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A field campaign (29 May to 14 June 2018) was conducted at a mountain site in central China. The chemical composition of non‐refractory submicron particulate matter (NR‐PM1) and the particle number size distribution (PNSD) were measured, respectively. The mean NR‐PM1 mass concentration was 20.94 ± 10.14 μg m−3, among which organics (47%) was the most abundant component, followed by sulfate (37%), ammonium (11%), nitrate (4%), and chloride (1%). Notably, sulfate accounted for more than 70% of the secondary inorganic aerosols. Positive matrix factorization (PMF) analysis of the composition data resulted in three organic aerosol (OA) factors: hydrocarbon‐like OA (HOA), oxygenated OA I (OOA‐I), and oxygenated OA II (OOA‐II). The secondary organic aerosol (SOA) composed of the latter two factors (SOA: OOA‐I + OOA‐II) was dominant in OA (80.7%). The PMF analysis of the PNSD data yielded three factors: new particle formation related mode, growth mode, and accumulation mode, among which the last factor dominated both number and volume ratios. The sulfate formation was characterized by the sulfur oxidation ratio (SOR), heterogeneous sulfate production rate (Phet), and gaseous sulfuric acid concentration, representing secondary sulfate transformation, heterogeneous reactions, and gas phase reactions, respectively. The results showed that Phet was well correlated with both sulfate concentrations and SOR, especially during the polluted periods. Our study demonstrates that photochemically‐driven heterogeneous reactions contribute dominantly to the sulfate formation and SOA is formed predominantly by photochemical oxidation of volatile organic compounds under high temperatures and ultraviolet (UV) intensities, and NOX concentrations on Mt. Wudang during the campaign period. Plain Language Summary: In this study, the chemical composition and size distribution of submicron aerosols were measured at a mountain site in central China (Mt. Wudang), and the sources as well as controlling factors were further investigated. Our results reveal that photochemical reactions play an important role in both sulfate and secondary organic aerosol formation. For sulfate, heterogeneous reactions were dominant during the polluted periods, whereas gas‐phase reactions are more pronounced during the clean periods. Key Points: Organics and sulfate account for more than 80% mass concentration of submicron aerosols on Mt. WudangHeterogenous reactions lead to sulfate formation on Mt. Wudang during the polluted periodsSecondary organic aerosol was mainly formed by photochemical reactions on Mt. Wudang [ABSTRACT FROM AUTHOR]

Examines the microanalysis on the diffraction intensity to determine the aluminum concentration for aluminum compound multiple quantum-well structures. Development of technique for monitoring of surface conditions during the growth of aluminum compound semiconductor layers; Details on the simulation; Discussion on the results of the study.

For the past 2 years, interest in manufacturing technologies based on micro-fluidic systems has been continuously increasing. Today, micro-fluidic systems are used in numerous biomedical and pharmaceutical applications. Micro-fluidics cannot be thought about separately without advances in micro- and nano-fabrication. Investigations based on experiments, finite element modelling and simulations of powder hot embossing process (PHE) were performed to optimise the sintering step and processing parameters of micro-fluidic components. The model pertaining to thermo-elasto-viscoplastic behaviour was identified for 316L stainless steel powders. In this regard, different material properties such as sintering stress, bulk, and shearing viscosities were identified by inverse analysis from present dilatometer measurements using beam-bending and free sintering tests. The identification of materials was performed for various powder volume loadings and kinetic rates for different 316L elaborated feedstock, and the parameters were obtained as functions of relative density. The initial inhomogeneity due to the PHE process has been taken into account in the sintering simulation, as it affects the final shrinkage of the sintered components. The solid-state sintering simulations were investigated for various final sintering temperatures and kinetic rates to obtain high and homogeneous relative density distributions, achieve isotropic shrinkage and optimise the sintering process parameters. The numerical simulations were realised based on the identified parameters on a 3D micro-structured specimen with an associated rectangular plate support elaborated by PHE; this allowed a comparison between the numerical predictions and the experimental results for the sintering stage. The finite element simulation results of the sintering stage with a micro-fluidic structured component at a high final temperature (1360 °C) are in excellent agreement with the results of the experiments. The comparison of the simulation and experimental results validated the identified and implemented physical model and proposed methodologies. [ABSTRACT FROM AUTHOR]

