

Background: Juglone is a natural pigment, which has cytotoxic effect against various human tumor cells. However, its cytotoxicity to glioma cells, especially to tumor stem-like cells (TSCs) has not been demonstrated.Methods: TSCs of glioma were enriched from U87 and two primary cells (SHG62, and SHG66) using serum-free medium supplemented with growth factors, including bFGF, EGF and B27. After treatment of juglone with gradient concentrations (0, 10, 20, and 40 μM), the viability and apoptosis of TSCs were evaluated by WST-8 assay and flow cytometry. Reactive oxygen species (ROS) was labeled by the cell-permeable fluorescent probe and detected with flow cytometry. ROS scavenger (NAC) and p38-MAPK inhibitor (SB203580) were applied to resist the cytotoxic effect. Caspase 9 cleavage and p38 phosphorylation (P-p38) were quantified by western blot. Juglone as well as temozolomide (TMZ) were administrated in intracranial xenografts and MR scan was performed every week to evaluate the anti-tumor effect in vivo.Results: Juglone could obviously inhibit the proliferation of TSCs in glioma by decreasing cell viability (P < 0.01) and inducing apoptosis (P < 0.01), which was accompanied by increased caspase 9 cleavage in a dose-dependent manner (P < 0.01). In the meantime, juglone could generate ROS significantly and increase p38 phosphorylation (P < 0.01). In addition, pretreatment with ROS scavenger or p38-MAPK inhibitor could reverse juglone-induced cytotoxicity (P < 0.01). More importantly, juglone could also suppress tumor growth in vivo and improve the survival of U87-bearing mice compared with control (P < 0.05), although TMZ seemed to have better effect.Conclusions: Juglone could inhibit the growth of TSCs in gliomas through the activation of ROS-p38-MAPK pathway in vitro, and the anti-glioma effect was validated in vivo, which offers a potential therapeutic agent to gliomas. [ABSTRACT FROM AUTHOR]

Nine runoff containment basins (RCBs), used directly or indirectly for irrigating plants in ornamental plant nurseries, and one adjacent stream were sampled for water quality between Feb. and July 2013 in Maryland (MD), Mississippi (MS), and Virginia (VA). Triplicate water samples were taken monthly. Analysis was done for 18 water quality variables including nitrate-nitrogen (NO3--N) and ammonium-nitrogen (NH4+-N), orthophosphate-phosphorus (PO4-P) and total-phosphorus (T-P), potassium, calcium, magnesium, sulfur, aluminum, boron (B), copper (Cu), iron (Fe), manganese, zinc (Zn), pH, total alkalinity (T-Alk), electrical conductivity (EC), and sodium. Additionally, 15 RCBs from 10 nurseries in Alabama (AL), Louisiana (LA), and MS were sampled in 2014 and 2016. Most prevalent correlations (P = 0.01) were between macronutrients, EC, B, Fe, and Zn, but none were prevalent across a majority of RCBs. Water quality parameter values were mostly present at low to preferred levels in all 25 waterways. Macronutrient levels were highest for a RCB that receives fertility from fertigation derived runoff. Water pH ranged from acidic to alkaline (>8). Results of this study show water quality in RCBs can be suitable for promoting plant health in ornamental plant nurseries, but also shows levels will vary between individual RCBs, therefore demonstrates need to verify water quality from individual water sources. [ABSTRACT FROM AUTHOR]

Background: The outcomes of atrial fibrillation (AF) between biatrial maze (BAM) and left atrial maze (LAM) are still controversial. The purpose of this study was to compare the clinical and rhythm outcomes between BAM and LAM in patients with AF. Methods: Electronic databases and article references were systematically searched (1990-2014) to access relevant studies. Odds ratio (OR) and weight mean difference (WMD) with 95% confidence interval (CI) were reported. Results: Fourteen studies with 2,075 patients were finally involved in the present metaanalysis. The rate of restored sinus rhythm(SR) was similar in BAM and LAM groups (OR: 1.25, 95% CI: 0.91-1.72, p = 0.163). BAM reduced the prevalence of atrial flutter during follow-up (OR: 0.12, 95% CI: 0.01-0.96, p = 0.046). Compared with BAM, LAM shorten aortic cross-clamping time (WMD = 9.05 minutes, 95% CI: 1.28-16.82, p = 0.023) and cardiopulmonary bypass time (WMD = 20.21 minutes, 95% CI: 7.40-33.03, p = 0.002). No significant difference was found between groups in the risk of death (OR: 1.22, 95% CI: 0.70-2.14, p = 0.233), cerebrovascular events (OR: 1.44, 95% CI: 0.51-4.06, p = 0.493), and reoperation for bleeding (OR: 1.34, 95% CI: 0.70-2.55, p = 0.374). However, the risk for implantation of permanent pacemaker was significantly higher in BAM group (OR: 2.60, 95% CI: 1.09-6.20, p = 0.031). Conclusion: No significant difference was found between BAM and LAM in the rate of restored SR, the risk of death, cerebrovascular events, and reoperation for bleeding. BAM is superior to LAM in reducing the prevalence of atrial flutter during follow-up, but LAM shortens the aortic cross-clamping time and cardiopulmonary bypass time, and decreases the risk of permanent pacemaker implantation. [ABSTRACT FROM AUTHOR]

In order to solve the supersonic inlet control problems during supersonic cruising state, an integrated model and inexact one-dimensional search algorithm are devised to design the inlet control law. An online inlet ramp angle mapping model is also proposed using recursive reduced least squares support vector regression and BP neural network methods. Finally, a proportional and integral (PI) controller is designed to control the inlet ramp. The simulation results indicated that an effective inlet ramp controller would greatly improve the engine installed performance and protect the engine from surge and other dangerous operations. [ABSTRACT FROM AUTHOR]

