bluuebunny/crossref_metadata_2025 huggingface dataset:
A Novel Topology to Improve PV Module Efficiency under Partial Shading Conditions
Authors: Bonkoungou Dominique , Guingane Toussaint , Korsaga Eric , Tassembedo Sosthène , Koalaga Zacharie , Darga Arouna , Zougmore François
Published: July 2022

In this paper, we investigate the power degradation in a novel photovoltaic (PV) cell reconfiguration named KenDoKu (KDK) topology under different shading patterns. We analyze how a modification in the linkage between the PV cells within a shaded PV module can affect its effectiveness. The proposed approach relocates the physical position of the PV cells within the PV module without any change in electrical connections and redistributes the shading effects over the PV module for the improvement of the power generation. To achieve this purpose, modeling and simulation are performed for a set of various shading patterns such as homogeneous, sectional, and scattered shadings. The simulation model used is a combination of two-diode model and Bishop’s model. This model is applied to a PV module and is implemented in LTSpice software to quantify the impact of shading on P-V characteristics. The performance of the KDK topology is compared to other optimized configurations such as total-cross-tied (TCT), bridge link-total cross tied (BL-TCT), honey comb-bridge link (HC-BL), series parallel-total cross tied (SP-TCT) and existing odd-even (OE) and Latin square (LS) schemes of interconnection. The effectiveness of the KDK approach is evaluated in terms of the characteristics of P-V curves, global maximum power (GMP), mismatch power loss MPL (%), fill factor FF (%), and performance ratio PR (%). The simulated results revealed that the KDK configuration scheme performs better in terms of generating maximum power under the considered partial shading conditions. The proposed approach reduces the maximum power losses (MPL) and improves the fill factor (FF) with respect to OE and LS configurations in the most of the cases. Moreover, experimental verification is also carried out. The obtained results show that the KDK configuration outperforms the other analyzed PV cell rearrangement in terms of increased power.
Improper Estimation of Thermodynamic Parameters in Adsorption Studies with Distribution Coefficient KD (qe/Ce) or Freundlich Constant (KF): Considerations from the Derivation of Dimensionless Thermodynamic Equilibrium Constant and Suggestions
Authors: Tran Hai Nguyen
Published: July 2022

Adsorption processes often include three important components: kinetics, isotherm, and thermodynamics. In the study of solid–liquid adsorption, “standard” thermodynamic equilibrium constant [Formula: see text]; dimensionless) plays an essential role in accurately calculating three thermodynamic parameters: the standard Gibbs energy change (∆ G°; kJ/mol), the standard change in enthalpy (∆ H°; kJ/mol), and the standard change in entropy [∆ S°; J/(mol × K)] of an adsorption process. Misconception of the derivation of the [Formula: see text] constant that can cause calculative errors in values (magnitude and sign) of the thermodynamic parameters has been intensively reflected through certain kinds of papers (i.e., letters to editor, discussions, short communications, and correspondence like comment/rebuttal). The distribution coefficient ( K D) and Freundlich constant ( K F) have been intensively applied for calculating the thermodynamic parameters. However, a critical question is whether K D or K F is equal to [Formula: see text]. This paper gives (1) thorough discussion on the derivation of thermodynamic equilibrium constant of solid–liquid adsorption process, (2) reasonable explanation on the inconsistency of (direct and indirect) application of K D or K F for calculating the thermodynamic parameters based on the derivation of [Formula: see text], and (3) helpful suggestions for improving the quality of papers published in this field.
Bioconjugation of Fluorescent Gold Nanoparticles Synthesized Using Marine Brown Algae Sargassum longifolium
Authors: Rajeshkumar S. , Sellami Hanen , Ali Daoud , Chitra S. , Ponnanikajamideen M. , Arunachalam Kalirajan
Published: July 2022

In the present study, fluorescent gold nanoparticles (Flu Au‐NPs) were synthesized via simple and ecofriendly green route using extract of brown algae Sargassum longifolium (S. longifolium). Characterization of synthesized Au‐NPs was undertaken. The characteristic absorption peak of Au‐NPs was in range 530 nm in UV‐vis spectrum. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) allow the visualization of the morphological and structural character of Au‐NPs. The mean particle size was calculated to be 17‐50 nm. Energy dispersive X‐ray spectroscopy analysis (EDAX) confirmed the presence of pure gold in the synthesized Au‐NPs. The X‐ray diffraction (XRD) pattern showed the face‐centered cubic (FCC) nature of Au‐NPs. Fourier transform infrared spectrometer (FT‐IR) showed the characteristic peaks of different biocomponents in the brown algae S. longifolium extract which acted as stabilizing or capping agents of Au‐NPs.
Analytical Solution of One-Dimensional Nonlinear Conformable Fractional Telegraph Equation by Reduced Differential Transform Method
Authors: Deresse Alemayehu Tamirie
Published: July 2022

