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1.
Heliyon ; 10(8): e29761, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38681634

RESUMO

Bast fibers are defined as those obtained from the outer cell layers of the bast of various plant families. They are finding use in textile applications and are widely used as reinforcements for green composites, as bast fibers are perceived as "sustainable". There is a growing demand for bast fibers across the world due to their renewable and biodegradable nature. The bast fibers are mainly composed of cellulose, which potentially considers the growing techniques, harvesting and extraction processes of bast fibers most used to produce fibers with appropriate quality to apply in the daily lives of modern men and women in contemporary society. This review paper looks at many aspects of natural fibers, with a focus on plant bast fibers, including their impact on prehistoric and historical society. This review shows that bast fibers are competitive compared to man-made fibers in many applications, but variability in mechanical properties and low tenacity may limit their use in high-strengthh composites and extend to, particularly in aerospace, automotive, packaging, building industries, insulation, E-composites (Eco composites), geotextiles and many other applications are currently being explored. Considering, important characteristics of bast fibers include physical, mechanical, and chemical properties. This makes bast fibers one of the most important classes of plant fibers to use as reinforcing agents in thermosetting/thermoplastic polymer matrices. And the effect of bast fibers as reinforcement in the properties of ECO-composites, GREEN-composites, BIO-composites, lightweight composites. Bast fibers play an important role in sustainability, the preservation of the health of the environment, the well-being of the next generation, and even the daily lives of men and women in the contemporary world.

2.
Microorganisms ; 12(4)2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38674753

RESUMO

The present work assessed the experimental susceptibility of Nyssomyia antunesi and Lutzomyia longipalpis to Leishmania (Viannia) lainsoni and L. (V.) lindenbergi. A L. (Leishmania) chagasi-Lu. longipalpis combination was used as a susceptible control. Wild-caught Ny. antunesi and laboratory-bred Lu. longipalpis were membrane-fed on blood with a 5 × 106/mL log-phase promastigote culture suspension and dissected on days 2 and 8 post-blood meal (pbm) for analysis focused on the assessment of parasitoses, as well as placement and promastigote morphotyping. Survival curves were constructed. In all combinations, promastigotes were observed on day 8 pbm. For both Leishmania species, in Lu. longipalpis, the presence of parasites was observed up to the stomodeal valve, while in Ny. antunesi, the presence of parasites was observed up to the cardia. There were no significant differences in parasitosis between L. (V.) lainsoni and L. (V.) lindenbergi in either Ny. antunesi or Lu. longipalpis. Six morphological promastigote forms were distinguished in Giemsa-stained gut smears. The survival curves of all combinations decreased and were affected differently by several Lu. longipalpis-parasite combinations, as well with Lu. longipalpis-uninfected blood. These findings stress Lu. longipalpis as experimentally susceptible to Leishmania spp. and suggest the putative susceptibility of Ny. antunesi to L. (V.) lainsoni and L. (V.) lindenbergi.

3.
J Synchrotron Radiat ; 31(Pt 3): 547-556, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38630437

RESUMO

Fourth-generation synchrotron storage rings represent a significant milestone in synchrotron technology, offering outstandingly bright and tightly focused X-ray beams for a wide range of scientific applications. However, due to their inherently tight magnetic lattices, these storage rings have posed critical challenges for accessing lower-energy radiation, such as infrared (IR) and THz. Here the first-ever IR beamline to be installed and to operate at a fourth-generation synchrotron storage ring is introduced. This work encompasses several notable advancements, including a thorough examination of the new IR source at Sirius, a detailed description of the radiation extraction scheme, and the successful validation of our optical concept through both measurements and simulations. This optimal optical setup has enabled us to achieve an exceptionally wide frequency range for our nanospectroscopy experiments. Through the utilization of synchrotron IR nanospectroscopy on biological and hard matter samples, the practicality and effectiveness of this beamline has been successfully demonstrated. The advantages of fourth-generation synchrotron IR sources, which can now operate with unparalleled stability as a result of the stringent requirements for producing low-emittance X-rays, are emphasized.

