From Au-Thiolate Chains to Thioether Sierpiński Triangles: The Versatile Surface Chemistry of 1,3,5-Tris(4-Mercaptophenyl)Benzene on Au(111)

Self-assembly of 1,3,5-tris(4-mercaptophenyl)benzene (TMB) – a three-fold symmetric, thiol functionalized aromatic molecule – was studied on Au(111) with the aim to realize extended Au-thiolate linked molecular architectures. The focus lay on resolving thermally activated structural and chemical changes by a combination of microscopy and spectroscopy. Thereby Scanning Tunneling Microscopy provided submolecularly resolved structural information, while the chemical state of sulfur was assessed by X-ray Photoelectron Spectroscopy. Directly after room temperature deposition only less well ordered structures were observed. Mild annealing promoted the first structural transition into ordered molecular chains, partly organized in homochiral molecular braids. Further annealing led to self-similar Sierpiński triangles, while annealing at even higher temperatures again resulted in mostly disordered structures. Both the irregular aggregates observed at room temperature and the chains were identified as metal-organic assemblies, whereby two out of the three intermolecular binding motifs are energetically equivalent according to Density Functional Theory simulations. The emergence of Sierpiński triangles is driven by a chemical transformation, i.e. the conversion of coordinative Au-thiolate to covalent thioether linkages, and can be further understood by Monte Carlo simulations. The great structural variance of TMB on Au(111) can on one hand be explained by the energetic equivalence of two binding motifs. On the other hand, the unexpected chemical transition even enhances the structural variance and results in thiol-derived covalent molecular architectures

Optimum Concentration of InSb Photodiode for Minimum Low Reverse Bias Leakage Current

We have investigated a relation between the impurity concentration and the leakage current for three types of InSb diodes. They were fabricated with different impurity concentrations on both sides of the junction such as p - n, p^+ - n; and p^+ - n+ in order to achieve the minimal level of noise. It is shown that the leakage current at a low reverse bias has a minimum for the p^+ - n diode structure (impurity concentration of order of 2х10^15 cm^-3 for the n-type and 1х10^18 cm^-3 for the p-type). Increasing the impurity beyond these values may cause the tunneling at a low reverse bias voltage close to zero, and decreasing the impurity causes increasing the diffusion current.Дослiджено зв’язок мiж концентрацiєю домiшки та струму витоку для трьох типiв InSb дiодiв. Дiоди було виготовлено з рiзними концентрацiями домiшки на обох боках перехода, а саме p - n, p^+ - n та p^+ - n^+; щоб отримати найнижчий рiвень шумiв. Показано, що струм витоку має мiнiмальне значення при низьких зворотних напругах змiщення для p^+ - n структури (концентрацiя домiшки порядку 2 х 10^15 cм^-3 для n-типу та 1 х 10^18 cм^-3 для p-типу). Зростання концентрацiї домiшки понад цих значень може викликати тунелювання при малих зворотних напругах змiщення, тодi як при зменшеннi концентрацiї зростає дифузiйний струм

Additively manufactured multi-morphology bone-like porous scaffolds: experiments and micro-computed tomography-based finite element modeling approaches

Tissue engineering, whose aim is to repair or replace damaged tissues by combining the principle of biomaterials and cell transplantation, is one of the most important and interdisciplinary fields of regenerative medicine. Despite remarkable progress, there are still some limitations in the tissue engineering field, among which designing and manufacturing suitable scaffolds. With the advent of additive manufacturing (AM), a breakthrough happened in the production of complex geometries. In this vein, AM has enhanced the field of bioprinting in generating biomimicking organs or artificial tissues possessing the required porous graded structure. In this study, triply periodic minimal surface structures, suitable to manufacture scaffolds mimicking bone's heterogeneous nature, have been studied experimentally and numerically; the influence of the printing direction and printing material has been investigated. Various multi-morphology scaffolds, including gyroid, diamond, and I-graph and wrapped package graph (I-WP), with different transitional zone, have been three-dimensional (3D) printed and tested under compression. Further, a micro-computed tomography (µCT) analysis has been employed to obtain the real geometry of printed scaffolds. Finite element analyses have been also performed and compared with experimental results. Finally, the scaffolds' behavior under complex loading has been investigated based on the combination of µCT and finite element modeling

