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The Space Radiobiological Exposure Facility on the China Space Station.

The Space Radiobiological Exposure Facility (SREF) is a general experimental facility at the China Space Station for scientific research in … nd images and videos of such experiments can be captured by microscopy. SREF also includes a linear energy transfer (LET) detector, neutron detectors, and a solar ultraviolet (UV) detector to measure the LET spectrum of the charged particles, energy spectrum and dose equivalent of neutrons, and fluence of solar UV radiation, respectively. The facility is reusable …

Nanosensor-Based Pattern-Generating Probe Accelerates Sepsis Diagnosis.

Biomimetic optical sensor arrays hold promising potential in differentiating nuances within intricate mixtures and biosamples. Nonetheless, developing a standalone pattern-generating sensor for multianalyte identification in clinical biofluids, without the necessity of complicated synthesis, presents significant challenges. Here, we introduce a nanosensor-inspired sensor array (NanoSA), composed of a nanoassembly incorporating three sensors, that exhibits multiple intermolecular fluorescence resonance energy transfer (FRET) effects. This pattern-generating nanoassembly, featuring six channels,…

Characterizing diamond detectors for various dose and dose rate measurements in scanned carbon and oxygen beams.

BACKGROUND: The emerging FLASH radiotherapy technique employs "Ultra-High Dose Rate" (UHDR) irradiations and offers the potential to spare normal tissue while maintaining iso-effective tumor treatment. Given the physical and biological advantages inherent to high "Linear Energy Transfer" (LET) particles, the combination of UHDR and high LET has the capability to enhance the normal tissues sparing, as indicated by initial in vivo trials. However, to ensure a safe implementation of this combined modality, it is essential to establish robust dosimetric protocols utilizing dose-, dose rate-, and L…

Activity-Based Fluorescent Probes for Sensing and Imaging of Reactive Carbonyl Species (RCSs).

This review explains various strategies for developing fluorescent probes to detect reactive carbonyl species (RCS). There are several mono … on transfer (PeT), excited-state intramolecular proton transfer (ESIPT), and fluorescence resonance energy transfer (FRET) are described. In particular, probes for dicarbonyls such as methylglyoxal (MGO), malondialdehyde (MDA), along with monocarbonyls that include formaldehyde (FA), carbon monoxide (CO) and phosgene are discussed. One of the most exciting advanc …

Highly sensitive fluorescent aptasensor based on MoS2 nanosheets for one-step determination of methamphetamine.

In this work, a simple and sensitive fluorescence aptasensor based on MoS2 nanosheets (MoS2-Ns) combined with a fluorophore-labeled aptamer (aptamer-FAM) for MTA determination in one step has been described. The aptamer-FAM can be spontaneously absorbed by the surface of MoS2-Ns to form an aptamer-FAM/MoS2-Ns' sensing platform, resulting in quenching of the fluorescence of aptamer-FAM largely. However, after introducing the target MTA, the fluorescence will be restored depending on the levels of MTA added. Such an above reaction platform possesses a linear correlation of between 5 and 2400 nM,

Theoretical investigation on FRET strategy of ratio metric fluorescent probe sensing hydrogen sulfide.

The level of hydrogen sulfide (H2S) in human body is related to many diseases, such as Alzheimer's disease, Down syndrome, etc. Therefore, the detection of H2S level in biological systems is very important and has attracted great attention from scientific and clinical researchers. Understanding the design and working mechanism of fluorescent probes for H2S level detection is important for building new highly efficient fluorescent probe. The mechanisms of a recently reported efficient small molecule fluorescent probe based on the Fluorescence Resonance Energy Transfer (FRET) were investigated t…

Оптимизация анализа насыщенности БРЕТ для надежных и чувствительных исследований взаимодействия цитосолика и протеина.

