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Nanopores with an Engineered Selective Entropic Gate Detect Proteins at Nanomolar Concentration in Complex Biological Sample
Retraction: Multiliteracies meet new methods: The case for digital writing in English education case study in G-7 countries
Optimization of the gantry drive through dynamic testing and comparison with the crankset in a pilot study
Abstract The aim of the research was to conduct a pilot optimization of the gantry drive with a swinging pressure plate, which resembles the leg press exercise, using dynamic tests and to gather users’ opinions about this new drive. Moreover, the efficiency of the gantry drive was compared with the commonly known crankset. The research was conducted at a load of 50 W on a group of young men, and the results were subjected to statistical analysis. The research has shown that the gantry drive with guides mounted at a positive angle provides the highest efficiency, and users evaluated this mechanism positively despite their first encounter with it. Additionally, it has been shown that in terms of efficiency, when operating at low power, the gantry drive is generally similar to the crankset. The gantry drive takes up less volume than the crankset, making it well-suited for compact road vehicles and advantageous for water vehicles as well.
Two-dimensional infrared spectroscopy using a fast-scanning interferometer and chirped pulse upconversion at 100 kHz
We report on a 100-kHz two-dimensional infrared (2DIR) spectrometer in the pump–probe geometry, which we apply to the measurement of the 2DIR spectrum of carboxyhemoglobin. The probe pulses are spectrally resolved by chirped-pulse upconversion (CPU) using a fast 2048-pixel line scan CMOS camera. The two-pulse pump sequence is generated using a conventional interferometer with a fast-scanning mechanical delay line allowing to achieve a scanning frequency of 2 Hz. The resulting modulation frequency of 3.1 kHz is large enough to shift the relevant signal away from the low-frequency noise of the laser source. The combined use of an interferometer on the pump side and of CPU on the probe side opens the way to an improved spectral resolution in both pump and probe dimensions, as compared to currently available 100-kHz 2DIR spectrometers based on pulse shapers and mercury–cadmium telluride detector arrays.
Catalytic Metalloradical System for Radical 1,6-C(sp<sup>3</sup>)–H Amination with Concurrent Control of Site-, Chemo-, and Enantio-selectivity
Prognostic and predictive value of IDO expression in metastatic melanoma treated with Ipilimumab
Background The tumor microenvironment is crucial for prognosis and response to immunotherapy in several tumor entities. Methods In a multicenter retrospective study, a total of 86 tumor samples from patients with metastatic melanoma were evaluated for baseline expression of indoleamine 2,3-dioxygenase (IDO) and programmed death ligand 1 (PD-L1). Expression patterns of IDO and PD-L1 on tumor cells and antigen-presenting cells (APCs) as determined by immunohistochemical (IHC) staining of paraffin-embedded tissue sections were correlated with response to ipilimumab and overall survival (OS). Statistical analysis was performed using the Spearman correlation, the Mann-Whitney test and Kaplan-Meier estimator. Results IDO expression in tumor cells or APCs was not predictive for treatment response. The median OS was 26 months in IDO-positive and IDO-negative patients, regardless of IDO expression in tumor cells or APCs. A correlation of IHC expression scores of IDO and PD-L1 could not be documented. Conclusion The exact role of IDO in creating an immunosuppressive tumor environment and its reversal needs to be further elucidated.
Coupling analysis of multiple risk factors in deep foundation pit construction of metro station based on the N-K/SNA model
Elastic and exchanged atom–molecule collisions in 4He–4He–X (X = 40K, 85Rb, 133Cs) systems at low energy
We investigate the low-energy collision properties of the 4He–4He–X (X = 40K, 85Rb, 133Cs) systems using the R-matrix propagation method within the hyperspherical coordinate framework. The atom–dimer scattering length and atom–molecule collisional exchange rates are derived by solving the three-body Schrödinger equation using a potential energy surface obtained by summing three realistic pairwise potentials. Our results show that the atom–molecule collision exchange rates in the 4He2 + X → 4HeX + 4He process are primarily governed by the 4HeX two-body scattering lengths. Furthermore, when scaled by this parameter, the inelastic cross sections for all three systems collapse onto a single curve, demonstrating universal behavior. These findings provide new insights into the fundamental properties of weakly bound helium–helium–alkali-metal systems and their role in low-energy three-body collisions.
