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1.
Small ; : e2309607, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38757541

RESUMO

Understanding the oxidation/reduction dynamics of secondary microparticles formed from agglomerated nanoscale primary particles is crucial for advancing electrochemical energy storage technologies. In this study, the behavior of individual copper hexacyanoferrate (CuHCF) microparticles is explored at both global and local scales combining scanning electrochemical microscopy (SECM), for electrochemical interrogation of a single, but global-scale microparticle, and optical microscopy monitoring to obtain a higher resolution dynamic image of the local electrochemistry within the same particle. Chronoamperometric experiments unveil a multistep oxidation/reduction process with varying dynamics. On the one hand, the global SECM analysis enables quantifying the charge transfer as well as its dynamics at the single microparticle level during the oxidation/reduction cycles by a redox mediator in solution. These conditions allow mimicking the charge storage processes in these particles when they are used as solid boosters in redox flow batteries. On the other hand, optical imaging with sub-particle resolution allows the mapping of local conversion rates and state-of-charge within individual CuHCF particles. These maps reveal that regions of different material loadings exhibit varying charge storage capacities and conversion rates. The findings highlight the significance of porous nanostructures and provide valuable insights for designing more efficient energy storage materials.

2.
Sports (Basel) ; 11(11)2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37999446

RESUMO

This study aimed to investigate the effects of a 6-week preseason functional and plyometric fitness training protocol, on physiological and biochemical markers of performance and exercise-induced muscle damage, and to compare the response of these markers between high-level female and male basketball players. The sample of the study consisted of 19 professional athletes (10 male; 9 female) competing in two different teams. The examined markers were body mass, BMI, fat percentage, speed, acceleration, explosiveness, vertical jumping ability, creatine kinase (CK) and lactate dehydrogenase (LDH). The preseason training period improved speed, acceleration, explosiveness and vertical jumping ability (~1-8%) and led to significant fat percentage reductions in both groups equivalently. CK and LDH increased similarly in both groups, and the percentage increases were higher for CK compared to LDH. Further investigation and a larger sample size are required in order to determine an approach that is more capable of maximizing performance without causing any possible injuries that may be related to muscle damage.

3.
J Phys Chem Lett ; 13(51): 11866-11871, 2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36520548

RESUMO

We report the experimental reassessment of the widely admitted concerted reduction mechanism for diazonium electroreduction. Ultrafast cyclic voltammetry was exploited to demonstrate the existence of a stepwise pathway, and real-time spectroelectrochemistry experiments allowed visualization of the spectral signature of an evolution product of the phenyldiazenyl radical intermediate. Unambiguous identification of the diazenyl species was achieved by radical trapping followed by X-ray structure resolution. The electrochemical generation of this transient under intermediate energetic conditions calls into question our comprehension of the layer structuration when surface modification is achieved via the diazonium electrografting technique as this azo-containing intermediate could be responsible for the systematic presence of azo bridges in nanometric films.

4.
J Am Chem Soc ; 144(49): 22734-22746, 2022 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-36468903

RESUMO

The electrocatalytic epoxidation of alkenes at heterogeneous catalysts using water as the sole oxygen source is a promising safe route toward the sustainable synthesis of epoxides, which are essential building blocks in organic chemistry. However, the physicochemical parameters governing the oxygen-atom transfer to the alkene and the impact of the electrolyte structure on the epoxidation reaction are yet to be understood. Here, we study the electrocatalytic epoxidation of cyclooctene at the surface of gold in hybrid organic/aqueous mixtures using acetonitrile (ACN) solvent. Gold was selected, as in ACN/water electrolytes gold oxide is formed by reactivity with water at potentials less anodic than the oxygen evolution reaction (OER). This unique property allows us to demonstrate that a sacrificial mechanism is responsible for cyclooctene epoxidation at metallic gold surfaces, proceeding through cyclooctene activation, while epoxidation at gold oxide shares similar reaction intermediates with the OER and proceeds via the activation of water. More importantly, we show that the hydrophilicity of the electrode/electrolyte interface can be tuned by changing the nature of the supporting salt cation, hence affecting the reaction selectivity. At low overpotential, hydrophilic interfaces formed using strong Lewis acid cations are found to favor gold passivation. Instead, hydrophobic interfaces created by the use of large organic cations favor the oxidation of cyclooctene and the formation of epoxide. Our study directly demonstrates how tuning the hydrophilicity of electrochemical interfaces can improve both the yield and selectivity of anodic reactions at the surface of heterogeneous catalysts.


