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The significance of dust particles for the electron energy probability function (EEPF) and plasma oscillations is studied under varying magnetic field strength in a filamentary discharge hydrogen plasma. The experimental result shows that with an increase in dust density, the electron density decreases as a result of the charging of dust grains in the plasma background. A bi-Maxwellian EEPF is computed in both a pristine hydrogen plasma and a dust-containing plasma at different magnetic field strengths. We have observed that the increase in magnetic field decreases the lower energy electron population. The electron population of the lower energy range shows nearly identical results at magnetic field,
mT whereas the behaviour of the high-energy electron population becomes identical for a field strength
mT. From the observation, we have seen that the mid energy electron population slightly decreases and the high energy electron population slightly increases due to the presence of dust particles as compared to a pristine plasma. Further, very low energy electron population remains almost unchanged. With increase in dust density, the mid energy electron population further decreases whereas the high energy electron population slightly increases for different magnetic fields. But, no changes were observed for the very low energy electron population in the presence of dust particles. From the study of plasma oscillation, it is observed that the dominant frequency associated with the plasma oscillation is matched with the ion cyclotron frequency. The amplitude of the ion cyclotron frequency reduces with the increase of dust density which might be due to the decrease of plasma density.
We present early results from the first near-IR imaging of the weak X-ray sources discovered in the recent Chandra/ACIS-I survey towards the Galactic Centre (GC) (Wang et al. 2002). These ~800 discrete sources, which contribute significantly to the GC X-ray emission, represent an important and previously unknown population within the Galaxy. From our VLT observations we will identify likely IR counterparts to a sample of the hardest sources, which are most likely X-ray binaries. With these data we can place constraints on the nature of the discrete weak X-ray source population of the GC. Once the data analysis is complete we will discuss our results in the context of binary population synthesis models.
Two-dimensional (2D) materials are very promising with respect to their integration into optoelectronic devices. Monolayer tungsten diselenide (WSe2) is a direct-gap semiconductor with a bandgap of ∼1.6eV, and is therefore a complement to other two-dimensional materials such as graphene, a gapless semimetal, and boron nitride, an insulator. The direct bandgap distinguishes monolayer WSe2 from its bulk and bilayer counterparts, which are both indirect gap materials with smaller bandgaps. This sizable direct bandgap in a two-dimensional layered material enables a host of new optical and electronic devices. In this work, a comprehensive analysis of the effect of optical excitation on the transport properties in few-layer WSe2 is studied. Monolayer WSe2 flakes from natural WSe2 crystals were transferred onto Si/SiO2 (270nm) substrates by mechanical exfoliation. The flakes were observed under an optical microscope. A FET based on mechanically exfoliated WSe2 was fabricated using photolithography with Molybdenum as metal contact and Silicon as back gate and the electronic properties were measured in a wide range of temperatures. The mobility of our device was found to be 0.2 cm /V-S at room temperature. The schottky barrier height was found to decrease from 80 meV to 25 meV as the gate voltage increases.
In search of a suitable resource conservation technology under pigeonpea (Cajanus cajan L.)–wheat (Triticum aestivum L.) system in the Indo-Gangetic Plains, the effects of conservation agriculture (CA) on crop productivity and water-use efficiency (WUE) were evaluated during a 3-year study. The treatments were: conventional tillage (CT), zero tillage (ZT) with planting on permanent narrow beds (PNB), PNB with residue (PNB + R), ZT with planting on permanent broad beds (PBB) and PBB + R. The PBB + R plots had higher pigeonpea grain yield than the CT plots in all 3 years. However, wheat grain yields under all plots were similar in all years except for PBB + R plots in the second year, which had higher wheat yield than CT plots. The contrast analysis showed that pigeonpea grain yield of CA plots was significantly higher than CT plots in the first year. However, both pigeonpea and wheat grain yields during the last 2 years under CA and CT plots were similar. The PBB + R plots had higher system WUE than the CT plots in the second and third years. Plots under CA had significantly higher WUE and significantly lower water use than CT plots in these years. The PBB + R plots had higher WUE than PNB + R and PNB plots. Also, the PBB plots had higher WUE than PNB in the second and third years, despite similar water use. The interactions of bed width and residue management for all parameters in the second and third years were not significant. Those positive impacts under PBB + R plots over CT plots were perceived to be due to no tillage and significantly higher amount of estimated residue retention. Thus, both PBB and PBB + R technologies would be very useful under a pigeonpea–wheat cropping system in this region.
