bluuebunny/crossref_metadata_2025 huggingface dataset:
Évolution des interrogatives partielles directes en français : le cas de combien
Authors: Benzitoun Christophe
Published: May 2022

Les interrogatives ont donné lieu à un grand nombre de travaux en français, tant en diachronie qu’en synchronie. Cependant, ces études ne sont pas toujours comparables à cause des données prises en compte ou des catégories retenues. C’est la raison pour laquelle nous nous proposons de relancer le travail de description grâce aux corpus désormais disponibles. Dans cet article, nous nous intéressons à l’interrogatif combien et nous montrons qu’il présente une grande diversité de fonctionnements eu égard aux types de données étudiées.
Koloskopievorbereitung bei Patienten mit Diabetes mellitus:
Entwicklung einer Handlungsempfehlung
Authors: Adamek Henning Ernst , Bergmann Laura , Müssig Karsten
Published: May 2022

Hintergrund Der Schlüsselfaktor für die Aussagekraft einer Koloskopie ist die Qualität der Darmvorbereitung (Kolonlavage). Eine schlechte Darmvorbereitung führt zu verlängerten Untersuchungszeiten, inkompletten Untersuchungen und erhöht das Komplikationsrisiko. Eine Diabeteserkrankung ist ein bedeutender Risikofaktor für eine insuffiziente Kolonlavage. Standardisierte Empfehlungen zur Koloskopievorbereitung von Diabetespatienten liegen bisher nicht vor.

Methode Es erfolgte eine selektive Literatursuche in PubMed und GoogleScholar bis einschließlich 06/2021. Leitlinien und Positionspapiere der deutschen, europäischen und amerikanischen Fachgesellschaften sowie klinikeigene Erfahrungen wurden ebenfalls berücksichtigt.

Ergebnisse Für die Darmvorbereitung gibt es verschiedene Wirkstoffe, die in 2 Hauptgruppen aufgeteilt werden können: Polyethylenglycol (PEG)-Lösungen und osmotische Lösungen. Es liegen inzwischen eine Reihe von Metaanalysen vor, die Unterschiede in den verschiedenen Vorbereitungsschemata untersucht haben. Die Ergebnisse sind sehr heterogen. Neben der Wahl des Abführmittels und der Frage welcher Zeitpunkt der Einnahme günstig ist, scheint die Art der Aufklärung zur Darmvorbereitung eine entscheidende Rolle zu spielen. Außerdem ist bei Diabetes-Patienten die Ernährung in den Tagen vor der Koloskopie von besonderer Bedeutung.

Schlussfolgerung PEG-basierte Abführlösungen in Split-Dosis sind bei Diabetes-Patienten aufgrund der häufig vorliegenden Motilitätsstörungen zu bevorzugen. Eine subtile Aufklärung über die Abführmaßnahmen und ein individueller Ernährungsplan für die Tage vor der Koloskopie werden empfohlen.
Die Arthroskopie des oberen Sprunggelenkes – Möglichkeiten und Grenzen
Authors: Gaulke Ralph
Published: May 2022

Die Arthroskopie des oberen Sprunggelenkes hat, aufgrund der kleinen Zugänge und der guten Übersichtlichkeit sämtlicher Gelenkkompartimente in Bezug auf die Synovialektomie, die Entfernung von Schleimhautfalten, insbesondere unter der Syndesmose, aber auch bei der dorsalen Synovialektomie, die offenen Verfahren weitgehend abgelöst. Neben der totalen Synovialektomie über Zugänge von dorsal und ventral ist es möglich, Osteophyten abzutragen und dadurch die Gelenkbeweglichkeit zu verbessern. Darüber hinaus können freie Gelenkkörper entfernt und Knorpelläsionen geglättet werden. Auch die arthroskopisch assistierte perkutane Schraubenarthrodese entwickelt sich zunehmend zu einem Standardverfahren in der Therapie des rheumatischen und degenerativ veränderten oberen Sprunggelenkes. Ist eine Tenosynovialektomie erforderlich, so wird auch das Gelenk offen therapiert, da das arthroskopische Vorgehen dann kaum Vorteile bietet.
The Extended Superficial Musculoaponeurotic System Deep Plane Facelift
Authors: Hu Shirley , Perkins Stephen W.
Published: May 2022

Over the past four decades, the senior author has evolved and perfected his preferred method for face and neck lifting, the extended superficial musculoaponeurotic system deep plane rhytidectomy, and submentoplasty. With this procedure, the superficial musculoaponeurotic system layer is addressed both in the face and neck, repositioning the tissues in a superior and posterior vector and creating a sling in the cervicomental area. Outcomes have proven to be both successful and long lasting. In this article, a detailed update and discussion of the specific techniques utilized are provided.
Indian female Twitter influencers’ perceptions of trolls
Authors: Pillai Varsha , Ghosh Munmun
Published: May 2022