4.
EClinicalMedicine ; 71: 102547, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38524919

RESUMO

Background: Identification of unvaccinated children is important for preventing deaths due to infections. Number of siblings and birth order have been postulated as risk factors for zero-dose prevalence. Methods: We analysed nationally representative cross-sectional surveys from 85 low and middle-income countries (2010-2020) with information on immunisation status of children aged 12-35 months. Zero-dose prevalence was defined as the failure to receive any doses of DPT (diphtheria-pertussis-tetanus) vaccine. We examined associations with birth order and the number of siblings, adjusting for child's sex, maternal age and education, household wealth quintiles and place of residence. Poisson regression was used to calculate zero-dose prevalence ratios. Findings: We studied 375,548 children, of whom 13.7% (n = 51,450) were classified as zero-dose. Prevalence increased monotonically with birth order and with the number of siblings, with prevalence increasing from 11.0% for firstborn children to 17.1% for birth order 5 or higher, and from 10.5% for children with no siblings to 17.2% for those with four or more siblings. Adjustment for confounders attenuated but did not eliminate these associations. The number of siblings remained as a strong risk factor when adjusted for confounders and birth order, but the reverse was not observed. Among children with the same number of siblings, there was no clear pattern in zero-dose prevalence by birth order; for instance, among children with two siblings, the prevalence was 13.0%, 14.7%, and 13.3% for firstborn, second, and third-born, respectively. Similar results were observed for girls and boys. 9513 families had two children aged 12-35 months. When the younger sibling was unvaccinated, 61.9% of the older siblings were also unvaccinated. On the other hand, when the younger sibling was vaccinated, only 5.9% of the older siblings were unvaccinated. Interpretation: The number of siblings is a better predictor than birth order in identifying children to be targeted by immunization campaigns. Zero-dose children tend to be clustered within families. Funding: Gavi, the Vaccine Alliance.

5.
Artigo em Inglês | MEDLINE | ID: mdl-38521741

RESUMO

Failures in orthognathic surgery are associated with different factors, including those related to untreated or undiagnosed preoperative temporomandibular joint (TMJ) disorders. This systematic review aimed to assess potential alterations in the condylar head following orthognathic surgery. A systematic search for randomised controlled trials and retrospective studies was performed. For inclusion in the review, studies had to meet the following eligibility criteria according to the PICO framework: Patients: patients with orthognathic deformity and temporomandibular dysfunction (or temporomandibular osteoarthritis); Intervention: patients submitted to orthognathic surgery concomitantly with TMJ disjunction; Control: patients undergoing only orthognathic surgery with or without presurgical data; and Outcome: changes in temporomandibular joint position and volume. Nine studies met all the inclusion criteria and were selected for qualitative analysis. The results of this review show that simultaneous articular disc repositioning and orthognathic surgery provide better results in patients with preoperatively diagnosed condylar osteoarthritic changes. In conclusion, condylar remodelling (resorption/deposition) and its extent are determined by the direction of condylar displacement during surgery. Other factors such as age are also associated with the development of condylar resorption.

6.
Lupus ; 33(6): 574-586, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38506239

RESUMO

BACKGROUND: Antineutrophil cytoplasmatic antibodies (ANCA) have been detected in patients with systemic lupus erythematosus (SLE). In this study, we investigated the presence of ANCA in a sample of Brazilian SLE patients and its possible associations with clinical and serological outcomes. Additionally, we reviewed the literature of on ANCA in SLE. RESULTS: The presence of ANCA was detected in 130 patients using indirect immunofluorescence (IIF). The test was positive in 29.9% of the cases (17.6% pANCA and 11.5% cANCA). Male sex and peripheral vasculitis were more prevalent in the ANCA-positive sample. cANCA was associated with lupus anticoagulant and pANCA had a positive association with peripheral vasculitis and a negative association with anti- SSB/La antibodies. In the 22 studies included in the literature review, a wide range of ANCA positivity was found (13% to 81.1% by IIF and 0 to 22.2% by ELISA). ANCA was associated with renal damage in the Asian population. Although other associations have been found in isolated studies, they were not consistently reported. CONCLUSIONS: The ANCA prevalence found in this Brazilian sample was within the range reported in the literature and these autoantibodies were more frequent in males and in patients with vasculitis. The literature showed controversial results on the association between ANCA and SLE disease activity or clinical characteristics.


