bluuebunny/crossref_metadata_2025 huggingface dataset:
Pure tone discrimination with cochlear implants and filter-band spread
Authors: Wagner Luise , Altindal Reyhan , Plontke Stefan K. , Rahne Torsten
Published: October 2021

For many cochlear implant (CI) users, frequency discrimination is still challenging. We studied the effect of frequency differences relative to the electrode frequency bands on pure tone discrimination. A single-center, prospective, controlled, psychoacoustic exploratory study was conducted in a tertiary university referral center. Thirty-four patients with Cochlear Ltd. and MED-EL CIs and 19 age-matched normal-hearing control subjects were included. Two sinusoidal tones were presented with varying frequency differences. The reference tone frequency was chosen according to the center frequency of basal or apical electrodes. Discrimination abilities were psychophysically measured in a three-interval, two-alternative, forced-choice procedure (3I-2AFC) for various CI electrodes. Hit rates were measured, particularly with respect to discrimination abilities at the corner frequency of the electrode frequency-bands. The mean rate of correct decision concerning pitch difference was about 60% for CI users and about 90% for the normal-hearing control group. In CI users, the difference limen was two semitones, while normal-hearing participants detected the difference of one semitone. No influence of the corner frequency of the CI electrodes was found. In CI users, pure tone discrimination seems to be independent of tone positions relative to the corner frequency of the electrode frequency-band. Differences of 2 semitones can be distinguished within one electrode.
Impact of thermal radiation and non-uniform heat flux on MHD hybrid nanofluid along a stretching cylinder
Authors: Ali Aamir , Kanwal Tasmia , Awais Muhammad , Shah Zahir , Kumam Poom , Thounthong Phatiphat
Published: October 2021

The current research investigates the thermal radiations and non-uniform heat flux impacts on magnetohydrodynamic hybrid nanofluid (CuO-Fe2O3/H2O) flow along a stretching cylinder, which is the main aim of this study. The velocity slip conditions have been invoked to investigate the slippage phenomenon on the flow. The impact of induced magnetic field with the assumption of low Reynolds number is imperceptible. Through the use of appropriate non-dimensional parameters and similarity transformations, the ruling PDE’s (partial differential equations) are reduced to set of ODE’s (ordinary differential equations), which are then numerically solved using Adams–Bashforth Predictor–Corrector method. Velocity and temperature fields with distinct physical parameters are investigated and explored graphically. The main observations about the hybrid nanofluid and non-uniform heat flux are analyzed graphically. A decrease in the velocity of the fluid is noted with addition of Hybrid nanofluid particles while temperature of the fluid increases by adding the CuO-Fe2O3 particles to the base fluid. Also, velocity of the fluid decreases when we incorporate the effects of magnetic field and slip. Raise in curvature parameter γ caused enhancement of velocity and temperature fields at a distance from the cylinder but displays opposite behavior nearby the surface of cylinder. The existence of heat generation and absorption for both mass dependent and time dependent parameters increases the temperature of the fluid.
Evaluation of digital watermarking on subjective speech quality
Authors: Kowalczuk Yann , Holub Jan
Published: October 2021

New methods of securing the distribution of audio content have been widely deployed in the last twenty years. Their impact on perceptive quality has, however, only been seldomly the subject of recent extensive research. We review digital speech watermarking state of the art and provide subjective testing of watermarked speech samples. Latest speech watermarking techniques are listed, with their specifics and potential for further development. Their current and possible applications are evaluated. Open-source software designed to embed watermarking patterns in audio files is used to produce a set of samples that satisfies the requirements of modern speech-quality subjective assessments. The patchwork algorithm that is coded in the application is mainly considered in this analysis. Different watermark robustness levels are used, which allow determining the threshold of detection to human listeners. The subjective listening tests are conducted following ITU-T P.800 Recommendation, which precisely defines the conditions and requirements for subjective testing. Further analysis tries to determine the effects of noise and various disturbances on watermarked speech’s perceived quality. A threshold of intelligibility is estimated to allow further openings on speech compression techniques with watermarking. The impact of language or social background is evaluated through an additional experiment involving two groups of listeners. Results show significant robustness of the watermarking implementation, retaining both a reasonable net subjective audio quality and security attributes, despite mild levels of distortion and noise. Extended experiments with Chinese listeners open the door to formulate a hypothesis on perception variations with geographical and social backgrounds.
Humans in the upstream can exacerbate climate change impacts on water birds’ habitat in the downstream
Authors: Maleki Saeideh , Rahdari Vahid , Baghdadi Nicolas
Published: October 2021

The present paper aims to quantify how human-made changes in the upstream exacerbate climate change impacts on water birds’ habitat in the downstream. To reduce climate change effects and design adaptation policies, it is important to identify whether human activities understate or overstate the effects of climate change in a region on its inhabitants. This paper also shows how human activities may magnify climate change impacts both locally and regionally. Land-use/land-cover change as the important sign of human-made destruction in an ecosystem was detected in the upstream of the Helmand basin over 40 years. Owing to conflicts in Afghanistan, studies on this basin are rare. The water bird’s habitat suitability maps during the study period were created using the maximum entropy model and the multi-criteria evaluation method. The post-classification method was applied to show the land-use/land-cover change over 40 years. These results were compared to the area of suitable habitat for water birds. The findings of these analyses indicated that the irrigated farming was expanded in the upstream despite climate change and water limitation, while the water birds’ habitat in the downstream was declined. These results revealed that the unsustainable pattern of farming and blocking water behind dams in the upstream exacerbated the negative effects of climate change on water birds’ habitat in the downstream. The significance of this study is to demonstrate the role of human in exacerbating climate change impacts both locally and regionally.
Accurate and semi-automated reassociation of intermixed human skeletal remains recovered from bioarchaeological and forensic contexts
Authors: Anastopoulou Ioanna , Karakostis Fotios Alexandros , Harvati Katerina , Moraitis Konstantinos
Published: October 2021

