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Purpose: Conventionally, keratoconus (KC) has been considered a noninflammatory corneal ectatic disorder. Recent evidence suggests a possible role of inflammation in the pathogenesis of KC. Hence, we analyzed the levels of inflammatory factors in the tear fluid of Indian KC patients. Methods: Tear fluid samples were collected from age-and sex-matched healthy controls and KC patients (with different grades). The levels of the inflammatory factors in tears were analyzed using cytometric bead array (Human Soluble Protein Flex Set System, BD Biosciences) for levels of interleukin-1 alpha (IL-1 alpha), IL-1 beta, IL-2, IL-4, IL-5, IL-6, IL-8, IL-9, IL-10, IL-12p70, IL-23p40, IL-13, IL-17A, IL-17F, IL-21, interferon-alpha (IFN alpha), IFN., tumor necrosis factor-alpha, CCL2/monocyte chemotactic protein-1, CCL4/macrophage inflammatory protein-1 beta (MIP-1 beta), MIP-1 alpha, CCL5/RANTES, CXCL10/IP10, ICAM1, CD62E, vascular endothelial growth factor and transforming growth factor beta. Results: An increase in Kmax and Kmean, and a decrease in central corneal thickness was observed with increasing grades of KC. Tear analysis showed that most of the tear soluble factors, including cytokines, chemokines, growth factors and cell adhesion molecules were significantly elevated in the KC patients compared to the controls. Conclusion: Our findings suggest that inflammatory factors associated with KC may play a role in its pathogenesis. This opens the potential to explore anti-inflammatory strategies to either halt or delay the progression of KC.

The Periodic Table, and the unique chemical behavior of the first element in a column (group), were discovered simultaneously one and a half centuries ago. Half a century ago, this unique chemistry of the light homologs was correlated to the then available atomic orbital (AO) radii. The radially nodeless 1s, 2p, 3d, 4f valence AOs are particularly compact. The similarity of r (2s)≈r(2p) leads to pronounced sp‐hybrid bonding of the light p‐block elements, whereas the heavier p elements with n≥3 exhibit r (ns) ≪ r (np) of approximately −20 to −30 %. Herein, a comprehensive physical explanation is presented in terms of kinetic radial and angular, as well as potential nuclear‐attraction and electron‐screening effects. For hydrogen‐like atoms and all inner shells of the heavy atoms, r (2s) ≫ r (2p) by +20 to +30 %, whereas r (3s)≳r(3p)≳r(3d), since in Coulomb potentials radial motion is more radial orbital expanding than angular motion. However, the screening of nuclear attraction by inner core shells is more efficient for s than for p valence shells. The uniqueness of the 2p AO is explained by this differential shielding. Thereby, the present work paves the way for future physical explanations of the 3d, 4f, and 5g cases., 2p or not 2p? Similarity of radii (and energies) of the atomic valence orbitals is the precondition for hybridization and hybrid bonding. In the Coulomb potential of H‐like atoms, the 2p orbital without a radial node is much smaller than 2s (2s≫2p), whereas higher p orbitals are comparably less contracted (ns≳np). The screening of nuclear attraction by the core shells is more effective for the core penetrating s orbitals, so that for the valence orbital radii of ordinary many‐electron atoms of the 2nd row, 2s≈2p, whereas in rows n>2, hybridization is less pronounced owing, i.a., to ns≪ np.

Fast pyrolysis of biomass results in a renewable product usually denoted pyrolysis oil or bio-oil, which has been suggested to be used as a direct substitute for fuel oil or as a feedstock for production of transportation fuels and/or chemicals. In the present work, fast pyrolysis of stem wood (originated from pine and spruce), willow, reed canary grass, brown forest residue and bark has been performed in a pilot scale cyclone reactor. The experiments were based on a biomass feeding rate of 20 kg/h at three different reactor temperatures. At the reference condition, pyrolysis of stem wood, willow, reed canary grass, and forest residue resulted in organic liquid yields in the range of 41 to 45% w /w, while pyrolysis of bark resulted in lower organic liquid yields. Two fractions of pyrolysis oil were obtained, denoted as the condensed and the aerosol fraction. Most of the water soluble molecules were collected in the condensed fraction, whereas the yield of water insoluble, heavy lignin molecules was higher in the aerosol fraction. Based on the results of the present work, willow, reed canary grass and forest residue are considered as promising raw materials for production of pyrolysis oil in a cyclone reactor.

