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1.
Materials (Basel) ; 17(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38730826

RESUMO

Woven flax-carbon hybrid polyamide biocomposites offer a blend of carbon fibers' mechanical strength and flax's environmental advantages, potentially developing material applications. This study investigated their thermal behavior, degradation kinetics, and durability to water uptake and relative humidity exposure and compared them with pure flax and carbon composites with the same matrix. The hybrid composite exhibited intermediate water/moisture absorption levels between pure flax and carbon composites, with 7.2% water absorption and 3.5% moisture absorption. It also displayed comparable thermal degradation resistance to the carbon composite, effectively maintaining its weight up to 300 °C. Further analysis revealed that the hybrid composite exhibited a decomposition energy of 268 kJ/mol, slightly lower than the carbon composite's value of 288.5 kJ/mol, indicating similar thermal stability. Isothermal lifetime estimation, employing the activation energy (Ed) and degree of conversion facilitated by the Model Free Kinetics method, indicated a 41% higher service life of the hybrid laminate at room temperature compared to the carbon laminate. These insights are crucial for understanding the industrial applications of these materials without compromising durability.

2.
Materials (Basel) ; 17(9)2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38730861

RESUMO

Because of the high demand for carbon fiber reinforced polymer (CFRP) materials across all industries, the reuse and/or recycling of these materials (rCFRP) is necessary in order to meet the principles of the circular economy, including recycling and reuse. The objective of this study is to estimate the lifespan of thermoplastic matrix composite materials reinforced with waste materials (CFRP), which undergo only a mechanical cutting process. This estimation is carried out through the thermal decomposition of polymers, including polymer matrix composite materials, which is a complex process due to the numerous reactions involved. Some authors calculate these kinetic parameters using thermogravimetric analysis (TGA) as it is a quick method, and it allows the identification of gases released during decomposition, provided that the equipment is prepared for it. This study includes a comparison between polyamides 11 and 12, as well as between polyamide composite materials with carbon fiber (CF) and polyamides reinforced with CF/epoxy composite material. The latter is treated with plasma to improve adhesion with polyamides. The behavior of weight as a function of temperature was studied at speeds of 3, 6, 10, 13, 17, and 20 °C/min, finding stability of the polyamides up to a temperature of 400 °C, which was consistent with the analysis by mass spectroscopy, where gas evolution is evident after 400 °C. The estimation of the lifespan was carried out using two different methods including the Toop equation and the free kinetics model (MFK). The energy of the decomposition process was determined using the MFK model, which establishes the energy as a function of the degree of conversion. It is estimated that at 5% decomposition, mechanical properties are lost.

4.
Front Sports Act Living ; 6: 1335258, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38774279

RESUMO

Although whistleblowing is thought to represent an effective mechanism for detecting and uncovering doping in sport, it has yet to become a widely adopted practice. Understanding the factors that encourage or discourage whistleblowing is of vital importance for the promotion of this practice and the development of pedagogical material to enhance the likelihood of whistleblowing. The current study employed a qualitative methodology to explore the personal and organisational factors that underpin intentions to blow the whistle or that may lead to engagement in whistleblowing behaviours in sport. Thirty-three competitive athletes across a range of sports took part in a semi-structured interview which sought to explore what they would do should they encounter a doping scenario. Content analysis revealed that whistleblowing is a dynamic process characterised by the interaction of a range of personal and organisational factors in determining the intention to report PED use. These factors included moral reasoning, a desire to keep the matter "in-house", perceived personal costs, institutional attitudes to doping, and social support. Analysis revealed a number of "intervening events", including a perceived lack of organisational protection (e.g., ethical leadership) within some sporting sub-cultures, which present an important obstacle to whistleblowing. The intention to report doping was underpinned by a "fairness-loyalty trade-off" which involved athletes choosing to adhere to either fairness norms (which relate to a sense that all people and groups are treated equally) or loyalty norms (which reflect preferential treatment towards an in-group) when deciding whether they would blow the whistle. The promotion of fairness norms that emphasise a group's collective interests might encourage athletes to view whistleblowing as a means of increasing group cohesiveness and effectiveness and thereby increase the likelihood of this practice.

