Gyrations: The Missing Link Between Classical Mechanics with its Underlying Euclidean Geometry and Relativistic Mechanics with its Underlying Hyperbolic Geometry

Being neither commutative nor associative, Einstein velocity addition of relativistically admissible velocities gives rise to gyrations. Gyrations, in turn, measure the extent to which Einstein addition deviates from commutativity and from associativity. Gyrations are geometric automorphisms abstracted from the relativistic mechanical effect known as Thomas precession

Perspectivas de la empresa y la economía mexicana frente a la reestructuración productiva

1 archivo PDF (404 páginas)Este texto se presenta una reflexión de investigadores de la UAM, así como de otras Instituciones de Educación Superior respecto al marco en el que se han desenvuelto las empresas mexicanas en los últimos años, así como del desarrollo en algunos de sus sistemas organizacionales. PALABRAS CLAVE: Mexico Economic policy 1970-1994

Albumin and mammalian cell culture: implications for biotechnology applications

Albumin has a long historical involvement in design of media for the successful culture of mammalian cells, in both the research and commercial fields. The potential application of albumins, bovine or human serum albumin, for cell culture is a by-product of the physico-chemical, biochemical and cell-specific properties of the molecule. In this review an analysis of these features of albumin leads to a consideration of the extracellular and intracellular actions of the molecule, and importantly the role of its interactions with numerous ligands or bioactive factors that influence the growth of cells in culture: these include hormones, growth factors, lipids, amino acids, metal ions, reactive oxygen and nitrogen species to name a few. The interaction of albumin with the cell in relation to these co-factors has a potential impact on metabolic and biosynthetic activity, cell proliferation and survival. Application of this knowledge to improve the performance in manufacturing biotechnology and in the emerging uses of cell culture for tissue engineering and stem cell derived therapies is an important prospect

Potentially pathogenic fungi in the waters of the Charzykowskie Lake in Zaborski Landscape Park

The occurrence of potentially pathogenic fungal strains in the Charzykowskie Lake and runnels flowing into and out of it was investigated. The study material was obtained in 2005 and in 2006, in the periods of spring intermix and summer stagnation, and in 2005 in the period of autumn intermix. The fungi found in the Charzykowski Lake belonged to 5 genera: Rhodotorula (R. minuta, R.rubra and R. glutinis), Cryptoccocus (C. neoformans, C. laurentii, C. terreus and C. laurentii), Candida (C. inconspicua, C. lusitaniae, C. tropicalis, C. pelliculosa, C. kefir, C. glabrata, C. inconspicua, C. parapsilosis, C. ciferrii and C. colliculosa), Trichosporon (T. cutaneum) and Klockera (K. apiculata). The fungi found in runnels flowing into and out of the Charzykowskie Lake belonged to 4 genera: Rhodotorula (R. rubra and R. glutinis), Cryptoccocus (C. laurentii, C. neoformans, C. albidus and C. terreus), Candida (C. colliculosa, C. lusitaniae, C. tropicalis, C. pelliculosa, C.cifferii, C. glabrata) and Trichosporon (T. cutaneum)

Some biochemical properties of fungi from genera Rhodotorula and Trichosporon isolated from Sulejow Reservoir bath water

The hydrolytic activity of Rhodotorula and Trichosporon strains isolated from Sulejów Reservoir water and sediments were studied. Also tolerance of high concentrations of natrium chloride and biogenic compounds was evaluated. Fungi from genera Rhodotorula and Trichosporon showed the activity of 12 and 10 from 19 hydrolases of API Zym test, respectively. Tolerance tests showed high resistance of Rhodotorula glutinis to hypertonic saline solutions and very high resistance of both Rhodotorula and Trichosporon strains to nitrate, ammonium and phosphate compounds. These properties of fungi may influence the distribution and the quantity of fungi in aquatic reservoirs

Prevalence of potentially pathogenic fungi in the bathing sites of the Sulejow Reservoir

