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The aim of this study was to compare the mechanical properties of three-dimensionally (3D)-printed and conventional surgical plates used for the repair of maxillary or mandibular defects under the same experimental conditions, and to provide experimental evidence for the future application and clinical trial of 3D-printed individualized surgical plates. For the experimental group, two groups of surgical plates with thicknesses of 2.0 mm and 2.5 mm were designed and 3D-printed by electron beam melting, using Ti–6Al–4V as raw material. Conventional commercially available surgical plates with the same thickness were adopted as the control group. A Vickers hardness tester and universal testing machine were used to measure the mechanical properties of the plates (hardness, bending strength, tensile strength, and yield strength). The mechanical properties of 3D-printed surgical plates were significantly better than those of conventional surgical plates of the same thickness (P < 0.001). Comparing the surgical plates of different thickness, the 2.5 mm-thick plates had the highest bending strength in the experimental group (P < 0.001) and the best hardness (P < 0.001), bending strength (P = 0.001), tensile strength (P = 0.001), and yield strength (P = 0.001) in the control group. No statistical difference was found between the two kinds of plates in the experimental group in terms of hardness (P = 0.060), tensile strength (P = 0.096), and yield strength (P = 0.496). The 3D-printed surgical plates have better mechanical properties than the conventional ones. [ABSTRACT FROM AUTHOR]

Foot pad dermatitis (FPD) is a serious problem of the modern poultry industry, negatively affecting birds' welfare and health status, walking and feeding activity, growth performance, carcass quality, and economic performance of meat production. The gut microbiome in poultry with FPD has not been previously investigated. Therefore, we compared the cecal microbiomes of 8 breeding ducks with FPD to 8 control ducks (breeders with apparently healthy feet) by pyrosequencing the bacterial 16S ribosomal RNA gene. The results showed a significant β-diversity (P < 0.05) of cecal microbiota presented between healthy and FPD-affected breeder ducks. The plasma endotoxins, interleukin 1β (IL-1β), IL-17, IL-6, IL-10, and tumor necrosis factor-α concentration, and the abundance of class Clostridia in FPD-affected ducks was markedly higher (P < 0.05), however, the abundance of genus Prevotella, Lactobacillus, Lachnospiraceae UCG-008, and the Firmicutes to Bacteroidetes ratio in FPD-affected ducks was significantly lower (P < 0.05) when compared to healthy ducks. These findings suggest when duck breeders are affected with FPD, ducks show an increased inflammatory response and a difference of structure and composition of the cecal microbiome. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate the effect of dietary energy concentration on growth performance, serum biochemical indices, and the mRNA expression of inflammatory cytokines in the liver of meat ducks challenged with lipopolysaccharide (LPS). A total of 600 1-d-old Cherry Valley meat ducks were randomly assigned to 10 treatments with six replicate cages of 10 birds/pen. A 5 × 2 factorial arrangement in a complete randomized design experiment was used to study the effect of five concentrations of dietary metabolizable energy (ME, 2,800, 2,900, 3,000, 3,100, and 3,200 kcal/kg) with or without a challenge with LPS in meat ducks. All experimental ducks were intraperitoneally injected with either 0.5 mg/kg body weight (BW) LPS or an equivalent amount of sterile saline at 15, 17, and 19 d of age. The results showed that LPS challenge significantly decreased (P < 0.05) BW (d 21), body weight gain (d 15–21) and average daily feed intake (ADFI; d 15–21), and markedly increased (P < 0.05) relative spleen weight, serum total protein concentration, and the mRNA expression of interleukin 6 (IL-6), interleukin 10, transforming growth factor β (TGF-β), and Avian Beta Defensin 10 (AVBD-10) in the liver of meat ducks. Ducks fed 3,200 kcal/kg ME diet had the lowest (P < 0.05) ADFI than those fed with the other diets. Additionally, there were significantly LPS by diet interactions on IL-6, interferon-γ, TGF-β, AVBD-10, and inducible nitric oxide synthase mRNA expression (P < 0.05), wherein a more pronounced liver inflammatory response was observed in birds fed high-energy diets (3,100 and 3,200 kcal/kg ME) than birds fed low-energy diet (2,800 and 2,900 kcal/kg ME). The results indicated that 3,100 and 3,200 kcal/kg ME of diets increased hepatic inflammatory markers induced by LPS challenge in ducks but did not influence performance responsiveness during this challenge. [ABSTRACT FROM AUTHOR]