The intergenic IRES of Cricket Paralysis Virus (CrPV-IRES) forms a tight complex with 80S ribosomes capable of initiating the cell-free synthesis of complete proteins in the absence of initiation factors. Such synthesis raises the question of what effect the necessary IRES dissociation from the tRNA binding sites, and ultimately from all of the ribosome, has on the rates of initial peptide elongation steps as nascent peptide is formed. Here we report the first results measuring rates of reaction for the initial cycles of IRES-dependent elongation. Our results demonstrate that 1) the first two cycles of elongation proceed much more slowly than subsequent cycles, 2) these reduced rates arise from slow pseudo-translocation and translocation steps, and 3) the retarding effect of ribosome-bound IRES on protein synthesis is largely overcome following translocation of tripeptidyl-tRNA. Our results also provide a straightforward approach to detailed mechanistic characterization of many aspects of eukaryotic polypeptide elongation. [ABSTRACT FROM AUTHOR]

OBJECTIVES: Congenital tracheal stenosis (CTS) is variable in patients with tracheal bronchus and congenital heart disease (CHD). Tracheoplasty remains a high-risk surgical treatment. METHODS: From January 2007 to December 2014, 24 CTS patients (10 males and 14 females; age 20.6 ± 13.6 months) with tracheal bronchus and CHD underwent one-stage surgical correction. Clinical features of all patients included dyspnoea, or recurrent pulmonary infections. There was long-segment CTS in 13 cases (54%), and 4 cases were associated with a bridging bronchus. Less than 50% of normal tracheal size was identified in 21 cases. Complete tracheal or bronchial rings were identified in all cases. Operative techniques included: tracheal end-to-end anastomosis in 11 cases and slide tracheoplasty in 13 cases, which included 11 cases of right upper lobe bronchus (RULB) opposite side-slide tracheoplasty. RESULTS: There were 2 operative deaths, due to postoperative tracheomalacia or residual main bronchial stenosis. The duration of postoperative hospital stay was 7-59 days, with an average of 19 days. Follow-up was completed in 19 cases. The follow-up duration was from 1 month to 7 years. Tracheal granulation occurred in 1 case. Clinical symptoms were significantly improved in the remaining patients. CONCLUSIONS: Tracheal bronchi have special anatomical features. The techniques of tracheal end-to-end anastomosis or side-slide tracheoplasty can be used to correct tracheal stenosis with satisfactory outcomes. [ABSTRACT FROM AUTHOR]

The objective of the experiment was to evaluate the effects of dietary carbohydrate composition on rumen fermentation characteristics and microbial populations in vitro. The treatments were organized in three different carbohydrate composition diets: the wheat fibre rich diet (WF) (67.2% wheat bran and 25.7% corn grain in concentration), mixed diet (MD) (45.1% wheat bran and 34.3% corn grain) and corn starch rich diet (CS) (2.1% wheat bran and 63.8% corn grain), respectively (n=6). The results showed that consumption of CS diet led to a decrease in NH3-N (ammonia nitrogen) concentration (P<0.05), and microbial protein concentration were increased (P<0.05). They indicated more efficient ruminal NH3-N utilization and microbial protein (MCP) synthesis with increasing corn starch proportion. Compared with WF diet, concentrations of acetate, propionate and TVFA (total volatile fat acid) were increased in MD and CS diets (P<0.01). The results of Real-time PCR technique indicted that the microbes in rumen were sensitive to dietary carbohydrate composition, and the consumption of CS diets increased Protozoa population, as well as Streptococcus bovis (P<0.05). Butyrivibrio fibrisolvens population of WF and MD (8 h) was higher than that of CS (P<0.01), while Butyrivibrio fibrisolvens population (24 h) got lower within WF treatment (P<0.01). These results indicated that the microbial community structure and improved ruminal fermentation are affected by the composition of dietary carbohydrate. Maximizing nitrogen utilization and MCP synthesis could be obtained when non-structural carbohydrate rich diet (2.1% wheat bran and 63.8% corn grain) was used. [ABSTRACT FROM AUTHOR]

Background 2-phenylethanl (2-PE) and its derivatives are important chemicals, which are widely used in food materials and fine chemical industries and polymers and it's also a potentially valuable alcohol for next-generation biofuel. However, the biosynthesis of 2-PE are mainly biotransformed from phenylalanine, the price of which barred the production. Therefore, it is necessary to seek more sustainable technologies for 2-PE production. Results A new strain which produces 2-PE through the phenylpyruvate pathway was isolated and identified as Enterobacter sp. CGMCC 5087. The strain is able to use renewable monosaccharide as the carbon source and NH4Cl as the nitrogen source to produce 2-PE. Two genes of rate-limiting enzymes, chorismate mutase p-prephenate dehydratase (PheA) and 3-deoxy-d-arabino-heptulosonic acid 7-phosphate synthase (DAHP), were cloned from Escherichia coli and overexpressed in E. sp. CGMCC 5087. The engineered E. sp. CGMCC 5087 produces 334.9 mg L-1 2-PE in 12 h, which is 3.26 times as high as the wild strain. Conclusions The phenylpyruvate pathway and the substrate specificity of 2-keto-acid decarboxylase towards phenylpyruvate were found in E. sp. CGMCC 5087. Combined with the low-cost monosaccharide as the substrate, the finding provides a novel and potential way for 2-PE production. [ABSTRACT FROM AUTHOR]

