Browse Articles

Spearfishing and public health promotion: A cross-sectional analysis of the Hawaiʻi Behavioral Risk Factor Surveillance System Survey

Spearfishing, a culturally relevant practice in many locations globally, may foster physical activity and enhance well-being by promoting social cohesion, food security, and nature connectedness, but is understudied in public health promotion and surveillance. This study measured the population-level prevalence of lifetime spearfishing engagement in Hawaiʻi and identified associated factors for public health promotion. The Hawaiian Islands present an ideal setting for such activities due to its central Pacific location and a diverse population with cultural ties to spearfishing. In 2019 and 2020, lifetime spearfishing engagement was added to the Hawai’i Behavioral Risk Factor Surveillance System (N = 12,737). Prevalence ratios (PR) and 95% confidence intervals (95%CI) were estimated for spearfishing “sometimes,” “often,” or “very often” during one’s lifetime, considering sociodemographic, health behavior, and health status variables. A quarter of respondents statewide reported engagement, with higher rates amongst men (41%), Native Hawaiians (43%), other Pacific Islanders (36%), American Indian or Alaskan Native (32%), and rural island residents of Lānaʻi (51%) and Molokaʻi (43%). All age groups reported similar lifetime engagement. After statistical adjustment, those with a high school diploma or less were significantly more likely to have engaged in spearfishing than those with higher education. Spearfishing engagement was also associated with a higher likelihood of meeting physical activity guidelines (PR 1.45 95%CI 1.29-1.63). There is widespread lifelong engagement in spearfishing in Hawaiʻi, especially among Indigenous and rural populations. Supporting culturally relevant activities, such as spearfishing, is a strength-based approach to health promotion with global relevance, including encouraging physical activity.

Bulldogs stenosis degree classification using synthetic images created by generative artificial intelligence

Parametric study of “filament and gap” models of resistive switching in TaOx-based devices.

A finite element model consisting of a conducting filament with or without a gap was used to reproduce the behavior of TaOx-based resistive switching devices. The specific goal was to explore the range of possible filament parameters such as filament diameter, composition, gap width, and composition to reproduce the conductance and shape of I–V while keeping the maximum temperature within the acceptable range allowing for ion motion and preventing melting. The model solving heat and charge transport produced a good agreement with experimental data for the oxygen content in the filament below TaO1.3, the filament diameter range between 6 and 22 nm, and the gap oxygen content between TaO1.7 and TaO1.85. Gap width was not limited to either low or high sides according to the criteria considered in this report. The obtained filament composition corresponds to oxygen deficiency an order of magnitude higher than one estimated by other modeling efforts. This was in large part due to the use of recent experimental values of conductivity as a function of composition and temperature. Our modeling results imply that a large fraction of atoms leaves and/or accumulates within the filament to produce a large relative concentration change. This, in turn, necessitates the inclusion of strain energy in the filament formation modeling. In addition, the results reproduce non-linear I–V without the necessity of assuming the Poole–Frenkel type of electrical conduction or the presence of a barrier at the oxide/metal interface.

Local hybrid alternatives to the orbital density approximation reduce the orbital dependence of self-interaction corrected DFT and the overbinding of DFT-corrected correlated wavefunctions

This work presents local hybrid alternatives to the orbital density approximation employed in self-interaction corrected density functional theory (SIC-DFT) and extended for use in DFT-corrected correlated wavefunction approaches (CAS-DFT). When combined with standard approximate density functionals, the orbital density approximation leaves SIC-DFT energies strongly dependent on unitary transforms among occupied orbitals and leaves CAS-DFT energies overbound. The alternatives presented here reduce both errors. The orbital density approximation and the local hybrid alternatives are shown to approximate an underlying nondiagonal exchange–correlation hole. A preliminary extension is presented to active–virtual correlation. These results motivate exploration of local hybrid concepts in SIC-DFT and CAS-DFT.

The role of E-learning in institutions of higher education in achieving the goals of sustainable development in Jordan

E-learning plays an important role in achieving the Sustainable Development Goals (SDGs). This research aimed to E-Learning’s impact on attaining SDGs in Jordanian Higher Education with a primary focus on the University of Jordan as a case study. The study was conducted on a sample of 3,000 students at the University of Jordan from various majors and academic levels and for both genders. The study adopted the quantitative statistical analysis method where a questionnaire was distributed electronically to students through the official platforms approved by the university. The results of the research showed that there is a positive role for E-learning in Higher Education institutions in achieving the sustainable development goals in Jordan, especially SDGs (1, 2, 4, 5, 7, 8, 9, 11, 12, 15, 16 and 17). Through the university’s efforts to develop the skills of students and faculty members in the field of technology and innovation, and holding seminars and conferences via E-learning platforms that enable universities to disseminate valuable information, participate in open dialogues, and raise awareness about SDGs and how to achieve them. Despite these efforts, more remain required to work towards the achievement of SDGs (3, 6, 10, 13, and 14).

