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Castor is a prime industrial crop belonging to a monotypic genus and its genetic improvement depends on creating desired variability in the primary gene pool. This study reports the development of tetraploid castor plants through colchicine treatment. Seeds of three castor genotypes were soaked in aqueous solutions of colchicine with variable concentrations, and the LD50 value was determined. Of 1010 treated field-raised plants, three were identified as potential polyploids based on increases in a guard cell size and reductions in the number of stomata. The putative polyploid plants were selfed and the progeny were subjected to meiotic analysis. All the progeny were found to be tetraploid. The pairing of chromosomes was abnormal with univalent to octavalent configurations during meiosis-I, but the later parts of meiosis were normal. Seasonal variations in pollen fertility indicated the possible role of temperature-sensitive male sterility in causing the sterility in tetraploid plants. The tetraploid plants were phenotypically comparable with their diploid counterparts, but produced substantially bigger seeds. Thus, these tetraploid plants are valuable resources for basic and applied research in castor.
This paper presents three different age domains, obtained by electron microprobe monazite dating, for granulitic gneisses collected from the Shillong-Meghalaya Gneissic Complex in Sonapahar, NE India, which contain radioactive materials, e.g. thorium (3.32–7.20 wt %), uranium (0.133–1.172 wt %) and lead (0.101–0.513 wt %). The microprobe analyses of monazite grains in the rock samples show that the monazites have three different ages ranging from Mesoproterozoic to Neoproterozoic. The oldest age (1571 ± 22 Ma) represents a peak metamorphic event, the youngest dominant age indicates the Pan-African tectonic event (478 ± 7 Ma) and the intermediate age marks the Grenvillian orogeny (1034 ± 91 Ma) or may be a mixing artefact; these ages are located at the cores, rims and intermediate parts of the monazite grains, respectively. The equilibrium mineral phases calculated for the granulitic gneisses from Sonapahar lie in a P–T range from 5.9 kbar/754 °C to 8.3 kbar/829 °C in the NCKFMASH system. Plotting the P–T conditions of the granulitic gneisses reveals a clockwise P–T path. Two major metamorphic events are observed in Sonapahar. The M1 metamorphic stage is represented by peak mineral assemblages of prograde garnet-forming reactions (8.2 kbar/∼713 °C) during Mesoproterozoic time (1571 ± 22 Ma). The M2 metamorphic stage featured decompression (3.9 kbar/∼701 °C) in which garnet–sillimanite broke down to form cordierite along an isothermal decompression path during the Pan-African tectonic event (478 ± 7 Ma).
Research on informed choice in modern contraceptive method acceptance by young married women is pertinent in the broader context of individual freedom and reproductive rights, especially in countries where women continue to have limited control over their reproductive and contraceptive choices. This study in India asked: (1) is young married women’s acceptance of specific modern contraceptive methods an informed choice? and (2) what are the enablers and barriers to informed choice? The study used data for currently married women aged 15–24 (N = 20,752) from the fourth round of the National Family Health Survey (NFHS-4) conducted in 2015–16. A Method Information Index (MII) was calculated as a measure of informed choice from the percentage of users who responded ‘yes’ to all three questions on: whether they were informed about methods other than the one they received, told about the method-specific side-effects, and advised what to do if they experienced side-effects. Binary logistic regression analysis was carried out to examine the adjusted effect of factors associated with the MII separately for female sterilization, the intrauterine device and the oral contraceptive pill, and a combined MII including all three methods plus injectables. One-fifth of the study women used any modern contraceptive method at the time of survey, of which only 36% had fully informed choice. The likelihood of being informed about the methods was significantly higher among those using the oral contraceptive pill (OR: 1.75, CI 1.58–1.94), IUD (OR: 2.23, CI 1.97–2.52) and injectables (OR: 1.37, CI 0.97–1.94) compared with those who were sterilized. Informed choice varied by region and the socioeconomic profile of the users. Inadequately informed choice violates the reproductive rights of young women and might result in higher post-use health problems, discontinuation of and unmet need for contraceptives, unintended pregnancies, induced abortions and regret, adversely affecting women’s health. Training of health/family planning workers in India about the importance of reproductive rights is urgently required to enhance informed contraceptive choice and improve the health of young married women.
