Changes In Relative Intensities Research Articles

Digital traces of offline mobilization.

Since 2009, there has been an increase in global protests and related online activity. Yet, it is unclear how and why online activity is related to the mobilization of offline collective action. One proposition is that online polarization (or a relative change in intensity of posting mobilizing content around a salient grievance) can mobilize people offline. The identity-norm nexus and normative alignment models of collective action further argue that to be mobilizing, these posts need to be socially validated. To test these propositions, across two analyses, we used digital traces of online behavior and data science techniques to model people's online and offline behavior around a mass protest. In Study 1a, we used Twitter behavior posted on the day of the protest by attendees or nonattendees (759 users; 7,592 tweets) to train and test a classifier that predicted, with 80% accuracy, who participated in offline collective action. Attendees used their mobile devices to plan logistics and broadcast their presence at the protest. In Study 1b, using the longitudinal Twitter data and metadata of a subset of users from Study 1a (209 users; 277,556 tweets), we found that participation in the protest was not associated with an individual's online polarization over the year prior to the protest, but it was positively associated with the validation ("likes") they received on their relevant posts. These two studies demonstrate that rather than being low cost or trivial, socially validated online interactions about a grievance are actually key to the mobilization and enactment of collective action. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Toward Understanding Interfacial Phenomena of Anion Exchange Membrane Water Electrolyzers: Investigating the Role of Electrolyte pH Gradient with Operando Raman Spectroscopy

There is growing industrial appeal of anion exchange membrane water electrolyzers (AEMWEs) to produce hydrogen. A significant challenge remains that AEMWE durability testing is not standardized, and more minute interfacial degradation mechanisms between ionomer, catalyst, membrane, and electrolyte are not well characterized. Of particular interest is the impact of electrolyte selection on the polarization performance. There is a general desire to achieve reliable operation with environmentally obtained saltwater as the electrolyte, although this presents numerous challenges manifesting in typically poor long-term durability. Saltwater presents complexities in determining electrolyzer component interfacial phenomena.Performance of AEMWEs is typically benchmarked with hydroxide or carbonate solutions, therefore providing more direct opportunities to study fundamental mechanisms with regards to interactions between surfaces. Of particular interest is the presence of electrolyte anion concentration gradients that depend on the polarization state of the oxygen evolution reaction electrode (OER). We demonstrated in our early work with operando Raman probing of a custom designed spectroelectrochemical cell that there is initial evidence of spatially resolved anion gradients from the OER electrode surface into bulk electrolyte in a half cell configuration. We hypothesize that local pH changes near an electrode surface may impact the polarization via transport limited ion exchange and the relative overpotential of the overall cell, ultimately leading to an iterative and long-term contribution to decaying cell durability.We continue our work with a series of in-situ Raman experiments with a full cell configuration: OER electrode with PGM free catalyst, hydrogen evolution reaction (HER) electrode with PGM free catalyst, and anion conductive polymer membrane. Both electrodes also contain an ionically conductive polymer, or ionomer, that serves as a binder. By increasing the complexity of the system to match that of an industrially relevant configuration, we aim to probe the spatially resolved pH gradient with both potassium hydroxide and potassium carbonate solutions of varying concentrations. We utilized a custom, 3D printed, flow cell design comprising a sapphire observation window and isolated electrolyte flow chambers.Operando Raman spectroscopy measurements were conducted primarily with potassium carbonate solutions by tracking the spatially resolved changes in relative peak intensity of carbonate and bicarbonate signatures. With regards to the carbonate-bicarbonate equilibrium, we calculate changes in pH as the probe approaches the surface of an electrode. We finally connect our findings to a proposed mechanism for the interfacial phenomena relative to cell durability as a function of concentration changes and operating voltages.

