Absorption Of Radiation Research Articles

Biomimetic MOF nanoplatform for dual-targeted co-delivery of FAK inhibitor and bismuth to enhance cervical cancer radiosensitivity

Radiation therapy (RT) remains the primary treatment modality for advanced cervical cancer, however, recurrence due to radioresistance presents a significant challenge. Cancer-associated fibroblasts (CAFs) within the tumor microenvironment (TME) are key contributors to this resistance, driven by their inherent radioresistance and radiation-induced phenotypic adaptations. Addressing this issue requires strategies specifically designed to target CAFs and enhance their radiosensitivity. In this study, we developed a biomimetic metal–organic framework (MOF) nanoplatform for the dual-targeted co-delivery of the FAK inhibitor IN10018 and Bismuth (Bi), aimed at improving radiosensitivity in cervical cancer. The IN10018 and Bi-loaded zeolitic imidazolate framework 8 (ZIF-8) nanoparticles (IZB) were further coated with hybrid membranes derived from CAFs and cancer cells, enabling precise targeting of both cell types. Upon exposure to an acidic environment, the nanoparticles disassemble, releasing IN10018, which reduces CAFs infiltration and enhances radiosensitivity. Simultaneously, the incorporation of Bi enhances radiation absorption efficiency, further sensitizing tumor cells to radiotherapy. This dual-target strategy represents a promising approach to overcoming radioresistance in cervical cancer and exemplifies how integrating nanotechnology with targeted therapies can enhance RT efficacy and improve patient outcomes.Graphic Schematic Illustration of IZB@CCM Construction and Application for Cervical Cancer to Improve Radiosensitivity. (1) IZB was fabricated through the one-pot method. (2) Preparation of hybrid CAF-cancer cell membrane. (3) IZB@CCM were obtained by co-extrusion of IZB and hybrid membrane (CCM). (4) IZB@CCM demonstrated the ability to target CAFs and cancer cells. (5) IZB@CCM inhibited the expression of FAK and released radiosensitizer Bi to enhance the radiosensitivity of cervical cancer.

Surface Pressure Semidiurnal Tides and the Stratospheric Quasi‐Biennial Oscillation: Synchronization and Disruption

AbstractAtmospheric surface pressure provides valuable information on the vertical dynamical structure of the atmosphere. Previous studies have reported that among the waves observed in surface pressure, semidiurnal tides (SDTs) are significantly affected by the stratospheric Quasi‐Biennial Oscillation (QBO). Using historical surface‐pressure observations and the Earth‐system model MRI‐ESM2.0, this study confirms that SDTs and the QBO are synchronized, such that SDT amplitude increases or decreases, respectively, at a rate of ∼1 Pa per 20 ms−1 during westerly or easterly phases of the QBO at 30 hPa. Our numerical simulations and a linear analytical model support the QBO‐SDT relationship being dynamically forced by background zonal winds rather than by anomalous ozone radiative heating. We also find that the QBO‐SDT relationship was notably disturbed by the volcanic eruptions of Mount Agung in 1963 and Mount Pinatubo in 1991, during which increased shortwave radiative absorption caused by stratospheric aerosol enhanced the SDT amplitude. Short‐lived El Nino events also occurred, moistening the upper troposphere to provide extra solar heating when volcanic aerosol was transported to higher latitudes. The influence of volcanic eruptions and El Nino events overlap with the QBO frequency band, jointly working as “noise” in QBO‐SDT synchronization.

Development of biocompatible mesoporous silica materials for enhanced UV protection

AbstractA new class of mesoporous silica (MPS)‐based biocompatible ultraviolet (UV) protective materials (1–4) has been prepared and characterized. These materials, which include avobenzone (AV)‐encapsulated MPS, were modified with biphenyl‐4‐triethoxysilane and polyethylene glycol (PEG200). Their photostability was tested under a sun‐simulated lamp. It was found that the structure of the material significantly impacts UV protection performance. Specifically, encapsulating AV‐enhanced UV radiation absorption, while the biphenyl layer improved UV‐blocking capabilities. Additionally, the PEG layer increased the materials' biocompatibility. Materials 1–4 demonstrated critical wavelengths of 389 nm and UV‐A/UV‐B ratios ranging from 0.61 to 0.89. Notably, the sun protection factor values were estimated between 6.04 and 17.24. In vivo testing on nude mice showed that untreated skin exhibited significant epidermal thickening due to sunburn. In contrast, skin treated with material 3 did not show any epidermal thickening, being 14 times thinner than unprotected skin. With high stability against photodegradation, materials 1–4 are promising candidates for UV protection applications, with material 3 proving to be the most effective.

