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The use of molecular diagnostic techniques in the study of ticks and tick-borne agents has increased dramatically in the last few decades, and while conferring the advantages of rapidity, sensitivity and accuracy, they can also be misused by the research community, who have shown an increasing overreliance on the data they produce, often completely abandoning more traditional approaches such as microscopy and serology. In this short review examples are provided of ‘findings’ that are apparently at odds with well-established eco-epidemiological knowledge, ranging from descriptions of new species of pathogens to their detection in new hosts and ticks, often immediately incriminated as new reservoir hosts and vector ticks, respectively. Most examples have been taken from the Piroplasmorida or “piroplasm” species as they are often called. Researchers are urged to utilize molecular methods with as much awareness as possible of the system or systems they are investigating, and journal editors and their teams of reviewers should be encouraged to adopt a more critical approach to papers that contain data based solely on molecular methods without due regard to the underlying biology. Explanations for such findings should be offered and discussed. [ABSTRACT FROM AUTHOR]

Prior to its identification as the vector of Lyme borreliosis spirochaetes in Europe in 1983, interest in Ixodes ricinus (L.) was moderate and mainly concerned the transmission of pathogens to farm animals and of tick-borne encephalitis virus to humans. The situation now is very different, and more papers have been published on I. ricinus than on any other ixodid tick species. However, this large literature is scattered and in recent years has become dominated by the molecular detection and characterization of the many pathogens that I. ricinus transmits. Several decades have now elapsed since a review addressing its basic biology and ecology appeared, and the present publication seeks to present basic aspects of its biology and ecology that are related to its role as a vector of disease agents, including its life cycle, feeding behaviour, host relations, survival off the host, and the impact of weather and climate. [ABSTRACT FROM AUTHOR]

Four members of the Ixodes ricinus species complex, Ixodes pacificus, Ixodes persulcatus , Ixodes ricinus and Ixodes scapularis , have, between them, a worldwide distribution within the northern hemisphere. They are responsible for the transmission of several animal and human pathogens, including the causal agents of Lyme borreliosis, tick-borne encephalitis, human granulocytic anaplasmosis and human babesiosis. Despite the importance of these ticks as vectors, the knowledge and understanding of the role that diapause plays in their complex life cycles are confused and incomplete. In view of the continuing geographic spread of these tick species, as well as the effects of climate change on vector-borne diseases, it is timely to encourage research on diapause phenomena to improve understanding of their biology and of pathogen transmission dynamics. In our review we seek to clarify thinking on the topic and to address gaps in our knowledge that require the attention of researchers. [ABSTRACT FROM AUTHOR]

There is a need to radically increase mobility of terrain vehicles through new modalities of vehicle locomotion, i.e., by establishing a new technological paradigm in vehicle dynamics and mobility. The new paradigm greatly applies to military vehicles for the radical improvement of tactical and operational mobility. This article presents a new technological paradigm of agile tire slippage dynamics that is studied as an extremely fast and exact response of the tire–soil couple to (i) the tire dynamic loading, (ii) transient changes of gripping and rolling resistance conditions on uniform stochastic terrains and (iii) rapid transient changes from one uniform terrain to a different uniform terrain. Tire longitudinal relaxation lengths are analyzed to characterize the longitudinal relaxation time constants. A set of agile characteristics is also considered to analyze agile tire slippage dynamics within a time interval that is close to the tire longitudinal relaxation time constants. The presented paradigm of agile tire slippage dynamics lays out a foundation to radically enhance vehicle terrain mobility by controlling the tire slippage in its transient phases to prevent the immobilization of a vehicle. Control development basis and requirements for implementing an agile tire slippage control are also analyzed and considered. [ABSTRACT FROM AUTHOR]

Military vehicle convoys are logistical supply chains that are heavily relied upon and are very often operated in severe terrain conditions. As it is shown in this article, the convoy mobility analytical estimation becomes a rather difficult task since the track, and thus tire–terrain interaction, is formed by multiple vehicles of a convoy driving over the same track. Furthermore, the distribution of power between the drive wheels of each convoy vehicle is a key factor in convoy mobility enhancement. A vehicle can be immobilized due to inappropriate combination of a power supply to a wheel and its poor tire–terrain properties. This leads to mobility loss of several or all the vehicles of the convoy. To the contrary, power wheel distributions concerted with wheel–terrain conditions improve mobility of a wheel, vehicle and the entire convoy. This article crystallizes the main factors that impact convoy mobility, discusses the factors at a descriptive level of vehicle dynamics control and then results in a convoy on-line mobility estimation and control strategy. [ABSTRACT FROM AUTHOR]

