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PURPOSE OF THE STUDY Cementless stems in highly dysplastic hips are considered to increase the risk of femoral fracture and associated morbidity. Several authors speculated to use prophylactic cabling in this patient group to prevent intraoperative fractures. This study aims to reveal objective results regarding the perioperative complications in a large and consecutive patient group with respect to use of prophylactic cabling. MATERIAL AND METHODS A retrospective comparative study was planned. A total of 122 consecutive patients with dysplastic hips of Crowe type 3 or 4, operated on with total hip arthroplasty (THA) and shortening osteotomy using a rectangular femoral stem were included. Patients were stratified according to use of a diaphyseal prophylactic cerclage cable. Perioperative complications were recorded. Clinical outcome was measured in terms of Harris Hip Score and Visual Analog Scale (VAS) for pain. All results were compared between the groups. RESULTS The mean follow-up time was 27 months. Two (2%) versus five (14%) patients had a fracture at the diaphyseal level in cabled versus non-cabled groups. Difference between groups was statistically significant (p=0.01). Relative risk of fracture in case of a non-cabling was 5.8 (p=0.03). Eleven (9%) patients had a non-displaced fracture at the metaphyseal level. No significant differences were detected with respect to preoperative clinical outcome scores or change in these scores between groups. CONCLUSIONS Femoral diaphyseal fracture rates are low when cementless, rectangular stems are used in dysplastic high riding hips. Prophylactic cerclage cabling further decreases the fracture risk and eases treatment in case of a fracture without causing additional complications and therefore is recommended. Key words: intraoperative fracture, periprosthetic fracture, total hip arthroplasty, cerclage cabling, developmental hip dysplasia, transverse shortening osteotomy.

Background Challenges must be handled in an integrated manner when addressing food security and climate change. More efficient designs for food production systems, as well as their logistics, are needed in order to increase food production and to reduce emissions intensity. Specifically, any enhancements done on this purpose would contribute to mitigating climate change. Five important dimensions are being considered in smart agriculture: food security, availability, accessibility, utilization, and stability. Scope and approach Food supply-demand chain can seriously be effected by uncontrolled population growth. Thus, any perspective to solve these uncontrolled conditions can have a positive impact. Especially giving emphasis on reduction of food losses via expoloring various ways of production, or increasing productivity, or ensuring food security are effective ways for solutions. For example, the use of solar drying for agricultural, marine or meat products is very important for preservation, thus minimizing food losses. However, traditional sun drying is a relatively slow process. Also, the product quality worsens due to several factors: microorganism growth, enzymatic reactions, insect infestations. It is known that utilizing solar energy involves several factors that need attention. Thus, a lot of effort is directed toward improving solar energy technology for drying processes. Key findings and conclusion This study presents a smart agriculture design for drying using low cost and highly-efficient solar selective absorber. The system is based on an air heating flat plate solar absorber. Levelized cost of heat (LCOH) for the prototype using solar renewable energy is calculated and compared with the fossil fuel energy sources; natural gas, electricity, and liquified petroleum gas (LPG). In addition; a comparison of the costs for air collectors using various selective absorbers; unglazed or glazed, is presented. It is shown that solar energy, in the long run, will be more advantageous compared to fossil fuels., Agricultural science; Chemical engineering; Energy Engineering; Food technology; solar selective absorbers; solar energy; LCOH

The distributions of 226Ra, 232Th, 40K and 137Cs activity concentrations were determined using a high-purity germanium detector in uncultivated surface soil samples collected from Zonguldak. The range of 226Ra, 232Th, 40K and 137Cs activity concentrations varied from 10.5 ± 2.0 to 98.0±4.3 Bqkg-1 (mean value 28.8 ±4 Bqkg-1), from 12.9 ± 3.4 to 53.2 ± 5.1 Bqkg-1 (mean value 29.6 ± 3 Bqkg-1), from 190 ± 22 to 808 ± 43 Bqkg-1 (mean value 395 ± 31 Bqkg-1) and from < 0.5 to 47.1 ± 3.8 Bqkg-1 (mean value 12.5 ± 2 Bqkg-1), respectively. In addition, the mean outdoor absorbed dose rates in air (terrestrial, terrestrial+cosmic), annual effective dose equivalent, radium equivalent activity and external hazard index were found to be 48 nGy h-1 (terrestrial), 56 nGy h-1 (terrestrial+cosmic), 58 µSvy-1, 101 Bqkg-1 and 0.27, respectively. The evaluated excess lifetime cancer risks (ELCRs) varied from 0.13 × 10-3 to 0.36 × 10-3 with a mean value of 0.20 × 10-3., Firat University Scientific Research Projects Management Unit: 2013-76962555-01, The authors wish to thank Scientific Research Projects Unit of Bülent Ecevit University (Project No: 2013-76962555-01)

