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1.
Small Methods ; : e2400460, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39248667

RESUMEN

"Flash heating" that transiently generates high temperatures above 1000 °C has great potential in synthesizing new materials with unprecedently properties. Up to now, the realization of "flash heating" still relies on the external power, which requires sophisticated setups for vast energy input. In this study, a mechanochemically triggered, self-powered flash heating approach is proposed by harnessing the enthalpy from chemical reactions themselves. Through a model reaction between Mg3N2/carbon and P2O5, it is demonstrated that this self-powered flash heating is controllable and compatible with conventional devices. Benefit from the self-powered flash heating, the resulting product has a nanoporous structure with a uniform distribution of phosphorus (P) nanoparticles in carbon (C) nanobowls with strong P─-C bonds. Consequently, the P/C composite demonstrates remarkable energy storage performance in lithium-ion batteries, including high capacity (1417 mAh g-1 at 0.2 A g-1), robust cyclic stability (935 mAh g-1 at 2 A g-1 after 800 cycles, 91.6% retention), high-rate capability (739 mAh g-1 at 20 A g-1), high loading performance (3.6 mAh cm-2 after 100 cycles), and full cell cyclic stability (90% retention after 100 cycles). This work broadens the flash heating concept and can potentially find application in various fields.

2.
Artículo en Inglés | MEDLINE | ID: mdl-39258770

RESUMEN

Objective: This meta-analysis aimed to compare the effect of the real-time continuous glucose monitoring (rt-CGM) and flash glucose monitoring (FGM) on glycemic control in adults with type 1 diabetes mellitus (T1DM). Methods: A systematic literature search of all relevant studies comparing the clinical effectiveness of rt-CGM and FGM in adults with T1DM on Cochrane Library, PubMed, Embase, Web of Science, and Scopus from January 2015 to June 2023 was performed. The primary endpoints were glycated hemoglobin (HbA1c) and TIR (time in range). Secondary endpoints included time below range [TBR (<3.9 mmol/L) and (<3.0 mmol/L)], time above range [TAR (>10.0 mmol/L) and (>13.9 mmol/L)], mean glucose, and glycemic variability (GV) [standard deviations (SD) and coefficient of variation (CV)]. Results: Six studies with 1516 TIDM patients, including three randomized controlled trials and three observational studies, were enrolled in this meta-analysis. Compared to FGM, rt-CGM led to greater glycemic control, represented by higher TIR (%, 3.9 ∼ 10 mmol/L) (SMD = 0.59, 95%CI: 0.37 ∼ 0.81, p < 0.001), decreased TBR (%, <3.9 mmol/L) (SMD = -1.45, 95%CI: -2.33 ∼ -0.57, p = 0.001), decreased TAR [(%, >10.0 mmol/L) (SMD = -0.38, 95%CI: -0.71 ∼ -0.04, p = 0.03) and (%, >13.9 mmol/L) (SMD = -0.42, 95%CI: -0.79 ∼ -0.04, p = 0.03), respectively], lower mean glucose (SMD = -0.18, 95%CI: -0.31 ∼ -0.06, p = 0.003), decreased SD (SMD = -0.70, 95%CI: -1.09 ∼ -0.31, p < 0.001), and decreased CV (SMD = -0.76, 95%CI: -1.05 ∼ -0.47, p < 0.001). However, there was no difference in lowering HbA1c and TBR (%, <3.0 mmol/L) between groups. Conclusion: The rt-CGM outperformed FGM in improving several key CGM metrics among adults with T1DM, but there is no significant difference in HbA1c and TBR (<3.0 mmol/L).

3.
Intern Med J ; 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39230209

RESUMEN

The use of glucose sensors to triage post-discharge follow-up was investigated among hospital inpatients with type 2 diabetes. Feasibility, utility and patient satisfaction with this model of care were studied. Feasibility was 36.5%, with 90/198 (45.5%) inpatients discharged with glucose sensors but 9.0% unable to use glucose sensors effectively. Follow-up plans were altered in 76.3% of the patients able to use the sensor technology. Patient satisfaction was high and was improved on follow-up after 6 months.