Commingled remains describes the situation of intermixed skeletal elements, an extremely common occurrence in contemporary forensic cases, archaeological mass graves, as well as fossil hominin assemblages. Given that reliable identification is typically impossible for commingled contexts, a plethora of previous studies has focused on the development of refined methods for reassociating the bones of each individual skeleton. Here, a novel virtual approach for quantifying the degree of three-dimensional shape compatibility between two adjoining bone articular surfaces is put forth. Additionally, the integrability of this method with traditional osteometric techniques is evaluated. We focus on the paradigm of the hip joint, whose articulating bone elements (the femur and the innominate bone) are crucial for reconstructing the biological profile of unidentified human remains. The results demonstrate that this new semi-automated methodology is highly accurate both for large commingled assemblages (such as those resulting from mass disasters or burials) as well as smaller-scale contexts (such as those resulting from secondary burials).
Capturing convection essential for projections of climate change in African dust emission
Authors: Garcia-Carreras Luis , Marsham John H. , Stratton Rachel A. , Tucker Simon
Published: October 2021

The summertime Sahara and Sahel are the world’s largest source of airborne mineral dust. Cold-pool outflows from moist convection (‘haboobs’) are a dominant source of summertime uplift but are essentially missing in global models, raising major questions on the reliability of climate projections of dust and dust impacts. Here we use convection-permitting simulations of pan-African climate change, which explicitly capture haboobs, to investigate whether this key limitation of global models affects projections. We show that explicit convection is key to capturing the observed summertime maximum of dust-generating winds, which is missed with parameterised convection. Despite this, future climate changes in dust-generating winds are more sensitive to the effects of explicit convection on the wider meteorology than they are to the haboobs themselves, with model differences in the change in dust-generating winds reaching 60% of current values. The results therefore show the importance of improving convection in climate models for dust projections.
Nuclear preservation in the cartilage of the Jehol dinosaur Caudipteryx
Authors: Zheng Xiaoting , Bailleul Alida M. , Li Zhiheng , Wang Xiaoli , Zhou Zhonghe
Published: October 2021

Previous findings on dinosaur cartilage material from the Late Cretaceous of Montana suggested that cartilage is a vertebrate tissue with unique characteristics that favor nuclear preservation. Here, we analyze additional dinosaur cartilage inCaudipteryx(STM4-3) from the Early Cretaceous Jehol biota of Northeast China. The cartilage fragment is highly diagenetically altered when observed in ground-sections but shows exquisite preservation after demineralization. It reveals transparent, alumino-silicified chondrocytes and brown, ironized chondrocytes. The histochemical stain Hematoxylin and Eosin (that stains the nucleus and cytoplasm in extant cells) was applied to both the demineralized cartilage ofCaudipteryxand that of a chicken. The two specimens reacted identically, and one dinosaur chondrocyte revealed a nucleus with fossilized threads of chromatin. This is the second example of fossilized chromatin threads in a vertebrate material. These data show that some of the original nuclear biochemistry is preserved in this dinosaur cartilage material and further support the hypothesis that cartilage is very prone to nuclear fossilization and a perfect candidate to further understand DNA preservation in deep time.
Label-free enrichment of rare unconventional circulating neoplastic cells using a microfluidic dielectrophoretic sorting device
Authors: Montoya Mira Jose , Sapre Ajay A. , Walker Brett S. , Alvarez Jesus Bueno , Gustafson Kyle T. , Tu Eugene , Fischer Jared M. , Wong Melissa H. , Esener Sadik , Chiu Yu-Jui
Published: October 2021

Cellular circulating biomarkers from the primary tumor such as circulating tumor cells (CTCs) and circulating hybrid cells (CHCs) have been described to harbor tumor-like phenotype and genotype. CHCs are present in higher numbers than CTCs supporting their translational potential. Methods for isolation of CHCs do not exist and are restricted to low-throughput, time consuming, and biased methodologies. We report the development of a label-free dielectrophoretic microfluidic platform facilitating enrichment of CHCs in a high-throughput and rapid fashion by depleting healthy peripheral blood mononuclear cells (PBMCs). We demonstrated up to 96.5% depletion of PBMCs resulting in 18.6-fold enrichment of cancer cells. In PBMCs from pancreatic adenocarcinoma patients, the platform enriched neoplastic cells identified by their KRAS mutant status using droplet digital PCR with one hour of processing. Enrichment was achieved in 75% of the clinical samples analyzed, establishing this approach as a promising way to non-invasively analyze tumor cells from patients.
Multivariate analysis reveals shared genetic architecture of brain morphology and human behavior
Authors: de Vlaming Ronald , Slob Eric A. W. , Jansen Philip R. , Dagher Alain , Koellinger Philipp D. , Groenen Patrick J. F. , Rietveld Cornelius A.
Published: October 2021

