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1.
Rev Neurol (Paris) ; 178(1-2): 21-33, 2022.
Article in English | MEDLINE | ID: mdl-34392974

ABSTRACT

Delayed awakening is defined as a persistent disorder of arousal or consciousness 48 to 72h after sedation interruption in critically ill patients. Delayed awakening is either a component of coma or delirium. It results in longer hospital stays and increased mortality. It is therefore a diagnostic, therapeutic and prognostic emergency. In severe brain injured patients, delayed awakening may be related to the primary neurological injury or to secondary systemic insults related to organ failure associated with intensive care. In the present review, we propose diagnostic, therapeutic and prognostic algorithms for managing delayed awaking in neuro-ICU brain injured patients.


Subject(s)
Critical Illness , Intensive Care Units , Coma/diagnosis , Coma/etiology , Coma/therapy , Critical Care , Humans , Length of Stay
3.
Neuromuscul Disord ; 31(8): 726-735, 2021 08.
Article in English | MEDLINE | ID: mdl-34304969

ABSTRACT

The tolerance of exercise and its effects on quality of life in myasthenia gravis are not currently backed up by strong evidence. The aim of this study was to determine whether exercise as an adjunct therapy is well tolerated and can improve health-related quality of life (HRQoL) in stabilized, generalized autoimmune myasthenia gravis (gMG). We conducted a parallel-group, multi-center prospective RCT using computer-generated block randomization. Adults with stabilized, gMG, and no contra-indication to exercise, were eligible. Participants received usual care alone or usual care and exercise. The exercise intervention consisted of 3-weekly 40 min sessions of an unsupervised, moderate-intensity home rowing program over 3 months. The primary endpoint was the change in HRQoL from randomization to post-intervention. Assessor-blinded secondary endpoints were exercise tolerance and effects on clinical, psychological and immunological status. Of 138 patients screened between October 2014 and July 2017, 45 were randomly assigned to exercise (n = 23) or usual care (n = 20). Although exercise was well tolerated, the intention-to-treat analysis revealed no evidence of improved HRQoL compared to usual care (MGQOL-15-F; mean adjusted between-groups difference of -0.8 points, 95%CI -5.4 to 3.7). Two patients hospitalized for MG exacerbation were from the usual care group.


Subject(s)
Exercise Therapy/methods , Myasthenia Gravis/therapy , Adult , Aged , Exercise , Exercise Tolerance , Female , Humans , Male , Middle Aged , Prospective Studies , Quality of Life
4.
Nanotechnology ; 31(18): 185403, 2020 May 01.
Article in English | MEDLINE | ID: mdl-31952052

ABSTRACT

This work aims to develop and characterize a new design of free-standing interconnected carbon nanofiber electrodes for supercapacitor application. The fibers are obtained via carbonization of three components of electrospun nanofiber mats based on a polyacrylonitrile polymer (as a carbon backbone precursor), polyvinylalcohol (as a sacrificial copolymer), and 0-1.0 wt% multi-walled carbon nanotubes. Carbonizing these ternary composites results in fibers with about twice as large in surface area and one order of magnitude higher in electrical conductivity than those obtained by the carbonization of neat polyacrylonitrile and/or binary polyacrylonitrile-0-1.0 wt% carbon nanotube mats. The carbonized polyacrylonitrile-polyvinylalcohol-0.3 wt% carbon nanotube mat reveals the highest surface area and electrical conductivity and best capacitive performance. It exhibits energy and power densities of 27.8 Wh kg-1 and 110.59 kW kg-1, respectively, and cyclic stability of 95% after 2000 charge-discharge cycles at a charging current of 1.0 Ag-1. The nanotubes' alignment along the fiber's axis, the formation of fiber-fiber interconnected morphology with more mesopore pollution, and changes in the graphitization degree and defect features of fiber crystallites are the reasons for the observed increase in the electrical conductivity, surface area, and capacitive performance of the carbon fibers. Therefore, the new design represents a potential free-standing carbon nanofiber electrode for future electrochemical double layer capacitor (EDLC) device fabrication.

