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https://www.readbyqxmd.com/read/28213626/effectiveness-of-screening-for-craniosynostosis-with-ultrasound-a-retrospective-review
#1
Kent M Hall, David A Besachio, Matthew D Moore, Adrian J Mora, William R Carter
BACKGROUND: Minimizing the ionizing radiation dose to children is fundamental to pediatric radiology. The most widely accepted imaging examination for evaluating craniosynostosis is computed tomography (CT) of the head, an examination that involves ionizing radiation. OBJECTIVE: To determine if sonography of the cranial sutures is an adequate screening examination for the diagnosis of craniosynostosis in patients with abnormal skull shape. MATERIALS AND METHODS: A retrospective review of all cranial suture ultrasound (US) examinations performed during the course of a 3-year period (July 2012 - September 2015) was undertaken...
February 17, 2017: Pediatric Radiology
https://www.readbyqxmd.com/read/28213359/methylation-of-the-phosphatase-transcription-activator-eya1-by-protein-arginine-methyltransferase-1-mechanistic-functional-and-structural-studies
#2
Xingguo Li, Allison Eberhardt, Jeanne N Hansen, Dirk Bohmann, Haitao Li, Nina F Schor
The eyes absent (EYA) family proteins are conserved transcriptional coactivators with intrinsic protein phosphatase activity. They play an essential role in the development of various organs in metazoans. These functions are associated with a unique combination of phosphatase and transactivation activities. However, it remains poorly understood how these activities and the consequent biologic functions of EYA are regulated. Here, we demonstrate that 2 conserved arginine residues, R304 and R306, of EYA1 are essential for its in vitro phosphatase activity and in vivo function during Drosophila eye development...
February 17, 2017: FASEB Journal: Official Publication of the Federation of American Societies for Experimental Biology
https://www.readbyqxmd.com/read/28213175/quantitative-analysis-of-mycosporine-like-amino-acids-in-marine-algae-by-capillary-electrophoresis-with-diode-array-detection
#3
Anja Hartmann, Adele Murauer, Markus Ganzera
Marine species have evolved a variety of physical or chemical strategies to diminish damage from elevated environmental ultraviolet radiation. Mycosporine-like amino acids, a group of widely distributed small water soluble compounds, are biologically relevant because of their photo-protective potential. In addition, presumed antioxidant and skin protective strategies raise the interest for possible medicinal and cosmetic applications. In this study the first CE method for the quantification of mycosporine-like amino acids in marine species is presented...
February 4, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28211708/direct-observation-of-spatiotemporal-dynamics-of-short-electron-bunches-in-storage-rings
#4
C Evain, E Roussel, M Le Parquier, C Szwaj, M-A Tordeux, J-B Brubach, L Manceron, P Roy, S Bielawski
In recent synchrotron radiation facilities, the use of short (picosecond) electron bunches is a powerful method for producing giant pulses of terahertz coherent synchrotron radiation. Here we report on the first direct observation of these pulse shapes with a few picoseconds resolution, and of their dynamics over a long time. We thus confirm in a very direct way the theories predicting an interplay between two physical processes. Below a critical bunch charge, we observe a train of identical THz pulses (a broadband Terahertz comb) stemming from the shortness of the electron bunches...
February 3, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28206757/theoretical-study-on-non-radiative-decay-of-dimethylaminobenzonitrile-through-triplet-state-in-gas-phase-non-polar-and-polar-solutions
#5
Kayo Suda, Daisuke Yokogawa
In the design of bio-imaging molecules, the control of radiative and non-radiative decay is important. Dimethylaminobenzonitrile (DMABN) is a suitable model molecule to study radiative and non-radiative decay processes and has been investigated by theoretical and experimental methods. However, an atomistic understanding of non-radiative decay in solutions remains to be achieved. In this study, we investigated the potential energy surfaces in excited states along the rotation of the dimethylamino group and found that the degeneration between S1 and T1 states is one of the key factors in non-radiative decay in polar solvents...
