Use Of Performance Research Articles

Electrochemical Performance of Niobium MXenes with Lanthanum.

MXenes are the newest class of two-dimensional nanomaterials characterized by large surface area, high conductivity, and hydrophilicity. To further improve their performance for use in energy storage devices, heteroatoms or functional groups can be inserted into the Mxenes' structure increasing their stability. This work proposes insertion of lanthanum atoms into niobium-MXene (Nb-MX/La) that was characterized in terms of morphogy, structure, and electrochemical behavior. The addition of La to the Nb-MXene structure was essential to increase the spacing between the layers, improving the interaction with the electrolyte and enabling charge/discharge cycling in a higher potential window and at higher current densities. Nb-MX/La achieved a specific capacitance of up to 157 mF cm-2, a specific capacity of 42 mAh cm-2 at 250 mV s-1, a specific power of 37.5 mW cm-2, and a specific energy of 14.1 mWh cm-2 after 1000 charge/discharge cycles at 50 mA cm-2.

Analytical verification of the Atellica VTLi point of care high sensitivity troponin I assay.

The Siemens Point-of-Care Testing (POC) Atellica® VTLi high-sensitivity troponin I (hsTnI) device has been previously validated. Verification independently provides evidence that an analytical procedure fulfils concordance with laboratory assays, imprecision, and hemolysis interference requirements. Five whole blood samples spanning the measuring interval were analysed 20 times in succession. Hemolysis interference was assessed at three troponin concentrations by spiking five hemolysate concentrations to plasma to achieve free hemoglobin concentrations 35-1,000 mg/dL. Concordance between whole blood (VTLi) and plasma on laboratory analysers (Beckman, Roche, Siemens) was assessed by Pearson correlation and kappa statistics at the (LOQ) and upper reference limit (URL). This was repeated for frozen plasma samples. Coefficients of variation for whole blood were <10 % for whole blood troponin concentrations of 9.2 and 15.9 ng/L, thus below the URL. Hemolysis positively interfered; at 250 mg/dL affecting the low troponin sample (+3 ng/L; +60 %) and high troponin sample (+37 ng/L; +24 %). Correlation coefficients were 0.98, 0.90 and 0.97 between VTLi and Beckman, Roche and Siemens assays respectively. Corresponding kappa statistics were 0.80, 0.73 and 0.84 at the LOQ and 0.70, 0.44 and 0.67 at the URL. Concordances between VTLi and laboratory assays were at least non-inferior to those between laboratory assays. Imprecision met manufacturer claims and was consistent with a high sensitivity assay. There is potential for hemolysis interference, highlighting the need for quality samples. The results support performance characteristics previously reported in validation studies, and the device offers acceptable performance for use within intended medical settings.

Investigation on mechanical and tribological properties of PTFE nanocomposites reinforced by surface-modified graphene using molecular dynamics simulations

Surface-modified nanoparticles are commonly used to improve the mechanical properties and wear resistance of polytetrafluoroethylene (PTFE). However, fewer studies have been devoted to quantitatively revealing the action mechanism of graphene (Gr) modified with different functional groups on the mechanical and tribological properties of PTFE. Herein, the effects of four functional groups (−OH, −NH2, −COOH, and −COOCH3 functional groups) on the surface of Gr nanosheets on the mechanical and tribological properties of PTFE nanocomposites are studied using molecular dynamics simulations. The results indicate that the incorporation of functional groups to the Gr surface is able to significantly improve the mechanical properties and wear resistance of the nanocomposites, and the COOH-functionalized Gr nanosheet shows the best reinforcing effect due to the synergistic effect of its own high surface roughness and strong interfacial interaction between itself and the matrix. It is also found that the friction coefficient of the nanocomposites is obviously increased by the inclusion of functionalized Gr nanosheets, and the greater the surface roughness of the functionalized Gr nanosheet, the more significant the growth of the friction coefficient of the nanocomposites. The pull-out test and confined shear simulation reveal that due to the increased interfacial shear strength and the isolation of functional groups, an inhomogeneous transfer film is formed at the friction interface, leading to a decreased anti-friction property. This study provides some guidance for the future design and development of polymer nanocomposites with excellent mechanical and tribological performance for use in extreme service conditions.