The radon concentrations in the groundwater, tap water samples and soil gases of the residential areas and forested lands of Uludağ were measured to research on the dynamics of low-high radon levels over the various rocks types found in this area. Besides, the annual effective doses for groundwater and tap waters were calculated and compared with the recommended dose value by the World Health Organization (WHO) to evaluate the health risk of inhabitant. The radon concentrations in water samples for the wet and dry seasons were found in the ranges of 0.17 ± 0.09 - 195.64 ± 6.87 Bq l-1 (median value of 5.13 Bq l-1) and 0.04 ± 0.01 - 199.24 ± 6.54 Bq l-1 (median value of 4.33 Bq l-1), respectively. Elevated radon concentrations were measured in the waters draining through igneous rocks (granite and granodiorite), known as uranium-rich rocks. The average radon and thoron concentrations of soil gases were found to be in the ranges of 0.65 ± 0.01 – 199.66 ± 3.27 kBq m-3 and 4.36 ± 0.36 – 245.9 ± 7.26 kBq m-3, respectively. The highest and lowest radon and thoron concentrations in soil gases were observed in the granitic area and in scree region, respectively.

Solid state nuclear track detectors have been applied in di erent studies including nuclear physics, particle physics, archaeology etc. Makrofol, a particular group of thermoplastic polymers, is used for radon detection. High background track numbers in the foils cause big uncertainties for places where the radon concentrations are quite low. Therefore, it is of great importance to lower the background track signal as much as possible, without reducing the sensitivity of the foils. The present study reports track density and sensitivity of Makrofol-DE after thermal annealing. The unexposed foils were heated at temperatures ranging from 110 ◦C to 140 ◦C for 10 min with the aim of observing changes in the number of background tracks. As a result a reduction in the background track density was observed. In order to observe the change in the sensitivity, pre-heated and unheated foils were exposed to alpha radiation in a radon chamber. At the temperatures of 110, 120, and 130 ◦C, the track density in the heated and unheated exposed foils is quite similar. An increase was observed in the track density in heated exposed foils at 140 ◦C.

This study presents an analytic formula for calculation of the coherent attenuation coefficients of gamma rays for 100 elements in the energy range from 0.01 to 3 MeV. The analytic formula is based on WinXCOM. Comparisons were made of the analytic coherent attenuation coefficients with the coherent attenuation coefficients calculated with the WinXCOM. The results obtained with the analytic approach agree well with those calculated with the WinXCOM.

The distributions of (226)Ra, (232)Th, (40)K and (137)Cs activity concentrations were determined using a high-purity germanium detector in uncultivated surface soil samples collected from Bursa. The range of (226)Ra, (232)Th, (40)K and (137)Cs activity concentrations varied from 10±1 to 61±3 Bq kg(-1) (mean value 25±3 Bq kg(-1)), from 12±1 to 50±2 Bq kg(-1) (mean value 26±3 Bq kg(-1)), from 257±5 to 1010±11 Bq kg(-1) (mean value 435±44 Bq kg(-1)) and from 1.01±0.07 to 48.97±0.54 Bq kg(-1) (mean value 8.52±2.59 Bq kg(-1)), respectively. In addition, the mean outdoor absorbed dose rates in air, annual effective dose equivalent, radium equivalent activity and external hazard index were found to be 45 nGy h(-1), 56 μSv y(-1), 96 Bq kg(-1) and 0.26, respectively. The gross beta activity concentrations were determined using a Tennelec LB 1000-PW detector. The range of gross beta activity concentrations varied from 46±9 to 1199±113 Bq kg(-1) with a mean value of 541±19 Bq kg(-1).