This is the first study to determine the density of questing Ixodes ricinus in northern Norway. It was performed at two sites in Brønnøy, which has been known for its tick permissive habitats for decades and is one of the northernmost habitats with an abundant I. ricinus population in the world. From April to November 2011, all stages of host-seeking I. ricinus were collected from the two sites. The overall prevalence of nymphs infected with Borrelia burgdorferi sensu lato was 21% and that of adult ticks 46%. The rates of the genospecies Borrelia afzelii , Borrelia garinii , and Borrelia valaisiana were similar to findings in most other studies in Scandinavia, with B. afzelii by far the most prevalent at 76%. The high Borrelia -infection prevalence in ticks from Brønnøy may explain the high incidence rate of reported Lyme borreliosis in the municipality. [ABSTRACT FROM AUTHOR]

Henri Poincaré acquired a reputation in his lifetime for being difficult to read. It was said that he missed out important steps in his arguments, assumed the truth of claims that would be difficult if not impossible to prove, and in short that he lacked rigour. In the years after his death this view coalesced into an exaggerated claim that his work was simply too vague, and has become a cliché. This paper argues that Poincaré was far from indifferent to rigour, and that what characterises his work is an attempt to convey a particular sense of what it is to understand a topic. Throughout his working life Poincaré was concerned to promote the understanding of many domains of mathematics and physics. This is as apparent in his views about geometry, his conventionalism, and his theory of knowledge, as it is in his work on electricity and optics, on number theory, and function theory. It is one of the ways Poincaré discharged his responsibilities as a scientist, and that it accounts not only for a surprising degree of unity in his work but also gives it its distinctive character--at once profound and elusive. [ABSTRACT FROM AUTHOR]

We describe a 79-year-old Irish man who, because he had hyposplenism and splenic atrophy due to adult celiac disease, became critically ill from a severe Babesia divergens infection. Greater awareness of the possible consequences of splenic dysfunction from adult celiac disease, such as serious pneumococcal infections and babesiosis, is warranted. [ABSTRACT FROM AUTHOR]

Abstract: A recent history of failed clinical trials suggests that waiting until even the early stages of onset of Alzheimer's disease may be too late for effective treatment, pointing to the importance of early intervention in young people. Early intervention will require markers of Alzheimer's risk that track with genotype but are capable of responding to treatment. Here, we sought to identify a functional MRI signature of combined Alzheimer's risk imparted by two genetic risk factors. We used a task of executive attention during fMRI in participants genotyped for two Alzheimer's risk alleles: APOE-ε4 and CLU-C. Executive attention is a sensitive indicator of the progression of Alzheimer's even in the early stages of mild cognitive impairment, but has not yet been investigated as a marker of Alzheimer's risk in young adults. Functional MRI revealed that APOE-ε4 and CLU-C had an additive effect on brain activity such that increased combined genetic risk was associated with decreased brain activity during executive attention, including in the medial temporal lobe, a brain area affected early in Alzheimer's pathogenesis. [Copyright &y& Elsevier]

Abstract: Brake-based traction control systems (TCs), which utilize the brake of a spinning wheel, are widely used in various vehicles. Recently, TCs were applied to all-wheel drive construction equipment. Such machines employ various types of driveline systems to control torque split between the drive wheels and thus improve vehicle traction performance. As experimental research showed, the interaction between the TC system and the axle drive can lead to unpredictable changes in vehicle traction. Lack of analytical work motivated a study of the interaction/impact of the two systems on each other and then traction a 4×4 single bucket loader. This paper presents an analytical and computer model of the loader’s driveline system. Mechanical power distributions between the driving wheels are analyzed when a brake mechanism of a spinning wheel is on/off. Computer simulations were conducted on surfaces with different grip conditions of the four wheels, with longitudinal and lateral inclination of the loader when scooping the material. The paper discusses simulation results and presents fundamentals for the fusion of the driveline and TC systems to improve the loader’s traction. [Copyright &y& Elsevier]

