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Leading four generations at work

M Reynolds, B Fallone
PURPOSE: The impact of magnetic fields on the readings of a linac monitor chamber have not yet been investigated. Herein we examine the total dose response as well as any deviations in the beam parameters of flatness and symmetry when a Varian monitor chamber is irradiated within an applied magnetic field. This work has direct application to the development of Linac-MR systems worldwide. METHODS: A Varian monitor chamber was modeled in the Monte Carlo code PENELOPE and irradiated in the presence of a magnetic field with a phase space generated from a model of a Linac-MR prototype system...
June 2016: Medical Physics
Kenneth I Brown, Elizabeth R Williams, Felipe de Carvalho, Stuart N Baker
Previous work showed that repetitive peripheral nerve stimulation can induce plastic changes in motor cortical output. Triggering electrical stimulation of central structures from natural activity can also generate plasticity. In this study, we tested whether triggering peripheral nerve stimulation from muscle activity would likewise induce changes in motor output. We developed a wearable electronic device capable of recording electromyogram (EMG) and delivering electrical stimulation under closed-loop control...
2016: Frontiers in Human Neuroscience
M Morrocchi, W C J Hunter, A Del Guerra, T K Lewellen, P E Kinahan, L R MacDonald, M G Bisogni, R S Miyaoka
A PET detector featuring a pseudo-monolithic crystal is being developed as a more cost-effective alternative to a full monolithic crystal PET detector. This work evaluates different methods to localize the scintillation events in quartered monolithic crystals that are optically coupled. A semi-monolithic crystal assembly was formed using four 26  ×  26  ×  10 mm(3) LYSO crystals optically coupled together using optical adhesive, to mimic a 52  ×  52  ×  10 mm(3) monolithic crystal detector...
December 7, 2016: Physics in Medicine and Biology
Carola Schultz, Sven Vedder, Martin Winter, Sascha Nowak
The development of a novel high performance liquid chromatography (HPLC) method hyphenated to an ion-trap time-of-flight mass spectrometer (IT-TOF-MS) for the separation and identification of constituents from common organic carbonate solvent-based electrolyte systems in lithium ion batteries (LIBs) is presented in this work. The method development was conducted for the qualitative structural elucidation of electrolyte main constituents with a special focus on the aging products of these components. The determination of their limits of detection was performed as well...
November 15, 2016: Analytical Chemistry
Kathryn Atwell, Sara-Jane Dunn, James M Osborne, Hillel Kugler, E Jane Albert Hubbard
Computational models are an invaluable tool in modern biology. They provide a framework within which to summarize existing knowledge, enable competing hypotheses to be compared qualitatively and quantitatively, and to facilitate the interpretation of complex data. Moreover, models allow questions to be investigated that are difficult to approach experimentally. Theories can be tested in context, identifying the gaps in our understanding and potentially leading to new hypotheses. Models can be developed on a variety of scales and with different levels of mechanistic detail, depending on the available data, the biological questions of interest, and the available mathematical and computational tools...
November 2016: Molecular Reproduction and Development
Marco Oberscheider, Patrick Hirsch
BACKGROUND: Efficient transport of non-emergency patients is crucial for ambulance service providers to cope with increased demand resulting from aging Western societies. This paper deals with the optimization of the patient transport operations of the Red Cross of Lower Austria, which is the main provider in this state. Different quality levels of the provided service - expressed by time windows, feasible maximum ride times and exclusive transports - are tested and analyzed on real-life instances to show daily impacts on the provider's resources...
2016: BMC Health Services Research
Alix Chadwell, Laurence Kenney, Sibylle Thies, Adam Galpin, John Head
Users of myoelectric prostheses can often find them difficult to control. This can lead to passive-use of the device or total rejection, which can have detrimental effects on the contralateral limb due to overuse. Current clinically available prostheses are "open loop" systems, and although considerable effort has been focused on developing biofeedback to "close the loop," there is evidence from laboratory-based studies that other factors, notably improving predictability of response, may be as, if not more, important...
2016: Frontiers in Neurorobotics
Kenneth Tran, June-Chiew Han, Andrew J Taberner, Carolyn J Barrett, Edmund J Crampin, Denis S Loiselle
Salt-induced hypertension leads to development of left ventricular hypertrophy in the Dahl salt-sensitive (Dahl/SS) rat. Before progression to left ventricular failure, the heart initially undergoes a compensated hypertrophic response. We hypothesized that changes in myocardial energetics may be an early indicator of transition to failure. Dahl/SS rats and their salt-resistant consomic controls (SS-13(BN)) were placed on either a low- or high-salt diet to generate four cohorts: Dahl-SS rats on a low- (Dahl-LS) or high-salt diet (Dahl-HS), and SS-13(BN) rats on a low- (SSBN-LS) or high-salt diet (SSBN-HS)...
