bluuebunny/crossref_metadata_2025 huggingface dataset:
Progress in the Synthesis of Heterocyclic Compounds Catalyzed by Lipases
Authors: Ma Xiao-Long , Wang Yu-Han , Shen Jin-Hua , Hu Yi
Published: October 2021

Heterocyclic compounds are representative of a larger class of organic compounds, and worthy of attention for many reasons, chief of which is the participation of heterocyclic scaffolds in the skeleton structure of many drugs. Lipases are enzymes with catalytic versatility, and play a key role in catalyzing the reaction of carbon–carbon bond formation, allowing the production of different compounds. This article reviewed the lipase-catalyzed aldol reaction, Knoevenagel reaction, Michael reaction, Mannich reaction, etc., in the synthesis of several classes of heterocyclic compounds with important physiological and pharmacological activities, and also prospected the research focus in lipase-catalyzed chemistry transformations in the future.
Enhanced Efficacy and Reduced Hepatotoxicity by Combination of Gnaphalium affine Extract and Benzbromarone in the Treatment of Rats with Hyperuricemic Nephropathy
Authors: Liu Fei , Liu Xi-Zi , Yang Qian , Han Shi-Yi , Fan Si-Yang
Published: October 2021

Simultaneous oral intake of herbal medicine with chemical drugs may result in beneficial pharmacodynamic efficacy, including additive and synergistic effects with reduced toxicity. Gnaphalium affine D. Don (GAD) is a traditional Chinese Medicine that has been used for the management of hyperuricemia and gout. Benzbromarone (BBR) is one of the first-line drugs used for urate-lowering therapy in China but is toxic to the liver. The present study aimed to determine the effects of GAD and BBR, both alone and in co-treatment (with dosing interval of 1 hour), on chronic hyperuricemic nephropathy (HN) and hepatotoxicity in rats. Our data indicated that GAD significantly inhibited the elevation of serum uric acid, blood urea nitrogen, and creatinine levels in chronic HN rats at doses of 450 and 900 mg/kg/day. The rise in serum alanine aminotransferase and aspartate aminotransferase in BBR (or vehicle)-treated HN rats was significantly reduced by pre- (or post)-administration of GAD (450 mg/kg/day). The q-value >1.15 (by Jin method) indicated synergistic effects of co-treatments of BBR (50 mg/kg) with GAD (450 mg/kg). The synergistic beneficial effects were validated by comparison of BBR alone at a dose of clinical usage (4.5 mg/kg/day, in two divided doses) and BBR + GAD at half dose plus half dose (2.25 + 225 mg/kg/day) or half dose plus full dose (2.25 + 450 mg/kg/day). In conclusion, co-treatment with GAD and BBR holds promise for the management of hyperuricemia and gout.
Spatio-temporal characterization of ultrashort vector
pulses
Authors: Zdagkas Apostolos , Nalla Venkatram , Papasimakis Nikitas , Zheludev Nikolay I.
Published: October 2021

Ultrafast vectorially polarized pulses have found many applications in information and energy transfer owing mainly to the presence of strong longitudinal components and their space-polarization non-separability. Due to their broad spectra, such pulses often exhibit space–time couplings, which significantly affect the pulse propagation dynamics. Although such couplings usually result in reduced energy density at the focal spot, they have been utilized to demonstrate pulse shaping as in the case of a rotating or sliding wavefront as the pulse travels through its focal point. Here, we present a new method for the spatiotemporal characterization of ultrashort cylindrical vector pulses based on a combination of spatially resolved Fourier transform spectroscopy and Mach–Zehnder interferometry. The method provides access to spatially resolved spectral amplitudes and phases of all polarization components of the pulse. We demonstrate the capabilities of the method by completely characterizing a 10 fs radially polarized pulse from a Ti:sapphire laser centered at 800 nm.
Theory of frequency-selective homonuclear dipolar recoupling in solid-state NMR
Authors: Xiao Hang , Zhang Zhengfeng , Yang Jun
Published: October 2021

In solid-state nuclear magnetic resonance, frequency-selective homonuclear dipolar recoupling is key to quantitative distance measurement or selective enhancement of correlations between atoms of interest in multiple-spin systems, which are not amenable to band-selective or broadband recoupling. Previous frequency-selective recoupling is mostly based on the so-called rotational resonance (R2) condition that restricts the application to spin pairs with resonance frequencies differing in integral multiples of the magic-angle spinning (MAS) frequency. Recently, we have proposed a series of frequency-selective homonuclear recoupling sequences called SPR (short for Selective Phase-optimized Recoupling), which have been successfully applied for selective 1H–1H or 13C–13C recoupling under from moderate (∼10 kHz) to ultra-fast (150 kHz) MAS frequencies. In this study, we fully analyze the average Hamiltonian theory of SPR sequences and reveal the origin of frequency selectivity in recoupling. The theoretical description, as well as numerical simulations and experiments, demonstrates that the frequency selectivity can be easily controlled by the flip angle (p) in the (p)ϕk(p)ϕk+π unit in the pSPR-Nn sequences. Small flip angles lead to frequency-selective recoupling, while large flip angles may lead to broadband recoupling in principle. The result shall shed new light on the design of homonuclear recoupling sequences with arbitrary frequency bandwidths.
Photodissociation dynamics of methyl vinyl ketone oxide: A four-carbon unsaturated Criegee intermediate from isoprene ozonolysis
Authors: Wang Guanghan , Liu Tianlin , Caracciolo Adriana , Vansco Michael F. , Trongsiriwat Nisalak , Walsh Patrick J. , Marchetti Barbara , Karsili Tolga N. V. , Lester Marsha I.
Published: October 2021

