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1.
Artigo em Inglês | MEDLINE | ID: mdl-38776481

RESUMO

2D/2D step-scheme (S-scheme) piezo-photocatalysts for the production of fine chemicals, such as hydrogen peroxide (H2O2), have attracted significant attention of global scientists owing to the efficiency in utilizing surface piezoelectric effects from 2D materials to overcome rapid charge recombination in photocatalytic processes. In this research, we reported the fabrication of 2D S-doped VOx deposited on 2D g-C3N4 to produce H2O2 via the piezo-photocatalytic process with high production yields at 20.19 mmol g-1 h-1, which was 1.75 and 4.87 times higher than that from solely piezo-catalytic and photocatalytic H2O2 generation. The finding pointed out that adding sulfur (S) to VOx can help to improve the catalytic outcomes by modifying the electronic properties of pristine VOx. In addition, when coupled with g-C3N4, the presence of S limits the formation of graphene in the VOx/g-C3N4 composites, causing shielding effects and pushing the cascade reactions toward water generation in the materials. Besides, the research also sheds light on the charge transport between g-C3N4 and S-VOx under irradiation and how the composites work to trigger the formation of H2O2. The presence of S in the composite systems enhances charge transfer between two semiconductors by strengthening the internal electric fields (IEF) to drive electrons moving in one direction, as demonstrated by density functional theory (DFT) calculations. Moreover, the formation of H2O2 significantly relies on the reduction of oxygen to generate oxygenic radical species at the g-C3N4 sites. Meanwhile, S-VOx provides oxidative sites in the composites to oxidize water molecules to directly or indirectly generate H2O2 or O2, which will further participate in the reactions to produce the final products. This study confirms the validation of S-scheme piezo-photocatalysts, thus encouraging further research on developing heterojunction materials with high catalytic efficiency, which can be used in practical conditions.

2.
Biochim Biophys Acta Rev Cancer ; : 189112, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38761983

RESUMO

The field of bacteria-based cancer therapy, which focuses on the key role played by the prevalence of bacteria, specifically in tumors, in controlling potential targets for cancer therapy, has grown enormously over the past few decades. In this review, we discuss, for the first time, the global cancer situation and the timeline for using bacteria in cancer therapy. We also explore how interdisciplinary collaboration has contributed to the evolution of bacteria-based cancer therapies. Additionally, we address the challenges that need to be overcome for bacteria-based cancer therapy to be accepted in clinical trials and the latest advancements in the field. The groundbreaking technologies developed through bacteria-based cancer therapy have opened up new therapeutic strategies for a wide range of therapeutics in cancer.

3.
Chem Biodivers ; : e202400438, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38581153

RESUMO

A bio-guided isolation was applied to the Vietnamese lichen Roccella montagnei based on alpha-glucosidase inhibition. Six compounds were isolated and structurally elucidated, including a new ortho depside, montagneside A (1), together with five known compounds, sekikaic acid (2), lanost-7-en-3ß-ol (3), ethyl orsellinate (4), D-montagnetol (5), and D-erythrin (6). Their chemical structures were identified by extensive 1D and 2D NMR analysis, high-resolution mass spectroscopy, and comparisons with those reported in the literature. D-Erythrin (6), a major component, was selected for further modification using Smiles rearrangement. Three erythritol derivatives 6a-6c were synthesized. Compounds 1-3, 6, and 6a-6c were evaluated for alpha-glucosidase inhibition. Compounds 2 and 6a-6c showed significant alpha-glucosidase inhibition with IC50 values ranging from 7.9 to 149 µM, respectively. Molecular docking was applied to the most active compound 6a to clarify the inhibitory mechanism.

