Interdisciplinary approaches to zoonotic disease

Zoonotic infections are on the increase worldwide, but most research into the biological, environmental and life science aspects of these infections has been conducted in separation. In this review we bring together contemporary research in these areas to suggest a new, symbiotic framework which recognises the interaction of biological, economic, psychological, and natural and built environmental drivers in zoonotic infection and transmission. In doing so, we propose that some contemporary debates in zoonotic research could be resolved using an expanded framework which explicitly takes into account the combination of motivated and habitual human behaviour, environmental and biological constraints, and their interactions

Improved maximum likelihood estimators in a heteroskedastic errors-in-variables model

This paper develops a bias correction scheme for a multivariate heteroskedastic errors-in-variables model. The applicability of this model is justified in areas such as astrophysics, epidemiology and analytical chemistry, where the variables are subject to measurement errors and the variances vary with the observations. We conduct Monte Carlo simulations to investigate the performance of the corrected estimators. The numerical results show that the bias correction scheme yields nearly unbiased estimates. We also give an application to a real data set.Comment: 12 pages. Statistical Paper

Interference of breast implants with echocardiographic image acquisition and interpretation

Echocardiography is one of the most important diagnostic testing in cardiology. The presence of a breast implant overlying heart can cause significant impairment of the echocardiographic acoustic window. Breast implants are increasing in popularity in the USA and the Federal Drug and Food Administration (FDA) just approved silicone implants again. In this review, the impact of silicone breast implant on the echocardiographic image acquisition and interpretation is discussed

Sport psychology in an Olympic swimming team: Perceptions of the management and coaches

It has been over 20 years since research has been published on perceptions of sport psychology services in Olympic sport, and this work spanned multiple sports, had a North American focus, and did not report management’s views. In this study, we resurrect this line of inquiry through the investigation of management and coaches’ perceptions of sport psychology in a European Olympic swimming team. Following semistructured interviews with 12 members of the management and coaching staff, we identified themes relating to retrospective reflections of past psychology-related services (i.e., negative previous experiences, lack of understanding, unease with service, threat to coach-swimmer relationship) and prospective projections of future psychology-related services (i.e., recognition of importance, scope of target client groups, roles with the coaches, confidentiality issues, practitioner characteristics). Within this team, sport psychology was perceived largely negatively, but despite this, the coaches and management recognized the importance and potential of the service. This apparent disparity can be explained by a range of factors, but the team culture, delivery method, and individual personalities appear to be particularly influential in this regard. To enhance the quality and receptivity of service provision, researchers and practitioners should effectively communicate with recipients of the service and consider not just what is delivered but by whom and how it is delivered

Olympic coaching excellence: A quantitative study of Olympic swimmers' perceptions of their coaches.

Although coaching is a co-created process, researchers investigating the psychological aspects of Olympic coaching have tended to overlook the perceptions of athletes and whether these distinguish between performance-related outcomes. The objective of this research was to examine whether athletes' perceptions of their coaches discriminate between world-leading (i.e., Olympic gold medal winning) and world-class (i.e., Olympic non-gold medal winning) coaches. Observer-reported psychometric questionnaires were completed by 38 Olympic swimmers who had collectively won 59 Olympic medals, of which 31 were gold. The questionnaires assessed perceptions of 12 variables within the Big Five personality traits, the dark triad, and emotional intelligence, and the data was analyzed using three one-way multivariate analysis of variance and follow-up univariate F-tests. The results showed that world-leading coaches were perceived to be significantly higher on conscientiousness, openness to experience, perception of emotion, and management of others emotion, and lower on narcissism, than world-class coaches. This suggests that athletes' perceptions of their coaches may discriminate between world-leading and world-class coaches. The implications for coaches' psychological development are discussed and compared with previously reported Olympic coaches' perceptions of themselves

The challenges faced in the design, conduct and analysis of surgical randomised controlled trials

Randomised evaluations of surgical interventions are rare; some interventions have been widely adopted without rigorous evaluation. Unlike other medical areas, the randomised controlled trial (RCT) design has not become the default study design for the evaluation of surgical interventions. Surgical trials are difficult to successfully undertake and pose particular practical and methodological challenges. However, RCTs have played a role in the assessment of surgical innovations and there is scope and need for greater use. This article will consider the design, conduct and analysis of an RCT of a surgical intervention. The issues will be reviewed under three headings: the timing of the evaluation, defining the research question and trial design issues. Recommendations on the conduct of future surgical RCTs are made. Collaboration between research and surgical communities is needed to address the distinct issues raised by the assessmentof surgical interventions and enable the conduct of appropriate and well-designed trials.The Health Services Research Unit is funded by the Scottish Government Health DirectoratesPeer reviewedPublisher PD

The Compelling Case for Indentation as a Functional Exploratory and Characterization Tool

The utility of indentation testing for characterizing a wide range of mechanical properties of brittle materials is highlighted in light of recent articles questioning its validity, specifically in relation to the measurement of toughness. Contrary to assertion by some critics, indentation fracture theory is fundamentally founded in Griffith–Irwin fracture mechanics, based on model crack systems evolving within inhomogeneous but well-documented elastic and elastic–plastic contact stress fields. Notwithstanding some numerical uncertainty in associated stress intensity factor relations, the technique remains an unrivalled quick, convenient and economical means for comparative, site-specific toughness evaluation. Most importantly, indentation patterns are unique fingerprints of mechanical behavior and thereby afford a powerful functional tool for exploring the richness of material diversity. At the same time, it is cautioned that unconditional usage without due attention to the conformation of the indentation patterns can lead to overstated toughness values. Limitations of an alternative, more engineering approach to fracture evaluation, that of propagating a pre-crack through a 'standard' machined specimen, are also outlined. Misconceptions in the critical literature concerning the fundamental nature of crack equilibrium and stability within contact and other inhomogeneous stress fields are discussed.This is the author accepted manuscript. The final version is available from Wiley via http://dx.doi.org/10.1111/jace.1372

