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Renal artery stenosis is responsible for approximately 75% of secondary hypertensive cases. A 63-year-old female patient with uncontrolled hypertension and other comorbidities including type 2 diabetes mellitus and knee osteoarthritis presented with drastically raised systolic blood pressure in this case report (220 mmHg). Bilateral abdominal bruits were detected upon of physical examination. Imaging investigation showed significant bilateral atherosclerotic renal artery stenosis. An optimal combination of antihypertensive agents mainly with an angiotensin converting enzyme inhibitor, other than interventional revascularization, was applied and resulted in controlled blood pressure.

A cell-free (CF) massive multiple-input-multiple-output (mMIMO) system can provide uniform spectral efficiency (SE) with simple signal processing. On the other hand, a recently introduced technology called hybrid relay-reflecting intelligent surface (HR-RIS) can customize the physical propagation environment by simultaneously reflecting and amplifying radio waves in preferred directions. Thus, it is natural that incorporating HR-RIS into CF mMIMO can be a symbiotic convergence of these two technologies for future wireless communications. This motivates us to consider an HR-RIS-aided CF mMIMO system to utilize their combined benefits. We first model the uplink/downlink channels and derive the minimum-mean-square-error estimate of the effective channels. We then present a comprehensive analysis of SE performance of the considered system. Specifically, we derive closed-form expressions for the uplink and downlink SE. The results reveal important observations on the performance gains achieved by HR-RISs compared to conventional systems. The presented analytical results are also valid for conventional CF mMIMO systems and those aided by passive reconfigurable intelligent surfaces. Such results play an important role in designing new transmission strategies and optimizing HR-RIS-aided CF mMIMO systems. Finally, we provide extensive numerical results to verify the analytical derivations and the effectiveness of the proposed system design under various settings.

This study investigates the integration of an intelligent reflecting surface (IRS) into an unmanned aerial vehicle (UAV) platform to utilize the advantages of these leading technologies for sixth-generation communications, e.g., improved spectral and energy efficiency, extended network coverage, and flexible deployment. In particular, we investigate a downlink IRS-UAV system, wherein single-antenna ground users (UEs) are served by a multi-antenna base station (BS). To assist the communication between UEs and the BS, an IRS mounted on a UAV is deployed, in which the direct links are obstructed owing to the complex urban channel characteristics. The beamforming at the BS, phase shift at the IRS, and the 3D placement of the UAV are jointly optimized to maximize the sum rate. Because the optimization variables, particularly the beamforming and IRS phase shift, are highly coupled with each other, the optimization problem is naturally non-convex. To effectively solve the formulated problem, we propose an iterative algorithm that employs block coordinate descent and inner approximation methods. Numerical results demonstrate the effectiveness of our proposed approach for a UAV-mounted IRS system on the sum rate performance over the state-of-the-art technology using the terrestrial counterpart.

Ground motion response spectra (GMRS) at rock/soil sites in regions where earthquake ground motions have dominant contents at high frequencies of 10 Hz or more are evaluated and the effects of soil amplification on the GMRS are studied. The seismic hazard levels at the soil sites are estimated from soil amplification functions and hazard curves for rock outcrop motions. The soil amplification functions are obtained using modified earthquake ground motions which match the uniform hazard response spectra (UHRS) for rock outcrop motions with various mean annual frequencies of exceedance in order to consider the effects of earthquake ground motions consistently in a site response analysis. UHRS at soil sites are determined from the calculated seismic hazard curves. Subsequently, design factors, which will be applied to UHRS, and the corresponding GMRS are evaluated such that the seismic risk for the structures, systems, and components of nuclear facilities would be equal to a target seismic risk. It can be observed from example applications that the UHRS and GMRS at soil sites have peaks at the natural frequencies of the soil, where the soil responses are amplified. Amplification at soil sites depends on the frequency contents of rock outcrop motions.

This research has used the L-band radar from ALOS-2 PALSAR-2 and field work data for evaluation of seasonal effects of backscattering intensity on retrieval forest biomass in the tropics. The effects of seasonality and HH, and HV polarizations of the SAR data on the biomass were analyzed. The dry season HV polarization could explain 61% of the biomass in this study region. The dry season HV backscattering intensity was highly sensitive to the biomass compared to the rainy season backscattering intensity. The SAR data acquired in the rainy season with humid and wet canopies were not very sensitive to the in situ biomass. Strong dependence of the biomass estimates with season of SAR data acquisition confirmed that the choice of right season SAR data is very important for improving the satellite based estimates of the biomass. This research expects that the results obtained in this research will contribute to monitoring of the quantity and quality of forest biomass in Vietnam and other tropical countries.

Reconfigurable intelligent surfaces (RISs) have recently gained significant interest as an emerging technology for future wireless networks. This paper studies an RIS-assisted propagation environment, where a single-antenna source transmits data to a single-antenna destination in the presence of a weak direct link. We analyze and compare RIS designs based on long-term and short-term channel statistics in terms of coverage probability and ergodic rate. For the considered optimization designs, closed-form expressions for the coverage probability and ergodic rate are derived. We use numerical simulations to analyze and compare against analytic results in finite samples. Also, we show that the considered optimal phase shift designs outperform several heuristic benchmarks., Comment: 5 pages, 1 figure. Submitted for publication