September 1, 2016: American Journal of Physiology. Heart and Circulatory Physiology
Barbara Di Camillo, Azzurra Carlon, Federica Eduati, Gianna Maria Toffolo
BACKGROUND: The insulin signalling pathway (ISP) is an important biochemical pathway, which regulates some fundamental biological functions such as glucose and lipid metabolism, protein synthesis, cell proliferation, cell differentiation and apoptosis. In the last years, different mathematical models based on ordinary differential equations have been proposed in the literature to describe specific features of the ISP, thus providing a description of the behaviour of the system and its emerging properties...
2016: BMC Systems Biology
Feng Zhang, Yang Liu, Hengdong Zhang, Yonghong Ban, Jianfeng Wang, Jian Liu, Lixing Zhong, Xianwen Chen, Baoli Zhu
Lead pollution incidents have occurred frequently in mainland China, which has caused many lead poisoning incidents. This paper took a battery recycling factory as the subject, and focused on measuring the blood lead levels of environmental samples and all the children living around the factory, and analyzed the relationship between them. We collected blood samples from the surrounding residential area, as well as soil, water, vegetables. The atomic absorption method was applied to measure the lead content in these samples...
2016: International Journal of Environmental Research and Public Health
Jiajia Wu, Bin Gao, Shunyi Zhu
The emergence and rapid spread of multiresistant bacteria has lead to an urgent need for novel antimicrobials. Based on single-point substitutions, we generated a series of mutants of micasin, a dermatophytic defensin, with enhanced activities against multiple clinical isolates of Staphylococcus species, including 4 antibiotic-resistant strains. We first mapped the functional surface of micasin by alanine-scanning mutational analysis of its highly exposed residues, through which we found that substitution of site 8 (acidic Glu) dramatically enhanced bacterial killing of this peptide...
July 2016: FASEB Journal: Official Publication of the Federation of American Societies for Experimental Biology
Corey J Bishop, Rebecca L Majewski, Toni-Rose M Guiriba, David R Wilson, Nupura S Bhise, Alfredo Quiñones-Hinojosa, Jordan J Green
UNLABELLED: Non-viral, biomaterial-mediated gene delivery has the potential to treat many diseases, but is limited by low efficacy. Elucidating the bottlenecks of plasmid mass transfer can enable an improved understanding of biomaterial structure-function relationships, leading to next-generation rationally designed non-viral gene delivery vectors. As proof of principle, we transfected human primary glioblastoma cells using a poly(beta-amino ester) complexed with eGFP plasmid DNA. The polyplexes transfected 70...
June 2016: Acta Biomaterialia
Joseph Low, Marc Serfaty, Sarah Davis, Victoria Vickerstaff, Anna Gola, Rumana Z Omar, Michael King, Adrian Tookman, Janet St John Austen, Karen Turner, Louise Jones
BACKGROUND: One-third of people with cancer experience psychological distress and may suppress distressing thoughts, emotions, and concerns, leading to further problems. Conventional psychological treatments reduce distress by problem solving, but in advanced cancer, when ill health is progressive and death may be approaching, physical and psychological difficulties are complex and have no simple solutions. Acceptance and Commitment Therapy encourages acknowledgement and acceptance of mental experiences, increasing people's ability to work with problems that cannot be solved...
February 11, 2016: Trials
Vithiyanjali Sothilingam, Stylianos Michalakis, Marina Garcia Garrido, Martin Biel, Naoyuki Tanimoto, Mathias W Seeliger
PURPOSE: Vision originates in rods and cones at the outer retina. Already at these early stages, diverse processing schemes shape and enhance image information to permit perception over a wide range of lighting conditions. In this work, we address the role of hyperpolarization-activated and cyclic nucleotide-gated channels 1 (HCN1) in rod photoreceptors for the enhancement of rod system responsivity under conditions of light exposure. METHODS: To isolate HCN1 channel actions in rod system responses, we generated double mutant mice by crossbreeding Hcn1-/- mice with Cnga3-/- mice in which cones are non-functional...
