905 resultados para effects and impacts


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In this article, we compare two strategies for atherosclerosis treatment: drugs and healthy lifestyle. Statins are the principal drugs used for the treatment of atherosclerosis. Several secondary prevention studies have demonstrated that statins can significantly reduce cardiovascular events including coronary death, the need for surgical revascularization, stroke, total mortality, as well as fatal and non-fatal myocardial infarction. These results were observed in both men and women, the elderly, smokers and non-smokers, diabetics and hypertensives. Primary prevention studies yielded similar results, although total mortality was not affected. Statins also induce atheroma regression and do not cause cancer. However, many unresolved issues remain, such as partial risk reduction, costs, several potential side effects, and long-term use by young patients. Statins act mainly as lipid-lowering drugs but pleiotropic actions are also present. Healthy lifestyle, on the other hand, is effective and inexpensive and has no harmful effects. Five items are associated with lower cardiac risk: non-smoking, BMI ≤25, regular exercise (30 min/day), healthy diet (fruits, vegetables, low-saturated fat, and 5-30 g alcohol/day). Nevertheless, there are difficulties in implementing these measures both at the individual and population levels. Changes in behavior require multidisciplinary care, including medical, nutritional, and psychological counseling. Participation of the entire society is required for such implementation, i.e., universities, schools, media, government, and medical societies. Although these efforts represent a major challenge, such a task must be faced in order to halt the atherosclerosis epidemic that threatens the world.

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Findings on the effects of weather on health, especially the effects of ambient temperature on overall morbidity, remain inconsistent. We conducted a time series study to examine the acute effects of meteorological factors (mainly air temperature) on daily hospital outpatient admissions for cardiovascular disease (CVD) in Zunyi City, China, from January 1, 2007 to November 30, 2009. We used the generalized additive model with penalized splines to analyze hospital outpatient admissions, climatic parameters, and covariate data. Results show that, in Zunyi, air temperature was associated with hospital outpatient admission for CVD. When air temperature was less than 10°C, hospital outpatient admissions for CVD increased 1.07-fold with each increase of 1°C, and when air temperature was more than 10°C, an increase in air temperature by 1°C was associated with a 0.99-fold decrease in hospital outpatient admissions for CVD over the previous year. Our analyses provided statistically significant evidence that in China meteorological factors have adverse effects on the health of the general population. Further research with consistent methodology is needed to clarify the magnitude of these effects and to show which populations and individuals are vulnerable.

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Pancreatic cancer is the fourth leading cause of cancer death. Gemcitabine is widely used as a chemotherapeutic agent for the treatment of pancreatic cancer, but the prognosis is still poor. Berberine, an isoquinoline alkaloid extracted from a variety of natural herbs, possesses a variety of pharmacological properties including anticancer effects. In this study, we investigated the anticancer effects of berberine and compared its use with that of gemcitabine in the pancreatic cancer cell lines PANC-1 and MIA-PaCa2. Berberine inhibited cell growth in a dose-dependent manner by inducing cell cycle arrest and apoptosis. After berberine treatment, the G1 phase of PANC-1 cells increased by 10% compared to control cells, and the G1 phase of MIA-PaCa2 cells was increased by 2%. Whereas gemcitabine exerts antiproliferation effects through S-phase arrest, our results showed that berberine inhibited proliferation by inducing G1-phase arrest. Berberine-induced apoptosis of PANC-1 and MIA-PaCa2 cells increased by 7 and 2% compared to control cells, respectively. Notably, berberine had a greater apoptotic effect in PANC-1 cells than gemcitabine. Upon treatment of PANC-1 and MIA-PaCa2 with berberine at a half-maximal inhibitory concentration (IC50), apoptosis was induced by a mechanism that involved the production of reactive oxygen species (ROS) rather than caspase 3/7 activation. Our findings showed that berberine had anti-cancer effects and may be an effective drug for pancreatic cancer chemotherapy.

