Standard Flash Research Articles

Thermodynamic and economic analysis of a solar-assisted ejector-enhanced flash tank vapor injection heat pump cycle with dual evaporators

This paper proposes a solar-assisted ejector-enhanced flash tank vapor injection heat pump cycle with dual evaporators (SEFVIC), designed for heat pump drying application. Compared to the standard flash tank vapor injection heat pump cycle (FVIC), the SEFVIC uses an additional high-temperature evaporator to further minimize irreversible losses during the heat transfer process. Moreover, it integrates solar energy to improve the drying quality and heating capacity of the cycle. Meanwhile, the introduction of an ejector improves the system's performance by reducing throttling loss. The advantages of SEFVIC over FVIC are evaluated using theoretical models based on the first and second laws of thermodynamics. Results show that SEFVIC reveals a 34.1 % improvement in the heating coefficient of performance and a 192.8 % enhancement in volumetric heating capacity compared to FVIC under typical operating condition. Notably, SEFVIC maintains superior performance even at lower evaporating temperatures. Moreover, exergy research indicates that 77.1 % of the total exergy destruction in SEFVIC is attributed to the solar collector. Economic analysis indicates that the integration of solar energy into the SEFVIC is economically beneficial. These findings highlight the prospective application of SEFVIC and guide combining the multi-temperature heat pump drying system and auxiliary solar source.

Ultra-High Dose Rate Helium Ion Beams: First In Vivo Evidence for Neuroprotective FLASH Effect.

To investigate ultra-high-dose rate helium ion irradiation and its potential FLASH sparing effect with the endpoint acute brain injury in preclinical in vivo settings. Raster-scanned helium ion beams were administered to explore and compare the impact of dose rate variations between standard dose rate (SDR at 0.2 Gy/s) and FLASH (at 141 Gy/s) radiotherapy (RT). Irradiation-induced brain injury was investigated in healthy C57BL/6 mice via DNA damage response kinetic studies using nuclear γH2AX as a surrogate for double-strand breaks (DSB). The integrity of the neurovascular and immune compartments was assessed via CD31+ microvascular density and microglia/macrophages activation. Iba1+ ramified and CD68+ phagocytic microglia/macrophages were quantified, together with the expression of inducible nitric oxide synthetase (iNOS). Helium FLASH RT significantly prevented acute brain tissue injury compared with SDR. This was demonstrated by reduced levels of DSB and structural preservation of the neurovascular endothelium after FLASH RT. Moreover, FLASH RT exhibited reduced activation of neuroinflammatory signals compared with SDR, as detected by quantification of CD68+ iNOS+ microglia/macrophages. To our knowledge, this is the first report on the FLASH-sparing neuroprotective effect of raster scanning helium ion radiotherapy in vivo.

Prediction of the influence of pressure on flash points of liquid fuels at sub-atmospheric pressure

Aircraft fuel tanks experience sub-atmospheric pressure during flight, and so do fuels during storage and transportation at high altitudes. Additionally, chemical processes commonly operate at non-atmospheric pressure. Flash points measured at sub-atmospheric pressure are lower than those measured at the standard atmospheric pressure of 101.3 kPa, signifying that ignitable liquids at sub-atmospheric pressure are more hazardous than those at 101.3 kPa. This study developed a model for predicting the influence of pressure on flash points on the basis of basic thermodynamic characteristics; this model was validated against experimental data obtained from the literature for six single-component and multiple-component liquid fuels at sub-atmospheric pressure. The proposed model effectively predicts closed-cup flash points, with small deviations in the range 0.18 °C–1.25 °C. However, because the model's assumption of vapor–liquid equilibrium was violated in the experiments, the predicted open-cup flash points did not agree well with their experimental counterparts, with the deviations in the range 1.11 °C–12.55 °C. Nevertheless, the trends predicted by the model agreed with those in the experimental data. Furthermore, standard flash point test method (such as ASTM D56-22, ASTMD93-20, and ASTMD7094-17) are based on a linear formula for correcting flash points measured at pressures other than 101.3 kPa. When the ambient pressure is approximately 101.3 kPa during flash point testing, the slope value of the correction formula should be changed from 0.25 to 0.20.