4.
J Ethnopharmacol ; 330: 118226, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-38670401

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Idiopathic pulmonary fibrosis (IPF) is a progressive fibrosing pulmonary disorder that has a poor prognosis and high mortality. Although there has been extensive effort to introduce several new anti-fibrotic agents in the past decade, IPF remains an incurable disease. Mimosa pudica L., an indigenous Vietnamese plant, has been empirically used to treat respiratory disorders. Nevertheless, the therapeutic effects of M. pudica (MP) on lung fibrosis and the mechanisms underlying those effects remain unclear. AIM OF THE STUDY: This study investigated the protective effect of a crude ethanol extract of the above-ground parts of MP against pulmonary fibrogenesis. MATERIALS AND METHODS: Inflammatory responses triggered by TNFα in structural lung cells were examined in normal human lung fibroblasts and A549 alveolar epithelial cells using Western blot analysis, reverse transcription-quantitative polymerase chain reaction assays, and immunocytochemistry. The epithelial-to-mesenchymal transition (EMT) was examined via cell morphology observations, F-actin fluorescent staining, gene and protein expression measurements, and a wound-healing assay. Anti-fibrotic assays including collagen release, differentiation, and measurements of fibrosis-related gene and protein expression levels were performed on TGFß-stimulated human lung fibroblasts and lung fibroblasts derived from mice with fibrotic lungs. Finally, in vitro anti-fibrotic activities were validated using a mouse model of bleomycin-induced pulmonary fibrosis. RESULTS: MP alleviated the inflammatory responses of A549 alveolar epithelial cells and lung fibroblasts, as revealed by inhibition of TNFα-induced chemotactic cytokine and chemokine expression, along with inactivation of the MAPK and NFκB signalling pathways. MP also partially reversed the TGFß-promoted EMT via downregulation of mesenchymal markers in A549 cells. Importantly, MP decreased the expression levels of fibrosis-related genes/proteins including collagen I, fibronectin, and αSMA; moreover, it suppressed collagen secretion and prevented myofibroblast differentiation in lung fibroblasts. These effects were mediated by FOXO3 stabilization through suppression of TGFß-induced ERK1/2 phosphorylation. MP consistently protected mice from the onset and progression of bleomycin-induced pulmonary fibrosis. CONCLUSION: This study explored the multifaceted roles of MP in counteracting the pathobiological processes of lung fibrosis. The results suggest that further evaluation of MP could yield candidate therapies for IPF.


Assuntos
Transição Epitelial-Mesenquimal , Proteína Forkhead Box O3 , Sistema de Sinalização das MAP Quinases , Camundongos Endogâmicos C57BL , Extratos Vegetais , Fibrose Pulmonar , Animais , Humanos , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Células A549 , Camundongos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/induzido quimicamente , Proteína Forkhead Box O3/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Masculino , Bleomicina , Antifibróticos/farmacologia , Pulmão/efeitos dos fármacos , Pulmão/patologia , Pulmão/metabolismo , Fibrose Pulmonar Idiopática/tratamento farmacológico , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/patologia
5.
Carbohydr Polym ; 334: 122016, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38553203

RESUMO

This paper reports an environment-friendly biobased foam made with cellulose nanofiber (CNF) and a biobased hyperbranched crosslinker, glycerol succinic anhydride (GSA). As a biobased hyperbranched crosslinker, carboxyl-terminated GSA is synthesized through a straightforward esterification process involving glycerol and succinic anhydride. The GSA-crosslinked CNF (GSA/CNF) foam is prepared using a facile, sustainable, cost-effective, and efficient solvent-exchange method. The resulting foam exhibits notable characteristics, including improved dimensional stability, remarkably low density (13.41 mg/cm3) with high porosity (>99 %), and exceptional compressive strength (494 kPa) and modulus (452 kPa). Further, the foam offers outstanding sound absorption capabilities with a coefficient of 0.986 at 2 kHz and remarkably low thermal conductivity (30.18 mW/mK), significantly lower than commonly used and reported porous materials, indicating its potential as an efficient, environmentally friendly sound absorption and thermal insulation material.