Насыщение биолюминесцентным резонансом передачи энергии (BRET) является методом изучения взаимодействия белка и протеина (PPI) при количественной оценке зависимости сигнала BRET от отношения к выражению приемщика/донора (A:D). В этом исследовании, используя очень яркую пару Nluc/YPF BRET, приобретенную соответственно с помощью микрозвукового считывателя и автоматизированной конфокальной микроскопии, мы значительно улучшили анализ насыщенности BRET путем расширения диапазона обнаружения выражения A:D и нормализации выражения A:D с помощью нового зонда, свободного от BRET. Далее мы обнаружили, ч

Совпадение в аннотации оригинала
Bioluminescence resonance energy transfer (BRET) saturation is a method of studying protein-protein interaction (PPI) upon quantification of the dependence of the BRET signal on the acceptor/donor (A:D) expression ratio. In this study, using the very bright Nluc/YFP BRET pair acquired respectively with microplate reader and automated confocal microscopy, we …

A Simple Determination of Trinitrotoluene (TNT) Based on Fluorescence Quenching of Rhodamine 110 with FRET Mechanism.

Sensitive and selective detection of nitroaromatic explosives is an important issue in regard to human health, environment, public security … ne complex can strongly quench the fluorescence emission of Rhodamine 110 by fluorescence resonance energy transfer (FRET) which occurs as the excited Rhodamine 110 fluorophore (donor) transfers its energy to TNT (acceptor) by non-radiative dipole-dipole interaction. Fluorescence quenching varied linearly with TNT concentration, with LOD and the LOQ of 0.71 and 2 …

Single-Peptide TR-FRET Detection Platform for Cysteine-Specific Post-Translational Modifications.

Post-translational modifications (PTMs) are one of the most important regulatory mechanisms in cells, and they play key roles in cell signal … ultifunctionality of the assay. Thus, we have developed a sensitive time-resolved Förster resonance energy transfer (TR-FRET) detection method for PTMs of cysteine residues using a single-peptide approach performed in a 384-well format. In the developed assay, the enzyme-specific biotinylated substrate peptide is post-translationally modified at the cysteine resi …

A Quantum Dot Nanobiosensor for Rapid Detection of Botulinum Neurotoxin Serotype E.

Botulinum neurotoxins (BoNTs) are potent toxins produced by Clostridium bacteria that are responsible for the illness botulism and are liste … even fewer methods usable for BoNT serotyping. We report a nanobiosensor based on Förster resonance energy transfer (FRET) between semiconductor nanocrystals (quantum dots, QDs) and dark quencher-labeled peptide probes to detect biologically active BoNT/E in aqueous media. The peptide probes contain a specific cleavage site for active BoNT/E. QD photoluminescence …

Simultaneous binding of a cyclophane and classical intercalators to DNA: observation of FRET-mediated white light emission.

DNA-assisted Förster resonance energy transfer (FRET) between an anthracene-based cyclophane (CP) and mono- and bis-intercalators such as propidium iodide (PI) and ethidium homodimer-1 (EHD), respectively, has been studied using various photophysical and biophysical techniques. The cyclophane and PI exhibited simultaneous binding to DNA at all concentrations studied and showed DNA-assisted FRET from the excimer of cyclophane with a FRET efficiency of ca. 71%. On the other hand, the bis-intercalator EHD, only at lower concentrations (<3 μM), can act as an acceptor for the energy transfer proces…

A dual FRET based fluorescent probe as a multiple logic system.

A new fluorescent probe with a unique sequential dual FRET process was designed and constructed. This probe showed distinguished responses towards Fe(3+) and Hg(2+), making it an ideal candidate for multiple logic operations at the molecular level.

A ratiometric fluorescent probe for cyanide based on FRET.

On the basis of FRET from 4-(N,N-dimethylamino)benzamide to fluorescein, a new ratiometric fluorescence probe bearing a hydrazone binding unit was developed for highly selective and sensitive detection of CN(-) in aqueous solution.

Phagosomal acidification: measurement, manipulation and functional consequences.