Background Sabinene, one kind of monoterpene, accumulated limitedly in natural organisms, is being explored as a potential component for the next generation of aircraft fuels. And demand for advanced fuels impels us to develop biosynthetic routes for the production of sabinene from renewable sugar. Results In this study, sabinene was significantly produced by assembling a biosynthetic pathway using the methylerythritol 4-phosphate (MEP) or heterologous mevalonate (MVA) pathway combining the GPP and sabinene synthase genes in an engineered Escherichia coli strain. Subsequently, the culture medium and process conditions were optimized to enhance sabinene production with a maximum titer of 82.18 mg/L. Finally, the fed-batch fermentation of sabinene was evaluated using the optimized culture medium and process conditions, which reached a maximum concentration of 2.65 g/L with an average productivity of 0.018 g h-1 g-1 dry cells, and the conversion efficiency of glycerol to sabinene (gram to gram) reached 3.49%. Conclusions This is the first report of microbial synthesis of sabinene using an engineered E. coli strain with the renewable carbon source as feedstock. Therefore, a green and sustainable production strategy has been established for sabinene. [ABSTRACT FROM AUTHOR]

A two-layer robust control scheme is proposed to get a better response ability for emergency maneuvers of helicopter. Note that the power used in ascending flight is the main coupling between helicopter and its turboshaft engines; therefore vertical flight control is separated from conventional helicopter control loops and combined with fuel flow and turbine bleeding to new control loops denoted as an inner layer, whereas the mission level flight control is as the out layer. A conclusion in global asymptotically tracking for devising this newscheme is firstly derived from a Generalized Gronwall-Bellman approach. Due to this integrated designing, not only is the helicopter better controlled, but also much better power rapid tracking is realized for engines. Simulations are conducted to validate the new scheme in emergent ascending and descending flights, and the results illustrate that the response time of the closed-loop system is dramatically reduced when compared to the traditional one. Moreover, the presented system also has better dynamic performance under inferences. [ABSTRACT FROM AUTHOR]

The antibacterial and antiviral agent amicetin is a disaccharide nucleoside antibiotic featuring a unique α-(1→4)-glycoside bond between amosamine and amicetose, characteristic of a retaining glycosylation. In this study, two key steps for amosamine biosynthesis were investigated: the N- methyltransferase AmiH was demonstrated to be requisite for the dimethylation in amosamine, and the glycosyltransferase AmiG was shown to be necessary for amosaminylation. Biochemical and kinetic characterization of AmiG revealed for the first time the catalytic reversibility of a retaining glycosyltransferase involved in secondary metabolite biosynthesis. AmiG displayed substrate flexibility by utilizing five additional sugar nucleotides as surrogate donors. AmiG was also amenable to sugar and aglycon exchange reactions. This study indicates that AmiG is a potential catalyst for diversifying nucleoside antibiotics and paves the way for mechanistic studies of a natural-product retaining glycosyltransferase. [ABSTRACT FROM AUTHOR]

Methylacetoin (3-hydroxy-3-methylbutan-2-one) and 2-methyl-2,3-butanediol are currently obtained exclusively via chemical synthesis. Here, we report, to the best of our knowledge, the first alternative route, using engineered Escherichia coli. The biological synthesis of methylacetoin was first accomplished by reversing its biodegradation, which involved modifying the enzyme complex involved, switching the reaction substrate, and coupling the process to an exothermic reaction. 2-Methyl-2,3-butanediol was then obtained by reducing methylacetoin by exploiting the substrate promiscuity of acetoin reductase. A complete biosynthetic pathway from renewable glucose and acetone was then established and optimized via in vivo enzyme screening and host metabolic engineering, which led to titers of 3.4 and 3.2 g l-1 for methylacetoin and 2-methyl-2,3-butanediol, respectively. This work presents a biodegradation-inspired approach to creating new biosynthetic pathways for small molecules with no available natural biosynthetic pathway. [ABSTRACT FROM AUTHOR]

A novel scheme of high stability engine control (HISTEC) on the basis of an improved linear quadratic regulator (ILQR), called direct surge margin control, is derived for super-maneuver flights. Direct surgemargin control, which is different fromconventional control scheme, puts surge margin into the engine closed-loop system and takes surge margin as controlled variable directly. In this way, direct surge margin control can exploit potential performance of engine more effectively with a decrease of engine stability margin which usually happened in super-maneuver flights. For conquering the difficulty that aeroengine surge margin is undetectable, an approach based on improved support vector regression (SVR) machine is proposed to construct a surge margin prediction model. The surge margin modeling contains two parts: a baseline model under no inlet distortion states and the calculation for surge margin loss under supermaneuvering flight conditions. The previous one is developed using neural network method, the inputs of which are selected by a weighted feature selection algorithm. Considering the hysteresis between pilot input and angle of attack output, an online scrolling window least square support vector regression (LSSVR)method is employed to firstly estimate inlet distortion index and further compute surge margin loss via some empirical look-up tables. [ABSTRACT FROM AUTHOR]

Amicetin, an antibacterial and antiviral agent, belongs to a group of disaccharide nucleoside antibiotics featuring an α(1→4)glycoside bond in the disaccharide moiety. In this study, the amicetin biosynthesis gene cluster was cloned from Streptomyces vinaceusdrappus NRRL 2363 and localized on a 37-kb contiguous DNA region. Heterologous expression of the amicetin biosynthesis gene cluster in Streptomyces lividans TK64 resulted in the production of amicetin and its analogues, thereby confirming the identity of the ami gene cluster. In silico sequence analysis revealed that 21 genes were putatively involved in amicetin biosynthesis, including 3 for regulation and transportation, 10 for disaccharide biosynthesis, and 8 for the formation of the amicetin skeleton by the linkage of cytosine, p-aminobenzoic acid (PABA), and the terminal (+ )-α-methylserine moieties. The inactivation of the benzoate coenzyme A (benzoate-CoA) ligase gene amiL and the N-acetyltransferase gene amiF led to two mutants that accumulated the same two compounds, cytosamine and 4-acetamido-3-hydroxybenzoic acid. These data indicated that AmiF functioned as an amide synthethase to link cytosine and PABA. The inactivation of amiR, encoding an acyl-CoA-acyl carrier protein transacylase, resulted in the production of plicacetin and norplicacetin, indicating AmiR to be responsible for attachment of the terminal methylserine moiety to form another amide bond. These findings implicated two alternative strategies for amide bond formation in amicetin biosynthesis. [ABSTRACT FROM AUTHOR]