Progressive degradation of water ecosystems may contribute to the propagation of fungi pathogenic to humans and animals. The aim of this study was a quantitative evaluation and identification of species of potentially pathogenic fungi in the littoral zone of the Sulejów Reservoir used as recreation site. We studied samples of surface water and sediments collected from 6 sampling sites of the reservoir in the years 2000 and 2001. In 2000, fungi were isolated from 82.7% of samples, while in 2001 from as many as 95.4%. There were 28 species representing genera: Candida, Cryptococcus, Geotrichum, Kloeckera, Rhodotorula, Saccharomyces, and Trichosporon. The most common species were Rhodotorula glutinis and Candida guilliermondii. The density of the population of identified species depended on the season and sampling site and ranged from 80 to 328000 cells/dm³ (also uncountable growth). The waters of the Sulejów Reservoir may be a covenient place of anamorphic developmental forms, for the 15 cultured species which can also propagate in humans and other mammals

ACTIVITY OF ACID ASPARTIC PROTEINASE CANDIDA STRAINS ISOLATED FROM PALATINE TONSILS*

We have evalueated the activity of acidous asparagine protease in 48 strains of Candida isolated from homogenates of palatine tonsils from 116 patients after tonsilectomy. Strains most frequently isolated were C. albicans (66.7±6.8 %) and C. tropicalis (14.6±5.09 %). The range of proteolysis zone for Candida strains was 4.6 to 12.5 mm. Over 60% of the studied strains showed high and very high proteolytic activity (>6.6 mm) and the remaining strains with showed moderate activity (4.6-6.5). There were no strains with low medium activity (to 4.5 mm zone). The range of the number of rosettes E formed by lymphocytes obtained from the studied tonsils was 0-268.3. Lymphocytes isolated from 70 % of tonsils infected with Candida formed only 0-130 rosettes E; in the remaining cases the number ranged between 131 and 220. The number of lymphocytes T forming rosettes E isolated from palatine tonsils from patients not infected with fungi was 2.5 times higher. There was no correlation between the size of proteolysis zone and the number of rosettes E

HYDROLYTIC ACTIVITY YEAST-LIKE FUNGI STRAINS ISOLATED FROM SULEJÓW RESERVOIR WATER

We have investigated the hydrolytic activity of 21 species of yeast-like fungi from Candida genus and l species of yeast S. cerevisiae isolated from Sulejów Reservoir water. The activity of hydrolytic enzymes of the studied fungi was different than that of standard strains and also of fungi isolated from patients. This difference demonstrates the capability of the studied fungi to adapt to various environmental conditions

EVALUTION OF ACTIVITY OF ACID ASPARTIC PROTEINASE IN CANDIDA STRAINS . ISOLATED FROM ORAL CAVITY OF PATIENTS WITH INCREASED RISK OF MYCOSIS

We have evaluated the activity of acid aspartic protease in 195 strains of Candida isolated from the oral cavity of three groups of patients. The first group comprised patients with cancer of the larynx qualified for surgery, the second- patients with neoplastic disease (Hodgkin's disease, lymphoma, acute granulocytic leukaemia, lymphatic leukaemia, lung cancer, multiple myeloma, stomach cancer, breast cancer) who were not treated, the third group- patients with neoplastic diseases treated by chemotherapy. The strains of fungi were differentiated using API 20C and Api 20C AUX tests according to the protocol adopted at the Department of Medical Parasitology and Biology, Medical University of Łódż. The activity of acid protease was studied by Staib method in Rózga modification. Almost all strains showed high and very high proteolytic activity. The rang of proteolysis zone of Candida strains from the three groups of patients varied from 2,5 to 12,5 mm. We have found the mean proteolytic zones of strains isolated from groups Iand III differed statistically significantly (p<0,001). Similarly, statisticall sihnificant difference was seen between these parameters for groups II and III (p<0,05), while there was no difference between strains from group I and II