The electronic spectrum of methyl vinyl ketone oxide (MVK-oxide), a four-carbon Criegee intermediate derived from isoprene ozonolysis, is examined on its second π* ← π transition, involving primarily the vinyl group, at UV wavelengths (λ) below 300 nm. A broad and unstructured spectrum is obtained by a UV-induced ground state depletion method with photoionization detection on the parent mass (m/z 86). Electronic excitation of MVK-oxide results in dissociation to O (1D) products that are characterized using velocity map imaging. Electronic excitation of MVK-oxide on the first π* ← π transition associated primarily with the carbonyl oxide group at λ > 300 nm results in a prompt dissociation and yields broad total kinetic energy release (TKER) and anisotropic angular distributions for the O (1D) + methyl vinyl ketone products. By contrast, electronic excitation at λ ≤ 300 nm results in bimodal TKER and angular distributions, indicating two distinct dissociation pathways to O (1D) products. One pathway is analogous to that at λ > 300 nm, while the second pathway results in very low TKER and isotropic angular distributions indicative of internal conversion to the ground electronic state and statistical unimolecular dissociation.
A comparison of Nellore and Nellore-cross entire male cattle finished in a feedlot in a tropical area of Brazil with respect to carcass characteristics and meat quality after ageing either with or without 60 days of prior frozen storage
Authors: Dias do Nascimento Júlia , Vinicius Morais de Oliveira Marcus , de Nadai Bonin Marina , Ricartes de Oliveira de Oliveira Pollyanna , Vinhas Ítavo Luis Carlos , Ferraz André Luiz Julien , Ferreira Cancio Priscila , Pereira Ávalo Stanley , Surita Lucy Mery Antonia , Miyaki Samara , Motta Couto Allan , Vilalba Rohod Rosileide , Mendes de Oliveira Dalton
Published: October 2021

Context The use of crosses between Bos taurus and Bos indicus has boosted cattle production in tropical areas of Brazil, improving carcass and meat standards. However, there is little information on Canchim animals crossed with Nellore. Additionally, freezing is a preservation method frequently used by consumers, which allows meat to be preserved for a prolonged period, but little is known regarding this effect in meat frozen for 60 days from crossbred animals. Aims The present study sought to evaluate the carcass performance and characteristics, and the effects of freezing prior to ageing on the meat of animals from different genetic groups finished in a feedlot. Methods A total of 26 male cattle were used, consisting of Angus × Nellore (AAN), Canchim × Nellore (CAN) and Nellore (NEL), finished in feedlot. The carcasses were evaluated after slaughter. The steaks (Longissimus thoracis) were submitted to freezing for 0, 30 and 60 days before ageing, and were then aged for 1, 7 and 14 days. Key results Consumption and performance was greater for AAN and CAN animals. The AAN and CAN crossbred cattle presented higher final liveweight, hot carcass weight, dressing-out percentage and rib eye area. Freezing did not affect the meat luminosity, and it reduced the shear force and the purge at 14 days of ageing when frozen for 30 and 60 days. Conclusions The crossbreed between Canchim × Nellore animals is an alternative for termination in a feedlot. Meats frozen before ageing were more tender. Implications Crossbred animals have better carcass performance and characteristics and the pre-freezing process yielded more tender meat. The Canchim is an alternative for crossing with pure Bos indicus animals.
Impact of a prolonged decline in rainfall on eucalypt woodlands in southwestern Australia and its consequences for avifauna
Authors: Angel A. Sara , Bradley J. Stuart
Published: October 2021

Aims Our objective was to establish a relationship between long-term variation in the climatic environment, tree canopy decline and observed effects on the population dynamics of avifauna in the Dryandra Woodlands in southwestern Australia. These geographically isolated remnant woodlands are rich in endemic species and sustain a diverse range of ecological communities, but are threatened by habitat degradation and a decline in rainfall. Methods We used annual rainfall data, averaged from a series of weather stations within 100 km of the Dryandra Woodlands and a time series analysis to investigate long-term changes in annual rainfall. Satellite spectral observations of eight study sites at Dryandra was used to measure changes in Projected Foliage Cover (PFC) of old growth Eucalyptus wandoo at all sites. Our mist-net trapping study across three years and all eight sites, targeted two focal species; the rufous treecreeper (Climacteris rufa) and yellow-plumed honeyeater (Ptilotula ornata). We investigated the relationship between the captures of each species and variation in PFC, between sites and across years. Also in a separate demographic study, capture-mark-recapture data was used to estimate the apparent survival rate of each species, following the robust design for open and closed populations. Key results We demonstrate a long-term and continuing decline in average annual rainfall that is accelerating. We found the rainfall trend is concomitant with a long-term decline in PFC of E. wandoo and that the previous year’s annual rainfall is a predictor of average PFC across all sites. Additionally, we discovered that the PFC at each site, in each year, is a predictor of the number of yellow-plumed honeyeaters which prefer feeding on canopy insects and not a predictor of the predominantly ground-foraging rufous treecreeper. We also found a substantial difference in the apparent survival rates between the two species, with the apparent survival of yellow-plumed honeyeaters being approximately half that of rufous treecreepers. This difference was partially attributed to the likely movement outside of the study area due to decreasing habitat quality. Conclusions and implications Overall, our results do suggest that some impacts of long-term rainfall trends can be traced to particular species through PFC variation, but the response between species to habitat change will differ and depend on species-specific habitat requirements. As increasing greenhouse emissions are associated with declining rainfall in southwestern Australia, this study shows if rainfall decline and habitat degradation continue, it will have catastrophic consequences for woodland ecosystems.
Pannexin-1 and CaV1.1 show reciprocal interaction during excitation–contraction and excitation–transcription coupling in skeletal muscle
Authors: Jaque-Fernández Francisco , Jorquera Gonzalo , Troc-Gajardo Jennifer , Pietri-Rouxel France , Gentil Christel , Buvinic Sonja , Allard Bruno , Jaimovich Enrique , Jacquemond Vincent , Casas Mariana
Published: October 2021

