bluuebunny/crossref_metadata_2025 huggingface dataset:
A facile one‐step synthesis of chromeno[4,3‐b]pyridine derivatives promoted by niobium pentachloride
Authors: Oshiro Paula B. , Bregadiolli Bruna A. , da Silva‐Filho Luiz C.
Published: April 2020

Chromenes are part of an important class of heterocyclic compounds, natural or synthetic, and have many biological and chemical applications. Among them, chromenopyridines has arisen as a promising material for pharmacological applications. In this work is described a simple and cost‐effective method to synthesize chromeno[4,3‐b]pyridine derivatives from multicomponent reaction between 4‐aminocoumarin, benzaldehyde derivatives, and ethyl benzoylacetates catalyzed by niobium pentachloride. The new method provides good yields with reasonable reaction times, under mild reaction conditions.
Prospective Study on Energy Expenditure in Patients With Severe Burns
Authors: Guo Fengmei , Zhou Hua , Wu Jian , Huang Yingzi , Lv Guozhong , Wu Yunfu , Qiu Haibo , Xu Yuan , Yang Yi
Published: April 2020

Background

Nutrition therapy is recognized as one of the most significant treatment aspects for burn patients. However, data were limited regarding the actual nutrition practices in patients with severe burn injury. This study aims to explore the measured energy expenditure (MEE) changes in severe burn patients and to evaluate the precision of commonly used predictive formulas for estimating predictive energy expenditure (PEE) in burn patients.

Methods

A prospective multicenter trial was conducted in the intensive care units in the hospitals enrolling the severely burned patients. Data on MEE and PEE were collected and analyzed.

Results

Forty‐three patients were enrolled from 3 hospitals. All the patients had severe burns. MEE was measured by metabolic cart, and the MEE on the seventh day after severe burns was as high as 65 kcal/kg, which was 267% of the basal metabolic rate. The presence of hypermetabolism was sustained throughout the 21‐day afterburn and decreased gradually to 34 kcal/kg thereafter until 4 weeks after injury. Wound percentage after skin‐grafting therapy, time course of burn injury, the existence of severe sepsis, and blood infection were significantly associated with higher MEE. Compared with PEE and MEE, Toronto formula could estimate patients’ energy requirements with more accuracy; Curreri and Pennisi formula both significantly overestimated the patient's energy expenditure, whereas underestimation occurred with the Harris‐Benedict formula.

Conclusions

Severe burn patients were hypermetabolic at the early stage and sustained this status over a long time. The Toronto formula was the unbiased method to predict energy expenditure.
The Art of Asking Questions: Unlocking the Power of a Coach’s Language
Authors: Hudson Alida K. , Pletcher Bethanie C.
Published: April 2020

The authors aim to build awareness of questioning strategies and techniques in specialized literacy professionals (SLPs), specifically those in a literacy coach role. Whereas questioning is a technique that may promote reflective thinking in teachers, the authors note, providing examples and solving problems for teachers may come more naturally to SLPs than the use of questioning to probe reflection. Further, SLPs often express the desire to find and use the language of coaching conversations so they can promote deep reflection and critical analysis in teachers through one‐on‐one coaching conversations. To help SLPs build their coaching discourse, the authors share various types of questions and prompts that align with each category. Implications for SLPs, school districts, and university programs responsible for preparing SLPs are also addressed.
The Analyses of Luminescent Properties and Structure of the Tetragonal Phase of Y2WO6:Eu3+ doped Phosphor
Authors: Castillo Rodrigo , Espinoza Darío , Conejeros Sergio , Llanos Jaime
Published: April 2020

The structural, electronic and luminescent properties of the tetragonal phase of Y2WO6 phosphors doped with different amounts of Eu3+ have been studied. All samples were synthesized via solid‐state methods, using NaCl as mineralizer. Through Rietveld refinement was found that the Eu3+ cations only occupy the Y1 (2c) sites of the host‐matrix. The thermal stability of the undoped sample was investigated using simultaneous TG‐DSC thermal analyses. The SEM analysis revealed that the doped and the undoped samples have tendency to form microcrystals with smooth surfaces and in both cases it is possible to observe some agglomerates of nanoparticles. Periodic Density Functional Theory calculations (DFT) were carried out to investigate the electronic properties of the undoped material; these results show good agreement with the experimental ones. The emission spectra of all doped‐samples are dominated by the electric dipole transition (ED) 5D0 → 7F2 located at 613 nm, which indicates that the Eu3+ ions are located in non‐centrosimetric sites in the host‐structure.
GPU Supported Simulation of Transition-Edge Sensor Arrays
Authors: Lorenz M. , Kirsch C. , Merino-Alonso P. E. , Peille P. , Dauser T. , Cucchetti E. , Smith S. J. , Wilms J.
Published: April 2020

We present numerical simulations of full transition-edge sensor (TES) arrays utilizing graphical processing units (GPUs). With the support of GPUs, it is possible to perform simulations of large pixel arrays to assist detector development. Comparisons with TES small-signal and noise theory confirm the representativity of the simulated data. In order to demonstrate the capabilities of this approach, we present its implementation in , a simulator for the X-ray Integral Field Unit, a cryogenic X-ray spectrometer on board the future Athena X-ray observatory.
Thirty Years of Science, Technology, and Academia in Disaster Risk Reduction and Emerging Responsibilities
Authors: Shaw Rajib
Published: April 2020

