bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ultra-high rate of temperature increment from superparamagnetic nanoparticles for highly efficient hyperthermia
Authors: Lee Jae-Hyeok , Kim Bosung , Kim Yongsub , Kim Sang-Koog 
Published: March 2021

AbstractThe magneto-thermal effect, which represents the conversion of magnetostatic energy to heat from magnetic materials, has been spotlighted for potential therapeutic usage in hyperthermia treatments. However, the realization of its potential has been challenged owing to the limited heating from the magnetic nanoparticles. Here, we explored a new-concept of magneto-thermal modality marked by low-power-driven, fast resonant spin-excitation followed by consequent energy dissipation, which concept has yet to be realized for current hyperthermia applications. We investigated the effect of spin resonance-mediated heat dissipation using superparamagnetic Fe3O4 nanoparticles and achieved an extraordinary initial temperature increment rate of more than 150 K/s, which is a significant increase in comparison to that for the conventional magnetic heat induction of nanoparticles. This work would offer highly efficient heat generation and precision wireless controllability for realization of magnetic-hyperthermia-based medical treatment.
A common optical approach to thickness optimization in polymer and perovskite solar cells
Authors: Iakobson Olga D. , Gribkova Oxana L. , Tameev Alexey R. , Nunzi Jean-Michel 
Published: March 2021

AbstractThe structure of experimentally designed solar cells was optimized in terms of the photoactive layer thickness for both organic bulk heterojunction and hybrid perovskite solar cells. The photoactive layer thickness had a totally different behavior on the performance of the organic and hybrid solar cells. Analysis of the optical parameters using transfer matrix modeling within the Maxwell–Garnett effective refractive index model shows that light absorbance and exciton generation rate in the photoactive layer can be used to optimize the thickness range of the photoactive layer. Complete agreement between experimental and simulated data for solar cells with photoactive materials that have very different natures proves the validity of the proposed modeling method. The proposed simple method which is not time-consuming to implement permits to obtain a preliminary assessment of the reasonable range of layer thickness that will be needed for designing experimental samples.
The impact of pyroclastic density currents duration on humans: the case of the AD 79 eruption of Vesuvius
Authors: Dellino Pierfrancesco , Dioguardi Fabio , Isaia Roberto , Sulpizio Roberto , Mele Daniela 
Published: March 2021

AbstractPyroclastic density currents are ground hugging gas-particle flows that originate from the collapse of an eruption column or lava dome. They move away from the volcano at high speed, causing devastation. The impact is generally associated with flow dynamic pressure and temperature. Little emphasis has yet been given to flow duration, although it is emerging that the survival of people engulfed in a current strongly depends on the exposure time. The AD 79 event of Somma-Vesuvius is used here to demonstrate the impact of pyroclastic density currents on humans during an historical eruption. At Herculaneum, at the foot of the volcano, the temperature and strength of the flow were so high that survival was impossible. At Pompeii, in the distal area, we use a new model indicating that the current had low strength and low temperature, which is confirmed by the absence of signs of trauma on corpses. Under such conditions, survival should have been possible if the current lasted a few minutes or less. Instead, our calculations demonstrate a flow duration of 17 min, long enough to make lethal the breathing of ash suspended in the current. We conclude that in distal areas where the mechanical and thermal effects of a pyroclastic density currents are diminished, flow duration is the key for survival.
Influence of intra and inter species variation in chilies (Capsicum spp.) on metabolite composition of three fruit segments
Authors: Zamljen Tilen , Jakopič Jerneja , Hudina Metka , Veberič Robert , Slatnar Ana 
Published: March 2021

AbstractTwenty-one different cultivars from four different species were examined. The highest dry weight was present in seeds (between 35 and 50%) and the average water content was 60%. Placenta and pericarp contained on average 86% water. Total sugars variation between species was 60%. The most concentrated in the various cultivar pericarps were ascorbic acid ranging from 368.1 to 2105.6 mg/100 g DW and citric acid ranging from 1464.3 to 9479.9 mg/100 g DW. Total phenolic content ranged from 2599.1 mg/100 DW in ‘Chilli AS- Rot’ to 7766.7 mg/100 g DW in 'Carolina Reaper'. The placenta had 23.5 times higher phenolic content than seeds. C. chinense and C. chinense × C. frutescens had 3.5 to 5 times higher capsaicinoid content compared to C. annuum and C. baccatum, with 'Carolina Reaper' having the highest content at 7334.3 mg/100 g DW and 'Chilli AS- Rot' the lowest (318.7 mg/100 g DW).
Oleoresins and naturally occurring compounds of Copaifera genus as antibacterial and antivirulence agents against periodontal pathogens
Authors: Abrão Fariza , Silva Thayná Souza , Moura Claudia L. , Ambrósio Sérgio Ricardo , Veneziani Rodrigo Cassio Sola , de Paiva Raphael E. F. , Bastos Jairo Kenupp , Martins Carlos Henrique Gomes 
Published: March 2021