Social media interactions invariably include trolling, where disruptive or annoying comments are made online, and gender trolling is one aspect of trolling. Gender trolling in India has turned ugly, with mischievous and offensive tweets transforming into threats. However, far too little research has examined the perceptions of such trolling among women. What do Indian women on Twitter feel about trolling? Are they encountering prejudice on the platform as well? How do they cope with vitriolic trolls and online threats? This study employs a feminist narrative approach to evaluate perceptions of gender trolling among women on Twitter in India. The study aims to understand the impact of online trolling among Indian women Twitter influencers. Insights into their online trolling experiences from twenty-five selected women social media influencers on Twitter were gathered through detailed interviews. This study unravelled some critical observations and responses towards gender trolling among women Twitter influencers in India. The research also explored if the regularization of misogynistic laced gender trolling within the Indian online space alters the way women social media influencers respond to trolling.
Chemical bonds and weak interactions of methoxysalicylic acid isomers investigated by terahertz spectroscopy and density functional theory
Authors: Tang Yuan , Li Zhi , Zhang Huo , Tu Shan , She Yulai
Published: May 2022

The characteristic absorption spectra of isomers (3-, 4-, and 6-methoxysalicylic acid) were investigated by terahertz time-domain spectroscopy (THz-TDS) in the range of 0.4–3.0 THz. In parallel with the experimental study, the unit cells of the three isomers were calculated by density functional theory, and we found that the theoretical spectral absorption peaks were basically consistent with the experimental results. To better comprehensively interpret the origin of the characteristic absorption peaks, the potential energy distribution (PED) method was used to assign the vibrational modes of absorption peaks. The interaction of the system was analyzed qualitatively and quantitatively by using the interaction region indicator (IRI) and energy decomposition analysis based on forcefield (EDA-FF). The analysis indicated the weak interaction types of 3-, 4-, and 6-methoxysalicylic acid were dominated by van der Waals interaction. There are slight differences in intra- and inter-molecular weak hydrogen bonds among the three substances. The weak interaction is mainly contributed by dispersion. The results show that THz-TDS can accurately identify isomers. It provides a novel idea for studying molecular vibration characteristics, chemical bonds, and weak interactions combined with PED, IRI, and EDA-FF analysis methods.
Improving signal-to-noise ratio of magnetic tunnel junction based radio frequency detector via spin-torque ferromagnetic resonance
Authors: Tiwari Dhananjay
Published: May 2022

This article focuses on the spin-torque ferromagnetic resonance (STFMR) technique, which was developed and optimized to investigate spin-transfer effects in magnetic tunnel junctions (MTJ) and spin Hall effect phenomena in ferromagnet/non-magnetic heavy metal bilayer systems. The devices for STFMR are typically fabricated with co-planar waveguides with contact pads for applying radio frequency or direct current, Irf(Idc). The device under investigation was a CoFeB/MgO/CoFeB based MTJ with a resistance-area product of 1.5 Ω (μm)2 having a circular cross section with a diameter of 180 nm and tunneling magneto-resistance in the range of 60%–80%. The development of the STFMR setup and its optimization for achieving higher signal-to-noise ratio (SNR) is discussed using two modulation schemes, namely, radio-frequency modulation and field modulation (FM). The FM-STFMR method reduces frequency-dependent noise and offers a higher SNR of 30 dB compared to other modulation schemes in the literature. In addition, a vector network analyzer based STFMR technique is developed, which provides a simple and fast means for characterizing MTJ devices. Furthermore, to calculate the exact power reaching the MTJ, impedance mismatch is calculated using the de-embedding method. The magnitude of in-plane torkance and out-of-plane torkance with dc bias is measured, and the results are found to be consistent with the results of STFMR techniques. The results show that the magnitude of out-of-plane torkance is substantially smaller than that of in-plane torkance in MTJ.

At the request of the authors, this article is being retracted effective 6 September 2022.
Quantum Gaussian process model of potential energy surface for a polyatomic molecule
Authors: Dai J. , Krems R. V.
Published: May 2022

With gates of a quantum computer designed to encode multi-dimensional vectors, projections of quantum computer states onto specific qubit states can produce kernels of reproducing kernel Hilbert spaces. We show that quantum kernels obtained with a fixed ansatz implementable on current quantum computers can be used for accurate regression models of global potential energy surfaces (PESs) for polyatomic molecules. To obtain accurate regression models, we apply Bayesian optimization to maximize marginal likelihood by varying the parameters of the quantum gates. This yields Gaussian process models with quantum kernels. We illustrate the effect of qubit entanglement in the quantum kernels and explore the generalization performance of quantum Gaussian processes by extrapolating global six-dimensional PESs in the energy domain.
Effect of injected flux and current temporal phasing on self-organization in the HIT-SI3 experiment
Authors: Morgan K. D. , Hansen C. J. , Hossack A. C. , Sutherland D. A.
Published: May 2022

The HIT-SI3 device at the University of Washington uses three oscillating inductive helicity injectors to form and sustain spheromak plasma equilibria. By adjusting the temporal phase of the injector waveforms with respect to each other, the toroidal spectrum of the imposed perturbations can be controlled. Using a recently implemented GPU-based control system, the available mode spectra were explored experimentally by scanning the space of relative injector phasing. In this space, significant variation in the toroidal mode spectrum (n = 1, 2, 3) of the perturbations was observed. Additionally, variation in characteristics of driven equilibria was also observed, including a ≈30% range in toroidal current gain (Iϕ/IInj). Experimental results are compared with both a composite-equilibria and nonlinear dynamic model, including extended MHD simulations using the NIMROD code and composite Taylor state equilibria computed using the PSI-Tet code. Qualitative agreement is seen with the nonlinear models, but not with composite-equilibria models, suggesting the use of nonlinear models to better capture observed plasma dynamics and provide predictive use for future experiments.
Dynamics of droplet impact on a superhydrophobic disk
Authors: Moghtadernejad Sara , Jadidi Mehdi , Hanson Jack , Johnson Zachary
Published: May 2022