Abstract: Rhipicephalus sanguineus, the brown dog tick, kennel tick, or pan-tropical dog tick, is probably the most widespread ixodid tick, colonising both human and canine dwellings. It is of great significance in both human and veterinary medicine as a vector of several important pathogens and can also cause clinical illness in heavy infestations of dogs. However, there are still significant taxonomic uncertainties, and it is probable that some records of this tick refer to other species. Most past reviews have been broad-ranging or have focused on the pathogens that R. sanguineus transmits, and relatively few have considered its biology in detail or the issues around its true identity. The present review has paid most attention to the taxonomy of R. sanguineus and to the ecological factors that influence tick survival and distribution, particularly in a climate change context. It is evident that more research is required on the systematics of the R. sanguineus species complex, in order to elucidate the epidemiology and prevention of the diseases that it transmits, and to provide the relevant biological data required for development of predictive models of future tick distribution in a climate change scenario. [Copyright &y& Elsevier]

Abstract: Babesiosis is a zoonosis caused by tick-transmitted intraerythrocytic protozoa of the Phylum Apicomplexa. The disease mostly occurs in the USA, but cases have also been reported in several European countries, in Egypt, India, Japan, Korea, Taiwan, and South Africa. The main pathological event is lysis of erythrocytes resulting in haemolytic anaemia, which in severe cases may lead to organ failure and death, particularly in immunocompromised patients. The 2 groups of parasites involved, Babesia microti-like and Babesia sensu stricto (s.s.) species, differ in their life cycle characteristics and susceptibility to antibabesial drugs. Molecular taxonomy is now making a major contribution to the identification of novel pathogens within both groups. Effective treatment of severe cases was initially hampered by the lack of specific antibabesial drugs for human use, but increased use of supportive measures and of the recently developed antimalarial, atovaquone, particularly in combination with azithromycin, has improved the prospects for management of acute disease especially when caused by Babesia s.s. species. Prevention should be based primarily on increasing the awareness of physicians and the public to the risks, but infection from blood transfusions is particularly difficult to prevent. Expanding deer populations, resulting in wider distribution and greater abundance of ticks, heightened medical awareness, and growing numbers of immunocompromised patients are likely to result in a continuing rise of reported cases. [Copyright &y& Elsevier]

Abstract: A recent climate experiment predicted that average maximum summer temperatures in southern regions of the British Isles may approach 30°C by the year 2020. An opportunity for retrospective analysis of the implications of such a change for tick phenology and disease transmission was presented by the coincidence of unusually high early summer temperatures in 1976 with the collection of tick data from sites in Ireland where host availability was controlled. Subsequent identification of diapause threshold periods and simulation of temperature-dependent tick development showed that high summer temperatures can cause mass transfer of ticks between development cohorts, resulting in increased activity and therefore increased disease transmission in late autumn and early spring. This suggests that in northern temperate regions of Europe global warming is likely to cause changes in the seasonal patterns of tick-borne diseases. [Copyright &y& Elsevier]

Abstract: Delay discounting (DD), the tendency to prefer smaller, sooner rewards to larger, later ones, is an important indicator of self-control. Assessments of DD superficially require individuals to make choices based on motivational processes. However, several lines of evidence suggest that DD may be systematically related to cognitive ability. We sought to provide a definitive assessment of the relation between DD and intelligence via quantitative research synthesis. A comprehensive literature search in two electronic databases yielded 24 eligible studies with 26 effect sizes in total. Meta-analysis revealed that, across studies, higher intelligence was associated with lower DD (random effects model weighted mean r =−0.23). Studies using reward schemes in which payoffs were subject to chance (i.e., involving either a chance of receiving one choice or random selection of one choice) showed weaker associations between DD and intelligence than did studies in which payoffs were all hypothetical or all real. Other moderator analyses revealed no influence of DD measure, DD choice paradigm, or intelligence type. There was no evidence of publication bias. Given clear evidence for a negative relation between DD and intelligence, investigating the processes that support or moderate this relation would be worthwhile. [Copyright &y& Elsevier]

