Magnitude Of Shift Research Articles

Evaluation and comparison of synthetic computed tomography algorithms with 3T MRI for prostate radiotherapy: AI-based versus bulk density method.

Synthetic computed tomography (sCT)-algorithms, which generate computed tomography images from magnetic resonance imaging data, are becoming part of the clinical radiotherapy workflow. The aim of this retrospective study was to evaluate and compare commercial bulk-density-method (BM)-based and AI (artificial intelligence)-based-algorithms using 3T magnetic resonance imaging (MRI) with patient data as part of the local clinical commissioning process. 44 prostate radiotherapy patients were subjected to MRI and treatment planning CT (TPCT) scans. From the MRI images, sCT images with two different sCT algorithms were generated. The sCT images were evaluated by visual inspection of artifacts. Both sCT methods were compared to TPCT, with Dice similarity score(DSC) of bone and body contours, DVH parameters for CTV, bladder and rectum, and gamma-analysis. Accuracy for treatment alignment using sCT images was also tested. Various limits were used to define whether the differences between sCT methods to TPCT were clinically relevant (DVH parameters<2%, gamma-analysis passing rates 90%, 95%, and 98%, and the DSC 0.98 for body and 0.7 for bone). Our results show that, differences in CTV-dose coverage values were<2% in most of the patients with both sCT algorithms when compared to reference dose coverage. While AI-sCT had mean dose coverage difference<0,5% and BM-sCT<1%. Gamma-analysis showed that the AI-sCT mean passing rates were 95.4%, 98.6%, and 99.4% with 1mm1%, 2mm2%, and 3mm3% criteria, respectively. Similarly for BM-sCT the mean passing rates were 93.4%, 98.2%, and 99.2%. For the treatment alignment accuracy, the mean difference in magnitude of the translational shifts was 1.43mm for BM-sCT and 1.57mm for AI-sCT. Even though AI-sCT showed statistically better correspondence to TPCT, the differences were not clinically relevant with any of the limits. Visual evaluation showed artifacts in the AI-sCT especially in the bowel area and fiducial markers were not generated with either of the sCT algorithms. In conclusion, sCT-algorithms were clinically usable on prostate treatments using 3T MR-only workflow. While AI-sCT showed better correspondence to TPCT than BM-sCT, it generated characteristic artifacts. As sCT algorithms perform well, we still recommend testing the sCT-algorithms with retrospective analyses from patient data prior to implementing sCT into the routine workflow to better understand the specific limitations and capabilities of these algorithms.

A comprehensive study on H2 loading/deloading with PdAg alloy thin films using in-situ synchrotron radiation X-ray diffraction

The present study gives a comprehensive picture of interaction of hydrogen with Pd0.54Ag0.46 and Pd0.88Ag0.12 alloy thin films, at RT, 50 °C, 100 °C, 150 °C and200 °C, based on the experiments reported in the present work. During hydrogenation, the diffraction peaks shifted towards a lower angle, indicating an expansion of the lattice due to hydrogen incorporation revealed by in-situ synchrotron XRD. The cycles of hydrogen absorption and desorption were fully reversible, and no hysteresis was observed in the synthesized films. Our experiments suggest that at room temperature the magnitude of peak-shift on hydrogenation is larger with lower concentrations of Ag in Pd. Additionally, the interaction of PdAg alloy with hydrogen was observed to be temperature dependent. Increased hydrogenation temperature reduces the hydrogen sticking coefficient, reducing the peak shift magnitude for both samples. Additionally, at higher temperatures, hydrogen absorption is higher in Pd54Ag46 having smaller crystallite sizes than in Pd88Ag12.

