bluuebunny/crossref_metadata_2025 huggingface dataset:
Ionic liquid decoration for the hole transport improvement of PEDOT
Authors: Ding Wei-Lu , Peng Xing-Liang , Sun Zhu-Zhu , Bi Kailun , Zhang Yaqin , Wang Yanlei , Ji Lin , He Hongyan
Published: February 2021

Ionic liquids (ILs) play an important role in conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) based electronics and thermoelectrics through regulating morphology and electronic properties.
Correction: When Mayo falls short (Ctr ≫ 1): the use of cumulative chain length distribution data in the determination of chain transfer constants (Ctr) for radical polymerizations
Authors: Donald Matt K. , Bon Stefan A. F.
Published: February 2021

Correction for ‘When Mayo falls short (Ctr ≫ 1): the use of cumulative chain length distribution data in the determination of chain transfer constants (Ctr) for radical polymerizations’ by Matt K. Donald and Stefan A. F. Bon, Polym. Chem., 2020, 11, 4281–4289, DOI: 10.1039/D0PY00348D.
A comparison of sizing methods for a long-term renewable hybrid system. Case study: Galapagos Islands 2031
Authors: Cano A. , Arévalo Paul , Jurado F.
Published: February 2021

This research compared different sizing methods to improve the current autonomous hybrid system in the Galapagos Islands in 2031, analyzing the loss of power supply probability (LPSP).
Improved GRAVITY astrometric accuracy from modeling optical aberrations
Authors:   GRAVITY Collaboration, Abuter R. , Amorim A. , Bauböck M. , Berger J. P. , Bonnet H. , Brandner W. , Clénet Y. , Davies R. , de Zeeuw P. T. , Dexter J. , Dallilar Y. , Drescher A. , Eckart A. , Eisenhauer F. , Förster Schreiber N. M. , Garcia P. , Gao F. , Gendron E. , Genzel R. , Gillessen S. , Habibi M. , Haubois X. , Heißel G. , Henning T. , Hippler S. , Horrobin M. , Jiménez-Rosales A. , Jochum L. , Jocou L. , Kaufer A. , Kervella P. , Lacour S. , Lapeyrère V. , Le Bouquin J.-B. , Léna P. , Lutz D. , Nowak M. , Ott T. , Paumard T. , Perraut K. , Perrin G. , Pfuhl O. , Rabien S. , Rodríguez-Coira G. , Shangguan J. , Shimizu T. , Scheithauer S. , Stadler J. , Straub O. , Straubmeier C. , Sturm E. , Tacconi L. J. , Vincent F. , von Fellenberg S. , Waisberg I. , Widmann F. , Wieprecht E. , Wiezorrek E. , Woillez J. , Yazici S. , Young A. , Zins G.
Published: February 2021

The GRAVITY instrument on the ESO VLTI pioneers the field of high-precision near-infrared interferometry by providing astrometry at the 10−100 μas level. Measurements at this high precision crucially depend on the control of systematic effects. We investigate how aberrations introduced by small optical imperfections along the path from the telescope to the detector affect the astrometry. We develop an analytical model that describes the effect of these aberrations on the measurement of complex visibilities. Our formalism accounts for pupil-plane and focal-plane aberrations, as well as for the interplay between static and turbulent aberrations, and it successfully reproduces calibration measurements of a binary star. The Galactic Center observations with GRAVITY in 2017 and 2018, when both Sgr A* and the star S2 were targeted in a single fiber pointing, are affected by these aberrations at a level lower than 0.5 mas. Removal of these effects brings the measurement in harmony with the dual-beam observations of 2019 and 2020, which are not affected by these aberrations. This also resolves the small systematic discrepancies between the derived distance R0 to the Galactic Center that were reported previously.
Les systèmes alimentaires aux défis de la crise de la Covid-19 en Afrique : enseignements et incertitudes
Authors: Dury Sandrine , Alpha Arlène , Zakhia-Rozis Nadine , Giordano Thierry
Published: February 2021

La crise liée au SARS-CoV2 (syndrome respiratoire aigu sévère–coronavirus 2) a donné lieu à une profusion de documents et webinaires sur la sécurité alimentaire au niveau international, ce qui tend à brouiller la compréhension des dynamiques à l’œuvre sur le terrain. Cet article se propose de faire le point sur la situation des secteurs agricole et agroalimentaire, à partir des informations relayées par un réseau d’experts du Cirad et de leurs partenaires dans une diversité de pays en Afrique subsaharienne. Mises en perspective avec les rapports des organisations internationales, ces informations permettent de dresser un constat nuancé. Si le commerce mondial des produits de base et la production agricole dans les pays du Sud ont été relativement peu affectés par les mesures de restriction prises pour limiter la propagation du virus, certaines filières de produits périssables ont rencontré des difficultés pour écouler leurs produits. Mais surtout, la crise a mis en exergue la déconnexion entre le monde de la production agricole, du commerce alimentaire et la situation des consommateurs précaires, qui dans les villes et dans le secteur informel ont pris de plein fouet l’arrêt des activités économiques. Cette crise sanitaire invite à repenser les mesures de gestion de la crise, tant à court terme qu’à plus long terme, avec une approche intégrée des systèmes alimentaires pour renforcer leur résilience et soutenir les stratégies d’adaptation des acteurs.
VVUQ of a thermal-hydraulic multi-scale tool on unprotected loss of flow accident in SFR reactor
Authors: Marie Nathalie , Li Simon , Marrel Amandine , Marquès Michel , Bajard Sophie , Tosello Annick , Perez Jorge , Grosjean Baptiste , Gerschenfeld Antoine , Anderhuber Marine , Geffray Chotaire , Gorsse Yannick , Mauger Gédéon , Matteo Laura
Published: February 2021