Assuntos
Alcenos , Oxigênio , Alcenos/química , Ciclo-Octanos , Compostos de Epóxi/química , Ouro , Interações Hidrofóbicas e Hidrofílicas , Oxigênio/química , Água/química
5.
J Funct Morphol Kinesiol ; 7(4)2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36547662

RESUMO

Jumping ability in basketball is usually assessed using standardized vertical jump tests. However, they lack specificity and do not consider the player's basketball skills. Several studies have suggested performing specific jump tests, which are tailored to the movement patterns and requirements of a basketball game. The pivot step jump test (PSJT) is a novel test designed to evaluate the specific jumping abilities of basketball players by combining a pivot step on one leg with a maximum bilateral vertical jump. This study had two aims: to determine the reliability and validity of the PSJT using typical jump tests as the criterion measure and to demonstrate the PSJT as a practical test to evaluate specific jumping ability in young male and female basketball players. Twenty female (EGA; 14.0 ± 0.7 years, 59.3 ± 7.9 kg, 162.1 ± 5.5 cm) and fifteen male (EGB; 14.0 ± 0.7 years, 58.1 ± 7.7 kg, 170.3 ± 6.4 cm) basketball players participated in the study. The test−retest reliability of the PSJT within sessions (intrasession reliability) and across sessions (intersession reliability) was assessed within EGA. For the evaluation of validity, EGB performed the PSJT and a series of criterion jumping tests. For EGA, no changes (p > 0.05) were found in PSJT performance between test sessions and excellent intra- and intersession reliability was observed (ICCs > 0.75). Correlation coefficients indicated high factorial validity between the jumping tests and PSJT (r = 0.71−0.91, p < 0.001). The PSJT appears to offer a valid assessment of jumping ability in basketball and is a practical test for assessing sport-specific jumping skills in young basketball players.

6.
Sports (Basel) ; 10(6)2022 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-35736825

RESUMO

The pre-season period in basketball includes all the physiological attributes that the players need to work on and develop, in order to sustain a full season workload. The monitoring of the effectiveness of pre-season training is based on a variety of biochemical and physiological indices; however, it is still unclear how pre-season training affects those markers. Therefore, this study aimed to analyze the effects of pre-season training on biochemical and physiological markers. A search was performed in five large scientific databases (Pubmed (Medline), Scopus, Science-Direct, Sport-Discus (EBSCO), Semantic Scholar) and produced 7081 results, which after removing duplicates and applying inclusion and exclusion criteria, resulted in 28 published scientific articles being included in this review. The most important findings suggested that the majority of the studies used a 6- or an 8-week pre-season training protocol, because these protocols have shown significant positive effects over the years. In addition, the plyometric training protocols that were used by many studies have been found to be beneficial for basketball athletes for many physiological parameters. Furthermore, the evaluation of biochemical markers can be a very useful tool in monitoring and managing fatigue, which is an essential part of modifying the training process, in order to maximize performance.

7.
Chem Commun (Camb) ; 57(10): 1198-1201, 2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33427273

RESUMO

Oxidation of organic substrates is achieved in nature under mild conditions thanks to metalloenzymes but remains a challenge for chemists. Herein we show by UV-Vis spectroelectrochemistry that when MnIIITPPCl is electrochemically reduced to MnII in CH2Cl2 under O2, a MnIIO2˙ species is generated. Benzoic anhydride reacts with the latter triggering a catalytic current in cyclic voltammetry. Electrolysis on the catalytic wave in the presence of cyclooctene leads to its oxygenation or halogenation depending on the axial ligand present as reported here for the first time.

8.
Inorg Chem ; 59(16): 11577-11583, 2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32799464

RESUMO

O2 activation under mild conditions remains a weighty challenge for chemists. Herein we report a study of electrochemical O2 reductive activation catalyzed by FeIII(F20TPP)Cl, by means of cyclic voltammetry and UV-vis spectroelectrochemistry in acidic solutions of N,N-dimethylformamide. Two parallel catalytic pathways have been evidenced occurring at different overpotentials. At high overpotential a classical electron-proton (EPT) pathway where protonation of Fe peroxo ultimately leads to the formation of high-valent Fe oxo species dominates. At low overpotential a proton-electron (PET) pathway involving a hydrosuperoxo species has been identified.

9.
Angew Chem Int Ed Engl ; 59(38): 16376-16380, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32543058

RESUMO

Herein we report the first example of using scanning electrochemical microscopy (SECM) to quantitatively analyze O2 reductive activation in organic media catalyzed by three different Fe porphyrins. For each porphyrin, SECM can provide in one single experiment the redox potential of various intermediates, the association constant of FeII with O2 , and the pKa of the FeIII (OOH- )/ FeIII (OO2- ) couple. The results obtained can contribute to a further understanding of the parameters controlling the catalytic efficiency of the Fe porphyrin towards O2 activation and reduction.

10.
Int J Dermatol ; 59(6): 690-697, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32301503

RESUMO

BACKGROUND: Actinic keratosis (AK) is a chronic, precancerous skin disease. Various treatments options exist, including ingenol mebutate gel. The aim of this study was to compare its effectiveness and tolerability as well as the impact of therapy on patients' quality of life in standard clinical practice. METHODS: A multicenter study was carried out involving a 12-month follow-up period. A sample of 440 patients was included. Medical history details were recorded. Effectiveness, compliance to treatment, quality of life (EQ-5D-5L), and treatment satisfaction questionnaire for medication (TSQM-9) at week 8 were assessed. RESULTS: Of the total 440 patients, 428 (97.3%) attended at 8 weeks assessment. The number of patients with complete clearance was 337 (78.7%). EQ VAS score was significantly increased (P < 0.001). As far as TSQM-9 is concerned, patients with complete clearance reported statistically significantly higher satisfaction in effectiveness, convenience, and global satisfaction. At the 12-month follow-up visit, 323 patients (95.8%) retained their clearance status. Nineteen patients did not apply the ingenol mebutate gel on consecutive days. For these patients, the complete clearance rate was 42.1%, while for those who were treated on consecutive days, the complete clearance rate was 80.6%. None of our patients developed skin cancer. CONCLUSIONS: This study supports that ingenol mebutate is effective for the treatment of AK with a good safety profile. It significantly improves quality of life. Limited adherence to treatment might be associated with reduced effectiveness.