The 1990 initiation of the International Decade for Natural Disaster Reduction marked its 30th year in 2019. The three decades since then have seen significant developments in science and technology and their incorporation into the decision making in the field of disaster risk reduction. The disasters that have occurred during that time have enhanced the importance of the field, and new research and innovations have evolved. This article summarizes this evolution through the review of specific milestones. While the Sendai Framework for Disaster Risk Reduction 2015–2030 provides opportunities for synergies with the sustainable development agenda, the science and technology communities have also changed their roles from advisory to co-designing and co-delivering solutions. Higher education plays an important role in developing new generations of professionals, and the role of thematic incubation in higher education institutions is highlighted along with the development of the professional society in disaster risk reduction. The evolution from Society 4.0 (information age) to Society 5.0 will see an enhanced role of the technology-driven approach in disaster risk reduction, while traditional knowledge and indigenous technologies still remain valid for society. Scientists and science communities need to be more sensitive to changing the “last mile” concept to “first mile” thinking with respect to the users’ needs and perspectives.
Turkey’s EEC membership as a canvas of struggle for identity: The NSP versus the JP
Authors: Can Serra
Published: April 2020

This article uncovers the relationship between the intra-paradigm power struggle of two rival political parties in 1970s Turkey and their identity formations. Given the economy-laden context of Turkish–European relations in the 1970s, the (re)production of Europe as an identificatory reference between the National Salvation Party (NSP) and the Justice Party (JP) is of special interest. This investigation will help shed light on how the power relations—that both actors were situated in—can be mirrored through their struggle for identity. Moreover, will it contribute to highlighting the functionality of foreign policy in the production of identity. In analytical terms, this study borrows case-restricted concepts from the post-structuralist theory of international relations, and gathers its case data from the 1970s National Assembly records.
Direct Observation of Winter Meltwater Drainage From the Greenland Ice Sheet
Authors: Pitcher Lincoln H. , Smith Laurence C. , Gleason Colin J. , Miège Clément , Ryan Jonathan C. , Hagedorn Birgit , van As Dirk , Chu Winnie , Forster Richard R.
Published: April 2020

Meltwater runoff from the Greenland Ice Sheet (GrIS) significantly contributes to sea level rise and is the dominant driver of enhanced mass loss. While most melt occurs during summer, little is known about its seasonal and/or interannual retention within the GrIS. Here, we document evidence of runoff during winter, ~4 months after summer melt. Ground‐penetrating radar and borehole surveys in the proglacial Isortoq River reveal slowly flowing water beneath >0.5 m of river ice. Geochemical analysis of this water indicates previous contact with the ice sheet bed. Comparable surveys in proglacial rivers draining four neighboring catchments found no winter drainage, despite a brief surface melt event ~10 days prior. We attribute the observed runoff to residual meltwater storage and release enabled by a >600 m deep trough beneath Isunguata Sermia, but not neighboring glaciers. We conclude that the GrIS bed can stay wet and drain small amounts of meltwater year‐round.
Mental Health Literacy of Maternal and Paternal Postnatal Depression in a Community Sample of Romanian Adults
Authors: Swami Viren , Vintila Mona , Goian Cosmin , Tudorel Otilia , Bucur Venera
Published: April 2020

Postnatal depression affects a large proportion of Romanian parents, but no existing research has examined knowledge of postnatal depression in Romanian adults. To rectify this, we examined the ability of Romanian adults to correctly identify cases of maternal and paternal postnatal depression, as well as attitudes toward cases of postnatal depression. A total of 1,248 Romanian adults were presented with vignettes describing cases of maternal or paternal postnatal depression. Based on the vignettes, participants were asked to report if they thought anything was wrong with the targets and, if so, to describe what they thought was wrong. Participants also rated the targets on several attitudinal dimensions. Participants were more likely to indicate that something was wrong when the target was female (67.9%) compared with male (46.4%). Of those who believed something was wrong, 57.7% of participants correctly described the female target as experiencing postnatal depression, but only 37.1% did so for the male target. Women held significantly more positive attitudes toward the targets than men, particularly when the target was female. Mental health literacy of postnatal depression appears to be poor in Romanian adults compared with other national groups, especially in the case of paternal postnatal depression.
A call for refining the role of humic-like substances in the oceanic iron cycle
Authors: Whitby Hannah , Planquette Hélène , Cassar Nicolas , Bucciarelli Eva , Osburn Christopher L. , Janssen David J. , Cullen Jay T. , González Aridane G. , Völker Christoph , Sarthou Géraldine
Published: April 2020

Primary production by phytoplankton represents a major pathway whereby atmospheric CO2 is sequestered in the ocean, but this requires iron, which is in scarce supply. As over 99% of iron is complexed to organic ligands, which increase iron solubility and microbial availability, understanding the processes governing ligand dynamics is of fundamental importance. Ligands within humic-like substances have long been considered important for iron complexation, but their role has never been explained in an oceanographically consistent manner. Here we show iron co-varying with electroactive humic substances at multiple open ocean sites, with the ratio of iron to humics increasing with depth. Our results agree with humic ligands composing a large fraction of the iron-binding ligand pool throughout the water column. We demonstrate how maximum dissolved iron concentrations could be limited by the concentration and binding capacity of humic ligands, and provide a summary of the key processes that could influence these parameters. If this relationship is globally representative, humics could impose a concentration threshold that buffers the deep ocean iron inventory. This study highlights the dearth of humic data, and the immediate need to measure electroactive humics, dissolved iron and iron-binding ligands simultaneously from surface to depth, across different ocean basins.
Difference in spectral power density of sleep EEG between patients with simple snoring and those with obstructive sleep apnoea
Authors: Kang Jae Myeong , Kim Seon Tae , Mariani Sara , Cho Seo-Eun , Winkelman John W. , Park Kee Hyung , Kang Seung-Gul
Published: April 2020

