Constant observation

We propose and experimentally demonstrate the generation of enhanced optical springs using the optical Kerr effect. A nonlinear optical crystal is inserted into a Fabry-Perot cavity with a movable mirror, and a chain of second-order nonlinear optical effects in the phase-mismatched condition induces the Kerr effect. The optical spring constant is enhanced by a factor of 1.6±0.1 over linear theory. To our knowledge, this is the first realization of optomechanical coupling enhancement using a nonlinear optical effect, which has been theoretically investigated to overcome the performance limitations of linear optomechanical systems...

Stimuli-responsive polymers are an important class of materials with many applications in nanotechnology and drug delivery. The most prominent one is poly- N -isopropylacrylamide (PNIPAm). The characterization of the kinetics of its change after a temperature jump is still a lively research topic, especially at nanometer-length scales where it is not possible to rely on conventional microscopic techniques. Here, we measured in real time the collapse of a PNIPAm shell on silica nanoparticles with megahertz x-ray photon correlation spectroscopy at the European XFEL...

OBJECTIVES: To investigate the dimensional stability of various 3D-printed models derived from resin and plant-based, biodegradable plastics (PLA) under specific storage conditions for a period of up to 21 weeks. MATERIALS AND METHODS: Four different printing materials, including Draft V2, study model 2, and Ortho model OD01 resins as well as PLA mineral, were evaluated over a 21-week period. Eighty 3D-printed models were divided equally into two groups, with one group stored in darkness and the other exposed to daylight...

Localized excitation in traditional organic photocatalysts typically prevents the generation and extraction of photo-induced free charge carriers, limiting their activity enhancement under illumination. Here, we enhance delocalized photoexcitation of small molecular photovoltaic catalysts by weakening their electron-phonon coupling via rational fluoro-substitution. The optimized 2FBP-4F catalyst we develop here exhibits a minimized Huang-Rhys factor of 0.35 in solution, high dielectric constant and strong crystallization in the solid state...

BACKGROUND: Many data were published about Long-Covid prevalence, very few about the findings of new cardiac alterations (NCA) in COVID-19-recovered people. ARCA-post-COVID is an observational study designed to investigate the prevalence of NCA in patients recovered from Covid-19.Methods: from June 2020 to December 2022, we enrolled 502 patients with a positive nasopharyngeal swab for SARS-CoV2 and a subsequent negative one. We performed anamnesis, lab-test, and routine cardiological tests (ECG, Holter, TTE)...

Isochoric (constant volume) freezing is a novel food preservation technology that has demonstrated the ability to preserve food products at subfreezing temperatures in an unfrozen state, thereby avoiding the detrimental effects of ice formation. It minimizes the quality loss of fresh fruits and juices, increases their nutrient content, and reduces microbial counts. Orange juice (OJ) samples were subjected to conventional freezing (CF) and isochoric freezing (IF) for 7 days and then stored at 4°C for an additional 7 days...

In this study, the characteristics, anaerobic treatability, and energy potential of wastewater samples taken from a dairy products industry were investigated. It was determined that the wastewater has a high organic load (COD = 2800 mg O2 /L) and a large proportion of this load is biodegradable. The biochemical methane potential (BMP) value of wastewater was measured as 1118.71 ± 122 ml CH4 /L. Volatile solids (VS) removal of 67.25 ± 4.98% was achieved during batch tests and the obtained methane yield was calculated as 411...

The use of insecticides presents a risk to the environment because they can accumulate in the water, soil, air, and organisms, endangering human and animal health. It is therefore essential to investigate the effects of different groups of insecticides on individual biomacromolecules such as DNA. We studied fipronil, which belongs to the group of phenylpyrazole insecticides. The interaction of fipronil with calf thymus DNA was investigated using spectroscopic methods (absorption and fluorescence spectroscopy) complemented with infrared spectroscopy and viscosity measurement...

Methylation and hydroxymethylation of cytosine moieties in CpG islands of specific genes are epigenetic processes shown to be involved in the development of cervical (pre)neoplastic lesions. We studied global (hydroxy)methylation during the subsequent steps in the carcinogenic process of the uterine cervix by using immunohistochemical protocols for the detection of 5-methylcytosine (5-mC) and 5-hydroxymethylcytosine (5-hmC) in paraffin-embedded tissues of the normal epithelia and (pre)malignant lesions. This approach allowed obtaining spatially resolved information of (epi)genetic alterations for individual cell populations in morphologically heterogeneous tissue samples...

In multistable dot lattices, the orientation we perceive is attracted toward the orientation we perceived in the immediately preceding stimulus and repelled from the orientation for which most evidence was present previously (Van Geert, Moors, Haaf, & Wagemans, 2022). Theoretically-inspired models have been proposed to explain the co-occurrence of attractive and repulsive context effects in multistable dot lattice tasks, but these models artificially induced an influence of the previous trial on the current one without detailing the process underlying such an influence (Gepshtein & Kubovy, 2005; Schwiedrzik et al...