An experimental study is performed to investigate the effect of tangential velocity on the dynamics of a water droplet impacting on a spinning superhydrophobic surface. It is revealed that an increase in the tangential velocity results in the spreading of a droplet from symmetrical to asymmetrical shape on the superhydrophobic surface. Moreover, depending on the impact and tangential velocities, three behaviors are observed: bouncing, symmetrical splashing, and asymmetrical splashing. In the bouncing regime, it is found that the droplet contact time is independent of impact velocity and decreases as the tangential velocity increases. However, the maximum spreading diameter in this regime is a function of both the impact and the tangential velocities. Furthermore, a splashing threshold defined as WeRe1/21−kRe−1/2V/U2=K is introduced to estimate the transition between the bouncing, symmetrical splashing, and asymmetrical splashing regimes. It is revealed that the value of K in the present work (i.e., superhydrophobic spinning disk) is approximately 60% less than the K value obtained by other researchers for the case of aluminum spinning disk. Moreover, two values are found for k to define the boundaries between these three observed regimes.
Using maize to evaluate the Mohammadi–Khataar (M–K) model as a salinity weighting function (
Authors: Asadi Zahra , Mohammadi Mohammad Hossein , Shorafa Mehdi , Farahbakhsh Mohsen
Published: May 2022

Context Soil water availability, as characterised by the integral water capacity, uses weighting functions based on models not yet evaluated using plants, especially in the context of saline soils. Without plant evaluation such weighting functions remain theoretical at best. Aims We aimed to use maize plants to evaluate Mohammadi and Khataar’s (2018) conceptual model for a salinity weighting function, against those used in Hydrus 1D. Methods We conducted glasshouse experiments with large columns of two sandy loams planted with maize irrigated using different salinities, and repeated without plants. Soil matric suction ranged between saturation and 100 cm, and we measured or predicted plant height, transpiration, evaporation, drainage, storage, and solute concentration over time. The soil water retention curve was measured and the weighted mean hydraulic conductivity was obtained using the van Genuchten model. Key results We found a correlation between our salinity weighting function and the relative transpiration rate of maize (grown in two different soils using irrigation water of three different salinities), particularly in the first few days of growth but not thereafter; errors were related to uncertainties in predicting drainage, salt concentration, and soil water storage in planted columns. Conclusions The deviation of transpiration rate from that predicted by our salinity weighting function at higher salinities may relate to the linear nature of the Maas–Hoffman salinity weighting function plus heterogeneity of soil water and solute distributions. Implications Improving the estimates of drainage and soil water storage in future would make our physical model more useful in larger scale hydrological predictions.
Transsynaptic cerebellin 4–neogenin 1 signaling mediates LTP in the mouse dentate gyrus
Authors: Liakath-Ali Kif , Polepalli Jai S. , Lee Sung-Jin , Cloutier Jean-Francois , Südhof Thomas C.
Published: May 2022

Significance

Synapses are controlled by transsynaptic adhesion complexes that mediate bidirectional signaling between pre- and postsynaptic compartments. Long-term potentiation (LTP) of synaptic transmission is thought to enable synaptic modifications during memory formation, but the signaling mechanisms involved remain poorly understood. We show that binding of cerebellin-4 (Cbln4), a secreted ligand of presynaptic neurexin adhesion molecules, to neogenin-1, a postsynaptic surface protein known as a developmental netrin receptor, is essential for normal LTP at entorhinal cortex→dentate gyrus synapses in mice. Cbln4 and neogenin-1 are dispensable for basal synaptic transmission and not involved in establishing synaptic connections as such. Our data identify a netrin receptor as a postsynaptic organizer of synaptic plasticity that collaborates specifically with the presynaptic neurexin–ligand Cbln4.
The Impact of a Short-Term Mental Health Intervention Delivered in an Australian Prison: A Multi-Cultural Comparison
Authors: Ogloff James R. P. , Rose Arran , Meyer Denny , Benson Sarah , Shepherd Stephane M. , Pfeifer Jeff , Louise Stephanie , Trounson Justin , Skues Jason , Daffern Michael
Published: May 2022

The Australian prison population is increasingly diverse, yet there is limited research assessing the impact of mental health interventions across culturally diverse groups. This study aimed to evaluate the impact of a short-term psycho-educational program on psychological distress, symptoms of mental illness, coping processes, cognitive fusion (i.e., attachment to patterns of thinking or specific thoughts) and somatic issues for 124 people in prison. Cross-cultural comparisons for intervention effects were made for three cultural groups: culturally and linguistically diverse (CALD; N = 45), Indigenous Australian ( N = 24) and English-speaking background (ESB; N = 55). Several differences in intervention outcomes were observed across the cultural groups. Following completion of the program, ESB participants reported significantly reduced levels of depressive symptoms, avoidance coping, cognitive fusion and somatic issues. CALD participants reported significantly reduced somatic issues post-intervention. No significant differences were found in the Indigenous Australian group. These findings indicate that cultural background may influence the effectiveness of mental health interventions delivered within prisons. As such, prisons should aim to offer specialized culturally appropriate mental health services to meet diverse needs.
Lab courses for prospective physics teachers: what could we learn from the first COVID-19 lockdown?
Authors: Jelicic K , Geyer M-A , Ivanjek L , Klein P , Küchemann S , Dahlkemper M N , Susac A
Published: May 2022

