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1.
Chem Rec ; 24(3): e202300308, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38200590

RESUMO

The transition to sustainable transportation has fueled the need for innovative electric vehicle (EV) charging solutions. Building Integrated Photovoltaics (BIPV) systems have emerged as a promising technology that combines renewable energy generation with the infra-structure of buildings. This paper comprehensively reviews the BIPV system for EV charging, focusing on its technology, application, and performance. The review identifies the gaps in the existing literature, emphasizing the need for a thorough examination of BIPV systems in the context of EV charging. A detailed review of BIPV technology and its application in EV charging is presented, covering aspects such as the generation of solar cell technology, BIPV system installation, design options and influencing factors. Furthermore, the review examines the performance of BIPV systems for EV charging, focusing on energy, economic, and environmental parameters and their comparison with previous studies. Additionally, the paper explores current trends in energy management for BIPV and EV charging, highlighting the need for effective integration and recommending strategies to optimize energy utilization. Combining BIPV with EV charging provides a promising approach to power EV chargers, enhances building energy efficiency, optimizes the building space, reduces energy losses, and decreases grid dependence. Utilizing BIPV-generated electricity for EV charging provides electricity and fuel savings, offers financial incentives, and increases the market value of the building infrastructure. It significantly lowers greenhouse gas emissions associated with grid and vehicle emissions. It creates a closed-loop circular economic system where energy is produced, consumed, and stored within the building. The paper underscores the importance of effective integration between Building Integrated Photovoltaics (BIPV) and Electric Vehicle (EV) charging, emphasizing the necessity of innovative grid technologies, energy storage solutions, and demand-response energy management strategies to overcome diverse challenges. Overall, the study contributes to the knowledge of BIPV systems for EV charging by presenting practical energy management, effectiveness and sustainability implications. It serves as a valuable resource for researchers, practitioners, and policymakers working towards sustainable transportation and energy systems.

2.
Sensors (Basel) ; 24(8)2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38676185

RESUMO

The interest in precise point positioning techniques using smartphones increased with the launch of the world's first dual-frequency L1/L5 GNSS smartphone, Xiaomi Mi 8. The smartphone GNSS antenna is low-cost, sensitive to multipath, and limited by physical space and design. The main purpose of this work is to determine the mechanical location and antenna performance in terms of radiation pattern in an anechoic chamber using a Vector Network Analyzer (VNA) and robotic positioning platform by varying the elevation and azimuth angles between the transmitter and smartphone GNSS antennas; the power received and satellite visibility are developed in an outdoor scenario. The results show a Planar Inverted-F Antenna with an omnidirectional radiation pattern without gain. The L1/E1/B1 and L5/E5a/B2a GNSS antennas are physically located at the top face of the screen, with dimensions of 48 × 17 mm and 60 × 13 mm, respectively. With the screen with line-of-sight toward the sky, L5 satellites have a better signal-noise ratio (SNR), unlike the back side, which loses 99% of the data in the PPP solution. Under multipath scenarios, the L1 GNSS smartphone antenna works with 25% less power than the GPS user segment recommendation, showing high sensitivity to track weak signals.

3.
Sensors (Basel) ; 23(11)2023 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-37299856

RESUMO

Three-dimensional (3D) reconstruction of objects using the polarization properties of diffuse light on the object surface has become a crucial technique. Due to the unique mapping relation between the degree of polarization of diffuse light and the zenith angle of the surface normal vector, polarization 3D reconstruction based on diffuse reflection theoretically has high accuracy. However, in practice, the accuracy of polarization 3D reconstruction is limited by the performance parameters of the polarization detector. Improper selection of performance parameters can result in large errors in the normal vector. In this paper, the mathematical models that relate the polarization 3D reconstruction errors to the detector performance parameters including polarizer extinction ratio, polarizer installation error, full well capacity and analog-to-digital (A2D) bit depth are established. At the same time, polarization detector parameters suitable for polarization 3D reconstruction are provided by the simulation. The performance parameters we recommend include an extinction ratio ≥ 200, an installation error ∈ [-1°, 1°], a full-well capacity ≥ 100 Ke-, and an A2D bit depth ≥ 12 bits. The models provided in this paper are of great significance for improving the accuracy of polarization 3D reconstruction.