In this work, we utilize a short-wavelength, 532-nm picosecond pulsed laser coupled with a time-gated complementary metal-oxide semiconductor (CMOS) single-photon avalanche diode (SPAD) detector to acquire Raman spectra of several drugs of interest. With this approach, we are able to reveal previously unseen Raman features and suppress the fluorescence background of these drugs. Compared to traditional Raman setups, the present time-resolved technique has two major improvements. First, it is possible to overcome the strong fluorescence background that usually interferes with the much weaker Raman spectra. Second, using the high photon energy excitation light source, we are able to generate a stronger Raman signal compared to traditional instruments. In addition, observations in the time domain can be performed, thus enabling new capabilities in the field of Raman and fluorescence spectroscopy. With this system, we demonstrate for the first time the possibility of recording fluorescence-suppressed Raman spectra of solid, amorphous and crystalline, and non-photoluminescent and photoluminescent drugs such as caffeine, ranitidine hydrochloride, and indomethacin (amorphous and crystalline forms). The raw data acquired by utilizing only the picosecond pulsed laser and a CMOS SPAD detector could be used for identifying the compounds directly without any data processing. Moreover, to validate the accuracy of this time-resolved technique, we present density functional theory (DFT) calculations for a widely used gastric acid inhibitor, ranitidine hydrochloride. The obtained time-resolved Raman peaks were identified based on the calculations and existing literature. Raman spectra using non-time-resolved setups with continuous-wave 785- and 532-nm excitation lasers were used as reference data. Overall, this demonstration of time-resolved Raman and fluorescence measurements with a CMOS SPAD detector shows promise in diverse areas, including fundamental chemical research, the pharmaceutical setting, process analytical technology (PAT), and the life sciences. Graphical abstract Time-resolved Raman measurement of a pharmaceutical sample using the complementary metal-oxide semiconductor (CMOS) single photon avalanche diode (SPAD) detector technology Electronic supplementary material The online version of this article (doi:10.1007/s00216-015-9156-6) contains supplementary material, which is available to authorized users.

The availability of natural gas hydrates and the continuing increase in energy demand, motivated researchers to consider gas hydrates as a future source of energy. Fundamental understanding of hydrate dissociation kinetics is essential to improve techniques of gas production from natural hydrates reservoirs. During hydrate dissociation, bonds between water (host molecules) and gas (guest molecules) break and free gas is released. This paper investigates the evolution of hydrate surface area, pore habit, and tortuosity using in-situ imaging of Xenon (Xe) hydrate formation and dissociation in porous media with dynamic three-dimensional synchrotron microcomputed tomography (SMT). Xe hydrate was formed inside a high- pressure, low-temperature cell and then dissociated by thermal stimulation. During formation and dissociation, full 3D SMT scans were acquired continuously and reconstructed into 3D volume images. Each scan took only 45 seconds to complete, and a total of 60 scans were acquired. Hydrate volume and surface area evolution were directly measured from the SMT scans. At low hydrate saturation, the predominant pore habit was surface coating, while the predominant pore habit at high hydrate saturation was pore filling. A second-degree polynomial can be used to predict variation of tortuosity with hydrate saturation with an R2 value of 0.997. The Authors, published by EDP Sciences, 2020. This publication was made possible by partial funding from NPRP grant # NPRP8-594-2-244 from the Qatar national research fund (a member of Qatar Foundation) and the Institute for a Secure and Sustainable Environment (ISSE), University of Tennessee-Knoxville, USA. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of funding agencies. The authors would like to thank Mr. Wadi Imseeh for his help during scanning and Mr. Jamal Hannun for his help in interfacial area analysis. This paper used resources of the Advanced Photon Source (APS), a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory (ANL) under Contract No. DE-AC02-06CH11357. The PSMT images presented in this paper were collected using the x-ray Operations and Research Beamline Station 13-BMD at Argonne Photon Source (APS), ANL. We thank Dr. Mark Rivers of APS for help in performing the PSMT scans. We also acknowledge the support of GeoSoilEnviroCARS (Sector 13), which is supported by the National Science Foundation, Earth Sciences (EAR-1128799), and the DOE, Geosciences (DEFG02-94ER14466). Scopus

Hydrogen bonds impact many material properties due to the bond directionality and collective strength. For them to exist, the atoms connected to hydrogen should possess high electronegativity, the distance between the interacting atoms should be less than their van der Waals radii, and there should be a charge transfer between them. In hybrid perovskites, the impact of hydrogen bonds is ascribed to several phenomena. Among them are the effect of passivation at the surface, structural stability of the mixed cation compounds, structural instability of FAPbI3, and ferroelectric behavior. In this paper, we applied a deterministic method to prove the existence of hydrogen bonds using Raman spectroscopy. This approach was successfully applied to water and is based on the emergence of a Raman mode as a result of the intermolecular charge transfer, which is not measured for the isolated molecule. With the help of DFT calculations, we attributed the Raman modes detected at room temperature (RT) for MAI and FAI and compared them with the Raman spectra of MAPbX3 and FAPbX3. This comparison has shown that there are no hydrogen bonds in hybrid lead halide perovskites at RT.