This paper presents a numerical study of the gap resonance between two side-by-side barges by using a multiphase Navier-Stokes equations model. In order to verify the multiphase flow model, it is firstly applied to simulate a two-dimensional gap resonance problem for two fixed boxes under various wave conditions. A comparison of the free surface elevations obtained on successively refined grids confirms the mesh convergence of numerical solutions. The calculated wave elevation response amplitude operators (RAOs) in the gap compare well with the experimental measurements. The multiphase flow model is further extended to calculate a three-dimensional gap resonance problem for two adjacent rectangular barges. The computed free surface RAOs in the gap also agree well with the experimental results. A close examination of the flow velocity and vorticity in the gap region at the piston resonant mode reveals that large amount of vortices are generated by the sharp corners of the two barges and shed downwards, which provide an effective mechanism to dissipate the flow kinematic energy and to reduce the wave elevation in the gap. On the contrary, rounded corners are not able to induce the same level amount of vortices to dampen the gap resonance. The effects of incident wave steepness on the viscous damping associated with the twin-barge system are highlighted. [ABSTRACT FROM AUTHOR]

The nonlinear dynamic responses of a fully submerged payload hanging from a fixed crane vessel are investigated numerically. A three dimensional fully nonlinear time domain model based on the boundary element method is implemented to perform the analysis. Both the payload and fixed crane vessel are considered to be periodically excited by regular waves inside the numerical tank. The motion of the payload is found to exhibit various nonlinear phenomena (for example, sub-harmonic motion, period doubling behavior) due to the presence of fixed crane vessel. Analysis tools such as the phase trajectory, bifurcation diagram and Poincaré map are used to investigate the motion characteristics of this submerged payload which is undergoing constrained pendulum motions in various scenarios. Parametric studies are also performed by varying several design parameters in order to evaluate the sensitivity of the nonlinear phenomena. Different orientations of the crane vessel and submerged payload are also considered and the results obtained reveal several important conclusions concerning the dynamic behavior of the submerged payload of offshore crane vessel during operations. It is found that change of wave motion frequency coupled with various orientations of the floating barge and submerged payload significantly alters the payload motion behavior and introduces various nonlinear phenomena. The present study can be further extended to identify the limits of the operating conditions of floating cranes and to devise techniques to control or damp the unexpected motions of the submerged payload. [ABSTRACT FROM AUTHOR]

The room-temperature solvent vapor annealing of polystyrene- b -polydimethylsiloxane (PS- b -PDMS) block copolymer films was studied in situ by grazing incidence small-angle X-ray scattering. Films of cylinder-forming PS- b -PDMS with molecular weight 16 kg/mol and 12.2 kg/mol, annealed under vapors of toluene:heptane with varying composition, exhibited swelling-ratio-dependent evolution of microdomain spacing and orientation. In a vapor made from a toluene:heptane 5:1 volumetric ratio liquid mixture, or from pure toluene, cylindrical microdomains reoriented from majority out-of-plane to in-plane during annealing, while drying led to shrinkage along the film normal and a large distortion of the hexagonal lattice of in-plane cylinders. Annealing under vapor from a toluene:heptane 1:5 volumetric ratio liquid produced a non-bulk lamellar structure in the 16 kg/mol PS- b -PDMS. [ABSTRACT FROM AUTHOR]

