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In this work, a power law f(Q)$f(Q)$ model is explored, specifically, f(Q)=αQn$f(Q)= \alpha Q^n$, along with viscous matter fluid having transport coefficient ζ=ζ0Ω+ζ1ΩH$\zeta = \zeta _0 \sqrt {\Omega } + \zeta _1 \Omega H$. The corresponding analytical solution is derived and then confronted with recent cosmic data. The Markov Chain Monte Carlo (MCMC) sampling technique is utilized to estimate the mean value of arbitrary parameters, by incorporating Cosmic Chronometers and recently published Pantheon+Analysis samples. In addition, some cosmological parameters are reconstructed by resampling the chains obtained by emcee, incorporating 6000 samples. It is found that the matter‐energy density depicts the expected positive behavior, whereas the effective pressure indicates the negative behavior that is leading the accelerating expansion, which is further predicted in the effective EoS parameter. Further, the asymptotic nature of the assumed model is investigated by invoking phase‐space analysis. It is concluded that the assumed viscous f(Q)$f(Q)$ model successfully predicts an evolution of the universe from decelerated epoch to stable accelerated de‐Sitter epoch. [ABSTRACT FROM AUTHOR]

We present a set of six time-temperature (tT) histories, called benchmark paths, that can be used as a shared framework for evaluating the sensitivity of a thermochronologic system to the variables inherent in the interpretation of thermochronologic data (e.g., kinetics models, mineral compositions or geometries, etc.). These benchmark paths span 100 Myr, include monotonic and nonmonotonic histories that represent plausible geologic scenarios, and have a range of cooling rates through different chronometer partial-retention/annealing temperatures. Here, we demonstrate their utility by presenting a method for tuning these paths to 11 different kinetics models for the apatite (U-Th-Sm)/He (n=5), apatite fission-track (n=2), and zircon (U-Th)/He (n=4) systems. These tuned tT paths provide a practical comparison of the kinetics models for each system and the data patterns they predict, thereby offering anyone performing thermal history analysis the ability to consider how their choice of kinetics model may impact their data interpretation. The adoption of benchmark paths for evaluating kinetics models and other variables provides a practical way for the thermochronology community to evaluate and communicate the decision making processes that are inherent in thermochronologic modeling and data interpretation. [ABSTRACT FROM AUTHOR]

This study investigates the accelerated cosmic expansion within the Hořava–Lifshitz (HL) Model. To constrain the cosmological parameters of this model, 17 Baryon Acoustic Oscillation points, 31 Cosmic Chronometer points, 40 Type Ia Supernovae points, 24 quasar Hubble diagram points, and 162 Gamma Ray Bursts points, along with the latest Hubble constant measurement (R22) are incorporated. rd$r_{d}$ is treated as a free parameter to extract H0$H_{0}$ and rd$r_{d}$ using late‐time datasets, aiming for optimal fitting values in each model. Treating rd$r_{d}$ as free improves precision, reduces bias, and enhances dataset compatibility. The obtained values of H0$H_{0}$ and rd$r_{d}$ are compared to the ΛCDM$\Lambda{\rm CDM}$ model, showing consistency with previous estimates from Planck and SDSS studies. The Akaike Information Criterion (AIC) and Bayesian Information Criterion (BIC) favor the Hořava–Lifshitz model, with the ΛCDM$\Lambda{\rm CDM}$ model having the lowest AIC. Additionally, ΔAIC$\Delta{\rm AIC}$ and ΔBIC$\Delta{\rm BIC}$ analyses are conducted to assess model preference. Validation using the reduced χred2$\chi _{red}^{2}$ statistic indicates satisfactory fits for the Hořava–Lifshitz model, while recognizing ΛCDM$\Lambda{\rm CDM}$ as the preferred model. Extensions of the analysis warrant further investigation. [ABSTRACT FROM AUTHOR]

This paper formulates a cooperative traffic control methodology that integrates traffic signal timing and ramp metering decisions into an optimization model to improve traffic operations in a corridor network. A mixed integer linear model is formulated and is solved in real time within a model predictive controller framework, where the cell transmission model is used as the system state predictor. The methodology is benchmarked in a case study corridor in San Mateo, CA, in VISSIM with two optimization scenarios, namely, optimal metering and optimal signal control, and two simulation scenarios with a preset metering plan and no metering. The numerical results show that integrated traffic signal and ramp metering control reduces delays, stops, and travel times of the corridor by up to 33.1%, 36%, and 16.4%, respectively, compared to existing benchmark conditions. With appropriate weights prioritizing freeway or arterial street operations, the integrated control balances traffic congestion between the arterial street and the freeway. [ABSTRACT FROM AUTHOR]

In order to alleviate the Hubble tension, we propose a new law for the Hubble parameter that varies periodically with time and we study the validity of the dynamics of a flat Friedmann–Robertson–Walker Universe in the context of a generalized Chern–Simons modified gravity (CSMG). We prove that for specific numerical values of the free parameters in the theory, the phantom divide line is crossed and the universe undergoes decelerating expansion and accelerating expansion alternately without singularity. The deceleration and the jerk parameters oscillate also around numerical values in agreement with astronomical BAO+Pantheon SNeIa+Cosmic Chronometers observations. [ABSTRACT FROM AUTHOR]

