Absolute Intensity Research Articles

SARS-CoV-2 vaccination response in pediatric oncology patients.

There remains limited knowledge about the immune response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination in pediatric oncology patients, which is essential to provide counseling and risk adaptation in this vulnerable population. The goal of this study was to understand immunogenicity after vaccination in pediatric oncology patients, and determine if certain clinical factors impacted response. Patients 0-25years of age with a diagnosis of cancer and actively receiving therapy were enrolled on study. We excluded patients who were completely vaccinated prior to their cancer diagnosis. Blood samples were collected pre-vaccination, as well as 2, 4-6, and 8-12weeks after vaccination. Healthy children who were fully vaccinated enrolled as controls. Clinical data and complete blood counts around time of vaccination were collected. To study B- and T-cell immunity, we measured neutralizing antibodies by enzyme-linked immunoassay and interferon gamma secretion by enzyme-linked immunospot, respectively. Twenty-six patients enrolled on study, for which 11 were evaluable oncology patients and seven were healthy controls. Adequate B-cell response was seen in 36.4% of patients, and adequate T-cell response in 77.8% of patients. Numbers were too small to detect differences based on malignancy type. There was no differences in immunity based on absolute lymphocyte count (ALC) or intensity of therapy. Pediatric oncology patients have a suboptimal immune response to SARS-CoV-2 vaccination. Booster doses will be imperative to provide optimal protection against COVID-19; however, blood counts may not be a useful guide to optimize the time of administration.

Accelerometer-measured absolute versus relative physical activity intensity: cross-sectional associations with cardiometabolic health in midlife

BackgroundObservational studies investigating the association between accelerometer-measured physical activity and health all use absolute measures of physical activity intensity. However, intervention studies suggest that the physical activity intensity required to improve health is relative to individual fitness. The aim of this study was to investigate the associations between accelerometer-measured absolute and relative physical activity intensity and cardiometabolic health, and what implications these associations may have on the interpretation of health-associated physical activity.MethodsA sample of the cross-sectional Swedish CArdioPulmonary bioImage Study (SCAPIS) consisting of 4,234 men and women aged 55–64 years was studied. Physical activity intensity was measured by accelerometry and expressed as absolute (e.g., metabolic equivalents of task) or relative (percentage of maximal oxygen consumption). Fitness was estimated by the submaximal Ekblom-Bak test. A composite (‘metabolic syndrome’) score combined measures of waist circumference, systolic blood pressure, high-density lipoprotein, triglycerides, and glycated hemoglobin. Associations of absolute and relative physical activity intensity with the health indicators (i.e., fitness and metabolic syndrome score) were studied by partial least squares regression. Analyses were stratified by fitness level.ResultsBoth absolute and relative physical activity intensity associated with the health indicators. However, the strongest associations for absolute intensity varied depending on fitness levels, whereas the associations for relative intensity were more synchronized across fitness groups. The dose–response relationship between moderate-to-vigorous intensity and the health indicators was stronger for relative than for absolute intensity. The absolute and relative moderate-to-vigorous intensity cut-offs intersected at the 5th fitness percentile, indicating that the absolute intensity cut-off is too low for 95% of individuals in this sample. While 99% of individuals fulfilled the general physical activity recommendations based on absolute intensity measures, only 21% fulfilled the recommendations based on relative intensity measures. In relation to a “sufficient” fitness level, 9% fulfilled the recommendations.ConclusionsAccelerometer-measured relative physical activity intensity represents the intensity related to health benefits regardless of fitness level. Traditional absolute moderate intensity accelerometer cut-offs are too low for most individuals and should be adapted to the fitness level in the sample studied. Absolute and relative physical activity intensity cannot be used interchangeably.

Liquid scintillation efficiencies, gamma-ray emission intensities, and half-life for Gd-153

Gadolinium-153 was standardized for activity by live-timed anticoincidence counting and an ampoule was submitted to the international reference system (SIR). Absolute emission intensities for the main γ rays were determined with calibrated high-purity germanium (HPGe) and lithium-drifted silicon (Si(Li)) detectors. A revised decay scheme is indicated, with no probability of direct electron capture to the 153Eu ground state. Triple-to-double coincidence ratio (TDCR) efficiency curves indicate that the revised decay scheme is consistent with experiment. Half-life measurements agree with a previous NIST determination and show no sensitivity to chemical environment.

Effect of Kinesio taping versus mechanical cervical traction combined with physiotherapy program on chronic neck pain in young female university students.

