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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.

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 physico-chemical 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 by 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.

International audience; 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.

International audience; O2 activation under mild conditions remains a weighty challenge for chemists. Herein we report a study of electrochemical O2 reductive activation catalyzed by Fe III (F20 TPP)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.

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

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.

This study examines the electromyographic activity of lower extremities and, in particular, of the tibialis anterior among young tennis players aged 12-16 years when performing three types of service, namely flat, slice and topspin. The study sample included 9 athletes. In order to record the muscle electric activity, three active surface electrodes were used with a pre-amplifier (Motion Control Co). Fluctuation analysis did not show statistically significant differences between parameters. Differences were observed in the activation sequence between the two muscles. In the flat service, the gastrocnemius is the first one activated, followed by the tibialis anterior. Maximum activation of the gastrocnemius occurs at initial lift-off, while the tibialis anterior towards the end of lift-off. In slice service, the two muscles are activated together and their maximum activation occurs when lift-off starts. In topspin service, the gastrocnemius is the first one activated, followed by the tibialis anterior. Maximum activation of the gastrocnemius occurs at initial lift-off, while the tibialis anterior towards the end of lift-off. Maximum activation of the two muscles occurred at the start of lift-off in all three service modes. In conclusion, young athletes need training to strengthen the tibialis anterior so as to improve lift-off velocity/acceleration in the service motion. Additionally, strengthening the tibialis anterior is a tool to improve foot lead. Such techniques are of the utmost importance during training so that skills as elaborate as those required for tennis service may be developed among young players.

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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.

Herein we report the first example of using scanning electrochemical microscopy (SECM) to quantitatively analyze O

Network providers either attempt to handle massive distributed denial-of-service attacks themselves or redirect traffic to third-party scrubbing centers. If providers adopt the first option, it is sensible to counter such attacks in their infancy via provider collaborations deploying distributed security mechanisms across multiple domains in an attack path. This motivated our work presented in this paper. Specifically, we investigate the establishment of trusted federations among adjacent and disjoint network domains, that is, autonomous systems (ASes) that collectively mitigate malicious traffic. Our approach is based on Distributed Ledger Technologies for signaling, coordination, and orchestration of a collaborative mitigation schema via appropriate blockchain-based smart contracts. Reputation scores are used to rank ASes based on their mitigation track record. The allocation of defense resources across multiple collaborators is modeled as a combinatorial optimization problem considering reputation scores and network flow weights. Malicious flows are mitigated using programmable network data paths within the eXpress Data Path (XDP) framework; this enables operators with enhanced packet processing throughput and advanced filtering flexibility. Our schema was implemented in a proof-of-concept prototype and tested under realistic network conditions.

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.

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 respectiv...

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.

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.

The aim of the present study is to examine the differences in gamerelated statistics which distinguished play offs and non-play offs participating teams in Euroleague Basketball. The sample included 1514 games played in all phases of Euroleague competition in the seasons 2012-2013, 2013-2014 and 2014-2015. The game related statistics which were used in the analysis were: Assists,Defensive Rebounds, Offensive Rebounds, Turnovers, Steals, Offensive and Defensive Efficiency in the form of Points per Possession and Defensive Points per Possession respectively. Discriminant analysis was conducted to distinguish the variables that best discriminate the two groups.The results revealed that play offs participating teams differ from those that were disqualified in: Defensive Rebounds, Points per Possession, and Defensive Points per Possession, Assists and Turnovers. This cross validation analysis provided 80.6% of successful classification. Coaches and basketball professionals can use discriminant models in recruiting, roster formation and practice organization and orientation in game tactics.

The purpose of this study was to record injuries in amateur males and females basketball players. These players participated in a domestic championship in Athens, during the 2000-2001 basketball season. An injury is considered the problem in musculoskeletal system that did not allow the player to continue the game or the training and might be out of the field for at least one day. Every injury was recorded by the coach of the team. From the start of the period until the end of the year 110 injuries in males and 86 in females were recorded. The rate was 0.72 injuries per male athlete per year, while for females the corresponding rate was 0.56. Males had more overuse injuries than females (p

The lipid profile of elite basketball and soccer athletes was evaluated and compared with that of inactive individuals. Total cholesterol (T-C), low and high density lipoprotein cholesterol (LDL-C and HDL-C), and triglyceride (TG) concentration were measured in the morning and after a soccer or a basketball match. All parameters of lipid profile measured at a fasted and resting state, except HDL-C, were lower in the athletes compared with the controls (p