Liquid silicone rubber (LSR) is a family of high-technology elastomer materials. The member of this family has been identified as being very promising for development in the coming decades due to their unique properties and ease of generation in large series by the injection moulding process. In particular, the over-moulding of LSR on other materials, such as thermoplastic polymers, metals and ceramics, is possible today, which leads to the possibility of obtaining multi-material, functional multi-colour and newly featured components. The work presented in this paper focuses on the transformation of liquid silicone rubber to better understand the phenomena involved to improve production processes and to optimize the processing conditions for bi-material components in well-defined geometry and functional properties. The rheological, rheo-kinetic and thermal behaviours of silicone elastomers were investigated and characterized under real conditions of manufacture with different combined methods. A thermo-rheo-kinetic model was then developed and implemented using the moulding simulation software Cadmould 3D to simulate two-component injection moulding of silicone rubber into a thermoplastic polymer. For the validation of the models chosen and the parameters identified, bi-material injection moulding tests of a two-component standard peel test specimen (polyamide thermoplastic polymer/liquid silicone rubber) were performed and compared to numerical results. [ABSTRACT FROM AUTHOR]

Elastomer injection moulding is a process whereby an elastomer mix is injected into a closed mould where the material is shaped to the desired geometry. Once completely filled, the silicone elastomer mix is vulcanised. Vulcanisation is the process whereby a viscous flow of silicone is converted into an elastic material through the incorporation of chemical cross-links between the material chains. To correctly use simulation tools to predict the filling of die mould cavities, it is necessary to characterise the material in terms of their rheological properties and kinetic behaviour during curing. The aim of this study was to develop mathematical models for the thermo-kinetic parameters of elastomers that can properly predict the filling of the die mould cavity. In this work, a rotational rheometer was used to determine changing viscosity and vulcanisation characteristics of a silicone compound. The rheokinetic properties of different silicone fluid samples were measured over a broad temperature range from 25 to 100 °C and are reported in this paper. Good agreement was obtained between the experimental results and the model predictions. The methods proposed could well represent the overall experimental data for different silicone elastomers; thus, it could be readily employed for simulation of the elastomer injection moulding process. [ABSTRACT FROM AUTHOR]

In this work, a variant of the incremental sheet forming (ISF) process, namely the incremental sheet forming by using water jet (ISF-WJ), was studied. In the investigation, an ISF-WJ prototype machine was designed and developed. Different design concepts of the water jet nozzle were proposed and evaluated to achieve the maximum forming pressure by performing computational fluid dynamic (CFD) simulations. Based on the forming pressure distribution modeled by CFD simulations, finite element (FE) models were developed to study the sheet deformation behavior under the ISF-WJ process condition. Based on the understanding gained from the numerical study, experiments were conducted to validate the ISF-WJ process and the developed prototype machine. The results suggest that ISF-WJ is a feasible process to achieve improved surface finish of thin sheet parts. In addition, this study has found that water jet pressure plays an important role in preventing sheet wrinkling and obtaining an accurate geometry of formed parts. [ABSTRACT FROM AUTHOR]

Presents a study which developed a surface potential model for the subband structures in the inversion layer of narrow-gap semiconductor heterostructures. Review of related literature; Computational approach; Results.

Presents a study which focused on an experimental model for evaluating the hole subband structures in the p-type channel of semiconductor heterostructures. Measurement of the hole subband structure; Relevant parameters obtained for the hole subband; Conclusion.

Preform design plays a significant role in forging design especially for parts with complex shapes. Conventional preform design approaches include trial-and-error approach, electric field method, and shape optimization-based approaches. In this paper, by introducing the structural design optimization concept, a 3D topological preform design optimization method has been developed. In this method, a new criterion for element elimination and addition is proposed and employed for plastic deformation problems in blade forging. Based on the finite element (FE) simulation combined with optimization, the optimized preforms with and without equal cross-section constraint can be obtained. Using the optimized preform, physical experiment on forging of a blade has been implemented to validate the optimization result. Other preform-related issues, such as the feasible approaches for preparation of optimized preforms, are also discussed in detail. The result suggested that the optimized preforms could improve the deformation uniformity during forging processes with better die-filling rate and reduced waste of raw materials. [ABSTRACT FROM AUTHOR]

