Construction Procurement: Modelling Bidders’ Learning in Recurrent Bidding

Construction remains a significant area of public expenditure. An understanding of the process of changes in construction pricing, and how the process can be manipulated through the release of bidding feedback information is vital, in order to best design clients’ procurement policies. This paper aims to statistically model inexperienced individual bidders’ learning in recurrent bidding under partial and full information feedback conditions. Using an experimental dataset, the developed linear mixed model contains three predictor variables, namely: time factor, information feedback conditions, and bidding success rate in the preceding round. The results show nonlinearity and curvature in the bidders’ learning curves. They are generally less competitive in time periods after a winning bid with lower average bids submitted by those subjected to full information feedback condition. In addition, the model has captured the existence of heterogeneity across bidders with individual-specific parameter estimates that demonstrate the uniqueness of individual bidders’ learning curves in recurrent bidding. The findings advocate for adequate bidding feedback information in clients’ procurement design to facilitate learning among contractors, which may in turn lead to increased competitiveness in their bids

Crosstalk between circadian rhythms and the microbiota

Circadian rhythms influence daily molecular oscillations in gene/protein expression and aspects of biology and physiology, including behaviour, body temperature and sleep–wake cycles. These circadian rhythms have been associated with a number of metabolic, immune and microbial changes that correlate with health and susceptibility to disease, including infection. While light is the main inducer of circadian rhythms, other factors, including the microbiota, can have important effects on peripheral rhythms. The microbiota have been of significant interest to many investigators over the past decade, with the development of molecular techniques to identify large numbers of species and their function. These studies have shown microbial associations with disease susceptibility, and some of these have demonstrated that alterations in microbiota cause disease. Microbial circadian oscillations impact host metabolism and immunity directly and indirectly. Interestingly, microbial oscillations also regulate host circadian rhythms, and the host circadian rhythms in turn modulate microbial composition. Thus, it is of considerable interest and importance to understand the crosstalk between circadian rhythms and microbiota and especially the microbial influences on the host. In this review, we aim to discuss the role of circadian microbial oscillations and how they influence host immunity. In addition, we discuss how host circadian rhythms can also modulate microbial rhythms. We also discuss potential connections between microbes and circadian rhythms and how these may be used therapeutically to maximize clinical success

Complications of Cosmetic Botulinum Toxin A Injections to the Upper Face: A Systematic Review and Meta-Analysis

BACKGROUND: Botulinum toxin A (BoNT-A) injections are a popular non-surgical procedure for facial rejuvenation. Its increase in popularity and utilization is met with limited regulations, potentially posing a significant risk to patient safety and public health. OBJECTIVES: The authors sought to assess the safety profile of cosmetic glabellar and forehead BoNT-A injections and evaluate BoNT-A type on complication rate. METHODS: A systematic search of MEDLINE and EMBASE was performed for studies reporting complications after cosmetic BoNT-A in the glabellar or in the forehead region in the glabellar or in the forehead region. A random effects meta-analysis was carried out to assess complication rate. Where there were sufficient randomized-controlled trials, a network meta-analysis was performed. RESULTS: Of 556 identified articles, 24 were included in the final quantitative analysis, with 4268 BoNT-A injection sessions and 1234 placebos. Frequently observed treatment-related complications in the BoNT-A intervention group included headache, local skin reactions, and facial neuromuscular symptoms. The overall BoNT-A complication rate was 16%. The odds ratio of developing complications from abobotulinum toxin injections compared with placebo was 1.62 (1.15, 2.27; P > 0.05) and that from onabotulinum toxin injections compared with placebo was 1.34 (0.52, 3.48; P > 0.05). In 30% of the studies, the injectors were doctors, whereas the training status of the practitioner was not reported in the remaining 70%. CONCLUSIONS: Cosmetic BoNT-A injections in the glabellar and forehead region appear to be safe, and most complications are mild and transient. Nevertheless, the literature demonstrates heterogeneous reporting of complications and a lack of consistency of the definition of treatment-related complications. LEVEL OF EVIDENCE: 2

