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Virtual reality (VR) and 360° video can provide new opportunities for testing and training in sport. Both options offer different benefits in terms of efficacy for training, ease of use, and cost. This creates questions about the implementation of immersive technologies, and research is required to further understand their use. We aimed to gain initial evidence of athletes' perceptions of face validity and fidelity in VR and 360-video. Thirty-nine international pathway cricketers experienced five overs in VR cricket and in a 360-video recording. After trying each technology, players completed questionnaires to measure perceptions of presence and task workload. Participants reported immersive experience in both methods, but higher levels of realism, possibility to act, physical effort, temporal constraints, and task control in VR. 360-video offers a better possibility to visually examine the environment, while VR offers enhanced realism and physical elements, but 360-video may still offer affordable solutions for visual tasks. [ABSTRACT FROM AUTHOR]

Claims that Herodotus reveals himself as a proto-biographer, let alone as a proto-feminist, are not yet widely accepted. To help advance these claims, I have selected one remarkable, non-Greek, barbarian woman—Queen Atossa of Persia, the daughter of Cyrus the Great, and the spouse of three Achaemenid kings—whose exploits during their reigns are recounted in his Histories. It is to Heraclitus—a near contemporary—to whom we attribute the maxim êthos anthropôi daimôn (ἦθος ἀνθρώπῳ δαίμων)—character is human destiny—and it is the truth of this maxim—implying effective human agency—that makes Herodotus’ creation of historical narrative possible. From his many vignettes, which, without advancing the narrative, Herodotus is able to color-in the character of some of the more notable individuals he identifies in his Histories. Although never the cradle to grave accounts typical of Plutarch centuries later, by leap-frogging through three of the nine books, we can assemble a partially continuous narrative, and thus gauge Atossa’s character. Arguably this lets us attribute both credit and moral responsibility. This implied causation demonstrates that Herodotus’ writings include not only proto-biography but in several instances—one of which is given here—proto-feminism.

Background: Joint-preserving hip operations can help relieve pain and delay the need for long-term joint arthroplasty. Previous research has not identified procedures that can compromise outcomes following total hip arthroplasty (THA). This meta-analysis aims to evaluate the effect of joint-preserving hip operations on outcomes following subsequent THA. Methods: MEDLINE, EMBASE and Scopus databases were searched from the date of inception until February 2024. All studies comparing outcomes following THA in individuals with (PS) and without prior surgery (NPS) of the femur or pelvis were included. Data on operative time, blood loss, intra- and post-operative complications, functional outcomes, and implant survivorship were extracted. Results: 16 studies, comprising 2576 patients were included (PS = 939, NPS = 1637). The PS group was associated with significantly longer operative time [MD: 8.1, 95% CI: 4.6–11.6], significantly greater blood loss [MD: 167.8, 95% CI: 135.6–200.0], and a higher risk of intra-operative peri-prosthetic fracture [RR: 1.9, 95% CI: 1.2–3.0], specifically, with prior femoral osteotomy. There were no differences in terms of risks of dislocation [RR: 1.8, 95% CI: 1.0–3.2], implant loosening [RR: 1.0, 95% CI: 0.7–1.5], or revision surgery [RR: 1.3, 95% CI: 1.0–1.7] between the two groups. The PS group was associated with significantly poorer improvements in functional outcome [MD: −5.6, 95% CI: −7.6–(−3.5)], specifically, with prior acetabular osteotomy. Implant survivorship in the two groups was comparable after one year [HR: 1.9, 95% CI: 0.6–6.2] but significantly inferior in the PS group after five years [HR: 2.5, 95% CI: 1.4–4.7], specifically, with prior femoral osteotomy. Conclusion: Joint-preserving hip operations are associated with greater intra-operative challenges and complications. In subsequent joint arthroplasty, prior acetabular procedures affect functional outcomes while prior femoral procedures influence implant survivorship. Hip pain due to the morphological sequelae of pediatric hip pathology can be debilitating at a young age. Surgical decision-making at that time needs to consider the survivorship of a THA implanted at that young age against the consequences of hip preservation surgery on further THA.

Mitochondria and oxidative metabolism are critical for maintaining cardiac muscle function. Research has shown that mitochondrial dysfunction is an important contributing factor to impaired cardiac function found in heart failure. By contrast, restoring defective mitochondrial function may have beneficial effects to improve cardiac function in the failing heart. Therefore, studying the regulatory mechanisms and identifying novel regulators for mitochondrial function could provide insight which could be used to develop new therapeutic targets for treating heart disease. Here, cardiac myocyte mitochondrial respiration is analyzed using a unique cell culture system. First, a protocol has been optimized to rapidly isolate and culture high viability neonatal mouse cardiomyocytes. Then, a 96-well format extracellular flux analyzer is used to assess the oxygen consumption rate of these cardiomyocytes. For this protocol, we optimized seeding conditions and demonstrated that neonatal mouse cardiomyocytes oxygen consumption rate can be easily assessed in an extracellular flux analyzer. Finally, we note that our protocol can be applied to a larger culture size and other studies, such as intracellular signaling and contractile function analysis.

