Respuesta de termoluminiscencia del sistema de vidrio anfitriónde sílice borato de zinc (ZBS) irradiado con electrones y fotones

Introduction: Glass phosphors are broadly used to determine patient doses in radiation diagnostic and radiotherapy because of their good features, the dose ranges of interest are approximately0.1 -100 mGy for clinical x-ray diagnostics, and 1-5Gy for radiotherapy. Materials and Methods: Borate silica glass samples were prepared using melt quenching technique, XRD analysis confirms that the glass system is amorphous (non- crystalline). TL properties of glass were investigated such as optimum concentration, heating rate, and annealing procedure. The optimum glass samples of 45ZnO-45B 2O3-10SiO2 are used as glass radiation dosimeter. The samples were irradiated using 6MeV and 6MV photon beams in adose range (0.5-4) Gy. Results and Discussion: There is single and wide thermoluminescence glow curve that offering with maximum intensity at about 165 oC. Linear dose-response behavior has been observed in this dose range for both irradiation electron and photon beam. Sensitivity and minimum detectable dose have been found. The sensitivity of 6MeV is 1.7 greater than the sensitivity of 6MV photon energy. Conclusions: The results point out that this glass has the potential to be used as an electron and photon radiation dosimeter

A serological study of brucellosis in camels south of Kirkuk, Iraq

A study of the prevalence of antibodies to camel brucellosis has been carried out in the south of Kirkuk city during March 2011. A total of 66 camels (6 male, 60 female) involved in this study with age between 6 months to 22 years. Blood samples were collected from jugular vein and the sera samples were screened by using Rose Bengal Plate Test (RBPT). The sera that were positive by using RBPT have been tested again by using the 2-Mercaptoethanol (2ME) test. The results of this study revealed that two camels from 66 camels (3.03%) were seropositive for brucella antibodies in South of Kirkuk city

Effect of Clay as a Nanomaterial on Corrosion Potential of Steel Reinforcement Embedded in Ultra-High Performance Concrete

The effect of clay as nanomaterial or nanoclay (NC) on corrosion potential of steel reinforcement embedded in ultra-high performance concrete (UHPC) due to the early age properties of UHPC was investigated. In this present research, ordinary Portland cement (OPC) was partially replaced by NC at 1, 3, and 5 % by weight of cement to produce the nanoclayed UHPC. It is well recognized that the corrosion of steel reinforcement would affect the service life of the reinforced concrete structure performance. To overcome this problem, UHPC was benefited due to its superior characteristic in term of density and durability as compared to OPC concrete itself. In this present research, half-cell potential (HCP) was used to monitor and measure the corrosion potential of steel reinforcement embedded in UHPC and nanoclayed UHPC. Meanwhile, weight loss of corroded steel reinforcement and pH values of hardened UHPC and nanoclayed UHPC were also conducted as follows to the specific procedures. All the samples were immersed in 3 % sodium chloride solution up to 91 days of exposure. The results revealed that the corrosion activity of steel reinforcement embedded in UHPC with 5 % NC recorded the lowest corrosion potential readings compare to those UHPC. It is also shows that the pH value of concrete and weight loss of corroded steel reinforcement in UHPC alone is highest compared to UHPC incorporating different levels of NC. As regards to the results, it is revealed that replacing NC as a replacement to cement significantly enhanced the chloride penetration of nanoclayed UHPC. It is also indicated that the corrosion potential decreased with the increase of NC and as a result delayed the corrosion initiation

Monitoring and Modelling Morphological Changes in Rivers Using RS and GIS Techniques