Affordability of healthy and water-saving dietary patterns in The Gambia

Abstract Background: Dietary modification has the potential to improve nutritional status and reduce environmental impacts of the food system. However, for many countries, the optimal composition of locally contextualised healthy and sustainable diets is unknown. The Gambia is vulnerable to climate-change-induced future water scarcity which may affect crop yields and the ability to supply healthy diets. This study identifies potential shifts in Gambian diets that could make diets healthier and reduce the associated agricultural water footprint, and assesses the cost and affordability implications of such dietary changes. &amp;#xD;Methods: Gambian Integrated Household Survey (IHS) food consumption data was combined with market prices, food expenditure and agricultural water footprint data. Current dietary patterns were compared with WHO dietary guidelines and optimised using linear programming to identify least-cost diets that met nutrition recommendations and reduced agricultural water use. Optimisation scenarios explored the maximum reduction in green water use that could be achieved with “culturally-acceptable” dietary shifts, and the magnitude of shifts required to maintain green water use at current levels. &amp;#xD;Results: On average, current diets provide adequate energy and have appropriate macronutrient composition. However, only 14% of households consume enough fruit and vegetables, and consumption of added sugars exceeds recommendations. With ‘culturally-acceptable’ changes in consumption, agricultural water use could decrease by 10–13% or increase by 9%, depending on baseline dietary pattern. Extreme dietary shifts will be required to maintain water use at 2015 levels with projected population growth. To meet WHO recommendations dietary costs would increase by 43% compared to the current baseline. Healthy and green water-saving diets would require 48–63% of average household expenditure to purchase, which is unaffordable for almost half of the population. Fruit and vegetables alone account for 31–40% of the cost of optimised diets compared to 12% of current diets.&amp;#xD;Conclusion: Dietary modification has the potential to improve the nutritional quality of Gambian diets while reducing agricultural water use, but the required changes are likely to be unaffordable for a large proportion of the population. Improving availability and affordability of nutritious foods—particularly fruit and vegetables—will be crucial for accessibility of healthy and sustainable diets in the Gambian population.&amp;#xD;

Predictive learning shapes the representational geometry of the human brain

Predictive coding theories propose that the brain constantly updates internal models to minimize prediction errors and optimize sensory processing. However, the neural mechanisms that link prediction error encoding and optimization of sensory representations remain unclear. Here, we provide evidence how predictive learning shapes the representational geometry of the human brain. We recorded magnetoencephalography (MEG) in humans listening to acoustic sequences with different levels of regularity. We found that the brain aligns its representational geometry to match the statistical structure of the sensory inputs, by clustering temporally contiguous and predictable stimuli. Crucially, the magnitude of this representational shift correlates with the synergistic encoding of prediction errors in a network of high-level and sensory areas. Our findings suggest that, in response to the statistical regularities of the environment, large-scale neural interactions engaged in predictive processing modulate the representational content of sensory areas to enhance sensory processing.

Detecting quantum vacuum fluctuations of the electromagnetic field

Abstract Quantum vacuum fluctuations of the electromagnetic field result in two signatures on a harmonically trapped charged particle: a shift from the natural trap frequency and generation of quantum coherences. We assess the role of the long-wavelength and rotating-wave approximations in estimating this frequency shift. We estimate the magnitude of the frequency shift using parameters from a single-electron cyclotron experiment and also demonstrate how the dependence of the frequency shift on the magnetic field of the cyclotron is tied to the rotating-wave approximation. We expect the frequency shift to be observable in future experiments. We also suggest a possible route to detecting vacuum-generated quantum coherences. These experiments should settle the debate on&amp;#xD;the choice of approximations and gauge in capturing the effect of the quantum vacuum fluctuations.

The Relationship between Event Boundary Strength and Pattern Shifts across the Cortical Hierarchy during Naturalistic Movie-viewing.

Our continuous experience is spontaneously segmented by the brain into discrete events. However, the beginning of a new event (an event boundary) is not always sharply identifiable: Phenomenologically, event boundaries vary in salience. How are the response profiles of cortical areas at event boundaries modulated by boundary strength during complex, naturalistic movie-viewing? Do cortical responses scale in a graded manner with boundary strength, or do they merely detect boundaries in a binary fashion? We measured "cortical boundary shifts" as transient changes in multivoxel patterns at event boundaries with different strengths (weak, moderate, and strong), determined by across-participant agreement. Cortical regions with different processing timescales were examined. In auditory areas, which have short timescales, cortical boundary shifts exhibited a clearly graded profile in both group-level and individual-level analyses. In cortical areas with long timescales, including the default mode network, boundary strength modulated pattern shift magnitude at the individual participant level. We also observed a positive relationship between boundary strength and the extent of temporal alignment of boundary shifts across different levels of the cortical hierarchy. In addition, hippocampal activity was highest at event boundaries for which cortical boundary shifts were most aligned across hierarchical levels. Overall, we found that event boundary strength modulated cortical pattern shifts strongly in sensory areas and more weakly in higher-level areas and that stronger boundaries were associated with greater alignment of these shifts across the cortical hierarchy.