At the universities of Dresden, Vienna, and Zagreb, a laboratory course for prospective physics teachers was transferred to an online environment because of the lockdown in March 2020 due to the COVID-19 pandemic. The aim of this paper is to present and compare students’ and instructors’ considerations about the experiences with this laboratory course at these three universities and to formulate guidelines for organizing lab courses for prospective physics teachers. The research was conducted in three steps: first, interviews were conducted with prospective physics teachers (N = 10); second, an online questionnaire was administered to course participants (N = 99); and third, lab course instructors completed an online questionnaire (N = 8). The results show that an increase in creativity and confidence was expressed when conducting home experiments. Students who received support and guidance benefited more from the online lab course, but some students also experienced a greater time commitment. On a positive note, all participants thought outside-the-box during this lab experience and found solutions that led to new ways of conducting labs. Our study suggests that in future online or regular lab courses, students should have the chance to make decisions about experiments and be creative, with an emphasis on peer discussions and support from instructors.
Evaporation of confined droplet between parallel chips with varying gap at room temperature
Authors: Dubey Vikas
Published: May 2022

A theoretical study and experimental validation of the evaporation of a droplet confined between two parallel square chips with a free-standing top chip over a water meniscus is presented in this article. The analytical model describes the surface area of a negatively curved liquid–air interface, and the evaporation model was thus solved for this case. The dynamics of decreasing the gap between the two parallel chips show a linear dependency in time at room temperature. Two main regimes are observed in this case, the constant wetted area regime and the varying wetted area regime. The theoretical study was lastly validated through experiments.
Temperature and pressure effects on microchannels dimensions in hot embossing
Authors: Koochaksaraei Mohammad Mashhadban , Ahmadi Isa , Hajian Ramin , Mohammadi Mohammad Mostafa
Published: May 2022

Hot embossing is a microfabrication technique for making microchannels and microfluidic devices. Temperature and pressure along with the material thermos-mechanical properties are the key parameters in controlling the shape of embossed channels. In this paper, experimental and numerical investigations of pressure and temperature effects on channel dimensions are presented. The material used as workpieces is poly methyl methacrylate (PMMA). The depth, upper width and lower width are the main dimensions of microchannel which are studied in this work. Experiments were performed at temperatures of 140 °C, 150 °C, 160 °C, 170 °C and 180 °C and pressures of 235, 295 and 340 kPa. Numerical and experimental results show a good agreement, i.e. 6.7% difference in dimensional length in the worst case and less than 0.3% in the best case. Based on width and depth values obtained via both experiments and simulations an optimum condition of temperature and pressure is presented in this paper for forming of microchannel on PMMA. Based on performed experiments, 150 °C with 295 kPa is found to be the nearest condition to the optimum point.
Magneto-optical absorption properties of topological insulator thin films
Authors: Hieu Nguyen V , Kubakaddi S S , Hieu Nguyen N , Phuc Huynh V
Published: May 2022

We theoretically study the magneto-optical absorption coefficients (MOACs) and the refractive index changes (RICs) due to both intra- and inter-band transitions in topological insulator (TI) thin films. The interplay between Zeeman energy and hybridization contribution leads to a transition between the normal insulator phase and the TI phase. The difference in the optical response in these two phases as well as at the phase transition point has been analyzed. The influence of the electron density, magnetic field, and temperature on the MOACs and RICs in both intra- and inter-band transitions is investigated. Our results show that the electron density affects directly the threshold energy. At a finite temperature, the thermal excitation causes the triggering of some new transitions which do not appear at T = 0 K. Evidence of the half-peak feature of the first inter-band transition is also found in TI thin films.
A closed local-orbital unified description of DFT and many-body effects
Authors: Flores Fernando , Soler-Polo Diego , Ortega José
Published: May 2022

Density functional theory (DFT) is usually formulated in terms of the electron density as a function of position n(r). Here we discuss an alternative formulation of DFT in terms of the orbital occupation numbers {n

α
} associated with a local-orbital orthonormal basis set {ϕ

α
}. First, we discuss how the building blocks of DFT, namely the Hohenberg–Kohn theorems, the Levy–Lieb approach and the Kohn–Sham method, can be adapted for a description in terms of {n

α
}. In particular, the total energy is now a function of {n

α
}, E[{n

α
}], and a Kohn–Sham-like Hamiltonian is derived introducing the effects of the electron–electron interactions via effective potentials,

{

V

α

eff

=
∂

E

e
e

[

{

n

β

}

]

/
∂

n

α

}

. In a second step we consider the Hartree and exchange energies and discuss how to describe them, in the spirit of a DFT approach, in terms of the orbital occupation numbers. In this contribution special attention is paid to the description of the (intra-atomic) correlation energy and corresponding correlation potentials {V
corr,α
}. For this purpose, a model system is analyzed in detail, whereby an atomic Hamiltonian interacts with the environment via a simplified model; the use of this model allows us to obtain the correlation energy and potentials (in terms of {n