International audience; Unravelling the atomic scale diffusion that can occur at the surface, at the interface or into the bulk is challenging: multi-scale modelling approaches usually require intensive prospective calculations and moreover huge human investment. In this article, the Static Mode (SM) approach is coupled with Quantum Mechanics (QM) calculations in order to guide the exploration of the energy landscape, by optimizing the choice of events that are significant for the evolution of the system. SM enable the determination of the strain field of a set of atoms submitted to external and localized stresses, like atomic displacements. Here, we present a workflow based on the systematic SM exploration, with the objective to reduce both exploration time and human load when used with ab initio level calculations. The QMSM coupling allows the screening, scoring and selection of relevant directions that are further used to initiate and study diffusion in atomic systems. The most relevant deformations are then refined and relaxed with DFT calculations. In this paper, the overall QMSM approach is described and we discuss its use for the identification of atomic diffusion in two different systems of interest: grafting of a molecule on an oxide surface and studying the dynamical behavior of a point-defect in a bulk crystalline material.

International audience; The use of quantitative structure–property relationships (QSPRs) helps in predicting molecular properties for several decades, while the automatic design of new molecular structures is still emerging. The choice of algorithms to generate molecules is not obvious and is related to several factors such as the desired chemical diversity (according to an initial dataset’s content) and the level of construction (the use of atoms, fragments, pattern-based methods). In this paper, we address the problem of molecular structure generation by revisiting two approaches: fragment-based methods (FMs) and genetic-based methods (GMs). We define a set of indices to compare generation methods on a specific task. New indices inform about the explored data space (coverage), compare how the data space is explored (representativeness), and quantifies the ratio of molecules satisfying requirements (generation specificity) without the use of a database composed of real chemicals as a reference. These indices were employed to compare generations of molecules fulfilling the desired property criterion, evaluated by QSPR.

The cellular level of nicotinamide adenine dinucleotide (NAD(+)), through its different functions, affects cellular metabolism and signalling(1-3). A decrease in the NAD(+) content has been associated with various pathologies and physiological aging(4,5), while strategies to boost cellular NAD(+) levels have been shown to be effective against age-related diseases in many animal models(6). The link between decreased NAD(+) levels and numerous pathologies and physiological aging has triggered the need for a simple quantification method for NAD(+), ideally applicable at the point of care. Here, we introduce a bioluminescent biosensor for the rapid quantification of NAD(+) levels in biological samples, which can be used either in laboratories or at the point of care. The biosensor is a semisynthetic, light-emitting sensor protein that changes the colour of emitted light from blue to red on binding of NAD(+). This NAD(+)-dependent colour change enables the use of the biosensor in paper-based assays in which NAD(+) is quantified by measuring the colour of the emitted light by using either a simple digital camera or a plate reader. We used the approach to quantify NAD(+) levels in cell culture, tissue and blood samples, yielding results that agreed with those from standard testing methods. The same biosensor furthermore allows the quantification of NAD(+)-dependent enzymatic activities in blood samples, thus expanding its utility as a tool for point-of-care diagnostics.