6.
Sci Rep ; 14(1): 5593, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38454029

RESUMO

Expanding upon the well-established Takagi-Sugeno (T-S) fuzzy model, the T-S fuzzy descriptor model emerges as a robust and flexible framework. This article introduces the development of optimal and robust-optimal controllers grounded in the principles of stability control and fuzzy descriptor systems. By transforming complicated inequalities into linear matrix inequalities (LMI), we establish the essential conditions for controller construction, as delineated in theorems. To substantiate the utility of these controllers, we employ the rotary inverted pendulum as a testbed. Through diverse simulation scenarios, these controllers, rooted in fuzzy descriptor systems, demonstrate their practicality and effectiveness in ensuring the stable control of inverted pendulum systems, even in the presence of uncertainties within the model. This study highlights the adaptability and robustness of fuzzy descriptor-based controllers, paving the way for advanced control strategies in complex and uncertain environments.

7.
Artigo em Inglês | MEDLINE | ID: mdl-38367698

RESUMO

OBJECTIVES: The HeartMate 3 (Abbott) left ventricular assist device provides substantial improvement in long-term morbidity and mortality in patients with advanced heart failure. The Implantation of the HeartMate 3 in Subjects With Heart Failure Using Surgical Techniques Other Than Full Median Sternotomy study compares thoracotomy-based implantation clinical outcomes with standard median sternotomy. METHODS: We conducted a prospective, multicenter, single-arm study in patients eligible for HeartMate 3 implantation with thoracotomy-based surgical technique (bilateral thoracotomy or partial upper sternotomy with left thoracotomy). The composite primary end point was survival free of disabling stroke (modified Rankin score >3), or reoperation to remove or replace a malfunctioning device, or conversion to median sternotomy at 6-months postimplant (elective transplants were treated as a success). The primary end point (noninferiority, -15% margin) was assessed with >90% power compared with a propensity score-matched cohort (ratio 1:2) derived from the Multi-Center Study of MagLev Technology in Patients Undergoing Mechanical Circulatory Support Therapy With HeartMate 3 continued access protocol. RESULTS: The study enrolled 102 patients between December 2020 and July 2022 in the thoracotomy-based arm at 23 North American centers. Follow-up concluded in December 2022. In the Implantation of the HeartMate 3 in Subjects With Heart Failure Using Surgical Techniques Other Than Full Median Sternotomy study group, noninferiority criteria was met (absolute between-group difference, -1.2%; Farrington Manning lower 1-sided 95% CI, -9.3%; P < .0025) and event-free survival was not different (85.0% vs 86.2%; hazard ratio, 1.01; 95% CI, 0.58-2.10). Length of stay with thoracotomy-based implant was longer (median, 20 vs 17 days; P = .03). No differences were observed for blood product utilization, adverse events (including right heart failure), functional status, and quality of life between cohorts. CONCLUSIONS: Thoracotomy-based implantation of the HeartMate 3 left ventricular assist device is noninferior to implantation via standard full sternotomy. This study supports thoracotomy-based implantation as an additional standard for surgical implantation of the HeartMate 3 left ventricular assist device.

8.
Heliyon ; 10(3): e25272, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38327421

RESUMO

With the increased demand for biobased epoxy thermosets as an alternative to petroleum-based materials in various fields, developing environment-friendly and high-performance natural fiber-biobased epoxy nanocomposites is crucial for industrial applications. Herein, an environment-friendly nanocomposite is reported by introducing cellulose nanofiber (CNF) in situ interaction with lignin-derived vanillin epoxy (VE) monomer and 4, 4´-diaminodiphenyl methane (DDM) hardener that serves as a multifunctional platform. The CNF-VE nanocomposite is fabricated by simply dispersing the CNF suspension to the VE and DDM hardener solution through the in-situ reaction, and its mechanical properties and thermal insulation behavior, wettability, chemical resistance, and optical properties are evaluated with the CNF weight percent variation. The well-dispersed CNF-VE nanocomposite exhibited high tensile strength (∼127.78 ± 3.99 MPa) and strain-at-break (∼16.49 ± 0.61 %), haziness (∼50 %) and UV-shielding properties. The in situ loading of CNF forms covalent crosslinking with the VE and favors improving the mechanical properties along with the homogeneous dispersion of CNF. The CNF-VE nanocomposite also shows lower thermal conductivity (0.26 Wm-1K-1) than glass. The environment-friendly and high-performance nanocomposite provides multiple platforms and can be used for building materials.