In this paper, the reduced differential transform method (RDTM) is successfully implemented to obtain the analytical solution of the space-time conformable fractional telegraph equation subject to the appropriate initial conditions. The fractional-order derivative will be in the conformable (CFD) sense. Some properties which help us to solve the governing problem using the suggested approach are proven. The proposed method yields an approximate solution in the form of an infinite series that converges to a closed-form solution, which is in many cases the exact solution. This method has the advantage of producing an analytical solution by only using the appropriate initial conditions without requiring any discretization, transformation, or restrictive assumptions. Four test modeling problems from mathematical physics, conformable fractional telegraph equations in which we already knew their exact solution using other numerical methods, were taken to show the liability, accuracy, convergence, and efficiency of the proposed method, and the solution behavior of each illustrative example is presented using tabulated numerical values and two- and three-dimensional graphs. The results show that the RDTM gave solutions that coincide with the exact solutions and the numerical solutions that are available in the literature. Also, the obtained results reveal that the introduced method is easily applicable and it saves a lot of computational work in solving conformable fractional telegraph equations, and it may also find wide application in other complicated fractional partial differential equations that originate in the areas of engineering and science.
Max-EWMA Chart Using Beta and Simplex Distributions for Time and Magnitude Monitoring
Authors: Ali Sajid , Akram Muhammad Farhan , Shah Ismail
Published: July 2022

Control charts are used to detect assignable causes in different manufacturing and nonmanufacturing processes. This study presents a new maximum exponentially weighted moving average (Max-EWMA) chart for joint unit interval time and magnitude monitoring. To this end, beta distribution is considered for time whereas simplex distribution is used for magnitude. Average run length (ARL), standard deviation of run length (SDRL), and different quantiles are used to evaluate the performance of the Max-EWMA chart. A real data example is also included in the study to show the application of the proposed chart. The results provide evidences that the Max-EWMA chart is efficient in detecting small- to medium-sized shifts.
Comparison between the Right and Left Distal Radial Access for Patients Undergoing Coronary Procedures: A Propensity Score Matching Analysis
Authors: Rivera Kristian , Fernández-Rodríguez Diego , Casanova-Sandoval Juan , Barriuso Ignacio , Zielonka Marta , Pueyo-Balsells Nuria , Calaf Valls Immaculada , Worner Fernando
Published: July 2022

Introduction. Distal radial access for coronary procedures decreases hemostasis time, prevents radial occlusion, and improves patient comfort compared to conventional transradial access. Initially described for left distal radial access (lDRA), the right distal radial access (rDRA) is feasible. However, there are no comparative studies to date. This study aimed to evaluate the impact of the access site on vascular access and procedural performance. Methods. From August 2020 to October 2021, coronary procedures performed through distal radial access were prospectively recorded. After propensity score matching, the rDRA and lDRA were compared. The primary endpoint was the proportion of approach success. The secondary endpoints included access time, coronary procedural success, radial spasm, exposition to ionizing radiation, patient comfort, and vascular access-related complications. Results. From a total of 385 procedures in 382 patients, after a propensity score matching, 182 procedures were compared between the rDRA and lDRA. There were no differences in the baseline characteristics between the groups. Compared to the lDRA, the rDRA presented similar approach success (96.7% vs. 96.7%,

p
=
1.0

), less access time (39 (25–60) sec vs. 50 (29–90) sec,

p
=
0.018

), comparable coronary procedural success after sheath placement (100% vs. 100%,

p
=
1.000

), and not statistically significant radial spasm (2.19% vs. 6.59%,

p
=
0.148

). No differences in dose-area product (32 (20–56.2) Gy.m2 vs. 32.3 (19.4–46.3) Gy.m2;

p
=
0.472

) and fluoroscopy time (4.4 (2.5–9.1) min vs. 4.3 (2.4–7.5) min,

p
=
0.251

) were detected between the groups. No vascular access-related complications were observed in any group. Conclusions. The rDRA, compared to the lDRA, had the same proportion of approach success and procedural performance, with a slight reduction in access time for patients undergoing coronary procedures.
lncRNA MALAT1 Promotes Diabetic Nephropathy Progression via miR-15b-5p/TLR4 Signaling Axis
Authors: Yang Zijun , Song Dongxu , Wang Yulin , Tang Lin
Published: July 2022

Objective. The long noncoding RNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) are closely associated with the pathogenesis of diabetic nephropathy (DN). But a complete mechanism for MALAT1 in DN has yet to be identified. This study investigated the effect of MALAT1 on DN through the regulation of miR-15b-5p/TLR4 signaling. Method. Renal tissues were collected from DN patients. Human renal tubular epithelial cells (HK-2) were used as a model of DN induced by high glucose (HG). We then measured the viability, apoptosis, and inflammatory cytokine levels of HK-2 cells using the corresponding assays. Following transfections of si-MALAT1, si-MALAT1+miR-15b-5p inhibitor, or si-MALAT1+vector TLR4 into HG-stimulated HK-2 cells, cell viability, apoptosis, and inflammatory cytokines were again measured. Furthermore, dual-luciferase reporter assay validated the interactions of MALAT1/miR-15b-5p and miR-15b-5p/TLR4. In addition, the interaction between MALAT1 and miR-15b-5p was investigated by RNA immunoprecipitation (RIP). Results. A significant upregulation of MALAT1 was observed in DN kidney tissues, as well as in HG-stimulated HK-2 cells. MALAT1 knockdown attenuates the inhibition of cell viability, apoptosis, and inflammatory response induced by HG in HK-2 cells. Moreover, a miR-15b-5p inhibitor or TLR4 overexpression reversed the above effects induced by MALAT1 knockdown. Conclusion. These results indicate that reduced MALAT1 ameliorates HG-stimulated HK-2 cell damage through an inhibition of the miR-15b-5p/TLR4 axis. MALAT1 may serve as a biomarker and potential therapeutic target for DN.
Correlation of Glucose and Lipid Metabolism Levels and Serum Uric Acid Levels with Diabetic Retinopathy in Type 2 Diabetic Mellitus Patients
Authors: Li Tiantian , Wu Yan
Published: July 2022