Abstract: Three possible functions of Ti-peroxy gel are: reduction of the inflammatory response through the reduction of hydrogen peroxide and other reactive oxygen species; creation of a favorable surface for calcium phosphate nucleation; and as a transitional layer between the compliant surrounding tissue and the stiff titanium. Traditional surface characterization techniques operate in high vacuum environments that alter the actual sample–solution interface. Our studies used techniques that allowed samples to remain in solution and be observed over time. Atomic force microscopy (AFM) force–distance curves, electrochemical impedance spectroscopy (EIS), and Raman spectroscopy were each used in situ to define kinetic and mechanical properties of Ti-peroxy gel as it formed over time on titanium during exposure to hydrogen peroxide. Our studies enabled us to monitor real-time changes in the native oxide layer on titanium in hydrogen peroxide containing solution, including the formation of a Ti-peroxy gel layer above the native oxide. Peaks attributed to Ti-peroxy gel were seen to emerge over the course of several hours using in situ Raman spectroscopy. Force–distance curves suggest a layer that thickens with time on the titanium sample surface. EIS data showed that changes in the surface layers could be monitored in solution over time. [Copyright &y& Elsevier]

Abstract: Most cases of human babesiosis are caused either by Babesia divergens in Europe or Babesia microti in America. B. microti, once regarded as a single species, occurs as a world-wide species complex and although both phenotypic and genotypic features lend support to suggestions that zoonotic B. microti may occur in Europe, convincing medical evidence is lacking. Several B. divergens-like parasites have emerged in the last few years, but 18S rRNA gene analysis suggests that B. divergens ‘sensu stricto’ is restricted to European (and North African) cattle. Some of the B. divergens-like parasites only differ from the bovine type by a few bases, and it remains to be determined whether this is sufficient to accord them separate species status. Comparative biology should support genetic data in taxonomic studies of both B. divergens and B. microti. [Copyright &y& Elsevier]

Abstract: Knowledge of the duration of tick feeding can contribute to assessment of disease transmission risk, and may be estimated from changes in body dimensions during engorgement. Application of this approach to the European tick, Ixodes ricinus, is described here. Nymphal and adult female I. ricinus ticks were detached at predetermined intervals from laboratory rabbits and their state of engorgement estimated by calculating either the scutal index (the ratio of the width of the scutum to the length of the idiosoma) or the coxal index (the ratio of the width of the scutum to the distance between the basal coxae of the fourth pair of legs – the coxal gap). The coxal index proved to be more accurate in estimating duration of feeding over the first 24h, but the scutal index was more accurate later in feeding. The coxal index may be used in combination with the scutal index to estimate the period of time that ticks removed from patients have been feeding, thus assisting with the assessment of pathogen transmission risk. [Copyright &y& Elsevier]

Abstract: Decision making has both cognitive and affective components, but previous neuroimaging studies in this domain predominantly have focused on affect and reward. The current study examined a decision-making paradigm that placed strong demands on cognitive control processes by making reward payoffs contingent upon decision-making history. Payoffs were maximized by choosing the option that, paradoxically, was associated with a lower payoff on the immediate trial. Temporal integration requirements were manipulated by varying, across conditions, the window of previous trials over which the reward function was calculated. The cognitive demands of the task were hypothesized to engage neural systems responsible for integrating and actively maintaining actions and outcomes over time and the top-down biasing of response selection. Brain activation was monitored with functional magnetic resonance imaging (fMRI) using a mixed-blocked and event-related design to extract both transient and sustained neural responses. A network of brain regions commonly associated with cognitive control functions, including bilateral prefrontal cortex (PFC), bilateral parietal cortex, and medial frontal cortex, showed selectively sustained activation during the task. Increasing temporal integration demands led to a shift from transient to sustained activity in additional regions, including right hemisphere dorsolateral and frontopolar PFC. These results demonstrate the contribution of cognitive control mechanisms to temporally extended decision-making paradigms and highlight the benefits of decomposing activation responses into sustained and transient components. [Copyright &y& Elsevier]

