A Study on Principal Component Analysis over Wireless Channel

Applications in many fields such as the internet of things (IoT), stock market, image compression, food adulteration, wireless physical layer key generation, etc. are becoming progressively complex due to a large number of users and increment in their usage. Data obtained by these applications are in huge amount creating a high computational cost. Further, it is difficult to handle and analyze it. To deal with such problems, dimensionality reduction techniques are used and one of the dimensionality reduction techniques is the Principal Component Analysis (PCA). In this paper, PCA is applied over a wireless Rician channel with AWGN at different SNR. It is concluded that the information content is more in less number of principal components with samples at higher SNR. It is also observed that the different combinations of several groups and elements in the sample space provide a different cumulative percentage of information

Stability of vitamin C in drumstick leaf

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Recognising the regenerative impacts of Canadian women tourism social entrepreneurs through a feminist ethic of care lens

Purpose – The overarching aim of this project is to understand the role women tourism social entrepreneurs (TSEs) play in contributing to regenerative practices in Canada. Design/methodology/approach – Semi-structured interviews were carried out with women food TSEs with snowball sampling. This paper challenges the assumption that the masculine experience is the human experience. Accordingly, this research is informed by a feminist ethic of care lens to recognise the important role of Canadian women TSEs. Methodologically, the authors employed the strategies of a constructivist grounded theory to guide the analysis (Charmaz, 2011). This process involved carefully engaging in a close line by line reading of the transcripts, developing codes based on the authors’ dealings with the data including summarising, synthesising and sorting the data (Charmaz, 2011). Findings – The analysis revealed three categories: (1) Adopting a regenerative mindset and enhancing well-being, (2) Supporting the consumption of real food and (3) Educating communities for regenerative and just futures. The analysis revealed the importance of women TSEs in adopting a regenerative and caring mindset to enhance the well-being of their communities and beyond. Research limitations/implications – The study focusses on the learnings from 11 entrepreneurs from Canada. There is a scope to expand the discussion with more interviews. The impact of this pandemic on the small businesses resulted in affecting the researchers’ participation by presenting some unique challenges in participant recruitment. Maybe the studies in the near future will focus on grounding the research papers based on other sexual orientations and indigenous social entrepreneurs. Practical implications – The authors hope future studies centre diversity and attend to the role of women in their communities to better under the diverse contributions. The work presented here is part of a broader study on the role and impact of women TSEs and so only reveals the tip of the Canadian iceberg. Forthcoming studies will attend to some of the gender-specific barriers faced by women TSEs and the supports required particularly in the wake of COVID-19. The authors hope other scholars continue to build on this work, adopting feminist approaches to enhance our understanding of the role women play in contributing to just, caring and regenerative futures. Social implications – Contributing to Higgins-Desbiolles and Monga's (2021) in-depth case study using an ethic of care to examine an Australian events business supporting homeless individuals, the analysis of the 11 in-depth interviews with Canadian TSE provides evidence of alternative ways women are delivering social value. Using an ethic of care lens has elicited the impacts created by the informants and the ripple effects particularly in light of regenerative practices which are crucial in the tourism sector as borders and destinations reopen to tourism as noted by Ateljevic (2020). Originality/value – There are few studies in the tourism social entrepreneurship literature that recognise the agency and centres the vocies of women. Kimbu and Ngoasong (2016) made a call for more research to understand how women engage in social entrepreneurial activities and benefit their local communities. There are limited analyses on regenerative tourism in practice in the scholarly literature. To respond to this gap the authors examine the regenerative practices of women TSEs in Canada

The Putative RNA Helicase HELZ Promotes Cell Proliferation, Translation Initiation and Ribosomal Protein S6 Phosphorylation

The hypoxia–inducible transcription factor (HIF) is a key component of the cellular adaptation mechanisms to hypoxic conditions. HIFα subunits are degraded by prolyl-4-hydroxylase domain (PHD) enzyme-dependent prolyl-4-hydroxylation of LxxLAP motifs that confer oxygen-dependent proteolytic degradation. Interestingly, only three non-HIFα proteins contain two conserved LxxLAP motifs, including the putative RNA helicase with a zinc finger domain HELZ. However, HELZ proteolytic regulation was found to be oxygen-independent, supporting the notion that a LxxLAP sequence motif alone is not sufficient for oxygen-dependent protein destruction. Since biochemical pathways involving RNA often require RNA helicases to modulate RNA structure and activity, we used luciferase reporter gene constructs and metabolic labeling to demonstrate that HELZ overexpression activates global protein translation whereas RNA-interference mediated HELZ suppression had the opposite effect. Although HELZ interacted with the poly(A)-binding protein (PABP) via its PAM2 motif, PABP was dispensable for HELZ function in protein translation. Importantly, downregulation of HELZ reduced translational initiation, resulting in the disassembly of polysomes, in a reduction of cell proliferation and hypophosphorylation of ribosomal protein S6

Alginates along the filament of the brown alga Ectocarpus help cells cope with stress.