Patients with simple snoring (SS) often complain of poor sleep quality despite a normal apnoea-hypopnoea index (AHI). We aimed to identify the difference in power spectral density of electroencephalography (EEG) between patients with SS and those with obstructive sleep apnoea (OSA). We compared the absolute power spectral density values of standard EEG frequency bands between the SS (n = 42) and OSA (n = 129) groups during the non-rapid eye movement (NREM) sleep period, after controlling for age and sex. We also analysed partial correlation between AHI and the absolute values of the EEG frequency bands. The absolute power spectral density values in the beta and delta bands were higher in the OSA group than in the SS group. AHI also positively correlated with beta power in the OSA group as well as in the combined group (OSA + SS). In conclusion, higher delta and beta power during NREM sleep were found in the OSA group than in the SS group, and beta power was correlated with AHI. These findings are microstructural characteristics of sleep-related breathing disorders.
Effect of mild nanoscopic confinement on the dynamics of ionic liquids
Authors: Noferini Daria , Holderer Olaf , Frielinghaus Henrich
Published: April 2020

X-ray diffraction and neutron spectroscopy provide new insights into the effect of confinement on the structure and diffusion of ionic liquids.
Selective cell propagation via micropatterning of a thermally-activated hydrogel
Authors: Chiu Jeffrey C. Y. , Teodoro Joyce A. , Lee Jeong Hyun , Matthews Kerryn , Duffy Simon P. , Ma Hongshen
Published: April 2020

Inverse gelation of methylcellulose enables hydrogel micropatterning to selectively propagate cells identified by microscopy.
High-resolution probing of early events in amyloid-β aggregation related to Alzheimer's disease
Authors: Sahoo Bikash R. , Cox Sarah J. , Ramamoorthy Ayyalusamy
Published: April 2020

High-resolution structure elucidation of Alzheimer's amyloid-β oligomer is crucial to delineate its pathological phenotype. NMR provides atomic-resolution details of amyloid-β oligomer that could aid in the development of structure-based therapeutics.
Giant optical absorption and ferroelectric polarization of BiCoO2S perovskite oxysulfide by first principles prediction
Authors: Wei Lijing , Li Changliang , Guo Jianxin , Guan Li , Wang Yinglong , Liu Baoting
Published: April 2020

Obtaining an ideal ferroelectric photovoltaic (FE-PV) materials BiCoO2S with a giant absorption coefficient and ferroelectric polarization.
Effect of magnetic anisotropy on direct chiral discrimination in paramagnetic NMR spectroscopy
Authors: Calvello Simone , Soncini Alessandro
Published: April 2020

We have studied the effect of thermally populated crystal field states on room temperature chiral discrimination in NMR spectroscopy.
Low-level detection of water in polar aprotic solvents using an unusually fluorescent spirocyclic rhodamine
Authors: Yuvaraj Palani , Ajantha Joseph , Easwaramoorthi Shanmugam , Rao Jonnalagadda Raghava
Published: April 2020

Detection of trace amount of water in polar aprotic solvents (acetonitrile) by novel fluorescent spirocyclic rhodamine (sDRh).
Schützen Östrogene Frauen vor der Fettleber?
Authors: Kahl Sabine , Hohlfeld Thomas
Published: April 2020

Die nichtalkoholische Fettlebererkrankung (NAFLD) ist die häufigste chronische Lebererkrankung in Europa und den USA, eine der zukünftig führenden Ursachen für Lebertransplantationen und eng assoziiert mit erhöhter kardiovaskulärer und leberbezogener Mortalität. Insbesondere Patienten mit Typ-2-Diabetes haben ein hohes Risiko für die Entwicklung und Progression der NAFLD. Männer sind häufiger von einer NAFLD betroffen als Frauen. Geschlecht und Sexualhormonspiegel sind entscheidende Faktoren, welche zur biologischen Varianz von Erkrankungen beitragen und Östrogene spielen im Zusammenhang mit der Pathogenese und Progression der NAFLD eine entscheidende Rolle. Möglicherweise könnten bzw. sollten die zukünftigen Therapien der NAFLD geschlechtsspezifische Aspekte beinhalten auf dem Weg hin zur Präzisionsmedizin. Die Evidenz aus klinischen Studien ist allerdings nicht ausreichend – auch deshalb, weil geschlechtsspezifische Unterschiede in (prä)klinischen Studien bislang oft nur unzureichend erfasst wurden.
Repair of Acute Type-A Aortic Dissection in the Present Era: Outcomes and Controversies
Authors: Moeller Ellie , Nores Marcos , Stamou Sotiris C.
Published: April 2020