Biomimetic affinity sensor for the ultrasensitive detection of neonicotinoids

Multiple pesticides are often used in combination to protect crops from pests. This makes rapid on-site detection of pesticide contamination challenging. Herein, we describe a method for simultaneous detection of diverse neonicotinoid pesticides using a sensor that combines neonicotinoid-specific odorant-binding protein 2 (OBP2), which was cloned from an insect chemical sensing protein and modified gold nanoparticles with local surface plasmon resonance (LSPR)-based digital nanoplasmonometry (DiNM). When neonicotinoid pesticides bind to OBP2 on gold nanoparticles, the induced LSPR shift peak wavelength is too small to be measured using conventional LSPR immunoassays. DiNM records and compares the scattered image intensity in two adjacent wavelength bands, A and B, centered on the LSPR peak. It considers both the peak shift and the relative intensity change in these two bands, resulting in a significant LSPR signal enhancement. Then the spectral-image contrast was computed as the signal response. Using this approach, we obtained excellent limits of detection (LODs) of 1.4, 1.5, and 4.5 ppb for the neonicotinoids imidacloprid, acetamiprid, and dinotefuran, respectively. Blind tests demonstrated high positive and negative rates for teas, approximately 85 and 100%, respectively. Recombinant OBP2 produced in E. coli offers several advantages over antibodies, including high yield, time savings, and cost effectiveness. Moreover, this method is highly selective and sensitive to neonicotinoids, making it practical for field use.

Revealing intermolecular coupling effects on vibrational spectra with infrared-reflectance absorbance analysis of perylene diimide thin films

Intermolecular interactions govern the optical and electronic properties of organic semiconductor thin films. Optimizing the function of molecular devices such as organic solar cells and light emitting diodes relies on understanding structural effects in a heterogeneous film environment. Because organic thin films are typically more disordered than inorganic crystalline semiconductors, advanced techniques are often needed to sufficiently characterize these materials. However, polarized infrared reflectance measurements are a benchtop method that can provide well-resolved vibrational spectra with specificity in their molecular orientation. By using infrared reflectance-absorbance spectroscopy (IRRAS) we relate the effects of intermolecular packing geometry on thin film vibrational spectra of perylene diimide (PDI), a prototypical molecular semiconductor. We analyze a suite of PDIs with differing sidechain substitutions, which adopt distinct crystal packing arrangements in thin films, by comparison of the reflectance spectra to isotropic KBr mixtures. We observe differences in the degree of Davydov splitting as a function of displacement along the short and long molecular axes and the π-π stacking distance that are evident in either the symmetric or anti-symmetric CO stretching frequencies of the solid. The four PDIs also display changes in relative intensity between the two modes that indicate different average molecular orientations.

Study on the Microstructure of a Photonic Crystal Fiber using the Elasto-Optical Effect

Photonic crystal fibers are characterized by their periodic structure with dimensions in the nanometer to micrometer range, which gives them the potential to be applied in various technical areas. In this work, we study the microstructure of a hexagonal photonic crystal fiber through a macroscopic localized compression test and measurements of relative intensity changes of a transmitted signal in the photonic crystal fiber. Our experimental study was carried out by controlling the orientation of the localized compression respective to the cross-section microstructure of the photonic crystal fiber. To complete the study, we developed a theoretical model based on the elasto-optic effect, and the numerical solution obtained with the model was compared with the experimental results. With both experimental and theoretical results, we obtained a causal correlation between the loss of relative intensity of the signal traveling through the hexagonal photonic crystal fiber and the orientation (respective to the fiber plane) of a localized compression on photonic crystal fiber. In this way, we can explore the cross-section microstructure of a photonic crystal fiber and its orientation in a device with a macroscopic compression test.

An Evaluation of Change in the Physical Output in Female Youth Football Players During a Game

This study evaluated the time-to-time aerobic and anaerobic exercise intensities, calculated using the Global Positioning System (GPS), using laboratory measurements of individual physical fitness throughout the game in each female youth football player. In addition, we examine if the anaerobic exercise index calculated by only GPS data presents this evaluation to examine its validity. In the laboratory, the oxygen uptake (V̇O2) matched with moving speed was identified during an incremental exercise test on the treadmill, and the ventilatory (anaerobic) threshold was also analysed to identify individual aerobic and anaerobic exercise intensities. Using these laboratory data, time-to-time changes in individual relative running intensity (aerobic and anaerobic) were visualised from individual GPS data during a football game, and an individual’s sprint output (ability) during the game was evaluated. An index of running intensity and the percentage of anaerobic exercise over the game provided by the GPS software (equivalent distance index [%EDI] and anaerobic index [AI]) did not present the actual individual exercise intensity (ICC(2,1), absolute agreement=−0.031; P=0.596) and percentage of anaerobic exercise (ICC(2,1), absolute agreement=−0.003; P=0.698) values during the game, respectively. These findings suggest that only GPS measurement cannot present the individual actual exercise intensity during a football game because of different individual fitness levels to the same running speed.

