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1.
J Am Pharm Assoc (2003) ; : 102091, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38604477

RESUMO

BACKGROUND: Community pharmacies are ideal venues for pre-exposure prophylaxis (PrEP) delivery. Pharmacists and pharmacy-based PrEP delivery programs have the potential to improve access. OBJECTIVES: This study elicited preferences for attributes of a hypothetical community pharmacy-based PrEP delivery program among US men who have sex with men (MSM) and assessed predictors of their preferences. METHODS: Data were collected via a cross-sectional anonymous survey of US MSM, who were aged 18-65 years, not transgender, reported HIV status negative/unknown, and PrEP eligible. A discrete choice experiment was conducted with seven attributes of a pharmacy-based PrEP program: initial PrEP eligibility screening mode, location for HIV tests, timing for HIV test results, PrEP decision-making style, location of PrEP consultations, PrEP medication fill method, and mode for ongoing monitoring. Latent class analysis was performed to analyze preference heterogeneity. Multinomial logistic regression assessed predictors of latent class membership. RESULTS: This study included 390 MSM. Time to receive HIV test results was the most important attribute; receiving results on the same day had the highest preference. The next most important attribute was PrEP screening mode; online questionnaires were the most preferred. Respondents' preferences clustered into four classes: 1) "Same day results and online monitoring" (SDROM) group (63.1%), 2) "Consumerist decision-making" (CDM) group (16.2%), 3) "Self-screening (online questionnaire)" (SOQ) group (11.3%), and 4) "Same day results preferring" (SDRP) group (9.5%). Hispanic MSM [adjusted odds ratio (aOR)=0.31, 95% CI (0.12-0.84), p=0.020], MSM of other races [aOR=0.38, 95% CI (0.15-0.97), p=0.044] vs. White MSM; and those having a sexually transmitted disease recently [aOR=0.37, 95% CI (0.16-0.85), p=0.018], had lower odds of being in the CDM group vs. the SDROM group. CONCLUSIONS: MSM's preferences for a pharmacy-based PrEP program are heterogeneous. Same day results for HIV tests and online PrEP screening are key components when designing a community pharmacy-based PrEP program.

2.
Nat Commun ; 15(1): 2138, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38459015

RESUMO

The advanced patterning process is the basis of integration technology to realize the development of next-generation high-speed, low-power consumption devices. Recently, area-selective atomic layer deposition (AS-ALD), which allows the direct deposition of target materials on the desired area using a deposition barrier, has emerged as an alternative patterning process. However, the AS-ALD process remains challenging to use for the improvement of patterning resolution and selectivity. In this study, we report a superlattice-based AS-ALD (SAS-ALD) process using a two-dimensional (2D) MoS2-MoSe2 lateral superlattice as a pre-defining template. We achieved a minimum half pitch size of a sub-10 nm scale for the resulting AS-ALD on the 2D superlattice template by controlling the duration time of chemical vapor deposition (CVD) precursors. SAS-ALD introduces a mechanism that enables selectivity through the adsorption and diffusion processes of ALD precursors, distinctly different from conventional AS-ALD method. This technique facilitates selective deposition even on small pattern sizes and is compatible with the use of highly reactive precursors like trimethyl aluminum. Moreover, it allows for the selective deposition of a variety of materials, including Al2O3, HfO2, Ru, Te, and Sb2Se3.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38411045

RESUMO

BACKGROUND: The aim of this paper was to identify the most appropriate allometric scaling model for expressing aerobic fitness, determined by maximal oxygen consumption (VO2max), that would allow comparisons across differing body types. METHODS: VO2max and body composition data were collected from untrained non-obese and obese participants (N.=126). Allometric models were created using body mass (BM), fat-free mass (FFM), and leg FFM (LFFM) to determine the goodness-of-fit using the Akaike Information Criterion (AIC). RESULTS: Allometric scaled exponents adjusted for BM, FFM and LFFM were 0.67, 0.68 and 0.55, respectively. VO2max scaled to BM was 22% higher in non-obese individuals. Scaled to LFFM, V VO2max was only 7.5% higher in non-obese individuals as compared to obese individuals. Data showed a positive correlation (r=0.28; P=0.009) between VO2max and BM for non-obese participants and a negative correlation (r=-0.39; P=0.014) for obese participants. AIC values showed the LFFM model as the best fit (AICc = 0 "substantial support) and the AIC differences for FFM and BM were both >10 "no support" for the model (12.1 and 28.2, respectively). CONCLUSIONS: Interpretation of aerobic power and comparisons would be most appropriate when allometrically scaled to the metabolically active tissue (LFFM). Bias is introduced when scaling to BM and comparing individuals of various body compositions.

