188 research outputs found
Influence of Ethylene Inhibitors and Ethrel on Production of Protocorm Like Bodies in Orchid-Dendrobium 'Sonia'
To increase the efficiency of production of protocorm like bodies, ethylene inhibitors like silver nitrate, salicylic acid and cobalt chloride at three concentrations, viz., 2, 5 and 20 μM and ethrel at 0.7, 1.4 and 14.0 μM were tested, by supplementing MS basal with BAP 4.44 μM. The explant used was fractionated protocorm like bodies (plb). Ethylene and methane gases evolved by the explant in the culture container were measured at 20 and 40 days after inoculation (DAI). Among various ethylene inhibitors tested, the maximum number of plb's were produced in media containing silver nitrate (5 μM), cobalt chloride (2 μM) and salicylic acid (20 μM). All ethrel treatments produced succulent, vitrified and deformed plb's. No ethylene evolution was observed in any of the ethylene inhibitor treatments. Only in ethrel treatments was evolution of ethylene observed. Methane evolution was observed in all the ethylene inhibitor treatments. Absolute amounts of methane evolved could not be related to the observed plb production. However, when the evolution of methane was more than 1 nano mole g-1 FW h-1, poor plb production was observed
An approach for selecting text from e-mail in satellite-based education
It was in September 2004 that Indian Space Research Organization(ISRO), in its endeavor
to provide sustainable distance education service in India, launched EDUSAT that is designed to supplement the present teaching system in the country.The EDUSAT project has sought to wipe out disparities in quality
between the various educational institut
ions by addressing itself to key issues of access, interactivity, cost-effectiveness and consistency of information to students.One subject expert can simultaneously teach
hundreds of students in multiple locations across a vast geographical area.The major issue of paucity of faculty members in higher education has been tackled in one single stroke. In this regard, VTU has set up a
Forum(http://forum.vtu.ac.in), which provides a platform for students to exchange their view, share resources and also get answers from subject experts by sending their queries into this Forum by e-mail.As this VTU-EDUSAT
network is being used by a whopping 150,000 students, there will be thousands of questions
from students across different subjects that will be handled through the network by hundreds of subject experts.The questions will be aired by the students during the live sessions of the satellite-based programme or by sending e-mail post transmission of sessions.Further, there will be number of questions by the students after they go through the e-Learning content.It has become impossible to answer all these questions by the subject experts because of paucity of time.It is also observed that there will be many questions that are similar or repetitive or these questions would have been answered earlier by the subject experts.Also, it is impossible for the subject expert to go through all the e-mails completely.Therefore, it is required to develop a solution that involves summarization of e-mail text sent by the students, which means selection of important sentences or text so as to compare them with the current database of questions. Once comparison is made, only the non- repetitive questions are extracted and place them before the subject expert. Further, if the answer is already available for questions, the system advices students to refer the FAQ data base.Here, it is necessary to distinguish the important information with less important information within the original text (e-mail).For this, we need the
combination of two steps: information filtering and text reduction.The on-going research is to address such an issue by domain-specific text summarization. We have
made an attempt to develop a model that examines content-based text selection
A comparative evaluation : oral leukoplakia surgical management using diode laser, CO2 laser, and cryosurgery