Acute Type-A aortic dissection (AAAD) remains a surgical emergency with a relatively high operative mortality despite advances in medical and surgical management over the past three decades. In spite of the severity of disease, there is a paucity of studies reviewing key controversies surrounding AAAD repair and management. A systematic literature search was performed using Cochrane review and PubMed bibliography review. Abstracts were first reviewed for general pertinence and then articles were reviewed in full. Literature review indicates that use of moderate hypothermia and antegrade cerebral perfusion is a safe alternative to deep hypothermia. In hemodynamically stable patients, axillary cannulation may be substituted for femoral cannulation. With regard to the technical aspects of repair, preserving the aortic root whenever possible and performing the distal anastomosis with the open distal technique rather than with the clamp on is the preferred approach. In patients with a patent false lumen, close monitoring is indicated. As demonstrated by the literature, significant improvement of early and late mortality over the past years has occurred in patients presenting with AAAD. Repair of acute Type-A aortic dissection remains a challenge with high operative mortality; however, improvement of surgical techniques and management have resulted in improvement of early and late clinical outcomes.
Low temperature phonon studies and evidence of structure–spin correlations in MnV2O4
Authors: Singha Mrittika , Paul Barnita , Gupta Rajeev
Published: April 2020

We report here, temperature dependent Raman spectroscopic measurements on polycrystalline MnV2O4 over the temperature range of 10–300 K. The main aim of this study is to investigate the spin–phonon correlations across the magnetic and structural transition temperatures in this system. Temperature dependent magnetization measurements combined with the low temperature Raman study show the existence of structural changes in MnV2O4 across the two successive phase transitions. Anomalous changes in line shape parameters in some of the Raman modes are observed during temperature dependent Raman measurements, indicating the presence of spin–phonon coupling. A significantly high spin–phonon coupling strength of 5.9 cm−1 suggests alteration of spin dynamics across magnetic transition temperature, TM (57 K).
Possible mitigation of tokamak plasma–surface interactions using thermionic divertor plates with inverse sheaths
Authors: Campanell M. D.
Published: April 2020

Recent studies demonstrate that when a plasma-facing surface emits a sufficient flux of electrons, it will form an inverse sheath. Here, we consider a possibility of using thermionic target plates with inverse sheaths as an innovative divertor operating scenario. We derive an electron heat flux boundary condition for inverse sheaths and show that for given power exhaust into a tokamak scrape-off-layer, an inverse sheath leads to a much lower target plasma electron temperature than a conventional sheath. Low enough target plasma temperatures for radiative divertor detachment could therefore be achieved using inverse sheaths instead of the usual need to inject neutral atoms that compromise the core plasma. Other advantages of inverse sheath detachment over conventional sheath operating scenarios include (a) ion impact energies are as low as possible, minimizing sputtering and tritium implantation, (b) surface recombination heat flux is reduced due to ion flux reduction, and (c) arcs are inhibited due to the sign of the surface electric field. This paper outlines the basic properties of inverse sheath detachment and considers the feasibility of implementation. We offer recommendations for future modeling efforts needed to better understand the effects of thermionic emission in tokamaks and whether inverse sheaths present a viable divertor solution.
Phosphorus-doped polymeric carbon nitride nanosheets for enhanced photocatalytic hydrogen production
Authors: Zhu Yukun , Li Junzhi , Cao Junming , Lv Chunxiao , Huang Guiqing , Zhang Gaolian , Xu Yan , Zhang Shuchao , Meng Pingping , Zhan Tianrong , Yang Dongjiang
Published: April 2020

Photocatalytic hydrogen production by water splitting is one of the most effective strategies for solar energy conversion and utilization. The metal-free polymeric carbon nitride (CN) has been widely used as an efficient photocatalyst for the photocatalytic hydrogen evolution reaction (HER). However, to date, the solar to hydrogen conversion efficiency of the CN-based photocatalysts is still low. Herein, to boost the photocatalytic activity of CN, controllable phosphorus atoms were introduced to form P-doped CN (PCN) via an evacuated ampoule calcination strategy. Compared with bare CN, the optimized PCN exhibits remarkably enhanced photocatalytic HER activity, with the HER rate up to 261.2 µmol h−1 and 171.6 µmol h−1 under the simulated solar light and visible-light illumination, respectively. It was revealed that the boosted photocatalysis for HER is mainly ascribed to the P dopants that can synergetically increase the visible-light absorption and facilitate the charge transfer process. This present work highlights improving the photocatalytic energy conversion efficiency by controllable tuning of the heteroatom doping degree in photocatalysts.
Solvation at metal/water interfaces: An ab initio molecular dynamics benchmark of common computational approaches
Authors: Heenen Hendrik H. , Gauthier Joseph A. , Kristoffersen Henrik H. , Ludwig Thomas , Chan Karen
Published: April 2020

Determining the influence of the solvent on electrochemical reaction energetics is a central challenge in our understanding of electrochemical interfaces. To date, it is unclear how well existing methods predict solvation energies at solid/liquid interfaces, since they cannot be assessed experimentally. Ab initio molecular dynamics (AIMD) simulations present a physically highly accurate, but also a very costly approach. In this work, we employ extensive AIMD simulations to benchmark solvation at charge-neutral metal/water interfaces against commonly applied continuum solvent models. We consider a variety of adsorbates including *CO, *CHO, *COH, *OCCHO, *OH, and *OOH on Cu, Au, and Pt facets solvated by water. The surfaces and adsorbates considered are relevant, among other reactions, to electrochemical CO2 reduction and the oxygen redox reactions. We determine directional hydrogen bonds and steric water competition to be critical for a correct description of solvation at the metal/water interfaces. As a consequence, we find that the most frequently applied continuum solvation methods, which do not yet capture these properties, do not presently provide more accurate energetics over simulations in vacuum. We find most of the computed benchmark solvation energies to linearly scale with hydrogen bonding or competitive water adsorption, which strongly differ across surfaces. Thus, we determine solvation energies of adsorbates to be non-transferable between metal surfaces, in contrast to standard practice.
Inverse methods for design of soft materials
Authors: Sherman Zachary M. , Howard Michael P. , Lindquist Beth A. , Jadrich Ryan B. , Truskett Thomas M.
Published: April 2020

