Interferometric Fiber Optic Sensors

Fiber optic interferometers to sense various physical parameters including temperature, strain, pressure, and refractive index have been widely investigated. They can be categorized into four types: Fabry-Perot, Mach-Zehnder, Michelson, and Sagnac. In this paper, each type of interferometric sensor is reviewed in terms of operating principles, fabrication methods, and application fields. Some specific examples of recently reported interferometeric sensor technologies are presented in detail to show their large potential in practical applications. Some of the simple to fabricate but exceedingly effective Fabry-Perot interferometers, implemented in both extrinsic and intrinsic structures, are discussed. Also, a wide variety of Mach-Zehnder and Michelson interferometric sensors based on photonic crystal fibers are introduced along with their remarkable sensing performances. Finally, the simultaneous multi-parameter sensing capability of a pair of long period fiber grating (LPG) is presented in two types of structures; one is the Mach-Zehnder interferometer formed in a double cladding fiber and the other is the highly sensitive Sagnac interferometer cascaded with an LPG pair

Fascin overexpression promotes neoplastic progression in oral squamous cell carcinoma

<p>Abstract</p> <p>Background</p> <p>Fascin is a globular actin cross-linking protein, which plays a major role in forming parallel actin bundles in cell protrusions and is found to be associated with tumor cell invasion and metastasis in various type of cancers including oral squamous cell carcinoma (OSCC). Previously, we have demonstrated that fascin regulates actin polymerization and thereby promotes cell motility in K8-depleted OSCC cells. In the present study we have investigated the role of fascin in tumor progression of OSCC.</p> <p>Methods</p> <p>To understand the role of fascin in OSCC development and/or progression, fascin was overexpressed along with vector control in OSCC derived cells AW13516. The phenotype was studied using wound healing, Boyden chamber, cell adhesion, Hanging drop, soft agar and tumorigenicity assays. Further, fascin expression was examined in human OSCC samples (N = 131) using immunohistochemistry and level of its expression was correlated with clinico-pathological parameters of the patients.</p> <p>Results</p> <p>Fascin overexpression in OSCC derived cells led to significant increase in cell migration, cell invasion and MMP-2 activity. In addition these cells demonstrated increased levels of phosphorylated AKT, ERK1/2 and JNK1/2. Our in vitro results were consistent with correlative studies of fascin expression with the clinico-pathological parameters of the OSCC patients. Fascin expression in OSCC showed statistically significant correlation with increased tumor stage (<it>P </it>= 0.041), increased lymph node metastasis (<it>P </it>= 0.001), less differentiation (<it>P </it>= 0.005), increased recurrence (<it>P </it>= 0.038) and shorter survival (<it>P </it>= 0.004) of the patients.</p> <p>Conclusion</p> <p>In conclusion, our results indicate that fascin promotes tumor progression and activates AKT and MAPK pathways in OSCC-derived cells. Further, our correlative studies of fascin expression in OSCC with clinico-pathological parameters of the patients indicate that fascin may prove to be useful in prognostication and treatment of OSCC.</p

Tacit Knowledge Transfer in Agile Software Development

Background. Software companies make frequent development in their software products to improve their quality. Agile software development (ASD) helps in the rapid delivery of the software product with consistent quality to the customer. Agile Software development shares a lot of characteristics with knowledge-intensive works, and it also needs lot of knowledge from different domains of both human and com- puting domains. Knowledge is defined as a belief of one individual capability for an effective action. Tacit knowledge is a category of the knowledge management which is defined an individuals’ memory, action or beliefs. Moreover, tacit knowledge plays a crucial role in ASD. However, tacit knowledge is hard to transfer among team mem- bers as tacit knowledge is based on an individual experience. Tacit knowledge is not documented for further reference so there is a need to study how efficiently can tacit knowledge is currently being transferred in the industry, what challenges are being faced in tacit knowledge transfer and the mitigation strategies used to overcome the tacit knowledge transfer challenges. Objectives. In this present thesis, we focused on how tacit knowledge is being transferred among team members in agile software development. Objective 1: To identify the current tacit knowledge transfer mechanism in agile software development. Objective 2: To identify challenges in managing tacit knowledge transfer between team members in Agile software development. Objective 3: To explore mitigation strategies to overcome the challenges faced dur- ing tacit knowledge transfer. Methods. In this study, SLR and interviews were implemented to achieve the objective. SLR was used to achieve the first two objectives, and interviews were conducted to achieve all the objectives. Results. From SLR, a total of 21 challenges and 12 transfer mechanisms have been identified whereas, from the interviews, a total of 12 challenges, 8 transfer mecha- nisms, and 7 mitigation strategies have been identified. There were new challenges and transfer mechanisms identified in both research methods. Some of the transfer mechanisms consist of daily scrum calls and day-to-day forums among the teams. Both the research methods’ results indicate that one of the most challenging parts while transferring tacit knowledge is the lack of critical thinking with human orienta- tion. Based on the interviews, some of the mitigation strategies such as regular sprint meetings, and online whiteboarding were considered to overcome the tacit knowledge transfer challenges. Conclusions. Based on the challenges identified from the interview, it is evident that teams working in distributed teams are facing more challenges in transferring tacit knowledge, and tacit knowledge transfer sessions should be recorded to reduce the challenges