In this paper, we characterize amino acids and nucleic acid bases (nucleobases), such as glutamine, histidine, tyrosine, adenine, guanine, cytosine, and thymine, and examine their interaction with bare, as well as with gold cluster and Ti adatom covered, black phosphorene (α-P) monolayers using density functional theory. The binding of these amino acids and nucleobases to the bare α-P monolayer is realized generally through weak van der Waals interaction and comprises only a small amount of charge exchange. Accordingly, the electronic energy structures of adsorbates and underlying substrate are not affected significantly. However, the electronic structure of bare α-P is significantly affected upon adsorption of a gold cluster and a single Ti adatom; depending on the size of the adsorbate and the symmetry of their coverage, the energy band gap can be tuned and permanent magnetic moments can be attained. Additionally, the adsorption of amino acids or nucleobases to these adsorbates on an α-P monolayer results in enhanced binding and hence makes their sustainable fixation on α-P monolayer possible. In particular, a semiconducting Au decorated α-P monolayer undergoes a metal–insulator transition upon the adsorption of tyrosine. This and similar effects favor the α-P monolayer in biosensor applications. In contrast to the situation with adsorbates, the binding of amino acid is not enhanced when it adsorb to patterned vacancy or divacancy sites of the α-P monolayer. Our study shows that the absorbance of the bare α-P monolayer can be enhanced by coating with amino acid and nucleobases. The absorbance spectrum can be further modified by the adsorption of these molecules to gold atoms on the α-P monolayer.

International audience; The four main stable isotopes of the [ADy(tta)3(L)]·C6H14 (ADy with A = 161–164) Single-Molecule Magnet (SMM) (tta− = 2-thenoyltrifluoroacetylacetonate and L = 2-{[2-methylpyridiyl]-4,5-[4,5-bis(propylthio)-tetrathiafulvalenyl]-1H-benzimidazol-2-yl}pyridine) have been magnetically investigated and structurally characterized by single crystal X-ray diffraction. The two nuclear spin-free 162/164Dy behave the same from a dynamic magnetic point of view and with slower magnetic relaxation than the two pure magnetically active isotopically substituted 161/163Dy. In addition, this paper demonstrates that 161Dy and 163Dy relax differently even if they both carry I = 5/2 nuclear spin. After the release of the dipolar interactions through magnetic dilution, ([161Dy0.05Y0.95(tta)3(L)]·C6H14) (161Dy@Y) relaxes four times slower than 163Dy@Y due to different hyperfine coupling constants.