RETRACTED ARTICLE: Scattering and stress concentration of SH guided waves by a semicircular hole on the boundary of an infinite piezoelectric ceramic plate

Sound velocities, elasticity, hardness, and fracture toughness of novel <i>hcp</i> and <i>bcc</i> structured Ti-based medium-entropy alloys

Sound velocities, bulk modulus (B), shear rigidity (G), Young's modulus (E), Vickers hardness (HV), and fracture toughness (KIC) of Ti-based medium-entropy alloys (MEAs) of TiZrHf, TiZrNb, and TiHfNb are investigated using ultrasonic interferometry combined with Vickers hardness measurements. It is found that the Vickers hardness of hexagonal TiZrHf MEA is achieved up to ∼6.0 GPa, which is ∼1.3 times higher than the bcc-structured TiZrNb and TiHfNb ones. Meanwhile, the fracture toughness of cubic TiZrNb and TiHfNb MEAs is ranging from 6.0 to 7.8 MPa m1/2, which is about 1.5–2 times stronger than the hcp-TiZrHf counterpart. Additionally, the hcp-TiZrHf MEA exhibits a higher Young's modulus of around 130 GPa, approximately 20 GPa higher that of the bcc-TiZrNb MEA. The underlying mechanism for improving B, G, E, KIC, and/or HV, as well as the composition and structure dependent mechanical properties are clarified by the variations in bond strength, electronic structure, and lattice distortion of Ti-based MEAs. These findings explore how microstructural characteristics affect properties such as the bulk modulus and shear rigidity of M/HEAs and provide new insights into tuning mechanical properties through the modulation of alloy compositions.

Coherent nonlinear optical response for high-intensity excitation

The calculation of the coherent nonlinear response of a system is essential to correctly interpret results from advanced techniques such as two-dimensional coherent spectroscopy. Usually, even for the simplest systems, such calculations are either performed for low-intensity excitations where perturbative methods are valid and/or by assuming a simplified pulse envelope, such as a δ-function in time. Here, we use the phase-cycling method for the exact calculation of the nonlinear response without making the aforementioned approximations even for high-intensity excitation. We compare the simulation results to several experimental observations to prove the validity of these calculations. The saturation of the photon-echo signal from excitons in a semiconductor quantum well sample is measured. The excitation-intensity dependent measurement shows nonlinear contributions up to twelfth order. Intensity-dependent simulations reproduce this effect without explicitly considering higher-order interactions. In addition, we present simulation results that replicate previously reported experiments with high-intensity excitation of semiconductor quantum dots. By accurately reproducing a variety of phenomena such as higher-order contributions, switching of coherent signals, and changes in photon-echo transients, we prove the efficacy of the phase-cycling method to calculate the coherent nonlinear signal for high-intensity excitation. This method would be particularly useful for systems with multiple, well-separated peaks and/or large inhomogeneities.

A study of Mandelbrot and Julia Sets via Picard–Thakur iteration with s-convexity

Nowadays, many researchers are employing various iterative techniques to analyse the dynamics of fractal patterns. In this paper, we explore the formation of Mandelbrot and Julia sets using the Picard–Thakur iteration process, extended with s-convexity. To achieve this, we establish an escape criterion using a complex polynomial of the form xk+1+c, where k ≥ 1 and x, c ∈ ℂ. Based on our proposed algorithms, we provide graphical illustrations of the Mandelbrot and Julia sets. Additionally, we extend our research to examine the relationship between the sizes of Mandelbrot and Julia sets and the iteration parameters, utilising some well-known methods from the literature.