4.
Cancer Radiother ; 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39304401

RESUMEN

Ultra-high dose rate external beam radiotherapy (UHDR-RT) uses dose rates of several tens to thousands of Gy/s, compared with the dose rate of the order of a few Gy/min for conventional radiotherapy techniques, currently used in clinical practice. The use of such dose rate is likely to improve the therapeutic index by obtaining a radiobiological effect, known as the "FLASH" effect. This would maintain tumor control while enhancing tissues protection. To date, this effect has been achieved using beams of electrons, photons, protons, and heavy ions. However, the conditions required to achieve this "FLASH" effect are not well defined, and raise several questions, particularly with regard to the definition of the prescription, including dose fractionation, irradiated volume and the temporal structure of the pulsed beam. In addition, the dose delivered over a very short period induces technical challenges, particularly in terms of detectors, which must be mastered to guarantee safe clinical implementation. IRSN has carried out an in-depth literature review of the UHDR-RT technique, covering various aspects relating to patient radiation protection: the radiobiological mechanisms associated with the FLASH effect, the used temporal structure of the UHDR beams, accelerators and dose control, the properties of detectors to be used with UHDR beams, planning, clinical implementation, and clinical studies already carried out or in progress.

5.
Int J Biol Macromol ; 280(Pt 2): 135781, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39304046

RESUMEN

Pesticides are vital for ensuring crop protection and stable yields, but their low efficiency and eco-unfriendly carriers raise environmental concerns. In this study, abamectin nanopesticides were designed and fabricated using natural polysaccharides [gum arabic (GA)] and a co-stabiliser via flash nanoprecipitation (FNP) method to reduce the size of nanopesticides and enhance their foliar affinity and deposition. Various co-stabilisers were innovatively introduced into the FNP process; the synergy between GA and the co-stabiliser significantly reduced the particle size (111.5 nm), narrowed the size distribution (polydispersity index = 0.078), and enhanced the stability and release performance of the nanopesticides. Importantly, the downsized nanopesticides effectively improved retention on leaf surfaces, reducing pesticide loss. In addition, because of the excellent control capability of the FNP method, the particle size of the nanopesticides could be flexibly adjusted by modifying the flow-based process parameters. Nanopesticides with small sizes demonstrated good control efficacy against Tetranychus urticae, comparable to those of commercial emulsion in water formulations. This study provides an effective approach for enhancing the utilisation efficiency of pesticide droplets by reducing particle size to ensure sustainable agriculture.

6.
Psychol Sci ; 35(9): 1035-1047, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39222160

RESUMEN

Statistical learning is a powerful mechanism that enables the rapid extraction of regularities from sensory inputs. Although numerous studies have established that statistical learning serves a wide range of cognitive functions, it remains unknown whether statistical learning impacts conscious access. To address this question, we applied multiple paradigms in a series of experiments (N = 153 adults): Two reaction-time-based breaking continuous flash suppression (b-CFS) experiments showed that probable objects break through suppression faster than improbable objects. A preregistered accuracy-based b-CFS experiment showed higher localization accuracy for suppressed probable (versus improbable) objects under identical presentation durations, thereby excluding the possibility of processing differences emerging after conscious access (e.g., criterion shifts). Consistent with these findings, a supplemental visual-masking experiment reaffirmed higher localization sensitivity to probable objects over improbable objects. Together, these findings demonstrate that statistical learning alters the competition for scarce conscious resources, thereby potentially contributing to established effects of statistical learning on higher-level cognitive processes that require consciousness.


