bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of observing response requirements to sample and comparison stimuli on the establishment of reject control (sample/S‐ relations)
Authors: Perez William F. , Huziwara Edson M. , Rodrigues Raone M. , Vilela Eduardo C. , Tomanari Gerson Y. , Vaidya Manish
Published: May 2020

The establishment of sample/S‐ relations (or reject control) during conditional discrimination training (AB, BC) affects transitivity (AC), equivalence (CA) and reflexivity (AA, BB, CC) test outcomes. The present study parametrically evaluated the effects of different observing patterns to comparison stimuli on the establishment of reject control during baseline conditional relation training. A matching‐to‐sample with observing requirements (MTS‐OR) procedure was implemented during AB and BC conditional discrimination training. During training, the participants were required to observe the sample and incorrect comparison on every trial before responding. In addition, the participants were divided into three groups that differed regarding the percentage of training trials on which they were prevented from observing the correct comparison stimuli: 25%, 50%, and 75%. Once the mastery criteria were achieved during training, transitivity (AC), symmetry (BA, CB), equivalence (CA), and reflexivity (AA, BB, CC) tests were conducted with all comparison stimuli visible from the beginning. The results suggest that the number of errors during transitivity, equivalence, and reflexivity tests progressively increased as participants were prevented from observing the correct comparison on a greater number of trials during training. Symmetry test results, however, were not affected by the experimental manipulation. Moreover, the number of participants showing reject‐control patterns during tests slightly increased and the number of participants showing select‐control patterns decreased as a function of the number of trials on which the participants were prevented from observing the correct comparison. Thus, we suggest that observing patterns during training is a relevant variable that affects equivalence test outcomes.
Green synthesis and antifungal activities of novel 3‐(trifluoromethyl)‐4,5‐dihydro‐1H‐furo[2,3‐c]pyrazole derivatives
Authors: Tan Fangshun , Su Shennan , Liu Zhenzhong
Published: May 2020

Trifluoromethylated molecules, as well as pyrazol‐3‐one derivatives, are found in a wide range of biologically active compounds. An highly facile, green and mild access to substituted 3‐(trifluoromethyl)‐4,5‐dihydro‐1H‐furo[2,3‐c]pyrazole derivatives by the cascade [3 + 2] Michael/Alkylation of unsaturated pyrazolones with α‐bromomalonate has been developed. The reactions can be performed in a easily available and environmentally benign solvent, and the substituted 3‐(trifluoromethyl)‐4,5‐dihydro‐1H‐furo[2,3‐c]pyrazole derivatives can be obtained in good to excellent yields by a simple purification step. The antifungal activities of these functional pyrazole derivatives were also evaluated and they showed high antifungal activity against Alternaria solani.
Distal leg structures of the Aculeata (Hymenoptera): A comparative evolutionary study of Sceliphron (Sphecidae) and Formica (Formicidae)
Authors: Beutel Rolf Georg , Richter Adrian , Keller Roberto A. , Hita Garcia Francisco , Matsumura Yoko , Economo Evan P. , Gorb Stanislav N.
Published: May 2020

The distal parts of the legs of Sceliphron caementarium (Sphecidae) and Formica rufa (Formicidae) are documented and discussed with respect to phylogenetic and functional aspects. The prolegs of Hymenoptera offer an array of evolutionary novelties, mainly linked with two functional syndromes, walking efficiently on different substrates and cleaning the body surface. The protibial‐probasitarsomeral cleaning device is almost always well‐developed. A complex evolutionary innovation is a triple set of tarsal and pretarsal attachment devices, including tarsal plantulae, probasitarsomeral spatulate setae, and an arolium with an internal spring‐like arcus, a dorsal manubrium, and a ventral planta. The probasitarsal adhesive sole and a complex arolium are almost always preserved, whereas the plantulae are often missing. Sceliphron has retained most hymenopteran ground plan features of the legs, and also Formica, even though the adhesive apparatus of Formicidae shows some modifications, likely linked to ground‐oriented habits of most ants. Plantulae are always absent in extant ants, and the arolium is often reduced in size, and sometimes vestigial. The arolium contains resilin in both examined species. Additionally, resilin enriched regions are also present in the antenna cleaners of both species, although they differ in which of the involved structures is more flexible, the calcar in Sceliphron and the basitarsal comb in Formica. Functionally, the hymenopteran distal leg combines (a) interlocking mechanisms (claws, spine‐like setae) and (b) adhesion mechanisms (plantulae, arolium). On rough substrate, claws and spine‐like setae interlock with asperities and secure a firm grip, whereas the unfolding arolium generates adhesive contact on smooth surfaces. Differences of the folded arolium of Sceliphron and Formica probably correlate with differences in the mechanism of folding/unfolding.
Immobilization of β‐1,4‐xylanase isolated from Bacillus licheniformisS3
Authors: Irfan Muhammad , Kiran Jawairia , Ayubi Salahuddin , Ullah Ameen , Rana Qurrat Ul Ain , Khan Samiullah , Hasan Fariha , Badshah Malik , Shah Aamer A.
Published: May 2020

