bluuebunny/crossref_metadata_2025 huggingface dataset:
Case Series of Skull Base Meningioma Resection in the Octogenarian Population
Authors: Kusyk Dorian M. , Mao Gordon , Dabecco Rocco , Yu Alexander K.
Published: February 2021

Introduction The geriatric population is the fastest growing segment of the American population, and octogenarians are increasingly seen by neurosurgeons for relatively common lesions such as meningiomas. Unfortunately, providers do not have clear data to guide decision-making regarding these lesions, particularly if they involve the skull base. Current research in outcomes among the elderly looks at a wide range of ages, often anyone older than 65. Previous studies in octogenarians report a wide-range of mortality rates and do not focus on skull base lesions. This paper strives to clarify the experiences and outcomes of octogenarians.

Patients and Methods This retrospective series reviews skull base tumor surgeries performed at a single academic institution over the past 15 years in octogenarian patients. Primary endpoint was 30-day mortality; however, potential risk factors, perioperative morbidity, postdischarge disposition, and longer term follow-up were also captured. Multivariate logistic regression was performed to identify relevant perioperative and medical characteristics that increases the risk of adverse events.

Results Fourteen patients underwent craniotomies for skull base procedures with an average age of 84.5, with a 14% 30-day mortality rate. One patient required a tracheostomy on discharge and approximately half were able to either go home or rehabilitation after their procedure. On statistical analysis, there were no noted characteristics that predisposed any of the patients to a poorer outcome.

Conclusion Octogenarian patients were able to tolerate surgery for skull base meningiomas resection. This outcome data may be used to inform surgical decision and guide conversation with patients and their families.
Morphological Measurement and Anatomical Variations of the Clivus Using Computed Tomography
Authors: Serindere Gozde , Gunduz Kaan , Avsever Hakan
Published: February 2021

Objectives The aim of this study was to evaluate the clivus morphology, including fossa navicularis magna (FNM), canalis basilaris medianus (CBM), and craniopharyngeal canal (CC), on computed tomography (CT) images.

Design This is a retrospective study.

Setting Faculty of Dentistry, Department of Dentomaxillofacial Radiology.

Participants The CT images of 500 patients (253 males; 247 females) were evaluated.

Main Outcome Measures The prevalence of FNM, CBM, and CPC; the length, width, and depth of FNM; and CBM types were recorded. Also, a morphological analysis of the clivus (length of the clivus, angle between the clivus and the posterior margin of the foramen magnum, angle between the clivus and the dens axis, and anteroposterior diameter of the foramen magnum) was performed.

Results FNM was identified in 5.4%, CBM in 4%, and CC in 0.8% of the study group. Type 5 CBM was not found. Type 6 was the most common CBM type. There was no significant correlation between the age and gender of patients with FNM. There were significant differences between the clivus length, the angle between the clivus and the dens axis, the anteroposterior diameter of the foramen magnum, and gender. Also, there was a significant difference between the angle between the clivus and the foramen magnum and age.

Conclusions The anatomical variations of the clivus are rare and important for the oral and maxillofacial radiologist to make the differential diagnosis. These anatomical variations should not be confused with pathologic formations. The morphological measurements and anatomical variations of the clivus can be evaluated in detail on CT images.
Skull Base Aerosol Generating Cases Amidst the COVID-19 Pandemic: An Experience from the Epicenter
Authors: Dastagirzada Yosef , Klauberg Olga , Sheerin Kathleen , Lieberman Seth , Lebowitz Richard , McMenomey Sean , Sen Chandranath , Roland J Thomas , Golfinos John G. , Pacione Donato
Published: February 2021

Soon after the World Health Organization declared the severe acute respiratory syndrome coronavirus 2 a global health emergency on January 30, 2020, New York City was plagued by the virus and its health system and economy pushed to their limits. The majority of the limited neurosurgical data in relation to COVID-19 is anecdotal and the higher theoretical risk of transmission of the virus among skull base aerosol generating (SBAG) cases has not been investigated or discussed in a neurosurgical population. We discuss a series of 13 patients who underwent 15 SBAG surgical procedures during the peak of COVID-19 in our hospital system and the protocols use perioperatively for their procedures. Our data support that with proper preoperative testing, a well-delineated surgical algorithm, and appropriate personal protective equipment, emergent/urgent cases can be done safely in hospitals that are currently experiencing high volumes of COVID-19 cases as we did in March to May of 2020.
Primary and Secondary Optic Nerve Sheath Meningioma
Authors: Solli Elena , Turbin Roger E.
Published: February 2021

Objective This study was aimed to review issues relating to the recognition, radiographic diagnosis, monitoring, and management of primary and secondary optic nerve sheath meningioma (ONSM).

Design This study is a review of peer-reviewed literature combined with illustrative case studies.

Participants and Methods A literature search was conducted via the PubMed database using pertinent search terms. Selected articles were limited to those written or translated into English. Additional works cited within articles were also included. Individual cases were drawn from the experience of a tertiary academic neuroophthalmic and orbital practice. Tables summarize radiotherapeutic and surgical studies, excluding single case reports and studies focusing on meningioma of intracranial origin.

Main Outcome Measurements Review of reported surgical and radiotherapeutic series is the primary measurement.