5.
Curr Issues Mol Biol ; 46(5): 3810-3821, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38785505

RESUMO

French Guiana, located in the Guiana Shield, is a natural reservoir for many zoonotic pathogens that are of considerable medical or veterinary importance. Until now, there has been limited data available on the description of parasites circulating in this area, especially on protozoan belonging to the phylum Apicomplexa; conversely, the neighbouring countries describe a high parasitic prevalence in animals and humans. Epidemiological surveillance is necessary, as new potentially virulent strains may emerge from these forest ecosystems, such as Amazonian toxoplasmosis. However, there is no standard tool for detecting protozoa in wildlife. In this study, we developed Meat-Borne-Parasite, a high-throughput meta-barcoding workflow for detecting Apicomplexa based on the Oxford Nanopore Technologies sequencing platform using the 18S gene of 14 Apicomplexa positive samples collected in French Guiana. Sequencing reads were then analysed with MetONTIIME pipeline. Thanks to a scoring rule, we were able to classify 10 samples out of 14 as Apicomplexa positive and reveal the presence of co-carriages. The same samples were also sequenced with the Illumina platform for validation purposes. For samples identified as Apicomplexa positive by both platforms, a strong positive correlation at up to the genus level was reported. Overall, the presented workflow represents a reliable method for Apicomplexa detection, which may pave the way for more comprehensive biomonitoring of zoonotic pathogens.

6.
PeerJ Comput Sci ; 10: e1898, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38660188

RESUMO

Data privacy is one of the biggest challenges facing system architects at the system design stage. Especially when certain laws, such as the General Data Protection Regulation (GDPR), have to be complied with by cloud environments. In this article, we want to help cloud providers comply with the GDPR by proposing a GDPR-compliant cloud architecture. To do this, we use model-driven engineering techniques to design cloud architecture and analyze cloud interactions. In particular, we develop a complete framework, called MDCT, which includes a Unified Modeling Language profile that allows us to define specific cloud scenarios and profile validation to ensure that certain required properties are met. The validation process is implemented through the Object Constraint Language (OCL) rules, which allow us to describe the constraints in these models. To comply with many GDPR articles, the proposed cloud architecture considers data privacy and data tracking, enabling safe and secure data management and tracking in the context of the cloud. For this purpose, sticky policies associated with the data are incorporated to define permission for third parties to access the data and track instances of data access. As a result, a cloud architecture designed with MDCT contains a set of OCL rules to validate it as a GDPR-compliant cloud architecture. Our tool models key GDPR points such as user consent/withdrawal, the purpose of access, and data transparency and auditing, and considers data privacy and data tracking with the help of sticky policies.

7.
Food Sci Nutr ; 12(4): 2588-2596, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38628189

RESUMO

Parental feeding practices, such as the use of food to soothe, can be shaped by various factors, including the family environment and parents' psychological characteristics and capacities. To our knowledge, the combined effect of these factors has not been studied. Furthermore, parental feeding practices have mainly been studied in women, resulting in a gender gap in the research. This study aims to investigate the combined effect of family environment and parental characteristics on the likelihood of using food to soothe children, taking the gender of both parents into account. This cross-sectional study included a sample of 846 parents (36.3% men) of 1-year-old children from different regions of Spain. Participants completed an online survey that included questionnaires to measure whether parents used food to soothe children, the family environment, parents' characteristics, and their psychological capacities. Binary logistic regression analyses were performed to identify associations between the variables. The final model showed that, within the family environment, higher levels of dyadic adjustment between couples (OR = 0.965; p = .026) were associated with a reduced likelihood of using food to soothe children, whereas the psychological characteristic of parental fatigue (OR = 1.053; p = .007) appeared to be associated with an increased likelihood. Also associated with an increased likelihood of this practice were higher parental sense of competence (OR = 1.028; p = .029) and the attention dimension of emotional intelligence (OR = 1.043; p = .007). Our study suggests that using food to soothe children may be influenced by factors at different levels, from the quality and adjustment of the couple's relationship to parental fatigue, self-competence, and emotional intelligence. For future research, it may be worthwhile contextualizing parental practices to gain a better understanding of children's behavior.