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(+)-Dehydrofukinone (DHF) is a major component of the essential oil of Nectandra grandiflora (Lauraceae), and exerts a depressant effect on the central nervous system of fish. However, the neuronal mechanism underlying DHF action remains unknown. This study aimed to investigate the action of DHF on GABAA receptors using a silver catfish (Rhamdia quelen) model. Additionally, we investigated the effect of DHF exposure on stress-induced cortisol modulation. Chemical identification was performed using gas chromatography-mass spectrometry and purity was evaluated using gas chromatography with a flame ionization detector. To an aquarium, we applied between 2.5 and 50 mg/L DHF diluted in ethanol, in combination with 42.7 mg/L diazepam. DHF within the range of 10-20 mg/L acted collaboratively in combination with diazepam, but the sedative action of DHF was reversed by 3 mg/L flumazenil. Additionally, fish exposed for 24 h to 2.5-20 mg/L DHF showed no side effects and there was sustained sedation during the first 12 h of drug exposure with 10-20 mg/L DHF. DHF pretreatment did not increase plasma cortisol levels in fish subjected to a stress protocol. Moreover, the stress-induced cortisol peak was absent following pretreatment with 20 mg/L DHF. DHF proved to be a relatively safe sedative or anesthetic, which interacts with GABAergic and cortisol pathways in fish.

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The monitoring and control of hydrogen sulfide (H2S) level is of great interest for a wide range of application areas including food quality control, defense and antiterrorist applications and air quality monitoring e.g. in mines. H2S is a very poisonous and flammable gas. Exposure to low concentrations of H2S can result in eye irritation, a sore throat and cough, shortness of breath, and fluid retention in the lungs. These symptoms usually disappear in a few weeks. Long-term, low-level exposure may result in fatigue, loss of appetite, headache, irritability, poor memory, and dizziness. Higher concentrations of 700 - 800 ppm tend to be fatal. H2S has a characteristic smell of rotten egg. However, because of temporary paralysis of olfactory nerves, the smelling capability at concentrations higher than 100 ppm is severely compromised. In addition, volatile H2S is one of the main products during the spoilage of poultry meat in anaerobic conditions. Currently, no commercial H2S sensor is available which can operate under anaerobic conditions and can be easily integrated in the food packaging. This thesis presents a step-wise progress in the development of printed H2S gas sensors. Efforts were made in the formulation, characterization and optimization of functional printable inks and coating pastes based on composites of a polymer and a metal salt as well as a composite of a metal salt and an organic acid. Different processing techniques including inkjet printing, flexographic printing, screen printing and spray coating were utilized in the fabrication of H2S sensors. The dispersions were characterized by measuring turbidity, surface tension, viscosity and particle size. The sensing films were characterized using X-ray photoelectron spectroscopy, X-ray diffraction, atomic force microscopy and an electrical multimeter. Thin and thick printed or coated films were developed for gas sensing applications with the aim of monitoring the H2S concentrations in real life applications. Initially, a H2S gas sensor based on a composite of polyaniline and metal salt was developed. Both aqueous and solvent-based dispersions were developed and characterized. These dispersions were then utilized in the fabrication of roll-to-roll printed H2S gas sensors. However, the humidity background, long term instability and comparatively lower detection limit made these sensors less favourable for real practical applications. To overcome these problems, copper acetate based sensors were developed for H2S gas sensing. Stable inks with excellent printability were developed by tuning the surface tension, viscosity and particle size. This enabled the formation of inkjet-printed high quality copper acetate films with excellent sensitivity towards H2S. Furthermore, these sensors showed negligible humidity effects and improved selectivity, response time, lower limit of detection and coefficient of variation. The lower limit of detection of copper acetate based sensors was further improved to sub-ppm level by incorporation of catalytic gold nano-particles and subsequent plasma treatment of the sensing film. These sensors were further integrated in an inexpensive wirelessly readable RLC-circuit (where R is resistor, L is inductor and C is capacitor). The performance of these sensors towards biogenic H2S produced during the spoilage of poultry meat in the modified atmosphere package was also demonstrated in this thesis. This serves as a proof of concept that these sensors can be utilized in real life applications.

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The purpose of this thesis was to investigate environmental permits of landfills with respect to the appropriateness of risk assessments focusing on contaminant migration, structures capable to protect the environment, waste and leachate management and existing environmental impacts of landfills. According to the requirements, a risk assessment is always required to demonstrate compliance with environmental protection requirements if the environmental permit decision deviates from the set requirements. However, there is a reason to doubt that all relevant risk factors are identified in current risk assessment practices in order to protect people end environment. In this dissertation, risk factors were recognized in 12 randomly selected landfills. Based on this analysis, a structural risk assessment method was created. The method was verified with two case examples. Several development needs were found in the risk assessments of the environmental permit decisions. The risk analysis equations used in the decisions did not adequately take into account all the determining factors like waste prospects, total risk quantification or human delineated factors. Instead of focusing on crucial factors, the landfill environmental protection capability is simply expressed via technical factors like hydraulic conductivity. In this thesis, it could be shown, that using adequate risk assessment approaches the most essential environmental impacts can be taken into account by consideration of contaminant transport mechanisms, leachate effects, and artificial landfill structures. The developed structural risk analysing (SRA) method shows, that landfills structures could be designed in a more cost-efficient way taking advantage of recycled or by-products. Additionally, the research results demonstrate that the environmental protection requirements of landfills should be updated to correspond to the capability to protect the environment instead of the current simplified requirements related to advective transport only.