α
}) for different cases corresponding to low, intermediate and high electron correlations.
Electrostatic treatment of charged interfaces in classical atomistic simulations
Authors: Tao Cong , Mutter Daniel , Urban Daniel F , Elsässer Christian
Published: May 2022

Artificial electrostatic potentials can be present in supercells constructed for atomistic simulations of surfaces and interfaces in ionic crystals. Treating the ions as point charges, we systematically derive an electrostatic formalism for model systems of increasing complexity, both neutral and charged, and with either open or periodic boundary conditions. This allows to correctly interpret results of classical atomistic simulations which are directly affected by the appearance of these potentials. We demonstrate our approach at the example of a strontium titanite supercell containing an asymmetric tilt grain boundary. The formation energies of charged oxygen vacancies and the relaxed interface structure are calculated based on an interatomic rigid-ion potential, and the results are analyzed in consideration of the electrostatic effects.
Cloud chamber kit for active learning in a first-year undergraduate nuclear science seminar class
Authors: White A E
Published: May 2022

This paper presents the design and reports on the use of a simple and inexpensive cloud chamber kit that is compatible with active learning, experiential learning, and project-based learning strategies. The kit was developed for use in a first-year undergraduate nuclear science seminar class at a university in the US. Diffusion cloud chambers are commonly used in classroom demonstrations to teach students about cosmic rays and ionizing radiation. A variety of clever and novel cloud chambers found in the literature were built and tested as part of this work and are all suitable for instructor-led classroom demonstrations. However, each has drawbacks that limit its use in hands-on classroom activities as part of active learning, experiential learning, and project-based learning in the classroom. The purpose of this work was to develop a cloud chamber ‘kit’ that can be built in less than 10 min by students during class and guarantees student success in observing background radiation. The cloud chamber kit was found to be highly sensitive to background radiation, and several different types of high-energy particles, including muons or anti-muons, electrons or positrons, photoelectrons, and alpha particles, were detected and identified using the kits at a rate of over 20 tracks per minute measured indoors at sea level at latitude 42.3601° N. The simplicity of the cloud chamber kit presented here makes it compatible with a variety of best practices for active learning in the classroom and requires little preparation time outside of class.
Development of an educational device, based on Arduino, to facilitate the understanding of light diffraction
Authors: Hachmi A , El Hadi M , Essaadaoui R , Mommadi O , Ouariach A , El Moussaouy A
Published: May 2022

The Arduino board and its communication with several sensors are becoming more and more popular in the physical science community. They offer inspiring possibilities for learning different physical concepts. In this article, we focused on creating a very practical educational system for experimenting with diffraction of laser light and graphically visualizing the distribution of light intensity in space, which is impossible to perform it with the devices available in the educational laboratories of physics. The main elements of this configuration are the Arduino UNO microcontroller board, the BH1750 sensor and the NEMA17 motor and its A4990 driver. The results’ graph is displayed in real time on the computer using the Data Streamer add-in. We see that the abbreviated curve corresponds well to the theory. In addition, feedback from the participants in the test activity of the device showed that they were satisfied with its operation and its contribution to the understanding of diffraction. Therefore, we believe that the device presented can play a very important role in the diffraction phenomenon learning because of its high precision and reliability in the measurements.
A mask-compatible, radiolucent, 8-channel head and neck receive array for MRI-guided radiotherapy treatments and pre-treatment simulation
Authors: Zijlema Stefan E , Breimer Wico , Gosselink Mark W J M , Bruijnen Tom , Arteaga de Castro Catalina S , Tijssen Rob H N , Lagendijk Jan J W , Philippens Marielle E P , van den Berg Cornelis A T
Published: May 2022

Immobilization masks are used to prevent patient movement during head and neck (H&N) radiotherapy. Motion restriction is beneficial both during treatment, as well as in the pre-treatment simulation phase, where magnetic resonance imaging (MRI) is often used for target definition. However, the shape and size of the immobilization masks hinder the use of regular, close-fitting MRI receive arrays. In this work, we developed a mask-compatible 8-channel H&N array that consists of a single-channel baseplate, on which the mask can be secured, and a flexible 7-channel anterior element that follows the shape of the mask. The latter uses high impedance coils to achieve its flexibility and radiolucency. A fully-functional prototype was manufactured, its radiolucency was characterized, and the gain in imaging performance with respect to current clinical setups was quantified. Dosimetry measurements showed an overall dose change of −0.3%. Small, local deviations were up to −2.7% but had no clinically significant impact on a full treatment plan, as gamma pass rates (3%/3 mm) only slightly reduced from 97.9% to 97.6% (clinical acceptance criterion: ≥95%). The proposed H&N array improved the imaging performance with respect to three clinical setups. The H&N array more than doubled (+123%) and tripled (+246%) the signal-to-noise ratio with respect to the clinical MRI-simulation and MR-linac setups, respectively. G-factors were also lower with the proposed H&N array. The improved imaging performance resulted in a clearly visible signal-to-noise ratio improvement of clinically used TSE and DWI acquisitions. In conclusion, the 8-channel H&N array improves the imaging performance of MRI-simulation and MR-linac acquisitions, while dosimetry suggests that no clinically significant dose changes are induced.
Developments on auxetic closed cell foam pressure vessel fabrications
Authors: Duncan O , Leslie G , Moyle S , Sawtell D , Allen T
Published: May 2022

