396 research outputs found
Paclitaxel delivery by micro/nano encapsulation using layer-by-layer assembly
A novel formulation of paclitaxel (PTX) has been developed by providing multilayer assembly over drug loaded porous CaCO3 microparticles (CaCO3 MP) using combination of biocompatible and biodegradable polyelectrolytes (PE’s). PTX was encapsulated into the nanopores of preformed CaCO3 MP prepared by the co-precipitation method. Infrared (IR) and X-ray diffraction (XRD) provides evidences that PTX has been encapsulated into nanopores of CaCO3 MP and not crystallized on the surface. PTX loaded CaCO3 MP (CaCO3-PTX) was found to be highly stabilized against thermal decomposition as evinced by thermo gravimetric analysis (TGA) indicating decomposition at 600°C and 250°C for CaCO3-PTX and PTX respectively. The multilayer assembly over CaCO3-PTX was effectuated by alternate deposition of protamine sulfate (PRM) and sodium alginate (SA) using LBL technique followed by subsequent core removal [PTX- (PRM/SA)5]. The pay load efficiency of PTX in this system was found to be 78.98±2.14%. The developed system was further evaluated for surface morphology, size and size distribution, surface charge, core removal and layer-by-layer growth due to sequential adsorption of PE’s. The release data of PTX-(PRM/SA)5 was comparable with marketed formulation of PTX (PTX-M) and CaCO3-PTX when performed in simulated intestinal fluid (SIF pH=7.4). The release profile of PTX-(PRM/SA)5 indicates that PEs based multilayer matrix is capable to provide barrier to PTX release as it has been found to follow first order matrix diffusion kinetics with 64±4.8% release within 24 hrs. The t50% of PTX-M, CaCO3-PTX and PTX-(PRM/SA)5 was found to be 70, 90 and 480 minutes respectively. This alternative delivery system of PTX disguised in the form of LBL assembly could have immense application for the treatment of metastasized mammary glands vis-à-vis existing formulation of PTX which is by and large criticized for having certain toxic excipients to be given parentrally. Moreover, the proposed system provides ample of opportunity to modify the surface for targeted application of PTX.

Plateau Inflation in SUGRA-MSSM
We explored a Higgs inflationary scenario in the SUGRA embedding of the MSSM
in Einstein frame where the inflaton is contained in the Higgs doublet.
We include all higher order non-renormalizable terms to the MSSM superpotential
and an appropriate K\"ahler potential which can provide slow-roll inflaton
potential in the flat direction. In this model, a plateau-like inflation
potential can be obtained if the imaginary part of the neutral Higgs acts as
the inflaton. The inflationary predictions of this model are consistent with
the latest CMB observations. The model represents a successful Higgs inflation
scenario in the context of Supergravity and it is compatible with Minimal
Supersymmetric extension of the Standard Model.Comment: 5 pages, 2 figures. Replaced with the journal version. Accepted in
Phys. Lett.
DYNAMIC STACK PORT SERDES POWER UTILIZATION FOR A SUSTAINABLE DATA STACK
Multiple network switches may be stacked, one atop another, and then interconnected through each switch’s two stack ports (SPs). Within such a stack arrangement, techniques are presented herein that support dynamically reducing the power utilization of a switch’s SP Serializer/Deserializer (SerDes) blocks without interrupting any data traffic. Under aspects of the presented techniques, a switch may transition between different power saving modes, which may include a normal mode (encompassing powering down the SerDes blocks of both of the switch’s SPs), an optimized mode (encompassing reducing the speed of the SP SerDes blocks), and a smart mode (encompassing dynamically powering up and down one of the switch’s SPs based on a budgeting of the network traffic). Under further aspects of the presented techniques, the selection of a power saving mode may be based on a switch’s configuration (such as a standalone arrangement, part of a half-ring topology, or part of a full-ring topology) and a switch’s input traffic bandwidth
Sustainable Biomaterials: Current Trends, Challenges and Applications
Biomaterials and sustainable resources are two complementary terms supporting the
development of new sustainable emerging processes. In this context, many interdisciplinary
approaches including biomass waste valorization and proper usage of green technologies, etc.,
were brought forward to tackle future challenges pertaining to declining fossil resources, energy
conservation, and related environmental issues. The implementation of these approaches impels its
potential effect on the economy of particular countries and also reduces unnecessary overburden on
the environment. This contribution aims to provide an overview of some of the most recent trends,
challenges, and applications in the field of biomaterials derived from sustainable resource