Fish distribution shifts due to climate change in the Northeast Atlantic: Using a hierarchical filtering approach on marine-estuarine opportunist species

Marine-estuarine opportunist (MEO) species are fish that occur in the continental shelf and use estuaries and/or shallow coastal areas as nurseries. These commercially important resources are facing significant environmental modifications caused by direct and/or indirect anthropogenic climate change effects. In this study, we investigated the directionality and the magnitude of the distribution shifts (i.e., range size, gravity centroids, and margins) in marine environment suitability for six main MEO fish species within the Northeast Atlantic expected for the end of the 21st century. In the framework of this study, we have distinguished ‘sub-boreal’ from ‘sub-tropical’ species. The ‘hierarchical filters’ concept was adopted for modelling the potential species distributions and combined the predictions of i) a bioclimatic model with ii) a habitat model. The bioclimatic model is based on large-scale and time-variant variables while variables of the habitat model are fine-grained and time-invariant. Two Intergovernmental Panel on Climate Change (IPCC) scenarios are tested: an intermediate (SSP2-4.5) and a pessimistic one (SSP5-8.5). We applied this framework using international databases of biodiversity occurrences, ensemble forecasting producing consensual predictions, and innovative indices of distribution shifts. A visible north-westward shift was predicted for all six species in our study area. However, the northward expansion was greater for ‘sub-tropical’ than for ‘sub-boreal’ species due to faster gravity centroid displacement shifts and faster margins shifts. These range shifts may lead to major ecological impacts (e.g., changes in recruitment to estuarine and coastal nurseries, as well as changes in spawning grounds) that may alter populations' connectivity.

Multi-Beam Surveying Ocean Exploration Model and Applications

With the development of artificial intelligence, fiber Bragg grating (FBG) sensing technology has garnered increasing attention. This paper first proposes a surface reconstruction algorithm based on curvature information, which is applicable to two different sensor structures: implanted FBG sensors and whisker array sensors. The design and analysis of these sensors are based on a pure bending model, where the corresponding bending curvature is obtained by measuring the wavelength shift of the fiber Bragg grating at the measurement points. Next, the paper elaborates on the surface reconstruction algorithm for the implanted FBG sensor. This sensor contains FBG sensing points that are evenly distributed. Curvature information corresponding to the position can be obtained based on the direction and magnitude of the wavelength shift. The fiber bending is considered as a connection of multiple arc segments, and the coordinates of the sensing points are calculated in the Cartesian coordinate system using the properties of the tangents. The fiber bending curve is then reconstructed by connecting the arc segments in MATLAB. Finally, the paper provides a detailed introduction to the surface reconstruction algorithm for the whisker array sensor. When the whiskers bend, the FBGs fixed on them act as curvature sensors. The curvature is determined by the FBG wavelength shift, and the three-dimensional coordinates of the whisker tip relative to the base are calculated based on a geometric model. MATLAB is then used to connect the whisker tip coordinates, completing the construction of the surface.

Stark effect in MoSe&lt;sub&gt;2&lt;/sub&gt; monolayer heterostructure

The effect of a vertical electric field on photoluminescence of a MoSe2 monolayer encapsulated with hexagonal boron nitride is investigated. In the spectra, there is a quadratic shift of the photoluminescence lines of excitons and trions from the applied potential difference, as well as a change in their intensity. It is found that the magnitude of the Stark shift significantly exceeds the theoretically predicted one. It is found that the energy distance between the trion and exciton lines in the spectra varies with the magnitude of the external field, which is due to the dependence of the density of free charge carriers in the monolayer on the field. This effect made it possible to determine the density of free charge carriers in the monolayer, which varies with the field and lies in the range from 0.3–3.4⋅1012 cm–2.

