bluuebunny/crossref_metadata_2025 huggingface dataset:
Phytochemical and antioxidant analysis of medicinal and food plants towards bioactive food and pharmaceutical resources
Authors: Yu Manyou , Gouvinhas Irene , Rocha João , Barros Ana I. R. N. A.
Published: May 2021

Plants with medicinal properties play an increasingly important role in food and pharmaceutical industries for their functions on disease prevention and treatment. This study characterizes the phenolic composition and antioxidant activity of seven medicinal and food plants, including the leaves of Salvia officinalis L., Rosmarinus officinalis L., Olea europaea L., and Punica granatum L., as well as the leaves and young stems of Ruta graveolens L., Mentha piperita L., and Petroselinum crispum, Mill., by using colorimetric, chromatographic, and spectrophotometric assays. Results revealed that the hydro-methanolic leaf extracts of P. granatum (pomegranate) displayed the highest content of total phenols (199.26 mg gallic acid per gram of plant dry weight), ortho-diphenols (391.76 mg gallic acid per gram of plant dry weight), and tannins (99.20 mg epicatechin per gram of plant dry weight), besides a higher content of flavonoids (24 mg catechin per gram of plant dry weight). The highest antioxidant capacity measured by ABTS, DPPH, and FRAP (2.14, 2.27, and 2.33 mM Trolox per gram of plant dry weight, respectively) methods was also obtained in pomegranate leaf extracts, being 4–200 times higher than the other species. Such potent antioxidant activity of pomegranate leaves can be ascribed to the presence of different types of phenolic compounds and the high content in tannins, whilst phenolic acids and flavonoids were found to be the dominant phenolic classes of the other six plants. Consequently, despite the well-known antioxidant properties of these plant species, our study suggests pomegranate leaf can stand out as a relatively more valuable plant source of natural bioactive molecules for developing novel functional food-pharma ingredients, with potential for not only promoting human health but also improving bio-valorization and environment.
Randomized controlled trial of convalescent plasma therapy against standard therapy in patients with severe COVID-19 disease
Authors: AlQahtani Manaf , Abdulrahman Abdulkarim , Almadani Abdulrahman , Alali Salman Yousif , Al Zamrooni Alaa Mahmood , Hejab Amal Hamza , Conroy Ronán M. , Wasif Pearl , Otoom Sameer , Atkin Stephen L. , Abduljalil Manal
Published: May 2021

Convalescent plasma (CP) therapy in COVID-19 disease may improve clinical outcome in severe disease. This pilot study was undertaken to inform feasibility and safety of further definitive studies. This was a prospective, interventional and randomized open label pilot trial in patients with severe COVID-19. Twenty COVID-19 patients received two 200 ml transfusions of convalescent patient CP over 24-h compared with 20 who received standard of care. The primary outcome was the requirement for ventilation (non-invasive or mechanical ventilation). The secondary outcomes were biochemical parameters and mortality at 28 days. The CP group were a higher risk group with higher ferritin levels (p < 0.05) though respiratory indices did not differ. The primary outcome measure was required in 6 controls and 4 patients on CP (risk ratio 0.67, 95% CI 0.22–2.0, p = 0.72); mean time on ventilation (NIV or MV) did not differ. There were no differences in secondary measures at the end of the study. Two patients died in the control and one patient in the CP arm. There were no significant differences in the primary or secondary outcome measures between CP and standard therapy, although a larger definitive study is needed for confirmation. However, the study did show that CP therapy appears to be safe in hospitalized COVID-19 patients with hypoxia.

Clinical trials registration NCT04356534: 22/04/2020.
Efficient multiscale calculation results for microchannel mass transfer
Authors: Zhang Yongbin
Published: May 2021

When the channel height is reduced to a small value such as on the scales of 10 nm or 100 nm, the physical adsorbed layers on the channel walls will participate in the flow, although intermediate between them is a continuum fluid flow. The multiscale simulation results are presented for this multiscale mass transfer in a narrow slit pore based on the derived flow equations. The results are respectively compared with those calculated from conventional continuum flow theory and from the theory based on the solid layer assumption, when the fluid-wall interaction is respectively weak, medium and strong. The total mass flow rate of the two adsorbed layers is also compared with the mass flow rate of the intermediate continuum fluid. The obtained results show the importance of the incorporation of the adsorbed layer flow by the multiscale scheme when calculating the transferred mass in a microchannel.
Genome-wide simple sequence repeats (SSR) markers discovered from whole-genome sequence comparisons of multiple spinach accessions
Authors: Bhattarai Gehendra , Shi Ainong , Kandel Devi R. , Solís-Gracia Nora , da Silva Jorge Alberto , Avila Carlos A.
Published: May 2021