Mechanical neck pain is common among young female university students and can lead to disability and reduced physical activity. The aim of this study was to compare the effect of Kinesio taping (KT) to mechanical cervical traction (MCT) on young female university students with chronic neck pain. Sixty young female university students with mechanical neck pain participated in this study; their ages ranged from 19 years to 23 years. They were assigned to three equal groups: the control group (A) received infrared, massage, stretching, and strengthening exercises three days per week for 6 weeks. Experimental group B received cervical traction in addition to the same program as the control, and experimental group C received KT in addition to the same program as the control group. Absolute pain intensity by the visual analogue scale (VAS) and neck disability index (NDI) were measured pre-and post-treatment intervention. Data were gathered at baseline, and after 6 weeks of intervention for three groups. The MANOVA test showed a significant reduction in NDI and pain level after 6 weeks between pre-and post-treatment intervention in group B ( and , respectively). There was a significant reduction in pain after 6 weeks in group C. There was also a significant reduction in NDI and pain level after 6 weeks in group B versus control group ( and , respectively). In addition, a significant reduction in pain level and NDI after 6 weeks was detected in group B compared to group C (, , respectively) while a significant reduction in pain level only between the control group (A) and group C was detected (). In young female university students with mechanical neck pain, cervical traction combined with physiotherapy program was found to be more effective than KT with physiotherapy program or physiotherapy program alone in reducing pain and enhancing functional abilities after 6 weeks. This will help physiotherapists make more informed decisions concerning the clinical effects of MCT.

Insights into quantitative evaluation technology of PM2.5 transport at multi–perspective and multi–spatial and temporal scales in the north China plain

Cross-border transport is a crucial factor affecting air quality, while how to quantify the transport contribution through different technologies at multi–perspective and multi–scale have not been fully understood. This study established three quantification techniques, and conducted a systematic assessment of PM2.5 transport over the North China Plain (NCP) based on numerical simulations and vertical observations. Results suggested that the annual local emissions, inter–urban and outer–regional transport contributed 44.5%–64.6%, 15.2%–27.9% and 18.0%–28.2% of total surface PM2.5 concentrations, respectively, with transport intensity stronger in July and April, yet weaker in January and October. The southwest–northeast, northeast–southwest, and southeast–northwest were three prevailing transport directions near the surface. By comparison, the annual PM2.5 transport contribution below the atmospheric boundary layer height increased by 16.8%–24.5% in Beijing, Tianjin and Shijiazhuang, with inter–urban and outer–regional contribution of 29.8%–32.1% and 18.5%–23.1%. Furthermore, observed fluxes from fixed-point and vehicle-based mobile lidar were in good agreement with the simulated flux. PM2.5 net flux intensity varied with height, with generally larger at the middle- and high-altitude layer than that of low-altitude layer. In the early, during and late period of haze peak formation (Stage Ⅰ, Ⅱ, Ⅲ, respectively), the largest absolute flux intensity on average was Stage Ⅱ (566.7 t/d), followed by Stage Ⅲ (307.0 t/d) and Ⅰ (191.4 t/d). Besides, external transport may dominate the second concentration peak, while local emissions may play a more vital role in the first and third peaks. It has been noted that joint prevention and control measures should be proposed 1–2 days before reaching PM2.5 extremes. These findings could improve our understanding of transport influence mechanism of PM2.5 and propose effective emission reduction measures in the NCP region.

Glutaraldehyde-based desensitizer does not influence postoperative sensitivity and clinical performance of posterior restorations: A 24-month randomized clinical trial.

To evaluate the influence of a glutaraldehyde-based desensitizer (GL) on postoperative sensitivity (POS) in posterior bulk-fill resin composite restorations using an adhesive applied in the self-etch (SE) and etch-and-rinse (ER) strategies; and to assess the clinical performance of the restorations. Posterior resin composite restorations (n=228) at least 3mm deep were inserted in 57 subjects using a split-mouth design. The adhesive was applied with/without prior application of a GL. A resin composite was used for all restorations. Spontaneous POS (risk and intensity), as well as POS caused by stimulation with an air blast and assess the response to horizontal and vertical percussion was assessed using two scales in the baseline and after 7, 14, and 30 days. In addition, some parameters were evaluated using FDI criteria up to 24 months of clinical service. No significant POS was observed (p>0.05). A higher absolute risk and intensity of spontaneous POS was observed within 7 days (35.1%), without statistically significant differences among groups. At 24 months 5 restorations were considered clinically unsatisfactory, and 73 restorations showed minor discrepancies in adaptation, with no significant differences between groups (p>0.05). A GL agent does not influence POS in posterior restorations with bulk-fill resin composite. It may be considered a dispensable clinical step in the restorative protocol.