The Artemis exploration zone is a geologically complex region likely to host some of the oldest and as‐yet‐unstudied materials on the Moon. We review six potential Artemis landing sites (001, 004, 007, 011, 102, and 105) within candidate Artemis III landing regions "Connecting Ridge," "Peak Near Shackleton," "Leibnitz Beta Plateau," "de Gerlache Rim," and "de Gerlache Rim 2." Kaguya Spectral Profiler mineral data were used to determine the average lithological composition at each landing site. Potentially accessible geologic materials, their ages and significance, and appropriate application of radiometric chronometers are discussed in reference to return samples from each potential landing site. Chronological analyses of return samples from the Artemis exploration zone will enable the anchoring of the lunar impact flux curve, determine the absolute timing of pivotal events in lunar geologic history, and reveal the geological diversity of the differentiated lunar body. Plain Language Summary: Artemis astronauts will bring new samples from the Moon back to Earth. We discuss the geology of some landing sites that astronauts might visit, what types of rocks they may encounter, and how to examine them using geochronology. The application of geochronology to Moon rocks is essential to determine the absolute timing of major events in lunar and early Solar System history. Key Points: The Artemis lunar missions will explore a feldspathic impact terrain and return samples from unexplored terrainLikely lithologies, ages, and chronometers are discussed for six potential landing sitesArtemis return samples from the Moon will be unique from Apollo samples and have the possibility of determining absolute ages of significant events in lunar history [ABSTRACT FROM AUTHOR]

This paper explores the dynamic behavior of the universe within the framework of the f (R , G) theory of gravity. Here, R and G represent the Ricci scalar and Gauss–Bonnet invariant, respectively. By solving the modified field equations with the chosen f (R , G) function, specifically f (R , G) = R + m R 2 + n G 2 , we determine the best fit values of model parameters that are consistent with recent observational datasets. These datasets include 57 data points from the Cosmic Chronometers, Pantheon, and BAO datasets. Furthermore, we analyze the physical properties of cosmographic parameters, such as energy density and pressure, corresponding to the constrained values of the model parameters. The evolution of the deceleration parameter in our study indicates a transition from a decelerated phase to an accelerated phase in the universe. Remarkably, our f (R , G) cosmological model effectively describes the late-time cosmic acceleration without requiring the introduction of a dark energy component in the field equations. [ABSTRACT FROM AUTHOR]

In this study, we consider the Bianchi type I model in the framework of f (R , T) gravity theory. We solve the field equations with the help of an anisotropy parameter that can show the anisotropic behavior of the universe in the past and its approximation to isotropy today. For two different models, we examine the phase transition in the expansion of the universe by analyzing some cosmologic parameters. We conduct our investigation by applying the Markov Chain Monte-Carlo analysis and Bayesian technique to the Cosmic Chronometer, Phanteon and BAO datasets, taking into account the observational constraints on the parameters. We show that the two different models we obtained explain the transition from the slowing phase to the accelerating phase in the expansion of the universe, that the models behave in harmony with the Λ CDM model today, and that the current values of the cosmological parameters predicted by the models are compatible with the values indicated by the observations and we conclude that the Model-I is more compatible than the Model-II in this conformity. [ABSTRACT FROM AUTHOR]

We study the ion-irradiation-induced deformation of free-standing ultrathin Si wafers with a thickness of 8 μ m. The time-response spectrum of the deformation was measured using a laser displacement meter with a time resolution of 1 ms. The results showed that the deformation appeared during irradiation and disappeared after irradiation. The deformation was composed of a fast deformation with a millisecond time constant and a slow deformation with a second time constant. We performed a model calculation to identify the deformation mechanisms. We found that the fast deformation originated from expansion or shrinkage of crystal lattice caused by beam heating and deduced that the slow deformation resulted from the topological defect formation in Si crystals. The relaxation time of the slow deformation is related to the coordination number of disappeared topological defects. In this experiment, we conclude that the deformation of Si crystals maintains reversible behavior in the formation of topological defects up to the coordination number 5. [ABSTRACT FROM AUTHOR]

Using a fully Bayesian approach, Gaussian process regression is extended to include marginalization over the kernel choice and hyperparameters. In addition, Bayesian model comparison via the evidence enables direct kernel comparison. The calculation of the joint posterior was implemented with a transdimensional sampler which simultaneously samples over the discrete kernel choice and their hyperparameters by embedding these in a higher dimensional space, from which samples are taken using nested sampling. Kernel recovery and mean function inference were explored on synthetic data from exoplanet transit light-curve simulations. Subsequently, the method was extended to marginalization over mean functions and noise models and applied to the inference of the present-day Hubble parameter, H 0, from real measurements of the Hubble parameter as a function of redshift, derived from the cosmologically model-independent cosmic chronometer and lambda-cold dark matter-dependent baryon acoustic oscillation observations. The inferred H 0 values from the cosmic chronometers, baryon acoustic oscillations, and combined data sets are |$H_0= 66 \pm 6,\, 67 \pm 10,\, \mathrm{ and}\,69 \pm 6\,\mathrm{km}\, \mathrm{s}^{-1}\, \mathrm{Mpc}^{-1}$|⁠ , respectively. The kernel posterior of the cosmic chronometers data set prefers a non-stationary linear kernel. Finally, the data sets are shown to be not in tension with ln  R = 12.17 ± 0.02. [ABSTRACT FROM AUTHOR]

Accuracy and temporal resolution of flow meters are often unacceptable below the microliter per minute scale, limiting their ability to evaluate the real-time performance of many microfluidic devices. For conventional flow meters, this problem arises from uncertainties that depend on physical effects, such as evaporation, whose relative impacts scale inversely with flow rate. More advanced techniques that can measure nanoliter per minute flows are often not dynamic and require specialized equipment. Herein, we report on new experimental and theoretical results that overcome both limitations using an optofluidic flow meter. Previously, we showed that this device can measure flow rates as low as 1 nl/min with roughly 5% relative uncertainty by leveraging the photobleaching rate of a fluorescent dye. We now extend that work by determining the flow meter's relaxation time over a wide range of flow rates and incident irradiances. Using a simplified analytical model, we deduce that this time constant arises from the interplay between the photobleaching rate and transit time of the dye through the optical interrogation region. This motivates us to consider a more general model of the device, which, surprisingly, implies that all time constants are related by a simple scaling relationship depending only on the flow rate and optical irradiance. We experimentally validate this relationship to within 5% uncertainty down to 1 nl/min. Additionally, we measure a relaxation time of the flow meter on the order of 100 ms for 1 nl/min flows, demonstrating the ability to make dynamic measurements of small flows with unprecedented accuracy. [ABSTRACT FROM AUTHOR]