Within the framework of the French 4th-generation Sodium-cooled Fast Reactor safety assessment, methodology on VVUQ (Verification, Validation, Uncertainty Quantification) is conducted to demonstrate that the CEA's thermal-hydraulic Scientific Computation Tools (SCTs) are effective and operational for design and safety studies purposes on this type of reactor. This VVUQ-based qualification is a regulatory requirement from the French Nuclear Safety Authority (NSA). In this paper, the current practice of VVUQ approach application for a SFR accidental transient is described with regard to the NSA requirements. It constitutes the first practical, progressively improvable approach. As the SCT is qualified for a given version on a given scenario, the transient related to a total unprotected station blackout has been selected. As it is a very complex multi-scale transient, the SCT MATHYS (which is a coupling of the CATHARE2 tool at system scale, TrioMC tool at component scale and TrioCFD tool at local scale) is used. This paper presents the preliminary VVUQ application to the qualification of this tool on this selected transient. In addition, this work underlines some feedback on design and R&D aspects that should be addressed in the future to improve the SCT.
Characterisation of a cysteine protease from poultry red mites and its potential use as a vaccine for chickens
Authors: Murata Shiro , Taniguchi Ayaka , Isezaki Masayoshi , Fujisawa Sotaro , Sakai Eishi , Taneno Akira , Ichii Osamu , Ito Takuya , Maekawa Naoya , Okagawa Tomohiro , Konnai Satoru , Ohashi Kazuhiko
Published: February 2021

Poultry red mites (PRMs, Dermanyssus gallinae) are ectoparasites that negatively affect farmed chickens, leading to serious economic losses worldwide. Acaricides have been used to control PRMs in poultry houses. However, some PRMs have developed resistance to acaricides, and therefore different approaches are required to manage the problems caused by PRMs. Vaccination of chickens is one of the methods being considered to reduce the number of PRMs in poultry houses. In a previous study, a cysteine protease, Deg-CPR-1, was identified as a candidate vaccine against PRMs distributed in Europe. In this study, we investigated the characteristics of Deg-CPR-1. A phylogenetic analysis revealed that Deg-CPR-1 is closely related to the digestive cysteine proteases of other mite species, and it was classified into a cluster different from that of chicken cathepsins. Deg-CPR-1 of PRMs in Japan has an amino acid substitution compared with that of PRMs in Europe, but it showed efficacy as a vaccine, consistent with previous findings. Deg-CPR-1 exhibited cathepsin L-like enzyme activity. In addition, the Deg-CPR-1 mRNA was expressed in the midgut and in all stages of PRMs that feed on blood. These results imply that Deg-CPR-1 in the midgut may have important functions in physiological processes, and the inhibition of its expression may contribute to the efficacy of a Deg-CPR-1-based vaccine. Further research is required to fully understand the mechanisms of vaccine efficacy.
Risikoabschätzung einer akuten Exazerbation bei COPD-Patienten im Rahmen einer pneumologischen Anschluss-Rehabilitation anhand der Prävalenz und Schwergradausprägung von Komorbiditäten
Authors: Luu P. , Tulka S. , Knippschild S. , Windisch W. , Spielmanns M.
Published: February 2021

Einleitung Akute COPD-Exazerbationen (AECOPD) im Rahmen einer pneumologischen Rehabilitation (PR) sind häufige und gefährliche Komplikationen. Neben Einschränkungen der Lebensqualität führen sie zu einem Unterbrechung der PR und gefährden den PR-Erfolg. Eine Abhängigkeit zwischen dem Krankheitsstatus und einem erhöhten Risiko für eine AECOPD ist beschrieben. Dabei stellt sich die Frage, ob der Charlson Comorbidity Index (CCI) oder die Cumulative Illness Rating Scale (CIRS) dafür geeignet sind, besonders exazerbationsgefährdete COPD-Patienten in der PR im Vorfeld zu detektieren.

Patienten und Methoden In einer retrospektiven Untersuchung wurden die Daten von COPD-Patienten, welche im Jahr 2018 eine PR erhielten, analysiert. Primärer Endpunkt der Untersuchung war die Punktzahl im CCI. Alle Daten wurden dem Klinikinformationssystem Phönix entnommen und COPD-Exazerbationen erfasst. Die laut Fallzahlplanung benötigten 44 Patienten wurden zufällig (mittels Zufallsliste für jede Gruppe) aus diesem Datenpool rekrutiert: 22 Patienten mit und 22 ohne Exazerbation während der PR. CCI und CIRS wurden für die eingeschlossenen Fälle für beide Gruppen bestimmt. Die Auswertung des primären Endpunktes (CCI) erfolgte durch den Gruppenvergleich der arithmetischen Mittel und der Signifikanzprüfung (Welch-Tests). Weitere statistische Lage- und Streuungsmaße wurden ergänzt (Median, Quartile, Standardabweichung).

Zusätzlich wurde mittels Receiver Operating Characteristic (ROC)-Analyse sowohl für den CCI als auch für den CIRS ein optimaler Cutpoint zur Diskriminierung in AECOPD- und Nicht-AECOPD-Patienten gesucht.