Plasmonic biosensor with annular aperture array integrated on a resonant cavity LED

In this paper, we propose an intensity-sensitive compact plasmonic sensor by integrating an annular aperture array with a resonant cavity LED (RCLED). The extraordinary optical transmission (EOT) peak originates from the mutual coupling between surface plasmon polariton (SPP) and Localized surface plasmon resonance (LSPR), which utilizes the EOT peak with narrower linewidth for intensity modulation. Simulation results show that by optimizing the resonant wavelength of the annular aperture array to match the emission wavelength of the RCLEDs, the relative intensity change reaches 97%, and the intensity sensitivity is 9744 %/RIU as a protein molecular layer covered on the sensor.

The possibility of visualizing TGF-β1 expression in ApoE-/- mice atherosclerosis using MR targeted imaging.

Endothelial TGF-β1 signaling is a primary driver of atherosclerosis-associated vascular inflammation. Targeted imaging and inhibition of the expression of TGF-β1 may reduce the atherosclerotic vessel wall inflammation and stop the progression of atherosclerotic plaque. To investigate the possibility of the anti-TGF-β1-ultrasmall superparamagnetic iron oxide (USPIO) specific probe as an imaging marker for the expression of TGF-β1 in ApoE-/- mice atherosclerosis detected with 7.0-T magnetic resonance imaging (MRI). Here, 70 ApoE-/- mice on a high-fat diet served as the experimental group and 30 C57BL/6 mice on a normal diet served as the control group. The morphology of plaques was viewed by H&E staining, and the expression and distribution of TNC and TGF-β1 were detected by immunohistochemical staining. Another 40 mice in the experimental group were classified into a targeted group, which was administrated an anti-TGF-β1-USPIO probe, and the pure group, which was injected with pure USPIO. The 7.0-T MRI showed that the relative signal intensity (rSI) changes of the targeted group decreased more than those of the pure group (-19.34 ± 0.68% vs. -5.61 ± 0.57%; P < 0.05). Histopathological analyses demonstrated expression of TGF-β1 in atherosclerotic plaque formation progression from 10 to 28 weeks. The MR images of the expression of TGF-β1 in atherosclerosis correlated well with the pathological progression of atherosclerotic plaque formation. Anti-TGF-β1-USPIO could provide a useful molecular imaging tool for detecting and monitoring the expression of TGF-β1 in atherosclerotic plaques by MRI.

Computational analysis of the vibrational spectra and structure of aqueous cytosine.

The recently developed efficient protocol for the explicit quantum mechanical modeling of the structure and IR spectra of liquids and solutions [Katsyuba et al., J. Phys. Chem. B, 2020, 124, 6664-6670] is used to describe aqueous solutions of cytosine. The same cluster model of a solute surrounded by the first solvation shell of solvent molecules was shown to be sufficient to reproduce experimental vibrational frequencies and relative IR and Raman intensities. An equally good quality of Raman spectra was provided by B3LYP-D3/def2-TZVP and B3LYP-D3/aug-cc-pVDZ simulations. Computations using the PBE functional were sufficient for modeling of the IR spectra but failed in the simulations of Raman scattering. It is shown that strong changes of frequencies and relative intensities of Raman and IR bands of cytosine, caused by its hydration, cannot be completely assigned to the influence of hydrogen bonds (HBs) with 7 or 8 closest water molecules. They are rather ascribed to the combined effect of solute-solute and solute-solvent HBs with the participation of at least 30 water molecules separating cytosine from the bulk solvent. This suggests that the vibrational modes and derivatives of the polarizability and dipole moment of the solute are mainly locally influenced by its first hydration shell, while the influence of bulk water is rather modest.