Bu çalışma, 4-8 Şubat 2010 tarihlerinde İstanbul[Türkiye]'da düzenlenen 2. World Conference on Educational Sciences (WCES-2010)'da bildiri olarak sunulmuştur. The paper describes liquid phase epitaxial growth and characterization of the GaSb- and InAs-related materials for the photodiodes and thermophotovoltaic applications. It was shown that doping of the melt with holmium results in obtaining the high purity GaInAsSb and InAs layers. The passivation with the 1 M Na2S aqueous solution makes it possible to prepare flat growth surfaces of GaSb(1 0 0) and InAs(1 0 0) substrates after annealing. A reproducible technique has been developed for fabrication of the high-efficiency GaInAsSb/GaAlAsSb and InAs/InAsSbP photodiodes with the long-wavelength photosensitivity edge of 2.4 and 3.8 mu m, respectively. Room temperature detectivity in the spectral peak reaches D* = (0.8-1.0) x 10(11) W-1 cm Hz(1/2) for the GaInAsSb/GaAlAsSb photodiodes and D* = (3.0-5.0) x 109 W-1 cm Hz(1/2) for the InAs/InAsSbP devices. We have adapted the technology for thermophotovoltaic cells operating at an emitter temperature of 1000-1700 degrees

In the present work, the effect of ozone treatments on the structural properties of soybean oil (SBO) and hazelnut oil (HO) were investigated. The study presents the findings and results about the oxidation of HO and SBO with ozone, which has not been fully studied previously. The HO and SBO were treated with ozone gas for 1, 5, 15, 30, 60, 180 and 360 min. The ozone reactivity with the SBO and HO during the ozone treatment was analyzed by 1H, 13C NMR, FTIR and GC. The iodine value, viscosity and color variables (L*, a* and b*) of untreated and ozone treated oils were determined. Reaction products were identified according to the Criegee mechanism. New signals at 5.15 and 104.35 ppm were assigned to the ring protons of 1,2,4- trioxolane (secondary ozonide) in the ozonated oils in 1H and 13C NMR, respectively. Ozonated oils exhibited peaks at 9.75 and 2.43 ppm in 1H and NMR, which corresponded to the aldehydic proton and α-methylene group and to the carbonyl carbon, respectively. The peak at 43.9 ppm in 13C NMR was related to the α-methylene group and to the carbonyl carbon. The new signals formed in the ozonation process gradually increased with respect to ozone treatment time. After 360 min of ozone treatment, the carbon-carbon double bond signal, which belongs to the unsaturated fatty acids, disappeared completely in the spectrum. An increase in viscosity, a decrease in iodine value and a dramatic reduction in b* of the oil samples on (+) axis were observed with increased ozone treatment time. En el presente trabajo se investigó el efecto de tratamientos con ozono sobre las propiedades estructurales de aceites de soja (SBO) y avellana (HO). El estudio muestra hallazgos y resultados sobre la oxidación de HO y SBO con ozono que no se habían presentado previamente. Los aceites HO y SBO son tratados con ozono gaseoso durante 1, 5, 15, 30, 60, 180 y 360 min. La reactividad del ozono con SBO y HO durante el tratamiento se analizó mediante 1H, 13C NMR, FTIR y GC. Se midieron las variables: índice de yodo, viscosidad y color (L *, a * y b *) de los aceites no tratados y tratados con ozono. Los productos de reacción se identificaron de acuerdo con el mecanismo de Criegee. Se asignaron nuevas señales a 5,15 y 104,35 ppm a los anillos protónicos de 1,2,4-trioxolano (ozónido secundario) en aceites ozonizados en 1H y 13C RMN, respectivamente. Los aceites ozonizados también mostraron picos a 9,75 y 2,43 ppm en 1H NMR correspondientes al protón aldehídico y al grupo α-metileno, respectivamente. El pico a 43,9 ppm en 13C RMN se relacionó con el C carbonilo del grupo α-metileno. Las nuevas señales formadas en el proceso de ozonización aumentaron gradualmente con respecto al tiempo de tratamiento con ozono. Después de un tratamiento de 360 minutos con ozono, la señal del doble enlace C=C que pertenece a los ácidos grasos insaturados desapareció por completo en el espectro. Se observó un aumento en la viscosidad, una disminución en el índice de yodo, una reducción drástica en b* de muestras de aceite en el eje (+) con el aumento del tiempo de tratamiento con ozono.