The paper studies different observational features in the case of a specific cubic gravity theory, based on third order contractions of the Riemann tensor. Considering viable cosmic chronometers data, baryon acoustic oscillations, and supernovae, we analyze the viability of such a theoretical model, obtaining specific constraints for different parameters in the current scenario. It is shown that the present extension of the Λ CDM cosmological model is compatible with recent data sets. The results indicate that the dark energy equation of state is exhibiting a phantom regime in the near past in the case of the best fitted values, a behavior which is in agreement with various phenomenological studies. [ABSTRACT FROM AUTHOR]

Recent attempts at measuring the variation of c using an assortment of standard candles and the redshift-dependent Hubble expansion rate inferred from the currently available catalogue of cosmic chronometers have tended to show that the speed of light appears to be constant, at least up to z ∼ 2. A notable exception is the use of high-redshift ultraviolet + X-ray quasars, whose Hubble diagram seems to indicate an ∼2.7σ deviation of c from its value c 0 (≡ 2.99792458 × 1010 cm s−1) on Earth. We show in this paper, however, that this anomaly is due to an error in the derived relation between the luminosity distance, D L, and H (z) when c is allowed to vary with redshift, and an imprecise calibration of the quasar catalogue. When these deficiencies are addressed correctly, one finds that c / c 0 = 0.95 ± 0.14 in the redshift range 0 ≲ z ≲ 2, fully consistent with zero variation within the measurement errors. [ABSTRACT FROM AUTHOR]

We present a novel approach to measuring the expansion rate and the geometry of the Universe, which combines time-delay cosmography in lens galaxy clusters with pure samples of 'cosmic chronometers' by probing the member galaxies. The former makes use of the measured time delays between the multiple images of time-varying sources strongly lensed by galaxy clusters, while the latter exploits the most massive and passive cluster member galaxies to measure the differential time evolution of the Universe. We applied two different statistical techniques, adopting realistic errors on the measured quantities, to assess the accuracy and the gain in precision on the values of the cosmological parameters. We demonstrate that the proposed combined method allows for a robust and accurate measurement of the value of the Hubble constant. In addition, this provides valuable information on the other cosmological parameters thanks to the complementarity between the two different probes in breaking parameter degeneracies. Finally, we showcased the immediate observational feasibility of the proposed joint method by taking advantage of the existing high-quality spectro-photometric data for several lens galaxy clusters. [ABSTRACT FROM AUTHOR]

Plots of daughter against parent concentration (D-P plots) are widely used as isotope ratio plots in geochronology. Their main purposes are: (1) to visualize the main ingredient of the radiometric age equation – the daughter-parent ratio – and (2) to inspect the daughter-parent relationship for anomalous behavior indicating influences of geological processes or analytical bias. Despite their benefits, D-P plots are currently not used for analyzing low-temperature thermochronology data. This contribution aims at putting D-P plots on the map as a data analysis tool. We present a simple, decision-tree-based classification for daughter-parent relationships that places a dataset into one of seven classes: linear relationship with zero intercept, cluster, linear relationship with systematic offset, non-linear relationship, several age populations, scattered data, and inverse relationship. Assigning a class to a dataset enables to choose further data analysis steps and the right algorithm to calculate a sample age, e.g. as pooled, central or isochron age, or a range of ages. We discuss how to deal with small sample sizes and the possibility of comparing data across samples and chronometers. Our simple classification scheme uses the information in the D-P plot for facilitating thermochronological data analysis and making it more consistent and traceable. [ABSTRACT FROM AUTHOR]

Marine chronometers, often considered precision instruments, proliferated in navigational practices during the nineteenth century. This paper examines their use in the hands of naval officers in the early-nineteenth century. It argues that both the instruments and their operators required careful management and regulation. In addition, officers learnt and adapted observatory practices relating to the process of data collection and management. Through these means, chronometric data was collected, organized, and reduced to negotiate accurate results. [ABSTRACT FROM AUTHOR]

Precision was not a quality expected from ordinary watches in the eighteenth century, which required specific maintenance to function correctly. The precautions to be taken to ensure the accuracy of pocket chronometers, whose going would influence navigation or the results of scientific activities, were even more vital. However, the remarkable attention that horological studies have devoted to the origins of chronometry has neglected these aspects. It has erroneously assumed that the success of chronometers was guaranteed by their innovative impact and technological advancement. To illustrate the importance to examine the birth of chronometry from the point of view of manipulating technology and the user experience, my paper will discuss the case of the small series of pocket chronometers manufactured between 1782 and 1794 by the London workshop of the Swiss watchmaker Josiah Emery. The article shows that not all the users possessed the necessary technical knowledge nor training to handle and employ chronometers appropriately and that the instructions given by the artisan to his clients played a fundamental role. [ABSTRACT FROM AUTHOR]

In the context of the Collaborative Materials Exercise CMX-7 organized by the Nuclear Forensics International Technical Working Group (ITWG), four sample of uranium materials were analysed by IFIN-HH, Romania. The presented work is focused on presenting the analytical process of adapting a SQ ICP-MS such that to be used for determining fingerprints of the nuclear materials of interest. The "in-house" protocol developed made possible the determination of the uranium isotopic ratio of the samples without the use of chemical separation and also to determine the concentration of the trace elements. The age determination calculated based on the 230Th/234U chronometer. [ABSTRACT FROM AUTHOR]