Assuntos
Diterpenos/administração & dosagem , Ceratose Actínica/tratamento farmacológico , Satisfação do Paciente/estatística & dados numéricos , Qualidade de Vida , Administração Cutânea , Adulto , Idoso , Diterpenos/efeitos adversos , Relação Dose-Resposta a Droga , Feminino , Seguimentos , Grécia , Humanos , Ceratose Actínica/diagnóstico , Ceratose Actínica/psicologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Recidiva , Índice de Gravidade de Doença , Inquéritos e Questionários/estatística & dados numéricos , Resultado do Tratamento , Escala Visual Analógica , Adulto Jovem
11.
Indian J Dermatol ; 64(3): 251, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31148873

RESUMO

Renal cell carcinoma (RCC) is the most frequent cancer of the kidney and it accounts for 3% of all solid malignancies. Although rare, cutaneous metastases can be an important manifestation of RCC. We present a case of a 56-year-old male with a history of RCC, followed by the development of cutaneous metastases 4 years later with an uncommon clinical presentation. RCC is the most common genitourinary cancer to metastasize to the skin and accounts for 6.8% of cutaneous metastases. These patients have a poor prognosis. It is essential for these patients to perform a complete periodic dermatologic examination for proper restaging and treatment.

13.
Res Sports Med ; 27(1): 112-120, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30126295

RESUMO

The purpose of the present study was to define the maximal lactate steady state (MLSSmeas) in high-level male basketball players and to compare it with the lactate turnpoint (LTP) and the respective point derived form a prediction method (MLSScal). Twelve high-level basketball players underwent one maximal and several submaximal tests on a treadmill on different days where MLSS and LTP were measured. MLSSmeas was observed at 75% of the maximal treadmill speed, at 77% of VO2max, at 88% of HRmax and at [La-] of 3.7 mmol.l-1. No differences were observed between MLSSmeas and LTP in any of the measured variables. A good agreement was observed between MLSSmeas and LTP, as well as between MLSSmeas and MLSScal. Therefore, LTP and MLSScal are offered as acceptable approaches to predict MLSS, but not all the indices used to define MLSS presents high agreement between the methods used.


Assuntos
Basquetebol/fisiologia , Teste de Esforço , Ácido Láctico/sangue , Adulto , Atletas , Humanos , Masculino , Consumo de Oxigênio
14.
Dermatol Online J ; 24(3)2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29634892

RESUMO

Psoriasis is one of the most frequently occurring chronic inflammatory skin diseases. There are some specialized regions of the body that are considered difficult to treat. Secukinumab is a human monoclonal immunoglobulin G antibody that blocks the interleukin 17A ligand and has been shown to be highly efficacious in treating moderate-to-severe psoriasis. We studied two Greek patients, one with scalp psoriasis and the other with palmoplantar psoriasis, both resistant to treatment. Patients were treated with secukinumab and efficacy and safety were recorded. The patient with severe, refractory palmoplantar psoriasis achieved complete clearance at the end of the 4-week treatment period with secukinumab. The patient with moderate to severe, chronic scalp psoriasis was successfully treated with secukinumab, obtaining complete clearance of symptoms and remission of disease after approximately 16 weeks. In both cases clinical response was maintained through week 52. Secukinumab has been shown to be highly efficacious in the treatment of psoriasis of specific anatomical sites with an acceptable safety profile.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Psoríase/tratamento farmacológico , Pele/patologia , Adulto , Anticorpos Monoclonais Humanizados , Grécia , Humanos , Masculino , Pessoa de Meia-Idade , Psoríase/patologia , Indução de Remissão , Índice de Gravidade de Doença
15.
J Hum Kinet ; 51: 121-129, 2016 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28149375

RESUMO

Team offense in basketball games consists of a set of offensive actions carried out with the cooperation of two or more players. Of these actions, the most commonly used in the last decade is the on-ball screen called the "pick and roll." The aim of this study was to analyze all of the pick and rolls conducted in the Euroleague championship from all of the 24 participating teams and to investigate the possible relationships between success in the pick and roll and overall success of the teams. For this purpose, 12,376 pick and rolls from 502 matches were analyzed and classified in categories according to the end result of the offensive possession. The results showed that the most effective type of pick and roll offense was when a shot was attempted after 2 passes from the pick and roll occurrence, followed by the screener's shot when he rolled to the basket. Additionally, linear regression analysis confirmed that pick and roll effectiveness could predict the final classification of the teams. Conclusively, coaches of the high level European clubs should focus on training the players to the most efficient phases of the pick and roll offense, so that the chances of winning the championship to be maximized.

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