Bu çalışma, 25-27 Şubat 2009 tarihleri arasında Vienna[Avusturya]’da düzenlenen 22. Seminar on Activation Analysis and Gamma Spectroscopy’da bildiri olarak sunulmuştur. This paper presents results on the angular distribution of Compton scattering of 662 keV gamma photons in both forward and backward hemispheres in copper medium. The number of scattered events graph has been determined for scattered gamma photons in both the forward and backward hemispheres and theoretical saturation thicknesses have been obtained using these results. Furthermore, response function of a 51 x 51 mm Nal(Tl) detector at 60 degrees angle with incoming photons scattered from a 10mm thick copper layer has been determined using Monte Carlo method.

Radio-frequency (HF) quasi-potential Φ in the field of the space charge region of contact of a metal–semiconductor is explored. At the frequency, ω, greater frequency plasma fluctuations ω0 HF quasi-potential is positive, but at frequencies ω < ω0 quasi-potential Ph is negative. VAC and Schottky barrier with provision for HF quasi-potential are calculated. It is shown that HF gives an essential contribution on EMF hot carriers when frequency of wave is less in electronic gas fluctuations in layer potential barrier.

The LB 1000-PW detector is mainly used for determining total alpha, beta and gamma activity of low activity natural sources such as water, soil, air filters and any other environmental sources. Detector efficiency needs to be known in order to measure the absolute activity of such samples. This paper presents results on the total gamma counting efficiency of a Phoswich detector from point and disk sources. The directions of photons emitted from the source were determined by Monte Carlo techniques and the true path lengths in the detector were determined by analytical equations depending on photon directions. Results are tabulated for various gamma energies.

We have studied the electrical characteristics of photodiodes based on p-GaSb/p-GaInAsSb/N-GaAlAsSb heterojunctions and investigated the mechanisms of current transfer in these heterostructures at various temperatures. A comparison of the theoretical results and experimental data showed that the tunneling charge transfer mechanism dominates at low temperatures (T < 150 K) under both forward and reverse bias conditions. The tunneling current becomes a determining factor at an electric field strength in the p-n junction of no less that 105 V/cm, which is related to a small bandgap width of the materials studied and low effective masses of electrons and holes.

Spring waters used as spas and their region may contain significant amounts of natural radionuclides. The main sources of exposure are the inhalation of radon and its decay products released from the water and soil and terrestrial gamma-radiation. In order to evaluate the potential risk of thermal regions in Bursa, located in the impact area of the NAF (North Anatolian Fault), radon and thoron concentrations in soil gas, radon concentrations in thermal waters and outdoor gamma radiation levels were measured in thermal regions that have different geological formations. The radon and thoron concentrations in soil-gas were found to vary from 2272 ± 121 to 245196 ± 3455 Bq m-3 and from 999 ± 218 to 178 848 ± 17 742 Bq m-3, respectively. The radon concentrations in thermal waters ranged from 0.99 ± 0.21 to 226.74 ± 2.51 Bq l-1 in the rainy season and from 0.26 ± 0.10 to 178.03 ± 12.86 Bq l-1 in the dry season. The measured outdoor gamma radiation levels varied from 38 to 180 nGy h-1. The gamma dose rates were found to be strong positively correlating with the radon and thoron concentrations in soil-gas. The radon and outdoor gamma radiation levels were observed to be a function of the geological formations of the area. © 2016 IOP Publishing Ltd.