Assuntos
Imageamento Tridimensional , Modelos Teóricos , Imageamento Tridimensional/métodos , Simulação por Computador
4.
Trop Anim Health Prod ; 54(5): 324, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36169771

RESUMO

The study evaluated effects of L-serine on lipid profile, performance, carcass weight and small intestinal parameters in heat-stressed broiler chickens subjected to feed restriction. Broiler chickens were divided into four groups, comprising 30 each. Group 1, feed restriction (FR); Group 2, feed restriction + L-serine (200 mg/kg) (FR + L-serine); Group 3, ad libitum (AL); Group 4, ad libitum + L-serine (200 mg/kg) (AL + L-serine). L-serine was administered orally from days 1 to 14, and feed restriction was performed on days 7-14. Serum harvested from blood samples on days 21, 28 and 35 was evaluated for lipid profile. Feed and water intake, live weight gain, organ and carcass weight were measured. At 35 days old, broiler chickens (n = 7) per group were sacrificed to evaluate small intestinal morphology. Temperature-humidity index in the pen (30.88 ± 0.81) was above thermoneutral zone, indicating that chickens were subjected to heat stress. Concentrations of low-density lipoprotein, total cholesterol and total triglycerides were lower (p < 0.05), while higher concentration of high-density lipoprotein was recorded in L-serine groups than in the controls. Feed intake and live weight gain on day 35 in L-serine groups were higher (p < 0.05) than in controls. In L-serine groups, liver, spleen, pancreas and heart weight were higher, but abdominal fat was lower than in FR and AL groups. Villus height:crypt height ratio and area of villus surface were highest in L-serine groups than any other group. In conclusion, L-serine decreased low-density lipoprotein, increased feed intake, live weight, organ and carcass weight, villus height:crypt height ratio and villus surface area.


Assuntos
Galinhas , Transtornos de Estresse por Calor , Ração Animal/análise , Animais , Colesterol , Dieta/veterinária , Suplementos Nutricionais , Transtornos de Estresse por Calor/veterinária , Lipoproteínas HDL , Lipoproteínas LDL , Estações do Ano , Serina , Triglicerídeos , Aumento de Peso
5.
Metabolomics ; 17(6): 51, 2021 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-34021818

RESUMO

INTRODUCTION: Bioactive constituents of medicinal-aromatic plants used as feed additives may affect the metabolic profile and oxidative stability of hen eggs. OBJECTIVES: To determine the effects of dietary supplementation with a mixture of dried oregano, thyme, sideritis tea and chamomile on laying hen performance, egg quality parameters, and oxidative stability in the egg yolk were monitored. METHODS: In this trial 432 hens were allocated in two treatments (unsupplemented vs. supplemented with the mixture) and fed for 42 days. Eggs were collected at the end of the trial period, egg yolk was separated, extracted, and the total phenolic content (TPC) and oxidative stability was measured. Furthermore, LC-MS metabolic profile of eggs was studied and pathway analysis was elaborated in MetaboAnalyst to facilitate annotation of features. RESULTS: Overall, egg production and feed conversion ratio were not affected by the supplementation. However, eggs from the supplemented treatment showed improved shell thickness and strength, and yolk resistance to oxidation. Moreover, LC-MS metabolomic analysis of egg yolk of supplemented and unsupplemented layers showed significant variations and tight clustering in unsupervised principal component analysis due to different chemical profiling of egg yolk. LC-MS study showed that secondary metabolites of aromatic plants did not transfer into yolk, nevertheless the feed supplementation impacted the pathway metabolism of tyrosine, phenylalanine, propanate, and the biosynthesis of aminoacyl-tRNA, phenylalanine, tyrosine and tryptophan. CONCLUSIONS: The dietary supplementation of layers with a mixture of dried medicinal aromatic plants affected shell thickness and strength, the lipid and protein oxidative stability and increased tyrosine and phenylalanine content in eggs.


