Publications by authors named "Haquin G"

A rapid method for determining low activity concentrations of Pb in drinking water was developed and tested. The method consists of a few stages for sample preparation that involve passing 12 L of water through a column with acrylic fibers implanted with MnO (used to adsorb Pb). The MnO fibers are oven-dried, compressed and measured by a broad-energy germanium detector used to quantify Pb via its characteristic 46.

View Article and Find Full Text PDF
Article Synopsis
  • - The study explored how changes in atmospheric temperature affect the flow of radon underground using a specialized climate-controlled lab, revealing that warming decreases radon concentration while cooling increases it, with significant rates of change observed.
  • - Radon flow was driven by temperature gradients, leading to a 30% change in concentration; cooling caused a rapid increase due to differences in air-soil temperatures, while overall molecular diffusion changed by around 7%.
  • - The research found a strong link between temperature cycles and radon concentration oscillations in low-frequency cycles (4-8 days), but this correlation weakened at higher frequencies, providing insights into underground radon behavior.
View Article and Find Full Text PDF

Nuclear simulation methods were applied to two systems that investigate radon transport within geological porous media: a) a laboratory system built to test, under controlled climate conditions, the effect of temperature on radon transport, and b) a field monitoring system comprising gamma and alpha detectors in an abandoned water well. The use of Monte Carlo simulations of NaI and BGO scintillation detectors in continuous underground radon measurements by gamma counting, to estimate the photon flux in the detector volume, is presented. The advantages of shielding side-view NaI detectors were demonstrated for a laboratory system containing ground phosphate rock, including avoiding high counting rates and reducing the effective source volume in radon transport studies.

View Article and Find Full Text PDF

The dependency of radon emanation on soil texture was investigated using the closed chamber method. Ground phosphate rock with a large specific surface area was analyzed, and the presence of inner pores, as well as a high degree of roughness and heterogeneity in the phosphate particles, was found. The average radon emanation of the dry phosphate was 0.

View Article and Find Full Text PDF

The radiation dose to the population of Israel due to exposure to natural sources of ionizing radiation was assessed. The main contributor to the dose is radon that accounts for 60% of the exposure to natural sources. The dose due to radon inhalation was assessed by combining the results of a radon survey in single-family houses with the results of a survey in apartments in multi-storey buildings.

View Article and Find Full Text PDF

The performance characteristics of a shadow-shield whole-body counter system with an array of four high-resolution germanium detectors using whole-body and organ-specific (lungs, liver, head, knee and thyroid) physical phantoms are described. Detection efficiency and minimum detectable activities for selected radionuclides and several measurement configurations are presented. Results demonstrate that the system meets the requirements for direct radio bioassay and that detection efficiency and minimum detectable activities are similar in magnitude to other whole-body (or organ) counting systems installed in fully shielded structures.

View Article and Find Full Text PDF

Infections caused by pyogenic streptococci are commons in pediatric ages. However, in the last decades there has been an increase in the isolation of no A or B Streptococci. We report a case of a 6 years old girl, who presents fever for 5 days and erythroderma.

View Article and Find Full Text PDF

The free-surface Liquid-Lithium Target, recently developed at Soreq Applied Research Accelerator Facility (SARAF), was successfully used with a 1.9 MeV, 1.2 mA (2.

View Article and Find Full Text PDF

The average radon concentration in Israeli dwellings was assessed by combining the results of a 2006 radon survey in single-family houses with the results of a 2011 radon survey in apartments of multistorey buildings. Both surveys were based on long-term measurements using CR-39 detectors. The survey in multistorey buildings was intended to assess the influence of recent practices in the local building industry on the radon concentrations.

View Article and Find Full Text PDF

Relatively elevated concentrations of naturally occurring radium isotopes ((226)Ra, (228)Ra and (224)Ra) are found in two main aquifers in the arid southern part of Israel, in activity concentrations frequently exceeding the limits set in the drinking water quality regulations. We aimed to explore the environmental implications of using water containing Ra for irrigation. Several crops (cucumbers, melons, radish, lettuce, alfalfa and wheat), grown in weighing lysimeters were irrigated at 3 levels of (226)Ra activity concentration: Low Radium Water (LRW)<0.

View Article and Find Full Text PDF

Until recently, the optimal work-up of patients with stable coronary artery disease (CAD) was based on non-invasive functional tests. Coronary CTA (CCTA) now challenges this standard work-up due to its efficacy to exclude significant coronary artery disease. Current indications for CCTA include symptomatic patients with intermediate pre-test probability of CAD with altered ECG (LBBB, repolarization abnormalities) rendering stress tests useless or patients unable to achieve sustained stress effort, and patients with indeterminate or uninterpretable results on ischemic work-up.