The availability of well-assembled genome sequences and reduced sequencing costs have enabled the resequencing of many additional accessions in several crops, thus facilitating the rapid discovery and development of simple sequence repeat (SSR) markers. Although the genome sequence of inbred spinach line Sp75 is available, previous efforts have resulted in a limited number of useful SSR markers. Identification of additional polymorphic SSR markers will support genetics and breeding research in spinach. This study aimed to use the available genomic resources to mine and catalog a large number of polymorphic SSR markers. A search for SSR loci on six chromosome sequences of spinach line Sp75 using GMATA identified a total of 42,155 loci with repeat motifs of two to six nucleotides in the Sp75 reference genome. Whole-genome sequences (30x) of additional 21 accessions were aligned against the chromosome sequences of the reference genome and in silico genotyped using the HipSTR program by comparing and counting repeat numbers variation across the SSR loci among the accessions. The HipSTR program generated SSR genotype data were filtered for monomorphic and high missing loci, and a final set of the 5986 polymorphic SSR loci were identified. The polymorphic SSR loci were present at a density of 12.9 SSRs/Mb and were physically mapped. Out of 36 randomly selected SSR loci for validation, two failed to amplify, while the remaining were all polymorphic in a set of 48 spinach accessions from 34 countries. Genetic diversity analysis performed using the SSRs allele score data on the 48 spinach accessions showed three main population groups. This strategy to mine and develop polymorphic SSR markers by a comparative analysis of the genome sequences of multiple accessions and computational genotyping of the candidate SSR loci eliminates the need for laborious experimental screening. Our approach increased the efficiency of discovering a large set of novel polymorphic SSR markers, as demonstrated in this report.
A randomised, non-inferiority study of chloroprocaine 2% and ropivacaine 0.75% in ultrasound-guided axillary block
Authors: Sulyok Irene , Camponovo Claudio , Zotti Oliver , Haslik Werner , Köstenberger Markus , Likar Rudolf , Leuratti Chiara , Donati Elisabetta , Kimberger Oliver
Published: May 2021

Chloroprocaine is a short-acting local anaesthetic with a rapid onset of action and an anaesthesia duration up to 60 min. In this pivotal study success rates, onset and remission of motor and sensory block and safety of chloroprocaine 2% was compared to ropivacaine 0.75% for short-duration distal upper limb surgery with successful block rates as primary outcome. The study was designed as a prospective, randomised, multi-centre, active-controlled, double-blind, parallel-group, non-inferiority study, performed in 4 European hospitals with 211 patients scheduled for short duration distal upper limb surgery under axillary plexus block anaesthesia. Patients received either ultrasound guided axillary block with 20 ml chloroprocaine 2%, or with 20 ml ropivacaine 0.75%. Successful block was defined as block without any supplementation in the first 45 min calculated from the time of readiness for surgery. 90.8% patients achieved a successful block with chloroprocaine 2% and 92.9% patients with Ropivacaine 0.75%, thus non-inferiority was demonstrated (10% non inferiority margin; 95% CI − 0.097, 0.039; p = 0.02). Time to onset of block was not significantly different between the groups. Median time to motor and sensory block regression was significantly shorter as was time to home discharge (164 [155–170] min for chloroprocaine versus 380 [209–450] for the ropivacaine group, p < 0.001). For short-duration surgical procedures, the short-acting Chloroprocaine 2% may be used, with success rates non-inferior to ropivacaine and a favourable safety profile.

Trial registration: The trial was registered at Clinicaltrials.gov with registration number NCT02385097 (March 11th, 2015) and European Clinical Trial Database with the EudraCT number 2014-002519-40 (July 7th, 2015, Austria—BASG).
The fractional nonlinear $${\mathcal{PT}}$$ dimer
Authors: Molina Mario I.
Published: May 2021

We examine a fractional discrete nonlinear Schrodinger dimer, where the usual first-order derivative in the time evolution is replaced by a non integer-order derivative. The dimer is nonlinear (Kerr) and $${\mathcal{{PT}}}$$
PT
-symmetric, and for localized initial conditions we examine the exchange dynamics between both sites. By means of the Laplace transformation technique, the linear $${{\mathcal{{PT}}}}$$
PT
dimer is solved in closed form in terms of Mittag–Leffler functions, while for the nonlinear regime, we resort to numerical computations using the direct explicit Grunwald algorithm. In general, we see that the main effect of the fractional derivative is to produce a monotonically decreasing time envelope for the amplitude of the oscillatory exchange. In the presence of $${\mathcal{{PT}}}$$
PT
symmetry, the oscillations experience some amplification for gain/loss values below some threshold, while beyond threshold, the amplitudes of both sites grow unbounded. The presence of nonlinearity can arrest the unbounded growth and lead to a selftrapped state. The trapped fraction decreases as the nonlinearity is increased past a critical value, in marked contrast with the standard (non-fractional) case.
The influence of active carbon contaminants on the ozonation mechanism interpretation
Authors: Fijołek Lilla , Świetlik Joanna , Frankowski Marcin
Published: May 2021

In water treatment technology, activated carbons are used primarily as sorbents to remove organic impurities, mainly natural organic matter, but also as catalysts in the ozonation process. Commercially available activated carbons are usually contaminated with mineral substances, classified into two main groups: alkali metals (Ca, Na, K, Li, Mg) and multivalent metals (Al, Fe, Ti, Si). The presence of impurities on the carbon surface significantly affects the pHpzc values determined for raw and ozonated carbon as well as their acidity and alkalinity. The scale of the observed changes strongly depends on the pH of the ozonated system, which is related to the diffusion of impurities from the carbon to the solution. In an acidic environment (pH 2.5 in this work), the ozone molecule is relatively stable, yet active carbon causes its decomposition. This is the first report that indirectly indicates that contaminants on the surface of activated carbon (multivalent elements) contribute to the breakdown of ozone towards radicals, while the process of ozone decomposition by purified carbons does not follow the radical path in bulk solution. Carbon impurities also change the distribution of the reaction products formed by organic pollutants ozonation, which additionally confirms the radical process. The study showed that the use of unpurified activated carbon in the ozonation of succinic acid (SA) leads to the formation of a relatively large amount of oxalic acid (OA), which is a product of radical SA degradation. On the other hand, in solutions with purified carbon, the amount of OA generated is negligible.
Intravital mesoscopic fluorescence molecular tomography allows non-invasive in vivo monitoring and quantification of breast cancer growth dynamics
Authors: Ozturk Mehmet S. , Montero Marta G. , Wang Ling , Chaible Lucas M. , Jechlinger Martin , Prevedel Robert
Published: May 2021