Abstract: Zoonotic babesiosis has received increased attention recently, due mainly to the interest in tickborne zoonotic diseases generated by the emergence of Lyme borreliosis and to increased awareness of diagnostic and treatment difficulties associated with co-infection cases. The vast majority of European cases have been caused by Babesia divergeas in splenectomised patients, and although rare, this disease is very dangerous, requiring aggressive treatment. The use of atovaquone, a recently developed anti-protozoan agent for human treatment, may be considered in future cases. Most human babesiosis caused by B. microti have occurred in the north-eastern states of the USA and can affect spleen-intact as well as asplenic patients. The majority of infections are subclinical or follow a mild chronic course, but dangerous acute infections can occur in immunocompromised patients. The role of B. microti in apparently unresponsive cases of Lyme borreliosis and treatment of co-infections require further investigation. The zoonotic potential of B. microti in Europe is still unresolved, but the vector competence of Ixodes ricinus for at least some European (and American) strains has been demonstrated. [Copyright &y& Elsevier]

• Ixodes ricinus : state of the science. • Ixodes ricinus : unresolved questions. • Ixodes ricinus : future research. In spite of many decades of intensive research on Ixodes ricinus , the castor bean tick of Europe, several important aspects of its basic biology remain elusive, such as the factors determining seasonal development, tick abundance and host specificity, and the importance of water management. Additionally, there are more recent questions about the geographical diversity of tick genotypes and phenotypes, the role of migratory birds in the ecoepidemiology of I. ricinus , the importance of protective immune responses against I. ricinus , particularly in the context of vaccination, and the role of the microbiome in pathogen transmission. Without more detailed knowledge of these issues, it is difficult to assess the likely effects of changes in climate and biodiversity on tick distribution and activity, to predict potential risks arising from new and established tick populations and I. ricinus -borne pathogens, and to improve prevention and control measures. This review aims to discuss the most important outstanding questions against the backdrop of the current state of knowledge of this important tick species. [ABSTRACT FROM AUTHOR]

• The distribution of ticks in Ireland chiefly coincides with historical high incidence areas of bovine babesiosis. • The infection rate of questing nymphs with B. burgdorferi s.l. has remained stable over the last 3 decades. • The prevalence of the various genospecies has remained essentially unchanged since the 1990′s. • The risk of contracting LB from a tick bite remains low even in woodlands where tick abundance is comparatively high. It is often suggested that due to climate and environmental policy changes, the risk from tick-borne disease is increasing, particularly at the geographical limits of the vector distribution. Our project aimed to determine whether this was true for the risk of Lyme borreliosis in Ireland which is the western-most limit of Ixodes ricinus , the European vector of Borrelia burgdorferi sensu lato. The availability of a historical data set of tick infection rates compiled in the 1990s represented a unique opportunity as it provided a baseline against which current data could be compared. Following construction of a spatial predictive model for the presence and absence of I. ricinus based on data from 491 GPS locations visited between 2016 and 2019, 1404 questing nymphs from 27 sites were screened for the presence of Borrelia spp. using a TaqMan PCR aimed at the 23S rRNA gene sequence. All positive ticks were further analysed by nested PCR amplification and sequence analysis of the 5 S–23 S intergenic spacer. The model indicated that areas with the highest probability of tick presence were mostly located along the western seaboard and the Shannon and Erne river catchments, coinciding with historical high incidence areas of bovine babesiosis, while the infection rate of questing nymphs with B. burgdorferi s.l. and the prevalence of the various genospecies have remained surprisingly stable over the last 3 decades. Clear communication of the potential disease risk arising from a tick bite is essential in order to allay undue concerns over tick-borne diseases among the general public. [ABSTRACT FROM AUTHOR]

Abstract: This proof-of-concept study demonstrates that stable isotope ratios of nitrogen and carbon (expressed as δ13C and δ15N) of host blood are faithfully reproduced in unfed nymphal Ixodes ricinus that developed from larvae fed on that host. Measured isotopic discrimination (i.e. the tick–blood spacing) was between −0.1 and 0.7‰ for δ13C and 3.8 and 3.9‰ for δ15N. Both δ13C and δ15N increased significantly with tick ageing. The isotopic analysis of unfed ticks has potential for determining the physiological age of unfed ticks, for identifying the season in which the previous stage had fed and for identifying the main hosts utilized by ticks. [Copyright &y& Elsevier]