Influence of Dufour, Hall, and radiation absorption on MHD convective flow past an accelerated perpendicular sheet implanted with porous medium

Influence of Dufour, Hall, and radiation absorption on MHD convective flow past an accelerated perpendicular sheet implanted with porous medium

Air–Ice–Water Temperature and Radiation Transfer Via Different Surface Coverings in Ice-Covered Qinghai Lake of the Tibetan Plateau

There are numerous lakes in the Tibetan Plateau (TP) that significantly impact regional climate and aquatic ecosystems, which often freeze seasonally owing to the high altitude. However, the special warming mechanisms of lake water under ice during the frozen period are poorly understood, particularly in terms of solar radiation penetration through lake ice. The limited understanding of these processes has posed challenges to advancing lake models and improving the understanding of air–lake energy exchange during the ice-covered period. To address this, a field experiment was conducted at Qinghai Lake, the largest lake in China, in February 2022 to systematically examine thermal conditions and radiation transfer across air–ice–water interfaces. High-resolution remote sensing technologies (ultrasonic instrument and acoustic Doppler devices) were used to observe the lake surface changes, and MODIS imagery was also used to validate differences in lake surface conditions. Results showed that the water temperature under the ice warmed steadily before the ice melted. The observation period was divided into three stages based on surface condition: snow stage, sand stage, and bare ice stage. In the snow and sand stages, the lake water temperature was lower due to reduced solar radiation penetration caused by high surface reflectance (61% for 2 cm of snow) and strong absorption by 8 cm of sand (absorption-to-transmission ratio of 0.96). In contrast, during the bare ice stage, a low reflectance rate (17%) and medium absorption-to-transmission ratio (0.86) allowed 11% of solar radiation to penetrate the ice, reaching 11.70 W·m−2, which increased the water temperature across the under-ice layer, with an extinction coefficient for lake water of 0.39 (±0.03) m−1. Surface coverings also significantly influenced ice temperature. During the bare ice stage, the ice exhibited the lowest average temperature and the greatest diurnal variations. This was attributed to the highest daytime radiation absorption, as indicated by a light extinction coefficient of 5.36 (±0.17) m−1, combined with the absence of insulation properties at night. This study enhances understanding of the characteristics of water/ice temperature and air–ice–water solar radiation transfer through effects of different ice coverings (snow, sand, and ice) in Qinghai Lake and provides key optical radiation parameters and in situ observations for the refinement of TP lake models, especially in the ice-covered period.

Phototoxic Effects on Skin Biomolecules Induced by a Domestic Nail Polish Dryer Device.

UVA radiation and visible light can lead to indirect damage to DNA, proteins, and lipids through photosensitized reactions, where a molecule undergoes a photochemical alteration by the initial absorption of radiation by another molecular entity called photosensitizer (Sens). The chemical changes undergone by biomolecules in photosensitized reactions can trigger important adverse processes such as photoallergy, phototoxicity, and skin cancer, among others. Despite the knowledge about photosensitized reactions and the fact that many endogenous compounds present in the skin can act as Sens, UVA, and visible light are widely used in several devices for domestic and general use without a thorough evaluation of their possible harmful effects; one prominent example is UV-nail polish dryers. The information in the literature about the possible damage that can be caused by using this type of radiation source is controversial. In this work, we demonstrate that the radiation dose emitted by the nail polish dryer device during a typical gel nail manicure session effectively degrades molecules present in the skin under physiological and pathological conditions. Additionally, it may induce damage to biomolecules such as proteins and lipids due to the photosensitization process, leading to the loss of their biological functions.

