721 research outputs found
Visitors’ opinions on the environmental protection in Shumen Plateau Nature Park from the negative anthropogenic impact of a nearby city, Bulgaria
Parks are essential for the preservation and protection of wildlife, but human activity affects their functions. The objective of our study was to investigate visitors’ opinions on the environmental protection of Shumen Plateau Nature Park from the negative anthropogenic impact of a nearby city. Face-to-face interviews were conducted among summer visitors. The standardized Pearson correlation coefficient was calculated to determine the correlation between items questioned and demographic variables. The highest percentage of the informants were of the opinion that the Shumen Plateau Nature Park is a relatively clean place and a much cleaner green area compared to the parks in Shumen. According to most visitors, the high level of fine particulate matter in the air in the town of Shumen does not affect organisms that inhabit the Nature Park, soil and groundwater. The main pollutant of the Shumen Plateau Nature Park is garbage left by park visitors (88.97%), landfills in the park area (46.32%) and car traffic in the nearby town of Shumen (30.88%). The factor that has the most adverse effect on the biodiversity and ecological balance in the Nature Park are the visitors. Both visitors and inhabitants of the town of Shumen should be more responsible for the environment and the conservation of the Shumen Plateau Nature Park as a clean green area. Park visitors do not consider the town of Shumen as a source of negative anthropogenic impact on the Shumen Plateau Nature Park, but our previous studies show the opposite. This indicates a gap in the relationship between the scientific community and society that needs to be addressed. Close cooperation between scientists and journalists can contribute to the visitors’ opinions on the environmental protection in nature parks from the negative anthropogenic impact of nearby cities and towns and improve the effectiveness of the mass media
Low amounts of PEG-lipid induce cubic phase in phosphatidylethanolamine dispersions
AbstractBy using time-resolved X-ray diffraction we demonstrate that low amounts (5–10 mol%) of a phospholipid with two saturated hydrocarbon acyl chains 14 carbon atoms long and PEG550 chain covalently attached to its phosphoethanolamine polar head group, DMPE(PEG550), induce spontaneous formation of a cubic phase with lattice constant 20.5 nm (cubic aspect #8, space group Im3m) in aqueous dispersions of dielaidoylphosphatidylethanolamine (DEPE). This phase displays a highly resolved X-ray diffraction pattern with 17 low-angle reflections. The cubic phase was found to intrude in the temperature range between the lamellar liquid crystalline (Lα) phase and the inverted hexagonal phase (HII) known to form in pure DEPE/water dispersions. A higher DMPE(PEG550) amount of 20 mol% was found to eliminate the non-lamellar phases in the temperature scale up to 100°C. DMPE grafted with PEG5000 only shifts the Lα-HII transition of DEPE to higher temperatures but does not promote formation of cubic phase. These findings indicate that, consistent with their bulky head groups, the PEG-lipids decrease the tendency for negative interfacial mean curvature of the DEPE bilayers
New phases induced by sucrose in saturated phosphatidylethanolamines: an expanded lamellar gel phase and a cubic phase
AbstractA new lamellar gel phase (Lβ) with expanded lamellar period was found at low temperatures in dihexadecylphosphatidylethanolamine (DHPE) and dipalmitoylphosphatidylethanolamine (DPPE) dispersions in concentrated sucrose solutions (1–2.4 M). It forms via a cooperative, relatively broad transition upon cooling of the Lβ gel phase of these lipids. According to the X-ray data, the transformation between Lβ and Lβ is reversible, with a temperature hysteresis of 6–10°C and a transition width of about 10°C. No specific volume changes and a very small heat absorption of about 0.05 kcal/mol accompany this transition. The Lβ−Lβ transition temperature strongly depends on the disaccharide concentration. From a value of about 10°C below the melting transition of DHPE, it drops by 25°C with decrease of sucrose concentration from 2.4 M to 1 M. The low-temperature gel phase Lβ has a repeat spacing by 8–10 Å larger than that of the Lβ gel phase and a single symmetric 4.2 Å wide-angle peak. It has been observed in 1. 1.25, 1.5 and 2.4 M solutions of sucrose, but not in 0.5 M of sucrose. The data clearly indicate that the expanded lamellar period of the Lβ phase results from a cooperative, reversible with the temperature, increase of the interlamellar space of the Lβ gel phase. Other sugars (trehalose, maltose, fructose, glucose) induce similar expanded low-temperature gel phases in DHPE and DPPE. The Lβ phase is osmotically insensitive. Its lamellar period does not depend on the sucrose concentration, while the lattice spacings of the Lα, Lβ and HH phases decrease linearly with increase of sucrose concentration. Another notable sugar effect is the induction of a cubic phase in these lipids. It forms during the reverse HH−Lα phase transition and coexists with the Lα phase in the whole temperature range between the HH and Lβ phases. The cubic phase has only been observed at sucrose concentrations of 1 M and above. In accordance with previous data, sucrose suppresses the Lα phase in both lipids and brings about a direct Lβ−HH phase transition in DHPE. A rapid, reversible gel-subgel transformation takes place at about 17°C in both DPPE and DHPE. Its properties do not depend on the sucrose concentration. The observed new effects of disaccharides on the properties of lipid dispersions might be relevant to their action as natural protectants
