Different methods of fluoride delivery in prevention of white spot lesions in orthodontics

Orthodontic patients on fixed appliances are at an increased risk of developing white spot lesions which can progress to frank cavitations. Fluoride application in different forms has been shown to be effective in the reduction of formation of white spot lesions. The aim of this short communication is to discuss different methods that have been used in prevention of white spot lesions in orthodontic patients. Daily mouth rinse using 0.05% sodium fluoride is the most efficacious method in prevention of white spot lesions. It is thereby recommended for use in conjunction with proper maintenance of oral hygiene.Keywords: Demineralisation; Fluoride; Glass Ionomer; Compomer; Orthodontic

Tunneling through two resonant levels: fixed points and conductances

We study point contact tunneling between two leads of a Tomonaga-Luttinger liquid through two degenerate resonant levels in parallel. This is one of the simplest cases of a quantum junction problem where the Fermi statistics of the electrons plays a non-trivial role through the Klein factors appearing in bosonization. Using a mapping to a `generalized Coulomb model' studied in the context of the dissipative Hofstadter model, we find that any asymmetry in the tunneling amplitudes from the two leads grows at low temperatures, so that ultimately there is no conductance across the system. For the symmetric case, we identify a non-trivial fixed point of this model; the conductance at that point is generally different from the conductance through a single resonant level.Comment: 6 pages, 3 figure

Study of immunomodulators from various plant species

INTRODUCTION : An immune system is a system of biological structures and processes within an organism that protects against invading micro organisms by identifying and killing pathogens and tumor cells. It detects a wide variety of agents, from viruses to parasitic worms and needs to distinguish them from the organism's own healthy cells and tissues in order to function properly. The immune mechanisms may vary from species to species. Unicellular organisms such as bacteria possess enzyme systems that protect against viral infections. Jawed vertebrates, the Gnathostomes including humans, have even more sophisticated defence mechanisms which consists many types of proteins, cells, organs, and tissues that interact in an elaborate and dynamic network. Immune system is vulnerable to the free radical-induced oxidative stress. The cellular and humoral components of the immune system are particularly sensitive to increased levels of reactive oxygen species, which may cause premature immunosenescence. The immune response can be manipulated to suppress unwanted responses resulting from autoimmunity, allergy and transplant rejection and to stimulate protective responses against pathogens that largely elude the immune system. The modulation of immune response with the aid of various bioactives in order to alleviate certain diseases is an active area of interest. Immunomodulators are substances that have been shown to modify the immune systems response to a threat upon it. They modulate and potentiate the weapons of our immune system keeping them in a highly prepared state for any threat it may encounter. They increase the immune responsiveness of the body against pathogens by activating primarily the non-specific immune system. AIM : With the advancement of Science and Technology, the occurrence of diseases can be easily visualized by the health professionals. Our immune system detects a wide variety of agents, from viruses to parasitic worms, kills and disposes using various immune mechanisms. Disorders in the immune system can result in disease, including autoimmune diseases, inflammatory diseases and cancer. Although some studies have been successful, complete cure is still a major challenge. Herbal medicine has become an integral part of health care system, based on the combination of ayurvedic or traditional classics and ongoing scientific research. To address this challenge, certain medicinal plants with immunomodulant activity, will be selected and studied. The aim of this study was to validate the immunomodulant potential of two different plant species using in vitro experimental models and to provide scientific evidence to the ethnomedicinal use of the plant species. Finally, they were incorporated into a novel carrier called phytosome to promote its therapeutic action significantly. The principal goal was to conceptualize an ideal drug delivery system viz. phytosomes for the selected plant species using different types of phospholipids. The novel carriers loaded with bioactives not only deliver the drug(s) to specific organs within the body but also controls the delivery rate. Thus, using this novel drug delivery system, herbal drugs incorporated with phospholipids, it might be able to achieve constant and uniform concentration of the drug for longer period of time in the body. OBJECTIVES : To identify two different plant species which had been traditionally used to treat various ailments and extract the possible phytoconstituents using solvents of increasing polarity. • To perform systematic studies on the selected plants - Nymphaea nouchali (Nn) and Trichosanthes dioica (Td) for substantiating their therapeutic claims. • To investigate the immunomodulatory effects of different extracts of Nymphaea nouchali (Nn) and Trichosanthes dioica (Td) using in vitro assay methods. • To perform acute oral toxicity studies for the selected plant extracts of Nymphaea nouchali (Nn) and Trichosanthes dioica (Td) and thereby to identify the maximum tolerated dose (MTD). • To identify the selected plant extracts by spectroscopic methods (UV and IR). • To design and fabricate a novel drug delivery system using phytosomes, for effective delivery of herbal constituents. • To optimize the ratio of drug and phospholipids having an ideal spherical shape and an effective average particle size range. • To identify the best formulation which maintains steady state plasma drug concentration for prolonged period of time. • To summarize and finalize the obtained results by comparing with a standard using in vivo animal models for immunomodulant activity. MATERIALS AND METHODS : The selected plant species Nymphaea nauchali (Nn) and Trichosanthes dioica (Td) were extracted using soxhlet apparatus by successive solvent extraction technique. Five different solvents of increasing polarity (n-Hexane, Chloroform, Ethyl acetate, Methanol and Distilled water) were used for the extraction process. All the extracts were subjected to preliminary phytochemical investigations and in vitro immunomodulatory studies such as Nitroblue tetrazolium (NBT) assay and cellular lysosomal enzyme activity. Then the selected plant extracts were identified by means of UV-Visible and Infra Red spectroscopic methods. Acute toxicity studies were performed according to Organization for Economic Cooperation and Development (OECD) guidelines 425, received from CPCSEA, Ministry of Social Justice and Empowerment, Government of India30. Swiss albino mice weighing between 20-25 g in groups of six were used (n=6). The animals were fasted for 4 h with free access to water only. The both Nn and Td extracts were administered orally in doses of 2000 mg/kg to different groups of mice and observed for 14 days for mortality and physical/behavioural changes. The experiments were performed after the experimental protocols had been approved by the Institutional Animal Ethical Committee (183/SASTRA/IAEC/RPP). The phytosomes were prepared by combining the two methanolic extracts (Nn and Td) in an equimolar amount with various ratios of phospholipids using solvent evaporation technique31. The ratio of drug and phospholipid employed was 1:1, 1:2, 1:4, 1:6, 1:8 and 1:10. Thereby four batches of formulations each containing six formulae, totally 24 formulations were made using four different types of phospholipids such as phosphatidic acid (PA), phosphatidyl choline (PC), phosphatidyl ethanolamine (PE) and phosphatidyl serine (PS). Among the 24 phytosomal formulations, the one which produced better physicochemical characteristics, entrapment efficiency and sustained drug release for highest duration was selected for further in vivo studies. INFERENCE : From the preliminary phase of this research work, it was observed that alkaloids, flavonoids, proteins & free aminocids, saponins, tannins & phenolic compounds and terpenoids were the phytoconstituents present in the methanolic extract of Nymphaea nouchali and Trichosanthes dioica. These phytoconstituents might play an effective role to bring out electron-transferring system and intracellular killing in in vitro immunomodulatory assays which gives them an immuno modulation property. CONCLUSION : The methanolic extracts of two botanicals, Nymphaea nouchali and Trichosanthes dioica, were converted into phytosomes and evaluated for immunomodulatory activity. The therapeutic regimen of phytosomes containing both the plant extracts was able to produce significant synergistic immunostimulatory action. Phytosome formulations containing combined plant extracts have produced effective immunomodulant activity as compared to plain extracts and standard drug. These findings are very much promising that phytosome technology can be safely used to incorporate the phytoconstituents in various ratios using suitable phospholipids. The results of this research work provide a scientific evidence for the traditional use of Nymphaea nouchali and Trichosanthes dioica. Also the phytosome technology can offer an alternative therapy for the treatment of many ailments including AIDS, TB, etc and might be used in immunocompromised patients for boosting their immune system