Effect of the electronic properties of the side charges of neutral solvent molecules on the charges of the N and H atoms of the carbazole molecule: IR experiment and DFT calculations

The IR spectral parameters of the absorption band of the valence vibration of the NH bond of the carbazole molecule in several neutral solvents (n-hexane C6H14, carbon tetrachloride CCl4, chloroform CHCl3, benzene C6H6) have been measured. It has been experimentally established that the position of the maximum of the NH vibrational band of the carbazole molecule in solvents undergoes a low-frequency shift relative to the gas phase. This shift increases in the series C6H14, CCl4, CHCl3, C6H6. The change in the magnitude of the linear shift is well described by the Kirkwood-Bauer-Magat KBM ratio in C6H14, CCl4, CHCl3. The presence of a linear shift may indicate that only universal interactions take place. The deviation of this ratio of shift magnitude for carbazole in benzene is interpreted as a manifestation of intermolecular complexation. Quantum-chemical calculations of the position of the absorption band position of the valence vibration of the NH bond of the carbazole molecule in these solvents, carried out by the electron density functional method B3LYP/6-311++G (d,r) using the Gaussian 09W program package, also showed a low-frequency shift relative to the gas phase.It was found that for the carbazole molecule in the condensed phase relative to the gas phase the following effects of changing the magnitude of charges on atoms N13 and H14 take place: 1 – increase in the positive sign of the charge on both atoms; 2 – the change in charge magnitude is larger on the nitrogen atom than on the hydrogen atom for both solvents (whose molecules have a dipole moment ∼0: C6H14, CCl4); 3 – the chlorine containing environment has a greater effect on the charge change in the carbazole molecule than the proton containing environment (whose molecules have a dipole moment ∼0: C6H14, CCl4).The correlation between the change of charges on atoms N13 and H14 with the value of electronegativity ξ of the side solvent atoms was established.Thus, it is shown that the charges on the 13N and 14H atoms of the carbazole molecule undergo changes in the presence of universal interactions, and the magnitude of the charge change depends on the electronic properties of the side atoms of the nearest solvent molecules. A hypothesis is proposed to explain the different frequency shift of the NH vibrational frequency of the molecule for chlorine-containing and hydrogen-containing side atoms of neutral solvent molecules, which takes into account different values of ξ for nitrogen and hydrogen atoms.

Co+(C2H2)n Complexes Studied with Selected-Ion Infrared Spectroscopy and Theory.

Co+(C2H2)n (n = 1-6) complexes produced with laser vaporization in a supersonic molecular beam are studied with infrared photodissociation spectroscopy and computational chemistry. Infrared spectra are measured in the C-H stretching region using the method of tagging with argon atoms to enhance the photodissociation yields. C-H stretch vibrations for all clusters studied are shifted to lower frequencies than those of the well-known acetylene vibrations from ligand → metal charge transfer interactions. The magnitude of the red shifts decreases in the larger clusters as the interaction is distributed over more ligands. Computational studies identify various unreacted complexes with individual acetylene ligands in cation-π bonding configurations as well as reacted isomers in which ligand coupling reactions have taken place. Infrared spectra are consistent only with unreacted structures, even though the formation of reacted structures such as the metal ion-benzene complex is highly exothermic. Large activation barriers are predicted by theory along the reaction coordinates for the n = 2 and 3 complexes, which inhibit reactions in these smaller clusters, and this situation is presumed to persist in larger clusters.