Results The natural history of optic nerve sheath meningiomas is primarily characterized by progressive ipsilateral vision loss. Diagnosis is typically based on radiographic imaging findings, with biopsy remaining indicated in some patients. Management strategies may include observation, radiation, and/or surgical intervention, or a combination of these approaches. The role of surgery, especially with respect to primary ONSM (pONSM), remains controversial. Advancement of radiotherapy techniques has shifted modern treatment paradigms in pONSM toward radiation as primary treatment, as surgical outcomes are inferior in major studies. Although radiation remains the treatment of choice in many cases, selected patients may benefit from surgery, especially in the setting of secondary ONSM (sONSM).

Conclusion A wide variety of radiotherapeutic and surgical treatment modalities for ONSM exist. The specific indications for each management strategy continue to be redefined.
Direct Oral Anticoagulants in the Treatment of Venous Thromboembolism: Use in Patients with Advanced Renal Impairment, Obesity, or Other Weight-Related Special Populations
Authors: Dobesh Paul P. , Kernan Molly M. , Lueshen Jenni J.
Published: February 2021

There are currently more than 7 million patients taking a direct oral anticoagulant (DOAC), with more new prescriptions per year than warfarin. Despite impressive efficacy and safety data for the treatment of venous thromboembolism, patients with obesity or advanced renal impairment represented a small portion of the patients enrolled in the phase 3 clinical trials. Therefore, to evaluate the potential use of DOACs in these special populations, clinicians need to have an understanding of the pharmacokinetics and pharmacodynamics of these agents in these settings. Since data from randomized controlled trials are limited, data from observational trials are helpful in gaining comfort with the use of DOACs in these special populations. Selecting the appropriate dose for each agent is imperative in achieving optimal patient outcomes. We provide an extensive review of the pharmacokinetics, pharmacodynamics, phase 3 clinical trials, and observational studies on the use of DOACs in patients with advanced renal impairment, obesity, or other weight-related special populations to provide clinicians with a comprehensive understanding of the data for optimal drug and dose selection.
ECLS for Life-Threatening Complications in Mesothelioma Surgery: Is It Worthwhile?
Authors: Bellini Alice , Dell'Amore Andrea , Ferrigno Pia , Sella Nicolo' , Navalesi Paolo , Rea Federico
Published: February 2021

Extracorporeal life support (ECLS) is an effective method for bridging patients to recovery in cases of respiratory and/or cardiac failure that are potentially reversible and unresponsive to conventional management. Nevertheless, there have been only few reports about the use of ECLS in oncological patients with complications due to their neoplasm or its treatment. We report the use of veno-arterial extracorporeal membrane oxygenation in three cases of severe perioperative complications following surgery for mesothelioma after induction chemotherapy at our Institution.
Harmonic detection method based on permutation entropy and variational modal decomposition optimized by genetic algorithm
Authors: Zhang ShuQing , Zhang Yun
Published: February 2021

In order to accurately extract harmonic components in power signals, a harmonic detection method based on variational mode decomposition (VMD) optimized by the genetic algorithm and permutation entropy is proposed. The genetic algorithm optimizes VMD, which can improve the difficulty of parameter selection of VMD. The combination of optimized VMD and permutation entropy can simultaneously utilize the complete decomposition of VMD and the sensitivity to the time of permutation entropy and quickly and effectively filter out various interference signals of power systems. The simulation experiment and engineering application prove that compared with empirical mode decomposition and ensemble empirical mode decomposition harmonic detection methods, this method can effectively filter out noise under a low signal-to-noise ratio and achieve a higher harmonic detection accuracy.
Nonlinear excitations of magnetosonic solitary waves and their chaotic behavior in spin-polarized degenerate quantum magnetoplasma
Authors: Rahim Zakia , Adnan Muhammad , Qamar Anisa
Published: February 2021

The quantum hydrodynamic model is used to study the nonlinear propagation of small amplitude magnetosonic solitons and their chaotic motions in quantum plasma with degenerate inertialess spin-up electrons, spin-down electrons, and classical inertial ions. Spin effects are considered via spin pressure and macroscopic spin magnetization current, whereas the exchange effects are considered via adiabatic local density approximation. By applying the reductive perturbation method, the Korteweg–de Vries type equation is derived for small amplitude magnetosonic solitary waves. We present the numerical predictions about the conservative system’s total energy in spin-polarized and usual electron–ion plasma and observed low energy in spin-polarized plasma. We also observe numerically that the soliton characteristics are significantly affected by different plasma parameters such as soliton phase velocity increases by increasing quantum statistics, magnetization energy, exchange effects, and spin polarization density ratio. Moreover, it is independent of the quantum diffraction effects. We have analyzed the dynamic system numerically and found that the magnetosonic solitary wave amplitude and width are getting larger as the quantum statistics and spin magnetization energy increase, whereas their amplitude and width decrease with increasing spin concentration. The wave width increases for high values of quantum statistic and exchange effects, while their amplitude remains constant. Most importantly, in the presence of external periodic perturbations, the periodic solitonic behavior is transformed to quasiperiodic and chaotic oscillations. It is found that a weakly chaotic system is transformed to heavy chaos by a small variation in plasma parameters of the perturbed spin magnetosonic solitary waves. The work presented is related to studying collective phenomena related to magnetosonic solitary waves, vital in dense astrophysical environments such as pulsar magnetosphere and neutron stars.
Resonances as viscosity limits for exponentially decaying potentials
Authors: Xiong Haoren
Published: February 2021