Asunto(s)
Concienciación , Tiempo de Reacción , Humanos , Concienciación/fisiología , Adulto , Masculino , Femenino , Adulto Joven , Tiempo de Reacción/fisiología , Aprendizaje/fisiología , Estado de Conciencia/fisiología , Percepción Visual/fisiología , Adolescente
7.
Ann Med ; 56(1): 2397573, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39233610

RESUMEN

PURPOSE: To evaluate the findings and the correlation of optical coherence tomography angiography and pattern and flash electroretinography in diabetes mellitus without retinopathy. METHODS: Seventy-six eyes of 38 diabetic patients and age- and gender-matched control subjects were included in the study. The foveal avascular zone (FAZ), whole, foveal, parafoveal and perifoveal vascular densities of the superficial capillary plexus (SCP), deep capillary plexus (DCP) and choriocapillary plexus (CCP) layers were analyzed using optical coherence tomography angiography (OCTA). The amplitudes and implicit times of P50 and N95 waves of the pattern ERG (pERG) and the amplitudes and implicit times of the scotopic and photopic b-waves and oscillatory potentials (OP) of the flash ERG (fERG) tests were evaluated using the Metrovision brand monpack model device. RESULTS: The mean age of the patients was 59.7 ± 7.9 [range 43-79] years. Eighteen (47%) of the patients were female and 20 (53%) were male. The mean duration of diabetes was 7.45 ± 6.2 [range 1-20] years. No significant difference in FAZ area was found between study subjects and controls. Vascular density (VD) values of the superficial capillary plexus (SCP) layer were significantly lower (whole VD, 44.7 ± 3.3 vs. 46.6 ± 3.2%, p = 0.01, foveal VD 16.8 ± 6.4 vs. 24.9 ± 6.1%, p < 0.01, parafoveal VD 45.6 ± 4.5 vs. 47.1 ± 4.4%, p = 0.27 and perifoveal VD 45.5 ± 3.3 vs. 47.3 ± 3.1%, p = 0.01, respectively) in the diabetic group except the parafoveal area. VD measurements in deep and choriocapillary plexuses did not significantly differ between the groups (p > 0.05). ERG tests revealed significantly lower scotopic b-wave amplitudes (130.2 ± 39.3 µV vs.163.3 ± 47.8 µV, p < 0.01) and photopic b-wave amplitudes (83.2 ± 20.7 µV vs. 99.6 ± 29.4 µV, p < 0.01) in the diabetic patients. The implicit time of the photopic responses was significantly prolonged (28.9 ± 1.3 ms vs. 27.8 ± 2.1 ms, p = 0.01) in the patients. Oscillatory potentials in all components consisting of O1 to O4 and the sum of the OP potentials were lower in the diabetic group than the control subjects (p < 0.001). The P50 and N95 amplitudes and implicit times were comparable between the groups (p > 0.05). Correlation analysis showed a positive correlation between N95 amplitudes in pERG and the superficial vessel densities in OCTA (r = 0.26, p = 0.04). A negative correlation was found between photopic implicit times in fERG and the choriocapillary vessel densities (r=-0.27, p = 0.03). CONCLUSION: OCTA revealed decreased superficial vascular densities with the onset of the metabolic process of diabetes mellitus. As a result of these structural changes, lower scotopic and photopic amplitudes, decreased OP amplitudes, and prolonged implicit times in flash ERG were obtained.


Asunto(s)
Electrorretinografía , Tomografía de Coherencia Óptica , Humanos , Electrorretinografía/métodos , Masculino , Tomografía de Coherencia Óptica/métodos , Femenino , Persona de Mediana Edad , Anciano , Adulto , Angiografía con Fluoresceína/métodos , Retinopatía Diabética/fisiopatología , Retinopatía Diabética/diagnóstico por imagen , Vasos Retinianos/diagnóstico por imagen , Vasos Retinianos/fisiopatología , Estudios de Casos y Controles , Fóvea Central/diagnóstico por imagen , Fóvea Central/irrigación sanguínea , Fóvea Central/fisiopatología , Diabetes Mellitus/fisiopatología , Diabetes Mellitus/diagnóstico por imagen , Retina/diagnóstico por imagen , Retina/fisiopatología
8.
Heliyon ; 10(17): e36453, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39263072

