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Igor Dakskobler and Livio Poldini

Abstract

We conducted a phytosociological study of alpine grasslands with dominant Luzula alpinopilosa in the Julian and Carnic Alps. Based on a comparison with similar communities elsewhere in the Alps we described a new association Junco jacquinii-Luzuletum alpinopilosae, which we classify into the provisional alliance Doronico glacialis-Juncion jacquinii, order Festucetalia spadiceae and class Juncetea trifidi. The new association characterises moist shady grasslands in gullies and on ledges on limestone admixed with marlstone and chert, in the elevation range between 2000 and 2500 m, where the snow cover persists for extended periods. We distinguish three subassociations: -galietosum anisophyllae (the most calcareous form), -potentilletosum aureae (typical form) and -leucanthemopsietosum alpinae (acidophilic form on Werfen sandstones in the Carnic Alps, which is the most similar to the stands of the association Luzuletum alpinopilosae from the Central Alps).

Open access

Hippolyte Hounnon and Klaus Denecke

Abstract

A variety of semirings is said to be solid if each of its identities is satisfied as hyperidentity. There are precisely four solid varieties of semirings. Each of them contains every derived algebra, where the both fundamental operations are replaced by arbitrary binary term operations. If a variety contains all linear derived algebras, where the fundamental operations are replaced by term operations induced by linear terms, it is called linear-solid. We prove that a variety of semirings is solid if and only if it is linear-solid.

Open access

Zdeněk Vacek, Stanislav Vacek, Jiří Slanař, Lukáš Bílek, Daniel Bulušek, Igor Štefančík, Ivo Králíček and Karel Vančura

Abstract

In time of climate change, close-to-nature silviculture is growing in importance as a tool for future forest management. The paper study the tree layer and natural regeneration of monospecific Norway spruce (Picea abies [L.] Karst.), trough mixed spruce-beech to dominant European beech (Fagus sylvatica L.) forests in Jizerské hory Mts., the Czech Republic. In the locality, shelterwood and selection system have been applied since 2000. The research objectives were to evaluate production parameters, structural diversity, species richness, natural regeneration dynamics and radial growth of individual tree species in relation to climatic factors and air pollution. The stand volume on permanent research plots amounted to 441 – 731 m3 ha−1 in initial stage of transformation. Natural regeneration showed high expansion of beech and decrease of spruce compared to mature tree species composition. Radial growth of spruce was in significant negative correlation with SO2 and NOX concentrations compared to no effect on beech increment. Moreover, spruce was more sensitive to significant years with extreme low radial growth. Beech was more stable in radial growth. Spruce was more resistant to air pollution and climatic stress in mixed stands. Low temperature was limiting factor of radial growth together with climate extremes (such as strong frosts and more frequent droughts) and biotic factors (bark beetle, beech scale). Close-to-nature management supporting admixed tree species should lead in future to diversification of stand structure toward higher species, spatial and age structure to mitigate negative effect of climatic change.

Open access

Shan Xiong, Jinglai Li, Yanling Mu and Zhenqing Zhang

Abstract

Morroniside is one of the most important iridoid glycosides from Cornus officinalis Sieb. et Zucc. In the present study, the pharmacokinetics and bioavailability studies of morroniside were conducted on Sprague-Dawley (SD) rats. A rat in situ intestinal perfusion model was used to characterize the absorption of morroniside. Caco-2 cells were used to examine the transport mechanisms of morroniside. The pharmacokinetic study of morroniside exhibited linear dose-proportional pharmacokinetic characteristics and low bioavailability (4.3 %) in SD rats. Its average P eff value for transport across the small intestinal segments changed from (3.09 ± 2.03) × 10−6 to (4.53 ± 0.94) × 10−6 cm s−1. In Caco-2 cells, the P app values ranged from (1.61 ± 0.53) × 10−9 to (1.19 ± 0.22) × 10−7 cm s−1 for the apical to basolateral side and the P ratio values at three concentrations were all lower than 1.2. Morroniside showed poor absorption and it might not be a specific substrate of P-glycoprotein (P-gp).

