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Francis Sowerby Macaulay began his career working on Brill and Noether's theory of algebraic plane curves and their interpretation of the Riemann–Roch and Cayley–Bacharach theorems; in fact it is Macaulay who first stated and proved the modern form of the Cayley–Bacharach theorem. Later in his career Macaulay developed ideas and results that have become important in modern commutative algebra, such as the notions of unmixedness, perfection (the Cohen–Macaulay property), and super-perfection (the Gorenstein property), work that was appreciated by Emmy Noether and the people around her. He also discovered results that are now fundamental in the theory of linkage, but this work was forgotten and independently rediscovered much later. The name of a computer algebra program (now Macaulay2) recognizes that much of his work is based on examples created by refined computation. Though he never spoke of the connection, the threads of Macaulay's work lead directly from the problems on plane curves to his later theorems. In this paper we will explain what Macaulay did, and how his results are connected. [ABSTRACT FROM AUTHOR]

This Editorial reports an exchange in form of a comment and reply on the article "History and Nature of the Jeffreys–Lindley Paradox" (Arch Hist Exact Sci 77:25, 2023) by Eric-Jan Wagenmakers and Alexander Ly. [ABSTRACT FROM AUTHOR]

PsychoPy is an application for the creation of experiments in behavioral science (psychology, neuroscience, linguistics, etc.) with precise spatial control and timing of stimuli. It now provides a choice of interface; users can write scripts in Python if they choose, while those who prefer to construct experiments graphically can use the new Builder interface. Here we describe the features that have been added over the last 10 years of its development. The most notable addition has been that Builder interface, allowing users to create studies with minimal or no programming, while also allowing the insertion of Python code for maximal flexibility. We also present some of the other new features, including further stimulus options, asynchronous time-stamped hardware polling, and better support for open science and reproducibility. Tens of thousands of users now launch PsychoPy every month, and more than 90 people have contributed to the code. We discuss the current state of the project, as well as plans for the future. [ABSTRACT FROM AUTHOR]

Babesiosis, caused by piroplasmid protozoans in the genus Babesia, is arguably the most important vector-borne disease of livestock and companion animals and is growing in importance as a zoonosis. Ixodid ticks were identified as vectors more than a hundred years ago, but the particular tick species transmitting some significant pathogens are still unknown. Moreover, it is only recently that the complexity of the pathogen–tick relationship has been revealed as a result of studies enabled by gene expression and RNA interference methodology. In this article, we provide details of demonstrated and incriminated vectors, maps of the current knowledge of vector distribution, a summary of established features of the pathogen life cycle in the vector, and an outline of molecular research on pathogen–tick relationships. The article concludes with a discussion of vector ecology and disease epidemiology in a global-change context and with suggestions for future research. [ABSTRACT FROM AUTHOR]

The richness of biodiversity in the tropics compared to high-latitude parts of the world forms one of the most globally conspicuous patterns in biology, and yet few hypotheses aim to explain this phenomenon in terms of explicit microevolutionary mechanisms of speciation and extinction. We link population genetic processes of selection and adaptation to speciation and extinction by way of their interaction with environmental factors to drive global scale macroecological patterns. High-latitude regions are both cradle and grave with respect to species diversification. In particular, we point to a conceptual equivalence of 'environmental harshness' and 'hard selection' as eco-evolutionary drivers of local adaptation and ecological speciation. By describing how ecological speciation likely occurs more readily at high latitudes, with such nascent species especially prone to extinction by fusion, we derive the ephemeral ecological speciation hypothesis as an integrative mechanistic explanation for latitudinal gradients in species turnover and the net accumulation of biodiversity. [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]

Mathematicians use the word 'deep' to convey a high appreciation of a concept, theorem, or proof. This paper investigates the extent to which the term can be said to have an objective character by examining its first use in mathematics. It was a consequence of Gauss's work on number theory and the agreement among his successors that specific parts ofGauss's work were deep, on grounds that indicate that depth was a structural feature of mathematics for them. In contrast, French mathematicians had a less structural, more problem-oriented approach to mathematics and did not speak of depth so readily. [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]

