25 research outputs found
Flexible optical chemical sensor platform for BTX
An in-plane flexible sensor platform for BTX detection was developed using low-cost patterning techniques and foil-based optical components. The platform was produced by a combination of laser patterning, inkjet printing and capillary filling. Key optical components such as lightguides, opticalcladding layers and metallic interconnections were realized on low cost substrates such as paper and PET. The sensing mechanism is based on the change in fluorescence spectra of a reporter dye, supported over a porous matrix. Detection limits down to 1 ppm for benzene, toluene and xylene have been measured. Response times down to a few seconds were observed for different gas concentrations
Dangerous chemical substances – Tools supporting occupational risk assessment
The assessment of risk associated with exposure to chemicals in the work environment is a task that still poses a lot of difficulties for the employers. At the same time the probability of adverse health effects faced by an employee as a result of such risks, and the related employer’s material losses should motivate employers to seek effective solutions aimed at assessing the risks and controling them to an acceptable level by the application of appropriate preventive measures. The paper presents examples of tools to assist the employer in the risk assessment associated with the presence of chemical agents in the workplace. Examples of guides, manuals, checklists and various interactive tools, developed in Poland and other European Union (EU) countries, as well as in countries outside the EU and international organizations are described. These tools have been developed to meet the current requirements of the law and allow a rough estimation of chemical risk and based on these estimates take further steps to improve working conditions and safety. Med Pr 2014;65(5):683–69
Study on Individual PAHs Content in Ultrafine Particles from Solid Fractions of Diesel and Biodiesel Exhaust Fumes
In order to characterize PAHs emissions of diesel engine fuelled with diesel and its blend (B20, B40). In the particle phase, PAHs in engine exhausts were collected by fiberglass filters using Electrical Low Pressure Impactor (ELPI) and then determined by a high performance liquid chromatography with a fluorimetric detector (HPLC-FL). The main content in exhaust gases from diesel engine, regardless the type of applied fuel, is constituted by the particles fraction of diameter <0.25 μm. Particles sized <0.25 μm constituted on average approximately 68% of particles in diesel exhaust gases and approx. 50% of particles emitted by biodiesel B20 and B40. When the B100 bioester additive was applied, the total emission of particles was reduced thus the volume of toxic substances adsorbed on them was lower. The analysis of chemical composition of <0.25 μm exhaust gas fraction showed that there were mainly 3- and 4-ring aromatic hydrocarbons in the exhaust gas of diesel fuel while in B40 single PAHs with the number of rings of 4 and 5 were detected. An application of ELPI permitted a further separation of <0.25 μm particle’s fraction and a real-time determination of interalia number, mass, and surface concentrations
Assessment of occupational exposure to the respirable fraction of crystalline silica produced in technological processes
Wśród form krystalicznej krzemionki (minerałów zbudowanych z ditlenku krzemu), które najpowszechniej występują w środowisku naturalnym i w środowisku pracy, są kwarc i krystobalit. Są one wykorzystywane w różnych gałęziach przemysłu, m.in. w branży ceramicznej, szklarskiej czy budowlanej, i stanowią poważne zagrożenie dla zdrowia pracowników. Frakcja respirabilna krzemionki krystalicznej (FRKK), która przedostaje się do obszaru wymiany gazowej płuc, wywołuje przewlekłe reakcje zapalne, następnie zmiany zwłóknieniowe tkanki płucnej i w efekcie pylicę krzemową, często prowadzącą do raka płuc. Zarówno pracodawcy, jak i osoby zarządzające bhp, mają duże trudności z interpretacją oraz stosowaniem przepisów prawnych dotyczących pomiarów stężeń FRKK (w celu oceny narażenia zawodowego) i klasyfikacji prac w narażeniu na respirabilny pył powstający w trakcie procesów technologicznych. Informacje przedstawione w artykule powinny pomóc w rozwiązywaniu tych problemów.Among the forms of crystalline silica (silicon dioxide minerals) that are most common in the natural and work environments are quartz and cristobalite. They are used in various industries, including in the ceramics, glass and construction industries and pose a serious health risk to workers. The respirable of crystalline silica (RCS), which penetrates into the gas exchange area of the lungs causes chronic inflammatory reactions, followed by fibrotic changes in the lung tissue and, as a result, silicosis pneumoconiosis, often leading to lung cancer. Both employers and health and safety managers have great difficulties with the interpretation and application of legal provisions concerning the measurement of RCS concentrations (for the purpose of occupational exposure assessment) and the classification of work involving exposure to respirable dust generated during technological processes. The information in this article should help you resolve these issues
Effects of genistein supplemented before or after irradiation on DNA injury in human lymphocytes in vitro
Background. Ionizing radiation (IR) carry adequate energy to ionize or remove electrons from an atom. Particles interact with water to produce reactive oxygen species (ROS). Genistein (GEN) is a naturally occurring phytoestrogen and the basic isoflavonoid in soybeans and soybean-enriched products and is believed to have the strongest antioxidant activity.
Objective. The study aimed at the investigation if application of GEN at different time prior or past irradiation may ameliorate or reduce injury of DNA in human lymphocytes.