7861 Estrogen Receptor Alpha Regulates the Sex Difference in Jet Lag in Mice

Abstract Disclosure: M.A. Venegas: None. N. Westray: None. J.S. Pendergast: None. The circadian system aligns 24-hour cycles of internal biological processes with the environmental light-dark cycle. Abrupt shifts in the timing of the light-dark cycle that occur during travel across time zones misalign internal circadian clocks with the environment and cause jet lag. The symptoms of jet lag subside when circadian clocks resynchronize to the new light-dark cycle. Female mice in proestrus resynchronize to shifted light-dark cycles faster than males. The objective of this study was to investigate the estrogen signaling mechanisms underlying this sex difference in jet lag in mice. We measured wheel-running activity rhythms in C57BL/6J male and female wild-type (WT) and ERα knockout (ERαKO) mice. Female WT mice had 2-fold greater daily activity than male mice. Disabling the function of ERα ablated the sex difference in daily activity; both male and female ERαKO mice had markedly reduced activity compared to WT mice. Next, we advanced the timing of the light-dark cycle by 6 hours to simulate eastward travel. Female WT mice resynchronized to the new light-dark cycle faster than WT males. This sex difference was abolished in ERαKO mice. The rate of resynchronization was slower in female ERaKO mice compared to WT females and was indistinguishable from males. We next investigated 2 putative mechanisms underlying the accelerated rate of resynchronization in WT females. First, mice with faster endogenous clocks resynchronize to new light-dark cycles faster. However, we found that the velocity of the endogenous clock (circadian period) did not differ between WT and ERαKO male and female mice. Second, mice with greater phase advances to light exposure in the late night also resynchronize faster. To determine the magnitude of phase advances, we housed mice in constant darkness and then exposed them to a 15-minute light pulse during the late subjective night. We found no differences in the magnitudes of phase shifts between WT and ERαKO male and female mice. Together these studies show that ERα regulates the rate of resynchronization to shifted light-dark cycles in female mice but does not do so by altering conventional circadian rhythm parameters. Uncovering the mechanisms underlying the sex difference in resynchronization to shifted light-dark cycles can be used to develop strategies to alleviate jet lag and shift work symptoms. Presentation: 6/3/2024

Deconstructing the frame effect.

The perception of an object's location is profoundly influenced by the surrounding dynamics. This is dramatically demonstrated by the frame effect, where a moving frame induces substantial shifts in the perceived location of objects that flash within it. In this study, we examined the elements contributing to the large magnitude of this effect. Across three experiments, we manipulated the number of probes, the dynamics of the frame, and the spatiotemporal relationships between probes and the frame. We found that the presence of multiple probes amplified the position shift, whereas the accumulation of the frame effect over repeated motion cycles was minimal. Notably, an oscillating frame generated more pronounced effects compared to a unidirectional moving frame. Furthermore, the spatiotemporal distance between the frame and the probe played pivotal roles, with larger shifts observed near the leading edge of the frame. Interestingly, although larger frames produced stronger position shifts, the maximum shift occurred almost at the same distance relative to the frame's center across all tested sizes. Our findings suggest that the number of probes, frame size, relative probe-frame distance, and frame dynamics collectively contribute to the magnitude of the position shift.

Differential Effects of Light and Dark Phase Modifications on Jet Lag Adaptability in Mice

ABSTRACTIn chronobiology, shifting light/dark cycles is a common method to disrupt circadian rhythms. While the direction and magnitude of a phase shift (e.g., +6 denoting a 6‐h advanced shift) dictate the temporal change before and after the shift, little attention has been paid to the duration and relative proportion of daytime and nighttime during the shift, leading to a critical, unexamined variable in circadian research. In this study, we introduce the concepts of “L‐shift” (longer light phase on the shift day) and “D‐shift” (longer dark phase), and investigate how these variations impact the adaptability of mice to jet lag. By examining multiple phase shifts (12L vs. 12D, +6L vs. +6D, −6L vs. −6D), we demonstrate that L‐shifts not only facilitate faster adaptation but also significantly reduce the severity of sepsis in a jet lag‐sensitive lipopolysaccharide‐induced sepsis model. Further investigations with additional phase shifts at 1‐h intervals (+8 to +11) reinforced the enhanced fitness of mice under L‐shifts. Mechanistically, L‐shifts were found to increase sleep duration, thereby improving circadian entrainment, with sleep deprivation nullifying the adaptability differences between lighting protocols. These findings underscore a previously unrecognized factor in circadian biology and suggest that optimizing lighting protocols could profoundly improve adaptability to circadian disruptions. This research opens new avenues for enhancing therapeutic strategies and refining experimental designs in the field of chronobiology.

Gelatin-Coated High-Sensitivity Microwave Sensor for Humidity-Sensing Applications.

