bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optimal scheduling of Egyptian grid with pumped storage hydroelectric power plant
Authors: Abdelhady Rameen , Abdellatif Diaa 
Published: August 2022

AbstractEgypt's national development plan aims at diversifying energy resources and expanding on renewable energy generation technologies. However, the Egyptian national grid needs energy‐storage components to stabilize its power supply when coupled with renewable energy due to the intermittent and random nature of them. The optimal power expansion plan has been reached using a production and costing software package electric generation expansion analysis system (EGEAS). Although pumped storage hydroelectric power plants (PSHPPs) have potential to be constructed in Attaqa Mountain, Egypt, it has not been considered in Egypt's optimal power expansion plan. This study proposes an optimal scheduling of Egypt's grid, adding PSHPP as a committed power plant. First, a mathematic formulation of Attaqa PSHPP is presented. Then, to reach the goal of economic dispatch, an optimal scheduling model of national grid is established with the consideration of both respective operation constraints and load requirements. The results of EGEAS simulation module showed that PSHPP operation for 20 years achieves a net fuel cost saving of 795 M$ as calculated from with and without PSHPP conditions at domestic subsidized fuel prices. More than double of this saving, 7778 M$, could be achieved if the net fuel cost savings are calculated at international fuel prices.
WLS algorithm for UAV navigation in satellite‐less environments
Authors: Santos Ricardo , Matos‐Carvalho J. P. , Tomic Slavisa , Beko Marko 
Published: August 2022

AbstractThis work addresses one of the major challenges in the field of Unmanned Aerial Vehicles (UAVs), which is related to UAV navigation in 3‐dimensional indoor environments. This topic is highly relevant due to limited‐to‐no availability of satellite signals that are usually the main sources used to govern the movement of UAVs in outdoor environments. Instead, the algorithm proposed in this work resorts to terrestrial radio measurements between the UAV and a set of stationary reference points to accomplish accurate navigation. The radio measurements are first exploited to give origin to range information that is used to calculate intersection points between a suitable subset of spheres, which serve as a coarse estimate of the UAV's position. From the intersection points, both azimuth and elevation angle estimates are obtained at each reference point. Finally, by taking advantage of estimated bearing information and applying simple geometry, the localisation problem is formulated according to the Weighted Least Squares (WLS) criterion and solved in closed form. The authors’ simulation results show good performance of the proposed approach, matching or even outperforming the state‐of‐the‐art methods in terms of localisation accuracy with significantly lower computational complexity.
Highly collimated microquasar jets as efficient cosmic-ray sources
Authors: Escobar G. J. , Pellizza L. J. , Romero G. E. 
Published: August 2022

Context. Supernova remnants (SNRs) are currently believed to be the main sites of origin for Galactic cosmic rays. This scenario, however, fails to explain some of the features observed in the cosmic-ray spectrum. Microquasars have been proposed as additional candidates, as their non-thermal emission indicates the existence of efficient particle acceleration mechanisms in their jets. Only a few initial attempts have been made so far to quantify the contribution of microquasars to the Galactic cosmic-ray population. A promising scenario envisages the production of relativistic neutrons in the jets that decay outside the system, injecting relativistic protons to the surroundings. The first investigations of this scenario suggest that microquasars might stand as a fair alternative to cosmic-ray sources.
Aims. We aim to assess the role played by the degree of collimation of the jet on the cosmic-ray energetics in the neutron-carrier scenario, as well as the location and size of the emission region and the interactions of protons with photon fields. Our goal is to explain the Galactic component of the observed proton cosmic-ray spectrum at energies higher than ∼10 GeV and to relate the aforementioned jet properties with the power and spectral index of the produced cosmic rays.
Methods. Here, we improve upon previous analytical models of relativistic particle transport in microquasar jets by including prescriptions for the jet geometry and convection within it. We introduced the neutron component through catastrophic terms that couple the proton and neutron transport equations, then we computed the escape and decay of these neutrons. Finally, we followed the propagation of the decay products and obtained the proton cosmic-ray spectrum once the particles reached the interstellar medium.
Results. We find that collimated jets, with compact acceleration regions close to the jet base, are very efficient sources that could deliver a fraction of up to ∼0.01 of their relativistic proton luminosity into cosmic rays. Collimation is the most significant feature regarding efficiency: a well-collimated jet might be four orders of magnitude more efficient than a poorly collimated one. These sources produce a steep spectral index of ∼2.3 at energies up to ∼10 TeV.
Conclusions. Single microquasars may rival SNRs with respect to the power injected to the interstellar medium through cosmic rays. The main advantage of the former is the production of a steeper spectrum than the latter that is closer to what has been observed. The predictions of our model may be used to infer the total contribution of the population of Galactic microquasars to the cosmic ray population and, therefore, to quantitatively assess their significance as cosmic-ray sources.
Particle acceleration and radiation reaction in a strongly magnetised rotating dipole
Authors: Pétri J. 
Published: August 2022

