A Reusable PZT Transducer for Monitoring Initial Hydration and Structural Health of Concrete

During the construction of a concrete structure, strength monitoring is important to ensure the safety of both personnel and the structure. Furthermore, to increase the efficiency of in situ casting or precast of concrete, determining the optimal time of demolding is important for concrete suppliers. Surface bonded lead zirconate titanate (PZT) transducers have been used for damage detection and parameter identification for various engineering structures over the last two decades. In this work, a reusable PZT transducer setup for monitoring initial hydration of concrete and structural health is developed, where a piece of PZT is bonded to an enclosure with two bolts tightened inside the holes drilled in the enclosure. An impedance analyzer is used to acquire the admittance signatures of the PZT. Root mean square deviation (RMSD) is employed to associate the change in concrete strength with changes in the PZT admittance signatures. The results show that the reusable setup is able to effectively monitor the initial hydration of concrete and the structural health. It can also be detached from the concrete for future re-use

The minor house dust mite allergen Der p 13 is a fatty acid binding protein and an activator of a TLR2-mediated innate immune response

Background: The house dust mite (HDM) allergen Der p 13 could be a lipid-binding protein able to activate key innate signaling pathways in the initiation of the allergic response. We investigated the IgE reactivity of recombinant Der p 13 (rDer p 13), its lipid binding activities and its capacity to stimulate airway epithelium cells. Methods: Purified rDer p 13 was characterized by mass spectrometry, circular dichroism, fluorescence-based lipid binding assays and in-silico structural prediction. IgE binding activity and allergenic potential of Der p 13 were examined by ELISA, basophil degranulation assays and in-vitro airway epithelial cell activation assays. Results: Protein modeling and biophysical analysis indicated that Der p 13 adopts a β barrel structure with a predominately apolar pocket representing a potential binding site for hydrophobic ligands. Fluorescent lipid binding assays confirmed that the protein is highly selective for ligands and that it binds a fatty acid with a dissociation constant typical of lipid transporter proteins. The low IgE binding frequency (7%, n= 224) in Thai HDM-allergic patients as well as the limited propensity to activate basophil degranulation classifies Der p 13 as a minor HDM allergen. Nevertheless, the protein with its presumptively associated lipid(s) triggered the production of IL-8 and GM-CSF in respiratory epithelial cells through a TLR2-, MyD88-, NF-kB- and MAPK-dependent signaling pathway. Conclusions: Although a minor allergen, Der p 13 may, through its lipid binding capacity, play a role in the initiation of the HDM allergic response through TLR2 activation

Modelling eggshell maculation

The eggshells of many avian species are characterised by distinctive patterns of maculation, consisting of speckles, spots, blotches or streaks, the spatial-statistical properties of which vary considerably between (and often within) species. Understanding the mechanisms underlying the production of eggshell maculation would enable us to explore the costs and constraints on the evolution of maculation patterns, but as yet this area is surprisingly understudied. Here I present a simple model of eggshell maculation, which is based on the known biology of pigment deposition, and which can produce a range of realistic maculation patterns. In particular, it provides an explanation for previous observations of maculation heterogeneity and diversity, and allows testable predictions to be made regarding maculation patterns, including a possible signalling role

Initial study on microwave technique to find the relationship between attenuation of microwave and thickness of a subject

This paper presents the initial study of microwave tomography in agriculture to investigate the effect of microwave signal on the thickness of a medium. In this project, a pair of antennas is used non-invasively where one of it acts as a transmitter and the other one as a receiver. The investigation was based on the transmission and reception of antennas in a transversal direction while several samples of mediums with different thickness are put between those antennas. The result obtained throughout this initial study had shown that the attenuation of microwave will vary with the diameter of the medium. The information and analysis of the preliminary results can be used as a reference for further investigation on the selected mediu

Microwave tomography application and approaches - a review

The objective of this paper is to review microwave tomography based on its field, application and antennas approaches. Researches on microwave tomography system have been done unceasingly for several decades especially in determine the dielectric properties for the material. Firstly, the dielectric properties and its influencing factors will be briefly described. Besides, although it has the potential to overcome other process tomography system, it still have some drawbacks. So, the general advantages and disadvantages are listed. Next, survey on the application of microwave tomography and type of antennas used will be discussed. Followed by the trend for the future

Prevalence and risk factors to HIV-infection amongst health care workers within public and private health facilities in Cameroon.

Introduction: This study aimed at assessing the prevalence of Human Immunodeficiency Virus (HIV) among health care workers (HCWs) and to evaluate some risks factors for HCWs. Methods: We conducted a cross sectional study amongst HCWs in public and private healthcare facilities within seven regions amongst the 10 found in Cameroon. We collected data from 446 HCWs within 150 healthcare facilities. We used questionnaires for interviews and biological sampling for HIV test. Results: HIV prevalence was 2.61% (95% CI: 1.32% - 4.61%) regardless of gender and age. HCWs in private health facilities were more infected compared to those in public health facilities 5.00% vs 1.40% (p = 0.028); OR = 3.7 (95% CI: 1.01-12.90). HCWs who had never screened for HIV had a high risk of being infected OR = 7.05 (95% CI: 2.05-24.47). 44.62% of HCWs reported to have been victim of an Accidental Exposure to Blood (AEB). Amongst them, 45.80% in public HF versus 32.1% in private HF reported to have received an HIV screening and Post Exposure Prophylaxis following this incident. 4.20% of HCW victim of AEB were HIV positive, and 36.40% of HCWs had appropriate capacity training for HIV patient care. Conclusion: Though the HIV prevalence in HCWs is lower than in the general population 2.61% vs 4.3%, there is a high risk of infection as we observed a relatively high percentage of AEB amongst HCWs with an HIV prevalence of 4.20%. There is thus, a need in strengthening the capacity and provide psychosocial support to HCWs