5.
Rev Neurol (Paris) ; 175(9): 564-567, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31053354

ABSTRACT

Although relatively common in children, severe acute lactic acidosis is rare in adults with mitochondrial myopathies. We report here three cases, aged 27, 32 and 32 years, who developed life-threatening metabolic crisis with severe lactic acidosis, requiring hospitalisation in intensive care unit. Plasma lactates were elevated 10 to 15 fold normal values, necessitating extra-renal dialysis. By contrast CK levels were moderately increased (3 to 5N). No triggering factor was identified, but retrospectively all patients reported long-lasting mild muscle fatigability and weakness before their acute metabolic crisis. All of them recovered after prolonged intensive care but resting lactate levels remained elevated. Muscle biopsy showed ragged-red and COX-negative fibers in two patients and mild lipidosis in the third one. Heteroplasmic pathogenic point mutations were detected in MT-TL1 (m.3280G>A;m.3258C>T) and MT-TK (m.8363A>G). Life-threatening lactic acidosis may thus be a major inaugural clinical manifestation in adults with mitochondrial myopathies. Prolonged intensive care may lead to a dramatic and sustained improvement and is mandatory in such cases.


Subject(s)
Acidosis, Lactic/etiology , Acidosis, Lactic/therapy , Critical Care , Mitochondrial Diseases/complications , Mitochondrial Diseases/therapy , Acidosis, Lactic/diagnosis , Adult , Critical Illness/therapy , Emergencies , Female , Humans , Male , Mitochondrial Diseases/diagnosis , Mitochondrial Diseases/pathology , Retrospective Studies
6.
Br J Anaesth ; 121(6): 1290-1297, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30442256

ABSTRACT

BACKGROUND: Mismatch negativity (MMN) is the neurophysiological correlate of cognitive integration of novel stimuli. Although MMN is a well-established predictor of awakening in non-sedated comatose patients, its prognostic value in deeply sedated critically ill patients remains unknown. The aim of this prospective, observational pilot study was to investigate the prognostic value of MMN for subsequent awakening in deeply sedated critically ill patients. METHODS: MMN was recorded in 43 deeply sedated critically ill patients on Day 3 of ICU admission using a classical 'odd-ball' paradigm that delivers rare deviant sounds in a train of frequent standard sounds. Individual visual analyses and a group level analysis of recordings were performed. MMN amplitudes were then analysed according to the neurological status (awake vs not awake) at Day 28. RESULTS: Median (inter-quartile range) Richmond Assessment Sedation Scale (RASS) at the time of recording was -5 (range, from -5 to -4.5). Visual detection of MMN revealed a poor inter-rater agreement [kappa=0.17, 95% confidence interval (0.07-0.26)]. On Day 28, 30 (70%) patients had regained consciousness while 13 (30%) had not. Quantitative group level analysis revealed a significantly greater MMN amplitude for patients who awakened compared with those who had not [mean (standard deviation) = -0.65 (1.4) vs 0.08 (0.17) µV, respectively; P=0.003). CONCLUSIONS: MMN can be observed in deeply sedated critically ill patients and could help predict subsequent awakening. However, visual analysis alone is unreliable and should be systematically completed with individual level statistics.


Subject(s)
Critical Illness , Deep Sedation , Wakefulness , Adult , Aged , Aged, 80 and over , Cognition , Consciousness , Evoked Potentials , Female , Humans , Male , Middle Aged , Pilot Projects , Prospective Studies
7.
J Neuroimmunol ; 292: 108-15, 2016 Mar 15.
Article in English | MEDLINE | ID: mdl-26943968

ABSTRACT

Myasthenia gravis (MG) is an autoimmune disease caused by antibodies targeting the neuromuscular junction of skeletal muscles. Triple-seronegative MG (tSN-MG, without detectable AChR, MuSK and LRP4 antibodies), which accounts for ~10% of MG patients, presents a serious gap in MG diagnosis and complicates differential diagnosis of similar disorders. Several AChR antibody positive patients (AChR-MG) also have antibodies against titin, usually detected by ELISA. We have developed a very sensitive radioimmunoprecipitation assay (RIPA) for titin antibodies, by which many previously negative samples were found positive, including several from tSN-MG patients. The validity of the RIPA results was confirmed by western blots. Using this RIPA we screened 667 MG sera from 13 countries; as expected, AChR-MG patients had the highest frequency of titin antibodies (40.9%), while MuSK-MG and LRP4-MG patients were positive in 14.6% and 16.4% respectively. Most importantly, 13.4% (50/372) of the tSN-MG patients were also titin antibody positive. None of the 121 healthy controls or the 90 myopathy patients, and only 3.6% (7/193) of other neurological disease patients were positive. We thus propose that the present titin antibody RIPA is a useful tool for serological MG diagnosis of tSN patients.