Emulsion-Templated Gelatin/Amino Acids/Chitosan Macroporous Hydrogels with Adjustable Internal Dimensions for Three-Dimensional Stem Cell Culture.

The demand for macroporous hydrogel scaffolds with interconnected porous and open-pore structures is crucial for advancing research and development in cell culture and tissue regeneration. Existing techniques for creating 3D porous materials and controlling their porosity are currently constrained. This study introduces a novel approach for producing highly interconnected aspartic acid-gelatin macroporous hydrogels (MHs) with precisely defined open pore structures using a one-step emulsification polymerization method with surface-modified silica nanoparticles as Pickering stabilizers. Macroporous hydrogels offer adjustable pore size and pore throat size within the ranges of 50 to 130 μm and 15 to 27 μm, respectively, achieved through variations in oil-in-water ratio and solid content. The pore wall thickness of the macroporous hydrogel can be as thin as 3.37 μm and as thick as 6.7 μm. In addition, the storage modulus of the macroporous hydrogels can be as high as 7250 Pa, and it maintains an intact rate of more than 92% after being soaked in PBS for 60 days, which is also good performance for use as a biomedical scaffold material. These hydrogels supported the proliferation of human dental pulp stem cells (hDPSCs) over a 30 day incubation period, stretching the cell morphology and demonstrating excellent biocompatibility and cell adhesion. The combination of these desirable attributes makes them highly promising for applications in stem cell culture and tissue regeneration, underscoring their potential significance in advancing these fields.

Investigation of Influence of Variations of Ageing Conditions on Aluminium-Silicon: Pathway to Tailored Mechanical Properties

This study focuses on the investigation of the influence of the variations of ageing conditions on the mechanical properties of ferrosilicon-silicon carbide reinforced Aluminium metal matrix composites. The ageing temperature, reinforcement percentage volume fractions and ageing time of the composite were systematically varied during fabrication stages by keeping the Aluminium and Ferrosilicon compositions constant while varying the percentage volume fractions of Silicon Carbide (SiC). The samples produced were machined into hardness, impact and tensile tests specimens. Then the specimens were subjected to laboratory based accelerated solution heat treatment, quenching and artificial ageing. Array of comprehensive mechanical properties examination and characterization in line with the appropriate specifications of the American Society for Testing and Materials Standard manuals were conducted to determine the influence of ageing on the material’s strength, hardness, impact toughness and stress-strain characteristics. The study revealed significant enhancement in the mechanical properties of the material and the findings would provide valuable insight into the ageing behaviour of Aluminium-Silicon, thus, enabling the optimization of the material’s performance for use in diverse engineering applications.

Effect of polypyrrole-derived N-doped carbon coating on the sodium storage properties of NiCo2S4 synthesized by recycling discarded mobile phone batteries

NiCo2S4 with a spherical spinel structure was innovatively synthesized from discarded mobile phone batteries using a simple hydrothermal method, and the surface was coated with N-doped carbon to form NiCo2S4@NC. The products were used as anode materials of sodium-ion batteries to study the effect of the N-doped carbon layer on the electrochemical properties, structure and morphology. The results of XRD, FESEM and TEM revealed that the N-doped carbon layer derived by carbonizing polypyrrole had a minimal effect on the structure and morphology of NiCo2S4, but was coated on the surface of NiCo2S4 with different thicknesses to adjust the electrochemical performance. The presence of N-doped carbon in NiCo2S4@NC was confirmed by Raman spectroscopy. The mesoporous structure of NiCo2S4 and NiCo2S4@NC was corroborated by N2 adsorption-desorption isotherm analysis, and the optimal specific surface area and pore size were 23.14 cm2/g and 18.0 nm, respectively. X-ray photoelectron spectroscopy indicated that Co2+/Co3+ and Ni2+/Ni3+ coexist in the spinel NiCo2S4@NC50 synthesized upon adding 50 μL of pyrrole monomer. NiCo2S4@NC50 outperformed other products in terms of its electrochemical properties, where its initial discharge specific capacity under the current density of 0.1 A g−1 was 1099.6 mA h g−1 and the specific capacity following 100 cycles reached 327.5 mA h g−1. NiCo2S4@NC50 exhibited an optimal electrochemical performance and demonstrated a competent approach toward recycling discarded mobile phone batteries and building electrodes with high performance for use in energy equipment.