The formation of Carlin-type gold deposits is poorly constrained, mainly due to the lack of accurate ages for gold mineralization. The Youjiang basin, SW China, represents the world's second-largest Carlin-type gold province after NV, USA. In this paper, we use hydrothermal apatite U–Th–Pb dating to systemically determine the mineralization ages of five Carlin-type gold deposits, namely, Shuiyindong, Jinfeng, Zimudang, Linwang, and Jinya, in the Youjiang basin. The hydrothermal apatite is characterized by intimate intergrowth with gold-bearing sulfides, presence of primary fluid inclusions, irregular morphology and cathodoluminescence zoning, and MREE-enriched composition patterns, indicating that it is clearly associated and coeval with gold mineralization. The concentrations of lattice-bound U and Th in the apatite are highly variable, making it suitable for in situ secondary ion mass spectrometry (SIMS) U–Th–Pb dating. The dating results of hydrothermal apatite from the five deposits show that they formed at ca. 150–140 Ma, contemporary with the widespread felsic magmatism and associated W–Sn mineralization to the east of the Youjiang basin, probably in response to slab breakup of the Paleo-Pacific oceanic plate beneath the South China continental plate. Our case story suggests that hydrothermal apatite could be a robust chronometer for age dating of sedimentary rock-hosted gold mineralization worldwide. [ABSTRACT FROM AUTHOR]

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Problems with the concordance cosmology Λ CDM as the cosmological constant problem, coincidence problems and Hubble tension has led to many proposed alternatives, as the Λ (t) CDM, where the now called Λ cosmological term is allowed to vary due to an interaction with pressureless matter. Here, we analyze one class of these proposals, namely, Λ = α ′ a - 2 + β H 2 + λ ∗ , based on dimensional arguments. Using SNe Ia, cosmic chronometers data plus constraints on H 0 from SH0ES and Planck satellite, we constrain the free parameters of this class of models. By using the Planck prior over H 0 , we conclude that the λ ∗ term can not be discarded by this analysis, thereby disfavouring models only with the time-variable terms. The SH0ES prior over H 0 has an weak evidence in this direction. The subclasses of models with α ′ = 0 and with β = 0 can not be discarded by this analysis. Finally, by using distance priors from CMB, the Λ time-dependence was quite restricted. [ABSTRACT FROM AUTHOR]

We investigate the accelerated cosmic expansion in the late universe and derive constraints on the values of the cosmic key parameters according to different cosmologies such as Λ CDM, wCDM, and w 0 w a CDM. We select 24 baryon acoustic oscillation (BAO) uncorrelated measurements from the latest galaxy surveys measurements in the range of redshift z ∈ [ 0.106 , 2.33 ] combined with the Pantheon SNeIa dataset, the latest 33 H (z) measurements using the cosmic chronometers (CCs) method, and the recent Hubble constant value measurement measured by Riess 2022 (R22) as an additional prior. In the Λ CDM framework, the model fit yields Ω m = 0.268 ± 0.037 and Ω Λ = 0.726 ± 0.023 . Combining BAO with Pantheon plus the cosmic chronometers datasets we obtain H 0 = 69.76 ± 1.71 km s − 1 Mpc − 1 and the sound horizon result is r d = 145.88 ± 3.32 Mpc. For the flat wCDM model, we obtain w = − 1.001 ± 0.040 . For the dynamical evolution of the dark energy equation of state, w 0 w a CDM cosmology, we obtain w a = − 0.848 ± 0.180 . We apply the Akaike information criterion approach to compare the three models, and see that all cannot be ruled out from the latest observational measurements. [ABSTRACT FROM AUTHOR]

At the beginning of 19th century Ino Tadataka surveyed almost whole coast lines of Japanese Islands and main roads, and made 214 sheet maps of 1:36000 and 8 sheet maps of 1:216000 in scale. This paper deals with his map compilation and scale-down. method. Almost every night, if possible. Ino measured elevation angles of 20 to 30 stars crossing meridian to determine latitude. The Y coordinates of the observation points were calculated from the latitudes using the ratio that one degree difference in latitude was 28.2 ri (or 101.52×36000 sun). Here ri and sun are Japanese old measures. Ino could not measure longitude astronomically because he had not chronometer. He corrected coordinates (x,y) obtained in surface survey "Dosen-Ho", a kind of open traverse method. The X coordinates of the observation points were estimated as x Y/y. In this way, he obtained coordinates (X,Y) on scale of 1:36000 concerning approximately 1220 astronomical observation points in whole Japanese Islands. For the first step, he prepared local maps of 1:36000 from local surface survey, then corrected them by using the coordinates of astronomical observation points. For second step. he compiled the wide area maps of 1:36000 from local maps to control reference to the coordinates of observation points. The maps of 1: 216000 were compiled from the maps of 1:36000 by using the reduced coordinate values of one six. In this process, the coordinates of the observation points were referred to keep precision of the maps. [ABSTRACT FROM AUTHOR]

The current study aims at investigating a modified theory of gravity called f (G , T) theory. Our focus is on a Gauss-Bonnet cosmological model that integrates a non-linear Gauss-Bonnet term and a linear trace term. We assume f (G , T) = γ G m + 1 + n T , where γ , m and n represent free parameters. To solve the field equations, we employ a specialized formulation of the deceleration parameter, represented as q = α − β H , where α and β are model parameters. Consequently, we determine the optimal values of the model parameters by aligning them with the latest observational datasets, including 57 data points from the Cosmic Chronometers datasets, Pantheon datasets, and BAO datasets. Furthermore, we analyze the physical behavior of the cosmographic parameters corresponding to the constrained values of the model parameters, as well as energy density and pressure. The evolution of the deceleration parameter predicts a transition from the decelerated to the accelerated phases of the universe. Importantly, our f (G , T) cosmological model effectively describes the observed cosmic acceleration in the late-time universe, eliminating the need to introduce an additional dark energy component in the field equations. [ABSTRACT FROM AUTHOR]