As novel sensors, rotational symmetric triangulation sensors (RSTSs) have broad application potential because of their robustness and accuracy. However, existing RSTSs have the disadvantages of complicated structure and high cost. The current paper presents a novel RSTS based on an object space mirror. The proposed sensor uses a cone mirror and a commercial camera, which significantly simplifies the structure and reduces its cost. Mathematical models are discussed to reveal the measurement range of the sensor and the relation between the displacement of the spot and the radius of the ring in the image. An improved image processing method is also introduced for a more efficient processing. Finally, two experimental systems with mirror angles at π/6 and π/4 are set up. Experimental results showed that the proposed sensor can achieve a comparable accuracy of 1.6 μm compared with that of existing methods, as well as a higher efficiency of image processing, while remaining at a low cost. [ABSTRACT FROM AUTHOR]

Parameter estimation in thermodynamic models has been of great interest in chemical engineering because of its complex nature, including nonlinearity, flat objective function in the neighborhood of the global optimum, badly scaled model, and nondifferential term(s) in the equations. In this article, a stochastic global optimization algorithm called integrated differential evolution (IDE) is introduced to solve the parameter estimation problems for modeling vapor–liquid equilibrium (VLE) data. In IDE, the choice of mutation strategy and associated parameters are adapted according to the learning experience from previous generations. The tabu list used in IDE can avoid revisiting the same area and avoid unnecessary function evaluations. A novel and effective stopping criterion based on the number of rejected points during the generation of a trial vector is tested and compared with other criteria. Furthermore, IDE uses a local optimizer after the global search to find the optimum accurately and efficiently. The performance of IDE for benchmark functions and VLE modeling is compared with that of other stochastic algorithms such as DE, DE with tabu list, particle swarm optimization, simulated annealing, and the deterministic algorithm Branch and Reduce Optimization Navigator (BARON). IDE is shown to be better than or comparable to these algorithms for parameter estimation in modeling VLE data. [ABSTRACT FROM AUTHOR]

Bi0.5(Na0.82K0.18)0.5TiO3(NKBT) lead-free ferroelectric thick films with various porosities have been produced by screen printing. Their microstructures, pyroelectric and piezoelectric properties were investigated with variation of porosity. The results show that the relative dielectric constant of the resulting 90 μm NKBT thick films with 19% and 32% porosity was down to 161 and 56, respectively. The pyroelectric voltage figure of merit ( Fv) and detectivity figure of merit ( FD) of NKBT thick films were increased from 10.2 × 10−13 to 19.7 × 10−13 Cm/J and 1.1 × 10−5 to 3.8 × 10−5 Pa−0.5. Moreover, the hydrostatic voltage constant and hydrostatic figure of merit of the NKBT thick films with 32% porosity reached 81 × 10−3 V/mPa and 8200 × 10−15 Pa−1 respectively. The decreasing of relative dielectric constant, volume specific heat, and piezoelectric coefficient with increasing porosity was responsible for the improved pyroelectric and piezoelectric figures of merit of the NKBT thick films. Furthermore, screen printing with the addition of controlled fraction of organic vehicle in pastes has been proved to be an alternative method for fabrication of porous pyroelectric and piezoelectric thick films. Our work demonstrates that introduction of pores in ferroelectric thick films creates a matrix void composite resulting in high figures of merit for pyroelectric and piezoelectric applications. [ABSTRACT FROM AUTHOR]

La2O3-doped sodium–potassium bismuth titanate (Na0.82K0.18)0.5Bi0.5TiO3 (NKBT) lead-free thick films have been prepared on Pt-electroded alumina substrates using a combination of screen printing and subsequent infiltration of the corresponding composite sol. Their densification, microstructure, dielectric, ferroelectric, pyroelectric, and piezoelectric properties were investigated with variation of the La2O3 content. The resulting 40 μm-thick NKBT films doped with 1.0 mol% La2O3 show minimum leakage current density of 1.56 × 10−9 A/cm2 at an applied field of 100 kV/cm, remanent polarization of 21.6 μC/cm2, and coercive field of 58 kV/cm. The high pyroelectric coefficient of 2.0 × 10−4 C·(m2·°C)−1, the calculated detectivity figure of merit as high as 0.81 × 10−5 Pa−0.5, and the value of remanent d33eff of 108 pm/V at room temperature (20°C) were observed in 1.0 mol% La2O3-doped NKBT thick films, which can be comparable with that of the commonly used lead-based materials. The enhancement of the pyroelectric and piezoelectric performances is attributed to the reduction of lattice tetragonality, uniform microstructure, and improved densification in La-modified NKBT thick films. [ABSTRACT FROM AUTHOR]

Unbalanced energy consumption is an inherent problem in wireless sensor networks characterized by multihop routing and many-to-one traffic pattern, and this uneven energy dissipation can significantly reduce network lifetime. In this paper, we study the problem of maximizing network lifetime through balancing energy consumption for uniformly deployed data-gathering sensor networks. We formulate the energy consumption balancing problem as an optimal transmitting data distribution problem by combining the ideas of corona-based network division and mixed-routing strategy together with data aggregation. We first propose a localized zone-based routing scheme that guarantees balanced energy consumption among nodes within each corona. We then design an offline centralized algorithm with time complexity O(n) (n is the number of coronas) to solve the transmitting data distribution problem aimed at balancing energy consumption among nodes in different coronas. The approach for computing the optimal number of coronas in terms of maximizing network lifetime is also presented. Based on the mathematical model, an energy-balanced data gathering (EBDG) protocol is designed and the solution for extending EBDG to large-scale data-gathering sensor networks is also presented. Simulation results demonstrate that EBDG significantly outperforms conventional multihop transmission schemes, direct transmission schemes, and cluster-head rotation schemes in terms of network lifetime. [ABSTRACT FROM AUTHOR]