ERG Responses in Albinism, Idiopathic Infantile Nystagmus, and Controls.

Our primary aim was to compare adult full-field ERG (ffERG) responses in albinism, idiopathic infantile nystagmus (IIN), and controls. A secondary aim was to investigate the effect of within-subject changes in nystagmus eye movements on ffERG responses. Dilated Ganzfeld flash ffERG responses were recorded using DTL electrodes under conditions of dark (standard and dim flash) and light adaptation in 68 participants with albinism, 43 with IIN, and 24 controls. For the primary aim, the effect of group and age on ffERG responses was investigated. For the secondary aim, null region characteristics were determined using eye movements recorded prior to ffERG recordings. ffERG responses were recorded near and away from the null regions of 18 participants also measuring the success rate of recordings. For the primary aim, age-adjusted photopic a- and b-wave amplitudes were consistently smaller in IIN compared with controls (P < 0.0001), with responses in both groups decreasing with age. In contrast, photopic a-wave amplitudes increased with age in albinism (P = 0.0035). For the secondary aim, more intense nystagmus significantly reduced the success rate of measurable responses. Within-subject changes in nystagmus intensity generated small, borderline significant differences in photopic b-wave peak times and a-and b-wave amplitudes under scotopic conditions with standard flash. Age-adjusted photopic ffERG responses are significantly reduced in IIN adding to the growing body of evidence of retinal abnormalities in IIN. Differences between photopic responses in albinism and controls depend on age. Success at obtaining ffERG responses could be improved by recording responses at the null region.

Production and Characterization of Ackee Apple (Blighia sapida) Seeds and African Star Apple (Chrysophyllum albidum) Seeds Oil Mixtures and their Biodiesel

This paper focused on the characterization of oils and biodiesels derived from Ackee apple seeds and African star apple seeds obtained from local markets. The oils from individual seeds and their mixtures at varying ratios were characterised for relative density, free fatty acid, acid, iodine, and saponification, which yielded 0.91 g/cm3, 1.06 mg-KOH/g, 2.12 mg-KOH/g, 38.36mg-iodine/100g, and 195.74 mg-KOH/g of ackee seed oil, respectively. And 0.89 g/cm3, 2.105 mg-KOH/g, 4.2 mg-KOH/g, 52.49 mg-iodine/100 g, and 227.7 mg-KOH/g of African star apple seed oil, respectively. The highest relative density of 0.9064 g/cm3 and free fatty acid of 3.73 mg-KOH/g were achieved from the mixture of ackee apple and African star apple seeds’ oils at 80 and 20%, respectively, while the highest saponification of 221.264 mg-KOH/g and iodine of 49.66 mg-iodine/100 g were obtained from the oil mixture of 20 and 80%, respectively. Also, the oils extracted from the seeds, were subjected to a transesterification process to produce biodiesel. 144°C flash point, 206°C fire point, and 2.8°C cloud point were obtained from the biodiesel of the oil mixture of 20 and 80%, respectively. Further analysis of the mixtures showed low volatility and high resistance to fire due to their high flash and fire points. The highest value recorded for the flash point is lower when compared with some other seed oils flash points; however this value is higher than the standard flash point for biodiesels .Highest boiling point of 64°C was attained at an oil mixture ratio of 60 and 40%, respectively. This value is too low compared to the normal boiling point range of 315-350°C for biodiesels, and the high acid values recoded for the mixtures make the oils inedible. The oils, however, have advantages over other edible seed oils as they will serve as valuable ingredients in the soap-making industries since they are not competing with food resources

Paediatric norms for photopic electroretinogram testing based on a large cohort of Chinese preschool children

ObjectiveFull-field electroretinogram (ffERG) is an objective test to determine the electroretinal activities in response to light stimulation for investigating retinal physiology and diagnosing retinal diseases. This study aimed to establish...

Streamlined synthetic assembly of α-chiral CAAC ligands and catalytic performance of their copper and ruthenium complexes.