Human variation in brain morphology and behavior are related and highly heritable. Yet, it is largely unknown to what extent specific features of brain morphology and behavior are genetically related. Here, we introduce a computationally efficient approach for multivariate genomic-relatedness-based restricted maximum likelihood (MGREML) to estimate the genetic correlation between a large number of phenotypes simultaneously. Using individual-level data (N = 20,190) from the UK Biobank, we provide estimates of the heritability of gray-matter volume in 74 regions of interest (ROIs) in the brain and we map genetic correlations between these ROIs and health-relevant behavioral outcomes, including intelligence. We find four genetically distinct clusters in the brain that are aligned with standard anatomical subdivision in neuroscience. Behavioral traits have distinct genetic correlations with brain morphology which suggests trait-specific relevance of ROIs. These empirical results illustrate how MGREML can be used to estimate internally consistent and high-dimensional genetic correlation matrices in large datasets.
Designing narcissistic self-sorting terpyridine moieties with high coordination selectivity for complex metallo-supramolecules
Authors: Ma Jianjun , Lu Tong , Duan Xiaozheng , Xu Yaping , Li Zhikai , Li Kehuan , Shi Junjuan , Bai Qixia , Zhang Zhe , Hao Xin-Qi , Chen Zhi , Wang Pingshan , Wang Ming
Published: October 2021

Coordination-driven self-assembly is a powerful approach for the construction of metallosupramolecules, but designing coordination moieties that can drive the self-assembly with high selectivity and specificity remains a challenge. Here we report two ortho-modified terpyridine ligands that form head-to-tail coordination complexes with Zn(II). Both complexes show narcissistic self-sorting behaviour. In addition, starting from these ligands, we obtain two sterically congested multitopic ligands and use them to construct more complex metallo-supramolecules hexagons. Because of the non-coaxial structural restrictions in the rotation of terpyridine moieties, these hexagonal macrocycles can hierarchically self-assemble into giant cyclic nanostructures via edge-to-edge stacking, rather than face-to-face stacking. Our design of dissymmetrical coordination moieties from congested coordination pairs show remarkable self-assembly selectivity and specificity.
Detecting informative higher-order interactions in statistically validated hypergraphs
Authors: Musciotto Federico , Battiston Federico , Mantegna Rosario N.
Published: October 2021

Recent empirical evidence has shown that in many real-world systems, successfully represented as networks, interactions are not limited to dyads, but often involve three or more agents at a time. These data are better described by hypergraphs, where hyperlinks encode higher-order interactions among a group of nodes. In spite of the extensive literature on networks, detecting informative hyperlinks in real world hypergraphs is still an open problem. Here we propose an analytic approach to filter hypergraphs by identifying those hyperlinks that are over-expressed with respect to a random null hypothesis, and represent the most relevant higher-order connections. We apply our method to a class of synthetic benchmarks and to several datasets, showing that the method highlights hyperlinks that are more informative than those extracted with pairwise approaches. Our method provides a first way, to the best of our knowledge, to obtain statistically validated hypergraphs, separating informative connections from noisy ones.
Matryoshka phonon twinning in α-GaN
Authors: Wei Bin , Cai Qingan , Sun Qiyang , Su Yaokun , Said Ayman H. , Abernathy Douglas L. , Hong Jiawang , Li Chen
Published: October 2021

Understanding lattice dynamics is crucial for effective thermal management in electronic devices because phonons dominate thermal transport in most semiconductors. α-GaN has become a focus of interest as one of the most important third-generation power semiconductors, however, the knowledge on its phonon dynamics remains limited. Here we show a Matryoshka phonon dispersion of α-GaN with the complementary inelastic X-ray and neutron scattering techniques and the first-principles calculations. Such Matryoshka twinning throughout the basal plane of the reciprocal space is demonstrated to amplify the anharmonicity of the related phonons through creating abundant three-phonon scattering channels and cutting the lifetime of affected modes by more than 50%. Such phonon topology contributes to reducing the in-plane thermal transport, thus the anisotropic thermal conductivity of α-GaN. The results not only have implications for engineering the thermal performance of α-GaN, but also offer valuable insights on the role of anomalous phonon topology in thermal transport of other technically semiconductors.
Surface-induced dissociation of protein complexes on a cyclic ion mobility spectrometer
Authors: Snyder Dalton T. , Jones Benjamin J. , Lin Yu-Fu , Cooper-Shepherd Dale A. , Hewitt Darren , Wildgoose Jason , Brown Jeffery M. , Langridge James I. , Wysocki Vicki H.
Published: October 2021

Characterization of protein assemblies and amyloid aggregates by CIU, CID, SIU, and SID on a cyclic ion mobility spectrometer.
Synthesis and grafting of diazonium tosylates for thermoplastic electrode immunosensors
Authors: McCord Cynthia P. , Ozer Tugba , Henry Charles S.
Published: October 2021

Diazonium modified thermoplastic electrode were successfully used to perform sandwich ELISA immunoassays for detection of C-reactive protein in both buffer and serum with clinically relevant LODs.
A high performance Pb(ii) electrochemical sensor based on spherical CuS nanoparticle anchored g-C3N4
Authors: Ning Jingheng , Wei Jiaqian , Huang Shouen , Wang Faxiang , Luo Xin , Sun Chang , Chen Donger , Wei Rui , Sha Liming , Liu Yongle
Published: October 2021

Highly efficient electrochemical detection of Pb2+ is achieved by the composite CuS/g-C3N4, based on a synergistic effect of “coordination/adsorption” on Pb2+ provided by both g-C3N4 and CuS. The limit of detection is as low as 4 nM.
Switching the aptamer attachment geometry can dramatically alter the signalling and performance of electrochemical aptamer-based sensors
Authors: Chamorro-Garcia Alejandro , Ortega Gabriel , Mariottini Davide , Green Joshua , Ricci Francesco , Plaxco Kevin W.
Published: October 2021

Switching which termini the redox reporter and surface-anchoring thiol are on, in electrochemical aptamer-based sensors, significantly alters their performance.
Alumination of aryl methyl ethers: switching between sp2 and sp3 C–O bond functionalisation with Pd-catalysis
Authors: Brown Ryan K. , Hooper Thomas N. , Rekhroukh Feriel , White Andrew J. P. , Costa Paulo J. , Crimmin Mark R.
Published: October 2021