4.
ACS Nano ; 18(1): 819-828, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38153349

RESUMO

As semiconductor scaling continues to reach sub-nanometer levels, two-dimensional (2D) semiconductors are emerging as a promising candidate for the post-silicon material. Among these alternatives, Bi2O2Se has risen as an exceptionally promising 2D semiconductor thanks to its excellent electrical properties, attributed to its appropriate bandgap and small effective mass. However, unlike other 2D materials, growth of large-scale Bi2O2Se films with precise layer control is still challenging due to its large surface energy caused by relatively strong interlayer electrostatic interactions. Here, we present the successful growth of a wafer-scale (∼3 cm) Bi2O2Se film with precise thickness control down to the monolayer level on TiO2-terminated SrTiO3 using metal-organic chemical vapor deposition (MOCVD). Scanning transmission electron microscopy (STEM) analysis confirmed the formation of a [BiTiO4]1- interfacial structure, and density functional theory (DFT) calculations revealed that the formation of [BiTiO4]1- significantly reduced the interfacial energy between Bi2O2Se and SrTiO3, thereby promoting 2D growth. Additionally, spectral responsivity measurements of two-terminal devices confirmed a bandgap increase of up to 1.9 eV in monolayer Bi2O2Se, which is consistent with our DFT calculations. Finally, we demonstrated high-performance Bi2O2Se field-effect transistor (FET) arrays, exhibiting an excellent average electron mobility of 56.29 cm2/(V·s). This process is anticipated to enable wafer-scale applications of 2D Bi2O2Se and facilitate exploration of intriguing physical phenomena in confined 2D systems.

5.
ACS Mater Au ; 3(5): 501-513, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-38089098

RESUMO

The thiospinel group of nickel cobalt sulfides (NixCo3-xS4) are promising materials for energy applications such as supercapacitors, fuel cells, and solar cells. Solution-processible nanoparticles of NixCo3-xS4 have advantages of low cost and fabrication of high-performance energy devices due to their high surface-to-volume ratio, which increases the electrochemically active surface area and shortens the ionic diffusion path. The current approaches to synthesize NixCo3-xS4 nanoparticles are often based on hydrothermal or solvothermal methods that are difficult to scale up safely and efficiently and that preclude monitoring the reaction through aliquots, making optimization of size and dispersity challenging, typically resulting in aggregated nanoparticles with polydisperse sizes. In this work, we report a scalable "heat-up" method to colloidally synthesize NixCo3-xS4 nanoparticles that are smaller than 15 nm in diameter with less than 15% in size dispersion, using two inexpensive, earth-abundant sulfur sources. Our method provides a reliable synthetic pathway to produce phase-pure, low-dispersity, gram-scale nanoparticles of ternary metal sulfides. This method enhances the current capabilities of NixCo3-xS4 nanoparticles to meet the performance demands to improve renewable energy technologies.

6.
Polymers (Basel) ; 15(20)2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37896369

RESUMO

In this study, preliminary simulations were performed to manufacture thermoplastic composites that can be processed by injection. For analysis, a basalt particulate-polymer composite model was manufactured and its elastic modulus, shear modulus, thermal expansion coefficient, and thermal conductivity were predicted using finite-element analysis (FEA) and micromechanics. Polypropylene (PP), polyamide 6, polyamide 66, and polyamide (PA) were employed as the polymer matrix, with the variations in their properties investigated based on the volume fraction of basalt. The polymer-basalt composite's properties were analyzed effectively using FEA and the micromechanics model. FEA was performed by constructing a 3D model based on the homogenization technique to analyze the effective properties. The micromechanics model was analyzed numerically using the mixture rule, and the Mital, Guth, and Halpin-Tsai models. As a result, it is best to analyze the effective properties of polymer-basalt composites using the Halpin-Tsai model, and it is necessary to conduct a comparative analysis through actual experiments. In the future, actual composite materials need to be developed and evaluated based on the findings of this study.