Assuntos
Origanum , Sideritis , Thymus (Planta) , Ração Animal/análise , Animais , Camomila , Galinhas , Cromatografia Líquida de Alta Pressão , Dieta , Suplementos Nutricionais/análise , Feminino , Fenilalanina , Extratos Vegetais , Chá , Tirosina
6.
BMC Med Imaging ; 21(1): 165, 2021 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-34749660

RESUMO

BACKGROUND: The commonly used NEMA IEC Body phantom has a number of defects, hindering its application for detecting micro-lesions and measuring the performance parameters of computed tomography (CT). This study aimed to propose a PET/CT phantom designed by National Institute of Metrology (NIM), China, which is capable of simultaneously testing the performance of PET and CT systems, and to evaluate the quality of imaging. METHODS: The phantom developed in the present study, the NIM PET/CT phantom, is composed of a PET imaging module and a CT imaging module, and these modules are connected together through bolts, which can simultaneously measure the imaging performance of PET and CT systems. Hot spheres were filled with 4:1 sphere-to-background activity concentration using 18F-fluorodeoxyglucose (18F-FDG), and cold spheres were filled with non-radioactive water. We compared the results of imaging obtained from the NIM PET/CT phantom and the NEMA IEC Body phantom to assess their diagnostic efficacy. In order to evaluate the generalization ability of the NIM PET/CT phantom, three different PET/CT systems were used to scan on the same scanning protocol. To evaluate the effects of image reconstruction algorithms on image quality assessment, ordered subset expectation maximization (OSEM), OSEM-point-spread function (PSF), OSEM-TOF, and OSEM-PSF-TOF algorithms were employed. RESULTS: The imaging quality of the NIM PET/CT phantom and the NEMA IEC Body phantom was relatively consistent. The NIM PET/CT phantom could detect 7 mm spheres without influencing the imaging quality. It was found that PSF reconstruction exhibited to reduce the speed of convergence, the contrast and background variability of spheres (13-28 mm) were significantly improved after two iterations. In addition to improve the image contrast and background variability, TOF could markedly improve the overall image quality and instrument detection limit. TOF-PSF could noticeably reduce noise level, enhance imaging details, and improve quality of imaging. CONCLUSIONS: The results showed that in comparison with the NEMA IEC Body phantom, the NIM PET/CT phantom outperformed in evaluating the PET image quality of micro-lesions and the performance parameters of CT.


Assuntos
Desenho de Equipamento , Imagens de Fantasmas , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , China
7.
Aging Clin Exp Res ; 33(6): 1529-1537, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32930988

RESUMO

BACKGROUND: While sensor-based daily physical activity (DPA) gait assessment has been demonstrated to be an effective measure of physical frailty and fall-risk, the repeatability of DPA gait parameters between different days of measurement is not clear. AIMS: To evaluate test-retest reliability (repeatability) of DPA gait performance parameters, representing the quality of walking, and quantitative gait measures (e.g. number of steps) between two separate days of assessment among older adults. METHODS: DPA was acquired for 48-h from older adults (age ≥ 65 years) using a tri-axial accelerometer. Continuous walking bouts (≥ 60 s) were identified from acceleration data and used to extract gait performance parameters, including time- and frequency-domain gait parameters, representing walking speed, variability, and irregularity. To assess repeatability, intraclass correlation coefficient (ICC) was calculated using two-way mixed effects F-test models for day-1 vs. day-2 as the independent random effect. Repeatability tests were performed for all participants and also within frailty groups (non-frail and pre-frail/frail identified using Fried phenotype). RESULTS: Data was analyzed from 63 older adults (29 non-frail and 34 pre-frail/frail). Most of the time- and frequency-domain gait performance parameters showed good to excellent repeatability (ICC ≥ 0.70), while quantitative parameters, including number of steps and walking duration showed poor repeatability (ICC < 0.30). Among majority of the gait performance parameters, we observed higher repeatability among the pre-frail/frail group (ICC > 0.78) compared to non-frail individuals (0.39 < ICC < 0.55). CONCLUSION: Gait performance parameters, showed higher repeatability compared to quantitative measures. Higher repeatability among pre-frail/frail individuals may be attributed to a reduced functional capacity for performing more intense and variable physical tasks. TRIAL REGISTRATION: The clinical trial was retrospectively registered on June 18th, 2013 with ClinicalTrials.gov, identifier NCT01880229.


