784 research outputs found
Poti v Dübnovo zbirko: kako sta Gustav Düben in njegov sin pridobivala muzikalije
The article describes the practices of acquisition of music behind the üben Collection. Music was copied into manuscripts from prints, but was also obtained in the form of groups of manuscripts from different regions of Europe. Close personal contacts and networks seem to have been more important than traditional trade routes.Razprava opisuje, na kakšne načine so prihajale muzikalije v Dübnovo zbirko. Glasbo so zanjo prepisovali iz tiskov, so pa tudi iz raznih predelov Evrope pridobivali cele skupine rokopisnih prepisov. Z di se,da so bila tesna osebna prijateljstva in zasebne mreže pri tem pomembnejše kot uradne tržne poti
Cellulose nanofibers networks for structural nanomaterials and biocomposites with multiple functions
Cellulose-based composites offer interesting potential as environmentally friendly materials. Wood nanocellulose disintegrated from chemical pulp is an interesting component, which can be used in materials of increased structural, sophistication, extended property range and new functions [1]. The network forming character of cellulose nanofibers (CNF) makes it possible to form other types of nanomaterials than biocomposites such as nanopaper, aerogels, hydrogels, foams and honeycombs. The CNF can also be combined with inorganic nanoparticles to prepare organic/inorganic hybrid materials.
The structure of CNF is discussed and routes to improve the properties of the CNF are suggested. For the purpose of nanomaterials preparation, structural control is essential. The processing of colloidal suspensions offers many advantages in terms of controlled particle dispersion, possibilities for orientation and the combination of multiple functionalization strategies. The core-shell nanofiber approach is particularly interesting [2]. It allows the possibility to tailor the distribution of the polymer matrix, and also to improve the moisture stability of the nanocomposite system. Both interface and interphase regions can be better controlled by this approach.
Thermoset biocomposites have also been studied, and CNF combined with epoxy (EP) is particularly promising [3]. The epoxide can react with surface hydroxyls on CNF so that covalent polymer matrix-nanofiber interactions results. This interface is characterized by excellent hygromechanical stability. The CNF/EP composites are also very ductile, due to the characteristics of the CNF network.
CNF can also have specific and favorable interactions with unmodified carbon nanotubes (CNT). The stability of the suspension is improved so that no surface modification is required for the CNT. The suspension can be filtered so that a nanofiber paper or nanocomposite is obtained [4]. Since no surfactants are required for the CNT, the electrical conductivity of the material is exceptionally good. The mechanical properties are also favorable.
Postprandial Lipoproteins and Cardiovascular Disease Risk in Diabetes Mellitus
Diabetes mellitus is associated with increased risk for atherosclerotic cardiovascular disease (CVD). Recent prospective studies in healthy individuals suggest that the postprandial triglyceride (TG) level is a better independent predictor for assessing future CVD events than fasting TG levels. In contrast, results have been more controversial among diabetic patients, as some studies report a positive association between postprandial TG and CVD. This raises the issue of to what extent postprandial TG levels may be of predictive value in the diabetic population. One possibility impacting on the predictive power of postprandial TG in identifying CVD risk may be the presence of other risk factors, including alterations in lipid and lipoprotein metabolism, which could make it more difficult to identify the impact of postprandial lipemia on cardiovascular risk. The findings provide a challenge to develop a better approach to assess the impact of postprandial lipemia on CVD risk under diabetic conditions
Identifying Improvement Areas in Production Planning Meetings by Assessing Organisation and Information Systems at a Small Production Company
The increased mass-customisation of production requires operators to manage an increasing number of complex work tasks. From a social sustainability perspective, better sharing and dissemination of production information supports operators cognitively to manage and understand their work tasks, which in turn improves quality of work. So, the focus of this paper is to study how production planning meetings can be improved. Previous research suggests that the MEET model can be used as a framework for improving meetings and information sharing by studying 10 different areas within a company’s Organisation System (OS) and Information System (IS) whilst considering the time and place prerequisites and aims for these meetings. In this paper, the applicability of the MEET model and its 10 areas are tested at a small production company by applying two different approaches. First, a questionnaire was presented to and filled out by a manager, the results of the questionnaire identifies the improvement potential of each of the 10 areas. Second, a comprehensive current-state analysis based on observations on the shop-floor and interviews with operators were carried out with regards to the 10 areas. The results from these two approaches were compared and the comparison showed that both approaches point towards similar areas for potential improvements. This paper concludes that the MEET model can be used as a general framework to inspire change by suggesting areas with potential improvement in information sharing. While the selfassessment questionnaire can identify a direction, additional information and involvement of other stakeholders are recommended for actual implementations of change. For future research, the methods based on the MEET model will be further developed to improve accuracy and the suggestions provided to the case company in this paper will be tested as a validation of the model