Pitch Angle Distributions of Energetic Particles Near Callisto

AbstractThe Galileo spacecraft performed close flybys of the moon Callisto between 1996 and 2001. We reanalyzed particle data of the energetic particles detector onboard Galileo and derived pitch angle distributions in the energy range of several keV to MeV during Callisto flybys C3, C9, C10, and C30. We establish that field‐aligned beams observed during the flyby periods are more likely to originate from Callisto's magnetospheric interaction rather than by independent magnetospheric processes. These beams are prominent only during flyby C3, they come mainly from the North, and connect the moon and the ionosphere of Jupiter. For short intervals they have also been observed propagating from the South. The beams are regularly unidirectional and typically extend to 300 keV in energy, occasionally reaching above 600 keV. Energetic particle depletions in Callisto's wake during the downstream flybys are not at all obvious, even at low altitudes and in the wake center. The signature of the wake becomes more apparent when energetic particle observations are organized in pitch angle. In that case, pitch angle distribution minima at 90 deg can be discerned in some flybys, however, not always associated with a profound drop in the absolute signal intensity. They instead indicate that field‐aligned particle flux within the wake is higher. Outside the wake these minima continue in an energy‐dependent disturbed region toward Jupiter which seems to be at least partially collocated with Alfvén‐wing structures as predicted from magnetohydrodynamic simulation results or simple flyby geometry considerations.

O.4.2-10 What can one minute of the day tell about physical capacity?

Abstract Introduction High cardiorespiratory fitness (CRF) allows individuals to perform daily activities and operate at higher intensity levels. This study investigates the association between the CRF and peak intensity of physical activity (PA) in absolute and relative terms. Absolute intensity measures the amount of energy expended per unit of time during an activity, while relative intensity reflects the proportion of an individual's maximal capacity. Methods 1952 adults (803 men, 1149 women) aged 20-69 years participated in the FinFit2017-study. Their CRF was predicted with 6 min walking test, and they wore the accelerometer for at least four days with a minimum of 24 h/day during the seven days measurement period. The participants were divided into CRF thirds by five age groups and sex. Acceleration data were analyzed in 6s epochs and intensity in MET (metabolic equivalent) values were calculated for each epoch. MET values were smoothed with a 1min exponential moving average and the highest daily value was recorded (peakMET). Analysis was done to the weekly mean of daily peakMET values both in absolute and relative terms. Results The CRF correlated significantly with absolute peakMET (r = 0.500) and relative peakMET (r=-0.456). In absolute terms, the highest CRF third had the highest peakMET value for men (6.5±1.8; 6.0±1.5; 5.2±1.2) and women (6.3±1.4; 5.8±1.1; 5.2±1.0). In relative terms, the highest CRF third utilized least of their aerobic capacity (men: 53±14%; 56±13%; 61±15%) and (women: 58±12%; 60±12%; 70±16%). Conclusion One minute of the day can provide valuable information about the individual’s CRF and the level of effort required during PA. Higher measured absolute peakMET may indicate higher CRF, as more fit individuals can sustain higher levels of PA. When an individual’s CRF is taken into account, individuals with lower CRF have to utilize more of their aerobic capacity. Thus, high CRF provides a possibility to operate at higher intensity levels and protects from strenuous PA during daily routines.

Are environmental, social and governance (ESG) ratings reliable indicators of emissions outcomes? A case study of the airline industry

AbstractWe analyse environmental ratings and emissions scores for commercial airlines from several major environmental, social and governance ratings providers. Specifically, we investigate whether emissions scores capture and predict absolute carbon emissions and emissions intensity levels, and whether scores are consistent across providers. This builds on existing literature by evaluating the predictive ability of ratings over significantly longer periods than past studies, examining within‐industry ratings disagreement for carbon emissions scores, and using an industry‐specific emissions intensity metric. Data covers 57 airlines from 2012 to 2021. Cross‐sectional and panel regressions are estimated to investigate whether ratings capture and predict carbon emissions data. We find no evidence that emissions scores capture or predict reported carbon emissions, and find that scores from different providers diverge substantially. Persistent shortcomings may undermine trust in the ratings industry, create trade‐offs between emissions abatement and ratings improvement, and hinder the incorporation of climate‐related information in capital allocation decisions.