9.
R Soc Open Sci ; 11(1): 230872, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38298397

RESUMO

It is well accepted that remanufacturing, the returning of a product that has reached the end of its service life to its original condition, is economically and environmentally beneficial. Robotizing disassembly can make remanufacturing even more cost-effective by removing a substantial proportion of the labour costs associated with dismantling end-of-life products for subsequent processing. As unplugging of press-fitted components is a common operation in disassembly, it is appropriate to investigate how it can be robotized. This paper discusses an unplugging technique, twist-and-pull or twisting-pulling, to reduce the axial frictional resistance during the unplugging process and enable a robot to perform it easily. Through theoretical modelling, simulations, and experimental analysis, the paper explores the interaction between twisting, pulling and axial friction reduction during unplugging. Analysis of the experimental, simulation and theoretical results has confirmed that for a small radial interference, twist-and-pull reduces the axial friction and the maximum required unplugging force.

10.
J Surg Res ; 296: 772-780, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38382156

RESUMO

INTRODUCTION: We examined the association of socioeconomic status as defined by median household income quartile (MHIQ) with mortality and readmission patterns following open repair of acute type A aortic dissection (ATAAD) in a nationally representative registry. METHODS: Adults who underwent open repair of ATAAD were selected using the US Nationwide Readmissions Database and stratified by MHIQ. Patients were selected based on diagnostic and procedural codes. The primary endpoint was 30-d readmission. RESULTS: Between 2016 and 2019, 10,288 individuals (65% male) underwent open repair for ATAAD. Individuals in the lowest income quartile were younger (median: 60 versus 64, P < 0.05) but had greater Elixhauser comorbidity burden (5.9 versus 5.7, P < 0.05). Across all groups, in-hospital mortality was approximately 15% (P = 0.35). On multivariable analysis adjusting for baseline comorbidity burden, low socioeconomic status was associated with increased readmission at 90 d, but not at 30 d. Concomitant renal disease (odds ratio [OR], 1.68; P < 0.001), pulmonary disease (OR, 1.26; P < 0.001), liver failure (OR 1.2, P = 0.04), and heart failure (OR, 1.17; P < 0.001) were all associated with readmission at 90 d. The primary indication for readmission was most commonly cardiac (33%), infectious (16.5%), and respiratory (9%). CONCLUSIONS: In patients who undergo surgery for ATAAD, lower MHIQ was associated with higher odds of readmission following open repair. While early readmission for individuals living in the lowest income communities is likely attributable to greater baseline comorbidity burden, we observed that 90-d readmission rates are associated with lower MHIQ regardless of comorbidity burden. Further investigation is required to determine which patient-level and system-level interventions are needed to reduce readmissions in the immediate postoperative period for resource poor areas.


Assuntos
Dissecção Aórtica , Readmissão do Paciente , Adulto , Humanos , Masculino , Feminino , Fatores de Risco , Comorbidade , Classe Social , Dissecção Aórtica/epidemiologia , Dissecção Aórtica/cirurgia , Estudos Retrospectivos
11.
Clin Transplant ; 38(1): e15239, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38289889

RESUMO

Infection and rejection outcomes were retrospectively analyzed in patients following liver transplant and separately following heart transplant with patients being stratified by their severity of immediate postoperative insulin resistance as measured by the peak insulin drip rate that was required to reduce glucose levels. For each group, these peak insulin drip rates were divided into quartiles (Q). In liver transplant patients (n = 207), those in Q4 (highest infusion rate) had significantly fewer infections up to 6 months post-transplant (42.3% vs. 60.0%, p = .036) and borderline fewer rejection episodes (25.0% vs. 40.0%, p = .066) compared to Q1-Q3 patients. To confirm these unexpected results, a subsequent similar analysis in heart transplant (n = 188) patients again showed that Q4 patients had significantly fewer infections up to 6 months (19.1% vs. 53.9%, p < .0001) compared to Q1-Q3 patients. Logistic regression in a subset of 103 cardiac transplant patients showed that the maximum glucose during surgery, prior MI, and hypertension were associated with severe insulin resistance (SIR) status, while the presence of pre-existing diabetes and BMI were not. We hypothesize that patients are who are able to mount a more robust counter-regulatory response that causes the insulin resistance may be healthier and thus able to mount a better response to infections.