Objective. The aim of this study was to observe the association between the development of diabetic retinopathy (DR) in type 2 diabetes mellitus (T2DM) and the levels of glucose and lipid metabolism and serum uric acid (SUA) levels. Methods. A retrospective analysis was performed on 97 patients with T2DM who were admitted to our endocrinology department from June 2019 to April 2021 with complete data; the patients were divided into DR and no DR groups (NDR) according to the presence or absence of DR. Their clinical history and biochemical test indexes were collected, and the fundus was examined by fundus photography and the fundoscopic examination method, and the vascular diameter was measured by using a computer software. All clinical data, medical history, and biochemical test indexes were compared between the two groups, and logistic regression was used to analyze the risk factors of DR. Results. The duration of DM disease, fasting blood glucose (FBG), glycosylated hemoglobin, type A1C (HbA1c) levels, cholesterol (TC), triacylglycerol (TG), low-density lipoprotein cholesterol (LDL-C), and SUA levels were higher in the DR group than those in the NDR group, and the differences were significant (P<0.05). The difference between the NDR group and the DR group in terms of gender, age, BMI, DBP, SBP, family history of DM, FINS, and HDL-C levels was not significant (P>0.05). The results of multifactorial analysis showed that the four variables of DM duration, HbA1c, TG, and SUA were still risk factors for the development of DR (P<0.05). Further receiver operating characteristic (ROC) analysis showed that the areas under the curves (AUCs) for the duration of DM disease, HbA1c, TG, and SUA to predict the occurrence of DR were 0.740 (95% CI 0.639–0.841), 0.767 (95% 0.672–0.862), 0.721 (95% CI 0.617–0.826), and 0.693 (95% CI 0.588∼0.797), respectively. Conclusion. The lesions of DR in T2DM patients have a close relationship with the course of DM, HbA1c, TG, and SUA, and the course of DM, HbA1c, TG, and SUA has a good predictive value for the occurrence of DR.
In Vitro and In Vivo Antioxidant and Anticancer Potentials of Royal Jelly for Dimethylhydrazine-Induced Colorectal Cancer in Wistar Rats
Authors: Shakib Khoob Maede , Hosseini Seyed Mohammad , Kazemi Sohrab
Published: July 2022

Background and Objective. Royal jelly (RJ) is one of the well-known natural substances exhibiting great anticancer and antioxidant activities. Methods. This study was conducted among 60 rats, and groups consist of control, three separate groups for RJ, dimethylhydrazine (DMH), and vitamin E, and two separate treated groups with DMH + RJ and DMH + vitamin E. Additionally, the cytotoxicity of royal jelly was examined on HT-29 cell line. Findings. Based on the in vitro assessment using MTT assay, the LC50 of royal jelly was 1.781 mg/ml, and the highest cytotoxicity was observed at 25 mg/ml concentration after 48 hours. Meanwhile, in the in vivo study, after the 13th week, compared to the DMH group, the rats exposed to DMH + royal jelly experienced a significant less oxidative stress (

P
<
0.05

) and a significantly greater total antioxidant capacity (TAC) level (

P
<
0.05

). The expression of proliferating cell nuclear antigen (PCNA), platelet-derived growth factor (PDGF), and carcinoembryonic antigen (CEA) proteins significantly decreased among the animals receiving DMH + royal jelly compared to the DMH group. The pathological examinations revealed less congestion, necrosis, inflammation, and cell proliferation in the colon tissue of the RJ-treated group than that of the DMH group. Overall, the biochemical indices were better in the treatment groups in comparison with the DMH group. Conclusion. The results represented the clinical usability of royal jelly, as a substance with anticancer properties, to prevent and treat colorectal cancer. This issue is related to its effective antioxidant potential, which even exhibits more effectiveness than the vitamin E, which is known as a strong antioxidant.
The Influence of Medical Comorbidities on Survival Disparities in a Multiethnic Group of Patients with De Novo Metastatic Breast Cancer
Authors: Wallner Lauren P. , Chen Lie H. , Hogan Tiffany A. , Brasfield Farah M. , Haque Reina
Published: July 2022

Background:

The influence of common medical comorbidities on mortality and racial/ethnic disparities in mortality among women with metastatic breast cancer remains largely unknown.

Methods:

In this longitudinal study, women with newly diagnosed stage IV breast cancer were identified in a large, diverse, integrated healthcare delivery system from January 2009 to December 2017 (n = 995) and followed through December 31, 2018, for all-cause (overall) and breast cancer–specific mortality via electronic health records. We computed overall and breast cancer–specific mortality rates by race/ethnicity and Elixhauser comorbidity index (ECI). Multivariable-adjusted hazard ratios (HR) assessing the influence of race/ethnicity and comorbidity status on overall and breast cancer–specific mortality were estimated using proportional hazards regression adjusted for age, breast cancer subtype, geocoded income, and palliative cancer treatments.

Results:

Nearly 17% of this cohort had diabetes and 45% had hypertension. Overall, 644 deaths occurred in the cohort (median follow-up time of 1.8 years), of which 88% were breast cancer related. The risk of overall mortality was increased in Asian/Pacific Islander (PI; adjusted HR = 1.45; 95% CI, 1.10–1.92) and African American/Black women (adjusted HR = 1.34; 95% CI, 1.02–1.76) when compared with white women. Women with more comorbidities (ECI ≥ 5) had more than 3-fold higher overall mortality rate than those without any comorbidities [602/1,000 person-year (PY) vs. 175/1,000 PY]. Similar associations were found for breast cancer–specific mortality.

