11 research outputs found

    Determination of Radiation Attenuation Coefficients of Concretes in Different Densities

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    The density of the concrete is important parameter for different properties. Using different types and rates of aggregates cause different densities of the concretes. Radiation shielding properties can be varied with the density and it is important to obtain optimum density for this purpose. In this study radiation attenuation coefficients were measured by comparison of five different densities of concrete that called lightweight, semi-lightweight, ordinary and semi-heavyweight and heavyweight. For this purpose concretes were produced with suitable aggregate in laboratory conditions and determined some physical and mechanical properties. The total linear attenuation coefficient measurements have been obtained by a collimated beam of gamma ray from sources ^{60}Co

    Cement Paste as a Radiation Shielding Material

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    Cement, mainly, natural limestone and clay mixture after being heated at high temperature is obtained by milling and it is defined as a hydraulic binder material. Especially, cement is used in production concrete. The photon attenuation coefficient (μ, cm1cm^{-1}) for cement paste has been measured using gamma spectrometer containing NaI(Tl) detector and MCA at 835, 1173, and 1332 keV. Cement paste was prepared with types of Portland cement which is CEM I 52,5 R- and CEN reference sand has been used according to TS EN 196-1 standard. The mass attenuation coefficients have been calculated at photon energies of 1 keV to 100 GeV using XCOM and the obtained results were compared with the measurements at 835, 1173, and 1332 keV

    Determination of Some Heavyweight Aggregate Half Value Layer Thickness Used for Radiation Shielding

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    A radiation dose above the maximum permissible limit is very dangerous for human being. In radiation shielding, absorbent materials' properties must be well known. Heavyweight concrete is the most widely used in the world for this aim. The aggregate component of concrete plays an important role in improving concrete properties and this is effect of shielding properties of concrete. The thickness of any given material where 50% of the incident energy has been attenuated is known as the half-value layer. The half-value layer is expressed in units of distance (mm or cm). Like the attenuation coefficient, it is photon energy dependent. Increase of the penetrating energy of a stream of photons will result in an increase in a material's half-value layer. In this study, half-value layer thickness of concrete containing limonite, siderite and barite at different ratios was investigated; for this purpose measurements have been obtained by a collimated beam of gamma ray from sources 60Co\text{}^{60}Co. The total linear attenuation coefficient (μ), half-value layer thickness is evaluated in this study

    Sleep disturbances in patients with lung cancer in Turkey.

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    INTRODUCTION: Sleep quality is known to be associated with the distressing symptoms of cancer. The purpose of this study was to analyze the impact of cancer symptoms on insomnia and the prevalence of sleep-related problems reported by the patients with lung cancer in Turkey. MATERIALS AND METHODS: Assesment of Palliative Care in Lung Cancer in Turkey (ASPECT) study, a prospective multicenter study conducted in Turkey with the participation of 26 centers and included all patients with lung cancer, was re-evaluated in terms of sleep problems, insomnia and possible association with the cancer symptoms. Demographic characteristics of patients and information about disease were recorded for each patient by physicians via face-to-face interviews, and using hospital records. Patients who have difficulty initiating or maintaining sleep (DIMS) is associated with daytime sleepiness/fatigue were diagnosed as having insomnia. Daytime sleepiness, fatigue and lung cancer symptoms were recorded and graded using the Edmonton Symptom Assessment Scale. RESULT: Among 1245 cases, 48.4% reported DIMS, 60.8% reported daytime sleepiness and 82.1% reported fatigue. The prevalence of insomnia was 44.7%. Female gender, patients with stage 3-4 disease, patients with metastases, with comorbidities, and with weight loss > 5 kg had higher rates of insomnia. Also, patients with insomnia had significantly higher rates of pain, nausea, dyspnea, and anxiety. Multivariate logistic regression analysis showed that patients with moderate to severe pain and dyspnea and severe anxiety had 2-3 times higher rates of insomnia. CONCLUSIONS: In conclusion, our results showed a clear association between sleep disturbances and cancer symptoms. Because of that, adequate symptom control is essential to maintain sleep quality in patients with lung cancer

    COVID-19: booster(s) vs. hospitalization and Intensive Care Unit admission

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    OBJECTIVE: As the pandemic continues, different vaccine protocols have been implemented to maintain the protection of vaccines and to provide protection against new variants. The aim of this study was to assess hospitalized patients’ vaccination status and document the efficacy of boosters. PATIENTS AND METHODS: The patients that were hospitalized due to COVID-19 were enrolled from 28 hospitals in Turkey for five months from September 2021. 5,331 confirmed COVID-19 patients from collaborating centers were randomly enrolled to understand/estimate the distribution of vaccination status in hospitalized patients and to compare the efficacy of vaccination/booster protocols. RESULTS: 2,779 men and 2,552 women of which 2,408 (45.2%) were admitted to Intensive Care Units participated in this study. It was found that the highest risk reduction for all age groups was found in groups that received 4 doses. Four doses of vaccination for every 3.7 people under 50 years of age, for every 5.7 people in the 50-64 age group, and for every 4.3 people over 65 years of age will prevent 1 patient from being admitted to intensive care. Regardless of the type of vaccine, it was found that the risk of ICU hospitalization decreased in those who were vaccinated compared to those who were not vaccinated. Regardless of the type of vaccine, the ICU risk was found to decrease 1.25-fold in those who received 1 or 2 doses of vaccine, 1.18-fold in those who received 3 doses, and 3.26-fold in those who received 4 doses. CONCLUSIONS: The results suggested that the addition of a fourth dose is more effective in preventing intensive unit care even in disadvantaged groups

    COVID-19: booster(s) vs. hospitalization and Intensive Care Unit admission.

    No full text
    OBJECTIVE: As the pandemic continues, different vaccine protocols have been implemented to maintain the protection of vaccines and to provide protection against new variants. The aim of this study was to assess hospitalized patients' vaccination status and document the efficacy of boosters. PATIENTS AND METHODS: The patients that were hospitalized due to COVID-19 were enrolled from 28 hospitals in Turkey for five months from September 2021. 5,331 confirmed COVID-19 patients from collaborating centers were randomly enrolled to understand/estimate the distribution of vaccination status in hospitalized patients and to compare the efficacy of vaccination/booster protocols. RESULTS: 2,779 men and 2,552 women of which 2,408 (45.2%) were admitted to Intensive Care Units participated in this study. It was found that the highest risk reduction for all age groups was found in groups that received 4 doses. Four doses of vaccination for every 3.7 people under 50 years of age, for every 5.7 people in the 50-64 age group, and for every 4.3 people over 65 years of age will prevent 1 patient from being admitted to intensive care. Regardless of the type of vaccine, it was found that the risk of ICU hospitalization decreased in those who were vaccinated compared to those who were not vaccinated. Regardless of the type of vaccine, the ICU risk was found to decrease 1.25-fold in those who received 1 or 2 doses of vaccine, 1.18-fold in those who received 3 doses, and 3.26-fold in those who received 4 doses. CONCLUSIONS: The results suggested that the addition of a fourth dose is more effective in preventing intensive unit care even in disadvantaged
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