362 research outputs found

    Optimization of the Critical Instrumental parameters in Analysis of some Trace Elements in Sodium chloride Matrix by Flame Spectrometry

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    The optimization of the instrumental parameters of flame atomic absorption including effect of burner height, flame stoichiometry of fuel to oxidant were studied.  The presence of highly interfering matrix such as sodium chloride on the absorption signals of cadmium,  chromium, manganese and nickel were also investigated in order to examine the effect of matrix concentration on the absorption signal and then the reality of the absorbance values given by the instrument, hence the sensitivity and reproducibility of the instrument readings and then sensitivity and reproducibility of the analysis were tested . Improvements of analysis in presence of highly interfering matrices using some releasing agent were also studied

    Modified technique for sacrospinous-sacrotuberous ligament complex colpopexy in apical prolapse: preliminary results of a pilot randomized study

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    Background: Apical prolapse is frequently encountered following vaginal hysterectomy either or as a primary finding in patients with pelvic organ prolapse. This pilot comparative study introduces a modified sacrospinous sacrotuberous ligament fixation with biologic mesh augmentation which necessitates no special kits to be performed.Methods: This study was conducted at Department of Obstetrics and gynecology, Ain Shams University, Cairo, Egypt, and Department of Women Health of Bethanien Hospital, Iserlöhn, Germany from March 2018 to May 2020. 40 women with either utero-vaginal or vaginal vault prolapse were randomized to either; group (A): 20 women scheduled for modified sacrospinous-sacrotuberous fixation procedure, or group (B): 20 women scheduled for conventional sacrospinous-sacrotuberous fixation procedure.Results: Improvement of the Pelvic organ prolapse quantification system (POP-Q) stage from the base line pre-operative stage was 1 stage higher in the modified SS/ST-F group compared to the conventional SSF group (3 stage improvement from baseline in SS/ST-F group versus 2 stage improvement only in conventional SSF group).Conclusions: This pilot study provides a modified sacrospinous sacrotuberous ligament colpopexy technique which is easier to be performed and mastered, does not need the use of special devices, provides better improvement of grade of prolapse and less complications compared to the conventional technique.

    Influence of Melissa officinalis essential oil and its formulation on Typhlodromips swirskii and Neoseiulus barkeri (Acari: Phytoseiidae)

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    The toxicity of Melissa officinalis L. essential oil and its formulation (Melissacide) were evaluated against eggs and females of two predatory phytoseiid mites, Typhlodromips swirskii (Athias Henriot) and Neoseiulus barkeri (Hughes), using direct spray. Results indicate that both tested materials were potent on predatory females than egg stage. Typhlodromips swirskii was proved to be more sensitive to the oil and formulation than N. barkeri. Females mortality were (62-100%) in T. swirskii, and (46-69%) in N. barkeri, when both predatory mites were sprayed with LC50 and LC90 of the oil and Melissacide reported on Tetranychus urticae Koch. Females of both predators were suffered from reduction in food consumption when sprayed with two sublethal concentrations of Melissacide, while insignificant differences reported in daily number of eggs deposited by females of T. swirskii, when sprayed with its LC25 value of Melissacide and control

    Humanizing GenAI at work: bridging the gap between technological innovation and employee engagement

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    Purpose: This paper seeks to explore the influence of generative artificial intelligence (GenAI) on employee performance in the workplace, viewed from a managerial perspective. It concentrates on key elements such as employee engagement, trust in GenAI and attitudes toward its implementation. This exploration is motivated by the ongoing evolution of GenAI, which presents managers with the crucial task of understanding and integrating this technology into their strategic frameworks. Design/methodology/approach: We collected 251 responses from managers and senior managers representing companies that have embraced GenAI in Spain. A hierarchical regression analysis was employed to examine the hypotheses. Subsequently, mediating effects and moderated mediation effects were scrutinized using the bias-corrected bootstrapping method. Findings: The data analysis suggests a significant enhancement in employee engagement and performance from a managerial perspective, attributed to improved attitudes and trust toward the adoption of GenAI. This conclusion is drawn from our research conducted with samples collected in Spain. Notably, our findings indicate that while positive attitudes toward GenAI correlate with enhanced engagement and performance, there exists a weakening effect on the significant positive impact of GenAI adoption in the workplace. This suggests that GenAI is still in its early stages of adoption within these companies, necessitating additional time for managers to develop greater confidence in its efficacy. Originality/value: This study represents one of the pioneering investigations centered on the implementation of GenAI within the workplace context. It contributes significantly to the existing body of literature concerning the stimulus-organism-response (S-O-R) model in technology innovation adoption within work environments

