Radiological impact of natural radioactivity in Egyptian phosphate rocks, phosphogypsum and phosphate fertilizers.

In this study, the activity concentrations of the natural radionuclides in phosphate rocks and its products were measured using a high- purity germanium detector (HPGe). The obtained activity results show remarkable wide variation in the radioactive contents for the different phosphate samples. The average activity concentration of 235U, 238U, 226Ra, 232Th and 40K was found as (45, 1031, 786, 85 and 765Bq/kg) for phosphate rocks, (28, 1234, 457, 123 and 819Bq/kg) for phosphate fertilizers, (47, 663, 550, 79 and 870Bq/kg) for phosphogypsum and (25, 543, 409, 54 and 897Bq/kg) for single super phosphate respectively. Based on the measured activities, the radiological parameters (activity concentration index, absorbed gamma dose rate in outdoor and indoor and the corresponding annual effective dose rates and total excess lifetime cancer risk) were estimated to assess the radiological hazards. The total excess lifetime cancer risk (ELCR) has been calculated and found to be high in all samples, which related to high radioactivity, representing radiological risk for the health of the population.

Nano-odontology: nanostructured assemblies for endodontic regeneration.

The vitality of the pulp is so fundamental to the functional life of the tooth that new strategies are required to avoid the removal of the whole pulp following irreversible pulpitis and to regenerate the lost endodontic tissues. Nano-odontology would provide suitable solutions for pulp tissue conservative and regenerative approaches. In our group, we have shown that when covalently coupled to Poly-Glutamic Acid (PGA) the incorporation of an anti-inflammatory hormone (melanocortin, a-MSH) into the multilayered films Poly-L-Lysine (PLL)/PGA increases the anti-inflammatory reaction of pulp fibroblasts and macrophages stimulated by LPS (Lipo-Polysaccharides). Recently, usual linear PLL polymers have been chemically grafted for making new Dendrigraft polymers (DGLG4) whose higher branching ratios can give useful properties. The objective is to use nanostructured assemblies containing DGLG4 and PGA-alpha-MSH to design a new nanomaterial. These nanostructured assemblies (DGLG4-PGA-alpha-MSH)n constitute a thick reservoir of the anti-inflammatory peptide and promote adhesion and proliferation of pulp fibroblast on the biomaterial surface. These nanostructured films could be adapted for an endodontic regeneration application to target pulp connective tissue regeneration. Firstly, the crucial reduction of inflammation could be helpful by using PGA-alpha-MSH and secondly the initiation of the regeneration of the connective tissue will be promoted by the whole nanostructured film of which allows pulp cells colonisation.

Assessment of radioactivity and radon exhalation rate in Egyptian cement.

The cement industry is considered as one of the basic industries that plays an important role in the national economy of developing countries. Activity concentration of 238U, 232Th, and 40K in local cement types from different Egyptian factories has been measured using a shielded HPGe detector. The average values obtained for 238U, 232Th, and 40K activity concentrations in different types of cement are lower than the corresponding global values reported in UNSCEAR publications. On the basis of the hazard index and the radium equivalent concentration, it can be shown that the natural radioactivity of cement samples is not greater than the values permitted in the established standards in other countries. A solid-state nuclear track detector SSNTD (Cr-39) was used to measure the radon concentration as well as exhalation rate for these samples. The effective radium content and the exhalation rate are found to vary from 12.75 to 38.52 Bq kg(-1) and 61.19 to 181.39 Bq m(-2) d(-1), respectively.

Elemental analysis of Egyptian phosphate fertilizer components.

The accumulation of certain elements in vitally important media such as water, soil, and food is undesirable from the medical point of view. It is clear that the fertilizers vary widely in their heavy metals and uranium content. A shielded high purity germanium HPGe detector has been used to measure the natural concentration of 238U, 232Th, and 40K activities in the phosphate fertilizer and its components collected from Abu-Zaabal fertilizers and chemical industries in Egypt. The concentration ranges were 134.97-681.11 Bq kg(-1), 125.23-239.26 Bq kg(-1), and 446.11-882.45 Bq kg(-1) for 238U, 232Th, and 40K, respectively. The absorbed dose rate and external hazard index were found to be from 177.14 to 445.90 nGy h(-1) and 1.03 to 2.71 nGy y(-1), respectively. The concentrations of 22 elements (Be, Na, Mg, Si, P, S, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, Zr, Mo, Cd, Ba) in the samples under investigation were determined by inductively coupled plasma optical-emission spectrometry (ICP-OES). The results for the input raw materials (rock phosphate, limestone and sulfur) and the output product as final fertilizer are presented and discussed.