The unique electronic and steric parameters of chiral cyclic alkyl amino carbene (CAAC) ligands render them appealing steering ligands for enantioselective transition-metal catalyzed transformations. Due to the lack of efficient synthetic strategies to access particularly attractive α-chiral CAACs assessment and exploitation of their full synthetic potential remain difficult. Herein, we report a streamlined strategy to assemble a library of diastereo- and enantiomerically pure CAAC ligands featuring the notoriously difficult to access α-quaternary stereogenic centers. A tailored Julia-Kocienski olefination reagent allows the Claisen-rearrangement to be leveraged as an expedient route to form the synthetically pivotal racemic α-chiral methallyl aldehydes. Subsequent condensation with chiral amines and further cyclization provided a library of diastereomeric mixtures of the targeted ligand precursors. The CAAC salts as well as their corresponding metal complexes are conveniently separable by standard silica gel flash chromatography closing a long-standing accessibility gap in chiral CAAC ligands with proximal α-chirality. The rapid availability of both diastereomers enables testing of the relevance and synergistic effects of two chiral centers on the ligand in catalytic applications. A broad range of metal complexes with copper, gold, rhodium and ruthenium were obtained and structurally analyzed. The catalytic performances of the corresponding chiral CAAC copper and ruthenium complexes were assessed in enantioselective conjugate borylations and asymmetric ring closing metathesis, displaying selectivities of up 95 : 5 er.

Update on the range of visual electrophysiology tests and heir application with clinical examples

The International Society for clinical electrophysiology of vision (ISCEV) publishes open‐access standards and guidelines for routine electrophysiological tests of the visual system in order to optimize diagnostic value, to promote consistency and to allow meaningful inter‐laboratory comparisons. The ISCEV also publishes extended protocols with the aim of promoting convergence of methods that are not yet standardized, for tests that are widely used but often performed as an addition to the minimum ISCEV standard procedures (see www.ISCEV.org for all publications).This talk will outline the main ISCEV standard methods including the full‐field electroretinogram (ERG), pattern ERG (PERG) and multifocal ERG (mfERG). Several extended full‐field ERG protocols will also be highlighted, including the dark‐adapted (DA) red flash ERG, photopic On–Off ERG and S‐cone ERG. The use of these methods in the clinic will be illustrated in cases of inherited and acquired retinal disorders, to show how the extended protocols complement standard techniques, to aid diagnosis and patient management and to probe and detail retinal function phenotypes.The Standard full‐field ERG is recorded under dark‐adapted (DA) and light‐adapted (LA) conditions and provides a measure of generalized rod and cone system function at the level of the outer and inner retina, with minimal contribution from the macula. The mfERG assesses cone system function across the posterior pole and the PERG assesses macular and macular retinal ganglion cell function.The DA red flash ERG is an extended protocol that provides a measure of generalized dark‐adapted retinal function, with the advantage of having both a cone system x‐wave and a rod system b‐wave within the same waveform. This enables the relative involvement of rod and cone systems to be assessed simultaneously and can help determine the origins of severely attenuated standard DA strong flash ERGs. The DA red flash ERG is also useful for assessing cone system function in photophobic patients, and in patients with variable ability to comply with longer ERG protocols. The photopic On–Off ERG is a response to an extended light stimulus (duration 150 or 200 ms) and is used to assess generalized cone system function of both the On and Off retinal pathways, useful when there is a locus of dysfunction that is post‐phototransduction or post‐receptoral, when On and Off retinal systems may be similarly, selectively or specifically affected e.g., in different forms of congenital stationary night blindness (CSNB) or in forms of toxic retinopathy. The S‐cone ERG (short‐wavelength or “blue” flash ERG) is used to probe the function of the S‐cone retinal pathway, and can aid diagnosis and characterization in a variety of retinal dystrophies and disorders e.g., distinguishing between achromatopsia and S‐cone monochromacy.

Development of "DiabetesSutra" a mobile application for lifestyle management of Type 2 Diabetes in India.

