120 research outputs found
Energy and Economic Performance of Solar Cooling Systems World Wide
AbstractSolar thermal cooling systems have been installed as pilot projects in most regions of the world, but due to the low number of total installations there is not yet much experience available about system sizing and design. To counter the lack of experience and to evaluate the potential of energy efficient solar cooling systems, a systematic system design study has been carried out covering most climatic regions worldwide. For each technology investigated, an energy optimized control strategy was developed which maximizes the primary energy efficiency. This control strategy was implemented in the simulation environment INSEL and system models were developed for a range of thermal cooling technologies and validated with operating experiences from different plants monitored by the authors.It could be shown that a reduction of nominal chiller power by 30% to 40% or more hardly effects the solar cooling fraction for most climates, but significantly increases the machine operating hours and thus improves the economics. The lower the nominal power of the chiller, the higher the recommended ratio of collector surface area per kW. For a given machine nominal power, solar cooling fractions increase with collector surface area until saturation is reached. Collector surface areas can be as high as 5 m2 to 10 m2 per kW with still increasing solar cooling fractions, but acceptable specific collector yield reduction. The economic optimum is reached for less solar cooling fraction and thus lower primary energy savings. Single effect absorption cooling systems easily reach 80% solar cooling fraction for all but very humid climates. Primary energy ratios can be over 3.0, depending on system design and cooling load data. CO2 and primary energy savings of 30 – 79% are achievable.The economic study showed that solar thermal cooling is more viable in hot climates than in moderate European climates. Annual costs strongly depend on the locations. The specific costs per kWh cooling in German locations vary between 0.25 and 1.01 €/kWh, in Spanish locations between 0.13 and 0.30 €/kWh. In hot climates like Jakarta and Riyadh the specific costs are as low as 0.09 to 0.15 €/kWh. Furthermore the maximum investment costs were calculated get a payback time of 10 years
Zusammenleben der Generationen und Perspektiven der Generationenarbeit
Der vorliegende Beitrag beschreibt die Generationenbeziehungen in ihrem Ausmaß, in ihren unterstützenden Funktionen und mit ihren Konflikten. Darüber hinaus zeigt er, welche Möglichkeiten der außerfamiliären Generationenbeziehungen es gibt und wie sich das Miteinander der Generationen fördern lässt. Der Beitrag ist im Einzelnen folgendermaßen gegliedert: Im ersten Kapitel wird die demographische Entwicklung beschrieben. Das zweite Kapitel erklärt den Unterschied zwischen dem Verhältnis und der Beziehung zwischen den Generationen. Es fragt weiter, ob aus den neuartigen Altersstrukturen mit einem deutlich gewachsenen Anteil der Älteren an der Bevölkerung Konflikte entstehen auf der Ebene des politischen Einflusses, der sozialstaatlichen Mittelverteilung und bezüglich der Einstellungen und Wertmuster. Das dritte Kapitel beschreibt Haushaltsformen und Familienstand als Merkmale der Lebenssituation Älterer. Da die meisten älteren Menschen alleine leben, richtet sich das Interesse auf die Beziehungen, die zwischen den eigenständigen Haushalten der Generationen im Familienverband bestehen (Kapitel vier). Intergenerationelle Hilfe und Unterstützung werden in Kapitel fünf skizziert und die mittlere sowie die ältere Generation werden als Geber und Empfänger in diesem Beziehungsnetz verortet. Insbesondere wird die Rolle des familiären Netzes bei der Versorgung hilfe- und pflegebedürftiger älterer Menschen beleuchtet. (ICD)"Usually the public media depict intergenerational relationships as loosely bound and distant. In this view elderly people would live single and separated from their offspring, weak family ties in general would manifest themselves in a weak relationship to the elderly parents and little exchange of help and mutual support. This widespread public image is corrected by the report. In a first step the demographic development is outlined and the thesis about a coming 'war between the generations' is discussed. In a second step information about the living conditions of the elderly in different households which are important preconditions for intergenerational relationships are given. In the third part the report deals with intergenerational relationships with reference to historical new development towards overlapping lifecycles in this century. Regarding geographical distance and contacts, in the average population we cannot speak about deficits. The majority lives together closely. Although it is not common among elderly parents to share a household with adult children, they have regular contact. But there is a minority living in a greater distance and with rare contacts. Emotional relationships are close, especially between daughter and mother. Again, certain groups will not show this pattern. The mentioned closeness does not prevent conflicts. Social support follows a specific pattern. The generation in the middle has more exchange with own offspring and vice versa. Concerning the need for support in the older population, a spouse or a partner is of primary importance in most areas. But elderly who are widowed or living without a partner will refer to their children as the primary helpers. Most of social support is given within the