Subject(s)
Autoantibodies/blood , Connectin/immunology , Myasthenia Gravis/blood , Myasthenia Gravis/diagnosis , Enzyme-Linked Immunosorbent Assay , Female , Humans , International Cooperation , LDL-Receptor Related Proteins/immunology , Male , Myasthenia Gravis/epidemiology , Radioimmunoprecipitation Assay , Receptor Protein-Tyrosine Kinases/immunology , Receptors, Cholinergic/immunology
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 159: 238-48, 2016 Apr 15.
Article in English | MEDLINE | ID: mdl-26867205

ABSTRACT

Polymeric sheets of poly (methylmethaclyerate) (PMMA) containing charge transfer (CT) complex of rhodamine B/chloranilic acid (Rho B/CHA) were synthesized in methanol solvent at room temperature. The systematic analysis done on the Rho B and its CT complex in the form of powder or polymeric sheets confirmed their structure and thermal stability. The IR spectra interpreted the charge transfer mode of interaction between the CHA central positions and the terminal carboxylic group. The polymer sheets were irradiated with 70 kGy of γ radiation using (60)Co source to study the enhanced changes in the structure and optical parameters. The microstructure changes of the PMMA sheets caused by γ-ray irradiation were analyzed using positron annihilation lifetime (PAL) and positron annihilation Doppler broadening (PADB) techniques. The positron life time components (τ(i)) and their corresponding intensities (I(i)) as well as PADB line-shape parameters (S and W) were found to be highly sensitive to the enhanced disorder occurred in the organic chains of the polymeric sheets due to γ-irradiation.

9.
Nat Commun ; 6: 10145, 2015 Dec 15.
Article in English | MEDLINE | ID: mdl-26666572

ABSTRACT

Sepsis, or systemic inflammatory response syndrome, is the major cause of critical illness resulting in admission to intensive care units. Sepsis is caused by severe infection and is associated with mortality in 60% of cases. Morbidity due to sepsis is complicated by neuromyopathy, and patients face long-term disability due to muscle weakness, energetic dysfunction, proteolysis and muscle wasting. These processes are triggered by pro-inflammatory cytokines and metabolic imbalances and are aggravated by malnutrition and drugs. Skeletal muscle regeneration depends on stem (satellite) cells. Herein we show that mitochondrial and metabolic alterations underlie the sepsis-induced long-term impairment of satellite cells and lead to inefficient muscle regeneration. Engrafting mesenchymal stem cells improves the septic status by decreasing cytokine levels, restoring mitochondrial and metabolic function in satellite cells, and improving muscle strength. These findings indicate that sepsis affects quiescent muscle stem cells and that mesenchymal stem cells might act as a preventive therapeutic approach for sepsis-related morbidity.


Subject(s)
Mesenchymal Stem Cell Transplantation , Mitochondria, Muscle/metabolism , Satellite Cells, Skeletal Muscle/pathology , Sepsis/complications , Stem Cells/pathology , Animals , Cells, Cultured , Cytokines/genetics , Cytokines/metabolism , Gene Expression Regulation , Male , Mice , Mice, Transgenic , Peritonitis/complications , Reactive Oxygen Species/metabolism , Regeneration , Sepsis/metabolism , Stem Cells/metabolism
10.
Environ Monit Assess ; 187(9): 583, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26297416