Conclusions:

Medical comorbidities are associated with an increased risk of overall mortality among women with de novo metastatic disease and may influence racial/ethnic disparities in mortality.

Impact:

Optimizing the management of medical comorbidities in metastatic breast cancer patients may also help reduce disparities in breast cancer–related mortality.
HPV DNA as a Biomarker in Oropharyngeal Cancer: A Step in the Right Direction
Authors: Colevas A. Dimitrios
Published: July 2022

Lack of prospectively planned follow-up and minimal characterization of the patient population studied complicate interpretation of circulating human papillomavirus (HPV) DNA as a prognostic biomarker for patients with HPV-associated oropharyngeal carcinoma treated with curative intent.

See related article by Berger et al., p. 4292
Using CD69 PET Imaging to Monitor Immunotherapy-Induced Immune Activation
Authors: Edwards Kimberly J. , Chang Bryan , Babazada Hasan , Lohith Katheryn , Park Daniel H. , Farwell Michael D. , Sellmyer Mark A.
Published: July 2022

Immune checkpoint inhibitors (ICI) have been effective in treating a subset of refractory solid tumors, but only a small percentage of treated patients benefit from these therapies. Thus, there is a clinical need for reliable tools that allow for the early assessment of response to ICIs, as well as a preclinical need for imaging tools that aid in the future development and understanding of immunotherapies. Here we demonstrate that CD69, a canonical early-activation marker expressed on a variety of activated immune cells, including cytotoxic T cells and natural killer (NK) cells, is a promising biomarker for the early assessment of response to immunotherapies. We have developed a PET probe by radiolabeling a highly specific CD69 mAb, H1.2F3, with Zirconium-89 (89Zr), [89Zr]-deferoxamine (DFO)-H1.2F3. [89Zr]-DFO-H1.2F3 detected changes in CD69 expression on primary mouse T cells in vitro and detected activated immune cells in a syngeneic tumor immunotherapy model. In vitro uptake studies with [89Zr]-DFO-H1.2F3 showed a 15-fold increase in CD69 expression for activated primary mouse T cells, relative to untreated resting T cells. In vivo PET imaging showed that tumors of ICI-responsive mice had greater uptake than the tumors of nonresponsive and untreated mice. Ex vivo biodistribution, autoradiography, and IHC analyses supported the PET imaging findings. These data suggest that the CD69 PET imaging approach detects CD69 expression with sufficient sensitivity to quantify immune cell activation in a syngeneic mouse immunotherapy model and could allow for the prediction of therapeutic immune responses to novel immunotherapies.
OPRM1-ROS1 Fusion Detected by Next-Generation Sequencing with Circulating DNA in a Patient with EGFR Mutated Advanced NSCLC: A Case Report
Authors: Zhang Sicai , Xu Zhiyong , Zhang Weimin
Published: July 2022

ROS1 comprises a small molecular subset of NSCLC, and several fusion partners have been discovered. Concomitant mutations of EGFR and ROS1 in NSCLC have been occasionally reported, while no clear standard of treatment has been revealed. Here we report a case with metastatic lung adenocarcinoma detected to have EGFR 21 exon L858R mutation at diagnosis, who responded to first-line gefitinib and second-line osimertinib treatment. Next-generation sequencing during the treatment course revealed multiple alterations, including an OPRM1-ROS1 Ointergenic: R36 fusion. We reviewed the related literatures but found no report of this fusion type previously. The application of ctDNA detection results in the finding of new alterations, which need further confirmation.
One-Stage Flexible Ureteroscopy during Single-Tract Percutaneous Nephrolithotomy in the Treatment of Parallel Calyceal Stones
Authors: Zhou Zhe , Li Yang , Chen Yutong , Shang Zhiqun , Niu Yuanjie
Published: July 2022

Introduction: The aim of this study was to compare the clinical safety and efficiency between one-stage flexible ureteroscopy (FURS) during single-tract percutaneous nephrolithotomy (PCNL) and multi-tract PCNL in the treatment of parallel calyceal stones. Methods: One hundred and twenty-five patients who had calyceal stones parallel to puncture channel from March 2017 to January 2021 were enrolled and assigned into two groups. Seventy cases received the treatment of FURS combined with single-tract PCNL under the oblique supine position (the Combined group), and 55 cases had multi-tract PCNL procedure under the prone position (the Multi-tract group). Demographic characteristics, clinical information, and surgical outcomes were analyzed. Results: Demographic variables and stone characteristics did not show statistical difference between the two groups. Compared with the Multi-tract group, there were longer operation time (p = 0.021), shorter postoperative hospitalization days (p = 0.003), smaller postoperative hemoglobin drop (p = 0.002), less incidence of moderate and severe postoperative pain (p = 0.001), and postoperative perirenal hematoma (p = 0.012) in the Combined group. No significant difference was found in the stone-free rate (SFR) and postoperative fever between the two groups (p = 0.880 and p = 0.324). More patients needed postoperative intervening embolization in the Multi-tract group (p = 0.048). Discussion/Conclusions: For most patients with parallel calyceal stones, one-stage FURS combined with single-tract PCNL procedure was a safer procedure for the reduction of complications and could achieve a comparative SFR compared to the multi-tract PCNL.
Performance analysis on self organization based clustering scheme for FANETs using K-means algorithm and firefly optimization
Authors: Pulhani Yashu , Kang Ankur Singh , Sharma Vishal
Published: July 2022