Two-Stage Solvation of Lithium Polysulfides in Working Lithium–Sulfur Batteries
A contemporary tool for assessing instrumental activities of daily living: Validation of a caregiver-reported scale for non-institutionalized older adults
Background Instrumental activities of daily living (IADL) refer to activities necessary for independent living, emphasizing community-related tasks. The literature has limited measurement tools that address autonomous living in contemporary communities. Consequently, our study aimed to develop, cross-culturally adapt, and evaluate the psychometric properties of a recently updated IADL scale called the Autonomy in Daily Functioning-Contemporary Scale (ADF-CS). Additionally, it sought to examine the level of agreement between informant reports and self-reports on the ADF-CS. Method Following translation and cross-cultural adaptation, a first cross-sectional study was carried out among 544 family caregivers of community-dwelling older adults to assess the psychometric properties of the ADF-CS. The internal consistency of the scale was evaluated via Cronbach’s alpha. Content and convergent validity, factorial analysis—including confirmatory factor analysis (CFA) and exploratory factor analysis (EFA)—and known group validity were also assessed. A second cross-sectional study involving 44 paired caregivers and care recipients was conducted to examine the level of agreement in responses to the ADF-CS scale between caregivers and older adults. Response agreement was evaluated through intraclass and Cohen’s kappa correlation coefficients. Results The internal consistency of the ADF-CS and its factors was high (Cronbach’s alpha between 0.83 and 0.90). The robust positive correlation between the total ADF-CS score and the ADL score supported the convergent validity of the ADF-CS Arabic version. Moreover, the statistically significant variations in ADF-CS mean scores among various age groups and some chronic disease groups supported the scale’s known group validity. The EFA of the ADF-CS yielded a two-factor solution with an eigenvalue exceeding 1, explaining 63.13% of the variance. The CFA demonstrated that all the items in each component fit well with their intended constructs. Additionally, the intraclass and kappa correlation coefficient results were excellent, indicating robust agreement in the responses of caregivers and their respective older adults. Conclusion The Arabic version of the ADF-CS is a reliable and valid informant-reported measure for assessing IADL in older adults living in a contemporary community.
Establishing a periodic SM model with Fourier analysis for enhancing global soil moisture forecasting
Ultrafast vibrational spectroscopic analysis of the ubiquitous precatalyst [Mn2(CO)10] in different solvents
Infrared (IR) absorption and time resolved IR (IRpump–IRprobe, 2D-IR) spectroscopies have been combined to study the vibrational dynamics and solvent interactions of the carbonyl ligand stretching vibrational modes of the photocatalyst dimanganese decacarbonyl, [Mn2(CO)10], in solvents with varying physical properties (heptane, cyclohexane, THF, MeCN, DMSO, iPrOH, and MeOH). The presence of a solvent-mediated symmetry breaking mechanism leading to a gain in oscillator strength of formally symmetry-forbidden modes was observed in all solvents, although the effect was more marked in polar solvents. Ultrafast vibrational energy dissipation was found to occur via two solvent dependent relaxation pathways, rapid intramolecular vibrational energy redistribution (IVR ∼ 0.3–1 ps) and relaxation to the ground vibrational state (T1 ∼ 80–250 ps). Accelerating factors for vibrational relaxation included hydrogen bonding and the presence of solvent vibrational modes resonant with the carbonyl modes of [Mn2(CO)10], while IVR timescales displayed an anticorrelation with vibrational relaxation times. Overall, a simple association of dynamic behavior with solvent properties could not be identified for any of the measured parameters. Rather, specific solvent properties were found to contribute to different extents in each case. Thus, our results highlight the need for careful consideration of solvent factors when attempting a rational selection of catalyst/solvent combinations or the implementation of sustainable replacement solvents.
3000 yr-old patterns of mobile pastoralism revealed by multiple isotopes and radiocarbon dating of ancient horses from the Mongolian Altai
Pastoral nomadism is of great cultural and economic importance in several regions of the world today. However, documenting ancient patterns of mobility in societies where pastoralism was central is challenging and requires tailored approaches and methodologies. Here we use strontium, oxygen and carbon isotopic analyses of dental enamel, together with a local strontium isoscape, to reconstruct the mobility patterns of seven domestic horses deposited in a Late Bronze Age grave from western Mongolia. Radiocarbon indicates that the animals were deposited within a short period of time, 3000 years ago. The isotope time series obtained from tooth enamel shows that four of the seven horses exhibited a common pattern characterized by a high frequency of mobility, suggesting that in this area (1) cyclical pastoral mobility dates back at least to the Late Bronze Age and (2) the animals belonged to the same herding family, implying that only a small community was involved in the funerary rite of this structure. The data show that the other three horse individuals had a distinct mobility pattern and that one was not from the local area, pointing to flexibility in mobility patterns over time or circulation of animals between herding groups. These results illustrate the power of the isotopic approach to reconstruct animal biographies and effectively address the archaeology of pastoral nomadism and mobility.