Various interference reactions producing unwanted Ar isotopes from K, Ca, Cl and Ar require correction to satisfy the 40Ar/39Ar age equation. Using GEANT4, we design and build a model Cadmium Lined In Core Irradiation Tube (CLICIT) irradiation facility, as used in the Oregon State TRIGA Reactor (OSTR). We illustrate the complexity of the irradiation of geologic samples within this framework and determine an overlooked production channel of 36Ar. The production of 36Ar is fed from the 39K(n, α)36Cl nuclear channel, 36Cl subsequently decays to 36Ar (39K(n, α , β) 36Ar). Simulations in this work using a 235U fission neutron energy spectrum and modelled CLICIT facility, determine a production ratio for this reaction (36Cl/39Ar) K = 0.40 ± 0.01 (1 σ); greater than an order of magnitude larger than any other K interference. The magnitude of the resulting age bias for an unknown sample will be a function of the integrated neutron flux, the length of irradiation (fluence), the time elapsed since irradiation, and the age relationship between the unknown and neutron fluence monitor. We show using the raw data of (Niespolo et al., 2017) that the age of Alder Creek sanidine can be modified to be ca. 0.1% older (1 σ), at the 2σ level of current analytical precision for the Alder Creek age for this study. The 39K(n, α , β)36Ar inference should be incorporated into routine data analysis and may be especially important in the intercalibration of the 40Ar/39Ar system with other chronometers (e.g., 206Pb/238U). [ABSTRACT FROM AUTHOR]

The Hubble tension has now grown to a level of significance which can no longer be ignored and calls for a solution which, despite a huge number of attempts, has so far eluded us. Significant efforts in the literature have focused on early-time modifications of Λ CDM, introducing new physics operating prior to recombination and reducing the sound horizon. In this opinion paper I argue that early-time new physics alone will always fall short of fully solving the Hubble tension. I base my arguments on seven independent hints, related to (1) the ages of the oldest astrophysical objects, (2) considerations on the sound horizon-Hubble constant degeneracy directions in cosmological data, (3) the important role of cosmic chronometers, (4) a number of "descending trends" observed in a wide variety of low-redshift datasets, (5) the early integrated Sachs-Wolfe effect as an early-time consistency test of Λ CDM, (6) early-Universe physics insensitive and uncalibrated cosmic standard constraints on the matter density, and finally (7) equality wavenumber-based constraints on the Hubble constant from galaxy power spectrum measurements. I argue that a promising way forward should ultimately involve a combination of early- and late-time (but non-local—in a cosmological sense, i.e., at high redshift) new physics, as well as local (i.e., at z ∼ 0 ) new physics, and I conclude by providing reflections with regards to potentially interesting models which may also help with the S 8 tension. [ABSTRACT FROM AUTHOR]

We compared ruminal pH measurements determined using smaXtec bolus (SMAX; smaXtec Inc., Graf, Austria), Moonsyst bolus (MOON; Moonsyst International, Kinsale, Republic of Ireland), and handheld pH meter (METER; PH8500 pH/mV Meter, Apera, Columbus, OH) over time and during an ex vivo acidosis challenge. Ruminally cannulated heifers (n = 8) were used for 6 consecutive 21-d periods. On d 0, SMAX and MOON were placed in the reticulum of each heifer and continuously measured ruminal pH. On d 20 of each period, ruminal digesta samples were collected prior to feeding and again 2, 4, 6, 8, 12, 18, and 24 h post-feeding pH was measured with METER. MOON yielder lower (P < 0.01) pH measurements compared with SMAX and METER at all time points. From h 0 to 2 post-feeding measurements from SMAX were similar compared with METER (P = 0.54); however, measurements from SMAX tended to be greater 4 h post-feeding (P < 0.07) and differed at all subsequent timepoints (P < 0.05) compared with METER. On d 21 of each period, boli were removed and placed in a pH 4 and pH 7 solution, each for 3 h. In pH 4 solution, MOON pH measurements did not differ (P > 0.39) from 4 from periods 1 to 5; however, pH measured by MOON in period 6 was less (P < 0.01) than 4. Smaxtec pH measurements did not differ (P ≥ 0.39) from 4 during periods 2 to 5 but was greater (P < 0.01) than 4 in period 6. In pH 7 solution, pH measures with MOON did not differ (P > 0.26) from 7 for period 1 and 2 but declined in period 3 and were less than 7 from periods 4 to 6 (P < 0.05). In pH 7 solution, SMAX measurements varied over time and yielded greater (P < 0.05) than 7 for periods 2, 3, and 6. Subsequently, boli were placed in a container of strained ruminal fluid (6.5 L), and pH was measured for 1 h using SMAX, MOON, and METER. Following, 500 mL of vinegar was added to the ruminal fluid to simulate an acidosis challenge, pH was measured and change in pH detected by SMAX and MOON, relative to METER was determined. With change in pH detect by METER considered the true response, MOON provided a better measurement of the pH decrease than did SMAX, particularly during periods 1 to 3 (P < 0.01). Overall, pH measurements differed between SMAX, MOON, and METER. MOON and SMAX pH measurements began to drift after approximately 100 d. MOON was more accurate than SMAX in detecting a change in ruminal pH, whereas pH measurements over time were more precise for SMAX than for MOON. [ABSTRACT FROM AUTHOR]