Assuntos
Lúpus Eritematoso Sistêmico , Vasculite , Humanos , Masculino , Anticorpos Anticitoplasma de Neutrófilos , Estudos Transversais , Brasil/epidemiologia , Lúpus Eritematoso Sistêmico/complicações , Mieloblastina , Vasculite/complicações , Anticorpos Antinucleares
7.
Heliyon ; 10(5): e26706, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38434283

RESUMO

For the first time, the current work has carried out a chemical treatment of a novel ligno-cellulose fiber that is extracted from the bark of an unexplored plant of Careya arborea. Careya arborea (CA), a flowering tree known for its green berries, thrives in the Indian subcontinent and Afghanistan. This research was focused on extracting fibers from the bark of the Cary tree for the first time to corroborate the influence of chemical treatment on its different characteristics. These CA fibers have a high proportion of cellulose, consisting of 71.17 wt percent, together with 27.86 wt percent of hemicellulose, and a reduced density of 1140 kg/m3, making them a suitable candidate for creating lightweight applications in a variety of industries. Chemical treatment has done on the cay fiber with the concentrations of NaOH 5 (wt%), 10 (wt%), and 15 (wt%) solution mixture to improve their characteristics. Estimated the difference between Chemically processed and non-processed Cary fibers and corroborated in results. We performed a number of experiments, including FTIR, XRD, SEM, EDAX, AFM, and TGA, to fully comprehend the changing properties. Chemical testing showed that cellulose changed from its non-crystalline state to cellulose, proving that the treatment was successful in changing the fibre structure. Additionally, the thermo-gravimetric examination showed higher thermal stability 248 °C-325 °C and a rise in the crystallinity index, indicating the treated fibers' improved potential for high-temperature applications. The treated Cary fibers exhibited excellent surface properties, promising improved adhesion, mechanical performance, offering lightweight and sustainable solutions for diverse applications.

8.
J Chem Phys ; 160(6)2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38341792

RESUMO

Traditional theories of the nuclear magnetic resonance (NMR) autocorrelation function for intra-molecular dipole pairs assume a single-exponential decay, yet the calculated autocorrelation of realistic systems displays a rich, multi-exponential behavior, resulting in anomalous NMR relaxation dispersion (i.e., frequency dependence). We develop an approach to model and interpret the multi-exponential intra-molecular autocorrelation using simple, physical models within a rigorous statistical mechanical development that encompasses both rotational diffusion and translational diffusion in the same framework. We recast the problem of evaluating the autocorrelation in terms of averaging over a diffusion propagator whose evolution is described by a Fokker-Planck equation. The time-independent part admits an eigenfunction expansion, allowing us to write the propagator as a sum over modes. Each mode has a spatial part that depends on the specified eigenfunction and a temporal part that depends on the corresponding eigenvalue (i.e., correlation time) with a simple, exponential decay. The spatial part is a probability distribution of the dipole pair, analogous to the stationary states of a quantum harmonic oscillator. Drawing inspiration from the idea of inherent structures in liquids, we interpret each of the spatial contributions as a specific molecular mode. These modes can be used to model and predict the NMR dipole-dipole relaxation dispersion of fluids by incorporating phenomena on the molecular level. We validate our statistical mechanical description of the distribution in molecular modes with molecular dynamics simulations interpreted without any relaxation models or adjustable parameters: the most important poles in the Padé-Laplace transform of the simulated autocorrelation agree with the eigenvalues predicted by the theory.

