bluuebunny/crossref_metadata_2025 huggingface dataset:
High frequency percussive ventilation in pediatric acute respiratory failure
Authors: Butler Andrew D. , Dominick Cheryl L. , Yehya Nadir
Published: December 2020

Objective

High frequency percussive ventilation (HFPV) is used in acute respiratory failure, but is poorly described in pediatrics. We aimed to describe the clinical characteristics, ventilator settings, and outcomes of a large pediatric cohort, and to determine predictors of who would benefit from HFPV.

Hypothesis

Gas exchange 2 h after HFPV initiation predicts success.

Design

Single center retrospective cohort study testing association between gas exchange 2 h after HFPV initiation with success, defined a priori.

Patients

Intubated children on HFPV for ≥2 h from 2012 to 2018.

Methods

We described indications, ventilator settings, and gas exchange immediately before, 2 h after, and at termination of HFPV. Univariate and multivariate regression tested association of oxygenation and ventilation after HFPV initiation with success. Areas under the receiver operating characteristic (AUROC) curve and adjusted odds ratios (aORs) were computed.

Results

We performed 237 courses of HFPV in 193 children (22% non‐survivors), of which 162 (68%) were successful. In univariate analysis, pH (AUROC, 0.65) and PCO2 (AUROC, 0.66) 2 h after HFPV predicted success. In multivariate analysis, pH (aOR: 1.67 per 1 SD; 95% confidence interval [CI]: 1.19–2.35), PCO2 (aOR: 0.49 per 1 SD; 95% CI: 0.31–0.79), and oxygenation index (aOR: 0.66 per 1 SD; 95% CI: 0.44–0.97) 2 h after HFPV initiation were associated with success.

Conclusion

We describe the largest cohort of HFPV to date, with detailed description of indications and settings. Gas exchange after 2 h of HFPV was independently associated with success.
On Some Unique Specificities of Ge‐Rich GeSbTe Phase‐Change Material Alloys for Nonvolatile Embedded‐Memory Applications
Authors: Luong Minh Anh , Agati Marta , Ratel Ramond Nicolas , Grisolia Jérémie , Le Friec Yannick , Benoit Daniel , Claverie Alain
Published: December 2020

Among the many possible phase‐change materials that can be used in digital memories, Ge‐rich GeSbTe (GGST) alloys are of special interest due to their much higher thermal stability, i.e., the higher crystallization temperature, they offer. However, in contrast to congruent materials which may transit from the amorphous to the crystalline state while keeping the same homogeneous chemical composition, GGST crystallization is obtained through the successive formation of the Ge and GST‐225 phases. For this reason, they show distinct properties and characteristics from those found in the canonical GST‐225 and GeTe alloys. Herein, some of these characteristics, their crystallization kinetics, the effect of N doping and oxidation, and their electrical properties are reviewed and highlighted.
Transient Optical Properties of CsPbX3/Poly(maleic anhydride‐alt‐1‐octadecene) Perovskite Quantum Dots for White Light‐Emitting Diodes
Authors: Xu Jian , Zhu Liang , Chen Jia , Riaz Saba , Sun Liwei , Wang Ying , Wang Wei , Dai Jun
Published: December 2020

Poly(maleic anhydride‐alt‐1‐octadecene) (PMAO)‐coated green CsPbBr3 and red CsPbBr0.6I2.4 quantum dots (QDs), as the phosphor materials for white light‐emitting diodes (WLEDs), are reported. The anhydride groups of PMAO can be bound to the surface ligands of perovskite QDs and act as a protective layer. The results show that CsPbX3/PMAO (X = Cl, Br, I) presents good crystallinity and excellent luminescence properties. Time‐resolved photoluminescence (TRPL) shows that the PL lifetime of CsPbX3/PMAO is prolonged, and the transient absorption (TA) results show that intraband hot‐exciton relaxation and exciton recombination can be slowed down when the CsPbX3 QDs are coated with PMAO. However, the PL quantum yields (PLQYs) increase for both the green‐emitting QDs and the red‐emitting QDs after PMAO coating. WLED devices are fabricated by integrating the green CsPbBr3/PMAO QDs and red CsPbBr0.6I2.4/PMAO QDs on the blue GaN chips. The devices show stable white light emission with Commission Internationale de L'Eclairage (CIE) color coordinates of (0.314, 0.291). The results indicate that CsPbX3/PMAO QDs can be an ideal downconversion fluorescent material for WLED devices.
What remains today of pre‐industrial Alpine rivers? Census of historical and current channel patterns in the Alps
Authors: Hohensinner Severin , Egger Gregory , Muhar Susanne , Vaudor Lise , Piégay Hervé
Published: December 2020