February 16, 2017: Journal of Physical Chemistry. B
https://www.readbyqxmd.com/read/28205510/controlling-second-harmonic-generation-at-the-nanoscale-with-monolithic-algaas-on-alox-antennas
#6
L Carletti, D Rocco, A Locatelli, C De Angelis, V F Gili, M Ravaro, I Favero, G Leo, M Finazzi, L Ghirardini, M Celebrano, G Marino, A V Zayats
We review recent achievements in the field of nanoscale nonlinear AlGaAs photonics based on all-dielectric optical antennas. After discussing the motivation and main technological challenges for the development of an AlGaAs monolithic platform for χ ((2)) nonlinear nanophotonics, we present numerical and experimental investigations of the second-order nonlinear response and physical reasons for high efficiency of second-order nonlinear interactions in the AlGaAs nano-antennas. In particular, we emphasize the role of the dipolar resonances at the fundamental frequency and the multipolar resonances at the second harmonic wavelength...
February 16, 2017: Nanotechnology
https://www.readbyqxmd.com/read/28205452/in-vivo-dosimetry-in-uk-external-beam-radiotherapy-current-and-future-usage
#7
Niall D MacDougall, Michael Graveling, Vibeke N Hansen, Kevin Brownsword, Andrew Morgan
OBJECTIVES: Towards Safer Radiotherapy (1) recommended that radiotherapy centres should have protocols in place for in vivo dosimetry (IVD) monitoring at the beginning of patient treatment courses. This report determines IVD implementation in the UK in 2014, the methods used and makes recommendations on future use. METHODS: Evidence from peer-reviewed journals was used in conjunction with the first survey of UK radiotherapy centres' IVD practice since the publication of TSRT...
February 16, 2017: British Journal of Radiology
https://www.readbyqxmd.com/read/28205026/common-strategic-research-agenda-for-radiation-protection-in-medicine
#8
(no author information available yet)
: Reflecting the change in funding strategies for European research projects, and the goal to jointly improve medical radiation protection through sustainable research efforts, five medical societies involved in the application of ionising radiation (European Association of Nuclear Medicine, EANM; European Federation of Organizations for Medical Physics. EFOMP; European Federation of Radiographer Societies, EFRS; European Society of Radiology, ESR; European Society for Radiotherapy and Oncology, ESTRO) have identified research areas of common interest and developed this first edition of the Common Strategic Research Agenda (SRA) for medical radiation protection...
February 15, 2017: Insights Into Imaging
https://www.readbyqxmd.com/read/28199840/citron-kinase-deficiency-leads-to-chromosomal-instability-and-tp53-sensitive-microcephaly
#9
Federico Tommaso Bianchi, Chiara Tocco, Gianmarco Pallavicini, Yifan Liu, Fiammetta Vernì, Chiara Merigliano, Silvia Bonaccorsi, Nadia El-Assawy, Lorenzo Priano, Marta Gai, Gaia Elena Berto, Alessandra Maria Adelaide Chiotto, Francesco Sgrò, Alessia Caramello, Laura Tasca, Ugo Ala, Francesco Neri, Salvatore Oliviero, Alessandro Mauro, Stephan Geley, Maurizio Gatti, Ferdinando Di Cunto
Mutations in citron (CIT), leading to loss or inactivation of the citron kinase protein (CITK), cause primary microcephaly in humans and rodents, associated with cytokinesis failure and apoptosis in neural progenitors. We show that CITK loss induces DNA damage accumulation and chromosomal instability in both mammals and Drosophila. CITK-deficient cells display "spontaneous" DNA damage, increased sensitivity to ionizing radiation, and defective recovery from radiation-induced DNA lesions. In CITK-deficient cells, DNA double-strand breaks increase independently of cytokinesis failure...
February 14, 2017: Cell Reports
https://www.readbyqxmd.com/read/28198467/study-of-radiative-heat-transfer-in-%C3%A3-ngstr%C3%A3-m-and-nanometre-sized-gaps
#10
Longji Cui, Wonho Jeong, Víctor Fernández-Hurtado, Johannes Feist, Francisco J García-Vidal, Juan Carlos Cuevas, Edgar Meyhofer, Pramod Reddy
Radiative heat transfer in Ångström- and nanometre-sized gaps is of great interest because of both its technological importance and open questions regarding the physics of energy transfer in this regime. Here we report studies of radiative heat transfer in few Å to 5 nm gap sizes, performed under ultrahigh vacuum conditions between a Au-coated probe featuring embedded nanoscale thermocouples and a heated planar Au substrate that were both subjected to various surface-cleaning procedures. By drawing on the apparent tunnelling barrier height as a signature of cleanliness, we found that upon systematically cleaning via a plasma or locally pushing the tip into the substrate by a few nanometres, the observed radiative conductances decreased from unexpectedly large values to extremely small ones-below the detection limit of our probe-as expected from our computational results...