It was well known that inhalation of high levels of radon can lead to lung cancer. Indoor radon concentration measurements were carried out in randomly selected 18 dwellings of Y ld r m county in Bursa, Turkey using Makrofol-DE Solid State Nuclear Track Detectors. The results of the radon measurements ranged from 13 to 98 Bq m−3, with as 42 Bq m−3 average value. The range of annual e ective dose was between 0.33 and 2.47 mSv y−1.

Color removal from neutralized sunflower oil was studied with different kinds of commercial bleaching earths. The effect of changes in time (25 and 35 min), temperature (80–125 °C), and bleaching earth dosage (0.1–0.9% by weight) on color, chlorophyll and carotene concentrations, and oxidation degree were investigated. To obtain adsorption curves from coloring compounds adsorbed onto activated bleaching earths, the Langmuir and Freundlich equations was used, the constant parameters and correlation coefficient R were calculated for each type of bleaching earth, and color changes were explained by both adsorption isotherms. It was observed that an increase in bleaching earth dosage decreases color. Its effect on oxidation state, however, is complex and related to both primary and secondary oxidation products. In addition, an increase in temperature seems to decrease chlorophyll and carotene adsorptions. Generally, time beyond equilibrium is considered useless for the removal of unwanted components. This study also confirms this claim and reveals that the peroxide value does not indicate the oxidation state of the oil completely.

ZnO film coated Co-based (2705 X) amorphous ribbons are prepared by the successive ionic layer adsorption and reaction technique. The influence of coating on giant magneto-impedance (GMI) has been investigated over a frequency range from 0.1 to 3.5 MHz and under a static magnetic field between -8 and +8 kA/m. The highest GMI ratio of 15.63% was obtained in the coated Co-based amorphous ribbons which is 80% higher than the sample without coating. The results indicate that the surface coating process plays an important role in the GMI effect.

It is known that for the study of low-energy gamma rays in the atmosphere, coherent scattering, incoherent scattering, photoelectric effect, and total coherent and incoherent cross-sections are needed. In this study, a number of interpolation functions are derived to relate energy to cross-section continuously.

The radon concentrations in soil-gas and water samples (in the form of springs, catchment, tap, thermal) used as drinking water or thermal were measured using a professional radon monitor AlphaGUARD PQ 2000PRO. The measured radon concentrations in water samples ranged from 0.32 to 88.22 Bq l-1. Most of radon levels in potable water samples are below the maximum contaminant level of 11 Bq l-1 recommended by the US Environmental Protection Agency. The calculated annual effective doses due to radon intake through water consumption varied from 0.07 to 18.53 µSv y-1. The radon concentrations in soil gas varied from 295.67 to 70 852.92 Bq m-3. The radon level in soil gas was found to be higher in the area close to the formation boundary thrust and faults. No correlation was observed between radon concentrations in groundwater and soil gas. Also, no significant correlation was observed between soil-gas radon and temperature, pressure and humidity. The emanation of radon from groundwater and soil gas is controlled by the geological formation and by the tectonic structure of the area. © The Author 2013. Published by Oxford University Press. All rights reserved.

The spectral distribution of multiply scattered gamma ray energy in water is determined by the Monte Carlo sampling technique in the energy range 0.5 - 1.6 MeV. It is found that the energy for which the scattered photon number is a maximum, is related to the source energy and this is in agreement with studies made by Minato for a point source in different media.

Photoelectric absorption is an interaction in which an incoming gamma ray virtually transfers all of its energy to an atomic electron, usually the most tightly bound K-shell electron of an atom. This paper uses the Win XCOM computer code as a reference base. We found analytical photoelectric attenuation coefficients for researchers using the Monte Carlo simulation program for Z is an element of [1; 100] and E is an element of [10 keV; 3MeV]. We define a photoelectric effect operator and coefficient operators and a series for photoelectric absorption. We have calculated two polynomial coefficient operators for use with XCOM for photoelectric absorption. We determined 14 energies and atomic number limits for elements, and we find that they are accurate limits of photoelectric absorption for fitting with XCOM.

