The Experts below are selected from a list of 5532 Experts worldwide ranked by ideXlab platform
Tetsuo Sasaki - One of the best experts on this subject based on the ideXlab platform.
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terahertz fingerprints of short range correlations of disordered atoms in diflunisal
Journal of Physical Chemistry A, 2019Co-Authors: Feng Zhang, Houngwei Wang, Keisuke Tominaga, M Hayashi, Tetsuo SasakiAbstract:This work proposes a terahertz (THz) spectroscopy approach to the investigation of one of the outstanding problems in crystallography-the structure analysis of a crystal with disorder. Form I of diflunisal, in which the two ortho sites on one phenyl ring of diflunisal show occupational disorder, was used for an illustration. THz Radiation Interacts with the collective vibrations of correlated disorder, thus providing a promising tool to examine the symmetry of short-range correlations of disordered atoms. Through a thorough examination of the selection rule of THz vibrations in which the disordered atoms are involved to different extents, we deduced that only four short-range correlation possibilities of disorder exist and all of them display unambiguous fingerprint peaks in the 50-170 cm-1 frequency region. We finally proposed an alternating packing model in which the correlation lengths of disorder are on the nanometer scale.
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Terahertz Fingerprints of Short-Range Correlations of Disordered Atoms in Diflunisal
2019Co-Authors: Feng Zhang, Houngwei Wang, Keisuke Tominaga, M Hayashi, Tetsuo SasakiAbstract:This work proposes a terahertz (THz) spectroscopy approach to the investigation of one of the outstanding problems in crystallographythe structure analysis of a crystal with disorder. Form I of diflunisal, in which the two ortho sites on one phenyl ring of diflunisal show occupational disorder, was used for an illustration. THz Radiation Interacts with the collective vibrations of correlated disorder, thus providing a promising tool to examine the symmetry of short-range correlations of disordered atoms. Through a thorough examination of the selection rule of THz vibrations in which the disordered atoms are involved to different extents, we deduced that only four short-range correlation possibilities of disorder exist and all of them display unambiguous fingerprint peaks in the 50–170 cm–1 frequency region. We finally proposed an alternating packing model in which the correlation lengths of disorder are on the nanometer scale
Feng Zhang - One of the best experts on this subject based on the ideXlab platform.
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terahertz fingerprints of short range correlations of disordered atoms in diflunisal
Journal of Physical Chemistry A, 2019Co-Authors: Feng Zhang, Houngwei Wang, Keisuke Tominaga, M Hayashi, Tetsuo SasakiAbstract:This work proposes a terahertz (THz) spectroscopy approach to the investigation of one of the outstanding problems in crystallography-the structure analysis of a crystal with disorder. Form I of diflunisal, in which the two ortho sites on one phenyl ring of diflunisal show occupational disorder, was used for an illustration. THz Radiation Interacts with the collective vibrations of correlated disorder, thus providing a promising tool to examine the symmetry of short-range correlations of disordered atoms. Through a thorough examination of the selection rule of THz vibrations in which the disordered atoms are involved to different extents, we deduced that only four short-range correlation possibilities of disorder exist and all of them display unambiguous fingerprint peaks in the 50-170 cm-1 frequency region. We finally proposed an alternating packing model in which the correlation lengths of disorder are on the nanometer scale.
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Terahertz Fingerprints of Short-Range Correlations of Disordered Atoms in Diflunisal
2019Co-Authors: Feng Zhang, Houngwei Wang, Keisuke Tominaga, M Hayashi, Tetsuo SasakiAbstract:This work proposes a terahertz (THz) spectroscopy approach to the investigation of one of the outstanding problems in crystallographythe structure analysis of a crystal with disorder. Form I of diflunisal, in which the two ortho sites on one phenyl ring of diflunisal show occupational disorder, was used for an illustration. THz Radiation Interacts with the collective vibrations of correlated disorder, thus providing a promising tool to examine the symmetry of short-range correlations of disordered atoms. Through a thorough examination of the selection rule of THz vibrations in which the disordered atoms are involved to different extents, we deduced that only four short-range correlation possibilities of disorder exist and all of them display unambiguous fingerprint peaks in the 50–170 cm–1 frequency region. We finally proposed an alternating packing model in which the correlation lengths of disorder are on the nanometer scale
Ramos-mendez J. - One of the best experts on this subject based on the ideXlab platform.