2016: PloS One
Juan Diego Azcona, Benigno Barbés, Lilie Wang, Javier Burguete
This paper presents a method to obtain the pencil-beam kernels that characterize a megavoltage photon beam generated in a flattening filter free (FFF) linear accelerator (linac) by deconvolution from experimental measurements at different depths. The formalism is applied to perform independent dose calculations in modulated fields. In our previous work a formalism was developed for ideal flat fluences exiting the linac's head. That framework could not deal with spatially varying energy fluences, so any deviation from the ideal flat fluence was treated as a perturbation...
January 7, 2016: Physics in Medicine and Biology
Damalie Nakanjako, Elizabeth Namagala, Aggrey Semeere, Joanitor Kigozi, Joseph Sempa, John Bosco Ddamulira, Achilles Katamba, Sam Biraro, Sarah Naikoba, Yohana Mashalla, Carey Farquhar, Nelson Sewankambo
INTRODUCTION: Due to a limited health workforce, many health care providers in Africa must take on health leadership roles with minimal formal training in leadership. Hence, the need to equip health care providers with practical skills required to lead high-impact health care programs. In Uganda, the Afya Bora Global Health Leadership Fellowship is implemented through the Makerere University College of Health Sciences (MakCHS) and her partner institutions. Lessons learned from the program, presented in this paper, may guide development of in-service training opportunities to enhance leadership skills of health workers in resource-limited settings...
November 18, 2015: Human Resources for Health
Gerald Gartlehner, Barbara Nussbaumer, Bradley N Gaynes, Catherine A Forneris, Laura C Morgan, Angela Kaminski-Hartenthaler, Amy Greenblatt, Jörg Wipplinger, Linda J Lux, Jeffrey H Sonis, Julia Hofmann, Megan G Van Noord, Dietmar Winkler
BACKGROUND: Seasonal affective disorder (SAD) is a seasonal pattern of recurrent major depressive episodes that most commonly occurs during autumn or winter and remits in spring. The prevalence of SAD ranges from 1.5% to 9%, depending on latitude. The predictable seasonal aspect of SAD provides a promising opportunity for prevention. This review - one of four reviews on efficacy and safety of interventions to prevent SAD - focuses on second-generation antidepressants (SGAs). OBJECTIVES: To assess the efficacy and safety of second-generation antidepressants (in comparison with other SGAs, placebo, light therapy, melatonin or agomelatine, psychological therapies or lifestyle interventions) in preventing SAD and improving patient-centred outcomes among adults with a history of SAD...
2015: Cochrane Database of Systematic Reviews
Robin Otchwemah, Volker Grams, Thorsten Tjardes, Sven Shafizadeh, Holger Bäthis, Marc Maegele, Sabine Messler, Bertil Bouillon, Christian Probst
INTRODUCTION: The bacterial contamination of soft tissues and bone in open fractures leads to an infection rate of up to 50%. Pathogens and their resistance against therapeutic agents change with time and vary in different regions. In this work, our aims were to characterize the bacterial spectrum present in open fractures, analyze the bacterial resistance to antibiotic agents and question the EAST guideline recommendations for antibiotic prophylaxis after open fractures in a German Trauma Network...
October 2015: Injury
Nobuaki Shono, Jun-ichirou Ohzeki, Koichiro Otake, Nuno M C Martins, Takahiro Nagase, Hiroshi Kimura, Vladimir Larionov, William C Earnshaw, Hiroshi Masumoto
Although it is generally accepted that chromatin containing the histone H3 variant CENP-A is an epigenetic mark maintaining centromere identity, the pathways leading to the formation and maintenance of centromere chromatin remain unclear. We previously generated human artificial chromosomes (HACs) whose centromeres contain a synthetic alpha-satellite (alphoid) DNA array containing the tetracycline operator (alphoid(tetO)). We also obtained cell lines bearing the alphoid(tetO) array at ectopic integration sites on chromosomal arms...
December 15, 2015: Journal of Cell Science
Daniel Nieto, Justo Arines, Gerard M O'Connor, María Teresa Flores-Arias
In this work, we report a comparative study of the laser ablation threshold of borosilicate, fused silica, sapphire, and soda-lime glass as a function of the pulse width and for IR laser wavelengths. We determine the ablation threshold for three different pulse durations: τ=500  fs, 10 ps, and 20 ns. Experiments have been performed using a single laser pulse per shot in an ambient (air) environment. The results show a significant difference, of two orders of magnitude, between the group of ablation thresholds obtained for femtosecond, picosecond, and nanosecond pulses...
October 10, 2015: Applied Optics
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