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The increasing presence of products derived from genetically modified (GM) plants in human and animal diets has led to the development of detection methods to distinguish biotechnology-derived foods from conventional ones. The conventional and real-time PCR have been used, respectively, to detect and quantify GM residues in highly processed foods. DNA extraction is a critical step during the analysis process. Some factors such as DNA degradation, matrix effects, and the presence of PCR inhibitors imply that a detection or quantification limit, established for a given method, is restricted to a matrix used during validation and cannot be projected to any other matrix outside the scope of the method. In Brazil, sausage samples were the main class of processed products in which Roundup Ready® (RR) soybean residues were detected. Thus, the validation of methodologies for the detection and quantification of those residues is absolutely necessary. Sausage samples were submitted to two different methods of DNA extraction: modified Wizard and the CTAB method. The yield and quality were compared for both methods. DNA samples were analyzed by conventional and real-time PCR for the detection and quantification of Roundup Ready® soybean in the samples. At least 200 ng of total sausage DNA was necessary for a reliable quantification. Reactions containing DNA amounts below this value led to large variations on the expected GM percentage value. In conventional PCR, the detection limit varied from 1.0 to 500 ng, depending on the GM soybean content in the sample. The precision, performance, and linearity were relatively high indicating that the method used for analysis was satisfactory.

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A method for determination of organohalogen pesticides in strawberry by gas chromatography with electron capture detection was validated and applied in a monitoring program. Linearity, matrix effects, and day effect were evaluated for the analytes alpha-endosulfan, beta-endosulfan, endosulfan sulphate, lambda-cyhalothrin, procymidone, and trifluralin. The linear range varied according to the chromatographic response of the analyte. Significant matrix effects were observed. The mean recoveries ranged from 74.6 to 115.4%, with repeatability standard deviations between 1.6 and 21.0% and intermediate precision between 5.9 and 21.0%. Detection, quantification and decision limit, and detection capacity ranged from 0.003 to 0.007 mg/kg, 0.005 to 0.013 mg/kg; 0.003 to 3.128 mg/kg; and 0.005 to 3.266 mg/kg, respectively. The method was fit for the purpose of monitoring organohalogen residues in strawberries. Residues of these pesticides were detected in 124 of the 186 samples analyzed between 2009 and 2011 in the state of Minas Gerais. Nine of them did not comply with the current legislation requirements; among them, seven (3.8%) had residues of unauthorized pesticide for the culture of strawberry, one (0.5%) had residues above the maximum residue limit, and another one (0.5%) exhibited both non-conformities.

