Crystal cored optical waveguides

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Morphology of the fertile leaves of the lomariopsidaceae, with special reference to the venation

Fertile pinnae of thirty-one species of the eight genera of Lomariopsidaceae studied have the lamina variously reduced, in some cases to narrow wings on either side of the midrib. The lamina is either broad, thin, and with the venation conspicuous on the surface, or narrow, fleshy, and with hidden venation. The mesophyll is undifferentiated and consists of thin-walled parenchyma which possesses collapsible walls in some species. Intercellular air spaces are inconspicuous in most species. The epidermal cells are usually thin-walled, chlorophyllous and dorsiventrally flattened. The midrib has two or three vascular strands which unite into one in the anterior half of the lamina. Distinct sclerenchyma tissue is absent: a few layers of thick-walled hypodermal cells occur in the midrib region in some. Venation of the fertile pinna is almost similar to that of the sterile pinnae in Bolbitis and Lomagramma (both reticulate), and in Egenolfia, Elaphoglossum and Thysanosoria (all free-veined). The fertile pinnae of Arthrobotrya, Lomariopsis and Teratophyllum usually possess a reticulate venation, though the sterile pinnae are free-veined. A set of special veins supplying the sporangia is found in addition to the 'normal' venation in many species except Elaphoglossum and Thysanosoria. The special venation is variously developed in the different species of each genus; it consists of a set of veins close to the lower epidermis of the lamina and connected to the 'normal' veins at intervals: in some cases the special veins form extensive reticulations independent of the 'normal' venation. The two sets of veins are at different planes, one above the other. The special venation is not connected directly to the midrib and often has a longitudinal vein running parallel to the midrib on either side. In all genera, except Thysanosoria which has discrete sori restricted to the vein tips, sporangia are acrostichoid in distribution. They are of the common leptosporangiate type. The sporangial stalk is slender and long in all, except Lomagramma and Lomariopsis in which it is short and stout. The stalk is three cells thick, the third row developed secondarily as a protrusion of the basal wall cell of the capsule in continuation of the stomium. Distinct paraphyses are absent, except in Arthrobotrya, Lomagramma and Teratophyllum. The spores are bilateral, monolete and ranging in size from 22 × 33 μ(Bolbitis spp., Elaphoglossum spp.) to 90 × 125 μ(Lomariopsis intermedia). The exine is smooth except in Lomagramma, Thysanosoria (both granulose) and Lomariopsis spp. (spinulose). Lomagramma and Thysanosoria are perine-less; all others are perinate, with the perine bearing characteristic reticulate ornamentation in all except Bolbitis and Elaphoglossum

Gametophytes of homosporous ferns

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Evidence for Oriented Adsorption in the Monolayers of Glassy Silica Gel & Fibrous Silica Gel (Santocel C)

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SKILL ACQUISITION FOR ENHANCING EMPLOYABILITY THROUGH MULTIPLE LEARNING EXPERIENCE INSTRUCTIONAL STRATEGY (MLEIS) – TOWARDS ENSURING INCLUSIVE AND EQUITABLE TECHNOLOGY EDUCATION

Matching skills to jobs has long been one of the important goals of education. The National Employability Report (2016) has highlighted the fact that engineering graduates do not fulfill the basic criteria of employability. It has been reported the current strategies do not address multiple modes and levels of numeracy, programming, computer literacy, algorithm and programming. It was revealed that students find certain subjects quite difficult and the objective based achievement test revealed failure to realize learning objectives and learning outcomes. Theory based instructional strategies and lecture mode of instructional delivery has been found to be not suited for engineering education [1]. In this study, the effectiveness of a Multiple Learning Experience based Instructional strategy (MLEIS) is explored. MLEIS is based on theories of learning, instruction design, learning styles and techno pedagogies. MLEIS envisages a skill based curricular strategy which addresses diversity, inclusiveness focusing on aspects like skill development, skill acquisition, professional competency and subject comprehension.  Article visualizations

Phasor Imaging: A Generalization of Correlation-Based Time-of-Flight Imaging

In correlation-based time-of-flight (C-ToF) imaging systems, light sources with temporally varying intensities illuminate the scene. Due to global illumination, the temporally varying radiance received at the sensor is a combination of light received along multiple paths. Recovering scene properties (e.g., scene depths) from the received radiance requires separating these contributions, which is challenging due to the complexity of global illumination and the additional temporal dimension of the radiance. We propose phasor imaging, a framework for performing fast inverse light transport analysis using C-ToF sensors. Phasor imaging is based on the idea that by representing light transport quantities as phasors and light transport events as phasor transformations, light transport analysis can be simplified in the temporal frequency domain. We study the effect of temporal illumination frequencies on light transport, and show that for a broad range of scenes, global radiance (multi-path interference) vanishes for frequencies higher than a scene-dependent threshold. We use this observation for developing two novel scene recovery techniques. First, we present Micro ToF imaging, a ToF based shape recovery technique that is robust to errors due to global illumination. Second, we present a technique for separating the direct and global components of radiance. Both techniques require capturing as few as 3−4 images and minimal computations. We demonstrate the validity of the presented techniques via simulations and experiments performed with our hardware prototype

The gametophyte of acrostichum aureum L.

The spores of A. aureum are trilete and granulose. On germination, a 6-10 cells long germ filament is produced, in which growth is mainly by intercalary formation of new cells rather than by cell elongation. One or two of the terminal cells become quiescent soon, and the intercalary cells form a prothallial plate. Cells on one side of the plate are more active than those on the other, and a broad ameristic lateral lobe is developed by their activity. As the lobe becomes spatulate, a multicellular meristem is differentiated from marginal cells on the side facing the posterior end of the germ filament. By the activity of the meristem the prothallus becomes cordate, with the meristem at the bottom of the notch. A midrib is formed behind the notch and the prothallus grows to become asymmetrically cordate. The mature prothallus is naked and with ruffled wings. Juvenile leaves possess entire, naked lamina

Biomimetic synthesis of hybrid nanocomposite scaffolds by freeze-thawing and freeze-drying

The aim of this study is to biomimetically synthesize hydroxyapatite - hydrophilic polymer scaffolds for biomedical applications. This organic-inorganic hybrid has been structurally characterized and reveals a good microstructural control as seen by the SEM analysis and the nanosize of the particulates is confirmed by AFM microscopy. The characterization of such nano-structured composites would allow researchers to design new systems, tailoring properties for different applications. © Indian Academy of Sciences

The prothallus of Polystichum

In the 9 spp. of Polystichum studied, a uniseriate germ filament is produced on spore germination. The anterior cells of the germ filament develop into a prothallial plate commonly before or sometimes after the terminal cell develops a papillate hair. A meristematic cell is differentiated early during plate formation, commonly in one of the daughter cells of the terminal cell or rarely (when the terminal cell is quiescent and hair-bearing as in P. aculeatum and P. lentum) of the penultimate cell. Young thalli become cordate in c. 8 weeks from spore germination and fully grown inc. 3 months. The mature prothallus is profusely hairy and cordate with a thick midrib and spread-out wings. Hairs are of the capped, unicellular, papillate type; a few club-shaped, unicellular hairs devoid of terminal caps are found in addition on the anterior margin. Sex organs are of the usual leptosporangiate type. The antheridium dehisces by a pore-like opening formed in the cap cell