In this paper, the humidity-sensing characteristics of gelatin were compared with those of poly(vinyl alcohol) (PVA) at L-band (1 ~ 2 GHz) microwave frequencies. A capacitive microwave sensor based on a defected ground structure with a modified interdigital capacitor (DGS-MIDC) in a microstrip transmission line operating at 1.5 GHz without any coating was used. Gelatin is a natural polymer based on protein sourced from animal collagen, whereas PVA is a high-sensitivity hydrophilic polymer that is widely used for humidity sensors and has a good film-forming property. Two DGS-MIDC-based microwave sensors coated with type A gelatin and PVA, respectively, with a thickness of 0.02 mm were fabricated. The percent relative frequency shift (PRFS) and percent relative magnitude shift (PRMS) based on the changes in the resonant frequency and magnitude level of the transmission coefficient for the microwave sensor were used to compare the humidity-sensing characteristics. The relative humidity (RH) was varied from 50% to 80% with a step of 10% at a fixed temperature of around 25 °C using a low-reflective temperature and humidity chamber manufactured with Styrofoam. The experiment's results show that the capacitive humidity sensitivity of the gelatin-coated microwave sensor in terms of the PRFS and PRMS was higher compared to that of the PVA-coated one. In particular, the sensitivity of the gelatin-coated microwave sensor at a low RH from 50% to 60% was much greater compared to that of the PVA-coated one. In addition, the relative permittivity of the fabricated microwave sensors coated with PVA and gelatin was extracted by using the measured PRFS and the equation was derived by curve-fitting the simulated results. The change in the extracted relative permittivity for the gelatin-coated microwave sensor was larger than that of the PVA-coated one for varying the RH.

Temperature-dependent predation predicts a more reptilian future.

Diversity increases toward the tropics, but the strength of this pattern diverges with thermoregulatory strategy. Synthesizing over 30,000 species distributions, we quantified patterns of richness in terrestrial vertebrates, and present evidence for a latitudinal gradient of community composition. We observe a two orders of magnitude shift in comparative diversity with temperature, from endothermic mammal and avian dominance near the poles, toward ectothermic reptile and amphibian majority in the tropics. Next, we provide mechanistic support for a corresponding latitudinal gradient of predatory interactions. Using automated video tracking in >4500 trials, we show that differences in thermal sensitivity of locomotion in endothermic predators and ectothermic prey favors endotherms in colder environments and yields theoretically predicted foraging outcomes across thermal conditions, including the number of strikes, the distance traveled, and the time to capture prey. We also present evidence that endotherms use thermal cues to anticipate prey behavior, modulating the impact of temperature. Finally, we integrate theory and data to forecast future patterns of diversity, revealing that as the world get warmer, it will become increasingly reptilian. Overall, our results point toward a broad reorganization of vertebrate diversity with latitude, elevation, and temperature: from endotherm dominance in cold systems toward ectotherm dominance in warm.

Charmonia in an unquenched quark model

In this work, we study the charmonium spectrum within an unquenched quark model including coupled-channel effects. In couple-channel calculations, we include all of the opened charmed meson channels with the once-subtracted method, meanwhile we adopt a suppressed factor to soften the hard vertices given by the P03 model in the high momentum region. We obtain a good description of both the masses and widths for the well-established states in the charmonium spectrum. Furthermore, we give predictions for the higher S-, P-, and D-wave charmonium states up to mass region of ∼5.0 GeV. The magnitude of mass shifts due to the coupled-channel effects is estimated to be about 10s MeV. Although many decay channels are opened for the higher charmonium states, they are relatively narrow states. Their widths scatter in the range of ∼10s–100 MeV. Many charmoniumlike states, such as χc1(4274), χc0(3915), χc0(4500), χc0(4700), X(4160), X(4350), Y(4500), and ψ(4660)/Y(4710), can be accommodated by the charmonium spectrum when the unquenched coupled-channel effects are carefully considered. Published by the American Physical Society 2024

High-Q resonances based on BIC in graphene-dielectric hybrid double-T metasurfaces for terahertz modulation and sensing

