2,945 research outputs found

    Effectiviteit van herstelbeheer in vennen en duinplassen op de middellange termijn

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    Al sinds het opstarten van de regeling OBN zijn er herstelmaatregelen uitgevoerd in vennen en duinplassen. In een deel van de wateren bleek de waterkwaliteit en de vegetatie zich goed te herstellen in de eerste vijf jaren na de ingreep, maar de Fauna bleek op korte termijn overwegend negatief te reageren. Op deze korte termijn bleek vooral herstel van abiotiek en vegetatie op te treden indien zowel vermesting als eventuele verzuring werden bestreden en hernieuwde vermesting en verzuring werden voorkomen. In de praktijk betekende dit het verwijderen van sliblagen, plaggen van oevers, verwijderen van boomopslag en voorkomen van hernieuwde vermesting door o.a. bladinwaai en te grote aantallen watervogels. Verzuring kon het beste worden voorkomen door gedoseerde inlaat van voedselarm, gebufferd water of door bekalking van het inzijggebied. Na verloop van tijd bleken er nog de nodige onbeantwoorde vragen te zijn: Hoe pakken de herstelmaatregelen op de middellange termijn uit voor de levensgemeenschappen van vennen en duinplassen? Hoe reageert de fauna op de herstelmaatregelen? Hoe reageren sier- en kiezelwieren op de herstelmaatregelen? Moet het beheer worden aangepast nu de atmosferische depositie is afgenome

    Coronary Heart Disease Risk Factors in College Students

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    More than one-half of young adults aged 18–24 y have at least 1 coronary heart disease (CHD) risk factor and nearly one-quarter have advanced atherosclerotic lesions. The extent of atherosclerosis is directly correlated with the number of risk factors. Unhealthy dietary choices made by this age group contribute to weight gain and dyslipidemia. Risk factor profiles in young adulthood strongly predict long-term CHD risk. Early detection is critical to identify individuals at risk and to promote lifestyle changes before disease progression occurs. Despite the presence of risk factors and pathological changes, risk assessment and disease prevention efforts are lacking in this age group. Most young adults are not screened and are unaware of their risk. This review provides pathological evidence along with current risk factor prevalence data to demonstrate the need for early detection. Eighty percent of heart disease is preventable through diet and lifestyle, and young adults are ideal targets for prevention efforts because they are in the process of establishing lifestyle habits, which track forward into adulthood. This review aims to establish the need for increased screening, risk assessment, education, and management in young adults. These essential screening efforts should include the assessment of all CHD risk factors and lifestyle habits (diet, exercise, and smoking), blood pressure, glucose, and body mass index in addition to the traditional lipid panel for effective long-term risk reduction

    A Nutrition Intervention to Increase Whole Grain Intake in College Students

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    This study aimed to improve whole grain (WG) intake and coronary heart disease risk factors in 98 college students through an intervention in campus dining halls. The exploratory aim was to evaluate the impact of text messaging on diet and coronary heart disease risk. The 6-week intervention consisted of WG and low-fat dairy messages in campus dining halls and text messages to a subsample (n = 26). WG intake, high-density lipoprotein cholesterol, body weight, and body mass index significantly increased over time. Total dairy intake decreased over time. Overall, the intervention had a positive impact on WG consumption and on high-density lipoprotein cholesterol