Ergebnisse 244 COPD-Patienten erhielten eine stationäre PR von durchschnittlich 21 Tagen, wovon 59 (24 %) während der PR eine behandlungspflichtige AECOPD erlitten. Die ausgewählten 22 Patienten mit einer AECOPD hatten einen mittleren CCI von 6,77 (SD: 1,97) und die 22 Patienten ohne AECOPD von 4,32 (SD: 1,17). Die Differenz von –2,45 war zu einem Signifikanzniveau von 5 % statistisch signifikant (p < 0,001; 95 %-KI: [–3,45 ; –1,46]). Die ROC-Analyse zeigte einen optimalen Cutpoint für den CCI bei 6 mit einer Sensitivität zur Feststellung einer AECOPD von 81,8 % und einer Spezifität von 86.,4 % mit einem Wert der AUC (area under the curve) von 0,87. Der optimale Cutpoint für den CIRS war 19 mit einer Sensitivität von 50 %, einer Spezifität von 77,2 % und einer AUC von 0,65.

Schlussfolgerung COPD-Patienten mit einer akuten Exazerbation während der pneumologischen Rehabilitation haben einen höheren CCI. Mithilfe des CCI lässt sich mit einer hohen Sensitivität und Spezifität das Risiko einer AECOPD von COPD-Patienten im Rahmen eines stationären PR-Programms einschätzen.
Anomalía de la unión biliopancreática: una entidad infrecuente en Occidente
Authors: López Grove Roy , Aineseder Martina , Ossana María Jimena , Spina Juan Carlos
Published: February 2021

La anomalía de la unión biliopancreática (AUBP) es una malformación congénita en la que los conductos pancreáticos y biliares se unen anatómicamente fuera de la pared duodenal. Debido a la excesiva longitud del canal común, la acción del esfínter no afecta la unión pancreatobiliar, lo que permite el reflujo del jugo pancreático hacia la vía biliar. Se asocia con quistes del colédoco y sus manifestaciones incluyen cáncer de la vía biliar, pancreatitis, coledocolitiasis y colangitis. Es una rara patología, especialmente en países occidentales.

La colangiopancreatografía por resonancia magnética (CPRM) se ha convertido en el método más utilizado por no ser invasivo, teniendo en cuenta que la colangiopancreatografía retrógrada endoscópica (CPRE) se encuentra contraindicada en casos de pancreatitis aguda y colangitis, además del riesgo de pancreatitis posterior al procedimiento.

La distancia entre la unión biliopancreática y la pared duodenal debe ser superior a 9 mm de longitud para diagnosticar AUBP mediante CPRM. En caso de que mida entre 6 y 9 mm y la acción del esfínter afecte la unión pancreatobiliar, se lo denomina unión biliopancreática alta (UBPA) y se debe confirmar mediante CPRE.

Describimos los hallazgos en imágenes de siete pacientes jóvenes con clínica abdominal y diagnóstico de AUBP o UBPA por CPRM, y además revisamos la literatura sobre el tema.
El lado menos dulce de la diabetes. Revisión pictográfica de las alteraciones más frecuentes en el pie diabético
Authors: Rodríguez Gabriela , Kunstmann Andrés , Jara Pablo , Gaete Cristóbal , Schiappacasse Giancarlo
Published: February 2021

La prevalencia global de diabetes mellitus (DM) aumenta cada año y, con ella, sus complicaciones. La afección del pie relacionada con DM se ha convertido en una de las principales causas de morbilidad y discapacidad. Los hallazgos más frecuentes son las alteraciones cutáneas y musculares, la arterioesclerosis y el edema óseo. Las complicaciones son la osteomielitis y la neuroartropatía, siendo causas importantes de amputación. El estudio imagenológico se inicia con radiografía (Rx), que permite descartar anomalías óseas y articulares, presencia de cuerpos extraños o alteraciones del tejido blando. Después de la Rx, la resonancia magnética (RM) es la modalidad de elección para la evaluación de la osteomielitis e infección de tejidos blandos del pie. Aunque esas afecciones comparten algunas características clínicas y de imagen con otros trastornos, el conocimiento de sus hallazgos distintivos permite al radiólogo contribuir al diagnóstico oportuno y correcto, con el fin de proporcionar al clínico información adecuada.
Infección Urinaria en Gestantes: Prevalencia y Factores Asociados en el Eje Cafetero, Colombia, 2018-2019
Authors: De La Hoz Franklin José Espitia
Published: February 2021

Objetivo estimar la prevalencia y etiología de las infecciones urinarias en gestantes del Eje Cafetero, así como describir los factores asociados e identificar la sensibilidad a los antibióticos.

Métodos estudio de corte transversal, en gestantes que consultaron, por primera vez, a consulta prenatal, y que tuvieron un resultado positivo en el urocultivo, en tres centros de atención en el Eje Cafetero, entre 2018 y 2019. Se reclutaron 1131 mujeres. Se evaluaron los factores de riesgo asociados, el aislamiento e identificación de los gérmenes involucrados, así como la prevalencia de enterobacterias productoras de β-lactamasas de espectro extendido (BLEE).

Resultados La edad de las mujeres osciló entre 18 y 42 años, promedio de 29,46 ± 5,82 años. La prevalencia global de infección urinaria fue de un 14,94% (IC95%: 11,78-21,46). La etiología más frecuente caracterizó la Escherichia Coli (80,47%), seguida por Klebsiella spp. (9,46%) y Proteus mirabilis (5,91%). La prevalencia de gérmenes BLEE (+) alcanzó el 11,24% (IC95%: 9,47-11,75). Las mujeres con depilación íntima tuvieron mayor riesgo de presentar infección urinaria (OR = 4,62; IC95%: 1,08-8,64) seguida por el tabaquismo (OR = 4,56; IC95%: 2,58-9,81) y la diabetes mellitus (OR = 3,96; IC95%: 1,05-6,54). El uso de protectores íntimos fue mayor en las mujeres con infección urinaria (OR = 2,88; IC95%: 1,02-3,99).