Multiple mhealth (mobile health) interventions and mobile applications have been developed to support diabetes self-management. However, most of the apps are developed without the need for assessment and evaluation by experts in the field. This study aimed to design and develop a mobile application (app) supporting diabetes self-management for people with Type 2 Diabetes Mellitus (T2D) using a systematic approach. In this study mixed method design was used to develop the mobile application. The mhealth intervention was designed and developed in five steps: i) Extensive literature search, ii) Needs assessment of patients with T2D with the help of healthcare providers and patients (Interviews with 15 healthcare providers like clinicians, dietitians, and diabetes educators, and 2 focus group discussions with patients) iii) Ideation and content development of app based on outcomes of needs assessment; iv) content validation (by 10 healthcare providers) and v) App development on a hybrid platform. Evaluation of the app by users i.e., type 2 diabetes patients was done using the users' Mobile App rating scale (uMARS). The app was evaluated by 40 patients and rated on the uMARS questionnaire. A patient-centric mobile app was developed for the nutritional management of diabetes with three modules: The patient module, the Evaluation module, and the Healthcare provider module. The patient module was the app that was provided to the patients with features like diet, physical activity, blood glucose log, education, etc., in addition to, a symptom checker, Stress meter blog, and FAQ. The evaluation module was integrated with the app it works when a user enters any log, it evaluates the entry against the standard cutoffs and flash prompts on the screen. The Healthcare provider module interacts with the server to provide them with patient data, comments, and feedback. The users found the app to be satisfactory. Incorporating additional features to enhance the user interface and streamline navigation could potentially enhance user engagement, thereby aiding in the management of T2D.

Cone-driven strong flash electroretinograms in healthy adults: Prevalence of negative waveforms

PurposeBoth rod and cone-driven signals contribute to the electroretinogram (ERG) elicited by a standard strong flash in the dark. Negative ERGs usually reflect inner retinal dysfunction. However, in diseases where rod photoreceptor function is selectively lost, a negative waveform might represent the response of the dark-adapted cone system. To investigate the dark-adapted cone-driven waveform in healthy individuals, we delivered flashes on a dim blue background, designed to saturate the rods, but minimally adapt the cones.MethodsERGs were recorded, using conductive fibre electrodes, in adults from the TwinsUK cohort. Responses to 13 cd m−2 s white xenon flashes (similar to the standard DA 10 flash), delivered on a blue background, were analysed. Photopic and scotopic strengths of the background were 1.3 and 30 cd m−2, respectively; through a dilated pupil, this is expected to largely saturate the rods, but adapt the cones much less than the standard ISCEV background. ResultsMean (SD) participant age was 62.5 (11.3) years (93% female). ERGs from 203 right and 204 left eyes were included, with mean (SD) b/a ratios of 1.22 (0.28) and 1.18 (0.28), respectively (medians, 1.19 and 1.17). Proportions with negative waveforms were 23 and 26%, respectively. Right and left eye b/a ratios were strongly correlated (correlation coefficient 0.74, p < 0.0001). We found no significant correlation of b/a ratio with age.ConclusionsOver 20% of eyes showed b/a ratios less than 1, consistent with the notion that dark-adapted cone-driven responses to standard bright flashes can have negative waveforms. The majority had ratios greater than 1. Thus, whilst selective loss of rod function can yield a negative waveform (with reduced a-wave) in some, our findings also suggest that loss of rod function can occur without necessarily yielding a negative ERG. One potential limitation is possible mild cone system adaptation by the background.

Utility of Light-Adapted Full-Field Electroretinogram ON and OFF Responses for Detecting Glaucomatous Functional Damage.