Context. Neutron stars are surrounded by ultra-relativistic particles efficiently accelerated by ultra-strong electromagnetic fields. These particles copiously emit high-energy photons through curvature, synchrotron and inverse Compton radiation. To date, however, no numerical simulations have been able to handle such extreme regimes of very high Lorentz factors and magnetic field strengths close to or even above the quantum critical limit of 4.4 × 109 T.
Aims. It is the purpose of this paper to study particle acceleration and radiation reaction damping in a rotating magnetic dipole with realistic field strengths of 105 T–1010 T typical of millisecond and young pulsars and of magnetars.
Methods. To this end, we implemented an exact analytical particle pusher including radiation reaction in the reduced Landau–Lifshitz approximation where the electromagnetic field is assumed constant in time and uniform in space during one time step integration. The position update is performed using a velocity Verlet method. We extensively tested our algorithm against time independent background electromagnetic fields like the electric drift in cross electric and magnetic fields and the magnetic drift and mirror motion in a dipole. Finally, we apply it to realistic neutron star environments.
Results. We investigated particle acceleration and the impact of radiation reaction for electrons, protons, and iron nuclei inserted around millisecond pulsars, young pulsars, and magnetars, in comparison to situations without radiation reaction. We found that the maximum Lorentz factor depends on the particle species, but only weakly on the neutron star type. Electrons reach energies up to γe ≈ 108 − 109, whereas protons reach energies up to γp ≈ 105 − 106 and iron up to γ ≈ 104 − 105. While protons and iron are not affected by radiation reaction, electrons are drastically decelerated, reducing their maximum Lorentz factor by four orders of magnitude. We also found that the radiation reaction limit trajectories agree quite well with the reduced Landau–Lifshitz approximation in almost all cases.
Tracking of magnetic helicity evolution in the inner heliosphere
Authors: Alberti T. , Narita Y. , Hadid L. Z. , Heyner D. , Milillo A. , Plainaki C. , Auster H.-U. , Richter I. 
Published: August 2022

Context. Magnetic helicity is one of the invariants in ideal magnetohydrodynamics, and its spectral evolution has a substantial amount of information to reveal the mechanism that are behind turbulence in space and astrophysical plasmas.
Aims. The goal of our study is to observationally characterize the magnetic helicity evolution in the inner heliosphere by resolving the helicity transport in a scale-wise fashion in the spectral domain.
Methods. The evolution of the magnetic helicity spectrum in the inner heliosphere was tracked using a radial alignment event achieved by Parker Solar Probe at a distance of 0.17 astronomical units (AU) from the Sun and BepiColombo at 0.58 AU with a delay of about 3.5 days.
Results. The reduced magnetic helicity resolved in the frequency domain shows three main features: (1) a coherent major peak of a highly helical component at the lowest frequency at about 5 × 10−4 Hz, (2) a damping of helicity oscillation at the intermediate frequencies from 10−3 to 10−2 Hz when observed at 0.58 AU, and (3) a coherent nonhelical component in the ion-kinetic range at frequencies of about 0.1 − 1 Hz.
Conclusions. Though limited in the frequency range, the main message from this work is that the solar wind develops into turbulence by convecting large-scale helicity components on the one hand and creating and annihilating helical wave components on the other hand. Excitation of waves can overwrite the helicity profile in the inner heliosphere. By comparing this with the typical helicity spectra at a distance of 1 AU (that is, a randomly oscillating helicity sign in the intermediate frequency range up to about 1 Hz), the helicity evolution reaches a nearly asymptotic state at the Venus orbit (about 0.7 AU) and beyond.
Les approches One Health pour faire face aux émergences: un nécessaire dialogue État-sciences-sociétés
Authors: Olive Marie-Marie , Angot Jean-Luc , Binot Aurélie , Desclaux Alice , Dombreval Loïc , Lefrançois Thierry , Lury Antoine , Paul Mathilde , Peyre Marisa , Simard Frédéric , Weinbach Jérôme , Roger François 
Published: August 2022

