1,823 research outputs found
Constraining gravity by dynamical system analysis
The evolutionary behavior of the Universe has been analysed through the
dynamical system analysis in gravity, where , , ,
and respectively represent torsion, boundary term, teleparallel
Gauss-Bonnet term and Gauss-Bonnet boundary term. We use the transformation,
in order to obtain the
deviation from the Teleparallel Equivalent of General Relativity (TEGR). Two
cosmological models pertaining to the functional form of have been studied. The well motivated forms are: (i) and (ii) . The evolutionary phases of the Universe have
been identified through the detailed analysis of the critical points. Further,
with the eigenvalues and phase space diagrams, the stability and attractor
nature of the accelerating solution have been explored. The evolution plots
have been analyzed for the corresponding cosmology and compatibility with the
present observed value of standard density parameters have been shown.Comment: 17 pages, 4 figures, 6 tables. Constructive comments are welcom
Preliminary phytochemistry and antimicrobial activity of bark of Bauhinia racemosa Lamk.
The bark of Bauhinia racemosa are reported to have great medicinal value. Phytochemical screening of the plant bark reveals the presence of carbohydrates, alkaloids, steroids and tannins. the methanol, ethanol, aqueous, acetone and petroleum ether extracts of bark of B. racemosa Lamk. prepared and antimicrobial activity were studied by agar well diffusion method against enteric bacterial pathogens such as E. coli, S. aureus, B. subtilis, P. aeruginosa and fungi A. niger and C.albicans. The methanol extracts had wide range of antimicrobial activity against enteric microbes than ethanol extracts, where as ethanol extract were slightly higher antibacterial activity than aqueous extract. Antimicrobial activity of various extracts of bark of B. racemosa was carried in attempt to develop a new pharmaceutical drug from natural origin for prevention of enteric infection
Effect of chemotherapy on serum nitric oxide levels in advanced stage breast cancer patients
Background: The role of nitric oxide is still unclear in advanced breast cancer patients undergoing adjuvant chemotherapy. This study was undertaken to investigate the effect of chemotherapy on serum nitric oxide levels in advanced stage breast cancer patients.Methods: In this observational study, clinically and histopathologically proven sixty female patients with advanced stage breast cancer were included. According to Tumor-Node-Metastasis (TNM) classification, patients were further grouped as stage III and stage IV. Thirty healthy and age-matched female controls were selected for comparison. Blood was collected from healthy controls and from breast cancer patients after surgery prior to chemotherapy and after three weeks of administration of first adjuvant chemotherapy cycle. Serum nitric oxide levels were measured by spectrophotometric method.Results: Significantly higher concentrations of serum nitric oxide were observed in breast cancer patients before chemotherapy in stage III (p<0.0001) and stage IV (p<0.0001) of the disease as compare to concentrations in healthy controls. The serum levels of nitric oxide were significantly decreased in stage III as well as stage IV of breast cancer patients after three weeks of receiving first adjuvant chemotherapy cycle as compare to levels before chemotherapy (p<0.0001), however serum nitric oxide levels were higher in stage III (p=0.0036) and stage IV (p<0.0001) of the disease as compare to healthy controls.Conclusions: Chemotherapy drug administration causes decrease in serum nitric oxide levels in advanced stages of breast cancer patients. Monitoring serum nitric oxide levels could be used to predict patients’ response to chemotherapy treatment in breast cancer
Type-Ahead Search in XML data based on Improved Forward Index Structure: ATASK
The keyword based search system is most widely used in many real time applications for getting the required information from huge amount of dataset in quick time. There are many keyword search based systems and methods presented by various authors already, as the time goes, this methods becomes inefficient in different ways. The all previous methods did not work for search XML data in mode of type-ahead search, and hence it is not trivial to extend existing techniques to support fuzzy type-ahead search in XML data. Previous methods are not purely based on XML data and as XML data is consisting of parent and child nodes, it is complex to understand such format to read for existing methods. Existing methods directly works on single document. Thus to overcome the limitations of existing methods, we need to have efficient XML based type-ahead shear method. Recently we have studied one such method, which is called as TASX (pronounced “task”). This is fuzzy type-ahead search method in XML data. This method searches the XML data during the typing of keyword from user end and it searches XML data even if it’s misspelled. Experimentally this method showing efficient performance as compared to existing methods, but there are still suggestions over this method for improvement. Here, we are presenting extended approach for XML based type-ahead search method ATASX (pronounced “a task”). In this method we are proposing to use improved forward-index structure method with aim of improving the search efficiency it reduces searching time and provides result quality
Noether Symmetries in Cosmology
All degrees of freedom related to the torsion scalar can be explored by
analysing, the gravity formalism where, is a torsion scalar and
is the teleparallel counterpart of the Gauss-Bonnet topological invariant
term. The well-known Noether symmetry approach is a useful tool for selecting
models that are motivated at a fundamental level and determining the exact
solution to a given Lagrangian, hence we explore Noether symmetry approach in
gravity formalism with three different forms of and study
how to establish nontrivial Noether vector form for each one of them. We extend
the analysis made in \cite{capozziello2016noether} for the form
and discussed the symmetry for this
model with linear teleparallel equivalent of the Gauss-Bonnet term, followed by
the study of two models containing exponential form of the teleparallel
equivalent of the Gauss-Bonnet term. We have shown that all three cases will
allow us to obtain non-trivial Noether vector which will play an important role
to obtain the exact solutions for the cosmological equations.Comment: 12 page
Accelerating Cosmological Models in Gravitational Theory
In this paper, we have explored the field equations of f(T, B) gravity as an
extension of teleparallel gravity in an isotropic and homogeneous space time.