The selectivity of the reaction of a low-valent aluminium reagent with aryl methyl ethers can be controlled by a catalyst.
Twisted intramolecular charge transfer (TICT) and twists beyond TICT: from mechanisms to rational designs of bright and sensitive fluorophores
Authors: Wang Chao , Chi Weijie , Qiao Qinglong , Tan Davin , Xu Zhaochao , Liu Xiaogang
Published: October 2021

The twisted intramolecular charge transfer (TICT) mechanism and twists beyond TICT have guided the creation of numerous bright and sensitive fluorophores. We reviewed the structure–property relationships of these dyes with representative examples.
Gas electron diffraction then and now: from trisilyl phosphine to iso-propyl(tert-butyl)(trichlorosilyl)phosphine
Authors: Wagner Isabella , Rankin David W. H. , Masters Sarah L.
Published: October 2021

GED has evolved hugely in the 50 years of Dalton Transactions. Combining experimental and theoretical data now allows complicated structures free from intermolecular interactions like iso-propyl(tert-butyl)(trichlorosilyl)phosphine to be revealed.
An innovative light assisted production of acetic acid from CO2and methanol: a first photocatalytic approach using a reusable cobalt(ii) molecular hybrid at atmospheric pressure
Authors: Saini Sandhya , Samal Pragnya paramita , Krishnamurty Sailaja , Ray Anjan , Jain Suman L.
Published: October 2021

Acetic acid is an important commodity chemical that is produced either by fermentation processes, or more commonly, through chemical routes such as methanol carbonylation with CO and H2, acetaldehyde oxidation, or hydrocarbon oxidation.
Valorisation of technical lignin in rigid polyurethane foam: a critical evaluation on trends, guidelines and future perspectives
Authors: Haridevan Hima , Evans David A. C. , Ragauskas Arthur J. , Martin Darren J. , Annamalai Pratheep K.
Published: October 2021

Lignin is an inexpensive raw material that can be utilised in polymer industry. This review critically appraises the recent progress and provides framework for future developments in lignin valorisation into rigid polyurethane foam.
Electrochemically enabled rhodium-catalyzed [4 + 2] annulations of arenes with alkynes
Authors: Wang Zi-Chen , Li Rui-Tao , Ma Qiang , Chen Jia-Yi , Ni Shao-Fei , Li Ming , Wen Li-Rong , Zhang Lin-Bao
Published: October 2021

Herein, electrochemically driven, Rh(iii)-catalyzed regioselective annulations of arenes with alkynes have been established.
Virus removal from semen with a pinched flow fractionation microfluidic chip
Authors: Hamacher T. , Berendsen J. T. W. , van Dongen J. E. , van der Hee R. M. , Cornelissen J. J. L. M. , Broekhuijse M. L. W. J. , Segerink L. I.
Published: October 2021

Pinched-flow fractionation removes viruses from (porcine) semen, which can increase the biosecurity of artificial insemination.
Balanced infrared nonlinear optical performance achieved by modulating the covalency and ionicity distributions in the electron localization function map
Authors: Liu Bin-Wen , Jiang Xiao-Ming , Pei Shao-Min , Chen Wen-Fa , Yang Long-Qi , Guo Guo-Cong
Published: October 2021

Phenomenological rules between the topological feature of the electron localization function and the nonlinear optical (NLO) performance were extracted to design new superior infrared NLO sulfides with a balanced NLO efficiency and laser-induced damage threshold.
Fabrication of ternary composites with polymeric carbon nitride/MoS2/reduced graphene oxide ternary hybrid aerogel as high-performance electrode materials for supercapacitors
Authors: Xavier Marilyn Mary , Mohanapriya S. , Mathew Reshma , Adarsh Nayarassery N. , Nair P. Radhakrishnan , Mathew Suresh
Published: October 2021

Presenting a remarkable ternary hybrid aerogel, as an excellent electrode material with a specific capacitance of 467 Fg−1 and capacitance retention upto 80.4% even after 2000 cycles, demonstrating good stability and improved cyclic performance.
The role of mono- and dicarboxylic acids in the building of oxomolybdates containing {MoO4}, {Mo2O5}, {Mo2O6}, {Mo3O8}, {Mo5O17}, {Mo5O18}, {Mo8O26}, and {SiMo12O40} units
Authors: Kuzman Dino , Damjanović Vladimir , Stilinović Vladimir , Cindrić Marina , Vrdoljak Višnja
Published: October 2021

We describe the impact of mono- and dicarboxylic acids on the formation of polyoxomolybdates of different nuclearities, such as {Mo5O17}, {Mo5O18}, {Mo8O26}, and {SiMo12O40}.
The formation mechanism of cerium-bearing aerosols with the aid of chemical explosions in airtight scenarios
Authors: Xie Bo , Long Xinggui , Hu Sheng
Published: October 2021

The formations of Ce-bearing aerosols from different materials, including CeO2, Ce powder and Ce tablet, via chemical explosive reactions.
Boosting the comprehensive performance for a Co-free high-voltage system with a multi-component nitrile
Authors: Zhang Ping , Li Shi-You , Wei Xiao-Hong , Li Chun-Lei , Meng Shu-Juan , Cui Xiao-Ling , Su Qiong , Zhao Dong-Ni
Published: October 2021

We use HTN to improve the high voltage resistance of LNMO-based cells without affecting the viscosity of the electrolyte.
Exploring the electronic band gap of Janus MoSeO and WSeO monolayers and their heterostructures
Authors: Van On Vo , Nguyen Duy Khanh , Guerrero-Sanchez J. , Hoat D. M.
Published: October 2021