Herodotus comes down to us as the father of history and his fifth-century work, the Histories, is recognized as the first in an entirely new literary genre. But mid-fifth-century historiography is missing one of the most convenient of supranational tools—a reliable dating grid, or calendar—and Herodotus simply must make do as best he can without one. Although it was first suggested by a sixth-century Scythian monk, the axis of time along the now familiar BC/AD system is of comparatively recent adoption. Partly because of bitter doctrinal disputes over when Jesus of Nazareth was born—this system is never widely accepted until a seventeenth-century Jesuit scholar suggests that Anno Domini year one is just a convenient convention and by no means an agreement. When reading Herodotus today, particularly in an annotated edition in translation providing scholarly estimates of the Julian dates for the events under discussion, it is only too easy to be blissfully unaware of the author’s extreme dating handicap

Temperature gradients induce mass separation in mixtures in a process called thermal diffusion and are quantified by the Soret coefficient ST. Thermal diffusion in fluid mixtures has been interpreted recently in terms of the so-called (pseudo-)isotopic Soret effect but only considering the mass and moment of inertia differences of the molecules. We demonstrate that the first moment of the molecular mass distribution, the mass dipole, contributes significantly to the isotopic Soret effect. To probe this physical effect, we investigate fluid mixtures consisting of rigid linear molecules that differ only by the first moment of their mass distributions. We demonstrate that such mixtures have non-zero Soret coefficients in contrast with ST = 0 predicted by current formulations. For the isotopic mixtures investigated in this work, the dependence of ST on the mass dipole arises mainly through the thermal diffusion coefficient DT. In turn, DT is correlated with the dependence of the molecular librational modes on the mass dipole. We examine the interplay of the mass dipole and the moment of inertia in defining the isotopic Soret effect and propose empirical equations that include the mass dipole contribution. [ABSTRACT FROM AUTHOR]

Abstract We are in the midst of a revolution in satellite technology, with the rapid development and advancement of small satellites (or SmallSats, i.e., satellites

Background: Dismounted military operations require soldiers to complete cognitive tasks whilst undertaking demanding and repeated physical taskings. Objective: To assess the effects of repeated fast load carriage bouts on cognitive performance, perceptual responses, and psychophysiological markers. Methods: Twelve civilian males (age, 28 ± 8 y; stature, 186 ± 6 cm; body mass 84.3 ± 11.1 kg; V̇O2max, 51.5 ± 6.4 mL·kg−1·min−1) completed three ∼65-min bouts of a Fast Load Carriage Protocol (FLCP), each interspersed with a 65-min recovery period, carrying a representative combat load of 25 kg. During each FLCP, cognitive function was assessed using a Shoot/Don't-Shoot Task (SDST) and a Military-Specific Auditory N-Back Task (MSANT), along with subjective ratings. Additional psychophysiological markers (heart rate variability, salivary cortisol, and dehydroepiandrosterone-sulfate concentrations) were also measured. Results: A main effect of bout on MSANT combined score metric (p <.001, Kendall's W = 69.084) and for time on the accuracy-speed trade-off parameter of the SDST (p =.025, Ѡ2 =.024) was evident. These likely changes in cognitive performance were coupled with subjective data indicating that participants perceived that they increased their mental effort to maintain cognitive performance (bout: p <.001, Ѡ2 =.045; time: p <.001, Ѡ2 =.232). Changes in HRV and salivary markers were also evident, likely tracking increased stress. Conclusion: Despite the increase in physiological and psychological stress, cognitive performance was largely maintained; purportedly a result of increased mental effort. Application: Given the likely increase in dual-task interference in the field environment compared with the laboratory, military commanders should seek approaches to manage cognitive load where possible, to maintain soldier performance. [ABSTRACT FROM AUTHOR]

