Azobenzene derivatives are becoming increasingly popular in pharmacology due to their improved selectivity based on trans-cis isomerization upon light irradiation. In the context of ion channels, one of the conformations may block ion conduction, while the other allows it. We studied an azobenzene derivative, DAD, designed with the aim of avoiding excitation wavelengths in the UV region of the...
Electroluminescence (EL) is the phenomenon of light emission, by a material, following electron impact in the presence of an external electric field. Gas Proportional Scintillation Counters (GPSC) use this effect in noble gases as an amplification process of the ionization signal induced by radiation interaction in the gas. Several geometries have been proposed and developed for this type of...
Primary scintillation in Xe for electrons and alpha-particles Content Gaseous xenon (GXe) is playing an increasingly significant role in important areas of neutrino physics such as double beta decay and double electron capture experiments and is a potential alternative to MeV-region γ-ray imaging. The precise knowledge of the xenon response to radiation interactions in both scintillation and...
Wave-Length Shifting (WLS) fibers are optical fibers specially designed to shift the wavelength of incident ultraviolet or blue light to longer wavelengths, namely green light. The usage of WLS fibers for xenon scintillation readout offers several advantages, including enhanced light yield due to efficient conversion of UV/blue scintillation photons to visible light, reduced sensitivity to...
Global concern about the high environmental impact of hydrofluorocarbons (HFCs) led the Kyoto Protocol to list these compounds as potent greenhouse gases. For that reason, hydrofluoroethers (HFEs) were proposed for substitution of HFCs in several applications, such as refrigerants, because of their relatively low global warming potential (GWP). Therefore, it is important to evaluate the impact...
In the last years, several C-bearing and (C,N)-bearing chains of molecular anions have been detected in the interestellar medium (ISM). Since experimental treatments are still challenging, computational methods have to be used to understand their chemistry. The C$_5$N$^-$ anion is one of the largest (C,N)-bearing chains and, although there are several theoretical studies [1-3] that describe...
The presence of (micro)-plastics in different aquatic environments is a matter of world concern that has been gaining importance in recent years due to its potential impact on the environment and human health. (Micro)-plastics have been found in practically all types of water bodies and the presence of metals in these materials, either due to their manufacture or through adsorption processes,...
Alkyl nitrites (R$-$ONO, R$=$CH$_3$, n-C$_3$H$_7$, t-C$4$H$9$) have been widely studied due to the efficient photodissociation and formation of NO fragment.[1,2] The absorption spectra of all these molecules present two bands. A first band characterized by a clear vibronic structure, and a second more intense band which extends to the VUV energy reagion.[2,3] In this work, three different...
The detection of ionizing radiation is of vital importance in various branches of science, medicine, border security and environmental monitoring, among others. The development of new detection systems that have versatility of applications, of easy production and manipulation with viable costs has been one of the fields of application of many recent studies, namely in the field of neutron...
Several studies show that the combination of high-Z nanoparticles (NPs) and external radiotherapy (RT) leads to an increased radiation effect in tumoral cells without an increase of the patient dose [1,2]. Among the various elements with sensitizing potential, Au NPs have been the most studied due to the greater biocompatibility of gold. In this technique, Au NPs are incorporated inside tumor...
Due to its similarity with ammonia (NH$_3$) and because it has been observed in the interstellar medium,[1] methylamine (CH$_3$NH$_2$) has received considerable attention in the last decades. The molecular photodissociation of methylamine was studied using the pump-probe method with nanosecond laser pulses. The molecule was excited in the 198 $-$ 203 nm range, and the generated photofragments...
Every time an intervention is performed, the total (biopsy) or a portion (surgery) of normal and tumor tissue is retrieved and processed as Formalin Fixed Paraffin Embedded (FFPE) blocks for the diagnosis and after they are stored for safekeeping. These FFPE blocks contain precious information regarding the elemental composition of normal/tumor tissue that is not harvested because there is no...
Carlos M. R. Rocha1, Octavio Roncero2, Niyazi Bulut2,*, Piotr Zuchowski3, and Asunción Fuente4
1Laboratory for Astrophysics, Leiden Observatory, Leiden University, PO Box 9513, 2300-RA, Leiden, The Netherlands
2Instituto de Física Fundamental (IFF-CSIC), C.S.I.C., Serrano 123, 28006 Madrid, Spain
3Institute of Physics, Faculty of Physics, Astronomy, and Informatics, Nicolaus Copernicus...