The comparatively evaluate the three surgical treatment modalities namely cryosurgery, diode and CO2 laser surgery in terms of healing outcomes on the day of surgery, first and second week post operatively and recurrence at the end of 18 months was assessed. Thirty selected patients were divided randomly into three groups. Each group comprising of ten patients were subjected to one of the three modalities of treatment namely cryosurgery, diode laser or CO2 laser surgery for ablation of OL. Obtained data was analyzed using mainly using Chi-square and Anova tests. Study showed statistical significant differences (p > 0.05) for evaluation parameters like pain, edema and scar. The parameters like infection, recurrence, bleeding showed no statistical significance. Pain was significantly higher in CO2 laser surgery group as compared with diode laser group. There was no recurrence observed at the end of the 6 months follow up period in all the three study groups. Observations from the study highlights that all three surgical modalities used in this study were effective for treatment of OL, and the overall summation of the results of the study showed that laser therapy (CO2 and Diode) seems to offer better clinically significant results than cryotherapy
Laser Writing of Semiconductor Nanoparticles and Quantum Dots
Silica aerogels were patterned with CdS using a photolithographic technique based on local heating with infrared (IR) light. The solvent of silica hydrogels was exchanged with an aqueous solution of the precursors CdNO3 and NH4 OH, all precooled to a temperature of 5°C. Half of the bathing solution was then replaced by a thiourea solution. After thiourea diffused into the hydrogels, the samples were exposed to a focused IR beam from a continuous wave, Nd-YAG laser. The precursors reacted in the spots heated by the IR beam to form CdS nanoparticles. We lithographed features with a diameter of about 40 µm, which extended inside the monoliths for up to 4 mm. Samples were characterized with transmission electron microscopy and optical absorption, photoluminescence, and Raman spectroscopies. Spots illuminated by the IR beam were made up by CdS nanoparticles dispersed in a silica matrix. The CdS nanoparticles had a diameter in the 4-6 nm range in samples exposed for 4 min to the IR beam, and of up to 100 nm in samples exposed for 10 min
Bundling up carbon nanotubes through Wigner defects
We show, using ab initio total energy density functional theory, that the
so-called Wigner defects, an interstitial carbon atom right besides a vacancy,
which are present in irradiated graphite can also exist in bundles of carbon
nanotubes. Due to the geometrical structure of a nanotube, however, this defect
has a rather low formation energy, lower than the vacancy itself, suggesting
that it may be one of the most important defects that are created after
electron or ion irradiation. Moreover, they form a strong link between the
nanotubes in bundles, increasing their shear modulus by a sizeable amount,
clearly indicating its importance for the mechanical properties of nanotube
bundles.Comment: 5 pages and 4 figure
PI3K p110δ uniquely promotes gain-of-function Shp2-induced GM-CSF hypersensitivity in a model of JMML
Although hyperactivation of the Ras-Erk signaling pathway is known to underlie the pathogenesis of juvenile myelomonocytic leukemia (JMML), a fatal childhood disease, the PI3K-Akt signaling pathway is also dysregulated in this disease. Using genetic models, we demonstrate that inactivation of phosphatidylinositol-3-kinase (PI3K) catalytic subunit p110δ, but not PI3K p110α, corrects gain-of-function (GOF) Shp2-induced granulocyte macrophage-colony-stimulating factor (GM-CSF) hypersensitivity, Akt and Erk hyperactivation, and skewed hematopoietic progenitor distribution. Likewise, potent p110δ-specific inhibitors curtail the proliferation of GOF Shp2-expressing hematopoietic cells and cooperate with mitogen-activated or extracellular signal-regulated protein kinase kinase (MEK) inhibition to reduce proliferation further and maximally block Erk and Akt activation. Furthermore, the PI3K p110δ-specific inhibitor, idelalisib, also demonstrates activity against primary leukemia cells from individuals with JMML. These findings suggest that selective inhibition of the PI3K catalytic subunit p110δ could provide an innovative approach for treatment of JMML, with the potential for limiting toxicity resulting from the hematopoietic-restricted expression of p110δ
Osjetljiva spektrofotometrijska metoda za određivanje sulfonamida u farmaceutskim pripravcima