Radioactivity in local and imported kaolin types used in Egypt.

Natural radioactive materials are present in all geological rocks in varying amounts, they are easily mobilized in the environment, and can reach hazardous radiological levels under certain conditions, requiring precautions to be taken. The present study deals with 50 geological samples of local (Tushki and Kalabsha in upper Egypt) and imported (southeast Asia and Turkey) kaolin types. The samples were analyzed by gamma-ray spectroscopy using a HPGe detector. The activity concentrations of 232Th and 238U series and 40K and the contents (in ppm) are given. The radium equivalent activity varied from 187.8 to 10185.19 Bq/kg. 137Cs was found in a range of 0.23-8.5 Bq/kg, for the local samples. The kaolin in Tushki area was suitable for industrial use.

Uso del intercambiador de tubos tipo Cook en la extubación de un paciente con intubación difícil / Using a Cook-type tube exchanger when extubating a patient with a difficult airway

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Radioactivity levels of salt for natural sediments in the northwestern desert and local markets in Egypt.

Thirteen samples of salt collected from different locations of old sediments in the western desert at El-Harra and Ain Giffara, Sitra lake and local markets in Egypt have been investigated. Natural radionuclide contents have been measured by gamma-ray spectrometry employing a shielded HPGe detector. The activities of 238U, 232Th and 40K have been determined in Bq/kg dry weight. The absorbed dose rate of gamma radiation was estimated to be 1.46-16.13 nGy/h. The thorium-to-uranium concentration ratios were also estimated for the samples.

Colocación de un tubo de doble luz mediante fibrobroncoscopio de 6 mm de diámetro e intercambiador de tubos Cook a un paciente con intubación traqueal difícil no prevista / Insertion of a double-lumen endobronchial tube with a 6 mm fiberoptic bronchoscope and a Cook airway exchange catheter in a patient with an unanticipated difficult airway

Varón de 74 años programado para neumonectomía izquierda, en el que no se preveía dificultad de intubación traqueal. Tras la inducción anestésica con midazolam, fentanilo, propofol y rocuronio, la laringoscopia objetivó Cormack-Lehane grado IV y tras dos intentos no se pudo intubar la traquea. Al no disponer de fibrobroncoscopio fino para intubación con tubo de doble luz, se utilizó un fibrobroncoscopio de 6 mm y se intubó al paciente con un tubo orotraqueal del nº 9 que se insertó en el bronquio principal izquierdo. La intubación se realizó con la ayuda de un adaptador universal para intubación fibroóptica con mascarilla facial y de una cánula de Williams, que permitieron ventilar manualmente al paciente con O2 al 100 por ciento mientras se realizó la fibroscopia. Dado que se precisaba ventilación selectiva durante la intervención, se insertó el intercambiador de tubos traqueales tipo Cook nº 11 en el bronquio principal izquierdo, se retiró el tubo traqueal, y se utilizó como guía el intercambiador, a través de la luz bronquial de un tubo de doble luz nº 39F izquierdo, que se introdujo sin dificultad, consiguiendo una intubación y ventilación selectivas satisfactorias. Ésta es una nueva indicación del intercambiador de tubos Cook que permite la intubación selectiva bronquial en caso de intubación traqueal difícil cuando no se dispone de fibrobroncoscopio fino (AU)

[Placement of a double-lumen tube using a 6 mm diameter fibro-bronchoscope and a Cook exchange catheter in a patient with unforeseen tracheal intubation difficulty]. / Colocación de un tubo de doble luz mediante fibrobroncoscopio de 6 mm de diámetro e intercambiador de tubos Cook a un paciente con intubación traqueal difícil no prevista.