Internal validation of Automated Visual Evaluation (AVE) on smartphone images for cervical cancer screening in a prospective study in Zambia.

Visual inspection with acetic acid (VIA) is a low-cost approach for cervical cancer screening used in most low- and middle-income countries (LMICs) but, similar to other visual tests, is subjective and requires sustained training and quality assurance. We developed, trained, and validated an artificial-intelligence-based "Automated Visual Evaluation" (AVE) tool that can be adapted to run on smartphones to assess smartphone-captured images of the cervix and identify precancerous lesions, helping augment VIA performance. Prospective study. Eight public health facilities in Zambia. A total of 8204 women aged 25-55. Cervical images captured on commonly used low-cost smartphone models were matched with key clinical information including human immunodeficiency virus (HIV) and human papillomavirus (HPV) status, plus histopathology analysis (where applicable), to develop and train an AVE algorithm and evaluate its performance for use as a primary screen and triage test for women who are HPV positive. Area under the receiver operating curve (AUC); sensitivity; specificity. As a general population screening tool for cervical precancerous lesions, AVE identified cases of cervical precancerous and cancerous (CIN2+) lesions with high performance (AUC = 0.91, 95% confidence interval [CI] = 0.89-0.93), which translates to a sensitivity of 85% (95% CI = 81%-90%) and specificity of 86% (95% CI = 84%-88%) based on maximizing the Youden's index. This represents a considerable improvement over naked eye VIA, which as per a meta-analysis by the World Health Organization (WHO) has a sensitivity of 66% and specificity of 87%. For women living with HIV, the AUC of AVE was 0.91 (95% CI = 0.88-0.93), and among those testing positive for high-risk HPV types, the AUC was 0.87 (95% CI = 0.83-0.91). These results demonstrate the feasibility of utilizing AVE on images captured using a commonly available smartphone by nurses in a screening program, and support our ongoing efforts for moving to more broadly evaluate AVE for its clinical sensitivity, specificity, feasibility, and acceptability across a wider range of settings. Limitations of this study include potential inflation of performance estimates due to verification bias (as biopsies were only obtained from participants with visible aceto-white cervical lesions) and due to this being an internal validation (the test data, while independent from that used to develop the algorithm was drawn from the same study).

Polarization‐Graded High‐Electron‐Mobility Transistors for Improved Johnson's Figure of Merit

Polarization grading in AlGaN/GaN‐based high‐electron‐mobility transistors (HEMTs) is a promising device design option that can improve linearity, speed, power, and noise performance for use in millimeter‐wave applications. This work investigates the potential of compositionally graded HEMT heterostructures to enhance device breakdown through lateral electric field engineering while maintaining a high device cutoff frequency (fT) due to reduced longitudinal optical (LO) phonon scattering. The impact of polarization grading on electric field profile is compared with conventional gate‐integrated mini‐field plates (mini‐FPs). It is also observed that polarization grading can augment the efficacy of gate‐connected FPs, further enhancing performance. Using physics‐based 2D device simulations, it is demonstrated that polarization engineering via polarization grading enhances breakdown (VBD) while preserving high fT, resulting in a Johnson's figure of merit (JFOM = fT × VBD), that is, ≈2.4× that of a conventional abrupt‐junction HEMT. This improvement represents a significant advancement over the ≈1.25× to ≈2× increase achieved with the use of mini‐FPs alone in HEMTs.

The affect of rusunawa design changes to resident’s physical quality satisfaction

The physical quality satisfaction has an essential contribution to shaping residents’ sense of place, which affects the sustainability of a setting. Physical quality assessment can help measure the extent to which occupants are satisfied with the physical quality of their housing environment and enable the community to identify and organize their settings. This also includes the legibility and accessibility aspects that allow people to create clear, accurate images and help users adapt to their environment, especially housing and settlement. This study examines the effect of design changes on residents’ physical quality satisfaction levels that occur in Rusunawa Sombo. Rusunawa Sombo is a rental flat complex with 10 blocks that was built in stages from 1989 to 1994. This flat underwent renovations to 2 building blocks (blocks E and K) which were completed in 2021. However, the design of the renovated building is very different from the original building, with a reduction in the corridor’s area, which was previously the center of residents’ communal and domestic activities. This study tries to examine the response of residents’ to these changes. The method used in this study is a mixed method, where quantitative research is the dominant method. This study tried to collect a questionnaire assessment of the physical quality satisfaction for 48 respondents, of which 24 respondents lived in the old Rusunawa Sombo building design (Block A and B), and 24 respondents from the newly renovated building (blocks E and K). The results of the questionnaire were analyzed descriptively through the results of the mean value. The quantitative results were then analyzed using a qualitative descriptive method from observations and interviews with respondents to validate the results. This research is expected to be useful as a post-occupancy evaluation that obtains feedback on a Rusunawa Sombo building’s performance in use after it has been built and occupied.