Industrial applications require enzymes to be highly stable and economically viable in terms of reusability. Enzyme immobilization is an exciting alternative to improve the stability of enzymatic processes. Immobilization of β‐1,4‐xylanase produced by Bacillus licheniformis S3 is performed by using two polymer supports (agar–agar and calcium alginate). The maximum enzyme immobilization yield was achieved at a concentration of 3% agar, whereas a combination of sodium alginate, 4%, and calcium chloride, 0.3 M, was used for the formation of immobilized beads. The immobilization process increased the optimum reaction time from 10 min to 35 and 40 min for agar and calcium alginate, respectively, and the incubation temperature increased from 55°C to 60°C for agar, but it remained unchanged for calcium alginate. The pH profile of free and immobilized xylanase was quite similar in both cases. Both the techniques altered the kinetic parameters of immobilized β‐1,4‐xylanase as compared with the free enzyme. The diffusion limit of high molecular weight xylan caused a decline in Vmax of the immobilized enzyme, whereas there was an increase in the Km value. However, calcium alginate‐immobilized enzyme displayed broad thermal stability as compared with agar–agar‐immobilized enzyme and retained 57.1% of its initial activity at 80°C up to 150 min. Biotechnological characterization showed that the reusability of enzymes was the most striking finding, particularly of immobilized xylanase using agar–agar as immobilization carrier, which after six cycles retained 23% activity.
Brakes to the diffusion of a two‐sided social innovation: A case study on microinvestors' perspectives
Authors: Ashta Arvind , Estapé‐Dubreuil Glòria , Hédou Jean‐Pierre , Bourcieu Stéphan
Published: May 2020

The diffusion of social innovation requires overcoming institutional resilience and ignorance of innovation. The forces of the marketing and development work of the organization managers may be unable to overcome the strength of the institutional framework. These institution brakes include soft norms such as values, ideology, and psychology, as well as hard norms such as regulations. Spurts in the diffusion of the innovation require exogenous crises to overcome the friction.
The risk‐seeking propensity of Indian entrepreneurs: A study using GEM data
Authors: Mor Surender , Madan Sonu , Chhikara Ritu
Published: May 2020

The risk‐seeking propensity of total early‐stage entrepreneurial activities paves the way for further business‐related activities as risk plunging attitude leads to the creation of innovative business models, whereas risk aversion hampers new explorations. Skill, operational social entrepreneurial activities, and family size are the crucial factors influencing the risk‐seeking abilities of the total early‐stage entrepreneurs in India. Entrepreneurs involved in operational social entrepreneurial activities are likely to be more risk plungers as compared to commercial entrepreneurs. The promotion of social entrepreneurship by incentivizing and equipping the youth with the requisite skills and knowledge is the need of the hour for raising the risk‐seeking propensity.
Banking service in Bangladesh: The impact of service marketing mix on purchase intention of university students
Authors: Hossain Afzal , Humayun K. Chowdhury Md. , Hasan Shahedul , Shamsuzzaman Md. , Fahim Ather Y. , Yusuf H. Khan Md
Published: May 2020

Banking plays a vital role in the financial life of an industry, and the significance of banks can be realized from the fact that they are measured as to be the life‐blood of the modern economy. The Banking industry is considered as the mirror of any country. Banks are especially crucial for developing economies like Bangladesh, which has 57 listed banks. Due to increased competition, banks are trying to grab a new and growing market segment like the students' segment. So, there is a gap to explore student's purchase intention toward banking service as the intention is one of the critical predictors of behavior. Banks utilize service marketing strategies, a key concept of service marketing, to retain existing customers, and attract new ones. Therefore, this paper addressed the impact of a service marketing mix on the purchase intention of banking service among university students in Dhaka city, the capital of Bangladesh. The results should enable marketers to detect the most critical and significant drivers affecting the purchase intention of university students. All the elements of the service marketing mix except place, promotion, and physical evidence were significantly related to purchasing intention. It has implications for bank service marketers regarding the practical design of mix strategy of service marketing for student segments.
Analysis of a spatial network from the perspective of actor‐network theory
Authors: Park Kyoungok , Park Sungwoo , Lee Timothy J.
Published: May 2020

This study aims to interpret the relationships among the various actors (human including residents, tourists, artists, and so on, and non‐human environments including blogs, topographical features, and destination images) at a tourist site, in which those actors come together. Using the perspectives of actor‐network theory, the research observes how networks surrounding destinations are formed and changed by human and non‐human actors. It was discovered that once a tourism‐industry‐directed network had been newly introduced, the actors actively participated in network activities to achieve continuing benefits greater than those that would have been possible without this network.
Continuous Laryngeal Adductor Reflex Versus Intermittent Nerve Monitoring in Neck Endocrine Surgery
Authors: Sinclair Catherine F. , Téllez Maria J. , Ulkatan Sedat
Published: May 2020

Objective

Intraoperative neuromonitoring (IONM) techniques aim to identify and potentially prevent nerve injury during surgeries. Prior studies into the efficacy of recurrent laryngeal nerve (RLN) IONM convey mixed results, with some claiming equivalence between IONM and no monitoring at all. The goal of the current study was to compare continuous RLN monitoring using the laryngeal adductor reflex (LAR) to intermittent RLN monitoring (intermittent IONM) to determine whether continuous monitoring reduces the incidence of intraoperative RLN injury during neck endocrine surgeries.

Methods

In this observational, historical case‐control study, a historical cohort of patients monitored with intermittent‐IONM (group 1, n = 130) were compared to prospectively collected data from consecutive nerves‐at‐risk monitored continuously with the LAR (LAR‐CIONM, group 2, n = 205), at a single center by a single surgeon. The test benefit ratio and relative risk reduction (RRR) for LAR‐CIONM over intermittent IONM were calculated.

Results

For group 1, nine nerves at risk exhibited intraoperative LOS with transient postoperative vocal fold (VF) hypomobility (n = 2) or immobility (VFI, n = 7). For group 2, two nerves at risk (0.98%) had sudden intraoperative LAR LOS following bipolar cautery, resulting in postoperative transient VFI (P = .004). In each group, there was one case of permanent postoperative VFI. The test benefit rate ratio for LAR‐CIONM demonstrated a dramatic effect at 5.23, with an RRR of 81.0%.