MnO-doped 0.82Bi0.5Na0.5TiO3–0.18Bi0.5K0.5TiO3(NBT–KBT) thick films with thickness about 40 μm have been prepared using screen printing on Pt electroded alumina substrates. The strong pyroelectric coefficient of 3.8 × 10−4 C·(m2·°C)–1 was observed in 1.0 mol% MnO-doped-thick films, and the calculated detectivity figure of merit as high as 1.1 × 10−5 Pa−0.5, which can be comparable to that of the commonly used lead based materials. The enhancement of the pyroelectric performances is attributed to the reductions in dielectric constant and loss and the improvements in the pyroelectric coefficient, which can be ascribed to the Mn acts as a hard dopant in the NBT–KBT lattice, creating oxygen vacancies and pinning the residual domains. [ABSTRACT FROM AUTHOR]

Tumours contain immune cells and a network of pro- and anti-inflammatory cytokines, which collaborate in the development and progression of cancer. Cytokine profiles might prove to be prognostic. The systemic effects of pro-inflammatory cytokines are associated with fatigue, depression and cognitive impairment, and can affect quality of life before, during and after treatment. In people with advanced cancer, pro-inflammatory cytokines are additionally associated with anorexia and cachexia, pain, toxicity of treatment and resistance to treatment. However, physical activity might modify cytokine levels and decrease fatigue in patients with cancer, and might also improve their prognosis. [ABSTRACT FROM AUTHOR]

Abstract  The Q cycle mechanism proposed by Peter Mitchell in the 1970’s explicitly considered the modification of ubiquinone two-electron redox properties upon binding to Complex III to match the thermodynamics of the other single-electron redox cofactors in the complex, and guide electron transfer to support the generation of a proton electro-chemical gradient across native membranes. A better understanding of the engineering of Complex III is coming from a now moderately well defined thermodynamic description of the redox components as a function of pH, including the Qi/heme b H cluster. The redox properties of the most obscure component, Qo, is finally beginning to be resolved. [ABSTRACT FROM AUTHOR]

Abstract  Thirty years ago, Peter Mitchell won the Nobel Prize for proposing how electrical and proton gradients across bioenergetic membranes were the energy coupling intermediate between photosynthetic and respiratory electron transfer and cellular activities that include ATP production. A high point of his thinking was the development of the Q-cycle model that advanced our understanding of cytochrome bc 1. While the principle tenets of his Q-cycle still hold true today, Mitchell did not explain the specific mechanism that allows the Qo site to perform this Q-cycle efficiently without undue energy loss. Though much speculation on Qo site mode of molecular action and regulation has been introduced over the 30 years after Mitchell collected his Prize, no single mechanism has been universally accepted. The mystery behind the Qo site mechanism remains unsolved due to elusive kinetic intermediates during Qo site electron transfer that have not been detected spectroscopically. Therefore, to reveal the Qo mechanism, we must look beyond traditional steady-state experimental approaches by changing cytochrome bc 1 thermodynamics and promoting otherwise transient Qo site redox states. [ABSTRACT FROM AUTHOR]

Organochlorine pesticides were used extensively in the Yangtze River Delta, China. However, knowledge about their residual levels and environmental fates in soils of this area is limited. This paper presents the residue isomers and spatial pattern of dichlorodiphenyltrichloroethane (DDT) in soils across 17 main cities in the Yangtze River Delta. Forty-three soil surface (0-15 cm) samples were collected during a field campaign conducted in October 2003 in the Delta. Six DDT isomers (1-[2-chlorophenyl]- 1-[4-chlorophenyl]-2,2-dichloroethane [o,p'-DDD], 1-[2-chlorophenyl]-1-[4-chlorophenyl]-2,2-dichloroethylene [o,p-'DDE], 1,1,1- trichloro-2-[p-chlorophenyl]-2-[o-chlorophenyl]ethane [o,p'-DDT], p,p'-dichlorodiphenyldichloroethane [p,p'-DDD], p,p'-dichlorodiphenyldichloroethylene [p,p'-DDE], p,p'-dichlorodiphenyltrichloroethane [p,p'-DDT]) were detected using gas chromatography. The results show that p,p'-DDE was the dominant isomer in the soil samples. The levels of DDT are generally low in soils of this area and are comparable to DDT levels in other cities in China and in soils from developed countries such as the United States and Germany. The isomer ratios of o,p'-DDT to p,p'-DDT and DDT to (DDD + DDE) were employed to identify the source of DDT. The computed ratios implied that the source of DDT might be related to the application of dicofol, an acaricide manufactured from technical DDTs and mainly used on cotton fields to treat mites. [ABSTRACT FROM AUTHOR]

