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Objective:Application of Laryngeal Mask Airway (LMA) as a ventilation method has been rarely explored in short and medium period orthopedic operations. In this study, we evaluated ventilatory efficacy of LMA in patients admitted to Ho Chi Minh City Orthopedic and Rehabilitation Hospital, Vietnam via a number of patient indicators including changes of pulse, blood pressure, airway pressure, SpO2 and pressure of CO2 at the end of an exhaled breath (EtCO2). Method: A total of 154 emergency and elective surgery cases with anesthesia were selected for the study. Result: One minute after LMA insertion to discontinuation of anesthetic, we recorded slower pulse of patients but only twenty-six cases (16.9%) required intravenous administration of atropine. Blood pressure of patients dropped after 1 minute following LMA insertion but then recovered afterward and only nine cases (5.8%) needed administration of ephedrine. Conclusion: After surgery, only eleven (7.15%) patients experienced oral mucosal bleeding but no further special treatment was used. [ABSTRACT FROM AUTHOR]

This work proposes a novel composite adaptive controller based on the prescribed performance of the sliding surface and applies it to vibration control of a semi-active vehicle seat suspension system subjected to severe external disturbances. As a first step, the online fast interval type 2 fuzzy neural network system is adopted to establish a model and two sliding surfaces are used; conventional surface and prescribed surface. Then, an equivalent control is determined by assuming the derivative of the prescribed surface is zero, followed by the design of a controller which can guarantee both stability and robustness. Then, two controllers are combined and integrated with adaptation laws using the projection algorithm. The effectiveness of the proposed composite controller is validated through both simulation and experiment by undertaking vibration control of a semi-active seat suspension system equipped with a magneto-rheological (MR) damper. It is shown from both simulation and experimental realization that excellent vibration control performances are achieved with a small tracking error between the proposed and prescribed objectives. In addition, the control superiority of the proposed controller to conventional sliding mode controller featuring one sliding surface and proportional-integral-derivative (PID) controllers are demonstrated through a comparative work. [ABSTRACT FROM AUTHOR]

Operating photo‐induced reactions exclusively on catalyst surfaces while not exploiting the full catalyst volume generates a major footprint penalty for the photocatalytic reactor and leads to an inefficient use of the catalytic material. Photonic investigations clearly show that the solid foams have a strongly multidiffusive character, with photons being significantly trapped within the sample cores while addressing a photon mean free path lt = 20.1 ± 1.3 µm. This 3D process both greatly limits back‐reactions and promotes outstanding selectivity toward methane (around 80%) generation, and even ethane (around 18%) through C‐C coupling reaction, with residual carbon monoxide and dihydrogen contents (around 2%). Silica–titania TiO2@Si(HIPE) self‐standing macrocellular catalysts lead to optimal efficient thicknesses up to 20 times those of powders, thereby enhancing the way for real 3D‐photodriven catalytic processes above the millimeter scale and up to a 6 mm thickness. A rather simple Langmuir–Hinshelwood based kinetic model is proposed which highlights the strong dependence of photocatalytic reaction rates on light scattering and the crucial role on oxidation back‐reactions. In addition, a strong correlation between light attenuation coefficient and photon mean free path and median pore aperture diameter is demonstrated, offering thus a tool for photocatalytic behavior prediction.Novel TiO2@Si(HIPE) monolithic macrocellular foams offer a path for real 3D photodriven CO2 conversion at the millimeter thickness length scale, a configuration where “thicker is better” appears as a new paradigm. The light trapping scenario and the associated photoinduced electron within the foams both limit back‐reactions and promote outstanding selectivity toward methane, as well as ethane generation through the C‐C coupling reaction. [ABSTRACT FROM AUTHOR]

Science students increasingly need programming and data science skills to be competitive in the modern workforce. However, at our university (San Francisco State University), until recently, almost no biology, biochemistry, and chemistry students (from here bio/chem students) completed a minor in computer science. To change this, a new minor in computing applications, which is informally known as the Promoting Inclusivity in Computing (PINC) minor, was established in 2016. Here, we present the lessons we learned from our experience in a set of 10 rules. The first 3 rules focus on setting up the program so that it interests students in biology, chemistry, and biochemistry. Rules 4 through 8 focus on how the classes of the program are taught to make them interesting for our students and to provide the students with the support they need. The last 2 rules are about what happens "behind the scenes" of running a program with many people from several departments involved. [ABSTRACT FROM AUTHOR]

This paper carries out the static bending analysis of symmetric three-layer functionally graded sandwich beams, in which each layer is made from different functionally graded materials, and they are connected by shear connectors due to sliding movement. The finite element formulations are based on Timoshenko's first-order shear deformation beam theory (FSDT) and the finite element method to establish the equilibrium equation of beams. The calculation program is coded in the MATLAB environment, and then verification examples are given out to compare the numerical data of present work with those of exact open sources. The impact of several geometrical and material parameters on the mechanical response of the structure, such as the height-to-length ratio, boundary conditions, volume fraction index, and especially the shear coefficient of connectors, is being explored. When designing and using these types of structures in engineering practice, the computed results can be utilized as a valid reference. [ABSTRACT FROM AUTHOR]

• This research article investigates the use of pin–fin cooling in gas turbine blades, a crucial technique for managing extreme thermal conditions during operation. • It introduces a novel geometry, the C-shaped-recessed endwall, and explores its impact on pin–fin cooling channels. • The study reveals significant improvements in Heat Transfer Efficiency Index (HTEI) of up to 49.75 % compared to conventional flat endwalls, promising enhanced heat transfer capabilities in gas turbine blades. Pin-fin cooling has long been a crucial technique employed in gas turbine blades to manage the extreme thermal conditions experienced during operation. While numerous studies have investigated the heat transfer characteristics of different pin–fin configurations, the substantial impact of the endwall of the cooling channel on the heat transfer capability of turbine blades has not received adequate attention or thorough investigation. This research paper focuses on studying the influence of a novel geometry, termed C-shaped-recessed endwall, on pin–fin cooling channels in gas turbine blades. The primary objective of this investigation is to analyze the vortex formation and its impact on heat transfer characteristics within the cooling system. The study involved testing five different pin–fin arrays with C-shaped-recessed endwalls inserted between them, spanning a Reynolds number range of 7400 to 36000. The results show that with reference geometrical values, the new geometry increases the Heat Transfer Efficiency Index (HTEI) by 36.53 % compared to the flat endwall at Re = 29000. Higher heat transfer capacities were achieved by manipulating the C-shaped-recessed endwall heights and width of indentations, and the peak HTEI recorded an increase of 49.75 % at Re = 29000 compared to the flat endwall. The findings from this study underscore the potential of the C-shaped-recessed endwall geometry to improve the heat transfer capability of pin-fins by optimizing endwall configurations. [ABSTRACT FROM AUTHOR]