Functional soft materials, comprising colloidal and molecular building blocks that self-organize into complex structures as a result of their tunable interactions, enable a wide array of technological applications. Inverse methods provide a systematic means for navigating their inherently high-dimensional design spaces to create materials with targeted properties. While multiple physically motivated inverse strategies have been successfully implemented in silico, their translation to guiding experimental materials discovery has thus far been limited to a handful of proof-of-concept studies. In this perspective, we discuss recent advances in inverse methods for design of soft materials that address two challenges: (1) methodological limitations that prevent such approaches from satisfying design constraints and (2) computational challenges that limit the size and complexity of systems that can be addressed. Strategies that leverage machine learning have proven particularly effective, including methods to discover order parameters that characterize complex structural motifs and schemes to efficiently compute macroscopic properties from the underlying structure. We also highlight promising opportunities to improve the experimental realizability of materials designed computationally, including discovery of materials with functionality at multiple thermodynamic states, design of externally directed assembly protocols that are simple to implement in experiments, and strategies to improve the accuracy and computational efficiency of experimentally relevant models.
Toward reliable high performing organic solar cells: Molecules, processing, and monitoring
Authors: Vijayan Raaghesh , Azeez Abdul , Narayan K. S.
Published: April 2020

A steady surge in device efficiencies of organic solar cells (OSCs) along with improvement in associated features, such as stability and facile processing methods, is expected to provide a realistic, feasible commercial option. The introduction of high performing donor and acceptor molecules along with tailored buffer layers has provided the impetus for the resurgence of this field. Further options of ternary and tandem architectures of these OSC systems should push this technology to competitive levels. A major hurdle, which is expected when these devices are evaluated for long-term performance in all weather conditions, is the level of degradation. We examine and address these stability-limiting factors in this perspective article. Modifications in microstructure/morphology and interfaces with time and energy levels defining the molecules form some of the critical intrinsic degradation pathways. Various strategies that have been used to limit the associated pathways of degradation of the active layer will be discussed. One such strategy is electric field-assisted thermal annealing treatment, which concomitantly also brings in a favorable vertical phase segregated active layer morphology. We also emphasize the utility of photocurrent noise measurements to monitor the level of degradation and possibly forecast the trajectory of long-term performance of OSCs.
Aspects of the synthesis of thin film superconducting infinite-layer nickelates
Authors: Lee Kyuho , Goodge Berit H. , Li Danfeng , Osada Motoki , Wang Bai Yang , Cui Yi , Kourkoutis Lena F. , Hwang Harold Y.
Published: April 2020

The recent observation of superconductivity in Nd0.8Sr0.2NiO2 calls for further investigation and optimization of the synthesis of this infinite-layer nickelate structure. Here, we present our current understanding of important aspects of the growth of the parent perovskite compound via pulsed laser deposition on SrTiO3 (001) substrates and the subsequent topotactic reduction. We find that to achieve single-crystalline, single-phase superconducting Nd0.8Sr0.2NiO2, it is essential that the precursor perovskite Nd0.8Sr0.2NiO3 thin film is stabilized with no visible impurity phases; in particular, a Ruddlesden–Popper-type secondary phase is often observed. We have further investigated the evolution of the soft-chemistry topotactic reduction conditions to realize full transformation to the infinite-layer structure with no film decomposition or formation of other phases. We find that capping the nickelate film with a subsequent SrTiO3 layer provides an epitaxial template to the top region of the nickelate film, much like the substrate. Thus, for currently optimized growth conditions, we can stabilize superconducting single-phase Nd0.8Sr0.2NiO2 (001) epitaxial thin films up to ∼10 nm.
Aluminum nitride two-dimensional-resonant-rods
Authors: Zhao Xuanyi , Colombo Luca , Cassella Cristian
Published: April 2020