7.
J Am Chem Soc ; 145(31): 17406-17419, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37525439

RESUMO

While certain ternary spinel oxides have been well-explored with colloidal nanochemistry, notably the ferrite spinel family, ternary manganese (Mn)-based spinel oxides have not been tamed. A key composition is cobalt (Co)-Mn oxide (CMO) spinel, CoxMn3-xO4, that, despite exemplary performance in multiple electrochemical applications, has few reports in the colloidal literature. Of these reports, most show aggregated and polydisperse products. Here, we describe a synthetic method for small, colloidally stable CMO spinel nanocrystals with tunable composition and low dispersity. By reacting 2+ metal-acetylacetonate (M(acac)2) precursors in an amine solvent under an oxidizing environment, we developed a pathway that avoids the highly reducing conditions of typical colloidal synthesis reactions; these reducing conditions typically push the system toward a monoxide impurity phase. Through surface chemistry studies, we identify organic byproducts and their formation mechanism, enabling us to engineer the surface and obtain colloidally stable nanocrystals with low organic loading. We report a CMO/carbon composite with low organic contents that performs the oxygen reduction reaction (ORR) with a half-wave potential (E1/2) of 0.87 V vs RHE in 1.0 M potassium hydroxide at 1600 rpm, rivaling previous reports for the highest activity of this material in ORR electrocatalysis. We extend the general applicability of this procedure to other Mn-based spinel nanocrystals such as Zn-Mn-O, Fe-Mn-O, Ni-Mn-O, and Cu-Mn-O. Finally, we show the scalability of this method by producing inorganic nanocrystals at the gram scale.

8.
Korean J Radiol ; 24(7): 647-659, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37404107

RESUMO

OBJECTIVE: The study was conducted to investigate the effect of correct occlusion of the left atrial appendage (LAA) on intracardiac blood flow and thrombus formation in patients with atrial fibrillation (AF) using four-dimensional (4D) flow magnetic resonance imaging (MRI) and three-dimensional (3D)-printed phantoms. MATERIALS AND METHODS: Three life-sized 3D-printed left atrium (LA) phantoms, including a pre-occlusion (i.e., before the occlusion procedure) model and correctly and incorrectly occluded post-procedural models, were constructed based on cardiac computed tomography images from an 86-year-old male with long-standing persistent AF. A custom-made closed-loop flow circuit was set up, and pulsatile simulated pulmonary venous flow was delivered by a pump. 4D flow MRI was performed using a 3T scanner, and the images were analyzed using MATLAB-based software (R2020b; Mathworks). Flow metrics associated with blood stasis and thrombogenicity, such as the volume of stasis defined by the velocity threshold (|V̅| < 3 cm/s), surface-and-time-averaged wall shear stress (WSS), and endothelial cell activation potential (ECAP), were analyzed and compared among the three LA phantom models. RESULTS: Different spatial distributions, orientations, and magnitudes of LA flow were directly visualized within the three LA phantoms using 4D flow MRI. The time-averaged volume and its ratio to the corresponding entire volume of LA flow stasis were consistently reduced in the correctly occluded model (70.82 mL and 39.0%, respectively), followed by the incorrectly occluded (73.17 mL and 39.0%, respectively) and pre-occlusion (79.11 mL and 39.7%, respectively) models. The surface-and-time-averaged WSS and ECAP were also lowest in the correctly occluded model (0.048 Pa and 4.004 Pa-1 , respectively), followed by the incorrectly occluded (0.059 Pa and 4.792 Pa-1 , respectively) and pre-occlusion (0.072 Pa and 5.861 Pa-1 , respectively) models. CONCLUSION: These findings suggest that a correctly occluded LAA leads to the greatest reduction in LA flow stasis and thrombogenicity, presenting a tentative procedural goal to maximize clinical benefits in patients with AF.