The aim of this paper is to critically assess the methods used for the evaluation of wave-induced loads on ships examining analytical, numerical and experimental approaches. The paper focuses on conventional ocean going vessels and loads originating from steady state and transient excitations, namely slamming, sloshing and green water, for the latter, and including extreme or rogue waves, as well as the more occasional loads following damage. The advantages and disadvantages of the relatively simpler potential flow approaches against the more time consuming CFD methods are discussed with reference to accuracy, modeling nonlinear effects, ease of modeling and of coupling with structural assessment procedures, suitability for long term response prediction and suitability for integration within design and operational decision making. The paper also assesses the uncertainties involved in predicting wave-induced loads and the probabilistic approaches used for the evaluation of long term response and fatigue analysis. The current design practice is reviewed and the role of numerical prediction methods within the classification framework and goal based design approach discussed. Finally the suitability of current developments in prediction methods to meet the needs of the industry and future challenges is assessed. [ABSTRACT FROM AUTHOR]

Square and circular cylinders in three-dimensional turbulent flows are studied numerically using the LES and DES turbulence models. One aim of the present study is to implement the LES and DES turbulence models in a cell-centered finite volume method (FVM) developed for solving the Navier–Stokes equations on Cartesian cut cells. The Cartesian cut cell approach is known to be robust for problems in geometrically complex domains with fixed or moving boundaries. For the purpose of validating the present numerical model, the current flow past fixed square and circular cylinders at moderate Reynolds numbers is tested first. Comparison of the computed results with experimental data reveals that the DES models are superior to the conventional LES and RANS models. The second aim of the present study is to assess the performance of different RANS based DES turbulence models. By means of the comparison of results obtained with the 0-equation mixing-length, 1-equation S–A and 2-equation k – ω based DES models for the flow over the same circular cylinder, some recommendations are proposed. According to the present study, in terms of accuracy the 1-equation S–A based DES model is very promising. Beside this, if the computational cost is the main concern, the 0-equation mixing-length based DES model might be an ideal option, achieving a good balance between accuracy and efficiency. [ABSTRACT FROM AUTHOR]

The wave interaction with a submerged cylindrical payload subjected to constrained motions in presence of a nearby floating crane barge is investigated in the three-dimensional numerical wave tank using a fully nonlinear potential flow model in the time domain. Numerical simulations are carried out to investigate the hydrodynamic features of this submerged payload under pendulum motion in water waves as well as while it moves towards the sea bed at a constant vertical velocity. It is known that the presence of multiple side by side floating bodies in waves can create significant drift motion. In the present study the similar drift motion is observed for the side by side floating barge and submerged payload and it appears that the submerged payload under constrained motions may face a very large mean drift motion of nearly seven times that of the incident wave amplitude in the beam sea upstream condition. Emphasis is also given towards investigating and understanding the influences of natural frequency of the payload and shielding effect due to the presence of the floating barge. It is found that natural frequency coupled with shielding effect generates remarkable low frequency components in payload responses both in the head sea and the beam sea situations. The effect of different cable lengths, wave maker frequencies and downward moving velocities on payload responses under several geometric setups are studied and compared, and interesting features such as increased low frequency movement of the payload near the natural frequency region and existence of considerable low frequency motions even at a greater depth (while the payload is quite below the free surface) are observed. [ABSTRACT FROM AUTHOR]

In this paper, a numerical model is developed to investigate the liquid sloshing in a real sized rectangular LNG tank when the LNG carrier is travelling in sea conditions. The numerical model solves the Navier–Stokes equations and continuity equation by using a finite difference approximation in an arbitrary moving coordinate system to represent the two-dimensional tank under three-degree-of-freedom excitations. To track the violent movement of the free surface, the level set method is applied to simulate the liquid and gas phases simultaneously. The numerical model is validated by simulating four sloshing cases under various excitations and comparing the present results with the published experimental data and numerical solutions. The emphasis of this study is put on the numerical simulation of sloshing waves in the real sized LNG tank excited by the ship motions. To achieve this, the realistic motion RAOs of the ship in seas are applied directly as the external excitation to generate the sloshing waves. A parametric study regarding filling level, excitation frequency and wave amplitude is finally performed and discussed. [ABSTRACT FROM AUTHOR]