Preclinical breast tumor models are an invaluable tool to systematically study tumor progression and treatment response, yet methods to non-invasively monitor the involved molecular and mechanistic properties under physiologically relevant conditions are limited. Here we present an intravital mesoscopic fluorescence molecular tomography (henceforth IFT) approach that is capable of tracking fluorescently labeled tumor cells in a quantitative manner inside the mammary gland of living mice. Our mesoscopic approach is entirely non-invasive and thus permits prolonged observational periods of several months. The relatively high sensitivity and spatial resolution further enable inferring the overall number of oncogene-expressing tumor cells as well as their tumor volume over the entire cycle from early tumor growth to residual disease following the treatment phase. Our IFT approach is a promising method for studying tumor growth dynamics in a quantitative and longitudinal fashion in-vivo.
TCF-ALP: a fluorescent probe for the selective detection of Staphylococcus bacteria and application in “smart” wound dressings
Authors: Gwynne Lauren , Williams George T. , Yan Kai-Cheng , Patenall Bethany L. , Gardiner Jordan E. , He Xiao-Peng , Maillard Jean-Yves , James Tony D. , Sedgwick Adam. C. , Jenkins A. Toby. A.
Published: May 2021

The optical response of an alkaline phosphatase (ALP) probe was evaluated against various bacterial species.
Adsorption process and mechanism of heavy metal ions by different components of cells, using yeast (Pichia pastoris) and Cu2+ as biosorption models
Authors: Chen Xinggang , Tian Zhuang , Cheng Haina , Xu Gang , Zhou Hongbo
Published: May 2021

The Cu2+ first bound to the outer mannan and finally entered the cytoplasm. During the whole adsorption process, the number of adsorption sites in the outer and middle cell walls was the largest, and then gradually decreased.
State-of-the-art anodes of potassium-ion batteries: synthesis, chemistry, and applications
Authors: Li Peng , Kim Hun , Kim Kwang-Ho , Kim Jaekook , Jung Hun-Gi , Sun Yang-Kook
Published: May 2021

State-of-the-art tendency, present critical issues and future opportunities of anode active materials in potassium ion batteries are systematically summarized.
3D in vitro co-culture disc for spatiotemporal image analysis of cancer–stromal cell interaction
Authors: Takahashi Haruko , Kikuchi Yutaka
Published: May 2021

A 3D in vitro cancer-stroma co-culture system, a co-culture disc, was developed for the spatiotemporal image analysis of bi-directional communication between cancer cells and surrounding stromal cell in the tumour microenvironment.
Hydroquinone/quinone electro- and photochemical interconversion in isolable polypyridylruthenium(ii) complexes
Authors: Oyama Dai , Kanno Takatoshi , Takase Tsugiko
Published: May 2021

Using redox-rich and visible light-responsive Ru complexes, quinone/hydroquinone interconversions induced by electron transfer, photoirradiation and photoswitching based on ligand substitution reactions are investigated.
Mixed functionalization strategy on indium-organic framework for multiple ion detection and H2O2 turn-on sensing
Authors: Jiang Xin , Fan Ruiqing , Zhou Xuesong , Zhu Ke , Sun Tiancheng , Zheng Xubin , Xing Kai , Chen Wei , Yang Yulin
Published: May 2021

A mixed-functionalization strategy on In-MOF realizes high sensitivity detection of heavy metal ions, anions and small molecules.
Effect of cytosine–Ag+–cytosine base pairing on the redox potential of the Ag+/Ag couple and the chemical reduction of Ag+ to Ag by tetrathiafulvalene
Authors: Dairaku Takenori , Kawai Rika , Kanaba Teppei , Ono Tetsuya , Yoshida Kentaro , Sato Hajime , Nozawa-Kumada Kanako , Kondo Yoshinori , Kondo Jiro , Ono Akira , Tanaka Yoshiyuki , Kashiwagi Yoshitomo
Published: May 2021

[Ag(cytidine)2]+ formation can be utilized for controlling the redox potential of the Ag+/Ag couple.
High performance hybrid capacitive deionization with a Ag-coated activated carbon electrode
Authors: Yoon Hongsik , Lee Jiho , Min Taijin , Lee Gunhee , Oh Minsub
Published: May 2021

Schematic of hybrid capacitive deionization with a Ag-coated activated carbon electrode illustrating the effect of Ag on the enhancement in the deionization capacity.
Physicochemical properties and digestive kinetics of whey protein gels filled with potato and whey protein mixture emulsified oil droplets: effect of protein ratios
Authors: Mao Chao , Wu Juan , Cheng Yu , Chen Tian , Ren Xiaofeng , Ma Haile
Published: May 2021

Potato protein at the surface of emulsion droplets improves the microstructure and gel properties of emulsion-filled whey protein gels, whereas it delays the digestion rate.
pH manipulates the assembly of a series of dysprosium clusters with subtle differences
Authors: Wang Hai-Ling , Liu Tong , Zhu Zhong-Hong , Peng Jin-Mei , Zou Hua-Hong , Liang Fu-Pei
Published: May 2021

This study is the first to fine-tune a series of lanthanide clusters with the same shape through pH manipulation.
Constructing a stable interface between the sulfide electrolyte and the Li metal anodeviaa Li+-conductive gel polymer interlayer
Authors: Wang Ya-Hui , Yue Junpei , Wang Wen-Peng , Chen Wan-Ping , Zhang Ying , Yang Yu-Guo , Zhang Juan , Yin Ya-Xia , Zhang Xing , Xin Sen , Guo Yu-Guo
Published: May 2021