AbstractInvasion of periodontal tissues byPorphyromonas gingivalisandAggregatibacter actinomycetemcomitanscan be associated with aggressive forms of periodontitis. Oleoresins from different copaifera species and their compounds display various pharmacological properties. The present study evaluates the antibacterial and antivirulence activity of oleoresins obtained from different copaifera species and of ten isolated compounds against two causative agents of periodontitis. The following assays were performed: determination of the minimum inhibitory concentration (MIC), determination of the minimum bactericidal concentration (MBC), and determination of the antibiofilm activity by inhibition of biofilm formation and biofilm eradication tests. The antivirulence activity was assessed by hemagglutination,P. gingivalisArg-X and Lis-X cysteine protease inhibition assay, andA. actinomycetemcomitansleukotoxin inhibition assay. The MIC and MBC of the oleoresins and isolated compounds1,2, and3ranged from 1.59 to 50 μg/mL againstP. gingivalis(ATCC 33277) and clinical isolates and from 6.25 to 400 μg/mL againstA. actinomycetemcomitans(ATCC 43717) and clinical isolates. About the antibiofilm activity, the oleoresins and isolated compounds1,2, and3inhibited biofilm formation by at least 50% and eradicated pre-formedP. gingivalisandA. actinomycetemcomitansbiofilms in the monospecies and multispecies modes. A promising activity concerning cysteine protease and leucotoxin inhibition was also evident. In addition, molecular docking analysis was performed. The investigated oleoresins and their compounds may play an important role in the search for novel sources of agents that can act against periodontal pathogens.
Dissociable electrophysiological measures of natural language processing reveal differences in speech comprehension strategy in healthy ageing
Authors: Broderick Michael P. , Di Liberto Giovanni M. , Anderson Andrew J. , Rofes Adrià , Lalor Edmund C. 
Published: March 2021

AbstractHealthy ageing leads to changes in the brain that impact upon sensory and cognitive processing. It is not fully clear how these changes affect the processing of everyday spoken language. Prediction is thought to play an important role in language comprehension, where information about upcoming words is pre-activated across multiple representational levels. However, evidence from electrophysiology suggests differences in how older and younger adults use context-based predictions, particularly at the level of semantic representation. We investigate these differences during natural speech comprehension by presenting older and younger subjects with continuous, narrative speech while recording their electroencephalogram. We use time-lagged linear regression to test how distinct computational measures of (1) semantic dissimilarity and (2) lexical surprisal are processed in the brains of both groups. Our results reveal dissociable neural correlates of these two measures that suggest differences in how younger and older adults successfully comprehend speech. Specifically, our results suggest that, while younger and older subjects both employ context-based lexical predictions, older subjects are significantly less likely to pre-activate the semantic features relating to upcoming words. Furthermore, across our group of older adults, we show that the weaker the neural signature of this semantic pre-activation mechanism, the lower a subject’s semantic verbal fluency score. We interpret these findings as prediction playing a generally reduced role at a semantic level in the brains of older listeners during speech comprehension and that these changes may be part of an overall strategy to successfully comprehend speech with reduced cognitive resources.
Prognostic value of cardiac biomarkers in COVID-19 infection
Authors: Sheth Aakash , Modi Malak , Dawson Desiree’ , Dominic Paari 
Published: March 2021