To date, no survey on the diverse channel patterns existing prior to the major phase of river regulation in the mid‐19th–early 20th century has been elaborated at the scale of the whole European Alps. The present paper fills this knowledge gap. The historical channel forms of the 143 largest Alpine rivers with catchments larger than 500 km2 (total length 11,870 km) were reconstructed based on maps dating from the 1750s to 1900. In the early 19th century, one‐third of the large Alpine rivers were multi‐channel rivers. Single‐bed channels oscillating between close valley sides were also frequent in the Alps (28%). Sinuous and even more so meandering channels were much rarer. Historical river patterns generally followed an upstream–downstream gradient according to slope condition, floodplain width and distance from the sources. The local occurrence of certain channel patterns, however, primarily reflected the tectonic/orographic conditions. Multi‐channel reaches were widespread within the whole Alpine area, alternating with confined and oscillating reaches. This demonstrates that most areas were mainly transport‐limited rather than supply limited. Sinuous and meandering reaches were more frequent in the north‐eastern Alps and were characterized by lower denudation rates and less sediment delivery.

Channel straightening caused the loss of about 510 km of river course length, equivalent to 4.3% of the historical extent. Multi‐channel stretches are currently a mere 15% of their historical length, and 45% of the larger Alpine rivers are intensively channelized or have been transformed into reservoirs. Channelization measures differed from one country to another. Human pressures directly affected both local channel geometry and the upstream controls (i.e., sediment supply). Accordingly, individual multi‐channel reaches also evolved into single‐thread channels without any local human interventions.
Cobalt‐Molybdenum Bimetal Phosphides Encapsulated in Carbon as Efficient and Durable Electrocatalyst for Hydrogen Evolution
Authors: Shi Jiazi , Hou Cunxia , Li Le , Xu Wencai , Fu Yabo , Huang Yanzhi , Xiong Ziyi , Cheng Weijia
Published: December 2020

Hydrogen evolution reaction (HER) from water electrolysis is an attractive technique developed in recent years for clean renewable energy. It is critical to develop a low‐cost, high activity and long‐time stability HER catalyst. In this work, a novel catalyst, Cobalt‐Molybdenum bimetal phosphides encapsulated in carbon matrix (Co‐Mo‐P@C), is synthesized using MOFs‐templated strategy by chemical vapor deposition (CVD) and phosphidation. The Co‐Mo‐P@C catalyst exhibits excellent catalytic performances with low overpotentials of 148 and 159 mV to reach current densities of 10 mA cm−2 for HER in both acidic and alkaline media, respectively, as well as long‐time durability over 20 h. This work introduces a new method for an efficient and stable HER catalyst and it may be extended to design other encapsulated bimetal nitrides, sulfides, and selenides for more applications.
Synthesis of Porous Mo2C/Nitrogen‐Doped Carbon Nanocomposites for Efficient Hydrogen Evolution Reaction
Authors: Li Siwei , Dong Baichuan , Yuanyuan  , Zhang  , Xu Ping
Published: December 2020

Transition metal carbides are considered to be promising non‐precious catalysts for electrochemical hydrogen evolution reaction (HER) because of their similar electronic structures to platinum‐based materials. In this work, we report the synthesis of porous nanocomposites consisting of β‐Mo2C nanoparticles supported on nitrogen‐doped carbon (NC) for efficient HER in both acidic and alkaline conditions. It is revealed that compared to the counterpart prepared through a one‐step annealing, the two‐step carbonization product (Mo2C/NC‐2) not only owns more catalytic active Mo2C sites on the surface, but also has electron interaction between Mo2C and NC. As a consequence, Mo2C/NC‐2 provides a geometric catalytic current density of −10 mA cm−2 at overpotentials of 169 mV and 180 mV vs. reversible hydrogen electrode (RHE) and Tafel slopes of 55 and 60 mV dec−1 in 0.5 M H2SO4 and 1 M KOH, respectively. This study provides valuable insights into the preparation of transition metal carbides with modulated surface structure and remarkable electrocatalytic activity for HER.
Design, Synthesis, In Silico Studies and In Vitro Anticancer Activity of 3‐(4‐Methoxyphenyl)azetidine Derivatives
Authors: Parmar Deepa R. , Rayani Rahul H. , Vala Anand G. , Kusurkar Rakesh V. , Manvar Roshani K. , Talukdar Sahista N. , Preeti  , Zunjar Vishwanath , Battula Satyanarayana , Soni Jigar Y.
Published: December 2020