Anin situderived Li+-conductive gel polymer interlayer enables intimate solid–solid contact and uniform Li+flux at the Li/Li10GeP2S12heterointerface and effectively inhibits interfacial reactions and Li dendrite growth.
Recent advances in the functionalization of saturated cyclic amines
Authors: He Yan , Zheng Zhi , Yang Jintao , Zhang Xinying , Fan Xuesen
Published: May 2021

Functionalized cyclic amines are the essential structural moieties of numerous biologically active compounds. This review summarized the most recent advances in the C–H, C–N and C–C bond functionalization of saturated cyclic amines.
Pressure-induced stability and polymeric nitrogen in alkaline earth metal N-rich nitrides (XN6, X = Ca, Sr and Ba): a first-principles study
Authors: Liu Zhipeng , Wei Shuli , Guo Yanhui , Sun Haiyang , Sun Hao , Chang Qiang , Sun Yuping
Published: May 2021

The Fddd-SrN6 structure can transform into P1̄-SrN6, and polymerized to infinite nitrogen chain structures at P = 22 GPa. For BaN6, the Fmmm-BaN6 structure can transform into C2/m-BaN6, and polymerized to N6 ring network structure at P = 110 GPa.
Controllable stereoinversion in DNA-catalyzed olefin cyclopropanation via cofactor modification
Authors: Hao Jingya , Miao Wenhui , Lu Shengmei , Cheng Yu , Jia Guoqing , Li Can
Published: May 2021

Cofactor modification in a DNA-catalyzed olefin cyclopropanation reaction enables controllable stereoinversion and achieves enantioselectivities of up to +91% and −72% eetrans.
Anchoring-mediated topology signature of self-assembled elastomers undergoing mechanochromic coupling/decoupling
Authors: Xing Ziyu , Lu Haibao , Fu Yong Qing
Published: May 2021

Schematic illustrations of mechanochromic coupling and topological transition in self-assembled elastomers.
In situ coating of a lithiophilic interphase on a biporous Cu scaffold with vertical microchannels for dendrite-free Li metal batteries
Authors: Wang Li-Min , Ban Xiao-Kuan , Jin Zong-Zi , Peng Ran-Ran , Chen Chu-Sheng , Chen Chun-Hua
Published: May 2021

Copper oxide is coated in situ on a phase inversion-derived Cu scaffold for Li metal anodes, which exhibit a low nucleation overpotential, high coulombic efficiency and a long lifespan. The scaffold-Li//NCM full cell exhibits good cycling stability.
Novel anti-Kasha fluorophores exhibiting dual emission with thermally activated delayed fluorescence through detouring triplet manifolds
Authors: Jhun Byung Hak , Jeong Dong Yeun , Nah Sanghee , Park Soo Young , You Youngmin
Published: May 2021

A series of donor–coumarin dyads exhibit dual emission with thermally activated delayed fluorescence which emerges from the π–π* and intramolecular charge-transfer transition states.
Steady-state enzyme kinetics
Authors: Lloyd Matthew D.
Published: May 2021

Steady-state enzyme kinetics is a cornerstone technique of biochemistry and related sciences since it allows the characterization and quantification of enzyme behaviour. Enzyme kinetics is widely used to investigate the physiological role of enzymes, determine the effects of mutations and characterize enzyme inhibitors. Well-known examples of enzyme inhibitors used to treat diseases include anti-infectives (e.g., penicillin, clavulanic acid and HIV protease inhibitors); anti-inflammatories (e.g., aspirin and ibuprofen); cholesterol-lowering statins; tyrosine kinase inhibitors used to treat cancer; and Viagra. Commonly, new disease treatments are discovered by using enzyme kinetics to identify the few active compounds residing within a large compound collection (‘high-throughput screening’).

The subject of enzyme kinetics is typically introduced to first-year undergraduates with a mathematical description of behaviour. This Beginners Guide will give a brief overview of experimental enzyme kinetics and the characterization of enzyme inhibitors. Colorimetric assays using a microtitre plate will be considered, although most principles also apply to other assays.
Equivalent subdomain method for performance prediction of permanent magnet eddy current brakes
Authors: Li Jiahao , Yang Guolai
Published: May 2021

An equivalent subdomain method for calculating the performance parameters of permanent magnet eddy current brakes (ECB) is presented by combining subdomain technology with a magnetic equivalent circuit (MEC) model. The proposed method replaces the source term in the subdomain model with an equivalent current sheet applied to the boundary of an equivalent region. The relative permeability of the equivalent region is related to design parameters rather than infinite ones and is obtained by the MEC model considering the eddy current reaction. A small prototype experimental platform is established. The validity of the proposed method is verified by the experiment and the finite element method (FEM). The results show that the braking force predicted by the method match well with those obtained by the FEM without considering the edge effect, and are slightly larger than those measured by the experiment. Considering the static edge effect, the results of the proposed method agree well with the measured values and FEM results. The method also proves to be effective in the performance prediction of the ECB with different design parameters. In addition, the limitation of the proposed method is discussed in detail.
Detection and assessment scheme of voltage and current unbalance for three phase synchronous generators using dual numerical techniques based on correlation and deviation percentage concepts
Authors: Mahmoud Ragab Abd Allah
Published: May 2021