A terahertz-driven controllable water nanopump

Manipulating water flow in nanochannels is crucial for advancing nanotechnology and nanofluidic. Using molecular dynamics simulation, we demonstrate that both the direction and rate of flow in a uniform nanochannel can be precisely tuned by varying the incident direction, field intensity, and irradiation range of a specific-frequency biased terahertz pulse stimulation, without requiring any external pressure gradients. The resonant coupling between the irradiated water molecules and terahertz pulses is revealed to create pressure gradients that determine the direction of water flow and control the flow rate. This effect is attributed to the asymmetric absorption of terahertz radiation by water molecules within the nanochannel, which generates a controllable energy flow. These insights provide a glorious inspiration for designing advanced nanofluidic devices that require facile and stable energy flow control, avoiding physical intrusion.

Comparison of the mechanisms of DNA damage following photoexcitation and chemiexcitation

In this review, we compare the mechanisms and consequences of electronic excitation of DNA via photon absorption or photosensitization, as well as by chemically induced generation of excited states. The absorption of UV radiation by DNA is known to produce cyclobutane pyrimidine dimers (CPDs) and thymine pyrimidone photoproducts. Photosensitizers are known to enable such transformations using UV-A and visible light by generating triplet species able to transfer energy to DNA. Conversely, chemiexcitation of DNA is a process related to the formation of high energy peroxides whose decomposition leads to triplet excited species. In practice, both photoexcitation and chemiexcitation produce reactive excited species able to promote some DNA nucleobases to their excited state. We discuss the effect of epigenetic methylation modifications of DNA and the role of endogenous and exogenous photosensitizers on the formation of DNA photoproducts via triplet-triplet energy transfer as well as oxidative DNA damages. The mechanisms of pathogenic pathway involving the generation of CPDs via chemiexcitation (namely dark CPDs, dCPDs) are discussed and compared with photoexcitation considering their spatiotemporal characteristics. Recognition of the multifaceted noxious effects of UV radiation opens new horizons for the development of effective electronically excited quenchers, thereby providing a crucial step toward mitigating DNA photodamage.

Effect of CF4 plasma treatment on the THz radiation absorption of vertically aligned carbon nanotubes

Effect of CF4 plasma treatment on the THz radiation absorption of vertically aligned carbon nanotubes

Observed determinants of urban outdoor thermal exposure during hot summer and snowy winter periods in a humid continental climate

Many cities in the midlatitudes experience both extreme heat and cold, and pedestrians are exposed to thermal extremes that cause bodily stress. With growing urban populations, city design that contributes to mitigating summer heat while reducing winter cold exposure is increasingly important. Pedestrian thermal exposure depends on several microclimatic factors, including shortwave and longwave radiation absorption, which can be quantified by the mean radiant temperature (Tmrt). Limited research has been conducted on the radiative components of thermal exposure in hot, humid summers and cold, snowy winters. We gathered micrometeorological data from diverse urban sites and in multiple seasons in Guelph, Canada, using a mobile human-biometeorological weather station (MaRTy cart) that applies the six-directional method to determine Tmrt. Seasonal datasets were analysed and compared to examine the drivers of thermal exposure and recommend strategies for mitigating heat and cold stress. In summer, shade is the primary factor that reduces daytime heat exposure and it slightly increases nighttime heat exposure. Enhanced pervious ground cover is a secondary factor day and night. In winter, reduced shade alleviated daytime cold exposure, while snow cover provided daytime benefits from increased solar reflections and post-sunset penalties associated with reduced longwave radiation from low snow surface temperatures.

A Review on Strategies to Enhance the On-Body Read Range of Passive UHF RFID Tag

Passive Ultra-High-Frequency Radio Frequency Identification (UHF RFID) tag has been implemented as a wearable device for numerous healthcare applications. However, the tag possesses limitations owing to the absorption of electromagnetic radiation by the human body, which significantly reduces the read range of the tag. Thus, the potential strategies to mitigate the effect of the human body need to be addressed. Recently, significant efforts have been made to overcome this shortcoming by incorporating metamaterials or introducing slots to the tag antenna structure. Therefore, this article provides insight into strategies that specifically employ slots, Artificial Magnetic Conductor (AMC), and Split Ring Resonator (SRR). Prior to this, the factors affecting the read range and previously reported studies are briefly discussed. Finally, the future directions for further improvement of these strategies are discussed.

Advances in nanomaterials for radiation protection in the aerospace industry: a systematic review.

