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1.
Appl Radiat Isot ; 181: 110066, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34968881

RESUMO

The purpose of this study was to investigate the x-ray energy dependence of the measured response of detectors (TLD-100) and to estimate the accurate dose delivered to patients during routine X-ray examinations. The response of thermoluminescent dosimeters TLD as a function of low energy range was determined using the X-ray tube at the Ionizing Radiation Met. Lab in the National Institute of Standards, (Secondary Standard Dosimetry Lab (SSLD) Cairo, Egypt. The X-ray dose was measured at 25, 50 and 100 kVp nominal x-ray energies. TLD-100 linearity, reproducibility and relative sensitivity were studied. Several sets of TLD-100 were to different x-ray beam energy to determine the calibration coefficient of the TLD system and the correction factors applied for the dose calculation (readings (nC)/radiation dose (mGy)) was determined in the dose range (0.69 mGy to 350 mGy). The radiation dose to the patient was estimated in diagnostic radiology for the existing working protocols (skull, pelvis, abdomen, and lumbar Spine). TLD-100 was exposed at various nominal energy used for diagnostic (40-100 kVp) and various tube current (50-120 mA) which is normally used in clinical X-ray examinations. The TLD-100 was exposed three times for each kVp value, and the exposure doses were measured in mGy. The obtained results showed a linear behavior of the TLD-100 response as a function of X-ray dose with estimated uncertainty within 10%. This indicates a good accuracy when assessing the entrance dose in diagnostic radiology procedures). The sensitivity of the TLD cards showed a standard deviation of 4.7%. Moreover, the dose-nC factor has the same value (within the standard uncertainty). Mean Entrance Skin Dose for skull, pelvis, abdomen, and lumbar spine were 0.46 ± 0.01, 1.5 ± 0.05, 7.3 ± 0.21 and 9.2 ± 0.29 mGy respectively. The obtained results reflect the agreement with the recommended values and will be useful for the formulation of national reference levels as recommended by the International Atomic Energy Agency (IAEA) SAFETY STANDARDS SERIES No. GSR Part 3 2014.


Assuntos
Radiografia , Dosimetria Termoluminescente/métodos , Abdome/diagnóstico por imagem , Calibragem , Egito , Humanos , Vértebras Lombares/diagnóstico por imagem , Pelve/diagnóstico por imagem , Valores de Referência , Reprodutibilidade dos Testes , Crânio/diagnóstico por imagem , Raios X
2.
J Environ Radioact ; 234: 106632, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33962220

RESUMO

The transfer of 137Cs and 85Sr from soil to different plants has been studied in two successive pot field-grown experiments. Five plant species (Oryza Sativa, Tritichum Vulgares, Vicia Faba, Sesamum Orientale and Trifolium Alexandrinum) were grown in pots with sandy clay loam soil contaminated with varying amounts of 137Cs or 85Sr. The absorption of the radioisotopes was measured in different parts of the plants and their activity concentration was significantly increased with increasing radioactivity of both radioisotopes in the soil. The distribution pattern of the total absorbed 137Cs or 85Sr in different plants after soil contamination shows that the shoots of these plants contained the highest percentage of both radionuclides (65.8-73.8% for 137Cs and 77.3-80.7% for 85Sr) followed by roots (16.4-22.4% for 137Cs and 19.5-21.4% for 85Sr) and finally by grains/seeds (4.9-12.9% for 137Cs and 0.3-1.3% for 85Sr). The transfer factors of 85Sr were higher than those of 137Cs for shoots of the tested plants, and were in the ranges of 2.3×10-2 - 4.8×10-2 and 8.8×10-2 - 2.0×10-1 for 137Cs and 85Sr, respectively. The transfer factors of grains or seeds were significantly lower than those of roots or shoots. Also, the transfer factors of leguminous plants were higher than those of cereal plants. Regarding Trifolium plant, the highest activity concentration of both isotopes was found in the second harvest samples.


Assuntos
Monitoramento de Radiação , Poluentes Radioativos do Solo , Radioisótopos de Césio/análise , Egito , Solo , Poluentes Radioativos do Solo/análise , Radioisótopos de Estrôncio
3.
J Environ Radioact ; 235-236: 106648, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34004546

