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Acritarchs, microphytoplankton of algal protists, from the Shiala and Yong Limestone formations of the Gunji village along Kali river (upstream) of Kumaon Tethyan Himalaya, Pithoragarh district, Uttrakhand, India have been examined for the first time. It aims to test the basin-wide existence and testing the reliability of already locally established biozones from the Garhwal Tethys Himalaya, Chamoli district, Uttrakhand. The study reveals moderate to poorly preserved, matured assemblages and diversified forms of acritarchs from both formations. The assemblage includes sphaeromorphs, acanthomorphs, netromorphs, polygonomorphs, diacromorphs, herkomorphs, etc. Two palynoassemblages have been recognized each from the Shiala and Yong Limestone formations. Palynoassemblage (I) from the Shiala Formation is confirmed by one productive sample which reveals a mix of Late Ordovician and Silurian forms. The acritarchs assemblage assigned to 16 genera with at least 13 species. The acritarchs from the Yong Limestone Formation are more plentiful and diverse confirming the Palynoassemblage (II) that contains biostratigraphically significant forms of typical Silurian (Ludlow) age. This Palynoassemblage is assigned to 23 genera with 16 species. The paper also describes the possible reasons for floral difference from the same formation and basin sampled at two different localities of the Tethys Himalaya, possibly due to palaeoclimatic constraints. However, detailed work on this aspect is required. The palynoassemblages from both the formations describe morphologically non-distinct, ubiquitous, wide palaeogeographic spread and uncertain stratigraphic taxa too along with biostratigraphic significant forms. [ABSTRACT FROM AUTHOR]

A new type of cross-linked copolymer granule was synthesized via emulsion polymerization and was characterized by FTIR spectroscopy. The O-carboxymethyl-chitosan was used as emulsifier for the copolymerization of methyl methacrylate and diacetone acrylamide. The resulting copolymer latex showed good compatibility with natural rubber. Morphology and surface roughness of modified natural rubber were measured by SEM and AFM. The tensile strength of natural rubber film reaches the maximum when the amount of additive was about 4%. Glass transition temperature and aging resistance were elevated. Protein spillage dropped in ca. 5 times, which could meet the minimum of the allergy protein. [ABSTRACT FROM AUTHOR]

This paper mainly focuses on the principle component analysis (PCA) and its applications on vision based computing. The underlying mechanism of PCA given and several significant factors, involved with subspace training are discussed theoretically in detail including principle components energy, residuals assessment, and decomposition computation. The typical extensions, including probabilistic PCA (PPCA), kernel PCA (KPCA), multi-dimensional PCA and robust PCA (RPCA), have been presented with critical analysis on both mechanisms and computations. Combining with the studies on, such as, image compression, visual tracking, image recognition and super-resolution image reconstruction, PCA and its extensions applied to computer vision are critically reviewed and evaluated on the targeted issues in each application as well as the role they played at specific tasks to the characteristics, cost and suitable situations of each PCA based vision processing technique. [ABSTRACT FROM AUTHOR]

Intraosseous pneumatocysts are benign gaseous bone lesions, generally asymptomatic and incidentally discovered on X-ray. These characteristics explain why these lesions are unknown to most practitioners and their low representation in medical literature. The description of an incidentally discovered iliac pneumatocyst gives us the opportunity to provide a review of available medical literature on these frequent, but poorly known lesions. [ABSTRACT FROM AUTHOR]

Borehole 2506 drilled in the northern area of the Arkhangelsk Oblast penetrated through the Paleozoic sedimentary block isolated in the Vendian thick sequence. A diverse acritarch assemblage has been established within the depth interval of 119.9–217.5 m. The assemblage comprises more than 70 taxa, including species characteristic of the boundary interval between the Volkhov and Kunda horizons of the East European Platform (the graptolite Didymograptus hirundo Zone). Stratigraphic position of host deposits was established within the Darriwilian Stage of the Middle Ordovician. The described assemblage of microphytofossils is similar to coeval assemblages from NW Russia, Baltic region, and Scandinavia, being typical of the Baltic phytoplankton province of temperate latitudes. A great number of species in common suggests that the assemblage under consideration is correlative with coeval assemblages of southern China thus offering a possibility of remote correlation. [ABSTRACT FROM AUTHOR]

As the primary producers, acritarchs represent the base of the food chain in the Paleozoic marine ecosystem which links with the evolution of acritarchs. Based on high precision quantitative research, much information about Paleozoic marine ecosystem is provided. A quantitative analysis of Early-Middle Ordovician acritarch diversity changes in the Meitan Formation, Honghuayuan section, Tongzi, Guizhou is made and the the acritarch diversity curves are compared with sea level curves. We found that acritarch diversity changes were related to sea level changes during the Early-Middle Ordovician. Whereas sea level rose, and acritarch diversity also increased. An inshore-offshore model of acritarchs best explains the relative abundance changes of some acritarch taxa in relation to sea level changes. [ABSTRACT FROM AUTHOR]

A study was undertaken to estimate fluoride content in the groundwater in certain parts of rural Eritrea, North-East Africa, along the River Anseba. Standard procedure was adopted for fluoride detection. Results indicate elevated concentration of fluoride in groundwater. The highest concentration was found to be 3.73 mg L-1, well above the safety level for consumption. Geological basis for the high concentration of high fluoride has been established; it is presumed to be the pegmatite intrusion hosted by a granitic batholith. Extensive dental fluorosis has been observed in the population exposed to drinking water of high fluoride content. [ABSTRACT FROM AUTHOR]

Demonstrates depth zonation of Arenigian acritarchs in South China. Details on scientists which have been puzzle by the fact that characteristics offshore acritarchs occur with nearshore ones; Information acritarchs.