With the fast-increasing development of wireless communication networks, unmanned aerial vehicle (UAV) has emerged as a flying platform for wireless communication with efficient coverage, capacity, reliability, and its network is called flying ad-hoc network (FANET); which keeps changing its topology due to its dynamic nature, causing inefficient communication, and therefore needs cluster formation. In this paper, we proposed a cluster formation, selection of cluster head and its members, connectivity and transmission with the base station using the K-means algorithm, and choice of an optimized path for transmission using firefly optimization algorithm for efficient communication. Evaluation of performance with experimental results are obtained and compared using the K-means algorithm and firefly optimization algorithm in cluster building time, cluster lifetime, energy consumption, and probability of delivery success. On comparison of firefly optimization algorithm with firefly optimization algorithm, i.e., K-means algorithm results proved than without firefly optimization algorithm, better in terms of cluster building time, energy consumption, cluster lifetime, and also the probability of delivery success.
Enterprise architecture-based ISA model development for ICT benchmarking in construction-case study
Authors: Adwan Ehab Juma , Al-Soufi Ali
Published: July 2022

Building on a coincided in progress paper, this paper constructs and evaluate an information systems architecture (ISA) model for the Bahraini architecture, engineering and construction (AEC) sector, from the lens of enterprise architecture (EA). This model acts as an information and communication technology (ICT) barometer tool to identify and benchmark the ICT’s gaps, duplicative levels, and future investments. Following the design science research, this paper and throughout a utilization of a tailored version of the open group architectural framework (TOGAF), embedded into a rigorous case study approach, the construction, testing, and evaluation of the conceptual ISA model is approached to benchmark the ICT measurement. Empirically, the study revealed the appropriateness of the model and the ability to identify the availability of 28 groups of 38 individual ICT applications in the Bahraini AEC sector and benchmark them to score an average of 18.5% against 17 countries that scored an average of 18.6%.
Assessment of field oriented induction machine control strategy using new generation of inverters in BB36000 locomotive
Authors: Chaikhy Hamid , Es-saadi Mouna , Khafallah Mohamed
Published: July 2022

Due to their excellent characteristics; Reaching high voltage inverters by using lower voltage switches, reduced output current distortion, dv/dt, and switching losses decrease, efficiency rise, multilevel inverters are an interesting alternative to the two-level inverters especially in traction applications. Many studies compared both topologies, but this work compare performances of Field oriented control strategy using two levels and neutral point piloted three levels inverter supplied by space pulse width modulation. Based on real parameters, this work shows that this efficient multilevel inverter reduces current distortion and torque ripples in a manner to reduces the size and cost of all railway traction systems chosen for this work
Economic evaluation of induction motor based on motor’s nameplate data and initial cost
Authors: Baniyounis Mohammed , Agha Ayamn , Al-kashashneh Hudefah , Al-Omoush Abdullah
Published: July 2022

This paper presents a practical approach to calculate the total owning cost (TOC) of a three-phase Induction Motor, which is based on the motor’s nameplate data and the purchasing price. The economic evaluation is performed considering both the induction motor electrical energy losses and its amortized annual capital cost. The proposed technique consists of three stages, where the total power losses are determined analytically in the first stage. The load loss factor (LSF) is statistically obtained to determine the total energy losses in the second stage. In the third stage, the economic evaluation was conducted. The obtained results show that the proposed approach is a helpful tool for the decision-maker when comparing the received offers from different vendors and finding the answer to the question of which offer has less TOC. Finally, the proposed method is illustrated through a numerical example and software using MATLAB was performed. Results and conclusions have been summarized and discussed.
Development of performance characterization in VSI fed induction motor drives using random PWM
Authors: Raman Mohan Das , Easwaran Chandirasekaran , Srinivasan Vinod Kumar , Chockalingam Bharatiraja
Published: July 2022

Any industrial or power sector application requires a pulse width modulation (PWM) inverter. Industrial drives in particular are highly concerned with industrial standards. To satisfy the voltage source inverter (VSI) drives objects, a variety of PWM approaches are used, including inverter DC input voltage utilizations, suppression of higher and lower order of harmonics, as well as spreading harmonics, acoustic noise reduction, among others PWMs. One of the better approaches for minimizing noise on voltage source threephase inverter fed drives is random pulse width modulation PWM random palse width modulation (RPWM). Despite the fact that these described RPWM approaches are superior in terms of harmonic spreading and mitigation, these methods are unable to achieve the target DC-link utilizations. As a result, the focus of this paper is on combining multicarrier RPWM principles with space vector PWM space vector pulse width modulation (SVPWM) to produce multi-carrier random SVPWM (MCRSVPWM). The suggested PWM generates random unsystematic triangle carrier (5 kHz, 2.5 kHz, 1.25 kHz, 1 kHz) based pulses, whereas the traditional random PWM techniques are uses a fixed frequency triangular carrier to generate random pulse positions. Asynchronous induction motor driving simulation is carried out using MATLAB/Simulink. The proposed MCRSVPWM is put to the test with a 2kW six-switch VSI-fed induction motor drive system.
Minimization of total harmonic distortion in neutral point clamped multilevel inverter using grey wolf optimizer
Authors: Izzaqi Fahmi Ahyar , Windarko Novie Ayub , Qudsi Ony Asrarul
Published: July 2022