AbstractMultiple Biomarkers have recently been shown to be elevated in COVID-19, a respiratory infection with multi-organ dysfunction; however, information regarding the prognostic value of cardiac biomarkers as it relates to disease severity and cardiac injury are inconsistent. The goal of this meta-analysis was to summarize the evidence regarding the prognostic relevance of cardiac biomarkers from data available in published reports. PubMed, Embase and Web of Science were searched from inception through April 2020 for studies comparing median values of cardiac biomarkers in critically ill versus non-critically ill COVID-19 patients, or patients who died versus those who survived. The weighted mean differences (WMD) and 95% confidence interval (CI) between the groups were calculated for each study and combined using a random effects meta-analysis model. The odds ratio (OR) for mortality based on cardiac injury was combined from studies reporting it. Troponin levels were significantly higher in COVID-19 patients who died or were critically ill versus those who were alive or not critically ill (WMD 0.57, 95% CI 0.43–0.70, p < 0.001). Additionally, BNP levels were also significantly higher in patients who died or were critically ill (WMD 0.45, 95% CI − 0.21–0.69, p < 0.001). Cardiac injury was independently associated with significantly increased odds of mortality (OR 6.641, 95% CI 1.26–35.1, p = 0.03). A significant difference in levels of D-dimer was seen in those who died or were critically ill. CK levels were only significantly higher in those who died versus those who were alive (WMD 0.79, 95% CI 0.25–1.33, p = 0.004). Cardiac biomarkers add prognostic value to the determination of the severity of COVID-19 and can predict mortality.
Commentary on: Renin–angiotensin system overactivation in perivascular adipose tissue contributes to vascular dysfunction in heart failure
Authors: Ferrario Carlos M. 
Published: March 2021

Abstract
We comment on the publication of a paper in which Brazilian investigators evaluate the anticontractile response of perivascular adipose tissue (PVAT) in experimental heart failure (HF) induced in rats by occlusion of a coronary artery.
Diagnostik und Differenzialdiagnosen der nicht traumatischen Subarachnoidalblutung
Authors: Schulte-Altedorneburg Gernot 
Published: March 2021

ZusammenfassungDie nicht traumatische Subarachnoidalblutung (SAB) ist meist auf die Ruptur eines intrakraniellen Aneurysmas zurückzuführen. Aber es gibt weitere, sehr unterschiedliche Erkrankungen, die mögliche Differenzialdiagnosen sind. Sie richtig zu diagnostizieren, ist alleine schon von Relevanz, weil sich Ätiologie, Behandlung, Komplikationen, Prognose und sogar die Folgebildgebung unterscheiden.
Brave New Psychiatry? Oder: Wohin führt die Künstliche Intelligenz die Psychiatrie?
Authors: Leidinger Friedrich 
Published: March 2021

ZusammenfassungEin kritischer Überblick über Publikationen zur Anwendung von „lernenden Algorithmen“ und „künstlichen neuronalen Netzen“ in der Psychiatrie führt in ein dystopisches Zukunftszenario. Dem Ansatz einer Nosologie auf molekularbiologischer Basis wird ein aus der kritischen Auseinandersetzung mit der Geschichte und im Dialog mit den Betroffenen entwickeltes ökologisches Störungskonzept der Psychiatrie gegenübergestellt.
Mode control by rearrangement of the slow wave structure in a 12-cavity relativistic magnetron with diffraction output using single-stepped cavities driven by a transparent cathode
Authors: Li Y. , Liu M. , Liu C. , Feng J. , Schamiloglu E. , Fuks M. I. , Jiang W. , Li F. , Han J. , Yang X. 
Published: March 2021

We present the design of an agile slow wave structure for a “crab-like” A12 relativistic magnetron with diffraction output using single-stepped cavities. By regrouping the interaction region as three sets of four cavities, the TE31 operating mode is generated at 2.60 GHz with 1.0 GW output power for an applied voltage of U = 350 kV and a magnetic field of B = 0.34 T. By regrouping the interaction region as four sets of three cavities, the TE41 operating mode is generated at 2.82 GHz with 1.0 GW output power for an applied voltage of U = 355 kV and a magnetic field of B = 0.36 T. Furthermore, by regrouping the interaction region as six sets of two cavities, the TE31 mode and the TE21 mode are generated. When an applied voltage of U = 350 kV and a magnetic field of B = 0.33 T are used, its output power can be as high as 1.0 GW for the TE31 mode operating at 2.5 GHz. In addition, when an applied voltage of U = 350 kV and a magnetic field of B = 0.42 T are used, its output power can be as high as 1.0 GW with operating mode TE21 at 2.62 GHz. It was found that the rearrangement of the slow wave structure can control the operating mode and, at the same time, lower the operating condition of the beam/wave interaction compared to the traditional 12-cavity relativistic magnetron. The result suggests that this configuration is favorable for mode switching through mechanical rearrangement of the slow wave structure. This work seeks to design a compact high power microwave source for a narrowband directed microwave beam that is suitable for mode switching investigations.
Development of an indirect thrust stand based on a cantilever beam
Authors: Zhang H. , Li D. T. , He F. , Chen X. W. 
Published: March 2021