Auxetic foam can have higher indentation resistance, better protection under impact and higher vibration damping than conventional foam. Unlike auxetic open cell foam, with established, commercially viable options for manufacturing, methods for making auxetic closed cell foam are not established. We revisited pressure-vessel methods, proposed in 1996, for making auxetic closed cell foam. We processed low-density polyethylene foam for 6 h at 400–700 kPa and 100 °C, causing foams to shrink by a factor of two to five. The volumetric compression kinked cell walls, producing negative Poisson’s ratios as low as −0.2 and Young’s moduli from 0.2 to 1.2 MPa. Trends between applied volumetric compression and Poisson’s ratio agree with those for open cell foam—initially decreasing to negative values as volume reduced by a factor of two after processing, then plateauing or slightly increasing as volume decreased by a factor of two to five. Foams of different sizes and shapes (15–75 mm sides) processed in the same conditions (700 kPa, 6 h, 100 °C) shrank evenly in all three axes and had similar final volume ratios. We noticed a long settling period, of up to three months, where foams slowly shrank. Placing foam in a vacuum after processing reduced the settling period to within 24 h.
Scanning high-sensitive x-ray polarization microscopy
Authors: Marx-Glowna B , Grabiger B , Lötzsch R , Uschmann I , Schmitt A T , Schulze K S , Last A , Roth T , Antipov S , Schlenvoigt H-P , Sergueev I , Leupold O , Röhlsberger R , Paulus G G
Published: May 2022

We report on the realization of an extremely sensitive x-ray polarization microscope, allowing to detect tiniest polarization changes of 1 in 100 billion (10−11) with a μm-size focused beam. The extreme degree of polarization purity places the most stringent requirements on the orientation of the polarizer and analyzer crystals as well as the composition and the form fidelity of the lenses, which must not exhibit any birefringence. The results show that these requirements are currently only met by polymer lenses. Highly sensitive scanning x-ray polarization microscopy thus is established as a new method. It can provide new insights in a wide range of applications ranging from quantum electrodynamics and quantum optics to x-ray spectroscopy, materials research, and laser physics.
A new look at the C
0-formulation of the strong cosmic censorship conjecture
Authors: Iyer Aditya , Yosifov Alexander Y , Vedral Vlatko
Published: May 2022

We examine the C
0-formulation of the strong cosmic censorship conjecture (SCC) from a quantum complexity-theoretic perspective and argue that for generic black hole parameters as initial conditions for the Einstein equations, corresponding to the expected geometry of a hyperbolic black hole, the metric is C
0-extendable to a larger Lorentzian manifold across the Cauchy horizon. To demonstrate the pathologies associated with a hypothetical validity of the C
0 SCC, we prove it violates the ‘complexity = volume’ conjecture for a low-temperature hyperbolic AdS
d+1 black hole dual to a CFT living on a (d − 1)-dimensional hyperboloid H

d−1, where in order to preserve the gauge/gravity duality we impose a lower bound on the interior metric extendability of order the classical recurrence time.
Chaotic shadows of black holes: a short review
Authors: Wang Mingzhi , Chen Songbai , Jing Jiliang
Published: May 2022

We give a brief review on the formation and the calculation of black hole shadows. Firstly, we introduce the concept of a black hole shadow and the current works on a variety of black hole shadows. Secondly, we present the main methods of calculating photon sphere radius and shadow radius, and then explain how the photon sphere affects the boundary of black hole shadows. We review the analytical calculation for black hole shadows which have analytic expressions for shadow boundary due to the integrable photon motion system. And we introduce the fundamental photon orbits which can explain the patterns of black hole shadow shape. Finally, we review the numerical calculation of black hole shadows with the backward ray-tracing method and introduce some chaotic black hole shadows with self-similar fractal structures. Since the gravitational waves from the merger of binary black holes have been detected, we introduce a couple of shadows of binary black holes, which all have eyebrowlike shadows around the main shadows with the fractal structures. We discuss the invariant phase space structures of the photon motion system in black hole space-time, and explain the formation of black hole shadow is dominated by the invariant manifolds of certain Lyapunov orbits near the fixed points.
Self-phase modulation via similariton solutions of the perturbed NLSE Modulation instability and induced self-steepening
Authors: Abdel-Gawad H I
Published: May 2022

The perturbed nonlinear Schrodinger equation (PNLSE) describes the pulse propagation in optical fibers, which results from the interaction of the higher-order dispersion effect, self-steepening (SS) and self-phase modulation (SPM). The challenge between these aforementioned phenomena may lead to a dominant one among them. It is worth noticing that the study of modulation instability (MI) leads to the inspection of dominant phenomena (DPh). Indeed, the MI triggers when the coefficient of DPh exceeds a critical value and it may occur that the interaction leads to wave compression. The PNLSE is currently studied in the literature, mainly on finding traveling wave solutions. Here, we are concerned with analyzing the similarity solutions of the PNLSE. The exact solutions are obtained via introducing similarity transformations and by using the extended unified method. The solutions are evaluated numerically and they are shown graphically. It is observed that the intensity of the pulses exhibits self steepening which progresses to shock soliton in ultra-short time (or near t = 0). Also, it is found that the real part of the solution exhibits self-phase modulation in time. The study of (MI) determines the critical value for the coefficients of SS, SPM, or high dispersivity to occur.
A new concept for a gas proportional scintillation counter: the annular anode
Authors: Silva P.A.O.C. , Azevedo C.D.R. , Fernandes L.M.P. , dos Santos J.M.F. , Monteiro C.M.B.
Published: May 2022