In recent years, there has been a growing interest in bound states in the continuum (BIC) in metasurfaces. One particular area of focus is achieving high-quality (Q) factor resonance, as this is crucial for enhancing the performance of refractive index sensors. In this study, a graphene-dielectric hybrid metasurface that supports the bound states in the continuum is proposed. By varying the width of the dielectric rectangle, quasi-BIC resonances with a high Q factor can be excited, and the Q factor can reach 752724.95 and 272004.759 respectively. The analysis of multipole decomposition reveals that the two quasi-BIC resonances are predominantly influenced by the electric quadrupole and magnetic dipole, respectively. Moreover, the transmittance of the resonance point can be changed rapidly with the change of the chemical potential of graphene, so the function of modulation can be realized by changing the chemical potential of graphene. Based on these findings, we have designed a terahertz wave modulator, which exhibits modulation depths of 98.1% and 99.9% at the two resonance peaks, respectively. The corresponding chemical potential shifts are 50 meV and 0.5 eV. Additionally, we have investigated the sensing performance of the metasurface. By analyzing the magnitude of the frequency shifts of the quasi-BIC resonance peaks at different gas refractive indexes, we have determined sensitivities of 740 GHz RIU−1 and 630 GHz RIU−1 at the two resonance peaks. The maximum figure of merit (FOM) values are 132911.39 RIU−1 and 45000 RIU−1, respectively. This research serves as a valuable reference for the design of dynamic optical modulators and sensors operating in the terahertz band.

Advances in breeding phenology outpace latitudinal and elevational shifts for North American birds tracking temperature.

Terrestrial species can respond to a warming climate in multiple ways, including shifting in space (via latitude or elevation) and time (via phenology). Evidence for such shifts is often assessed independent of other temperature-tracking mechanisms; critically, no study has compared shifts across all three spatiotemporal dimensions. Here we used two continental-scale monitoring databases to estimate trends in the breeding latitude (311 species), elevation (251 species) and phenology (111 species) of North American landbirds over 27 years, with a shared pool of 102 species. We measured the magnitude of shifts and compared them relative to average regional warming (that is, shift ratios). Species shifted poleward (1.1 km per year, mean shift ratio 11%) and to higher elevations (1.2 m per year, mean shift ratio 17%), while also shifting their breeding phenology earlier (0.08 days per year, mean shift ratio 28%). These general trends belied substantial variation among species, with some species shifting faster than climate, whereas others shifted more slowly or in the opposite direction. Across the three dimensions (n = 102), birds cumulatively tracked temperature at 33% of current warming rates, 64% of which was driven by advances in breeding phenology as opposed to geographical shifts. A narrow focus on spatial dimensions of climate tracking may underestimate the responses of birds to climate change; phenological shifts may offer an alternative for birds-and probably other organisms-to conserve their thermal niche in a warming world.

Morphologic Response in Femoral Cartilage During and After 40-Minute Treadmill Running.

It is unclear whether the response in femoral cartilage to running at different intensities is different. To examine the acute patterns of deformation and recovery in femoral cartilage thickness during and after running at different speeds. Crossover study. Laboratory. A total of 17 healthy men (age = 23.9 ± 2.3 years, height = 173.1 ± 5.5 cm, mass = 73.9 ± 8.0 kg). Participants performed a 40-minute treadmill run at speeds of 7.5 and 8.5 km/h. Ultrasonographic images of femoral cartilage thickness (intercondylar, lateral condyle, and medial condyle) were obtained every 5 minutes during the experiment (40 minutes of running followed by a 60-minute recovery period) at each session. Data were analyzed using analysis of variance and Bonferroni- and Dunnett-adjusted post hoc t tests. To identify patterns of cartilage response, we extracted principal components (PCs) from the cartilage-thickness data using PC analysis, and PC scores were analyzed using t tests. Regardless of time, femoral cartilage thicknesses were greater for the 8.5-km/h run than the 7.5-km/h run (intercondylar: F1,656 = 24.73, P < .001, effect size, 0.15; lateral condyle: F1,649 = 16.60, P < .001, effect size, 0.16; medial condyle: F1,649 = 16.55, P < .001, effect size, 0.12). We observed a time effect in intercondylar thickness (F20,656 = 2.15, P = .003), but the Dunnett-adjusted post hoc t test revealed that none of the time point values differed from the baseline value (P > .38 for all comparisons). Although the PC1 and PC2 captured the magnitudes of cartilage thickness and time shift (eg, earlier versus later response), respectively, t tests showed that the PC scores were not different between 7.5 and 8.5 km/h (intercondylar: P ≥ .32; lateral condyle: P ≥ .78; medial condyle: P ≥ .16). Although the 40-minute treadmill run with different speeds produced different levels of fatigue, morphologic differences (<3%) in the femoral cartilage at both speeds seemed to be negligible.