Material and Methods. The isolated lymphocytes were exposed to X-irradiation (0.5; 1 Gy). GEN (1 µM/ml; 10 µM/ ml) was appended to attempts at various times prior or past irradiation (1 h prior, immediately prior, immediately past, 1 h past). We joined each X-rays dose with each GEN dose. After 1h of incubation DNA damages were examined using Comet assay.
Results. Combination of 1 µM/ml of GEN given 1 h before irradiation with low or high dose markedly decreased induced by irradiation DNA injury. Higher dose of GEN applied immediately before or after irradiation markedly extended the frequency of DNA injury generated by irradiation. The result of application 1 µM/ml GEN 1 h after irradiation was not significantly different compared to control. The effect of 1 Gy + 10 µM/ml GEN was not significantly lower compared to each agent alone.
Conclusions. Only a very low concentration of GEN applied before irradiation, may be considered as a potential radiomitigator/radioprotector. High doses of GEN work as a radiosentitizer and may potent the effects of radiotherapy
Radon – occurrence and impact on the health
Radon is noble, monatomic, radioactive, heavier than the air gas. It is colorless, odorless, tasteless. It exists in natural environment as a result of the decay of radium, and emits mainly alpha radiation and less beta radiation. Residential radon concentrations vary widely by geographic area. The higher concentration of radon is expected globally in the grounds where uranium, radium and thoron are present. Radon may gather in caves, tunnels, mines as well as in other lowestlying spaces, such as basements, and cellars. In accordance with Atomic Law (2000), the reference level for the average annual concentration of radioactive radon in rooms intended for human habitation is 300 Bq/m3. The most dangerous damages caused by ionizing radiation i.e. radon and its derivatives are changes to DNA, which may disturb the functions of cells and in the consequence lead to induction of cancer of respiratory tract, mainly of lungs and also leukaemia. So, the main consequence of exposure to high amount of radon are cancers of respiratory system. Radon enters the human organism mainly through inhaled atmospheric air. Moreover, radon significantly increased a risk of induction cancer in smokers and vice versa, smoking promotes the development of lung cancer after the exposure to radon and its derivatives.
Radon may also have beneficial effect on the human body. Therefore it is used in medicine; mainly in radonbalneotherapy i.e. bath treatments, rinsing the mouth and inhalation. Beneficial effects of radon confirms the validity of the theory of radiation hormesis, which assumes that low doses of radiation may stimulate the repair of DNA damage by activation of protective mechanisms, which neutralize free radicals
Karjeros kompetencijos svarba darbuotojų karjerai: turizmo sektoriaus žmogiškųjų išteklių valdymo aspektas
Šiandieniniame veiklos pasaulyje turizmo srities specialistų demonstruojama karjeros kompetencija gali jiems padėti išspręsti problemas, kylančias dėl karjeros siekių ir darbo rinkos galimybių. Tačiau nauji specialistai, ateinantys į darbo rinką, dažnai neturi gebėjimų, užtikrinančių karjeros kompetenciją. Skiriasi ir ją bei darbdavių nuomonės šiuo klausimu. Todėl svarbu išsiaiškinti tiek žmogiškųjų išteklių valdymo objektų, tiek ir subjektų požiūrį į naujų darbuotojų karjeros kompetenciją kaip prielaidą sėkmingai jų karjerai. Šiuo tyrimu siekiama įvertinti naujų turizmo sektoriaus darbuotojų karjeros kompetenciją darbdavių požiūriu. Tyrimo rezultatai atskleidė naujų turizmo srities specialistų turimus ir darbdavių pageidaujamus įgūdžius: įsidarbinamumą, efektyvų bendravimą ir savęs pažinimą. Tyrimas atskleidė ir darbdaviams svarbiausius žmogiškųjų išteklių karjeros kompetenciją užtikrinančius gebėjimus.In the modern business world, career competences manifested by tourism professionals could help them cope with the problems arising from individual career ambitions and challenges in the labour market. However, new professionals, joining the labour market often do not possess skills ensuring career competences. Opinions of employers and employees differ on this issue. Thus, it becomes essential to interpret attitudes of both objects and subjects of human resources management to new employees’ career competences as an assumption for their successful career. This research aims to evaluate career competences of new employees in tourism sector in regards to their employers. The research results disclose what skills newly recruited tourism professionals possess, and what skills employers desire to find in employees’ effective communication and seif-cognition factors. The research unfolds what human resources career competences skills occur as the most significant for the employers
Diet in the Prevention of Alzheimer’s Disease: Current Knowledge and Future Research Requirements
Alzheimer’s disease is a progressive brain disease that is becoming a major health problem in today’s world due to the aging population. Despite it being widely known that diet has a significant impact on the prevention and progression of Alzheimer’s disease, the literature data are still scarce and controversial. The application of the principles of rational nutrition for the elderly is suggested for Alzheimer’s disease. The diet should be rich in neuroprotective nutrients, i.e., antioxidants, B vitamins, and polyunsaturated fatty acids. Some studies suggest that diets such as the Mediterranean diet, the DASH (Dietary Approaches to Stop Hypertension) diet, and the MIND (Mediterranean-DASH Intervention for Neurodegenerative Delay) diet have a beneficial effect on the risk of developing Alzheimer’s disease