The traditional potential flow theory to describe fully nonlinear waves is reformulated by separating the contributions from incident and scattered waves, in order to improve the computational efficiency. The nonlinear incoming wave is specified explicitly and the modified nonlinear free surface boundary conditions for the scattered wave are expressed in the full Lagrangian description. At each time step only the scattered wave is solved using a mixed Eulerian–Lagrangian scheme by a higher-order boundary element method. The accuracy of the newly developed model is illustrated by comparisons with existing experimental and numerical data in the case of wave diffraction around an array of circular cylinders. Wave resonances in the gap between two side-by-side barges in beam seas, as in Molin et al. [1] , are simulated with the barges subjected to regular waves. To clearly understand the gap resonant responses, long time simulations are performed to achieve final steady states, and the resonant mode shapes of the gap surface are presented. The gap free surface RAOs (Response Amplitude Operators) in the case of mild waves are found to agree well with linear calculations. The nonlinear effects on the resonant response due to the free surface conditions are then investigated. The first resonant frequency is found to shift but the peak value is not changed much with increasing incoming wave steepness, which is known as stiff/soft spring behavior of a nonlinear system. Through the investigation of barges with different drafts, the stiff and soft spring behaviors are identified. [ABSTRACT FROM AUTHOR]

Abstract: In this work we present a numerical model to predict the bubble size distribution in turbulent bubbly flows. The continuous phase is described by the volume-averaged Navier–Stokes equations, which are solved on an Eulerian grid, whereas the dispersed or bubble phase is treated in a Lagrangian manner, where each individual bubble is tracked throughout the computational domain. Collisions between bubbles are described by means of a hard-sphere model. Coalescence of bubbles is modeled via a stochastic inter-particle encounter model. A break-up model is implemented with a break-up constraint on the basis of a critical Weber value augmented with a model for the daughter size distribution. A numerical parameter study is performed of the bubble break-up model implemented in the deterministic Euler–Lagrange framework and its effect on the bubble size distribution (BSD) is reported. A square bubble column operated at a superficial gas velocity of 2cm/s is chosen as a simulation base case to evaluate the parameters. The parameters that are varied are the values of the critical Weber number ( ), the daughter size distribution (β) and the superficial gas velocity ( ). Changes in the values of and have a significant impact on the overall BSD, while a different shaped β did not show a significant difference. [Copyright &y& Elsevier]

Abstract: The evaluation of structural responses is key element in the design of ships and offshore structures. Fundamental to this is the determination of the design loads to support the Rule requirements and for application in direct calculations. To date, the current design philosophy for the prediction of motions and wave-induced loads has been driven by empirical or first-principles calculation procedures based on well-proven applications such as ship motion prediction programs. In recent years, the software, engineering and computer technology available to predict the design loads imposed on ships and offshore structures has improved dramatically. Notwithstanding, with the stepwise increase in the size and structural complexity of ships and floating offshore installations and the advances in the framework of Rules and Standards it has become necessary to utilise the latest technologies to assess the design loads on new designs. Along the lines of the recommendations from the International Ship and Offshore Structures Committee (ISSC) I.2 on Loads this paper reviews some of the recent advances in the assessment of loads for ships and offshore structures with the aim to draw the overall technological landscape available for further understanding, validation and implementation by the academic and industrial communities. Particular emphasis is attributed on methodologies applicable for the prediction of environmental and operational loads from waves, wind, current, ice, slamming, sloshing and operational factors. Consideration is also given to deterministic and statistical load predictions based on model experiments, full-scale measurements and theoretical methods. [Copyright &y& Elsevier]