Giant cell tumor (GCT) of bone is a common benign lesion that causes significant morbidity due to the failure of modern medical and surgical treatment. Surface ultra-structures of giant cells (GCs) may help in distinguishing aggressive tumors from indolent GC lesions. This study aimed to standardize scanning electron microscopic (SEM) imaging of GC from GCT of bone. Fresh GCT collected in Dulbecco's Modified Eagle Medium was washed to remove blood, homogenized, or treated with collagenase to isolate the GCs. Mechanically homogenized and collagenase-digested GCs were imaged on SEM after commonly used drying methodologies such as air-drying, tetramethylsilane (TMS)-drying, freeze-drying, and critical point-drying (CPD) for the optimization of sample processing. The collagenase-treated samples yielded a greater number of isolated GC and showed better surface morphology in comparison to mechanical homogenization. Air-drying was associated with marked cell shrinkage, and freeze-dried samples showed severe cell damage. TMS methodology partially preserved the cell contour and surface structures, although the cell shape was distorted. GC images with optimum surface morphology including membrane folding and microvesicular structures on the surface were observed only in collagenase-treated and critical point-dried samples. Collagenase digestion and critical point/TMS-drying should be performed for optimal SEM imaging of individual GCs.
We have performed photometric analysis of four Galactic globular clusters (GGCs): NGC 4147, NGC 4590, NGC 5053 and NGC 7492 using far-UV and near-UV filters of the Ultraviolet Imaging Telescope (UVIT) on-board AstroSat. With the help of color-magnitude diagrams (CMDs), we have identified ~150 blue horizontal branch stars (BHBs), and ~40 blue straggler stars (BSS) in the four GGCs. We study the temperature and radial distribution of BHBs and BSS for the four GGCs.
This paper presents a substrate-integrated waveguide (SIW) mixed electric and magnetic coupling structure implemented on a single-layer substrate to create finite transmission zeros (TZs), which can be used to design microwave filters with higher frequency selectivity. Mixed coupling is realized by three slot-lines on the top metal plane combined with an iris-window between two adjacent SIW cavities. The electric and magnetic coupling can be separately controlled by adjusting the dimensions of the slot-lines and the width of the iris-window, and a controllable TZ below or above the passband can be produced. Furthermore, a detailed analysis of the mixed coupling structure is presented. To demonstrate the validity of the proposed structure, third- and fourth-order cross-coupled generalized Chebyshev bandpass filters are designed and fabricated using the standard printed circuit board process. The experimental results are in good agreement with the simulation results. The filters exhibit simple structure and good frequency selectivity.
We consider a scale invariant Cassinian metric and a Gromov hyperbolic metric. We discuss a distortion property of the scale invariant Cassinian metric under Möbius maps of a punctured ball onto another punctured ball. We obtain a modulus of continuity of the identity map from a domain equipped with the scale invariant Cassinian metric (or the Gromov hyperbolic metric) onto the same domain equipped with the Euclidean metric. Finally, we establish the quasi-invariance properties of both metrics under quasiconformal maps.
This study aimed to evaluate the surgical success of a modified inlay tympanoplasty technique, known as circumferential subannular tympanoplasty, for anterior and subtotal perforations.
This prospective study was performed in a tertiary care teaching hospital between October 2013 and April 2016. A total of 58 adult patients of both sexes with anterior or subtotal perforations underwent circumferential subannular tympanoplasty under local anaesthesia. In this technique, after tympanomeatal flap elevation, the temporalis fascia graft is placed directly onto the annulus instead of being tucked underneath the tympanic membrane remnant. Outcome data were graft uptake and hearing improvement.
This technique had a surgical success rate of 97 per cent and led to significant hearing improvement.
Circumferential subannular tympanoplasty has a definitive role in managing anterior and subtotal perforations.
A probe feed wideband multi-element dual segments quarter cylindrical dielectric resonator antenna (q-CDRA) in composite forms have been proposed. The q-CDRA has been introduced by splitting CDRA into four uniform quarters and multi-segmentation approach has been castoff for further improvement in bandwidth of q-CDRA. The dual segments q-CDRA has been designed and analyzed using theoretical analysis and Ansoft HFSS simulation software. Further the dual segment multi-element q-CDRAs in composite form have been designed. A coaxial probe has been placed at the center of the ground plane for the excitation of proposed multi-element and multi-segmented composite form of q-CDRA, which excite TM01δ mode in the proposed antenna. The input characteristics and radiation patterns of the proposed composite antennas have been studied and their results are compared with corresponding experimental results. Prototype of single, two, and four elements dual-segment composite q-CDRAs have been fabricated and input characteristics of the proposed composite antennas have been compared with each other. Four elements dual-segment composite q-CDRA has shown wide impedance bandwidth (|S11| ≤ −10 dB) of 85.13% with monopole-like radiation pattern. The peak gain of 4.85 dBi with 98.5% radiation efficiency has been achieved for dual-segment four elements composite q-CDRA. The proposed multi-element dual-segment composite q-CDRAs may find suitable applications in C and X-band with complete covering of the 5.0 GHZ wireless local area network (WLAN) and worldwide interoperability for microwave access (WiMAX) band.