Assuntos
Fragilidade , Idoso , Idoso Fragilizado , Fragilidade/diagnóstico , Marcha , Avaliação Geriátrica , Humanos , Reprodutibilidade dos Testes , Caminhada
8.
BMC Geriatr ; 20(1): 164, 2020 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-32375700

RESUMO

BACKGROUND: Frailty is a highly recognized geriatric syndrome resulting in decline in reserve across multiple physiological systems. Impaired physical function is one of the major indicators of frailty. The goal of this study was to evaluate an algorithm that discriminates between frailty groups (non-frail and pre-frail/frail) based on gait performance parameters derived from unsupervised daily physical activity (DPA). METHODS: DPA was acquired for 48 h from older adults (≥65 years) using a tri-axial accelerometer motion-sensor. Continuous bouts of walking for 20s, 30s, 40s, 50s and 60s without pauses were identified from acceleration data. These were then used to extract qualitative measures (gait variability, gait asymmetry, and gait irregularity) and quantitative measures (total continuous walking duration and maximum number of continuous steps) to characterize gait performance. Association between frailty and gait performance parameters was assessed using multinomial logistic models with frailty as the dependent variable, and gait performance parameters along with demographic parameters as independent variables. RESULTS: One hundred twenty-six older adults (44 non-frail, 60 pre-frail, and 22 frail, based on the Fried index) were recruited. Step- and stride-times, frequency domain gait variability, and continuous walking quantitative measures were significantly different between non-frail and pre-frail/frail groups (p < 0.05). Among the five different durations (20s, 30s, 40s, 50s and 60s), gait performance parameters extracted from 60s continuous walks provided the best frailty assessment results. Using the 60s gait performance parameters in the logistic model, pre-frail/frail group (vs. non-frail) was identified with 76.8% sensitivity and 80% specificity. DISCUSSION: Everyday walking characteristics were found to be associated with frailty. Along with quantitative measures of physical activity, qualitative measures are critical elements representing the early stages of frailty. In-home gait assessment offers an opportunity to screen for and monitor frailty. TRIAL REGISTRATION: The clinical trial was retrospectively registered on June 18th, 2013 with ClinicalTrials.gov, identifier NCT01880229.


Assuntos
Fragilidade , Idoso , Idoso Fragilizado , Fragilidade/diagnóstico , Marcha , Avaliação Geriátrica , Humanos , Caminhada
9.
Chirality ; 31(8): 583-591, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31185131

RESUMO

Praziquantel (PZQ) composes a regular medicine available in a tablet form to fight schistosomiasis and just half of its mass is composed by the active principle (L-PZQ), the other half, D-PZQ, is frequently associated to a strong bitter taste. Moreover, optically pure L-PZQ derivatives could be used in studies about adult and juvenile worms' resistance. Nowadays, these studies use racemic PZQ (rac-PZQ) as starting point. The D-PZQ, which would be discarded, could be racemized, coming back as feed concentration in the process. The present work aims to get L-PZQ and D-PZQ with high optical purities (more than 97%) and productivity (more than 253 g kgads -1  day-1 ) towards semipreparative scale for researches involving L-PZQ, L-PZQ derivatives, and D-PZQ racemization. In order to achieve this goal, a built-in-house simulated moving bed chromatographic unit with the cellulose tris (3-chloro-4-methylphenylcarbamate) (Chiralcel OZ) as chiral stationary phase (CSP) was used to investigate different scenarios of separation according to a well-known design method called triangle theory. In all scenarios investigated, at least one of the outlet streams presented high optically purity for one of the enantiomers. Comparison with literature showed superior performance of our unit even at racemic mixture concentrations that were 10 times lower than the racemic concentrations found in literature.

10.
J Synchrotron Radiat ; 25(Pt 4): 1093-1105, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29979170

RESUMO

Lens-coupled indirect X-ray imaging detectors have the advantage of high resolution and the disadvantage of low detection efficiency. Using thicker single-crystalline films (SCFs) can improve the detection efficiency. However, the image quality will become worse due to the degradation of the point spread function (PSF) and modulation transfer function (MTF). This disadvantage can be improved by deconvolution with the PSF, which is unknown. In this article, a method was established to acquire the PSF based on a simulation of the imaging process for a lens-coupled indirect X-ray imaging detector. Because the structural parameters of commercial lenses cannot usually be obtained, the PSFs were calculated from lens performance parameters. PSFs were calculated using the conditions of 12 keV X-ray energy, 10× and 40× magnification objectives and 4.6 µm- and 20 µm-thick GGG:Tb scintillators. These were then used to deconvolve images of an Xradia resolution test pattern taken under the same conditions. The results show that after deconvolution the MTF had been clearly improved for both the 4.6 µm- and 20 µm-thick SCFs, indicating that the image has better quality than before deconvolution. Furthermore, a PSF deconvolution was performed on mouse brain tissue projection images, and the original and deconvolution projection images were used to perform computed-tomography reconstruction; the result proved that the method was effective for improving the image quality of low-contrast samples. Therefore, this method shows promise in allowing the use of thick SCFs to improve the detection efficiency while maintaining good image quality.