Electronic band structure of TMSeO monolayers.
Combination of DNA demethylation and chemotherapy to trigger cell pyroptosis for inhalation treatment of lung cancer
Authors: Xie Beibei , Liu Tingting , Chen Shuang , Zhang Yan , He Dongxian , Shao Qian , Zhang Zhen , Wang Chenhui
Published: October 2021

Inhaled PLGA porous microspheres loaded with Decitabine (DAC) and Doxorubicin (DOX) were prepared to induce cell pyroptosis for orthotopic lung cancer therapy with fewer systemic side effects.
Synthesis and anionic polymerization of isosorbide mono-epoxides for linear biobased polyethers
Authors: Matt Livia , Liblikas Ilme , Bonjour Olivier , Jannasch Patric , Vares Lauri
Published: October 2021

Different regioisomeric and diastereomeric isosorbide mono-epoxides are prepared and polymerized to thermally stable and relatively rigid biobased linear polyethers.
Propylene homopolymerization and copolymerization with ethylene by acenaphthene-based α-diimine nickel complexes to access EPR-like elastomers
Authors: Wang Beibei , Liu Heng , Zhang Chunyu , Tang Tao , Zhang Xuequan
Published: October 2021

A series of acenaphthene-based α-diimine nickel complexes were synthesized and subsequently used for accessing branched EPR-like elastomers with different compositions and chain structures.
Aufbau vs. non-Aufbau ground states in two-coordinate d7 single-molecule magnets
Authors: Errulat Dylan , Harriman Katie L. M. , Gálico Diogo A. , Ovens Jeffrey S. , Mansikkamäki Akseli , Murugesu Muralee
Published: October 2021

Magnetic anisotropy is generated in two related d7 single-molecule magnets; (1) via 3d-4s orbital mixing in FeI; and (2) a non-Aufbau ground state in CoII, demonstrating that the electronic configurations are large retained independent of geometry.
Catalytic radical cascade cyclization of alkene-tethered enones to fused bicyclic cyclopropanols
Authors: Xie Ying , Huang Wei , Qin Song , Fu Shaomin , Liu Bo
Published: October 2021

Fused bicyclic cyclopropanols were achieved via an unprecedented HAT-triggered radical cascade reaction of alkene-tethered enones in the presence of an iron catalyst.
Retraction: Carbon black hybrid material furnished monodisperse platinum nanoparticles as highly efficient and reusable electrocatalysts for formic acid electro-oxidation
Authors: Fisher Laura
Published: October 2021

Retraction of ‘Carbon black hybrid material furnished monodisperse platinum nanoparticles as highly efficient and reusable electrocatalysts for formic acid electro-oxidation’ by Yunus Yıldız et al., RSC Adv., 2016, 6, 32858–32862, DOI: 10.1039/C6RA00232C
Retraction: Monodispersed palladium–cobalt alloy nanoparticles assembled on poly(N-vinyl-pyrrolidone) (PVP) as a highly effective catalyst for dimethylamine borane (DMAB) dehydrocoupling
Authors: Fisher Laura
Published: October 2021

Retraction of ‘Monodispersed palladium–cobalt alloy nanoparticles assembled on poly(N-vinyl-pyrrolidone) (PVP) as a highly effective catalyst for dimethylamine borane (DMAB) dehydrocoupling’ by Betül Çelik et al., RSC Adv., 2016, 6, 24097–24102, DOI: 10.1039/c6ra00536e.
Correction: Sensitive MnFe2O4–Ag hybrid nanoparticles with photothermal and magnetothermal properties for hyperthermia applications
Authors: Nha T. T. N. , Nam P. H. , Phuc N. X. , Nguyen V. Q. , Nam N. H. , Manh D. H. , Tam L. T. , Linh N. T. N. , Khanh B. T. V. , Lu L. T. , Nguyen L. H. , Phong P. T.
Published: October 2021

Correction for ‘Sensitive MnFe2O4–Ag hybrid nanoparticles with photothermal and magnetothermal properties for hyperthermia applications’ by T. T. N. Nha et al., RSC Adv., 2021, 11, 30054–30068. DOI: 10.1039/D1RA03216J
Aptamer-modified DNA tetrahedra-gated metal–organic framework nanoparticle carriers for enhanced chemotherapy or photodynamic therapy
Authors: Zhang Pu , Fischer Amit , Ouyang Yu , Wang Jianbang , Sohn Yang Sung , Nechushtai Rachel , Pikarsky Eli , Fan Chunhai , Willner Itamar
Published: October 2021

UiO-66 metal–organic framework nanoparticles (NMOFs) gated by aptamer-functionalized DNA tetrahedra provide superior biomarker-responsive hybrid nano-carriers for biomedical applications.
A novel Ba0.95La0.05Fe0.9Nb0.1O3−δ ceramic electrode for symmetrical solid oxide fuel cells
Authors: Li Zhongbiao , Wang Jinpeng , Zhu Jiangpeng , Sun Yanjun , Wang Zhihao , Zhao Yujun , Wei Zhaoling , Zhu Zhiwen , Zheng Qiuju
Published: October 2021

The Ba0.95La0.05Fe0.9Nb0.1O3−δ electrode provides a unique combination of good tolerance for H2-reduction and low polarization resistances for the oxygen reduction reaction and hydrogen oxidation reaction.
Stabilizing oxygen intermediates on redox-flexible active sites in multimetallic Ni–Fe–Al–Co layered double hydroxide anodes for excellent alkaline and seawater electrolysis
Authors: Enkhtuvshin Enkhbayar , Kim Kang Min , Kim Young-Kwang , Mihn Sungwook , Kim So Jung , Jung Sun Young , Thu Thao Nguyen Thi , Ali Ghulam , Akbar Muhammad , Chung Kyung Yoon , Chae Keun Hwa , Kang Sukhyun , Lee Taeg Woo , Kim Hyung Giun , Choi Seunggun , Han HyukSu
Published: October 2021

