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Magnetorheological Elastomers (MRE) endure a change in mechanical properties with the application of an externally applied magnetic field. It consists of an elastomeric matrix reinforced with ferromagnetic powdered particles. This paper focuses on the investigation of viscoelastic properties of Room Temperature Vulcanized (RTV) silicone based isotropic MRE in sandwich beam configuration by varying the volume percentage of Carbonyl Iron Powdered (CIP) reinforcement. Viscoelastic properties of the MRE core material were calculated by following the ASTM E756-05 standard. The magnetic field was applied by employing a Halbach array which was numerically analyzed using Finite Element Method Magnetics (FEMM). The magnetic field was varied up to 0.15 T. Loss factor and shear modulus were found to be strongly influenced by the percentage content of CIP. The loss factor and shear modulus of 30% MRE at 0.15 T were higher than other tested samples. The variation of natural frequency with respect to the addition of CIP was validated numerically using Modal analysis conducted in Hyperworks.

Researchers are trying to find an alternative to the conventional methods of treatment for various pain associated ailments. Patients prefer pain killer as an immediate solution which is proven to have adverse reactions. Since vibroacoustic sound therapy has shown to have relieving effect on different forms of pain, the goal of the study was to find impact of the same using β-endorphin as biomarker, as this could be non-invasive protocol for dental pain management in the future. As a pilot project, 9 subjects of 20-40 years, clinically diagnosed with acute pulpal pain were considered and exposed to 3 frequency groups (low, moderate and high). Impact of vibroacoustic therapy was clinically evaluated by analyzing human salivary β-endorphin using Elisa kit and pain rated by the patients through a numeric rating scale. Statistical analysis performed showed that there is no significant difference for the entire population (P=0.0526), in (P= 0.3618, 0.8264, 0.0671) and between (P=0.4637) the study groups. It would be misleading to take inference due to the small sample size and other observations made.

Introduction: Obesity is a lifestyle disease that is becoming prevalent nowadays and is associated with a surplus in energy balance related to lipid metabolism, inflammation and hypoxic condition, resulting in maladaptive adipose tissue expansion. This study used the publicly available gene dataset to identify a small subset of important genes for diagnostics or as potential targets for therapeutics. Methods: Chemometric analyses by principal component analysis (PCA), random forest (RF), and genetic algorithm (GA) were used to identify 50 genes that differentiate adipose samples from high-fat diet- and normal diet-fed mice. The first 30 important genes were studied for classifying the samples using six different classification techniques. Gene ontology (GO), pathway analysis, and protein-protein interaction studies on the 50 selected genes were subsequently done to identify important functional genes. Finally, gene regulatory effects by microRNA were assessed to confirm the genes’ potential as targets for new therapeutic drugs. Results: The genes identified by RF are best for differentiating the samples, followed by PCA, with the least predictability shown by genes chosen by GA. However, PCA identified more genes with functional importance, such as the hub genes ATP5a1 and Apoa1. ATP5a1 is the main hub gene, whereas Apoa1 is involved in cholesterol metabolism. Vapa and Npc2 are crosstalk genes that link both of these main genes and could be targeted for therapeutic drug design. Conclusion: The combination of different chemometric techniques and functional analysis of genes could be used to select for a small number of genes which could serve as more suitable diagnostic or therapeutic targets.

Aging is an inevitable, natural process that reduces the functionality of the human body over time. Many tasks become too difficult to handle and the body barely hangs on. One such task is the mobility for the geriatric society. People from that age group usually find it hard to go from place to place or will have to depend on someone else for assistance. The purpose of this research is to improve the quality of life for the senior citizens. The research focuses on the design of such a robotic wheelchair which incorporates everything from hardware, software to sensor technology, computer processing and power distribution. When the senior citizen wishes to sit, they will perform a pose from a set of specified poses that elicits a response from the wheelchair in the form of forward movement making it easy for them to be seated. Before propulsion, the distance between the user and the wheelchair is calculated and recorded. While in motion, the wheelchair checks for any obstacles on its path to the user using a simple algorithm incorporating the previously calculated distance. Upon reaching the user, the wheelchair is set to alert the user by the sounding of a buzzer. In the case an obstacle is detected, the wheelchair is set to alert the user in a way that is different as compared to that of alerting the user upon successfully traversing the distance. During the experimentation phase, the wheelchair is triggered and reacts appropriately as and when the poses are performed. The Buzzer is also activated as per the case of either traversing the complete distance or encountering an obstacle. Results from the performance testing demonstrate its functionality as a possible care-giving solution to the senior citizens.