11.
Sensors (Basel) ; 17(9)2017 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-28858252

RESUMO

Electrical Impedance Tomography (EIT) is a medical imaging technique that has been recently used to realize stretchable pressure sensors. In this method, voltage measurements are taken at electrodes placed at the boundary of the sensor and are used to reconstruct an image of the applied touch pressure points. The drawback with EIT-based sensors, however, is their low spatial resolution due to the ill-posed nature of the EIT reconstruction. In this paper, we show our performance evaluation of different EIT drive patterns, specifically strategies for electrode selection when performing current injection and voltage measurements. We compare voltage data with Signal-to-Noise Ratio (SNR) and Boundary Voltage Changes (BVC), and study image quality with Size Error (SE), Position Error (PE) and Ringing (RNG) parameters, in the case of one-point and two-point simultaneous contact locations. The study shows that, in order to improve the performance of EIT based sensors, the electrode selection strategies should dynamically change correspondingly to the location of the input stimuli. In fact, the selection of one drive pattern over another can improve the target size detection and position accuracy up to 4.7% and 18%, respectively.

12.
Trop Anim Health Prod ; 49(1): 71-77, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27730448

RESUMO

A study was conducted on 37 randomly selected broiler poultry farmers in Rwanda to characterize the production system using pre-tested semi-structured questionnaires. The data were processed in SPSS and presented as means, percentages and ranges in tables and text. All respondents kept Cobb breed and young stock was mainly (73 %) imported from abroad. The majority of respondents were males (68 %) and most farmers had attended only primary level of education (40.5 %). Most of the farms were in the peri-urban (48.6 %) and urban (37.8 %) areas and hired male youth (62.2 %) mainly aged 19-35 years. The majority of respondents (68 %) kept less than 500 birds per batch. Recordkeeping was well practiced (91.9 %) and (62.6 %) had permanent poultry houses and all farmers used deep litter system. Purchased feedstuffs were reportedly (92 %) mixed at farm level as the main feed resource. Maize bran was reported (97.06 %) the main, basal feedstuff. The mortality rates of chick and growers were 12.3 and 9.4 %, respectively. The slaughter age was reportedly 60 days with an average dressing percentage of 75.67 %. The main challenges reported were scarcity and unaffordability of quality feeds (59.5 %), lack of market access (45 %) and lack of credit (21 %). The farmers had various views on improving broiler production in Rwanda ranging from establishing feed processing industries 62.2 %, improving marketing facilities 35.1 %, increasing availability of day-old chick and access credit 27 %, to intensification of farmer training 16.2 %.


Assuntos
Criação de Animais Domésticos/métodos , Doenças das Aves Domésticas/epidemiologia , Adulto , Animais , Cruzamento , Galinhas , Feminino , Humanos , Masculino , Aves Domésticas , Ruanda , Inquéritos e Questionários , População Urbana , Adulto Jovem
13.
Sensors (Basel) ; 16(8)2016 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-27509499

RESUMO

Accelerated degradation testing (ADT) is an efficient technique for evaluating the lifetime of a highly reliable product whose underlying failure process may be traced by the degradation of the product's performance parameters with time. However, most research on ADT mainly focuses on a single performance parameter. In reality, the performance of a modern product is usually characterized by multiple parameters, and the degradation paths are usually nonlinear. To address such problems, this paper develops a new s-dependent nonlinear ADT model for products with multiple performance parameters using a general Wiener process and copulas. The general Wiener process models the nonlinear ADT data, and the dependency among different degradation measures is analyzed using the copula method. An engineering case study on a tuner's ADT data is conducted to demonstrate the effectiveness of the proposed method. The results illustrate that the proposed method is quite effective in estimating the lifetime of a product with s-dependent performance parameters.