One of the most important functions of skeletal muscle is to respond to nerve stimuli by contracting. This function ensures body movement but also participates in other important physiological roles, like regulation of glucose homeostasis. Muscle activity is closely regulated to adapt to different demands and shows a plasticity that relies on both transcriptional activity and nerve stimuli. These two processes, both dependent on depolarization of the plasma membrane, have so far been regarded as separated and independent processes due to a lack of evidence of common protein partners or molecular mechanisms. In this study, we reveal intimate functional interactions between the process of excitation-induced contraction and the process of excitation-induced transcriptional activity in skeletal muscle. We show that the plasma membrane voltage-sensing protein CaV1.1 and the ATP-releasing channel Pannexin-1 (Panx1) regulate each other in a reciprocal manner, playing roles in both processes. Specifically, knockdown of CaV1.1 produces chronically elevated extracellular ATP concentrations at rest, consistent with disruption of the normal control of Panx1 activity. Conversely, knockdown of Panx1 affects not only activation of transcription but also CaV1.1 function on the control of muscle fiber contraction. Altogether, our results establish the presence of bidirectional functional regulations between the molecular machineries involved in the control of contraction and transcription induced by membrane depolarization of adult muscle fibers. Our results are important for an integrative understanding of skeletal muscle function and may impact our understanding of several neuromuscular diseases.
A review of perfect absorbers based on the two dimensional materials in the visible and near-infrared regimes
Authors: Luo Xin , Zhou Yuanguo , Cai Yijun , Cheng Ziqiang , Liu Zhimin , Wan Wenqiang
Published: October 2021

Two-dimensional (2D) materials, due to their unique electronic, optical and structural properties, have attracted extensive attention of researchers in the world. However, most of 2D materials have low optical absorption efficiencies in the visible and near-infrared regimes, which leads to the weak light–matter interaction and limits their further applications in optoelectronic devices. Thus, enhancing the light–matter interaction of various 2D materials in the visible and near-infrared regimes, has been a key topic for many optoelectronic equipment and related applications. In this topical review, we summarized the recent developments of the 2D materials-based optical absorbers in the visible and near infrared regimes, focusing mainly on the methods and relevant physical mechanisms of several typical perfect absorbers, such as narrowband perfect absorbers, dual-band perfect absorbers, and broadband perfect absorbers. Finally, several prospective research directions from our perspectives are presented at the end.
Status and prospects of Ohmic contacts on two-dimensional semiconductors
Authors: Ni Junhao , Fu Quangui , Ostrikov Kostya (Ken) , Gu Xiaofeng , Nan Haiyan , Xiao Shaoqing
Published: October 2021

In recent years, two-dimensional materials have received more and more attention in the development of semiconductor devices, and their practical applications in optoelectronic devices have also developed rapidly. However, there are still some factors that limit the performance of two-dimensional semiconductor material devices, and one of the most important is Ohmic contact. Here, we elaborate on a variety of approaches to achieve Ohmic contacts on two-dimensional materials and reveal their physical mechanisms. For the work function mismatch problem, we summarize the comparison of barrier heights between different metals and 2D semiconductors. We also examine different methods to solve the problem of Fermi level pinning. For the novel 2D metal-semiconductor contact methods, we analyse their effects on reducing contact resistance from two different perspectives: homojunction and heterojunction. Finally, the challenges of 2D semiconductors in achieving Ohmic contacts are outlined.
Functionalization of mesoporous silica as an effective composite carrier for essential oils with improved sustained release behavior and long-term antibacterial performance
Authors: Zhong Ximing , Gao Fan , Wei Hongjie , Zhou Hongjun , Zhou Xinhua
Published: October 2021

In this work, a novel composite carrier system for loading essential oils was developed by using tetraethyl orthosilicate (TEOS) and (3-aminopropyl) triethoxysilane (APTES) as silica precursors and cetyl trimethyl ammonium bromide (CTAB) as a template, and the resultant aminated mesoporous silica was further chemically modified by polyacrylic acid (PAA). The obtained composite carriers exhibited a high loading capability toward tea tree oil (TTO), and they also significantly improved the release behavior of TTO due to the steric hindrance of silica mesopore and the polymer restriction. Besides, it was found that the release behavior followed the First-Order kinetic model, revealing that the release of TTO was driven by the concentration gradient. In addition, these composite carriers with essential oil-loaded demonstrated remarkable antibacterial performance against E. coli and S. aureus, and they could retain antibacterial performance even after 50 d. Moreover, the antibacterial mechanism was also elucidated with the assistance of nucleic acid and conductivity measurements. Therefore, this work provides a facile and environmentally friendly approach to preparing effective composite carriers for improving the sustained release of essential oils, and the long-term antibacterial performance of these essential oil-loaded composite carriers makes them tremendously potential for practical applications.
A current collect-free Li1.2Ni0.13Co0.13Mn0.54O2 flexible film for high-performance lithium-ion batteries
Authors: Ye Huizi , Cao Kai , Wu Xiaoqin , Zou Tong , Chai Lili , Zhao Yong , Hu Zhengguang , Wang Li
Published: October 2021