En mars 2021, Montpellier Université d’excellence (MUSE) et Agropolis International ont réuni des décideurs, acteurs opérationnels, représentants d’organisations internationales et scientifiques pour partager leurs expériences des approches intégrées en santé dans le cadre du concept One Health. Ces échanges intersectoriels fructueux ont croisé les points de vue et ont pointé les obstacles et les enjeux de la mise en œuvre concrète de ces approches. Les participants ont abouti à des propositions pour rendre plus efficace cette mise en œuvre et faire face aux menaces sanitaires émergentes et aux futures pandémies : coconstruire des projets intégrés avec tous les acteurs concernés (citoyens, décideurs politiques, chercheurs, services locaux) ; développer des méthodes d’évaluation de leurs impacts ; former les acteurs ; institutionnaliser et coordonner les actions du niveau local au niveau mondial.
Audiovisual intervention alleviates anxiety of patients during PET/CT imaging
Authors: Abouzian Safae , Camacho Valle , Sabaté Aida , Stefaneli Patricia , Sizova Marina , Gich Ignasi , López-Mora Diego , Duch Joan , Fernández Alejandro , Estorch Montserrat , Carrió Ignasi , Flotats Albert 
Published: August 2022

Abstract
Aim to assess if the use of an audiovisual intervention in the uptake room and/or in the scanning room, could help to reduce anxiety during [18F]FDG PET/CT imaging.
Methods We prospectively studied 120 patients referred for [18F]FDG PET/CT imaging. Patients were allocated in 4 groups of 30 patients depending on the use of the audiovisual intervention: (1) no audiovisual intervention; (2) audiovisual intervention only in the uptake room; (3) audiovisual intervention only in the scanning room; (4) audiovisual intervention in the uptake and the scanning rooms. In order to measure the anxiety levels of the patients before and after the scan, all patients answered the State-Trait Anxiety Inventory (STAI).
Results The anxiety status across typical situations on a daily basis (STAI-T) of the 4 groups of patients was comparable with no significant differences. The mean State Anxiety (STAI-S) sum-score at prescan and postscan among groups was: (1) 17.5±8.7 vs. 17.3±8.6, p=0.834; (2) 17.4±10.5 vs. 15.8±9.6, p=0.110; (3) 17.5±11.7 vs. 15.1±9.8, p= 0.013; (4) 17.4±9.7 vs. 14.9±8.1, p= 0.009. The percentage of patients with reduction of the STAI-S score among groups 1–4 was 17%, 47%, 50%, and 66%, respectively. The variation of the percentage of patients with lower scores after intervention among groups was statistically significant (p<0.001).
Conclusion Audiovisual intervention decreases anxiety levels of patients referred for PET/CT imaging. The results of our study support a beneficial effect of the audiovisual intervention and its potential to alleviate the anxiety of oncological patients who undergo a PET/CT scan.
Multidisciplinary Postoperative Care Pathway to Reduce Readmissions following Endoscopic Transsphenoidal Pituitary Surgery: Improving Quality of Patient Care
Authors: Ghiam Michael K. , Ali Ibrahim A. , Dable Cortney L. , Ayala Alejandro R. , Kargi Atil Y. , Komotar Ricardo J. , Levine Corinna G. , Sargi Zoukaa 
Published: August 2022