Absolute Versus Relative Physical Activity Intensity During Pregnancy And Postpartum in US Women

Absolute Versus Relative Physical Activity Intensity During Pregnancy And Postpartum in US Women

Can quantifying the relative intensity of a person’s free-living physical activity predict how they respond to a physical activity intervention? Findings from the PACES RCT

ObjectivesTo determine whether quantifying both the absolute and relative intensity of accelerometer-assessed physical activity (PA) can inform PA interventions. We hypothesised that individuals whose free-living PA is at a low...

Retrospective Assessment of Greenhouse Gas Emissions from the Beef Sector in Greece and Potential Mitigation Scenarios

Although beef production is one of the most valuable drivers of the global livestock economy, it is considered the main contributor to GHG emissions derived from livestock. This study’s objectives were to estimate the GHG emissions (expressed in carbon dioxide equivalents; CO2-eq) from the beef sector in Greece at the national and prefecture levels during the period 2011–2021 and to explore potential mitigation scenarios. The Tier 1 and 2 methodologies were implemented to estimate the GHG emissions. The total estimated emissions increased over the study period. Although both methodologies captured similar trends in the changes in GHG emissions, the Tier 2 estimations revealed lower emissions and fluctuations due to the different and more precise computational approaches. At the prefecture level, fluctuations in emissions were also noted. However, specific regions showed higher increases in emissions. The observed increase in emissions, in terms of either absolute values (Gg CO2-eq) or intensities (Kg CO2-eq/Kg produced beef carcass), is of utmost importance, and further mitigation strategies should be considered. The regression analysis showed a good predictive ability for emissions, using the number of livestock animals as the input. The equations derived from this analysis could be further used as first-approach tools for capturing future emissions at the national level before proceeding with more elaborate approaches. The different scenarios examined in response to the sector’s challenges showed moderate changes in GHG emissions. Depending on national priorities, such scenarios could serve as pilot case studies, which may assist stakeholders in improving the sustainability of the sector in the future.

Petroleomics by design of experiments in ESI(±)FT-ICR MS analysis

The Fourier Transform Ion Cyclotron Resonance mass spectrometer (FT-ICR MS) is an efficient and widely used analytical instrument for characterizing complex organic mixtures at the molecular level. The Electrospray ionization (ESI) source is commonly used for identifying heteroatomic compounds (N, O, S) in crude oil. The high complexity of the sample provides a wealth of information, and therefore, processing and visualization programs are used to facilitate data interpretation. Several experimental configurations of parameters exist for the acquisition of ESI(+)FT-ICR MS and ESI(-)FT-ICR MS of crude oils. In this context, the design of experiments can help obtain optimal test conditions. The objective of this work was to identify the most significant experimental parameters among the 11 available (concentration, skimmer, time of flight (TOF), flow rate, ion accumulation time (IAT), accumulated scans (scans), dry temperature, capillary, dry gas, nebulizer, and collision voltage (CV)) for the acquisition of ESI(±)FT-ICR MS in Petroleomics using design of experiments by Plackett Burman and full design. Global desirability was used as a response parameter obtained from MS data (resolution, signal-to-noise ratio, signal-to-charge ratio signal with highest absolute intensity, total signals, low mass error, and high mass error). Additionally, responses from the mass spectra processing program were also used (the number of molecular formulas, molecular formulas of the majority class, average error, assignment percentage, amount of DBE in the plot of DBE versus carbon number (CN), and the relationship between the number of zero intensities and the number of DBE values in the plot of DBE versus CN). The study found that concentration and flow rate were the most significant experimental parameters for ESI(+), while for ESI(-), TOF and CV were the most significant experimental parameters. Lower concentration (0.1–0.5 mg/mL) and higher flowrate (5–6 µL/min) improved the desirability by ESI(+), higher values of CV (50 V) improved the desirability by ESI(-) for crude oil analysis.