We show that the complex absorbing potential method for computing scattering resonances applies to the case of exponentially decaying potentials. This means that the eigenvalues of −Δ + V − iɛx2 and |V(x)| ≤ Ce−2γ|x| converge, as ɛ → 0+, to the poles of the meromorphic continuation of (−Δ+V−λ2)−1 uniformly on compact subsets of Re λ > 0, Im λ > − γ, and arg λ > −π/8.
Denoising electron holograms using the wavelet hidden Markov model for phase retrieval—Applications to the phase-shifting method
Authors: Tamaoka Takehiro , Midoh Yoshihiro , Yamamoto Kazuo , Aritomi Shodai , Tanigaki Toshiaki , Nakamura Masao , Nakamae Koji , Kawasaki Masashi , Murakami Yasukazu
Published: February 2021

Noise reduction using the wavelet hidden Markov model (WHMM) was applied to electron holograms of a LaFeO3/SrTiO3 specimen, which was subjected to phase retrieval by the phase-shifting method. A systematic study revealed the optimal conditions regarding the electron dose and number of holograms used for phase retrieval, for which the effect of denoising was most pronounced. The denoised holograms revealed the magnitude of the phase shift at the LaFeO3/SrTiO3 interface, while the original, noisy holograms did not allow for accurate measurements. The observations demonstrate the usefulness of denoising using the WHMM.
Plasma-wall transition in two ion species plasma with bi-Maxwellian electrons
Authors: Basnet Suresh , Khanal Raju
Published: February 2021

Presheath and sheath structures of collisional two ion species (helium and argon) plasma in the presence of bi-Maxwellian electrons have been investigated by using a fluid model. As the thermal energy of hot electrons is higher than cold electrons, the electron impact ionization process is governed by the concentration of hot electrons. The velocity of positive ions at the sheath boundary, i.e., the Bohm criterion, gets modified in the presence of ion–neutral drag force, source term, and bi-Maxwellian electrons. It is found that the ion–neutral drag force, ionization rates, and volumetric composition of electrons affect the characteristics of the presheath and sheath. The scale length of the sheath region widens from about 1.09 mm to 5.80 mm with the increase in the concentration of hot electrons. The acoustic speed of helium ions at the sheath boundary is higher than its common speed, whereas the acoustic speed of argon ions is lower than its common speed. The common speed of positive ions at the sheath boundary is slower by 13% in magnitude than in the collisionless case. Furthermore, the effect of ion–neutral drag force on streaming instability for two ion species plasma has been systematically presented.
Brilliant attosecond γ-ray emission and high-yield positron production from intense laser-irradiated nano-micro array
Authors: Zhang Liang-qi , Wu Shao-dong , Huang Hai-rong , Lan Hao-yang , Liu Wei-yuan , Wu Yu-chi , Yang Yue , Zhao Zong-qing , Zhu Zhi-chao , Luo Wen
Published: February 2021

We investigate a novel scheme for brilliant attosecond γ-ray emission and high-yield positron production, which is accomplished with an ultra-intense laser pulse incident upon a Nano-Micro-array (NMA) with a substrate incorporated. This scheme is able to realize effectively electron acceleration and colliding geometry. Both the γ-ray flash and positron bunch are, then, generated with high conversion efficiency. At a laser intensity of 8 × 1023 W/cm2, ∼27% of the laser energy is transferred successfully into γ-rays and ∼0.7% of the laser energy into the positrons. As a consequence, ultra-short (∼440 as) and ultra-brilliant (∼1024 photons s−1 mm−2 mrad−2 per 0.1%BW at 15 MeV) γ-ray burst and high-yield (1.48 × 1011) and overdense (∼1022 cm−3) positron bunches are generated. We found a sub-linear scaling of laser-to-photon conversion efficiency (∝I00.75) and a superlinear scaling of laser-to-positron conversion efficiency (∝I02.5) with the laser intensity. Multi-dimensional particle-in-cell simulations show that particle (γ photon and positron) generation can be manipulated by the laser-focusing position and NMA's length and spacing. Optimal conditions for particle generation in NMAs are obtained, indicating that microwire arrays have the advantage over nanowire arrays in particle generation in the extreme laser fields. Furthermore, positron annihilation effects in the high-energy-density (HED) environment are discussed. The scheme using NMAs would provide effective avenues toward investigating attosecond nuclear science and HED physics with the coming 10 PW laser facilities.
Falling off a limit cycle using phase-agnostic stimuli: Applications to clinical oscillopathies
Authors: Chang Joshua , Paydarfar David
Published: February 2021

For over a century, physiological studies have shown that precisely timed pulses can switch off a biological oscillator. This empiric finding has shaped our mechanistic understanding of how perturbations start, stop, and reset biological oscillators and has led to treatments that suppress pathological oscillations using electrical pulses given within specified therapeutic phase windows. Here, we present evidence, using numerical simulations of models of epileptic seizures and reentrant tachycardia, that the phase window can be opened to the entire cycle using novel complex stimulus waveforms. Our results reveal that the trajectories are displaced by such phase-agnostic stimuli off the oscillator's limit cycle and corralled into a region where oscillation is suppressed, irrespective of the phase at which the stimulus was applied. Our findings suggest the need for broadening theoretical understanding of how complex perturbing waveforms interact with biological oscillators to access their arrhythmic states. In clinical practice, oscillopathies may be treated more effectively with non-traditional stimulus waveforms that obviate the need for phase specificity.
Quantitative digital microscopy with deep learning
Authors: Midtvedt Benjamin , Helgadottir Saga , Argun Aykut , Pineda Jesús , Midtvedt Daniel , Volpe Giovanni
Published: February 2021

