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Water is absolutely essential for the normal functioning of the skin and especially the stratum corneum (SC). However, as the SC is continuously exposed to varying humidities, maintenance of water within the tissue is crucial. Under most circumstances water present within the SC will be derived from bodily water, being lost by transepidermal water loss, and is normally bound by proteins together with naturally occurring hygroscopic compounds found largely within, but also external to, the corneocytes. Small amounts of water escape through this slightly leaky barrier to hydrate the dehydrated outer layers of the SC, and this is key to maintaining SC flexibility, SC maturation and SC desquamation. The retention of water in the SC is dependent on three major mechanisms: (a) the intercellular lamellar lipids whose physical conformation, predominantly an orthorhombic gel phase, provides a tight and effective barrier to the passage of water through the tissue, (b) the presence of corneodesmosome-bound and ceramide-hydrophobed corneocytes which influence the tortuosity of the SC and thereby the diffusion path length of water and (c) the presence of both intracellular and extracellular SC natural moisturizing factors (NMF). The structure, biochemistry and function of the SC and the epidermis can however be disturbed upon environmental challenge, particularly by disruption of the SC barrier resulting in the precipitation of dry flaky skin conditions. The maintenance of barrier function and thereby SC hydration is central to the production and optimal functioning of the SC. Fluctuating atmospheric conditions (high and low dew points) influence the formation of the epidermal barrier lipids, NMF, corneocyte envelope phenotypes and the desquamatory enzymes and are thus an initiator of dry skin. At low atmospheric dew points, the reduced SC water content precipitates the dry skin phenotype. On perturbation of barrier function, a cycle of events begins initially with the superficial dehydration of the SC (leaking of extracellular lipids, disruption of lipid lamellar architecture, loss of water-soluble NMF), the release of inflammatory mediators, induction of hyperproliferation of epidermal keratinocytes resulting in disturbed epidermal differentiation leading to an inferior SC (enhanced production of sphingosine-containing ceramides relative to phytosphingosine-containing ceramides and reduced transglutaminase activity leading to retention of fragile corneocyte envelopes in the superficial layers of the SC that have reduced levels of covalently bound ceramides), together with a flaky skin condition (reduced desquamatory enzyme activities and reduced corneodesmolysis). In extreme cases when inflammation is present, increased levels of proteases are observed in the SC and reduced interleukin 1 (IL-1) levels with increased IL-1 receptor antagonist protein levels. If left untreated, these events will continuously cycle to produce an even poorer skin condition, and ultimately mechanical cracking of corneodesmosomes between the corneocytes will result in mechanical trauma to the SC.

Load problems in electricity markets occur both on the supply and demand side and can have technical, economic and even political causes. Commonly, such problems have been solved by expanding production and/or distribution capacity, importing electricity or by load management. Load management is a techno-economic measure for harmonizing the relations between supply and demand sides, optimizing power generation and transmission and increasing security of supply. Interest in load management differs depending on the perspective of the actors involved: from customer, utility, or producer to state policymaker. The problem of load demand and load management in residential sector is in this thesis approached from different perspectives, i.e. technical, economic, and environmental. The study does not go deep into detailed analyses of each perspective, but rather aims to establish and analyze the links between them. This trans-disciplinary approach is the key methodological moment used in the research work performed by the research group for load management in buildings at the Lund Institute of Technology. The key objective of this study is to analyze load demand variation and load management possibilities in residential sector, particularly detached and semi-detached houses, to experimentally test and analyze the conditions and potential of direct load management from customer and utility viewpoint. Techno-economic and environmental aspects are investigated. The study was performed in collaboration with one electric utility in Southern Sweden. Ten electric-heated houses were equipped with extra meters, enabling hourly load measurements for heating, hot water and total electricity use. Household heating and hot water systems were controlled by the utility using an existing remote reading and monitoring system. The residents noticed some of the control periods, although they didn't express any larger discomfort. The experiments proved that direct load management might be a possible solution for the utility to solve their peak demand problems. Another solution, considered by the utility and analyzed in this study is a construction of diesel peak power plant. This alternative has negative environmental consequences compared to load management. The analysis of environmental aspects was extended to national level. To include an environmental perspective is a novel approach, since traditionally, load management evaluation is limited the economic and technical viewpoints. It identifies and discusses the possible environmental benefits of load management and evaluates their significance, primary focusing on CO2 emissions reduction. The results show the importance of considering the influence of site-specific or level-specific conditions on the environmental effects of load management. On the national level, load management measures can hardly provide significant environmental benefits, since hydropower is used as the demand following production source in Sweden. Emission reductions will rather be the result of energy efficiency measures, which will cut the load demand as well as the energy demand.

PurposeThis study of environment management systems implementation in Swedish universities contributes to the dialogue about the role of management systems as tools in developing sustainability in higher education.Design/methodology/approachThe empirical study is based on Government directives that make environmental management systems implementation compulsory for all public organisations in Sweden, annual environmental reports of Swedish universities for the years 1997‐2002, their internet home pages, and a survey.FindingsMany universities focus only on direct environmental aspects like paper use and waste handling, even though the main tasks of the universities, namely education, research and co‐operation with the surrounding society, that is the indirect aspects, are likely to have a considerable environmental impact. The organisation of the environmental work and the placement of the environmental coordinator also vary. Two main patterns appear; the coordinator has a function in the service department or an administrative function in the president's office. The goal of certification increases the likelihood of the environmental coordinator being placed in the president's office.Originality/valueThe aim is to increase the understanding of why and how a concept that was first introduced in industry is applied to institutions of higher education.

Metadata only record ; Coastal erosion is one of the major coastal problems currently facing Tanzania. Several factors, including sea level rise, geology, and rapid coastal population growth accompanied by rapid increase of human activities that interfere with natural processes, have been linked to the problem. One of the human activities that has been well linked to the problem of coastal erosion is illegal sand mining along beaches, coastal streams/rivers, and other restricted areas. This causes localized accelerated/severe coastal erosion and enormous environmental degradation and threat to coastal properties. Illegal sand mining is presently a big industry in Tanzania, employing many youths, and has become a social, economic, and environmental problem. The problem of illegal sand mining in Tanzania is revisited, and possible measures to control it are proposed. Measures that can help to reduce/eliminate illegal sand mining are: governments to address effectively the problem of unemployment and poverty in the society by formulation of effective policies, including the total liberalization of the labour market and reduction of the tax burden and regulations on potential employers; identifying alternative sources of sand that are environmentally safe to mine, of good quality, and easily accessible; launching well-focused mass education on the problem of coastal erosion; encouraging formation of legally registered associations of sand-miners that will work closely with relevant authorities to curb illegal sand mining; and strengthening of governance and improving research funding in the country.