Residual Stress Developments During Laser Welding of Commercially Pure Titanium Sheets

The laser welding of cp-ti sheet was done by using a continuous wave welding and gas laser (CO2).Laser welding is operating at different conditions like laser power at 2kW & 2.5kW, range of welding speed is from 4m/min to 8m/min and laser intensity distribution by Gaussian Mode and Donut Mode. Macrostructure of weld size and fusion zone were examined by using optical microscope. It is found that weld size was decreased with increasing welding speed and increased with increasing laser power and spot diameter and weld size for donut mode is higher than the Gaussian mode. Residual stress which is developed due to thermal gradient is measured by X-Ray Diffraction Technique. These residual stress measurements were taken at a series on the top surface covering the fusion zone, heat affected zone (HAZ) and base metal. Here residual stress is compressive in nature. Residual stress at weld pool for Gaussian mode is lower compared to Donut mode

In Vivo Bioavailability and Therapeutic Assessment of Host-Guest Inclusion Phenomena for the Hydrophobic Molecule Etodolac: Pharmacodynamic and Pharmacokinetic Evaluation

The aim of present investigation was 1) to evaluate the in vivo bioavailability of an Etodolac (ETD)-β-cyclodextrin (β-CD) inclusion complex system prepared by kneading and spray drying techniques in rats, 2) to study the pharmacodynamic parameters in various animal models for analyzing the therapeutic response and, 3) to evaluate the pharmacokinetic profile of the drug administered. Inclusion complexation with β-CD enhanced the solubility of the drug, improved bioavailability and reduced ulcerogenicity of ETD in rats. Pharmacodynamic studies were carried out in normal LACA mice and pharmacokinetic evaluation was done in male Wistar rats. Pharmacokinetic parameters evaluated for the inclusion complexes revealed good correlation. The minimum dose necessary to produce analgesic or anti-arthritic activity was also decreased, indicating that the host-guest strategy that uses β-CD and ETD was very effective and could be successfully employed in the preparation of pharmaceutical formulations of anti-arthritics and analgesics

Paradoxical effect of coating on natural guar gum blended carbomer matrix systems for the neurological depressive disorders

Oral extended release products offer potential advantages in patient compliance and therapeutic outcomes like sustained blood levels with attenuation of adverse effects. In neuropsychiatric disorders like depression, most of the formulations serve a marketing objective rather than a clinical objective. The present investigation was aimed to develop a once daily sustained release formulation for delivery of an acid-labile, water soluble antidepressant, duloxetine HCl. The formulation was pragmatically designed using blend of natural and synthetic polymeric biomaterials that it releases the drug at alkaline pH in a sustained manner. The basic intention was to develop a tablet formulation with hydrophilic matrix core, using blend of release retarding natural biodegradable polymers such as guar gum, carbopol 71G-NF (a synthetic carbomer) and C-Pharm® gel. Barrier coating using HPMC-E5 was given to retard the initial release followed by enteric coating with HPMC-AS to prevent exposure of drug in acidic mileau of the stomach. The formulation exhibited desired release pattern and was described best-fit by Hixon-Crowell model. Stability analysis under stress conditions up to one month displayed good reproducibility. The matrix tablets successfully decreased the symptoms of depression (significant decrease in immobility time) in a rat forced swimming model. Pharmacokinetic data of the formulation revealed (tmax ~ 6 h, Cmax ~ 1157.58 ng/ml, mean AUCt~11145.04 ng*h/ml, and Ka~1.07h-1) good correlation in all animals.Keywords: Matrix tablets; Duloxetine HCl; Sustained release; Enteric coating; Hixon-crowell mode

Paradoxical effect of coating on natural guar gum blended carbomer matrix systems for the neurological depressive disorders

Oral extended release products offer potential advantages in patient compliance and therapeutic outcomes like sustained blood levels with attenuation of adverse effects. In neuropsychiatric disorders like depression, most of the formulations serve a marketing objective rather than a clinical objective. The present investigation was aimed to develop a once daily sustained release formulation for delivery of an acid-labile, water soluble antidepressant, duloxetine HCl. The formulation was pragmatically designed using blend of natural and synthetic polymeric biomaterials that it releases the drug at alkaline pH in a sustained manner. The basic intention was to develop a tablet formulation with hydrophilic matrix core, using blend of release retarding natural biodegradable polymers such as guar gum, carbopol 71G-NF (a synthetic carbomer) and C-Pharm® gel. Barrier coating using HPMC-E5 was given to retard the initial release followed by enteric coating with HPMC-AS to prevent exposure of drug in acidic mileau of the stomach. The formulation exhibited desired release pattern and was described best-fit by Hixon-Crowell model. Stability analysis under stress conditions up to one month displayed good reproducibility. The matrix tablets successfully decreased the symptoms of depression (significant decrease in immobility time) in a rat forced swimming model. Pharmacokinetic data of the formulation revealed (tmax ~ 6 h, Cmax ~ 1157.58 ng/ml, mean AUCt~11145.04 ng*h/ml, and Ka~1.07h-1) good correlation in all animals.Keywords: Matrix tablets; Duloxetine HCl; Sustained release; Enteric coating; Hixon-crowell mode

