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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.

Die Gefährdung der physikalischen und der sozialen Umwelt in Entwicklungsländern läßt sich mit folgenden Punkten umreißen: 1. weiterhin ansteigende Geburtenrate; 2. Verstädterungstendenzen; 3. Einsatz von Atomenergie; 4. Umweltschäden durch Chemikalien (Pestizide); 5. Umweltschäden durch Industrieabfälle und 6. Zerstörung der Wälder und Erosion der Böden. Der Autor untersucht einige Entwicklungspolitiken im Hinblick auf ihre negativen Auswirkungen auf die Umwelt mittels einer sozialen Kosten-Nutzen-Analyse und zeigt dabei auch die Möglichkeiten und die Grenzen derartiger Analysen auf. Hieran schließt eine Darstellung der Implikationen für die Entwicklungshilfepolitik an, wobei die Diskussion des Zusammenhanges zwischen Grundbedürfnissen und Umwelt im Vordergrund steht. (NG)

In the article the widespread opinion concerning the exclusively negative impact of globalization on environmental situation in developing countries is disputed. But analysis of environmental consequences of trade and investment liberalization in these states proves that the role of foreign investments in deteriorating of national environmental situation is too exaggerated. On the contrary, the "export of environmentalism" is associated with TNK activities. On the one hand, globalization originates new threats. On the other hand, the integration of developing countries into the world economy favors the solution of many environmental problems by attraction of foreign private investments in industrial development and costly infrastructure projects; transfer of clean technology; promotion of international environmental cooperation and increase of environmental responsibility of national business.

In 2021, Ukraine produced such an amount of food that it would have been possible to feed about 400 million people, not counting the population of Ukraine. The strategy for the development of the agricultural sector of Ukraine envisages providing food for 1 billion of the world's population by 2030. However, the aggression of Russia on February 24, 2022, and the subsequent hostilities led to the contamination of agricultural lands with a significant amount of Explosive Remnants of War (ERW), which requires humanitarian demining. This article is devoted to the review of the humanitarian demining process from the point of view of its impact on the environment and the determination of the main components affecting the production of agricultural products. In the first period of the demining process, there will be a significant decline in the production of agricultural products. This decline will be determined by the reduction in the area of cultivated agricultural land due to the danger of explosion. In the course of the demining and liquidation of ERW, the area of land will increase, as will the volume of production, but the quality of products will decrease due to the presence of heavy metal compounds and explosive residues in it and the deterioration of the quality of the soil itself. Therefore, after the liberation of Ukraine's territory, contaminated by mines and ERW, taking into account its importance as the world's granary, the demining time is of great importance and Ukraine will be very grateful for any help that will reduce it.