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ABSTRACT: Left ventricular diverticulum is a rare congenital left ventricular outpouchings. The disease is often diagnosed during childhood because it is frequently associated with midline thoracoabdominal defects and other congenital cardiac anomalies. Most cases are asymptomatic, often discovered incidentally. Some complications have been reported including infarction, arrhythmia, heart failure. The most severe complication is rupture of the diverticulum, which can cause a patient's death. Therefore, this congenital defect should be detected early to assess potential risks for appropriate treatment. In this article, we report a case of a 3-month-old boy with left ventricular diverticulum diagnosed with Doppler ultrasound and cardiac MSCT. Complete resection was undertaken. The patient remained asymptomatic with good heart function 2 months after surgery.

The ultrasound-assisted extraction (UAE) was conducted using the stainless steel (SS) and polyether ether ketone (PEEK) columns and analyzed with high-performance liquid chromatography (HPLC) to understand the mechanism of ultrasound-assisted chromatography (UAC). Empty SS and PEEK columns were used to extract dyes from a fabric under identical conditions with several parameters including the initial ultrasonic bath temperatures (30 °C and 40 °C), ultrasound power intensities (0, 20, 40, 60, 80, and 100 %), ultrasound operation modes (normal and sweep), and ultrasound frequencies (25 kHz, 40 kHz, and 132 kHz) to compare their extraction capabilities. After 30 min of extraction, the amount of extract was determined by HPLC. The PEEK material was significantly affected by ultrasonic radiation compared to the SS material, especially at a higher temperature (40 °C), power intensity (100 %), and frequency (132 kHz) with sweep mode. At a maximum power density of 45 W/L, the extraction effectiveness ratio of PEEK to SS was in the range of 1.8 - 3.9 depending on the specific frequency, initial temperature, and with or without temperature control. The most optimal ultrasound frequencies, in terms of enhancing extraction effectiveness, are in the order of 132 kHz, 40 kHz, and 25 kHz. Unlike the SS material, the PEEK material was more affected by temperature and acoustic effects under identical conditions, especially at 132 kHz ultrasound frequency. In contrast, at lower frequencies of 40 kHz and 25 kHz, no significant differences in the acoustic effects were observed between the PEEK and SS materials. The findings of this study contribute to elucidating the roles of column materials in UAE and UAC.

This study presents a new asymmetric junctionless tunnel field-effect transistor (AJ-TFET) to scale TFETs into sub-10-nm regimes. The asymmetric junctionless p+ source/body and junctional n/p+ drain/body separately optimize the lateral source and drain coupling to efficiently switch the TFETs, producing an abrupt on-off switching. Because of n-drain/p+body junction, the off-state tunnel barrier can be extended into the drain, ensuring an excellent short-channel effect without the limitation of channel lengths. Si/Ge heterojunctions and high-k gate insulators are combined with the AJ-TFETs for additional on-current boosting. Using compact structures and feasible parameters from practical Si-based CMOS technologies, the advancement in the on-off switching and short-channel effect make the AJ-TFET highly promising as an ideal approach into the sub-10-nm regimes.

We investigate the numerical approximation of integrals over |$\mathbb{R}^{d}$| equipped with the standard Gaussian measure |$\gamma $| for integrands belonging to the Gaussian-weighted Sobolev spaces |$W^{\alpha }_{p}(\mathbb{R}^{d}, \gamma)$| of mixed smoothness |$\alpha \in \mathbb{N}$| for |$1 < p < \infty $|⁠. We prove the asymptotic order of the convergence of optimal quadratures based on |$n$| integration nodes and propose a novel method for constructing asymptotically optimal quadratures. As for related problems, we establish by a similar technique the asymptotic order of the linear, Kolmogorov and sampling |$n$| -widths in the Gaussian-weighted space |$L_{q}(\mathbb{R}^{d}, \gamma)$| of the unit ball of |$W^{\alpha }_{p}(\mathbb{R}^{d}, \gamma)$| for |$1 \leq q < p < \infty $| and |$q=p=2$|⁠. [ABSTRACT FROM AUTHOR]