Kinetic and nonkinetic contributions to the Tafel slope value can be separated using a Tafel slope plot, where a constant Tafel slope region indicates kinetic meaningfulness. Here, we compare the Tafel slope values obtained from linear sweep voltammetry to the values obtained from chronoamperometry and impedance spectroscopy, and we apply the Tafel slope plot to various electrocatalytic reactions. We show that similar Tafel slope values are observed from the different techniques under high-mass-transport conditions for the oxygen evolution reaction on NiFeOOH in 0...

In response to environmental concerns, researchers explore fly ash as a cement replacement material, and crushed bricks as a cost-effective and load-reducing aggregate, particularly where stone chips are scarce. Therefore, this study investigates the mechanical properties and microstructure of brick aggregate concrete (BAC) with raw fly ash (FA) as a partial replacement of cement. The research involved casting raw FA based BAC (FBAC) cylinders (100 mm diameter and 200 mm height) and prism (100 × 100 × 500 mm) with varying levels of FA (0-25%) using a constant mix proportion by volume of 1:1...

Macroscopic dipole moments formed in electrolytic cells influence dielectric properties of the cells, and their magnitudes can be quantified by dielectric spectroscopy. We analyze the dielectric spectra observed for dilute electrolytic cells in low-frequency regions from two perspectives: space-charge polarization and diffuse double layers on the electrodes. The difference between the two polarization phenomena is characterized by the effective dielectric constant and the kinetic parameter introduced in the Poisson-Nernst-Planck model...

In this paper, the underlying problem with the color-gradient (CG) method in handling density-contrast fluids is explored. It is shown that the CG method is not fluid invariant. Based on nondimensionalizing the CG method, a phase-field interface-capturing model is proposed which tackles the difficulty of handling density-contrast fluids. The proposed formulation is developed for incompressible, immiscible two-fluid flows without phase-change phenomena, and a solver based on the lattice Boltzmann method is proposed...

We study a one dimensional gas of N noninteracting diffusing particles in a harmonic trap, whose stiffness switches between two values μ_{1} and μ_{2} with constant rates r_{1} and r_{2}, respectively. Despite the absence of direct interaction between the particles, we show that strong correlations between them emerge in the stationary state at long times, induced purely by the dynamics itself. We compute exactly the joint distribution of the positions of the particles in the stationary state, which allows us to compute several physical observables analytically...

The influence of oat lipids on the structural, thermal, rheological, and in vitro digestibility properties of oat starch under heat processing conditions was investigated. X-ray diffraction, fourier infrared spectroscopy, and differential scanning calorimetry revealed the formation of a V-shaped crystal structure between starch and lipid, resulting in enhanced orderliness and enthalpy. Oat lipids decreased the final viscosity and gel strength of oat starch while weakening the trend towards gel network formation...

Herein, efficient degradation of hexabromocyclododecane (HBCD) and Lindane, a persistent organic pollutant using guar gum based calcium oxide doped silicon dioxide (GG-CaO@SiO2 ) has been reported. The nanocomposite was prepared by waste egg shell (CaO) and rice husk (SiO2 ) was well characterized. The maximum degradation of HBCD and Lindane were observed at 8 mg catalyst loading, basic pH, and 2 mg L-1 of pollutant amount. The photocatalytic performance of GG-CaO@SiO2 for HBCD and Lindane photodegradation was evaluated, and it was found that the rate constant increased in the order of GG-CaO@SiO2  > CaO@SiO2  > GG...

INTRODUCTION: Glucagon receptor agonism is currently explored for the treatment of obesity and metabolic dysfunction-associated steatotic liver disease (MASLD). The metabolic effects of glucagon receptor agonism may in part be mediated by increases in circulating levels of Fibroblast Growth Factor 21 (FGF21) and Growth Differentiation Factor 15 (GDF15). The effect of glucagon agonism on FGF21 and GDF15 levels remains uncertain, especially in the context of elevated insulin levels commonly observed in metabolic diseases...

The rotational spectra of two valine methyl ester (ValOMe) conformers have been measured using a cavity-based Fourier-transform microwave spectrometer in the range of 9-18 GHz. Ten conformers of ValOMe were modeled using the ωB97XD/6-311++G(d,p) level of theory, and separate spectra arising from two lowest-energy conformations were observed and assigned. 44 rotational transitions were assigned to conformer I, the lowest-energy configuration, and were fit to Watson's A -reduced Hamiltonian: A = 2552.0145(5) MHz, B = 1041...

Teeth exemplify architectures comprising an interplay of inorganic and organic constituents, resulting in sophisticated natural composites. Rodents (Rodentia) showcase extraordinary adaptations, with their continuously growing incisors surpassing human teeth in functional and structural optimizations. In this study, employing state-of-the-art direct atomic-scale imaging and nanoscale spectroscopies, we present compelling evidence that the release of material from ameloblasts and the subsequent formation of iron-rich enamel and surface layers in the constantly growing incisors of rodents are complex orchestrated processes, intricately regulated and independent of environmental factors...