Due to the high demand for more convenient flexible devices, there are more requirements for higher performance of flexible batteries. The layered lithium-rich manganese-based Li1.2Ni0.13Co0.13Mn0.54O2 cathode material has the advantages of higher energy density, higher discharge capacity and environmentally friendly, so it can be used for high-performance flexible electrode cathode material. Its theoretical capacity can reach more than 250 mAh g−1, which is higher than most cathode materials currently used in commercialization. Here we synthesize Li1.2Ni0.13Co0.13Mn0.54O2 (LNCM) cathode, and then use a simple method to make a current collect-free LNCM flexible film. This film has excellent flexibility and electrochemical performance. At 25 mA g−1, its initial discharge capacity reaches 314.0 mAh g−1. After 200 cycles of 500 mA g−1, its capacity retention rate is 82.1%, the attenuation is about 0.08% per cycle. Moreover, by bending at any position of the flexible film, it can still remain intact, and the soft-packaged battery made by the flexible film can still be used under the bending condition and keep the brightness of the LED lamp unchanged. This shows that using Li1.2Ni0.13Co0.13Mn0.54O2 to make high-performance flexible electrodes is a simple and effective method, which is expected to be practically applied to flexible electronic devices.
An 8 channel parallel transmit system with current sensor feedback for MRI-guided interventional applications
Authors: Godinez Felipe , Tomi-Tricot Raphael , Quesson Bruno , Barthel Matthias , Lykowsky Gunthard , Scott Greig , Razavi Reza , Hajnal Joseph , Malik Shaihan
Published: October 2021

Background. Parallel transmit (pTx) has introduced many benefits to magnetic resonance imaging (MRI) with regard to decreased specific absorption rates and improved transmit field homogeneity, of particular importance in applications at higher magnetic field strengths. PTx has also been proposed as a solution to mitigating dangerous RF induced heating of elongated conductive devices such as those used in cardiac interventions. In this work we present a system that can augment a conventional scanner with pTx, in particular for use in interventional MRI for guidewire safety, by adjusting the amplitude and phase of each channel right before the start of the imaging pulses. Methods. The pTx system was designed to work in-line with a 1.5 T MRI while the RF synthesis and imaging control was maintained on the host MR scanner. The add-on pTx system relies on the RF transmit signal, unblanking pulse, and a protocol driven trigger from the scanner. The RF transmit was split into multiple fully modulated transmit signals to drive an array of custom transceiver coils. The performance of the 8-channel implementation was tested with regards to active and real-time control of RF induced currents on a standard guidewire, heating mitigation tests, and anatomical imaging in sheep. Results. The pTx system was intended to update RF shims in real-time and it was demonstrated that the safe RF shim could be determined while the guidewire is moved. The anatomical imaging demonstrated that cardiac anatomy and neighbouring superficial structures could be fully characterized with the pTx system inline. Conclusion. We have presented the design and performance of a real-time feedback control pTx system capable of adding such capabilities to a conventional MRI with the focus of guidewire imaging in cardiac interventional MRI applications.
Automatic cough classification for tuberculosis screening in a real-world environment
Authors: Pahar Madhurananda , Klopper Marisa , Reeve Byron , Warren Rob , Theron Grant , Niesler Thomas
Published: October 2021

Objective. The automatic discrimination between the coughing sounds produced by patients with tuberculosis (TB) and those produced by patients with other lung ailments. Approach. We present experiments based on a dataset of 1358 forced cough recordings obtained in a developing-world clinic from 16 patients with confirmed active pulmonary TB and 35 patients suffering from respiratory conditions suggestive of TB but confirmed to be TB negative. Using nested cross-validation, we have trained and evaluated five machine learning classifiers: logistic regression (LR), support vector machines, k-nearest neighbour, multilayer perceptrons and convolutional neural networks. Main Results. Although classification is possible in all cases, the best performance is achieved using LR. In combination with feature selection by sequential forward selection, our best LR system achieves an area under the ROC curve (AUC) of 0.94 using 23 features selected from a set of 78 high-resolution mel-frequency cepstral coefficients. This system achieves a sensitivity of 93% at a specificity of 95% and thus exceeds the 90% sensitivity at 70% specificity specification considered by the World Health Organisation (WHO) as a minimal requirement for a community-based TB triage test. Significance. The automatic classification of cough audio sounds, when applied to symptomatic patients requiring investigation for TB, can meet the WHO triage specifications for the identification of patients who should undergo expensive molecular downstream testing. This makes it a promising and viable means of low cost, easily deployable frontline screening for TB, which can benefit especially developing countries with a heavy TB burden.
Measurements of atoms and metastable species in N2 and H2–N2 nanosecond pulse plasmas
Authors: Yang Xin , Jans Elijah , Richards Caleb , Raskar Sai , van den Bekerom Dirk , Wu Kai , Adamovich Igor V
Published: October 2021