The inverter has been attracting researchers for their application in renewable energy. So far, multilevel inverter is considered as low distortion class, which produces multilevel output voltage imitating a pure sine waveform. However, the needs for free distortion of output voltage have been motivating to improve multilevel pulse width modulation PWM generation method. In this paper, the modified PWM technique is proposed to reduce the voltage total harmonics distortion (THD) of multilevel inverter. This modulation technique is then applied to control a single-phase threelevel neutral point clamped multilevel inverter (NPC-MLI). Grey wolf optimizer (GWO) algorithm is utilized to generate optimal amplitude and phase shift of modified reference signal. The GWO algorithm is then compared with other optimization algorithms such as differential evolution (DE), human psychology optimization (HPO), and particle swarm optimization (PSO) to evaluate their performance in harmonic minimization. The performance of the proposed work is validated through simulation and experimentation on a prototype. The results show that the modified PWM technique optimized with GWO can reduce THD on NPC-MLI output voltage.
Thermodynamic analysis of a thermoelectric air conditioner
Authors: Channoy Chanchira , Maneewan Somchai , Punlek Chantana
Published: July 2022

This paper discusses the results of tests done to investigate the performance of a thermoelectric air conditioner (TEAC). The TEAC is composed of twelve thermoelectric modules (TEMs). The TEMs were fixed to rectangular fin heat sinks on both their hot and cold sides. With an increased input voltage, the cooling capacity increased. At a 6 V input voltage flow, a suitable condition occurred. The rate of hot air flow was 0.48 kg/min, and the cooling capacity was 157.0 W, resulting in an outlet air temperature of 28 oC. The coefficient of performance (COP) was calculated and found to be 0.92. Exergy analysis is used to determine the energy flows and second law efficiencies of a TEMs system and its components. The exergy destruction and second law efficiency were observed to increase when the TEAC's input voltage was increased. The TEAC's maximum exergy efficiency was 0.35, which was low compared to the coefficient of performance.
Developing a hybrid filter structure and a control algorithm for hybrid power supply
Authors: Sychev Yuriy Anatolievich , Aladin Maxim Evgenievich , Aleksandrovich Serikov Vladimir
Published: July 2022

The paper presents the results of a study on hybrid filter operation and performance under hybrid power supply. In the study, a hybrid filter structure was developed and proved to perform a set of power quality improving functions. The paper demonstrates that it is necessary for the hybrid filter structure to be variable in order to adapt to changes in power supply. A case is made for using an additional passive filter at the active part output of the hybrid filter under distributed generation. The optimal structure and parameters of such an additional passive filter are identified and proved. Based on the experimental research results, the mathematical and computer simulation models of the proposed hybrid filter for hybrid power supply were developed. The modeling and simulation results showed the efficiency level to be satisfactory and power quality to improve due to applying the proposed hybrid filter. Using the modeling and simulation results, an adaptive algorithm to control the operation factors of the proposed hybrid filter under hybrid power supply was developed, tested, and evaluated. Practical recommendations for industrial application of the proposed hybrid filter are given.
A novel algorithm for optimal sizing of stand-alone photovoltaic pumping systems
Authors: Hafian Asmae , Benbrahim Mohammed , Kabbaj Mohammed Nabil
Published: July 2022

Pumping water is one of the most popular technologies of solar energy for irrigation or drinking water supply. Its performance depends on the characteristics of the site (sunlight, ambient temperature, geographical obstacles), on the performance of the modules, as well as, on the characteristics of other equipment (converter and pump). The optimal sizing of a photovoltaic water pumping system makes it possible to guarantee the satisfaction of the water demand throughout the irrigation period and to model the electrical energy needs to supply the pump to irrigate the crops and water livestock. This paper proposed a novel algorithm for dimensioning the elements of an autonomous photovoltaic system equipped with irrigation water storage. The proposed algorithm determines the optimal surface area of the photovoltaic modules and the electrical power necessary to satisfy the water requirement for irrigation in the observed time. The results obtained from the proposed algorithm for optimal sizing are compared to calculation scenarios to show better results. A case study from the Fez-Meknes region in Morocco has been selected for applying the optimal sizing algorithm.
Laparoscopically Confirmed Endometriosis and Risk of Incident Stroke: A Prospective Cohort Study
Authors: Farland Leslie V. , Degnan William J. , Bell Melanie L. , Kasner Scott E. , Liberman Ava L. , Shah Divya K. , Rexrode Kathryn M. , Missmer Stacey A.
Published: July 2022

Background:

Prior research suggests that women with endometriosis are at greater risk of coronary heart disease. Therefore, our objective was to prospectively investigate the association between laparoscopically confirmed endometriosis and risk of incident stroke during 28 years of follow-up.

Methods:

Participants in the NHSII cohort study (Nurses’ Health Study II) were followed from 1989 when they were between the ages of 25 to 42 until 2017 for development of incident stroke (ischemic and hemorrhagic). Cox proportional hazard models were used to calculate hazard ratios and 95% CI, with adjustment for potential confounding variables (alcohol intake, body mass index at age 18, current body mass index, age at menarche, menstrual cycle pattern in adolescence, current menstrual cycle pattern, parity, oral contraceptive use history, smoking history, diet quality, physical activity, NSAID use, aspirin use, race/ethnicity, and income). We estimated the proportion of the total association mediated by history of hypertension, hypercholesterolemia, hysterectomy/oophorectomy, and hormone therapy. We also tested for effect modification by age (<50,
≥
50 years), infertility history, body mass index (<25,
≥
25 kg/m
2
), and menopausal status.