To compare parameters of electroretinogram (ERG) responses for their ability to detect functional loss in early stages of nonhuman primate (NHP) experimental glaucoma (EG), including photopic negative responses (PhNR) to a standard brief red flash on a blue background (R/B) and 200-ms-long R/B and white-on-white (W/W) flashes, to W/W flicker stimuli (5-50Hz), and to a dark-adapted intensity series. Light-adapted ERGs were recorded in 12 anesthetized monkeys with unilateral EG. Amplitudes and implicit times of the a-wave, b-wave, and d-wave were measured, as well as amplitudes of PhNRs and oscillatory potentials for flash onset and offset. Flicker ERGs were measured using peak-trough and fundamental frequency analyses. Dark-adapted ERG parameters were modeled by Naka-Rushton relationships. Only PhNR amplitudes were significantly reduced in EG eyes compared to fellow control (FC) eyes. The d-wave implicit time was delayed in EG versus FC eyes only for the W/W long flash, but in all eyes it was 10 to 20 ms slower for R/B versus the W/W condition. Flicker ERGs were <0.5 ms delayed in EG versus FC overall, but amplitudes were affected only at 5Hz. The brief R/B PhNR amplitude had the highest sensitivity to detect EG and strongest correlation to parameters of structural damage. The PhNR to the standard brief R/B stimulus was best for detecting and following early-stage functional loss in NHP EG. These results suggest that there would be no benefit in using longer duration flashes to separate onset and offset responses for clinical management of glaucoma.

Simulation of a Fully Digital Computing-in-Memory for Non-Volatile Memory for Artificial Intelligence Edge Applications.

In recent years, digital computing in memory (CIM) has been an efficient and high-performance solution in artificial intelligence (AI) edge inference. Nevertheless, digital CIM based on non-volatile memory (NVM) is less discussed for the sophisticated intrinsic physical and electrical behavior of non-volatile devices. In this paper, we propose a fully digital non-volatile CIM (DNV-CIM) macro with compressed coding look-up table (LUT) multiplier (CCLUTM) using the 40 nm technology, which is highly compatible with the standard commodity NOR Flash memory. We also provide a continuous accumulation scheme for machine learning applications. When applied to a modified ResNet18 network trained under the CIFAR-10 dataset, the simulations indicate that the proposed CCLUTM-based DNV-CIM can achieve a peak energy efficiency of 75.18 TOPS/W with 4-bit multiplication and accumulation (MAC) operations.

Systemic Reduction of Glut1 Normalizes Retinal Dysfunction, Inflammation, and Oxidative Stress in the Retina of Spontaneous Type 2 Diabetic Mice

Defects in the light-evoked responses of the retina occur early in the sequalae of diabetic retinopathy (DR). These defects, identified through the electroretinogram (ERG), represent dysfunction of retinal neurons and the retinal pigment epithelium and are commonly identifiable at the timing of, or almost immediately following, diabetes diagnosis. Recently, systemic reduction of the facilitated glucose transporter type 1, Glut1, in type 1 diabetic mice was shown to reduce retinal sorbitol accumulation, mitigate ERG defects, and prevent retinal oxidative stress and inflammation. Herein, the study investigated whether systemic reduction of Glut1 also diminished hallmarks of DR in type 2 diabetic mice. Transgenic nondiabetic Leprdb/+ and spontaneously diabetic Leprdb/db mice that expressed wild-type (Glut1+/+) or systemically reduced levels of Glut1 (Glut1+/-) were aged and subjected to standard strobe flash electroretinography and c-wave analysis before evaluation of inflammatory cytokines and oxidative stress molecules. Although Leprdb/dbGlut1+/- mice still displayed overt obesity and diabetes, no scotopic, photopic, or c-wave ERG defects were present through 16 weeks of age, and expression of inflammatory cytokines and oxidative stress molecules was also normalized. These findings suggest that systemic reduction of Glut1 is sufficient to prevent functional retinal pathophysiology in type 2 diabetes. Targeted, moderate reductions of Glut1 or inhibition of Glut1 activity in the retina of diabetic patients should be considered as a novel therapeutic strategy to prevent development and progression of DR.