Conclusiones se identificó la infección urinaria en el 14,94% de las gestantes. Se detectó la Escherichia Coli como la etiología más frecuente. La depilación íntima fue el principal factor de riesgo.
Treatment of Pediatric Sternotomy Wound Complications: A Minimally Invasive Approach
Authors: Jo Taehee , Hur Joon , Kim Eun Key
Published: February 2021

Background Pediatric sternal wound complications (SWCs) include sterile wound dehiscence (SWD) and superficial/deep sternal wound infections (SSWI/DSWI), and are generally managed by repetitive debridement and surgical wound approximation. Here, we report a novel nonsurgical management strategy of pediatric sternotomy wound complications, using serial noninvasive wound approximation technique combined with single-use negative pressure wound therapy (PICO) device.

Methods Nine children with SWCs were managed by serial approximation with adhesive skin tapes and serial PICO device application. Thorough surgical debridement or surgical approximations were not performed.

Results Three patients were clinically diagnosed as SWD, two patients as SSWI, and four patients as DSWI. None of the wounds demonstrated apparent mediastinitis or bone destructions. PICO device was applied at 16.1 days (range: 6–26 days) postoperatively, together with serial wound approximation by skin tapes. The average duration of PICO use was 16.9 days (range: 11–29 days) and the wound approximation was achieved in all patients. None of the patients underwent aggressive surgical debridement or invasive surgical approximation by sutures.

Conclusion We report our successful management of selected pediatric SWCs, using serial noninvasive wound approximation technique combined with PICO device.
First principles investigation of structural, electronic, and room temperature ferromagnetism in V doped hexagonal pristine graphene
Authors: Hailemariam Sintayehu Mekonnen , Enna Akililu Esayas
Published: February 2021

The structural, electronic, and magnetic properties of V doped graphene were investigated using density functional theory. The formation energy calculation indicates that V doped graphene is stable and the V atoms are strongly hybridized with C atoms. The present study revealed that the bandgap of graphene is open in the presence of the V dopant. Moreover, the obtained magnetic moment and analysis of total density of states show that V doped graphene displays ferromagnetism. The calculated ferromagnetic transition temperature (Tc) value for a V concentration of 6.25% is 377 K. The findings are avenues to enhance the application of graphene for spintronics.
Experimental study on the structural stability of zeolite imidazolate framework-8 in the alkaline solution
Authors: Huang Zixuan , Li Hai , Liu Bei , Jia Chongzhi , Chen Wan , Yang Lanying , Chen Guangjin
Published: February 2021

In our previous work, we observed that the structure of zeolite imidazolate framework-8 (ZIF-8) decomposed in the presence of water during the CO2 capture process. However, the structure of ZIF-8 was perfectly retained after adding 5 wt. % or more 2-methylimidazole (HMeim) into the solution. In this work, we investigated the pore structural stability of ZIF-8 when it was suspended in five other alkaline solutions. The results show that the ZIF-8 suspended in monoethanolamine (MEA), methyldiethanolamine (MDEA), and HMeim can still maintain the topological structure whereas the ZIF-8 converted to ZIF-61 and Zn2(Bim)4, respectively, when it came into contact with imidazole (Him) and benzimidazole (HBim). In addition, MEA, MDEA, and HMeim solutions could protect the porous structure of ZIF-8 when ZIF-8 slurry was used for CO2 capture. Nevertheless, the structure of ZIF-8 also collapsed when the concentration of alkaline was lower than 10 wt. %.
Ab initio investigation of the CO–N2 quantum scattering: The collisional perturbation of the pure rotational R(0) line in CO
Authors: Jóźwiak Hubert , Thibault Franck , Cybulski Hubert , Wcisło Piotr
Published: February 2021

We report fully quantum calculations of the collisional perturbation of a molecular line for a system that is relevant for Earth’s atmosphere. We consider the N2-perturbed pure rotational R(0) line in CO. The results agree well with the available experimental data. This work constitutes a significant step toward populating the spectroscopic databases with ab initio collisional line-shape parameters for atmosphere-relevant systems. The calculations were performed using three different recently reported potential energy surfaces (PESs). We conclude that all three PESs lead to practically the same values of the pressure broadening coefficients.
Cage production and laying hen welfare
Authors: Hemsworth Paul H.
Published: February 2021

Although many factors affect the welfare of hens housed in cage and non-cage systems, welfare issues in cage systems often involve behavioural restrictions, whereas many welfare issues in non-cage systems involve health and hygiene. This review considers and compares the welfare of laying hens in cages, both conventional and furnished cages, with that of hens in non-cage systems, so as to highlight the welfare implications, both positive and negative, of cage housing. Comparisons of housing systems, particularly in commercial settings, are complex because of potentially confounding differences in physical, climatic and social environments, genetics, nutrition and management. Furthermore, some of the confounding factors are inherent to some specific housing systems. Nevertheless, research in commercial and experimental settings has indicated that hens in conventional and furnished cages have lower (or similar), but not higher, levels of stress on the basis of glucocorticoid concentrations than do hens in non-cage systems. Furthermore, caged hens, generally, have lower mortality rates than do hens in non-cage systems. However, the behavioural repertoire of laying hens housed in conventional cages is clearly more compromised than that of hens in non-cage systems. In contrast to conventional cages, furnished cages may provide opportunities for positive emotional experiences arising from perching, dust-bathing, foraging and nesting in a nest box. Some have suggested that the problems with modern animal production is not that the animals are unable to perform certain behavioural opportunities, but that they are unable to fill the extra time available with limited behaviours when they have no need to find food, water or shelter. Environmental enrichment in which objects or situations are presented that act successfully, and with a foreseeable rewarding outcome for hens by also providing regular positive emotional experience, is likely to enhance hen welfare. Research on cage systems highlights the importance of the design of the housing system rather than just the housing system per se.
Variability as a better characterization of Shannon entropy
Authors: Carcassi Gabriele , Aidala Christine A , Barbour Julian
Published: February 2021