River geomorphological investigation issues have received little attention in most countries of the world. Such processes become a pressing necessity due to climate change and anticipated events of extraordinary surges and dry seasons, which may debilitate the security of adjacent and downstream cities, particularly in locales that are exceedingly delicate and influenced by climatic changes. Al-Abbasia reach is a river that runs through the middle of the Euphrates River and is known for its numerous bends and meanders. The study of hydraulic structures such as barrages can provide important information about their influences on morphological processes in river reaches near the barrage upstream and downstream. Hydraulic analysis is made of the river behavior in u/s and d/s of hydraulic structures like barrages as a result of sediment deposition and erosion in u/s and d/s. A study, i.e., research on the impacts of the Abbassia barrage on the river system, has been conducted to address this issue using multi-temporal Landsat satellite data from 1976 to 2022 provided by the USGS. The study reach is located 5 kilometres upstream and 5 kilometres downstream of the Abbassia reach. Following the construction of the barrage, which had an impact on the sedimentation and geometry of the river, morphological variations took place in this part of the Al Abbassia reach. In this study, morphological changes throughout 49 years between 1976 and 2022 were investigated utilising remote sensing (RS) and geographic information system (GIS) approaches. Additionally, four image groups from three separate decades were used to perform change detection (1990–2000, 2000–2010, and 2010–2022). In this study, a monitoring system using Landsat-3 MSS: 1985, Landsat-5 TM: 1990, 1995, 2000, 2005, and Landsat-8 OLI: 2010, 2011, 2015, 2021, 2022 were employed to map river planform changes. The long-term comparison of this series of satellite images and historical maps for the period 1976–2022 indicates a continuation of change in the reach study with a rate of approximately 56, 33, 97, and 55% for upstream and 19%, 26%, 3%, and 45% for downstream for the width, area, deposition, and erosion, respectively. Furthermore, it is observed that there is a shift in river course within 200 m downstream of the barrage for the period of 1985–1990. The findings of this study, which monitor river morphological change at finer temporal and spatial resolutions, are crucial for promoting sustainable river management. They also aid in the investigation of river behaviour, which is necessary for providing the best management possible and overcoming the difficulties posed by this important research issue. Doi: 10.28991/CEJ-2023-09-03-03 Full Text: PD

The Effect of Sn(IV) Chlorin e6 on HepG2 Cancer Cell Lines

This research investigated the effect of Sn(IV) chlorin e6 dichloride trisodium salt photosensitizer on the viability of HepG2 cancer cell lines in vitro. The effect of light on the viability of cells without the photosensitiser and the toxicity of the photosensitiser in the absence of light were examined in this research. No toxic effects with the absence of light were found and no photodamge effect on the cells without the presence of photosensitiser. The effect of different concentrations of the photosensitiser with fixed light dose of 70 J/cm2 on the viability of HepG2 cancer cells were performed. Then, two concentrations 25 and 30 μg/ml were investigated at different light doses 60-100 J/cm2. The effect of the photosensitiser on the viability of HepG2 at different light doses and different concentrations was found to have low viability over concentrations of 25 μg/ml. This could be due to that the photosensitiser reached a saturated status after this concentration. Key words: PDT; Sn(IV) chlorin e6; liver cancer; phototoxicity; viability assa

Characterisation of cassava biopolymers and the determination of their optimum processing temperatures

This work reports the characterisation of cassava biopolymers. Moreover, the effects of processing temperature on the tensile properties and phase morphology of cassava biopolymers were investigated. Eight diff erent temperatures were selected as processing temperatures in sample preparation of the cassava biopolymers. Variance analysis justifies that 165 and 170°C are the optimum processing temperatures in producing maximum tensile properties. The present study reveals that the range of processing temperatures for cassava biopolymer was relatively lower as compared to the majority of the petroleum-based polymer. However, its low processing temperature makes this biopolymer has enormous potential in the development of fully biodegradable composites

Board diversity and total directors’ remuneration: evidence from an emerging market

This paper aims to examine the relationship between board diversity and total directors ’ remuneration in Malaysia. The authors have operationalised two variables to represent board diversity: the proportion of women directors on the board, to present gender diversity and the proportion of Bumiputras directors, to represent ethnic diversity. Design/methodology/approach – This study has used a panel least squares to test the relationship between board diversity and total directors ’ remuneration. Findings – Based on a 1,094 fi rm-year sample from 2007 to 2009, the authors found a positive and signi fi cant relationship between gender-diverse boards and remuneration, but a negative and signi fi cant relationship between ethnically diverse boards and remuneration. The interaction between gender and ethnically diverse boards results in a weaker negative relationship between ethnically diverse boards and remuneration with an increased presence of women directors. Finally, the authors found a positive and signi fi cant impact on remuneration when there are at least three women and three Bumiputras directors. The fi ndings are robust after controlling for corporate governance variables, institutional variables and fi rm characteristics. Research limitations/implications – The main implication of this fi nding is the positive effect of fi rms hiring more women in top management roles on remuneration. In addition, the negative effect of Bumiputras suggests that their role is to offer political expedience to the board and thus provide economies of scale through their status to the country. Originality/value – This study tests the effect of both gender and ethnicity simultaneously on directors ’ remuneration. Keywords Gender, Ethnicity, Corporate governance, Malaysia, Remuneration, Directors ’ remuneratio