A series of novel wholly aromatic sulfonated poly(arylene ether) copolymers containing sulfonic acid groups on the pendants SC-SPAE, i.e., side-chain-type sulfonated poly(arylene ether) were prepared by direct copolymerization of sulfonated monomer sodium 4-(4-(2,6-difluorobenzoyl)phenoxy) benzenesufonate (SDFBS), 4,4‘-dichlorodiphenyl sulfone (DCDPS), and 4,4‘-dihydroxyldiphenylether (DHDPE). The sulfonate degree (DS) of the copolymers was readily controlled by adjusting the feed ratio of SDFBS to DCDPS. Structures of the sulfonated copolymers were confirmed by FT-IR and NMR. Tough and flexible films of the wholly aromatic copolymers with good thermal and oxidative stability were obtained by solvent cast process in N,N-dimethylacetamide (DMAc) solution. The films of these side-chain-type copolymers show good dimensional stability, and their water uptake and swelling ratios at high temperature are lower than those of the main-chain-type sulfonated poly(arylene ether) with similar ion exchange capacity (IEC) value. Proton conductivities of the copolymers with high sulfonate degree (DS > 0.7) are higher than 10-2S/cm and increase gradually with increasing temperature. At 100 °C, the conductivities of SC-SPAE90 (DS 0.9, IEC 1.61 mmol g-1) and SC-SPAE100 (DS 1.0, IEC 1.74 mmol g-1) reach 0.12 and 0.14 S/cm, respectively, comparable to that of Nafion117 (0.14 S/cm). [ABSTRACT FROM AUTHOR]

Under mild conditions and without any additional organic solvent, esterification of alcohols by carboxylic acids could be carried out in a halogen-free Brønsted acidic ionic liquid, N-methyl-2-pyrrolidonium methyl sulfonate ([NMP]+CH3SO3−). Good conversion rates and high selectivities were obtained, especially for esterification of ethanol by acetic acid, and the liquid esters formed a separate phase that was decanted. The ionic liquid could be reused after removal of water under vacuum. [ABSTRACT FROM AUTHOR]

Typically, c hemes are bound to the protein through two thioether bonds to cysteines and two axial ligands to the heme iron. In high-potential class I c-type cytochromes, these axial ligands are commonly His-Met. A change in this methionine axial ligand is often correlated with a dramatic drop in the heme redox potential and loss of function. Here we describe a bacterial cytochrome c with an unusual tolerance to the alternations in the heme ligation pattern. Substitution of the heme ligating methionine (M185) in cytochrome c1 of the Rhodobacter sphaeroides cytochrome bc1 complex with Lys and Leu lowers the redox midpoint potential but not enough to prevent physiologically competent electron transfer in these fully functional variants. Only when Met-185 is replaced with His is the drop in the redox potential sufficiently large to cause cytochrome bc1 electron transfer chain failure. Functional mutants preserve the structural integrity of the heme crevice: only the nonfunctional His variant allows carbon monoxide to bind to reduced heme, indicating a significant opening of the heme environment. This range of cytochrome c1 ligand mutants exposes both the relative resilience to sixth axial ligand change and the ultimate thermodynamic limits of operation of the cofactor chains in cytochrome bc1. [ABSTRACT FROM AUTHOR]

The glutamic acid residue of the conserved PEWY motif of the Qo site of cytochrome bC1 is widely discussed as central to reversible Qo site catalysis of two-electron, two-proton hydroquinone-quinone oxidation-reduction. Extensive mutation of this glutamate (E295) to A, V, F, H, K, and Q in purple photosynthetic Rhodobacter capsulatus results in hydroquinone oxidation rates that are between 5 and 50-fold slower than that in the wild type. However, the mutants show little or no detectable effects on hydroquinone or quinone exchange and binding at the Qo site nor on subsequent Qo site-mediated redox equilibria in the c-chain and b-chain from pH 5–10. Lack of effects of mutations on the Em/pH plots rules out involvement of E295 in the strong electron-proton coupling evident in either the FeS center or heme bL. These detailed equilibrium and kinetic analyses demonstrate that E295 is not irreplaceable in the Qo site catalytic mechanism. Rather, E295 and several other Qo site residues that can also be widely varied and still support hydroquinone oxidation illustrate the considerable resilience of Qo site activity to mutational change in Qo site environs. Residues and water molecules appear to cooperate in providing a physical and chemical environment supporting hydroquinone oxidation rates comparable to those seen in nonprotein aqueous environments at electrodes. We suggest that residues at the Qo site (and, possibly, other respiratory and photosynthetic quinone and oxygen binding sites) are a product of natural selection primarily acting not to lower catalytic barriers according to the traditional view of enzymatic catalysis but rather to develop specificity by raising barriers in defense of semiquinone loss or energy wasting short-circuit reactions. [ABSTRACT FROM AUTHOR]

(Ba 1-x Sr x )TiO 3 (BST) ferroelectric thin films with Pb doped from 1 to 10 mol % were fabricated on Pt/Ti/SiO 2 /Si substrates by sol-gel technique in order to improve the crystallographic properties and decrease the ferroelectric relaxation and the diffuse phase transition. The microstructures, surface morphology, dielectric properties, and ferroelectric properties of BST thin films were studied. The Pb doping increased the BST grain size, lowered the diffusion phase transition, and narrowed the diffuse phase region of BST thin films. We found that 5 mol% Pb doped (Ba 0.8 Sr 0.2 )TiO 3 thin films show a strong preferential orientation of crystallites in (110), excellent ferroelectric properties, the better crystallographic properties, and low loss tangent, which is basically suitable for the detecting materials of uncooled infrared focal plane arrays (UFPAs). The 5 mol% Pb doped BST thin films with dielectric constant of 402, loss tangent of 0.011, remanent polarization of 3.8 μCcm -2 , a coercive field of 45 kVcm -1 have been fabricated by using sol-gel process. [ABSTRACT FROM AUTHOR]

A modified Sol-Gel process was used to get the higher-performance BST thin films. The BST thin films possessed different composites and structures in the substrate of Pt/Ti/SiO2/Si. The microstructure, morphology and the electrical properties of the prepared BST thin films were investigated via X-ray diffractometry, scanning electron microscopy techniques and measurement techniques. The results show that the optimum processing for BST films is RTA750°C × 20 min and with sandwich structure seed layers. BST20 film with good resistivity, comparatively dielectric and ferroelectric properties is practical for the detecting materials of UFPA. The system with dielectric constant of 405, loss tangent of 0.011, remanent polarization of 2.3 μC cm-2, a coercive field of 45 kV cm-1 can be obtained by the modified Sol-Gel processing. [ABSTRACT FROM AUTHOR]