The trachea of a 74-year-old man undergoing left pneumonectomy could not be intubated in two attempts after induction of anesthesia with midazolam, fentanyl, propofol and rocuronium. Difficult intubation had not been foreseen, but inspection through the laryngoscope revealed Cormack and Lehane grade IV conditions. Because a small-caliber fiberoptic bronchoscope was unavailable for intubation with a double-lumen endobronchial tube, we inserted a No. 9 orotracheal tube with a 6 mm bronchoscope as far as the left main bronchus. Intubation was aided by a universal adaptor for fiberoptics with a face mask and a Williams cannula. We were then able to ventilate the patient manually with 100% oxygen during bronchoscopy. As selective ventilation was required during surgery, a No. 11 Cook-type airway exchange catheter was inserted into the left main bronchus, the tracheal tube was removed, and was used to guide a No. 39F left double-lumen endobronchial tube through the bronchus. Insertion was uncomplicated and selective ventilation was satisfactory. The technique described is a new application for the Cook exchange catheter that allows selective bronchial in difficult cases when a small-caliber fiberoptic bronchoscope is unavailable.

Heavy metals and rare earth elements in phosphate fertilizer components using instrumental neutron activation analysis.

The technique of instrumental neutron activation analysis was applied as a sensitive nondestructive analytical tool for the determination of heavy metals and rare earth elements in phosphate fertilizer ingredients. The contents of heavy metals Fe, Zn, Co, Cr and Sc as well as rare earth elements La, Ce, Hf, Eu, Yb and Sm were determined in four samples representing the phosphate fertilizer components (e.g. rock phosphate, limestone and sulfur). These samples were collected from the Abu-Zabal phosphate factory in El-Qalubia governarate, Egypt. The aim of this study was to determine the elemental pattern in phosphate ingredients as well as in the produced phosphate fertilizer. Fair agreement was found between the results obtained for the standard reference material Soil-7 and the certified values reported by the International Atomic Energy Agency. The results for the input raw materials (rock phosphate, limestone and sulfur) and the output product as final fertilizer are presented and discussed.

Elemental investigation of some Egyptian vehicle motor alloys using neutron activation analysis.

Six samples of different Egyptian motor vehicle alloys have been investigated by neutron activation analysis to estimate the concentrations of their elemental constituents, which affect their quality. A single high resolution hyper-pure germanium HPGe gamma-ray detector and a multichannel analyzer are used to collect the gamma-ray spectra. A HPGe-HPGe coincidence spectrometer was also used to confirm the identity of certain peaks. Thirteen trace elements (Sc, Cr, Fe, Co, Zn, Sn, Sb, La, Sm, Eu, Hf, Pt and Au) were observed in the spectra and their concentrations were determined. A comparative study on the element concentrations for the six samples is given.

Natural radioactivity and radon exhalation rate of soil in southern Egypt.

The level of natural radioactivity in soil of 30 mining samples collected from six locations in southern Egypt was measured. Concentrations of radionuclides in samples were determined by gamma-ray spectrometer using HPGe detector with a specially designed shield. The obtained results of uranium and thorium series as well as potassium (K-40) are discussed. The present data were compared with data obtained from different areas in Egypt. Also, a solid state nuclear track detector SSNTD (Cr-39) was used to measure the radon concentration as well as exhalation rate for these samples. The radon concentrations were found to vary from 1.54 to 5.37 Bq/kg. The exhalation rates were found to vary from 338.81 to 1426.47 Bq/m2d. The values of the radon exhalation rate are found to correspond with the uranium concentration values measured by the germanium detector in the corresponding soil samples.

Mouse Alx3: an aristaless-like homeobox gene expressed during embryogenesis in ectomesenchyme and lateral plate mesoderm.

Mouse Alx3 is a homeobox gene that is related to the Drosophila aristaless gene and to a group of vertebrate genes including Prx1, Prx2, Cart1, and Alx4. The protein encoded contains a diverged variant of a conserved peptide sequence present near the carboxyl terminus of at least 15 different paired-class-homeodomain proteins. Alx3 is expressed in mouse embryos from 8 days of gestation onward in a characteristic pattern, predominantly in neural crest-derived mesenchyme and in lateral plate mesoderm. We detected prominent expression in frontonasal head mesenchyme and in the first and second pharyngeal arches and some of their derivatives. High expression was also seen in the tail and in many derivatives of the lateral plate mesoderm including the limbs, the body wall, and the genital tubercle. aristaless-related genes like Alx3, Cart1, and Prx2 are expressed in overlapping proximodistal patterns in the pharyngeal arches. Similar, but more lateral patterns have been described for the Distal-less-related (Dlx) genes. Intriguingly, expression and to some extent function of aristaless and Distal-less in Drosophila also have overlapping as well as complementary aspects. Alx3 was localized to chromosome 3, near the droopy-ear (de) mutation.