ABSTRACT

Non-nuclear industries use raw materials containing significant levels of naturally occurring radioactive material (NORM). The processing of these materials may expose workers engaged in or even people living near such sites to technologically enhanced naturally occurring radioactive material (TENORM) above the natural background. Inductively coupled plasma and gamma ray spectrometry have been used to determine major and trace elements and radionuclide concentrations in various samples, respectively, in order to investigate the environmental impact of coal mining and cement plant in North Sinai, Egypt. Generally, very little attention was directed to the large volumes of waste generated by either type of industrial activities. Different samples were analyzed including various raw materials, coal, charcoal, Portland and white cement, sludge, and wastes. Coal mine and cement plant workers dealing with waste and kaolin, respectively, are subjected to a relatively high annual effective dose. One of the important finding is the enhancement of all measured elements and radionuclides in the sludge found in coal mine. It may pose an environmental threat because of its large volume and its use as combustion material. The mine environment may have constituted Al, Fe, Cr, and V pollution source for the local area. Higher concentration of Al, Fe, Mn, B, Co, Cr, Mn, Ni, Sr, V, and TENORM were found in Portland cement and Zn in white cement. Coal has higher concentrations of Al, Fe, B, Co, Cr, and V as well as (226)Ra and (232)Th. The compiled results from the present study and different worldwide investigations demonstrate the obvious unrealistic ranges normally used for (226)Ra and (232)Th activity concentrations in coal and provided ranges for coal, Portland and white cement, gypsum, and limestone.


Subject(s)
Coal Mining , Radioactive Pollutants/analysis , Radioisotopes/analysis , Boron/analysis , Coal/analysis , Egypt , Environmental Monitoring , Industrial Waste/analysis , Metals/analysis , Sewage/analysis
11.
Article in English | MEDLINE | ID: mdl-25965516

ABSTRACT

New vanadium(IV) and chromium(III) complexes of metformin (MFN) were synthesized upon the chemical interaction between vanadyl(II) sulfate monohydrate or chromium(III) chloride hexahydrate with metformin diabetic drug in the media of a pure grade of methanol solvent. The [(VO)2(MFN)2(SO4)2]2H2O and [Cr(MFN)3]·Cl3·6H2O complexes were discussed using microanalytical measurements, molar conductance, spectroscopic (infrared, ESR, XRD, and UV-vis), effective magnetic moment, scanning electron microscopy (SEM), and thermal analyses (TG/DTG). The elemental analysis shows that VO(II) and Cr(III) complexes were associated with 1:1 and 1:3M ratios, respectively. The infrared spectroscopic results data received from the comparison between free MFN free ligand and their vanadyl(II) and chromium(III) complexes were proven that metformin reacted with respected metal ions as a bidentate ligand through its two imino groups. The kinetic thermodynamic parameters were estimated from the DTG curves. The microstructure changes of the VO(II) and Cr(III) complexes have been probed using positron annihilation lifetime (PAL) and positron annihilation Doppler broadening (PADB) techniques. The PAL and PADB line-shape parameters were found to be dependent on the structure, electronic configuration and molecular weight of metal complexes. Antimicrobial activity of the metformin free ligand and its vanadyl(II) and chromium(III) complexes were evaluated against the gram negative and gram positive bacteria strains and different fungal strains. Moderate antimicrobial activity recorded by disk diffusion inhibition growth zone method in vanadyl(II) and chromium(III) complexes compared to metformin free ligand.


Subject(s)
Anti-Infective Agents/chemistry , Chromium/chemistry , Coordination Complexes/chemistry , Metformin/analogs & derivatives , Vanadium/chemistry , Anti-Infective Agents/chemical synthesis , Anti-Infective Agents/pharmacology , Bacterial Infections/drug therapy , Chromium/pharmacology , Coordination Complexes/chemical synthesis , Coordination Complexes/pharmacology , Fungi/drug effects , Humans , Metformin/chemical synthesis , Metformin/pharmacology , Microbial Sensitivity Tests , Mycoses/drug therapy , Vanadium/pharmacology
12.
J Neuroimmunol ; 284: 10-7, 2015 Jul 15.
Article in English | MEDLINE | ID: mdl-26025053

ABSTRACT

Seronegative myasthenia gravis (MG) presents a serious gap in MG diagnosis and understanding. We applied a cell based assay (CBA) for the detection of muscle specific kinase (MuSK) antibodies undetectable by radioimmunoassay. We tested 633 triple-seronegative MG patients' sera from 13 countries, detecting 13% as positive. MuSK antibodies were found, at significantly lower frequencies, in 1.9% of healthy controls and 5.1% of other neuroimmune disease patients, including multiple sclerosis and neuromyelitis optica. The clinical data of the newly diagnosed MuSK-MG patients are presented. 27% of ocular seronegative patients were MuSK antibody positive. Moreover, 23% had thymic hyperplasia suggesting that thymic abnormalities are more common than believed.