The Shannon entropy, one of the cornerstones of information theory, is widely used in physics, particularly in statistical mechanics. Yet its characterization and connection to physics remain vague, leaving ample room for misconceptions and misunderstanding. We will show that the Shannon entropy can be fully understood as measuring the variability of the elements within a given distribution: it characterizes how much variation can be found within a collection of objects. We will see that it is the only indicator that is continuous and linear, that it quantifies the number of yes/no questions (i.e. bits) that are needed to identify an element within the distribution, and we will see how applying this concept to statistical mechanics in different ways leads to the Boltzmann, Gibbs and von Neumann entropies.
Total least squares problems on infinite dimensional spaces
Authors: Contino Maximiliano , Fongi Guillermina , Maestripieri Alejandra , Muro Santiago
Published: February 2021

We study weighted total least squares problems on infinite dimensional spaces. We present some necessary and sufficient conditions for the regularized problem to have a solution. The existence of solution can also be assured for the regularized minimization problem with a constraint to special subsets. Furthermore, we show that a regularization in infinite dimensional total least squares problems is necessary, since in most cases the problem without regularization does not admit a solution.
Reply to comment on ‘The 5d → 6p photoabsorption spectra of Pb II and Bi III: evidence of excited states’ by A. N. Ryabtsev
Authors: Lu Hu , Varvarezos Lazaros , Alli Muhammad Bilal , Nicolosi Piergiorgio , Costello John T , Hayden Patrick
Published: February 2021

In this reply, we address the comments made by A N Ryabtsev on our paper (H Lu et al 2020 J. Phys. B: At. Mol. Opt. Phys.
53 115001). Specifically, we emphasize that the observed spectra depend critically on the plasma source type and conditions that pertain in the source. Our source of ions and experimental setup/method are quite different to the one referred to in the comment (A N Ryabtsev et al 2000 Opt. Spectrosc.
88 316–20). So there is no doubt that our spectra contain evidence of photoabsorption from low-lying excited states, and their inclusion is necessary, in order to account for the observed spectral distributions.
Conversion between microwave and optical photons through atom–phonon hybrid modes in a waveguide-QED structure
Authors: Cao M S , Jia W Z
Published: February 2021

We present an approach to achieve bi-directional conversion between microwave and optical photons based on a hybrid waveguide-QED structure. The proposed converter combines both the merits of optomechanical system and superconducting circuits. Through analysis, we obtain two different impedance matching conditions to realize an ideal conversion efficiency close to unity. One of the matching conditions is owing to atom–phonon hybrid modes, which is different from the well known one due to dark modes. The underlying physical mechanism is discussed in detail. The performance of the setup under different matching conditions is also compared. The device studied here may be realizable in the future experiments, suitable for on-chip integrations, and may have potential applications in the future quantum networks.
Miniaturized tri-band bandpass filter design using quarter-wavelength shunted-line stepped-impedance resonators (SLSIRs) with multi-transmission zeros
Authors: Wang Ruolin , Zuo Tao , Liu Haiwen
Published: February 2021

In this paper, a miniaturized tri-band bandpass filter (BPF) is proposed with a pair of quarter-wavelength shunted-line stepped-impedance resonators (SLSIRs). The resonant characteristics, high design freedom and tuning relationship of multi-dimension parameters of SLSIR are studied and applied to the tri-band design. To obtain the great enhancement of skirt slope, multi-transmission zeros (multi-TZs) are introduced below and above the passbands and the selectivity is improved significantly. The miniaturization of subwavelength and electric/magnetic coupling are introduced and the propagation of electromagnetic wave is manipulated. Moreover, different kinds of generation mechanisms of the produced five TZs are investigated, illustrated and classified. Based on the multi-path transmission of signal, self-coupling effect and self-resonance of feed lines, the multi-TZs are excited and produced. The electric/magnetic coupling and current density distributions are plotted and analyzed. For validation, the designed second-order tri-band BPF centered at 2.35/4.89/7.42 GHz is fabricated and measured. Good agreement between the measured multi-band performances and the simulated frequency responses are observed and can be used to verify the feasibility of design concept.
Resource-efficient adaptive Bayesian tracking of magnetic fields with a quantum sensor
Authors: Craigie K , Gauger E M , Altmann Y , Bonato C
Published: February 2021

Single-spin quantum sensors, for example based on nitrogen-vacancy centres in diamond, provide nanoscale mapping of magnetic fields. In applications where the magnetic field may be changing rapidly, total sensing time is crucial and must be minimised. Bayesian estimation and adaptive experiment optimisation can speed up the sensing process by reducing the number of measurements required. These protocols consist of computing and updating the probability distribution of the magnetic field based on measurement outcomes and of determining optimized acquisition settings for the next measurement. However, the computational steps feeding into the measurement settings of the next iteration must be performed quickly enough to allow real-time updates. This article addresses the issue of computational speed by implementing an approximate Bayesian estimation technique, where probability distributions are approximated by a finite sum of Gaussian functions. Given that only three parameters are required to fully describe a Gaussian density, we find that in many cases, the magnetic field probability distribution can be described by fewer than ten parameters, achieving a reduction in computation time by factor 10 compared to existing approaches. For