Results:

We documented 893 incident cases of stroke during 2 770 152 person-years of follow-up. Women with laparoscopically confirmed endometriosis had a 34% greater risk of stroke in multivariable-adjusted models (hazard ratio, 1.34 [95% CI, 1.10–1.62]), compared to those without a history of endometriosis. Of the total association of endometriosis with risk of stroke, the largest proportion was attributed to hysterectomy/oophorectomy (39% mediated [95% CI, 14%–71%]) and hormone therapy (16% mediated [95% CI, 5%–40%]). We observed no differences in the relationship between endometriosis and stroke by age, infertility history, body mass index, or menopausal status.

Conclusions:

We observed that women with endometriosis were at elevated risk of stroke. Women and their health care providers should be aware of endometriosis history, maximize primary cardiovascular prevention, and discuss signs and symptoms of cardiovascular disease.
Pathways to an International Agreement to Leave Fossil Fuels in the Ground
Authors: van Asselt Harro , Newell Peter
Published: July 2022

To achieve the Paris Agreement’s temperature goal, fossil fuel production needs to undergo a managed decline. While some frontrunner countries have already begun to adopt policies and measures restricting fossil fuel supply, an outstanding question is how international cooperation in support of a managed decline of fossil fuel production could take shape. This article explores two possible pathways—one following a club model and the other more akin to a multilateral environmental agreement. Specifically, the article discusses the participants in an international agreement; the forum through which cooperation will take place; the modalities, principles, and procedures underpinning the agreement; and the incentives to induce cooperation. The article concludes that the most likely scenario at this juncture is the emergence of club arrangements covering particular fossil fuel sources and groups of actors that, over time, give rise to growing calls for a more coordinated and multilateral response.
A new species of stream toad of the genus Ansonia Stoliczka, 1870 (Anura: Bufonidae) from Nakhon Si Thammarat Range in southern Thailand
Authors: SUWANNAPOOM CHATMONGKON , GRISMER L. LEE , PAWANGKHANANT PARINYA , POYARKOV NIKOLAY A.
Published: July 2022

An integrative taxonomic analysis confirmed the new species status of a recently discovered upland population of Ansonia from Thongsong, Thongsong District, Nakhon Si Thammarat Province, Thailand from the sky island archipelago south of the Isthmus of Kra. Ansonia infernalis sp. nov. is a member of the Thai-Burmese clade within the more inclusive Thai-Malaya Peninsula clade of western and southern Thailand. It is separated from all other species of Ansonia by a unique combination of morphometric and discrete morphological and color pattern characteristics and is the sister species of a clade of eight other species found north of the Isthmus of Kra. Ansonia infernalis sp. nov. is the newest member of a long list of range-restricted endemics from the sky island archipelago of the Thai-Malay Peninsula and continues to underscore the unexplored nature of this region and its need for conservation.
Revision of the bark louse genus Ceratostigma Li, 2002 (Psocodea: Psocidae: Psocinae) with description of a new species from China
Authors: JIE LULAN , LIANG FEIYANG , LIU XINGYUE
Published: July 2022

The bark louse genus Ceratostigma Li, 2002 is revised with description of Ceratostigma stagona sp. n., from Xizang Autonomous Region, China. A new combination of an Indonesian endemic species, C. lisae (Thornton, 1984) comb. n., is proposed, and thus Ceratostigma is newly recorded from Indonesia. A distribution map and a key to species of Ceratostigma are also provided.
A new species of Bactrocera Macquart and a new distribution record of Dacus Fabricius (Diptera: Tephritidae: Dacinae) from India
Authors: SINGH MANEESH PAL , SHARMA ISHA , HANCOCK DAVID LAWRENCE , PRABHAKAR CHANDRA SHEKHAR
Published: July 2022

A new species of Bactrocera Macquart, Bactrocera (Bactrocera) divenderi Maneesh, Hancock and Prabhakar, sp. n., is described from Himachal Pradesh, Northern India and also recorded from Bhutan and northern Pakistan. It belongs to the B. (B.) nigrotibialis complex and a key to the complex is provided. Dacus (Mellesis) fletcheri Drew is newly recorded from India and records of B. (B.) invadens Drew, Tsuruta & White from the Himalayan region are discussed.
Comparative genomics reveals the molecular mechanism of salt adaptation for zoysiagrasses
Authors: Wang Wei , Shao An , Xu Xiao , Fan Shugao , Fu Jinmin
Published: July 2022

Background

Zoysiagrass (Zoysia spp.) is a warm-season turfgrass. It is widely used as turfgrasses throughout the world, offers good turf qualities, including salt tolerance, resistance to drought and heat. However, the underlying genetic mechanism of zoysiagrass responsive to salt stress remains largely unexplored.