Modulation of vaccine response by concomitant probiotic administration

Evidence suggests that probiotic bacteria modulate both innate and adaptive immunity in the host, and in some situations can result in reduced severity of common illnesses, such as acute rotavirus infection and respiratory infections. Responses to vaccination are increasingly being used to provide high quality information on the immunomodulatory effects of dietary components in humans. The present review focuses on the effect of probiotic administration upon vaccination response. The majority of studies investigating the impact of probiotics on responses to vaccination have been conducted in healthy adults, and at best they show modest effects of probiotics on serum or salivary IgA titres. Studies in infants and in elderly subjects are very limited, and it is too early to draw any firm conclusions regarding the potential for probiotics to act as adjuvants in vaccination. Although some studies are comparable in terms of duration of the intervention and age and characteristics of the subjects, most differ in terms of the probiotic selected. Further well designed, randomized, placebo-controlled studies are needed to fully understand the immunomodulatory properties of probiotics, whether the effects exerted are strain-dependent and age-dependent, and their clinical relevance in enhancing immune protection following vaccination

Falls efficacy: Extending the understanding of self-efficacy in older adults towards managing falls

Shawn Leng-Hsien Soh - ORCID: 0000-0002-8725-5182 https://orcid.org/0000-0002-8725-5182Janet Thomas - ORCID: 0000-0002-1037-7923 https://orcid.org/0000-0002-1037-7923Judith Lane - ORCID: 0000-0003-0413-8421 https://orcid.org/0000-0003-0413-8421Publisher's accepted article replaced by VoR 2021-09-02Falls efficacy is a widely studied construct. The understanding of falls efficacy has evolved over time. Falls efficacy was initially perceived to be suitably used as a measure of fear of falling. However, further research suggested that falls efficacy and fear of falling are distinct constructs, and therefore, would be inappropriate to be used as a proxy. Instead, some researchers posited that falls efficacy is synonymous with balance confidence. Falls efficacy has been conventionally understood as the perceived ability of individuals to perform activities without losing balance or falling. A recently conducted systematic review by the authors on existing falls efficacy related measures had revealed a fresh perspective of recognising falls efficacy as a perceived ability to manage a threat of a fall. Falls efficacy, with a broadened interpreted construct, relates to the individual’s perceived self-efficacy of performing necessary actions needed in different scenarios, including pre-fall, near-fall, fall-landing and completed fall. The conventional interpretation of falls efficacy needs a rethinking of perspective. An extended understanding of falls efficacy would provide an integral approach towards improving the agency of individual to deal with falls and would enhance person-centred care.https://doi.org/10.22540/JFSF-06-1316pubpub

The house dust mite allergen Der p 5 binds lipid ligands and stimulates airway epithelial cells through a TLR2‐dependent pathway

Background: Protein crystallographic studies suggest that the house dust mite (HDM) allergen Der p 5 potentially interacts with hydrophobic ligands. Der p 5, in association with its ligand(s), might therefore trigger innate immune signalling pathways in the airway epithelium and influence the initiation of the HDM‐allergic response. Objective: We investigated the lipid binding propensities of recombinant (r)Der p 5 and characterized the signalling pathways triggered by the allergen in airway epithelial cells. Methods: rDer p 5 was produced in Pichia pastoris and characterized by mass spectrometry, multi‐angle light scattering and circular dichroism. Its interactions with hydrophobic ligands were investigated in fluorescence‐based lipid binding assays and in‐silico docking simulations. Innate immune signalling pathways triggered by rDer p 5 were investigated in airway epithelial cell activation assays in vitro. Results: Biophysical analysis showed that rDer p 5 was monomeric and adopted a similar α‐helix‐rich fold at both physiological and acidic pH. Spectrofluorimetry experiments showed that rDer p 5 is able to selectively bind lipid ligands, but only under mild acidic pH conditions. Computer‐based docking simulations identified potential binding sites for these ligands. This allergen, with putatively associated lipid(s), triggered the production of IL‐8 in respiratory epithelial cells through a TLR2‐, NF‐kB‐ and MAPK‐dependent signalling pathway. Conclusions and Clinical Relevance: Despite the fact that Der p 5 represents a HDM allergen of intermediate prevalence, our findings regarding its lipid binding and activation of TLR2 indicate that it could participate in the initiation of the HDM‐allergic state

Chemical reactions at the graphitic step-edge: changes in product distribution of catalytic reactions as a tool to explore the environment within carbon nanoreactors

A series of explorative cross-coupling reactions have been developed to investigate the local nanoscale environment around catalytically active Pd(II)complexes encapsulated within hollow graphitised nanofiber (GNF). Two new fullerene-containing and fullerene-free Pd(II)Salen catalysts have been synthesised, and their activity and selectivity towards different substrates has been explored in nanoreactors. The catalysts not only show a significant increase in activity and stability upon heterogenisation at the graphitic step-edges inside the GNF channel, but also exhibit a change in selectivity affected by the confinement which alters the distribution of isomeric products of the reaction. Furthermore, the observed selectivity changes reveal unprecedented details regarding the location and orientation of the catalyst molecules inside the GNF nanoreactor, inaccessible by any spectroscopic or microscopic techniques, thus shedding light on the precise reaction environment inside the molecular catalyst-GNF nanoreactor. Keywords: nanoreactor, catalysis, fullerene, salen, cross-couplin