In this paper, we report recent work in cranial plate manufacturing using incremental sheet forming (ISF) process. With a typical cranial shape, the ISF process was used to manufacture the titanium cranial shape by using different ISF tooling solutions with and without backing plates. Detailed evaluation of the ISF process including material deformation and thinning, geometric accuracy and surface finish was conducted by using a combination of experimental testing and Finite Element (FE) simulation. The results show that satisfactory cranial shape can be achieved with sufficient accuracy and surface finish by using a feature based tool path generation method and new ISF tooling design. The results also demonstrate that the ISF based cranial reconstruction has the potential to achieve considerable lead time reduction as compared to conventional methods for cranial plate manufacturing. This outcome indicates that there is a potential for the ISF process to achieve technological advances and economic benefits as well as improvement to quality of life. [ABSTRACT FROM AUTHOR]

To assess the quality of volcanic rock used as pozzolan in cement-based materials, two methods are introduced to estimate the pozzolanic activity component of volcanic rock based on X-ray diffraction data and chemical composition. Pozzolanic activity component is calculated by rock method as the product of rock composition (SiO2 + Al2O3) content and rock amorphous phase content determined by X-ray diffraction over the entire range. In the mineral method, pozzolanic activity component is calculated as the sum of the active component SiO2 content and the active component Al2O3 content, which are calculated by the chemical composition and amorphous phase proportion determined from X-ray diffraction data of quartz and feldspar, respectively. An excellent positive correlation was observed between the two pozzolanic activity component types. Both calculated pozzolanic activity components had separately positive correlations with the pozzolanic activity index measured as the ratio of mortar strengths. The results could be applied to judge the potential of volcanic rock for use as pozzolan. [ABSTRACT FROM AUTHOR]

IC lead frame scraps with about 18.01% tin, 34.33% nickel, and 47.66% iron in composition are industrial wastes of IC lead frame production. The amount of thousand tons of frame scraps in Taiwan each year is treated as scrap irons. Ni-Zn ferrites used in high frequent inductors and filters are produced from Ni-Zn ferrite powders by pressing and sintering. The amount of several ten thousand tons of ferrites of Ni1-XZnXFe2O4 in compositions is consumed annually in the whole world. Therefore, these IC lead frame scraps will be used in this research as raw materials to fabricate magnetic ferrite powders and combined subsequently with titanium sulfate and urea to produce magnetic photocatalysts by coprecipitation for effective waste utilization. The prepared Ni-Zn ferrite powder and magnetic photocatalyst (Ni-Zn ferrite/TiO2) were characterized by ICP, XRF, XRD, EDX, SEM, SQUID, and BET. The photocatalytic activity of synthesized magnetic photocatalysts was tested by FBL dye wastewater degradation. TOC and ADMI measurement for degradation studies were carried out, respectively. Langmuir-Hinshelwood kinetic model of the prepared magnetic TiO2 proved available for the treatments. Wastes are transformed to valuable magnetic photocatalysts in this research to solve the separation problem of wastewater and TiO2 photocatalysts by magnetic field. [ABSTRACT FROM AUTHOR]

Interleukin-5 (IL-5) increases the secretion of natural T15/EO6 IgM antibodies that inhibit the uptake of oxidized low-density lipoprotein (LDL) by macrophages. This study aimed to determine whether macrophage-specific expression of IL-5 in LDL receptor-deficient mice (Ldlr−/−) could improve cholesterol metabolism and reduce atherosclerosis. To induce macrophage-specific IL-5 expression, the pLVCD68-IL5 lentivirus was delivered into Ldlr−/− mice via bone marrow transplantation. The recipient mice were fed a Western-type diet for 12 weeks to induce lesion formation. We found that IL-5 was efficiently and specifically overexpressed in macrophages in recipients of pLVCD68-IL5-transduced bone marrow cells (BMC). Plasma titers of T15/EO6 IgM antibodies were significantly elevated by 58% compared with control mice transplanted with pLVCD68 lacking the IL-5 coding sequence. Plaque areas of aortas in IL-5-overexpressing mice were reduced by 43% and associated with a 2.4-fold decrease in lesion size at the aortic roots when compared with mice receiving pLVCD68-transduced BMCs. The study showed that macrophage-specific overexpression of IL-5 inhibited the progression of atherosclerotic lesions. These findings suggest that modulation of IL-5 cytokine expression represents a potential strategy for intervention of familial hypercholesterolemia and other cardiovascular diseases. [ABSTRACT FROM AUTHOR]