Video microscopy has a long history of providing insight and breakthroughs for a broad range of disciplines, from physics to biology. Image analysis to extract quantitative information from video microscopy data has traditionally relied on algorithmic approaches, which are often difficult to implement, time-consuming, and computationally expensive. Recently, alternative data-driven approaches using deep learning have greatly improved quantitative digital microscopy, potentially offering automatized, accurate, and fast image analysis. However, the combination of deep learning and video microscopy remains underutilized primarily due to the steep learning curve involved in developing custom deep-learning solutions. To overcome this issue, we introduce software, DeepTrack 2.0, to design, train, and validate deep-learning solutions for digital microscopy. We use this software to exemplify how deep learning can be employed for a broad range of applications, from particle localization, tracking, and characterization, to cell counting and classification. Thanks to its user-friendly graphical interface, DeepTrack 2.0 can be easily customized for user-specific applications, and thanks to its open-source, object-oriented programing, it can be easily expanded to add features and functionalities, potentially introducing deep-learning-enhanced video microscopy to a far wider audience.
Characteristics of secondary electron emission and multipactor from a nested microtrap structure surface
Authors: Liu Lu , Feng Guobao , Chen Bangdao , Wang Ning , Cui Wanzhao
Published: February 2021

It is known that an appropriate surface structure can suppress the secondary electron emission as a result of the receded multipactor in a spacecraft microwave component. On the other hand, the multiplier effect caused by electron re-entrance in ordinary surface structures can degrade the suppression of secondary electron emission. The present paper concerns our proposition of a new type of two-level nested microtrap structure surface able to effectively inhibit the generation of the secondary electrons inside the trap structure to achieve better suppression of the total secondary electron emission on the surface. The surface of a two-level nested microtrap array structure was obtained by lithography, stripping, dry etching, and Ag sputtering. Experimental tests were conducted on the two proposed nested structures with different sizes. The test results show that inhibition effects of the two structures have been improved by 100% and 144% compared with those of the traditional single-hole trap structure. The secondary electron yield on the bottom surface of the rough nested trap due to Ag sputtering is higher than that of the ideal regular structure simulated by Monte Carlo. In addition, the larger depth-to-width ratio of the nested trap can inhibit the multi-generation multiplication of electrons in the trap more effectively and further improve the inhibition effect on secondary electrons. For an impedance transformer, the proposed two size nested structure surface can increase the multipactor power threshold by about 346% and 386%. This method plus the nested microtrap structure can achieve a better secondary electron emission suppression effect and further improve the multipactor threshold of space microwave components.
A unique multianvil 6–6 assembly for a cubic-type multianvil apparatus
Authors: Fuchizaki Kazuhiro , Wada Tomoyuki , Naruta Hiroki , Suzuki Akio , Irino Kazuo
Published: February 2021

A unique way to assemble a set of second-stage anvils for a cubic multianvil apparatus when used in a 6–6 mode is proposed. A plastic frame supporting the second-stage anvils along with a newly designed tool allows us to assemble the second-stage anvils within a few minutes. The precision of anvil alignment is even better than the one attained by the ordinary method, which assembles the anvils within a metal frame in a quite time-consuming way. In situ experiments utilizing a synchrotron x-ray source proved a stable operation under 1500 K and about 10 GPa. The quick and accurate assembling feature of our device may ensure a minimum loss of beam time given in such a facility.
Prospects for hole doping in dilute-anion III-nitrides
Authors: Goodrich Justin C. , Tan Chee-Keong , Borovac Damir , Tansu Nelson
Published: February 2021

Efficient p-type doping of III-nitride materials is notoriously difficult due to their large bandgaps, intrinsic n-type doping, and the large ionization energy of acceptors. Specifically, aluminum-containing nitrides such as AlN and AlGaN have demonstrated low p-type conductivity, which increases device resistances and reduces carrier injection in optoelectronic applications. Dilute-anion III-nitride materials are a promising solution for addressing this issue and increasing the activation efficiency of p-type dopants. The upward movement of the valence bands in these materials reduces the ionization energy of the dopants, allowing for enhanced p-type conductivity in comparison to the conventional nitrides. Incorporation of a dilute-arsenic impurity into AlN is hypothesized to significantly reduce the ionization energy of Mg-acceptors from 500 meV to 286 meV, allowing for a two-order magnitude increase in activation efficiency in 6.25%-As AlNAs over that of AlN.
Postnatal cadmium administration affects the presence and distribution of carbohydrates in the sperm membrane during maturation in the epididymis in adult Wistar rats
Authors: Hernández-Rodríguez Joel , Arenas-Ríos Edith , Jiménez-Morales Irma , Cortés-Barberena Edith , Montes Sergio , Vigueras-Villaseñor Rosa María , Arteaga-Silva Marcela
Published: February 2021