The authorship of the name Bauhinia diphylla (Fabaceae: Caesalpinioideae) has to be attributed to Banks instead of Buchanan-Hamilton. A lectotype is designated here for Bauhinia diphylla Banks [= Lysiphyllum diphyllum (Banks) de Wit].
This study presents the incidence of denture impaction in the oesophagus, and discusses the difficulties of managing such cases.
A total of 262 patients with a history of foreign body ingestion (between 1999 and 2010) were reviewed; 46 of these patients had dentures impacted in the oesophagus.
The cervical section of the oesophagus was the commonest site of impaction. Dysphagia and tracheal tenderness were the most consistent features when dentures became impacted in the upper oesophagus. In most cases, rigid oesophagoscopy enabled successful removal of the impacted denture. Locating an impacted denture hidden within the oesophageal mucosal folds sometimes proved difficult.
In cases of impacted dentures in the oesophagus, a positive history helps in the diagnosis, but a high degree of clinical suspicion aids early detection. Conventional radiographs are important but may not always be of assistance. Early intervention reduces complications. Dentures that are poorly maintained and old are more likely to be swallowed accidentally. The inclusion of radiopaque filler within dentures would assist localisation following accidental swallowing.
Rhinosporidiosis primarily affects the mucous membranes of the nose and nasopharynx. The disseminated form of this chronic fungal disease is extremely rare.
The authors present a case of disseminated rhinosporidiosis in an immunocompetent patient with involvement of the skin, subcutaneous tissue, muscle, bone, penis and urethra, and with a long-standing primary lesion in the nose.
A late or atypical presentation of rhinosporidiosis may cause diagnostic dilemma. Fine needle aspiration cytology of the tumoural lesions may establish the diagnosis. Histopathology is confirmatory. The subcutaneous masses may be solid or cystic. Ulceroproliferative lesions need to be differentiated from malignancies.
This is the first reported case of truly disseminated rhinosporidiosis with simultaneous involvement of multiple anatomically unrelated sites in a single patient. This is also the first reported case of cystic rhinosporidiosis. The possibility and sequelae of spontaneous regression of rhinosporidiosis are also discussed.
Unusually large transverse magnetic component has been observed at energy corresponding to the edge of heavy hole band in the optical emission from unstrained and strained layer single quantum well lasers above threshold condition. The existing model of Fermi sea shake-up is inadequate to explain the enhancement in the TM component beyond lasing threshold. Our results indicate that under lasing conditions the directional properties of the emitting dipole arising from electronic transitions to the heavy hole band is modified such that the dipole moment has equal projections in x, y and z directions.
Results on characterisation of undoped, μc-Si:H films prepared by rf magnetron sputtering technique are presented. Highly conducting films (10−3 Δ−cm−1) were obtained at fairly low rf power density (l.2W/cm2). Critical parameters for obtaining microcrystalline phase were identified. The effect of humid ambient on film properties was looked into.
Biomaterials have made significant contributions to the advancement of modern health care and drug delivery industries. The present research is based on development of porous polymerceramic composite scaffolds using polypropylene (PP) polymer and tricalcium phosphate (TCP) ceramic for bone-graft applications. Three dimensionally interconnected controlled porosity scaffolds were fabricated using a fused deposition modeling (FDM) system. First, ceramic and polymeric materials were compounded under high shear using a torque rheometer. Compounded materials were then extruded to a 1.78mm diameter continuous filament using a single screw extruder. These filaments were used as a feedstock material for an FDM 1650 machine for direct fabrication of controlled porosity parts. Hg-porosimetry was done to determine pore size and their distribution in these structures. Tensile properties of neat composites and as received polymer were measured and compared using standard dog bone samples. Uniaxial compression tests were performed on cylindrical porous samples having average pore size of 160 μm and 36 vol% porosity. These samples showed an average ultimate compressive strength of 12.7 MPa. Average compressive modulus was calculated as 263 MPa. Cytotoxicity and cell proliferation studies were conducted with OPC1 modified human osteoblast cell-line. It was found that composite matrices were non-toxic and they showed excellent cell growth with OPC1 cells.
We have measured the ensemble averaged transverse spin relaxation time T2* (associated with g = 4 resonance) in bulk powders of the organic molecule Alq3, and in samples containing 1-2 molecules confined in nanocavities of dimension ˜ 2 nm. Both T2* times are strongly temperature dependent indicating that they are determined by phonon-mediated spin relaxation. Interestingly, the T2* time in nanocavities is ˜2.5 times longer than in bulk powder over a wide temperature range. The longer T2* in the nanocavity is evidence of weakened electron-phonon interaction. We believe that electron-phonon interaction is suppressed because the cavity confines phonons and discretizes the phonon modes and phonon energies. As a result, the chances of a phonon induced (inelastic) spin relaxation event are reduced owing to the need to conserve energy in the relaxation process. This is a novel “phonon bottleneck effect” that to our knowledge has not been previously reported.