Full list of authors: Falstad, N.; Aalto, S.; König, S.; Onishi, K.; Muller, S.; Gorski, M.; Sato, M.; Stanley, F.; Combes, F.; González-Alfonso, E.; Mangum, J. G.; Evans, A. S.; Barcos-Muñoz, L.; Privon, G. C.; Linden, S. T.; Díaz-Santos, T.; Martín, S.; Sakamoto, K.; Harada, N.; Fuller, G. A.; Gallagher, J. S.; van der Werf, P. P.; Viti, S.; Greve, T. R.; García-Burillo, S.; Henkel, C.; Imanishi, M.; Izumi, T.; Nishimura, Y.; Ricci, C.; Mühle, S., Context. Some luminous and ultraluminous infrared galaxies (LIRGs and ULIRGs) host extremely compact (r < 100 pc) and dusty nuclei. The high extinction associated with large column densities of gas and dust toward these objects render them hard to detect at many wavelengths. The intense infrared radiation arising from warm dust in these sources can provide a significant fraction of the bolometric luminosity of the galaxy and is prone to excite vibrational levels of molecules such as HCN. This results in emission from the rotational transitions of vibrationally excited HCN (HCN-vib); the brightest emission is found in compact obscured nuclei (CONs; ςHCN-vib > 1 L⊙ pc-2 in the J = 3-2 transition). However, there have been no systematic searches for CONs, and it is unknown how common they are. Aims. We aim to establish how common CONs are in the local Universe (z < 0.08), and whether their prevalence depends on the luminosity or other properties of the host galaxy. Methods. We conducted an Atacama Large Millimeter/submillimeter Array survey of the rotational J = 3-2 transition of HCN-vib in a volume-limited sample of 46 far-infrared luminous galaxies. Results. Compact obscured nuclei are identified in 38-13+18% of the ULIRGs, 21-6+12% of the LIRGs, and 0-0+9% of the lower luminosity galaxies. We find no dependence on the inclination of the host galaxy, but strong evidence of lower IRAS 25 μm to 60 μm flux density ratios (f25/f60) in CONs (with the exception of one galaxy, NGC 4418) compared to the rest of the sample. Furthermore, we find that CONs have stronger silicate features (s9.7 μm), but similar polycyclic aromatic hydrocarbon equivalent widths (EQW6.2 μm) compared to other galaxies. Along with signatures of molecular inflows seen in the far-infrared in most CONs, submillimeter observations also reveal compact, often collimated, outflows. Conclusions. In the local Universe, CONs are primarily found in (U)LIRGs, in which they are remarkably common. As such systems are often highly disturbed, inclinations are difficult to estimate, and high-resolution continuum observations of the individual nuclei are required to determine if the CON phenomenon is related to the inclinations of the nuclear disks. Further studies of the in- A nd outflow properties of CONs should also be conducted to investigate how these are connected to each other and to the CON phenomenon. The lower f25/f60 ratios in CONs as well as the results for the mid-infrared diagnostics investigated (EQW6.2 μm and s9.7 μm) are consistent with the notion that large dust columns gradually shift the radiation from the hot nucleus to longer wavelengths, making the mid- A nd far-infrared "photospheres"significantly cooler than the interior regions. Finally, to assess the importance of CONs in the context of galaxy evolution, it is necessary to extend this study to higher redshifts where (U)LIRGs are more common. © 2021 ESO., This paper makes use of the following ALMA data: ADS/JAO.ALMA#2018.1.01344.S., ADS/JAO.ALMA#2015.1.00404.S, ADS/ JAO.ALMA#2017.1.00082.S, ADS/JAO.ALMA#2017.1.00057.S, ADS/JAO. ALMA#2013.1.00032.S, ADS/JAO.ALMA#2017.1.00598.S, ADS/JAO.ALMA#2015.1.00412.S. ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada), MOST and ASIAA (Taiwan), and KASI (Republic of Korea), in cooperation with the Repub lic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO and NAOJ. We acknowledge support from the Nordic ALMA Regional Centre (ARC) node based at Onsala Space Observatory. The Nordic ARC node is funded through Swedish Research Council grant No 2017-00648. S.A. gratefully acknowledges support from an ERC AdvancedGrant 789410 and from the Swedish Research Council. K.S. S.G-B. acknowledges support from the research projects PGC2018-094671-B-I00 (MCIU/AEI/FEDER, UE) and PID2019-106027GA C44 from the Spanish Ministerio de Ciencia e Innovación T.D-S. acknowledges support from the CASSACA and CONICYT fund CAS-CONICYT Call 2018. G.A.F acknowledges financial support from the State Agency for Research of the Spanish MCIU through the AYA2017-84390-C2-1-R grant (co-funded by FEDER) and through the “Center of Excellence Severo Ochoa” award for the Instituto de Astrofísica de Andalucia (SEV-2017-0709). T.R.G. acknowledges the Cosmic Dawn Center of Excellence funded by the Danish National Research Foundation under grant No. 140. E.G-A. is a Research Associate at the Harvard Smithsonian Center for Astrophysics, and thanks the Spanish Ministerio de Economía y Competitividad for support under projects ESP2017-86582-C4-1-R and PID2019-105552RB-C41. This research has made use of NASA’s Astrophysics Data System. This research has made use of the NASA/IPAC Extragalactic Database (NED) which is operated by the Jet Propulsion Labora tory, California Institute of Technology, under contract with the National Aeronautics and Space Administration.

International audience; The POCT technology involving low cost Lab-On-Chip label-free biosensing opens up an opportunity to drastically reduce the total cost of plant health and disease monitoring tools. The main requirement for a POCT tool is that it should involve relatively inexpensive equipment ensuring a sufficiently high accuracy of the plant disease early diagnostic. The principal objective of the presented work was to develop of a cost effective tool for biosensing assay, easy to use even for unskilled user. The label-free biosensing involving an optical near-field resonance phenomenon, such as Surface Plasmon Resonance (SPR) or localized surface plasmon resonance (LSPR), appears to be an appropriate approach for the above requirements. In this paper, we present a concept of multichannel biosensing platform dedicated to POCT, as well as the first proof-of-concept experimental investigations, demonstrating its practical feasibility. The instrumental platform investigated by our research group includes both disposable multichannel biochip and spectroscopic optical readout device. The proposed approach gives access to two plasmonic detection formats on the same lab-on-chip device: SPR and LSPR biosensing. In order to implement the LSPR sensing approach, our team has developed an original microfabrication method involving gold nanoparticles (Au_NPs) synthesis by pulsed laser writing. The biochip includes both microfluidic and biosensor structures formed into a single plastic slab.