8.
Polymers (Basel) ; 16(7)2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38611136

RESUMO

Cavitation erosion poses a significant challenge in fluid systems like hydraulic turbines and ship propellers due to pulsed pressure from collapsing vapor bubbles. To combat this, various materials and surface engineering methods are employed. In this study, nano and micro scale particles of silicon carbide (SiC) or boron carbide (B4C) were incorporated as reinforcement at 6% and 12% ratios, owing to their exceptional resistance to abrasive wear and high hardness. Microparticles were incorporated to assess the damage incurred during the tests in comparison to nanoparticles. Wear tests were conducted on both bulk samples and coated aluminum sheets with a 1mm of composite. Additionally, cavitation tests were performed on coated aluminum tips until stability of mass loss was achieved. The results indicated a distinct wear behavior between the coatings and the bulk samples. Overall, wear tended to be higher for the coated samples with nanocomposites than bulk, except for the nano-composite material containing 12% SiC and pure resin. With the coatings, higher percentages of nanometric particles correlated with increased wear. The coefficient of friction remained within the range of 0.4 to 0.5 for the coatings. Regarding the accumulated erosion in the cavitation tests for 100 min, it was observed that for all nanocomposite materials, it was lower than in pure resin. Particularly, the composite with 6% B4C was slightly lower than the rest. In addition, the erosion rate was also lower for the composites.

9.
Microorganisms ; 12(3)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38543491

RESUMO

To discover potential micro(mi)RNA biomarkers of SARS-CoV-2 infection and disease progression, large-scale deep-sequencing analysis of small RNA expression was performed on plasma samples from 40 patients hospitalized for SARS-CoV-2 infection (median 13.50 [IQR 9-24] days since symptoms initiation) and 21 healthy noninfected individuals. A total of 1218 different miRNAs were identified. When compared with healthy noninfected donors, SARS-CoV-2-infected patients showed significantly (fold change [FC] > 1.2 and adjusted p [padj] < 0.05) altered expression of 190 miRNAs. The top-10 differentially expressed (DE) miRNAs were miR-122-5p, let-7b-5p, miR-146a-5p, miR-342-3p, miR-146b-5p, miR-629-5p, miR-24-3p, miR-12136, let-7a-5p, and miR-191-5p, which displayed FC and padj values ranging from 153 to 5 and 2.51 × 10-32 to 2.21 × 10-21, respectively, which unequivocally diagnosed SARS-CoV-2 infection. No differences in blood cell counts and biochemical plasma parameters, including interleukin 6, ferritin, and D-dimer, were observed between COVID-19 patients on high-flow oxygen therapy, low-flow oxygen therapy, or not requiring oxygen therapy. Notably, 31 significantly deregulated miRNAs were found, when patients on high- and low-flow oxygen therapy were compared. SARS-CoV-2 infection generates a specific miRNA signature in hospitalized patients. Specific miRNA profiles are associated with COVID-19 prognosis in patients requiring oxygen flow.