Energy storage and photoluminescence properties of Sm&lt;sup&gt;3+&lt;/sup&gt;-doped 0.94Bi&lt;sub&gt;0.5&lt;/sub&gt;Na&lt;sub&gt;0.5&lt;/sub&gt;TiO&lt;sub&gt;3&lt;/sub&gt;-0.06BaTiO&lt;sub&gt;3&lt;/sub&gt; multifunctional ceramics

In recent years, inorganic multifunctional ferroelectric ceramics have been widely utilized in various fields, including aerospace, optical communication, and capacitors, owing to their high stability, easy synthesis, and flexibility. Rare-earth doped ferroelectric materials hold immense potential as a new type of inorganic multifunctional material. This work focuses on the synthesis of &lt;i&gt;x&lt;/i&gt;%Sm&lt;sup&gt;3+&lt;/sup&gt;-doped 0.94Bi&lt;sub&gt;0.5&lt;/sub&gt;Na&lt;sub&gt;0.5&lt;/sub&gt;TiO&lt;sub&gt;3&lt;/sub&gt;-0.06BaTiO&lt;sub&gt;3&lt;/sub&gt; (BNTBT:&lt;i&gt;x&lt;/i&gt;%Sm&lt;sup&gt;3+&lt;/sup&gt; in short) ceramics by using the conventional solid-state sintering method, aiming to comprehensively investigate their ferroelectric, energy storage, and photoluminescence (PL) properties. The X-ray diffraction analysis reveals that the introduction of Sm&lt;sup&gt;3+&lt;/sup&gt; does not trigger off the appearing of secondary phases or changing of the original perovskite structure. The scanning electron microscope (SEM) images demonstrate that Sm&lt;sup&gt;3+&lt;/sup&gt; incorporation effectively restrains the grain growth in BNTBT, resulting in the average grain size decreasing from 1.16 to 0.95 μm. The reduction in remanent polarization (&lt;i&gt;P&lt;/i&gt;&lt;sub&gt;r&lt;/sub&gt;) and coercive field (&lt;i&gt;E&lt;/i&gt;&lt;sub&gt;c&lt;/sub&gt;) can be attributed to both the grain size refinement and the formation of morphotropic phase boundaries (MPBs). Under an applied field of 60 kV/cm, the maximum value of energy storage density (&lt;i&gt;W&lt;/i&gt;&lt;sub&gt;rec&lt;/sub&gt;) reaches to 0.27 J/cm&lt;sup&gt;3&lt;/sup&gt; at an Sm&lt;sup&gt;3+&lt;/sup&gt; doping concentration of 0.6%. The energy storage efficiency (&lt;i&gt;η&lt;/i&gt;) gradually declines with electric field increasing and stabilizes at approximately 45% for Sm&lt;sup&gt;3+&lt;/sup&gt; doping concentrations exceeding 0.6%. This result can be ascribed to the decrease in Δ&lt;i&gt;P&lt;/i&gt; (&lt;i&gt;P&lt;/i&gt;&lt;sub&gt;max&lt;/sub&gt;&lt;sub&gt; &lt;/sub&gt;– &lt;i&gt;P&lt;/i&gt;&lt;sub&gt;r&lt;/sub&gt;) due to the growth of ferroelectric domains as the electric field increases. Additionally, all Sm&lt;sup&gt;3+&lt;/sup&gt;-doped BNTBT ceramics exhibit outstanding PL performance upon being excited with near-ultraviolet (NUV) light at 408 nm, without peak position shifting. The PL intensity peaks when the Sm&lt;sup&gt;3+&lt;/sup&gt; doping concentration is 1.0%, with a relative change (Δ&lt;i&gt;I/I&lt;/i&gt;) reaching to 700% at 701 nm (&lt;sup&gt;4&lt;/sup&gt;G&lt;sub&gt;5/2&lt;/sub&gt;→&lt;sup&gt;6&lt;/sup&gt;H&lt;sub&gt;11/2&lt;/sub&gt;). However, the relative change in PL intensity is minimum at 562 nm (&lt;sup&gt;4&lt;/sup&gt;G&lt;sub&gt;5/2&lt;/sub&gt;→&lt;sup&gt;6&lt;/sup&gt;H&lt;sub&gt;5/2&lt;/sub&gt;) due to the fact that the &lt;sup&gt;4&lt;/sup&gt;G&lt;sub&gt;5/2&lt;/sub&gt;→&lt;sup&gt;6&lt;/sup&gt;H&lt;sub&gt;5/2&lt;/sub&gt; transition represents a magnetic dipole transition, and the PL intensity remains relatively stable despite variations in the crystal field environment surrounding Sm&lt;sup&gt;3+&lt;/sup&gt;. Our successful synthesis of this novel ceramic material, endowed with both energy storage and PL properties, offers a promising avenue for developing inorganic multifunctional materials. The Sm&lt;sup&gt;3+&lt;/sup&gt;-doped BNTBT ceramics hold considerable potential applications in optical memory and multifunctional capacitors.