14.
Sensors (Basel) ; 16(4)2016 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-27049391

RESUMO

Smartphone sensors are being increasingly used in mobile applications. The performance of sensors varies considerably among different smartphone models and the development of a cross-platform mobile application might be a very complex and demanding task. A publicly accessible resource containing real-life-situation smartphone sensor parameters could be of great help for cross-platform developers. To address this issue we have designed and implemented a pilot participatory sensing application for measuring, gathering, and analyzing smartphone sensor parameters. We start with smartphone accelerometer and gyroscope bias and noise parameters. The application database presently includes sensor parameters of more than 60 different smartphone models of different platforms. It is a modest, but important start, offering information on several statistical parameters of the measured smartphone sensors and insights into their performance. The next step, a large-scale cloud-based version of the application, is already planned. The large database of smartphone sensor parameters may prove particularly useful for cross-platform developers. It may also be interesting for individual participants who would be able to check-up and compare their smartphone sensors against a large number of similar or identical models.

15.
Bioprocess Biosyst Eng ; 38(11): 2063-75, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26227509

RESUMO

Global variables play a key role in evaluation of the performance of pneumatic bioreactors and provide criteria to assist in system selection and design. The purpose of this work was to use experimental data and computational fluid dynamics (CFD) simulations to determine the global performance parameters gas holdup ([Formula: see text]) and volumetric oxygen transfer coefficient (k L a), and conduct an analysis of liquid circulation velocity, for three different geometries of pneumatic bioreactors: bubble column, concentric-tube airlift, and split tube airlift. All the systems had 5 L working volumes and two Newtonian fluids of different viscosities were used in the experiments: distilled water and 10 cP glycerol solution. Considering the high oxygen demand in certain types of aerobic fermentations, the assays were carried out at high flow rates. In the present study, the performances of three pneumatic bioreactors with different geometries and operating with two different Newtonian fluids were compared. A new CFD modeling procedure was implemented, and the simulation results were compared with the experimental data. The findings indicated that the concentric-tube airlift design was the best choice in terms of both gas holdup and volumetric oxygen transfer coefficient. The CFD results for gas holdup were consistent with the experimental data, and indicated that k L a was strongly influenced by bubble diameter and shape.


Assuntos
Reatores Biológicos , Simulação por Computador , Glicerol/química , Modelos Químicos , Água/química
16.
Heliyon ; 10(10): e31506, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38818199

RESUMO

Neo-formed contaminants (NFCs) are common in many foods, especially those subjected to high-temperature processing. Among these contaminants, products arising from the Maillard reaction, sugar reduction, thermal degradation of polyphenols and lipid oxidation, including acrylamide, furan, furfuryl alcohol, and hydroxymethylfurfural, are consistently linked to potential neoplastic effects. NFCs are found in globally traded commodities like coffee and cocoa, posing a significant risk due to their frequent consumption by consumers. A direct correlation exists between consumption frequency, exposure levels, and health risks. Hence, it's crucial to establish reliable methods to determine levels in both matrices, aiming to mitigate their formation and minimise risks to consumers. This review offers a comprehensive examination, discussion, and identification of emerging trends and opportunities to enhance existing methodologies for extracting and quantifying NFCs in coffee and cocoa. By presenting an in-depth analysis of performance parameters, we aim to guide the selection of optimal extraction techniques for quantifying individual NFCs. Based on the reviewed data, headspace extraction is recommended for furan, while solid and dispersive solid phase extractions are preferred for acrylamide when quantified using gas and liquid chromatography, respectively. However, it is worth noting that the reported linearity tests for certain methods did not confirm the absence of matrix effects unless developed through standard addition, leading to uncertainties in the reported values. There is a need for further research to verify method parameters, especially for determining NFCs like furfuryl alcohol. Additionally, optimising extraction and separation methods is essential to ensure complete compound depletion from samples. Ideally, developed methods should offer comprehensive NFC determination, reduce analysis time and solvent use, and adhere to validation parameters. This review discusses current methods for extracting and quantifying NFCs in coffee and cocoa, highlighting emerging trends and emphasising the need to improve existing techniques, especially for compounds like furfuryl alcohol.