We use the state-of-the-art data on cosmic chronometers (CCH) and the Pantheon+compilation of supernovae of Type Ia (SNIa) to test the constancy of the SNIa absolute magnitude, M , and the robustness of the cosmological principle (CP) at z ≲ 2 with a model-agnostic approach. We do so by reconstructing M (z) and the curvature parameter Ω k (z) using Gaussian Processes. Moreover, we use CCH in combination with data on baryon acoustic oscillations (BAO) from various galaxy surveys (6dFGS, BOSS, eBOSS, WiggleZ, DES Y3) to measure the sound horizon at the baryon-drag epoch, r d, from each BAO data point and check their consistency. Given the precision allowed by the CCH, we find that M (z), Ωk(z), and r d(z) are fully compatible (at |$\lt 68$| per cent C.L.) with constant values. This justifies our final analyses, in which we put constraints on these constant parameters under the validity of the CP, the metric description of gravity and standard physics in the vicinity of the stellar objects, but otherwise in a model-independent way. If we exclude the SNIa contained in the host galaxies employed by SH0ES, our results read |$M=(-19.314^{+0.086}_{-0.108})$|  mag, r d = (142.3 ± 5.3) Mpc, and |$\Omega _k=-0.07^{+0.12}_{-0.15}$|⁠ , with H 0 = (71.5 ± 3.1) km s−1 Mpc−1 (68 per cent C.L.). These values are independent of the main data sets involved in the H 0 tension, namely, the cosmic microwave background and the first two rungs of the cosmic distance ladder. If, instead, we also consider the SNIa in the host galaxies, calibrated with Cepheids, we measure |$M=(-19.252^{+0.024}_{-0.036})$|  mag, |$r_\mathrm{ d}=(141.9^{+5.6}_{-4.9})$| Mpc, |$\Omega _\mathrm{ k}=-0.10^{+0.12}_{-0.15}$|⁠ , and |$H_0=(74.0^{+0.9}_{-1.0})$|  km s−1 Mpc−1. [ABSTRACT FROM AUTHOR]

This paper studies the precise clock management technology for the power consumption information collection system which demands precise requirements of the electric power meter clock. The causes of the clock deviation of the collection system and the problems caused by the clock deviation are analysed first; Then the key technologies for achieving accurate time synchronization are explained; Next, the master station and terminal time synchronization algorithm is designed. Only two NLP synchronizations are required to obtain a high accuracy time deviation, and the accuracy of the algorithm is demonstrated through a test of an example. Finally, the electric power meter time adjustment scheme using a combination of broadcast time adjustment and ESAM point-to-point time adjustment is designed to achieve high accuracy and low error, which has high reliability and practicality. [ABSTRACT FROM AUTHOR]

f (T) cosmology has shown promise in explaining aspects of cosmic evolution. In this work, we analyse constraints on leading models of f (T) gravity in the context of the recently released Pantheon+ data set, together with comparisons with previous releases. We also consider other late time data sets including cosmic chronometers and baryonic acoustic oscillation data. Our main result is that we find that the different f (T) models under investigation connect to a variety of Hubble constant, which may help alleviate the cosmic tension on this parameter. [ABSTRACT FROM AUTHOR]

Objective: Arteriovenous fistula (AVF) operations are the most common method to facilitate hemodialysis in patients with chronic renal failure. The longevity of AVF is vital in patients undergoing hemodialysis. We investigated the effect of Transit Time Flow Meter (TTFM) use on AVF patency. Methods: 108 patients (42 in the study group, 66 in the control group) who underwent AVF formation for the first time in the last five years were included in the study. In the measurements made with TTFM, if the pulsatility index (PI) was >5 and the mean flow value was <30 mL/min, AVFs were considered insufficient. Results: Age, gender, lowdensity lipoprotein values (LDL), non-dominant extremity, and accompanying peripheral artery disease in the study group of patients were similar, and smoking in the study group and hypertension in the control group were the most common risk factors. PI and mean flow rates with TFTM in the study group were within the normal range. No statistically significant difference was found in the AVF patency rates when we compared the different periods between groups. However, when evaluating the AVF patency of the groups in the whole period, it was determined that the patency of the patients in the study group was better than the control, and this finding was statistically significant. Conclusion: Intraoperative use of TTFM helps detect AVF dysfunction. This method provides a longer vascular patency time. Increases patient comfort by prolonging the function and life of the AVF. [ABSTRACT FROM AUTHOR]

At least one dimensionless physical constant (i.e. a physically observable) must change for the cosmic time to make the varying speed of light (VSL) models phenomenologically feasible. Various physical constants and quantities also should be functions of cosmic time to satisfy all known local laws of physics, including special relativity, thermodynamics, and electromagnetism. Adiabaticity is another necessary condition to keep the homogeneity and isotropy of three-dimensional space. To be a self-consistent theory, one should consider cosmic evolutions of physical constants and quantities when one derives Einstein's field equations and their solutions. All these conditions are well-satisfied in the so-called minimally extended varying speed of light (meVSL) model. Unlike other VSL models, we show that the redshift-drift formula of the meVSL model is the same as a standard model. Therefore, we cannot use this as an experimental tool to verify the meVSL. Instead, one can still use the cosmological chronometers (CC) as a model-independent test of the meVSL. The current CC data cannot distinguish meVSL from the standard model (SM) when we adopt the best-fitting values (or Gaussian prior) of H 0 and Ω m 0 from the Planck mission. However, the CC data prefer the meVSL when we choose Pantheon22 data. [ABSTRACT FROM AUTHOR]

Eye lens core Δ14C of Gulf of Mexico outer shelf and upper slope reef fishes matched a regional Δ14C reference time series, but otolith cores were depleted in 14C relative to the reference series. This is due to C in eye lens protein being derived from metabolic sources, with the ultimate source being epipelagic phytoplankton. In contrast, otolith C is derived mainly (70%–80%) from dissolved inorganic C, which is depleted in 14C beyond the epipelagic. Analyzing Δ14C in eye lens cores provides a novel approach for validating age estimates of deepwater (>200 m) fishes, which were unresolved in earlier applications of the bomb 14C chronometer. [ABSTRACT FROM AUTHOR]