Single nucleotide polymorphisms in the apolipoprotein B and low density lipoprotein receptor genes affect response to antihypertensive treatment
BACKGROUND: Dyslipidemia has been associated with hypertension. The present study explored if polymorphisms in genes encoding proteins in lipid metabolism could be used as predictors for the individual response to antihypertensive treatment. METHODS: Ten single nucleotide polymorphisms (SNP) in genes related to lipid metabolism were analysed by a microarray based minisequencing system in DNA samples from ninety-seven hypertensive subjects randomised to treatment with either 150 mg of the angiotensin II type 1 receptor blocker irbesartan or 50 mg of the β(1)-adrenergic receptor blocker atenolol for twelve weeks. RESULTS: The reduction in blood pressure was similar in both treatment groups. The SNP C711T in the apolipoprotein B gene was associated with the blood pressure response to irbesartan with an average reduction of 19 mmHg in the individuals carrying the C-allele, but not to atenolol. The C16730T polymorphism in the low density lipoprotein receptor gene predicted the change in systolic blood pressure in the atenolol group with an average reduction of 14 mmHg in the individuals carrying the C-allele. CONCLUSIONS: Polymorphisms in genes encoding proteins in the lipid metabolism are associated with the response to antihypertensive treatment in a drug specific pattern. These results highlight the potential use of pharmacogenetics as a guide for individualised antihypertensive treatment, and also the role of lipids in blood pressure control
Green and Fire Resistant Nanocellulose/Hemicellulose/Clay Foams
AbstractLightweight polymer foams from synthetic polymers are commonly used in a wide‐spread spectrum of application fields. Their intrinsic flammability coupled with restrictions on flame retardant chemicals poses a severe threat to safety. Here, fire resistant foams comprising biobased components capable of replacing petroleum‐based foams are investigated. Cellulose nanofibers are combined with 2D montmorillonite nanoplatelets and a native xyloglucan hemicellulose binder, using a water‐based freeze casting approach. Due to the silicate nanoplatelets, these lightweight foams self‐extinguish the flame during flammability tests. The limiting oxygen index is as high as 31.5% and in the same range as the best fire‐retardant synthetic foams available. In cone calorimetry, the foams display extremely low combustion rates. Smoke release is near the detection limit of the instrument. In addition, the foams are withstanding the penetration of a flame torch focused on one side of the specimen (T on surface 800 °C) and structural integrity is maintained. At the same time, the unexposed side is insulated, as demonstrated by a through‐thickness temperature drop of 680 °C cm−1. The results represent a tremendous opportunity for the development of fire‐safe foams combining excellent sustainability with multifunctional performance
Surface modification effects on nanocellulose - molecular dynamics simulations using umbrella sampling and computational alchemy
Topochemical modification of nanocellulose particles, in particular acetylation, is commonly used to reduce hygroscopicity and improve their dispersibility in non-polar polymers. Despite enormous experimental efforts on cellulose surface modification, there is currently no comprehensive model which considers both (a) the specific interactions between nanocellulose particles and the surrounding liquid or polymer matrix, and (b) the interactions between the particles themselves. The second mechanism is therefore frequently ignored. The present approach is based on atomistic molecular dynamics (MD) simulations, where computational alchemy is used to calculate the changes in interactions between nanocellulose and the surrounding medium (liquid or polymer) upon modification. This is combined with another method, based on potential of mean force, to calculate interactions between particles. Results show that both contributions are of equal importance for nanoparticle surface acetylation effects. The proposed method is not restricted to either cellulose or acetylation, and has the prospect to find application in a broad context of nanomaterials design
Insulin resistance in non-diabetic subjects is associated with increased incidence of myocardial infarction and death.
AIMS: To compare the incidence of myocardial infarction and death in non-diabetic subjects with and without insulin resistance. METHODS: Population-based prospective cohort study, in Malmö, Sweden, of 4748 non-diabetic subjects (60% women), aged 46-68 years, with no history of myocardial infarction or stroke. The prevalence of insulin resistance was established by the homeostasis model assessment (HOMA) and defined as values above the sex-specific 75th percentile (1.80 for women and 2.12 for men). Incidence of myocardial infarction and death is based on record linkage with local and national registers. Cox's proportional hazards model was used to assess the influence of insulin resistance after adjustment for age, sex, hyperglycaemia, raised arterial blood pressure, dyslipidaemia, central obesity, smoking and leisure-time physical activity. RESULTS: Sixty-two subjects suffered a coronary event, and 93 subjects died during the 6-year follow-up period. Insulin resistance was after adjustment for other factors included in the insulin resistance syndrome and other potential confounders, associated with an increased incidence of coronary events (relative risk (RR) 2.18; 95% confidence interval (CI) 1.22-3.87; P = 0.008) and deaths (RR 1.62; 1.03-2.55; P = 0.038). CONCLUSIONS: Insulin resistance, as assessed by the HOMA method, was in this cohort of middle-aged non-diabetic subjects associated with an increased incidence of myocardial infarction and death. This risk remained when smoking, low physical activity and factors included in the insulin resistance syndrome were taken into account in a stepwise regression model. Diabet. Med. 19, 470-475 (2002
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