oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Search Results: 1 - 10 of 1837 matches for " Heinz "
All listed articles are free for downloading (OA Articles)
Page 1 /1837
Display every page Item
The Misleading Use of “Enthalpy” in an Energy Conversion Analysis  [PDF]
Heinz Herwig
Natural Science (NS) , 2014, DOI: 10.4236/ns.2014.611085
Abstract: The frequently used thermodynamic state quantity enthalpy H turns out to be very problematic when applied in an energy conversion analysis. Due to the fact that H combines two terms, the internal energy U and the product pV, the interpretation of what H means in physical terms is often obscure and leads to various misinterpretations. Several examples are given and interpreted twice,i.e.with and without referring to enthalpy.
A Phenomenological Extension of the Newtonian Gravity  [PDF]
Heinz Dehnen
International Journal of Astronomy and Astrophysics (IJAA) , 2019, DOI: 10.4236/ijaa.2019.91006
Abstract: Following the idea of our previous paper we distinguish also in the case of Newtonian gravity as in the electrodynamics between extensive and intensive field quantities. Between both, a “material’’ quantity produced e.g. by vacuum polarisations induced by the gravitational field strength itself is mediated. It acts in such a way that it amplifies the field strength in weak gravitational fields and reduces the field strength in strong gravitational fields following Lenz’s rule. Newton’s gravity is valid only in a very large intermediate range of middle field strength F\"\", F0? and F1critical field strengths). In this way dark matter and black holes may be avoidable.
Lipophilic Optical Supramolecular Nano Devices in the Aqueous Phase  [PDF]
Heinz Langhals, Tim Pust
Green and Sustainable Chemistry (GSC) , 2011, DOI: 10.4236/gsc.2011.11001
Abstract: Nano micelles of sodium dodecyl sulphate in water were prepared as local lipophilic media for the organisation of interacting chromophores. Such arrangements were controlled by peripheric substituents to operate either as isolated chromophores or as skew oriented pairs where H-type transitions cause hysochromic absorption and J-type transitions bathochromic fluorescence. As a consequence, large Stokes' shift could be obtained.
A Concept for a Novel Test for Chemical Parity  [PDF]
Heinz Langhals, Oswald Krotz
Green and Sustainable Chemistry (GSC) , 2018, DOI: 10.4236/gsc.2018.84021
Abstract: Deviations from chemical parity (PV) were evaluated with the search for very small enantiomeric excesses in a racemate prepared from non chiral materials and were detected by means of the circular dichroism (CD). Thus, intensely light-absorbing perylenebiscarboximides were attached to axially chiral biphenyls for the amplification of CD effects by exciton interactions of the adjacent chromophores. A rapidly racemising system was applied for the exclusion of artifacts and compared with an analogous with locked chirally. A very slight enantiomeric excess was detected for the (M) enantiomer. Application of the method for other systems was suggested and relations to natural products discussed.
Do Near-Solar-System Supernovae Enhance Volcanic Activities on Earth and Neighbouring Planets on Their Paths through the Spiral Arms of the Milky Way, and What Might Be the Consequences for Estimations of Earth’s History and Predictions for Its Future?  [PDF]
Heinz-Juergen Brink
International Journal of Geosciences (IJG) , 2019, DOI: 10.4236/ijg.2019.105032
Abstract: Recent observations of young volcanism on the near-Earth terrestrial planets require a new understanding. Magmatic/volcanic episodes on Venus, Mars and Mercury, as well as on Earth’s Moon, are apparently contemporaneous thermal events that accompanied increased magmatic/volcanic activity on Earth, following a 300-Myr cycle. A collateral galactic thermal source in the Milky Way appears to be needed that would predominantly affect the interior of the planets and, perhaps indirectly, Earth’s biosphere, compared to other galactic sources, such as intense cosmic rays or large, rocky bolides. The search for such a source leads to near-Earth supernovae, with their neutrino output, and to the question of whether those neutrinos could act as energy transmitters to heat up the body of Earth, and also enhance its short-term magmatic processes; for example, Cenozoic anorogenic volcanism. This observation challenges present assumptions and paradigms about Earth’s history, and requires the following reconsiderations: 1) the real origin of the end-Cretaceous mass extinction; 2) the general radioactive age determinations of rocks; and 3) geodynamic modelling using additional, external heat sources.