Local measurements of the Hubble constant ( H 0 ) based on Cepheids e Type Ia supernova differ by ≈ 5 σ from the estimated value of H 0 from Planck CMB observations under Λ CDM assumptions. In order to better understand this H 0 tension, the comparison of different methods of analysis will be fundamental to interpret the data sets provided by the next generation of surveys. In this paper, we deploy machine learning algorithms to measure the H 0 through a regression analysis on synthetic data of the expansion rate assuming different values of redshift and different levels of uncertainty. We compare the performance of different regression algorithms as Extra-Trees, Artificial Neural Network, Gradient Boosting, Support Vector Machines, and we find that the Support Vector Machine exhibits the best performance in terms of bias-variance tradeoff in most cases, showing itself a competitive cross-check to non-supervised regression methods such as Gaussian Processes. [ABSTRACT FROM AUTHOR]

The ages of the oldest stars shed light on the birth, chemical enrichment, and chemical evolution of the universe. Nucleocosmochronometry provides an avenue to determining the ages of these stars independent from stellar-evolution models. The uranium abundance, which can be determined for metal-poor r -process enhanced (RPE) stars, has been known to constitute one of the most robust chronometers known. So far, U abundance determination has used a single U ii line at λ 3859 Å. Consequently, U abundance has been reliably determined for only five RPE stars. Here, we present the first homogeneous U abundance analysis of four RPE stars using two novel U ii lines at λ 4050 Å and λ 4090 Å, in addition to the canonical λ 3859 Å line. We find that the U ii lines at λ 4050 Å and λ 4090 Å are reliable and render U abundances in agreement with the λ 3859 U abundance, for all of the stars. We, thus, determine revised U abundances for RPE stars, 2MASS J09544277+5246414, RAVE J203843.2–002333, HE 1523–0901, and CS 31082–001, using multiple U ii lines. We also provide nucleocosmochronometric ages of these stars based on the newly derived U, Th, and Eu abundances. The results of this study open up a new avenue to reliably and homogeneously determine U abundance for a significantly larger number of RPE stars. This will, in turn, enable robust constraints on the nucleocosmochronometric ages of RPE stars, which can be applied to understand the chemical enrichment and evolution in the early universe, especially of r -process elements. [ABSTRACT FROM AUTHOR]

"Earth summit mission 2022" is one of the landmark scientific research activities of the Second Tibetan Plateau Scientific Expedition and Research (STEP). This scientific expedition firstly used advanced technology and methods to detect vertical meteorological elements and produce forecasts for mountain climbing. The "Earth summit mission 2022" Qomolangma scientific expedition exceeded an altitude of over 8000 meters for the first time and carried out a comprehensive scientific investigation mission on the summit of Mt. Qomolangma. Among the participants, the westerly-monsoon synergy and influence team stationed in the Mt. Qomolangma region had two tasks: 1) detecting the vertical structure of the atmosphere for parameters such as wind, temperature, humidity, and pressure with advanced instruments for high-altitude detection at the Mt. Qomolangma base camp; and 2) observing extreme weather processes to ensure that members of the mountaineering team could successfully reach the top. Through this scientific expedition, a better understanding of the vertical structure and weather characteristics of the complex area of Mt. Qomolangma is gained. [ABSTRACT FROM AUTHOR]

The field of (U-Th)/He geochronology and thermochronology has grown enormously over the past ~25 years. The tool is applicable across much of geologic time, new (U-Th)/He chronometers are under continuous development, and the method is used in a diverse array of studies. Consequently, the technique has a rapidly expanding user base, and new labs are being established worldwide. This presents both opportunities and challenges. Currently there are no universally agreed-upon protocols for reporting measured (U-Th)/He data or data derivatives. Nor are there standardized practices for reporting He diffusion kinetic, 4He/³He, or continuous ramped heating data. Approaches for reporting uncertainties associated with all types of data also vary widely. Here, we address these issues. We review the fundamentals of the methods, the types of materials that can be dated, how data are acquired, the process and choices associated with data reduction, and make recommendations for data and uncertainty reporting. We advocate that both the primary measured and derived data be reported, along with statements of assumptions, appropriate references, and clear descriptions of the methods used to compute derived data from measured values. The adoption of more comprehensive and uniform approaches to data and uncertainty reporting will enable data to be re-reduced in the future with different interpretative contexts and data reduction methods, and will facilitate inter-comparison of data sets generated by different laboratories. Together, this will enhance the value, cross-disciplinary use, reliability, and ongoing development of (U-Th)/He chronology. [ABSTRACT FROM AUTHOR]

Precise visual time signals for marine chronometer rating began with a shuttered oil lamp in about 1823, but dropping time balls became the favoured visual signal for chronometer calibration. Electric time light signals became practicable in the twentieth century and replaced or complemented time balls as principal signals at various locations from 1909 onwards, with the first known implementations in Mozambique, China and Argentina. They were listed by the British Admiralty for 46 locations worldwide between 1911 and 1947. Not all existed together. There were 29 listed locations in Europe but none in the British Isles or North America. Their locations and types are described in this article, with specific details of signals outside Europe. They existed in extraordinary variety, ranging from coloured lights that replaced time balls in New Zealand to steady or flashing white lights at many other locations. All used the moment of extinction as the time signal. [ABSTRACT FROM AUTHOR]