A differentiation in three‐phase voltages or currents is termed as unbalance. Unbalance can be caused by unbalanced loads and power system faults. This disturbance results in serious problems in system elements, particularly to synchronous generators, due to the deviation of magnitude, frequency or phase shift. The ability to detect unbalance as well as to identify the severity level of unbalance is very important in power grids. This paper describes a protection scheme for voltage and current unbalance in synchronous generators. The scheme is based on dual numerical techniques application utilizing correlation and deviations percentages for voltage and current signals to detect and assess the unbalance situations. Different types of disturbances are simulated to verify the effectiveness of the proposed scheme using ATP and MATLAB programs. The simulation results prove that the scheme is successful for unbalance detection and assessment of synchronous generators. The different faults and operating conditions have no effect on the proposed scheme reliability. Also, the results show that the proposed scheme is able to classify the unbalance into different severity levels. Besides the obtained results reveal this scheme is effective and secure to the acceptable overloading and temporary faults in power systems.
Photometric redshift estimation with a convolutional neural network: NetZ
Authors: Schuldt S. , Suyu S. H. , Cañameras R. , Taubenberger S. , Meinhardt T. , Leal-Taixé L. , Hsieh B. C.
Published: May 2021

Galaxy redshifts are a key characteristic for nearly all extragalactic studies. Since spectroscopic redshifts require additional telescope and human resources, millions of galaxies are known without spectroscopic redshifts. Therefore, it is crucial to have methods for estimating the redshift of a galaxy based on its photometric properties, the so-called photo-z. We have developed NetZ, a new method using a convolutional neural network (CNN) to predict the photo-zbased on galaxy images, in contrast to previous methods that often used only the integrated photometry of galaxies without their images. We use data from the Hyper Suprime-Cam Subaru Strategic Program (HSC SSP) in five different filters as the training data. The network over the whole redshift range between 0 and 4 performs well overall and especially in the high-zrange, where it fares better than other methods on the same data. We obtained a precision |zpred − zref| ofσ = 0.12 (68% confidence interval) with a CNN working for all galaxy types averaged over all galaxies in the redshift range of 0 to ∼4. We carried out a comparison with a network trained on point-like sources, highlighting the importance of morphological information for our redshift estimation. By limiting the scope to smaller redshift ranges or to luminous red galaxies, we find a further notable improvement. We have published more than 34 million new photo-zvalues predicted with NetZ. This shows that the new method is very simple and swift in application, and, importantly, it covers a wide redshift range that is limited only by the available training data. It is broadly applicable, particularly with regard to upcoming surveys such as theRubinObservatory Legacy Survey of Space and Time, which will provide images of billions of galaxies with similar image quality as HSC. Our HSC photo-zestimates are also beneficial to theEuclidsurvey, given the overlap in the footprints of the HSC andEuclid.
The NAROO digitization center
Authors: Robert V. , Desmars J. , Lainey V. , Arlot J.-E. , Perlbarg A.-C. , Horville D. , Aboudarham J. , Etienne C. , Guérard J. , Ilovaisky S. , Khovritchev M. Y. , Le Poncin-Lafitte C. , Le Van Suu A. , Neiner C. , Pascu D. , Poirier L. , Schneider J. , Tanga P. , Valls-Gabaud D.
Published: May 2021

The New Astrometric Reduction of Old Observations (NAROO) center can be found at the Paris Observatory in Meudon, and it is dedicated to the measurement of astrophotographic plates and the analysis of old observations. The NAROO digitizer consists of a granite-based Newport-Microcontrol open-frame air-bearing XY positioning table, a scientific sCMOS camera, and a telecentric optical system. The plate holder assembly is suited for mounting glass plates up to 350 mm squared. The machine positioning stability is better than 15 nm, and its repeatability is better than 40 nm. With real photographic plate data, we were able to produce measurements with an accuracy better than 65 nm. The renewed interest about photographic plates concerns the expansion of the database of transient objects evolving in time, since digitization now makes it possible to measure images with a high level of accuracy and to identify all the available objects. The information extracted from such materials can be of an astrometric, photometric, and spectroscopic nature, when not purely imaging, with consequences in planetology, near-Earth asteroid risk assessment, astrophysical phenomena, and general relativity, to mention but a few. Through our scientific program in the Gaia era, we detail examples of current and upcoming uses for the community. We invite researchers to use our facilities and digitize their collection by answering our call for proposals.
Intermediate-size fullerenes as degradation products of interstellar polycyclic aromatic hydrocarbons
Authors: Omont A. , Bettinger H. F.
Published: May 2021

The high interstellar abundances of polycyclic aromatic hydrocarbons (PAHs) and their size distribution are the result of complex chemical processes implying dust, UV radiation, and the main gaseous components (H, C+, and O). These processes must explain the high abundance of relatively small PAHs in the diffuse interstellar medium (ISM) and imply the continuous formation of some PAHs that are small enough (number of carbon atoms NC < ~35–50) to be completely dehydrogenated by interstellar UV radiation. The carbon clusters Cn thus formed are constantly exposed to the absorption of ~10–13.6 eV UV photons, allowing isomerization and favoring the formation of the most stable isomers. They might tend to form irregular carbon cages. The frequent accretion of interstellar C+ ions could favor further cage isomerization, as is known in the laboratory for C60, possibly yielding most stable fullerenes, such as C40, C44, and C50. These fullerenes are expected to be very stable in the diffuse ISM because C2 ejection is not possible by single UV photon absorption, but could need rare two-photon absorption. It is possible that at least one of these fullerenes or its cation is as abundant as C60 or C60+ in the diffuse ISM, although this abundance is limited by the lack of observed matching features in observed mid-infrared spectra. B3LYP calculations of the visible spectrum for a number of fullerene isomers with 40 ≤NC ≤ 50 show that they generally have a few spectral bands in the visible range, with f-values in the range of a few 10−2. This could make such fullerenes interesting candidates for the carriers of some diffuse interstellar bands.
Identification of pre-stellar cores in high-mass star forming clumps via H2D+ observations with ALMA
Authors: Redaelli E. , Bovino S. , Giannetti A. , Sabatini G. , Caselli P. , Wyrowski F. , Schleicher D. R. G. , Colombo D.
Published: May 2021

Context. The different theoretical models concerning the formation of high-mass stars make distinct predictions regarding their progenitors, which are the high-mass pre-stellar cores. However, no conclusive observation of such objects has been made to date.