Cadmium (Cd) is a heavy metal related to a decrease in sperm parameters. The transit of spermatozoa through the epididymis is necessary to generate changes in the sperm membrane, such as the assembly of various carbohydrates that are added to the spermatazoan’s surface to prepare it for successful fertilisation of the oocyte. No studies have yet analysed whether Cd alters the presence and distribution of these carbohydrates. We aimed to evaluate the changes induced by Cd in the distribution pattern of N-acetylglucosamine, sialic acid, mannose and fucose on the sperm membrane in the epididymis (e.g. caput, corpus, cauda) and if it alters the epididymal epithelium. Male Wistar pups were treated with Cd doses (0.125, 0.25 and 0.5mg/kg) on postnatal days 1–49. At postnatal day 90, they were humanely killed, sperm samples were obtained from the epididymis and tissue samples were taken for histological analysis. Cd concentrations in the blood and epididymis increased in proportion to the dose administered and decreased the serum testosterone levels and sperm quality. Histological analysis revealed alterations in the epithelium in all Cd-treated groups. Cd altered the distribution patterns of carbohydrates and fluorescence indices. All these alterations affected the structure and functioning of sperm.
The inflated significance of neutral genetic diversity in conservation genetics
Authors: Teixeira João C. , Huber Christian D.
Published: February 2021

The current rate of species extinction is rapidly approaching unprecedented highs, and life on Earth presently faces a sixth mass extinction event driven by anthropogenic activity, climate change, and ecological collapse. The field of conservation genetics aims at preserving species by using their levels of genetic diversity, usually measured as neutral genome-wide diversity, as a barometer for evaluating population health and extinction risk. A fundamental assumption is that higher levels of genetic diversity lead to an increase in fitness and long-term survival of a species. Here, we argue against the perceived importance of neutral genetic diversity for the conservation of wild populations and species. We demonstrate that no simple general relationship exists between neutral genetic diversity and the risk of species extinction. Instead, a better understanding of the properties of functional genetic diversity, demographic history, and ecological relationships is necessary for developing and implementing effective conservation genetic strategies.
Precise initial abundance of Niobium-92 in the Solar System and implications for
p
-process nucleosynthesis
Authors: Haba Makiko K. , Lai Yi-Jen , Wotzlaw Jörn-Frederik , Yamaguchi Akira , Lugaro Maria , Schönbächler Maria
Published: February 2021

Significance

Niobium-92 is a short-lived
p
-process isotope that decays to
92
Zr with a half-life of 37 Ma. The initial
92
Nb/
93
Nb ratio of the Solar System is crucial for utilizing the
92
Nb–
92
Zr chronometer, as it has the potential to provide information on early Solar System evolution and insights into the debated
p
-process nucleosynthesis. Herein, we precisely determine the initial
92
Nb/
93
Nb ratio of the Solar System using rare minerals in meteorites. This significantly improved precision makes the
92
Nb–
92
Zr chronometer a powerful tool for providing precise ages of accretion, differentiation, and collision for asteroids and planets. Additionally, the initial ratio reveals that both type Ia supernovae and core-collapse supernovae contributed to the nucleosynthesis of the
p
-process isotope
92
Nb in our Solar System.
Kinetic description of site ensembles on catalytic surfaces
Authors: Razdan Neil K. , Bhan Aditya
Published: February 2021

Significance

The kinetic assessment of catalytic reactions is essential to the design and application of thermochemical processes useful in petrochemical synthesis, energy conversion, and environmental remediation. We demonstrate that the ubiquitously used Langmuir–Hinshelwood formalism is incomplete and fails to correctly describe even simple catalytic reactions (e.g., A + A → A2). An accurate kinetic description requires explicit rate equations for multisite configurations (e.g., A*–A* pairs) to account for the nonrandom clustering/isolation of surface species. We rigorously describe clustering/isolation phenomena by derivation of coverage-dependent stoichiometric coefficients, which capture the distinct influence each elementary step exerts on each catalytic site ensemble—thereby overcoming limitations of the mean-field (i.e., Hinshelwood) assumption in describing reactions of mobile Langmuirian adsorbates on catalytic surfaces.
Transcriptional control of local auxin distribution by the CsDFB1-CsPHB module regulates floral organogenesis in cucumber
Authors: Nie Jing , Shan Nan , Liu Huan , Yao Xuehui , Wang Ziwei , Bai Ruoxue , Guo Yicong , Duan Ying , Wang Changlin , Sui Xiaolei
Published: February 2021

Significance

Auxin is a key phytohormone influencing multiple aspects of plant development, including meristem maintenance, primordia initiation, floral organogenesis, and vascular differentiation. Local auxin biosynthesis and polar auxin transport are essential to establish and maintain auxin gradients that ensure proper plant development. Here, we demonstrate that CsDFB1, a member of the plant cystatin superfamily, which was previously implicated in defense responses, plays a critical role in regulating local auxin distribution and thus influences floral organogenesis in cucumber. Genetic and biochemical assays suggest that CsDFB1 affects local auxin distribution by acting as an attenuator that interacts with CsPHB and modulates CsPHB-mediated transcriptional control of
CsYUC2
and
CsPIN1
. Our results shed light on the fine tuning of local auxin distribution in plants.
A letter from Zellig Harris to André Lentin
Authors: Nevin Bruce
Published: February 2021