Conclusion

LAR‐CIONM significantly decreased rates of postoperative transient VF paralysis and paresis over intermittent IONM alone (P = .004). Surgeons should be aware of the benefits and limitations of intermittent IONM versus CIONM. Intermittent IONM, although useful in nerve mapping and intraoperative decision making, has minimal benefit for the prevention of nerve injury, whereas CIONM can potentially reduce nerve injury rates and improve patient outcomes.

Level of Evidence

3 Laryngoscope, 131:230–236, 2021
On Pólya–Szegö reverse of Schwarz's inequality
Authors: Otachel Zdzisław
Published: May 2020

We present some new results on the Cauchy–Schwarz inequality in inner product spaces, where four vectors are involved. This naturally extends Pólya–Szegö reverse of Schwarz's inequality onto complex inner product spaces. Applications to the famous Hadamard's inequality about determinants and the triangle inequality for norms are given.
Two‐Step Solvent‐Free Synthesis of Poly(hydroxybutyrate)‐Based Photocurable Resin with Potential Application in Stereolithography
Authors: Foli Giacomo , Degli Esposti Micaela , Morselli Davide , Fabbri Paola
Published: May 2020

A bio‐based polymeric ink for stereolithography developed through a two‐step solvent‐free process is herein proposed. Specifically, low‐molecular‐weight poly(hydroxybutyrate) (PHB)‐diol oligomers are prepared via molten transesterification of bacterial PHB with 1,4‐butanediol. Transesterification conditions such as diol concentration, catalyst amount, and reaction time are studied for optimizing the final oligomers’ molecular weight and structural features. In the second step, the oligomeric hydroxyl terminals are converted into methacrylate moieties through a solvent‐free end‐capping reaction and diluted in propylene carbonate in order to obtain a photo‐polymerizable ink with suitable viscosity. The ink is UV‐cured, and the obtained material properties are investigated by FT‐IR and differential scanning calorimetry measurements. The proposed method provides a valuable and environmentally friendly alternative to currently available synthetic routes, overcoming their typical disadvantages related to the used solvents and harsh conditions. Moreover, it opens up a sustainable route for converting polyesters into functionalized oligomeric derivatives, which can potentially find application in 3D printing of customized biomedical devices.
Direct Synthesis of Chain‐end‐functionalized Poly(3‐hexylthiophene) without Protecting Groups Using a Zincate Complex
Authors: Inagaki Shin , Yamamoto Takuya , Higashihara Tomoya
Published: May 2020

Chain‐end‐functionalized poly(3‐hexylthiophene)s (P3HTs) with benzyl alcohol (─PhCH2OH), phenol (─PhOH), and benzoic acid (─PhCOOH) groups are directly synthesized based on the Negishi catalyst‐transfer polycondensation method utilizing the zincate complex oftBu4ZnLi2. In this system, neither protection nor deprotection steps are required, and also providing a living polymerization system to control the molecular weight while maintaining a low molar mass dispersity (ÐM) of the obtained P3HT derivatives. Indeed, the chain‐end‐functionalized P3HTs can be synthesized along with controlled number‐average molecular weights (Mn= 5100–20 000), lowÐM(1.06–1.14), and high chain‐end functionality (Fn = 46–86%). The Fn values for the alcohol and phenol groups are found to be high (86% for ─PhCH2OH and 71% for ─PhOH based on1H NMR, respectively), as also confirmed by matrix‐assisted laser desorption/ionization time of flight mass spectroscopy. The easily synthesizable chain‐end‐functionalized P3HTs will be applicable for the facile synthesis of block and branched polymers containing P3HT as well as its related semiconducting polymer segments.
A very compact microstrip diplexer fabrication with superior performance for broadband wireless applications
Authors: Yahya Salah I. , Rezaei Abbas
Published: May 2020

This study presents a planar dual‐channel bandpass microstrip diplexer based on a novel structure. It has the very compact size of 0.0081 λ
g2 (95.7 mm2) fabricated on 0.787 mm dielectric substrate height. Due to the use of close microstrip sections, several coupling capacitors are created. These capacitors can increase the degree of freedom for controlling the diplexer performance while it is optimized easily. Accordingly, the designed diplexer has a high performance in terms of wide fractional bandwidths, attenuated harmonics, flat channels, high return losses and low insertion losses. The wide fractional bandwidths (FBWs%) of 34.3% at the first channel and 38.6% at the second channel make the proposed diplexer appropriate for the broadband applications. The resonance frequencies are located at f1 = 1.6 GHz for the L‐band and f2 = 3 GHz for WiMAX applications. The maximum harmonic level is less than −20 dB for the frequencies up to 6.5 GHz (4f1). The maximum group delays are <1.26 ns at the first passband and 0.56 ns at the second passband. The proposed diplexer is fabricated and measured for verification. The comparison shows that both measured and simulated results are in a reasonable agreement.
High‐resolution multiparametric MRI of contemporary and waterlogged archaeological wood
Authors: Capuani Silvia , Stagno Valeria , Missori Mauro , Sadori Laura , Longo Sveva
Published: May 2020

High‐resolution NMR images on three different present‐day wood samples and an archaeological wood specimen were presented and discussed. Although the spatial resolution is still low to perform dendrology for the exact identification of the wooden species, the T2‐spin‐density weighted images exhibit contrasts that are in excellent agreement with optical histological images. On the other hand, T2* and T1‐weighted images provide physiological information that is not obtainable by the usual light microscopic investigations. Moreover, the diffusion‐weighted images show the anisotropic behaviour of the water diffusion coefficient quantified along and perpendicularly to vascular bundles (vessels and tracheids), which can be related to the morphology and size of wooden microstructure. This work suggests that high‐resolution multiparametric MRI may be a useful tool to increase the information obtainable from the waterlogged archaeological wood remains in a completely non‐invasive and non‐destructive approach. Therefore, it would be desirable to further develop the hardware and functional characteristics of MRI scanners to improve their potential application in the field of wooden cultural heritage.
Bilanz Novartis
Authors: Bulmahn Maren
Published: May 2020