Physico-chemical studies on solutions of synthetic non-ionic detergents

This thesis deals with an investigation into the properties of aqueous solutions of non-ionic detergents of the polyoxyethylene mono-alkyl ether clans, and comprises of an introductory and an experimental section, part I and part II respectively. Part I contains a review of previous work on the synthesis and purification of homogeneous non-ionic detergents and on their solution properties. The theoretical basis of micelle formation is then treated and a section is devoted to the structure and strozWring of waters as this is an important factor in micelle formation. Considerable interest has recently been shown in the thermodynamics of micellisation of non-ionic detergents, and the work done to date on this topic is discussed. The penulmate section of the Introduction deals with aqueous non-electrolyte solution with particular reference to hydration and its effect on solute activity concentration relationships. The theory of the techniques used in the investigation (surface tension, light-scattering, viscosity and vapour pressure techniques) is dealt with briefly, and concludes part 1.This thesis deals with an investigation into the properties of aqueous solutions of non-ionic detergents of the polyoxyethylene mono-alkyl ether clans, and comprises of an introductory and an experimental section, part I and part II respectively. Part I contains a review of previous work on the synthesis and purification of homogeneous non-ionic detergents and on their solution properties. The theoretical basis of micelle formation is then treated and a section is devoted to the structure and stroring of waters as this is an important factor in micelle formation. Considerable interest has recently been shown in the thermodynamics of micellisation of non-ionic detergents, and the work done to date on this topic is discussed. The penulmate section of the Introduction deals with aqueous non-electrolyte solution with particular reference to hydration and its effect on solute activity concentration relationships. The theory of the techniques used in the investigation (surface tension, 1ight-scatteriDg, viscosity and vapour pressure techniques) is dealt with briefly, and concludes part 1. The effect of branching the hydrocarbon chain of non-ionic detergents was studied by synthesising a new series of branched-hydrocarbon, chain compounds of general formula, R20CH0CH2(OCH2(H2)n0H with n = 6 or 9 and R 7-1 Olin 9 C2H5D nc-C3H7p WA1/4110 0 Three straight chain compounds were also prepared for comparative studies, these being CH3(CH2)(OCH4H2)110H with = 1. 3 and 5 and n = 6. The surface chemistry of these compounds in aqueous solution was studied at three temperatures. The temperature variation of the critical micelle concentration yielded the enthalpies and entropies of mieellisation by the use of an equation of the Clausius-Clapeyron type. High critical micelle concentrations were evident in some of the systems, and this afforded an opportunity of studying ;ire-t icellar behaviour. Viscosity and vapour pressure measurements gave an indication or the hydration of the detergent monomers and of the polymethylene glycols. Viscosity measurements on micellar solutions yielded hydration values for the micelles, and an increase in hydration of the glycol portion of the monomers was indicated on micelle forwtion. The positive entropy values may be explained by the loss of water structure around the alkyl chains ao they enter the micelleo. Micellar sizes and aggregation numbers were obtained by light-scattering, but the smallness of the micelles precluded any inference am to their shape being drawn from the data. it was concluded, however, that the micelles were in general, symmetrical but for those formed by the detergent, (04H9)20H.GR(0012CH2)6011 which, on interpretation of viscosity measurements and Hugginsl constants,were assumed to become asymmetric as the temperature of the system was raised. Vapour pressure stadies on aqueous solutions of three glycols ( with 6 9 and 12 ethylene oxide mut) showed a negative deviation from Raohlt,e Law, interpmtable in the caul of the first two glycols on the basis of hydration. Other explanations of the deviation of solute activity from ideal behaviour were tested and the results discussed. Similar measurements were also made on three detergent gystams. It was shown that the activity of the detergent increased above the critical micelle concentration, in agreement with the behaviour predicted by the Law of Mass Action approach to micelle formation, although at variance with the predictions of the pseudo-phase approach

Facial skin ageing: Key concepts and overview of processes

INTRODUCTION: The face is a cosmetically sensitive region where the process of ageing is most clearly manifested. With increased focus on anti-ageing and longevity, more anti-senescent treatments are being proposed despite limited evidence. This study outlines the pathways and mechanisms underpinning the biological process of ageing in the face. METHODS: Comprehensive searches of MEDLINE, EMBASE, Cochrane Library and CINAHL from inception to 2020. Inclusion criteria included all empirical human research studies specific to facial ageing features, written in the English language. RESULTS: A total of 65 papers met inclusion criteria for analysis. Pathways were subdivided into intrinsic and extrinsic senescence mechanisms. Intrinsic pathways included genetics, generation of reactive oxygen species and hormonal changes. Extrinsic pathways included photoageing and damage to skin layers. The combined intrinsic and extrinsic pathway alterations result in wrinkles, higher laxity, slackness and thinning of the skin. Skin functions such as barrier immune function, wound healing, thermoregulation and sensory function are also impaired. CONCLUSION: The ageing process is unique to the individual and depends on the interplay between an individual's genetics and external environmental factors. Through understanding the molecular and cellular mechanisms, an appreciation of the consequent structural and functional changes can be achieved. Based on this knowledge, further research can focus on how to slow or impede the ageing process and identify specific targets to develop and evolve new treatment strategies