Multiple parameter analysis for assessing and forecasting earthquake hazards in the Lake Van region, Turkey

A detailed spatial-temporal analysis of the seismic activity in and around the Lake Van region was performed using several seismotectonic parameters such as b-value, Z-value, relative intensity (RI), pattern informatics (PI), and Coulomb stress changes. Correlations between these parameters were analyzed to estimate and forecast potential seismic hazards in the Lake Van region. Particular attention was paid to the parts of the study region that exhibited smaller b-values, higher Z-values, and high-stress changes at the beginning of 2022 and to the locations of earthquake hotspots determined from the composite earthquake forecast map for 2022–2032, i.e., Muradiye, Çaldıran, Özalp, Erçek, Van city center and Gevaş covering the faults of Çaldıran, Yeniköşk, Erciş, Malazgirt and the fault zones of Saray and Van. To provide more accurate interpretations regarding potential earthquake occurrences in the near future, the seismotectonic parameters analyzed in the scope of this study were compared with the corresponding seismological, geological, geodetical, and geochemical variables reported in the literature. This comparison showed that, firstly, our results are consistent with those reported in previous studies, and, secondly, all these variables should be interpreted in combination to correctly assess strong earthquake hazards. Furthermore, this type of multiple-parameter analysis may be important for the description of seismic, tectonic, and structural characteristics of the nature of the crust. Our findings show that almost all seismotectonic parameters indicative of anomaly regions, i.e., lower b-values, higher Z-values, high-stress distribution, and hotspots, were recorded in the same parts of the study region. Thus, the anomaly regions detected at the beginning of 2019 and between 2022 and 2032 may be considered to be potential zones of future great earthquakes. To summarize, the correlations among these variables may provide accurate information for assessing and forecasting earthquake hazards in this region.

Sustainable Sheep Wool/Soy Protein Biocomposites for Sound Absorption

The wool fibers of the Latxa sheep breed were combined with a soy protein isolate (SPI) matrix to develop sustainable biocomposites with acoustic properties, adding value to Latxa sheep wool, which is currently considered a residue. Samples with 7, 10, 15, and 20 wt % wool were prepared by freeze drying in order to develop porous structures, as shown by SEM analysis. Additionally, XRD analysis provided the evidence of a change toward a more amorphous structure with the incorporation of wool fibers due to the interactions between the soy protein and keratin present in wool fibers, as shown by the relative intensity changes in the FTIR bands. The biocomposites were analyzed in a Kundt's tube to obtain their sound absorption coefficient at normal incidence. The results showed an acoustic absorption coefficient that well-surpassed 0.9 for frequencies above 1000 Hz. This performance is comparable to that of the conventional synthetic materials present in the market and, thus, sheep wool/SPI biocomposites are suitable to be used as acoustic absorbers in the building industry, highlighting the potential of replacing not only synthetic fibers but also synthetic polymers, with natural materials to enhance the sustainability of the building sector.

Predictive Factors of Febrile Neutropenia After Primary Prophylactic Pegfilgrastim With DCF Chemotherapy for Esophageal Cancer.

