Correction: catalytic enantioselective synthesis of α-nitroepoxides via aminolytic kinetic resolution

Correction for 'Catalytic enantioselective synthesis of α-nitroepoxides via aminolytic kinetic resolution' by Sara Meninno et al., Catal. Sci. Technol., 2015, 5, 124–128

Hierarchical cluster analysis for pattern recognition of process conditions in die sinking EDM process monitoring

Abstract Die sinking EDM processes require continuous monitoring due to the typically severe application requirements, especially in advanced aerospace parts machining, where part quality and machining time are main concerns. As the process conditions cannot be recognized based on the behaviour of a single monitored value, it is necessary to consider a number of relevant sensor signals together. The aim of this research work is to recognize the machining conditions which lead to an improper process performance, e.g. by increasing machining time and causing unacceptable part quality, and to highlight the most relevant sensorial features. Using the Real Time Acquisition (RTAQ) module installed on an AgieCharmilles FORM P 600 sinker spark erosion machine, eight process parameters are acquired. Hierarchical cluster analysis is then applied to identify different groups of improper process conditions based on relevant features extracted from the EDM process parameters

Il contributo dei QSO a z - 4 al Fondo Ionizzante Intergalattico.

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Effects of Chickpea in Substitution of Soybean Meal on Milk Production, Blood Profile and Reproductive Response of Primiparous Buffaloes in Early Lactation

This study aimed to evaluate the effects of the use of chickpea meal in substitution of soybean meal on plasma metabolites, reproductive response, milk yield and composition and milk coagulation traits of primiparous buffaloes in early lactation. Eighteen primiparous buffaloes were blocked by age, body weight and days in milk and equally allotted to two experimental groups from 10 to 100 days of lactation. The experimental diets consisted of the same forage integrated with two different isonitrogenous and isoenergetic concentrates containing either 210 g/kg of soybean meal or 371 g/kg chickpea. The use of chickpea meal had no negative effects on dry matter intake (p = 0.69), body condition score (p = 0.33) and milk yield (p = 0.15). Neither milk composition nor blood metabolites were influenced by dietary treatments (p > 0.05), but an increment of urea concentrations in milk (p 0.05) of the dietary treatment was highlighted on milk coagulation traits as well as buffalo reproductive responses. We concluded that soybean meal can be replaced by chickpea meal in the diet for primiparous dairy buffaloes in the early lactation period without impairing their productive and reproductive performance

Dimensionality Reduction of Sensorial Features by Principal Component Analysis for ANN Machine Learning in Tool Condition Monitoring of CFRP Drilling

Abstract With the aim to perform sensor monitoring of tool conditions in drilling of stacks made of two carbon fiber reinforced plastic (CFRP) laminates, a machine learning procedure based on the acquisition and processing of thrust force, torque, acoustic emission and vibration sensor signals during drilling is developed. From the acquired sensor signals, multiple sensorial features are extracted to feed artificial neural network-based machine learning paradigms, and an advanced feature extraction methodology based on Principal Component Analysis (PCA) is implemented to decrease the dimensionality of sensorial features via linear projection of the original features into a new space. By feeding artificial neural networks with the PCA features, the diagnosis of tool flank wear is accurately carried out

Unimolecular Variant of the Fluorescence Turn-On Oxidative Coupling of Catecholamines with Resorcinols

Reported herein is a unimolecular variant of the fluorescence turn-on oxidative coupling of catecholamines with resorcinols ("FluoResCat") based on the easily accessible conjugate 4-(2-((2,4-dihydroxybenzyl)amino)ethyl)benzene-1,2-diol (1). The process involves an alkali-activatable sequence of autoxidation and intramolecular cyclization steps with loss of carbon, leading to a fluorescent methanobenzofuroazocinone product identical to that obtained from the oxidative coupling of dopamine with resorcinol. A mechanistic route for this unexpected reaction, mimicking the synthesis of the natural fluorophore matlaline, would involve highly constrained polycyclic spiro intermediates (liquid chromatography–mass spectrometry analysis of intermediates, model reactions, and density functional theory calculations). Emission turn-on from 1 in response to oxygen, superoxide-generating systems, or gaseous ammonia/volatile amines may be of interest for sensing applications, for example, in smart packaging

Time-resolved EPR investigation of oxygen and temperature effects on synthetic eumelanin

Synthetic eumelanin produced using 5,6-dihydroxyindole-2-carboxylic acid as precursor and H2O2/horseradish peroxidase as oxidative reagent, in form of dry powder, has been investigated under photoexcitation by TR-EPR spectroscopy. The formation of spin polarized radical pairs from triplet excited states of melanin has been observed both in absence and in presence of oxygen and has been followed as a function of the temperature in the range 140–290 K. The triplet mechanism explains the observed polarization pattern in net emission. In the presence of oxygen new radical pairs are formed by interaction of melanin with molecular oxygen

Resveratrol-based benzoselenophenes with an enhanced antioxidant and chain breaking capacity

The structural modification of the resveratrol scaffold is currently an active issue in the quest for more potent and versatile antioxidant derivatives for biomedical applications. Disclosed herein is an expedient and efficient entry to a novel class of resveratrol derivatives featuring an unprecedented 2-phenylbenzoselenophene skeleton. The new compounds were obtained in good yields by direct selenenylation of resveratrol with Se(0) and SO2Cl2 in dry THF. Varying the [Se:SO2Cl2:resveratrol] ratio resulted in the formation of the parent benzoselenophene (1) and/or mono (2) and/or dichloro (3) benzoselenophene derivatives. All the benzoselenophene derivatives proved to be more efficient than resveratrol in the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing/antioxidant power (FRAP) assays, with 1 showing an activity nearly comparable to that of Trolox. 1-3 also proved to be more efficient inhibitors than the parent resveratrol in kinetic experiments of styrene autoxidation. DFT calculations of the O-H bond dissociation enthalpy (BDE) revealed that the introduction of the Se-atom causes a significant decrease of the BDE of 3-OH and 5-OH, with just a small increase of the 4′-OH BDE. Compounds 1-3 showed no cytotoxicity at 5 μM concentrations on human keratinocyte (HaCaT) and intestinal (CaCo-2) cell line

Consequences of simulated microgravity in neural stem cells: biological effects and metabolic response.

Objective: Microgravity was often shown to cause cell damage and impair cell cycle in a variety of biological systems. Since the effects on the neural system were poorly investigated, we aimed to gain insight into how biological processes such as cell cycle, cell damage, stemness features and metabolic status are involved in neural stem cells (NSC) when they experience simulated microgravity. We also wished to investigate whether these modulations were transient or permanent once cells were returned to normal gravity. Methods: NSC were isolated from mouse cerebella and cultured in the Rotary Cell Culture System (RCCS) to model microgravity. We analyzed cell cycle, stress and apoptotic response. We also performed a 1H NMR-based metabolomic analysis and evaluation of stemness features of NSC in simulated microgravity and once in the returned to normogravity cell culture. Results: Biological processes and metabolic status were modulated by simulated microgravity. Cells were arrested in S-phase together with enhanced apoptosis. Metabolic changes occurred in NSC after simulated microgravity. Interestingly, these modulations were transient. Indeed, stemness features and metabolic footprint returned to basal levels after few days of culture in normal conditions. Moreover NSC clonogenic ability was not impaired. Conclusions: Our data suggest that simulated microgravity impacts on NSC biological processes, including cell cycle and apoptosis. However, NSC does not suffer from permanent damage