This study investigates the rapid weight loss (RWL) and rapid weight gain (RWG) of contest winners and losers from Muay Thai (MT) and mixed martial arts (MMA) events. The relationship between rapid weight change variables of males and females, and competitive success is also examined. Data from a weight management questionnaire was collected one day post-competition from 185 participants across 24 fight events, resulting in 263 responses (MMA: n = 78, MT: n = 185). Official and secondary weigh-in data were provided by the Combat Sports Commission. The results show that in MT, contest winners compared to losers had significantly greater RWL–7 days (5.9 ± 2.6% vs. 4.6 ± 2.7%, p = 0.01), RWG (6.2 ± 2.9% vs. 4.7 ± 2.8%, p = 0.003), and RWG/RWL ratio (108% [86–132%] vs. 86% [60–119%], p = 0.038), while no significant differences were observed for MMA. Mixed logistic regression models that controlled for age showed that a 1% increase in female RWL–24 h ([OR = 1.57, R2 = 0.105, p = 0.001]) was associated with a 1.6 times higher likelihood of winning compared to female athletes without this increase. We emphasise that associations do not imply causation, and it is possible that other factors which align with rapid weight change practices may impact the observed relationship. Nonetheless, MT contest winners show greater RWL, RWG, and RWG/RWL ratio than losers, and female rapid weight changes appear to be associated with competitive success in this cohort. [ABSTRACT FROM AUTHOR]

An E. coli cell contains ~2500 different chemicals which combine into an ordered biochemical reaction network out of which emerges a living system. A chemist taking 2500 different chemicals from a laboratory chemical cabinet and combining them together will likely cause an explosive disaster and produce an intractable chemical sludge. Systems Chemistry aspires to construct systems whose complexity rivals that of life. However, to do this we will need to learn how to combine hundreds or thousands of different chemicals together to form a functional system without descending into a disordered chemical sludge. This is the Many‐Chemicals Problem of Systems Chemistry. I explore a key strategy life employs to overcome this challenge. Namely, the combination of kinetically stable and thermodynamically activated molecules (e. g. ATP) with enzyme catalysts (e. g. histidine kinases). I suggest how the strategy could have begun at the origin of life. Finally, I assess the implications of this strategy for Systems Chemistry and how it will enable systems chemists to construct systems whose complexity rivals that of life. [ABSTRACT FROM AUTHOR]

We synthesize knowledge from numerical weather prediction, inverse theory, and statistics to address the problem of estimating a high‐dimensional covariance matrix from a small number of samples. This problem is fundamental in statistics, machine learning/artificial intelligence, and in modern Earth science. We create several new adaptive methods for high‐dimensional covariance estimation, but one method, which we call Noise‐Informed Covariance Estimation (NICE), stands out because it has three important properties: (a) NICE is conceptually simple and computationally efficient; (b) NICE guarantees symmetric positive semi‐definite covariance estimates; and (c) NICE is largely tuning‐free. We illustrate the use of NICE on a large set of Earth science–inspired numerical examples, including cycling data assimilation, inversion of geophysical field data, and training of feed‐forward neural networks with time‐averaged data from a chaotic dynamical system. Our theory, heuristics and numerical tests suggest that NICE may indeed be a viable option for high‐dimensional covariance estimation in many Earth science problems. Plain Language Summary: Models of physical processes must be fitted to real‐world data before they are useful for prediction. In some cases, the most practical way to fit models to data is to run a set—or ensemble—of simulations with different physics or initial conditions. One then uses the covariances among the inputs and outputs to modify the simulations so that they fit the data better. To reduce noise in the covariances, one ideally uses an ensemble size that is larger than the number of unknown variables, but this becomes impractical when the number of unknowns is large. To improve the performance of this fitting process when the ensemble size is small, one can discount covariances between variables that are likely due to noise. We introduce several methods of covariance estimation that determine the degree to which covariances are discounted based on expected levels of noise. All new methods perform well on a series of Earth science–inspired problems, but we highlight one method that preserves a key property of covariance matrices at a low computational cost. Key Points: We introduce several methods of covariance matrix estimation that adaptively select regularization parameters based on estimates of sampling errorOne method, Noise‐Informed Covariance Estimation, stands out because it guarantees a positive semi‐definite estimator at a low computational costAll new covariance estimation methods perform well on a large variety of test problems [ABSTRACT FROM AUTHOR]

Claims that Herodotus reveals himself as a proto-biographer, let alone as a proto-feminist, are not yet widely accepted. To advance these claims, I have selected one remarkable woman from one side of the Greco-Persian Wars whose activities are recounted in his Histories. Critically it is to a near contemporary, Heraclitus, to whom we attribute the maxim êthos anthropôi daimôn (ἦθος ἀνθρώπῳ δαίμων) —character is human destiny. It is the truth of this maxim—which implies effective human agency—that makes Herodotus’ creation of historical narrative even possible. Herodotus is often read for his vignettes, which, without advancing the narrative, color-in the character of the individuals he depicts in his Histories. No matter, if these fall short of the cradle to grave accounts given by Plutarch, by hop-scotching through the nine books, we can assemble a partially continuous narrative, and thus through their exploits, gauge their character, permitting us to attribute both credit and moral responsibility. Arguably this implied causation demonstrates that Herodotus’ writings include much that amounts to proto-biography and in several instances—one of which is given here—proto-feminism.