A series of 3‐(4‐methoxyphenyl)azetidine analogues were synthesized and screened for their in vitro anticancer activity against nine different human cancer cell lines using the cell counting kit‐8 (CCK‐8) assay. The synthesized molecules were characterized by 1H NMR, 13C NMR, LCMS and IR analysis. The toxicity, bioavailability and lipophilicity of all the synthesized compounds were predicted by using osiris and molinspiration model. Molecular docking study revealed that, compound 6‐(3‐(3‐(2‐aminopyridin‐4‐yl)‐4‐methoxyphenyl)azetidin‐1‐yl)picolinonitrile (4 A‐17) and 6‐(3‐(4‐methoxy‐3‐(2‐methoxypyridin‐4‐yl)phenyl)azetidin‐1‐yl)picolinonitrile (4 A‐19) were found to be potential inhibitor of human topoisomerase IIα. The cell viability studies exhibited promising antiproliferative activities of the novel synthesized compounds. 4 A‐17 (EC50 0.03 μM) was found to be more potent than standard Doxorubicin (EC50 0.07 μM) in U251 cancer cell lines. Similarly, 4 A‐19 showed considerable potency against four different cancer cell lines (HepG2, U251, A431, 786‐O) with EC50 values ranging from 0.46 to 2.13 μM. These primary findings supported that molecule 4 A‐17 and 4 A‐19 should be subjected to further studies and lead optimization.
Synthesis of 2‐O‐Functionalized‐5‐salicyloyl Pyridine Derivatives Catalyzed by 2‐Mercaptobenzimidazole
Authors: Alizadeh Abdolali , Bagherinejad Akram
Published: December 2020

A concise and efficient one‐pot sequential approach for the synthesis of 5‐salicyloyl pyridine frameworks was developed from a reaction of 3‐formylchromones, malononitrile, various alcohols, and 2‐mercaptobenzimidazole as a catalyst. Malononitrile is the nitrogen source in this reaction. In this method, the variety of 2‐alkoxypyridines derivatives containing alkoxy, allyloxy, and acetylene functional groups can increase the bathochromic effect of the λmax of pyridine to the longer wavelengths. According to experimental and theoretical investigations by the DFT method, long‐wavelength bands of 5‐salicyloyl pyridine derivatives related to the HOMO→LUMO and HOMO→LUMO+1 transitions have the π→π* nature and are caused by intramolecular charge transfer from the phenol fragment to the pyridine ring.
Cu/Cu2O@g‐C3N4: Recyclable Photocatalyst under Visible Light to Access 2‐Aryl‐/benzimidazoles/benzothiazoles in Water
Authors: Singh Puneet K. , Bhardiya Smita R. , Asati Ambika , Rai Vijai K. , Singh Manorama , Rai Ankita
Published: December 2020

An unprecedented Cu/Cu2O@g‐C3N4 catalysed visible light driven green synthesis of 2‐aryl‐/benzimidazoles and benzothiazoles is reported via condensation of structurally different aldehydes with o‐phenylenediamine and o‐aminothiophenol respectively. Herein, Synergistic catalysis is operating as both Cu/Cu2O@g‐C3N4 and visible‐light condition are required, no product was isolated in absence of either. Operational simplicity, ambient reaction conditions, aqueous medium, good yield of products (80–94 %) and recyclability of the catalyst without any loss in catalytic efficiency and selectivity are salient features of the envisaged protocol.
Synthesis, Characterization and Investigation of Hydrogen Evolution Activity of Ni‐Mo/Al2O3 Composite
Authors: Salarvand V. , Mahmoodi H. , Ahmadian F. , Farahbakhsh N. , Yousefifar A. , Saghafi M. , Noghani M. T.
Published: December 2020

