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Energy systems development

Justin A Lemkul, Alexander D MacKerell
Mg2+ ions are important in biological systems, particularly in stabilizing compact RNA folds. Mg2+ is strongly polarizing, and representing its interactions in heterogeneous environments is a challenge for empirical force field development. To date, the most commonly used force fields in molecular dynamics simulations utilize a pairwise-additive approximation for electrostatic interactions, which cannot account for the significant polarization response in systems containing Mg2+. In the present work, we refine the interactions of Mg2+ with water, Cl- ions, and nucleic acid moieties using a polarizable force field based on the classical Drude oscillator model...
October 19, 2016: Journal of Physical Chemistry. B
Pablo M Piaggi, Omar Valsson, Michele Parrinello
We study by computer simulation the nucleation of a supersaturated Lennard-Jones vapor into the liquid phase. The large free energy barriers to transition make the time scale of this process impossible to study by ordinary molecular dynamics simulations. Therefore we use a recently developed enhanced sampling method [Valsson and Parrinello, Phys. Rev. Lett.113, 090601 (2014)] based on the variational determination of a bias potential. We differ from previous applications of this method in that the bias is constructed on the basis of the physical model provided by the classical theory of nucleation...
October 18, 2016: Faraday Discussions
L Maïmoun, F Paris, O Coste, C Sultan
Participation in recreational physical activity is widely acknowledged to provide significant health benefits. Conversely, intense training imposes several constraints, such as intermittent or chronic metabolic and psychogenic training stressors and maintenance of very low body fat to maximize performance. Adolescent and adult athletic women are therefore at risk of overtraining and/or poor dietary intake, which may have several consequences for endocrine function particularly on hypothalamic-pituitary-gonadal axis...
October 14, 2016: Gynécologie, Obstétrique & Fertilité
Dongqing Kong, Sai Bi, Zonghua Wang, Jianfei Xia, Feifei Zhang
In this work, an in situ growth protocol is introduced to fabricate three-dimensional graphene films (3D GFs) on gold substrates, which are successfully utilized as working electrode for electrochemical detection of nucleic acid (microRNA) and protein (lysozyme) based on a signal-on sensing mechanism. To realize the bridge between the gold substrate and graphene film, a monolayer of 4-aminothiophenol is self-assembled on the substrate, which is then served as connectors for the growth of 3D GFs on the gold substrate by the hydrothermal reduction (HR) technique...
October 18, 2016: Analytical Chemistry
W Liu, J Wang, M Li, W Tang, J Han
We previously developed a lutein-polyvinylpyrrolidone (PVP) complex with improved aqueous saturation solubility and stability, though the conjugation mechanism is still unclear. In this paper, experiments with astaxanthin-PVP complex and curcumin-PVP complex were carried out, which indicated that PVP could improve the solubility and stability of astaxanthin and curcumin. We aimed to construct a computational model capable of understanding the protective effect in complexes formed between PVP and antioxidants, through which the binding mode of PVP and antioxidants was investigated with molecular modelling in order to obtain the interactions, binding energy, binding site and surface area between PVP and antioxidants...
October 17, 2016: SAR and QSAR in Environmental Research
Claudia Crocini, Cecilia Ferrantini, Raffaele Coppini, Marina Scardigli, Ping Yan, Leslie M Loew, Godfrey Smith, Elisabetta Cerbai, Corrado Poggesi, Francesco S Pavone, Leonardo Sacconi
Current rescue therapies for life-threatening arrhythmias ignore the pathological electro-anatomical substrate and base their efficacy on a generalized electrical discharge. Here, we developed an all-optical platform to examine less invasive defibrillation strategies. An ultrafast wide-field macroscope was developed to optically map action potential propagation with a red-shifted voltage sensitive dye in whole mouse hearts. The macroscope was implemented with a random-access scanning head capable of drawing arbitrarily-chosen stimulation patterns with sub-millisecond temporal resolution allowing precise epicardial activation of Channelrhodopsin2 (ChR2)...
October 17, 2016: Scientific Reports
He Zhu, Fernando A Wilson, Jim P Stimpson, Peter E Hilsenrath
BACKGROUND: We examined whether sales of new motorcycles was a mechanism to explain the relationship between motorcycle fatalities and gasoline prices. METHODS: The data came from the Motorcycle Industry Council, Energy Information Administration and Fatality Analysis Reporting System for 1984-2009. Autoregressive integrated moving average (ARIMA) regressions estimated the effect of inflation-adjusted gasoline price on motorcycle sales and logistic regressions estimated odds ratios (ORs) between new and old motorcycle fatalities when gasoline prices increase...