The Overlapping Community Structure of Structural Brain Network in Young Healthy Individuals

Community structure is a universal and significant feature of many complex networks in biology, society, and economics. Community structure has also been revealed in human brain structural and functional networks in previous studies. However, communities overlap and share many edges and nodes. Uncovering the overlapping community structure of complex networks remains largely unknown in human brain networks. Here, using regional gray matter volume, we investigated the structural brain network among 90 brain regions (according to a predefined anatomical atlas) in 462 young, healthy individuals. Overlapped nodes between communities were defined by assuming that nodes (brain regions) can belong to more than one community. We demonstrated that 90 brain regions were organized into 5 overlapping communities associated with several well-known brain systems, such as the auditory/language, visuospatial, emotion, decision-making, social, control of action, memory/learning, and visual systems. The overlapped nodes were mostly involved in an inferior-posterior pattern and were primarily related to auditory and visual perception. The overlapped nodes were mainly attributed to brain regions with higher node degrees and nodal efficiency and played a pivotal role in the flow of informa- tion through the structural brain network. Our results revealed fuzzy boundaries between communities by identifying overlapped nodes and provided new insights into the understanding of the relationship between the structure and function of the human brain. This study provides the first report of the overlapping community structure of the structural network of the human brain

Solid Lipid Nanoparticles (SLN’S) – Trends and Implications in Drug Targeting

The era of nanotechnology has revolutionized the drug delivery system and persuades new research strategies to flourish. Solid lipid nanoparticles (SLN) has attracted various research groups and companies since the early 1990s, however research in the SLNs is still in its infancy. ‘SLN technology based therapy’ made available a novel and sound platform for therapeutics. Solid lipid nanoparticles have been developed as an important strategy to deliver drugs. These lipid nanoparticles modify drug release, body distribution and kinetics of associated drugs. Other applications of SLNs are tissue/cell targeting of drugs and reduction of unwanted side effects by controlled release. This paper reviews the production techniques, ingredients employed and various applications, also having consideration on various aspects and benefits of solid lipid nanoparticles as colloidal drug carriers.Keywords: Colloidal Drug Carriers, Nanoparticles, Drug Targeting, Biodistributio

In vitro physicochemical characterization of nanocarriers: a road to optimization

Today's drug delivery scientists and pharmaceutical technologists own unprecedented variety of characterization techniques at their disposal not only to assign precise numerical values to the particle parameters but also to probe their developmental phases as well as their internal environment. Therefore, mechanistic understanding of structure-function relationships of nanotherapeutic systems seems to be a dynamic avowal considering the optimization of final nanoformulation system intended for biodistribution and targeting. This chapter aims to decipher the key in vitro physicochemical parameters in dry state, liquid state, as well as in both dry and liquid states, with the perspective of nanoparticle technology, and the diverse physical and experimental means in which these parameters can be demarcated. Further, an attempt has been made to introduce some best suited specialized techniques that enable to expand the accessible range of information to gain deeper insights into specific nanoplatform properties

In vitro physicochemical characterization of nanocarriers: a road to optimization

Today's drug delivery scientists and pharmaceutical technologists own unprecedented variety of characterization techniques at their disposal not only to assign precise numerical values to the particle parameters but also to probe their developmental phases as well as their internal environment. Therefore, mechanistic understanding of structure-function relationships of nanotherapeutic systems seems to be a dynamic avowal considering the optimization of final nanoformulation system intended for biodistribution and targeting. This chapter aims to decipher the key in vitro physicochemical parameters in dry state, liquid state, as well as in both dry and liquid states, with the perspective of nanoparticle technology, and the diverse physical and experimental means in which these parameters can be demarcated. Further, an attempt has been made to introduce some best suited specialized techniques that enable to expand the accessible range of information to gain deeper insights into specific nanoplatform properties