Nanomaterials stand out for their exceptional properties and innovative potential, especially in applications that protect against space radiation. They offer an innovative approach to this challenge, demonstrating notable properties of radiation absorption and scattering, as well as flexibility and lightness for the development of protective clothing and equipment. This review details the use of polymeric materials, such as polyimides (PIs), which are efficient at attenuating ultraviolet (UV) radiation and atomic oxygen (AO). For example, polyimides show a decrease in elongation at break by 10% after exposure to VUV radiation of 2000 equivalent solar hours (ESH). The thermal stability under vacuum ultraviolet (VUV) irradiation shows that colorless polyimides like CPI-T/Al exhibit an onset degradation temperature of 451°C, while CPI-L/Al shows a degradation onset of 439° C. Additionally, advancements in composite materials for gamma and neutron radiation shielding are covered. Materials such as fluorinated hyperbranched polyimides (FHBPI) display a decomposition temperature of approximately 450°C, which ensures structural integrity during space missions involving radiation. Radiation absorption and scattering properties of these composites are assessed, with materials such as W-Bi2O3 demonstrating a high linear attenuation coefficient (LAC) of 2.5 MeV, enhancing their efficiency in protecting against gamma radiation. Mechanical and optical changes, such as a 15% increase in solar absorbance after exposure to VUV, are critical for prolonged space missions. Moreover, the integration of nanoparticles like graphene and carbon nanotubes into polymers has proven to be an efficient strategy for improving the shielding properties and stability of materials. Nanocomposites like BNTT-Ti display a neutron transmission reduction of 20%, further validating their potential for space applications. Future investigations will focus on optimizing the functionality, manufacturing, and compatibility of composite materials, as well as validating their performance under actual space mission conditions. Collaboration among material scientists, aerospace engineers, and space agencies is vital to transforming laboratory discoveries into viable solutions for radiation protection in space.

Magnetohydrodynamic buoyancy-driven flow of chemically reactive ternary hybrid nanofluid over a moving porous vertical surface with radiation absorption and heat source

Magnetohydrodynamic buoyancy-driven flow of chemically reactive ternary hybrid nanofluid over a moving porous vertical surface with radiation absorption and heat source

Investigation of Gamma Radiation Shielding Properties of Bi2O3-TeO2-Li2O-Al2O3 Coated Glasses With Geant4-Monte Carlo Gate and XCOM Simulation

This article aims to investigate the effect of Bi2O3-TeO2-Li2O-Al2O3 coated glasses on radiation absorption properties and to develop alternative materials for radiation protection. The shielding properties of glass materials coated with oxides were calculated theoretically using the XCOM computer program and the Geant4-Monte Carlo-GATE simulation program. By calculating mass absorption coefficients (MAC) at 662 keV, 1173 keV, and 1332 keV energies, linear absorption coefficient (LAC), half-value thickness (HVL), and mean free path (MFP) values were calculated. In line with these results, it is seen that the radiation shielding feature of the LiAlTeBi4 mixture is better than other materials and can be an alternative shielding material.

Effect of Relaxation Times on Magnetization of Blood Proton Spins at Steady State using Improved Bloch NMR Fluid Flow Equation

Nuclear magnetic resonance (NMR) is a phenomenon that involves the absorption and re-emission of electromagnetic radiation by blood proton spins flowing through human vessels. NMR is governed by Bloch NMR fluid flow equation, which can be used to define the magnetization of blood proton spins. In the existing literature, the Bloch NMR fluid flow equation has been derived, and it has been observed that the equation does not incorporate certain NMR and blood flow parameters. In this paper, we derived a novel Bloch NMR magnetization flow equation that encompasses NMR parameters such as Larmor frequency of spinning protons and static magnetic field. We utilized the principle of dimensional homogeneity to check the validity of our newly derived NMR flow equation. Furthermore, we investigated the effect of transverse relaxation times of arterial, venous and capillary blood on magnetization of blood spinning protons. We employed Laplace transform method to obtain the steady state solution of the improved Bloch NMR fluid flow equation. MATLAB and Origin software tools were used for data analysis and simulations. Results showed that for varied transverse relaxation times of arterial, venous and capillary blood, respectively, the magnetization distribution of blood spinning protons consists of two components: the linear and the non-linear components. The findings of the study also indicated that capillary blood proton spins exhibit phase coherence. The simulated results may be used by spectroscopists to improve the accuracy of NMR/magnetic resonance imaging (MRI) experiments.