Assuntos
Transplante de Coração , Resistência à Insulina , Insulinas , Humanos , Estudos Retrospectivos , Transplante de Coração/efeitos adversos , Glucose , Insulina/uso terapêutico
12.
Ann Thorac Surg ; 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38286202

RESUMO

BACKGROUND: The management of aortic stenosis has evolved to stratification by age as reflected in recent societal guidelines. We evaluated age-stratified surgical aortic valve replacement (SAVR) trends and outcomes in patients with bicuspid aortic valve (BAV) or tricuspid aortic valve (TAV) from The Society of Thoracic Surgeons Adult Cardiac Surgery Database. METHODS: This cohort included adults (≥18 years) undergoing SAVR for severe aortic stenosis between July 2011 and December 2022. Comparisons were stratified by age (<65 years, 65-79 years, ≥80 years) and BAV or TAV status. Primary end points included operative mortality, composite morbidity and mortality, and permanent stroke. Observed to expected ratios by The Society of Thoracic Surgeons predicted risk of mortality were calculated. RESULTS: In total, 200,849 SAVR patients (55,326 BAV [27.5%], 145,526 TAV [72.5%]) from 1238 participating hospitals met study criteria. Annual SAVR volumes decreased by 45% (19,560 to 10,851) during the study period. The decrease was greatest (96%) for patients ≥80 years of age (4914 to 207). The relative prevalence of BAV was greater in younger patients (<65 years, 69,068 [49.5% BAV]; 65-79 years, 104,382 [19.1% BAV]; ≥80 years, 27,399 [4.5% BAV]). The observed mortality in <80-year-old BAV patients (<65 years, 1.08; 65-79 years, 1.21; ≥80 years, 3.68) was better than the expected mortality rate (<65 years, 1.22; 65-79 years, 1.54; ≥80 years, 3.14). CONCLUSIONS: SAVR volume in the transcatheter era has decreased substantially, particularly for patients ≥80 years old and for those with TAV. Younger patients with BAV have better than expected outcomes, which should be carefully considered during shared decision-making in the treatment of aortic stenosis. SAVR should remain the preferred therapy in this population.

13.
PLoS One ; 19(1): e0295898, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38206956

RESUMO

The Asia-Pacific region is recognised as an epicentre of emerging infectious diseases (EIDs), of which 75% are zoonotic in nature. Vietnam is recognised as a potential hotspot for zoonotic EIDs. There is a growing recognition that progress towards global health security requires greater focus on collaboration between the human health and animal health sectors to control diseases at their animal source and prevent against human health impacts. Assessment of veterinary epidemiology capacity in Vietnam is paramount to strengthening the health security of Asia-Pacific. This study aims to evaluate the national capacity and needs of veterinary services in Vietnam in biosecurity, biosafety and One Health. A cross-sectional, convergent mixed-methods study was conducted between November 2020 and April 2021. An online questionnaire was administered to government-employed field veterinarians. Descriptive analyses and logistic regression models were performed using survey responses to understand capacity in the field. Semi-structured interviews were also conducted with stakeholders in veterinary services including government, academia, research institutes, non-profit and international organisations. Coding and thematic analysis using a deductive approach was used for data collected from interviews to contextualise findings from the survey and understand institutional capacity. In total, 178 field veterinarians completed the online survey and 25 stakeholders were interviewed. The majority of participants had reported receiving training in biosecurity and biosafety, including use of personal protective equipment. Most respondents reported practicing good biosecurity measures (92%) and good biosafety measures (88%). Physical and socioeconomic barriers to practicing biosecurity were reported to be prevalent for smallholder farmers, which may suggest a gap in the capacity of veterinary services to provide cost-effective and practical biosecurity strategies. Seventy five percent of participants had never or rarely participated in One Health approaches in the field in the last 12 months and 69% reported further training as a high priority. There was a knowledge gap reported amongst district and commune-level veterinary staff about the need for, and awareness of multisectoral collaboration. Respondents that completed postgraduate qualifications in epidemiology or Field Epidemiology Training Programs (adjusted OR: 3.06; 95% CI: 1.01, 9.23, p = 0.046) and had longer job tenure between 10-12 years (OR: 10.38; 95% CI: 3.06, 35.15, p = <0.001) were more likely to have higher levels of experience in One Health. This study identified gaps in knowledge, attitudes and adoption of practices related to biosecurity, biosafety and One Health specifically in lower-level or less experienced veterinary staff without further training opportunities in epidemiology. These findings enable prioritisation of training, policy, and planning activities to further enhance the national capacity of veterinary services in Vietnam.