In the present study, the hydrogen evolution activity of the Ni−Mo/Al2O3 catalyst was investigated. This catalyst was produced by milling of oxide precursors of nickel oxide (NiO) and molybdenum trioxide (MoO3) with aluminum as a reducing agent. So that oxide precursors with 100 % excess aluminum on stoichiometric composition at different times were milled to perform complete reduction operations. Subsequently, X‐ray diffraction (XRD) analysis was performed for phase analysis and scanning electron microscopy (SEM) was used to investigate the microstructure. It was found that oxide precursors with 100 % excess aluminum on stoichiometric composition were reduced after 50 h of milling and nickel molybdenum/alumina composite was produced. On the other hand, to compare the activity of Ni−Mo/Al2O3 two different catalysts (57 NiMo, 80 NiMo) were also produced by the milling method. The specimens were transformed into pills of 10 mm in diameter and 3 mm in height at 900 MPa pressure. A furnace under an argon atmosphere at a temperature of 1400 °C was used to sinter the produced pills. Finally, the hydrogen evolution activity of this sample was investigated by linear polarization tests and impedance spectroscopy in 1 M KOH solution. The sample reduced with 100 % excess aluminum showed higher activity than the stoichiometric combination, with −62 mV cathodic‐Tafel slope, −70 mV over‐potential at a current density of −10 mA cm−2 and a charge transfer resistance of 126.6 ohms.
Ink‐Assisted Synthetic Strategy for Stable and Advanced Composite Electrocatalysts with Single Fe Sites
Authors: Zhang Zhengyuan , Hao Jinhui , Lu Yahui , Xu Yuqi , Li Longhua , Shi Weidong
Published: December 2020

The oxygen evolution reaction is critical to the efficiency of many energy technologies that store renewable electricity in chemical form. However, the rational design of high‐performance and stable catalysts to drive this reaction remains a formidable challenge. Here, a facile ink‐assisted strategy to construct a series of stable and advanced composite electrocatalysts with single Fe sites for permitting seriously improved performance characteristics is reported. As revealed by a suit of characterization techniques and theoretical methods, the improved electrocatalytic performance and stability can be attributed to the unique coordination states of Fe in the form of distorted FeO4C and the interfacial effect in the composite system that optimize and stabilize single Fe sites in changing to better configurations for intermediates adsorption. The findings provide a novel strategy to in‐depth understanding of practical guidelines for the electrocatalyst design for energy conversion devices.
Self‐Piercing Riveting of Hot Stamped Steel and Aluminum Alloy Sheets Base on Local Softening Zone
Authors: Zhang Yongqiang , Yi Rigui , Wang Pengbo , Fu Can , Cai Ning , Ju Jianbin
Published: December 2020

Self‐piercing riveting (SPR) has been used to joint steel to aluminum alloy sheets in multimaterial car body. It is a challenge to joint high strength steel to aluminum alloy by SPR process, especially for materials with high strength and large thickness. Herein, the SPR process for 1500 MPa hot stamped steel and aluminum alloy sheets is studied by experiment and simulation method. The laser heat treatment process is applied to the hot stamped steel sheet before joining. The relationship between heat treatment process and hardness distribution is studied and the softening zone with hardness less than 300 HV is obtained. Furthermore, the local softening zone is joined to an aluminum alloy sheet by SPR process. In the process, the rivets with high hardness are used to pierce the steel sheet. The failure mode and maximum tensile shear force of the joint are studied. At the same time, the joints without laser heat treatment are compared. The results show that the interlock and the maximum shear force for laser heat treatment increase by 91% and 26%, respectively.
Experimental study on seismic performance of steel fiber reinforced concrete wall piers
Authors: Babaei Ali , Mortezaei Alireza , Salehian Hamidreza
Published: December 2020

Extensive damage to the bridges in recent earthquakes has revealed the vulnerability of these structures to the seismic excitation. Bridge piers play a key role in maintaining the operability of the bridge structure during and after earthquakes. As determinant elements in single‐pier bridges, wall piers significantly affect the bridge structure behavior. Hence, the present experimental study was conducted to examine the seismic performance of wall piers made of modern materials, that is, fiber reinforced concrete (FRC) in RC bridges. Eight wall piers made of steel fiber reinforced concrete (SFRC) with different aspect ratios, steel percentages and concrete strength were subjected to lateral load. The results showed that using SFRC reduced the steel strain within the serviceability range. Compared to conventional concrete, SFRC changes failure modes and deformational characteristics and also increases the energy dissipation capacity, stiffness in every drift values, load‐bearing capacity as well as yielding length.
Anti‐inflammatory effect of fermented brown rice and rice bran with Aspergillus oryzae on mice
Authors: Umeyama Lin , Kasahara Shiori , Sugawara Misa , Yokoyama Satoru , Saiki Ikuo , Hayakawa Yoshihiro
Published: December 2020

Aim

In this study, we examined the anti‐inflammatory effect of fermented brown rice and rice bran with Aspergillus oryzae (FBRA) on acute and chronic inflammation mouse models.

