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1.
Heliyon ; 10(15): e34781, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39161841

RESUMO

Gasification is a thermochemical process that has gained significant interest in the field of biomass energy conversion. Despite the level of technological maturity of the process, the dynamic variation of the process as a result of changes in both the properties of the gasifying agent and biomass has not been analysed in sufficient depth. Therefore, the present study characterizes the process dynamically as a function of step-type changes in rice husk biomass moisture content and gasifying airflow. To identify stability conditions and the range for inducing disturbances, steady-state tests were carried out using a 32-factorial design. The experimental results demonstrate that within the tested range of airflow, the gasification process operates in the oxygen-limited zone. Despite increasing the airflow from 20 to 40 standard liters per minute (SLPM) and driving the reaction towards the combustion zone, the high temperatures achieved resulted in the gas reaching a peak Lower Heating Value (LHV) of 2.6 MJ/Nm3 and a gas power of 2.6 kW, with a Cold Gas Efficiency (CGE) of 62%. In contrast, the effect of biomass moisture content was negligible due to the thermal inertia of the reactor and the natural variation of the process. Dynamic evaluation revealed that the oxidation temperature and gas concentration were the variables that took the longest to return to stability after air disturbances. It took approximately 1200 s for the hydrogen (H2) concentration to stabilize, while the gas power required about 300 s. No clear results were observed regarding the impact of the dynamic disturbance in moisture content, which varied between 12.3% w.t and 21.5% w.t.

2.
Neotrop Entomol ; 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39141216

RESUMO

This study investigates the toxic effects of the insecticide spinetoram on the model organism Bombyx mori (Linnaeus) and explores the potential ameliorative properties of O-Vanillin. Sub-lethal concentrations of spinetoram were given to silkworm larvae via oral feed, resulting in reduced body weight, larval length, and impaired cocoon characteristics. A study of the enzymatic and non-enzymatic antioxidants revealed oxidative stress in the gut, fat body, and silk gland tissues, characterized by decreased antioxidants and increased lipid peroxidation. However, post-treatment with O-Vanillin effectively mitigated these toxic effects, preserving antioxidant capacities and preventing lipid peroxidation. Additionally, O-Vanillin prevented the loss of body weight and improved cocoon characteristics. At the histological level, spinetoram exposure caused mild histological damage in the gut, fat body, and silk gland. However, O-Vanillin post-treatment had ameliorative effects and mitigated the histological damages. To delve deeper into the mechanism of amelioration of O-Vanillin, in silico studies were used to study the interaction between an important xenobiotic metabolism protein of the Bombyx mori, i.e., Cytochrome p450, specifically CYP9A19, and O-Vanillin. We performed blind molecular docking followed by molecular dynamic simulation, and the results demonstrated stable binding interactions between O-Vanillin and CYP9A19, a cytochrome P450 protein in silkworm, belonging to the subfamily CYP9A, suggesting a potential role for O-vanillin in modulating xenobiotic metabolism.

3.
Psychiatry Res Neuroimaging ; 344: 111861, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39153230

RESUMO

Understanding the neurophysiological mechanisms of schizophrenia (SZ) is one of the challenges of neuroscience. Many anatomical and functional studies have pointed to problems in brain connectivity in SZ individuals. However, little is known about the relationships between specific brain regions and impairments in brain connectivity in SZ individuals. Herein we propose a new approach using time-varying graphs and the motif synchronization method to build dynamic brain functional networks (BFNs). Dynamic BFNs were constructed from resting-state electroencephalography (rs-EEG) of 14 schizophrenia (SZ) individuals and 14 healthy controls (HCs). BFNs were evaluated based on the percentage of synchronization importance between a pair of regions (considering external and internal interactions) over time. We found differences in the directed interaction between brain regions in SZ individuals compared to the control group. Our method revealed low bilaterally directed interactions between the temporal lobes in SZ individuals compared to HCs, indicating a potential link between altered brain connectivity and the characteristic symptoms of schizophrenia. From a clinical perspective, these results shed light on developing new therapeutic approaches targeting these specific neural interactions that are altered in individuals with SZ. This knowledge allows the application of better interventions focused on restoring or compensating for interrupted connectivity patterns.