Concentration of Rn-222 was determined in selected natural spring and tap water samples collected during spring and summer seasons from Kastamonu, Turkey. The aim of this work was to produce a map of the radon concentrations in water sources of the province and to determine any potential radiological risk for the local population. Radon measurements were performed by an AlphaGUARD radon gas analyser. The average radon concentrations were found to vary from 0.39 +/- 0.02 to 12.73 +/- 0.39 Bq 1(-1) for natural springs and from 0.36 +/- 0.04 to 9.29 +/- 0.45 Bq 1(-1) for tap water in spring, from 0.50 +/- 0.09 to 19.21 +/- 1.00 Bq 1(-1) for natural springs and from 0.31 +/- 0.03 to 13.14 +/- 0.38 Bq 1(-1) for tap water in summer. Furthermore, the results are compared with international recommendations and concentrations reported for other countries. Doses resulting from the consumption of these waters were calculated. The effective dose equivalents due to the intake of the Rn-222 present in these waters are expected to range from 0.93 to 32.54 mu Sv y(-1) in summer and from 0.80 to 49.09 mu Sv y(-1) in spring.

(222)Rn measurements in water samples collected from 27 wells and 19 taps that were supplied from the investigated wells were conducted using the AlphaGUARD PQ 2000PRO radon gas analyser at sites across several geologic formations within the city of Bursa, Turkey. The measured radon concentrations ranged from 1.46 to 53.64 Bq l(-1) for well water and from 0.91 to 12.58 Bq l(-1) for tap water. Of the 27 sites sampled, only 7 had radon levels above the safe limit of 11.1 Bq l(-1) recommended by the USEPA. In general, all determined concentrations were well below the 100 Bq l(-1) revised reference level proposed by the European Union. These values of radon concentrations in water samples are compared with those reported from other countries. Doses resulting from the consumption of these waters were calculated. The minimum and the maximum annual mean effective doses due to (222)Rn intake through water consumption were 0.02 µSv a(-1) and 1.11 µSv a(-1), respectively.

The asphaltene has been obtained from asphalt cement with penetration grade 60, which is extracted from crude Libya petroleum. The elemental composition and some structural properties of the asphaltene samples are determined by various methods, such as SEM, infrared spectroscopy, and X-ray analysis. Some experiments are performed on 1H dynamic nuclear polarization (DNP) in a number of asphaltene suspensions in organic solvents. The frequency dependence of the DNP enhancement under conditions of weak EPR saturation in a low magnetic field is obtained and interpreted as the EPR line shape of some free radicals present in the samples.

A Copper oxide (CuO) film has been grown on a surface of Co-based amorphous ribbon using chemical successive ionic layer adsorption and reaction technique, at room temperature and atmosphere pressure. The influence of coating and width of ribbon on giant magneto impedance have been investigated over a frequency range from 0.1 to 3 MHz and under a static magnetic field between −8 and +8 kA/m. The results showed that Co-based amorphous ribbons, which are coated CuO film, have a significant effect on the magnitude and operation frequency for the giant magneto impedance effect as compared to the samples without coating. The highest giant magneto impedance effect was found to be 14.90 on 5 mm width coated ribbon, which is 60% higher than the sample without coating. A surface observation of these samples has been carried out by an atomic force microscope. The AFM images reveal the difference between surfaces of coated and as-cast sample.

The main objective of the present study is to determine the type of environmental contamination in lichens in Gokceada Island in the Northern Aegean Sea in Turkey. We used two different lichen species Cladonia foliacea and Ramalina pollinaria. In the first part of the investigation, the beta activities of lichens have been measured by using a TENNELEC LB 1000-PW detector. The range of beta activity values was between 607 ± 30 and 308 ± 12 Bq/kg for C. foliacea lichens collected from around Tuz Lake and values for R. pollinaria lichens were found to be 740 ± 25 and 541 ± 17 Bq/kg. The second part of the study was concerned with the gamma spectra of the lichen samples measured by using HpGe detector. 137Cs, 134Cs, 40K, 232Th, 226Ra radionuclides were found in C. foliacea collected from around Tepekoy and in R. pollinaria from around Tuz Lake. When these two types of lichens were compared, it was found that R. pollinaria contain more radionuclides. In order to compare and determine which of these lichens act as a better bioaccumulator, K, Mn, Zn, Rb, Sr, Ba and Pb metal content were determined by using Energy Dispersive X-ray fluorescence spectrometry. It was found that C. foliacea collected more Mn and Sr when compared to R. pollinaria.