Methods

As an acute inflammation model, we used a 12‐O‐tetradecanoylphorbol‐13‐acetate (TPA)‐induced ear edema model. As a chronic inflammation model, we used an imiquimod (IMQ)‐induced psoriasis model and ragweed pollen‐induced allergic rhinitis model. We also investigated the effect of FBRA on the expression of inflammatory mediators in skin biopsies from the imiquimod‐induced psoriasis model.

Results

The mice fed the 10% FBRA‐containing diet showed lower‐level inflammation among the three different experimental models. In the IMQ‐induced psoriasis model, mRNA expressions of IL‐17A, IL‐1β and COX‐2 were significantly inhibited in the skin tissue of mice fed 10% FBRA diet.

Conclusion

Our data suggest the potential benefit of FBRA as a functional food to prevent excessive inflammation.
The Critical Imperative: Evidence‐Based Practices to Strengthen Leadership Development
Authors: Dugan John P. , Randolph Patrick , Hightower Christian , Rossetti Ana M.
Published: December 2020

Using the Aspen Young Leaders Fellowship as a case study, the authors assert that leadership educators have a responsibility to apply critical perspectives to their work with evidence‐based practice, which involves interrogating assumptions as well as reconstructing pedagogical and design practices to increase equity in leadership education.
Effects of a Δ-9-fatty acid desaturase and a cyclopropane-fatty acid synthase from the novel psychrophile Pseudomonas sp. B14-6 on bacterial membrane properties
Authors: Choi Tae-Rim , Park Ye-Lim , Song Hun-Suk , Lee Sun Mi , Park Sol Lee , Lee Hye Soo , Kim Hyun-Joong , Bhatia Shashi Kant , Gurav Ranjit , Lee Yoo Kyung , Sung Changmin , Yang Yung-Hun
Published: December 2020

Psychrophilic bacteria, living at low and mild temperatures, can contribute significantly to our understanding of microbial responses to temperature, markedly occurring in the bacterial membrane. Here, a newly isolated strain, Pseudomonas sp. B14-6, was found to dynamically change its unsaturated fatty acid and cyclic fatty acid content depending on temperature which was revealed by phospholipid fatty acid (PLFA) analysis. Genome sequencing yielded the sequences of the genes Δ-9-fatty acid desaturase (desA) and cyclopropane-fatty acid-acyl-phospholipid synthase (cfa). Overexpression of desA in Escherichia coli led to an increase in the levels of unsaturated fatty acids, resulting in decreased membrane hydrophobicity and increased fluidity. Cfa proteins from different species were all found to promote bacterial growth, despite their sequence diversity. In conclusion, PLFA analysis and genome sequencing unraveled the temperature-related behavior of Pseudomonas sp. B14-6 and the functions of two membrane-related enzymes. Our results shed new light on temperature-dependent microbial behaviors and might allow to predict the consequences of global warming on microbial communities.
Higher-Order PLS-PM Approach for Different Types of Constructs
Authors: Crocetta Corrado , Antonucci Laura , Cataldo Rosanna , Galasso Roberto , Grassia Maria Gabriella , Lauro Carlo Natale , Marino Marina
Published: December 2020

Partial least squares path modeling (PLS-PM) has become very popular in recent years, for measuring concepts that depend on different aspects and that are based on different types of relationships. PLS-PM represents a useful tool to explore relationships and to analyze the influence of the different aspects on the complex phenomenon analyzed. In particular, the use of higher-order constructs has allowed researchers to extend the application of PLS-PM to more advanced and complex models. In this work, our attention is focused on higher-order constructs that include reflective or formative relationships. Even if the dispute between formative models and reflective models is not exactly recent, it is still alive in current literature, for the most part within the context of structural equation models. This paper focuses attention on theoretical and mathematical differences between formative and reflective measurement models within the context of the PLS-PM approach. A simulation study is proposed in order to show how these approaches fit well in different modeling situations. The approaches have been compared using empirical application in a sustainability context. The findings from the simulation and the empirical application can help researchers to estimate and to use the higher-order PLS-PM approach in reflective and formative type models.
Quasielastic Neutron Scattering and Molecular Dynamics Simulation Study on the Molecular Behaviour of Catechol in Zeolite Beta
Authors: Hernandez-Tamargo Carlos , Silverwood Ian P. , O’Malley Alexander J. , Leeuw Nora H. de
Published: December 2020