The relentless increase in network capacity is making it important to reduce power consumption. In optical access network systems, the buffer size in layer-2 switches, which aggregate multiple passive optical network systems, is expanding as the network speed increases, and the buffer is now significant in terms of power consumption. An effective way to reduce the buffer size is to adopt dynamic bandwidth allocation for a layer-2 switch; however, this leads to low bandwidth efficiency. In this paper, we propose a dynamic bandwidth allocation framework that is suitable for application to a layer-2 switch. The performance of the proposed scheme is evaluated by both computer simulations and experiments, and it is shown that the proposed scheme provides better performance than the conventional scheme with regard to buffer size with high bandwidth efficiency. [ABSTRACT FROM PUBLISHER]

Incremental sheet forming (ISF) is a highly versatile and flexible process for producing low batches of sheet metal parts. Although finite element (FE) method is a key approach in the study of material deformation in metal forming processes, the application of FE in ISF process is still limited. This is due to the enormous simulation time required for ISF processes. Focusing on this problem, this paper presents a new selective element fission (SEF) approach for simulation of ISF process based on LS-DYNA. In the approach, the computational efficiency is improved by reducing the unnecessary calculations of elements outside the localized deformation zone in the ISF process. The introduction of a background mesh for simulation data storage and a separate simulation mesh with varied mesh density for simulation ensures both the efficiency of computation and accuracy of results. To verify the proposed SEF method, two ISF case problems including a hyperbolic cone part and a pyramid part are studied by comparing to the conventional FE approach and the H-adaptive approach in terms of the CPU time, the forming load, the final part profile, and thickness distribution. The influence of two key factors: element size ratio and toolpath segment length is also studied. The results suggested that the developed SEF approach can save the CPU time by up to 74 % with satisfactory accuracy as compared to conventional FE method, which demonstrates both the effectiveness and robustness of the developed SEF approach. [ABSTRACT FROM AUTHOR]

This paper presented a recent work on preform design optimization in bulk metal forming process based on a topological approach. In the paper, to obtain a forging preform shape with reduced material consumption but enhanced uniform material deformation, a new element removal and addition criterion has been established with consideration of hydrostatic stress and strain components. In order to overcome the problem that the size of FE mesh for forging simulation cannot be directly used for topology optimization, background mesh was employed for optimization evolution while coarser but smoother FE mesh was employed for FE simulation. The other key techniques developed include an interpolation method and surface smoothing treatment for jagged surface after element addition and elimination. A C# program for optimization system integrated with DEFORM-3D finite element (FE) software package is developed and an industrial case problem: forging of a 3D aeroengine blade is investigated. Considering the feasibility of producing a preform, different constraints are applied in the optimization process to affect the preform shape. The optimization results are presented and discussed, which suggest that the developed topology optimization method is an efficient approach for 3D preform design and optimization. [ABSTRACT FROM AUTHOR]

Conventional spinning is a widely used metal forming process to manufacture rotationally axis-symmetric and asymmetric products. Considerable efforts have been made to investigate the forming quality of spun parts using the process in recent years. However, inherent uncertainty properties involved in the spinning process are rarely considered in previous studies. In this paper, an uncertainty analysis and process optimisation procedure have been developed and implemented on conventional spinning with 3D Finite Element Method (FEM). Three process variables are randomized by Gaussian distribution to study the probabilistic characteristics of two process responses. Linear and quadratic approximate representations are constructed by Monte Carlo based Response Surface Method (RSM) with Latin Hypercube Sampling (LHS). The Most Probable Point (MPP) method, which has been widely used to estimate the failure probability in other applications, is further developed in this paper to obtain the probability distribution of the system responses. Following an evaluation of the system responses conducted by the MPP method, a control variable method is used to reduce the variance of spun part wall thickness and total roller force to satisfy the 3 σ quality requirement. This uncertainty analysis and process optimisation procedure can be easily implemented in other metal spinning processes. [ABSTRACT FROM AUTHOR]