Der Schweizer Pharmakonzern Novartis hat im abgelaufenen Geschäftsjahr Umsatz und Gewinn gesteigert. In Deutschland entwickelt und produziert der Konzernteil Sandoz Generika und Biosimilars.
Mensch, Natur, Gesellschaft – Chemieunterricht in der Schweiz
Authors: Rubner Isabel , Baars Günter
Published: May 2020

Die naturwissenschaftliche Bildung ist in Deutschland nicht einheitlich, genauso wenig ist dies in der Schweiz der Fall. Dennoch ist der Blick über die Grenze am Beispiel Chemie inspirierend.
Chemie, Köln und Karneval
Authors: Breugst Martin , Bruns Jörn , Díaz Hernandez Dolores , Disch Sabrina , Klußmann Martin , Olthof Selina , Strub Erik
Published: May 2020

Zum achten Mal fand in diesem Jahr am Department Chemie der Universität Köln die Carnival Conference Session (CCS‐2020) statt, traditionell am Mittwoch vor Karneval. Das Konzept der CCS: Auf Einladung der Nachwuchsgruppen des Departments finden Vorträge statt, die die Breite des Faches Chemie widerspiegeln und sich an Arbeitsgruppen und Studierende richten. Die Vorträge werden von Nachwuchswissenschaftlern gehalten.
Zu wertvoll für Schnaps
Authors: Osterath Brigitte
Published: May 2020

In Zeiten einer Pandemie wie der jetzigen ist Alkohol ein kostbares Gut. Vor allem Krankenhäuser und Arztpraxen können nicht darauf verzichten, da sie ihn als Desinfektionsmittel nutzen. Doch die Vorräte sind begrenzt.
Little Pharma
Authors: Ehlers Eberhard , Offermanns Heribert
Published: May 2020

Im Kampf gegen die Covid‐19‐Pandemie sind Start‐ups und Stiftungen die Hoffnungsträger.
Assessment of cardiac function, blood flow and myocardial tissue relaxation parameters at 0.35 T
Authors: Varghese Juliet , Craft Jason , Crabtree Christopher D. , Liu Yingmin , Jin Ning , Chow Kelvin , Ahmad Rizwan , Simonetti Orlando P.
Published: May 2020

A low field strength (B0) system could increase cardiac MRI availability for patients otherwise contraindicated at higher field. Lower equipment costs could also broaden cardiac MR accessibility. The current study investigated the feasibility of cardiac function with steady‐state free precession and flow assessment with phase contrast (PC) cine images at 0.35 T, and evaluated differences in myocardial relaxation times using quantitative T1, T2 and T2* maps by comparison with 1.5 and 3 T results in a small cohort of six healthy volunteers. Signal‐to‐noise ratio (SNR) differences across systems were characterized with proton density‐weighted spin echo phantom data. SNR at 0.35 T was lower by factors of 5.5 and 15.0 compared with the 1.5 and 3 T systems used in this study. All cine images at 0.35 T scored 3 or greater on a five‐point image quality scale. Normalized blood‐myocardium contrast in cine images, left ventricular volumes (end diastolic volume, end systolic volume) and function (ejection fraction and stroke volume) measures at 0.35 T matched 1.5 and 3 T results. Phase‐to‐noise ratio in 0.35 T PC images (11.7 ± 1.9) was lower than 1.5 T (18.7 ± 5.2) and 3 T (44.9 ± 16.5). Peak velocity and stroke volume determined from PC images were similar across systems. Myocardial T1 increased (564 ± 13 ms at 0.35 T, 955 ± 19 ms at 1.5 T and 1200 ± 35 ms at 3 T) while T2 (59 ± 4 ms at 0.35 T, 49 ± 3 ms at 1.5 T and 40 ± 2 ms at 3 T) and T2* (42 ± 8 ms at 0.35 T, 33 ± 6 ms at 1.5 T and 24 ± 3 ms at 3 T) decreased with increasing B0. Despite SNR deficits, cardiovascular function, flow assessment and myocardial relaxation parameter mapping is feasible at 0.35 T using standard cardiovascular imaging sequences.
A new class of cells with embedded discontinuity for fracture analysis by the boundary element method
Authors: Mendonça Tiago S. , Peixoto Rodrigo G. , Ribeiro Gabriel O.
Published: May 2020

Material failure analysis are addressed by the continuum strong discontinuity approach within the implicit formulation of the boundary element method in this work. An automatic cell generation algorithm is used to track cracks during the loading processes in the nonlinear analysis. As a major novelty, a new class of cells with embedded discontinuity is developed in which nonuniform displacement jump components are considered. It is shown that this new approach eliminates the stress locking effect verified in propagation analyses using cells with embedded uniform discontinuous displacement field, since the relative rotational motion between the two portions of a cell can now be properly captured.
Ein einzelnes Atom als Quantensonde
Authors: Mayer Daniel , Schmidt Felix , Widera Artur
Published: May 2020

Sensoren und Speicher werden immer kleiner, doch wo liegt die Grenze dieser Miniaturisierung? Kann ein Sensor aus nur einem Atom funktionieren, und wie kann die Quantenmechanik die Eigenschaften eines solchen Einzelatomsensors verbessern? In unserer Arbeitsgruppe an der TU Kaiserslautern haben wir Einzelatom‐Quantensonden für ultrakalte Gase konstruiert und untersucht, welchen Mehrwert hier die Quantenmechanik beispielhaft für Temperaturmessungen bringt.
Große, windgetriebene Meeresströmungen verschieben sich polwärts
Authors: Lohmann Gerrit , Yang Hu
Published: May 2020