February 15, 2017: Nature Communications
https://www.readbyqxmd.com/read/28195077/effects-of-air-pollution-on-the-skin-a-review
#11
REVIEW
Poonam Puri, Shashi Kumar Nandar, Sushruta Kathuria, V Ramesh
The increase in air pollution over the years has had major effects on the human skin. Various air pollutants such as ultraviolet radiation, polycyclic aromatic hydrocarbons, volatile organic compounds, oxides, particulate matter, ozone and cigarette smoke affect the skin as it is the outermost barrier. Air pollutants damage the skin by inducing oxidative stress. Although human skin acts as a biological shield against pro-oxidative chemicals and physical air pollutants, prolonged or repetitive exposure to high levels of these pollutants may have profound negative effects on the skin...
February 7, 2017: Indian Journal of Dermatology, Venereology and Leprology
https://www.readbyqxmd.com/read/28194755/withdrawn-exercise-for-dysmenorrhoea
#12
REVIEW
Julie Brown, Stephen Brown
BACKGROUND: Dysmenorrhoea is characterised by cramping lower abdominal pain that may radiate to the lower back and upper thighs and is commonly associated with nausea, headache, fatigue and diarrhoea. Physical exercise has been suggested as a non-medical approach to the management of these symptoms. OBJECTIVES: To assess the evidence for the effectiveness of exercise in the treatment of dysmenorrhoea. SEARCH METHODS: A search was conducted using the methodology of the Menstrual Disorders and Subfertility Group (August 2009)...
February 14, 2017: Cochrane Database of Systematic Reviews
https://www.readbyqxmd.com/read/28194641/unsupervised-exercise-in-survivors-of-human-papillomavirus-related-head-and-neck-cancer-how-many-can-go-it-alone
#13
Joshua Bauml, Jiyoung Kim, Xiaochen Zhang, Charu Aggarwal, Roger B Cohen, Kathryn Schmitz
PURPOSE: Patients with human papillomavirus (HPV)-related head and neck cancer (HNC) have a better prognosis relative to other types of HNC, making survivorship an emerging and critical issue. Exercise is a core component of survivorship care, but little is known about how many survivors of HPV-related HNC can safely be advised to start exercising on their own, as opposed to needing further evaluation or supervised exercise. METHODS: We utilized guidelines to identify health issues that would indicate value of further evaluation prior to being safely prescribed unsupervised exercise...
February 13, 2017: Journal of Cancer Survivorship: Research and Practice
https://www.readbyqxmd.com/read/28193241/present-state-and-issues-in-iort-physics
#14
REVIEW
Frank W Hensley
Literature was reviewed to assess the physical aspects governing the present and emerging technologies used in intraoperative radiation therapy (IORT). Three major technologies were identified: treatment with electrons, treatment with external generators of kV X-rays and electronic brachytherapy. Although also used in IORT, literature on brachytherapy with radioactive sources is not systematically reviewed since an extensive own body of specialized literature and reviews exists in this field. A comparison with radioactive sources is made in the use of balloon catheters for partial breast irradiation where these are applied in almost an identical applicator technique as used with kV X-ray sources...
January 27, 2017: Radiation Oncology
https://www.readbyqxmd.com/read/28191342/dose-response-curves-of-the-fdxr-and-rad51-genes-with-6-and-18-mv-beam-energies-in-human-peripheral-blood-lymphocytes
#15
Alihossein Saberi, Ehsan Khodamoradi, Mohammad Javad Tahmasebi Birgani, Manoochehr Makvandi, Bijan Noori
BACKGROUND: Rapid dose assessment using biological dosimetry methods is essential to increase the chance of survival of exposed individuals in radiation accidents. OBJECTIVES: We compared the expression levels of the FDXR and RAD51 genes at 6 and 18 MV beam energies in human peripheral blood lymphocytes. The results of our study can be used to analyze radiation energy in biological dosimetry. METHODS: For this in vitro experimental study, from 36 students in the medical physics and virology departments, seven voluntary, healthy, non-smoking male blood donors of Khuzestan ethnicity with no history of exposure to ionization radiation were selected using simple randomized sampling...