The paper presents a direct shape optimization approach that minimizes both boundary stress concentration and peak contact pressure of multi-body contact systems. This approach is centered on the direct shape modification of boundary regions of stress concentration measured by von Mises stresses and contact surfaces measured by contact pressure. Without requiring sensitivity data for shape modification, shape optimization is made directly on nodal positions through an iterative computational scheme. Therefore, this approach is simple to implement using either commercial finite element software or in-house programs. An adjustable weighting factor is used to ensure stable and accelerated convergence in shape optimization. To evaluate the proposed approach, three case problems are presented, and the results show that this direct shape optimization approach can be especially applicable to the design and analysis of multi-body systems where boundary stress concentration and contact pressure distribution are an important consideration. [ABSTRACT FROM AUTHOR]

Wind power has had a striking development in recent years. However, advanced materials and technology for manufacturing wind turbines are necessary but usually unavailable in a developing country like Taiwan. In such a case, the consumption of transportation energy, especially an international one, cannot be ignored while the energy efficiency of wind power systems is surveyed. Based on our analysis, three demonstration wind systems in Taiwan, Mailiao, Jhongtun, and Chunfong, were analyzed to examine how the consumption of transportation energy affects the energy return on investment (EROI) and CO2emission for wind energy. We have found the EROI loss increases while the transportation energy consumption is considered. Notably, the transportation of mega wind turbines leads to more CO2emission. Moreover, wind turbines in small load capacities have less transportation energy ratio, while mega turbines consume disproportionately more transportation energy. [ABSTRACT FROM AUTHOR]

Reasons for performing the study: In contrast with reports in man and small animals, a systematic classification of seizures in horses is lacking. Objectives: The purpose of this study was to classify seizures based on their aetiology and to characterise epilepsy in 104 horses presented for seizures at the Ohio State University Veterinary Medical Center between 1988 and 2009. Methods: In a retrospective observational study, seizures were classified by aetiology based on history, clinical observations, diagnostic investigations (e.g. electroencephalograms, cerebrospinal fluid and computed tomography imaging of the head) and post mortem examinations, when available. Univariate and multivariate logistic regression analyses were performed. Results: Epilepsy (i.e. 2 or more recurrent seizures) was identified in 70% of cases, and further classified as symptomatic (i.e. structural brain pathology, 35.6% of cases), cryptogenic (i.e. unknown, 54.8% of cases) and idiopathic (i.e. suspected genetic predisposition, 2.7% of cases). Normal neurological examination on admission, the presence of seizures unprovoked by any identified factors and paroxysmal epileptiform activity on electroencephalogram recordings were all strongly (P<0.05) correlated with epilepsy on univariate analysis. For a horse with generalised seizures, the odds of having epilepsy was 7 times lower compared with a similar horse with partial seizures (P<0.05) in multivariate modelling. Conclusions: Seizure aetiology was symptomatic or cryptogenic in most horses, whereas reactive seizures and idiopathic epilepsy were less common. Potential relevance: This study is the first attempt to classify seizures and to characterise epilepsy in a referral-based equine population. Predictive factors of epilepsy in horses were similar to those reported in other species and may assist the clinician with the early diagnosis of epilepsy. [ABSTRACT FROM AUTHOR]

This paper presents an improved approach to characterize press elastic behaviour and to quantify the effect of press elasticity in the forging of three-dimensional (3D) complex shapes. Using a stiffness matrix formulation, the overall press elasticity is characterized by press elastic deformation and initial clearances of the press guideway. The effect of press elasticity in forging is evaluated by implementing the press stiffness matrix formulation into the 3D forging simulation using a user subroutine. An industrial-based 3D blade forging case study was carried out to assess the robustness and efficiency of this approach in the forging of 3D complex shapes. Compared with cases without press elasticity, the results show that the press elasticity has less effect on forging force requirements, material deformation, and stress and strain distributions. However, the effect of press elasticity is more apparent on the dimensional and shape accuracy of the forged blade with the initial guideway clearance as a major source for dimensional errors compared with the press elastic deformation. The case study also shows that this approach can be easily implemented for evaluating press tool-related effects in forging simulation and design. [ABSTRACT FROM PUBLISHER]