Time-resolved, absolute number densities of metastable N2(A3Σ
u

+, v = 0, 1) molecules, ground state N2 and H atoms, and rotational–translational temperature have been measured by tunable diode laser absorption spectroscopy and two-photon absorption laser-induced fluorescence in diffuse N2 and N2–H2 plasmas during and after a nanosecond pulse discharge burst. Comparison of the measurement results with the kinetic modeling predictions, specifically the significant reduction of the N2(A3Σ
u

+) populations and the rate of N atom generation during the burst, suggests that these two trends are related. The slow N atom decay in the afterglow, on a time scale longer than the discharge burst, demonstrates that the latter trend is not affected by N atom recombination, diffusion to the walls, or convection with the flow. This leads to the conclusion that the energy pooling in collisions of N2(A3Σ
u

+) molecules is a major channel of N2 dissociation in electric discharges where a significant fraction of the input energy goes to electronic excitation of N2. Additional measurements in a 1% H2–N2 mixture demonstrate a further significant reduction of N2(A3Σ
u

+, v = 0, 1) populations, due to the rapid quenching by H atoms accumulating in the plasma. Comparison with the modeling predictions suggests that the N2(A3Σ
u

+) molecules may be initially formed in the highly vibrationally excited states. The reduction of the N2(A3Σ
u

+) number density also diminishes the contribution of the energy pooling process into N2 dissociation, thus reducing the N atom number density. The rate of N atom generation during the burst also decreases, due to its strong coupling to N2(A3Σ
u

+, v) populations. On the other hand, the rate of H atom generation, produced predominantly by the dissociative quenching of the excited electronic states of N2 by H2, remains about the same during the burst, resulting in a nearly linear rise in the H atom number density. Comparison of the kinetic model predictions with the experimental results suggests that the yield of H atoms during the quenching of the excited electronic state of N2 by molecular H2 is significantly less than 100%. The present results quantify the yield of N and H atoms in high-pressure H2–N2 plasmas, which have significant potential for ammonia generation using plasma-assisted catalysis.
Systematic study on photoexcited carrier dynamics related to defects in GeSn films with low Sn content at room temperature
Authors: Son Bongkwon , Zhang Lin , Jung Yongduck , Zhou Hao , Nam Donguk , Tan Chuan Seng
Published: October 2021

Germanium–tin (GeSn) alloys have received much attention thanks to their optical/electrical properties and their operation in the mid-infrared range. However, dislocations/defects in GeSn films serve as trap states, limiting radiative recombination/generation via band-edges. In this work, the impact of the trap states in GeSn with varying Sn contents is investigated. The systematic study reveals that the defects/dislocations in GeSn contribute to the carrier dynamics, mainly originated from the trap states near GeSn/Ge interface. Through photoluminescence (PL) study, the broad PL peak of the trap state for GeSn exists at ∼0.57 eV. The increase in Sn content mitigates the trap-related carrier dynamics. Besides, the increase in GeSn thickness effectively suppresses the interface-related carrier dynamic. By increasing thickness from 180 to ∼900 nm, the external quantum efficiency is enhanced by ∼10×. This study provides a comprehensive understanding of trap-related carrier dynamics in a GeSn material system at room temperature.
Investigating the exciton formation zone and its roles in phosphorescent organic light emitting diodes
Authors: Liu Wenxing , Cui Rongzhen , Guan Xi , Sun Weidong , Zhou Liang , Qin Dashan
Published: October 2021

The exciton formation zone has been studied in phosphorescent organic light emitting diodes (OLEDs). It is found that the width (W) of the exciton formation zone can be increased by reducing the transit time for holes (electrons) from the anode (cathode) into the emissive layer (EML) by decreasing the thickness of the hole (electron) transport layer. The increase in the thickness of the EML enables the exciton formation zone to be widened. The efficiency roll-off of the device is relieved when W increases. The device stability is found to be directly proportional to the product of W and the thickness of the electron transport layer. A thicker electron transport layer better suppresses diffusion of the metal cathode into the EML, increasing device stability but simultaneously decreasing the transit time for electrons from the cathode into the EML, and thereby W, so decreasing device stability. We also investigated the effect of charge carrier mobilities in the EML, modified by dye concentration, on W. The current research provides novel insights into guiding the delicate designs of OLEDs, hopefully pushing OLED technology towards high-luminance applications.
Device-independent quantum key distribution from computational assumptions
Authors: Metger Tony , Dulek Yfke , Coladangelo Andrea , Arnon-Friedman Rotem
Published: October 2021

In device-independent quantum key distribution (DIQKD), an adversary prepares a device consisting of two components, distributed to Alice and Bob, who use the device to generate a secure key. The security of existing DIQKD schemes holds under the assumption that the two components of the device cannot communicate with one another during the protocol execution. This is called the no-communication assumption in DIQKD. Here, we show how to replace this assumption, which can be hard to enforce in practice, by a standard computational assumption from post-quantum cryptography: we give a protocol that produces secure keys even when the components of an adversarial device can exchange arbitrary quantum communication, assuming the device is computationally bounded. Importantly, the computational assumption only needs to hold during the protocol execution—the keys generated at the end of the protocol are information-theoretically secure as in standard DIQKD protocols.
Gravitational waves from resonant amplification of curvature perturbations during inflation
Authors: Peng Zhi-Zhang , Fu Chengjie , Liu Jing , Guo Zong-Kuan , Cai Rong-Gen
Published: October 2021