family, especially by the middle generation. The report outlines the necessity for professional care services as well as the use of the German care insurance. An elaborated system of social support and medical care for elderly people exists. But regarding the impact of demographic changes, this system in its current shape is hardly capable of replacing family ties. Thus the necessity to develop intergenerational contacts and mutual help outside the family is outlined in chapter six. In a 'greying society' we need to support the contacts between generations beyond the boundaries of families. Therefore in the last chapter, the report deals with approaches to intergenerational work that aim at supporting the dialog between generations. Models in Bavaria are presented to generate the motivation for a further growth of intergenerational work." (author's abstract
Introduction
Species categories are not simply an invention of the human mind. Plants, animals, fungi, and viruses engage in species making by mingling and separating.1 Yet, at the same time, the boundaries that define or differentiate species are not simply natural ; they are actively made, maintained, politically charged, and fashioned to serve some needs more than others, inviting new essentialisms even as they alert us to important differences. Like other rubrics for organizing social worlds—race, ethnicity, gender, age, ability—the concept of species and the alternative classifications it invites are complicated and controversial. Whether wild or domestic, pet or pest, such categories are subject to temporally fluctuating human motives, shifting values, and cultural diversities
Introduction
Species categories are not simply an invention of the human mind. Plants, animals, fungi, and viruses engage in species making by mingling and separating.1 Yet, at the same time, the boundaries that define or differentiate species are not simply natural ; they are actively made, maintained, politically charged, and fashioned to serve some needs more than others, inviting new essentialisms even as they alert us to important differences. Like other rubrics for organizing social worlds—race, ethnicity, gender, age, ability—the concept of species and the alternative classifications it invites are complicated and controversial. Whether wild or domestic, pet or pest, such categories are subject to temporally fluctuating human motives, shifting values, and cultural diversities
Thiol-Based Redox Switches in Eukaryotic Proteins
Abstract For many years, oxidative thiol modifications in cytosolic proteins were largely disregarded as in vitro artifacts, and considered unlikely to play significant roles within the reducing environment of the cell. Recent developments in in vivo thiol trapping technology combined with mass spectrometric analysis have now provided convincing evidence that thiol-based redox switches are used as molecular tools in many proteins to regulate their activity in response to reactive oxygen and nitrogen species. Reversible oxidative thiol modifications have been found to modulate the function of proteins involved in many different pathways, starting from gene transcription, translation and protein folding, to metabolism, signal transduction, and ultimately apoptosis. This review will focus on three well-characterized eukaryotic proteins that use thiol-based redox switches to influence gene transcription, metabolism, and signal transduction. The transcription factor Yap1p is a good illustration of how oxidative modifications affect the function of a protein without changing its activity. We use glyeraldehyde-3-phosphate dehydrogenase to demonstrate how thiol modification of an active site cysteine re-routes metabolic pathways and converts a metabolic enzyme into a pro-apoptotic factor. Finally, we introduce the redox-sensitive protein tyrosine phosphatase PTP1B to illustrate that reversibility is one of the fundamental aspects of redox-regulation. Antioxid. Redox Signal. 11, 997-1014.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/78110/1/ars.2008.2285.pd
Directed evolution of the suicide protein O⁶-alkylguanine-DNA alkyltransferase for increased reactivity results in an alkylated protein with exceptional stability
Here we present a biophysical, structural, and computational analysis of the directed evolution of the human DNA repair protein O-6-alkylguanine-DNA alkyltransferase (hAGT) into SNAP-tag, a self-labeling protein tag. Evolution of hAGT led not only to increased protein activity but also to that the reactivity of the suicide enzyme can be influenced by higher stability, especially of the alkylated protein, suggesting stabilizing the product of the irreversible reaction. Whereas wild-type hAGT is rapidly degraded in cells after alkyl transfer, the high stability of benzylated SNAP-tag prevents proteolytic degradation. Our data indicate that the intrinstic stability of a key a helix is an important factor in triggering the unfolding and degradation of wild-type hAGT upon alkyl transfer, providing new insights into the structure-function relationship of the DNA repair protein
Strategies for copper reduction in grapevine, apple, roses and vegetables by using alternative experimental products