Assuntos
Doenças Transmissíveis Emergentes , Saúde Única , Animais , Humanos , Biosseguridade , Contenção de Riscos Biológicos , Avaliação das Necessidades , Vietnã , Estudos Transversais , Inquéritos e Questionários
14.
Acta Pharm Sin B ; 14(1): 273-291, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38261813

RESUMO

Obesity has been known to negatively modulate the life-span and immunosuppressive potential of mesenchymal stromal cells (MSC). However, it remains unclear what drives the compromised potency of obese MSC. In this study, we examined the involvement of adiponectin, an adipose tissue-derived hormone, in obesity-induced impaired therapeutic function of MSC. Diet-induced obesity leads to a decrease in serum adiponectin, accompanied by impairment of survival and immunomodulatory effects of adipose-derived MSC (ADSC). Interestingly, priming with globular adiponectin (gAcrp) improved the immunomodulatory potential of obese ADSC. Similar effects were also observed in lean ADSC. In addition, gAcrp potentiated the therapeutic effectiveness of ADSC in a mouse model of DSS-induced colitis. Mechanistically, while obesity inhibited the glycolytic capacity of MSC, gAcrp treatment induced a metabolic shift toward glycolysis through activation of adiponectin receptor type 1/p38 MAPK/hypoxia inducible factor-1α axis. These findings suggest that activation of adiponectin signaling is a promising strategy for enhancing the therapeutic efficacy of MSC against immune-mediated disorders.

15.
ACS Omega ; 9(2): 3017-3027, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38250344

RESUMO

This study examines the role of water in binding equilibria with a special focus on secondary solutes (cosolutes) that influence the equilibrium but are not constituents of the final product. Using a thermodynamic framework that includes an explicit term for the release of water molecules upon binding, this investigation reveals how solutes may alter equilibria by changing the activity of the reactants, reflected in ΔG°(obs), and by changing the chemical potential of the solvent, reflected in ΔGS. The framework is applied to four experimental binding systems that differ in the degree of electrostatic contributions. The model systems include the chelation of Ca2+ by EDTA and three host-guest reactions; the pairings of p-sulfonatocalix[4]arene with tetramethylammonium ion, cucurbit[7]uril with N-acetyl-phenylalanine-amide, and ß-cyclodextrin with adamantane carboxylate are tested. Each reaction pair is examined by isothermal titration calorimetry at 25 °C in the presence of a common osmolyte, sucrose, and a common chaotrope, urea. Molar solutions of trehalose and phosphate were also tested with selected models. In general, cosolutes that enhance binding tend to reduce the solvation free energy penalty and cosolutes that weaken binding tend to increase the solvation free energy penalty. Notably, the nonpolar-nonpolar interaction between adamantane carboxylate and ß-cyclodextrin is characterized by a ΔGS value near zero. The results with ß-cyclodextrin, in particular, prompt further discussions of the hydrophobic effect and the biocompatible properties of trehalose. Other investigators are encouraged to test and refine the approach taken here to further our understanding of solvent effects on molecular recognition.