RATIONALE AND HYPOTHESISAcute lung injury is a frequent complication of severe sepsis or blood loss and is often associated with an excessive inflammatory response requiring mechanical ventilation. We tested the hypothesis that the types of fluids used during early resuscitation have an important effect on the evolution of lung injury.METHODSRats were subjected to either hemorrhage or endotoxemia for 1 hr, followed by resuscitation to a controlled mean blood pressure with Ringer''s lactate, 5% albumin, or 25% albumin for 1 hr. After resuscitation, blood cytokine levels were measured. The lung was then excised and ventilated with a tidal volume of 30 mL/kg for 2 hrs.RESULTSThe volume of fluids required was significantly smaller in the albumin-treated groups than in the Ringer''s lactate groups. In the hemorrhagic shock model, plasma concentrations of tumor necrosis factor-α, interleukin-6, and macrophage inflammatory protein-2 were significantly lower and interleukin-10 was significantly higher in the albumin-treated groups compared with the Ringer''s lactate-treated group. The levels of tumor necrosis factor-α and macrophage inflammatory protein-2 in bronchoalveolar lavage fluid were lower and interleukin-10 was higher in the albumin-treated groups than in the Ringer''s lactate group. The decreased cytokine production was associated with a reduction of hydrogen peroxide formation with albumin resuscitation. The lung wet/dry ratio was lower in the 5% albumin (0.54 ± 0.01) and 25% albumin (0.55 ± 0.02) groups than in the Ringer''s lactate group (0.62 ± 0.02; both p < .05). These effects of albumin seen in the hemorrhagic shock model were not observed in the endotoxic shock model.CONCLUSIONSWe conclude that resuscitation with albumin may have utility in reducing ventilator-induced lung injury after hemorrhagic shock, but not after endotoxic shock. These findings suggest that the mechanisms leading to ventilator-induced lung injury after hemorrhage differ from those after endotoxemia. [ABSTRACT FROM AUTHOR]

OBJECTIVEWe examined the hypothesis that mechanical ventilation with a potentially injurious strategy would predispose animals to the detrimental effects of subsequent instillation of bacteria.DESIGNInterventional animal study.SETTINGA university hospital research laboratory.SUBJECTSFifty Sprague-Dawley male rats.INTERVENTIONSRats were anesthetized and randomized to receive a protective (tidal volume 7 mL/kg, positive end-expiratory pressure 5 cm H2O, n = 25) or an injurious ventilatory strategy (tidal volume 21 mL/kg, zero positive end-expiratory pressure, n = 25). Hemodynamics were similar during the 1-hr ventilation period in the two groups. Animals were then disconnected from the ventilator and Pseudomonas aeruginosa was instilled intratracheally before extubation. Thereafter, animals breathed spontaneously; mortality rate was assessed up to 48 hrs, at which time the animals were killed.MEASUREMENTS AND MAIN RESULTSThe 48-hr mortality rate was 28% in the protective group and 40% in the injurious group (p = not significant). A positive bacterial culture from the lung was obtained in 56% of the surviving rats in the low tidal volume group and 67% in the high tidal volume group (p = .059). A positive blood bacterial culture was found in 11% of the low tidal volume group and 33% in the high tidal volume group (p < .05). The absolute bacterial count in the blood was lower in the low tidal volume group compared with the high tidal volume group (p < .05). Concentrations of blood tumor necrosis factor-α and macrophage inflammatory protein-2, and lung macrophage inflammatory protein-2 at 48 hrs were significantly higher in the low tidal volume group than in the high tidal volume group.CONCLUSIONSAn injurious ventilatory strategy predisposes animals to subsequent bacteremia associated with an impaired host defense reflected by cytokine response. [ABSTRACT FROM AUTHOR]

OBJECTIVEThis study was designed to compare the effects of continuous venovenous hemofiltration (CVVH) with two different membranes, polysulphone and polyacrylonitrile (AN69), on global and regional hemodynamics, plasma lactate, tumor necrosis factor-α levels, and plasma nitrite/nitrate during endotoxic shock in dogs.METHODSFifteen pentobarbital anesthetized and mechanically ventilated dogs were randomized into three groups of five dogs each. One group served as an endotoxin alone, time matching group and, 1 hr after endotoxin administration, the two other groups received CVVH at 3 L/hr for 270 mins, with either a polysulphone membrane or an polyacrylonitrile membrane.RESULTSAt 90 mins after endotoxin administration, dogs receiving CVVH with polyacrylonitrile membranes had a higher cardiac output, stroke volume, and left-ventricular stroke work index than the endotoxin alone and the polysulphone groups. CVVH with either polyacrylonitrile or polysulphone membranes prevented the rise in pulmonary artery pressure and pulmonary vascular resistance compared with the endotoxin alone group. Plasma lactate levels were not significantly altered, but the fall in bicarbonate seen in the endotoxin alone group did not occur in the two CVVH groups. Tumor necrosis factor levels in the plasma were not significantly altered by CVVH and remained very low (<50 pg/mL) in the ultrafiltrate fluid.CONCLUSIONIn this acute endotoxic shock model, CVVH with the polyacrylonitrile membrane improved cardiac performance when compared with the polysulphone membrane. These effects could be caused by a more effective adsorption of inflammatory mediators other than tumor necrosis factor. Whether the polyacrylonitrile membrane should be preferred over the polysulphone membrane for CVVH in severe sepsis warrants further experimental and clinical study. [ABSTRACT FROM AUTHOR]

Investigates the role of neutrophil defensins in mediating acute inflammatory response and lung dysfunction in dose-related fashion. Significance of intratracheal instillation of purified defensins; Association between lung dysfunction and neutrophil influx.