Tacit Knowledge Transfer in Agile Software Development

Background. Software companies make frequent development in their software products to improve their quality. Agile software development (ASD) helps in the rapid delivery of the software product with consistent quality to the customer. Agile Software development shares a lot of characteristics with knowledge-intensive works, and it also needs lot of knowledge from different domains of both human and com- puting domains. Knowledge is defined as a belief of one individual capability for an effective action. Tacit knowledge is a category of the knowledge management which is defined an individuals’ memory, action or beliefs. Moreover, tacit knowledge plays a crucial role in ASD. However, tacit knowledge is hard to transfer among team mem- bers as tacit knowledge is based on an individual experience. Tacit knowledge is not documented for further reference so there is a need to study how efficiently can tacit knowledge is currently being transferred in the industry, what challenges are being faced in tacit knowledge transfer and the mitigation strategies used to overcome the tacit knowledge transfer challenges. Objectives. In this present thesis, we focused on how tacit knowledge is being transferred among team members in agile software development. Objective 1: To identify the current tacit knowledge transfer mechanism in agile software development. Objective 2: To identify challenges in managing tacit knowledge transfer between team members in Agile software development. Objective 3: To explore mitigation strategies to overcome the challenges faced dur- ing tacit knowledge transfer. Methods. In this study, SLR and interviews were implemented to achieve the objective. SLR was used to achieve the first two objectives, and interviews were conducted to achieve all the objectives. Results. From SLR, a total of 21 challenges and 12 transfer mechanisms have been identified whereas, from the interviews, a total of 12 challenges, 8 transfer mecha- nisms, and 7 mitigation strategies have been identified. There were new challenges and transfer mechanisms identified in both research methods. Some of the transfer mechanisms consist of daily scrum calls and day-to-day forums among the teams. Both the research methods’ results indicate that one of the most challenging parts while transferring tacit knowledge is the lack of critical thinking with human orienta- tion. Based on the interviews, some of the mitigation strategies such as regular sprint meetings, and online whiteboarding were considered to overcome the tacit knowledge transfer challenges. Conclusions. Based on the challenges identified from the interview, it is evident that teams working in distributed teams are facing more challenges in transferring tacit knowledge, and tacit knowledge transfer sessions should be recorded to reduce the challenges

Solvent-driven isomerization of cis,cis-muconic acid for the production of specialty and performance-advantaged cyclic biobased monomers

The quest for green plastics calls for new routes to aromatic monomers using biomass as a feedstock. Suitable feedstock molecules and conversion pathways have already been identified for several commodity aromatics through retrosynthetic analysis. However, this approach suffers from some limitations as it targets a single molecule at a time. A more impactful approach would be to target bioprivileged molecules that are intermediates to an array of commodity and specialty chemicals along with novel compounds. Muconic acid (MA) has recently been identified as a bioprivileged intermediate as it gives access to valuable aliphatic and cyclic diacid monomers including terephthalic acid (TPA), 1,4-cyclohexanedicarboxylic acid (CHDA), and novel monounsaturated 1,4-cyclohexenedicarboxylic acids (CH1DA, CH2DA). However, accessing these cyclic monomers from MA requires to first isomerize biologically-produced cis,cis-MA to Diels–Alder active trans,trans-MA. A major impediment in this isomerization is the irreversible ring closing of MA to produce lactones. Herein, we demonstrate a green solvent-mediated isomerization using dimethyl sulfoxide and water. The mechanistic understanding achieved here elucidates the role of low concentrations of water in reducing the acidity of the system, thereby preventing the formation of lactones and improving the selectivity to trans,trans-MA from less than 5% to over 85%. Finally, a Diels–Alder reaction with trans,trans-MA is demonstrated with ethylene. The monounsaturated cyclic diacid obtained through this reaction (CH1DA) can be converted in a single step into TPA and CHDA, or can be directly copolymerized with adipic acid and hexamethylenediamine to tailor the thermal and mechanical properties of conventional Nylon 6,6.This article is published as Carraher, Jack M., Prerana Carter, Radhika G. Rao, Michael J. Forrester, Toni Pfennig, Brent H. Shanks, Eric W. Cochran, and Jean-Philippe Tessonnier. "Solvent-driven isomerization of cis, cis-muconic acid for the production of specialty and performance-advantaged cyclic biobased monomers." Green Chemistry 22, no. 19 (2020): 6444-6454. DOI: 10.1039/D0GC02108C. Copyright 2020 The Royal Society of Chemistry. Attribution-NonCommercial 3.0 Unported (CC BY-NC 3.0). Posted with permission

Nanoparticle drug delivery systems in hepatocellular carcinoma: A focus on targeting strategies and therapeutic applications

Hepatocellular carcinoma (HCC) is recognized as a global health issue accounting for millions of deaths every year. Surgery, liver ablation, and embolization therapy are amongst the conventional methods for treatment of HCC. Chemotherapy plays a major role in HCC therapy, however, owing to its conventional pharmacotherapy limitations, it necessitates the development of novel therapeutic strategies. In contrast, nanomedicines for HCC have shown remarkable prospects for solving these complications in HCC owing to their high stability, controlled release, and high drug loading capacity. This review gives an insight into the nano-constructs used for HCC treatment and its active and passive targeting strategies. This review also inculcates the various approaches for targeting the liver cells, its targeting moieties and the conjugation chemistries involved in surface functionalization. A brief description of various therapeutic approaches in the treatment of HCC has also been discussed