Artificial Intelligence Approach in Aerospace for Error Mitigation

Many of the reports created at assembly lines, where all components of an aircraft are installed, frequently indicate that errors threaten safety. The proposed methodology in this study evaluates error prediction and risk mitigation to prevent failures and their consequences. The results linked to a typical electrical harness manufacture of a military aircraft estimated reductions of 93% in time and 90% in error during the creation of engineering manufacturing processes using AI techniques. However, traditional risk assessments methods struggle to identify and mitigate errors effectively. Thus, developing an advanced methodology to ensure systems safety is needed. This paper addresses how innovative AI technology solutions can overcome these challenges, mitigate error risks, and enhance safety in aerospace. Technologies, such as artificial intelligence, predictive algorithms, machine learning, and automation, can play a key role in enhancing safety. The aim of this study is to develop a model that considers the factors that can potentially contribute to error creation, through an artificial intelligence (AI) approach. The specific AI techniques used such as support vector machine, random forest, logistic regression, K-nearest neighbor, and XGBoost (Python 3.8.5) show good performance for use in error mitigation. We have compared the modeled values obtained in this study with the experimental ones. The results confirm that the best metrics are obtained by using support vector machine and logistic regression. The smallest deviation between the measured and modeled values for these AI methods do not exceed 5%. Furthermore, using advancements in machine learning methods can enhance error mitigation in aerospace. The use of AutoML can play a key role in automatically finding an appropriate model which provides the best performance metrics and therefore the most reliable forecast for data prediction and error mitigation.

Impact of high-performance human papillomavirus testing to improve cervical cancer screening in China: a prospective population-based multicentre cohort study

ObjectivesThe aim of the study was to evaluate the clinical performance of HBRT-H14, a real-time PCR-based assay that separates human papillomavirus (HPV) 16 and HPV18 from 12 other high-risk (HR) HPV types, in population according to Chinese guideline. MethodsA total of 9829 eligible women aged 21–64 years from Henan, Shanxi, and Guangdong provinces were performed by HBRT-H14 testing and liquid-based cytology (LBC) screening at baseline and followed up for 3-year. The sensitivity, specificity, positive predictive value (absolute risk), and negative predictive value of LBC diagnosis and HPV testing were calculated for cervical intraepithelial neoplasia grade 2 or worse (CIN2+) Lesions. ResultsAt baseline, 80 (0.81%) participants were diagnosed with CIN2+. HR-HPV with reflex LBC had a significantly higher sensitivity (78/80, 97.50% [95% CI, 91.34–99.31%] vs. 62/80, 77.50% [67.21–85.27%], McNemar's test p < 0.001), and a slightly lower specificity (8528/9749, 87.48% [86.80–88.12%] vs. 8900/9749, 91.29% [90.72–91.83%], McNemar's test p < 0.001) than LBC with reflex HR-HPV for CIN2+. 7832 (79.6%) participants completed 3-year follow-up and 172 (2.20%) participants were cumulatively diagnosed with CIN2+. Compared with LBC with reflex HR-HPV, HR-HPV with reflex LBC significantly increased the sensitivity (161/172, 93.60% [88.91–96.39%] vs. 87/172, 50.58% [43.18–57.96%], McNemar's test p < 0.001), but marginally decreased the specificity (6776/7660, 88.46% [87.72–89.16%] vs. 6933/7660, 90.51% [89.83–91.15], McNemar's test p < 0.001). In addition, the absolute 3-year risk of CIN2+ in HPV16/18-positive individuals was as high as 33% (80/238), whereas the risk in the HPV-negative population was only 0.16% (11/6787), much lower than those in the negative for intraepithelial lesion or malignancy population (1.21%, 85/7018). Moreover, similar results were found in women ≥30 years old. DiscussionThe study has indicated that HBRT-14 has a reliable clinical performance for use in cervical screening. The validated HPV test would improve the quality of population screening.