Abstract: The wave diffraction around an array of fixed vertical circular cylinders is simulated in a numerical wave tank by using a fully nonlinear model in the time domain. The emphasis of the paper lies in the insightful investigation of the nonlinear properties of the near-trapping phenomenon associated with the multiple cylinders. The numerical model is validated by analytical solutions as well as experimental data for waves propagating past two and four vertical cylinders in certain arrangements. An array of four identical circular cylinders at the corners of a square with an incident wave along the diagonal of the square is the main focus here for investigating the near-trapping phenomenon. When near-trapping occurs, the present study shows that an extremely high wave elevation near the cylinders can be observed. At the same time, the hydrodynamic forces on different cylinders are found to be either in phase or out of phase, leading to some characteristic force patterns acting on the whole structure. Due to the nature of the numerical model adopted, nonlinearity at different orders can be captured using a harmonic analysis. In addition to first- and second-order near-trapping, the third-order (triple-frequency) nonlinear component is presented for the first time. For the configuration selected, it is found that at one specific incident wave frequency and direction one trapped mode is excited by second-order effects, while a different trapped mode (having similar symmetries) is excited by the third harmonic of the incident wave frequency. [Copyright &y& Elsevier]

Background: For late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) assessment of atrial scar to guide management and targeting of ablation in atrial fibrillation (AF), an objective, reproducible method of identifying atrial scar is required. Objective: To describe an automated method for operator-independent quantification of LGE that correlates with colocated endocardial voltage and clinical outcomes. Methods: LGE CMR imaging was performed at 2 centers, before and 3 months after pulmonary vein isolation for paroxysmal AF (n = 50). A left atrial (LA) surface scar map was constructed by using automated software, expressing intensity as multiples of standard deviation (SD) above blood pool mean. Twenty-one patients underwent endocardial voltage mapping at the time of pulmonary vein isolation (11 were redo procedures). Scar maps and voltage maps were spatially registered to the same magnetic resonance angiography (MRA) segmentation. Results: The LGE levels of 3, 4, and 5SDs above blood pool mean were associated with progressively lower bipolar voltages compared to the preceding enhancement level (0.85 ± 0.33, 0.50 ± 0.22, and 0.38 ± 0.28 mV; P = .002, P < .001, and P = .048, respectively). The proportion of atrial surface area classified as scar (ie, >3 SD above blood pool mean) on preablation scans was greater in patients with postablation AF recurrence than those without recurrence (6.6% ± 6.7% vs 3.5% ± 3.0%, P = .032). The LA volume >102 mL was associated with a significantly greater proportion of LA scar (6.4% ± 5.9% vs 3.4% ± 2.2%; P = .007). Conclusions: LA scar quantified automatically by a simple objective method correlates with colocated endocardial voltage. Greater preablation scar is associated with LA dilatation and AF recurrence. [Copyright &y& Elsevier]

MicroRNA are approximately 18- to 22-nucleotide nonprotein coding molecules that play important roles in the regulation of gene expression at the posttranscriptional level. In the present study, we assessed the suitability of 8 noncoding small RNA as normalizers for microRNA (miR) quantitative analysis in milk somatic cells of lactating yaks, including 3 small nuclear RNA (snRNA; RNU1A, RNU5A, and RNU6B), 3 small nucleolar RNA (snoRNA; SNORA73A, Z30, and SNORA74A), 1 rRNA (5S), and 1 transfer RNA (Met-tRNA). The snRNA RNU1A, RNU5A, and SNORA73A were identified as the most stable references in milk somatic cells of lactating yaks. Also, a minimum of 3 reference RNA (RNU1A, RNU5A, and SNORA73A) were required for the normalization of microRNA expression data in milk somatic cells of the lactating yak. We further evaluated the suitability of the combination of RNU1A, RNU5A, and SNORA73A as reference RNA in milk somatic cells of lactating yaks via detecting the relative expression of miR 16b, miR 21-5p, miR 145, and miR 155 as microRNA of putative interest. In comparison to the colostrum period, on the whole, the expressions of the 4 microRNA were found to be upregulated at an early period and, thereafter, a declining pattern was exhibited from early to final periods in all microRNA investigated. Based on the results from this study, we recommend that the combination of RNU1A, RNU5A, and SNORA73A can be used as normalizers for microRNA quantitative analysis in future longitudinal studies on milk somatic cells of lactating yaks in relation to lactation. [ABSTRACT FROM AUTHOR]