Contact probing of gaging surfaces is used throughout dimensional metrology. Probe tips such as ruby, sapphire, or diamond are commonly employed as styli for universal length measuring machines (ULMs) and coordinate measuring machines (CMMs) due to the hardness, durability, and wear resistance. Gaging surfaces of gage blocks are precision ground or lapped, with very low surface roughness to enable wringing. Damage or contamination of these surfaces can prevent wringing and lead to measurement error. Experimental investigations using a horizontal ULM and CMM have revealed that even at low force settings (≤0.16 N), probe materials such as ruby and sapphire can cause plastic deformation to hardened carbon chrome steel (such as AISI 52,100) gage block surfaces at the microscale, likely attributed to fretting-associated wear. Under some conditions, permanent transfer of material from the probe stylus to the gaging surface is possible. Results demonstrate irreversible changes and damage to gaging surfaces with repeated probe contact on a ULM and CMM. Optical microscopy, optical profilometry, and scanning electron microscopy (SEM) provide a semi-quantitative assessment of microscale plastic deformation and material transfer. X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES), and Raman techniques confirm chemical constituency of reference materials used (gage blocks and probes) and also identify makeup of deposits on gaging surfaces following probe contact. • Anomalous wear on hardened steel typically used in precision machines. • Wear and material transfer below yield limit with calculated Hertzian stress. • Ruby stylus can transfer material to steel surface. [ABSTRACT FROM AUTHOR]

Abstract: Recent evidence suggests the existence of multiple cognitive mechanisms that support the general cognitive ability factor (g). Working memory and processing speed are the two best established candidate mechanisms. Relatively little attention has been given to the possibility that associative learning is an additional mechanism contributing to g. The present study tested the hypothesis that associative learning ability, as assessed by psychometrically sound associative learning tasks, would predict variance in g above and beyond the variance predicted by working memory capacity and processing speed. This hypothesis was confirmed in a sample of 169 adolescents, using structural equation modeling. Associative learning, working memory, and processing speed all contributed significant unique variance to g, indicating not only that multiple elementary cognitive processes underlie intelligence, but also the novel finding that associative learning is one such process. [Copyright &y& Elsevier]

Abstract: Creativity is likely to be related to intelligence, though the nature of this relationship remains largely unresolved and few studies have examined creativity in the context of measures traditionally related to intelligence. Like intelligence, creativity has often been studied as a static trait or as subject to change over long durations through training or education. By contrast, creativity as a dynamic state, particularly as a state that is subject to conscious augmentation within short time durations, has been less well-studied. Here, we tested the hypothesis that performance on a task of creative intelligence (creative analogical reasoning) can be improved through the deliberate effort to be creative. Specifically, we tested whether an explicit cue to “think creatively” would elicit better identification of creative analogies among 40 participants performing a four-term verbal analogical reasoning task. Consistent with our hypothesis, on creativity cue trials, the participants were 1) more likely to accurately identify highly creative analogies as valid, and 2) no more likely to inaccurately identify false analogies as valid. This pattern of results indicates that, consistent with a widely accepted standard for measuring creativity, the cue was successful in eliciting responses that were not only novel (divergent) but were also appropriate (bounded by task constraints). The findings show, in a within-subjects design, that deliberately attempting to augment creative state can enhance performance on a reasoning task with objective criteria. These findings are discussed with respect to the state vs. trait distinction in creativity and likely neural mechanisms of creative reasoning. [Copyright &y& Elsevier]

Abstract: The existence of general-purpose cognitive mechanisms related to intelligence, which appear to facilitate all forms of problem solving, conflicts with the strong modularity view of the mind espoused by some evolutionary psychologists. The current study assessed the contribution of general intelligence (g) to explaining variation in contextualized deductive reasoning. One hundred and twelve participants solved 70 contextualized reasoning problems in a computerized version of the Wason Card Selection Task that recorded both accuracy and reaction time. Consistent with prior research, in the sample as a whole, precautionary and social exchange reasoning problems were solved more frequently and more quickly than reasoning problems about arbitrary rules. At the individual-differences level of analysis, however, performance on all reasoning tests was significantly correlated and loaded on a single deductive-reasoning accuracy factor. Further, this factor was significantly correlated with g. There was no relation, however, between g and the speed of arriving at the correct answer for any form of deductive reasoning. We discuss the implications of these findings for evolutionary psychology, intelligence, and reasoning. [Copyright &y& Elsevier]