Subject(s)
Autoantibodies/blood , Myasthenia Gravis/blood , Myasthenia Gravis/diagnosis , Receptor Protein-Tyrosine Kinases/immunology , Adult , Aged , Female , Flow Cytometry , Humans , International Cooperation , LDL-Receptor Related Proteins/immunology , Male , Middle Aged , Myasthenia Gravis/pathology , Neuromyelitis Optica/diagnosis , Radioimmunoassay , Receptors, Cholinergic/immunology , Thymus Gland/pathology , Thymus Hyperplasia/diagnosis
13.
J Environ Radioact ; 134: 35-42, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24657852

ABSTRACT

In the present study, measurements of naturally occurring radioactive materials and (137)Cs activity in sediment were conducted for locations covering the entire Burullus Lake in order to gather information about radionuclides mobility and distribution. Low-background γ-spectrometry was employed to determine the activity concentrations of water and sediment samples. The activity concentrations of (226)Ra and (232)Th are close to uniform distribution in the lake environment. Among the different physical and chemical characteristics measured for water and sediment, only salinity and total organic matter content have the potential to affect the mobility of (137)Cs and (40)K. The results suggest that these two radionuclides are attached to different mobile particulates. Increasing salinity tends to strengthen the adsorption of (137)Cs and solubilization of (40)K in sediment. On the other hand, sediment with high organic matter content traps (137)Cs and (40)K associated particulates to bottom sediment.


Subject(s)
Radioisotopes/analysis , Cesium Radioisotopes/analysis , Lakes/chemistry , Potassium Radioisotopes/analysis , Radiation Monitoring , Radium/analysis , Soil Pollutants, Radioactive/analysis , Spectrometry, Gamma , Thorium/analysis , Uranium/analysis
14.
Epidemiol Infect ; 142(8): 1609-13, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24107359

ABSTRACT

The role of Campylobacter jejuni as the triggering agent of Guillain-Barré syndrome (GBS) has not been reassessed since the end of the 1990s in France. We report that the number of C. jejuni-related GBS cases increased continuously between 1996 and 2007 in the Paris region (mean annual increment: 7%, P = 0·007).


Subject(s)
Campylobacter Infections/complications , Campylobacter jejuni/immunology , Guillain-Barre Syndrome/epidemiology , Adult , Aged , Female , France , Humans , Incidence , Male , Middle Aged , Paris/epidemiology
15.
Article in English | MEDLINE | ID: mdl-24291622

ABSTRACT

In this work, structural, thermal, morphological, pharmacological screening and positron annihilation lifetime measurements were performed on the interactions between a N-(1-Naphthyl)ethylenediamine dihydrochloride (NEDA·2HCl) donor and three types of acceptors to characterize these CT complexes. The three types of acceptors include π-acceptors (quinol and picric acid), σ-acceptors (iodine) and vacant orbital acceptors (tin(IV) tetrachloride and zinc chloride). The positron annihilation lifetime parameters were found to be dependent on the structure, electronic configuration, the power of acceptors and molecular weight of the CT complexes. The positron annihilation lifetime spectroscopy can be used as a probe for the formation of charge-transfer (CT) complexes.


Subject(s)
Electrons , Ethylenediamines/chemistry , Spectrum Analysis/methods , Anti-Bacterial Agents/pharmacology , Bacteria/drug effects , Ethylenediamines/pharmacology , Kinetics , Lasers , Methanol/chemistry , Microbial Sensitivity Tests , Microscopy, Electron, Scanning , Proton Magnetic Resonance Spectroscopy , Solvents/chemistry , Spectrometry, X-Ray Emission , Spectrophotometry, Infrared , Spectrum Analysis, Raman , Thermogravimetry , X-Ray Diffraction
16.
Article in English | MEDLINE | ID: mdl-22595252