The plasma divertor for the International Termonuclear Experimental Reactor (ITER) will have target plates made out of tungsten (W) [1]. The inevitable W contamination will emit characteristic radiation that depends on the specific charge state balance, electron temperature and density conditions. Therefore, the respective emission spectra can be used as real-time diagnostics of the fusion...
He hydrates present an intriguing and relatively unexplored systems. As they may have significant implications in fields such as planetary science, exploration of novel ice phases, such as ultra-low density ices or superionic water ice, and the development of innovative materials with distinct properties and applications, such as solid electrolyte in batteries, understanding their fundamental...
Aldehydes are very important trace gases for the physical chemistry of the troposphere mainly because they are directly emitted into the atmosphere or formed in situ from the photooxidation of organic compounds. In particular, the unsaturated aldehyde trans-2-methyl-2-pentenal (T2M2P) is emitted into the low atmosphere from several sources such as wildland fires, vegetation, and from some...
Raman spectroscopy (RS) is a highly-sensitive optical technique based on specific vibrations of molecules, which enables non-invasive and non-destructive monitoring of biospecimens present in tissues, revealing disease-prompted variations and allowing to differentiate healthy from malignant samples with high accuracy, sensitivity and specificity. Nevertheless, pigmented tissues are...
In this study, we investigated the elemental distribution of heavy metals in Zebrafish (Danio rerio) using an X-ray fluorescence system that relies on a gaseous detector. The primary objective was to analyze the presence and spatial distribution of heavy metals within the tissues of Zebrafish specimens. The employed X-ray fluorescence system, which incorporated a THCOBRA detector, allowed for...
Particleboard (PB) is produced using 50% to 75% recycled wood, with the possibility of reaching 100% recycled content, while Medium Density Fiberboard (MDF) is mostly made with virgin wood [1]. The presence of physical and chemical contaminants in wood waste may compromise its incorporation in recycling facilities. While physical contaminants as nails, joints, glass, textiles, etc., are easier...
Lipid membranes are highly complex and dynamic systems formed by hundreds of different types of lipids combined in specific ratios. Many pathological cells exhibit significant alterations in the lipid composition of their membranes when compared to healthy cells. For example, lipid profile singularities have been found in cancer, bacterial and viral infections and even in senescent cells...
An overview of our experimental program to detect QCD axions and axion-like-particles (ALPs) as possible candidates for dark matter (DM) using NMR techniques within the cosmic axion spin precession experiment (CASPEr) is presented [1]. ALPs are hypothetical particles that could also solve the strong CP violation problem, and it is predicted that the axion field would behave as a classical...
α-pinene is the most abundant monoterpene in the atmosphere and its oxidation yields to several oxygenated species that play a major role in the formation of secondary organic aerosols. α-pinene oxide (C$_{10}$H$_{16}$O) is generated from the reaction of ozone with α-pinene and has been shown to contribute to the formation of organosulfates under atmospheric conditions. Thus, understanding its...
In recent years, the COVID pandemic has garnered a great deal of attention, focusing mainly on the acute phase of the disease. However, this is only the beginning, as some patients continue to experience persistent symptoms, known as Post-COVID Condition (PCC), and an estimated 20% of those affected do not recover.The presence of this condition shows a number of obstacles, including the lack...
Molybdenum disulfide (MoS$_2$) is a two-dimensional (2D) semiconductor that has attracted significant attention due to its properties, such as a band gap energy dependent on the layers’number and a large specific surface area prone to chemical functionalization. These properties make 2D MoS$_2$ an excellent platform for optical sensing applications [1,2]. For example, the combination of...
The interaction of an electron with the dipole field of a neutral atom or molecule can lead to radiative photon emission by analogy with the familiar case of Nuclear Bremsstrahlung. This process is referred to as Neutral Bremsstrahlung and is possible even in noble atoms due to their induced dipole moment. Neutral bremsstrahlung in noble gases has been neglected in favor of excimer-based...
The development of light sources in the extreme ultraviolet (XUV) based on high harmonic generation has opened new avenues for the investigation of time-resolved photodynamics in cationic excited electronic states of polyatomic molecules. Here, an XUV pump-infrared (IR) probe scheme with femtosecond time resolution is employed to study the dynamics of dissociative ionization in methyl iodide...
Extreme Ultraviolet (EUV) table-top sources and soft to hard X-ray Free Electron lasers (XFELs) have opened a new era in science, providing ultrashort, coherent, and tunable pulses that are used to perform cutting-edge experiments in Atomic and Molecular physics, Condensed Matter Physics, Biology and Chemistry. However, most of the reported studies rely on linear light-matter interactions,...