    Computer simulation of diffusion processes in tilt spatio-periodic potentials

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    Нещодавно було показано, що в істотно нерівноважних системах коефіцієнт дифузії може вести себе немонотонно з температурою. Одним із прикладів таких систем з аномальною температурної залежністю є рух броунівських часток в просторово-періодичних структурах. Метою статті було дослідження зміни температурної залежності дифузії в недодемпфованих системах з низьким коефіцієнтом тертя. В роботі методами комп'ютерного моделювання вивчено зміна коефіцієнта дифузії частинок в широкому діапазоні температур в нахилених просторово-періодичних потенціалах для різних значень коефіцієнта тертя. Показано, що дифузія досягає максимуму при певній величині зовнішньої сили. Її значення залежить від величини коефіцієнта тертя. Показано, що на відміну від звичайної залежності Аррениуса, в разі нахиленого періодичного потенціалу, максимальний коефіцієнт дифузії зростає, а не зменшується з пониженням температури експоненціальним чином. Встановлено, що така залежність характерна для всіх недодемпфованих систем. Показано, що для просторово-періодичних структур існує обмежена ділянка сил, в якому спостерігається зростання коефіцієнта дифузії зі зменшенням температури. Це область так званої температурно-аномальної дифузії (ТАД). Визначено ширина і положення області ТАД в залежності від коефіцієнта тертя γ і параметрів системи. Показано, що зі зменшенням γ, ширина області ТАД зменшується пропорційно γ. При цьому коефіцієнт дифузії в області ТАД, навпаки зростає ~γ. Отримані дані про температурно-аномальної дифузії мають важливе значення для різних областей фізики і техніки та відкривають перспективи створення новітніх технологій управління процесами дифузії.It was recently shown that in essentially nonequilibrium systems, the diffusion coefficient can behave nonmonotonically with temperature. One example of such systems with anomalous temperature dependence is the motion of Brownian particles in spatially periodic structures. The aim of the article was to study the change in the temperature dependence of diffusion in underdamped systems with a low coefficient of friction. In this paper, computer simulation methods are used to study the change in the diffusion coefficient of particles in a wide range of temperatures in oblique spatially periodic potentials for different values of the friction coefficient. It is shown that diffusion reaches a maximum at a certain external force. Its value depends on the coefficient of friction. It is shown that, in contrast to the usual Arrhenius dependence, in the case of an inclined periodic potential, the maximum diffusion coefficient increases while temperature is decreasing exponentially. It is established that such a dependence is common to all underdamped systems. It is shown that for spatially periodic structures there is a limited portion of forces in which an increase in the diffusion coefficient while decreasing temperature is observed. This is the area of the so-called temperature-anomalous diffusion (TAD). The width and position of the TAD region are determined depending on the friction coefficient γ and the system parameters. It has been shown that a decrease in γ, width TAD region decreases proportionally γ. In this case, the diffusion coefficient in the TAD region, on the contrary, increases ~γ. The data obtained on the temperature and the anomalous diffusion are important for various fields of physics and engineering, and opens new prospects for a diffusion process control technology

    Going Dutch in the Mekong Delta:a framing perspective on water policy translation

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    In response to the rising climatic impacts on worldwide urbanized deltas, the Netherlands has strategically and politically framed Dutch water management as a global water solution for improving water safety and flood protection in other countries such as Vietnam. Being renowned for its water management approach, the Netherlands is particularly active in sharing water knowledge, insights, and policies internationally. This paper connects a framing perspective to policy translation studies to understand the role of language and meaning-making in the cross-border travel of policies. Adopting a framing perspective, it presents four dimensions of water policy translation concerning how policy frames are being created and interpreted - during the cross-border travel. The paper follows the process of the Dutch water management approach being 'packaged' as global water solutions and 'translated' to inform the development of the Vietnamese Mekong Delta Plan of 2013. The results show that although similar concepts, metaphors and narratives could be witnessed in this translation process, the local use and interpretation of these concepts remain challenging. Inclusive engagement, shared and comprehensive understanding, and continuous exchange and learning processes could help to improve cross-border policy-making for sustainable delta management

    Closed-form Jones matrix of dual-polarized inverted-vee dipole antennas over lossy ground

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    This paper presents a closed-form expression for the Jones matrix of a dual-polarized inverted-vee dipole antenna based on the Lorentz reciprocity theorem and the basic rules of electromagnetic refraction. The expression is used to determine the intrinsic cross-polarization ratio (IXR) as a function of droop angle, position of the source in the sky, antenna height, frequency, and reflection coefficient of the underlying ground. The expression is verified using full-wave simulations with a method-of-moments solver, showing very good agreement. It explains the increase in the IXR when the antenna is placed over a perfect electric ground plane. This result is used to explain the polarization properties of the Square Kilometre Array Log-periodic Antenna. Through the LOw-Frequency ARray Low-Band Antenna (LOFAR-LBA), the importance of the size of the ground plane is explained. Finally, design consideration for high polarization purity antennas is discussed