10.
J Travel Med ; 31(3)2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38381609

RESUMO

BACKGROUND: Up to 45% of febrile returning travellers remain undiagnosed after a thorough diagnostic work-up, even at referral centres. Although metagenomic next-generation sequencing (mNGS) has emerged as a promising tool, evidence of its usefulness in imported fever is very limited. METHODS: Travellers returning with fever were prospectively recruited in three referral clinics from November 2017 to November 2019. Unbiased mNGS optimised for virus detection was performed on serum samples of participants with acute undifferentiated febrile illness (AUFI), and results were compared to those obtained by reference diagnostic methods (RDM). RESULTS: Among 507 returned febrile travellers, 433(85.4%) presented with AUFI. Dengue virus (n = 86) and Plasmodium spp. (n = 83) were the most common causes of fever. 103/433(23.8%) AUFI remained undiagnosed at the end of the follow-up.Metagenomic next-generation sequencing unveiled potentially pathogenic microorganisms in 196/433(38.7%) AUFI. mNGS identifications were more common in patients with a shorter duration of fever (42.3% in ≤5 days vs 28.7% in >5 days, P = 0.005). Potential causes of fever were revealed in 25/103(24.2%) undiagnosed AUFI and 5/23(21.7%) travellers with severe undiagnosed AUFI. Missed severe aetiologies included eight bacterial identifications and one co-infection of B19 parvovirus and Aspergillus spp.Additional identifications indicating possible co-infections occurred in 29/316(9.2%) travellers with AUFI, and in 11/128(8.6%) travellers with severe AUFI, who had received a diagnosis through RDM. The most common co-infections detected in severe AUFI were caused by Gram-negative bacteria. Serum mNGS was unable to detect >50% of infectious diagnoses achieved by RDM and also yielded 607 non-pathogenic identifications. DISCUSSION: mNGS of serum can be a valuable diagnostic tool for selected travellers with undiagnosed AUFI or severe disease in addition to reference diagnostic techniques, especially during the first days of symptoms. Nevertheless, mNGS results interpretation presents a great challenge. Further studies evaluating the performance of mNGS using different sample types and protocols tailored to non-viral agents are needed.


Assuntos
Coinfecção , Doenças Transmissíveis , Humanos , Coinfecção/complicações , Febre/etiologia , Estudos de Coortes , Sensibilidade e Especificidade
11.
Polymers (Basel) ; 16(4)2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38399906

RESUMO

The main advantage of green composites is their biodegradability, but this biodegradability can also be considered a drawback if the degradation appears during the service life of the component. Therefore, the study of the mechanical behavior of green composites after hygrothermal aging tests is necessary to analyze their degradation process. This study aims to comprehensively analyze the hygrothermal aging behavior and aging mechanism of flax-fiber-reinforced polylactic acid (PLA) biocomposites. The fully biodegradable composites are manufactured by compression molding. In addition, the influence of atmospheric-pressure plasma treatment on the mechanical properties of the biocomposite is studied. Specimens are exposed to water vapor and 40 °C environmental conditions in a stove for up to 42 days. Several specimens of each type are taken out at regular intervals and tested to examine the water absorption, mechanical properties, and thermal characterization. The results show that the stiffness was significantly reduced after 24 h due to matrix degradation, while the strength was reduced only after three weeks.

13.
Clin Nephrol Case Stud ; 12: 17-21, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38352852

RESUMO

Waldenström's disease is a rare lymphoproliferative syndrome in the bone marrow and sometimes in lymphoid organs which secretes high amounts of monoclonal immunoglobulin M into serum. It can remain indolent for years and rarely affects the kidney, with intraglomerular rather than intratubular damage being predominant, in contrast to multiple myeloma. Different studies identified AL amyloidosis as the most frequent renal lesion, followed by cryoglobulinemic glomerulonephritis. Signs and symptoms may be unspecific, as well as renal manifestations, so collaboration between nephrologists, hematologists, and pathologists is crucial to establish the role of paraprotein in the development of renal damage. We present an atypical case of Waldenström's disease that had a minimal monoclonal peak and clinically debuted with nephritic and nephrotic syndromes. The diagnosis was cryoglobulinemic glomerulonephritis. Currently, there are numerous treatment options, without enough evidence yet to establish a standardised treatment.

14.
J Hum Kinet ; 90: 151-159, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38380308

RESUMO

The aim of this study was to analyse the effects of different recovery times between bouts of small-sided games (SSG) on external and internal load variables in semi-professional soccer players. Sixteen male semi-professional soccer players performed three 4 vs. 4 + goalkeeper SSG training sessions, each with different recovery bout duration: short (1 min) (SSG1), medium (2 min) (SSG2), and long (4 min) (SSG4). Time motion and neuromuscular measures were collected during all SSGs, in addition, the rating of perceived exertion (RPE) was determined at the end of the last bout of each SSG. Results showed a significant increase in the total number of accelerations (p = 0.016, ES = 0.97, large) and decelerations (p = 0.022, ES = 0.81, large) in SSG4 compared to SSG1. In terms of the internal load, SSG2 showed significantly higher RPE values (p = 0.011, ES = 1.00, large) in comparison with SSG1. If the sessions' focus is on neuromuscular training, longer recovery times between SSG bouts should be used. Conversely, if the aim is to reach a higher total and running distance at different intensities, a 2-min recovery period between bouts may be more appropriate.