A new, simple and sensitive spectrophotometric method for the determination of some sulfonamide drugs has been developed. The method is based on the diazotisation of sulfacetamide, sulfadiazine, sulfaguanidine, sulfamerazine, sulfamethazine, sulfamethoxazole and coupling with 8-hydroxyquinoline in alkaline media to yield red coloured products, with absorption maximum at 500 nm. The Beer’s law is obeyed from 0.17.0 µg mL1. The limits of quantification and limits of detection were 0.110.18 and 0.030.5 µg mL1, respectively. Intraday precision (RSD 0.10.5%) and accuracy (recovery 97.3100.8) of the developed method were evaluated. No interference was observed from common adjuvants. The method has been successfully applied to the assay of sulpha drug in the pharmaceutical formulations.U radu je opisana nova, jednostavna i osjetljiva spektrofotometrijska metoda za određivanje sulfonamida. Metoda se temelji na prevođenju sulfacetamida, sulfadiazina, sulfagvanidina, sulfamerazina, sulfometazina i sulfametoksazola u diazoderivate koji kondenzacijom s 8-hidroksikinolinom u alkalnom mediju daju crveno obojene produkte s maksimumom apsorpcije pri 500 nm. Beerov zakon vrijedi u koncentracijskom rasponu 0,17,0 µg mL1. Granice kvantifikacije i granice detekcije su 0,11-0,18, odnosno 0,03-0,05 µg mL-1. Za predloženu metodu procijenjene su intermedirska preciznost (RSD 0.1-0,5%) i točnost (analitički povrat 97,3-100,8). Uobičanjene pomoćne tvari u tabletama ne interferiraju tijekom određivanja. Metoda je uspješno primijenjena za analizu sulfonamida u farmaceutskim pripravcima
Analysis of cardiac signals using spatial filling index and time-frequency domain
BACKGROUND: Analysis of heart rate variation (HRV) has become a popular noninvasive tool for assessing the activities of the autonomic nervous system (ANS). HRV analysis is based on the concept that fast fluctuations may specifically reflect changes of sympathetic and vagal activity. It shows that the structure generating the signal is not simply linear, but also involves nonlinear contributions. These signals are essentially non-stationary; may contain indicators of current disease, or even warnings about impending diseases. The indicators may be present at all times or may occur at random in the time scale. However, to study and pinpoint abnormalities in voluminous data collected over several hours is strenuous and time consuming. METHODS: This paper presents the spatial filling index and time-frequency analysis of heart rate variability signal for disease identification. Renyi's entropy is evaluated for the signal in the Wigner-Ville and Continuous Wavelet Transformation (CWT) domain. RESULTS: This Renyi's entropy gives lower 'p' value for scalogram than Wigner-Ville distribution and also, the contours of scalogram visually show the features of the diseases. And in the time-frequency analysis, the Renyi's entropy gives better result for scalogram than the Wigner-Ville distribution. CONCLUSION: Spatial filling index and Renyi's entropy has distinct regions for various diseases with an accuracy of more than 95%
Molecular Cloning and Expression Analysis of fushi tarazu Factor 1 in the Brain of Air-Breathing Catfish, Clarias gariepinus
BACKGROUND: Fushi tarazu factor 1 (FTZ-F1) encodes an orphan nuclear receptor belonging to the nuclear receptor family 5A (NR5A) which includes adrenal 4-binding protein or steroidogenic factor-1 (Ad4BP/SF-1) and liver receptor homologue 1 (LRH-1) and plays a pivotal role in the regulation of aromatases. METHODOLOGY/PRINCIPAL FINDINGS: Present study was aimed to understand the importance of FTZ-F1 in relation to brain aromatase (cyp19a1b) during development, recrudescence and after human chorionic gonadotropin (hCG) induction. Initially, we cloned FTZ-F1 from the brain of air-breathing catfish, Clarias gariepinus through degenerate primer RT-PCR and RACE. Its sequence analysis revealed high homology with other NR5A1 group members Ad4BP/SF-1 and LRH-1, and also analogous to the spatial expression pattern of the latter. In order to draw functional correlation of cyp19a1b and FTZ-F1, we analyzed the expression pattern of the latter in brain during gonadal ontogeny, which revealed early expression during gonadal differentiation. The tissue distribution both at transcript and protein levels revealed its prominent expression in brain along with liver, kidney and testis. The expression pattern of brain FTZ-F1 during reproductive cycle and after hCG induction, in vivo was analogous to that of cyp19a1b shown in our earlier study indicating its involvement in recrudescence. CONCLUSIONS/SIGNIFICANCE: Based on our previous results on cyp19a1b and the present data, it is plausible to implicate potential roles for brain FTZ-F1 in ovarian differentiation and recrudescence process probably through regulation of cyp19a1b in teleosts. Nevertheless, these interactions would require primary coordinated response from ovarian aromatase and its related transcription factors
Sex determination in annual fishes: searching for the master sex-determining gene in Austrolebias charrua (Cyprinodontiformes, Rivulidae)
- …