Aims. We aim to study the very early stages of high-mass star formation in two infrared-dark massive clumps. Our goal is to identify the core population that they harbour and to investigate their physical and chemical properties at high spatial resolution.

Methods. We obtained Atacama Large Millimeter/submillimeter Array (ALMA) Cycle 6 observations of continuum emission at 0.8 mm and of the ortho-H2D+ transition at 372 GHz towards the two clumps. We used the SCIMES algorithm to identify substructures (i.e. cores) in the position-position-velocity space, finding 16 cores. We modelled their observed spectra using a Bayesian fitting approach in the approximation of local thermodynamic equilibrium. We derived the centroid velocity, the line width, and the molecular column density maps. We also studied the correlation between the continuum and molecular data, which in general do not present the same structure.

Results. We report, for the first time, the detection of ortho-H2D+ in high-mass star-forming regions performed with an interferometer. The molecular emission shows narrow and subsonic lines, suggesting that locally, the temperature of the gas is below 10 K. From the continuum emission, we estimated the cores’ total masses and compare them with the respective virial masses. We also computed the volume density values, which are found to be higher than 106 cm−3.

Conclusions. Our data confirm that ortho-H2D+ is an ideal tracer of cold and dense gas. Interestingly, almost all the H2D+-identified cores are less massive than ≈13 M⊙, with the exception of one core in AG354, which could be as massive as 39 M⊙ under the assumption of low dust temperature (5 K). Furthermore, most of them are sub-virial and larger than their Jeans masses. These results are hence difficult to explain in the context of the turbulent accretion models, which predict massive and virialised pre-stellar cores. However, we cannot exclude that the cores are still in the process of accreting mass and that magnetic fields are providing enough support for the virialisation. ALMA could also be seeing only the innermost parts of the cores, and hence the cores’ total masses could be higher than inferred in this work. Furthermore, we note that the total masses of the investigated clumps are below the average for typical high-mass clumps, and thus studies of more massive sources are needed.
Solar wind current sheets and deHoffmann-Teller analysis
Authors: Steinvall K. , Khotyaintsev Yu. V. , Cozzani G. , Vaivads A. , Yordanova E. , Eriksson A. I. , Edberg N. J. T. , Maksimovic M. , Bale S. D. , Chust T. , Krasnoselskikh V. , Kretzschmar M. , Lorfèvre E. , Plettemeier D. , Souček J. , Steller M. , Štverák Š. , Vecchio A. , Horbury T. S. , O’Brien H. , Evans V. , Fedorov A. , Louarn P. , Génot V. , André N. , Lavraud B. , Rouillard A. P. , Owen C. J.
Published: May 2021

Context.Solar Orbiter was launched on 10 February 2020 with the purpose of investigating solar and heliospheric physics using a payload of instruments designed for both remote and in situ studies. Similar to the recently launched Parker Solar Probe, and unlike earlier missions, Solar Orbiter carries instruments designed to measure low-frequency DC electric fields.

Aims.In this paper, we assess the quality of the low-frequency DC electric field measured by the Radio and Plasma Waves instrument (RPW) on Solar Orbiter. In particular, we investigate the possibility of using Solar Orbiter’s DC electric and magnetic field data to estimate the solar wind speed.

Methods.We used a deHoffmann-Teller (HT) analysis, based on measurements of the electric and magnetic fields, to find the velocity of solar wind current sheets, which minimises a single component of the electric field. By comparing the HT velocity to the proton velocity measured by the Proton and Alpha particle Sensor (PAS), we have developed a simple model for the effective antenna length,Leffof the E-field probes. We then used the HT method to estimate the speed of the solar wind.

Results.Using the HT method, we find that the observed variations inEyare often in excellent agreement with the variations in the magnetic field. The magnitude ofEy, however, is uncertain due to the fact that theLeffdepends on the plasma environment. Here, we derive an empirical model relatingLeffto the Debye length, which we can use to improve the estimate ofEyand, consequently, the estimated solar wind speed.

Conclusions.The low-frequency electric field provided by RPW is of high quality. Using the deHoffmann-Teller analysis, Solar Orbiter’s magnetic and electric field measurements can be used to estimate the solar wind speed when plasma data are unavailable.
Numerical investigation of the fluid structure acoustics interaction on a simplified car model
Authors: Nusser Katrin , Becker Stefan
Published: May 2021

Part of vehicle interior noise is caused by the complex turbulent flow field behind the a-pillar and side mirror. It excites the structure of the side window, which radiates noise into the interior. Both aerodynamic pressure excitation and acoustic sound sources in the flow play an important role. In this work, the influence of both excitation mechanisms is investigated numerically in a hybrid simulation on a simplified car geometry. The generic model allows for an exact definition of boundary conditions and good reproducibility of simulation results. An incompressible Large-Eddy-Simulation (LES) of the flow is conducted, from which acoustic source terms within the flow field and transient fluid forces acting on the surface of the side window are extracted. This data is used in a coupled vibroacoustic and aeroacoustic simulation of the structure and passenger cabin of the vehicle. A finite element (FE) approach is used for the simulations and detailed modeling of the structure and the influence of interior absorption properties is emphasized. The computed excitation on the side window and the interior noise levels are successfully validated by using experimental data. The importance and contribution of both aerodynamic and acoustic pressure excitation to the interior sound level are determined.
Étude des difficultés conceptuelles des élèves marocains sur la formation d’image à travers une lentille convergente et la vision
Authors: Cheikh Ahmed Sidi , Ahaji Khalid , Belmoudene Ahmed
Published: May 2021