December 2015: Injury Epidemiology
Marcelo Augusto Pinto Cardoso Goularte, Gustavo Frainer Barbosa, Nilson Cristino da Cruz, Luciana Mayumi Hirakata
BACKGROUND: Search for materials that may either replace titanium dental implants or constitute an alternative as a new dental implant material has been widely studied. As well, the search for optimum biocompatible metal surfaces remains crucial. So, the aim of this work is to develop an oxidized surface layer on tantalum using plasma electrolytic oxidation (PEO) similar to those existing on oral implants been marketed today. METHODS: Cleaned tantalum samples were divided into group 1 (control) and groups 2, 3, and 4 (treated by PEO for 1, 3, and 5 min, respectively)...
December 2016: Int J Implant Dent
M A Sokoto, Rawel Singh, Bhavya B Krishna, Jitendra Kumar, Thallada Bhaskar
Thermal decomposition and kinetics behaviour of the de-oiled seed cake of African star apple (Chrosophyllum albidum) has been investigated using thermogravimetry under the nitrogen atmosphere from ambient temperature to 900 °C. The thermogravimetric data for the cake decomposition at six different heating rates (5, 10, 15, 20, 30 and 40 °C/min) were used to evaluate the kinetic decomposition of the cake using Friedman (FD), Kissinger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO) models. Thermal decomposition of the cake showed thermograms indicating dehydration and devolitilization stages (200-400 °C)...
October 2016: Heliyon
Mar Margalef-Català, Isabel Araque, Albert Bordons, Cristina Reguant, Joaquín Bautista-Gallego
Oenococcus oeni, the main lactic acid bacteria responsible for malolactic fermentation in wine, has to adapt to stressful conditions, such as low pH and high ethanol content. In this study, the changes in the transcriptome and the proteome of O. oeni PSU-1 during the adaptation period before MLF start have been studied. DNA microarrays were used for the transcriptomic analysis and two complementary proteomic techniques, 2-D DIGE and iTRAQ labeling were used to analyze the proteomic response. One of the most influenced functions in PSU-1 due to inoculation into wine-like medium (WLM) was translation, showing the over-expression of certain ribosomal genes and the corresponding proteins...
2016: Frontiers in Microbiology
Ana V Ferreira, Ilana Perelshtein, Nina Perkas, Aharon Gedanken, Joana Cunha, Artur Cavaco-Paulo
Chronic wound fluids have elevated concentration of human neutrophil elastase (HNE) which can be used as inflammation/infection marker. Our goal is to develop functional materials for fast diagnosis of wound inflammation/infection by using HNE as a specific marker. For that, fluorogenic peptides with a HNE-specific cleavage sequence were incorporated into traditional textile dressings, to allow real-time detection of the wound status. Two different fluorogenic approaches were studied in terms of intensity of the signal generated upon HNE addition: a fluorophore 7-amino-4-trifluormethylcoumarin (AFC) conjugated to a HNE-specific peptide and two fluorophore/quencher pairs (FAM/Dabcyl and EDANS/Dabcyl) coupled to a similar peptide as a Förster resonance energy transfer (FRET) strategy...
October 15, 2016: Applied Microbiology and Biotechnology
Joana F Sacramento, Maria J Ribeiro, Tiago Rodrigues, Elena Olea, Bernardete F Melo, Maria P Guarino, Rui Fonseca-Pinto, Cristiana R Ferreira, Joana Coelho, Ana Obeso, Raquel Seiça, Paulo Matafome, Sílvia V Conde
AIMS/HYPOTHESIS: We recently described that carotid body (CB) over-activation is involved in the aetiology of insulin resistance and arterial hypertension in animal models of the metabolic syndrome. Additionally, we have demonstrated that CB activity is increased in animal models of insulin resistance, and that carotid sinus nerve (CSN) resection prevents the development of insulin resistance and arterial hypertension induced by high-energy diets. Here, we tested whether the functional abolition of CB by CSN transection would reverse pre-established insulin resistance, dyslipidaemia, obesity, autonomic dysfunction and hypertension in animal models of the metabolic syndrome...
October 16, 2016: Diabetologia
I Velázquez-López, E León-Cruz, J P Pardo, A Sosa-Peinado, M González-Andrade
Eight new fluorescent biosensors of human calmodulin (hCaM) using Alexa Fluor(®) 350, 488, 532, and 555 dyes were constructed. These biosensors are thermodynamically stable, functional, and highly sensitive to ligands of the CaM. They resolve the problem of CaM ligands with similar spectroscopic properties to the intrinsic and extrinsic fluorophores of other biosensors previously reported. Additionally, they can be used in studies of protein-protein interaction through Förster resonance energy transfer (FRET)...