ABSTRACT

Molecular charge-transfer complexes of the tetramethylethylenediamine (TMEDA) with picric acid (Pi-OH), benzene-1,4-diol (QL), tin(IV) tetrachloride (SnCl(4)), iodine, bromine, and zinc chloride (ZnCl(2)) have been synthesized and investigated by elemental and thermal analysis, electronic, infrared, Raman and proton-NMR, energy-dispersive X-ray spectroscopy, X-ray powder diffraction and positron annihilation lifetime spectroscopy, and scanning electron microscopy. In this work, three types of acceptors π-acceptors (Pi-OH and QL), σ-acceptors (iodine and bromine), and vacant orbital acceptors (SnCl(4) and ZnCl(2)) were covered. The results of elemental analysis indicated that the CT complexes were formed with ratios 1:1 and 1:2 for QL, SnCl(4), and ZnCl(2) acceptors and iodine, Pi-OH, and Br(2) acceptors, respectively. The type of chelating between the TMEDA donor and the mentioned acceptors depends upon the behavior of both items. The positron annihilation lifetime parameters were found to be dependent on the structure, electronic configuration, and the power of acceptors. The correlation between these parameters and the molecular weight and biological activities of studied complexes was also observed. Regarding the electrical properties, the AC conductivity and the dielectric coefficients were measured as a function of frequency at room temperature. The TMEDA charge-transfer complexes were screened against antibacterial (Escherichia coli, Staphylococcus aureus, Bacillus subtilis, and Pseudomonas aeruginosa) and antifungal (Aspergillus flavus and Candida albicans) activities.


Subject(s)
Electric Conductivity , Electrons , Organometallic Compounds/chemistry , Organometallic Compounds/chemical synthesis , Spectrum Analysis/methods , Bacteria/drug effects , Bromine/chemistry , Bromine/pharmacology , Chlorides/chemistry , Fungi/drug effects , Iodine/chemistry , Iodine/pharmacology , Magnetic Resonance Spectroscopy , Microbial Sensitivity Tests , Organometallic Compounds/pharmacology , Photometry , Picrates/chemistry , Picrates/pharmacology , Spectrophotometry, Infrared , Spectrum Analysis, Raman , Temperature , Thermogravimetry , Titrimetry , Zinc Compounds/chemistry
17.
Radiat Prot Dosimetry ; 145(4): 411-20, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21148168

ABSTRACT

This work describes the concentrations of radioisotopes in soil, sediment, wild plants and groundwater in southwestern Sinai. The study area extends from Suez to Abu Rudies along the eastern part of the Suez Gulf. It included two hot springs: Ayun Musa and Hammam Faraoun. No dependence of ¹³7Cs concentrations on any of the measured sand characteristics was found, including calcium carbonate. The enrichment of ²²6Ra in Hammam Faraoun hot spring was the most prominent feature. The ²²6Ra concentration in hot springs of Ayun Musa and Hammam Faraoun were 68 and 2377 Bq kg⁻¹ for sediments, 3.5 and 54.0 Bq kg⁻¹ for wild plants and 205 and 1945 mBq l⁻¹ for the groundwater, respectively. In addition, ²²6Ra activity concentration in local sand in the area of Hammam Faraoun was ∼14 times that of Ayun Musa. On the other hand, the ²³²Th concentrations were comparable in the two hot springs, while ¹³7Cs concentrations were relatively higher in Ayun Musa. The characteristics and radioelements studies support possible suggestions that the waters in the two hot springs have different contributions of sea and groundwaters crossing different geological layers where the water-rock interaction takes place.


Subject(s)
Environmental Monitoring , Hot Springs/chemistry , Plants/chemistry , Radioactive Pollutants/analysis , Water/chemistry , Cesium/analysis , Egypt , Environmental Exposure , Gamma Rays , Geologic Sediments/chemistry , Humans , Radiation Dosage , Radioisotopes/analysis , Radium/analysis , Seawater/chemistry , Silicon Dioxide/chemistry , Thorium/analysis , Uranium/analysis
18.
Radiat Prot Dosimetry ; 135(4): 261-7, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19561154

ABSTRACT

This study compares the external dose due to the gamma-ray emitting radionuclides in various areas in North Sinai, Egypt. The whole area was divided into 10 regions. The average absorbed dose rates were evaluated for each region. It was found that Zaranik-protected area and Al-Massaid have the highest values of 72.7 and 57.2 nGy h(-1), respectively. The corresponding values of the remaining regions were <23 nGy h(-1). The mean annual effective dose equivalents for the four largest cities Rafah, El-Sheikh Zuwaied, Al-Arish and Bir El-Abd were 20.8, 18.8, 57.4 and 14.0 microSv, respectively. The results are compared with those from different areas in Egypt and in various countries.