9.
Med Teach ; : 1-6, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38295519

RESUMO

INTRODUCTION: The development of clinical skills requires the appropriate use of self-regulated learning (SRL). Students' use of key SRL processes as they perform a clinical skill can be identified by SRL microanalysis and used to provide feedback. SRL-microanalysis feedback only on students' key SRL processes has not been previously researched for developing clinical skills. The aim of this study was to investigate whether SRL-microanalysis feedback only on students' key SRL processes can improve both their use of SRL and their clinical skill performance. METHODS: Twenty-three final year medical students with no experience in the clinical skill required for mechanical ventilation participated in this study. Key SRL processes and clinical skill performance were measured before and after SRL microanalysis feedback. RESULTS: Overall, we found an improvement in the key SRL processes of planning and monitoring of performance, with a significant difference in monitoring. We also found an increase in students' clinical skill performance. DISCUSSION: This study, which is the first in clinical skills, demonstrated that SRL microanalysis feedback only on key SRL processes can improve both students' SRL and their clinical skill performance. studies are recommended with a great number of students and across a variety of clinical skills.

11.
J Med Entomol ; 61(2): 498-503, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38157321

RESUMO

The present study aimed to assess different light sources for sampling phlebotomines (Diptera: Psychodidae) from Bosque Rodrigues Alves, a forested park surrounded by the urban area of Belém in the Brazilian Amazon. Centers for Disease Control traps, baited with blue, green, and warm white light-emitting diodes (LEDs), as test group, and incandescent light, as control group, were used. The electromagnetic spectra and luminous intensities of the light sources were characterized. Fractional vegetation cover at each sampling site was also estimated. Abundance, richness, rarefaction curves, Shannon and Simpson diversity indices, phlebotomines/trap/hour, and phlebotomines/trap/night were estimated and compared. The light sources of the test group presented greater luminous intensity than the control, but were similar to each other. There were no differences in vegetation cover at each site. A total of 1,346 phlebotomines comprising 11 species were sampled. The most abundant species were as follows: Nyssomyia antunesi (Coutinho, 1939), Trichophoromyia ubiquitalis (Mangabeira, 1942), Bichromomyia flaviscutellata (Mangabeira, 1942), and Th. brachipyga (Mangabeira, 1942). Light traps with LEDs had richness, abundance, and Shannon diversity indices similar to those obtained with incandescent light. The warm white LED had a higher Simpson's index than the other light sources. Phlebotomine responses to incandescent light were similar to those to LEDs in most analyses, confirming the applicability of these light sources as alternative devices for entomological surveillance. Low consumption ensures greater autonomy of the traps, providing better operability during fieldwork.


Assuntos
Psychodidae , Animais , Psychodidae/fisiologia , Brasil , Parques Recreativos , Insetos Vetores , Florestas
12.
J Virol ; 97(12): e0130923, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38092658

RESUMO

IMPORTANCE: Giant viruses are noteworthy not only due to their enormous particles but also because of their gigantic genomes. In this context, a fundamental question has persisted: how did these genomes evolve? Here we present the discovery of cedratvirus pambiensis, featuring the largest genome ever described for a cedratvirus. Our data suggest that the larger size of the genome can be attributed to an unprecedented number of duplicated genes. Further investigation of this phenomenon in other viruses has illuminated gene duplication as a key evolutionary mechanism driving genome expansion in diverse giant viruses. Although gene duplication has been described as a recurrent event in cellular organisms, our data highlights its potential as a pivotal event in the evolution of gigantic viral genomes.


Assuntos
Evolução Molecular , Duplicação Gênica , Vírus Gigantes , Genoma Viral , Vírus Gigantes/genética , Filogenia
13.
J Water Health ; 21(12): 1834-1846, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38153715

RESUMO

The world is not on track to achieve universal access to safely managed water by 2030, and access is substantially lower in rural areas. This Sustainable Development Goal target and many other global indicators rely on the classification of improved water sources for monitoring access. We aimed to investigate contamination in drinking water sources, comparing improved and unimproved sources in urban and rural settings. We used data from Multiple Indicator Cluster Surveys, which tested samples from the household water source and a glass of water for Escherichia coli contamination across 38 countries. Contamination was widespread and alarmingly high in almost all countries, settings, and water sources, with substantial inequalities between and within countries. Water contamination was found in 51.7% of households at the source and 70.8% in the glass of water. Some improved sources (e.g., protected wells and rainwater) were as likely to be contaminated as unimproved sources. Some sources, like piped water, were considerably more likely to be contaminated in rural than urban areas, while no difference was observed for others. Monitoring water contamination along with further investigation in water collection, storage, and source classification is essential and must be expanded to achieve universal access to safely managed water.