RESUMEN

This article presents a novel approach to predict the flash temperature of biodiesel and ethanol mixtures using the Group Contribution Method (GCM). Expanding on the pioneering work by Liaw et al. (2003), our method employs GCM to calculate the activity coefficients of biodiesel and ethanol components in the mixture. Estimating these coefficients, crucial for accurate flash temperature prediction, involves a comprehensive analysis of composition, functional groups, and vapor-liquid equilibrium (VLE) data. For this purpose, the composition of the mixture components in biodiesel, the functional groups within each biodiesel component, the composition ratios of biodiesel and ethanol in the mixture, and the functional groups present in ethanol are considered. Given that the use of UNIQUAC and NRTL models requires estimating adjustable parameters, VLE data for ethanol and biodiesel mixtures are employed to calculate the activity coefficients. This approach not only aids in estimating these coefficients but also facilitates determining the values associated with each functional group. Flash temperature predictions for biodiesel and ethanol mixtures obtained through various models, including the ideal solution, UNIQUAC, NRTL, and our proposed GCM, are rigorously assessed. The results indicate that the GCM method outperforms the alternatives, exhibiting the lowest error with a deviation of just 1.72 K compared to deviations of 1.77 K, 1.75 K, and 1.73 K for the ideal solution, UNIQUAC, and NRTL models, respectively. This research offers a promising approach for flash point estimation in complex systems, such as biodiesel-ethanol blends, contributing to the ongoing exploration in this field.

9.
Nanomaterials (Basel) ; 14(17)2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39269042

RESUMEN

Cancer is a major public health problem that ranks as the second leading cause of death. Anti-cancer drug development presents with various hurdles faced throughout the process. Nanoparticle (NP) formulations have emerged as a promising strategy for enhancing drug delivery efficiency, improving stability, and reducing drug toxicity. Previous studies have shown that the adamantyl retinoid ST1926 displays potent anti-tumor activities in several types of tumors, particularly in colorectal cancer (CRC). However, phase I clinical trials in cancer patients using ST1926 are halted due to its low bioavailability. In this manuscript, we developed ST1926-NPs using flash nanoprecipitation with polystyrene-b-poly (ethyleneoxide) as an amphiphilic stabilizer and cholesterol as a co-stabilizer. Dynamic light scattering revealed that the resulting ST1926-NPs Contin diameter was 97 nm, with a polydispersity index of 0.206. Using cell viability, cell cycle analysis, and cell death assays, we showed that ST1926-NP exhibited potent anti-tumor activities in human CRC HCT116 cells. In a CRC xenograft model, mice treated with ST1926-NP exhibited significantly lowered tumor volumes compared to controls at low drug concentrations and enhanced the delivery of ST1926 to the tumors. These findings highlight the potential of ST1926-NPs in attenuating CRC tumor growth, facilitating its further development in clinical settings.

10.
Schizophr Res ; 274: 137-141, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39293251

RESUMEN

Retinal electrophysiological alterations are implicated in psychosis, but their relationship with cognition in early course psychosis (ECP) is understudied. The Brief Assessment of Cognition (BAC) and flash electroretinography (fERG) were conducted in 24 controls (HC) and 27 ECP individuals. Partial Spearman correlations were performed between fERG and BAC. Lower Photopic-1b and Scotopic-3b amplitudes were identified in ECP vs. HCs. Correlations were significant (p<0.05) between BAC Composite score and a-wave S3a and S2a and b-wave S2b and S3b conditions. Thus, ECP was characterized by lower ERG responses, and lower rod/cone/bipolar cell responses were related to poorer cognition.

