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

The Effect of Information Feedback in Construction Bidding

 With the goal to achieve efficiency in bidding competitions, many codes of bidding procedure recommend clients provide contractors with bidding feedback information. Contractors strive to bid competitively via learning based on their experiences in past bidding attempts. The level of bidding feedback information, however, varies across clients. In many cases, clients do not provide feedback or provide insufficient feedback to contractors. Focussing on two information feedback conditions (full and partial), we examine: (i) the changes in bidding trend over time, and (ii) the effects of bidding feedback information on bidders’ competitiveness in bidding. Data were gathered using a bidding experiment that involved student (inexperienced) bidders with a construction project management background. The results show that the variations in bids over time for full information feedback condition are statistically significant, but not for bids from bidders with partial bidding feedback information. Bidders with full bidding feedback information are more competitive than those with partial bidding feedback information. The findings add to both our theoretical and empirical understanding of construction bidding: an understanding of the process of changes in the price of building work, and how the process can be manipulated through the release of bidding feedback information

Promotion of breastfeeding by dental teams: A survey of early career dentists

Breastfeeding provides a range of positive health benefits for both mother and baby. Due to maternal exemption of dental charges, dentists have the access and opportunity to provide information to expectant and nursing mothers, and are in an optimal position to positively influence breastfeeding behaviour. A cross-sectional survey of early career dentists in the East Midlands was conducted. The survey questionnaire assessed levels of confidence, knowledge and practice regarding breastfeeding. Barriers identified in supporting and encouraging breastfeeding were lack of knowledge (81%; n=57), lack of confidence (63%; n=44) and lack of time (52%; n=36). Approximately two thirds reported they had never received training and a majority felt they would benefit from this (86%; n=60). Early career dentists in the East Midlands reported limited knowledge and a lack of confidence in the delivery of breastfeeding advice. Wider incorporation of training into undergraduate and postgraduate programmes could be considered, which may improve breastfeeding rates

Social Communication Across Reproductive Boundaries: Hormones And The Auditory Periphery Of Songbirds And Frogs

Most animals experience reproductive transitions in their lives; for instance, reaching reproductive maturity or cycling in and out of breeding condition. Some reproductive transitions are abrupt, while others are more gradual. In most cases, changes in communication between the sexes follow the time course of these reproductive transitions and are typically thought to be coordinated by steroid hormones. We know a great deal about hormonal control of communication behaviors in birds and frogs, as well as the central neural control of these behaviors. There has also been significant interest in the effects of steroid hormones on central nervous system structures that control both the production and reception of communication signals associated with reproductive behaviors. However, peripheral sensory structures have typically received less attention, although there has been growing interest in recent years. It is becoming clear that peripheral sensory systems play an important role in reproductive communication, are plastic across reproductive conditions, and, in some cases, this plasticity may be mediated by steroid hormones. In this paper, we discuss recent evidence for the role of peripheral auditory structures in reproductive communication in birds and frogs, the plasticity of the peripheral auditory system, and the role of steroid hormones in mediating the effects of the peripheral auditory system on reproductive communication. We focus on both seasonal and acute reproductive transitions, introduce new data on the role of hormones in modulating seasonal patterns, and make recommendations for future work

Progesterone And Prostaglandin F2α Induce Species-Typical Female Preferences For Male Sexual Displays In Cope\u27s Gray Treefrog (Hyla Chrysoscelis)

Endocrine systems play critical roles in facilitating sexual behavior in seasonally breeding vertebrates. Much of the research exploring this topic has focused on the endocrine correlates of signaling behavior in males and sexual proceptivity in females. What is less understood is how hormones promote the expression of the often complex and highly selective set of stimulus–response behaviors that are observed in naturally breeding animals. In female frogs, phonotaxis is a robust and sensitive bioassay of mate choice and is exhibited by gravid females during the breeding season. In stark contrast, females exhibit low phonotactic responsiveness outside the breeding season, but the administration of hormones can induce sexual proceptivity. Here we test the hypothesis that manipulation of a minimal set of reproductive hormones—progesterone and prostaglandin F2α—are capable of evoking not only proceptive behavior in non-breeding females, but also the patterns of intraspecific selectivity for male sexual displays observed in gravid females tested during the breeding season. Specifically, we investigated whether preferences for faster call rates, longer call durations, and higher call efforts were similar between breeding and hormone-treated females of Cope\u27s gray treefrog (Hyla chrysoscelis). Hormone injections induced patterns of selective phonotaxis in non-breeding females that were remarkably similar to those observed in breeding females. These results suggest that there may be an important contribution of hormonal pleiotropy in regulating this complex, acoustically-guided sexual behavior. Our findings also support the idea that hormonal induction could be used to evaluate hypotheses about selective mate choice, and its underlying mechanisms, using non-breeding females

Transmission of SARS-CoV-2 in educational settings in 2020: a review

Objectives: School closures have been used as a core non pharmaceutical intervention (NPI) during the COVID-19 pandemic. This review aims at identifying SARS-CoV-2 transmission in educational settings during the first waves of the pandemic.Methods: This literature review assessed studies published between December 2019 and April 1, 2021 in Medline and Embase, which included studies that assessed educational settings from approximately January 2020 to January 2021. The inclusion criteria were based on the PCC framework (P-Population, C-Concept, C-Context). The study Population was restricted to people 1-17 years old (excluding neonatal transmission), the Concept was to assess child-to-child and child-to-adult transmission, while the Context was to assess specifically educational setting transmission.Results: Fifteen studies met inclusion criteria, ranging from daycare centers to high schools and summer camps, while eight studies assessed the re-opening of schools in the 2020-2021 school year. In principle although there is sufficient evidence that children can both be infected by and transmit SARS-CoV-2 in school settings, the SAR remain relatively low -when NPI measures are implemented in parallel. Moreover, although the evidence was limited there was an indication that younger children may have a lower SAR than adolescents. Conclusions: Transmission in educational settings in 2020 was minimal -when NPI measures were implemented in parallel. However, with an upsurge of cases related to variants of concern, continuous surveillance and assessment of the evidence is warranted to ensure the maximum protection of the health of students and the educational workforce, while also minimising the numerous negative impacts that school closures may have on children