Assuntos
Apêndice Atrial , Fibrilação Atrial , Trombose , Masculino , Humanos , Idoso de 80 Anos ou mais , Apêndice Atrial/diagnóstico por imagem , Velocidade do Fluxo Sanguíneo/fisiologia , Hemodinâmica , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/cirurgia , Imageamento por Ressonância Magnética/métodos , Trombose/diagnóstico por imagem , Trombose/complicações
9.
J Psychiatr Res ; 165: 115-122, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37490844

RESUMO

OBJECTIVES: This study assessed trends in depression symptoms, executive function, and their association across age among older adults. Subgroup comparisons were made between older adults meeting and not meeting physical activity guidelines on variables and associations of interest. METHODS: Participants (n = 2473) were older adults ages 60 to 79 from the 2011-2014 National Health and Nutrition Examination Survey. Depression symptoms, executive function, and physical activity were assessed, and weighted time-varying effect modeling was used for analyses. RESULTS: Depression symptoms were most severe at age 62 followed by a modest decline before a second peak around age 67. Executive function was highest at age 60 and declined steadily through age 77. Depression symptoms and executive function were negatively associated, but the strength and significance of this association varied with age. Older adults meeting physical activity guidelines had increased executive function and less severe depression symptoms, and meeting physical activity guidelines buffered the association between depression symptoms and executive function at key ages during older adulthood. CONCLUSIONS: Differences by age should be considered when designing and implementing health programs and treatments focusing on mental health and cognition in older adulthood. Encouraging moderate-intensity physical activity may help protect older adults from depression-related cognitive decline.


Assuntos
Depressão , Função Executiva , Humanos , Idoso , Pessoa de Meia-Idade , Depressão/psicologia , Inquéritos Nutricionais , Cognição , Exercício Físico
10.
Nutrients ; 15(4)2023 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-36839165

RESUMO

Existing resilience measures have psychometric shortcomings, and there is no current gold-standard resilience measure. Previous work indicates adults enrolled in a health coaching program may benefit from a resilience measure that is tailored and contextualized to this sample. This two-part study aimed to develop and evaluate a resilience instrument focused on health behavior change in adults in a health coaching program. Two studies were conducted to (1) create a resilience instrument (Health Resilience Profile; HRP) specific to adults attempting health behavior change (n = 427; female = 83.8%; age = 44.5 ± 11.9 years) and to (2) optimize the instrument performance using Rasch analysis (n = 493; female = 62.1%; age = 49.8 ± 12.5 years). Study 1 identified two issues: (1) four unacceptable misfit items and (2) inappropriate rating scale functioning. Study 2 evaluated an improved instrument based on the outcome of study 1 resulting in one more misfit item, and unidimensionality was supported. The new four-category rating scale functioned well. The item-person map indicated that item difficulty distribution was well matched to participants' resilience level, and items were free from measurement error. Finally, items did not show differential item functioning across age, sex, alcohol use, and obesity status. The 18-item HRP is optimized for adults in a health coaching program.


Assuntos
Qualidade de Vida , Adulto , Humanos , Feminino , Pessoa de Meia-Idade , Inquéritos e Questionários , Psicometria/métodos , Obesidade , Reprodutibilidade dos Testes
11.
Aging Ment Health ; 27(3): 653-662, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35341422

RESUMO

OBJECTIVES: This study aimed to (1) investigate age-associated trends in depression and cognition, (2) determine whether the association between depression and cognition varies across age, and (3) test whether this association is moderated by different levels of physical activity among older U.S. immigrant adults aged 60 to 80 years. METHODS: Using national data on elderly U.S. immigrants (N = 375) from the 2011-2014 NHANES, we employed weighted intercept-only linear time-varying effect modeling (TVEM) and weighted linear TVEM to address our research questions. RESULTS: Weighted intercept-only linear TVEM indicated no trend in depression, but its mean peaked at age 67. Cognition consistently decreased with age, reaching its lowest point at age 78. Weighted linear TVEM revealed a significant inverse association between depression and cognition at some age ranges, with the strongest association at around age 66. Yet, we did not find the moderational relation of physical activity to this age-varying association. CONCLUSIONS: Although we observed a significant inverse relationship between depression and cognition at a certain age point, physical activity did not moderate the age-varying association. Understanding of age-varying effects on the depression-cognition interaction will promote prevention efforts targeting aging immigrant populations at highest risk for these health outcomes. Further work is needed to test moderating effects of other health behaviors on this association across age.Supplemental data for this article is available online at https://doi.org/10.1080/13607863.2022.2056139 .