A novel quarter cylindrical dielectric resonator antenna (q-CDRA) has been introduced by splitting four uniform quarters from a cylinder. q-CDRA has been designed and validated with theoretical analysis. Two and four element q-CDRAs have been proposed in composite forms through Ansoft high-frequency structure simulator simulation software and fabricated for experimental investigation. The input characteristics and radiation patterns of the proposed antennas have been studied through simulation and compared with the measured ones. The |S11| characteristics of the proposed antennas have been compared with each other. The four-element composite q-CDRA has wide impedance bandwidth (|S11| ≤ −10 dB) of 58.15% with monopole-like radiation pattern as compared with other q-CDRAs. The two and four elements q-CDRAs have symmetric monopole-like radiation patterns with linear polarization for whole operating bandwidth (4.5–8.6 GHz). The proposed composite q-CDRAs may find suitable applications in WLAN and WiMAX band.
In this paper, a wideband two-segmented four-element triangular dielectric resonator antenna (TDRA) with coaxial probe feed has been proposed. The proposed antenna has been analyzed, optimized, and studied through Ansoft HFSS simulation software. The prototype of the proposed antenna has been fabricated and its input characteristics are measured with the help of R&S Vector Network Analyzer. Good agreement has been obtained between simulated and measured results. The proposed design has been compared with two segments TDRA and found wider bandwidth with lower resonant frequency. The proposed antenna provides monopole-like radiation pattern over the entire bandwidth with nearly 33% bandwidth (return loss ≥10 dB) at a resonant frequency 6.9 GHz and 4.93 dBi peak gain. The proposed antenna is suitable for application of C-band microwave frequencies.
A wideband four element triangular dielectric resonator antenna (TDRA) has been designed and fabricated by using 50 Ω coaxial probe feed. The input and radiation characteristics of the proposed antenna have been extracted through Ansoft HFSS and CST Microwave Studio simulation software and compared with the experimental results. The simulated results have been in good agreement with the experimental results. The proposed antenna characteristics have also been compared with the same dimensions of the single element TDRA, and found enhancement in bandwidth with lower resonant frequency. Its performance has also been compared with same area (equal to proposed antenna) of single element TDRA. The proposed antenna provides nearly 37% bandwidth (|S11| < −10 dB) at a resonant frequency of 5.45 GHz with 4.76 dBi peak gain. The symmetry and uniformity in the radiation patterns is obtained consistently for the entire operating bandwidth. The proposed antenna shows consistently symmetric monopole type radiation pattern with low cross polarization for WLAN (IEEE 802.16) and WiMAX applications. The performance of the proposed antenna has been compared with some similar type of dielectric resonator antenna (DRA) shapes and it has been observed that TDRA is taking very less radiation area for giving better performance than other DRA shapes.
A single specimen of the African spadefish, Tripterodon orbis, was landed in a gill net operating off Visakhapatnam on 13 December 2013. The morphometric and meristic characters of the recorded specimen are described and discussed herein. This is the first occurrence of the species from the north-east coast of India, exhibiting an extension in distribution from the southern to the northern region, along the Bay of Bengal.
In this study, samples of dental porcelain bodies have been made by using the materials collected from selected deposits employing different mixing proportions of clay, quartz and feldspar. Dental porcelain ceramics have been successfully fabricated by using the sintering technique together with some Na2CO3 additive. The dental porcelain powder has been pressed into pellets at first and subsequently sintered at 700, 800, 900, 1000 and 1100 °C for 2 h. The physical and mechanical properties of the prepared samples have been investigated. The sintering behavior of the fired samples has been evaluated by bulk density, linear shrinkage, water absorption and apparent porosity measurements. This study includes the evaluation of the Vickers’s microhardness by microhardness tester. Phase analysis and microstructural study have been performed by XRD and optical microscope respectively. Optical properties have been investigated using UV-visible spectroscopy. Influence of firing conditions on leucite formation, densification and microstructural development of the sintered samples has been investigated. It has been found that the choice of sintering temperature is one of the key factors in controlling leucite crystallization in dental porcelain ceramics. It has also been found that the flux concentration of material and the effect of temperature on preparation of dental porcelain contribute to the firing shrinkage and hardness, which has been found to increase with the increase of treatment temperature.