In the basic formalism developed, the dynamical parameters are derived by
incorporating the power law and exponential scale factor function. The models
are showing accelerating behaviour and approaches to CDM at late
time.The present value of the equation of state parameter for both the cases
are obtained to be in accordance with the range provided by cosmological
observations. The geometrical parameters and the scalar field reconstruction
are performed to assess the viability of a late time accelerating Universe.
Further the stability of both the models are presented. It has been observed
that both the models are parameters dependent. Since most of the geometrically
modified theories of gravity are favouring the violation of strong energy
condition, we have derived the energy conditions both for the power law and
exponential model. In both the models, the violation of strong energy condition
established.Comment: 14 Pages, 9 figure
Use of Fixed Dose Combination (FDC) Drugs in India: Central Regulatory Approval and Sales of FDCs Containing Non-Steroidal Anti-Inflammatory Drugs (NSAIDs), Metformin, or Psychotropic Drugs.
In 2012, an Indian parliamentary committee reported that manufacturing licenses for large numbers of fixed dose combination (FDC) drugs had been issued by state authorities without prior approval of the Central Drugs Standard Control Organization (CDSCO) in violation of rules, and considered that some ambiguity until 1 May 2002 about states' powers might have contributed. To our knowledge, no systematic enquiry has been undertaken to determine if evidence existed to support these findings. We investigated CDSCO approvals for and availability of oral FDC drugs in four therapeutic areas: analgesia (non-steroidal anti-inflammatory drugs [NSAIDs]), diabetes (metformin), depression/anxiety (anti-depressants/benzodiazepines), and psychosis (anti-psychotics)
Pharmacovigilance in India, Uganda and South Africa with reference to WHO's minimum requirements.
BACKGROUND: Pharmacovigilance (PV) data are crucial for ensuring safety and effectiveness of medicines after drugs have been granted marketing approval. This paper describes the PV systems of India, Uganda and South Africa based on literature and Key Informant (KI) interviews and compares them with the World Health Organization's (WHO's) minimum PV requirements for a Functional National PV System. METHODS: A documentary analysis of academic literature and policy reports was undertaken to assess the medicines regulatory systems and policies in the three countries. A gap analysis from the document review indicated a need for further research in PV. KI interviews covered topics on PV: structure and practices of the system; current regulatory policy; capacity limitations, staffing, funding and training; availability and reporting of data; and awareness and usage of the systems. Twenty interviews were conducted in India, 8 in Uganda and 11 in South Africa with government officials from the ministries of health, national regulatory authorities, pharmaceutical producers, Non-Governmental Organizations (NGOs), members of professional associations and academia. The findings from the literature and KI interviews were compared with WHO's minimum requirements. RESULTS: All three countries were confronted with similar barriers: lack of sufficient funding, limited number of trained staff, inadequate training programs, unclear roles and poor coordination of activities. Although KI interviews represented viewpoints of the respondents, the findings confirmed the documentary analysis of the literature. Although South Africa has a legal requirement for PV, we found that the three countries uniformly lacked adequate capacity to monitor medicines and evaluate risks according to the minimum standards of the WHO. CONCLUSION: A strong PV system is an important part of the overall medicine regulatory system and reflects on the stringency and competence of the regulatory bodies in regulating the market ensuring the safety and effectiveness of medications. National PV systems in the study countries needed strengthening. Greater attention to funding is needed to coordinate and sustain PV activities. Our study highlights a need for developing more systematic approaches to regularly monitoring and evaluating PV policy and practices
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Suppression of Harmaline Tremor by Activation of an Extrasynaptic GABAA Receptor: Implications for Essential Tremor
Background: Metabolic imaging has revealed excessive cerebellar activity in essential tremor patients. Golgi cells control cerebellar activity by releasing gamma-aminobutyric acid (GABA) onto synaptic and extrasynaptic receptors on cerebellar granule cells. We postulated that the extrasynaptic GABAA receptor-specific agonist THIP (gaboxadol; 4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol) would suppress tremor in the harmaline model of essential tremor and, since cerebellar extrasynaptic receptors contain α6 and δsubunits, would fail to do so in mice lacking either subunit.
Methods: Digitally measured motion power, expressed as 10–16 Hz power (the tremor bandwidth) divided by background 8–32 Hz motion power, was accessed during pre-harmaline baseline, pre-THIP harmaline exposure, and after THIP administration (0, 2, or 3 mg/kg). These low doses were chosen as they did not impair performance on the straight wire test, a sensitive test for psychomotor impairment. Littermate δ wild-type and knockout (Gabrd+/+, Gabrd–/–) and littermate α6 wild-type and knockout (Gabra6+/+, Gabra6–/–) mice were tested.
Results: Gabrd+/+ mice displayed tremor reduction at 3 mg/kg THIP but not 2 mg/kg, and Gabra6+/+ mice showed tremor reduction at 2 and 3 mg/kg. Their respective subunit knockout littermates displayed no tremor reduction compared with vehicle controls at either dose.
Discussion: The loss of anti-tremor efficacy with deletion of either δ or α6 GABAA receptor subunits indicates that extrasynaptic receptors containing both subunits, most likely located on cerebellar granule cells where they are highly expressed, mediate tremor suppression by THIP. A medication designed to activate only these receptors may display a favorable profile for treating essential tremor
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