Assuntos
Depressão , Emigrantes e Imigrantes , Idoso , Humanos , Depressão/epidemiologia , Inquéritos Nutricionais , Cognição , Exercício Físico
12.
Res Sports Med ; 31(2): 137-156, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34304646

RESUMO

The purpose was to summarize the studies examining the contralateral protective effect on the maximal strength in the subsequent bout of muscle-damaging exercise. The literature search was conducted through CINAHL plus, SportDiscus, and PubMed. Hedge's g effect size (ES) and 95% confidence intervals (CIs) were computed using a random effects model. From 14 papers and 25 ESs, the mean ES for contralateral repeated bout effect (CL-RBE) on 1-, 2-, and 3-day post maximal strength were -0.61 (95% CI = -0.80, -0.41), -0.50 (95% CI = -0.67, -0.33), and -0.74 (95% CI = -1.01, -0.48), respectively. For moderator analyses, the mean ESs were not influenced by type (isometric vs. isokinetic) of strength, but CL-RBE on maximal strength was influenced by duration (≤6 weeks) between bouts. Therefore, the meta-analysis demonstrated that an initial bout of exercise induces the protective effect on contralateral limb muscles regardless of the different type of strength, but can be affected by different duration (≤6 weeks) between exercise bouts.


Assuntos
Contração Isométrica , Mialgia , Humanos , Contração Isométrica/fisiologia , Músculo Esquelético/fisiologia , Exercício Físico/fisiologia , Contração Muscular/fisiologia
13.
Polymers (Basel) ; 14(22)2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36432977

RESUMO

In this study, the characteristics of a composite material composed of polypropylene (PP) and ultrahigh molecular weight polyethylene (UHMWPE) are investigated. The elastic properties of the PP/UHMWPE composite material composed of short UHMWPE fibers with a low aspect ratio and long UHMWPE fibers with a high aspect ratio are compared and analyzed. In addition, the elastic properties of the PP/UHMWPE composite materials are calculated via finite element analysis and the Halpin-Tsai model by changing the volume fraction of the UHMWPE fibers. The results show that when UHMWPE fibers with a low aspect ratio and volume fraction are used, the results of the modulus of elasticity based on the finite element analysis are consistent with those obtained using the Halpin-Tsai model, although the fiber volume fraction of the UHMWPE fibers increases. Meanwhile, the deviation between the results yielded by both methods increases with the aspect ratio of the fiber. In terms of the shear modulus, the Halpin-Tsai model shows a linear trend. The results from the finite element analysis differ significantly from those of the Halpin-Tsai model owing to the random orientation of the UHMWPE fibers inside the fiber. Using a contour graph constructed based on the finite element analysis results, the aspect ratio and volume fraction of the UHMWPE fibers can be inversely calculated based on the elastic properties when synthesizing a PP/UHMWPE fiber composite. In future studies, the interfacial bonding properties of UHMWPE fibers and PP should be compared and analyzed experimentally.

14.
Materials (Basel) ; 15(22)2022 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-36431493

RESUMO

This study uses the finite element method and numerical analysis to develop an eco-friendly composite material with shielding capabilities. A preliminary study was performed to predict the mechanical properties of the composite material. Polyethylene terephthalate and aluminum powder (AP) were selected as the matrix and enhancer, respectively. The particles of AP are spherical, with a diameter of 1 µm. Material properties were investigated as the AP volume fraction (VF) increased from 5-70%. The FEM results show that the physical properties for AP VFs improve by up to 40%, but there is no significant change in the elastic modulus, shear modulus, and Poisson's ratio at an AP VF of 50-70%. However, the numerical analysis models show that the elastic properties for AP VFs improve by up to 70%. The mechanical properties improved as the VF increased, and the FEM predicted values were reliable for VFs up to 40%. However, it was confirmed that 40% is the limit of AP VF in the FEM. In addition, the FEM and numerical analysis predictions showed that the most similar numerical analysis model was the Halpin-Tsai model. The predictions of the Halpin-Tsai model allowed prediction of the maximum VF above the FEM limit. If the correction coefficients of the FEM and numerical analysis models are derived based on the predictions of this study and future experimental results, reliable predictions can be obtained for the physical properties of composite materials.