Abstract
Background Thirty-day unplanned readmission following endoscopic transsphenoidal pituitary surgery (ETPS) occurs in up to 14% of patients. Delayed hyponatremia is one of the most common causes, accounting for 30% of readmissions and often occurs within 1 week of surgery. The authors' prior retrospective review identified endocrinology follow-up as protective factor.
Objectives Implementation of a multidisciplinary postoperative care (POC) pathway: (1) to reduce 30-day hospital readmissions following ETPS and (2) improve inpatient and outpatient coordination of care with endocrinologist.
Methods This study is a single institution temporal cohort study of patients prior to (control cohort) and after implementation of the POC pathway (intervention cohort). The POC pathway utilized postdischarge 1 to 1.5 L/d fluid restriction, postoperative days 5 to 7 serum sodium, and endocrinology follow-up within 1 week of discharge to stratify patients into tiered hyponatremia regimens.
Results A total of 542 patients were included in the study, 409 (75%) in the control cohort and 133 (25%) in the intervention cohort. All-cause readmission was significantly reduced following implementation of the POC pathway (14 vs. 6%, p = 0.015). Coordination with endocrinologist significantly increased in the inpatient (96 vs. 83%, p < 0.001) and outpatient (77 vs. 68%, p = 0.042) settings. Patients who were not in the POC pathway had the highest risk of readmission (odds ratio: 2.5; 95% confidence interval: 1.1–5.5).
Conclusion A multidisciplinary POC pathway incorporating endocrinologist in conjunction with postdischarge weight-based fluid restriction and postoperative serum sodium levels can safely be used to reduce 30-day readmissions following ETPS.
The Awakening of a Sleeping Beauty: The ortho Photocycloaddition in the Total Synthesis of Protoilludane- and Prezizaene-Type ­Sesquiterpenes
Authors: Bach Thorsten , Gilbert Audrey 
Published: August 2022

AbstractPhotochemical cascade (domino) reactions provide a unique opportunity for the construction of complex molecular architectures. Specifically, an intramolecular ortho photocycloaddition of 7-(alkenyloxy)-indanones triggers a sequence of consecutive reactions that can lead in a single operation to the complete skeleton of two important classes of sesquiterpenes: protoilludanes and prezizaenes. In the former case, two transformations follow the initial photocycloaddition, while in the latter case, there are three consecutive transformations, two of which are initiated by a photon. Remarkably, the reaction cascades proceed with exquisite diastereoselectivity, generating three (protoilludane) or five (prezizaene) stereogenic centers with defined relative configurations.1	Introduction2	First Encounter and Initial Studies3	Protoilludane-Type Sesquiterpenes4	Prezizaene-Type Sesquiterpenes5	Enantioselectivity6	Perspective and Summary
A compound cantilever beam piezoelectric harvester based on wind energy excitation
Authors: Zhang Zheng , He Lipeng , Hu Renhui , Hu Dianbin , Zhou Jianwen , Cheng Guangming 
Published: August 2022

In this paper, a compound cantilever beam based piezoelectric energy harvester (CCBPH) is proposed. This piezoelectric energy harvester uses vibrations caused by vortex excitation behind the winding fluid to harvest wind energy. In particular, this structure uses vortex excitation formed behind a vertically suspended cylindrical winding fluid to cause the vibration of the cylindrical winding fluid, which then indirectly excites the piezoelectric element. The CCBPH consists of a fixed support, a cantilever beam, magnet-1 and magnet-2, a support beam, two piezoelectric units-PVDF (polyvinylidene fluoride), a compound cantilever beam, and a cylindrical winding fluid. We investigated the parameters affecting the structure and verify the effectiveness of the energy harvester through the design of the structure, simulation analysis, and experiments. The experimental results show that the CCBPH can obtain the maximum output voltage from the energy harvester at a wind speed of 18 m/s. The maximum output power was achieved with an external load resistance of 2000 kΩ. By comparison, it is found that the maximum output power is 0.095 mW when the distance between two magnets is 20 mm and the mass ratio is 1:2 for copper.
A new potential energy surface and rovibrational spectra of the CO–CO2 complex: Dependence on the antisymmetric stretching vibration of CO2
Authors: Peng Yang , Zhu Fangfang , Zhu Hua 
Published: August 2022