Results

In present study, we performed a whole-genome comparative analysis for ten plant genomes. Evolutionary analysis revealed that Chloridoideae diverged from Panicoideae approximately 33.7 million years ago (Mya), and the phylogenetic relationship among three zoysiagrasses species suggested that Zoysia matrella may represent an interspecific hybrid between Zoysia japonica and Zoysia pacifica. Genomic synteny indicated that Zoysia underwent a genus-specific whole-genome duplication (WGD) event approximately 20.8 Mya. The expression bais of homologous genes between the two subgenomes suggested that the B subgenome of Z. japonica contributes to salt tolerance. In additon, comparative genomic analyses revealed that the salt adaptation of Zoysia is likely attributable to the expanded cytochrome P450 and ABA biosynthetic gene families. Furthermore, we further found that many duplicated genes from the extra WGD event exhibited distinct functional divergence in response to salt stress using transcriptomic analysis, suggesting that this WGD event contributed to strong resistance to salt stress.

Conclusions

Here, our results revealed that expanded cytochrome P450 and ABA biosynthetic gene families, and many of those duplicated genes from recent zoysia-specific WGD event contributed to salt adaptation of zoysiagrass, which provided insight into the genetic underpinning of salt adaptation and valuable information for further studies on salt stress-related traits in Zoysia.
Prognostic value of platelet count-related ratios on admission in patients with pyogenic liver abscess
Authors: Li Shixiao , Yu Sufei , Qin Jiajia , Peng Minfei , Qian Jiao , Zhou Peng
Published: July 2022

Objective

The purpose of the current study was to evaluate the association between C-reactive protein-to-platelet ratio (CPR), neutrophil-to-lymphocyte*platelet ratio (NLPR) and fibrinogen-to-platelet ratio (FPR) and the prognoses of pyogenic liver abscess (PLA) patients.

Methods

A cohort of 372 patients with confirmed PLA were enrolled in this retrospective study between 2015 and 2021. Laboratory data were collected on admission within 24 h. The demographic characteristics and clinical features were recorded. Risk factors for outcomes of PLA patients were determined via multivariate logistic regression analyses, and optimal cut-off values were estimated by using the receiver operating characteristic (ROC) curve analysis.

Results

Out of 372 patients, 57.8% were men, 80 (21.5%) developed sepsis, and 33 (8.9%) developed septic shock. The levels of CPR, NLPR and FPR were significantly increased in the development of sepsis, and prolonged hospital stays in PLA patients. The multivariate logistic regression analysis indicated that the CPR (OR: 2.262, 95% CI: 1.586–3.226, p < 0.001), NLPR (OR: 1.118, 95% CI: 1.070–1.167, p < 0.001) and FPR (OR: 1.197, 95% CI: 1.079–1.329, p = 0.001) were independent risks of PLA patients with sepsis, and NLPR (OR: 1.019, 95% CI: 1.004–1.046, p = 0.019) was shown to be an independent predictor of prolonged hospital stays. The ROC curve results showed that the three biomarkers had different predictive values, and CPR proved to work best, with a ROC value of 0.851 (95% CI: 0.807–0.896, p < 0.001) for sepsis.

Conclusion

Higher levels of CPR, NLPR and FPR were associated with a higher risk of poor outcomes. Moreover, a high CPR level performed best when predicting the clinical outcome in PLA patients.
Comprehensive analysis of the prognosis and immune infiltration landscape of RNA methylation-related subtypes in pancreatic cancer
Authors: Lu Siyuan , Hua Jie , Liu Jiang , Wei Miaoyan , Liang Chen , Meng Qingcai , Zhang Bo , Yu Xianjun , Wang Wei , Xu Jin
Published: July 2022

Background

RNA methylation refers to a form of methyl modification in RNA that modulates various epigenetic alterations. Mounting studies have focused on its potential mechanisms in cancer initiation and progression. However, the prognostic value and potential role of RNA methylation in the immune microenvironment of pancreatic cancer remain unclear.

Methods

Comprehensive bioinformatics analysis was performed to illuminate the expression profiles of RNA methylation modulators. In addition, the ConsensusClusterPlus algorithm was utilized to identify two remarkably different subtypes, and a feasible risk stratification method was established to accurately estimate prognosis. In addition, we validated our signature at the cytology and histology levels and conducted functional experiments to explore the biological functions of our key genes.

Results

Two subtypes with remarkable survival differences were identified by the consensus clustering algorithm. Cluster 2 tended to have higher expression levels of RNA methylation regulators and to be the high RNA methylation group. In addition, cluster 1 exhibited a significantly higher abundance of almost all immune cells and increased immune checkpoint expression compared to cluster 2. Chemotherapeutic sensitivity analysis indicated that there were significant differences in the sensitivity of four of the six drugs between different subgroups. Mutation investigation revealed a higher mutation burden and a higher number of mutations in cluster 2. An accurate and feasible risk stratification method was established based on the expression of key genes of each subtype. Patients with low risk scores exhibited longer survival times in one training (TCGA) and two validation cohorts (ICGC, GSE57495), with p values of 0.001, 0.0081, and 0.0042, respectively. In addition, our signature was further validated in a cohort from Fudan University Shanghai Cancer Center. The low-risk group exhibited higher immune cell abundance and immune checkpoint levels than the high-risk group. The characteristics of the low-risk group were consistent with those of cluster 1: higher stromal score, estimate score, and immune score and lower tumor purity. Additionally, cell function investigations suggested that knockdown of CDKN3 remarkably inhibited the proliferation and migration of pancreatic cancer cells.

Conclusions

RNA methylation has a close correlation with prognosis, immune infiltration and therapy in pancreatic cancer. Our subtypes and risk stratification method can accurately predict prognosis and the efficacy of immune therapy and chemotherapy.