11.
Radiother Oncol ; : 110534, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39293721

RESUMEN

BACKGROUND AND PURPOSE: Ultra-high dose-rate radiotherapy (FLASH) has been shown to mitigate normal tissue toxicities associated with conventional dose rate radiotherapy (CONV) without compromising tumor killing in preclinical models. A prominent challenge in preclinical radiation research, including FLASH, is validating both the physical dosimetry and the biological effects across multiple institutions. MATERIALS AND METHODS: We previously demonstrated dosimetric reproducibility of two different electron FLASH devices at separate institutions using standardized phantoms and dosimeters. In this study, tumor-free adult female mice were given 10 Gy whole brain FLASH and CONV irradiation at both institutions and evaluated for the reproducibility and temporal evolution of multiple neurobiological endpoints. RESULTS: FLASH sparing of behavioral performance on novel object recognition (4 months post-irradiation) and of electrophysiologic long-term potentiation (LTP, 5 months post-irradiation) was reproduced between institutions. Differences between FLASH and CONV on the endpoints of hippocampal neurogenesis (Sox2, doublecortin), neuroinflammation (microglial activation), and electrophysiology (LTP) were not observed at early times (48 h to 2 weeks), but recovery of immature neurons by 3 weeks was greater with FLASH. CONCLUSION: In summary, we demonstrated reproducible FLASH sparing effects on the brain between two different beams at two different institutions with validated dosimetry. FLASH sparing effects on the endpoints evaluated manifested at later but not the earliest time points.

12.
Radiother Oncol ; 200: 110507, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39245070

RESUMEN

Treatments at ultra-high dose rate (UHDR) have the potential to improve the therapeutic index of radiation therapy (RT) by sparing normal tissues compared to conventional dose rate irradiations. Insufficient and inconsistent reporting in physics and dosimetry of preclinical and translational studies may have contributed to a reproducibility crisis of radiobiological data in the field. Consequently, the development of a common terminology, as well as common recording, reporting, dosimetry, and metrology standards is required. In the context of UHDR irradiations, the temporal dose delivery parameters are of importance, and under-reporting of these parameters is also a concern.This work proposes a standardization of terminology, recording, and reporting to enhance comparability of both preclinical and clinical UHDR studies and and to allow retrospective analyses to aid the understanding of the conditions which give rise to the FLASH effect.

13.
Med Phys ; 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39284344

RESUMEN

BACKGROUND: Ultra-high dose rate irradiation (≥40 Gy/s, FLASH) has been shown to reduce normal tissue toxicity, while maintaining tumor control compared to conventional dose-rate radiotherapy. The radiolytic oxygen (O2) depletion (ROD) resulting from FLASH has been proposed to explain the normal tissue protection effect; however, in vivo experiments have not confirmed that FLASH induced global tissue hypoxia. Nonetheless, the experiments reported are based on volume-averaged measurement, which have inherent limitations in detecting microscopic phenomena, including the potential preservation of stem cells niches due to local FLASH-induced O2 depletion. Computational modeling offers a complementary approach to understand the ROD caused by FLASH at the microscopic level. PURPOSE: We developed a comprehensive model to describe the spatial and temporal dynamics of O2 consumption and transport in response to irradiation in vivo. The change of oxygen enhancement ratio (OER) was used to quantify and investigate the FLASH effect as a function of physiological and radiation parameters at microscopic scale. METHODS: We considered time-dependent O2 supply and consumption in a 3D cylindrical geometry, incorporating blood flow linking the O2 concentration ([O2]) in the capillary to that within the tissue through the Hill equation, radial and axial diffusion of O2, metabolic and zero-order radiolytic O2 consumption, and a pulsed radiation structure. Time-evolved distributions of [O2] were obtained by numerically solving perfusion-diffusion equations. The model enables the computation of dynamic O2 distribution and the relative change of OER (δROD) under various physiological and radiation conditions in vivo. RESULTS: Initial [O2] level and the subsequent changes during irradiation determined δROD distribution, which strongly depends on physiological parameters, i.e., intercapillary spacing, ultimately determining the tissue area with enhanced radioresistance. We observed that the δROD/FLASH effect is affected by and sensitive to the interplay effect among physiological and radiation parameters. It renders that the FLASH effect can be tissue environment dependent. The saturation of FLASH normal tissue protection upon dose and dose rate was shown. Beyond ∼60 Gy/s, no significant decrease in radiosensitivity within tissue region was observed. In turn, for a given dose rate, the change of radiosensitivity became saturated after a certain dose level. Pulse structures with the same dose and instantaneous dose rate but with different delivery times were shown to have distinguishable δROD thus tissue sparing, suggesting the average dose rate could be a metric assessing the FLASH effect and demonstrating the capability of our model to support experimental findings. CONCLUSION: On a macroscopic scale, the modeling results align with the experimental findings in terms of dose and dose rate thresholds, and it also indicates that pulse structure can vary the FLASH effect. At the microscopic level, this model enables us to examine the spatially resolved FLASH effect based on physiological and irradiation parameters. Our model thus provides a complementary approach to experimental methods for understanding the underlying mechanism of FLASH radiotherapy. Our results show that physiological conditions can potentially determine the FLASH efficacy in tissue protection. The FLASH effect may be observed under optimal combination of physiological parameters, not limited to radiation conditions alone.