Assuntos
Água Potável , Escherichia coli , Poluição da Água , Poços de Água
15.
BMC Public Health ; 23(1): 2353, 2023 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-38017390

RESUMO

BACKGROUND: Although it is well known that obesity is frequently associated with reduced levels of habitual physical activity (HPA), which contributes to determining severe oxidative stress and inflammatory state, this association is however unknown in preschoolers so far. This study aimed to investigate the association between biomarkers of redox status and cytokines with different patterns of HPA according to the adiposity of preschoolers. METHODS: A cross-sectional study was conducted in 50 preschoolers (25 overweight/obese, OW/OB and 25 eutrophic, EU), matched for age, sex, economic level, and maternal education. Total antioxidant capacity (TAC), superoxide dismutase (SOD) and catalase (CAT) activities, substances reactive to thiobarbituric acid (TBARS), soluble tumor necrosis factor receptors (sTNFRs), and leptin levels were evaluated. HPA levels were evaluated by accelerometry (ActiGraph GT9X accelerometer). Correlation, multiple linear regression, and partial least squares regression analysis were used to determine the association between redox status biomarkers and cytokines with different patterns of HPA (HPA level, bouts of moderate to vigorous physical activity [MVPA], and multivariate pattern of HPA) in EU and OW/OB preschoolers. RESULTS: OW/OB preschoolers had lower CAT activity, higher levels of TAC, TBARS, and cytokines, and similar levels of HPA to EU preschoolers. In EU preschoolers, SOD activity exhibited a stronger negative association with moderate intensity ranges of HPA (R2 = 0.18), and negative correlation with sTNFRs (r = -0.40 to -0.46). TBARS had a stronger positive association with ranges of light intensity in the multivariate pattern of HPA (R2 = 0.10). In OW/OB preschoolers, the HPA multivariate associative pattern was predominantly from vigorous intensity ranges. Thus, SOD activity had a positive association with the multivariate pattern of HPA (R2 = 0.38) and MVPA bouts (ß [95% CI] = 0.457 [0.0026. 0.0576]). TAC had a negative association with the multivariate pattern of HPA (R2 = 0.38) and MVPA bouts (ß [95% CI] = -0.718 [-0.0025. -0.0003]). Additionally, leptin levels were lower in OW/OB preschoolers engaged in vigorous physical activity (VPA) (8000-9999 counts/min) for longer periods of time. CONCLUSION: The results of this study indicate that OW/OB preschoolers have higher levels of oxidative stress biomarkers and pro-inflammatory cytokines compared to EU preschoolers. Moreover, VPA may exert antioxidative and anti-inflammatory effects in OW/OB preschoolers.


Assuntos
Leptina , Sobrepeso , Humanos , Estudos Transversais , Citocinas , Substâncias Reativas com Ácido Tiobarbitúrico , Índice de Massa Corporal , Obesidade , Exercício Físico , Oxirredução , Biomarcadores , Análise Multivariada , Superóxido Dismutase
16.
An Acad Bras Cienc ; 95(suppl 3): e20210560, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37820119