Cultural competency of health-care providers in a Swiss University Hospital: self-assessed cross-cultural skillfulness in a cross-sectional study

Background: As the diversity of the European population evolves, measuring providers’ skillfulness in cross-cultural care and understanding what contextual factors may influence this is increasingly necessary. Given limited information about differences in cultural competency by provider role, we compared cross-cultural skillfulness between physicians and nurses working at a Swiss university hospital. Methods: A survey on cross-cultural care was mailed in November 2010 to front-line providers in Lausanne, Switzerland. This questionnaire included some questions from the previously validated Cross-Cultural Care Survey. We compared physicians’ and nurses’ mean composite scores and proportion of “3-good/4-very good” responses, for nine perceived skillfulness items (4-point Likert-scale) using the validated tool. We used linear regression to examine how provider role (physician vs. nurse) was associated with composite skillfulness scores, adjusting for demographics (gender, non-French dominant language), workplace (time at institution, work-unit “sensitized” to cultural-care), reported cultural-competence training, and cross-cultural care problem-awareness. Results: Of 885 questionnaires, 368 (41.2%) returned the survey: 124 (33.6%) physicians and 244 (66.4%) nurses, reflecting institutional distribution of providers. Physicians had better mean composite scores for perceived skillfulness than nurses (2.7 vs. 2.5, p < 0.005), and significantly higher proportion of “good/very good” responses for 4/9 items. After adjusting for explanatory variables, physicians remained more likely to have higher skillfulness (β = 0.13, p = 0.05). Among all, higher skillfulness was associated with perception/awareness of problems in the following areas: inadequate cross-cultural training (β = 0.14, p = 0.01) and lack of practical experience caring for diverse populations (β = 0.11, p = 0.04). In stratified analyses among physicians alone, having French as a dominant language (β = −0.34, p < 0.005) was negatively correlated with skillfulness. Conclusions: Overall, there is much room for cultural competency improvement among providers. These results support the need for cross-cultural skills training with an inter-professional focus on nurses, education that attunes provider awareness to the local issues in cross-cultural care, and increased diversity efforts in the work force, particularly among physicians

Fighting Ebola with novel spore decontamination technologies for the military

AbstractRecently, global public health organizations such as Doctors without Borders (MSF), the World Health Organization (WHO), Public Health Canada, National Institutes of Health (NIH), and the U.S. government developed and deployed Field Decontamination Kits (FDKs), a novel, lightweight, compact, reusable decontamination technology to sterilize Ebola-contaminated medical devices at remote clinical sites lacking infra-structure in crisis-stricken regions of West Africa (medical waste materials are placed in bags and burned). The basis for effectuating sterilization with FDKs is chlorine dioxide (ClO2) produced from a patented invention developed by researchers at the US Army – Natick Soldier RD&E Center (NSRDEC) and commercialized as a dry mixed-chemical for bacterial spore decontamination. In fact, the NSRDEC research scientists developed an ensemble of ClO2 technologies designed for different applications in decontaminating fresh produce; food contact and handling surfaces; personal protective equipment; textiles used in clothing, uniforms, tents, and shelters; graywater recycling; airplanes; surgical instruments; and hard surfaces in latrines, laundries, and deployable medical facilities. These examples demonstrate the far-reaching impact, adaptability, and versatility of these innovative technologies. We present herein the unique attributes of NSRDEC’s novel decontamination technologies and a Case Study of the development of FDKs that were deployed in West Africa by international public health organizations to sterilize Ebola-contaminated medical equipment. FDKs use bacterial spores as indicators of sterility. We review the properties and structures of spores and the mechanisms of bacterial spore inactivation by ClO2. We also review mechanisms of bacterial spore inactivation by novel, emerging, and established nonthermal technologies for food preservation, such as high pressure processing, irradiation, cold plasma, and chemical sanitizers, using an array of