We study the gravitational collapse of prestellar sources and the associated evolution of their chemical composition. We use the University of Grenoble Alpes Astrochemical Network (UGAN), which includes reactions involving the different nuclear--spin states of H2, H3+, and of the hydrides of carbon, nitrogen, oxygen, and sulfur, for reactions involving up to seven protons. In addition, species-to-species rate coefficients are provided for the ortho/para interconversion of the H3+ + H2 system and isotopic variants. The composition of the medium is followed from an initial steady state through the early phase of isothermal gravitational collapse. Both the freeze--out of the molecules on to grains and the coagulation of the grains were incorporated in the model. The predicted abundances and column densities of the spin isomers of ammonia and its deuterated forms are compared with those measured recently towards the prestellar cores H-MM1, L16293E, and Barnard B1. We find that gas--phase processes alone account satisfactorily for the observations, without recourse to grain-surface reactions. In particular, our model reproduces both the isotopologue abundance ratios and the ortho:para ratios of NH2D and NHD2 within observational uncertainties. More accurate observations are necessary to distinguish between full scrambling processes---as assumed in our gas-phase network---and direct nucleus- or atom-exchange reactions., Comment: Main paper: 18 pages; supplementary material (University of Grenoble Alpes chemical Network): 62 pages

The main purpose of this paper is to present Slovenian and Finnish prospective chemistry teachers? perceptions of their future profession, especially with regard to their understanding of the role of the triple nature of chemical concepts (macro, submicro and symbolic) and their representations in chemistry learning. A total of 19 prospective teachers (10 Slovenian, 9 Finnish) at master?s level in chemical education participated in the research. The prospective teachers? opinions were gathered using an electronic questionnaire comprising six open-ended questions. The study revealed many parallels between Slovenian and Finnish prospective chemistry teachers? perceptions of their future profession and their understanding of the role of the triple nature of chemical concepts, especially particle representations, in chemistry learning. The majority of the prospective teachers from both countries believe that personal characteristics are the most important attribute of a successful chemistry teacher. Thus, they highly value teachers? enthusiasm for teaching and the use of contemporary teaching approaches in chemistry. The prospective teachers displayed an adequate understanding of the role of the triple nature of chemical concepts (i.e., particle representations) in the planning and implementation of a specific chemistry lesson.

STIRAP (stimulated Raman adiabatic passage) is a powerful laser-based method, usually involving two photons, for efficient and selective transfer of populations between quantum states. A particularly interesting feature is the fact that the coupling between the initial and the final quantum states is via an intermediate state, even though the lifetime of the latter can be much shorter than the interaction time with the laser radiation. Nevertheless, spontaneous emission from the intermediate state is prevented by quantum interference. Maintaining the coherence between the initial and final state throughout the transfer process is crucial. STIRAP was initially developed with applications in chemical dynamics in mind. That is why the original paper of 1990 was published in The Journal of Chemical Physics. However, from about the year 2000, the unique capabilities of STIRAP and its robustness with respect to small variations in some experimental parameters stimulated many researchers to apply the scheme to a variety of other fields of physics. The successes of these efforts are documented in this collection of articles. In Part A the experimental success of STIRAP in manipulating or controlling molecules, photons, ions or even quantum systems in a solid-state environment is documented. After a brief introduction to the basic physics of STIRAP, the central role of the method in the formation of ultracold molecules is discussed, followed by a presentation of how precision experiments (measurement of the upper limit of the electric dipole moment of the electron or detecting the consequences of parity violation in chiral molecules) or chemical dynamics studies at ultralow temperatures benefit from STIRAP. Next comes the STIRAP-based control of photons in cavities followed by a group of three contributions which highlight the potential of the STIRAP concept in classical physics by presenting data on the transfer of waves (photonic, magnonic and phononic) between respective waveguides. The works on ions or ion strings discuss options for applications, e.g. in quantum information. Finally, the success of STIRAP in the controlled manipulation of quantum states in solid-state systems, which are usually hostile towards coherent processes, is presented, dealing with data storage in rare-earth ion doped crystals and in nitrogen vacancy (NV) centers or even in superconducting quantum circuits. The works on ions and those involving solid-state systems emphasize the relevance of the results for quantum information protocols. Part B deals with theoretical work, including further concepts relevant to quantum information or invoking STIRAP for the manipulation of matter waves. The subsequent articles discuss the experiments underway to demonstrate the potential of STIRAP for populating otherwise inaccessible high-lying Rydberg states of molecules, or controlling and cooling the translational motion of particles in a molecular beam or the polarization of angular-momentum states. The series of articles concludes with a more speculative application of STIRAP in nuclear physics, which, if suitable radiation fields become available, could lead to spectacular results., Journal of Physics B: Atomic, Molecular and Optical Physics, 52 (20), ISSN:1361-6455, ISSN:0368-3508, ISSN:0953-4075, ISSN:0022-3700