15.
J Clin Nurs ; 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38258512

RESUMO

OBJECTIVES: To explore the rate of NUPs and associated factors in the PED of the 'Hospital Universitario y Politécnico La Fe' in Valencia (Spain) using Andersen's Behavioural Model. METHODS: We conducted a descriptive cross-sectional study using Andersen's Behavioural Model in parents visiting the PED with their children at the 'Hospital Universitario y Politécnico La Fe' in Valencia (Spain). RESULTS: The study involved a total of 530 participants, of whom 419 (79%) had made an NUP. The predisposing factors identified were: (I) paediatric patients brought in by their fathers (OR = 0.460; p = 0.005), (II) lower educational attainment (OR = 3.841; p = 0.000), (III) first-time parenthood (OR = 2.335; p = 0.000) and (IV) higher parental stress (OR = 1.974; p = 0.023). The enabling factors included: (I) responsibility for a significant part of the childcare shared with others (OR = 0.348; p = 0.041) and (II) the perception that PEDs provide better care than primary care (PC) services (OR = 1.628; p = 0.005). The need factors were: (I) existing chronic illness in the child seeking care (OR = 0.343; p = 0.000) and (II) the perceived severity of the urgency (OR = 0.440; p = 0.031). CONCLUSIONS: The NUP rates found in this study are similar to those found internationally. In accordance with Andersen's Behavioural Model, we identify predisposing, enabling and need factors to explain the multifactorial nature of NUPs in PEDs. IMPLICATIONS FOR PRACTICE: Identifying the factors associated with NUPs enables interventions to be targeted at those groups most likely to engage in NUPs, thereby optimising the functioning of the PED and improving the well-being of children and families. These interventions should focus on improving parental health literacy, providing education on making appropriate decisions about accessing health services and recognising severe symptoms in children, as well as improving access to high-quality PC services. Providing support to parents during the transition to parenthood would also be beneficial. REPORTING METHOD: This paper adheres to the STROBE initiative guidelines. CONTRIBUTION FROM PATIENTS OR MEMBERS OF THE PUBLIC: Participants, who voluntarily agreed to take part, contributed to the study by completing a paper-based questionnaire containing all the study variables as prepared by the research team.

18.
Biol Sport ; 41(1): 153-161, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38188102

RESUMO

The aims of this study were to: (a) determine the differences in external load quantification between arbitrary and individual speed thresholds over the weekly microcycle in professional soccer players, and (b) analyse the association between internal load and different external load quantification strategies (ELQSs). Ten professional outfield players were monitored during training sessions and official matches using 10 Hz GPS devices over a 6-week in-season period. The absolute and relative ("R" before the distance category) distances covered were calculated for the following external load variables: medium-intensity running distance (MIR), high-intensity running (HIR), sprint distance (SD), and very high-intensity running (VHIR). Individualized thresholds were determined based on maximal sprinting speed (MSS) and the last speed achieved during the 30-15 Intermittent Fitness Test (VIFT) of each player. In terms of match-day workload, significant differences (p < 0.05) were observed between arbitrary and individualized strategies (i.e., MSS and VIFT) for the distance covered in MIR, HIR, SD, VHIR, RHIR, RSD, and RVHIR. The MSS strategy compared to arbitrary thresholds revealed significant differences (p < 0.05) for distance covered in HIR, RHIR, and VHIR during all training sessions. The present results showed that arbitrary thresholds lead to underestimation of external load absolute and relative metrics compared to the MSS strategy throughout the microcycle. The VIFT strategy mainly revealed differences in external load quantification regarding MD compared to arbitrary thresholds. Individualized speed threshold strategies did not achieve better associations with internal load measures in comparison with arbitrary thresholds in professional soccer players.