A new design of a Gas Proportional Scintillation Counter (GPSC) for X-ray spectrometry is presented and a proof of concept is demonstrated. The proposed design is much simpler, having only one electrode, the anode. In addition, this electrode has an annular shape with its axis aligned with the photosensor axis. Since the scintillation region is limited to a small region near the anode, the solid angle subtended by the photocathode is similar relative to any position in the scintillation region and the amount of scintillation reaching the photosensor is independent from the position where the radiation interaction occurs. Standard GPSCs with uniform electric field design have the scintillation region parallel to the photosensor active area resulting in a dependence of the amount of light collected by the photosensor on the axial distance of the radiation interaction due to solid angle effects. These effects impose limitations on the size of the detector radiation window relative to the photosensor active area. Therefore, the annular anode allows to obtain a GPSC design with a larger radiation window relative to the photosensor area. A first GPSC prototype with a 10-cm diameter annular anode placed at a distance of 4.4 cm from the photosensor has an energy resolution of 14% for anode voltages of 8 kV and, according to simulations, it can reach 11% for anode voltages of 12 kV. This is worse than the values of 8–9% obtained with a standard GPSC which, on the other hand, have a window-to-photosensor diameter ratio lower than 0.8. Simulations have shown that the main factor degrading the energy resolution in this new design is the low number of photons impinging the photosensor due to the low solid angle subtended by the photosensor relative to the electroluminescence region of the detector. A compromise has to be made between the anode-to-photosensor diameter ratio as well as between the anode-to-photosensor distance and the energy resolution that can be achieved with the annular anode design.
Ultra-low jitter clock distribution for the trigger electronics of the New Small Wheel for the ATLAS experiment
Authors: Alexopoulos T. , Geralis T. , Gkountoumis P. , Levinson L. , Mesolongitis I. , Zormpa O.
Published: May 2022

The Large Hadron Collider (LHC) at CERN plans to have a series of upgrades to increase its instantaneous luminosity to 7.5 × 1034 cm−2 s−1. The increased luminosity drastically impacts the ATLAS trigger and readout data rates. The inner-most station of the ATLAS muon spectrometer, the so-called Small Wheels is being replaced with a New Small Wheel (NSW) system, consisting of Micromegas and small-strip Thin Gap Chambers (sTGC) detectors. The on-detector radiation levels required radiation tolerant electronics. The lower radiation levels on the rim of the NSW allowed utilizing commercial electronic chips, such as Field Programmable Gate Arrays (FPGAs), in the trigger chain of the sTGC detectors. Those FPGAs require an ultra-low jitter clock for the proper operation of their Gigabit transceivers (4.8 Gb/s serial links). The initial design was based on a clock provided by a radiation tolerant ASIC designed at CERN, but due to its intrinsic jitter and consequent marginal error rate on the transmission lines, a different approach had to be chosen. An additional clock source based on commercial jitter cleaners, fanout chips and optical transmitters driving dedicated fibers was built. The new scheme provides 64 low-jitter clocks (32 main and 32 redundant) from the radiation-protected area (USA15) to the trigger electronics over 60 m of OM3 fiber.
Environmentally friendly fabrication of electrospun nanofibers made of polycaprolactone, chitosan and κ-carrageenan (PCL/CS/κ-C)
Authors: Vargas-Osorio Zulema , Ruther Florian , Chen Si , Sengupta Susanta , Liverani Liliana , Michálek Martin , Galusek Dušan , Boccaccini Aldo R
Published: May 2022

Electrospun fibers based on biodegradable polyanionic or polycationic biopolymers are highly beneficial for biomedical applications. In this work, electrospun nanofibers made from poly(epsilon caprolactone) (PCL), chitosan (CS) and κ-carrageenan (κ-C) were successfully fabricated using several mixtures of benign solvents containing formic acid and acetic acid. The addition of κ-C improved the preparation procedure for the production of PCL/CS fibers by electrospinning. Moreover, a polymer mixture was selected to be stored at −20 °C for one month with the purpose to study the properties of the resulting fiber mat. The results indicated that fiber characteristics were not seriously compromised compared to the ones of those fabricated with the original solution, which represents an important reduction in produced waste. Thus, the interactions that occur between positively and negatively charged hydrophilic polysaccharides might induce higher stability to the linear aliphatic polyester in the polymer mixture. All fiber mats were morphologically, physico-chemically and mechanically characterized, showing average fiber diameters in the nano scale. A direct cell viability assay using ST-2 cells demonstrated cell proliferation after seven days of incubation for all prepared fiber mats, confirming their suitability as potential candidates for bone tissue engineering and wound healing applications.
Carbon footprint of American lifestyles: a geodemographic segmentation approach
Authors: Baiocchi Giovanni , Feng Kuishuang , Hubacek Klaus , Walters Cole
Published: May 2022