Periodic Signals of the Milky Way Concealed in Terrestrial Sedimentary Basin Fills and in Planetary Magmatism?  [PDF]
Heinz-Jürgen Brink
International Journal of Geosciences (IJG) , 2015, DOI: 10.4236/ijg.2015.68067
Abstract: Long periodic geodynamic processes with durations between 150 and 600 Million years appear to be in phase with similar galactic cycles, caused by the path of the solar system through the spiral arms of the Milky Way. This path is assumed by some authors to cause climate change due to cosmic ray fluctuations, affecting the cloud formation and the related albedo of the Earth, which periodically lead to glaciations every 150 Ma. With the glaciations, the sea level fluctuates accordingly. Subsequently, the varying sizes of shallow seas are causing periodic changes of the Moon’stidal dissipation, which affects presumably other geodynamic processes on the Earth. The Moonmay therefore synchronize directly or indirectly long periodic Phanerozoic cycles (sea level, orogeny, magmatism, sedimentation, etc.) with the Milky Way. As sea level fluctuations, orogeny, sedimentation and magmatism can be described as members of a geodynamic feedback system; no apparent reasons appear to be required to assign a cause of the cyclicity to agents outside of thegalactic-climatically synchronized Earth-Moon system. However, recent observations of youngvolcanism on the near Earth terrestrial planets may require a new understanding. Magmatic/volcanic episodes on Venus, Mars and Mercury as well as on the Earth’s Moon are apparently contemporaneous thermal events accompanying increased magmatic/volcanic activities on theEarth,following a 300 myr cycle. Therefore, a collateral galactic thermal source within the Milky Way
Multi-minicore Disease
Heinz Jungbluth
Orphanet Journal of Rare Diseases , 2007, DOI: 10.1186/1750-1172-2-31
Abstract: Multi-minicore Disease; Minicore myopathy; Multicore myopathy; Multiminicore myopathy; Minicore myopathy with external ophthalmoplegia; Multicore myopathy with external ophthalmoplegia; Multiminicore disease with external ophthalmoplegiaMulti-minicore Disease (MmD) is an inherited neuromuscular disorder defined by a) multiple areas with reduced oxidative activity running along an only limited extent of the longitudinal axis of the muscle fibre ("minicores") and b) clinical features of a congenital myopathy.The condition was originally reported in a family with two affected siblings and suggestive histopathological findings [1]; various different designations ("Minicore myopathy", "Multicore myopathy", "Multiminicore myopathy", "Minicore myopathy with external ophthalmoplegia", "Multicore myopathy with external ophthalmoplegia", "Multiminicore disease with external ophthalmoplegia") have been assigned to cases with similar histopathological features and reflect the wide variability of both core appearance on muscle biopsy and associated clinical findings.Epidemiological data are only available for the congenital myopathies as a group but not for individual conditions. The incidence of all congenital myopathies is estimated at around 0.06/1,000 live births, or onetenth of all cases of neuromuscular disorders [2]. Regional studies in Northern Ireland [3] and Western Sweden [4] suggest a prevalence between 3.5 – 5.0/100,000 in a Paediatric population.Forms of MmD due to recessive mutations in the selenoprotein N (SEPN1) gene are probably rarer than those due to mutations in the skeletal muscle ryanodine receptor (RYR1) gene (personal observation), as mutations in the latter gene appear to be the most common genetic cause of a wide variety of congenital myopathies including central core disease (CCD) [5], certain forms of centronuclear myopathy (CNM) [6] and specific subgroups of MmD.Presentation of MmD is usually in infancy or childhood with hypotonia or proximal weakne
Central core disease
Heinz Jungbluth
Orphanet Journal of Rare Diseases , 2007, DOI: 10.1186/1750-1172-2-25
Abstract: Central core diseaseCentral core disease (CCD) (MIM * 117000) [1] is an inherited neuromuscular disorder defined by a) areas with reduced oxidative activity running along the longitudinal axis of the muscle fibre ("central cores") and b) clinical features of a congenital myopathy.CCD was originally reported in a family with congenital hypotonia, non-progressive weakness and central areas of amorphous appearance within muscle fibres stained with the modified Gomori trichrome technique [2]. The term CCD was introduced later [3] and reflects the characteristic absence of oxidative enzyme activity in the core area due to mitochondrial depletion [4].Epidemiological data are only available for the congenital myopathies as a group but not for specific conditions. The incidence of all congenital myopathies is estimated at around 6.0/100,000 live births, or onetenth of all cases of