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A new standard DNA damage (SDD) data format
'Radiation Research Society', 2020Co-Authors: Schuemann J., Ingram S., Paganetti H., Mcnamara A. L., Warmenhoven J. W., Henthorn N. T., Kirkby K. J., Merchant M. J., Held K. D., Ramos-mendez J.Abstract:Sem informaçãoOur understanding of Radiation-induced cellular damage has greatly improved over the past few decades. Despite this progress, there are still many obstacles to fully understand how Radiation Interacts with biologically relevant cellular components, such as DNA, to cause observable end points such as cell killing. Damage in DNA is identified as a major route of cell killing. One hurdle when modeling biological effects is the difficulty in directly comparing results generated by members of different research groups. Multiple Monte Carlo codes have been developed to simulate damage induction at the DNA scale, while at the same time various groups have developed models that describe DNA repair processes with varying levels of detail. These repair models are intrinsically linked to the damage model employed in their development, making it difficult to disentangle systematic effects in either part of the modeling chain. These modeling chains typically consist of track-structure Monte Carlo simulations of the physical interactions creating direct damages to DNA, followed by simulations of the production and initial reactions of chemical species causing so-called ''indirect'' damages. After the induction of DNA damage, DNA repair models combine the simulated damage patterns with biological models to determine the biological consequences of the damage. To date, the effect of the environment, such as molecular oxygen (normoxic vs. hypoxic), has been poorly considered. We propose a new standard DNA damage (SDD) data format to unify the interface between the simulation of damage induction in DNA and the biological modeling of DNA repair processes, and introduce the effect of the environment (molecular oxygen or other compounds) as a flexible parameter. Such a standard greatly facilitates inter-model comparisons, providing an ideal environment to tease out model assumptions and identify persistent, underlying mechanisms. Through inter-model comparisons, this unified standard has the potential to greatly advance our understanding of the underlying mechanisms of Radiation-induced DNA damage and the resulting observable biological effects when Radiation parameters and/or environmental conditions change.19117692Sem informaçãoSem informaçãoSem informaçãoWe acknowledge support from the STFC-funded Global Challenge Networkthorn in Advanced Radiotherapy Multi-Scale Monte Carlo Modeling for Radiotherapy Sandpit (no. ST/N002423/1 to JS, ALM, JWW, NTH, KK, MJM and SJM). We also acknowledge support from the NIH/NCI [grant no. R01CA187003 ("TOPAS-nBio: a Monte Carlo tool for Radiation biology research'') to JS] and NASA contract NNJ15HK11 to IP
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A New Standard DNA Damage (SDD) Data Format
'Radiation Research Society', 2019Co-Authors: Schuemann J., Mcnamara A.l., Warmenhoven J.w., Henthorn N.t., Kirkby K.j., Merchant M.j., Ingram S., Paganetti H., Held K.d., Ramos-mendez J.Abstract:International audienceOur understanding of Radiation-induced cellular damage has greatly improved over the past few decades. Despite this progress, there are still many obstacles to fully understand how Radiation Interacts with biologically relevant cellular components, such as DNA, to cause observable end points such as cell killing. Damage in DNA is identified as a major route of cell killing. One hurdle when modeling biological effects is the difficulty in directly comparing results generated by members of different research groups. Multiple Monte Carlo codes have been developed to simulate damage induction at the DNA scale, while at the same time various groups have developed models that describe DNA repair processes with varying levels of detail. These repair models are intrinsically linked to the damage model employed in their development, making it difficult to disentangle systematic effects in either part of the modeling chain. These modeling chains typically consist of track-structure Monte Carlo simulations of the physical interactions creating direct damages to DNA, followed by simulations of the production and initial reactions of chemical species causing so-called “indirect” damages. After the induction of DNA damage, DNA repair models combine the simulated damage patterns with biological models to determine the biological consequences of the damage. To date, the effect of the environment, such as molecular oxygen (normoxic vs. hypoxic), has been poorly considered. We propose a new standard DNA damage (SDD) data format to unify the interface between the simulation of damage induction in DNA and the biological modeling of DNA repair processes, and introduce the effect of the environment (molecular oxygen or other compounds) as a flexible parameter. Such a standard greatly facilitates inter-model comparisons, providing an ideal environment to tease out model assumptions and identify persistent, underlying mechanisms. Through inter-model comparisons, this unified standard has the potential to greatly advance our understanding of the underlying mechanisms of Radiation-induced DNA damage and the resulting observable biological effects when Radiation parameters and/or environmental conditions change
Frank Seebacher - One of the best experts on this subject based on the ideXlab platform.