We present a new ab initio five-dimensional potential energy surface for the CO–CO2 complex containing the Q3 normal mode for the ν3 asymmetric stretching vibration of the CO2 unit. The potential was calculated by the supermolecular approach at the explicitly correlated coupled cluster [CCSD (T)-F12a] level with aug-cc-pVTZ basis set plus midpoint bond functions. Two vibrationally averaged four-dimensional potentials for CO–CO2 with CO2 at the ground and ν3 excited states were generated by the integration of the five-dimensional potential over the Q3 intramolecular coordinate. Each potential displays a T-shaped global minimum with the C end in the CO unit pointing toward the C atom in the CO2 unit and a T-shaped local minimum but with the CO monomer rotated by 180°. The rovibrational bound states and energy levels for the CO–CO2 dimer were obtained employing the radial discrete variable representation/angular finite basis representation method in conjunction with the Lanczos algorithm. The vibrational ground and some lower excited states for CO–CO2 are localized around the global minimum because of the higher potential barriers. The band origin is blueshifted by 0.2089 cm−1 for CO–CO2 in the CO2 ν3 range, which is consistent with the experimental result of 0.211 cm−1. The geared bending vibrational frequencies for CO–CO2 are 24.7101 and 24.5549 cm−1 at the ground and ν3 excited states of CO2, respectively. The predicted rovibrational frequencies, as well as spectral constants, coincide with the available observations, and these parameters show that the CO–CO2 complex is a nearly prolate asymmetric rotor.
Potential curves of the lower nine states of Li2 molecule: Accurate calculations with the free complement theory and the comparisons with the SAC/SAC-CI results
Authors: Nakatsuji Hiroshi , Nakashima Hiroyuki 
Published: August 2022

The free-complement (FC) theory proposed for solving the Schrödinger equation of atoms and molecules highly accurately was applied to the calculations of the potential curves of the lower nine states of the Li2 molecule. The results were compared with the accurate experimental Rydberg–Klein–Rees potential curves available. They overlap completely with each other without any shift everywhere for all the states of Li2. At all the calculated points on the seven potential curves ranging between −14.83 and −15.00 hartree, the average difference was only 0.0583 kcal/mol and the maximum difference was only +0.165 kcal/mol. For the vertical excitation energies from the ground state curve to the seven excited states, the differences between theory and experiment were 0.000 645 eV in average and their maximum difference was −0.007 20 eV. The potential properties calculated with the FC theory also agreed well with the experimental values. These results show a high potentiality of the FC theory as a highly predictive quantum chemistry theory. For comparison, as an example of the Hartree–Fock based theory popular in modern quantum chemistry, we adopted the symmetry-adapted-cluster (SAC)-configuration-interaction (CI) theory using a highly flexible basis set. While the FC theory gave the absolute agreements with experiments, the SAC-CI potential curves compare reasonably well with experiments only after shifting-down of the SAC-CI curves by 5.727 kcal/mol. The differences in the excitation energies between SAC-CI and experiments were 0.004 28 eV on average, and the maximum difference was +0.109 67 eV. The SAC-CI results reported in 1985 were less accurate but still reasonable.
Accurate property prediction by second order perturbation theory: The REMP and OO-REMP hybrids
Authors: Behnle Stefan , Richter Robert , Völkl Luca , Idzko Paul , Förstner André , Bozkaya Uğur , Fink Reinhold F. 
Published: August 2022

The prediction of molecular properties such as equilibrium structures or vibrational wavenumbers is a routine task in computational chemistry. If very high accuracy is required, however, the use of computationally demanding ab initio wavefunction methods is mandatory. We present property calculations utilizing Retaining the Excitation Degree – Møller–Plesset (REMP) and Orbital Optimized REMP (OO-REMP) hybrid perturbation theories, showing that with the latter approach, very accurate results are obtained at second order in perturbation theory. Specifically, equilibrium structures and harmonic vibrational wavenumbers and dipole moments of closed and open shell molecules were calculated and compared to the best available experimental results or very accurate calculations. OO-REMP is capable of predicting bond lengths of small closed and open shell molecules with an accuracy of 0.2 and 0.5 pm, respectively, often within the range of experimental uncertainty. Equilibrium harmonic vibrational wavenumbers are predicted with an accuracy better than 20 cm−1. Dipole moments of small closed and open shell molecules are reproduced with a relative error of less than 3%. Across all investigated properties, it turns out that a 20%:80% Møller–Plesset:Retaining the Excitation Degree mixing ratio consistently provides the best results. This is in line with our previous findings, featuring closed and open shell reaction energies.