Cette recherche vise à explorer les difficultés conceptuelles lié à la formation d’image optique et la vision, chez les élèves de la deuxième année secondaire collégial ; avant et après l’enseignement ordinaire de l’optique géométrique. L’échantillon de cette étude est composé de 52 élèves, dont 22 du groupe expérimental et 30 du groupe du groupe control. Les données ont été collectes à travers un questionnaire (pré-test et posttest). Cet article a exploré quelques conceptions alternatives chez les élèves, à propos du rôle de la lentille dans la formation d’image et le processus de vision. Nous examinons, ensuite, l’effet d’une activité d’apprentissage basée sur les nouvelles technologies, sur l’évolution conceptuelle des élèves. L’analyse statistique de résultats a montré qu’il y a une différence statiquement significative, entre le résultat du groupe expérimental et le résultat du groupe contrôle. Le groupe expérimental a enregistré une amélioration significative, plus de 49%.
L’impact de l’usage du TBI sur la motivation et les résultats scolaires des élèves dans l’enseignement des mathématiques et des sciences à l’école élémentaire
Authors: Redouani Abdessamad
Published: May 2021

L’objectif de cette recherche est de mesurer l’impact de l’usage du TBI sur la motivation et les résultats scolaires des élèves dans le cadre de l’enseignement des mathématiques et des sciences à l’école élémentaire. Ce sont 121 élèves et 7 enseignants qui ont été interrogés et/ou observés pour cette recherche. Quatre instruments de collecte de données ont été utilisés: Un questionnaire d’enquête auprès des élèves, des entretiens individuels auprès des enseignants, des entretiens de groupe auprès des élèves et des observations directes en classe. Les résultats montrent que l’usage du TBI renforce la motivation et améliore les résultats scolaires des élèves en mathématiques et en sciences.
Disposition des enseignants marocains à l’adoption des ressources éducatives libres : État des lieux et perspectives
Authors: Benali Mourad , Boukare Mohammed , Elouelji Samira , Blej Mohammed
Published: May 2021

Les systèmes éducatifs à l'échelle mondiale explorent le potentiel des Ressources Educatives Libres (REL). Cependant, l’adoption des REL reste limitée chez les enseignants. Cette étude exploratoire s’appuie sur le modèle pyramidal d’adoption des REL et a pour objectif de recueillir des renseignements de base sur le niveau de connaissance et d’utilisation des REL. Un questionnaire en ligne a été mis à la disposition de 1297 enseignants marocains. Les résultats révèlent une méconnaissance du concept de REL, des sources où l’on peut les trouver et des cadres d’octroi de licences et de droits d’auteurs chez la majorité des répondants. L’inclusion de l’adoption des REL dans les modules de formation des enseignants est fortement recommandée.
Apports des TIC dans l'enseignement et l’apprentissage des mathématiques : Scénarisation pédagogique et pratiques de l'enseignement à distance
Authors: Chakri Lekbir , Riouch My Lhassan
Published: May 2021

L’intégration des TICE (technologie d’information et de communication dans l’enseignement) nécessite une réflexion profonde sur l’évolution des pratiques de classe. Elle nécessite surtout l’innovation dans le choix et dans la conception des situations des apprentissages qui utilisent d’une façon progressive et rationnelle les ressources numériques. Le choix adéquat des approches pédagogiques et didactiques de l'enseignant et des ressources numériques à utiliser ont un impact direct sur l’amélioration de la qualité des apprentissages mathématiques. Dans notre contribution nous réservons une place pour l’impact de la scénarisation et le film éducatif notamment dans l’apprentissage et l’enseignement à distance pour assurer la continuité pédagogique. Nous nous concentrons aussi sur la classe inversée et le e-learning pour leurs rôles dans l’auto-apprentissage des apprenants. Toutefois, il faut signaler que la conception de nouvelles ressources éducatives numériques et leur mise en oeuvre présentent un défi majeur pour les enseignants ; pour produire une nouvelle ressource numérique, il faut combiner les fonctionnalités de plusieurs logiciels. On parle alors des concepts liés à la genèse et l’orchestration instrumentale [1, 12].
Etude de cohérence entre aspect relationnel et satisfaction des apprenants à travers la pédagogie différenciée
Authors: Diyer Okacha , Achtaich Naceur , Najib Khalid
Published: May 2021

La pédagogie différenciée offre aux élèves l'opportunité de développer des interactions locales au sein de leurs groupes et aussi au sein du groupe-classe. Afin de réaliser les objectifs pour lesquels l'enseignant adopte une méthode qui se base sur cette pédagogie, il devra préparer les conditions préalables de sa réussite. Dans notre recherche, nous nous sommes intéressés à l'aspect relationnel qui peux exister entre les membres de chaque groupe afin de créer un environnement motivant et ambitieux. Pour mettre en évidence l'importance du critère relationnel pour une partition donnée d'une classe, nous avons modélisé cet aspect par une fonction appelée fonction relationnelle globale sur toute la classe dont sa restriction sur tout groupe est appelée fonction relationnelle locale. Pour prouver l'impact de l'aspect relationnel sur l'efficacité de l'opération d'apprentissage, nous avons aussi mis en évidence une autre fonction qui caractérise la satisfaction des élèves de la classe, appelée fonction de satisfaction globale sur toute la classe dont sa restriction sur tout groupe est appelée fonction de satisfaction locale. Nous avons étudié quelques propriétés de ces deux fonctions et ensuite nous avons mis en évidence la corrélation qui existe entre le relationnel et le rendement des apprenants dans le groupe-classe.
Eine akute Fazialisparese als mögliche Impfkomplikation bei einer Impfung gegen SARS-CoV-2
Authors: Volk Gerd Fabian , Kuttenreich Anna-Maria , Geitner Maren , Guntinas-Lichius Orlando
Published: May 2021