A ROBUST NON-BLIND HYBRID COLOR IMAGE WATERMARKING WITH ARNOLD TRANSFORM
Due to development of the internet technologies and other services, requirement of rightful ownership and copyright is highly required. Hence to protect the copyrighted data from unauthorized user, a robust non-blind hybrid color image watermarking scheme is presented. In this proposed scheme, we use color watermark instead of gray watermark which is generally used in most of the existing digital image watermarking techniques. YCbCr color space used to separate the R, G and B channel of images. Y channel of color watermark is embedded into corresponding Y channel of cover image using proposed scheme. Arnold transform are used to scramble the watermark image before embedding process in order to provide more security. The singular value of bands is going to embed with singular values of watermark by making use of variable scaling factor (a). As original image is required at the time of extraction of watermark hence propose scheme belong to non-blind technique group. The two-fidelity parameter namely Peak signal to noise ratio (PSNR) and structural similarity (SSIM) index are used to measure the imperceptibility whereas similarity between original and extracted watermark is measured by using normalized correlation coefficient (NCC). We also compared the results of proposed scheme with other existing watermarking schemes. The experimental results prove effectiveness of the proposed image watermarking scheme in term of robustness and imperceptibility
A comparative study of dexmedetomidine versus clonidine in epidural anaesthesia to assess the level of sedation in patients undergoing lower abdominal and lower limb surgery
Background: To compare study of dexmedetomidine versus clonidine in epidural anesthesia to assess the level of sedation in patients undergoing lower abdominal and lower limb surgery.Methods: This was a comparative study conducted on admitted ASA grade I and II patients undergoing lower abdominal and lower limb surgeries. The patients were divided into three groups of 30 patients each, according to the epidural medication they received:-Group A-received 15ml of bupivacaine (0.5%) and dexmedetomidine (1.0µg/kg body weight) in 1ml of normal saline; Group B-received 15ml of bupivacaine (0.5%) and clonidine (2.0µg/kg body weight) in 1ml of normal saline; Group C-received 15ml of bupivacaine (0.5%) with 1ml of normal saline. The heart rate, blood pressure, sensory dermatome level, Motor blocked level, pain and VAS were recorded at different time intervals. The side effects were also noted.Results: The baseline parameters were comparable among the groups. All the hemodynamic parameters and other study parameters were similar at Min. 0. All the hemodynamic parameters such as heart rate, blood pressure and SpO2 were variable at different time intervals. Motor block level  was significantly (p<0.05) lower in Group C than Group A and Group B from Min 50 to Min 90. The sedation score was observed to be nil in Group C. The post-op pain score became higher in Group C than Group A and Group B at subsequent time intervals. A 3 (10%) of the rescue agents was observed in Group C. Atropine (30%) and mephenteramine (10%) were common rescue agents in Group B. The bradycardia was observed in 30% patients of Group B and in 40% of Group A.Conclusions: On addition of dexmedetomidine as adjuvant to bupivacaine in epidural anesthesia provides better anesthesia and sedation than clonidine as adjuvant to bupivacaine or bupivacaine alone with mild hemodynamic changes which are easily manageable
Antiangiogenic activity of zinc and zinc-sorafenib combination using the chick chorioallantoic membrane assay: a descriptive study
Background: Zinc, a trace element, is known for downregulating several proangiogenic growth factors and cytokines. However, its antiangiogenic activity is not adequately studied. The present study was aimed to evaluate the possible antiangiogenic activity of zinc via the chick chorioallantoic membrane (CAM) assay. Also, the antiangiogenic activity of the combination therapy of zinc with various doses of sorafenib, a tyrosine kinase inhibitor, was evaluated.Methods: A pilot study was initially conducted so as to select suitable doses of zinc and sorafenib. The antiangiogenic activity after combining zinc 2.5 μg/embryo with sorafenib 1, and 2 μg/embryo was also evaluated. The antiangiogenic activity was quantified in terms of total length of blood vessels, number of junctions, number of branching points, and mean length of the blood vessels.Results: Zinc 2.5 μg/embryo showed significant (p 0.05) to that of sorafenib 2 μg/embryo.Conclusions: Zinc caused significant antiangiogenic activity in the CAM assay. The lack of addition/synergism in the zinc-sorafenib combination could have been due to the variability in the dose/ratio selection. Addition of zinc to sorafenib therapy could improve treatment tolerability, reduce cost of therapy, and reduce the emergence of drug resistance. Future mechanistic studies could identify the exact pharmacodynamics of zinc as an angiogenesis inhibitor