Exact calculation of electronic properties of molecules is a fundamental step for intelligent and rational compounds and materials design. The intrinsically graph-like and non-vectorial nature of molecular data generates a unique and challenging machine learning problem. In this paper we embrace a learning from scratch approach where the quantum mechanical electronic properties of molecules are predicted directly from the raw molecular geometry, similar to some recent works. But, unlike these previous endeavors, our study suggests a benefit from combining molecular geometry embedded in the Coulomb matrix with the atomic composition of molecules. Using the new combined features in a Bayesian regularized neural networks, our results improve well-known results from the literature on the QM7 dataset from a mean absolute error of 3.51 kcal/mol down to 3.0 kcal/mol., 28th International Conference on Artificial Neural Networks, September 17–19, 2019, Munich, Germany, Series: Lecture Notes in Computer Science; no. 11731

Metal-organic composites are of great interest for a wide range of applications. The control of their structure remains a challenge, one of the problems being a complex interplay of covalent and supramolecular interactions. This paper describes the self-assembly, thermal stability and phase transitions of ordered structures of silver atoms and thiol molecules spanning from the molecular to the mesoscopic scale. Building blocks of molecularly defined clusters formed from 44 silver atoms, each particle coated by a monolayer of 30 thiol ligands, are used as ideal building blocks. By changing solvent and temperature it is possible to tune the self-assembled 3D crystals of pristine nanoparticles or, conversely, 2D layered structures, with alternated stacks of Ag atoms and thiol monolayers. The study investigates morphological, chemical and structural stability of these materials between 25 and 300 degrees C in situ and ex situ at the nanoscale by combining optical and electronic spectroscopic and scattering techniques, scanning probe microscopies and density-functional theory (DFT) calculations. The proposed wet-chemistry approach is relatively cheap, easy to implement, and scalable, allowing the fabricated materials with tuned properties using the same building blocks.

Quartz nanopipettes have recently been employed for resistive-pulse sensing of Au nanoparticles (AuNP) and nanoparticles with bound antibodies. The analytical signal in such experiments is the change in ionic current caused by the nanoparticle translocation through the pipette orifice. This paper describes resistive-pulse detection of cancer biomarker (Vascular Endothelial Growth Factor-C, VEGF-C) through the use of antibody-modified AuNPs and nanopipettes. The main challenge was to differentiate between AuNPs with attached antibodies for VEGF-C and antigen-conjugated particles. The zeta-potentials of these types of particles are not very different, and, therefore, carefully chosen pipettes with well-characterized geometry were necessary for selective detection of VEGF-C.

The paper collects the answers of the authors to the following questions: `` What is the significance of topological approach? Can new chemical concepts be found by a topological approach? What is the status of a chemical concept within a topological approach? Should topological approaches provide measurable quantities? Is it possible to predict the outcome of a topological approach without performing a calculation on a computer? What are new domains for which topological approaches would be useful? (C) 2014 Elsevier B.V. All rights reserved.

L’objectiu de la present tesi doctoral consisteix en desenvolupar molècules policícliques de baix pes molecular que tinguin com a diana tres canals iònics específics: la viroporina A/M2 del virus de la grip, el receptor purinèrgic dependent de lligand P2X7 i el receptor glutamatèrgic dependent de lligand N-metil-D-Aspartat, per tal de modular-los d’una manera tal que n’evitin o millorin el desenvolupament dels processos patogènics associats a aquestes proteïnes i/o que permetin ser emprades com a eines de recerca. En el capítol 1 es presenta una introducció general del paper dels canals iònics, així com una descripció més específica de cadascun dels 3 canals objecte d’estudi en aquesta Tesi. Els objectius d’aquest treball es detallen en el capítol 2, després del qual, en el capítol 3 es presenten un seguit d’anàlegs per contracció d’anell del fàrmac comercial Amantadina, resultant-ne els primers inhibidors duals del canal M2 del virus de la Influenza A descrits en la bibliografia, actius sobre la soca salvatge (wt) i sobre el mutant resistent a fàrmacs V27A (Rey-Carrizo, M. et al. J. Med. Chem. 2013, 56, 9265). Seguidament en la part A del capítol 4 es gràcies a estudis in silico, s’observa com un dels inhibidors triples presenta un mode d’unió diferent sobre els canals wt i V27A, que podria estar directament relacionat amb el mecanisme de resistència a fàrmacs del mutant V27A (Rey-Carrizo, M., et al. J. Med. Chem. 2014, 57(13), 5738). En el capítol 5 es completa el treball presentant per primera vegada la proba experimental d’una possible explicació del mecanisme de resistència a fàrmacs del mutant V27A. (Barniol-Xicota, M., et al. manuscrit acceptat al J. Med. Chem.). Com a continuació en el capítol 6 s’explora una diana diferent de la viroporina M2: l’hemaglutinina (HA) (Leiva, R., et al. manuscrit pendent d’enviar a J. Med. Chem.). El capítol 7 representa el primer treball que marca l’inici de la línia de recerca d’antagonistes del receptor P2X7 en el grup. (Barniol-Xicota, M., et al. manuscrit en revisió al Bioorg. Med. Chem. Lett.). Finalment, en el capítol 8, es presenten els primers exemples descrits a la bibliografia de multi-target directed ligands (MTDL) amb els receptors NMDA i P2X7 com a dianes. (Karou, O., et al. manuscrit pendent d’enviar a ACS Med. Chem. Lett.). Deixant de banda la recerca de compostos bioactius en la part B del capítol 4 es descriu un estudi teòric i experimental d’un alquè altament piramidalitzat, derivat de l’estructura d’un compost bioactiu detallat en la part A del mateix capítol. (Rey-Carrizo, M. et al. Angew. Chem. Int. Ed. 2014, 53, 8195).