Operando detection of dissolved oxygen in fluid solution using a submersible rapid scan EPR on a chip dipstick sensor

Abstract Electron paramagnetic resonance (EPR) is an accurate and efficient technique to probe unpaired electrons in many applications across materials science, chemistry, and biology. Dynamic processes are investigated using EPR; however, these applications are limited by the use of resonator-based spectrometers such that the entire process must be confined to the resonator. The EPR-on-a-chip (EPRoC) device circumvents this limitation by integrating the entire EPR spectrometer into a single microchip. In this approach, the coil of a voltage-controlled oscillator (VCO) is used as the microwave source and detector simultaneously, operating under a protective coating such that the device may be placed in the sample solution directly. Additionally, improvements in sensitivity via rapid scan EPR (RS-EPR/RS-EPRoC) increase the accessible applications where SNR per measurement time is the fundamental limit. The herein reported device combines a dipstick EPRoC sensor with the enhanced sensitivity of frequency-swept frequency modulated rapid scan to measure triarylmethyl (trityl, Ox071) oxygen-sensitive probes dissolved in aqueous solutions. EPR spectra of Ox071 solutions were recorded using the RS-EPRoC sensor while varying the oxygen concentration of the solution between normal atmosphere and after purging the solution with nitrogen gas. We demonstrate that EPRoC may be employed to monitor dissolved oxygen in fluid solution in an online fashion.

Evidence of the magneto-optical Kerr spectral shifts induced by quasi-static strain

We demonstrate a dynamical wavelength shift in the magneto-optical Kerr spectrum of a Permalloy thin film, excited by femtosecond laser pulses. Through precise measurements of magneto-optical dynamics with narrow-bandwidth probe pulses, we found systematic variations in the differential Kerr rotation and ellipticity, corresponding to the shape of the static Kerr spectrum. We attribute this behavior to a spectral shift caused by quasi-static strain driven by femtosecond laser-induced heating. Supporting this interpretation, we successfully observed a sign reversal in the static Kerr signal during the demagnetization process. By isolating two contributions to the observed dynamics—a reduction in magnetization due to increased spin temperature and an extra gain from the Kerr spectrum shift—we quantified a horizontal shift of the Kerr spectrum toward shorter wavelengths.

Toward a Monte Carlo simulation of protein systems in amino-acid sequence space

In this article, we present our strategy for studying amino-acid sequence dependences on protein structures. For this purpose, performing Metropolis Monte Carlo simulations in the amino-acid sequence space is necessary. We want to use a coarse-grained protein model with an accurate potential energy function. We introduce a method for optimizing potential-energy parameters based on the native protein structure database, Protein Data Bank.

Correction: Coping with COVID-19: Differences in hope, resilience, and mental well-being across U.S. racial groups

Multi-omic analyses reveal aberrant DNA methylation patterns and the associated biomarkers of nasopharyngeal carcinoma and its cancer stem cells

Dual-band selective rainbow trapping in two-dimensional gradient valley phononic crystals

The realization of topological rainbow trapping provides significant potential for applications in energy storage and recovery, signal sensing, and related fields. Most studies focus on the first bandgap of valley phononic crystals, which presents a challenge for developing multi-band topological acoustic devices. This study designs a three-legged circular rod valley phononic crystal, where spatial symmetry is broken through rotation to open two Dirac cones. It observes topological edge states within the ranges of the original two bandgaps by combining two valley phononic crystals with different topological phases. In addition, the magnitude of the group velocity is calculated in the supercells at different rod lengths, revealing points with a group velocity of zero at different frequencies, thus realizing rainbow trapping in dual bandgaps. The findings indicated that within bandgap 1, the acoustic waves can only propagate along the waveguide from left to right. The acoustic waves are sequentially trapped at different locations as the frequency increases. In the range of bandgap 2, the acoustic waves can only propagate along the waveguide from right to left. As the frequency decreases, the acoustic waves are trapped at different locations. The designed three-legged circular rod valley phononic crystal facilitates the unidirectional propagation of acoustic waves at specific frequencies, making it suitable for applications in acoustic diodes. The realization of dual-band topological rainbow trapping provides potential application value for energy recovery, signal sensors, and other technological applications.

Revisiting the question of what instantaneous normal modes tell us about liquid dynamics