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CSR has been subject of broad debate and research over the decades and has gained attention recently. The purpose of this thesis is to find out how companies perceive CSR. In addition this thesis is researching what is CSR in Finnish companies, how do companies measure CSR, what are the effects of CSR and how companies perceive those effects and what actors and factors support CSR. This research is a case study where altogether nine informants from seven companies were interviewed. This research is qualitative case study implemented with theme interviews. The analysis method is content analysis. Several interesting issues emerged from the empirical findings. CSR is playing pivotal role in companies values, vision and mission. CSR was perceived differently in companies but also mutual points emerged. The role of stakeholders is essential in CSR. In addition the communication with stakeholders was seen very important. Companies perceived that they can gain many benefits when acting responsibly for instance in issues related to cost reduction, reputation and personnel. However measuring these effects from CSR point of view was seen challenging. Other CSR related challenges are for example change and lack of resources. When considering empirical findings from a theoretical point of view, three interesting issues emerged. CSR reports play an important role in measuring and developing of CSR. However, this is not the case with all companies and some of them argued that reporting has too much attention nowadays when talking about CSR. The benefits of CSR are mostly related to responsive CSR. However maybe in a long-term follow-up strategic CSR related competitive advantage benefits could be more easily noticed. Many different issues supported CSR. Some issues are driven by outside of companies like NGO`s and media and some inside like the motivation of personnel and management. Vastuullista liiketoimintaa on tutkittu vuosien saatossa laajalti ja se on saanut viime vuosina erityisen paljon huomiota. Tämän pro gradu –tutkielman tavoitteena on selvittää, miten yritykset kokevat vastuullisen liiketoiminnan. Tämän lisäksi tutkimuksessa selvitetään, mitä vastuullinen liiketoiminta suomalaisissa yrityksissä tarkoittaa, miten yritykset mittaavat omaa vastuullisuuttaan, mitkä ovat vastuullisuuden vaikutukset, miten yritykset kokevat vastuullisuuden vaikutukset ja mitkä tekijät tukevat vastuullisen liiketoiminnan syntyä. Tutkimus toteutettiin haastattelemalla yhdeksää suomalaisen yrityksen yritysvastuusta vastaavaa tai sen kanssa työskentelevää henkilöä seitsemästä eri organisaatiosta loppuvuodesta 2014 ja alkuvuodesta 2015. Tutkimus on laadullinen, teemahaastatteluilla toteutettu haastattelututkimus. Aineisto on analysoitu teemoittain. Tutkimusaineiston perusteella vaikuttaa siltä, että vastuullinen liiketoiminta on tärkeässä roolissa yritysten arvoissa, visiossa ja missiossa. Yritysvastuu koettiin yrityksissä erilailla, mutta myös yhtäläisyyksiä on nähtävissä. Sidosryhmien rooli on erittäin tärkeä yritysvastuusta puhuttaessa ja myös kommunikointi sidosryhmien kanssa nousi tärkeäksi aiheeksi. Yritykset kokivat saavuttavansa monia hyötyjä vastuullisesta toiminnasta kuten kustannussäästöihin, maineeseen ja työntekijöihin liittyvissä asioissa. Näiden hyötyjen mittaaminen yritysvastuun näkökulmasta koettiin kuitenkin haasteelliseksi. Muita vastuullisuuteen liittyviä haasteita olivat esimerkiksi siihen liittyvä muutos sekä niukat resurssit. Tutkimuksen johtopäätöksistä nousi esille kolme merkittävää seikkaa. Vastuullisuusraportoinnin koettiin olevan hyödyllinen yritysvastuun mittaamisessa ja kehittämisessä. Kaikki yritykset eivät kuitenkaan olleet tätä mieltä ja osa koki raportoinnin saavan liian paljon huomiota nykypäivänä. Yritysten kokemat hyödyt vastuullisuuteen liittyen syntyivät pääosin reaktiivisesta vastuullisuudesta. Tässä kohdin on kuitenkin huomionarvoista mainita, että strategisen vastuullisuuden hyödyt olisivat saattaneet nousta paremmin esille pidemmän aikavälin tutkimuksessa. Yritysvastuun syntyä tukevia tekijöitä löytyi monia. Osa tekijöistä oli yrityksen ulkopuolisia kuten kansalaisjärjestöt ja media ja jotkut taas kumpusivat yrityksen sisältä esimerkiksi työntekijöiden ja johdon motivaatio.

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The aim of this Master’s Thesis was to examine whether corporate social responsibility and CSR communication has effect on company’s image in the eyes of 18-25 year olds young job seekers and thus study young adults perceptions on these issues. By utilizing previous academic literature a through picture of the main topics was built and by conducting quantitative research, research’s aim was sought to answer. The framework defines the link between research’s main concepts corporate image, CSR and CSR communication and how this can lead to attracting prospective employees. A quantitative research method was applied and an online survey was sent to people whom had applied for L&T by June during the year 2015. Out of these people, those who were aged 18-15 and had vocational education were qualified to answer the survey. The data was analyzed by utilizing statistical analysis and causal relationships were found though which the explanation of perceptions and impacts was possible. The results showed that young adults are influenced by CSR and CSR communication and thus these factors have an impact on prospective employees.

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The aim of this thesis is to find and analyze different methods which reduce fluid bed boilers’ auxiliary power consumption. The objective is to examine the effects and feasibility of these methods. The literature part explains how fluid bed boilers work and what are the main sources of auxiliary power consumption. Designs and operation of these equipment are presented. The literature part also discusses the basics of auxiliary power consumption reduction and introduces four low pressure drop constructions. The experimental part inspects six different methods. Effects of these methods on the auxiliary power consumption are calculated and their impacts on the operation of the boiler are modeled. Calculations show that reasonable changes can reduce fluid bed boiler’s auxiliary power consumption by 2,1-10,2 %. Biggest reductions come from lower air coefficients, smaller bed a-level pressures and lower primary/secondary air –ratios. Models showed no problems with the smaller bed a-level pressures. With the lower air coefficients and smaller primary/secondary air –ratios the models showed a significant increase in the carbon monoxide levels.