    Investigation of the Influence of Ambient Conditions on the Thermodynamic Characteristics of Air as a Working Fluid for Gas Turbines

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    The study focuses on estimating thermodynamic characteristics at constant pressure for ambient air as a working fluid for gas turbines. The objective of this paper is to carry out a thermodynamic analysis of the properties of air as a working gas for a power plant. Various values of relative humidity, as well as temperatures, were examined in this study. Code was written using EES (Engineering Equations Solver) to conduct the simulation. This code contains the necessary equation to compute the thermodynamic characteristics of the working fluid. According to the results, both temperature and relative humidity remarkably influence the specific heat capacity (C_p), isentropic exponent (γ_h) as well as the gas constant of air (R_h). According to the results, when the ambient air temperature is increased from 0 to 45 ℃ with constant relative humidity values of either 10% or 90%, the specific heat capacity increases by 5.01% and 17.6%, respectively. Furthermore, the isentropic exponent decreases by 1.07% and 4.5%, respectively. The results show that the gas constant of air increases with ambient air temperature and relative humidity. One can conclude that the ambient conditions have considerable influence on the thermodynamic characteristics of a gas turbine working fluid. © 2023, Semarak Ilmu Publishing. All rights reserved.This research was not funded by any grant

    Influence of Surrounding Air Temperature and Humidity upon the Performance of a Gas Turbine Power Plant

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    Nowadays, energy demand continuously rises while energy stocks are dwindling. Using current resources more effectively is crucial for the world. A wide method to effectively utilize energy is to generate electricity using thermal gas turbines (GT). One of the most important problems that gas turbines suffer from is high ambient air temperature especially in summer. The current paper details the effects of ambient conditions on the performance of a gas turbine through energy audits taking into account the influence of ambient conditions on the specific heat capacity (Cp), isentropic exponent (γh) as well as the gas constant of air (Rh). A computer program was developed to examine the operation of a power plant at various ambient temperatures and relative humidities. The ambient temperatures ranged from 0 to 45 ºC, with relative humidities from 10 to 90%. The obtained results show that a GT operated at increased inlet air temperatures is characterized by lower net power and thermal efficiency. At higher inlet air temperatures, increased relative humidity has a slight positive impact on the GT cycle net power and its thermal efficiency. Net output power of the GT decreased from 93.3 MW at 15 °C to 70 MW at 45 °C. Its efficiency decreased from 32.32% at 5 °C to 28.3% at 30 °C. Although fuel consumption is reduced, the heat rate as well and the specific fuel consumption (SFC) are enhanced. SFC increased by 5.36% with a 10 °C temperature rise in temperature at a constant relative humidity. Therefore, use of a gas turbine with inlet air cooling and humidification is appropriate for improved GT efficiency. © 2023, Semarak Ilmu Publishing. All rights reserved.This research was not funded by any grant

    Spoken language identification based on the enhanced self-adjusting extreme learning machine approach

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    Spoken Language Identification (LID) is the process of determining and classifying natural language from a given content and dataset. Typically, data must be processed to extract useful features to perform LID. The extracting features for LID, based on literature, is a mature process where the standard features for LID have already been developed using Mel-Frequency Cepstral Coefficients (MFCC), Shifted Delta Cepstral (SDC), the Gaussian Mixture Model (GMM) and ending with the i-vector based framework. However, the process of learning based on extract features remains to be improved (i.e. optimised) to capture all embedded knowledge on the extracted features. The Extreme Learning Machine (ELM) is an effective learning model used to perform classification and regression analysis and is extremely useful to train a single hidden layer neural network. Nevertheless, the learning process of this model is not entirely effective (i.e. optimised) due to the random selection of weights within the input hidden layer. In this study, the ELM is selected as a learning model for LID based on standard feature extraction. One of the optimisation approaches of ELM, the Self-Adjusting Extreme Learning Machine (SA-ELM) is selected as the benchmark and improved by altering the selection phase of the optimisation process. The selection process is performed incorporating both the Split-Ratio and K-Tournament methods, the improved SA-ELM is named Enhanced Self-Adjusting Extreme Learning Machine (ESA-ELM). The results are generated based on LID with the datasets created from eight different languages. The results of the study showed excellent superiority relating to the performance of the Enhanced Self-Adjusting Extreme Learning Machine LID (ESA-ELM LID) compared with the SA-ELM LID, with ESA-ELM LID achieving an accuracy of 96.25%, as compared to the accuracy of SA-ELM LID of only 95.00%