16.
Int J Biol Macromol ; 256(Pt 2): 128411, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38016604

RESUMO

The development of high-strength and intrinsic flame-retardant natural fiber-reinforced green composite (NFRGC) is a landmark for high-performance structural applications. This paper reports a biobased, high-performance, flame-retardant composite material based on diverse bio-resources. Tough and strong cellulose long filaments (CLFs) are combined with vanillin-derived epoxy (VDE) resin to achieve high strength and flame-retardant NFRGC. The green composite was fabricated using a simple hand lay-up and compression molding technique. The green composite showed a noteworthy increment of 100.9 % flexural strength and 346 % flexural modulus compared to the neat VDE resin. Interestingly, despite the highly flammable nature of CLF, the green composite passes a V-0 rating under the UL-94 test, indicating excellent flame-retardant characteristics. Additionally, the green composite demonstrated outstanding hydrophobicity with a water contact angle of 104.2° and good chemical stability in various acidic and organic solvents. The green composite's excellent mechanical and physical properties show its potential for high-strength and flame-retardant structural applications.


Assuntos
Celulose , Retardadores de Chama , Benzaldeídos , Citoesqueleto , Resinas Epóxi
17.
ASAIO J ; 70(2): 93-98, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37862687

RESUMO

Advances in left ventricular assist device technologies have led to an improvement in pump hemocompatibility and outcomes. Because of concerns of thromboembolic complications in prior generations of left ventricular assist devices, bridging with parenteral anticoagulants was routinely. Management strategies of subtherapeutic INRs and their effects on the current generation of devices deserve review. We performed analysis of the MOMENTUM 3 trial including 6 centers in the mid-America region. Patients with subtherapeutic INRs (INR < 2) occurring after the index admission underwent chart review to determine the management strategies taken by clinicians. Strategies were divided into two groups, bridging or nonbridging. Of the 225 patients included in the analysis, 130 (58%) patients had a total of 235 subtherapeutic international normalized ratio (INR) events. Most (n = 179, 76.2%) of these INRs were not bridged (n = 100 warfarin dose adjustment, n = 79 no change in warfarin dose). Among those INRs (n = 56, 23.8%) treated with bridging, approximately half (n = 30, 53.6%) were treated with subcutaneous agents and other half (n = 26, 46.4%) were treated with intravenous agents. There was no difference in individual outcomes or composite endpoints of death, rehospitalization, CVA, or bleeding events between the groups.


Assuntos
Coração Auxiliar , Tromboembolia , Humanos , Varfarina/uso terapêutico , Coração Auxiliar/efeitos adversos , Anticoagulantes/uso terapêutico , Tromboembolia/etiologia , Tromboembolia/prevenção & controle , Hemorragia/etiologia , Coeficiente Internacional Normatizado , Estudos Retrospectivos
18.
Sensors (Basel) ; 23(24)2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38139496

RESUMO

Problem: Phonetic transcription is crucial in diagnosing speech sound disorders (SSDs) but is susceptible to transcriber experience and perceptual bias. Current forced alignment (FA) tools, which annotate audio files to determine spoken content and its placement, often require manual transcription, limiting their effectiveness. Method: We introduce a novel, text-independent forced alignment model that autonomously recognises individual phonemes and their boundaries, addressing these limitations. Our approach leverages an advanced, pre-trained wav2vec 2.0 model to segment speech into tokens and recognise them automatically. To accurately identify phoneme boundaries, we utilise an unsupervised segmentation tool, UnsupSeg. Labelling of segments employs nearest-neighbour classification with wav2vec 2.0 labels, before connectionist temporal classification (CTC) collapse, determining class labels based on maximum overlap. Additional post-processing, including overfitting cleaning and voice activity detection, is implemented to enhance segmentation. Results: We benchmarked our model against existing methods using the TIMIT dataset for normal speakers and, for the first time, evaluated its performance on the TORGO dataset containing SSD speakers. Our model demonstrated competitive performance, achieving a harmonic mean score of 76.88% on TIMIT and 70.31% on TORGO. Implications: This research presents a significant advancement in the assessment and diagnosis of SSDs, offering a more objective and less biased approach than traditional methods. Our model's effectiveness, particularly with SSD speakers, opens new avenues for research and clinical application in speech pathology.