View Article and Find Full Text PDF

High levels of naturally occurring and carcinogenic radium isotopes have been measured in low-saline and oxic groundwater from the Rum Group of the Disi sandstone aquifer in Jordan. The combined 228Ra and 226Ra activities are up to 2000% higher than international drinking water standards. Analyses of the host sandstone aquifer rocks show 228Ra and 226Ra activities and ratios that are consistent with previous reports of sandstone rocks from different parts of the world.

View Article and Find Full Text PDF

In this experimental work the co-precipitation procedure is used to prepare samples of water for measurement of their gross alpha concentration. It has been suspected that total dissolved solids (TDS) in the water influence the results of radioactivity counting. The dissolved solids may influence the chemical procedures of sample preparation or the detection and counting of the alpha particles emitted by the radionuclides in the drinking water.

View Article and Find Full Text PDF

The Organic Bound Tritium (OBT) amount in the body may induce changes in the evaluation of the internal exposure to tritium, due to its different retention time relative to HTO. OBT measurements for urine are not performed routinely, mainly because of the lengthy work needed in preparation of the samples, when using the standard oxygen combustion method. A simpler and more rapid method based on liquid scintillation counting (LSC) was employed, and an evaluation was performed to check its suitability for urine samples.

View Article and Find Full Text PDF

The 3He(4He,gamma) 7Be reaction plays an important role in determining the high energy solar neutrino flux and in understanding the abundances of primordial 7Li. This Letter reports a new precision measurement of the cross sections of this direct capture reaction, determined by measuring the ensuing 7Be activity in the region of Ec.m.

View Article and Find Full Text PDF

The recoil fragments from an alpha-emitting source may cause significant detector contamination. The simplest method to avoid the problem is to use a source coating. The influence of Mylar film coatings of different thickness on the resolution, efficiency and minimum detection level of an alpha spectrometry system was investigated.

View Article and Find Full Text PDF

Considerable errors in the activity determination in lungs can be induced for the case of a "hot spot". Modern lung counter systems use several HPGe detectors, and the count rate ratios of the detectors can be used to locate the "hot spot" and apply correction algorithms. Some criteria for location determination of a point source in the lungs were investigated, and it is shown that an average error of up to about 10% can be achieved.

View Article and Find Full Text PDF

The 7Be(p,gamma)8B reaction plays a central role in the evaluation of solar neutrino fluxes. We report on a new precision measurement of the cross section of this reaction, following our previous experiment with an implanted 7Be target, a raster-scanned beam, and the elimination of the backscattering loss. The new measurement incorporates a more abundant 7Be target and a number of improvements in design and procedure.

View Article and Find Full Text PDF

The algorithm used to calculate a minimum detectable activity (A(D)) of an environmental volume sample measured by gamma-ray spectrometry was modified and adapted for in situ measurements performed at the standard 1 m height above ground. AD values of target radionuclides were determined from the in situ spectra collected at two disparate sites. A linear relationship between the two sets of A(D)s was found and the ratio between these two sets is equal to the square root of the ratio of the two respective absorbed dose rates measured at the sites at 1 m height.

View Article and Find Full Text PDF

Because of the increased complexity of modern pacemakers, pacemaker follow-up visits in specialized centers become more and more indispensable. In this study, the results of 15,000 outpatient visits to the cardiac pacing center between the years 1983-1985 are presented. In most cases (92.

View Article and Find Full Text PDF

The authors describe a computer system with details of the hard ware and filing organisation. The sophistication and originality of the programme makes it a multipurpose tool base on a condensed dictionary. Its uses may be summarised under three headings: --The upkeep of medical case notes, a very successful application, resulting in improved safety in the long term follow-up of pacemaker patients.

View Article and Find Full Text PDF

Left ventricular relaxation as opposed to contraction, was studied by recordings of left ventricular pressure and its first derivation in primary hypertrophic cardiomyopathy without obstruction (25 cases, Group II) in primary dilated cardiomyopathy (33 cases, Group III) and in normal subjects (22 cases, Group I). Simultaneous recording of the pressure, the first derivation and intraventricular and intraaortic phonocardiogrammes showed the significance of certain features of the tracings and allowed a simplified protocol: ventricular relaxation was then defined from the pressure tracing (high fidelity recording) and its first derivation. The onset of isovolumic relaxation corresponded to the point of inflection on the descending part of the first derivation tracing, preceding its negative peak by an average of 0.

View Article and Find Full Text PDF