Toward the end of his life, Zellig Harris (1909–1992) wrote a brief account of the origins and development of his work to establish the foundations of a science of language on mathematical principles. A French translation was published in 1990, and in the same publication appeared a parallel appraisal from a mathematical point of view by André Lentin (1913–2015). Early the following year, having reread Lentin’s essay several times, Harris wrote him the letter which is presented here. More than a gesture of thanks and appreciation, this letter further illuminates the comprehensive overview afforded by the two essays, both of which appeared in English in 2002.
#StayHome – A pragmatic analysis of COVID-19 health advice in Saudi and Australian tweets
Authors: El-Dakhs Dina Abdel Salam
Published: February 2021

The current study aimed to examine how the government departments of health in Saudi Arabia and Australia provided health advice to the public through Twitter during the COVID-19 crisis. To this end, 100 Saudi and 100 Australian tweets were analysed by usingMartínez-Flor’s (2003)advice linguistic realization strategies typology and an adapted version ofTrosborg’s (1995)coding scheme for internal modifiers. The external modifiers that emerged in the data were also examined. The results showed a general tendency to use direct advice-giving strategies among Saudis and Australians. Statistical comparisons showed that Saudis used significantly more direct advice-giving strategies and external modifiers than Australians while Australians employed significantly more conventionally indirect strategies and internal modifiers than Saudis.
Associations of physical activity, sedentary time, and diet quality with biomarkers of inflammation in children
Authors: Haapala Eero A. , Väistö Juuso , Ihalainen Johanna K. , González Claudia Tomaselli , Leppänen Marja H. , Veijalainen Aapo , Sallinen Taisa , Eloranta Aino‐Maija , Ekelund Ulf , Schwab Ursula , Brage Soren , Atalay Mustafa , Lakka Timo A.
Published: February 2021

We investigated the associations of physical activity (PA), sedentary time (ST), and diet quality with biomarkers of inflammation in 390 children (192 girls, 198 boys) aged 6–8 years. PA energy expenditure (PAEE), light PA, moderate PA (MPA), vigorous PA (VPA), moderate‐to‐vigorous PA (MVPA), and ST were assessed by combined movement and heart rate sensor. Finnish Children Healthy Eating Index was calculated using data from 4 d food records. Body fat percentage (BF%) was measured by dual‐energy X‐ray absorptiometry. High‐sensitivity C‐reactive protein (Hs‐CRP), leptin, interleukin‐6 (IL‐6), adiponectin, tumour necrosis factor‐α, and glycoprotein acetyls were measured from fasting blood samples. PAEE, MPA, VPA, and MVPA were inversely associated with hs‐CRP (β=−191 to −139, 95% CI=−0.294 to −0.024), leptin (β=−0.409 to −0.301, 95% CI=−0.499 to −0.107), IL‐6 (β=−0.136 to −0.104, 95% CI=−0.240 to −0.001) and PAEE, MPA, and MVPA were inversely associated with glycoprotein acetyls (β=−0.117 to −0.103, 95% CI=−0.213 to −0.001). ST was directly associated with hs‐CRP (β=0.170, 95% CI=0.070–0.269), leptin (β=0.355, 95% CI=0.265–0.445), and IL‐6 (β=0.105, 95% CI=0.005–0.205). VPA was inversely associated with hs‐CRP, leptin, and IL‐6 in children with higher BF% (β=−0.344 to −0.181, 95% CI=−0.477 to −0.033) but not among children with lower BF% (β=−0.007–0.033, 95% CI=−0.183–0.184). In conclusion, PA was inversely and ST directly associated with circulating levels of biomarkers of inflammation among children. Furthermore, we observed that PA was inversely associated with these biomarkers for inflammation in children with a higher BF%.

Highlights

Systemic inflammation, as indicated by increased circulating concentrations of biomarkers for inflammation, may be important in causal pathways leading to insulin resistance, sub‐clinical atherosclerosis, and eventually clinical manifestations of cardiovascular diseases.

Higher levels of physical activity and lower levels of sedentary time were associated with more favourable inflammatory profile.

Body fat percentage modified these associations and especially vigorous intensity physical activity was inversely associated with biomarkers of inflammation on children with higher body fat percentage but not in children with lower body fat percentage.
Electronic, vibrational and optical properties of two-electron atoms and ions trapped in small fullerene-like cages
Authors: Santos Leandro C , Pereira J Claudio C , Martins M Graças R , Vianna J David M
Published: February 2021

The problem of atoms and molecules caged inside fullerenes has attracted renewed interests since a new endohedral species has been experimentally realized (Bloodworth et al 2019 Angew. Chem., Int. Ed.
58 5038). In this sense, detailed theoretical studies on the spectroscopic properties of atoms and ions spatially confined in fullerene-like structures are convenient. Here we perform density functional theory (DFT) and time-dependent DFT (TDDFT) calculations to investigate the electronic, vibrational and optical properties of two-electron atomic systems, X, caged in C20 and C20H20 endohedral complexes; i.e. X@C20 and X@C20H20 (X = He, Li+, and Be++). Among these endohedral complexes, only the encapsulated Be++ ion gives rise to strongly bound complexes, whereas the encapsulated Li+ ion depends on the confining environment, and the encapsulated He atom seems to be highly repulsive in both types of cages. Our calculated excitation energies indicate that the lowest-lying singlet states strongly depend on both the nature of the endohedral atom/ion and the type of the carbon cage. Although He@C20H20 and He@C20 are obtained as repulsive complexes, they produce a small effect in the absorption spectra of the complexes. However, the presence of Li+ or Be++ in the endohedral complexes dramatically changes the electronic absorption profile of these cages. Overall, this study shows that the confinement of a Be++ ion in a very restricted space is energetically favorable, being its quantum states controllable by the confining environment.
Magnetic braille using ferrofluids
Authors: Fletcher A M , Downs J S P , Frost W , Clarke D , O’Grady K , Hirohata A
Published: February 2021