Performance of EOM-CCSD(T)(a)*-Based Quartic Force Fields in Computing Fundamental, Anharmonic Vibrational Frequencies of Molecular Electronically Excited States with Application to the Ã1A″ State of :CCH2 (Vinylidene).

Highly accurate anharmonic vibrational frequencies of electronically excited states are not as easily computed as their ground electronic state counterparts, but recently developed approximate triple excited state methods may be changing that. One emerging excited state method is equation of motion coupled cluster theory at the singles and doubles level with perturbative triples computed via the (a)* formalism, EOMEE-CCSD(T)(a)*. One of the most employed means for the ready computation of vibrational anharmonic frequencies for ground electronic states is second-order vibrational perturbation theory (VPT2), a theory based on quartic force fields (QFFs),fourth-order Taylor series expansions of the potential portion of the internuclear Watson Hamiltonian. The combination of these two is herein benchmarked for its performance for use as a means of computing rovibrational spectra of electronically excited states. Specifically, the EOMEE-CCSD(T)(a)* approach employing a complete basis set extrapolation along with core electron inclusion and relativity (the so-called "CcCR" approach) defining the QFF produces anharmonic fundamental vibrational frequencies within 2.83%, on the average, of reported gas-phase experimentally assigned values for the test set including the states of HCF, HCCl, HSiF, HNO, and HPO. However, some states have exceptional accuracy in the fundamentals, most notably for ν2 of HCCl in which the CcCR QFF value is within 1.8 cm-1 at 927.9 cm-1 (or 0.2%) of the experiment. Additionally, this approach produces rotational constants to, on the absolute average, within 0.41% of available experimental data, showcasing notable accuracy in the computation of rovibronic spectral data. Furthermore, utilizing a hybrid approach composed of harmonic CcCR force constants along with a set of simple EOMEE-CCSD(T)(a)*/aug-cc-pVQZ QFF cubic and quartic force constants is faster than using pure CcCR and better represents those modes that suffer from numerical instability in the anharmonic portion of the QFF, implying that this so-called "CcCR + QZ" QFF approach may be the best for future applications. Finally, complete, rovibrational spectral data are provided for :CCH2, a molecule of potential astrochemical interest, in order to aid in its potential future experimental rovibronic characterization.

Preliminary membrane screening and evaluation for the separation of bioethanol obtained from fermentation of oil palm empty fruit bunch (OPEFB)

This study evaluates the effectiveness of some commercial membranes (polytetrafluoroethylene [PTFE], polyvinylidene fluoride [PVDF], polyethersulfone [PES], and nitrocellulose [NC]) in concentrating a binary ethanol-water mixture under different conditions (volumes, temperatures, pressures, and concentrations). Then, the membrane was selected based on its performance for use in ethanol and by-product separation from OPEFB fermentation broth. The optimum result for the binary ethanol-water separation was found in the PVDF membrane with the highest separation factor of 3.03 and flux of 0.015 g.cm−2 s−1 under 10 ml permeate volume, 75 °C temperature, 60 psi pressure, and 20 % (v/v) ethanol concentration. Based on the membrane field emission-scanning electron microscope (FE-SEM) analysis, the PVDF membrane also had the lowest swelling degree. Utilization of the PVDF membrane to separate crude bioethanol resulting from OPEFB fermentation gave a separation factor of 3.66. The initial bioethanol concentration was 7.67 % (v/v), and the ethanol concentration in the permeate was 23.31 % (v/v). In addition, the separation factor of propanol from the crude mixture was 5.44, and the acetic acid rejection factor was 96.7 %. The S.cerevisiae suspension and the cellulase enzyme were also separated and recovered in the retentate phase. Hence, the PVDF membrane can be used to separate bioethanol from the yeast and enzyme suspension while pre-concentrating the bioethanol product. This could eventually help reduce the energy requirement to obtain industrial-grade bioethanol.