Reducing the use of copper fungicides with the aim of phasing out has a high priority in European policy as well as in organic farming. To reach this goal without compromising yields, all preventive strategies have to be implemented and several affordable alternative products need to be brought to the market. Within the EU-funded project RELACS (2018-2022), we investigated alternative compounds that had reached a high technology readiness level. We focused on major copper-relevant crops/pathogens (grapevine/Plasmopara viticola, apple/Venturia inaequalis, vegetables/downy mildews/late blight, oil-producing roses). As alternatives, two plant extracts including licorice leaf extract (Glycyrrhiza glabra) and a larch bark extract (Larix decidua), a rare sugar (tagatose) as well as a test product based on fatty acids (NEU 1143F in apple) were evaluated. Refined strategies with these alternatives were tested, adapted and validated under practical conditions in different European countries, and further aspects of importance (e.g. mode of action, wine fermentation, compatibility with other plant protection products) examined. All alternatives proved to be effective in one or more of the investigated crops. In some cases, their efficacy as stand-alone treatment was comparable to that of copper. In other cases, the combination of the alternatives with reduced amounts of copper or in combination with other standard methods provided effective protection of the crops
Umsetzung der Energiestrategie 2050 - Band II : Neue Ansätze für Staat und Wirtschaft
In diesem, dem zweiten Band von "Energy Governance" befassen sich die Autoren aus vielfältiger Perspektive mit zahlreichen Fragen zur Umsetzung der Energiestrategie 2050. Sie identifizieren jene Fälle von Solaranlagen, bei denen der Ersatz einer Baubewilligung zu Rechtsunsicherheit führt. Sie untersuchen die Wirkung moderner Finanzberichterstattung auf die Politik der kantonalen Beteiligungen an Energieversorgungsunternehmen in einer Marktumgebung tiefer Strompreis. Analysiert wird weiter die staatliche Förderung der erneuerbaren Stromproduktion im Hinblick auf ihre Wirkung. Eine kritische Analyse der "Smart City"-Projekte in der Schweiz und in den Nachbarländern Deutschland und Österreich führt zu Empfehlungen, wie solche Projekte effizienter geplant und umgesetzt werden können. Auch die Beziehung öffentlicher Organisationen zu ihrer "Stakeholder-Umwelt" wird behandelt
Umsetzung der Energiestrategie 2050: Herausforderungen und Chancen für Staat und Wirtschaft
Sammelband der Reihe "Energy Governance Working Paper" Nr. 1 bis 7Die Energiestrategie 2050 des Bundes definiert anspruchsvolle Ziele. Für deren Erreichung hat der Bundesrat daher unter anderem den Aktionsplan Energieforschung ins Leben gerufen. Dazu wurden acht sogenannte SCCERs, Swiss Competence Center for Energy Research, initiiert, in denen hochschulübergreifend angewandte Energie-Forschung betrieben wird. Die Zürcher Hochschule für Angewandte Wissenschaften (ZHAW) ist an vier dieser acht SCCERs aktiv beteiligt.
Die ZHAW hat diese Aufgabe zum Anlass genommen, Energieforschung zum strategischen Schwerpunkt der gesamten Fachhochschule zu erklären und in allen Departementen Kompetenzaufbauprojekte zu starten. Der vorliegende Sammelband präsentiert die ersten Ergebnisse dieser Kompetenzaufbauprojekte an der School of Management and Law, wobei zwei dieser Projekte in Zusammenarbeit mit Forschern aus den Departementen Angewandte Linguistik und School of Engineering erfolgten. Dabei wurden die Herausforderungen und Chancen, die sich für Staat und Wirtschaft aus der Umsetzung der Energiestrategie 2050 ableiten, auf verschiedenen Ebenen betrachtet: die Schweiz im internationalen Vergleich, Besonderheiten der Führung von EVUs, rechtliche und ökonomische Rahmenbedingungen und die Gestaltung der Energie-Zukunft in Schweizer Städten
The Swiss Approach - feasibility of a national low-dose CT lung cancer screening program
BACKGROUND
Lung cancer is the leading cause of cancer-related deaths in Switzerland. Despite this, there is no lung cancer screening program in the country. In the United States, low-dose computed tomography (LDCT) lung cancer screening is partially established and endorsed by guidelines. Moreover, evidence is growing that screening reduces lung cancer-related mortality and this was recently shown in a large European randomized controlled trial. Implementation of a lung cancer screening program, however, is challenging and depends on many country-specific factors. The goal of this article is to outline a potential Swiss lung cancer screening program.
FRAMEWORK
An exhaustive literature review on international screening models as well as interviews and site visits with international experts were initiated. Furthermore, workshops and interviews with national experts and stakeholders were conducted to share experiences and to establish the basis for a national Swiss lung cancer screening program.
SCREENING APPROACH
General practitioners, pulmonologists and the media should be part of the recruitment process. Decentralisation of the screening might lead to a higher adherence rate. To reduce stigmatisation, the screening should be integrated in a "lung health check". Standardisation and a common quality level are mandatory. The PLCOm2012 risk calculation model with a threshold of 1.5% risk for developing cancer in the next six years should be used in addition to established inclusion criteria. Biennial screening is preferred. LUNG RADS and NELSON+ are applied as classification models for lung nodules.
CONCLUSION
Based on data from recent studies, literature research, a health technology assessment, the information gained from this project and a pilot study the Swiss Interest Group for lung cancer screening (CH-LSIG) recommends the timely introduction of a systematic lung cancer screening program in Switzerland. The final decision is for the Swiss Cancer Screening Committee to make
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