Abstract: Five-layered Aurivillius Bi6Ti3Fe2O18 (BTF2) polycrystalline thin films were prepared by a chemical solution deposition route. The crystalline structures and microstructures were characterized by X-ray diffractometer, micro-Raman spectrometer and atomic force microscopy. Its electrical and magnetic properties were investigated, and especially optical properties were addressed in detail. Coexistence of the ferroelectric and weak ferromagnetic properties indicated the multiferroic behavior of the BTF2 films. The optical dielectric functions in the photon energy range of 1.13–4.13eV have been extracted by fitting the experimental data in the light of the Tauc–Lorentz dispersion model. A direct interband transition with bandgap energy ~3.72eV was determined for the BTF2 films. The weak absorption below band-gap edge was explained by the Urbach band tail rule. Finally, the optical dispersion behaviors of the BTF2 films in the transparent oscillating region were described using a single oscillator model. [Copyright &y& Elsevier]

Abstract: Hemodynamic changes during pregnancy can result in cardiovascular decompensation in women with pre-existing cardiac diseases. Despite optimized medical treatment, some patients with severe structural cardiac abnormalities may need surgical intervention during pregnancy. We describe a woman who presented at 20 weeks of gestation with acute heart failure due to cor triatriatum, a rare form of congenital heart disease. This condition is characterized by a perforated fibromuscular membrane dividing the left atrium into two chambers. The clinical presentation varies from asymptomatic to acute heart failure depending on the size of the fenestrations in the membrane and the presence of associated cardiac malformations. In our patient, two severely restrictive orifices in a membrane within the left atrium, moderate to severe pulmonary hypertension and good biventricular function were demonstrated by transthoracic echocardiography. Without surgical resection, the increased blood volume and cardiac output associated with pregnancy could have resulted in cardiovascular decompensation. She underwent urgent corrective open heart surgery with cardiopulmonary bypass. Perioperative anesthetic management included prevention of tachycardia, atrial dysrhythmias and pulmonary hypertension, close monitoring for and prompt treatment of maternal hypotension, maintaining euvolemia and good cardiac contractility and avoiding hemodilution and hypothermia. These approaches, together with minimizing bypass time, resulted in successful maternal and fetal outcome. [Copyright &y& Elsevier]

Yak milk contains a greater percentage of protein and has better quality than bovine milk. There has been an increasing focus on yak milk and milk products during the last few years. In the present study, a PCR-based assay was developed for the specific identification of bovine milk in yak milk by designing 3 primers targeting the mitochondrial ND1 gene. The use of 3 primers in a single PCR reaction set yielded 2 amplification fragments of 293 and 190 bp from bovine milk DNA, whereas only 1 amplification fragment of 293 bp was obtained in yak milk DNA. The technique was applied to raw and heat-treated binary mixtures of yak and bovine milks and enabled the specific detection of bovine milk with a detection limit of 0.1%. The assay developed is sensitive, fast, and straightforward, and it might be useful in the quality control of yak milk and milk products. [ABSTRACT FROM AUTHOR]