    Regional variance in treatment and outcomes of locally invasive (T4) rectal cancer in Australia and New Zealand: analysis of the Bi-National Colorectal Cancer Audit

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    BACKGROUNDS: Locally invasive T4 rectal cancer often requires neoadjuvant treatment followed by multi-visceral surgery to achieve a radical resection (R0), and referral to a specialized exenteration quaternary centre is typically recommended. The aim of this study was to explore regional variance in treatment and outcomes of patients with locally advanced rectal cancer in Australia and New Zealand (ANZ). METHODS: Data were collected from the Bi-National Colorectal Cancer Audit (BCCA) database. Rectal cancer patients treated between 2007 and 2019 were divided into six groups based on region (state/country) using patient postcode. A subset analysis of patients with T4 cancer was performed. Primary outcomes were positive circumferential resection margin (CRM+), and positive circumferential and/or distal resection margin (CRM/DRM+). RESULTS: A total of 9385 patients with rectal cancer were identified, with an overall CRM+ rate of 6.4% and CRM/DRM+ rate of 8.6%. There were 1350 patients with T4 rectal cancer (14.4%). For these patients, CRM+ rate was 18.5%, and CRM/DRM+ rate was 24.1%. Significant regional variation in CRM+ (range 13.4-26.0%; p = 0.025) and CRM/DRM+ rates (range 16.1-29.3%; p = 0.005) was identified. In addition, regions with higher CRM+ and CRM/DRM+ rates reported lower rates of multi-visceral resections: range 24.3-26.8%, versus 32.6-37.3% for regions with lower CRM+ and CRM/DRM+ rates (p < 0.0001). CONCLUSION: Positive resection margins and rates of multi-visceral resection vary between the different regions of ANZ. A small subset of patients with T4 rectal cancer are particularly at risk, further supporting the concept of referral to specialized exenteration centres for potentially curative multi-visceral resection.Tessa L. Dinger, Hidde M. Kroon, Luke Traeger, Sergei Bedrikovetski, Andrew Hunter and Tarik Sammou

    Design of a multi-level inverter for solar power systems with a variable number of levels technique

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    Overall harmonic distortion and losses will grow during an energy conversion process, while power stability will be reduced. Multilevel inverter technologies have recently become very popular as low-cost alternatives for a variety of industrial purposes. The design's minimal benefits include reduced component losses, decreased switching and conduction losses, along with enhanced output voltage and current waveforms. Also, a reduction of the harmonic components of the current and output voltage of the inverter are the most important requirements in multilevel inverters. A seven-level inverter design is presented in this paper that is simulated using MATLAB/Simulink. The inverter converts the DC voltage from three photovoltaic (PV) systems into AC voltage at seven levels. During an outage of one of the PV systems, the inverter will make a switching reduction and supply the AC voltage as a five-level inverter. The inverter’s total harmonic distortion (THD) when it performs as a five-level or seven-level inverter is 4.19% or 1.13% respectively. The modulation technique used is phase disposition via six carriers and a single reference signal at the fundamental frequency. © 2023, Institute of Advanced Engineering and Science. All rights reserved.Ministry of Education and Science of the Russian Federation, Minobrnauka: FEUZ-2022-0031Funding from the Ministry of Science and Higher Education of the Russian Federation (Ural Federal University Program of Development within the Priority-2030 Program) is gratefully acknowledged: Grant Number FEUZ-2022-0031
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