In the last few decades, bulk-acoustic-wave filters have been essential components of 3G-to-4G radios. These devices rely on the high electromechanical coupling coefficient (kt2 ∼ 7%), attained by aluminum nitride (AlN) film-bulk-acoustic-resonators (FBARs), to achieve a wideband and low-loss frequency response. As the resonance frequency of FBARs is set by their thickness, the integration of multiple FBARs, to form filters, can only be attained through the adoption of frequency tuning fabrication steps, such as mass loading or trimming. However, as the ability to reliably control these steps significantly decays for thinner (or higher frequency) FBARs, manufacturing FBAR-based filters, addressing the needs of emerging IoT and 5G applications, is becoming more and more challenging. Consequently, there is a quest for new acoustic resonant components, simultaneously exhibiting high-kt2 and a lithographic frequency tunability. In this work, a novel class of AlN resonators is presented. These radio frequency devices, labeled as two-dimensional-resonant-rods (2DRRs), exploit, for the first time, the unconventional acoustic behavior exhibited by a forest of locally resonant rods, built in the body of a profiled AlN layer that is sandwiched between a bottom un-patterned metal plate and a top metallic grating. 2DRRs exhibit unexplored modal features that make them able to achieve high-kt2, a significant lithographic frequency tunability, and a relaxed lithographic resolution, while relying on an optimal AlN crystalline orientation. The operation of 2DRRs is discussed, in this work, by means of analytical and finite-element-methods. The measured performance of the first fabricated 2DRR, operating around 2.4 GHz and showing a kt2 in excess of 7.4%, is also reported.
MST4 kinase suppresses gastric tumorigenesis by limiting YAP activation via a non-canonical pathway
Authors: An Liwei , Nie Pingping , Chen Min , Tang Yang , Zhang Hui , Guan Jingmin , Cao Zhifa , Hou Chun , Wang Wenjia , Zhao Yun , Xu Huixiong , Jiao Shi , Zhou Zhaocai
Published: April 2020

Hyperactivation of YAP has been commonly associated with tumorigenesis, and emerging evidence hints at multilayered Hippo-independent regulations of YAP. In this study, we identified a new MST4–YAP axis, which acts as a noncanonical Hippo signaling pathway that limits stress-induced YAP activation. MST4 kinase directly phosphorylated YAP at Thr83 to block its binding with importin α, therefore leading to YAP cytoplasmic retention and inactivation. Due to a consequential interplay between MST4-mediated YAP phospho-Thr83 signaling and the classical YAP phospho-Ser127 signaling, the phosphorylation level of YAP at Thr83 was correlated to that at Ser127. Mutation of T83E mimicking MST4-mediated alternative signaling restrained the activity of both wild-type YAP and its S127A mutant mimicking loss of classical Hippo signal. Depletion of MST4 in mice promoted gastric tumorigenesis with diminished Thr83 phosphorylation and hyperactivation of YAP. Moreover, loss of MST4–YAP signaling was associated with poor prognosis of human gastric cancer. Collectively, our study uncovered a noncanonical MST4–YAP signaling axis essential for suppressing gastric tumorigenesis.
Optical and electrical optimization of all-perovskite pin type junction tandem solar cells
Authors: Soldera Marcos , Koffman-Frischknecht Alejandro , Taretto Kurt
Published: April 2020

A definitive breakthrough of perovskite solar cells towards large scale industrialization is believed to be the demonstration of higher efficiencies than conventional silicon technology, suggesting the exploration of perovskite tandem cell configurations. Since high efficiency tandem solar cells require careful optimization of photoactive as well as contact and additional functional layers, we propose an optical-electrical model to obtain the optimum layer thicknesses and the attainable electrical output parameters of two-terminal perovskite-perovskite tandem solar cells. The optical model takes into account the coherent propagation of light through the layer stack comprising two perovskite semiconductors and the corresponding contact layers, while the electrical model assumes two series-connected analytical current/voltage equations for pin solar cells. This model allows to assess the impact of the main physical parameters on each perovskite layer without requiring the high specificity needed in more rigorous numerical simulations. Efficiencies above 34% are predicted considering available perovskites with non-optimum bandgap and contact materials already proven in efficient laboratory solar cells. The requisite to attain such efficiencies is that recombination at the interfaces between the perovskite and contact materials is kept low in both bottom and top cells. Furthermore, within the assumption of non-optimum bandgaps of currently available perovskites, the simulation results suggest that efficiencies around 37% are possible when adopting contact materials with smaller absorption, more adequate refraction indices, and lower resistivity.
Integrating Sleep, Physical Activity, and Diet Quality to Estimate All-Cause Mortality Risk: A Combined Compositional Clustering and Survival Analysis of the National Health and Nutrition Examination Survey 2005–2006 Cycle
Authors: del Pozo Cruz Borja , McGregor Duncan E , del Pozo Cruz Jesús , Buman Matthew P , Palarea-Albaladejo Javier , Alfonso-Rosa Rosa M , Chastin Sebastien F M
Published: April 2020

We aimed to compare all-cause mortality risk across clusters of adults ≥50 years of age (n = 1,035) with common lifestyle behaviors patterns, enrolled in the US National Health and Nutrition Examination Survey (2005–2006). Log-ratio coordinates of 24-hour movement pattern and z scores of diet quality were used as input into a model-based clustering analysis. A Cox regression model was fitted to ascertain the all-cause mortality risk associated with each cluster. Participants were clustered into 4 groups: 1) a group characterized by a better physical activity profile and longer sleep duration coupled with an average diet quality (cluster 1); 2) a group with the poorest activity profile and shortest sleep but also the best diet quality (cluster 2); 3) another group featuring lower levels of activity of either intensity and higher levels of sedentary behavior and also a poor diet quality score (cluster 3); and 4) a group with an average diet quality and the best activity profile in the sample (cluster 4). A combination of a poorer diet and activity profile increased the prospective risk of all-cause mortality. Our findings emphasize the importance of considering the combination of diet quality and 24-hour movement patterns when developing interventions to reduce the risk of premature mortality.
Performance-Based Rankings and School Quality
Authors: Herresthal Claudia
Published: April 2020