Die globale Erwärmung hat viele verschiedene Auswirkungen auf das Klima. Zu den bekanntesten Folgen gehören neben dem Temperaturanstieg das Abschmelzen der Gletscher und Eisschilde sowie der Anstieg des Meeresspiegels. Es gibt jedoch auch weitere Veränderungen, die im Gange sind und nicht viel Aufmerksamkeit erhalten. Unsere Gruppe vom Alfred‐Wegener‐Institut hat kürzlich festgestellt, dass die großen Ozeanwirbel in einem sich erwärmenden Klima in höhere Breitengrade wandern [1].
Factors influencing performances and indicating risk of falls using the true Timed Up and Go test time of patients with hip fracture upon acute hospital discharge
Authors: Kristensen Morten T.
Published: May 2020

Objective

To examine the influence and risk of falls of individual factors on timed up and go test (TUG) times using standardized instructions in patients with hip fracture upon discharge from an acute orthopaedic hip fracture unit.

Methods

Following instructions, the TUG was performed three times with a rollator (standardized aid), as fast as safely possible. Up to a 1‐min rest was given after the first and second TUG trial. Multivariable linear regression analysis was used to investigate the factors influencing TUG‐times and corresponding logistic analysis was used to investigate factors indicating risk of falls, using a cut‐off of 24 s for TUG.

Results

A total of 181 patients (122 women), 60 years or older, with a mean (SD) age of 78.1 (9.1) years were studied. The fastest of three TUG trials performed within a mean of 10.0 (5.2) post‐surgery days and used in analyses reached a mean of 25.6 (11.0) s. Multivariable regression analysis showed that greater age (B = 0.24; 2.4s more per decade older), a low pre‐fracture function level (New Mobility Score <7 points, B = 6.4s more than high level), having a trochanteric fracture (B = 6.2 s, vs. cervical), and the post‐surgery day of testing (B = 0.42, 4.2s per 10 days later) were independently associated with using more time for performing the TUG. Correspondingly, the same four factors indicated an increased risk of falls in the logistic analysis. The linear model explained 28% of the variance on TUG, while the accuracy of the logistic model to predict patients having TUG≥24 s was 69%.

Conclusion

The age, pre‐fracture function, fracture type and post‐surgery day of TUG testing were identified as strong factors influencing TUG performances and TUG‐times indicating risk of falls in patients with hip fracture. We suggest that these factors be considered when interpreting TUG test results and in further rehabilitation and fall prevention efforts.
Fully Integrated Organic Field‐Effect Transistor Platform to Detect and to Quantify NO2 Gas
Authors: Yuvaraja Saravanan , Surya Sandeep G. , Vijjapu Mani Teja , Chernikova Valeriya , Shekhah Osama , Eddaoudi Mohamed , Salama Khaled Nabil
Published: May 2020

Herein, the gas sensing characteristics of PDVT‐10 organic field‐effect transistor (OFET) devices are explored and integrated to build a compact analog‐to‐digital converter (ADC) gas detection system. The electrical characteristics of the pristine PDVT‐10 OFET exhibit Ion/Ioff ratio and threshold voltage as 104 and −12 V, respectively. Through the coating of a metal‐organic framework (MOF) on the surface of PDVT‐10, the Ion/Ioff improves by one order of magnitude accompanied by significant positive threshold shift measured around 4 V. MOF is added as a pre‐concentrating material, and the device exhibits excellent selectivity and good sensitivity toward the target NO2 gas. Most of the reports available in the literature generally focus on the gas sensing performance of individual sensors, which does not have the potential to solve real‐time sensing problems. Hence, for the first time, a fully integrated ADC system is designed with just two OFETs. The integrated ADC system not only detects the NO2 gas with high sensitivity and selectivity but also generates a 5 bit digital output corresponding to different NO2 gas concentrations from 25 ppb to 1 ppm.
Implementing the HYbrid MAss flux Convection Scheme (HYMACS) in ICON – First idealized tests and adaptions to the dynamical core for local mass sources
Authors: Langguth M. , Kuell V. , Bott A.
Published: May 2020

In this study, the Hybrid MAss flux Convection Scheme (HYMACS) is implemented in the ICOsahedral Non‐hydrostatic (ICON) weather prediction model. In contrast to conventional convection parametrization schemes, the convective up‐ and downdraughts are solely treated as subgrid‐scale processes in HYMACS, whereas the environmental subsidence is passed to the grid‐scale dynamics of the hosting model. It is shown that the operational anisotropic divergence damping in ICON distorts the grid‐scale dynamical response on the net mass transport parametrized by HYMACS. Thus, a revised numerical filter configuration is developed which focuses on both the compatibility to local mass sources (sinks) and the effective suppression of numerical modes inherent from the model's triangular grid. Evaluation of Jablonowski–Williamson dynamical core experiments reveal that the combination of an isotropic second‐order divergence damping with a modified version of the fourth‐order divergence damping outperforms against numerical filters based on diffusion. The obtained results are similar to the operational set‐up indicating just a minor effect on the properties of the dynamical core. Moreover, a series of dry mass lifting experiments with the revised numerical filter confirms its compatability with HYMACS. The distortion of the grid‐scale circulation is removed while gravity waves are still retained despite the potentially degenerative effect of the fourth‐order divergence damping. Analyses of kinetic energy spectra confirm the effective suppression of checkerboard noise for a wide range of different situations. The present study may be understood as a base for future applications of HYMACS with a full cloud model in real‐case studies.
Toward the design of efficient adsorbents for Hg2+ removal: Molecular and thermodynamic insights
Authors: Forgionny Angélica , Acelas Nancy Y. , Jimenez‐Orozco Carlos , Flórez Elizabeth
Published: May 2020