Physical simulation and computational modelling for validation of soft magnetic composite impeder performance

Induction tube welding systems utilize an internal magnetic flux controller (impeder) to improve process efficiency. Work has previously been done showing that soft magnetic composite (SMC) materials may be suitable to improve these systems. A test stand was devised for the physical simulation of SMC impeder performance for use in induction tube welding systems. Tests were run to determine the loading and cooling conditions in which an impeder core made of SMCs could survive. Additionally, 2D thermal simulations were run to determine the cooling system thresholds given a particular magnetic loading of the core. The goal of these tests was to expand the design envelopes in which impeder cores made of SMCs could survive and validate their use in induction tube welding systems.

ASYMMETRIC FLEXURAL BEHAVIOR OF GLULAM BEAMS BASED ON BAMBOO-INSPIRED FUNCTIONALLY GRADED STRUCTURE FOR HIGH BENDING LOAD APPLICATIONS

ABSTRACT Natural materials are being further processed into functionally engineered products to reduce their natural variability and enhance their performance for use in construction, given their noteworthy recyclability, availability and sustainability traits. To date, the mechanical strengths of natural and engineered wood products are limited by their inherent micromechanical characteristics which are outclassed by homogeneous materials like steel and concrete. This study proposes a less process-intensive technique to improve the strength of engineered wood products by considering glulam based on a bio-inspired functionally graded structure. The finite element method was considered to investigate the effects of the functionally graded arrangement on the asymmetric flexural deformation and on the underlying fracture mechanisms in glulam beams. The numerical results showed that the functionally graded arrangements across the cross-section led to an improvement in the bending strength and consequently enhanced the resistance to transverse crack propagation. In the functionally graded glulam beam, the stiffer layers at the bottom were found to promote the onset for longitudinal crack initiation. Moreover, transverse cracks tended to propagate sideways in an orthogonal direction in the beam layers with a high longitudinal to transverse stiffness ratio whereby the tangential normal stress was a maximum. The improvement in performance, which resulted from a shift of the neutral axis and redistribution of stress within the glulam beams, was attributed to the degree of graded arrangement across their cross-section besides the orthotropic characteristics of their individual layers. Key findings of this study could be useful to further develop high-strength engineered wood products based on bio-inspired solutions to replace conventional materials in the construction industry for improved sustainability.

Probiotic performance of B. subtilis MS. 45 improves aquaculture of rainbow trout Oncorhynchus mykiss during acute hypoxia stress

The aim of this study was to produce mutant strains of Bacillus subtilis with high probiotic performance for use in the aquaculture of rainbow trout Oncorhynchus mykiss. The main strain of B. subtilis (MS) was irradiated with gamma rays (5.3 KGy). Subsequently, the B. subtilis mutant strain no. 45 (MS. 45) was selected for bacterial growth performance, resistance to acidic conditions, resistance to bile salts and antibacterial activity against Aeromonas hydrophila and Pseudomonas fluorescens. After 60 days, the rainbow trout (70.25 ± 3.89 g) fed with MS. 45 and MS were exposed to hypoxia stress (dissolved oxygen = 2 ppm). Subsequently, immune indices (lysozyme, bacterial activity and complement activity), hematological indices [hematocrit, hemoglobin, WBC, RBC, mean corpuscular volume (MCV)] and antioxidant factors (T-AOC, SOD and MDA)) were analyzed after and before hypoxia exposure. The expression of immunological genes (IFN-γ, TNF-α, IL-1β, IL-8) in the intestine and the expression of hypoxia-related genes (HIF-1α, HIF-2α, FIH1) in the liver were compared between the different groups under hypoxia and normoxia conditions. Growth, immunological and antioxidant indices improved in group MS. 45 compared to the other groups. Stress indices and associated immunologic and hypoxia expressions under hypoxia and normoxia conditions improved in MS. 45 compared to the other groups. This resulted in improved growth, immunity and stress responses in fish fed with the microbial supplement of MS. 45 (P < 0.05) under hypoxia and normoxia conditions, (P < 0.05), resulting in a significant improvement in trout aquaculture.

Feasibility and Validity of In-Home Self-Collected Capillary Blood Spot Screening for Type 1 Diabetes Risk.