Assuntos
Percepção da Fala , Voz , Humanos , Fonética , Fala , Patologistas
19.
Sci Prog ; 106(4): 368504231204759, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37787391

RESUMO

The washout motion cueing algorithm (MCA) is a critical element in driving simulators, designed to faithfully reproduce precise motion cues while minimizing false cues during simulation processes, particularly deceptive translational and rotational cues. To enhance motion sensation accuracy and optimize the use of available workspace, model predictive control (MPC) has been employed to develop innovative motion cueing algorithms. While most MCAs have been tailored for the Steward motion platform, there has been a recent adoption of the motion platform based on KUKA Robocoaster as an economical option for driving simulators. However, leveraging the full potential of the KUKA Robocoaster requires trajectory conversion of the motion base. Thus, this research proposes a novel MCA specifically designed for the KUKA Robocoaster-based motion platform, utilizing large planar circular motion to simulate lateral movement for drivers. Nonetheless, circular motion introduces disruptive centrifugal forces, which can be mitigated through proper pitch-tilted angles. The novel MPC generates simulated motion that accurately follows the lateral specific force target and effectively maintains the roll angular velocity below its threshold value. Additionally, it compensates for disturbing centrifugal acceleration by implementing pitch rotational motion, ensuring the pitch angular velocity remains below its threshold. Simulation tasks conducted on the motion platform, focusing solely on lateral acceleration, demonstrate the successful elimination of false motion cues in both the roll/sway and pitch/surge channels. The proposed innovative MPC solution offers an original approach to motion cueing algorithms in KUKA Robocoaster-based driving simulators. It enables the exploitation of the KUKA Robocoaster platform's capabilities while delivering accurate and immersive motion cues to drivers during simulation experiences.

20.
PLoS Negl Trop Dis ; 17(10): e0011728, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37903147

RESUMO

BACKGROUND: Shigella sonnei is a pathogen of growing global importance as a cause of diarrhoeal illness in childhood, particularly in transitional low-middle income countries (LMICs). Here, we sought to determine the incidence of childhood exposure to S. sonnei infection in a contemporary transitional LMIC population, where it represents the dominant Shigella species. METHODS: Participants were enrolled between the age of 12-36 months between June and December 2014. Baseline characteristics were obtained through standardized electronic questionnaires, and serum samples were collected at 6-month intervals over two years of follow-up. IgG antibody against S. sonnei O-antigen (anti-O) was measured using an enzyme-linked immunosorbent assay (ELISA). A four-fold increase in ELISA units (EU) with convalescent IgG titre >10.3 EU was taken as evidence of seroconversion between timepoints. RESULTS: A total of 3,498 serum samples were collected from 748 participants; 3,170 from the 634 participants that completed follow-up. Measures of anti-O IgG varied significantly by calendar month (p = 0.03). Estimated S. sonnei seroincidence was 21,451 infections per 100,000 population per year (95% CI 19,307-23,834), with peak incidence occurring at 12-18 months of age. Three baseline factors were independently associated with the likelihood of seroconversion; ever having breastfed (aOR 2.54, CI 1.22-5.26), history of prior hospital admission (aOR 0.57, CI 0.34-0.95), and use of a toilet spray-wash in the household (aOR 0.42, CI 0.20-0.89). CONCLUSIONS: Incidence of S. sonnei exposure in Ho Chi Minh City is substantial, with significant reduction in the likelihood of exposure as age increases beyond 2 years.


Assuntos
Disenteria Bacilar , Shigella , Humanos , Lactente , Pré-Escolar , Criança , Adolescente , Adulto Jovem , Adulto , Shigella sonnei , Vietnã/epidemiologia , Antígenos O , Imunoglobulina G , Disenteria Bacilar/epidemiologia
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