Digital Photography versus Spectrophotometry Assessment ofColor Stability of Resin Composite

Purpose: To compare digital photography to spectrophotometry in evaluating the color stability of resin composite. Materials and methods: Thirty- two disc-like specimens of Filtek Z350 resin composite were prepared and color-assessed; before and after 30 days of submersion in coffee solution. For each specimen, color was assessed according to Commission Internationale de I’Eclairage (CIE) color space values using: Two different versions of Canon Digital Single Lens Reflex (DSLR) camera; with standard lenses, flash, and settings: Canon 600d (Group I) and Canon 1100d (Group II), and a digital spectrophotometer (Vita Easyshade advance 4.0; Vita Zahnfabrik, Bad Sackingen, Germany) as a control (group lll). Color change (ΔE) was recorded for individual devices, tabulated, and statistically analyzed using oneway ANOVA, then Tukey’s post hoc test (P ≤ 0.05). Results: Statistically, no significant difference appeared among the used devices (P≤ 0.05) while assessing the color stability of Filtek Z350 resin composite. Conclusions: Both devices are similarly valuable for color assessment of resin composite.

Application of Ferromagnetic Microwires as Temperature Sensors in Measurements of Thermal Conductivity

A method for the determination of the thermal conductivity of polymer composite materials by using Co-based ferromagnetic microwires is proposed. Microwire segments were integrated into the samples of studied materials during their manufacture and used as current microheaters and resistance thermometers. As a representative material, we used a material based on nitrile butadiene rubber filled with hexagonal boron nitride after its low-temperature carbonization and a significant increase in thermal conductivity. The thermal conductivity values of composite samples determined during experiments varied from 1.0 W/(m·K) to 1.8 W/(m·K) depending on the percentage of boron nitride. The thermal conductivity values obtained are in good agreement with the estimates obtained by the standard laser flash method.

Age and Sex-Related Changes in Retinal Function in the Vervet Monkey.

Among the deficits in visual processing that accompany healthy aging, the earliest originate in the retina. Moreover, sex-related differences in retinal function have been increasingly recognized. To better understand the dynamics of the retinal aging trajectory, we used the light-adapted flicker electroretinogram (ERG) to functionally assess the state of the neuroretina in a large cohort of age- and sex-matched vervet monkeys (N = 35), aged 9 to 28 years old, with no signs of obvious ocular pathology. We primarily isolated the cone–bipolar axis by stimulating the retina with a standard intensity light flash (2.57 cd/s/m2) at eight different frequencies, ranging from 5 to 40 Hz. Sex-specific changes in the voltage and temporal characteristics of the flicker waveform were found in older individuals (21–28 years-old, N = 16), when compared to younger monkeys (9–20 years-old, N = 19), across all stimulus frequencies tested. Specifically, significantly prolonged implicit times were observed in older monkeys (p < 0.05), but a significant reduction of the amplitude of the response was only found in old male monkeys (p < 0.05). These changes might reflect ongoing degenerative processes targeting the retinal circuitry and the cone subsystem in particular. Altogether, our findings corroborate the existing literature in humans and other species, where aging detrimentally affects photopic retinal responses, and draw attention to the potential contribution of different hormonal environments.

Effectiveness of adding alarms to flash glucose monitoring in adults with type 1 diabetes under routine care

AimWhether glucose sensor alarms improve metabolic control and are accepted by individuals with diabetes is unclear. Here, we investigated whether switching from a standard flash glucose monitoring system (FGM1) to a system equipped with hypo- and hyperglycemia alarms (FGM2) improves glycemic control and psychological outcomes in adults with type 1 diabetes (T1D).MethodsSubjects with T1D and > 4% of time in hypoglycemia or > 40% of time in hyperglycemia were studied while wearing FGM1 (4 weeks) and after switching to FGM2 for 8 weeks. The primary endpoint was the change in time in range (TIR 70–180 mg/dl [3.9–10.0 mmol/L]) after 4 weeks of FGM2 use. Time below range (TBR), time above range (TAR), mean glucose, coefficient of variation (CV), sensor scans, treatment satisfaction, and hypoglycemia fear were secondary outcomes.ResultsWe included 38 subjects aged 33.7 ± 12.6 year. During 4 weeks of FGM2 use, TIR increased from 52.8 to 57.0% (p = 0.001), TBR decreased from 6.2 to 3.4% (p < 0.0001) as did time < 54 mg/dl (from 1.4 to 0.3%, p < 0.0001) and CV (from 39.6% to 36.1%, p < 0.0001). These changes were confirmed after 8 weeks of FGM2 use. Treatment satisfaction improved and fear of hypoglycemia decreased.Subjects who had > 4% of time in hypoglycemia at baseline showed the greatest improvements in glucose control and treatment satisfaction.ConclusionSwitching from FGM1 to FGM2 improved TIR and treatment satisfaction and reduced fear of hypoglycemia. Participants who benefited most from switching from FGM1 to FGM2 were those prone to hypoglycemia.

