Hough Transform to Study the Magnetic Confinement of Solar Spicules

One of the important parameters of the ubiquitous spicules rising intermittently above the surface of the Sun is the variation of spicule spline orientation with respect to the solar coordinates, presumably reflecting the focusing of ejection by the coronal magnetic field. Here we first use a method of tracing limb spicules using a combination of second derivative operators in multiple directions around each pixel to enhance the visibility of fine linear part of spicules. Furthermore, the Hough transform is used for a statistical analysis of spicule orientations in different regions around the solar limb, from the pole to the equator. Our results show a large difference of spicule apparent tilt angles in regions of: 1) the solar poles, 2) the equator, 3) the active regions and 4) the coronal holes. Spicules are visible in a radial direction in polar regions with a tilt angle <20°. The tilt angle is even reduced inside a coronal hole (open magnetic field lines) to 10 degrees and at the lower latitude the tilt angle reaches values in excess of 50 degree. Usually, around an active region they show a wide range of apparent angle variations from –60 to +60 degrees, which is in close resemblance to the rosettes made of dark mottles and fibrils seen in projection with the solar disk.

Mode coupling in solar spicule oscillations

In a real medium which has oscillations, the perturbations can cause an energy transfer between different modes. A perturbation, which is interpreted as an interaction between the modes, is inferred to be mode coupling. The mode coupling process in an inhomogeneous medium such as solar spicules may lead to the coupling of kink waves to local Alfven waves. This coupling occurs in practically any conditions when there is smooth variation in density in the radial direction. This process is seen as the decay of transverse kink waves in the medium. To study the damping of kink waves due to mode coupling, a 2.5-dimensional numerical simulation of the initial wave is considered in spicules. The initial perturbation is assumed to be in a plane perpendicular to the spicule axis. The considered kink wave is a standing wave which shows an exponential damping in the inhomogeneous layer after the mode coupling occurs.

Guadalupian (Middle Permian) Radiolarian and Sponge Spicule Faunas from the Bancheng Formation of the Qinzhou Allochthon,South China

The Gujingling （古井岭） Section in Xiaodong （小董）, Guangxi （广西） Zhuang Autonomous Region, China, consists of cherts and siliceous siltstones, which belongs to the Bancheng （板城）Formation of the Qinzhou （钦州） allochthon. Three successive radiolarian assemblage-zones related to the Guadalupian （Middle Permian） appear in the section in the following ascending order： Pseudoalbaillella sp. aff. Pseudoaibailleila longicornis-Pseudoalbaillella fusiformis, Follicucuilus monacanthus, and Follicucuilus scholasticus-Foilicucullus porrectus. The radiolarian content in this section is generally greater than that of sponge spicules. The radiolarian fauna commonly consists of abundant Albaillellaria and spherical radiolaria with minor Latentifistularia and Entactinaria. The sponge fauna is composed mainly of hexactinellids with minor demosponges. These siliceous fossil faunal features, comparable with those in a deep basin of the western belt of the Phosphoria Basin in the western United States, indicate that the Bancheng Formation in the Gujingling Section was deposited in a basin deeper than 1 000 m. The siliceous siltstones in the section are characterized by inclusion of silt-sized quartz and no inclusion of sand-sized materials, suggesting that the Gujingling Section was located at least a few hundred kilometers from the South China Block in the Guadalupian.

Extinction pattern and process of siliceous sponge spicules in deep-water during the latest Permian in South China

Diverse and abundant siliceous sponge spicules were found in the latest Permian beds, Dongpan and Ma’anying sections, South China, including 52 types and 85 forms. Further investigation on these spicules allows us to understand extinction patterns and pro

Biomorphic analysis as a basis for paleoenvironmental reconstruction

A definition for biomorphic analysis is suggested. The objects of analysis - biomorphs(phytoliths, sponge spicules) - are characterized with respect to their diagnostic features andmethods of data interpretation. The possibility of to include studies into the general system ofpaleoenvironmental and palaeosols interpretations from biomorphic analysis is substantiated withconcrete examples.

Antagonistic activity of marine sponges associated Actinobacteria

Objective:To focus on the isolation and preliminary characterization of marine sponges associated Actinobacteria particularly Streptomyces species and also their antagonistic activities against bacterial and fungal pathogens.Methods:The sponges were collected from Kovalam and Vizhinjam port of south-west coast of Kerala,India.Isolation of strains was carried out from sponge extracts using international Streptomyces project media.For preliminary identification of the strains,morphological(mycelial colouration,soluble pigments,melanoid pigmentation,spore morphology),nutritional uptake(carbon utilisation,amonoacids influence,sodium chloride tolerance),physiological(pH,temperature)and chemotaxonomical characterization were done.Antimicrobial studies were also carried out for the selected strains.Results:With the help of the spicule structures,the collected marine sponges were identified as Callyspongia diffusa,Mycale mytilorum,Tedania anhelans and Dysidea fragilis.Nearly 94 strains were primarily isolated from these sponges and further they were sub-cultured using international Streptomyces project media.The strains exhibited different mycelial colouration(aerial and substrate),soluble and melanoid pigmentations.The strains possessed three types of sporophore morphology namely rectus flexibilis,spiral and retinaculiaperti.Among the 94 isolates,seven exhibited antibacterial and antifungal activities with maximal zone of inhibition of 30 mm.The nutritional,physiological and chemotaxonomical characteristic study helped in the conventional identification of the seven strains and they all suggest that the strains to be grouped under the genus Streptomyces.Conclusions:The present study clearly helps in the preliminary identification of the isolates associated with marine sponges.Antagonistic activities prove the production of antimicrobial metabolites against the pathogens.Marine sponges associated Streptomyces are universally well known for their synthesis of many bioactive compounds such as antibiotics,enzymes,enzyme inhibitors and food grade pigments.They also have certain biotechnological applications like probiotics and single cell proteins.These marine Streptomyces bioactive metabolites can be the futuristic solution for the dreadful diseases.