Mechanochemical synthesis of a new triptycene-based imine-linked covalent organic polymer for degradation of organic dye
In the present work, a novel triptycene-based imine-linked covalent organic polymer (TP-COP) was designed and synthesized via room-temperature, solvent-free mechanochemical grinding. The as-synthesized TP-COP material was fully characterized by Fourier transform infrared spectroscopy, solid-state NMR, field emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM), Brunauer-Emmett-Teller method, thermogravimetric analysis, diffuse reflectance spectroscopy (DRS), and electron paramagnetic resonance (EPR). The HRTEM image of TP-COP clearly indicates the presence of graphene-like layered morphology (exfoliated layers). The DRS study reveals that TP-COP exhibited a low optical band gap value of 2.49 eV, implying its semiconducting nature. Further, the EPR study confirmed the semiconducting behavior of TP-COP through the generation of free radicals. These findings suggest that TP-COP could be used as an efficient photocatayst for the degradation of organic dye (RhB) under solar irradiation. Moreover, TP-COP showed excellent reusability in degrading dye (RhB) without obvious performance decay
Antibody responses to the BBV152 vaccine in individuals previously infected with SARS-CoV-2: A pilot study
Background & objectives: Vaccination against SARS-CoV-2 is a recommendation from the World Health Organization as the foremost preference in the current situation to control the COVID-19 pandemic. BBV152 is one of the approved vaccines against SARS-CoV-2 in India. In this study, we determined SARS-CoV-2–specific antibody levels at day 0 (baseline, before vaccination), day 28 ± 2 post-first dose (month 1) and day 56 ± 2 post-first dose (month 2) of BBV152 whole-virion–inactivated SARS-CoV-2 recipients, and compared the antibody responses of individuals with confirmed pre-vaccination SARS-CoV-2 infection to those individuals without prior evidence of infection.
Methods: Blood samples were collected from 114 healthcare professionals and frontline workers who received BBV152 vaccine from February to May & June 2021. Prior infection with SARS-CoV-2 was determined at baseline. Serum samples were used to estimate SARS-CoV-2 nucleoprotein-specific IgG [IgG (N)], spike protein-specific IgG [IgG (S)] and neutralizing antibodies (NAb).
Results: Participants with previous SARS-CoV-2 infection after a single vaccine dose elicited IgG (N) and IgG (S) antibody levels along with NAb binding inhibition responses levels were similar to infection-naïve vaccinated participants who had taken two doses of vaccine.
Interpretation & conclusions: Our preliminary data suggested that a single dose of BBV152-induced humoral immunity in previously infected individuals was equivalent to two doses of the vaccine in infection-naïve individuals. However, these findings need to be confirmed with large sized cohort studies
Discovery of unusual pulsations in the cool, evolved Am stars HD 98851 and HD 102480
The chemically peculiar (CP) stars HD 98851 and HD 102480 have been
discovered to be unusual pulsators during the ``Naini Tal Cape Survey''
programme to search for pulsational variability in CP stars. Time series
photometric and spectroscopic observations of these newly discovered stars are
reported here. Fourier analyses of the time series photometry reveal that HD
98851 is pulsating mainly with frequencies 0.208 mHz and 0.103 mHz, and HD
102480 is pulsating with frequencies 0.107 mHz, 0.156 mHz and 0.198 mHz. The
frequency identifications are all subject to 1 d cycle count
ambiguities. We have matched the observed low resolution spectra of HD 98851
and HD 102480 in the range 3500-7400 \AA with theoretical synthetic spectra
using Kurucz models with solar metallicity and a micro-turbulent velocity 2 km
s. These yield K, log for HD 98851
and K, log for HD 102480. We
determined the equivalent H-line spectral class of these stars to be F1 IV and
F3 III/IV, respectively. A comparison of the location of HD 98851 and HD 102480
in the HR diagram with theoretical stellar evolutionary tracks indicates that
both stars are about 1-Gyr-old, 2- stars that lie towards the red
edge of the Sct instability strip. We conclude that HD 98851 and HD
102480 are cool, evolved Am pulsators. The light curves of these pulsating
stars have alternating high and low amplitudes, nearly harmonic (or
sub-harmonic) period ratios, high pulsational overtones and Am spectral types.
This is unusual for both Am and Sct pulsators, making these stars
interesting objects.Comment: 9 pages, 6 Figures, Accepted for publication in MNRA
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