During the early nineteenth century the Royal Observatory, Greenwich, significantly increased the number of individuals it employed. One of the new roles created was the position of First Assistant, who oversaw the management of astronomical labor at the observatory. This article examines the contribution of Robert Main, who was the first person employed in this role. It shows that, through Robert Main's duties and tasks, the observatory appears as a hybrid site embodying aspects of the other institutions that formed part of its operational network. Moreover, it demonstrates that the transformation of the observatory during the nineteenth century was driven by his rigorous maintenance of discipline in relation to the daily operations of the site. [ABSTRACT FROM AUTHOR]

Sm–Nd chronometers use 146 Sm and 147 Sm to determine the ages of major events in the early Solar System. Their half-lives are the most important nuclear parameters determining the accuracy of chronometry. However, the 146 Sm half-life is not well-established: the published values differ by ∼ 30%, which results in significant uncertainties in the Solar System timeline. We are re-measuring the half-lives of 146 Sm and 147 Sm using decay energy spectroscopy and metallic magnetic calorimeters to improve the accuracy of the Sm–Nd chronometers. We report recent experimental results from our first measurement of a 147 Sm source, as well as status and plans for experiments on 146 Sm. [ABSTRACT FROM AUTHOR]

Gray triggerfish (Balistes capriscus) historically have been aged by counting translucent zones in thin sections prepared from their first dorsal spine because their small, fragile sagittal otoliths are difficult to extract and process for ageing. However, recent research suggests dorsal spine translucent zone counts produce biased age estimates, thus the historical dorsal spine-based ageing protocol results in a systematic underestimation of true age. Here, we employed the bomb radiocarbon chronometer to test the accuracy of age estimates (n = 3 readers) derived from opaque zone counts in whole otoliths, as well as dorsal spine section translucent zone counts produced with the historical ageing protocol and a new method that requires higher magnification to count translucent zones on the margin of dorsal spine sections. Results indicate historical dorsal spine-derived age estimates underestimate age, with the extent of bias increasing with age. There was no evidence of ageing bias for both whole-otolith opaque zone counts and new protocol dorsal spine translucent zone counts. New dorsal spine protocol ageing was slightly more precise among readers (iAPE = 9.4 %) than otolith ageing (iAPE = 10.1 %) and read times were 2–3x faster for dorsal spine sections than whole otoliths. Validation of the new dorsal spine ageing protocol is a critical step in effective production ageing of gray triggerfish. Archived dorsal spine sections can be re-aged with the new protocol to update historical age composition data, and future ageing will not have to rely on the logistically challenging extraction and processing of otoliths. [ABSTRACT FROM AUTHOR]

Muscovite 40Ar/39Ar geochronology on ten samples from complex-type, rare-metal (e.g., Li, Cs, Ta, Rb, Be, Nb, Sn and W) pegmatites from the Bikita and Mweza pegmatite fields in Zimbabwe yield ages that range from ca. 2622 – 1940 Ma. One pegmatite from the Bikita field yield a relict age of ca. 2622 Ma which is similar to the ca. 2.62 Ga emplacement age of the Main Bikita Pegmatite previously determined by laser ablation analyses of Ta–Nb–Sn oxides. Younger muscovite 40Ar/39Ar ages of ca. 2580 – 2539 Ma in the Bikita field may reflect post-pegmatite emplacement tectono-thermal events under fluid-mediated conditions. Data from the Mweza pegmatite district yield dates of ca. 2027 – 1940 Ma which reflect a Palaeoproterozoic overprint. Palaeoproterozoic 40Ar/39Ar ages are spatially restricted to near the Northern Marginal Zone – Zimbabwe Craton boundary and are absent towards the interior of the craton in the Bikita pegmatite field. • Muscovite 40Ar/39Ar geochronology on rare-metal pegmatites from the Bikita & Mweza districts, Zimbabwe. • Re-set muscovite argon ages related to deformation and metamorphic episodes. • Multiple post-pegmatite emplacement tectono-thermal events along the southern margin of the Zimbabwe Craton. • Palaeoproterozic overprint of Neoarchaean muscovite ages under fluid-mediated conditions. • Muscovite argon geochronology complements other mineral chronometers in elucidating regional tectonic events. [ABSTRACT FROM AUTHOR]

In 1915 while the Imperial Trans-Antarctic Expedition's vessel Endurance was icebound in the Weddell Sea, lunar occultation timings were carried out in order to rate the chronometers and thereby find longitude. The original observations have been re-analysed using modern lunar ephemerides and catalogues of star positions. The times derived in this way are found to differ by an average of 20 s from those obtained during the expedition using positions given from the Nautical Almanac and introduces an additional offset of the true positions to the east of those recorded in the log. [ABSTRACT FROM AUTHOR]

Advances in low-temperature thermochronology, and the wide range of geologic problems that it is used to investigate, have prompted the routine use of thermal history (time-temperature, tT) models to quantitatively explore and evaluate rock cooling ages. As a result, studies that investigate topics ranging from Proterozoic tectonics to Pleistocene erosion now commonly require a substantial numerical modeling effort that combines the empirical understanding of chronometer thermochemical behavior (kinetics) with independent knowledge or hypotheses about a study area's geologic history (geologic constraints). Although relatively user-friendly programs, such as HeFTy and QTQt, are available to facilitate thermal history modeling, there is a critical need to provide the geoscience community with more accessible entry points for using these tools. This contribution addresses this need by offering an explicit discussion of modeling strategies in the program HeFTy. Using both synthetic data and real examples, we illustrate the opportunities and limitations of thermal history modeling. We highlight the importance of testing the sensitivity of model results to model design choices and describe a strategy for classifying model results that we call the Path Family Approach. More broadly, we demonstrate how HeFTy can be used to build an intuitive understanding of the thermochronologic data types and model design strategies that are capable of discriminating among geologic hypotheses. [ABSTRACT FROM AUTHOR]