In order to deliver substantial reductions of U.S. residential emissions, cost-effective responses to climate change will need to recognize changes in consumer behavior and lifestyles as important mechanisms to mitigate carbon dioxide emissions. Marketing experts have long recognized the usefulness of developing composite variables to target specific consumer lifestyles and have subsequently developed market segmentation approaches to express relationships between geodemographics and consumer behavior. This paper represents the first use of detailed segmentation data to look at US footprint at high spatial resolution. We employ market segmentation data to delineate lifestyles for approximately 70 000 census tracts in the US and develop a spatial framework to better conceptualize lifestyles as location specific typologies of emission drivers. We find that lifestyles are not only very useful in explaining variations in emissions but in fact are as important as income, typically recognized as the major determinant of consumption emissions. Results from our analysis link the differences between suburban and urban footprints directly to lifestyle patterns and illustrate the geographic distribution of emissions resulting from households’ consumption. We find that statistical clustering and consumer classification methods provide a unique perspective for understanding how various CO2 drivers interact and impact household emissions. Our proposed framework suggests that carbon mitigation strategies should move beyond a ‘one-size-fits-all’ approach centered on income and account for community specific lifestyle impacts related to consumer preferences and demographic characteristics at fine spatial scale.
Phytochemical screening of Malaysian Dipterocarpaceae species from Kuala Keniam, Taman Negara Pahang
Authors: Kamarozaman A S , Adnan N , Saidon N A , Rahman N F A , Johari M S M , Ahmat N
Published: May 2022

The diverse family of Dipterocarpaceae is well-known for its timber as well as the phytochemical constituents which possess medicinal properties. In this preliminary study, 10 Dipterocarpaceae species namely Anisoptera laevis, Dipterocarpus crinitus, Dipterocarpus gracilis, Hopea nervosa, Hopea pubescens, Shorea hopeifolia, Shorea ovalis, Shorea parviflora, Vatica bella and Vatica maingayi were collected from Kuala Keniam, Taman Negara Pahang, Malaysia. The selected parts of the species were macerated in methanol and phytochemically screened to determine the presence of alkaloids, flavonoids, glycosides, saponins, tannins and terpenoids. The results revealed that all crude methanolic extracts were found to contain tannins and terpenoids. Additionally, the crude extracts from the stem bark of D. gracilis and the leaves of H. pubescens were observed to contain alkaloids, flavonoids, reducing sugar, saponins, tannins as well as terpenoids. Further studies on all species are recommended in search for the bioactive chemical constituents that might be beneficial in the development of drug discovery.
Perceptions on The Therapeutic Effects of Stingless Bee Honey and its Potential Value in Generating Economy among B40 Community of Kampung Bukit Kuin, Kuantan
Authors: Jalil Mohd Azri Abd , Damit Aifa Syazwani Ag , Zakaria Farahiya Zalikha , Hasan Muhammad Kamil Che , Isa Muhammad Lokman Md , Ahmad Azmir
Published: May 2022

Meliponiculture or keeping stingless bee in Malaysia is expanding and has the potential to generate money for the the bottom 40% of income earners (B40). The increased production of stingless bee honey as a complementary medicine as a therapeutic medium for health for a variety of reasons. Thus, this study aimed to explore the experiences and perceptions on the therapeutic effects of stingless bee honey and its potential value in generating economy among the B40 community. Semi-structured interviews were carried out among the B40 community who participated in the Desa Kelulut project of Kampung Bukit Kuin, Kuantan. The data were analysed using thematic analysis. A total of six respondents interviewed in the study out of 20 participants. Four themes emerged, namely, benefit of stingless bee honey; market supply and economy; sustaining the farm; and facilitate income. The participants valued the beneficial properties of the honey toward health and acknowledged the potential of the stingless bee honey to be marketed in Malaysia as well as generating income for the B40 community of Kampung Bukit Kuin, Kuantan.
Floor plants’ leaf shape and Phyllagathis rotundifolia’s soil organic matter in Kuala Keniam Trail, Pahang National Park
Authors: Mokhtar M , Abd Rahman N H , Abd Razak N A , Omar M , Abdul Rahman M S , Wan Kamaruddin W Z
Published: May 2022

Kuala Keniam forest in the Pahang National Park is a part of the oldest and most complex ecosystem in the world with multispecies of plants and structures. Unfortunately, near to none information was documented on the geometrical aspects of leaves. Thus, this study aims to pre-document on the variety of shapes of leaves along the trail and classify them. Photographs of the plants and all site activities were taken and documented by using the digital single-lens reflex (DSLR) and smartphone-digital cameras. Secondly, this study also aims at understanding this one particular herbaceous plant, known as Phyllagathis rotundifolia (tapak sulaiman) which is commonly found along the trail, and traditionally used to relieve gastrointestinal problems and fever. The composition of the soil organic matter of the plant were collected for better understanding of the type of soil needed for mass-cultivation and medical purposes. The Walkley-Black (WB) titration method was used to analyse the soil, where the oxidation of organic matter by potassium dichromate (K2Cr2O7)-sulfuric acid mixture followed by back titration of the excessive dichromate by ferrous ammonium sulphate (Fe (NH4)2(SO4)2.6H2O) were monitored. Findings from the Kuala Keniam trails were documented and analysed. Thirty distinct-leaves have been identified and classified into 10-distinct leaf shape categories. Rich soil contents such as iron, carbon and phosphorous were also detected, thus creating Kuala Keniam as an excellent environment for the growth of beneficial shrubs and herbs