November 2016: Iranian Red Crescent Medical Journal
https://www.readbyqxmd.com/read/28190371/occupational-radiation-exposure-of-anesthesia-providers
#16
Rachel R Wang, Amanda H Kumar, Pedro Tanaka, Alex Macario
Anesthesia providers are frequently exposed to radiation during routine patient care in the operating room and remote anesthetizing locations. Eighty-two percent of anesthesiology residents (n = 57 responders) at our institution had a "high" or "very high" concern about the level of ionizing radiation exposure, and 94% indicated interest in educational materials about radiation safety. This article highlights key learning points related to basic physical principles, effects of ionizing radiation, radiation exposure measurement, occupational dose limits, considerations during pregnancy, sources of exposure, factors affecting occupational exposure such as positioning and shielding, and monitoring...
February 1, 2017: Seminars in Cardiothoracic and Vascular Anesthesia
https://www.readbyqxmd.com/read/28186799/superresonant-radiation-stimulated-by-higher-harmonics
#17
Cristian Redondo Lourés, Thomas Roger, Daniele Faccio, Fabio Biancalana
Solitons propagating in media with higher-order dispersion will shed radiation known as resonant radiation, with applications in frequency broadening, deep UV sources for spectroscopy, and fundamental studies of soliton physics. Using a recently proposed equation that models the behavior of ultrashort optical pulses in nonlinear media using the analytic signal, we find that the resonant radiation associated with the third-harmonic generation term of the equation is parametrically stimulated with an unprecedented gain...
January 27, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28186781/accelerating-plasma-mirrors-to-investigate-the-black-hole-information-loss-paradox
#18
Pisin Chen, Gerard Mourou
The question of whether Hawking evaporation violates unitarity, and therefore results in the loss of information, has remained unresolved since Hawking's seminal discovery. To date, the investigations have remained mostly theoretical since it is almost impossible to settle this paradox through direct astrophysical black hole observations. Here, we point out that relativistic plasma mirrors can be accelerated drastically and stopped abruptly by impinging intense x-ray pulses on solid plasma targets with a density gradient...
January 27, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28181480/a-comparison-between-track-structure-condensed-history-monte-carlo-simulations-and-mird-cellular-s-values
#19
M A Tajik-Mansoury, H Rajabi, H Mozdarani
The S-value is a standard measure in cellular dosimetry. S-values are calculated by applying analytical methods or by Monte Carlo simulation. In Monte Carlo simulation, particles are either tracked individually event-by-event or close events are condensed and processed collectively in different steps. Both of these methods have been employed for estimation of cellular S-values, but there is no consistency between the published results. In the present paper, we used the Geant4-DNA track-structure physics model as the reference to estimate the cellular S-values...
March 7, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28180988/internal-exposure-to-neutron-activated-56-mn-dioxide-powder-in-wistar-rats-part%C3%A2-2-pathological-effects
#20
Kazuko Shichijo, Nariaki Fujimoto, Darkhan Uzbekov, Ynkar Kairkhanova, Aisulu Saimova, Nailya Chaizhunusova, Nurlan Sayakenov, Dariya Shabdarbaeva, Nurlan Aukenov, Almas Azimkhanov, Alexander Kolbayenkov, Zhanna Mussazhanova, Daisuke Niino, Masahiro Nakashima, Kassym Zhumadilov, Valeriy Stepanenko, Masao Tomonaga, Tolebay Rakhypbekov, Masaharu Hoshi
To fully understand the radiation effects of the atomic bombing of Hiroshima and Nagasaki among the survivors, radiation from neutron-induced radioisotopes in soil and other materials should be considered in addition to the initial radiation directly received from the bombs. This might be important for evaluating the radiation risks to the people who moved to these cities soon after the detonations and probably inhaled activated radioactive "dust." Manganese-56 is known to be one of the dominant radioisotopes produced in soil by neutrons...
February 8, 2017: Radiation and Environmental Biophysics
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