Fit-free analysis of fluorescence lifetime imaging data using chemometrics approach for rapid and nondestructive wood species classification

Abstract Conventional fluorescence spectroscopy has been suggested as a valuable tool for classifying wood species rapidly and non-destructively. However, because it is challenging to conduct absolute emission intensity measurements, fluorescence analysis statistics are difficult to obtain. In this study, another dimension of fluorescence, that is, fluorescence lifetime, was further evaluated to address this issue. A time-resolved fluorescence spectroscopic measurement system was first designed, mainly using a streak camera, picosecond pulsed laser at 403 nm, and a spectroscope, to collect the fluorescence time-delay (FTD) profiles and steady-state fluorescence intensity (FI) spectra simultaneously from 15 wood species. For data analysis, principal component analysis was used to “compress” the mean-centered FTD and FI spectra. Then, support vector machine classification analysis was utilized to train the wood species classification model based on their principal component scores. To avoid overfitting, ten-fold cross-validation was used to train the calibration model using 70 % of the total samples, and the remaining 30 % hold-out validation was used to test its reproducibility. The cross-validation accuracies were 100 % (5 softwoods) and 96 % (10 hardwoods), with test-validation accuracies of 96 % and 89 %.

New line intensities for the far infrared bands of the Trans- and Cis-conformer of nitrous acid (HONO), new determination of the Trans-Cis conformer barrier and its impact on the astrophysical detection of nitrous acid in protostellar clouds

The first goal of this work is to improve the determination of the energy difference (ΔECis-Trans) between the ground vibrational state of the Cis- and Trans-HONO conformers of nitrous acid. For this, high resolution spectra were recorded in the 50–200 cm−1 spectral region at three different temperatures, 240, 270 and 296 K. The relative line intensities for the B-type transitions of pure rotational bands of Trans-HONO and Cis-HONO achieved from our measurements were combined in least squares fit computations to those measured previously by Sironneau et al. [Sironneau V, Flaud JM, Orphal J, Kleiner I, Chelin P. Absolute line intensities of HONO and DONO in the far-infrared and re-determination of the Energy Difference between the trans- and cis-species of nitrous acid. J Mol Spectrosc 2010;259:100–104]. In this way, we can significantly improve the accuracy on the HONO conformer energy difference, with a value for ΔECis-Trans = 95.8 ± 9.2 cm−1 compared to SIRΔECis-Trans = 99 ± 25 cm−1 in the previous study of Sironneau et al. The second goal is to generate a line list with “absolute” line intensities for the pure rotational bands in the far infrared region of Trans-HONO and Cis-HONO, with both A- and B-type transitions. This new line list proved to be more robust for an improved detection of HONO in astrophysical objects [Coutens A, Ligterink NFW, Loison JC, Wakelam V, Calcutt H, Drozdovskaya MN, Jørgensen JK, Müller HSP, Van Dishoeck EF, Wampfler SF. The ALMA-PILS survey: First detection of nitrous acid (HONO) in the interstellar medium. Astronomy & Astrophysics 2019;623:L13].

Spectral Quality Assessment Strategy Based on the 13C-Isotopic Pattern for the Fourier Transform Ion Cyclotron Resonance Mass Spectra of Dissolved Organic Matter.

The interpretation of data and optimization spectral acquisition of dissolved organic matter (DOM) by ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) have been challenging due to the varied instrument performances among laboratories and the complex chemical characteristics of DOM. However, a universal spectral optimization strategy for FT-ICR MS spectra is still unavailable. The results of this study showed that the number, intensity, and resolving power of all assigned peaks increased with the ion accumulation time (IAT) and DOM concentrations within a reasonable range. The space-charge effect induced by the excess ions in the ICR cell can deteriorate the data quality of the FT-ICR MS spectra, which could be inspected by examining the mass errors and intensity deviation of the monoisotopic and 13C-isotopic peaks based on the 13C-isotopic pattern. The maximum absolute mass error and 13C-isotopic pattern-based intensity deviation are two critical criteria for inspecting the space-charge effect, which was suggested to be 2.0 ppm and 20%, respectively. Therefore, a novel strategy based on the 13C-isotopic pattern has been proposed in this study to optimize the FT-ICR MS spectra of DOM based on their wide occurrence of monoisotopic and 13C-isotopic signals. This optimization strategy has laid the fundamentals for the method development of FT-ICR MS and could be extended to different FT-ICR MS instruments and various organic complex mixtures.