Aims: Self-collection of a blood sample for autoantibody testing has potential to facilitate screening for type 1 diabetes risk. We sought to determine the feasibility and acceptability of this approach and the performance of downstream antibody assays. Methods: People living with type 1 diabetes and their family members (N = 97) provided paired capillary blood spot and serum samples collected, respectively, by themselves and a health worker. They provided feedback on the ease, convenience, and painfulness of blood spot collection. Islet antibodies were measured in blood spots by antibody detection by agglutination PCR (ADAP) or multiplex enzyme-linked immunoassay (ELISA), and in serum by radioimmunoassay (RIA) or ELISA. Results: Using serum RIA and ELISA to define antibody status, 50 antibody-negative (Abneg) and 47 antibody-positive (Abpos) participants enrolled, of whom 43 and 47, respectively, returned testable blood spot samples. The majority indicated that self-collection was easier, more convenient, and less painful than formal venesection. The sensitivity and specificity for detection of Abpos by blood spot were, respectively, 85% and 98% for ADAP and 87% and 100% for multiplex ELISA. The specificities by ADAP for each of the four antigen specificities ranged from 98% to 100% and areas under the receiver operator curve from 0.841 to 0.986. Conclusions: Self-collected blood spot sampling is preferred over venesection by research participants. ADAP and multiplex ELISA are highly specific assays for islet antibodies in blood spots with acceptable performance for use alone or in combination to facilitate screening for type 1 diabetes risk. Clinical Trial Registration number: ACTRN12620000510943.

Real-Time Implementation for the Robust Controller of the Switched Boost Inverter within an Autonomous Modified Nanogrid

SBI stands for switched-boost inverter and is a single-stage power converter used to connect low-power sources, such as solar photovoltaic (PV) arrays within a modified nanogrid, to loads. Despite its many benefits, such as the fact that it does not require expensive sophisticated dead-time circuitry, its duty ratio is limited to between 0 and 0.5. As a result, this publication is a contribution towards improving the SBI's performance for use in a modified nanogrid. Furthermore, it also presents a revolutionary strategy for a simple closed-loop control technique that overcomes the majority of inverter shortcomings and system nonlinearity. The suggested robust controller uses a metaheuristic optimization technique, called gorilla troops optimization (GTO), to optimize the performance of this controller. The robustness of the suggested controller is tested against the sudden change of the nanogrid input voltage (i.e., PV-voltage), modulation index of the inverter, and the step-change in DC-link output voltage of the inverter. The test results obtained from Matlab/Simulink software are compared with particle swarm optimization (PSO) – as another optimization algorithm. Furthermore, the proposed system is experimentally implemented with OPAL RT-4510v real-time hardware in the loop (HIL), rapid control prototyping, OP-8660 HIL controller and data acquisition platform.

Effects of Computer-aided Instruction on Students’ Performance in Use of English in Tertiary Institutions in Anambra State, Nigeria

The research departs from the realization that technological advancement, especially Information and Communication Technology (ICT) is greatly changing the process of teaching and learning, in higher institutions. While this process of change may not yet be so speedy in Nigeria, there is no doubt that the traditional or conventional teaching process is gradually giving way, and the ICT based teaching is setting into the fora of higher education. Using the quasi-experimental design involving pretest, posttest and non-randomized control and experimental groups, the study examined the achievement scores of students taught Use of English using computer-assisted instruction (CAI) and conventional method of teaching. The population of the study comprised all the year one students offering the Use of English. The sample of the study consisted of one thousand and eighteen students drawn from two Universities in Anambra State. Two research questions guided the study and three null hypotheses were tested at 0.05 level significance. The instrument for data collection was Use of English Achievement Test (UEAT) made up of 30 multiple choice test items with four options (A-D) from GSS 101 curriculum. The instrument was validated by three experts and a reliability coefficient of 0.80 was obtained using Kuder-Richardson Formula 20. Data collected were analyzed using mean scores to answer the research questions and Analysis of Covariance (ANCOVA) to test the null hypotheses. Findings revealed a significant difference in the post test scores of students in the control group and experimental group. Although, students in the experimental group (taught Use of English using CAI) had higher mean scores than their counterparts taught using the conventional method of teaching. Also there was no significant difference in the mean scores of male and female students taught Use of English using CAI. Based on the findings it was recommended that Computer-Assistant Instruction should be encouraged in the teaching and learning of Use of English.

Public opinion and persuasion of algorithmic fairness: assessment of communication protocol performance for use in simulation-based reinforcement learning training

Public opinion and persuasion of algorithmic fairness: assessment of communication protocol performance for use in simulation-based reinforcement learning training