Quaternary multimetallic LDHs have been developed through a facile metal–organic-framework derived electrochemical activation process. Ni–Fe–Al–Co quaternary LDHs show one of the best OER performances in alkaline and seawater electrolytes.
Template-free synthesis of a yolk–shell Co3O4/nitrogen-doped carbon microstructure for excellent lithium ion storage
Authors: Xiao Ming-Jun , Zhang Hong , Ma Bo , Zhang Ze-Qi , Li Xiang-Yang , Xiao Qi , Wang Qiang , Peng Yong , Zhang Hao-Li
Published: October 2021

We reported a facile synthetic method to prepare open yolk–shell microstructure materials assembled from Co3O4/NDC nanoparticles, which show excellent reversible capacity and rate performance.
TADF: Enabling luminescent copper(i) coordination compounds for light-emitting electrochemical cells
Authors: Housecroft Catherine E. , Constable Edwin C.
Published: October 2021

In this review, we illustrate how the field of luminescent copper(i) compounds has developed with a focus on ionic copper(i) complexes and those exhibiting thermally-activated delayed fluorescence (TADF).
Understanding the dopant induced effects on SFX-MeOTAD for perovskite solar cells: a spectroscopic and computational investigation
Authors: Gunn Fraser , Ghosh Paheli , Maciejczyk Michal , Cameron Joseph , Nordlund Dennis , Krishnamurthy Satheesh , Tuttle Tell , Skabara Peter , Robertson Neil , Ivaturi Aruna
Published: October 2021

First-time spectroscopic and computational investigations to elucidate the role of a dicationic salt in the optical, electrical and electronic properties of a triarylamine hole transport material, SFX-MeOTAD.
Sputter‐grown GeTe/Sb2Te3 superlattice interfacial phase change memory for low power and multi‐level‐cell operation
Authors: Jin Soo‐Min , Kang Shin‐Young , Kim Hea‐Jee , Lee Ju‐Young , Nam In‐Ho , Shim Tae‐Hun , Song Yun‐Heub , Park Jea‐Gun
Published: October 2021

The multi‐level feature of GeTe/Sb2Te3 interfacial phase change memory was achieved by applying a designed voltage‐based pulse. It stably demonstrated five multi‐level states without interference for 90 cycles by varying the pulse width. GeTe/Sb2Te3 interfacial phase change memory demonstrated retention time of > 1.0 × 103 s, presenting the significantly low drift coefficient (ν) of < 0.009, indicating no resistivity drift due to the structure relaxation of glass. In addition, the reset energy consumption of GeTe/Sb2Te3 interfacial phase change memory was reduced by more than 85% compared to conventional Ge2Sb2Te5 phase change memory at each bottom electrode contact size. Multi‐level‐cell operation mechanism and gradual increase in conductance value of GeTe/Sb2Te3 interfacial phase change memory was explained by a partial resistance transition model where phase transition occurred partially in all layers. The result of the GeTe/Sb2Te3 interfacial phase change memory performance is expected to bring great advantages to the next‐generation storage class memory industry that requires low energy and high density.
YY Hya and its interstellar environment
Authors: Kimeswenger Stefan , Thorstensen John R. , Fesen Robert A. , Drechsler Marcel , Strottner Xavier , Germiniani Maicon , Steindl Thomas , Przybilla Norbert , Weil Kathryn E. , Rupert Justin
Published: October 2021

Context. During a search for previously unknown Galactic emission nebulae, we discovered a faint 36′ diameter Hα emission nebula centered around the periodic variable YY Hya. Although this star has been classified as an RR-Lyr variable, such a classification is inconsistent with a Gaia distance of ≃450 pc. The GALEX image data also show YY Hya as having a strong UV excess, suggesting the existence of a hot and compact binary companion.

Aims. We aim to clarify the nature of YY Hya and its nebula.

Methods. In addition to our discovery image data, we obtained a 2.°5 × 2.°5 image mosaic of the whole region with CHILESCOPE facilities and time-series spectroscopy at MDM observatory. Also, we used data from various space missions to derive an exact orbital period and a spectral energy distribution.

Results. We find that YY Hya is a compact binary system containing a K dwarf star that is strongly irradiated by a hot white dwarf companion. The spectral characteristics of the emission lines that are visible only during the maximum light of the perfectly sinusoidal optical light curve show signatures resembling those of members of the BE UMa variable family. These are post-common-envelope pre-cataclysmic variables. However, the companion star here is more massive than that found in other group members and, thus, the progenitor of the white dwarf must have been a star between 3 and 4 M⊙. The nebula appears to be an ejected common-envelope shell with a mass on the order of one M⊙ and an age of 500 000 yr. This makes it the biggest such shell known thus far. The alignment of neighboring nebulosities some 45′ to the northeast and southwest of YY Hya suggests that the system has had strong bipolar outflows. We also briefly speculate that it might be related to the 1065 BP “guest-star” reported in ancient Chinese records.
Algorithms and radiation dynamics for the vicinity of black holes
Authors: Koutsantoniou Leela Elpida
Published: October 2021