The stochastic nature of the forging process is a key influencing factor for achievable dimensional and shape accuracy of forged aerofoil blades for aero-engine applications. In this article, a finite-element-based stochastic modelling and optimization method is presented for net-shape forging of three-dimensional (3D) aerofoil blades. A combined Monte Carlo simulation and response surface method as well as the first-order second-moment reliability method are developed to quantify the stochastic characteristics of forging errors due to uncertainties of process parameters and forging conditions. A two-step optimization approach is presented to minimize systematic errors using a direct compensation method and to reduce random variations through a variance control procedure. A 3D blade forging case study is presented to evaluate the stochastic characteristics of the dimensional errors of forged aerofoil blades in comparison with measurement data and to demonstrate much improved forging accuracy using the proposed stochastic optimization method. The results from the case study also suggest that the stochastic-based optimization method may be easily applied to other metal-forming processes. [ABSTRACT FROM AUTHOR]

Retinol binding protein 4 (RBP4) is an adipokine secreted by adipose tissue and liver and contributes to insulin resistance (IR) in animals. Although several human studies indicated that RBP4 is positively correlated with blood pressure and is elevated in untreated hypertensive subjects, the role of RBP4 in IR of hypertensive animals still remains obscure. In this study, spontaneously hypertensive rats (SHR) were used to investigate the relationship between RBP4 levels and IR. We found that at 7 weeks old, SHR had significantly increased plasma RBP4 levels and RBP4 expression in liver and epididymal adipose tissue accompanied by worsening of IR as compared with Wistar-Kyoto (WKY) control rats. Administration of fenretinide in SHR to increase urinary RBP4 excretion significantly decreased plasma RBP4 levels and improved IR. Moreover, treatment with valsartan markedly reduced blood pressure, circulating RBP4 and adiponectin levels, and IR in SHR. Valsartan also reversed the increase of hepatic gluconeogenic enzyme phosphoenolpyruvate carboxykinase (PEPCK) and the decrease of type 4 glucose transporter (GLUT4) in adipose tissue. In conclusion, these results suggest that RBP4 contributes, at least partly, to the pathogenesis of IR in SHR. Furthermore, the decrease of blood pressure caused by valsartan not only decreased RBP4 levels, but also improved IR in SHR. [ABSTRACT FROM AUTHOR]

CdS/Titanate nanotubes (TNTs) were successfully synthesised by a simple, rapid, and reliable microwave hydrothermal method. The CdS nanoparticles synthesised using a 140-W microwave irradiation power at 423 K photodegraded 26% ammonia in water, while the photocatalytic efficiency increased to 52.3% using the synthesised CdS/TNTs composites. The results indicated that the CdS/TNTs photocatalysts possess improved photocatalytic activity than that of CdS or TNTs materials alone. [ABSTRACT FROM AUTHOR]

This study evaluated the proliferative effects of chishao on RSC96, Schwann cells. A dose-dependent proliferative effect of chishao was obtained by methylthiazol tetrazolium (MTT), proliferating cell nuclear antigen (PCNA) Western blotting, and wound healing assays in Schwann cells administered with chishao (0-500 mg/ml), except at 500 mg/ml concentration. The chishao-treated cells also showed a dose-dependent activated fibroblast growth factor-2 (FGF-2) signaling with increased urokinase plasminogen activator (uPA) and decreased plasminogen activator inhibitor-1 (PAI-1), enhanced proliferative proteins, extracellular signal regulated kinase (ERK) and c-Jun N-terminal kinase (JNK)-signaling. Using mitogen-actvated protein kinase (MAPK)-signaling chemical inhibitors, U0126, SB203580, and SP600125, the proliferative effects of chishao on RSC cells were identified to be ERK- and JNK- signaling dependent. Based on the results, applying appropriate doses of chishao to Schwann cells would be a potential approach for enhancing neuron regeneration. [ABSTRACT FROM AUTHOR]