In this paper, we demonstrate an organic electrochemical transistor (OECT) based on the conductive polymer PEDOT: PSS for the analysis of the cell culture medium upon interaction with circulating cells isolated form peripheral blood sampling of health, sub-clinical and cancer patients. The device comprises arrays of super-hydrophobic micro-pillars in which a finite number of pillars incorporates nano-electrodes for site specific measurements of a solution. Due to its nano-scale architecture, the device realizes time and space resolved measurement of biological solution. Tumor metabolism could produce reactive species able to determine a different electronic behavior of correspondent microenviroment. On this basis, the device here presented the changes in the ESR signals was used to identify electronic changes occurring in the analysis of different type of microenvironment. Our results demonstrate that the device is able to register significative difference to differentiate healthy individuals form cancer patients, through an easy blood sampling. In conclusion, these preliminary data are suggestive of a novel test potentially useful to early identification of subjects at risk to development cancer disease.

This paper reports the synthesis of silica capped surfactant (cetyltrimethylammonium bromide; CTAB) and dye (Rose Bengal; RB) containing mesoporous silica nanoparticles (MSNs). Capping the pores of the surfactant containing MSNs with a thin silica layer decreased the immediate surfactant originated cytotoxicity of these particles without affecting their long term (3 days) cytotoxicity. Also, the silica capping process almost completely prevented the hemolytic activity of the surfactant containing MSNs. In addition, improved uptake of silica capped MSNs compared to the uncapped particles by cancer cells was demonstrated. The delayed cytotoxicity, low hemolytic activity, and better cellular uptake of the silica capped MSNs make them promising for the development of safe (i.e. with fewer side effects) yet efficient theranostic agents. These nanocarriers may release the loaded cytotoxic molecules (CTAB) mostly after being accumulated in the tumor site and cause so minimal damage to the normal tissues and blood components. In addition, the nanoscale confinement of RB molecules inside the pores of MSNs makes the particles brightly fluorescent. Furthermore, it was demonstrated that due to the singlet oxygen generation capability of the RB dye the silica capped MSNs can be also used for photodynamic therapy of cancer. © 2016 The Royal Society of Chemistry.

Particle-wall interactions determine in different ways the operating conditions of plasma sources, ion accelerators, and beams operating in vacuum. For instance, a contribution to gas heating is given by ion neutralization at walls; beam losses and stray particle production - detrimental for high current negative ion systems such as beam sources for fusion - are caused by collisional processes with residual gas, with the gas density profile that is determined by the scattering of neutral particles at the walls. This paper shows that Molecular Dynamics (MD) studies at the nano-scale can provide accommodation parameters for gas-wall interactions, such as the momentum accommodation coefficient and energy accommodation coefficient: in non-isothermal flows (such as the neutral gas in the accelerator, coming from the plasma source), these affect the gas density gradients and influence efficiency and losses in particular of negative ion accelerators. For ideal surfaces, the computation also provides the angular distribution of scattered particles. Classical MD method has been applied to the case of diatomic hydrogen molecules. Single collision events, against a frozen wall or a fully thermal lattice, have been simulated by using probe molecules. Different modelling approximations are compared.