15.
Curr Pharm Teach Learn ; 14(9): 1143-1153, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36154959

RESUMO

INTRODUCTION: The role of pharmacists is crucial in the care of individuals with HIV/AIDS. However, stigma in health care settings can be a deterrent to providing appropriate care. This paper assessed psychometric properties and convergent validity of the Health Care Provider HIV/AIDS Stigma Scale (HPASS) among pharmacy students in the United States (US) using Rasch analysis. METHODS: Students enrolled in four US universities were administered the survey (N = 203). Rasch analysis was conducted for each HPASS subscale (Stereotyping, Discrimination, and Prejudice) to assess dimensionality, model data fit, item difficulty, individual stigma, distribution of items and persons across item-person map, and rating scale function. Convergent validity evidence was established by comparing Pearson's correlation coefficients between HPASS subscales and the AIDS Attitude Scale (AAS) Avoidance subscale. RESULTS: Two items in the Prejudice subscale were misfit and therefore removed. The 6-point rating scale did not perform satisfactorily for HPASS subscales. Item difficulty ranges were wide [Stereotyping (-5 to 0.8 logits), Discrimination (-6 to 1 logits), Prejudice (-5 to 0.4 logits)]. Items were biased towards measuring higher levels of stigma. Person separation index was satisfactory (Stereotyping = 2.2; Discrimination = 2.06; Prejudice = 2.17) as was person separation reliability (Stereotyping = 0.83; Discrimination = 0.81; Prejudice = 0.83). Convergent validity was established by showing significant correlations between HPASS subscales and AAS Avoidance (P < .001). CONCLUSIONS: Modifying or removing misfit items of HPASS and exploring alternate rating scales for HPASS subscales will help better assess HIV/AIDS related stigma among pharmacy students.


Assuntos
Síndrome de Imunodeficiência Adquirida , Infecções por HIV , Pessoal de Saúde , Humanos , Psicometria , Reprodutibilidade dos Testes , Estados Unidos
16.
Bioprocess Biosyst Eng ; 45(10): 1731-1738, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36121507

RESUMO

Phycocyanin (PC) is a natural blue pigment that has great commercial value in food and pharmaceutical industry. Arthrospira (Spirulina) platensis is a photosynthetic spiral-shaped cyanobacterium containing a rich PC pigment. Autolysis is the enzymatic digestion of cells by the action of its own enzymes. To develop an effective and economical extraction process, an autolysis process was incorporated into the conventional freezing-thawing method. In the present study, 91% of maximal extraction yield of PC with 1.194 purity (A620/A280) was obtained via autolysis after 3 h of incubation at 37 °C without using an extraction salt solution or a successive freezing-thawing process. In addition to temperature, the initial concentration of bicarbonate in growth medium and the concentration of wet biomass are important parameters that influence the extraction yield of PC by autolysis.


Assuntos
Ficocianina , Spirulina , Bicarbonatos , Biomassa
17.
Molecules ; 27(18)2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-36144489

RESUMO

In this study, we calculated the elastic properties of polypropylene composites mixed with ultrahigh-molecular-weight polyethylene (UHMWPE) fibers. We applied micromechanics models that use numerical analysis, conducted finite element analysis using the homogenization method, and comparatively analyzed the characteristics of polypropylene (PP) containing UHMWPE fibers as reinforcement. The results demonstrate that elastic properties improved as the volume fraction of UHMWPE fiber increased. It was confirmed that the fibers had anisotropic elastic properties due to the shape of the fibers. In addition, it is necessary to compare these findings with future experimental results to obtain data for developing UHMWPE-PP composites.