14.
Nanomaterials (Basel) ; 14(15)2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39120394

RESUMEN

The production of graphene from cost-effective and readily available sources remains a significant challenge in materials science. This study investigates the potential of common pencil leads as precursors for graphene synthesis using the Flash Joule Heating (FJH) process. We examined 6H, 4B, and 14B pencil grades, representing different graphite-to-clay ratios, under varying voltages (0 V, 200 V, and 400 V) to elucidate the relationships among initial composition, applied voltage, and resulting graphene quality. Samples were characterized using Raman spectroscopy, electrical resistance measurements, and microscopic analysis. The results revealed grade-specific responses to applied voltages, with all samples showing decreased electrical resistance post-FJH treatment. Raman spectroscopy indicated significant structural changes, particularly in ID/IG and I2D/IG ratios, providing insights into defect density and layer stacking. Notably, the 14B pencil lead exhibited unique behavior at 400 V, with a decrease in the ID/IG ratio from 0.135 to 0.031 and an increase in crystallite size from 143 nm to 612 nm, suggesting potential in situ annealing effects. In contrast, harder grades (6H and 4B) showed increased defect density at higher voltages. This research contributes to the development of more efficient and environmentally friendly methods for graphene production, potentially opening new avenues for sustainable and scalable synthesis.

15.
Small ; : e2404364, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39115351

RESUMEN

Ultrahigh-temperature Joule-heating of carbon nanostructures opens up unique opportunities for property enhancements and expanded applications. This study employs rapid electrical Joule-heating at ultrahigh temperatures (up to 3000 K within 60 s) to induce a transformation in nanocarbon aerogels, resulting in highly graphitic structures. These aerogels function as versatile platforms for synthesizing customizable metal oxide nanoparticles while significantly reducing carbon emissions compared to conventional furnace heating methods. The thermal conductivity of the aerogel, characterized by Umklapp scattering, can be precisely adjusted by tuning the heating temperature. Utilizing the aerogel's superhydrophobic properties enables its practical application in filtration systems for efficiently separating toxic halogenated solvents from water. The hierarchically porous aerogel, featuring a high surface area of 607 m2 g-1, ensures the uniform distribution and spacing of embedded metal oxide nanoparticles, offering considerable advantages for catalytic applications. These findings demonstrate exceptional catalytic performance in oxidative desulfurization, achieving a 98.9% conversion of dibenzothiophene in the model fuel. These results are corroborated by theoretical calculations, surpassing many high-performance catalysts. This work highlights the pragmatic and highly efficient use of nanocarbon structures in nanoparticle synthesis under ultrahigh temperatures, with short heating durations. Its broad implications extend to the fields of electrochemistry, energy storage, and high-temperature sensing.