RESUMO

The Lange glacier is an outlet glacier situated in the Admiralty Bay, King George Island, Peninsula Antarctica. It retreated about 1 km since the 1950s. Although recent observations do not show any significant change at the ice-ocean margin, it is not clear whether this glacier has reached a new steady state or whether it is still adjusting to new climate conditions. By combining a three-dimensional glacier model with satellite and in-situ datasets, we investigate the sensitivity of Lange glacier to perturbations in flow rate factor, friction coefficient, surface mass balance, and calving front position. The (time-dependent) perturbation experiments show that the glacier is more sensitive to changes in surface mass balance and in flow rate factor. These results suggest that the climate variability of this region plays an important role on the glacier's dynamics, and that measurements of englacial temperature will improve the reliability of future modeling efforts. Our model shows that the position of the ice front exerts a strong control on the glacier flux. In our time-dependent simulation, the impacts of the observed front retreat on the glacier's dynamics persist beyond the present date. This suggests that Lange is likely still adjusting to past perturbations at its terminus.


Assuntos
Clima , Camada de Gelo , Regiões Antárticas , Reprodutibilidade dos Testes , Temperatura
17.
Artigo em Inglês | MEDLINE | ID: mdl-37754654

RESUMO

To describe trends of dentist-prescribed non-steroidal anti-inflammatory drugs (NSAIDs) and analgesics, from January 2011 to December 2021, as well as to examine the relationship between these trends and characteristics of public oral health services in Minas Gerais, Brazil. In this time-series analysis, all drugs were classified according to the Anatomical Therapeutic Chemical classification system. Drugs categorized as NSAIDs (M01A), and other analgesics and antipyretics (N02B) were included for analysis. The outcome was the number of Defined Daily Doses (DDDs)/1000 inhabitants/year for NSAIDs and analgesics in each town. Covariates referred to characteristics of public oral health services, such as coverage, estimates of dental procedures, and frequency of toothache. Linear time-series regression models were used to determine the influence of covariates on the outcome. Overall, there were 58,482 prescriptions of NSAIDs recorded in thirty-eight towns, while 47,499 prescriptions of analgesics in forty-three towns. For each year, there was a 0.38 (p < 0.001), and 0.28 (p < 0.001) increase in the average log of DDD/1000 inhabitants/year for NSAIDs and analgesics, respectively. A positive association was detected between toothache (p < 0.001) and the prescription of NSAIDs. Over the eleven years, there was a general rising trend in the prescriptions. Toothache was the only characteristic of public oral health services associated with the prescription rates of NSAIDs, implying that as the frequency of toothaches increase, so do the prescriptions of NSAIDs in the studied towns.


Assuntos
Prescrições de Medicamentos , Odontalgia , Humanos , Brasil/epidemiologia , Odontalgia/tratamento farmacológico , Odontalgia/epidemiologia , Anti-Inflamatórios não Esteroides/uso terapêutico , Projetos de Pesquisa
18.
Vet Med Sci ; 9(6): 2463-2474, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37654028

RESUMO

BACKGROUND: A cohort study for 2 years period analysed the prevalence, incidence and clinical-immunological features of canine Leishmania (L.) chagasi-infection in 316 mongrel dogs in a visceral leishmaniasis-endemic area in Pará State, Brazil. OBJECTIVE/METHODS: Diagnosis of infection was performed by the indirect fluorescent antibody test (IFAT-IgG), the leishmanin skin test (LST) and a parasite search (from the popliteal lymph node aspiration) at the beginning of the study and at 6, 12 and 24 months intervals. RESULTS: IFAT/LST revealed three immune profiles of infection: (I) IFAT(+) /LST(-) (81), (II) IFAT(-) /LST(+) (17) and (III) IFAT(+) /LST(+) (13). Prevalence of profiles I, II and III were 25.6, 5.4 and 4.1%, and an overall prevalence 35.1%. Incidence of profiles I, II and III were 5.4, 0.3 and 0.0%, and an overall incidence 5.7% dogs per month. Incidence at the age ranges <1 year, ≥1 year, <7 years and ≥7 years evidenced a highest rate in the age range <1 year (6.6% dogs per month). Parasitological diagnosis was positive in 19% dogs at the prevalence (85.7% profile I), and in 11% at the incidence (100% profile I). The clinical picture of 179 infected dogs showed 145 (81%) of profile I (82% subclinical); 21 (11.7%) of profile II (100% subclinical); and 13 (7.3%) of profile III (84.6% subclinical). Conversion from subclinical to sick dogs was higher (p < 0.05) in profile I (40.2%) than in profiles II (5.8%) and III (9%). Immunological conversion showed that only 3.2% of profile I dogs (prevalence) converted to LST(+) (two at the end of the first 6 months and 1 after 24 months), while 82.3% of profile II dogs converted to IFAT(+) (11 in the first 6 months, whereas three after 12 months). A 100% death rate was observed in dogs from profile I alone. CONCLUSION: These results reinforce the need of adopting preventive strategies against CVL as early as in the first semester of the dog's life.