October 12, 2016: Analytical Biochemistry
M Yoshimura, K Moriwaki, S Noto, T Takiguchi
: Although an osteoporosis screening program has been implemented as a health promotion project in Japan, its cost-effectiveness has yet to be elucidated fully. We performed a cost-effectiveness analysis and found that osteoporosis screening and treatment would be cost-effective for Japanese women over 60 years. INTRODUCTION: The purpose of this study was to estimate the cost-effectiveness of osteoporosis screening and drug therapy in the Japanese healthcare system for postmenopausal women with no history of fracture...
October 14, 2016: Osteoporosis International
Brent Robert Heard, Shelie A Miller
The unbroken global refrigerated supply chain, or cold chain, is rapidly expanding in developing countries. In addition to increasing the energy intensity of the food system, the expanded cold chain may facilitate changes in the global diet, food waste patterns, food production and distribution, and shopping habits. The sustainability impacts of many of these changes chain are unknown, given the complexity of interacting social, economic, and technical factors. The current literature surrounding the environmental impacts of refrigeration in the food system focuses on the direct impacts of energy use and coolant emissions, and lacks a critical evaluation of the accompanying systemic societal changes that potentially carry greater environmental impacts...
October 14, 2016: Environmental Science & Technology
Albert R Jones Iv, Tova Meshulam, Marcus F Oliveira, Nathan Burritt, Barbara E Corkey
BACKGROUND: Many tissues play an important role in metabolic homeostasis and the development of diabetes and obesity. We hypothesized that the circulating redox metabolome is a master metabolic regulatory system that impacts all organs and modulates reactive oxygen species (ROS) production, lipid peroxidation, energy production and changes in lipid turnover in many cells including adipocytes. METHODS: Differentiated human preadipocytes were exposed to the redox couples, lactate (L) and pyruvate (P), β-hydroxybutyrate (βOHB) and acetoacetate (Acoc), and the thiol-disulfides cysteine/ cystine (Cys/CySS) and GSH/GSSG for 1...
2016: PloS One
Daniel Sanchez-Parcerisa, Maura Kirk, Marcus Fager, Brendan Burgdorf, Malorie Stowe, Tim Solberg, Alejandro Carabe
The development of rotational proton therapy plans based on a pencil-beam-scanning (PBS) system has been limited, among several other factors, by the energy-switching time between layers, a system-dependent parameter that ranges between a fraction of a second and several seconds. We are investigating mono- and bi-energetic rotational proton modulated arc therapy (PMAT) solutions that would not be affected by long energy switching times. In this context, a systematic selection of the optimal proton energy for each arc is vital...
October 14, 2016: Physics in Medicine and Biology
Juan D Rojas, Paul A Dayton
Sub-micron phase-change contrast agents consist of a liquid perfluorocarbon core that can be vaporized by ultrasound (acoustic droplet vaporization) to generate contrast with excellent spatial and temporal control. When these agents, commonly referred to as nanodroplets, are formulated with cores of low boiling-point perfluorocarbons such as decafluorobutane and octafluoropropane, they can be activated with lowmechanical index imaging pulses for diagnostic applications. Since the utilization of minimum mechanical index is often desirable to avoid unnecessary biological effects, enabling consistent activation of these agents in an acoustic field is a challenge because the energy that must be delivered to achieve the vaporization threshold increases with depth due to attenuation...
October 12, 2016: IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
Giacomo M Lari, Olivier G Gröninger, Qiang Li, Cecilia Mondelli, Núria López, Javier Pérez-Ramírez
Sugar alcohols are applied in the food, pharmaceutical, polymer, and fuel industries and are commonly obtained by reduction of the corresponding saccharides. In view of the rarity of some sugar substrates, epimerization of a readily available monosaccharide has been proposed as a solution, but an efficient catalytic system has not yet been identified. Herein, a molybdenum heteropolyacid-based catalyst is developed to transform glucose, arabinose, and xylose into less-abundant mannose, ribose, and lyxose, respectively...
October 14, 2016: ChemSusChem
Viktor A Vorozhtcov, Valentina L Stolyarova, Sergey I Lopatin, Sergey M Shugurov, Andrey L Shilov, Vladimir F Sapega
RATIONALE: The Bi2 O3 -P2 O5 -SiO2 system possesses a number of valuable properties that may be of use for various practical applications, both for obtaining new materials e.g. optical fibers and for replacing systems based on toxic lead silicate. Information on vaporization processes and thermodynamic properties obtained in the present study will be useful for the development of synthesis methods and approaches for modeling the thermodynamic properties of materials based on this system...
October 14, 2016: Rapid Communications in Mass Spectrometry: RCM
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