16.
Cureus ; 16(7): e63947, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39105008

RESUMEN

OBJECTIVES: This study aimed to assess the correlation between glycated hemoglobin A1 (HbA1c), time in range (TIR), and glycemic management indicator (GMI) in patients with both type 1 diabetes (T1D) and type 2 diabetes (T2D) who were using a flash glucose monitoring (FGM) device (FreeStyle Libre; Abbott Diabetic Care, Witney, UK). METHODS: This was a retrospective study that looked at T1D and T2D FreeStyle Libre users' LibreView database in the period between January 2020 to June 2022. The study was conducted at the diabetes department at the King Fahad Medical City (KFMC) in Riyadh, Saudi Arabia, following Institutional Review Board (IRB) approval. Data were collected from the LibreView website, as well as from the electronic privacy information center (EPIC) hospital records. RESULTS: Data were available for 327 patients, mean age of 33.08(±17.1) years old, and 55.7% were females. HbA1c had a statistically significant correlation with both TIR and GMI with coefficient of correlation (r) values of 0.78 (p<0.001) and 0.82 (p<0.001), respectively. A linear regression model between TIR and Hb1Ac was also developed and found to be statistically significant (p<0.001) with an acceptable R2 value (0.60). CONCLUSION: Study findings revealed that the %TIR could be a reliable predictor of Hb1Ac. Thus, Freestyle Libre was able to determine Hb1Ac as close to the lab results as possible. Therefore, it is necessary to encourage diabetes patients to achieve at least 70% TIR in order to keep Hb1Ac within the desired range.

17.
ArXiv ; 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39148931

RESUMEN

The design and optimization of laser-Compton x-ray systems based on compact distributed charge accelerator structures can enable micron-scale imaging of disease and the concomitant production of beams of Very High Energy Electrons (VHEEs) capable of producing FLASH-relevant dose rates. The physics of laser-Compton x-ray scattering ensures that the scattered x-rays follow exactly the trajectory of the incident electrons, thus providing a route to image-guided, VHEE FLASH radiotherapy. The keys to a compact architecture capable of producing both laser-Compton x-rays and VHEEs are the use of X-band RF accelerator structures which have been demonstrated to operate with over 100 MeV/m acceleration gradients. The operation of these structures in a distributed charge mode in which each radiofrequency (RF) cycle of the drive RF pulse is filled with a low-charge, high-brightness electron bunch is enabled by the illumination of a high-brightness photogun with a train of UV laser pulses synchronized to the frequency of the underlying accelerator system. The UV pulse trains are created by a patented pulse synthesis approach which utilizes the RF clock of the accelerator to phase and amplitude modulate a narrow band continuous wave (CW) seed laser. In this way it is possible to produce up to 10 µA of average beam current from the accelerator. Such high current from a compact accelerator enables production of sufficient x-rays via laser-Compton scattering for clinical imaging and does so from a machine of "clinical" footprint. At the same time, the production of 1000 or greater individual micro-bunches per RF pulse enables > 10 nC of charge to be produced in a macrobunch of < 100 ns. The design, construction, and test of the 100-MeV class prototype system in Irvine, CA is also presented.