A systematic DFT study was performed to evaluate the effect of oxygenated functional groups for Hg2+ adsorption in aqueous systems. This work includes several aspects usually neglected in many current works, namely, ground‐state multiplicity, solvation effects, establishment of thermodynamic parameters, atomic charge transfer, and modeling of infrared spectra. In addition, two carbonaceous models were studied to account for both the effect of the carbonaceous matrix and the oxygenated functional groups on the Hg2+ binding. Adsorption energies indicated that Hg2+ adsorption on the unsaturated model is favored in the following order: phenol > lactone > semiquinone > carboxyl, whereas for the saturated model, the Hg2+ adsorption energy decrease order is: carboxyl > semiquinone > lactone. Thermodynamic parameters confirmed that the adsorption process is spontaneous (unsaturated model), while the infrared spectra provided an insight at the atomic level about the experimentally reported bands. Our results contributed to a deeper understanding of the current experimental information on the effect of the surface functional groups on the Hg2+ adsorption over carbonaceous materials as different active sites can be present on oxygenated carbonaceous materials for metal adsorption. The results also create new ways to improve the performance of adsorption capability of mercury and other pollutants.
Photoelectron spectroscopy of electronic surface structure of the Cs/GaN and Cs/InN interfaces
Authors: Timoshnev Sergei , Benemanskaya Galina , Iluridze Georgi , Minashvili Tamaz
Published: May 2020

The electronic structure of the epitaxial GaN, InN nanolayers, and the ultrathin Cs/GaN and Cs/InN interfaces was investigated under ultrahigh vacuum at various Cs coverages. The experiment was carried out using synchrotron‐based photoelectron spectroscopy. The photoemission spectra of the valence band and the In 4d, N 2s, Ga 3d, and Cs 4d semicore levels were studied as a function of Cs coverages. It was found that the Cs adsorption in the submonolayer coverage region causes substantial changes in the spectra due to charge transfer between the Cs adlayer and surface Ga or In atoms. The strong interaction of the dangling bonds of Ga or In with Cs adatoms effectively increases the Ga or In valency.
Thermal Decomposition Behavior and Thermal Hazard of Benzoyl Peroxide under Different Environmental Conditions
Authors: Tan Yingxin , Xu Yabei , Shang Yiping , Wang Huayu , Li Wenjuan , Cao Weiguo
Published: May 2020

Thermal decomposition characteristics of benzoyl peroxide (BPO) were preliminary studied by differential scanning calorimetry (DSC), microcalorimeter (C600) and high‐pressure calorimeter (DSC 204 HP). DSC and C600 were used to research the effect of thermal history on the thermal decomposition characteristics of BPO. The time to maximum rate under adiabatic conditions (TMRad) and the self‐accelerating decomposition temperature (SADT) were calculated by combining with the thermal equilibrium equation. The results reveal that the initial decomposition temperature, the highest decomposition temperature and the decomposition completion temperature of BPO increased with the increase of heating rate. The mass scale and thermal history have significant effects on its thermal decomposition. The apparent activation energy of the BPO was calculated by the Kissinger method to be 146.8 kJ mol−1, the apparent activation energy calculated by Friedman method presents that BPO has different apparent activation energy at different stages of the reaction. TD2, TD4, TD8 and TD24 were gained to be 83.5, 80.2, 77.0 and 72.2 °C, respectively. With the increase of the packing quality, the SADT gradually decreased, resulting in a further increased in the risk. To prevent accidents, the initial temperature of BPO should be well governed and massive storage should be avoided.
Exceptional Antioxidant, Non‐Cytotoxic Activity of Integral Lemon Pectin from Hydrodynamic Cavitation
Authors: Nuzzo Domenico , Cristaldi Laura , Sciortino Marzia , Albanese Lorenzo , Scurria Antonino , Zabini Federica , Lino Claudia , Pagliaro Mario , Meneguzzo Francesco , Di Carlo Marta , Ciriminna Rosaria
Published: May 2020

Lemon pectin extracted along with water‐soluble flavonoids and other phytochemicals from citrus industry's waste lemon peel via hydrodynamic cavitation in water, directly at pre‐industrial scale and further isolated via freeze drying, shows exceptionally high antioxidant and non‐cytotoxic activity. Preliminary investigation indicates also significant antimicrobial activity. These findings open the route to the development of new nutraceutical and healthcare applications of a versatile biopolymer endowed with new functionality, rapidly and conveniently obtained from an abundant by‐product of the agri‐food industry.
Easy Fabrication of Bovine Serum Albumin/Astragalus Membranaceus Oil Microcapsules through a Sonochemical Method
Authors: Wang Xin , Guo Sheng‐Wei , Zhou Yi , Shen Hong‐Fang , Wang Liang , Wang Gu‐Xia
Published: May 2020