We investigated the predictive factors of febrile neutropenia (FN) after the administration of pegfilgrastim as primary prophylaxis in patients with esophageal cancer who received neoadjuvant chemotherapy with docetaxel, cisplatin, and 5-fluorouracil (DCF) to support the appropriate management of FN. We evaluated changes in neutrophil counts and relative dose intensity (RDI) after the incidence of FN. This retrospective study involved 122 patients with esophageal cancer who were treated with DCF and pegfilgrastim at Showa University Hospital, Japan, between April 2016 and August 2021. The primary outcome was FN incidence after cycle 1 of DCF chemotherapy. The significant independent factors associated with FN incidence were selected using the multivariate analysis. Changes in neutrophil counts and RDI were compared between the FN and non-FN groups. One-hundred patients were included in the analysis. The incidence of FN in cycle 1 was 21%. In the multivariate analysis, geriatric nutritional risk index (GNRI) <92 [odds ratio (OR)=13.162, p<0.001] and combination of platelet and neutrophil-to-lymphocyte ratio (COP-NLR) score of 0 (OR=4.619, p=0.012) were independent predictors of FN. The neutrophil count on day 7-10 and RDI in the FN group were lower than those in the non-FN group (all p<0.05). GNRI <92 and COP-NLR score of 0 are important indicators to predict patients at high risk of DCF chemotherapy-induced FN. Furthermore, FN incidence after pegfilgrastim administration had a strong effect on delayed neutrophil recovery and reduced RDI.

A fluorescent and colorimetric probe for MoO42- based on sulfur quantum dots nanozyme

In this study, with the assistance of chitosan oligosaccharide, sulfur quantum dot (COS-S QDs) nanozyme were synthesized with excellent fluorescence and peroxidase activity. Since MoO42- can statically quench the fluorescence of COS-S QDs and inhibit the peroxidase activity of COS-S QDs, the fluorescence intensity at 435 nm and the absorbance value of TMB at 652 nm were both related to the concentration of MoO42-. The changes of relative fluorescence intensity and absorbance showed a good linear relationship with the concentration of MoO42-, and the detection limits were respectively 0.068 mM and 0.0052 mM. In addition, satisfactory results were also obtained by the use of this new method for the determination of MoO42- in toiletries and cigarettes, with the recovery range of 96∼105.5%.

Contactless skin perfusion monitoring with video cameras: tracking pharmacological vasoconstriction and vasodilation using photoplethysmographic changes

Objectives. Clinical assessment of skin perfusion informs prognosis in critically ill patients. Video camera monitoring could provide an objective, continuous method to monitor skin perfusion. In this prospective, interventional study of healthy volunteers, we tested whether video camera-derived photoplethysmography imaging and colour measurements could detect drug-induced skin perfusion changes. Approach. We monitored the lower limbs of 30 volunteers using video cameras while administering phenylephrine (a vasoconstrictor) and glyceryl trinitrate (a vasodilator). We report relative pixel intensity changes from baseline, as absolute values are sensitive to environmental factors. The primary outcome was the pre- to peak- infusion green channel amplitude change in the pulsatile PPGi waveform component. Secondary outcomes were pre-to-peak changes in the photoplethysmographic imaging waveform baseline, skin colour hue and skin colour saturation. Main results. The 30 participants had a median age of 29 years (IQR 25–34), sixteen (53%) were male. A 34.7% (p = 0.0001) mean decrease in the amplitude of the pulsatile photoplethysmographic imaging waveform occurred following phenylephrine infusion. A 30.7% (p = 0.000004) mean increase occurred following glyceryl trinitrate infusion. The photoplethysmographic imaging baseline decreased with phenylephrine by 2.1% (p = 0.000 02) and increased with glyceryl trinitrate by 0.5% (p = 0.026). Skin colour hue changed in opposite direction with phenylephrine (−0.0013, p = 0.0002) and glyceryl trinitrate (+0.0006, p = 0.019). Skin colour saturation decreased with phenylephrine by 0.0022 (p = 0.0002), with no significant change observed with glyceryl trinitrate (+0.0005, p = 0.21). Significance. Drug-induced vasoconstriction and vasodilation are associated with detectable changes in photoplethysmographic imaging waveform parameters and skin hue. Our findings suggest video cameras have great potential for continuous, contactless skin perfusion monitoring.