18.
Med Phys ; 2024 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-39153223

RESUMEN

BACKGROUND: Ultra high dose rate (UHDR) radiotherapy using ridge filter is a new treatment modality known as conformal FLASH that, when optimized for dose, dose rate (DR), and linear energy transfer (LET), has the potential to reduce damage to healthy tissue without sacrificing tumor killing efficacy via the FLASH effect. PURPOSE: Clinical implementation of conformal FLASH proton therapy has been limited by quality assurance (QA) challenges, which include direct measurement of UHDR and LET. Voxel DR distributions and LET spectra at planning target margins are paramount to the DR/LET-related sparing of organs at risk. We hereby present a methodology to achieve experimental validation of these parameters. METHODS: Dose, DR, and LET were measured for a conformal FLASH treatment plan involving a 250-MeV proton beam and a 3D-printed ridge filter designed to uniformly irradiate a spherical target. We measured dose and DR simultaneously using a 4D multi-layer strip ionization chamber (MLSIC) under UHDR conditions. Additionally, we developed an "under-sample and recover (USRe)" technique for a high-resolution pixelated semiconductor detector, Timepix3, to avoid event pile-up and to correct measured LET at high-proton-flux locations without undesirable beam modifications. Confirmation of these measurements was done using a MatriXX PT detector and by Monte Carlo (MC) simulations. RESULTS: MC conformal FLASH computed doses had gamma passing rates of >95% (3 mm/3% criteria) when compared to MatriXX PT and MLSIC data. At the lateral margin, DR showed average agreement values within 0.3% of simulation at 100 Gy/s and fluctuations ∼10% at 15 Gy/s. LET spectra in the proximal, lateral, and distal margins had Bhattacharyya distances of <1.3%. CONCLUSION: Our measurements with the MLSIC and Timepix3 detectors shown that the DR distributions for UHDR scenarios and LET spectra using USRe are in agreement with simulations. These results demonstrate that the methodology presented here can be used effectively for the experimental validation and QA of FLASH treatment plans.

19.
Diabetes Ther ; 15(9): 2109-2118, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39102115

RESUMEN

INTRODUCTION: There is a growing body of evidence demonstrating the benefit of flash glucose monitoring in people living with type 2 diabetes mellitus (T2DM). This real-world study aimed to evaluate the effect of initiating flash glucose monitoring on change in HbA1c after 3-6 months in adults living with T2DM treated with multiple daily injections of insulin. METHODS: A retrospective observational study using data from ten clinical centres in the UK for adults with T2DM treated with multiple daily injections of insulin for at least 1 year was conducted. Patients who had been using the FreeStyle Libre/Libre 2 Flash Glucose Monitoring System for at least 3 months with baseline HbA1c 64-108 mmol/mol (8.0-12.0%) recorded up to 3 months prior to system use were included. Pregnant patients and those on dialysis were excluded. Patients with an HbA1c value measured 3-6 months after commencing flash glucose monitoring were included in the final analysis for evaluation of change. RESULTS: In total, 87 patients were included in the final analysis (mean age, 60.0 ± 11.8 years, 60.9% male, mean body mass index (BMI), 31.6 ± 5.4 [mean ± SD]). From a mean baseline HbA1c of 80 ± 11 mmol/mol (9.5% ± 1.0%), HbA1c lowered by 11 ± 14 mmol/mol (1.0% ± 1.3%) at 3-6 months (p < 0.0001). A decrease was observed independent of age, baseline HbA1c, sex, duration of insulin use and BMI subgroups. CONCLUSIONS: Initiation of flash glucose monitoring was associated with a clinically and statistically significant improvement in HbA1c in a real-world setting at 3-6 months.

20.
Front Hum Neurosci ; 18: 1441915, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39175660

RESUMEN

The human brain is sensitive to threat-related information even when we are not aware of this information. For example, fearful faces attract gaze in the absence of visual awareness. Moreover, information in different sensory modalities interacts in the absence of awareness, for example, the detection of suppressed visual stimuli is facilitated by simultaneously presented congruent sounds or tactile stimuli. Here, we combined these two lines of research and investigated whether threat-related sounds could facilitate visual processing of threat-related images suppressed from awareness such that they attract eye gaze. We suppressed threat-related images of cars and neutral images of human hands from visual awareness using continuous flash suppression and tracked observers' eye movements while presenting congruent or incongruent sounds (finger snapping and car engine sounds). Indeed, threat-related car sounds guided the eyes toward suppressed car images, participants looked longer at the hidden car images than at any other part of the display. In contrast, neither congruent nor incongruent sounds had a significant effect on eye responses to suppressed finger images. Overall, our results suggest that only in a danger-related context semantically congruent sounds modulate eye movements to images suppressed from awareness, highlighting the prioritisation of eye responses to threat-related stimuli in the absence of visual awareness.

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