Because seismic waves are influenced by variability at local soil sites, their effects on the uniform hazard response spectra (UHRS) and ground motion response spectra (GMRS) of nuclear facilities at soil sites are studied by means of a probabilistic site response analysis based on the random vibration theory. Monte Carlo simulations are employed to take into consideration the effects of variability of the layer thickness, low-strain shear-wave velocity, and nonlinear dependence of the shear modulus and hysteretic damping on shear strain at soil sites. A new probabilistic model is proposed to simulate the variability of the layer thickness using an Erlang distribution. Random field models are considered for the nonlinear shear modulus reduction and damping curves. The probabilistic approach is applied to generic soil sites to evaluate their soil-amplification functions. The seismic hazard curves and the UHRS can be obtained using the amplification functions and the hazard curves of outcropping bedrock motions. Then, the seismic risk for structures installed at these types of sites is calculated and the resulting GMRS values for a seismic design are derived. It can be observed from the simulations that the variability in the layer thickness and the low-strain shear-wave velocity influences the soil-amplification functions and the resulting UHRS and GMRS values for the soil sites significantly. The effects increase with the variances of the considered random properties. Because the input motions for probabilistic earthquake response analyses of nuclear facilities are determined based on the UHRS/GMRS values, the effects of random soil sites must be carefully considered to ensure the seismic safety of these facilities.

Introduction. In advanced gastric cancer, preoperative chemotherapy is associated with survival benefit. FOLFIRI has demonstrated promising results in terms of survival and tolerance, especially in patients with poor performance status. Case Presentation. A 59-year-old male, diagnosed with pT4bN2M0 gastric cancer, underwent gastrointestinal anastomosis and three cycles of EOX chemotherapy. Due to disease progression, he was switched to FOLFIRI regimen. After 12 cycles, the patient received a subtotal gastrectomy and D2 lymphadenectomy. Microscopic examination achieved pCR, and the patient has been surviving 34 months without recurrence. No severe toxicities of chemotherapy were recorded. Conclusions. FOLFIRI might be a safe and effective option in neoadjuvant treatment for advanced gastric cancer among patients with poor performance status or progression after first-line chemotherapy.

In this paper, we investigate the spectral efficiency (SE) of a multi-user multiple-input multiple-output (MU-MIMO) antenna network in full-duplex (FD) regime, where uplink (UL) and downlink (DL) users simultaneously share the same time and frequency resources. Zero-forcing approach is applied efficiently to precode/detect signals in both UL and DL. To achieve the SE maximization, we formulate an optimized problem where the transmit power of Base station (BS) and users are jointly considered. Numerical results are used to show that the proposed algorithm may bring significant SE gain over the previous approaches under realistic channel conditions.

This paper presents the design of environmental monitoring and control system in aquaponics based on Internet of Things (IoT) technology. This system allows users to monitor and control the operation of devices through the application on smartphones, including: 3 water pumps, 3 air pumps, pH sensor, dissolved oxygen (DO) sensor, temperature sensor and humidity sensor, exhaust fan and misting. These devices are monitored and controlled in two modes: automatic and manual control. For 3 pumps and 3 air pumps, in automatic mode, allows the user to set the pump time between water pumps and between air pumps. In manual control mode, allows the user to control water pumps and air pumps by the push of a button on a smartphone application. Monitor pH, DO and allows the user to set the pH threshold and DO threshold to give an alert when the pH and DO exceed the threshold. Monitor the parameters of temperature, humidity in the membrane house and allow setting the temperature threshold and humidity threshold to control the exhaust fan and misting respectively when the temperature and humidity exceed the threshold. This system tested at aquaponics farm - Dong Thap Aqua. The results show that this system is working reliably and promising which brings significantly benefits to aquaponics. Besides, it also contributes to improve production efficiency and sustainable development of green agriculture.

This paper presents a detailed analysis, design and simulation of PCI Express Physical Layer. The Physical Layer isolates the Transaction and Data Link Layers from the signaling technology used for Link data interchange. The Physical Layer is divided into the logical and electrical subblocks. The paper designed Physical Layer in the system level with top-down design method and wrote the Verilog HDL codes to implement Physical Layer. Wrote testbench to verify the correctness of the design module for function simulation. The simulation results show that the designed Physical Layer meets the required of the function of PCI Express™ Physical layer Base Specification Revision 2.0.

Recently, novel materials such as semiconductor metal oxide (SMO) nanowires (NWs), carbon nanotubes (CNTs), and hybrid materials SMO/CNTs have been attractively received attention for gas sensing applications. These materials are potential candidates for improving the well known “3S”: Sensitivity, Selectivity and Stability. In this article, we describe our recent studies on synthesis and characterizations of nanomaterials for gas-sensing applications. The focused topics include are: (i) various system of hybrid materials made CNTs and SMO; and (ii) quasi-one-dimension (Q1D) nanostructure of SMO materials. The synthesis, characterizations and gas-sensing properties are deal thoroughly. Gas-sensing mechanism of those materials, possibility producing new novel materials and other novel applications are also discussed

This paper provides empirical evidence relating to the characteristics of firms adopting ABC compared to those not adopting ABC. The empirical evidence is based on responses received from 120 manufacturing companies. The characteristics explored relate to what are referred to as firm characteristic and business environment variables which are defined as those relating to: cost structure, production complexity, production diversity, firm size and the level of competitive intensity. Five hypotheses are developed from a discussion of the literature relating to adoption issues. The results suggest that there would appear to be significant differences between firms adopting ABC and those not adopting ABC in relation to production complexity, firm size and level of competitive intensity, while there would appear to be no significant differences in relation to the proportion of overhead costs in total manufacturing costs and production diversity.