18.
Cell Mol Life Sci ; 79(9): 505, 2022 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-36057892

RESUMO

In multiple cancers, autophagy promotes tumor development by recycling intracellular components into metabolic pathways. Autophagy-induced metabolic reprogramming and plasticity lead to cancer cell survival and resistance to anticancer therapy. We investigated the role of small leucine zipper protein (sLZIP) in autophagy and cell survival under nutrient-deficient conditions in colorectal cancer (CRC). sLZIP was induced by nutrient stress and increased the transcription of microtubule-associated protein 1A/1B-light chain 3 (LC3), by directly binding to its promoter. Under nutrient stress conditions, sLZIP activated autophagy and promoted the survival of CRC cells. sLZIP induced metabolic reprogramming of CRC cells, to activate glutaminolysis and the tricarboxylic acid cycle. sLZIP also enhanced the autophagic degradation of Keap1 and the nuclear accumulation of Nrf2, leading to NQO1 expression, for maintenance of redox homeostasis. sLZIP-knockout CRC cells exhibited impaired autophagy induction in the glycolytic inhibition state. Xenograft mice lacking sLZIP showed decreased tumor growth, by rendering CRC cells sensitive to glycolysis inhibition. The expression of sLZIP and LC3B was highly elevated in tumors of CRC patients compared to that in normal tissues, and correlated with the progression of CRC. These findings suggest that sLZIP drives autophagy and metabolic reprogramming to promote colorectal tumorigenesis.


Assuntos
Neoplasias Colorretais , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico , Animais , Autofagia , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Zíper de Leucina , Camundongos , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Nutrientes
19.
Artigo em Inglês | MEDLINE | ID: mdl-36142017

RESUMO

The role of physical activity in normal weight obesity (NWO), which is associated with increased cardiometabolic risk, is not clear. This study aimed to determine body composition phenotype-specific differences in objectively measured physical activity and sedentary time in adults in the United States. A total of 2055 adults with a body mass index (BMI) ≥ 18.5 m2 were studied using 2003-2006 National Health and Nutrition Examination Surveys. Physical activity and percent body fat (BF%) were measured using accelerometer and dual-energy X-ray absorptiometry, respectively. A BF% > 23.1% and >33.3% for men and women, respectively, was considered excess. A BMI of 18.5-24.9 kg/m2 with excess BF% was defined as NWO, while those with normal BF%, as normal weight lean (NWL). A BMI of ≥25 kg/m2 with excess BF% was considered overweight/obesity (OB). Compared to NWL, moderate to vigorous physical activity was significantly lower by 8.3 min (95% confidence interval/CI = -15.20, -1.40) and 10.18 min (95% CI = -14.83, -5.54) per day in NWO and OB, respectively. Low-intensity physical activity was also significantly lower by 17.71 min (95% CI = -30.61, -4.81) per day in NWO compared to NWL. However, sedentary time was not different. Objectively measured physical activity is significantly lower in NWO compared to NWL, while sedentary time is not.


Assuntos
Obesidade , Sobrepeso , Índice de Massa Corporal , Exercício Físico , Feminino , Humanos , Obesidade/diagnóstico , Obesidade/epidemiologia , Fatores de Risco , Estados Unidos/epidemiologia
20.
Materials (Basel) ; 15(15)2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35955382

RESUMO

This study proposes an electromagnetic shielding material sprayed with silver-coated copper powder (core-shell powder). The shielding properties of the material are analyzed in details section. Cross-sectional observation and sheet resistance measurement were used to determine the thickness and electrical conductivity of the electromagnetic shielding layer, which was generated by spray-coating; this aided in confirming the uniformity of the coating film. The results indicate that the electromagnetic interference shielding effectiveness increases when the silver-coated copper paste (core-shell paste) is used as the coating material rather than the conventional aluminum base. The proposed material can be used in various frequency ranges owing to the excellent shielding effectiveness of the core-shell paste used in this study. Further investigations on the optimized spray-coating type of electromagnetic shielding material are required based on the composition of the core-shell paste and the thickness of the coating film.

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