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uv b Radiation Interacts with temperature to determine animal performance
Functional Ecology, 2016Co-Authors: Ensiyeh Ghanizadeh Kazerouni, Craig E Franklin, Frank SeebacherAbstract:Summary The interaction between UV-B and temperature can modify the effects of climate variability on animal function because UV-B and increasing temperatures may increase reactive oxygen species (ROS) production and thereby impair animal performance. However, antioxidant enzyme activities are also increased at higher temperatures, which could counteract negative effects of increased ROS. Conversely, UV-B exposure at lower temperature can exacerbate the effects of ROS because of lower antioxidant enzyme activities. Phenotypes can be plastic to compensate for potentially negative environmental effects. Plasticity may be induced by conditions experienced during pre- or early post-zygotic development, and it may occur reversibly within adult organisms (acclimation). Developmental plasticity and acclimation may interact to determine phenotypes in variable environments. Here, we tested the hypothesis that increased antioxidant enzyme activities are insufficient to alleviate the interactive effects of UV-B and increased temperature on mosquitofish (Gambusia holbrooki). Additionally, we tested whether developmental conditions influenced the capacity for acclimation to UV-B and temperature so that cohorts born in summer at high UV-B and temperature conditions are better able to compensate for ROS damage compared to cohorts born in winter. We exposed mosquitofish to UV-B and control (no-UV-B) at different acclimation temperatures (18, 28 and 32 °C), and measured responses acutely at 18, 28 and 32 °C in a fully factorial design. In fish born in summer, UV-B had significant negative effects on swimming performance and resting metabolic rate at both low (18 °C) and high (32 °C) acclimation temperatures, which were accompanied by higher ROS-induced damage. At their average temperature experienced naturally (28 °C), fish born in summer were not affected by UV-B and showed lower damage and higher antioxidant enzyme activities compared to the other acclimation temperatures. In contrast, swimming performance of winter-caught fish was negatively affected by UV-B at all acclimation temperatures, which was paralleled by higher ROS-induced damage and antioxidant enzyme activities that did not acclimate. However, metabolic scope was not reduced by UV-B or temperature in any of the cohorts. Our results showed that developmental conditions modify the capacity for acclimation later in life, and that the interaction between developmental and acclimation conditions can increase the resilience of animals to environmental variability. These results have important implications for understanding the evolution of acclimation, and for predictions of how climate change affects animal performance.
Stephen Barnard - One of the best experts on this subject based on the ideXlab platform.
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sensitivity and latency of ionising Radiation induced cataract
Experimental Eye Research, 2021Co-Authors: Elizabeth A Ainsbury, Stephen BarnardAbstract:Abstract When managed with appropriate Radiation protection procedures, ionising Radiation is of great benefit to society. Opacification of the lens, and vision impairing cataract, have recently been recognised at potential effects of relatively low dose Radiation exposure, on the order of 1 Gy or below. Within the last 10 years, understanding of the effects of low dose ionising Radiation on the lens has increased, particularly in terms of DNA damage and responses, and how multiple Radiation or other events in the lens might contribute to the overall risk of cataract. However, gaps remain, not least in the understanding of how Radiation Interacts with other risk factors such as aging, as well as the relative radiosensitivity of the lens compared to tissues of the body. This paper reviews the current literature in the field of low dose Radiation cataract, with a particular focus on sensitivity and latency.