RESUMO

The transfer of 137Cs and 85Sr from fallout to plants was studied in two successive pot experiments. Five plant species (Oryza Sativa, Tritichum Vulgares, Vicia Faba, Sesamum Orientale and Trifolium Alexandrinum) were grown in pots containing sandy clay loam soil. For simulating foliar contamination, radioactive 137Cs and 85Sr solutions were sprayed once with different activity concentrations gently on the shooting system. After 8 weeks of radioactivity application to the above first four plants and 4 weeks to the last one, the total absorption of 137Cs and 85Sr and their distribution in different parts of the tested plants were determined. Most of the absorbed 137Cs and 85Sr accumulated in shoots with proportions ranged from 70.8 to 81.9% and from 88.9 to 95.0%, respectively for different plants. The absorbed 137Cs and 85Sr by grains/seeds followed that of shoots with values ranged from 11.9 to 19.2% and from 5 to 10.9%, respectively. The percentage of 137Cs absorbed by roots ranged from 6.2 to 10.0% among different plants, while 85Sr in roots of plants was below the minimum detectable activity of the detector. For Trifolium, most of the absorbed 137Cs and 85Sr accumulated in the first harvest (81.9 and 98.6%). The aggregated transfer factors (Tag) of both radionuclides under foliar conditions were to a great extent similar. The average values of Tag factors (m2kg-1) of 137Cs and 85Sr, respectively, in rice grains were 3.4 × 10-4 and 1.6 × 10-4; in wheat grains were 4.2 × 10-4 and 2.1 × 10-4; in bean seeds were 4.9 × 10-4 and 2.6 × 10-4; and in sesame seeds were 2.8 × 10-4 and 1.2 × 10-4. Those Tag factors of grains/seeds were substantially lower than those obtained with straw of the corresponding plant species.


Assuntos
Monitoramento de Radiação , Poluentes Radioativos do Solo , Radioisótopos de Césio/análise , Egito , Poluentes Radioativos do Solo/análise , Radioisótopos de Estrôncio/análise
4.
Hernia ; 25(4): 1027-1034, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33400029

RESUMO

PURPOSE: Enhanced recovery after surgery (ERAS) is a well-known approach to optimize the recovery after surgery. Little is known about specific causes of prolonged hospitalization despite enhanced recovery after open incisional hernia repair (OIHR). The purpose of this study was to identify the causes of continued hospitalization on each of the first 5 postoperative days (PODs) after OIHR. METHODS: This was a retrospective study of consecutive patients undergoing open AWR at a regional academic hernia center from 2008 to 2018. Patient charts were evaluated using predefined potential causes of continued hospitalization on each of the first five PODs. RESULTS: A total of 388 patients (mean age 60.9 years, 54.6% male, mean BMI 27.9 kg/m2) were included in the study. Mesh placement was either preperitoneal/intraperitoneal (20%) or retromuscular (80%) and 61% of the patients had an epidural catheter. The median length of stay (LOS) in the cohort was four [IQR 2-6] days. On PODs 4 and 5, causes of continued hospital stay were absent bowel function (2% on POD 4, 1% on POD 5), pain (7% on POD 3, 2% on POD 4), lack of mobilization (1% on POD 4, 1% on POD 5), and other causes (urinary retention, high drain output, and complications to the surgery). CONCLUSION: Causes for prolonged hospitalization after OIHR were possibly reducible. Future efforts to improve the ERAS regime and reduce LOS after OIHR should focus on pain treatment- and prevention, alternatives to epidural treatment, and well-defined, evidence-based discharge criteria.


Assuntos
Hérnia Ventral , Hérnia Incisional , Feminino , Hérnia Ventral/cirurgia , Herniorrafia/efeitos adversos , Hospitalização , Humanos , Hérnia Incisional/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Telas Cirúrgicas
5.
Radiat Environ Biophys ; 59(4): 743-748, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32676700

RESUMO

Those working in interventional cardiology are exposed to varying radiation doses during diagnostic and interventional procedures. The work presented in this paper aimed to monitor the effective doses received by different categories of medical staff members practicing interventional cardiology procedures including senior cardiologists, junior cardiologists, anesthetists and nurses. Thermo-luminescence dosimeter (TLD) badges that consisted of lithium fluoride doped with magnesium and titanium were used to quantify radiation doses. Measurements were performed with the dosimeters mounted under and above leaded aprons worn by medical staff. The results revealed that the effective doses to senior cardiologists were the highest compared to those to other participating staff members, due to their position close to the X-ray tube. The average daily effective doses for senior cardiologists, junior cardiologists, anesthetists and nurses were higher for dosimeters located above the aprons than those for dosimeters located under the aprons. Above the apron, the average effective doses accumulated during the study period were 0.44 ± 0.06, 0.34 ± 0.05, 0.29 ± 0.03 and 0.29 ± 0.04 mSv, respectively; whereas, under the apron, they were 0.20 ± 0.02, 0.18 ± 0.02, 0.17 ± 0.02 and 0.18 ± 0.02, respectively. Also, the fluoroscopy time was correlated with the dose acquired, especially for senior cardiologists. It is concluded that doses to senior cardiologists are quite high, and that many variables can affect staff exposure such as distance, direction, procedure and skills.