Benefits for visitors provided by protected areas in Bulgaria and willingness to become a conservation volunteer
Protected areas in Bulgaria (PAB) provide valuable ecosystem services. Maintaining of ecosystem health is of great importance for human wellbeing. The environmental volunteering is a valuable tool in solving local ecological problems. The main objective of the present research was to identify ecosystem services offered by PAB and attitude to participation in conservation volunteering using online survey and face-to-face interviews. Most respondents regularly use ecosystem services offered by PAB. Being well-informed about significance of maintaining ecosystem health, a lot of them declared willingness to become conservation volunteers. Online surveys could be used not only for data collection, but as also as a tool to involve people in environmental protection
A generic model for lipid monolayers, bilayers, and membranes
We describe a simple coarse-grained model which is suited to study lipid
layers and their phase transitions. Lipids are modeled by short semiflexible
chains of beads with a solvophilic head and a solvophobic tail component. They
are forced to self-assemble into bilayers by a computationally cheap `phantom
solvent' environment. The model reproduces the most important phases and phase
transitions of monolayers and bilayers. Technical issues such as Monte Carlo
parallelization schemes are briefly discussed.Comment: 4 pages, 4 figures conference paper for the CCP 2006 (Gyeongju,
Korea
Structural dynamics and physicochemical properties of pDNA/DODAB:MO lipoplexes : effect of pH and anionic lipids in inverted non-lamellar phases versus lamellar phases
Dioctadecyldimethylammoniumbromide (DODAB):Monoolein (MO) lipoplexes have mainly been studied within the range of high molar ratios of DODAB, with noticeable transfection efficiencies in the Human Embryonic Kidney (HEK, a.k.a. 293T) cell line. In thiswork,we intend to study the effect of highMOcontent on the structure and physicochemical properties of pDNA/DODAB:MOlipoplexes to achieve some correlationwith their transfection efficiency. Static/Dynamic Light Scattering and Cryo-TEM imaging were used to characterize the size/ morphology of DNA/DODAB:MO lipoplexes at different DODAB:MO contents (2:1, 1:1, 1:2) and charge ratios (CRs) (+/−). Nile Red fluorescence emission was performed to detect changes in microviscosity, hydration and polarity of DNA/DODAB:MO systems. Lipoplexes stability at physiological pH values and in the presence of
anionic lipids was evaluated by Förster Resonance Energy Transfer (FRET). Physicochemical/structural data
were complemented with transfection studies in HEK cells using the β-galactosidase reporter gene activity
assay. This work reports the coexistence of multilamellar and non-lamellar inverted phases in MO-richer
lipoplexes (DODAB:MO 1:2 and 1:4), leading to transfection efficiencies comparable to those of multilamellar (DODAB-richer) lipoplexes, but at higher charge ratios [CR (+/−) = 6.0] and without dose-effect response. These results may be related to the structural changes of lipoplexes promoted by high MO content.FEDER (037291) through POFC — COMPETEFundação para a Ciência e a Tecnologia (FCT) - SFRH/BD/46968/2009 (PhD grant), PEst-C/BIA/UI4050/2011(CBMA), PEst-C/FIS/UI0607/2011 (CFUM)
Sub-wavelength infrared imaging of lipids
Infrared absorption spectroscopy of lipid layers was performed by combining optics and scanning probe microscopy. This experimental approach enables sub-diffraction IR imaging with a spatial resolution on the nanometer scale of 1, 2-dioleoyl-sn-glycero-3-phosphocholine lipid layers
First record of the Balkan-Anatolian crested newt (Triturus ivanbureschi Arntzen & Wielstra, 2013) on the territory of the Nature Park “Shumensko plato”
In a four-year monitoring period, numerous permanent and temporary water
basins on the territory of the Habitat Protected Site BG0000382 and the Nature Park
“Shumensko Plato” (NE Bulgaria) were identified as possible habitats for amphibians. We
inspected the water bodies for presence of Urodelas, included in the inventory
documentation of the protected territories. Despite intense field surveys and use of traps, we
were able only recently to identify one specimen of the Balkan-Anatolian crested newt. This
is the first official record of the species for the protected site
Erfahrungen aus der Evaluationsplanung eines Aussteigerprogramms: Voraussetzungen für Wirksamkeitserfassung in der tertiären Extremismusprävention
Das Aussteigerprogramm Islamismus des Landes Nordrhein-Westfalen (API) und der Forschungsverbund PrEval bereiten gemeinsam die Ausschreibung einer wirkungsorientierten Evaluation des API-Programms vor. Im vorliegenden Report beschreiben die Autor:innen das notwendige dialogische Vorgehen bei der Vorbereitung des Evaluationsprozesses und leiten daraus Empfehlungen für die beteiligten Evaluationsakteure ab. Diese systematische Reflexion über die Vorbereitung eines wirkungsorientierten Evaluationsdesigns bietet eine Orientierungshilfe für Auftraggebende von Evaluationen, Evaluierende, evaluierte Projekte und Programme, aber auch Zuwendungsgeber
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