Quantifying the DNA-damaging Effects of FLASH Irradiation With Plasmid DNA

To investigate a plasmid DNA nicking assay approach for isolating and quantifying the DNA-damaging effects of ultrahigh-dose-rate (ie, FLASH) irradiation relative to conventional dose-rate irradiation. We constructed and irradiated phantoms containing plasmid DNA to nominal doses of 20 Gy and 30 Gy using 16 MeV electrons at conventional (0.167 Gy/s) and FLASH (46.6 Gy/s and 93.2 Gy/s) dose rates. We delivered conventional dose rates using a standard clinical Varian iX linear accelerator and FLASH dose rates (FDRs) using a modified Varian 21EX C-series linear accelerator. We ran the irradiated DNA and controls (0 Gy) through an agarose gel electrophoresis procedure that sorted and localized the DNA into bands associated with single strand breaks (SSBs), double strand breaks (DSBs), and undamaged DNA. We quantitatively analyzed the gel images to compute the relative yields of SSBs and DSBs and applied a mathematical model of plasmid DNA damage as a function of dose to compute the relative biological effectiveness (RBE) of SSB and DSB (RBESSB and RBEDSB) damage for a given endpoint and FDR. Both RBESSB and RBEDSB were less than unity with the FDR irradiations, indicating FLASH sparing. With regard to the more deleterious DNA DSB damage, the DSB RBEs of FLASH beams at dose rates of 46.6 Gy/s and 93.2 Gy/s relative to the conventional 16 MeV beam dose rate were 0.54 ± 0.15 and 0.55 ± 0.17, respectively. This study demonstrated the feasibility of using a DNA-based phantom to isolate and assess the FLASH sparing effect on DNA. We also found that FLASH irradiation causes less damage to DNA compared with a conventional dose rate. This result supports the notion that the protective effect of FLASH irradiation occurs at least partially via fundamental biochemical processes.

Intent to Change Sun-Protective Behaviors Among Hispanic People After a UV Photoaging Intervention: Cohort Study.

Mortality rates from melanoma are higher among Hispanic populations than non-Hispanic White (NHW) populations. Interventions to improve sun safety are needed. The Reveal Imager is a camera that uses standard cross-polarized flash photography to record surface and subsurface skin conditions. This study aims to determine the intervention's effectiveness in increasing awareness of sun damage and exposure reduction between Hispanic and NHW populations. A cohort of 322 participants, aged ≥18 years, were recruited from community events in 2018. Baseline information was collected on demographics, sun exposure, and perception of risk factors. A facial image was then captured using the Reveal Imager. The results were explained and counseling on sun safety was given, followed by filling out an immediate postimage survey. Chi-square tests, analysis of variance, Wilcoxon signed-rank test, McNemar tests, and multivariable logistic regression were used. At follow-up, 125 of 141 (89%) Hispanic participants reported that viewing the UV photoaged image influenced intent-to-change sun protection behaviors, compared to 88 of 121 (73%) NHW participants (odds ratio 2.9, 95% CI 1.5-5.6). Of 141 Hispanic participants, 96 (68%) reported that they intended to increase sunscreen use, compared to only 41 of 121 (34%) NHW participants (P<.001). We demonstrated an application of Reveal Imager for education and risk assessment. The Reveal Imager was especially helpful in motivating intention to change sun exposure among Hispanic populations.

Prevalence of electronegative electroretinograms in a healthy adult cohort

ObjectiveAn electronegative electroretinogram (ERG) can indicate important ocular or systemic disease. This study explored the prevalence of electronegative responses to dark-adapted stimuli in a largely healthy cohort.Methods and Analysis211 participants...