    It would be a Pleasure : Augmented Reality and Engagement in a Heritage Context

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    The interchangeability, confusion and conflict of what constitutes audience engagement has a long history, with much disagreement concerning boundaries and definitions. Dewey states that it is a mistake to see the artist as active and the audience as purely passive, and argues that “the active engagement of the audience is required to fully realise any work” (Dewey 1934). This predates the notions of “interactive” or “participatory” as understood today, but highlights the longstanding appreciation of the role the audience plays in the consumption of artworks. A sentiment echoed by Duchamp (1957) stating that “the spectator adds his contribution to the creative act”. The research project presented at EVA 2017 seeks to offer a model for engagement, that of pleasure, which explores methods to motivate active participation

    Does minimally invasive lumbar disc surgery result in less muscle injury than conventional surgery? A randomized controlled trial

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    The concept of minimally invasive lumbar disc surgery comprises reduced muscle injury. The aim of this study was to evaluate creatine phosphokinase (CPK) in serum and the cross-sectional area (CSA) of the multifidus muscle on magnetic resonance imaging as indicators of muscle injury. We present the results of a double-blind randomized trial on patients with lumbar disc herniation, in which tubular discectomy and conventional microdiscectomy were compared. In 216 patients, CPK was measured before surgery and at day 1 after surgery. In 140 patients, the CSA of the multifidus muscle was measured at the affected disc level before surgery and at 1 year after surgery. The ratios (i.e. post surgery/pre surgery) of CPK and CSA were used as outcome measures. The multifidus atrophy was classified into three grades ranging from 0 (normal) to 3 (severe atrophy), and the difference between post and pre surgery was used as an outcome. Patients’ low-back pain scores on the visual analogue scale (VAS) were documented before surgery and at various moments during follow-up. Tubular discectomy compared with conventional microdiscectomy resulted in a nonsignificant difference in CPK ratio, although the CSA ratio was significantly lower in tubular discectomy. At 1 year, there was no difference in atrophy grade between both groups nor in the percentage of patients showing an increased atrophy grade (14% tubular vs. 18% conventional). The postoperative low-back pain scores on the VAS improved in both groups, although the 1-year between-group mean difference of improvement was 3.5 mm (95% CI; 1.4–5.7 mm) in favour of conventional microdiscectomy. In conclusion, tubular discectomy compared with conventional microdiscectomy did not result in reduced muscle injury. Postoperative evaluation of CPK and the multifidus muscle showed similar results in both groups, although patients who underwent tubular discectomy reported more low-back pain during the first year after surgery

    Electric Fields and Giant Vesicles

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    Background: The Internet is viewed as an important source for health information and a medium for patient empowerment. However, little is known about how seniors use the Internet in relation to other sources for health information. Objective: The aim was to determine which information resources seniors who use the Internet use and trust for health information, which sources are preferred, and which sources are used by seniors for different information needs. Methods: Questions from published surveys were selected based on their relevance to the study objectives. The Autonomy Preference Index was used to assess information needs and preferences for involvement in health decisions. Invitation to participate in this online survey was sent to the email list of a local senior organization (298 addresses) in the Netherlands. Results: There were 118 respondents with a median age of 72 years (IQR 67-78 years). Health professionals, pharmacists, and the Internet were the most commonly used and trusted sources of health information. Leaflets, television, newspapers, and health magazines were also important sources. Respondents who reported higher use of the Internet also reported higher use of other sources (P Conclusions: For these seniors who use the Internet, the Internet was a preferred source of health information. Seniors who report higher use of the Internet also report higher use of other information resources and were also the primary consumers of paper-based resources. Respondents most frequently searched for health information after an appointment rather than to prepare for an appointment. Resources used varied by health topic. Future research should seek to confirm these findings in a general elderly population, investigate how seniors seek and understand information on the Internet, and investigate how to reach seniors who prefer not to use the Internet for health information
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