We examine radiation and its effects on accretion disks orbiting astrophysical black holes. These disks are thermally radiating and can be geometrically and optically thin or thick. In this first paper of the series, we discuss the physics and the formulation required for this study. Subsequently, we construct and solve the relativistic radiative transfer equation, or find suitable solutions where that is not possible. We continue by presenting some of the accretion disks we considered for this work. We then describe the families of codes developed in order to study particle trajectories in strong gravity, calculate radiation forces exerted onto the disk material, and generate observation pictures of black hole systems at infinity. Furthermore, we also examine the veracity and accuracy of our work. Finally, we investigate how we can further use our results to estimate the black hole spin and the motion of disk material subjected to these radiation forces.
A first estimate of the Milky Way dark matter halo spin
Authors: Obreja Aura , Buck Tobias , Macciò Andrea V.
Published: October 2021

The spin, or normalized angular momentumλ, of dark matter halos in cosmological simulations follows a log normal distribution and has little correlation with galaxy observables such as stellar masses or sizes. There is currently no way to infer theλparameter of individual halos hosting observed galaxies. Here, we present a first attempt to measureλstarting from the dynamically distinct disks and stellar halos identified in high-resolution cosmological simulations with theGalactic Structure Finder (gsf). In a subsample of NIHAO galaxies analyzed withgsf, we find tight correlations between the total angular momentum of the dark matter halos,Jh, and the azimuthal angular momentum,Jz, of the dynamical distinct stellar components of the form: log(Jh) =α+β⋅log(Jz). The stellar halos have the tightest relation withα = 9.50 ± 0.42 andβ = 0.46 ± 0.04. The other tight relation is with the disks, for whichα = 6.15 ± 0.92 andβ = 0.68 ± 0.07. While the angular momentum is difficult to estimate for stellar halos, there are various studies that calculatedJzfor disks. In application to the observations, we usedGaiaDR2 and APOGEE data to generate a combined kinematics-abundance space, where the Galaxy’s thin and thick stellar disks stars can be neatly separated and their rotational velocity profiles,vϕ(R), can be computed. For both disks,vϕ(R) decreases with radius with ∼2 km s−1kpc−1forR ≳ 5 kpc, resulting in velocities ofvϕ,thin= 221.2 ± 0.8 km s−1andvϕ,thick= 188 ± 3.4 km s−1at the solar radius. We use our derivedvϕ,thin(R) andvϕ,thick(R) together with the mass model for the Galaxy of Cautun et al. (2020, MNRAS, 494, 4291) to compute the angular momentum for the two disks:Jz, thin = (3.26 ± 0.43)×1013andJz, thick = (1.20 ± 0.30)×1013 M⊙kpc km s−1, where the dark halo is assumed to follow a contracted NFW profile. Adopting the correlation found in simulations, the total angular momentum of the Galaxy’s dark halo is estimated to beJh= 2.69−0.32+0.371015 M⊙kpc km s−1and the spin estimate isλMW= 0.061−0.016+0.022, which translates into a probability of 21% using the universal log normal distribution function ofλ. If the Galaxy’s dark halo is assumed to follow a NFW profile instead, the spin becomesλMW= 0.088−0.020+0.024, making the Milky Way a more extreme outlier (with a probability of only 0.2%).
Simulations of the line-driven instability in magnetic hot star winds
Authors: Driessen F. A. , Kee N. D. , Sundqvist J. O.
Published: October 2021

Context. Line-driven winds of hot, luminous stars are intrinsically unstable due to the line-deshadowing instability (LDI). In non-magnetic hot stars, the LDI leads to the formation of an inhomogeneous wind consisting of small-scale, spatially separated clumps that can have great effects on observational diagnostics. However, for magnetic hot stars the LDI generated structures, wind dynamics, and effects on observational diagnostics have not been directly investigated so far.

Aims. We investigated the non-linear development of LDI generated structures and dynamics in a magnetic line-driven wind of a typical O-supergiant.

Methods. We employed two-dimensional axisymmetric magnetohydrodynamic simulations of the LDI using the Smooth Source Function approximation for evaluating the assumed one-dimensional line force. To facilitate the interpretation of these magnetic models, they were compared with a corresponding non-magnetic LDI simulation as well as a magnetic simulation neglecting the LDI.

Results. A central result obtained is that the wind morphology and wind clumping properties change strongly with increasing wind-magnetic confinement. Most notably, in magnetically confined flows, the LDI leads to large-scale, shellular sheets (‘pancakes’) that are quite distinct from the spatially separate, small-scale clumps in non-magnetic line-driven winds. We discuss the impact of these findings for observational diagnostic studies and stellar evolution models of magnetic hot stars.
The plight of female agricultural wageworkers in Morocco during the COVID-19 pandemic
Authors: Bossenbroek Lisa , Ftouhi Hind
Published: October 2021

While vaccination campaigns against COVID-19 were launched worldwide, a drama has been unfolding in the Moroccan countryside. It has been marked, over the last couple of decades, by rapid agrarian transformation, manifestations of which have included expanding irrigation frontiers and the increasing growth of high-value crops. These dynamics rely strongly on female agricultural wageworkers. Although they earn low wages, their income is crucial and is used to care for loved ones by paying for school fees, rent, electricity, and medicines. These workers, therefore, cannot afford to quit their jobs. However, most female wageworkers in Morocco are employed without a contract or social security cover. While working in an informal environment and living already in a precarious situation, little is known about how the pandemic has affected them. In this article, we seek to supply some of this information by drawing on the authors’ commitment over almost a decade of covering female wage-workers’ experiences in different agricultural regions in Morocco. Additionally, since March 2020, we have conducted 30 phone interviews with female laborers and farmers in the Saiss and in the coastal area of the Gharb and Loukkos. Using the pandemic as a focus, our results illustrate the inherent contradictions upon which Morocco’s agricultural boom has been founded. Although many female laborers are de facto heads of household or contribute in fundamental ways to the household income, they continue to be considered as secondary earners or as housewives, leading to low structural wages. Moreover, these women assume the prime responsibility for all domestic tasks, which are not economically recognized or valued. Consequently, they face new challenges in addition to their already precarious situations. Reduced work opportunities and limited state support have led to financial and psychological hardship which jeopardize their own and their family’s survival.
Experimental steam turbine T10MW cold end cooling by water spraying
Authors: Hoznedl Michal
Published: October 2021