Assuntos
Encéfalo , Eletroencefalografia , Esquizofrenia , Humanos , Esquizofrenia/fisiopatologia , Esquizofrenia/diagnóstico por imagem , Eletroencefalografia/métodos , Adulto , Masculino , Feminino , Encéfalo/fisiopatologia , Encéfalo/diagnóstico por imagem , Descanso/fisiologia , Rede Nervosa/fisiopatologia , Rede Nervosa/diagnóstico por imagem , Adulto Jovem , Pessoa de Meia-Idade
4.
Dermatol Ther (Heidelb) ; 14(8): 2093-2108, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38954382

RESUMO

INTRODUCTION: IncobotulinumtoxinA (Xeomin®) is used in the treatment of dynamic wrinkles and the aesthetic repositioning of facial structures. The duration of its muscular effect typically extends for around 4 months. However, the residual aesthetic benefit can be observed for a longer period. To date, the long-term aesthetic benefit of incobotulinumtoxinA in facial aesthetics has not been systematically evaluated. This study aimed to evaluate longitudinally the duration and aesthetic benefits of incobotulinumtoxinA in the treatment of the upper face in adult women. METHODS: A quasi-experimental, evaluator-blind, clinical trial involving 28 adult women (30-60 years old) with facial movement lines, undergoing treatment of the upper face with incobotulinumtoxinA by two injectors, following an individualized protocol (ONE21 and glabellar contraction patterns) was performed. Participants were evaluated on the day of the intervention (day 0) and days 30, 120, 180, and 240, and subjected to standardized photographs. The following outcomes were evaluated blindly at each visit: Merz Aesthetics Facial Contraction Scale (MAS), GAIS (Global Aesthetic Improvement Scale), and patient satisfaction. Adverse effects were evaluated at each visit. RESULTS: Participants ranged in age from 30 to 60 years, 93% were self-declared white, and most of their baseline MAS scores for dynamic lines were moderate and severe. All the parameters presented significative reduction from baseline until day 180. At day 240, the dynamic MAS scores were lower than baseline for forehead lines in 15.4% (95% confidence interval (CI) 0.8-30.0%) of the participants, for glabellar lines in 38.5% (95% CI 18.8-58.1%), and for crow's feet lines in 26.9% (95% CI 9.0-44.8%). Aesthetic improvement compared to baseline was identified in 35% (CI 95% 23‒50%) of the participants at day 240, and 62% (CI 95% 42‒81%) of the sample kept reporting some satisfaction with the procedure. CONCLUSION: The aesthetic treatment of the upper face with incobotulinumtoxinA demonstrates enduring clinical benefits, and patient satisfaction lasting up to 180 days in most participants. The length of efficacy, which exceeded those reported in the literature, may be attributed to the use of techniques based on individualized assessment such as ONE21 and glabellar patterns of contraction.

5.
Surg Radiol Anat ; 46(9): 1447-1454, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39043949

RESUMO

PURPOSE: Depending on its axis, pronation varies from the radius rotation around the steady ulna to the reciprocal adduction of the radius and abduction of the ulna. While there is no question that pronator teres is a central pronation agonist, anconeus's role is not settled. The current investigation comparing palpation and ultrasonography in these two muscles during pronation along the axis capitulum-second digit evolved from a serendipitous finding in a clinical anatomy seminar. METHODS: Single-hand palpation and two-transducer ultrasonography over anconeus and pronator teres were used on ten normal subjects to investigate their contraction during pronation around the capitulum-second digit axis. These studies were done independently and blind to the results of the other. The statistical analysis between palpation and ultrasonography was performed with Cohen's kappa coefficient and the χ2 test. RESULTS: On palpation, on resisted full pronation, anconeus contracted in 8/10 subjects and pronator teres in 10/10 subjects. Without resistance, the corresponding ratios were 5/10 and 9/10. On two-transducer ultrasonography, the comparable ratios were 7/10 and 10/10, and 3/10 and 10/10. A fair concordance (Cohen's kappa = 0.21) between palpation and ultrasonography in detecting the simultaneous status of anconeus and pronator teres during resisted full pronation. Anatomic dissection illustrated the elements involved. CONCLUSIONS: Plain palpation confirmed by ultrasonography showed the simultaneous contraction of anconeus and pronator teres during resisted pronation in most of the studied subjects. The study suggests that palpation can be helpful in directly studying muscle activity during movement.


