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The bicarbonate buffer is considered as the most biorelevant buffer system for the simulation of intestinal conditions. However, its use in dissolution testing of solid oral dosage forms is very limited. The reason for this is the thermodynamic instability of the solution containing hydrogen carbonate ions and carbonic acid. The spontaneous loss of carbon dioxide (CO2) from the solution results in an uncontrolled increase of the pH. In order to maintain the pH on the desired level, either a CO2 loss must be completely avoided or the escaped CO2 has to be replaced by quantitative substitution, i.e. feeding the solution with the respective amount of gas, which re-acidifies the buffer after dissociation. The present work aimed at the development of a device enabling an automatic pH monitoring and regulation of hydrogen carbonate buffers during dissolution tests.  相似文献   
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International Journal of Peptide Research and Therapeutics - The progressive damage of human articular cartilage is associated with loss of integrity of its extracellular matrix components. Their...  相似文献   
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Vegetation History and Archaeobotany - The Eemian interglacial represents a natural experiment on how past vegetation with negligible human impact responded to amplified temperature changes...  相似文献   
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Pathogens carried by ticks pose a threat to both human and animal health across the world. Typically associated with rural landscapes, ticks appear to adapt well to life in urban recreational areas. Although Dermacentor reticulatus is commonly found across Europe, data on the prevalence of pathogens in this tick species, in an urban environment, are very limited. PCR was used to examine 368 D. reticulatus individuals collected in the Zwierzyniecki Forest Nature Reserve in Bia?ystok, Poland. In total, 10.3% of ticks were infected, with Babesia spp. (9.2%), Anaplasma phagocytophilum (0.8%) and Borrelia burgdorferi sensu lato (0.3%). Rickettsia spp., Bartonella spp., and Coxiella burnetii were not detected. Sequence analysis for Babesia-positive samples identified 79.4% of them as Babesia canis, 8.8% as Babesia microti, 5.9% as Babesia spp., 2.9% as Babesia venatorum, and 2.9% as Babesia vogeli. Results obtained in this study indicate that D. reticulatus ticks found within the urban premises of the study area are infected with at least three pathogens and therefore are an important factor in public health risk for tick-borne diseases.

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A statistical analysis of the variation in contents with the size of the current known smallest genomes, N. deltocephalinicola, C. ruddii, N. equitans, and M. genitalium, enabled the indication of a minimal set of codons capable of naturally building a modern-type free-living unicellular organism in an early stage of evolution. Using a linear regression model, the potential codon distribution in the minimal natural cell was predicted and compared to the composition of the smallest synthetic, JCVI-Syn3.0. The distribution of the molecular weight of potentially coded amino acids was also calculated. The main differences in the features of the minimal natural cell and H. Sapiens genome were analyzed. In this regard, the content percentage of respective amino acids and their polarization charge properties were reported and compared. The fractions of occurring nucleotides were calculated, too. Then, the estimated numbers of codons in a minimal natural cell were related to the expected numbers for random distribution. Shown increase, or decrease in the contents, relative to the calculated random filling was related to the evolutionary preferences, varying with the subsequent eras of the evolution of genetic code.

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The dry climate that prevailed during the Triassic period in the eastern part of the Central European Basin was interrupted by several humid episodes of varying durations. One of them was the Carnian Pluvial Episode (CPE), which took place in the late Julian (early Carnian age) and is confined to Camerosporites secatus and Aulisporites astigmosus palynological zones. CPE is marked by a significant change in the qualitative and quantitative composition of spore-pollen assemblages from mostly xerophytic species preserved in the upper part of the Grabfeld Formation (“Lower Gipskeuper”) to hygrophytic forms, which dominate in the Stuttgart Formation (“Schilfsandstein”). Changes in climate towards more humid conditions have been documented palynologically and sedimentologically, and analyzed utilizing quantitative spore-pollen analysis and Principal Component Analysis (PCA) of miospores occurring in core material from Poland. In all the studied boreholes, a shift from dry to wet climate is observed at the boundary between the Grabfeld Formation and the Stuttgart Formation, which matches the data from other European regions.  相似文献   
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