17.
Artigo em Inglês | MEDLINE | ID: mdl-38565819

RESUMO

Dwindling of fossil fuels and the global climate change has prompted civilization to look into alternate energy sources. This has led to explore inexhaustible and sustainable resources in the domain of renewable energy. Among all sources renewable energy, biofuel produced from biomass has great prospect for energy security as well as environmental safety over fossil fuels. The present work tries to explore the performance attributes and emission characteristics of a CI engine utilizing spirulina microalgae biodiesel blend comprising of 20% algae biodiesel blended with 80% diesel. This blend is tested in a diesel engine at varying engine load conditions of 20%, 40%, 60%, 80%, and 100% at variable injection timing of 20°, 23°, 25°, and 28° bTDC, respectively at compression ratio of 18. Based on experimental results, the peak brake thermal efficiency for injection timing of 20°, 23°, 25°, and 28° bTDC at 100% engine load were observed to be 26.79%, 23.77%, 24.77%, and 25.09%, respectively for the biodiesel blend in comparison to 27.76% of diesel mode whereas the emissions levels were found to minimum at 20° bTDC. On the part of emission, the average drop in CO emissions for injection timing of 20°, 23°, 25°, and 28° bTDC were found to be 53.46%, 43.71%, 44.34%, and 50.31%, respectively for biodiesel blend as compared to diesel mode. For the same setting, in comparison diesel mode, the average fall in HC emissions were found to be 42.32%, 34.13%, 30.37%, and 37.54%, respectively, and the rise of NOx emissions were found to be 8.06%, 5.55%, 3.51%, and 3.04%, respectively. Response surface methodology was applied for optimization of operating parameters of the algae biodiesel blend run diesel engine. The desirability based study revealed that at 85.19% engine load and injection timing of 20° bTDC were optimal operation settings which resulted in engine performance of 25.44% brake thermal efficiency. The emission level at this setting was observed to be reduced to 27.68 ppm CO, 1.60% CO2, 24.65 ppm HC, and 182.15 ppm NOx.

18.
Front Vet Sci ; 10: 1276754, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37881447

RESUMO

This study aims to evaluate the efficacy of humic acid (HA) from worm compost as an adsorbent for aflatoxin B1 (AFB1) in turkey poults. The experiment involved the inclusion of 0.25% (w/w) HA in the diet of turkey poults consuming aflatoxin-contaminated feed (250 ng AFB1/g). A total of 350 1-day-old female Nicholas-700 turkey poults were randomly allocated to five equal groups: negative control (basal diet); positive control (basal diet + 250 ng AFB1/g; HA (basal diet + 0.25% HA); HA + AFB1 (basal diet + HA + 250 ng AFB1/g); and zeolite + AFB1 (basal diet + 0.25% zeolite + 250 ng AFB1/g). Each group had seven replicates of 10 poults (n = 70). The impact of HA addition was evaluated in terms of performance parameters, relative organ weights, liver histological lesions, and serum biochemical and hematological constituents. In general, the addition of HA improved body weight (BW), body weight gain (BWG), and feed conversion rate (FCR). Furthermore, HA effectively mitigated the toxic effects caused by AFB1 in the majority of the analyzed variables. The results indicated that HA effectively counteracted the AFB1-induced toxic effects in turkey poults. Based on these findings, it can be concluded that HA is capable of removing AFB1 from the contaminated diet.

20.
Disabil Rehabil ; : 1-6, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37480166

RESUMO

PURPOSE: The Dix-Hallpike test is recommended to diagnose Benign Paroxysmal Positional Vertigo (BPPV). This research aimed to quantify the movement of a healthy subject during the Dix-Hallpike test and determine what factors contribute to performance variation from the recommended head position with 20° cervical extension, 45° cervical rotation, and a brisk movement velocity. MATERIALS AND METHODS: Examiners performed the Dix-Hallpike test 10 times. The examinee's movement was recorded with Qualisys and processed with Visual3D. The proportion of variation in test performance within examiners, between examiners, and due to examiner position was calculated. RESULTS: Thirteen participants, 54% male and mean age 40, performed 50 cranial and 77 lateral Dix-Hallpike tests. Head position differed significantly from the recommendations with the cranial tests for extension (mean difference [MD] = 11.6°, p < 0.001) and rotation (MD = 4.8°, p < 0.001) and with lateral tests for extension (MD = 13.3°, p < 0.001). The largest proportion of variation was between examiners (60-91%), followed by within-examiners (3-16%). The examiner position contributed to 20% of the variation in the cervical rotation achieved. Tests lasted, on average, 1.80 s. CONCLUSIONS: Differences within and between examiners visually estimating the Dix-Hallpike test endpoints may impede BPPV diagnosis accuracy.


Vertigo diagnosis with the Dix-Hallpike may be improved by reducing inter-examiner differences with head positioning and velocity.With Dix-Hallpike testing, examiners should consider a cranial orientation relative to the examinee to better achieve the recommended head positioning.The cranial Dix-Hallpike and encouraging briskness as tolerated by the examinee should be emphasized with teaching the maneuver.

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