Effects of interaction on an adiabatic quantum electron pump

We study the effects of inter-electron interactions on the charge pumped through an adiabatic quantum electron pump. The pumping is through a system of barriers, whose heights are deformed adiabatically. (Weak) interaction effects are introduced through a renormalisation group flow of the scattering matrices and the pumped charge is shown to {\it always} approach a quantised value at low temperatures or long length scales. The maximum value of the pumped charge is set by the number of barriers and is given by $Q_{\rm max} = n_b -1$. The correlation between the transmission and the charge pumped is studied by seeing how much of the transmission is enclosed by the pumping contour. The (integer) value of the pumped charge at low temperatures is determined by the number of transmission maxima enclosed by the pumping contour. The dissipation at finite temperatures leading to the non-quantised values of the pumped charge scales as a power law with the temperature ($Q-Q_{\rm int} \propto T^{2\alpha}$), or with the system size ($Q-Q_{\rm int} \propto L_s^{-2\alpha}$), where $\alpha$ is a measure of the interactions and vanishes at $T=0 ~(L_s=\infty)$. For a double barrier system, our result agrees with the quantisation of pumped charge seen in Luttinger liquids.Comment: 9 pages, 9 figures, better quality figures available on request from author

A Study on Vatha Karappan (வாத கரப்பான்)

