Unlike conventional materials removal methods, additive manufacturing (AM) is based on a novel materials incremental manufacturing philosophy. Additive manufacturing implies layer by layer shaping and consolidation of powder feedstock to arbitrary configurations, normally using a computer controlled laser. The current development focus of AM is to produce complex shaped functional metallic components, including metals, alloys and metal matrix composites (MMCs), to meet demanding requirements from aerospace, defence, automotive and biomedical industries. Laser sintering (LS), laser melting (LM) and laser metal deposition (LMD) are presently regarded as the three most versatile AM processes. Laser based AM processes generally have a complex non-equilibrium physical and chemical metallurgical nature, which is material and process dependent. The influence of material characteristics and processing conditions on metallurgical mechanisms and resultant microstructural and mechanical properties of AM proc...

Laser additive manufacturing of metallic components: materials, processes and mechanisms

Selective laser melting of iron-based powder

Surface plasmon resonance (SPR) is a label-free detection method which has emerged during the last two decades as a suitable and reliable platform in clinical analysis for biomolecular interactions. The technique makes it possible to measure interactions in real-time with high sensitivity and without the need of labels. This review article discusses a wide range of applications in optical-based sensors using either surface plasmon resonance (SPR) or surface plasmon resonance imaging (SPRI). Here we summarize the principles, provide examples, and illustrate the utility of SPR and SPRI through example applications from the biomedical, proteomics, genomics and bioengineering fields. In addition, SPR signal amplification strategies and surface functionalization are covered in the review.

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Surface Plasmon Resonance: A Versatile Technique for Biosensor Applications

Al-12Si specimens are produced by selective laser melting (SLM) from gas atomized powders. An extremely fine cellular structure is observed with residual free Si along the cellular boundaries. Room temperature tensile tests reveal a remarkable mechanical behavior: the samples show yield and tensile strengths of about 260. MPa and 380. MPa, respectively, along with fracture strain of ~3%. The effect of annealing on microstructure and related tensile properties is examined and the results demonstrate that the mechanical behavior of the Al-12Si SLM samples can be tuned within a wide range of strength and ductility through proper annealing treatment.

Microstructure and mechanical properties of Al-12Si produced by selective laser melting: Effect of heat treatment

Progress on the morphological control of conductive network in conductive polymer composites and the use as electroactive multifunctional materials

The ability of a cell to contract plays an important role in determining the ability of the cell to migrate, proliferate and
associating with other cells. The transduction of the force in soft substrate such as the liquid crystal surface is a method
proposed to study the traction forces of single cells. In this work, finite element method was used to study the compressive
forces induced by the keratinocyte to the liquid crystal surface via the anchorage of focal contacts. The constitutive finite
element model of the liquid crystal-focal contacts was established. The stress and displacement were analyzed using linear
static stress analysis for a quiescent cell. The data for lateral displacements obtained from the experiment were provided as
inputs to develop the model and verified through the output acquired for both simulation and experiment. The simulation
results indicated that the cell compressive stresses were in the range of 14.93 ± 1.9 nN/μm2 per focal contact. Based on the
result obtained, it was suggested to model focal contact-liquid crystal interface with a compressive model that can better
approximate the mechanism observed.

Compressive forces of cell induced longitudinal deformation to the liquid crystal surface

Discovering a new cancer treatment Researchers are becoming more eager to uncover new medicinal compounds from living species. In the UK, CBD has been rising in demand as an alternative therapeutic agent and is used in various medicinal products. CBD, or cannabidiol, is a phytocannabinoid, one of the identified cannabinoids in cannabis plants. It doesn't contain tetrahydrocannabinol (THC), which is a psychoactive ingredient. While electroporation is one of the non-invasive techniques for nonviral delivery systems, such as molecule introduction and molecule transfer in a variety of sizes depending on the parameter chosen. The cell response to CBD compound combined with the electroporation method was the focus of this study. The findings demonstrated a positive response to the antiproliferative properties of cancer cells, and the treatment was further aided by a pulse electric field of 600 V/cm for $30 \mu \mathrm{s}$ with a single pulse. The results showed further decrements in cell viability. This finding may contribute toward cancer treatment as an adjunct alternative anticancer agent.

Study on Cannabidiol and Pulse Electric Field on Breast Cancer Cells

Electroporation (EP) is a method of controlling cell function by using pulses of electrical fields to create pore through a cell membrane and causes other substance around it to be absorbed into the cell. Where this method had been led to a variety of medical applications. While, micro contact printing (μCP) is a quite useful technique for patterning extracellular matrix as an adhesion molecule for cells that works for controlling the cell growth. This study focuses on a comparison of a cancer cell (HeLa cancer cell) cultured on two different type of substrates which is a protein surface and empty surface. In order to see the effect of cell proliferation of cancer cell with protein solution, which is in this experiment we used fibronectin for the protein solution and the preliminary result show a positive respond to the protein solution that act as self-assembled monolayer.

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Investigation of electroporation technique on cell propertiescultured on self-assembled monolayer

There has been much focus on the role of transforming growth factor β (TGFβ) and more spicifically TGFβ3 in wound healing, with a variety of cell types being studied. There is however, little understanding of the actions of TGFβ3 and how this particular isoforms mediates its scarless healing effects. Studying cellular responses to different extracellular matrix proteins enables the identification of candidate integrins that may be up/down regulated in response to such growth factors. In this study, microcontact printing was used to assess the responses of a human keratinocyte cell line (HaCaT cells) to fibronectin, laminin and collagen type I patterned on glass substrates via microcontact printing and how these responses were changed by treatment with TGFβ3. We demonstrate that HaCaT cell alignment to patterned ECM molecules is decreased by treatment with TGFβ3 and that this response is mediated by an increased keratinocyte migration associated with an enhanced deposition of laminin onto the culture substrate.

Transforming growth factor β 3 causes decreased HaCaT cell alignment to extracellular matrix proteins Fibronectin, Laminin and Collagen type I as a result of an enhanced migratory phenotype

Microencapsulation technology had been widely used in biological study, drug delivery, cosmetic and also food industry. Previous methods developed for microencapsulation is complex in terms of their design and handling. A simple micro extruder device with vibration mode was developed to microencapsulate HaCaT cells in calcium alginate capsules at 10 to 60 Hz. The microencapsulated cells proliferated and formed into microtissues. Alginate lyase was applied to remove the microtissues from the encapsulation and for studying the cell adhesion in the microtissues. DAPI and live/dead cell stainings were applied to study the organisation and viability of cells, respectively. Via the nuclei staining, it was found that the distance between cells reduced as the incubation period increased. After 15 days of culture, the cells were viable as indicated by the fluorescence green expression of Calcein-AM. Replating experiment indicated that the cells from the microtissues were able to migrate and has the tendency to form monolayer of cells on the culture flask.

Mansour Youseffi

Papers

Compressive forces of cell induced longitudinal deformation to the liquid crystal surface

Study on Cannabidiol and Pulse Electric Field on Breast Cancer Cells

Investigation of electroporation technique on cell propertiescultured on self-assembled monolayer

Transforming growth factor β 3 causes decreased HaCaT cell alignment to extracellular matrix proteins Fibronectin, Laminin and Collagen type I as a result of an enhanced migratory phenotype

Growth of microtissues in microencapsules formed using microextrusion and vibration