Assuntos
Anestesiologistas , Cardiologistas , Enfermeiras e Enfermeiros , Exposição Ocupacional/análise , Doses de Radiação , Fluoroscopia , Hospitais Universitários , Humanos , Papel Profissional , Dosimetria Termoluminescente , Raios X
6.
Isotopes Environ Health Stud ; 53(4): 427-439, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28286974

RESUMO

Twenty soil and 25 sediment samples were collected from the banks and bottom of the River Nile in the surroundings of biggest cities located close to it. Natural radioactivity concentrations of 226Ra, 232Th and 40K have been evaluated for all samples by means of γ spectrometric analysis. The radioactivity levels of soil and sediment samples fall within the internationally recommended values. Nevertheless, high natural background radiation zones are detected in the Kafr El-Zayat region due to the presence of a fertilizer factory, and in the Rosetta region due to the presence of black sand deposits. The absorbed dose rate, the γ index and excess life time cancer risk are calculated. High values for some of the radiation health parameters are detected in the Kafr El-Zayat and Rosetta regions representing a serious problem to public health because the soil and sediment are used as constructing material for buildings. Furthermore, the isotope analysis of uranium for representative collected sediment samples via α spectrometry showed average specific activities of 18.7 ± 3.6, 0.087 ± 0.0038 and 18.6 ± 3.8 Bq kg-1 for 234U, 235U and 238U, respectively. In general, these values confirm the balance in the isotopic abundance of U isotopes.


Assuntos
Radiação de Fundo , Monitoramento de Radiação/métodos , Rios/química , Poluentes Radioativos do Solo/análise , Poluentes Radioativos da Água/análise , Egito , Sedimentos Geológicos/química , Radioisótopos de Potássio/efeitos adversos , Radioisótopos de Potássio/análise , Saúde Pública , Rádio (Elemento)/efeitos adversos , Rádio (Elemento)/análise , Solo/química , Poluentes Radioativos do Solo/efeitos adversos , Espectrometria gama , Tório/efeitos adversos , Tório/análise , Urânio/efeitos adversos , Urânio/análise , Poluentes Radioativos da Água/efeitos adversos
7.
Int J Dent Hyg ; 14(4): 261-266, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26250477

RESUMO

OBJECTIVES: The aim of this randomized, controlled trial was to evaluate the effects of 685-nm gallium aluminium arsenide (GaAlAs) diode laser therapy (1.6 J cm-2 ) as an adjunct to scaling and root planing in the treatment of chronic periodontitis. METHODS: Thirty-two patients aged 35-60 years old who had chronic periodontitis met the eligibility criteria. They were randomly assigned to two equal groups: scaling and root planing were performed in the SRP group, while scaling, root planing and laser irradiation of periodontal pockets were performed in the SRP + DL group. Subgingival plaque samples were subjected to polymerase chain reaction (PCR) to detect P. gingivalis-colonized sites, and common clinical indices were evaluated before and 2 months after treatment. Clinical examination included gingival index (GI), plaque index (PI), probing depth (PD), clinical attachment level (CAL) and gingival bleeding index (GBI), all of which were recorded. RESULTS: Data from 30 patients [19 women and 11 men; mean age, 48.4 (5.4) years old] were analysed. There were statistically significant improvements in GI, PD, CAL and GBI for the SRP + DL group compared to SRP group but no significant difference in PI between the groups. Additionally, the percentage of P. gingivalis-positive sites in the SRP + DL group decreased from 80% (12/15) to 20% (3/15) after laser irradiation (P < 0.05). No significant changes were noted in the SRP group. CONCLUSION: GaAlAs diode laser irradiation of diseased periodontal pockets at 685 nm and 1.6 J cm-2 seemed to be an effective adjuvant to mechanical instrumentation to treat chronic periodontitis.


Assuntos
Periodontite Crônica/radioterapia , Lasers Semicondutores/uso terapêutico , Terapia com Luz de Baixa Intensidade/métodos , Porphyromonas gingivalis/efeitos da radiação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
Appl Radiat Isot ; 69(10): 1506-11, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21723139

RESUMO

The aim of the present study is to assess the current level of atmospheric heavy metal pollution of aerosols in different cities of North Egypt using the neutron activation analysis and optical emission inductively coupled plasma techniques. The results revealed that the highest concentrations of particulate matter PM10 and total suspended particulate matter were close to industrial areas. From the results of the enrichment factor calculations, the most significant elements of anthropogenic origin are Ba, Sb, Ce and Zn.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Poluição Ambiental/análise , Cidades , Egito , Metais Pesados/análise , Análise de Ativação de Nêutrons , Material Particulado
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