Lipid cellular membranes constitute a common factor to all known Life on Planet Earth. It is this commonness, and yet their distinctions based on cell type, organism, or age[1] what makes them attractive targets for a wide range of treatments. Therefore, it is of paramount importance to understand how these ubiquitous structures react to different stimuli. Specifically, their mechanical...
In this Poster, we will present a proposal for a robust gamma radiation detector system for aerial mapping and radiation surveillance. It entails assembling and calibrating the detector using four high-resolution crystals and studying the effects of a VETO system. The detector will be equipped with real-time communication capabilities and AI algorithms for data analysis and source...
The photodissociation of dihalomethanes have received significant attention due to its role in producing pollutant species and ozone depletion.[1] Moreover, CH$_2$BrI presents an intricate structure of excited electronic states and a high bond selectivity. For instance, the A absorption band was attributed to C-I dissociation, while the A' band corresponds to C-Br bond fission.[2] However, the...
Attosecond probing of core-to-valence electronic transitions is a powerful tool for real-time observation of chemical dynamics.[1] Here, ultrafast extreme ultraviolet (XUV) transient absorption spectroscopy is employed to investigate the electronic and nuclear dynamics on small polyatomic iodinated molecules. The dynamics induced by one- or two-photon absorption using either few-femtosecond...
The kinetic study of neutral-neutral reactions in the gas phase at ultralow temperatures is undergoing a huge advancement over the last decades [1]. Such studies have exponentially increased due to the increasing number of new molecules detected in the interstellar medium (ISM), specially in the coldest regions (10-100 K). To model the chemistry occurring in these extreme environments, the...
Quantum Electrodynamics (QED) effects have been tested and measured in multiple systems, including free electrons, atomic and highly charged ions systems. Frequentist statistical analyses either point to a possible deviation from the theory prediction [1] of n = 2 → 1 transitions energy in two-electron systems with a dependency of Z^3, Z indicating the nuclear charge, or find no disagreement...
Argon gaseous detectors have been widely used in dark matter search and neutrino experiments over the last decade, owing to their unique ionization and scintillation characteristics. The primary and secondary scintillation in argon mainly result from the radiative de-excitation of singlet and triplet excimer states produced at gas pressures above 100 mbar. This well-known light production...
Medical imaging plays a crucial role in the diagnosis and treatment of various diseases and conditions. It allows healthcare professionals to visualize internal structures and processes of the body without the need for invasive procedures. Medical imaging techniques include x-ray, computed tomography (CT), magnetic resonance imaging (MRI), and ultrasound, among others. Position sensitive gas...
We have revisited and enlarged the vibrational analysis of diacetyl or 2,3-butanedione by means of state-of-the-art Raman spectroscopy [1] and quantum chemical computations. The Raman spectra were obtained previously only in condensed phases [2] and hence hindered low-energy vibrational modes were undetected. Here we measured the Raman spectra of diacetyl in all the gas and liquid phases and...
Gaseous neutron detectors are crucial tools to many scientific fields, as neutrons are used to probe matter, revealing structures and functions not accessible by other imaging means. 3He filled multi-wire chambers are being replaced by novel instruments coated with thick layers of boron,as 3He is now almost exclusively used for security applications. I will present a novel approach which...
Sulfur-containing heterocycles hoard a major scientific interest for its key role in natural and pharmaceutical products [1,2]. One of these compounds is 2-(2-pyridyl)benzo[b]thiophene, a heterobiarylic molecule whose structural insights are addressed here using computational methods and rotational spectroscopy.
Theoretical calculations have included density functional predictions (B3LYP-D3...
Para-aminobenzoic acid is a formerly used UVB filter that was found to react with the DNA when exposed to sunlight.[1] Molecular Dynamics (MD) and Umbrella Sampling simulations show that the neutral species of PABA binds favourably DNA by intercalation between two nucleobase pairs, while the binding of the anionic species is not feasible from the thermodynamic and kinetic points of view....
Imine-based molecular switches were recently developed, and so their properties remain largely unexplored[1]. Their potential to perform multi-step unidirectional rotations make them an important addition to the existing nanomotor toolbox[2]. Microwave rotational spectroscopy allows us to study the 3D structure of these molecules with great precision since we can relate the pattern of...
X-ray imaging is an invaluable tool for noninvasive analysis in many fields ranging from basic science to medicine and security. The development of low-dose large area imaging solutions still represents an important challenge for various applications.
One solution to the imaging of large areas lies in the development of novel computational imaging systems that can overcome the limitations...