I study students’ inferences about school quality from performance-based rankings in a dynamic setting. Schools differ in location and unobserved quality; students differ in location and ability. Short-lived students observe a school ranking as a signal about schools’ relative qualities, but this signal also depends on the abilities of schools’ past intakes. Students apply to schools, trading off expected quality against proximity. Oversubscribed schools select applicants based on an admission rule. In steady-state equilibrium, I find that rankings are more informative if more able applicants are given priority in admissions or if students care less about distance to school.
Likelihood Ratios as Value Proposition for Diagnostic Laboratory Tests
Authors: Fierz Walter , Bossuyt Xavier
Published: April 2020

The clinical and health economic value of clinical laboratory diagnostics has been debated increasingly in recent years without resulting in practical recommendations for measuring the effectiveness of diagnostic tests. One way to achieve such a goal could be to enrich the mere data of laboratory test results with additional information about their likelihood ratios for diagnosis. The diagnostic significance of test results can be judged subjectively based on the experience of the treating physician or expressed objectively in the form of likelihood ratios. The provision of likelihood ratios by the laboratory would increase the impact of laboratory diagnostics in healthcare and thus have positive economic value. Consequently, likelihood ratios should be taken into account in reimbursement strategies.
Mortality for robotic- versus video-assisted lobectomy treated stage I non-small cell lung cancer patients
Authors: Cui Yong , Grogan Eric L , Deppen Stephen A , Wang Fei , Massion Pierre P , Bailey Christina E , Zheng Wei , Cai Hui , Shu Xiao-Ou
Published: April 2020

Background

To address the United States Food & Drug Administration’s recent safety concern on robotic surgery procedures, we compared short- and long-term mortality for stage I non-small cell lung cancer (NSCLC) patients treated by robotic-assisted thoracoscopic surgical lobectomy (RATS-L) versus video-assisted thoracoscopic surgical lobectomy (VATS-L).

Methods

From the National Cancer Database, we identified 18,908 stage I NSCLC patients who underwent RATS-L or VATS-L as the primary operation from 2010 to 2014. Cox proportional hazards models were used to estimate hazard ratios (HRs) for short- and long-term mortality using unmatched and propensity score-matched analyses. All statistical tests were two-sided.

Results

Patients treated by RATS-L had higher 90-day mortality than those with VATS-L (6.6% vs. 3.8%; P=.03) if conversion to open thoracotomy occurred. After excluding first-year observation, multiple regression analyses showed RATS-L was associated with increased long-term mortality, compared to VATS-L, in cases with tumor size ≤20 mm: HRs were 1.33 (95%CI: 1.15-1.55), 1.36 (95%CI: 1.17-1.58) and 1.33 (95%CI: 1.11-1.61) for unmatched, N:1 matched and 1:1 matched analyses, respectively, in the intention-to-treat analysis. Among patients without conversion to an open thoracotomy, the respective HRs were 1.19 (95%CI: 1.10-1.29), 1.19 (95%CI: 1.10-1.29) and 1.17 (95%CI: 1.06-1.29). Similar associations were observed when follow-up time started 18- or 24-months post-surgery. No statistically significant mortality difference was found for patients with tumor size >20 mm. These associations were not related to case volume of VATS-L/RATS-L performed at treatment institutes.

Conclusions

Patients with small (≤20 mm) stage I NSCLC treated with RATS-L had statistically significantly higher long-term mortality risk than VATS-L after one-year post-surgery.
Classifying CMB time-ordered data through deep neural networks
Authors: Rojas Felipe , Maurin Loïc , Dünner Rolando , Pichara Karim
Published: April 2020

The Cosmic Microwave Background (CMB) has been measured over a wide range of multipoles. Experiments with arcminute resolution like the Atacama Cosmology Telescope (ACT) have contributed to the measurement of primary and secondary anisotropies, leading to remarkable scientific discoveries. Such findings require careful data selection in order to remove poorly behaved detectors and unwanted contaminants. The current data classification methodology used by ACT relies on several statistical parameters that are assessed and fine-tuned by an expert. This method is highly time-consuming and band or season-specific, which makes it less scalable and efficient for future CMB experiments. In this work, we propose a supervised machine learning model to classify detectors of CMB experiments. The model corresponds to a deep convolutional neural network. We tested our method on real ACT data, using the 2008 season, 148 GHz, as training set with labels provided by the ACT data selection software. The model learns to classify time-streams starting directly from the raw data. For the season and frequency considered during the training, we find that our classifier reaches a precision of 99.8 per cent. For 220 and 280 GHz data, season 2008, we obtained 99.4 per cent and 97.5 per cent of precision, respectively. Finally, we performed a cross-season test over 148 GHz data from 2009 and 2010 for which our model reaches a precision of 99.8 per cent and 99.5 per cent, respectively. Our model is about 10x faster than the current pipeline, making it potentially suitable for real-time implementations.
Characterizing the dynamo in a radiatively inefficient accretion flow
Authors: Dhang Prasun , Bendre Abhijit , Sharma Prateek , Subramanian Kandaswamy
Published: April 2020