Braille provides an invaluable tactile reading system for the visually impaired. However, current braille keyboards and technology are external mechanical devices limited by their large form factor, high expense and long refresh rates. A magnetic touchpad in which braille dots are formed through a ferrofluid medium is a potential device that could promise to replace current braille technology by providing higher refresh rates, lower cost and give easy integration into current devices. In this report, work is shown towards developing a proof of concept magnetic braille touch pad, wherein a braille dot is formed using a ferrofluid by a controlled magnetic field produced by a small scale electromagnet. Attempted optimisation of braille dot formation is also undertaken, varying ferrofluid properties and electromagnet architecture to form accurate braille dots. Results show that magnetic braille touch pads are realistic devices that can be built and that there are clearly extensive opportunities for further research. In the future magnetic braille touch pads could be fully implemented into information technology devices for use by the visually impaired.
Spectroscopic ellipsometry study of CsPbBr3 perovskite thin films prepared by vacuum evaporation
Authors: Chen Chen , Wu Dan , Yuan Meng , Yu Chao , Zhang Jian , Li Chuannan , Duan Yu
Published: February 2021

CsPbX
3 (X = Cl, Br, or I) perovskite thin films can be fabricated by vacuum evaporation (VE) with high reproducibility and good film-forming ability. To design optical devices based on CsPbX
3 thin films, precise optical constants are required. As only a few optical and dielectric properties of perovskites obtained by VE have been reported, we have comprehensively studied the complex reflective index and complex dielectric function of CsPbBr3 perovskite VE films. Spectroscopic ellipsometry combined with x-ray diffraction and scanning electron microscopy revealed that the three-oscillator model precisely describes the optical constants. Therefore, the wavelength-dependent optical constants of a material can be empirically determined. Time-resolved photoluminescence of a designed CsPbBr3-light-emitting device with a Fabry–Perot cavity and agreement of its dielectric properties with reported data confirmed the existence of a microcavity effect and accurately predicted the electric field intensity distribution and cavity length. This methodology also enables the composition of perovskite to be monitored, which contains a fraction that is desirable for optimizing the performance of optical electronics.
CuO(1−x)ZnO
x
nanocomposite with broad spectrum antibacterial activity: application in medical devices and acrylic paints
Authors: Sanguramath Rajashekharayya A , Laadan Boaz , Raz Nadav , Katalan Avishay , Benarroch Daniel J , Franco Ariel
Published: February 2021

Inappropriate and disproportionate use of antibiotics have led to a rapid increase in antibacterial resistance. Therefore, alternative antibacterial strategies and solutions are sought to overcome any form of resistance to effectively treat and/or prevent the spread of infections. In this study, we report an eco-friendly and scalable approach to produce highly antibacterial CuO(1−x)ZnO
x
nanocomposite and its inclusion in medical devices and acrylic paint. Nanocomposite has nanoporous structure composed of primary nanocrystallites of Zn+2 ion doped CuO (∼15 nm) phase and pure ZnO (∼10 nm) phase. Nanocomposite exhibit strong antibacterial activity against broad spectrum of bacteria relevant to the biomedical and food industries. At 100 ppm concentration and 2 h contact period, over 5 log reduction was observed against Escherichia coli, Listeria monocytogenes, Methicillin-resistant Staphylococcus aureus and Salmonella enterica Serovar Typhimurium. Nanocomposite incorporated in medical gauze, topical formulation, and acrylic paint exhibit over 4 log reduction against S. aureus. Bactericidal activity is governed by synergetic combination of electrostatic interaction of nanocomposite with bacterial cell envelope and simultaneous generation of reactive oxygen species. Results described here would be of great benefit in developing medical devices, coatings, and paints to eradicate the growth of a wide range of bacterial pathogens.
Dimensional changes in geological sandstone caused by wetting
Authors: Burkova Irina , Ilin Eduard , Belov Alexander N , Bezryadin Alexey
Published: February 2021

Induced seismicity has received a lot of attention in recent years. This new natural phenomenon appeared as a result of active human influence on nature. The phenomenon has been detected in places of natural gas and oil recovery, and geological storage of CO2. One of the main reasons for the observed seismic activity is associated with the adsorption-induced deformation of rocks. We present experimental data and a simple model describing adsorption-induced deformation using the example of the Berea sandstone. We suggest a simplified experiment for the undergraduate university laboratory.
Calibration of an LDR-Lux meter using a smartphone
Authors: Coramik Mustafa
Published: February 2021