The present studies is Karappan is a dermatological disease that causes many patients in despair. It is a major health hazard in the developing countries like India. People who live in densely populated areas with poor hygiene facilities, lack of personal and environmental hygiene, change in life style, diet habits, and use of artificial cosmetics, chemical constituents are the common factors that precipitate this disease. So when the disease once occurrs, remission and relapse happens subsequently throughout the life of the patient. The frequency of relapse depends upon the individual immune power. The author has selected this disease for the dissertation work to evolve a better treatment for getting rid of this disease, once for all. When selecting an appropriate drug to try, the author had decided to go for a pure herbal drug Perumarapattai chooranam internal and Herbo Mineral drug Pungu thylum external. The principal object of this study is to have a clinical trial on Vatha Karappan patients with trial drugs Perumarapattai chooranam (internal) and Pungu thylam (external). To create awareness about the Siddha science and to highlight the efficacy of Siddha drugs among the public. To have an idea of an incidence of Karappan with reference to age, life style, occupation, socio economical status, family history, and seasonal variations. To know how the disease alters the normal conditions under the topics of Mukkutram, Poripulangal, Envagai thervugal, Udar kattugal, Neerkuri and Neikuri. To evaluate the biochemical and pharmacological analysis of the trial drugs. To use the modern diagnostic parameters to endorse the diagnosis and follow the progression of the disease. To make an awareness among the people about the prevention of the disease. To know the extent of correlation of etiology, classification, signs and symptoms of Vatha Karappan in Siddha aspect with Eczema in modern aspect. When Perumarapattai chooranam and Pungu thylum were administered to the Vatha Karappan patient, following results were observed. Results show that 72.5 % of patients showed good relief and 27.5% cases had moderate relief. The disseration drug was very effective to the patients and there was no recurrences of symptoms were reported. cost of the drug is very cheap and free from side effect. So they are useful for long term purposes Hereby the author concludes that the treatment with drug Perumarapattai Chooranam (internal) and Pungu thylam (external) for Vatha Karappan was found very effective in point of efficacy and safety

Hepatoprotective Activity of Melia azedarach.L Against Carbontetrachloride- Induced Hepatic Damage In Rats

Abstract The leaves of Melia azedarach.L, family Meliaceae was tested for hepatoprotective activity against CCl 4 in rats. The ethanol extract of Melia azedarach.L has shown significant activity, lowering the serum enzymes like SGOT and SGPT in rats intoxicated with CCl 4

SCHEMING ECHOING CIRCUIT TO DECREASE THE SWITCHING LOSSES AND BRIDGE CURRENTS

As compared to the conventional DABs, the suggested topology considerably cuts down on the bridge currents, lowering both conduction and switching losses and increasing the bridge power factors. This paper proposes a resonant dual-active bridge (DAB) ripper tools, which utilizes a tuned capacitor-inductor-capacitor network. The viability from the suggested concept is verified through simulation. A mathematical model, which predicts the behavior from the suggested system, is given to reveal that both magnitude and direction from the power flow can be controlled most likely through relative phase position or pulse width modulation of voltages created through the bridges. Experimental outcomes of prototype ripper tools that have efficiency at rated power, will also be given discussions to show the raised performance of the topology. Simulations were performed with MATLAB within the frequency domain so the frequency dependent resistances proven. The experimental values track the theoretical values quite carefully-the theoretical calculations don't look at the dynamic facets of the IGBT switching losses, nor the 350-ns conduction dead band between devices inside a leg

Comparison of Hybrid PSO-SA Algorithm and Genetic Algorithm for Classification

In this work, we propose and present a Hybrid particle swarm optimization-Simulated annealing algorithm and compare it with a Genetic algorithm for training respectively neural networks of identical architectures. These neural networks were then tested on a classification task. In particle swarm optimization, behavior of a particle is influenced by the experiential knowledge of the particle as well as socially exchanged information. Particle swarm optimization follows a parallel search strategy. In simulated annealing uphill moves are made in the search space in a stochastic fashion in addition to the downhill moves. Simulated annealing therefore has better scope of escaping local minima and reach a global minimum in the search space. Thus simulated annealing gives a selective randomness to the search. Genetic algorithm performs parallel and randomized search. The goal of training the neural network is to minimize the sum of the squares of the error between the target and observed output values for all the training samples and to deliver good test performance on the test inputs. We compared the performance of the neural networks of identical architectures trained by the  Hybrid particle swarm optimization-simulated annealing and Genetic algorithm respectively on a classification task and noted the results obtained. Neural network trained by Hybrid particle swarm optimization-simulated annealing has given better results compared to the neural network trained by the Genetic algorithm in the tests conducted by us. Keywords: Classification, Hybrid particle swarm optimization-Simulated annealing, Simulated Annealing, Genetic algorithm, Neural Network etc

Awareness and usage of Academic Social Networking Sites: Female Research Scholars and Faculties

The study examines the awareness and usage of Academic Social Networking Sites (ASNS) among female research scholars and faculty members in Tamil Nadu, India. A structured questionnaire was used to survey 838 female research scholars through online platforms. The results showed that most respondents use at least one ASNS, with Google Scholar being the most popular. The primary reasons for using ASNS are to disseminate scholarly work and discover research papers. However, a lack of awareness and time was the main reason for not having an account with these sites. The respondents learned about ASNS primarily through friends and colleagues and suggested increasing their use and awareness through seminars and training courses, library posters, and integration in the student courses. The study highlights the importance of ASNS in the research work of female scholars and faculties while also recognizing the need for increased awareness and access to these resources