Parametric resonance in a single-field inflationary model with a periodic structure on the potential gives rise to curvature perturbations with large amplitudes on small scales, which could result in observable primordial black holes (PBHs) and concomitant gravitational waves (GWs) induced by curvature perturbations in the radiation-dominated era. In such a model, GWs associated with the PBH formation were investigated in ref. [1].
In this paper, we consider a stochastic GW background sourced by inflaton perturbations resonantly amplified during inflation. We compute the energy spectra of induced GWs produced both during inflation and in the radiation-dominated era, and find that the peak of the energy spectrum of the former is much higher than that of the latter, but is located at a lower frequency. Moreover, the energy spectrum of induced GWs produced during inflation exhibits a unique oscillating character in the ultraviolet region. Both the stochastic GW backgrounds are expected to be detected by future space-based laser interferometers.
Signatures of primordial black hole dark matter at DUNE and THEIA
Authors: De Romeri Valentina , Martínez-Miravé Pablo , Tórtola Mariam
Published: October 2021

Primordial black holes (PBHs) are a potential dark matter candidate whose masses can span over many orders of magnitude. If they have masses in the 1015–1017 g range, they can emit sizeable fluxes of MeV neutrinos through evaporation via Hawking radiation. We explore the possibility of detecting light (non-)rotating PBHs with future neutrino experiments. We focus on two next generation facilities: the Deep Underground Neutrino Experiment (DUNE) and THEIA. We simulate the expected event spectra at both experiments assuming different PBH mass distributions and spins, and we extract the expected 95% C.L. sensitivities to these scenarios. Our analysis shows that future neutrino experiments like DUNE and THEIA will be able to set competitive constraints on PBH dark matter, thus providing complementary probes in a part of the PBH parameter space currently constrained mainly by photon data.
Model independent prediction of the spectral index of primordial quantum fluctuations
Authors: Gómez César , Jimenez Raul
Published: October 2021

One of the most important achievements of inflationary cosmology is to predict a departure from scale invariance of the power spectrum for cosmological scalar perturbations. This tilt is understood as a consequence of a quasi de Sitter classical equation of state describing the inflationary dark energy dominated era. Here, following previous work, we find a departure of scale invariance for the quantum Fisher information associated to de Sitter vacuum for scalar quantum spectator modes. This gives rise to a purely quantum cosmological tilt with a well defined dependence on energy scale. This quantum tilt is imprinted, in a scale dependent energy uncertainty for the spectator modes. The effective quasi de Sitter description of this model independent energy uncertainty uniquely sets the effective quasi de Sitter parameters (i.e., the small deviation from the cosmological constant equation of state) at all energy scales. In particular, in the slow-roll regime characterized by an almost constant ϵ, the quantum Fisher — model independent — prediction for the spectral index is n
s = 0.9672. Moreover, the energy scale dependence of the quantum cosmological tilt implies the existence of a cosmological phase transition at energies higher than the CMB scale and of the order of 1 Mpc-1 where the tilt goes from red into blue. This strongly suggest the existence of a pre-inflationary phase where the effective scalaron contributes to the spectral index as normal relativistic matter and where the corresponding growth of the power spectrum can result in dark matter in the form of small mass primordial black holes. The source and features of the quantum cosmological tilt leading to these predictions are determined by the entanglement features of the de Sitter α- vacuum states.
Power exhaust concepts and divertor designs for Japanese and European DEMO fusion reactors
Authors: Asakura N. , Hoshino K. , Kakudate S. , Subba F. , Vorpahl C. , Homma Y. , Utoh H. , Someya Y. , Sakamoto Y. , Hiwatari R. , Suzuki S. , You J.-H. , Siccinio M. , Federici G.
Published: October 2021

Concepts of the power exhaust and divertor design have been developed, with a high priority in the pre-conceptual design phase of the Japan–Europe broader approach DEMO design activity (BA DDA). Common critical issues are the large power exhaust and its fraction in the main plasma and divertor by the radiative cooling (P
rad
tot/P
heat ⩾ 0.8). Different exhaust concepts in the main plasma and divertor have been developed for Japanese (JA) and European (EU) DEMOs. JA proposed a conventional closed divertor geometry to challenge large P
sep/R
p handling of 30–35 MW m−1 in order to maintain the radiation fraction in the main plasma at the ITER-level (f
rad
main = P
rad
main/P
heat ∼ 0.4) and higher plasma performance. EU challenged both increasing f
rad
main to ∼0.65 and handling the ITER-level P
sep/R
p in the open divertor geometry. Power exhaust simulations have been performed by SONIC (JA) and SOLPS5.1 (EU) with corresponding P
sep = 250–300 MW and 150–200 MW, respectively. Both results showed that large divertor radiation fraction (P
rad
div/P
sep ⩾ 0.8) was required to reduce both peak q
target (⩽10 MW m−2) and T
e,i
div. In addition, the JA divertor performance with EU-reference P
sep of 150 MW showed benefit of the closed geometry to reduce the peak q
target and T
e,i
div near the separatrix, and to produce the partial detachment. Integrated designs of the water cooled divertor target, cassette and coolant pipe routing have been developed in both EU and JA, based on the tungsten (W) monoblock concept with Cu-alloy pipe. For year-long operation, DEMO-specific risks such as radiation embrittlement of Cu-interlayers and Cu-alloy cooling pipe were recognized, and both foresee higher water temperature (130 °C–200 °C) compared to that for ITER. At the same time, several improved technologies of high heat flux components have been developed in EU, and different heat sink design, i.e. Cu-alloy cooling pipes for targets and RAFM steel ones for the baffle, dome and cassette, was proposed in JA. The two approaches provide important case-studies of the DEMO divertor, and will significantly contribute to both DEMO designs.
Numerical study on nonlinear double tearing mode in ITER
Authors: Lu S.S. , Ma Z.W. , Tang W. , Zhang W. , Liu Y.
Published: October 2021