T

2

*

=
1

μ
s

, only a small decrease in computation time is achieved. However, in these regimes, the proposed Gaussian protocol outperforms the existing one in tracking accuracy.
Significant magneto-elastic coupling at Griffiths-like phase boundaries in low dimensional oxides, ASb2O6 (A
= Ni and Mn)
Authors: Chatterjee A , Indra A , Gutowski O , Zimmerman M v , Majumdar S , Giri S
Published: February 2021

The compounds, NiSb2O6 (NSO) and MnSb2O6 (MSO) attract the community for the quasi one-dimensional and layered structure composed of Ni2+ and Mn2+, which orders antiferromagnetically at T
N = 6.7 and 12 K, respectively. Here, we report the Griffiths-like phase much above T
N in the range of 37–85 K and 25–80 K for NSO and MSO, respectively. The dc magnetization results indicate the Griffiths-like phase, following the modified Curie–Weiss law. The magneto-capacitive responses for both the compounds show anomalies at the onset of the Griffiths-like phase. Intriguingly, the low temperature synchrotron diffraction results are conclusive for determining the singularities for both the compounds. Interplay between the low-dimensionality, magnetic frustration, and magneto-elastic coupling correlates the observed short range ordered state, which is suggested as a Griffiths-like phase, above T
N for both the compounds.
Hard x-ray methods for studying the structure of amorphous thin films and bulk glassy oxides
Authors: Benmore C J , González G B , Alderman O L G , Wilke S K , Yarger J L , Leinenweber K , Weber J K R
Published: February 2021

High-energy photon diffraction minimizes many of the corrections associated with laboratory x-ray diffractometers, and enables structure factor measurements to be made over a wide range of momentum transfers. The method edges us closer toward an ideal experiment, in which coordination numbers can be extracted without knowledge of the sample density. Three case studies are presented that demonstrate new hard x-ray methods for studying the structure of glassy and amorphous materials. First, the methodology and analysis of high-energy grazing incidence on thin films is discussed for the case of amorphous In2O3. The connectivity of irregular InO6 polyhedra are shown to exist in face-, edge- and corner-shared configurations in the approximate ratio of 1:2:3. Secondly, the technique of high-energy small and wide angle scattering has been carried out on laser heated and aerodynamically levitated samples of silica-rich barium silicate (20BaO:80SiO2), from the single phase melt at 1500 oC to the phase separated glass at room temperature. Based on Ba–O coordination numbers of 6 to 7, it is argued that the although the potential of Ba is ionic, it is weak enough to cause the liquid–liquid immiscibility to become metastable. Lastly, high-energy small and wide angle scattering has also been applied to high water content (up to 12 wt.%) samples of hydrous SiO2 glass quenched from 1500 oC at 4 GPa. An increase of Si1–O2 correlations at 4.3 Å is found to be consistent with an increase in the population of three-membered SiO4 rings at the expense of larger rings.
Research into a novel surface acoustic wave sensor signal-processing system based on compressive sensing and an observed-signal augmentation method based on secondary information prediction
Authors: Han Wei , Bu Xiongzhu , Song Meiqiu , Huang Xinhao
Published: February 2021

Due to their unique advantages, surface acoustic wave (SAW) sensors have attracted various disciplines to carry out thorough research. However, in their wireless applications, their high carrier frequency, low signal-to-noise ratio, and short effective signal length have led to poor signal measurement accuracy and complex detection systems. Using an SAW torque sensor as its objective, this paper describes the proposal and completion of a novel processing system based on compressive sensing (CS). The system was implemented using an analog-to-information conversion module. The module hardware’s structural parameters and signal recovery parameters were designed and optimized by simulation. Furthermore, an intervening interpolation method based on support vector machine (SVM) signal secondary information prediction was developed to achieve an effective extension of the observed signal. The method’s parameters and the SVM super parameters were optimized by a cuckoo search algorithm. The success rate of the predicted signal secondary information reached more than 94%. The compression ratio of the system reached 5.77‰ while ensuring successful signal frequency recovery. Finally, a torque static calibration experiment was carried out using the system prototype; the results show that the system sensitivity is 1.951 kHz Nm−1, which proves that the scheme and methods are effective. The SAW signal-processing system based on CS combines the advantages of traditional demodulation system solutions with low hardware costs, low data volume, and high interference immunity. This system will prompt some new thoughts about SAW sensor signal detection.
Photocatalytic activity and photoelectrochemical properties of Ag/ZnO core/shell nanorods under low-intensity white light irradiation
Authors: Kadhim M J , Mahdi M A , Hassan J J , Al-Asadi Ahmed S
Published: February 2021

Zinc oxide (ZnO) nanorod thin films were prepared by CBD onto glass and FTO/glass substrates. Silver (Ag) nanoparticles were synthesized on the surface of the prepared ZnO nanorod thin films using electrochemical methods. The scanning electron microscopy images of the Ag/ZnO/glass core/shell nanostructure confirmed that the average particles size is 20 nm while it was 41 nm for Ag NPs that synthesized onto ZnO/FTO NRs. The photocatalytic activity of the prepared Ag/ZnO core/shell nanostructure was studied by analyzing the degradation of methylene blue (MB) dye under visible light. Various pH values (6 and 10) and exposure time (30–240) min were controlled to investigate the photocatalytic activity of as-prepared Ag/ZnO core/shell nanostructure and that annealed at 200 °C and 300 °C for 1 h. It was observed that when the pH was 6, the degradation rate increased with the annealing temperature and irradiation time reaching 51% at the annealing temperature of 300 °C and exposure time of 240 min. In other hands, when the pH was 10, and the sample was annealed at 200 °C, it showed a good degradation rate of 100% at the irradiation time of 90 min. By contrast, the sample annealed at 300 °C required 180 min to degrade the MB dye completely. The photoelectrochemical cell measurement based on photocurrent density revealed a slight response to light. Cycle voltammetry (CV) measurement was conducted, and the CV curves of the Ag/ZnO core/shell electrodes indicated nonfaradaic and pseudocapacitance behavior. The electrodes showed nearly rectangular CV curves, which indicated the dominance of the nonfaradaic capacitance behavior. The specific capacitance of the electrodes remained at approximately 99%. Mott–Schottky analysis revealed that the semiconductor was an n-type with dependence on flat band potential V
FB deviation in the negative direction.
Fluence-modulated proton CT optimized with patient-specific dose and variance objectives for proton dose calculation
Authors: Dickmann J , Kamp F , Hillbrand M , Corradini S , Belka C , Schulte R W , Parodi K , Dedes G , Landry G
Published: February 2021