In the present paper, we study the analyticity of the leftmost eigenvalue of the linear elliptic partial differential operators with random coefficient and analyse the convergence rate of the quasi-Monte Carlo method for approximation of the expectation of this quantity. The random coefficient is assumed to be represented by an affine expansion $ a_0({\boldsymbol {x}})+\sum _{j\in {\mathbb N}}y_ja_j({\boldsymbol {x}}) $ a 0 (x) + ∑ j ∈ N y j a j (x) , where elements of the parameter vector $ {\boldsymbol {y}}=(y_j)_{j\in {\mathbb N}}\in U^\infty $ y = (y j) j ∈ N ∈ U ∞ are independent and identically uniformly distributed on $ U:=[-\frac {1}{2},\frac {1}{2}] $ U := [ − 1 2 , 1 2 ]. Under the assumption $ \|\sum _{j\in {\mathbb N}}\rho _j|a_j|\|_{L_\infty (D)} ‖ ∑ j ∈ N ρ j | a j | ‖ L ∞ (D) < ∞ with some positive sequence $ (\rho _j)_{j\in {\mathbb N}}\in \ell _p({\mathbb N}) $ (ρ j) j ∈ N ∈ ℓ p (N) for $ p\in (0,1] $ p ∈ (0 , 1 ] we show that for any $ {\boldsymbol {y}}\in U^\infty $ y ∈ U ∞ , the elliptic partial differential operator has a countably infinite number of eigenvalues $ (\lambda _j({\boldsymbol {y}}))_{j\in {\mathbb N}} $ (λ j (y)) j ∈ N which can be ordered non-decreasingly. Moreover, the spectral gap $ \lambda _2({\boldsymbol {y}})-\lambda _1({\boldsymbol {y}}) $ λ 2 (y) − λ 1 (y) is uniformly positive in $ U^\infty $ U ∞ . From this, we prove the holomorphic extension property of $ \lambda _1({\boldsymbol {y}}) $ λ 1 (y) to a complex domain in $ {\mathbb C}^\infty $ C ∞ and estimate partial derivatives of $ \lambda _1({\boldsymbol {y}}) $ λ 1 (y) with respect to the parameter $ {\boldsymbol {y}} $ y by using Cauchy's formula for analytic functions. Based on these bounds we prove the dimension-independent convergence rate of the quasi-Monte Carlo method to approximate the expectation of $ \lambda _1({\boldsymbol {y}}) $ λ 1 (y). [ABSTRACT FROM AUTHOR]

This paper introduces a controller unit for reactivity monitoring and automatic power control that was designed and constructed for the 500 kW Dalat Nuclear Research Reactor (DNRR). For power control and reactivity calculations, frequency signals from neutron measurement channels of starting and working ranges of the reactor are used. Two abovementioned independent functions were combined in an Artix-7 FPGA board for determining reactivity values by solving the point reactor kinetics equations with six delayed neutron groups and for stabilizing the reactor power at preset levels by determining the unbalance voltage signal to control the automatic control rod. With real-time calculations, the newly developed controller can monitor the reactor reactivity and control the reactor power online. The developed controller unit's reactivity measuring and power stabilizing capabilities were assessed using the DNRR in normal operation and assumed emergency conditions and compared with those of the preexisting imported BNO-102R1 module of the DNRR control and protection system, known as ASUZ-14R. The results of the experiments show that the produced FPGA-based unit and the BNO-102R1 unit have the same technical characteristics and features, with the disparities being less than 5% and 1%, respectively, in reactivity measurement and power stabilization. The experimental data of reactivity measurements by the FPGA-based unit and the calculation results were also compared and found that the relative deviations between those are also less than 10%. The developed controller unit is capable of carrying out a variety of training and operational experiments on the DNRR. [ABSTRACT FROM AUTHOR]

The problem of recovering a diffusion coefficient a in a second-order elliptic partial differential equation from a corresponding solution u for a given right-hand side f is considered, with particular focus on the case where f is allowed to take both positive and negative values. Identifiability of a from u is shown under mild smoothness requirements on a, f, and on the spatial domain D, assuming that either the gradient of u is nonzero almost everywhere, or that ff as a distribution does not vanish on any open subset of D. Further results of this type under essentially minimal regularity conditions are obtained for the case of D being an interval, including detailed information on the continuity properties of the mapping from u to a. [ABSTRACT FROM AUTHOR]

The purpose of the present paper is to investigate the decay of Bernstein numbers of the embedding from [ABSTRACT FROM AUTHOR]

This paper presents a systematic synthesis procedure for generating universal voltage-mode biquadratic filters based on the nodal admittance matrix expansion. The obtained eight equivalent circuits can realize all five standard filter functions namely lowpass, bandpass, highpass, notch and allpass employing only two active elements. The obtained circuits offer the following advantages: five inputs and two outputs, simple circuit configuration, orthogonal controllability between pole frequency and quality factor, and low active and passive sensitivities. The workability of some synthesized filters is verified by HSPICE simulations to demonstrate the usefulness of the proposed method.

Mục tiêu chính của nghiên cứu này là khảo sát các yếu tố ảnh hưởng đến quá trình chưng cất tinh dầu gừng như thời gian lưu trữ (để héo) và thời gian chưng cất. Bên cạnh đó, ảnh hưởng của phương pháp chưng cất đến giá trị cảm quan và các thông số hóa-lý của tinh dầu gừng cũng được tiến hành đánh giá. Kết quả nhận thấy gừng sau khi thu hoạch được lưu trữ 4 ngày và chưng cất trong thời gian 16 giờ bằng phương pháp lôi cuốn hơi nước hay 80 phút khi có sự hỗ trợ của vi sóng với công suất 300W là phù hợp về hiệu suất và chất lượng của tinh dầu thu được. Chất lượng tinh dầu và hàm lượng các cấu phần có trong tinh dầu gừng thì phụ thuộc vào phương pháp chưng cất. Các cấu phần chính trong tinh dầu gừng thu được từ hai phương pháp chưng cất trên gồm Neral (13,99-24,04%), Zingiberene (10,62-10,88%), alpha-Farnesene (7,3-8,05%), Nerol (6-7,09%) và beta- Sesquiphellandrene (5,31-5,37%).