Application of Infrared Thermography in Identifying Plant Oils.

In this article, we present a unique system for identifying edible oils through the analysis of their thermophysical properties. The method is based on the use of active infrared thermography. The heating of the oils results from the optical absorption of laser radiation at a specified wavelength. This approach enables greater selectivity in differentiating between various types of edible oils, as the results depend not only on the thermal properties of the specific oils but also on their optical properties, which are uniquely characteristic of each oil. Additionally, the developed system provides a detailed visualization of spatial temperature gradients within the sample's volume, as well as their changes over time. It overcomes the limitations of other methods that determine only the thermal conductivity coefficients of oils through resistive heating of the sample. In this article, four types of vegetable oils (extra virgin olive oil, sesame oil, sunflower oil, and rapeseed oil) have been studied. Fatty acid analysis, differential scanning calorimetry, and UV-VIS spectroscopy have been used to determine the authenticity, moisture content, and optical properties of the studied samples. The developed system allows for the visualization and determination of the emerging temperature gradients in the sample volume.

Model of interaction between laser radiation and metal powder composition during direct laser growth

This paper presents a model for analyzing the interaction of laser radiation and a metal-powder composition in the process of direct laser growing of large-sized combustion chambers of gas turbine engines. The metal-powder composition is fed into the melting zone coaxially with laser radiation; the task is to completely melt the powder with laser radiation before it enters the melt bath on the construction platform. The laser radiation is absorbed as it passes through the gas-powder jet, and its energy is also used to melt the construction platform or the previous layer. Thus, in order to determine the parameters of the operating conditions that provide the possibility of melting powder particles, it is necessary to determine the boundaries of the parameters at which each particle of the metal-powder composition completely melts in a gas-powder jet. To simulate heat transfer inside a particle, the Beer – Lambert laser radiation absorption law was used using the lumped parameter approach. The required energy for melting the powder material was determined through enthalpy. The resulting one-dimensional differential equation of enthalpy increment is solved numerically by the Euler method. Using this model, the distance from the point of origin of the interaction of the laser beam with a metal-powder composition to the zone of its complete melting was determined and the effect of the velocity of the gas-powder jet, the power of laser radiation, the bulk density of the metal-powder composition and the average radius of the powder particles on the distance to the zone of complete melting was studied.

Thermoplastic Composite Hot-Melt Adhesives with Metallic Nano-Particles for Reversible Bonding Techniques Utilizing Microwave Energy.

This study investigated the creation of nano-composites using recycled LDPE and added 7.5 wt% nanofillers of Al and Fe in two varying particle sizes to be used as hot-melt adhesives for reversible bonding processes with the use of microwave technology. Reversible bonding relates to circular economy enhancement practices, like repair, refurbishment, replacement, or renovation. The physical-chemical, mechanical, and dielectric characteristics were considered to determine the impact of particle size and metal type. Through the investigation of electromagnetic radiation absorption in the composites, it was discovered that the optimal bonding technique could potentially involve a frequency of 915 MHz and a power level of 850 × 103 W/kg, resulting in an efficient process lasting 0.5 min. It was ultimately proven that the newly created hot-melt adhesive formulas can be entirely recycled and repurposed for similar bonding needs.

Evaluation of January-to-April-2016 strong El Niño event impacts on the land surface radiation absorption along the west coast of Peru

ABSTRACT Clarifying the El Niño impacts on regional land surface radiation absorption (SRA) could deepen our understanding of El Niño’s climate change driving mechanisms. In this study, impacts from the January-to-April-2016 strong El Niño event on SRA along the west coast of Peru are evaluated based on the Deep Space Climate Observatory (DSCOVR) Earth Polychromatic Imaging Camera (EPIC) dataset, which could provide longer-term, more consistent and higher temporal sampling rate observations, to complement current low-orbit-satellite-based research. Results show that the strong El Niño events lasting from January to April in 2016 would substantially reduce the SRA in the low-latitude region (latitudes ranges from 3° S to 7° S) of Peru by decreasing the regional atmospheric transmittance. It is also found that such negative El Niño impacts on SRA become weaker at higher-latitude regions in Peru.

Tunable perfect absorption of microwave radiation via dielectric slabs in irregular arrangements

Tunable perfect absorption of microwave radiation via dielectric slabs in irregular arrangements