All's well that begins Wells: Celebrating 60 years of Animal Behaviour and 36 years of research on anuran social behaviour

The scientific study of frogs and toads as important systems in behavioural ecology traces its roots to an influential review published in this journal 36 years ago (Wells 1977a, ‘The social behaviour of anuran amphibians’, Animal Behaviour, 25, 666–693). In just 28 pages, Wells summarized the state of knowledge on important behaviours associated with anuran breeding and introduced an evolutionary framework ‘for understanding the relationship between social behaviour and ecology’ (page 666) that was largely lacking in earlier treatments of this group. Not only is Wells's review one of the most cited papers ever published in Animal Behaviour, it is also responsible for setting broad research agendas and shaping much of our current thinking on social behaviour in an entire order of vertebrates. As such, it is entirely appropriate that we honour Wells's review and its contributions to the study of animal behaviour in this inaugural essay celebrating 12 papers selected by the community as the most influential papers published in the 60-year history of Animal Behaviour. In our essay, we place Wells's review in historical context at the dawn of behavioural ecology, highlight the field's progress in answering some major research questions outlined in the review, and provide our own prospectus for future research on the social behaviour of anuran amphibians. Highlights ► This essay celebrates Kent Wells's (1977, Animal Behaviour, 25, 666–693) paper, ‘The social behaviour of anuran amphibians’. ► We place the article in historical context and outline its major contributions. ► We discuss progress on anuran social behaviour since its publication in 1977. ► We provide our own prospectus on the future of anuran behavioural ecology

A reliability study of radiographic measures of total ankle replacement position: an analysis from the OARS cohort

Objective: There is no validated radiographic measurement to diagnose prosthetic complication(s) following total ankle replacements (TARs) although a number of angular and linear measurements, used to define the TAR position on postoperative radiographs, have been recommended to detect prosthetic loosening. The aim of this study was to test the intra- and interobserver reliability of these measurements.  Materials and methods: This is a prospective study embedded within a multicentre cohort study. Following sample size calculation, 62 patients were analysed. Six measurements were performed on the first postoperative anteroposterior and lateral ankle radiographs: angles α and β, and length “a” defined the craniocaudal position of the tibial component, while angle γ, and lengths “b” and “c” defined the angular position of the talar component. Measurements were recorded by three independent observers. Inter- and intraobserver reliability was assessed with intraclass correlation coefficient (ICC), Bland-Altman plots, and within-subject coefficients of variation (CV).  Results: The intrarater ICC was “almost perfect” (ICC 0.83–0.97) for all six measurements. The interrater ICC was “substantial” to “almost perfect” (ICC 0.69–0.93). The mean difference in intrarater angular measurements was ≤ 0.6° and ≤ 0.8 mm for linear measurements, and ≤ 2.2° and ≤ 2.1 mm for interrater measurements. Maximum CV for the interrater linear measurements (≤ 17.7%) more than doubled that of the angular measurements (≤ 8.0%). The maximum width of the 95% limits of agreement was 6.5° and 8.4 mm for intrarater measures, and 8.9° and 10.6 mm for interrater measurements.  Conclusion: Angular measures are more reliable than linear measures and have potential in routine clinical practice for TAR position assessment

μ -Opioid receptor activation and noradrenaline transport inhibition by tapentadol in rat single locus coeruleus neurons.

BACKGROUND AND PURPOSE: Tapentadol is a novel analgesic that combines moderate μ-opioid receptor agonism and noradrenaline reuptake inhibition in a single molecule. Both mechanisms of action are involved in producing analgesia; however, the potency and efficacy of tapentadol in individual neurons has not been characterized. EXPERIMENTAL APPROACH: Whole-cell patch-clamp recordings of G-protein-coupled inwardly rectifying K(+) (KIR 3.x) currents were made from rat locus coeruleus neurons in brain slices to investigate the potency and relative efficacy of tapentadol and compare its intrinsic activity with other clinically used opioids. KEY RESULTS: Tapentadol showed agonist activity at μ receptors and was approximately six times less potent than morphine with respect to KIR 3.x current modulation. The intrinsic activity of tapentadol was lower than [Met]enkephalin, morphine and oxycodone, but higher than buprenorphine and pentazocine. Tapentadol inhibited the noradrenaline transporter (NAT) with potency similar to that at μ receptors. The interaction between these two mechanisms of action was additive in individual LC neurons. CONCLUSIONS AND IMPLICATIONS: Tapentadol displays similar potency for both µ receptor activation and NAT inhibition in functioning neurons. The intrinsic activity of tapentadol at the μ receptor lies between that of buprenorphine and oxycodone, potentially explaining the favourable profile of side effects, related to μ receptors. LINKED ARTICLES: This article is part of a themed section on Opioids: New Pathways to Functional Selectivity. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-2.NHMRC Grant Numbers: 1011979 & 104596