In the research, bovine serum albumin/astragalus membranaceus oil (BSA/AM) core‐shell microcapsules were prepared using the sonochemical method. The energy provided by ultrasound was used to initiate the cross‐linking reaction of the sulfhydryl groups of cysteine residue in BSA to form a disulfide bond, thereby encapsulating the core material‐AM. The core‐shell structure and morphology of the BSA/AM microcapsules were confirmed by transmission electron microscopy (TEM) and scanning electron microscopy (SEM), respectively. The microcapsule size was determined by dynamic light scattering (DLS). The composition and loading rate of AM were characterized through Fourier transform infrared spectroscopy (FT‐IR) and thermogravimetric analysis (TGA). The hardness and Young's modulus were measured using nanoindentation. And the release performance of BSA/AM microcapsules was investigated by ultraviolet‐visible spectrophotometer (UV‐Vis). The TEM and SEM results show that the BSA/AM microcapsules are spherical with a narrow size distribution. A core‐shell structure and a smooth microcapsule surface were clearly observed. The DLS results show that the microcapsules size and shell thickness are ca. 300 nm and 40 nm, respectively. The FT‐IR results indicate that the shell was formed by denaturing the cross‐linking of BSA under ultrasonic irradiation conditions. The loading rate of AM, approximately 67.6 %, was calculated by TGA. Based on nanoindentation, the hardness and Young's modulus are 0.0107 GPa and 0.1477 GPa, respectively. In terms of the release performance, all astragalus membranaceus oil can be almost released during the time period of four hours.
Selective Dosimetric Sensing of Hg2+ Ions by Design‐Based Small Molecular Gelator
Authors: Ghosh Sumit , Panja Atanu , Ghosh Kumaresh
Published: May 2020

Tripodal‐shaped trisaldehydes 1–3 have been designed and synthesized. Of the three trisaldehydes, compound 1 forms gel from DMF‐H2O (1 : 1, v/v) and DMSO‐H2O (1 : 1, v/v). The morphology of the gels is fibrous. Rheological studies reveal that DMF‐H2O gel shows high crossover point than DMSO‐H2O gel indicating its higher strain withstanding capability. Thiol protected compound 4, derived from compound 1, acts as progelator showing non gelation behavior under identical conditions. Specific Hg2+‐induced deprotection of thioacetal in compound 4 results in the formation of precursor aldehyde 1 and encourages sol‐to‐gel conversion in DMF‐H2O (1 : 1, v/v). The Hg2+‐induced gelation involves the dosimetric sensing as established by different spectroscopic techniques. The design of metal‐responsive low molecular weight gelators (LMWGs) involving protection/deprotection of functional groups in gelator's structure is rarely explored in the literature and thus present demonstration attracts attention.
First‐Principles Simulation of Highly Reactive Systems: Immediacy on a Femtosecond Time Scale
Authors: Frank Irmgard , Siekmann Dirk
Published: May 2020

Using Car‐Parrinello molecular dynamics we study the first reaction steps of the decomposition of a nitrogen‐rich molecule and of a mixture of molecular oxygen and molecular hydrogen. Using the simulated‐annealing approach we increase the temperature of the systems till they start to react. Both systems have in common that they react violently and that the precise reaction pathways, respectively the single reaction steps under the chosen conditions are largely unknown. While the first system decomposes completely within some hundred femtoseconds, the latter mixture reacts only partially on this timescale due to entropy. Complex reaction chains involving up to ten hydrogen and oxygen molecules allow for a fast reaction, but require a very specific arrangement. To our knowledge such reaction chains of neutral, stable, ground state molecules were not described before. The hope for a decomposition to nitrogen respectively to water is essentially fulfilled, but side products are observed.
Active Particle Based Selective Transport and Release of Cell Organelles and Mechanical Probing of a Single Nucleus
Authors: Wu Yue , Fu Afu , Yossifon Gilad
Published: May 2020

Self‐propelling micromotors are emerging as a promising microscale tool for single‐cell analysis. The authors have recently shown that the field gradients necessary to manipulate matter via dielectrophoresis can be induced at the surface of a polarizable active (“self‐propelling”) metallo‐dielectric Janus particle (JP) under an externally applied electric field, acting essentially as a mobile floating microelectrode. Here, the application of the mobile floating microelectrode to trap and transport cell organelles in a selective and releasable manner is successfully extended. This selectivity is driven by the different dielectrophoretic (DEP) potential wells on the JP surface that is controlled by the frequency of the electric field, along with the hydrodynamic shearing and size of the trapped organelles. Such selective and directed loading enables purification of targeted organelles of interest from a mixed biological sample while their dynamic release enables their harvesting for further analysis such as gene/RNA sequencing or proteomics. Moreover, the electro‐deformation of the trapped nucleus is shown to be in correlation with the DEP force and hence, can act as a promising label‐free biomechanical marker. Hence, the active carrier constitutes an important and novel ex vivo platform for manipulation and mechanical probing of subcellular components of potential for single cell analysis.
A Murine Oral‐Exposure Model for Nano‐ and Micro‐Particulates: Demonstrating Human Relevance with Food‐Grade Titanium Dioxide
Authors: Riedle Sebastian , Wills John W. , Miniter Michelle , Otter Don E. , Singh Harjinder , Brown Andy P. , Micklethwaite Stuart , Rees Paul , Jugdaohsingh Ravin , Roy Nicole C. , Hewitt Rachel E. , Powell Jonathan J.
Published: May 2020