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]

Although meditation is increasingly accepted as having personal benefits, less is known about the broader impact of meditation on social and intergroup relations. We tested the effect of lovingkindness meditation training on improving implicit attitudes toward members of 2 stigmatized social outgroups: Blacks and homeless people. Healthy non-Black, nonhomeless adults {N = 101) were randomly assigned to 1 of 3 conditions: 6-week lovingkindness practice, 6-week lovingkindness discussion (a closely matched active control), or waitlist control. Decreases in implicit bias against stigmatized outgroups (as measured by Implicit Association Test) were observed only in the lovingkindness practice condition. Reduced psychological stress mediated the effect of lovingkindness practice on implicit bias against homeless people, but it did not mediate the reduced bias against Black people. These results suggest that lovingkindness meditation can improve automatically activated, implicit attitudes toward stigmatized social groups and that this effect occurs through distinctive mechanisms for different stigmatized social groups. [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]

The study of intrapsychic conflict has long been central to many key theories about the control of behavior. More recently, by focusing on the nature of conflicting processes in the brain, investigators have revealed great insights about controlled versus automatic processes and the nature of self-control. Despite these advances, many theories of cognitive control or self-control remain agnostic about the function of subjective awareness (i.e., basic consciousness). Why people consciously experience some conflicts in the nervous system but not others remains a mystery. One hypothesis is that people become conscious only of conflicts involving competition for the control of skeletal muscle. To test one aspect of this larger hypothesis, in the present study, 14 participants were trained to introspect the feeling of conflict (the urge to make an error during a Stroop color-word interference task) and then were asked to introspect in the same way while sustaining simple compatible and incompatible intentions during fMRI scanning (to move a finger left or right). As predicted, merely sustaining incompatible skeletomotor intentions prior to their execution produced stronger systematic changes in subjective experience than sustaining compatible intentions, as indicated by self-report ratings obtained in the scanner. Similar ratings held for a modified Stroop-like task when contrasting incompatible versus compatible trials also during fMRI scanning. We use subjective ratings as the basis of parametric analyses of fMRI data, focusing a priori on the brain regions involved in action-related urges (e.g., parietal cortex) and cognitive control (e.g., dorsal anterior cingulate cortex, lateral PFC). The results showed that subjective conflict from sustaining incompatible intentions was consistently related to activity in the left post-central gyrus. [ABSTRACT FROM AUTHOR]

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]

The article focuses on the response of French mathematician Henri Poincaré to an address by German mathematician David Hilbert at the International Congress of Mathematicians (ICM) in 1908 in Rome, Italy. It is inferred that Hilbert attracted many talented students due to the mathematical problems presented at the ICM in Paris, France in 1900. An English translation of the lecture "The Future of Mathematics," by Poincaré at the ICM in 1908 is presented.

In sexual populations, gene-flow between niches is predicted to have differential consequences on local adaptation contingent upon the nature of trade-offs underlying local adaptation. Sex retards local adaptation if antagonistic pleiotropy underlies trade-offs, but facilitates adaptation if mutation accumulation underlies trade-offs. We evaluate the effect of sex in heterogeneous environments by manipulating gene-flow between two niches in sexual and asexual populations using steady-state microcosm experiments with yeast. We find that only sex in the presence of gene-flow promotes simultaneous local adaptation to different niches, presumably as this exposes mutations neutrally accrued in alternate niches to selection. This finding aligns with work showing mutation accumulation underlies trade-offs to local adaptation in asexual microbes, and with inferences of divergence in the presence of gene-flow in natural sexual populations. This experiment shows that sex may be of benefit in heterogeneous environments, and thus helps explain why sex has been maintained more generally. [ABSTRACT FROM AUTHOR]