Spectral Features of Forbush Decreases during Geomagnetic Storms

Geomagnetic storms and Forbush decreases (FD) on Earth are primarily caused by interplanetary coronal mass ejections (ICMEs) and stream/corotating interaction regions (SIRs/CIRs) originating in the Sun, which are propagated as a low-energy plasma disturbance through the interplanetary magnetic field (IMF). In this paper, we study the variations of the solar-wind parameters (solar wind velocity, plasma density, and IMF-Bz component) and the Earth's disturbance storm-time index (Dst) in relation to cosmic ray flux measurements from 8 neutron monitor stations distributed over Canada, Russia, Finland, and Greenland, during 3 intense geomagnetic storms occurred during the 24th solar cycle (March 16–18, 2015, June 21–23, 2015, and September 7–9, 2017). The wavelet analysis of the cosmic ray intensity reveals the clear evolution of the classical two-step FD with a peak period of approximately 2.1 h. The correlation-delay analysis shows a very strong correlation (∼0.9) between the relative count rate changes in cosmic ray intensity and the indices of solar wind speed and Dst. We obtain similar time-delay responses to the solar wind speed for all the cases (∼4 h), but large discrepancies are seen for the Dst index between the storms. We, therefore, recommend not using the Dst index for predicting Forbush decreases. Finally, we employ the resulting delay times to parameterise the Forbush decreases in terms of the solar wind, and we obtain a predictive model with R2 parameter of an approximate value of 0.8. Moreover, we observe a possible dependence on solar wind proton density which modulates the magnitude of Forbush decreases under similar solar wind speed conditions. Our results verify the suitability of using solar wind parameters to predict Forbush decreases in the cosmic ray flux.

The influence of Ce3+ codoping on upconversion in nanocrystalline NaYF4:Yb3+,Tm3+

Usually, to obtain multicolor upconversion in lanthanides, materials with different codopants, different size, chemical composition or compositional architecture are required. However, designing a material whose emission color can be tuned in-situ by an external stimulus, such as temperature, excitation pulse duration or photoexcitation density, is of great interest for many applications, but still remains a challenge. The possible solution for this issue can be achieved by intentional codoping the luminescent materials with optically active ions which can disturb or compete with other energy transfer processes, and in consequence lead to changes in relative emission intensity, thus the dominant emission color. Here we synthesized and investigated colloidal luminescent Yb3+ and Tm3+ doped NaYF4 nanoparticles which were codoped with optically active Ce3+ ions, whose relative emission intensity ratios between 1D2→3F4 (at 450 nm), 1G4→3H6 (at 475 nm), 1G4→3F4 (at 650 nm), and 3H4→3H6 (at 800 nm) were significantly dependent from external stimulus – namely temperature and/or excitation pulse length. Our results shows two fold increase in 450/800, 470/800 and 650/800 luminescence intensity bands ratios (LIR) only after incorporation of Ce3+ ions to the material, and even three-fold increase in those LIR after changing the excitation conditions (i.e. pulse width). Moreover, temperature dependent luminescence properties revealed relative sensitivity of 4%/K for the 450/800 and 470/800 bands ratio and almost 5.5%/K for the 650/800 band ratio close to 0 °C. By switching to physiological range of temperatures, the thermal sensitivity decreased to around 2%/K for the 450/800 and 470/800 bands ratio and to over 2.5%/K for 650/800 bands ratio, which should be considered as significant values and suitable for temperature sensing in practical applications. It is worth noting that the thermal sensitivity values can be further enhanced by applying different excitation pulse width. The proposed materials allows to tune its emissions as well as thermal properties by changing the dopant concentration or more importantly also in situ, through excitation scheme modifications.

Stimulated vacuum emission and photon absorption in strong electromagnetic fields

According to quantum electrodynamics (QED), a strong electromagnetic field can make the vacuum state decay via the production of electron-positron pairs. Here we investigate the emission of soft photons which accompanies a nonperturbative process of pair production. Our analysis is carried out within the Furry picture to first order in the fine-structure constant. Also, it is shown that the presence of photons in the initial state gives rise to an additional (stimulated) channel of photon emission besides the pure vacuum one. On the other hand, the number of final (signal) photons includes also a negative contribution due to photon absorption within the pair production process. These contributions are evaluated and compared. To obtain quantitative predictions in the domain of realistic field parameters, we employ the Wentzel-Kramers-Brillouin approach. We propose using an optical-probe photon beam, whose intensity changes as it traverses a spatial region where a strong electric component of a background laser field is present. It is demonstrated that relative intensity changes on the level of 1% can be experimentally observed once the intensity of the strong background field exceeds ${10}^{27}\text{ }\text{ }{\mathrm{W}/\mathrm{cm}}^{2}$ within a large laser-wavelength interval. This finding is expected to significantly support possible experimental investigations of nonlinear QED phenomena in the nonperturbative regime.