Phagocytosis holds a central position in the development of a successful innate immune response and in the initiation of the corresponding adaptive response. The destruction of invading pathogens and the presentation of their antigens to lymphoid cells require acidification of the phagosomal lumen. The present review discusses the mechanism of phagosome acidification, with particular reference to the two components of the protonmotive force: the chemical (pH) gradient and the electrical potential across the phagosomal membrane. A method for the in situ measurement of the electrical potential a

Motion energy versus position tracking: spatial, temporal, and chromatic parameters.

The fundamental question in motion perception is whether motion is an interpretation imposed on an object or feature perceived at separate positions at sequential instants, or whether it is the response of direction-sensitive detectors that can extract the motion-energy in the stimulus, i.e. the orientation of spatio-temporal energy. To answer this question we constructed stimuli whose position changed in one direction while the motion energy contained in the same spatial frequency moved in the same or the opposite direction (by superimposing moving sinusoidal gratings on stationary gratings o

Effect of LET on chromosomal aberration yields. I. Do long-lived, exchange-prone double strand breaks play a role?

Dicentric chromosomal aberrations produced by ionizing radiation probably result from pairwise interaction of DNA double strand breaks (dsbs). It has been suggested that high LET radiation may preferentially produce a subclass of 'severe' dsbs that are long-lived and/or exchange-prone, and that it is the production of these severe dsbs which account for the increased biological effectiveness of high-LET radiation. We present a quantitative formalism to describe the induction of these severe dsbs, and the subsequent production of exchange-type chromosomal aberrations. Using a Markov model and m

Experimental gallstone dissolution with methyl-tert-butyl ether (MTBE) and transcutaneous ultrasound energy.

The simultaneous application of ultrasound energy greatly accelerated the rate of cholesterol gallstone dissolution by methyl-tert-butyl ether (MTBE). In vitro experiments using this treatment showed that a 498-mg stone burden could be dissolved in 19.5 minutes, approximately 100% faster than what could be achieved with MTBE alone. Pigs (n = 13) with surgically implanted gallstones were treated with MTBE and transcutaneously applied ultrasound from a prototype system built for clinical studies. The average stone reduction of all pigs was 470.46 mg +/- 60.44 mg; 91.39% of an average implanted b

[Relation of the radiosensitivity of yeast cells to the LET of the radiation. Effect of additional growth and its contribution to resistance and the shape of the survival curve of diploid cells].

A study was made of the contribution of the additional growth effect to the survival rate of Saccharomyces cerevisiae diploid yeasts and its influence on the survival curve shape after exposure to ionizing radiation of different linear energy transfer (LET). The effect of the additional growth was shown to be the only factor responsible for a sigmoid shape of the survival curve of diploid yeasts affected by high LET radiation. As LET increased the contribution of the additional growth effect to the survival rate decreased: this was due to the pattern of cell distribution by the number of radia…

Exploring adsorption mechanism of hydrogen cyanide and cyanogen chloride molecules on arsenene nanoribbon from first-principles.

The SIESTA package is employed in examining the electronic and adsorption features of the toxic asphyxiants hydrogen cyanide (HCN) and cyanogen chloride (NCCl) on armchair arsenene (As-arm) nanoribbon. Based on the generalized gradient approximation (GGA) with the Perdew-Burke-Ernzerhof (PBE) level of theory, we explored the adsorption of HCN and NCCl on As-arm nanoribbon. The significant parameters necessary to validate the electronic and stable nature of As-arm nanoribbon are computed with the help of formation energy and energy gap change. The density of states (DOS) spectrum and the energy

Titanium and zinc oxide nanoparticles are proton-coupled electron transfer agents.

Oxidation/reduction reactions at metal oxide surfaces are important to emerging solar energy conversion processes, photocatalysis, and geochemical transformations. Here we show that the usual description of these reactions as electron transfers is incomplete. Reduced TiO(2) and ZnO nanoparticles in solution can transfer an electron and a proton to phenoxyl and nitroxyl radicals, indicating that e(-) and H(+) are coupled in this interfacial reaction. These proton-coupled electron transfer (PCET) reactions are rapid and quantitative. The identification of metal oxide surfaces as PCET reagents ha