Programmability of Chemical Reaction Networks

Motivated by the intriguing complexity of biochemical circuitry within individual cells we study Stochastic Chemical Reaction Networks (SCRNs), a formal model that considers a set of chemical reactions acting on a finite number of molecules in a well-stirred solution according to standard chemical kinetics equations. SCRNs have been widely used for describing naturally occurring (bio)chemical systems, and with the advent of synthetic biology they become a promising language for the design of artificial biochemical circuits. Our interest here is the computational power of SCRNs and how they relate to more conventional models of computation. We survey known connections and give new connections between SCRNs and Boolean Logic Circuits, Vector Addition Systems, Petri Nets, Gate Implementability, Primitive Recursive Functions, Register Machines, Fractran, and Turing Machines. A theme to these investigations is the thin line between decidable and undecidable questions about SCRN behavior

Long COVID-19 and Peripheral Serotonin: A Commentary and Reconsideration

George M Anderson,1,2 Edwin H Cook,3 Randy D Blakely,4 James S Sutcliffe,5,6 Jeremy Veenstra-VanderWeele7,8 1Yale Child Study Center, Yale University School of Medicine, New Haven, CT, USA; 2Department of Laboratory Medicine, Yale University School of Medicine, New Haven, CT, USA; 3Department of Psychiatry, College of Medicine, University of Illinois at Chicago, Chicago, IL, USA; 4FAU Stiles-Nicholson Brain Institute, Department of Biomedical Science, Florida Atlantic University, Jupiter, FL, USA; 5Department of Molecular Physiology & Biophysics, Vanderbilt University, Nashville, TN, USA; 6Department of Psychiatry & Behavioral Sciences, Vanderbilt University, Nashville, TN, USA; 7Department of Psychiatry, College of Medicine, Columbia University, New York, NY, USA; 8New York State Psychiatric Institute, Columbia University, New York, NY, USACorrespondence: George M Anderson, Yale Child Study Center, 230 S. Frontage Road, New Haven, CT, USA, Email [email protected]: We believe there are serious problems with a recently published and highly publicized paper entitled “Serotonin reduction in post-acute sequelae of viral infection.” The blood centrifugation procedure reportedly used by Wong et al would produce plasma that is substantially (over 95%) depleted of platelets. Given this, their published mean plasma serotonin values of 1.2 uM and 2.4 uM for the control/contrast groups appear to be at least 30 to 60 times too high and should be disregarded. The plasma serotonin values reported for the long COVID and viremia patients also should be disregarded, as should any comparisons to the control/contrast groups. We also note that the plasma serotonin means for the two control/contrast groups are not in good agreement. In the “Discussion” section, Wong et al state that their results tend to support the use of selective serotonin reuptake inhibitors (SSRIs) for the treatment of COVID-19, and they encourage further clinical trials of SSRIs. While they state that, “Our animal models demonstrate that serotonin levels can be restored and memory impairment reversed by precursor supplementation or SSRI treatment”, it should be noted that no data are presented showing an increase or restoration in circulating serotonin with SSRI administration. In fact, one would expect a marked decline in platelet serotonin due to SSRIs’ effective inhibition of the platelet serotonin transporter. Wong et al hypothesize that problems of long COVID arise from too little peripheral serotonin. However, given the frequent presence of a hyperaggregation state in long COVID, and the known augmenting effects of platelet serotonin on platelet aggregation, it is plausible to suggest that reductions in platelet serotonin might be associated with a lessening of the cardiovascular sequelae of COVID-19.Keywords: serotonin, COVID-19, plasma, platelets, long COVID, viral infectio

Unprecedented mode of action of phenothiazines as ionophores unravelled by an NDH-2 bioelectrochemical assay platform

Type II NADH:quinone oxidoreductase (NDH-2) plays a crucial role in the respiratory chains of many organisms. Its absence in mammalian cells makes NDH-2 an attractive new target for developing antimicrobials and anti-protozoal agents. We established a novel bioelectrochemical platform to characterize the catalytic behavior of NDH-2 from Caldalkalibacillus thermarum and Listeria monocytogenes strain EGD-e while bound to native-like lipid membranes. Catalysis of both NADH oxidation and lipophilic quinone reduction by membrane-bound NDH-2 followed the Michaelis–Menten model; however, the maximum turnover was only achieved when a high concentration of quinone (>3 mM) was present in the membrane, suggesting that quinone availability regulates NADH-coupled respiration activity. The quinone analogue 2-heptyl-4-hydroxyquinoline-N-oxide inhibited C. thermarum NDH-2 activity and its potency is higher in a membrane environment compared to assays performed with water-soluble quinone analogues, demonstrating the importance of testing compounds under physiologically relevant conditions. Furthermore, when phenothiazines, one of the most commonly identified NDH-2 inhibitors, were tested, they did not inhibit membrane-bound NDH-2. Instead, our assay platform unexpectedly suggests a novel mode of phenothiazine action where chlorpromazine, a promising anti-tubercular agent and key medicine used to treat psychotic disorders, is able to disrupt pH gradients across bacterial membranes