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Beliefs about the rightness or wrongness of engaging in various antisocial acts, referred to here as nonnative beliefs legitimizing antisocial behaviour (nblab), have been shown to playa role in the emergence oflater antisocial behaviour. The current study represented an attempt to understand whether parental monitoring and parent-child attachment have differential relationships with these antisocial nonnative beliefs in adolescents of different temperaments. The participants, 7135 adolescents in 25 high schools (ages 10- 18 years, M = 15.7) completed a wide-ranging questionnaire as part of the broad Youth Lifestyle Choices - Community University Research Alliance project, whose goal is to identify and describe the major developmental pathways of risk behaviours and resilience in youth. Two aspects of monitoring (monitoring knowledge and surveillance/tracking), attachment security, and two measures of temperament (activity level and approach) were examined for main effects and in interactions as predictors of adolescent nonnative beliefs. All of these measures were based on adolescent self-ratings on either 3- or 4-point Likert-type scales. Several important results emerged from the study. Males were higher than females in nblab; parental monitoring knowledge and adolescent attachment security were negatively related to nblab; and temperamental activity level was positively related. Monitoring knowledge, the strongest of the predictors, was much more strongly related to nonnative beliefs than was parental surveillance/tracking, supporting the contention that it is how much parents actually know, and not their surveillance efforts, that predict adolescent nonnative beliefs. A surprising finding that is of the utmost importance was that, although several of the interactions tested were significant, none were considered to be of a meaningful magnitude (defined as sr^ > .01). The current study supported the suggestion that normative beliefs legitimizing antisocial behaviour are multiply determined, and the results were discussed with respect to the observed differential relations of parental monitoring, parent-child attachment, temperament, age, and gender to antisocial normative beliefs in adolescents. Also discussed were the need to test other parenting, temperament, and other variables that may be involved in the development of nblab; the need to directly test possible mechanisms explaining the links among the variables; and the usefulness of longitudinal research in determining possible directions of causality and developmental changes in the relationships.

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This study examined students considered at risk of non-completion of their Ontario Secondary School Diploma and aimed to offer insight into the questions, "What factors currently lead to school disconnect" and "How can these factors be addressed?" Eight students currently enrolled in an alternative learning environment participated in the study. Each was asked to take part in two, digitally recorded interviews that were subsequently transcribed by the researcher. The data were then coded and analysed according to specific themes: obstacles, empowerment, goals, views about success, opinions of school, and power of the teacher. From these themes, three broad focus areas emerged that were used to keep the data analysis focused: worldview, school effects, and self-image. Variances between the data collected and ideas presented in the current literature were highlighted as a reminder that when dealing with a human population, we cannot rely on textbook definitions and theory alone.

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Educators should movefrom teacher-centered learning to student-centered learning, from isolated work to collaborative work, andfromfactual knowledgebased instructions to critical thinking and informed decision-making. The high tech classroom should be more interactive and encourage active, exploratory, inquiry-based learning, as opposed to the didactic mode in which teachersfeed students information. (Valenti,2000, p. 85) The influence of technology in schools is growing as quickly as the students it impacts. As a pioneer in an e-leaming high school, I hoped to better understand the effects and influences of this learning tool in the English classroom. Using interpretive ethnography as my main frame of reference, I examined the role of technology in a grade 9 Academic English class environment. My role was participant observer as I worked with 4 students in the Laptop Program at St. Augustine Catholic High School. Through interview, observation, joumaling, and thick description, I undertook a journey into cyberspace. I documented the experiences, the frustrations, and the highlights of being in e-leaming along with my students. In this study, I specifically considered the issues of teacher training, administrative support, technology support personnel, resource availability, the role of the teacher in a constructivist classroom, and the benefits of the laptop computer as a learning tool in classroom and school.

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Cytokines have been shown to cause a reduction in nerve conduction when examined using animal models. Such effects, if shown in humans, could result in detrimental effects to physical function during periods heightened systemic cytokine concentrations. The study investigated the acute effects of cytokines on nerve conduction velocity (NCV) and functional measures. Measures were taken under both basal and elevated cytokine concentrations to determine any corresponding changes to NCV. A significant positive correlation was found between the cytokine IL-6 and NCV at 2 hours post-exercise (r=0.606, p=0.048). A significant negative correlation was found between IL-1ra and NCV at 24 hours post-exercise (r=-0.652, p=0.021). A significant positive correlation was also found between IL-1ra and endurance at 1 hour post-exercise (r=0.643, p=0.033). As such, it would seem that IL-6 may potentially act to enhance nerve function while other cytokines such as IL-1ra may have negative effects and reduce NCV.