Determination of normal ranges of regional and global phase parameters using gated myocardial perfusion imaging with Cedars-Sinai's QGS software

Introduction: Myocardial perfusion imaging using gated SPECT and phase analysis is an effective tool in evaluation of mechanical dyssynchrony. The purpose of this study was to determine the normal ranges of global and regional phase parameters. Methods: A total of 100 patients with normal resting and stress electrocardiograms, low pretest likelihood for coronary artery disease and a normal gated MPI study were recruited in the study. All of the patients underwent a standard 2-day stress/rest gated MPI study according to standard protocols. The reconstructed images were further analyzed by Cedar-Sinai's quantitative gated SPECT. Left ventricular phase indices were provided both globally and regionally for both genders and the normal interquartile range of these parameters were defined. Results: Normal ranges of global and wall-based regional phase parameters are presented both in unisex and in gender-specific formats. Both global (P<0.001) and major LV regional phase parameters (P<0.05) are found to be significantly different between the two genders with a significant positive association between end-diastolic volume with phase global indices (P<0.01). There is also more synchronized phase distribution in phase analysis results of post-exercise gated MPI as compared to the phase analysis of the same patients at resting state. Conclusion: Normal ranges of phase indices are defined in this article by using Cedar-Sinai's QGS software. As normal ranges of phase dyssynchrony parameters are gender-specific and are related to LV volume, stress or resting state and stress type, the need for careful incorporation of these data is indicated in interpretation of phase studies. © 2018 Tehran University of Medical Sciences. All rights reserved

Quantum gravity phenomenology at the dawn of the multi-messenger era-A review

The exploration of the universe has recently entered a new era thanks to the multi-messenger paradigm, characterized by a continuous increase in the quantity and quality of experimental data that is obtained by the detection of the various cosmic messengers (photons, neutrinos, cosmic rays and gravitational waves) from numerous origins. They give us information about their sources in the universe and the properties of the intergalactic medium. Moreover, multi-messenger astronomy opens up the possibility to search for phenomenological signatures of quantum gravity. On the one hand, the most energetic events allow us to test our physical theories at energy regimes which are not directly accessible in accelerators; on the other hand, tiny effects in the propagation of very high energy particles could be amplified by cosmological distances. After decades of merely theoretical investigations, the possibility of obtaining phenomenological indications of Planck-scale effects is a revolutionary step in the quest for a quantum theory of gravity, but it requires cooperation between different communities of physicists (both theoretical and experimental). This review, prepared within the COST Action CA18108 "Quantum gravity phenomenology in the multi-messenger approach", is aimed at promoting this cooperation by giving a state-of-the art account of the interdisciplinary expertise that is needed in the effective search of quantum gravity footprints in the production, propagation and detection of cosmic messengers. (C) 2022 The Authors. Published by Elsevier B.V.Peer reviewe

Quantum gravity phenomenology at the dawn of the multi-messenger era—A review

The exploration of the universe has recently entered a new era thanks to the multi-messenger paradigm, characterized by a continuous increase in the quantity and quality of experimental data that is obtained by the detection of the various cosmic messengers (photons, neutrinos, cosmic rays and gravitational waves) from numerous origins. They give us information about their sources in the universe and the properties of the intergalactic medium. Moreover, multi-messenger astronomy opens up the possibility to search for phenomenological signatures of quantum gravity. On the one hand, the most energetic events allow us to test our physical theories at energy regimes which are not directly accessible in accelerators; on the other hand, tiny effects in the propagation of very high energy particles could be amplified by cosmological distances. After decades of merely theoretical investigations, the possibility of obtaining phenomenological indications of Planck-scale effects is a revolutionary step in the quest for a quantum theory of gravity, but it requires cooperation between different communities of physicists (both theoretical and experimental). This review, prepared within the COST Action CA18108 “Quantum gravity phenomenology in the multi-messenger approach”, is aimed at promoting this cooperation by giving a state-of-the art account of the interdisciplinary expertise that is needed in the effective search of quantum gravity footprints in the production, propagation and detection of cosmic messengers.publishedVersio