Particle therapy treatment planning requires accurate volumetric maps of the relative stopping power, which can directly be acquired using proton computed tomography (pCT). With fluence-modulated pCT (FMpCT) imaging fluence is concentrated in a region-of-interest (ROI), which can be the vicinity of the treatment beam path, and imaging dose is reduced elsewhere. In this work we present a novel optimization algorithm for FMpCT which, for the first time, calculates modulated imaging fluences for joint imaging dose and image variance objectives. Thereby, image quality is maintained in the ROI to ensure accurate calculations of the treatment dose, and imaging dose is minimized outside the ROI with stronger minimization penalties given to imaging organs-at-risk. The optimization requires an initial scan at uniform fluence or a previous x-ray CT scan. We simulated and optimized FMpCT images for three pediatric patients with tumors in the head region. We verified that the target image variance inside the ROI was achieved and demonstrated imaging dose reductions outside of the ROI of 74% on average, reducing the imaging dose from 1.2 to 0.3 mGy. Such dose savings are expected to be relevant compared to the therapeutic dose outside of the treatment field. Treatment doses were re-calculated on the FMpCT images and compared to treatment doses re-recalculated on uniform fluence pCT scans using a 1% criterion. Passing rates were above 98.3% for all patients. Passing rates comparing FMpCT treatment doses to the ground truth treatment dose were above 88.5% for all patients. Evaluation of the proton range with a 1 mm criterion resulted in passing rates above 97.5% (FMpCT/pCT) and 95.3% (FMpCT/ground truth). Jointly optimized fluence-modulated pCT images can be used for proton dose calculation maintaining the full dosimetric accuracy of pCT but reducing the required imaging dose considerably by three quarters. This may allow for daily imaging during particle therapy ensuring a safe and accurate delivery of the therapeutic dose and avoiding excess dose from imaging.
Nonstationary coupling between heart rate and perfusion index in extremely preterm infants in the first day of life
Authors: O’Toole J M , Dempsey E M , Van Laere D
Published: February 2021

Objective. Adaptation to the extra-uterine environment presents many challenges for infants born less than 28 weeks of gestation. Quantitative analysis of readily available physiological signals at the cotside could provide valuable information during this critical time. We aim to assess the time-varying coupling between heart rate (HR) and perfusion index (PI) over the first 24 h after birth and relate this coupling to gestational age (GA), inotropic therapy, and short-term clinical outcome. Approach. We develop new nonstationary measures of coupling to summarise both frequency- and direction-dependent coupling. These measures employ a coherence measure capable of measuring time-varying Granger casuality using a short-time information partial-directed coherence function. Measures are correlated with GA, inotropic therapy (yes/no), and outcome (adverse/normal). Main results. In a cohort of 99 extremely preterm infants (<28 weeks of gestation), we find weak but significant coupling in both the HR → PI and PI → HR directions (P < 0.05). HR → PI coupling increases with maturation (correlation r = 0.26; P = 0.011). PI → HR coupling increases with inotrope administration (r = 0.27; P = 0.007). And nonstationary features of PI → HR coupling are associated with adverse outcome (r = 0.27; P = 0.009). Significance. Nonstationary features are necessary to distinguish different coupling types for complex biomedical systems. Time-varying directional coupling between PI and HR provides objective and independent biomarkers of adverse outcome in extremely preterm infants.
Nonlocal effects in negative triangularity TCV plasmas
Authors: Merlo G , Huang Z , Marini C , Brunner S , Coda S , Hatch D , Jarema D , Jenko F , Sauter O , Villard L
Published: February 2021

Global gradient driven gyrokinetic simulations performed with the Gyrokinetic Electromagnetic Numerical Experiment (GENE) code are used to investigate Tokamak à configuration variable (TCV) plasmas with negative triangularity. Considering limited L-mode plasmas, the numerical results are able to reproduce the actual transport level over a major fraction of the plasma minor radius for a plasma with

δ

LCFS

=
−
0.3

and its equivalent with standard positive triangularity δ. For the same heat flux, a larger electron temperature gradient is sustained by

δ
<
0

, in turn resulting in an improved electron energy confinement. In agreement with the experiments, a reduction of the electron density fluctuations is also seen. Local flux-tube simulations are used to gauge the magnitude of nonlocal effects. Surprisingly, very little differences are found between local and global approaches for

δ
>
0

, while local results yield a strong overestimation of the heat fluxes when

δ
<
0

. Despite the high sensitivity of the turbulence level with respect to the input parameters, global effects appear to play a crucial role in the negative triangularity plasma and must be retained to reconcile simulations and experiments. Finally, a general stabilizing effect of negative triangularity, reducing fluxes and fluctuations by a factor dependent on the actual profiles, is recovered.
Comprehensive study of physical properties of cadmium telluride thin films: effect of post-deposition high annealing temperature
Authors: Hasani Ebrahim , Raoufi Davood
Published: February 2021