There is a large number of missions that have been or will be launched soon that utilize the electric propulsion (EP), which is considered a key technology for applications in present and future space missions. Accomplishing an accurate measure of the thrust is a key aspect of the laboratory verification of EP systems. In the case of ground conditions and direct measurements, it is complicated to verify the thrusters, especially for some high power (&gt;5 kW) thrusters. For this reason, we have developed an indirect method for measuring thrust. We have carried out an experiment with a Hall effect thruster (operated in the 250 W power range) and compared results against direct thrust measurements. The difficulties in the indirect measurement are analyzed, which provides a basis for the development of indirect thrust measurement.
Analyzing the magnetic interactions in nanostructures that are candidates for applications in spintronics
Authors: Holanda José 
Published: March 2021

Abstract
It is very common for the qualitative study of magnetic interactions in nanostructures to lead to applications in spintronics. In this paper, a model is presented to calculate the magnetic interactions in nanostructures. The model can determine quantitative values for the types of magnetic states in the sample, which can be demagnetized or magnetized. Each magnetic interaction provides information on the magnetic behavior of the nanostructure and opens possibilities for spin-wave excitations. For the model application, numerical simulations were carried out on nanostructures of type nanowires and hexagonal nanowire arrays. Each nanowire is one chain of interacting ellipsoidal grains.
The ‘dark phase’ in Sr2Ir1−x
Rh
x
O4 revealed by Seebeck and Hall measurements
Authors: Fruchter L , Brouet V 
Published: March 2021

Abstract
It was found that, although isovalent, Rh substituted for Ir in Sr2IrO4 may trap one electron inducing effective hole doping of Ir sites. Transport and thermoelectric measurements on Sr2Ir1−x
Rh
x
O4 single crystals presented here reveal the existence of an electron-like contribution to transport, in addition to the hole-doped one. As no electron band shows up in ARPES measurements, this points to the possibility that this hidden electron may delocalize in disordered clusters.
Low-temperature processed tantalum/niobium co-doped TiO2 electron transport layer for high-performance planar perovskite solar cells
Authors: Duan Yanyan , Zhao Gen , Liu Xiaotao , Ma Jiale , Chen Shuyao , Song Yanlin , Pi Xiaodong , Yu Xuegong , Yang Deren , Zhang Yiqiang , Guo Feng 
Published: March 2021

Abstract
A low-temperature preparation process is significantly important for scalable and flexible devices. However, the serious interface defects between the normally used titanium dioxide (TiO2) electron transport layer (ETL) obtained via a low-temperature method and perovskite suppress the further improvement of perovskite solar cells (PSCs). Here, we develop a facile low-temperature chemical bath method to prepare a TiO2 ETL with tantalum (Ta) and niobium (Nb) co-doping. Systematic investigations indicate that Ta/Nb co-doping could increase the conduction band level of TiO2 and could decrease the trap-state density, boosting electron injection efficiency and reducing the charge recombination between the perovskite/ETL interface. A superior power conversion efficiency of 19.44% can be achieved by a planar PSC with a Ta/Nb co-doped TiO2 ETL, which is much higher than that of pristine TiO2 (17.60%). Our achievements in this work provide new insights on low-temperature fabrication of low-cost and highly efficient PSCs.
Spin-Seebeck effect and thermal colossal magnetoresistance in the narrowest zigzag graphene nanoribbons
Authors: Wu Dan-Dan , Fu Hua-Hua 
Published: March 2021