Homoleptic Alkynylpyridinium Au(I) Complexes as Organometallic ‘D‐π‐A’ Chromophores

A series of terminal acetylenes bearing methylpyridinium acceptor group attached to the alkynyl unit with different π-conjugated aromatic linker have been synthetized. These alkynylpyridinium salts are efficient 'push-pull' chromophores demonstrating bright UV-vis fluorescence with quantum yields up to 70%. The homoleptic bis-alkynyl Au(I) complexes based on these alkynylpyridinium ligands demonstrate complicated photophysical behavior including dual emission in solution. The variation of the linker allows one to tune the intersystem charge transfer and thus to change the electronic and photophysical properties of the organogold 'D-π-A' system. This study demonstrates that absolute and relative intensities of the bands in emission spectra and their energies are responsive to solvent system and anion nature even in case of weakly coordinative anions. TDDFT calculations show that the transitions related to emission of the complex cations are strongly associated with the hybrid MLCT/ILCT charge transfer, thus demonstrating that the complex molecule acts as a unified 'D-π-A' system.

Fast gas chromatography-tandem mass spectrometry under milder electron ionization conditions for the assay of vitamin D metabolites in human serum

The proposed research was focused on the development of a gas chromatography-tandem mass spectrometry (GC-QqQ-MS) method under milder electron ionization (EI) conditions for the assay of vitamin D metabolites in human serum. Efficiency of three different silylation agents was evaluated for the conversion of vitamin D species into trimethylsilyl (TMS) derivatives, among which N-methyl-N-(trimethylsilyl)-trifluoroacetamide (MSTFA) proved to be the most effective. Indeed, the MSTFA reagent was able to convert in TMS ether even the 25-hydroxyl vitamin D derivative that, as known, possesses steric hindrance problems. The separation of vitamin D compounds was obtained in about 11.5 min using a narrow-bore column of dimensions 30 m × 0.25 mm ID × 0.10 μm df with a poly(5% diphenyl/95% dimethyl siloxane) stationary phase. The mass spectrometry ionization of the silylated derivatives was performed under milder EI conditions (20-eV energy) that, respect to common 70-eV energy, generated scan mass spectra with higher relative and absolute intensities of high-mass diagnostic ions, along with a reduced abundance of the low-mass. The signals of the ionized compounds were acquired in multi-reaction-monitoring (MRM) mode, thus enabling the obtainment of highly-sensitive and selective quantitative data. The developed method was validated in term of linearity, accuracy, limits of detection (LoD) and quantification (LoQ). In detail, regression coefficients of the calibration curves were between 0.9959 and 0.9999; LoDs ranged from 0.06 ng mL−1 to 0.73 ng mL−1 and LoQs from 0.16 ng mL−1 to 2.45 ng mL−1. With respect to accuracy, the serum SRM 972a certified reference material (Vitamin D metabolites in frozen human serum) (Levels 1–4) was analyzed.

An analytical expression for temperature-dependent infrared intensities in fully coupled anharmonic molecular systems

We present the analytical expression for determining the temperature evolution of absolute integrated infrared (IR) intensities of fundamental bands in fully coupled anharmonic molecular systems. Only harmonic frequencies and integrated IR intensities (within the double harmonic approximation) are needed to predict the absolute temperature-dependent IR intensities of the fundamental bands. These quantities can be readily obtained from ab initio electronic structure calculations for relatively large molecules. In order to illustrate the accuracy of the expression we compare the results from this formula using harmonic frequencies and intensities from a tight-binding potential energy surface with the results from semiclassically prepared molecular dynamics (SCP-MD) simulations on the same potential energy surface for the naphthalene molecule. For a favorable comparison with experimental data we use the same analytical expression with the more accurate B3LYP/cc-pVDZ harmonic frequencies and intensities. We conclude that the IR intensity changes that our proposed formula predicts in the fundamental vibrational bands are mainly due to intramolecular vibrational energy redistribution (IVR).

Ratiometric mechanoluminescence in single Pr3+ activated LiGa5 O8.

Mechanoluminescence (ML) materials have potential applications in information storage, anti-counterfeiting, and stress sensing. Conventional stress sensing based on absolute ML intensity is prone to significant mistakes owing to the unpredictability of measurement surroundings. However, implementing a ratiometric ML sensing technique may considerably ameliorate this issue. In this study, a single activator doped gallate material (LiGa5 O8 :Pr3+ ) is proposed to determine the relationship between the ML intensity and the change in local positional symmetry that occurs when the material is subjected to stress. The sensing reliability of the ML intensity ratio under different factors (Force; Content; Thickness; Materials) is systematically analyzed, where the factor that has the greatest effect on the proportional ML is the concentration, with the ML intensity asymmetry ratio decreasing from 1.868 to 1.30 varying concentration at constant stress. The color-resolved visualization of stress sensing is further realized, which opens a new path for a ratiometric ML-based strategy to improve the reliability of stress sensing.