Aberrant gene expression occurs in parthenogenetic embryos due to abnormal epigenetic modifications in the genome that probably diminish viability and enhance developmental abnormalities in these embryos. In the present study, five developmentally important genes (HPRT1, Cx43, Sox2, Mest and IGF2R) were analysed at different stages in parthenotes (haploid and diploid) and compared with similar stages in in vitro fertilized (IVF) embryos. The results indicated that in haploid parthenotes expression of HPRT1 was upregulated (P < 0.05) only at the 2–4-cell stage whereas Cx43 expression was significantly (P < 0.05) downregulated in all stages as compared with the control. However, expression of this gene was upregulated (P < 0.05) in 2–4-cell and morula stages of diploid parthenotes. Expression of Sox2 was significantly (P < 0.05) downregulated in morula stage haploid parthenotes, whereas it was upregulated (P < 0.05) in 8–16-cell stage diploid embryos. The expression of Mest was upregulated (P < 0.05) at the 2–4-cell stage of both haploid and diploid parthenotes, whereas it was downregulated in 8–16-cell stage diploid embryos as compared with control. IGF2R expression was upregulated (P < 0.05) only in morula stage haploid and diploid parthenote as compared with control. These results indicate that parthenogenetic embryos showed aberrant gene expression of developmentally important genes such as HPRT1, Cx43, Sox2, Mest and IGF2R in comparison with IVF embryos, this finding may be one of the major reasons for the poor developmental competence of parthenogenetic embryos.
Cyanobacteria represent promising organic inputs in rice–wheat cropping system, as they contribute towards accretion of N and C, besides secreting growth-promoting substances which influence plant productivity and soil fertility. The present study focused towards using a combinatorial approach for evaluating field-level colonization of cyanobacteria in soil and their effect on soil microbiological and plant parameters, employing agronomic and molecular tools. A consortium of cyanobacterial strains (BF1, Anabaena sp., BF2, Nostoc sp., BF3, Nostoc sp. and BF4, Anabaena sp.) was employed in different three-and four-member combinations along with 75% N + Full dose of P and K fertilizers. A significant enhancement in microbial activity and plant growth/yields and savings of 25% N in the wheat–rice cropping sequence were recorded, especially in treatments involving 75% N + Full dose of PK+BF1+BF2+BF4 and T5, i.e. 75% N + Full dose of PK+BF1+BF2+BF3. Such treatments were significantly higher or statistically at par with fertilizer controls – 75% N + Full dose of PK fertilizers. The use of DNA-based markers further helped to establish the colonization of the inoculated cyanobacteria, especially BF2 and BF3 strains. Our study clearly illustrated the establishment of inoculated cyanobacterial strains and their role in enhancing the crop productivity and soil health of the rice–wheat cropping system.
In this paper, the low-Reynolds number (Re = 80) flow around a row of nine square cylinders placed normal to the oncoming flow is investigated using the lattice-Boltzmann method. The effects of the cylinder spacing on the flow are studied for spacing to diameter ratios of 0.3 to 12. No significant interaction between the wakes is observed with spacings greater than six times the diameter. At smaller spacings, the flow regimes as revealed by vorticity field and drag coefficient signal are: synchronized, quasi-periodic and chaotic. These regimes are shown to result from the interaction between primary (vortex shedding) and secondary (cylinder interaction) frequencies; the strength of the latter frequency in turn depends on the cylinder spacing. The secondary frequency is also related to transition between narrow and wide wakes behind a cylinder.
The mean drag coefficient and Strouhal number are found to increase rapidly with a decrease in spacing; correlations of these parameters with spacing are proposed. The Strouhal number based on gap velocity becomes approximately constant for a large range of spacings, highlighting the significance of gap velocity for this class of flows. It is also possible to analyse the vortex pattern in the synchronized and quasi-periodic regimes with the help of vorticity dynamics. These results, most of which have been obtained for the first time, are of fundamental significance.
Brinjal (Solanum melongena L.) is an important solanaceous vegetable in many countries of Asia and Africa. It is a good source of minerals and vitamins in the tropical diets. Assessment of genetic resources is the starting point of any crop improvement programme. In India, the National Bureau of Plant Genetic Resources is the nodal institute for management of germplasm resources of crop plants and holds more than 2500 accessions of brinjal in its genebank. In the present study, morphological diversity in a set of 622 accessions, comprising 543 accessions from indigenous sources and 79 accessions of exotic origin, was assessed. Wide range of variations for 31 descriptors, 13 quantitative and 18 qualitative, were recorded. The wide regional variations for plant, flower and fruit descriptors revealed enough scope for improvement of yield characters by selection. The genetic differences among the landraces are potentially relevant to breeding programmes in that the variability created through hybridization of the contrasting forms could be exploited.