Abstract
Device miniaturization and low-energy dissipation are two urgent requirements in future spintronics devices. The narrowest zigzag graphene nanoribbons (ZGNRs), which are composed of just two coupled carbon-atom chains connected with carbon tetragons, are promising candidates that meet both of the above requirements well. Using the first-principles calculations combined with non-equilibrium Green’s function approach, thermal spin-dependent transport through this kind of narrow ZGNR is investigated, and several exotic thermal spin-resolved transport properties are uncovered: (i) when an external magnetic field is applied, the ZGNRs are transited from the intrinsic semiconducting to the metallic state, and the thermal colossal magnetoresistance effect occurs with order of magnitudes up to 104 at room temperature; (ii) the thermal spin-dependent currents display a thermal negative differential resistance effect, and a well-defined spin-Seebeck effect (SSE) together with a pure thermal spin current occurs; and (iii) under suitable device temperature settings, a nearly perfect spin-filtering effect occurs in these narrowest ZGNRs. The theoretical results not only uncover the narrowest nanoribbon structures to realize the SSE and other inspiring thermal spin transport features, but also push carbon-based material candidates towards thermoelectric conversion device applications.
Controlled electron transmission by lead chalcogenide barrier potential
Authors: Pfeffer P , Zawadzki W , Dybko K 
Published: March 2021

Abstract
Transmission of electrons across a rectangular barrier of IV–VI semiconductor compounds is considered. Conduction electrons arrive at the barrier and are reflected or transmitted through it depending on the relative values of the barrier potential V

b
and the electron energy E. The theory, in close analogy to the Dirac four component spinors, accounts for the boundary conditions on both sides of the barrier. The calculated transmission coefficient TC
is an oscillatory function of the barrier voltage varying between zero (for full electron reflection) and unity (for full electron transmission). Character of electron wave functions outside and inside the barrier is studied. There exists a total current conservation, i.e. the sum of transmitted and reflected currents is equal to the incoming current. The transmission TC
is studied for various barrier widths and incoming electron energies. Finally, the transmission coefficient TC
is studied as a function of V

b
for decreasing energy gaps E

g
of different Pb1 − x
Sn
x
Se compounds in the range of 150 meV

⩾

E
g

⩾

2 meV. It is indicated that for very small gap values the behavior of TC
closely resembles that of the chiral electron tunneling by a barrier in monolayer graphene. For E

g
= 0 (Pb0.81Sn0.19Se) the coefficient TC
reaches the value of 1 independently of V

b
.
Optimizing autonomous thermal machines powered by energetic coherence
Authors: Hammam Kenza , Hassouni Yassine , Fazio Rosario , Manzano Gonzalo 
Published: March 2021

Abstract
The characterization and control of quantum effects in the performance of thermodynamic tasks may open new avenues for small thermal machines working in the nanoscale. We study the impact of coherence in the energy basis in the operation of a small thermal machine which can act either as a heat engine or as a refrigerator. We show that input coherence may enhance the machine performance and allow it to operate in otherwise forbidden regimes. Moreover, our results also indicate that, in some cases, coherence may also be detrimental, rendering optimization of particular models a crucial task for benefiting from coherence-induced enhancements.
Improving Spectrum Sensing Under Impact of Noise Uncertainty Factor to Detect Primary User Traffic for Cognitive Radio System
Authors: Wotaif Akil H. , Hamza Bashar J. , Saad Wasan Kadhim 
Published: March 2021

Abstract
Nowadays, users of wireless communication networks are facing a challenge and a shortage in allocating the radio spectrum, as a result of the rapid and widespread development in the wireless field. A major cause of this scarcity is the reliance on the strategy and policy of distribution or fixed allocation of the radio spectrum, as it is a natural and limited source. Cognitive radio is the best system to deal with the scarcity of the radio spectrum at the present time, as the idea of this system is to allow secondary or unauthorized users to use the spectrum in times it is not used by the primary of authorized users. This use is made conditionally without affecting the original users. The spectrum sensing function is one of the most important functions of the cognitive radio system and is the essence of its work. The traditional methods have proven ineffective in sensing and detecting the dynamic primary user, due to its assumptions that either the primary user is totally present or completely absent, as well as neglecting the reuse of the spectrum again. The main objective of this research is to suggest an algorithm to improve the detection process and reduce sensing time. The efficiency of spectrum sensing is improved through the use of a dynamic threshold. The new work in this scheme is the modeling of the primary dynamic user signal called Activity period (A) which presents a more realistic modeling and dynamic threshold together. The signal-to-noise ratio was used low to some extent, this is to ensure the quality of communication services. Consequently, the simulation results clearly prove that the proposed scheme achieves and meets the sensing enhancing requirements much better than many other sensing technologies.