Balance level of elite amputee football players
Double-quantum two-dimensional electronic–vibrational spectroscopy: Theory. Vibronic coherences in nonadiabatic phenomena
Nonadiabatic phenomena are ubiquitous in polyatomic molecular systems and are responsible for many ultrafast dynamics occurring outside of the Born–Oppenheimer approximation. In particular, electronic curve crossings offer ultrafast, sub-100 fs pathways for efficient electronic relaxation between potential energy surfaces, where the electronic and vibrational degrees of freedom become strongly coupled. Due to the unique mixture of temporal and spectral resolution required to detect electronic curve crossings, experimental observation has remained a considerable challenge. Here, double-quantum coherence two-dimensional electronic–vibrational (2Q 2D EV) spectroscopy is introduced for the first time and proposed as an experimental approach to monitor vibronic dynamics near and at electronic curve crossings directly through vibronic coherences using a mixture of broadband visible and infrared pulses. A semi-classical vibronic Hamiltonian is used that characterizes the parametrically defined coupling between high-frequency vibrations and low-frequency vibrational modes involved in tuning electronic potential energy surfaces. This work displays how unique multidimensional pulse sequences can uncover dynamics that are hidden in conventional techniques.
Iron-Catalyzed Transfer Hydroalumination of Alkynes
Socioeconomic inequalities in Chile during the COVID-19 pandemic: A regional analysis of income poverty
The COVID-19 pandemic caused an unprecedented economic crisis, intensifying poverty levels in Latin America, particularly in Chile. This study examines the short- and long-term socioeconomic impacts of COVID-19 on income poverty in Chile, focusing on regional disparities, rurality, ethnicity, educational attainment, and immigration. Using data from the Chile National Socioeconomic Characterization Survey (CASEN) for 2017, 2020, and 2022, we analyzed poverty trends across the pre-pandemic, pandemic, and post-pandemic periods. We employed spatial clustering techniques with Local Moran’s I to detect poverty hotspots and applied logistic regression models to identify key sociodemographic factors associated with these hotspots. Our results reveal stark regional disparities, with disproportionately higher poverty rates among rural populations, Indigenous communities, and individuals with lower education levels or immigrant backgrounds. The proportion of individuals in poverty hotspots rose from 6.8% in 2017 to 8.6% in 2020, before slightly declining to 7.7% in 2022. Although emergency monetary subsidies helped reduce overall poverty from 10.8% in 2020 to 6.5% in 2022, these measures were insufficient to address deep-rooted structural inequalities. Our findings underscore the urgent need for targeted, long-term policies that go beyond temporary financial assistance and tackle systemic disparities linked to rurality, ethnicity, education, and immigration. Such measures are essential for achieving sustainable poverty reduction and fostering inclusive economic growth in Chile.
An innovative methodology in analyzing certain pendulum oscillators
Abstract Pendulum oscillators study harmonic motion, energy conservation, and nonlinear dynamics, providing insights into mechanical vibrations, wave phenomena, weather patterns, and quantum mechanics, with real-world applications in engineering, seismology, and clock mechanisms. The present study addresses three distinct issues related to SPs; a charged magnetic spherical simple pendulum (SP), and a SP composed of heavy cylinders that roll freely in a horizontal plane, and a nonlinear model depicting the motion of a damped SP in a fluid flow. The SPs are analyzed via an innovative technology known as the non-perturbative approach (NPA), which is based on He’s frequency formula (HFF). This advanced approach linearizes a nonlinear ordinary differential equation (ODE), enabling more straightforward analysis and solution. As-well known, implementing the NPA has several advantages, chief among them the removal of the constraints associated with managing Taylor expansions. Consequently, there have been no augmentations to the current restorative forces. Secondly, the novel method enables us to assess the stability criteria of the system away from the traditional perturbation techniques. The numerical comparison of nonlinear ODEs into linear ones using Mathematica Software (MS) is conducted to validate this innovative method. An analysis of the two responses demonstrates a strong concordance, underscoring the necessity of precision of the methodology. Furthermore, to demonstrate the influence of the components on motion behavior, the time history of the calculated solution and the corresponding phase plane plots are accumulated. The use of multiple phase portraits aims to explore stability and instability near equilibrium points by examining the interaction between expanded and cyclotron frequencies, modulated by the magnetic field, for varying azimuthal angular velocities.
Nonmonotonic concentration dependence of the self-diffusion coefficient of surfactants in wormlike micellar solutions
We investigate the concentration dependence of surfactant diffusion in wormlike micellar solutions using dissipative particle dynamics simulations. The simulations show that the self-diffusion coefficient of surfactants exhibits a nonmonotonic dependence on the surfactant concentration, as observed in previous experiments. We quantitatively reveal that this nonmonotonic behavior results from the competition between micellar center-of-mass diffusion and surfactant diffusion within micelles by decomposing the mean-square displacement of surfactants into the corresponding contributions. Furthermore, our detailed analyses demonstrate how the competition between the two diffusion mechanisms is governed by the aggregation number distribution, the dynamics of individual surfactants and micelles, and the kinetics of micellar scission and recombination.