In this research, the results of different weight percentage of glass fiber (30, 40 & 50), cement (0, 3 & 6) and polyester resin (70, 60 & 50), on the properties of glass fiber-cement-polyester composites are investigated. The specimens are prepared by hand lay-up technique. All the specimens are tested for tensile and flexural strength as per ASTM standards. Results showed that escalation in glass fiber wt.% improved the tensile strength (by 9% at 40 wt.% and 17% at 50 wt.%) and flexural strength (by 10% at 40 wt.% and 16.5% at 50 wt.%). Whereas an increase in cement weight percentage decreases tensile strength and increases flexural strength. The failure of the sample is due to glass fiber pull out and rupture of the matrix, under tensile load.

In the present work efforts are made to confirm the presence of actual weight percentage of reinforcements and its effect on aluminium alloy composites during stir casting technique. Two types of reinforcements, such as Silicon carbide and Boron carbide, were used by varying weight to manufacture Al6061 composites. The manufactured composites after stir casting show uniform distribution of hardness on the entire cross-section measured from top to bottom. The dissolved composites during the acid solubility test show approximately 95% of reinforcements present in the aluminium composites. Presence of reinforcements and quantity play a very important role to augment the properties of aluminium alloy by altering the microstructure during solidification and induces strain energy in the metallic matrix alloy. Almost 50–80% increase in hardness and 40–50% increase in tensile strength were observed in the as-cast composites as compared to aluminium alloy. Uniform distribution of reinforcements and hardness distribution on the entire cross-section clearly reveals that stir casting is an effective method for manufacturing aluminium composites.

Permo-Triassic formations in Mandapetta field from eastern onshore, India possesses historical drilling challenges in terms of wellbore instability, non-productive time and poor hole condition in deep higher stressed formations. Lack of acquiring reliable log data and problems in recovering good quality cores present difficulties in proper formation evaluation and zone selection for testing. Historical well test results in target K-Formation has been not encouraging despite good gas shows during drilling. Estimated formation pressure gradient ranges 1.45sg-1.52sg. Layered shale with coal and tight sandstone in same open hole section pose risks of mud losses and poor cement job. Present study highlights the workflow adopted to improve drilling and completion in open hole section of more than 1000 m with varying lithology being drilled successfully. Advanced 3D anisotropic acoustic measurements acquired are used to estimate anisotropic elastic properties (vertical and horizontal Young's modulus and Poisson's ratio) in the overlying shales. Horizontal tectonics has been determined across stress induced anisotropic layers. This approach provides better understanding of formations and stress distribution. Thomsen Gamma values range 0.1 to 0.4 in shale layers of overburden formations. In order to minimize uncertainty in 8.5inch section while drilling, advanced logs were acquired in 12.25inch hole section to estimate tectonics at well location while constraining ratio of horizontal to vertical Young's modulus and Poisson Ratio in shale layers based on Thomsen Gamma and clay volume. Analysis suggested typical VTI anisotropy of 15%-20% in shale layers. Inverted direct horizontal strain parameters at well location suggested the ratio of maximum to minimum horizontal stress to vary 1.15-1.23. Mud weight used while drilling 8.5inch section ranged 1.49sg1.52sg against the recommended mud weight of 1.50sg-1.52sg while pumping sealing agents to prevent mud losses in coal layers. Flow rate was maintained on lower values to minimize ECD values. Hole condition improved significantly with no issues in logging. Post-drill anisotropic rock mechanics model suggested good quality sandstone in target source formation with usual conventional reservoir in shallower formation. Zone was selected based on permeability, breakdown and completion quality for perforations. Analysis of high-quality sonic slowness helped to identify possible gas reservoir in laminated source rock. There was stress contrast of 2000psi-2500psi among reservoir layers and shale stress barriers. Implemented workflow and successful execution helped to drill the well 5 days earlier than plan with no major drilling incidents. Successful core recovery for Shale Gas evaluation was also possible due to better wellbore quality. Initial testing of K-Formation produced gas with significant improved flow rate by 150% without any stimulation for the 1st time in the history of the field.

Nicotine (C10 H14 N2) exists in all parts of the plant but notably in the leaves. Nicotiana tabacum, or cultivated tobacco, is an annually grown herbaceous plant of the Nicotiana genus. In this study a rapid and sensitive evaluation of Nicotine by Thin Layer Chromatography is carried out.