In this study, it is aimed to calibrate an LDR-Lux meter with a calibration setup which includes a light bulb whose brightness can be changed by using a dimmer circuit, a data acquisition card, a smartphone and a lux meter application. In order to make the measurements more accurate and to prevent errors in the measurements, a smartphone and a laptop were connected to each other via internet browser and the data obtained with physical phone experiments was displayed on the computer screen instantly. In the experimental setup, the brightness of the light was changed with the dimmer circuit and height adjustment. The data were obtained as a result of 32 experiments for different illumination values. As a result of this study, it is seen that the calibrated experimental setup works with high accuracy. With this experimental setup, it is thought that students can also easily test the inverse square law of light. The main factors that make this experimental setup effective are that, unlike other studies in the literature, a professional lux meter is not used and the cost of the developed LDR-Lux meter is very low.
Periodic patterns displace active phase separation
Authors: Thomsen Frederik J , Rapp Lisa , Bergmann Fabian , Zimmermann Walter
Published: February 2021

In this work we identify and investigate a novel bifurcation in conserved systems. This secondary bifurcation stops active phase separation in its nonlinear regime. It is then either replaced by an extended, system-filling, spatially periodic pattern or, in a complementary parameter region, by a novel hybrid state with spatially alternating homogeneous and periodic states. The transition from phase separation to extended spatially periodic patterns is hysteretic. We show that the resulting patterns are multistable, as they show stability beyond the bifurcation for different wavenumbers belonging to a wavenumber band. The transition from active phase separation to the hybrid states is continuous. Both transition scenarios are systems-spanning phenomena in particle conserving systems. They are predicted with a generic dissipative model introduced in this work. Candidates for specific systems, in which these generic secondary transitions are likely to occur, are, for example, generalized models for motility-induced phase separation in active Brownian particles, models for cell division or chemotactic systems with conserved particle dynamics.
Nonlinear simulation of TM mode free electron laser in rectangular waveguide with ion-channel
Authors: Pourali M , Hasanbeigi A , Mehdian H
Published: February 2021

By considering the propagation of TM waves in a rectangular waveguide, the radiated power of a free electron laser is calculated during beam–wave interaction in a planar wiggler. A set of self-consistent equations are derived for discerption of this system which includes some electrostatic and electromagnetic fields, equation of motions and evolution equations of amplitude and phase. The evolution equations of amplitude and phase are determined using an averaging method on the wave equation. By writing a 3D simulation code, the variation in power during electron beam propagation is investigated and then the role of various ion channel density on efficiency is examined. Numerical results show that there is a significant increase in the radiation power of TM waves in comparison with the TE waves in the proposed configuration.
Off-axis digital holography based on the Sagnac interferometer
Authors: Zhang Wanbin , Li Baosheng , Zhang Xiaoxue , Shi Chunlin
Published: February 2021

In this paper an off-axis holography is put forward based on the Sagnac interferometer. The holograms of alumina-dust aerosol particles, an United States Air Force 1951 resolution plate and paramecium were recorded in the experiment. The diffraction integral of a plane hole derived from quantum theory is illustrated by the variation of the thickness of interference fringes. We use an angular spectrum diffraction algorithm to reconstruct the recorded hologram, and the reconstructed image with high resolution is obtained after eliminating the zero-order image and conjugate image. Examples involving alumina-dust aerosols demonstrate the technique’s in situ imaging capability for complex-shaped particles over a size range of roughly 10–50 µm micrometers. The system’s feasibility is analyzed and thus confirmed.
High-efficiency single-photon router in a network with multiple outports based on chiral waveguide–emitter couplings
Authors: Wang Xin , Wu Zhen , Li Ling , Li Xiyun , Yang Wen-Xing
Published: February 2021

We propose a potentially practical scheme for constructing a quantum network based on a system where three waveguides are coupled to two two-level atoms. In the case of chiral couplings between the waveguides and atoms, we realize a directed single-photon router and the efficiency of single-photon routing reaches 100%. In addition, in this network, the photon input from one port of the channel can be fully routed to any outport of the other two channels by modulating the coupling strength of the waveguides and atoms and the frequency of the incident photon. Thus, a quantum network can be constructed based on our scheme. The influence of the ratio of chiral coupling strength on the properties of the single-photon router is also shown. We also show how the efficiency of routing is affected by system dissipation.
Quantification of microvasculature parameters based on optoacoustic angiography data
Authors: Perekatova Valeriya , Kirillin Mikhail , Subochev Pavel , Kurnikov Alexey , Khilov Aleksandr , Orlova Anna , Yuzhakova Diana , Turchin Ilya
Published: February 2021

Optoacoustic (OA) angiography allows high-contrast three-dimensional (3D) visualization of hemoglobin-containing structures ranging from micrometers to millimeters. However, due to the large amount of 3D data acquired by modern high-throughput OA systems the resulting OA vasculature images might be difficult to analyze visually. This problem is especially relevant for monitoring of angiogenesis of experimental tumors, which blood vessels tend to be smaller and more tortuous compared to vasculature of healthy tissue. In this paper a novel algorithm for OA image processing is proposed to quantify vessel structure parameters automatically. The algorithm is based on creation of vasculature graphs which parameters (lengths of branches, number of branches, etc) can serve as a numerical characterization of vasculature: vessel density, vessel length, etc. The results of testing the developed algorithm on numerical simulation phantoms and in vivo OA images of tumor models in a mouse demonstrate a statistically significant difference of all the extracted parameters for tumor and normal tissue. The results show a high potential of the proposed approach for OA angiography in different applications including clinical and experimental oncology.