Subject(s)
Body Burden , Environmental Exposure/analysis , Geologic Sediments/analysis , Geologic Sediments/chemistry , Radiation Monitoring , Radioisotopes/analysis , Egypt , Gamma Rays
19.
Appl Radiat Isot ; 67(9): 1721-8, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19433365

ABSTRACT

Computational methods were used to reduce the dimensionality and to find clusters of multivariate data. The variables were the natural radioactivity contents and the texture characteristics of sand samples. The application of discriminate analysis revealed that samples with high negative values of the former score have the highest contamination with black sand. Principal component analysis (PCA) revealed that radioactivity concentrations alone are sufficient for the classification. Rough set analysis (RSA) showed that the concentration of (238)U, (226)Ra or (232)Th, combined with the concentration of (40)K, can specify the clusters and characteristics of the sand. Both PCA and RSA show that (238)U, (226)Ra and (232)Th behave similarly. RSA revealed that one or two of them can be omitted without degrading predictions.

20.
Appl Radiat Isot ; 67(7-8): 1259-68, 2009.
Article in English | MEDLINE | ID: mdl-19282198

ABSTRACT

The environmental pollution caused by the wastewater from a phosphate fertilizer plant in Egypt was investigated. The concentrations of radionuclides and fluoride in phosphate fertilizer (raw materials, end products and by-products) and other types of fertilizer samples were measured. The concentrations of these elements were also measured in environmental samples (water, sediment and plant) collected from the proximity of outlet of wastewater discharge pipes of the phosphate fertilizer company. The fluoride concentration was ranged from 0.03 to 0.25mg/g, 0.002 to 0.006mg/g, 0.42 to 1.88mg/g and 0.44 to 7.3mg/l for phosphate fertilizer, other types of fertilizer, sediment and water samples, respectively. The activity concentrations of (226)Ra were ranged from 244 to 1312Bq/kg, 0.6 to 12.1Bq/kg, 15.4 to 33.8Bq/kg, 0.06 to 1.3Bq/l and 8.9 to 17.3Bq/kg for phosphate fertilizer, other types of fertilizer, sediment, water and plant samples, respectively. The (232)Th activity concentrations were ranged from 0.7 to 24Bq/kg, 0.7 to 14.5Bq/kg, 10.4 to 19.3Bq/kg, 0.02 to 0.16Bq/l and 2.0 to 29.8Bq/kg for these samples, respectively. Also, the (40)K activity concentrations were ranged from 2.1 to 1.4Bq/kg, 2.1 to 5313Bq/kg, 128 to 281Bq/kg, 0.14 to 0.6Bq/l and 686 to 977Bq/kg for these samples, respectively. Low content of (137)Cs was determined in only two phosphate fertilizer samples (F2 and F3; mean 1.3Bq/kg) and in most of sediment samples (with range 1.0-2.4Bq/kg). The radium equivalent, as a radiation hazard index, was ranged from 284 to 1316, 9.6 to 432 and 47 to 70Bq/kg for phosphate fertilizer, other types of fertilizer and sediment samples, respectively. The results indicated that the wastewater polluted with fluoride produced from the phosphate fertilizer company may be affecting the environment. The radioactivity content measurements indicated that the environment may be slightly affected with low concentrations of (226)Ra and (232)Th isotopes due to the discharged wastewater from the phosphate fertilizer industry. On the other hand, the results of comparison studies for radioactivity concentrations are also presented and discussed.


Subject(s)
Fertilizers , Fluorides/analysis , Industrial Waste/analysis , Radioactive Pollutants/analysis , Chemical Industry , Egypt , Phosphates , Plants/chemistry , Soil Pollutants, Radioactive/analysis , Water Pollutants, Radioactive/analysis
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