Abstract: The interaction between fully nonlinear water waves in a wave tank and fixed or floating structures with vertical and flared side surfaces is investigated. The higher-order boundary element method is used to solve the mixed boundary value problem in an Eulerian formulation at each time step. The time stepping scheme updates the boundary conditions on the free water surface and body surface, based on a Lagrangian description. In order to increase the efficiency of the calculation, the domain decomposition technique is implemented, with continuity conditions enforced on the interface between adjacent subdomains by an iterative procedure. For the calculation of wave forces acting on structures, some auxiliary functions are used, instead of predicting the time derivative of the potential directly. By means of these auxiliary functions, the coupled fluid–structure interaction can be decoupled easily, so that the calculation of body motions becomes independent of the hydrodynamic force. In addition, mesh regridding using the Laplace smoothing technique and interpolation are applied on the free surface to avoid possible numerical instabilities. Numerical results are obtained for the wave interactions with vertical cylinders and flared structures at different wave numbers, in which the bodies are fixed, freely floating in one direction and totally freely floating, respectively. The effect of different flared shapes on the forces, wave run-up and body motions is also studied. [Copyright &y& Elsevier]

A PCR-single strand conformation polymorphism protocol has been developed for rapid genotyping of the yak g-casein gene. A total of 307 yaks from the Tianzhu White, Jiulong, Maiwa, and Datong breeds in China were genotyped at the κ-casein locus using the protocol developed in the present study. A polymorphism of κ-casein gene exon 4 has been identified in Tianzhu White breed by evaluating genomic DNA. The polymorphic site consists of a single nucleotide substitution G→C at position 362 of the exon 4, resulting in an AA substitution from Arg to Pro at position 121 of the AA sequence and in 2 alleles named, respectively, G and C based on nucleotide 362. The occurrence of allele C in the Tianzhu White breed was high with an allele frequency of 0.15. However, allele C appears to be absent in the yaks from Jiulong, Maiwa, and Datong breeds. [ABSTRACT FROM AUTHOR]

Abstract: The fully nonlinear regular and focused wave propagation and diffraction around a vertical circular cylinder in a numerical wave tank are investigated. The Mixed Eulerian–Lagrangian approach is used to update the moving boundary surfaces in a Lagrangian scheme, in which a higher-order boundary element method is applied to solve the wave field based on an Eulerian description at each time step. In order to increase the efficiency of the calculation, the domain decomposition technique is implemented, with continuity conditions enforced on the interface between adjacent subdomains by an iterative procedure. In this domain decomposition method, the top layers of elements at the interfaces are semi-discontinuous to avoid problems from the singularity. In addition, mesh regridding using the Laplace smoothing technique and interpolation are applied on the free surface to deal with possible numerical instability. Numerical results are obtained for the propagation of nonlinear regular waves and focused wave groups, and for the diffraction of such waves by a vertical cylinder. These results indicate that the present method employing the domain decomposition technique is very efficient, and can provide accurate results when compared with experimental data. [Copyright &y& Elsevier]

Summary: The severe acute respiratory syndrome (SARS) crisis led to the construction of a negative pressure operating theatre at a hospital in Hong Kong. It is currently used for treatment of suspected or confirmed airborne infection cases, and was built in anticipation of a return of SARS, an outbreak of avian influenza or other respiratory epidemics. This article describes the physical conversion of a standard positive pressure operating theatre into a negative pressure environment, problems encountered, airflow design, and evaluation of performance. Since entering regular service, routine measurements and observations have indicated that the airflow performance has been satisfactory. This has also been confirmed by regular air sampling checks. Computational fluid dynamics, a computer modelling technique, was used to compare the distribution of room air before and after the design changes from positive to negative pressure. The simulation results show that the physical environment and the dispersion pattern of bacteria in the negative pressure theatre were as good as, if not better than, those in the original positive pressure design. [Copyright &y& Elsevier]