p73 and p63, the two ancestral members of the p53 family, are involved in neurogenesis, epithelial stem cell maintenance and quality control of female germ cells. The highly conserved oligomerization domain (OD) of tumor suppressor p53 is essential for its biological functions, and its structure was believed to be the prototype for all three proteins. However, we report that the ODs of p73 and p63 differ from the OD of p53 by containing an additional α-helix that is not present in the structure of the p53 OD. Deletion of this helix causes a dissociation of the OD into dimers; it also causes conformational instability and reduces the transcriptional activity of p73. Moreover, we show that ODs of p73 and p63 strongly interact and that a large number of different heterotetramers are supported by the additional helix. Detailed analysis shows that the heterotetramer consisting of two homodimers is thermodynamically more stable than the two homotetramers. No heterooligomerization between p53 and the p73/p63 subfamily was observed, supporting the notion of functional orthogonality within the p53 family. [ABSTRACT FROM AUTHOR]

Germanium (Ge) nanocrystals embedded in silica matrix is an interesting material for new optoelectronic devices. In this paper, standard silica-on-silicon waveguides with a core doped by Ge nanocrystals were fabricated using plasma enhanced chemical vapour deposition and reactive ion etching. The cross-sectional waveguide structures were investigated by scanning electron microscopy. Transmission of the waveguide was measured using a broadband light source covering the wavelength range from 500 nm to 1700 nm, and the results were compared against transmission through a standard waveguide. Strong absorption peaks at 1056.8 nm, 1263.2 nm and 1406 nm were observed. These are assigned to the quantum confinement effect in Ge nanocrystals in the core. Putting Ge nanocrystals in a waveguide enables easy material characterisation and potential application in an integrated lightwave circuit device. [ABSTRACT FROM AUTHOR]

: Objectives The aim of the study was to determine whether ATPase genes of genetically diverse Acinetobacter baumannii isolates are disrupted by potential genomic islands. : Methods Random amplified polymorphic DNA (RAPD)-PCR, sequence grouping and PFGE were used to investigate the genetic diversity of 50 A. baumannii isolated from various clinical specimens. PCR analysis was then used to identify isolates with a potentially disrupted ATPase gene. Representative genetically distinct isolates were further characterized by PCR mapping and chromosome walking to analyse the flanking regions of the disrupted ATPase genes. : Results Forty-one of the 50 isolates tested appeared to contain a disrupted ATPase gene. Sequence group and PFGE data for 10 ATPase PCR-negative representative isolates confirmed substantial genetic diversity. Seven isolates contained elements with ends showing high levels of sequence similarity to one or both extremities of AbaR1, the first resistance island described in A. baumannii. A further isolate, A25, possessed a highly conserved AbaR1-like 3′-end, but a divergent, though related, 5′-terminus that exhibited near identity with a distinct locus in A. baumannii ATCC 17978. A ninth isolate (A92) possessed a completely novel sequence abutting on its 5′-ATPase remnant. Three isolates appeared to lack 3′-ATPase gene segments, as was the case with the recently sequenced strain ACICU. Thus, 8 of the 10 ATPase-negative isolates investigated in detail had ATPase genes disrupted with AbaR1-like flanking regions. : Conclusions ATPase genes of diverse A. baumannii isolates are frequently disrupted by insertions matching AbaR1-related flanking sequences. However, the ATPase gene of isolate A92 was disrupted by a DNA sequence distinct from those found in AbaR1. [ABSTRACT FROM AUTHOR]

This paper reports the formation of Ge nanoclusters in a multi-layer structure consisting of alternating thin films of Ge-doped silica glass and SiGe, deposited by plasma-enhanced chemical vapor deposition (PECVD) and post annealed at 1100 °C in N2 atmosphere. We studied the annealed samples by transmission electron microscopy (TEM) and Raman spectroscopy. As-deposited and annealed samples were analyzed by secondary ion mass spectroscopy (SIMS). TEM investigation shows that Ge nanoclusters were formed in the as-deposited SiGe layer and the SiGe layer was transformed into a silicon dioxide layer embedded with Ge nanoclusters after annealing. These nanoclusters are crystalline and varied in size. There were no clusters in the Ge-doped glass layer. Raman spectra verified the existence of crystalline Ge clusters. The positional shift of the Ge vibrational peak with the change of the focus depth indicates that the distribution of the stress applied to the Ge clusters varies with depth. SIMS measurements show clearly the dramatic O increase in the as-deposited SiGe layer after annealing. The creation of Ge nanoclusters by the combination of PECVD and annealing makes possible the application in complicated waveguide components. [ABSTRACT FROM AUTHOR]