Thin films of cadmium telluride (CdTe) with a thickness of 550 nm were prepared using the thermal evaporation method. The resulting films were annealed in air atmosphere at 200 °C, 300 °C, 400 °C and 500 °C. The annealed films were subjected to x-ray diffraction (XRD), micro-Raman spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), ultraviolet-visible spectroscopy and transverse current–voltage (I–V) test analyses to investigate the structural, surface morphological, optical and electrical properties of films, respectively. The XRD patterns reveal the zinc blende structure of the pristine and treated film with the preferred (111) orientation. In addition, the crystallite size increases with the rise in annealing temperature. The Raman spectra reveal a redshift with annealing as well as the formation of Te precipitates in CdTe films. The SEM images show the uniformity and homogeneity of the as-prepared films. The AFM studies show an increase in the surface roughness of the annealed films. The optical energy band gap is found to decrease with the annealing temperature. The I–V measurement indicates the ohmic behavior of CdTe films. The experimental results indicate that the annealed CdTe thin films at 400 °C have optimized physical properties for solar cell applications as an absorber layer.
Optical and structural properties of AlN thin films deposited on different faces of sapphire substrates
Authors: Yin Junhua , Zhou Bangdi , Li Liang , Liu Yao , Guo Wei , Talwar Devki N , He Kaiyan , Ferguson Ian T , Wan Lingyu , Feng Zhe Chuan
Published: February 2021

We report the comprehensive spectroscopic results of AlN thin films deposited on the A-, R- and C-surfaces of sapphire substrates by radio frequency magnetron sputtering. The optical and structural properties of the epitaxial-grown AlN films were characterized using various techniques of high-resolution x-ray diffraction spectroscopy, x-ray photoelectron spectroscopy, Raman scattering spectroscopy, spectroscopic ellipsometry and associated analytical tools. Our large number of measurement results clearly show that sapphire substrates of different polarities have effects on the surface roughness, dislocation density, grain size, microstrain, and surface oxygen binding capacity of the film grown on its surface. The results obtained from Ellipsometry measurements show that the thickness, band gap and roughness of AlN films grown on C-plane sapphire are the smallest among the three samples. After careful analyses of the variable temperature Raman spectra, as the temperature rises from 80 K to 800 K, the AlN film has always exhibited tensile stress. In the same temperature range, the tensile stress of the AlN film grown on the C-plane sapphire has the greatest effect with temperature. The lifetime of E2 (high) phonons gradually decays with the increase of temperature.
A paper fortune teller-inspired reconfigurable soft pneumatic gripper
Authors: Chen Rui , Zhang Chen , Sun Yi , Yu Tao , Shen Xin-Ming , Yuan Ze-An , Guo Jiang-Long
Published: February 2021

Soft pneumatic grippers (SPGs) have shown great grasping performances for various objects due to their simplicity, adaptability and rapid response. However, there are few SPGs that can grasp both flat and non-planar targets robustly. A reconfigurable mechanism that can transform the gripper into different states for grasping varied objects is desired by such versatile SPGs. Paper fortune teller (PFT) is a distinctive origami with 2D/3D shape switchability and 3D shape reconfigurability. In this paper, we propose a novel reconfigurable SPG which is inspired from PFT and augmented with an indirect vacuum adhesion (IVA) mechanism. The resultant gripper can not only lift flat-surface objects such as a piece of square glass (278 g) with the IVA force in its pad shape, but also pick up non-planar objects such as an orange (151 g) in a traditional grasping way in its four-converging-fingered shape. The experimental results reveal that our gripper can produce a maximum IVA force of about 4.24 N on acrylic plates and a maximum pulling force of about 2.10 N on 3D-printed non-planar objects respectively. The gripper’s traditional grasping robustness is also demonstrated when non-planar objects are placed irregularly (allowing up to 55 mm multi-orientation offsets or 20° multi-orientation drift angles). This new SPG design realizes the multi-function nature of origami transformation and is expected to promote the application of origami and soft gripper technologies.
Enhancement in the critical current density of BaTiO3-doped YBCO films by low-energy (60 keV) proton irradiation
Authors: Huang Daxing , Gu Hongwei , Shang Hongjing , Li Taiguang , Xie Bowei , Zou Qi , Chen Di , Chu Wei-kan , Ding Fazhu
Published: February 2021

Although YBa2Cu3O72212δ (YBCO) is one of the most promising superconducting materials for power applications, the fabrication of low-cost coated conductors with the high in-field performance remains challenging. Here, we report an efficient mixed-pinning landscape for enhancing the in-field performance of BaTiO3 (BTO)-doped YBCO films by low-energy (60 keV) proton irradiation. The smaller (2–4 nm), weaker but perhaps denser pinning sites have been successfully introduced by irradiation, which can form a mixed-pinning landscape with pre-doped BTO precipitates (5–15 nm), leading to the increased vortex pinning. In this case, the critical current density (J
c) of YBCO films increases significantly, especially at low temperature and high magnetic field, and it increases three times near 6 T at 20 K when the irradiation dose is 1 × 1015 proton cm−2. Additionally, the c-axis length (c-parameter) of YBCO increases with the increase of irradiation dose, which indicates the decreasing oxygen content due to the excessive irradiation, thereby the reduction in critical transition temperature (T
c). Employing low irradiation energy is beneficial for protons to stop inside YBCO film and thereby induces higher density defects when applying low doses. This fabrication technique is a practicable post-production solution to improve the in-field performance of nanoparticle-doped YBCO films.