Human exposure to persistent, nonbiological nanoparticles and microparticles via the oral route is continuous and large scale (1012–1013 particles per day per adult in Europe). Whether this matters or not is unknown but confirmed health risks with airborne particle exposure warns against complacency. Murine models of oral exposure will help to identify risk but, to date, lack validation or relevance to humans. This work addresses that gap. It reports i) on a murine diet, modified with differing concentrations of the common dietary particle, food grade titanium dioxide (fgTiO2), an additive of polydisperse form that contains micro‐ and nano‐particles, ii) that these diets deliver particles to basal cells of intestinal lymphoid follicles, exactly as is reported as a “normal occurrence” in humans, iii) that confocal reflectance microscopy is the method of analytical choice to determine this, and iv) that food intake, weight gain, and Peyer's patch immune cell profiles, up to 18 weeks of feeding, do not differ between fgTiO2‐fed groups or controls. These findings afford a human‐relevant and validated oral dosing protocol for fgTiO2 risk assessment as well as provide a generalized platform for application to oral exposure studies with nano‐ and micro‐particles.
Addressing Nanomaterial Immunosafety by Evaluating Innate Immunity across Living Species
Authors: Boraschi Diana , Alijagic Andi , Auguste Manon , Barbero Francesco , Ferrari Eleonora , Hernadi Szabolcs , Mayall Craig , Michelini Sara , Navarro Pacheco Natividad I. , Prinelli Alessandra , Swart Elmer , Swartzwelter Benjamin J. , Bastús Neus G. , Canesi Laura , Drobne Damjana , Duschl Albert , Ewart Marie‐Ann , Horejs‐Hoeck Jutta , Italiani Paola , Kemmerling Birgit , Kille Peter , Prochazkova Petra , Puntes Victor F. , Spurgeon David J. , Svendsen Claus , Wilde Colin J. , Pinsino Annalisa
Published: May 2020

The interaction of a living organism with external foreign agents is a central issue for its survival and adaptation to the environment. Nanosafety should be considered within this perspective, and it should be examined that how different organisms interact with engineered nanomaterials (NM) by either mounting a defensive response or by physiologically adapting to them. Herein, the interaction of NM with one of the major biological systems deputed to recognition of and response to foreign challenges, i.e., the immune system, is specifically addressed. The main focus is innate immunity, the only type of immunity in plants, invertebrates, and lower vertebrates, and that coexists with adaptive immunity in higher vertebrates. Because of their presence in the majority of eukaryotic living organisms, innate immune responses can be viewed in a comparative context. In the majority of cases, the interaction of NM with living organisms results in innate immune reactions that eliminate the possible danger with mechanisms that do not lead to damage. While in some cases such interaction may lead to pathological consequences, in some other cases beneficial effects can be identified.
Role of Redox‐Inactive Transition‐Metals in the Behavior of Cation‐Disordered Rocksalt Cathodes
Authors: Chen Dongchang , Wu Jinpeng , Papp Joseph K. , McCloskey Bryan D. , Yang Wanli , Chen Guoying
Published: May 2020

Owing to the capacity boost from oxygen redox activities, Li‐rich cation‐disordered rocksalts (LRCDRS) represent a new class of promising high‐energy Li‐ion battery cathode materials. Redox‐inactive transition‐metal (TM) cations, typically d0 TM, are essential in the formation of rocksalt phases, however, their role in electrochemical performance and cathode stability is largely unknown. In the present study, the effect of two d0 TM (Nb5+ and Ti4+) is systematically compared on the redox chemistry of Mn‐based model LRCDRS cathodes, namely Li1.3Nb0.3Mn0.4O2 (LNMO), Li1.25Nb0.15Ti0.2Mn0.4O2 (LNTMO), and Li1.2Ti0.4Mn0.4O2 (LTMO). Although electrochemically inactive, d0 TM serves as a modulator for oxygen redox, with Nb5+ significantly enhancing initial charge storage contribution from oxygen redox. Further studies using differential electrochemical mass spectroscopy and resonant inelastic X‐ray scattering reveal that Ti4+ is better in stabilizing the oxidized oxygen anions (On−, 0 < n < 2), leading to a more reversible O redox process with less oxygen gas release. As a result, much improved chemical, structural and cycling stabilities are achieved on LTMO. Detailed evaluation on the effect of d0 TM on degradation mechanism further suggests that proper design of redox‐inactive TM cations provides an important avenue to balanced capacity and stability in this newer class of cathode materials.
Separation of perfluoroalkyl substances by using nonaqueous capillary electrophoresis with conductivity detection
Authors: Lees Heidi , Jõul Piia , Siilak Kristjan , Vaher Merike
Published: May 2020

Perfluoroalkyl substances are chemical pollutants whose levels in the environment should be monitored. This work implemented nonaqueous capillary electrophoresis with conductivity detection to achieve separation of perfluoroheptanoic acid, perfluorooctanoic acid, and perfluorooctanesulfonate within 5 min. The mixture of 3‐(N‐morpholino)propanesulfonic acid and triethylamine in acetonitrile/methanol (50:50, v/v) was used as a background electrolyte. The method was linear (coefficients of determination ˃ 0.996) at analyte concentrations ranging from 2 to 20 μM with instrument detection limits varying between 0.30 and 0.75 μM depending on the analyte. The developed method was precise, the relative standard deviation of repeatability (n = 6) and reproducibility (n = 5) were less than 5.8% for the analytes used. The method was applied to the analysis of perfluoroheptanoic acid, perfluorooctanoic acid, and perfluorooctanesulfonate in wastewater samples treated by solid‐phase extraction, which further made it possible to achieve the method detection limits of perfluoroalkyl substances as low as 0.1–0.4 nM. Additionally, the applicability of the novel carbon aerogel‐based solid‐phase extraction and magnetic solid‐phase extraction were tested for the extraction of target compounds. It would be possible to transform the developed method into a portable format for on‐site analysis.
Lightning occurrence characteristics around tokyo skytree
Authors: Shindo Takatoshi , Miki Toru , Saito Mikihisa , Matsui Michihiro
Published: May 2020

The lightning occurrence characteristics around Tokyo Skytree are investigated with Japan Lightning Detection Network, and the results are evaluated with observation data by the Rogowski coils installed at a height of 497 m and by cameras set around Tokyo Skytree. After the construction of Tokyo Skytree, the apparent density of detected strokes near Tokyo Skytree increases, but without lightning strokes to Tokyo Skytree, the density of detected strokes around Tokyo Skytree seems to be roughly constant. © 2020 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.