The paper deals with steam flow in experimental turbine T10MW, located in Škoda laboratory. The flow was examined for low or negative outputs of the turbine, i.e. for the so called last stages ventilation. The flow path of the turbine was in the Boiler Feed Pump Turbine (BFPT) version. It had all together 4 stages out of which two were last stages with the outlet to the condenser. In the area of each of the two outlets cooling nozzles were located with water for cooling the outlet steam flow and the area of last blades root cross-sections. Cooling of these areas is necessary due to the compression heat that occurs in the off design (ventilation) regimes. Various proportional amounts of cooling water and flowing steam were tested experimentally in constant pressure behind both last stages. Due to the fact that the flow path and the exhaust hood were fitted with many static pressure taps, thermometers and with the possibility of probing the temperature field along the outlet cross-section height, a number of results were achieved. These were mainly the turbine outputs, steam flows through the blades and cooling nozzles, determination of saturation limits in individual places at the outlet as well as temperature differences measured by the probe and stable thermometers. It was found out that the amount of cooling water was oversized for blade roots cooling, while the flow at the tip was cooled only minimally. The results are beneficial both in terms of further research of steam turbines in low regimes because this is how most newly produced machines are operated and for the designers of these machines.
The effect of recuperator on the efficiency of ORC and TFC with very dry working fluid
Authors: Ahmed Aram Mohammed , Imre Attila R.
Published: October 2021

Organic Rankine Cycles (ORC) and Trilateral Flash Cycles (TFC) are very similar power cycles; ideally, they have a reversible adiabatic (isentropic) compression, an isobaric heating, an isentropic expansion and an isobaric cooling. The main difference is that for ORC, the heating includes the full evaporation of the working fluid (prior expansion); therefore, the expansion starts in a saturated or dry vapour state, while for TFC, the heating terminates upon reaching the saturated liquid states. Therefore, for TFT, expansion liquid/vapour state (in bubbly liquid or in vapour dispersed with droplets), requiring a special two-phase expander. Being ORC a more “complete” cycle, one would expect that its thermodynamic efficiency is always higher than for a TFC, between the same temperatures and using the same working fluids. Surprisingly, it was shown that for very dry working fluids, the efficiency of TFC can exceed the efficiency of basic (i.e. recuperator- and superheater-free) ORC, choosing sufficiently high (but still subcritical) maximal cycle temperature. Therefore in these cases, TFC (having a simpler heat exchange unit for heating) can be a better choice than ORC. The presence of a recuperator can influence the situation; by recovering the proper percentage of the remaining heat (after the expansion), the efficiency of ORC can reach and even pass the efficiency of TFC.
Validation of large eddy simulation of flow behind a circular cylinder
Authors: Isoz Martin , Hlavatý Tomáš , Uruba Václav , Procházka Pavel
Published: October 2021

The flow in the wake behind a circular cylinder in a cross-flow at Reynolds number of 4815 was studied both experimentally and via mathematical modeling. The mathematical model was performed as a Large Eddy Simulation (LES), while the experiments were carried out using the time-resolved variant of the Particle Image Velocimetry (PIV) method. Both the simulation and experiment took into account the dynamical aspects of the studied phenomenon, which enabled a detailed validation of the mathematical model. The overall statistical properties of the simulated flow were validated via comparing the time-averaged measured and computed velocity and vorticity fields. To validate the dynamical behavior, the velocity spectra were examined first. Next, the Proper Orthogonal Decomposition (POD) of the spatio-temporal velocity data was performed on both the experimental and numerical data and a comparison of the obtained energetic modes was carried out. All the performed validations have shown a satisfactory agreement between the simulation and the experiment.
Modelling fluid flow and heat transfer tasks for testing PIR motion Sensor
Authors: Kazda Jakub , Matas Richard , Sedláček Jan
Published: October 2021

The aim of this paper is to describe the methodology of modelling fluid flow and heat transfer tasks for testing electronic motion sensors, especially PIR (passive infra-red) motion sensors. The motion sensor measures changes in electromagnetic radiation in the infrared range caused by the movement of warmer objects compared to its surroundings. Distortion of the perception of the environment can lead to false alarms or insensitivity of the detector. PIR motion sensors should be designed and located to minimize heating of the lens by ambient air. The sensor may be exposed to conditions not specified in the basic standards. The practical part of this article deals with a non-standard test. A single-phase transient simulation in a specific test cabinet for two specific motion sensor models was performed using the computational fluid dynamics (CFD) method. The aim of these simulations was to evaluate the effect of hot flowing air on the lens and to compare the designs of both models. Comparison and analysis of the results showed that the test configuration does not guarantee a defined flow at the outlet of the pipeline, so a new configuration was designed.
Adaptable test rig for two-stage axial turbine
Authors: Němec Martin , Jelínek Tomáš
Published: October 2021

This contribution describes a new test rig for a two-stage axial turbine built in the VZLÚ. The test rig has replaced an original facility used for a full stage aerodynamics investigation. The motivation for the design of the new test facility was the limitations of the original one. The design is briefly discussed, and then the first measurement results are presented. The first operation was performed with a turbine stage already measured in the original facility. This allows the comparison of the most important quantities.