Assuntos
Doenças do Cão , Leishmaniose Visceral , Humanos , Cães , Animais , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/veterinária , Brasil/epidemiologia , Estudos de Coortes , Prevalência , Incidência , Doenças do Cão/diagnóstico
19.
Heliyon ; 9(8): e18805, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37576310

RESUMO

Shear thickening fluids (STFs) refer to non-Newtonian fluids of the dilatant variety, wherein their viscosity experiences a significant surge with an escalation in the shear rate. In this investigative work, the friction behavior between yarns (pull-out) and absorption of static and kinetic energy during the phenomenon of friction between yarns in STFs are performed by monophase (MP-STF) adding nano SiO2 and dual-phase (MP-STF) adding carbon nanotubes. The ρ-Aramid fabrics were reinforced via the "foulard process", and carried out on MP-STF, and DP-STF/ρ-Aramid-impregnated fabrics to evaluate and compare with the enhancement in interfacial friction properties between yarns. The results showed that DP-STF has more significant than MP-STF and MP-STF in ultimate load, kinetic shear stress, static shear stress, and friction energy level effects. The DP-STF exhibits various friction enhancement mechanisms at the yarn interface, leading to higher absorption of static and kinetic energy related to interfacial friction, as indicated by the results obtained. Furthermore, the DP-STF/ρ-Aramid impregnated fabrics exhibited ultimate load (22.23 ± 0.522 N), kinetic shear stress (35.73 ± 0.850 MPa*100), static shear stress (36.28 ± 0.900 MPa*100), and friction energy level (610.33 ± 0.250). Increased ultimate load (581.7% and 180.7%), kinetic shear stress (621.4% and 174.6%), static shear stress (550.5% and 159.1%), and friction energy level (680.2 and 186.7%) compared to WT-STF and MP-STF, respectively. The current discoveries hold immense potential for various applications in the fields of engineering and smart material technologies. These applications span a multiplicity of industries, including sports products, medical advancements, space technology, as well as protective and shielding products.

20.
Heliyon ; 9(8): e18784, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37560668

RESUMO

This article presents a study on the tensile properties of knitted fabrics commonly employed in polymeric matrix textile composites. The key mechanical parameters investigated include stress (Pa), strain, Young's modulus (Pa), and work of rupture (J). The knitted fabrics were developed using the Cixing Knitting System software and subsequently manufactured using a double jersey (electronic) flat knitting machine. The primary objective of this research was to explore the impact of various factors on the mechanical behavior of these knitted fabrics. The factors studied were wale and course directions, float stitch density, loop length (cm), and the type of synthetic knitting yarns used (100% polyester and 100% polyamide) along with different combinations of knitting yarns (100% cotton and 67% polyester/33% cotton hybrid). The adopted ASTM D 5034 standard, Response Surface Methodology (RSM), and Analysis of Variance (ANOVA) were employed to evaluate the mechanical performance of these fabric structures. The findings of the study revealed that the statistical adjustment of the data set for stress, strain, Young's modulus, and work of rupture in knitted fabric structures significantly reduced the standard deviations for mechanical responses. This information holds particular significance as it pertains to the frequent use of these knitted fabric structures as reinforcement in textile-reinforced composite materials. Overall, this study sheds light on the mechanical behavior in structures of knitted fabrics used in polymeric matrix composites, providing valuable insights for the design and optimization of advanced textile-based materials.

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