19.
ACS Biomater Sci Eng ; 10(2): 987-997, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38234159

RESUMO

A combination of human-induced pluripotent stem cells (hiPSCs) and 3D microtissue culture techniques allows the generation of models that recapitulate the cardiac microenvironment for preclinical research of new treatments. In particular, spheroids represent the simplest approach to culture cells in 3D and generate gradients of cellular access to the media, mimicking the effects of an ischemic event. However, previous models required incubation under low oxygen conditions or deprived nutrient media to recreate ischemia. Here, we describe the generation of large spheroids (i.e., larger than 500 µm diameter) that self-induce an ischemic core. Spheroids were generated by coculture of cardiomyocytes derived from hiPSCs (hiPSC-CMs) and primary human cardiac fibroblast (hCF). In the proper medium, cells formed aggregates that generated an ischemic core 2 days after seeding. Spheroids also showed spontaneous cellular reorganization after 10 days, with hiPSC-CMs located at the center and surrounded by hCFs. This led to an increase in microtissue stiffness, characterized by the implementation of a constriction assay. All in all, these phenomena are hints of the fibrotic tissue remodeling secondary to a cardiac ischemic event, thus demonstrating the suitability of these spheroids for the modeling of human cardiac ischemia and its potential application for new treatments and drug research.


Assuntos
Isquemia Miocárdica , Miócitos Cardíacos , Humanos , Constrição , Células Cultivadas , Isquemia
20.
Nephrol Dial Transplant ; 39(2): 328-340, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-37550217

RESUMO

BACKGROUND: The role of sodium-glucose cotransporter 2 inhibitors (SGLT2i) in the management glomerular/systemic autoimmune diseases with proteinuria in real-world clinical settings is unclear. METHODS: This is a retrospective, observational, international cohort study. Adult patients with biopsy-proven glomerular diseases were included. The main outcome was the percentage reduction in 24-h proteinuria from SGLT2i initiation to 3, 6, 9 and 12 months. Secondary outcomes included percentage change in estimated glomerular filtration rate (eGFR), proteinuria reduction by type of disease and reduction of proteinuria ≥30% from SGLT2i initiation. RESULTS: Four-hundred and ninety-three patients with a median age of 55 years and background therapy with renin-angiotensin system blockers were included. Proteinuria from baseline changed by -35%, -41%, -45% and -48% at 3, 6, 9 and 12 months after SGLT2i initiation, while eGFR changed by -6%, -3%, -8% and -10.5% at 3, 6, 9 and 12 months, respectively. Results were similar irrespective of the underlying disease. A correlation was found between body mass index (BMI) and percentage proteinuria reduction at last follow-up. By mixed-effects logistic regression model, serum albumin at SGLT2i initiation emerged as a predictor of ≥30% proteinuria reduction (odds ratio for albumin <3.5 g/dL, 0.53; 95% CI 0.30-0.91; P = .02). A slower eGFR decline was observed in patients achieving a ≥30% proteinuria reduction: -3.7 versus -5.3 mL/min/1.73 m2/year (P = .001). The overall tolerance to SGLT2i was good. CONCLUSIONS: The use of SGLT2i was associated with a significant reduction of proteinuria. This percentage change is greater in patients with higher BMI. Higher serum albumin at SGLT2i onset is associated with higher probability of achieving a ≥30% proteinuria reduction.


Assuntos
Diabetes Mellitus Tipo 2 , Glomerulonefrite , Nefropatias , Adulto , Humanos , Pessoa de Meia-Idade , Estudos de Coortes , Nefropatias/complicações , Glomerulonefrite/tratamento farmacológico , Glomerulonefrite/complicações , Proteinúria/etiologia , Proteinúria/complicações , Albumina Sérica , Sódio , Glucose , Diabetes Mellitus Tipo 2/complicações
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