Tests the hypothesis that neutrophil defensins mediate acute inflammatory response and lung dysfunction in a dose-related fashion. Measurement of elastinolytic activity; Peripheral arterial oxygen saturation; Influence of intratracheal instillation of defensins on lung mitochondrial cytochrome c concentrations.

Presents information on a study which investigated the role of human neutrophil peptides or defensins on acute lung dysfunction of mice. Effects of defensins on neutrophil migration and activation; Regulatory effects of defensins on the production of pulmonary and systemic cytokines; Materials and methods used; Clinical relevance of the doses of defensins used.

The fundamental principle of the transient state control method for turbofan engines, which is based on the acceleration ratio of high-pressure rotational speed (N-dot), involves sacrificing a portion of the safety margin to obtain satisfactory acceleration performance. However, it could induce surge in the engine's compressor. To prevent the destructive damage caused by surge to both the engine and its components, a surge-elimination control strategy for the engine based on an N-dot controller is proposed. First, the engine mathematical model, which incorporates the effects of engine volumetric dynamics, stall zone characteristics, and combustion chamber flameout characteristics, is established to simulate surge mechanism. Subsequently, the acceleration schedule of the N-dot is calculated by employing sequential quadratic programming (SQP) algorithm to solve the multiconstraint optimization problem, while designing the transition state controller of N-dot based on a high-order filter. Finally, the surge detection logic and surge-elimination strategy based on the µ-correction method are proposed and designed to realize active control of surge elimination. The simulation results demonstrate that the N-dot control method offers significant advantages in mitigating the steady-state errors resulting from inevitable engine degradations. The surge state is effectively suppressed by the proposed surge-elimination control method, and the surge duration is significantly shorten during the acceleration phases. Furthermore, compared to the one without any surge-elimination control, the proposed method decreases the acceleration time by 5.53%. [ABSTRACT FROM AUTHOR]

It is unclear what effect biological sex has on outcomes of acute lung injury (ALI). Clinical studies are confounded by their observational design. We addressed this knowledge gap with a preclinical systematic review of ALI animal studies. We searched MEDLINE and Embase for studies of intratracheal/intranasal/aerosolized lipopolysaccharide administration (the most common ALI model) that reported sex-stratified data. Screening and data extraction were conducted in duplicate. Our primary outcome was histological tissue injury and secondary outcomes included alveolar-capillary barrier alterations and inflammatory markers. We used a random-effects inverse variance meta-analysis, expressing data as standardized mean difference (SMD) with 95% confidence intervals (CIs). Risk of bias was assessed using the Systematic Review Centre for Laboratory Animal Experimentation (SYRCLE) tool. We identified six studies involving 132 animals across 11 independent experiments. A total of 41 outcomes were extracted, with the direction of effect suggesting greater severity in males than females in 26/41 outcomes (63%). One study reported on lung histology and found that male mice exhibited greater injury than females (SMD: 1.61, 95% CI: 0.53–2.69). Meta-analysis demonstrated significantly elevated albumin levels (SMD: 2.17, 95% CI: 0.63–3.70) and total cell counts (SMD: 0.80, 95% CI: 0.27–1.33) in bronchoalveolar lavage fluid from male mice compared with female mice. Most studies had an “unclear risk of bias.” Our findings suggest sex-related differences in ALI severity. However, these conclusions are drawn from a small number of animals and studies. Further research is required to address the fundamental issue of biological sex differences in LPS-induced ALI. [ABSTRACT FROM AUTHOR]

Similarity of nitroimidazole and nitrofuran antibiotics in molecular structure and photophysical properties makes them difficult to distinguish via luminescence sensing technology. Herein, this is solved by a dye-encapsulated lanthanide metal--organic framework luminescent sensor. [ABSTRACT FROM AUTHOR]

Derives analytical solutions of the transients in the main and branch discharging routes in a Cockcroft-Walton cascade rectifier circuit. Response to a load short-circuit discharge; Investigation of transient currents, energy dissipation in the circuit elements and the effects of circuit parameters.

Focuses on the negative resistance characteristics of Zener diode at onset of avalanche breakdown. Observation of the negative resistance effect in a low current region within a narrow voltage near the onset of primary breakdown; Current voltage and oscillation characteristics of high- and low-voltage Zener diodes in low current region.

The polarization-field hysteresis (P-E) loops of Pb(Mn1/3Nb1/3Sb1/3)x(Zr0.825Ti0.175)1–xO3(PMnNSZT) ferroelectric ceramics show pinched shapes instead of the normal squarelike P-E loops in the range of 0.02≤x≤0.1. The pinched loops are assumed to be the result of the pinning effect of the defect dipoles. The absence of the pinched shape P-E loops can be attributed to the depinning resulting from strong p-type conductivity in PMnNSZT ceramics with high doping concentration of x>0.1. The x-ray photoelectron spectrum and x-ray diffraction investigations indicate that the p-type conductivity of the grain boundaries results from the aggregation of excessive B-site doping. [ABSTRACT FROM AUTHOR]

Piezoelectric Bi0.5(Na0.82K0.18)0.5TiO3 thick films were screen printed on Pt electroded alumina substrates. The resulting 38 μm thick films sintered at 1100 °C for 0.5 h have maximum relative permittivity of 810, dielectric loss of 2.0% (at 10 kHz), remanent polarization of 28.3 μC/cm2, coercive field of 62 kV/cm, and longitudinal effective piezoelectric coefficient d33eff of 109 pm/V. The temperature dependence of the dielectric constant shows two clear peaks that were associated with phase transitions. The performance of this lead free piezoelectric thick film could be comparable to the corresponding bulk ceramics. [ABSTRACT FROM AUTHOR]