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There is a surge in the use of aluminium in manufacturing industries. This hascaused the need of study of different aluminium joints for assembling the biggerstructures. Most commonly used joining methods are resistance spot welding (RSW),friction stir welding (FSR), and self-piercing riveting. However, each joining processhas their own limitation. RSW is relatively hard to form in aluminum due to theformation of aluminum oxide layer during the welding process. Also, the window ofoperation is extremely short due to conductive nature of aluminum so special skillsoperator are required. FSR welding requires proper fit-up and a high clamping forceto clamp the workpiece against the axial force generated during this welding. Self-piercing riveting requires a die to form the joint interlocking. Different die designs arerequired to obtain the desired strength of the joint which makes this process difficult.Because of these limitations, different aluminum joining methods are in existence foreach industry accordingly to their own unique design constraints.Hence, in this research, detailed study of existing joining methods, along with theirlimitations is carried out. And finally, two new joining techniques; connectors withprotrusions, and threaded screw, are proposed. These joint forming techniques aresimple and do not require complex tools and fixtures. The connectors with protrusionjoint consists of many tiny protrusions arranged in an array on the connector plate.In this experiment, a rectangular connector and pointed tip protrusion is used. Thearrangement of connectors and protrusions are then pressed into aluminum to formthe joint. The shape of the connectors can be altered as per the need. This typeof joint are easy to form, no die is required, surface impurities will not affect thestrength of the joint, fit-up will not be any issue, and also can be used in angularalignment by just changing the connector plates design. The experimental researchwith the simulation was carried out for this joint. The simulation shows that thedeformed aluminum can be pushed back into the trunk of protrusions forming a densestructure. Tensile-shear test is conducted experimentally and average load carried byeach protrusion was found to be 534 N. This value shows that the protrusion wasunder combined tensile and shear loading. This was then verified by metallographicexamination of the fractured surface. The test also shows that the fracture wasinitiated under shear loading and final rupture was under tensile loading. For thesecond method, threaded screw joint, two-sided screw joint is used for aluminiumjoining. The orientation of threads on the screw are opposite in nature. Oppositeorientation of thread produces the turning effect which ease the piercing of metal.This joint forming process is easier compared to other joining methods and is mainlyapplicable for thick aluminum sheet joining. In the threaded screw joint, analyticalstudy was done to calculate total torque produced and the factors that affect thetorque. The torque depends on three factors: radius of thread, angle of revolutionand slope of thread surface. The finding of this research shows that protrusions withconnectors and threaded screw have potential implementation in the aluminum sheetmetal industry, commercial vehicle, and appliance manufacturing.

Cellular edge features have been widely studied in recent years due to the interest in cell motility in normal and cancerous cells. Cues from cell interactions with the extracellular environment lead to overall cytoskeletal remodeling and consequently shape changes. The factors that determine the shape of a cell include actin polymerization, myosin II contraction and focal contacts (FCs). Actin based structures like lamellipodia (broad protrusions), ruffles (vertical protrusions) and filopodia (elongated, tapering protrusions) are the major protrusion types described in the scientific literature. However, their subjective classification is a problem when trying to understand mechanisms of protrusion formation in different cell types. The present study makes use of a previously determined computerized morphometric classification technique to distinguish features other than lamellipodia in 1000W rat tracheal epithelial cells. Some of the features identified through previous studies were factor 4, factor 5, factor 7 and factor 16. The aim of the present study was to explore the role of some of the structural components leading to the formation of a protrusion, particularly to a feature defined as factor 7. Integrated morphometry analysis with MetaMorph software was used to study the FC characteristics, while a geographical information system (GIS) software was used to study the FC orientation with respect to a protrusive feature. Small FCs favored factor 7 feature formation. High factor 7 values were observed when the class of FCs without actin became narrower. Paradoxically, where anchored actin cables on FCs showed a positive correlation with factor 7, the inner radius and width of the FC were the only elevated variables. The results suggested that certain populations of FCs with actin, which were narrow but varied in orientation, are important for factor 7 feature formation. It was observed that the most robust FCs with actin association were related to factor 5 values. The values of both factors 4 and 5 tended to increase with greater elongation of the FCs. FCs without actin cables affected the values of factor 4 and 5 to approximately the same extent. Factor 16 showed no correlations with any dimensioned or shape variable. Actin polymerization and myosin dependence in relationship to protrusions were studied with the aid of cytochalasins and myosin inhibitors, respectively. Cytochalasins inhibited ruffles and stress fibers but surprisingly enhanced factor 7 protrusions. Blebbistatin, SPC 16524, and H1152p, a Rho-kinase (ROCK) inhibitor, showed no ability to inhibit factor 7 features suggesting that myosin II was inessential to the features. The current study suggests that factor 7 feature resembles a pseudopodial feature enhanced by a Rho inhibitory p160/ROCK/p38 mitogen activated protein kinase signal transduction pathway in breast cancer invasiveness. Four models consistent with results were proposed for factor 7 formation. The activity of a minus-end directed motor was proposed in models II, III and IV, and no myosin function at all in model I. All the models ruled out myosin II activity, since the involvement of myosin II would require a contraction of stress fibers, a situation unlikely to generate a protrusion. Hence, the involvement of a minus-end directed motor is more probable. However, further data is required to rigorously test models II, III and IV. Since, model I, on the other hand was proposed to have no myosin activity, it still holds ground. The present study has enabled the identification of features that might aid as a tool in distinguishing normal and cancer cell populations. Disagreement with some aspects of protrusion formation suggests that not all protrusions are formed in the same manner and are under differential regulation. The study encourages the need to abandon subjective classifications of cellular edge features. There is certainly a need to demarcate different protrusion types by a rigorous classification technique to understand mechanisms underlying their formation. A definite understanding of protrusion formation would indeed aid in developing therapeutic approaches to the cancer disease.