The nonlinear dynamics of the m/n = 2/1 double tearing mode (DTM) in ITER are systematically studied using the three-dimensional toroidal magnetohydrodynamic code, CLT. We carefully investigate the effects of the radial locations and magnetic shear strengths of the inner and outer rational surfaces r
1, r
2, s
1 and s
2, as well as the safety factor at the magnetic axis q
0 on DTM. It is found that the explosive burst takes place only with the moderate separation of the two rational surfaces or the stronger magnetic shear strength in which the strong interaction of magnetic islands in the two rational surfaces happens in the early nonlinear phase of the island development. The explosive burst can result from either the direct mutual driving associated with the fast growth island in the two rational surfaces or a strong nonlinear mode–mode coupling. For a large separation and a weak shear strength of the two rational surfaces, the magnetic islands saturate without strong interaction with each other, and (w
in + w
out)/2 is always below the separation Δr
s. For a small separation, the kinetic evolution of DTM only exhibits an oscillation with a very low level and then decreases.
Projected changes in global terrestrial near-surface wind speed in 1.5 °C–4.0 °C global warming levels
Authors: Zha Jinlin , Shen Cheng , Li Zhibo , Wu Jian , Zhao Deming , Fan Wenxuan , Sun Ming , Azorin-Molina Cesar , Deng Kaiqiang
Published: October 2021

Understanding future changes in global terrestrial near-surface wind speed (NSWS) in specific global warming level (GWL) is crucial for climate change adaption. Previous studies have projected the NSWS changes; however, the changes of NSWS with different GWLs have yet to be studied. In this paper, we employ the Max Planck Institute Earth System Model large ensembles to evaluate the contributions of different GWLs to the NSWS changes. The results show that the NSWS decreases over the Northern Hemisphere (NH) mid-to-high latitudes and increases over the Southern Hemisphere (SH) as the GWL increases by 1.5 °C–4.0 °C relative to the preindustrial period, and that these characteristics are more significant with the stronger GWL. The probability density of the NSWS shifts toward weak winds over NH and strong winds over SH between the current climate and the 4.0 °C GWL. Compared to 1.5 °C GWL, the NSWS decreases −0.066 m s−1 over NH and increases +0.065 m s−1 over SH with 4.0 °C GWL, especially for East Asia and South America, the decrease and increase are most significant, which reach −0.21 and +0.093 m s−1, respectively. Changes in the temperature gradient induced by global warming could be the primary factor causing the interhemispheric asymmetry of future NSWS changes. Intensified global warming induces the reduction in Hadley, Ferrell, and Polar cells over NH and the strengthening of the Hadley cell over SH could be another determinant of asymmetry changes in NSWS between two hemispheres.
Species-specific herbivore grazing of type-specific grassland can assist with promotion of shallow layer of soil carbon sequestration
Authors: Li Jie , Chai Hua , Ding Shiwen , Wang Jinsong , Li Xincheng , Li Yinong , Li Tianyun , Liu Jushan , Wang Hongjun , Liang Cunzhu , Wang Chengjie , Liu Yuan , Luo Yiqi , Wang Ling , Wang Deli
Published: October 2021

Grassland soils represent a significant potential pool for the sequestering of atmospheric CO2; however, the magnitude of this pool depends to a certain extent on the grazing management of the grassland. Whether different herbivore species and combinations (herbivore assemblage) influence the soil organic carbon (SOC) in various grasslands remains unclear. Here we have investigated the impacts of herbivore assemblages (NG, no grazing; SG, sheep grazing; CG, cattle grazing; and MG, mixed grazing of sheep and cattle) under moderate grazing intensity on a shallow layer of SOC storage across the three different grassland types (meadow steppe, typical steppe, and desert steppe) in the temperate steppes of Eastern Eurasia. We found that herbivore-species-specific effects on SOC storage depended on the grassland type. In mesic grasslands (i.e. meadow steppe and typical steppe), CG enhanced SOC storage, but there were no effects from SG. In contrast, SG in the xeric grassland (i.e. desert steppe) dramatically increased SOC storage while no effects were observed for CG. Importantly, MG of sheep and cattle consistently increased SOC storage across all grassland types. We suggest that adopting herbivore-type-specific stewardship in different grasslands could assist with the enhancement of ecosystem C functionality and services; large herbivores and small herbivores are suitable for grazing in mesic grasslands and xeric grasslands, respectively. Moreover, MG with diverse herbivores may be the optimal moderate grazing mode for soil C sequestration in most grasslands of northern China.
Anhedonic Depression Is Not Associated With Risk of Recurrent Major Adverse Cardiac Events and All-Cause Mortality in Acute Coronary Syndrome Patients
Authors: Sanchez Gabriel J , Sumner Jennifer A , Schwartz Joseph E , Burg Matthew M , Ye Siqin , Whang William , Peacock James , Duer-Hefele Joan , Clemow Lynn , Kronish Ian M , Davidson Karina W
Published: October 2021

Background

Depression after acute coronary syndrome (ACS) is common and increases risks of adverse outcomes, but it remains unclear which depression features are most associated with major adverse cardiac events (MACE) and all-cause mortality (ACM).