Abstract: The application of a higher-order boundary element method in the numerical simulation of nonlinear waves radiated by a forced oscillating vertical circular cylinder is described. In this time-domain approach, the higher-order boundary element method is used to solve the mixed boundary value problem based on an Eulerian description at each time step. The 4th-order Runge–Kutta scheme is adopted to update the free water surface boundary conditions expressed in a Lagrangian formulation. For the calculation of hydrodynamic forces, some auxiliary functions are used instead of predicting the time derivative of the potential directly. In order to avoid wave reflection from the far-field boundary, an artificial damping layer is distributed on the outer part of the free surface. On the surfaces of the domain, the computational meshes are composed of unstructured triangular elements on the free surface, and quadrilateral elements elsewhere. Additionally, mesh regridding using the Laplace smoothing technique and interpolation are applied on the free surface to deal with possible numerical instability. Numerical results are obtained for a series of wave radiation problems, as well as for the interaction of an impulse wave with a circular cylinder in a circular tank. [Copyright &y& Elsevier]

The primary visual (V1), auditory (AI), and somatosensory (SI) cortices are reciprocally connected with their respective sensory association cortices. In the rat, we have previously demonstrated that some of the connections arising from the secondary somatosensory (SII) and parietal insular (PA) cortices and terminating in the SI, are characterized by the expression of latexin, a candidate protein of carboxypeptidase A inhibitor. Here, by using retrograde tracing and latexin-immunohistochemistry, we show that latexin-expressing neurons in other association cortices of different sensory modalities also contribute to the feedback projections to the corresponding primary sensory cortices. These are the lateral part of the secondary visual cortex (V2L), temporal association cortex, and the dorsal and ventral (AIIv) parts of the secondary auditory belt cortex. Within sublayer VIa of the V2L, AIIv and SII, the majority of the V1-, AI- and SI-projecting neurons respectively, are latexin-immunopositive. In contrast to feedback connections, far fewer latexin-expressing neurons participate in callosal or intrahemispheric feedforward connections. The latexin-expressing neurons constitute a virtually completely different population from corticothalamic neurons within the infragranular layers. Given that latexin might participate in the modulation of neuronal activity by controlling the protease activity, latexin-expressing feedback pathways would play a unique role in the modulation of sensory perception. [Copyright &y& Elsevier]

• The objective of our study is to correlate pathological and CT findings of 70 kidney cancer in order to determine the reliability of CT in kidney cancer and its extension. Our Moroccan context is experiencing an increase in the frequency of renal tumors. This trend can be explained by the generalization of the use of imaging, in particular abdominal ultrasound, which has become almost systematic among general practitioners (Godley and Ataga, 2000 1). The specificity of kidney cancer is anatomopathological heterogenicity: histological type, nuclear grade, tumor stage, these elements constitute the most important prognostic factors. Renal biopsy appears to be a safe and reliable solution with a low risk of tumor seeding and complications, however it cannot provide all the detailed histological information needed. Hence the interest in the abdominal scanner. The abdominal scanner is the reference examination for the evaluation of renal tumors, it diagnoses the tumor, specifies these characteristics, it assesses the loco regional, venous extension. The objective of our study is to correlate pathological and CT findings of 70 kidney cancer in order to determine the reliability of CT in kidney cancer and its extension. [ABSTRACT FROM AUTHOR]

The purpose of this study was to explore the conservative management for an unusual case of transnasal intracranial injury. A 3-year-old female child presenting with transnasal injuries after a domestic accident whereby she apparently fell while holding a large pair of scissors, which then penetrated her left nasal cavity, piercing her nasal cavity, ethmoid sinus, and skull base. The scissors were removed from her nasal cavity. The patient had scant cerebrospinal rhinorrhea and no other additional neurologic deficits noted at the time, as well as no long-term developmental deficits. This report highlights the occurrence of this rare condition. The role of radiologic studies such as computed tomographic scans and plain films in diagnosis and management of this case is affirmed. The strategy of minimally invasive treatment of this injury can be a reasonable treatment option. [ABSTRACT FROM AUTHOR]