neuromuscular disorders [5]. Regional studies in Northern Ireland [6] and Western Sweden [7] suggest a prevalence between 3.5 – 5.0/100,000 in a paediatric population.CCD is probably the most common congenital myopathy; the condition is likely to be under recognised considering that some individuals with suggestive clinical features and an identical genetic background do not necessarily exhibit the characteristic histopathological features, particularly when biopsied at an early age.Presentation of dominantly inherited CCD is typically in infancy with hypotonia or in early childhood with motor developmental delay [8]; however, marked clinical variability, often within the same family, has been recognised [9-12]. Muscle stiffness and weakness on exertion are recognised presenting features [13,14]. More severe presentations within the range of the foetal akinesia sequence [15] have been reported associated with recessive inheritance. There is no association between the number of cores on muscle biopsy and the degree of muscle weakness [16].Distribution of weakness is typically proximal with prominen
Alveolar epithelial type II cell: defender of the alveolus revisited
Heinz Fehrenbach
Respiratory Research , 2001, DOI: 10.1186/rr36
Abstract: As early as 1954, CC Macklin had postulated some of the most important functions of the great pneumocyte, ie the pneumocyte type II or alveolar epithelial type II (AE2) cell (Fig. 1) [1]. Macklin presumed that these cells secrete material that provides low surface tension, enhances clearance of inhaled particles, is bacteriostatic, and helps prevent transudation of interstitial fluid into the alveolus. He further reported that these cells proliferate after lung injury by osmium tetroxide fumes [1]. By 1977, enough data had been collected to stimulate Mason and Williams [2] to formulate the concept of the AE2 cell as a "defender of the alveolus". It was established that the main functions were synthesis and secretion of surface-active material, hyperplasia in reaction to alveolar epithelial injury, and serving as the progenitor for AE1 cells, which form the epithelial component of the thin air–blood barrier. Nevertheless, several "postulated" functions were listed, for example, secretion of other substances, modulation of the alveolar hypophase, and adaptation in response to lung injury [2]. In the following 23 years, an increasing number of studies revealed many more details concerning the role of the AE2 cell in surfactant delivery and alveolar epithelial repair (see Supplementary Table 1) and a considerable number of supplementary functions have been established (see Supplementary Table 2). This review covers most aspects of current knowledge of AE2 cell functions.Although the presence of a surface-active agent in the mammalian lung was postulated by von Neergaard as early as 1929 [3], it was the work of Pattle [4] and Clements [5] that opened a new scientific field (for review of historical aspects, see [6]). This surface-active agent, termed surfactant, was characterised in numerous biochemical studies of bronchoalveolar lavage (BAL) material and is now known to be composed of ? 90% (mass) lipids (with ? 80–90% phospholipids) and of ? 10% proteins. Its compositi
The Azadirachtins: potent insect growth inhibitors
Rembold, Heinz;
Memórias do Instituto Oswaldo Cruz , 1987, DOI: 10.1590/S0074-02761987000700013
Abstract: in the course of their coevolution with insects, plants have learnt to protect themselves by chemical means. semiochemical act as antifeedants or deterrents, others by disrupting growth and development. by use of the epilachna varivestis bioassay we isolated from azadirachta indica seed a group of triterpenoids which interfee with larval growth and development in ppm range. main components are the azadirachtins a and b with identical biological activity. various other azadirachtins were obtained, either as minor seed components or by chemical modification of the naturally occuring compounds. structure vs. activity relation studies enabled us to postulate a basic structural element that should still be biologically active and with much simpler chemical structure than natural compounds. what underlies the biological activity of these insect growth inhibitors? their interference with the hormonal regulation of development and reproduction has been studied in locusta migratoria and rhodnius prolixus. in addition, tritiated dihydroazadirachtin a was used. with this approach, a precise correlation between administered dose, resulting effects, and retention of the compound was established. the azadirachtins either interrupt, delay, or deviate whole developmental programs. results from these studies provide another chemical probe for studies in insect endocrinology and physiology.
Page 1 /1837
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.