Purpose

To examine whether a subtype of depression characterized by anhedonia and major depressive disorder (MDD) predicts 1-year MACE/ACM occurrence in ACS patients compared to no MDD history. We also consider other depression features in the literature as predictors.

Methods

Patients (N = 1,087) presenting to a hospital with ACS completed a self-report measure of current depressive symptoms in-hospital and a diagnostic interview assessing MDD within 1 week post-hospitalization. MACE/ACM events were assessed at 1-, 6-, and 12-month follow-ups. Cox regression models were used to examine the association of the anhedonic depression subtype and MDD without anhedonia with time to MACE/ACM, adjusting for sociodemographic and clinical covariates.

Results

There were 142 MACE/ACM events over the 12-month follow-up. The 1-year MACE/ACM in patients with anhedonic depression, compared to those with no MDD, was somewhat higher in an age-adjusted model (hazard ratio [HR] = 1.63, p = .08), but was not significant after further covariate adjustment (HR = 1.24, p = .47). Of the additional depression features, moderate-to-severe self-reported depressive symptoms significantly predicted the risk of MACE/ACM, even in covariate-adjusted models (HR = 1.72, p = .04), but the continuous measure of self-reported depressive symptoms did not.

Conclusion

The anhedonic depression subtype did not uniquely predict MACE/ACM as hypothesized. Moderate-to-severe levels of total self-reported depressive symptoms, however, may be associated with increased MACE/ACM risk, even after accounting for potential sociodemographic and clinical confounders.
Aortic Root Diameter in Hypertensive Patients With Various Stages of Obstructive Sleep Apnea
Authors: Wang Dian , Xu Jian-Zhong , Kang Yuan-Yuan , Zhang Wei , Hu Lei-Xiao , Wang Ji-Guang
Published: October 2021

BACKGROUND

Obstructive sleep apnea (OSA) is a risk factor of several cardiovascular diseases. We investigated the association between aortic root diameter and hypoxia-related parameters in hypertensive patients with OSA.

METHODS

Our study included 242 hypertensive patients with OSA (52 mild, 71 moderate, and 119 severe). All the patients underwent echocardiography for measuring aortic root diameter and polysomnography for measuring apnea–hypopnea index (AHI), oxygen desaturation index, and time spent with oxygen desaturation less than 90%.

RESULTS

The study patients included 19.8% women and had a mean (±SD) age of 49.9 ± 12.9 years, a mean aortic root diameter of 33.4 ± 2.6 mm, and a prevalence of echocardiographic aortic root dilation of 3.7%. Patients with mild, moderate, and severe OSA had similar echocardiographic left ventricular structure. However, patients with severe OSA had a significantly (P < 0.05) greater aortic root diameter (33.9 ± 2.4 mm vs. 32.4 ± 2.2 and 33.4 ± 2.9 mm, respectively) and higher prevalence of aortic root dilatation (5% vs. 1% and 3%, respectively) than those with mild and moderate OSA. Aortic root diameter corrected by body height was significantly (P < 0.001) associated with AHI, oxygen desaturation index and time spent with oxygen desaturation less than 90% (r = 0.23–0.33). After adjustment for various confounding factors, the associations between aortic root diameter and polysomnography parameters remained statistically significant (P < 0.05).

CONCLUSIONS

The severity of OSA was associated with the aortic root diameter. Patients with severe OSA had a greater aortic root diameter.
Identifying key roles of the pharmacy technician in primary care settings
Authors: Gadd Shannon , Lopez Conrad E , Nelson Cory A , Le Trung Q , Valle-Oseguera Cynthia S , Cox Nicholas , Buu Jenni , Turner Kyle
Published: October 2021

Purpose

As the pharmacist’s role expands, particularly in primary care practice settings, there is an opportunity for expansion of pharmacy technician duties to aid in administrative and clinical tasks that do not require the pharmacist’s professional judgment. Identifying, defining, and expanding the roles of pharmacy technicians has been deemed a key part of the pharmacy practice model. These roles have been shown to enhance pharmacist efficiency and patient outreach; however, examples of the various innovative activities performed by technicians in the primary care setting are lacking in the literature.

Methods

The duties of primary care pharmacy technicians were compiled and defined in 2 different healthcare systems. The role of the technician was separately implemented at each institution, and study designs and protocols were individually created and executed. One institution utilized a 4-round consensus-building process to systematically refine and codify tasks for a dictionary of duties. The second institution utilized a free-text survey, task documentation data in the electronic medical record, and a telephone discussion with the technicians.

Results

Despite a lack of methods- and data-sharing between the 2 institutions, similar tasks were identified, including conducting patient outreach, assisting with medication affordability and access, providing patient education, managing referrals, and scheduling appointments. Differences in technician involvement were noted in areas such as prior authorization, care coordination meetings, and quality improvement projects.

Conclusion

Pharmacy technicians are a helpful, yet underutilized, resource in the primary care setting. Further exploration of technician roles is needed to determine the financial and clinical impact of expanding these roles.