Assuntos
Voluntários Saudáveis , Músculo Esquelético , Palpação , Pronação , Ultrassonografia , Humanos , Pronação/fisiologia , Ultrassonografia/métodos , Masculino , Adulto , Feminino , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/fisiologia , Músculo Esquelético/anatomia & histologia , Palpação/métodos , Adulto Jovem , Contração Muscular/fisiologia
6.
Polymers (Basel) ; 16(14)2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-39065286

RESUMO

Hyaline cartilage is a highly specialized tissue. When injured, its repair capacity is low, which results in the massive destruction of the articular surface. Using tissue engineering and genetic engineering techniques, it is possible to provide a suitable microenvironment providing chondrocyte growth factors involved in the development of hyaline cartilage proteins, as well as cell proliferation and differentiation. Our aim was to stimulate the synthesis of an extracellular matrix via the chondrocytes included in a fibrin matrix through the addition or overexpression of IGF1 and/or FGF2, while maintaining a constant agitation of the culture medium. Collagen type II and glycosaminoglycans increased during the entire incubation time. In contrast, collagen type I decreased its expression under the same culture conditions, transfecting or supplementing growth factors to chondrocytes. However, chondrocytes that were not transfected or supplemented showed a general increase in the proteins analyzed in this study. The presence of IGF1 and FGF2 increased the protein synthesis of the hyaline cartilage, regardless of which one was the source of growth factors. Continuous agitation using the spinner flask allows for the adequate nutrition of chondrocytes included in the fibrin matrix. However, they require growth factors to up-regulate or down-regulate collagenous proteins.

7.
Sci Rep ; 14(1): 15498, 2024 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-38969829

RESUMO

Black liquor (BL) is the major bioproduct and biomass fuel in pulp mill processes. However, the high viscosity of BL makes it a challenging material to work with, resulting in issues with evaporators and heat exchangers during its transport and processing. The thermal and rheological properties of BLs from Pinus sp. (PBL) and Eucalyptus sp. (EBL) were studied. FTIR spectra revealed the presence of the characteristic functional groups and the chemical composition in liquors. TGA/DTG curves showed three characteristic degradation stages related to evaporation of water, pyrolysis of organic groups, and condensation of char. Rheologically, liquors are classified as non-Newtonian and with comportment pseudoplastic. Their rheological dynamic shear properties included a linear viscoelastic region up to 1% shear strain, while frequency sweeps showed that storage modulus (G') > loss modulus (G''), thus confirming the solid-like behavior of both BLs. The rheological study demonstrated that increasing the temperature and oscillatory deformations of PBL and EBL decreased their degree of viscoelasticity, which could favor their pumping and handling within the pulp mill, as well as the droplet formation and swelling characteristics in the recovery furnace.


Assuntos
Eucalyptus , Pinus , Reologia , Eucalyptus/química , Pinus/química , Viscosidade , Brasil , Finlândia , Temperatura , Espectroscopia de Infravermelho com Transformada de Fourier
8.
Polymers (Basel) ; 16(13)2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-39000808

RESUMO

This work proposes for the first time protecting-reflecting on both sides of plated mirrors and a solution to polycarbonate surface vulnerability to weathering and scratching using tungsten disulfide (WS2) by mechanical polishing. The ability of the dynamic chemical plating (DCP) technique to deposit Ag films at the nanometer scale on a polycarbonate (PC) substrate and its characteristics to be metallized is also shown. These deposits hold significant promise for concentrated solar power (CSP) applications. Complementarily, the application of WS2 as a reflective film for CSP by mechanical polishing on smooth polycarbonate surfaces is both novel and practical. This technique is innovative and scalable without needing reactants or electrical potential, making it highly applicable in real-world scenarios, including, potentially, on-site maintenance. The effects of surface morphology and adhesion, and the reflectivity parameters of the silver metallic surfaces were investigated. Wettability was investigated because it is important for polymeric surfaces in the activation and metal deposition immediately after redox reactions. The flame technique improved wettability by modifying the surface with carbonyl and carboxyl functional groups, with PC among the few industrial polymers that resisted such a part of the process. The change in the chemical composition, roughness, and wettability of the surfaces effectively improved the adhesion between the Ag film and the PC substrate. However, it did not significantly affect the adhesion between PC and WS2 and showed its possible implementation as a first surface mirror. Overall, this work provides a scalable, innovative method for improving the durability and reflectivity of polycarbonate-based mirrors, with significant implications for CSP applications.