The present study describes the activity of a nanomaterial on protoscoleces of Echinococcus granulosus, which exhibited morphological changes and apoptosis. Apoptotic changes were deduced on the basis of effector caspase activation and nucleosomal laddering. Invaginated protoscoleces maintained in vitro became evaginated and had hooks, presumptive suckers and stalks. Degenerative changes of protoscoleces were evidenced after treatment with praziquantel and nano-combination. Protoscoleces treated with praziquantel had distinct attestation of necrosis and nano-combination-treated protoscoleces had signatures of apoptosis.
Port Blair, the capital city of the Union Territory of Andaman and Nicobar Islands in the republic of India, witnessed an outbreak of chikungunya (CHIK) fever in 2006. Although no deaths attributable to CHIK fever were registered, thousands of people were affected. In view of evidence from other parts of the world indicating that CHIK fever does cause death we studied the mortality trend in Port Blair from 2002 to 2008 in order to verify if there was increased mortality during the CHIK fever epidemic. The expected number of monthly deaths in 2006 was calculated by multiplying the average monthly mortality rate from 2002 to 2008 (with the exception of 2006) with the monthly population in 2006. The results indicated that there was a significant increase in expected deaths during some months of 2006, which coincided with the peak in the CHIK fever epidemic in Port Blair.
This study evaluated the existence of different genotypes of Haemonchus contortus prevailing among goats in West Bengal, India. These parasites were isolated from the abomasum of goat intestine and the molecular characterization was performed by comparing variation of nucleotide sequences of the internal transcribed spacer 1 (ITS-1) gene region. Single-strand conformation polymorphism (SSCP) analysis of ITS-1 amplified product showed the presence of three distinct conformations both in male and female parasites. The sequence analysis of conformations showed two single nucleotide polymorphisms (SNP) in male parasites at nucleotide positions 106 and 107 and one SNP was detected in female parasites at nucleotide position 157. These nucleotide variations in different isolates did not alter the interior loop structure of the predicted secondary RNA, therefore we believe these variations may not be responsible for any evolutionary changes among conformations.
Cystic echinococcosis (CE) caused by the larval stage of Echinococcus granulosus is a disease that affects both humans and animals. In humans the disease is treated by surgery with a supplementary option of chemotherapy with a benzimidazole compound. During the present study heat-shock protein 60 (HSP 60) was identified as one of the most frequently expressed biomolecules by E. granulosus after albendazole treatment. Data were correlated with 14-3-3 protein signature, and overexpression of this molecule after albendazole induction was an indicator of cell survival and signal transduction during in vitro maintenance of E. granulosus for up to 72 h. This observation was further correlated with a uniform expression pattern of a housekeeping gene (actin II). Out of three β-tubulin gene isoforms of E. granulosus, β-tubulin gene isoform 2 showed a conserved point mutation indicative of benzimidazole resistance.
We survey the environment of Cl 1806-20 using near-infrared narrow-band imaging to search for Brγ features indicative of evolved massive stars. Using this technique, we successfully detect previously identified massive stars in the cluster. We detect no new emission line stars, establishing a firm upper limit on the number of Wolf Rayets and Luminous Blue Variables; however, we do find several candidate OB supergiants, which likely represent the bulk of the heretofore undiscovered massive star population.
The metacestode stage of Echinococcus granulosus is of zoonotic importance. In general, the 14-3-3 protein is involved in multiplication and survival of eukaryotes. Therefore, this communication presents succinct information on relative expression of the 14-3-3 protein in six different morphotypes of cysts of E. granulosus. All isolated E. granulosus belonged to the common sheep strain (G1). Relative expression of the 14-3-3 protein was higher in fertile cysts when compared to sterile cysts. The predicted amino acid sequence of the 14-3-3 protein was closely clustered with zeta-type isoforms 1 and 2 of the 14-3-3 protein. In addition, the present study demonstrates the presence of the 14-3-3 protein which until now had not been detected in the germinal layer. Our findings indicate that the expression of this biomolecule in the germinal layer of sterile organisms may contribute to the development and survival of the parasite in the host. The uniform expression of actin II conclusively proves the survivability of the harvested organisms.