The lack of a well-defined equilibrium reference configuration has long hindered a comprehensive atomic-level understanding of liquid dynamics and properties. The Instantaneous Normal Mode (INM) approach, which involves diagonalizing the Hessian matrix of potential energy in instantaneous liquid configurations, has emerged as a promising framework in this direction. However, several conceptual challenges remain, particularly related to the approach’s inability to capture anharmonic effects. In this study, we present a set of “experimental facts” through a comprehensive INM analysis of simulated systems, including Ar, Xe, N2, CS2, Ga, and Pb, across a wide temperature range from the solid to gas phase. First, we examine the INM density of states (DOS) and compare it to the DOS obtained from the velocity auto-correlation function. We then analyze the temperature dependence of the fraction of unstable modes and the low-frequency slope of the INM DOS in search of potential universal behaviors. Furthermore, we explore the relationship between INMs and other properties of liquids, including the liquid-like to gas-like dynamical crossover and the momentum gap of collective shear waves. In addition, we investigate the INM spectrum at low temperatures as the system approaches the solid phase, revealing a significant fraction of unstable modes even in crystalline solids. Finally, we confirm the existence of a recently discussed cusp-like singularity in the INM eigenvalue spectrum and uncover its complex temperature-dependent behavior, challenging current theoretical models.

Selecting species for vineyard inter-row vegetation cover requires consideration of microenvironmental conditions

Vegetation between the vineyard rows is considered a service crop due to the many ecosystem services it provides. These benefits mostly depend on the species or mixtures selected. Vineyard can directly impact the microclimate by modifying the amount of energy available for the herbaceous layer affecting parameters such as soil temperature and moisture. Our hypothesis was that changes in inter-row vegetation composition change are driven by micronvironmental condition. A field trial was conducted in a vineyard of Cabernet Sauvignon Vitis vinifera L. cultivars, managed organically, in north-eastern Italy, where three blends of grass species (Shedonorus arundinaceus, Lolium perenne, and Festuca rubra) and two grass-legume mixtures were grown in the inter-rows. These were compared with spontaneous vegetation and bare soil regularly tilled. Each type of inter-row cover, including resident vegetation, was subjected to mulching and non-mulching treatments. The study aimed at evaluate the response to microenvironmental conditions of seeded species, mixtures, and spontaneous vegetation in the inter-row spaces of the vineyard. The relative abundance of each species was recorded during the spring after seeding (2019) and during the spring of 2020. Soil compaction, soil temperature, and soil moisture were measured during spring 2020. A significant change in botanical composition occurred two years after seeding according to the type of vegetation. However, some species remained in or spread to specific sections of the inter-row. Lolium perenne was more abundant in the southwest and northeast sections of the inter-row, where there was greater soil compaction. Similarly, the abundance of weed species such as Cynodon dactylon, Setaria italica, and Plantago lanceolata, was related to microenvironmental conditions. Seeded (Festuca rubra) or weed species (C. dactylon, Erigeron annuus, and Lactuca serriola) appear to benefit from soil moisture and higher temperatures. Therefore, microenvironment adaptability is the primary factor to consider when selecting species for vineyard inter-row cover.

Variable scale operational path planning for land levelling based on the improved ant colony optimization algorithm

Flatbands of spin waves in two-dimensional magnonic crystals with kagome lattices

The study theoretically investigates the flatbands in two-dimensional magnonic crystals (MCs) with kagome lattices based on the plane-wave expansion method. In such MCs composed of ferromagnetic cylinders embedded in another ferromagnetic matrix, the formation of flatbands is due to spin waves localizing at a certain ferromagnetic material with a small exchange constant. Moreover, the position, number, and flatness of flatbands can be adjusted by changing the filling fractions. The studies on generating and adjusting flatbands in MCs expand the research content of condensed matter physics thin film deposition processes for halide perovskites, University of Helsinki, 2023.

The structure and symmetry of modular state space for complex quantum systems

Understanding the state space structure of complex quantum systems can help to effectively characterize the system properties and explore underlying mechanisms. The structure of the state space could be quite complicated for quantum many-body systems, and the systematic decomposition of the state space is normally involved. Recently, a modular tensor diagram approach was proposed to reorganize the state space hierarchically based on a modular basis. Here, we review the construction of spin eigenfunctions for multiple exciton systems and further develop modular tensor diagrams to exemplify the hierarchical symmetry of the state space. The newly constructed spin eigenfunctions for quadruple excitons, along with the results for triple excitons, are used to demonstrate the effective decomposition of the state space into hierarchical tensorial structures. A universal recursive relation is derived to determine the coefficients of spin eigenfunctions exhibiting transformation symmetry between different classes of elementary modules for an arbitrary number of exciton units. Interestingly, different coupling schemes mapped to quantum many-body interactions lead to different spin adapted basis states, which may correspond to different realistic systems upon the breakdown of spin degeneracy. This work highlights the hierarchical symmetry of the tensorial structure of quantum many-body systems, which may facilitate a better understanding of the structure property relationship toward the object-oriented materials design.