We explore the magneto-rotational instability (MRI)-driven dynamo in a radiatively inefficient accretion flow (RIAF) using the mean field dynamo paradigm. Using singular value decomposition (SVD) we obtain the least-squares fitting dynamo coefficients α and γ by comparing the time series of the turbulent electromotive force and the mean magnetic field. Our study is the first one to show the poloidal distribution of these dynamo coefficients in global accretion flow simulations. Surprisingly, we obtain a high value of the turbulent pumping coefficient γ, which transports the mean magnetic flux radially outwards. This would have implications for the launching of magnetized jets that are produced efficiently in presence a large-scale poloidal magnetic field close to the compact object. We present a scenario of a truncated disc beyond the RIAF where a large-scale dynamo-generated poloidal magnetic field can aid jet launching close to the black hole. Magnitude of all the calculated coefficients decreases with radius. Meridional variations of αϕϕ, responsible for toroidal to poloidal field conversion, is very similar to that found in shearing box simulations using the ‘test field’ (TF) method. By estimating the relative importance of α-effect and shear, we conclude that the MRI-driven large-scale dynamo, which operates at high latitudes beyond a disc scale height, is essentially of the α − Ω type.
Blazar variability power spectra from radio up to TeV photon energies: Mrk 421 and PKS 2155−304
Authors: Goyal Arti
Published: April 2020

We present the results of the power spectral density (PSD) analysis for the blazars Mrk 421 and PKS 2155−304, using good-quality, densely sampled light curves at multiple frequencies, covering 17 decades of the electromagnetic spectrum, and variability time-scales from weeks up to a decade. The data were collected from publicly available archives of observatories at radio from Owens Valley Radio Observatory, optical and infrared (B, V, R, I, J, H, and Kbands), X-rays from the Swift and the Rossi X-ray Timing Explorer, high and very high energy (VHE) γ-rays from the Fermi and Very Energetic Radiation Imaging Telescope Array System as well as the High Energy Stereoscopic System. Our results are: (1) the power-law form of the variability power spectra at radio, infrared, and optical frequencies have slopes ∼1.8, indicative of random-walk-type noise processes; (2) the power-law form of the variability power spectra at higher frequencies, from X-rays to VHE  γ-rays, however, have slopes ∼1.2, suggesting a flicker noise-type process; and (3) there is significantly more variability power at X-rays, high and VHE γ-rays on time-scales ≲ 100 d, as compared to lower energies. Our results do not easily fit into a simple model, in which a single compact emission zone is dominating the radiative output of the blazars across all the time-scales probed in our analysis. Instead, we argue that the frequency-dependent shape of the variability power spectra points out a more complex picture, with highly inhomogeneous outflow producing non-thermal emission over an extended, stratified volume.
Mid-Term to Long-Term Outcomes After Total Cervical Disk Arthroplasty Compared With Anterior Diskectomy and Fusion
Authors: Byvaltsev Vadim A. , Stepanov Ivan A. , Riew Daniel K.
Published: April 2020

Study Design:

This study was a meta-analysis of published randomized controlled trials (RCTs).

Objective:

We investigated the mid-term to long-term outcomes of cervical disk arthroplasty (CDA) versus anterior cervical diskectomy and fusion (ACDF) for the surgical treatment of symptomatic cervical disk degenerative disease.

Summary of Background Data:

ACDF has been widely performed for the surgical treatment of symptomatic cervical disk degenerative disease. However, the loss of motion at the operated level has been hypothesized to accelerate adjacent-level disk degeneration. CDA was designed to preserve motion segments and decrease the risk/rate of adjacent segment degeneration. However, it is still uncertain whether mid-term to long-term outcomes after CDA is more effective and safer than those observed after ACDF.

Methods:

Two independent reviewers conducted a search of PubMed, Embase, and the Cochrane Library databases for RCTs with a minimum of 48 months of follow-up. For dichotomous variables, the risk ratio and 95% confidence intervals were calculated. For continuous variables, the standardized mean difference and 95% confidence intervals were calculated.

Results:

Eleven RCTs, finally, were included. The rate of neurological success in the CDA group was not significantly different from that in the ACDF group. The pooled results show that patients who underwent CDA had a significantly greater improvement in Neck Disability Index (NDI) and Short Form 36 Health Survey physical component (SF-36 HSPC) than did those who underwent ACDF. No significant difference was found when comparing the neck and arm pain scores between the CDA and ACDF groups. The overall rate of secondary surgical procedures was significantly lower in patients who underwent CDA than in those who underwent ACDF. We observed similar overall rates of adverse events and adjacent segment degeneration when comparing the CDA group with the ACDF group.

Conclusions:

This meta-analysis provides evidence suggesting that CDA was superior to ACDF in terms of NDI score, SF-36 HSPC score, and low rate of secondary surgical procedures. Furthermore, no significant differences existed between the CDA group and the ACDF group in the neck pain visual analog scale score, arm pain visual analog scale score, the rate of neurological success, adjacent segment degeneration, and adverse events.

Level of Evidence:

Level 1.
Amplified itch: a proposed phenomenon adopted from pain medicine
Authors: Fleischer Alan B.
Published: April 2020

Pain and itch are both similar sensory modalities through which we interact with the environment. Amplified pain is characterized by pain that is out of proportion to the history and physical findings. Amplified pain recognizes that some patients with chronic pain undergo signal amplification. I postulate the existence of amplified itch, in which the experience and the expectation of itch exacerbates itch. These patients should be more treatment-refractory and may not achieve complete itch control. Condition awareness could improve the care of these patients by helping us to consider alternative treatment. Analogous to amplified itch treatment, itch acceptance, and other psychotherapeutic interventions may prove to be valuable approaches.