This paper presents research for developing a virtual inspection system that evaluates the dimensional tolerance of forged aerofoil blades formed using the finite element (FE) method. Conventional algorithms adopted by modern coordinate measurement processes have been incorporated with the latest free-form surface evaluation techniques to provide a robust framework for the dimensional inspection of FE aerofoil models. The accuracy of the approach had been verified with a strong correlation obtained between the virtual inspection data and coordinate measurement data from corresponding aerofoil components. [ABSTRACT FROM AUTHOR]

This paper reports the formation of Ge nanoclusters in silica glass thin films deposited by plasma-enhanced chemical vapor deposition (PECVD). We studied the samples by transmission electron microscopy (TEM) and Raman spectroscopy after annealing. TEM investigation shows that the Ge nanoclusters at two areas were formed by different mechanisms. The Ge nanoclusters formed in a single row along the interface of a silicon substrate and the silica glass film by annealing during high-temperature heat treatment. Ge nanoclusters did not initially form in the bulk of the film but could be subsequently formed by the electron-beam irradiation. The interface between the silicon substrate and the silica glass film was investigated by Raman spectroscopy. The shift of the Raman peaks around 286.8 cm-1 and 495 cm-1 suggests that the interface is a Si1-xGex alloy film and that the composition x varies along the film growth direction. [ABSTRACT FROM AUTHOR]

This paper presents an approach to predict dimensional errors in 3D complex shapes due to press geometry errors and elasticity. Using a press stiffness matrix formulation for the press deflections in forging operation, a quantitative relationship between forging die deviations and the press geometry errors and elastic deflections is developed, which is a function of the forging force, press stiffness and the spatial relationship between the forging dies and the press table. The stiffness matrix of a screw press is obtained using finite element analysis. To evaluate the effect of the press elasticity on dimensional errors of 3D components, a case study of forging for aerofoil shapes is carried out based on the results from physical modelling experiments. With the representative information of the tool shape and forging force data, numerical results of the forging die deviations as a source of dimensional errors for the aerofoil shape are obtained and evaluated. It is demonstrated that this approach is applicable to forging and other metal forming processes for complex shapes. [ABSTRACT FROM AUTHOR]

Aim : To evaluate the effectiveness of a computerized, errorless learning-based memory rehabilitation program for Chinese patients with traumatic brain injury (TBI). Methods : This study adopted a pre- and post-test quasi-experimental design. A total of 37 patients with TBI were randomly assigned to a Computer-Assisted Memory Training Group (CAMG), a Therapist-administered Memory Training Group (TAMG) and a Control Group (CG). Except for the CG, the patients in both the CAMG and TAMG groups received, respectively, 1-month memory training programmes that were similar in content but differed in delivery mode. All patients were followed up 1 month after treatment. The outcome measures that were taken were the Neurobehavioural Cognitive Status Examination (NCSE or Cognistat), the Rivermead Behavioural Memory Test (RBMT) and The Hong Kong List Learning Test (HKLLT). Repeated measure analyses were performed to investigate differences among the three groups. Results : The patients in the Computer-assisted Memory Rehabilitation (CAMG) and Therapist-administered Memory Rehabilitation group (TAMG) were found to perform better than the CG in the NCSE and RBMT, but no significant differences were found between the CAMG and TAMG. The CAMG showed significant improvement in their HKLLT assessment as compared with the TAMG and CG. No statistically significant differences were found between the CAMG and TAMG when comparing the post-training outcome measures with the follow-up results. Conclusion : There is no difference between CAMG and TAMG, but the efficacy has been demonstrated when comparing with CG. It is suggested that the combined use of an errorless learning and a computerized approach may be an effective way of enhancing the memories of patients with TBI. This new method may smooth the progress of the whole human memory process and produce a better carryover treatment effect. [ABSTRACT FROM AUTHOR]