9.
Brain Topogr ; 37(6): 1043-1054, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38839695

RESUMO

Semantic verbal fluency (SVF) impairment is present in several neurological disorders. Although activation in SVF-related areas has been reported, how these regions are connected and their functional roles in the network remain divergent. We assessed SVF static and dynamic functional connectivity (FC) and effective connectivity in healthy participants using functional magnetic resonance imaging. We observed activation in the inferior frontal (IFG), middle temporal (pMTG) and angular gyri (AG), anterior cingulate (AC), insular cortex, and regions of the superior, middle, and medial frontal gyri (SFG, MFG, MidFG). Our static FC analysis showed a highly interconnected task and resting state network. Increased connectivity of AC with the pMTG and AG was observed for the task. The dynamic FC analysis provided circuits with connections similarly modulated across time and regions related to category identification, language comprehension, word selection and recovery, word generation, inhibition of speaking, speech planning, and articulatory planning of orofacial movements. Finally, the effective connectivity analysis provided a network that best explained our data, starting at the AG and going to the pMTG, from which there was a division between the ventral and dorsal streams. The SFG and MFG regions were connected and modulated by the MidFG, while the inferior regions formed the ventral stream. Therefore, we successfully assessed the SVF network, exploring regions associated with the entire processing, from category identification to word generation. The methodological approach can be helpful for further investigation of the SVF network in neurological disorders.


Assuntos
Mapeamento Encefálico , Encéfalo , Imageamento por Ressonância Magnética , Vias Neurais , Semântica , Humanos , Masculino , Feminino , Imageamento por Ressonância Magnética/métodos , Adulto , Mapeamento Encefálico/métodos , Vias Neurais/fisiologia , Vias Neurais/diagnóstico por imagem , Adulto Jovem , Encéfalo/fisiologia , Encéfalo/diagnóstico por imagem , Comportamento Verbal/fisiologia , Fala/fisiologia , Rede Nervosa/fisiologia , Rede Nervosa/diagnóstico por imagem
10.
Protein Sci ; 33(7): e5064, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38864722

RESUMO

Due to the low temperature, the Antarctic marine environment is challenging for protein functioning. Cold-adapted organisms have evolved proteins endowed with higher flexibility and lower stability in comparison to their thermophilic homologs, resulting in enhanced reaction rates at low temperatures. The Antarctic bacterium Pseudoalteromonas haloplanktis TAC125 (PhTAC125) genome is one of the few examples of coexistence of multiple hemoglobin genes encoding, among others, two constitutively transcribed 2/2 hemoglobins (2/2Hbs), also named truncated Hbs (TrHbs), belonging to the Group II (or O), annotated as PSHAa0030 and PSHAa2217. In this work, we describe the ligand binding kinetics and their interrelationship with the dynamical properties of globin Ph-2/2HbO-2217 by combining experimental and computational approaches and implementing a new computational method to retrieve information from molecular dynamic trajectories. We show that our approach allows us to identify docking sites within the protein matrix that are potentially able to transiently accommodate ligands and migration pathways connecting them. Consistently with ligand rebinding studies, our modeling suggests that the distal heme pocket is connected to the solvent through a low energy barrier, while inner cavities play only a minor role in modulating rebinding kinetics.


Assuntos
Proteínas de Bactérias , Pseudoalteromonas , Hemoglobinas Truncadas , Pseudoalteromonas/metabolismo , Pseudoalteromonas/genética , Pseudoalteromonas/química , Cinética , Hemoglobinas Truncadas/química , Hemoglobinas Truncadas/metabolismo , Hemoglobinas Truncadas/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Simulação de Dinâmica Molecular , Regiões Antárticas , Ligantes
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