Ectocarpus is a filamentous brown alga, which cell wall is composed mainly of alginates and fucans (80%), two non-crystalline polysaccharide classes. Alginates are linear chains of epimers of 1,4-linked uronic acids, β-D-mannuronic acid (M) and α-L-guluronic acid (G). Previous physico-chemical studies showed that G-rich alginate gels are stiffer than M-rich alginate gels when prepared in vitro with calcium. In order to assess the possible role of alginates in Ectocarpus, we first immunolocalised M-rich or G-rich alginates using specific monoclonal antibodies along the filament. As a second step, we calculated the tensile stress experienced by the cell wall along the filament, and varied it with hypertonic or hypotonic solutions. As a third step, we measured the stiffness of the cell along the filament, using cell deformation measurements and atomic force microscopy. Overlapping of the three sets of data allowed to show that alginates co-localise with the stiffest and most stressed areas of the filament, namely the dome of the apical cell and the shanks of the central round cells. In addition, no major distinction between M-rich and G-rich alginate spatial patterns could be observed. Altogether, these results support that both M-rich and G-rich alginates play similar roles in stiffening the cell wall where the tensile stress is high and exposes cells to bursting, and that these roles are independent from cell growth and differentiation

Decreased expression of miR-29 family associated with autoimmune myasthenia gravis.

BACKGROUND: Myasthenia gravis (MG) is a rare autoimmune disease mainly mediated by autoantibodies against the acetylcholine receptor (AChR) at the neuromuscular junction. The thymus is the effector organ, and its removal alleviates the symptoms of the disease. In the early-onset form of MG, the thymus displays functional and morphological abnormalities such as B cell infiltration leading to follicular hyperplasia, and the production of AChR antibodies. Type-I interferon (IFN-I), especially IFN-β, is the orchestrator of thymic changes observed in MG. As Dicer and miR-29 subtypes play a role in modulating the IFN-I signalization in mouse thymus, we investigated their expression in MG thymus. METHODS: The expression of DICER and miR-29 subtypes were thoroughly investigated by RT-PCR in human control and MG thymuses, and in thymic epithelial cells (TECs). Using miR-29a/b-1-deficient mice, with lower miR-29a/b-1 expression, we investigated their susceptibility to experimental autoimmune MG (EAMG) as compared to wild-type mice. RESULTS: DICER mRNA and all miR-29 subtypes were down-regulated in the thymus of MG patients and DICER expression was correlated with the lower expression of miR-29a-3p. A decreased expression of miR-29 subtypes was similarly observed in MG TECs; a decrease also induced in TECs upon IFN-β treatment. We demonstrated that miR-29a/b-1-deficient mice were more susceptible to EAMG without higher levels of anti-AChR IgG subtypes. In the thymus, if no B cell infiltration was observed, an increased expression of Ifn-β associated with Baff expression and the differentiation of Th17 cells associated with increased expression of Il-6, Il-17a and Il-21 and decreased Tgf-β1 mRNA were demonstrated in miR-29a/b-1-deficient EAMG mice. CONCLUSIONS: It is not clear if the decreased expression of miR-29 subtypes in human MG is a consequence or a causative factor of thymic inflammation. However, our results from the EAMG mouse model indicated that a reduction in miR-29a/b1 may contribute to the pathophysiological process involved in MG by favoring the increased expression of IFN-β and the emergence of pro-inflammatory Th17 cells

Use of Toll-Like Receptor Agonists to Induce Ectopic Lymphoid Structures in Myasthenia Gravis Mouse Models

Myasthenia gravis (MG) is an autoimmune disease mediated by autoantibodies against the acetylcholine receptor (AChR) at the neuromuscular junction. MG symptoms are characterized by muscle weaknesses. The thymus of MG patients is very often abnormal and possesses all the characteristics of tertiary lymphoid organs such as neoangiogenesis processes, overexpression of inflammatory cytokines and chemokines, and infiltration of B lymphocytes leading to ectopic germinal center (GC) development. We previously demonstrated that injections of mice with polyinosinic–polycytidylic acid [Poly(I:C)], a synthetic double-stranded RNA mimicking viral infection, induce thymic changes and trigger MG symptoms. Upon Poly(I:C) injections, we observed increased thymic expressions of α-AChR, interferon-β and chemokines such as CXCL13 and CCL21 leading to B-cell recruitment. However, these changes were only transient. In order to develop an experimental MG model associated with thymic GCs, we used Poly(I:C) in the classical experimental autoimmune MG model induced by immunizations with purified AChR emulsified in complete Freund’s adjuvant. We observed that Poly(I:C) strongly favored the development of MG as almost all mice displayed MG symptoms. Nevertheless, we did not observe any ectopic GC development. We next challenged mice with Poly(I:C) together with other toll-like receptor (TLR) agonists known to be involved in GC development and that are overexpressed in MG thymuses. Imiquimod and CpG oligodeoxynucleotides that activate TLR7 and TLR9, respectively, did not induce thymic changes. In contrast, lipopolysaccharide that activates TLR4 potentiated Poly(I:C) effects and induced a significant expression of CXCL13 mRNA in the thymus associated with a higher recruitment of B cells that induced over time thymic B-lymphoid structures. Altogether, these data suggest that tertiary lymphoid genesis in MG thymus could result from a combined activation of TLR signaling pathways

SUMOylation of nuclear actin

Actin, a major component of the cytoplasm, is also abundant in the nucleus. Nuclear actin is involved in a variety of nuclear processes including transcription, chromatin remodeling, and intranuclear transport. Nevertheless, the regulation of nuclear actin by posttranslational modifications has not been investigated. We now show that nuclear actin is modified by SUMO2 and SUMO3 and that computational modeling and site-directed mutagenesis identified K68 and K284 as critical sites for SUMOylating actin. We also present a model for the actin–SUMO complex and show that SUMOylation is required for the nuclear localization of actin