This paper presents results on the total gamma counting efficiency of a NaI(Tl) detector from point and disk sources. The directions of photons emitted from the source were determined by Monte-Carlo techniques and the photon path lengths in the detector were determined by analytic equations depending on photon directions. This is called the hybrid Monte-Carlo method where analytical expressions are incorporated into the Monte-Carlo simulations. A major advantage of this technique is the short computation time compared to other techniques on similar computational platforms. Another advantage is the flexibility for inputting detector-related parameters (such as source–detector distance, detector radius, source radius, detector linear attenuation coefficient) into the algorithm developed, thus making it an easy and flexible method to apply to other detector systems and configurations. The results of the total counting efficiency model put forward for point and disc sources were compared with the previous work reported in the literature.

Mosses are one of the most widely used procedures to determine via plant of radioactive contamination. The high concentrating capacity of mosses may be used as bioindicator of environmental radioactive contamination. In this study, the mosses were collected in region of Katirli Mountain in northwestern Turkey, activities were determined using TENNELEC LB 1000‐PW detector. Samples of mosses growing on soil, rock, and tree bark were collected.

The energy distributions of beta particles which penetrated a certain matter thickness were studied experimentally and theoretically by using a Surface barrier solid state detector. A valid theoretical expression based on average values between energy and distance traveled during the slowing down of the electron wits obtained. Two analytical expressions were proposed; one for the energy distribution of monoenergetic electrons which penetrated it certain matter thickness, and one for the response function in the detector for monoenergetic electrons detected with its entire energy. Response functions of the detector for beta particles emitted from Tl-204 isotope which penetrated a certain matter thickness were obtained for two different aluminum thicknesses, and the results were discussed by comparing with experimental energy spectra. (c) 2005 Elsevier B.V. All rights reserved.

To investigate the attitudes and practices of breastfeeding mothers regarding fasting in Ramadan.Cross-sectional observational survey.Well-child care clinic at Ankara University Medical School and a health station serving an impoverished population in Ankara, Turkey.Breastfeeding mothers of infants aged 12 months or younger.Fasting during Ramadan.Of the 164 participating mothers, 61 (37%) were from the health station and 103 (63%) from the university clinic. Most mothers were older than 25 years of age (55%), had more than primary school education (64%), a single child (53%), were living in a nuclear family setting (70%), supplementing breastfeeding (73%) and fasting (52%). Among the 129 mothers of infants aged 6 months or younger, 22% perceived a decrease in their breast milk and 23% an increase in the amount of solid supplements the infant was receiving. Belief that breastfeeding mothers should fast (RR = 6.45, 95% CI: 2.44-17.06), that fasting does not decrease breast milk (RR = 6.24, 95% CI: 1.85-21.05), receiving well-child care at the health station (RR = 3.14, 95% CI: 1.33-7.44), giving supplements (RR = 2.82, 95% CI: 1.09-7.27) and having multiple children (RR = 2.78, 95% CI: 1.23-6.28) were associated with fasting, in a logistic regression model.Fasting by breastfeeding mothers of infants is common during Ramadan, and rates are affected by beliefs of mothers on the effects of fasting on breastfeeding. We believe that child health care providers need to be knowledgeable about religious and cultural phenomena, study the effects of Ramadan fasting and form links with Islamic teachings to find religiously and culturally appropriate methods to combat the possible unfavourable effects for infants and children.

Projected ranges of electrons in some elemental solids and gases of atomic number between 4 and 18 (Be, C, N, Na, Al, Si and Ar) have been obtained by a method based on a discontinuous slowing down model in the slowing down of an electron from an certain energy E to a minimum energy E min. The incident energies of electrons considered are from 0.06 to 3 MeV. The obtained projected ranges of electrons have been compared to the values in previous work.