Nonoperative Treatment of Finger Flexor Tenosynovitis in Sport Climbers-A Retrospective Descriptive Study Based on a Clinical 10-Year Database.

Simple SummaryFinger flexor tenosynovitis is among the most frequent overuse injuries in sport climbers. Targeted therapy is currently based mostly on reports of the anecdotal practical experience of single centers rather than scientific investigations, as there is very little research available on this pathology. The aim of this study was to describe the nonoperative treatment outcomes of finger flexor tenosynovitis treatments in sport climbers by retrospectively asking patients about injury triggers, therapy contents and outcomes. All patients were initially treated conservatively, and only one of the patients needed further therapy in the form of a single injection with hyaluronic acid; none of them underwent further operative treatment. The average symptom duration was 30.5 weeks, and all patients were able to resume climbing, with approximately 75% of them regaining or exceeding their initial climbing level. These good to excellent outcomes and no correlation between particular therapy contents and therapy outcome suggest that finger flexor tenosynovitis in sport climbers has a favorable natural course without requiring invasive therapy. However, further cohort studies and, ultimately, randomized controlled trials are needed to conclusively confirm our promising observations from this study.The aim of this study was to describe the nonoperative treatment outcomes of finger flexor tenosynovitis in sport climbers and to evaluate the association with baseline measures and therapy contents. Sixty-five sport climbers (49 males, mean age 34.1 years) diagnosed with tenosynovitis of the finger flexors were retrospectively asked about injury triggers, therapy contents and outcomes. Pulley thickness was measured by ultrasound. All patients were initially treated conservatively, and only one of the patients needed further therapy (single injection with hyaluronic acid); none of them underwent surgical treatment. The most frequently applied therapy was climbing-related load reduction (91%). The treatment resulted in a statistically significant reduction in pain intensity during climbing (before/after therapy ratio [Visual Analog Scale (VAS)/VAS] = 0.62, 95% CI = 0.55, 0.68). The average duration of the symptoms was 30.5 weeks (range 1–120 weeks). In a multiple linear regression analysis, initial daily life pain intensity and a climbing level higher than 7b according to the French/sport grading scale were the only predictive parameters for the relative change in pain intensity and symptom duration, respectively. All patients were able to resume climbing, with 75% regaining or even exceeding their initial climbing level. The good to excellent outcomes and no correlation between particular therapy contents and therapy outcome may suggest that finger flexor tenosynovitis in sport climbers has a favorable natural course without requiring invasive therapy. However, further cohort studies and, ultimately, randomized controlled trials are needed to conclusively confirm our promising observations.

Giant spectral renormalization and complex hybridization physics in the Kondo lattice system CeCuSb2

We investigate the electronic structure of a Kondo lattice system, CeCuSb2 exhibiting significant mass enhancement and Kondo-type behavior. We observe multiple features in the hard x-ray photoemission spectra of Ce core levels due to strong final-state effects. The depth-resolved data exhibit a significant change in relative intensity of the features with the surface sensitivity of the probe. The extracted surface and bulk spectral functions are different and exhibit a Kondo-like feature at higher binding energies in addition to the well and poorly screened features. The core-level spectra of Sb exhibit huge and complex changes as a function of the surface sensitivity of the technique. The analysis of the experimental data suggests that the two non-equivalent Sb sites possess different electronic structures and in each category, the Sb layers close to the surface are different from the bulk ones. An increase in temperature influences the Ce-Sb hybridization significantly. The plasmon-excitation-induced loss features are also observed in all core level spectra. All these results reveal the importance of Ce-Sb hybridizations and indicate that the complex renormalization of Ce-Sb hybridization may be the reason for the exotic electronic properties of this system.