Open access

Andra Chiriac, Camelia Badea and Cristian Băicuş

Abstract

Giant cell arteritis is a common systemic vasculitis affecting the elderly, with maximum prevalence in the 7th decade of age, targeting aortic derived medium and large vessels of the neck and head. Diagnosis is established on a biopsy specimen of the temporal artery wall, through pathological confirmation of panarteritis, typically characterized by mononuclear cell infiltrate, with the 1990 ACR criteria often used in clinical practice.

We present the case of a patient with a new onset headache and systemic inflammation, did not fulfil the classical diagnostic criteria, nor did the temporal artery biopsy (TAB) provide a positive result. However, the ultrasonographical features, clinical evolution and response to corticosteroid therapy confirmed the diagnosis. This patient had bilateral presence of the halo sign on color duplex ultrasonography (CDUS), cited as a highly specific feature, when compared to the ACR criteria as a standard reference. We employed its positive likelihood-ratio (LR+) of 43 as previously estimated, while considering a low pre-test probability for a positive diagnosis (15%), to calculate a post-test probability of 88%, leading to our decision to treat him as having giant cell arteritis. Remission of the headache and rebound phenomena when tapered off steroid therapy substantially contributed to the positive diagnosis, underlining the importance of future studies needing to use clinical evolution as a standard of reference.

Open access

M. Asad and H.U. Rahim

Abstract

The lower Indus basin is one of the prolific basins in Pakistan in which the C-interval of lower Goru formation act as a reservoir. With the help of petrophysical interpretation production zone is recognized and also porosity is calculated at the reservoir level. Through porosity we are able to calculate Ksat. A model based inversion of 2D seismic inversion was performed to ascertain three dimensional dispersion of acoustic impedance in the investigation zone and we have recognized new areas where porosity distribution is maximum and site which is suitable for new well. Porosity and Acoustic impedance are typically contrarily relative to each other. Presently porosity can be anticipated in seismic reservoir characterization by utilizing acoustic impedance from seismic inversion far from well position.

Open access

Sara Tomczak, Hanna Gorejko and Wiktor Dróżdż

Abstract

Introduction: Amyotrophic lateral sclerosis is a progressive neurodegenerative disease with undetermined etiology. Due to diverse symptomatology, it requires a thorough differential diagnosis, with consideration of conversion disorders. The presented thesis describes a case of a young man hospitalized in the Department of Psychiatry in order to verify the possible psychogenic basis of his symptoms, which previously were considered to be a manifestation of neurological disease with an unfavorable prognosis.

Aim: The aim of the thesis is to raise the issue of a multidisciplinary approach to diagnostic process in medicine, as well as taking into account the legitimacy of including psychiatrists, psychologists, and psychotherapists in diagnostic teams.

Case study: We present a case report of a man who has been experiencing progressive feeling and walking problems for the past several years, which originally suggested a neurological or rheumatological disease. Earlier observations and medical tests had led to a diagnosis of amyotrophic lateral sclerosis. After several years, the diagnosis was excluded, and the patient was referred to the Department of Psychiatry to determine the possible psychogenic basis of his symptoms. Diagnostic methods used during the patient’s hospitalization confirmed the conversational nature of his symptoms, and both pharmacological and psychotherapeutic treatment caused reduction of severity of his symptoms and allowed him for a gradual return to independent functioning.

Conclusion: Analysis of the collected data, including patient’s life history and a course of his treatment, indicates the validity of a holistic approach to medical problems, which implies the inclusion of specialists in the field of psychiatry, psychology, as well as psychotherapists in diagnostic teams. Such a multidimensional view of the patient and the source of his symptoms may allow for faster diagnosis and may also contribute to reducing the risk of making mistakes such as an incorrect assessment of factors triggering the disease process.

Open access

Aleksandar Golijanin and Vladimir Malbašić

Abstract

The Durmitor flysch complex represents a specific formation both in lithological and engineering geological sense. In the engineering geological sense this lithological formation is characterized by anisotropic and heterogeneous geotechnical properties, which depend on the dominant members within each individual package, as well as their spatial position.The Durmitor flysch complex consists of five superposition bed packages, which are mutually substantially different in their lithological, hydrogeological and geotechnical properties. For the first time in geological literature, this paper distinguishes five types of terrain construction within the Durmitor flysch complex. Contemporary geodynamic processes and their character within the flysch formation are defined. Particular emphasis is put on landslides, which represent a contemporary geodynamic phenomenon with certain specificities.