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1.
Public Health ; 228: 43-50, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38266347

RESUMO

OBJECTIVES: The current study aimed to describe and estimate the independent effects of age, period, and cohort on colorectal cancer (CRC) mortality in Saudi Arabia from 1990 to 2019. STUDY DESIGN: This was an epidemiological study. METHODS: Data were obtained from the Global Burden of Disease study 2019. Age-period-cohort modelling was used to compute the net drift, local drift, cross-sectional age curve, longitudinal age curve, and rate ratios (RRs) of period and cohort of CRC mortality in Saudi Arabia. RESULTS: In 2019, there were 1629 (95% uncertainty interval [UI]: 1263 to 2045) CRC cancer deaths in Saudi Arabia, and the age-standardised mortality rate of CRC was 9.7 (95% UI: 7.8 to 11.6) per 100,000 population. For men, between 1990 and 2019, the total number of CRC deaths increased dramatically from 199 (95% UI: 130 to 286) in 2019 to 942 (95% UI: 725 to 1228). For the period effects, the relative risk (RR) of mortality rate for both sexes followed similar monotonic increase patterns throughout the study period. CONCLUSIONS: Results from this study highlight a concerning increase in CRC mortality rates in Saudi Arabia from 1990 to 2019, particularly among individuals aged 30-50 years. While mortality rates for men were higher at the start of the study period, more favourable trends for men were seen in the later years of the study period, indicating evolving gender disparities. Establishing evidence-based national screening guidelines and adopting multi-level diagnostics, risk assessment, and population-wide screening, especially for younger populations, is crucial.


Assuntos
Neoplasias Colorretais , Masculino , Feminino , Humanos , Arábia Saudita/epidemiologia , Estudos Transversais , Medição de Risco , Neoplasias Colorretais/epidemiologia , Estudos de Coortes
2.
Sensors (Basel) ; 23(12)2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37420526

RESUMO

In this study, a novel reconfigurable triple-band monopole antenna for LoRa IoT applications is fabricated on an FR-4 substrate. The proposed antenna is designed to function at three distinct LoRa frequency bands: 433 MHz, 868 MHz, and 915 MHz covering the LoRa bands in Europe, America, and Asia. The antenna is reconfigurable by using a PIN diode switching mechanism, which allows for the selection of the desired operating frequency band based on the state of the diodes. The antenna is designed using CST MWS® software 2019 and optimized for maximum gain, good radiation pattern and efficiency. The antenna with a total dimension of 80 mm × 50 mm × 0.6 mm (0.12λ0×0.07λ0 × 0.001λ0 at 433 MHz) has a gain of 2 dBi, 1.9 dBi, and 1.9 dBi at 433 MHz, 868 MHz, and 915 MHz, respectively, with an omnidirectional H-plane radiation pattern and a radiation efficiency above 90% across the three frequency bands. The fabrication and measurement of the antenna have been carried out, and the results of simulation and measurements are compared. The agreement among the simulation and measurement results confirms the design's accuracy and the antenna's suitability for LoRa IoT applications, particularly in providing a compact, flexible, and energy efficient communication solution for different LoRa frequency bands.


Assuntos
Comunicação , Ásia , Simulação por Computador , Europa (Continente) , Sorogrupo
3.
Micromachines (Basel) ; 14(3)2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36984990

RESUMO

High-gain DC-DC converters are being drastically utilized in renewable energy generation systems, such as photovoltaic (PV) and fuel cells (FC). Renewable energy sources (RES) persist with low-level output voltage; therefore, high-gain DC-DC converters are essentially integrated with RES for satisfactory performance. This paper proposes a non-isolated high-gain non-inverting interleaved DC-DC boost converter. The proposed DC-DC converter topology is comprised of two inductors and these are charging and discharging in series and parallel circuit configurations. The voltage multiplier technique is being utilized to produce high gain. The proposed topology is designed to operate in three modes of operation. Three switches are operated utilizing two distinct duty ratios to avoid the extreme duty ratio while having high voltage gain. Owing to its intelligent design, the voltage stress on the switches is also significantly reduced where the maximum stress is only 50% of the output voltage. The proposed converter's steady-state analysis with two distinct duty ratios is thoroughly explored. Furthermore, a 160 W 20/400 V prototype is developed for performance analysis and validation. The converter topology can generate output voltage with a very high voltage gain of 20, which is verified by the prototype. Moreover, a high efficiency of 93.2% is attained by the proposed converter's hardware prototype.