Obwohl die akute Fazialisparese (akute Gesichtsnervenlähmung, Bell-Lähmung) als mögliche Impfkomplikation auf eine Impfung gegen SARS-CoV-2 explizit im Aufklärungsmerkblatt der Impfstoffe erwähnt wird, überwiegt aus unserer Sicht klar der Nutzen der Impfung gegenüber möglichen Risiken. Aus den bisherigen Fallbeschreibungen lässt sich allenfalls, wenn überhaupt, ein gering erhöhtes Risiko ableiten. Das Risiko einer akuten Fazialisparese ist im Zusammenhang mit vielen Impfungen beschrieben; das Risiko scheint, wenn vorhanden, kein spezifisches Risiko zu sein. Andererseits sind auch Fälle von akuter Fazialisparese unter einer COVID-19-Erkrankung beschrieben, sodass sich die theoretische Frage stellt, inwieweit die Impfung möglicherweise eher das Auftreten einer Fazialisparese verhindert als befördert. Schlussendlich lässt sich die akute Fazialisparese, wenn schnell gehandelt wird, gut therapieren und ist von der Schwere und Folgeerscheinungen nicht mit der Krankheitsschwere und den möglichen Folgeerscheinungen einer COVID-19-Erkrankung zu vergleichen.
Surgery for Pulmonary Metastases: Long-Term Survival in 281 Patients
Authors: Dudek Wojciech , Schreiner Waldemar , Haj Khalaf Mohamed , Sirbu Horia
Published: May 2021

Background Despite weak evidence, pulmonary metastasectomy (PM) is widely performed with intent to improve patient survival. Our single-institution analysis aims to evaluate outcomes and to identify factors influencing survival of patients undergoing PM for metastases from wide range of primary tumors.

Materials and Methods All patients undergoing curative-intent PM between 2008 and 2018 were retrospectively analyzed. The impact of factors related to primary tumor, metastases, and associated therapy on overall survival (OS) was evaluated using univariable and multivariable Cox proportional hazard models. Cutoff values of continuous variables were determined by a receiver operating characteristic analysis.

Results In this study, 281 patients (178 male, median age 61 years) underwent PM. Two (0.7%) perioperative deaths and 23 (8.2%) major complications occurred. Median interval between the treatment of primary tumor and PM was 21 months. Median size of largest metastasis was 1.4 cm. After the median follow-up of 29 months, 134 patients (47.7%) had died. Five-year OS rate after first PM was 47.1%. Complete resection was achieved in 274 (97.5%) patients. Multivariable analysis identified genitourinary origin (hazard ratio [HR]: 0.30, 95% confidence interval [CI]: 0.15–0.60, p = 0.0008) as independent positive survival prognosticator; incomplete resection (HR: 3.53, 95% CI: 1.40–8.91, p = 0.0077) and age at PM of ≥66 years (HR: 1.97, 95% CI: 1.36–2.85, p = 0.0003) were negative prognosticators.

Conclusion The use of PM as a part of multimodal treatment is in selected population justified. Our analysis identified age, primary tumor origin, and completeness of resection as independent survival prognosticators.
Endoscopic-Assisted Microsurgical Resection of Right Recurrent Meckel's Cave Meningioma Extended to Cavernous Sinus
Authors: Fava Arianna , di Russo Paolo , Giammattei Lorenzo , Froelich Sébastien
Published: May 2021

Objective This study was aimed to present the complete removal of a large recurrent Meckel's cave meningioma.

Design This study is a case report.

Setting The study was conducted at Department of Neurosurgery and Skull Base Laboratory at Lariboisiére Hospital, Paris.

Participant A 53-year-old male was presented with a severe V1, V2, and V3 hypoesthesia and pain. He was operated 7 years ago for a right Meckel's cave meningioma with postoperative V1–V2 hypoesthesia. Magnetic resonance imaging (MRI) showed a large tumor recurrence extending into the cavernous sinus (CS), posterior fossa (PF), sphenoid sinus (SS), pterygopalatine (PPF), and infratemporal fossa (ITF; Fig. 1).

Main Outcome Measures Radiological results and postoperative course were assessed for this study.

Results The previous right frontotemporal approach was used. The lateral wall of the orbit, the middle fossa floor and the anterior temporal base were drilled to expose the orbit, PPF, and ITF. Foramen ovale (FO), foramen rotondum (FR), and superior orbital fissure (SOF) were opened. The meningoorbital band was cut and the lateral wall of CS was elevated (Fig. 2). The inferior orbital fissure was opened and tumor removed into the ITF, PPF, and orbit. After entering Meckel's cave from above, tumor was removed from PF. After microsurgical tumor removal, a 45-degree endoscope was used to remove tumor remnant and mucosa into SS. A watertight dural closure with pericranium was performed, reinforced with autologous fat and fibrin glue. Postoperative MRI showed complete tumor resection (Fig. 1). The patient experienced a right-side keratitis that resolved within 10 days and a V3 hypoesthesia that improved at 2 months.

Conclusion This surgical case shows how the anatomical knowledge is mandatory in skull base surgery and how the integration of microsurgical and endoscopic-assisted techniques allows to obtain optimal results.

The link to the video can be found at: https://youtu.be/qxt_389AdWU.