Safety and efficacy of Favipiravir in moderate to severe SARS-CoV-2 pneumonia

Background: We examined the safety and efficacy of a treatment protocol containing Favipiravir for the treatment of SARS-CoV-2. Methods: We did a multicenter randomized open-labeled clinical trial on moderate to severe cases infections of SARS-CoV-2. Patients with typical ground glass appearance on chest computerized tomography scan (CT scan) and oxygen saturation (SpO2) of less than 93 were enrolled. They were randomly allocated into Favipiravir (1.6 gr loading, 1.8 gr daily) and Lopinavir/Ritonavir (800/200 mg daily) treatment regimens in addition to standard care. In-hospital mortality, ICU admission, intubation, time to clinical recovery, changes in daily SpO2 after 5 min discontinuation of supplemental oxygen, and length of hospital stay were quantified and compared in the two groups. Results: 380 patients were randomly allocated into Favipiravir (1 9 3) and Lopinavir/Ritonavir (1 8 7) groups in 13 centers. The number of deaths, intubations, and ICU admissions were not significantly different (26, 27, 31 and 21, 17, 25 respectively). Mean hospital stay was also not different (7.9 days SD = 6 in the Favipiravir and 8.1 SD = 6.5 days in Lopinavir/Ritonavir groups) (p = 0.61). Time to clinical recovery in the Favipiravir group was similar to Lopinavir/Ritonavir group (HR = 0.94, 95% CI 0.75 � 1.17) and likewise the changes in the daily SpO2 after discontinuation of supplemental oxygen (p = 0.46) Conclusion: Adding Favipiravir to the treatment protocol did not reduce the number of ICU admissions or intubations or In-hospital mortality compared to Lopinavir/Ritonavir regimen. It also did not shorten time to clinical recovery and length of hospital stay. © 2021 Elsevier B.V

Quantum gravity phenomenology at the dawn of the multi-messenger era -- A review

The exploration of the universe has recently entered a new era thanks to the multi-messenger paradigm, characterized by a continuous increase in the quantity and quality of experimental data that is obtained by the detection of the various cosmic messengers (photons, neutrinos, cosmic rays and gravitational waves) from numerous origins. They give us information about their sources in the universe and the properties of the intergalactic medium. Moreover, multi-messenger astronomy opens up the possibility to search for phenomenological signatures of quantum gravity. On the one hand, the most energetic events allow us to test our physical theories at energy regimes which are not directly accessible in accelerators; on the other hand, tiny effects in the propagation of very high energy particles could be amplified by cosmological distances. After decades of merely theoretical investigations, the possibility of obtaining phenomenological indications of Planck-scale effects is a revolutionary step in the quest for a quantum theory of gravity, but it requires cooperation between different communities of physicists (both theoretical and experimental). This review is aimed at promoting this cooperation by giving a state-of-the art account of the interdisciplinary expertise that is needed in the effective search of quantum gravity footprints in the production, propagation and detection of cosmic messengers

Cosmology with the Laser Interferometer Space Antenna

The Laser Interferometer Space Antenna (LISA) has two scientific objectives of cosmological focus: to probe the expansion rate of the universe, and to understand stochastic gravitational-wave backgrounds and their implications for early universe and particle physics, from the MeV to the Planck scale. However, the range of potential cosmological applications of gravitational wave observations extends well beyond these two objectives. This publication presents a summary of the state of the art in LISA cosmology, theory and methods, and identifies new opportunities to use gravitational wave observations by LISA to probe the universe