4.
Nanomaterials (Basel) ; 13(4)2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36839033

RESUMO

Graphene and its derivatives have emerged as peerless electrode materials for energy storage applications due to their exclusive electroactive properties such as high chemical stability, wettability, high electrical conductivity, and high specific surface area. However, electrodes from graphene-based composites are still facing some substantial challenges to meet current energy demands. Here, we applied one-pot facile solvothermal synthesis to produce nitrogen-doped reduced graphene oxide (N-rGO) nanoparticles using an organic solvent, ethylene glycol (EG), and introduced its application in supercapacitors. Electrochemical analysis was conducted to assess the performance using a multi-channel electrochemical workstation. The N-rGO-based electrode demonstrates the highest specific capacitance of 420 F g-1 at 1 A g-1 current density in 3 M KOH electrolyte with the value of energy (28.60 Whkg-1) and power (460 Wkg-1) densities. Furthermore, a high capacitance retention of 98.5% after 3000 charge/discharge cycles was recorded at 10 A g-1. This one-pot facile solvothermal synthetic process is expected to be an efficient technique to design electrodes rationally for next-generation supercapacitors.

5.
Micromachines (Basel) ; 13(11)2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36422388

RESUMO

In this research, a novel antenna array named Linearly arranged Concentric Circular Antenna Array (LCCAA) is proposed, concerning lower beamwidth, lower sidelobe level, sharp ability to detect false signals, and impressive SINR performance. The performance of the proposed LCCAA beamformer is compared with geometrically identical existing beamformers using the conventional technique where the LCCAA beamformer shows the lowest beamwidth and sidelobe level (SLL) of 12.50° and -15.17 dB with equal elements accordingly. However, the performance is degraded due to look direction error, for which robust techniques, fixed diagonal loading (FDL), optimal diagonal loading (ODL), and variable diagonal loading (VDL), are applied to all the potential arrays to minimize this problem. Furthermore, the LCCAA beamformer is further simulated to reduce the sidelobe applying tapering techniques where the Hamming window shows the best performance having 17.097 dB less sidelobe level compared to the uniform window. The proposed structure is also analyzed under a robust tapered (VDL-Hamming) method which reduces around 69.92 dB and 48.39 dB more sidelobe level compared to conventional and robust techniques. Analyzing all the performances, it is clear that the proposed LCCAA beamformer is superior and provides the best performance with the proposed robust tapered (VDL-Hamming) technique.

6.
Preprint em Inglês | bioRxiv | ID: ppbiorxiv-208371

RESUMO

After a breakdown notified in Wuhan, China in December 2019, COVID-19 is declared as pandemic diseases. To the date more than 13 million confirmed cases and more than half a million are dead around the world. This virus also attached Malaysia in its immature stage where 8718 cases were confirmed and 122 were declared as death. Malaysia responsibly controlled the spread by enforcing MCO. Hence, it is required to visualize the pattern of Covid-19 spread. Also, it is necessary to estimate the impact of the enforced prevention measures. In this paper, an infectious disease dynamic modeling (SEIR) is used to estimate the epidemic spread in Malaysia. The main assumption is to update the reproduction number Rt with respect to the implemented prevention measures. For a time-frame of five month, the Rt was assumed to vary between 2.9 and 0.3. Moreover, the manuscript includes two possible scenarios: the first will be the extension of the stricter measures all over the country, and the second will be the gradual lift of the lock-down. After implementing several stages of lock-down we have found that the estimated values of the Rt with respect to the strictness degree varies between 0.2 to 1.1. A continuous strict lock-down may reduce the Rt to 0.2 and accordingly the estimated active cases will be reduced to 20 by the beginning of September 2020. In contrast, the second scenario considers a gradual lift of the enforced prevention measures by the end of June 2020, here we have considered three possible outcomes according to the MCO relaxation. Thus, the estimated values of Rt = 0.7, 0.9, 1.1, which shows a rapid increase in the number of active cases. The implemented SEIR model shows a close resemblance with the actual data recorded from 10, March till 7, July 2020. Author summaryConceptualization, A.A.A; methodology, A.A.A, N.M; validation, A.A.A, N.M; formal analysis, A.A.A; investigation, N.M, A.A.A; resources, G.E.M.A, L.T; data collection, L.T, N.M; writing--original draft preparation, A.A.A, L.T, G.E.M.A, N.M; writing--review and editing, V.S.A, S.C.D, B.S.G, P.S, S.A.B.M.Z, N.M; visualization, N.M; supervision, V.S.A; project administration, V.S.A. All authors have read and agreed to the published version of the manuscript

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