The dynamics of catechol in zeolite Beta was studied using quesielastic neutron scattering (QENS) experiments and molecular dynamics simulations at 393 K, to understand the behaviour of phenolic monomers relevant in the catalytic conversion of lignin via metal nanoparticles supported on zeolites. Compared to previous work studying phenol, both methods observe that the presence of the second OH group in catechol can hinder mobility significantly, as explained by stronger hydrogen-bonding interactions between catechol and the Brønsted sites of the zeolite. The instrumental timescale of the QENS experiment allows us to probe rotational motion, and the catechol motions are best fit to an isotropic rotation model with a $$D^{rot}$$

D

rot

of 2.9 × 10$$^{10}$$

10

s$$^{-1}$$

-
1

. While this $$D^{rot}$$

D

rot

is within error of that measured for phenol, the fraction of molecules immobile on the instrumental timescale is found to be significantly higher for catechol. The MD simulations also exhibit this increased in ‘immobility’, showing that the long-range translational diffusion coefficients of catechol are lower than phenol by a factor of 7 in acidic zeolite Beta, and a factor of $$\sim$$
∼
3 in the siliceous material, further illustrating the significance of Brønsted site H-bonding. Upon reproducing QENS observables from our simulations to probe rotational motions, a combination of two isotropic rotations was found to fit the MD-calculated EISF; one corresponds to the free rotation of catechol in the pore system of the zeolite, while the second rotation is used to approximate a restricted and rapid “rattling”, consistent with molecules anchored to the acid sites through their OH groups, the motion of which is too rapid to be observed by experiment.
A giant step forward: chimeric antigen receptor T-cell therapy for lymphoma
Authors: Zhao Houli , Wang Yiyun , Yin Elaine Tan Su , Zhao Kui , Hu Yongxian , Huang He
Published: December 2020

The combination of the immunotherapy (i.e., the use of monoclonal antibodies) and the conventional chemotherapy increases the long-term survival of patients with lymphoma. However, for patients with relapsed or treatment-resistant lymphoma, a novel treatment approach is urgently needed. Chimeric antigen receptor T (CAR-T) cells were introduced as a treatment for these patients. Based on recent clinical data, approximately 50% of patients with relapsed or refractory B-cell lymphoma achieved complete remission after receiving the CD19 CAR-T cell therapy. Moreover, clinical data revealed that some patients remained in remission for more than two years after the CAR-T cell therapy. Other than the CD19-targeted CAR-T, the novel target antigens, such as CD20, CD22, CD30, and CD37, which were greatly expressed on lymphoma cells, were studied under preclinical and clinical evaluations for use in the treatment of lymphoma. Nonetheless, the CAR-T therapy was usually associated with potentially lethal adverse effects, such as the cytokine release syndrome and the neurotoxicity. Therefore, optimizing the structure of CAR, creating new drugs, and combining CAR-T cell therapy with stem cell transplantation are potential solutions to increase the effectiveness of treatment and reduce the toxicity in patients with lymphoma after the CAR-T cell therapy.
Synthesis of highly active Cu(I)-Y(III)-Y zeolite and its selective adsorption desulfurization performance in presence of xylene isomers
Authors: Jiang Bo-Long , Jiang Nan , Chang You-Xin
Published: December 2020

A bimetal-exchanged NaY zeolite (Cu(I)-Y(III)-Y) with a desirable adsorptive desulfurization (ADS) performance was prepared and characterized by means of X-ray diffraction, specific surface area measurements, X-ray fluorescence spectrometer, X-ray photoelectron spectroscopy, thermal gravity analysis and Fourier transform infrared spectroscopy. The effect of Y(III) ions on ADS in the presence of the xylenes was investigated. Results indicated that the ADS performance of Y(III)-Y is higher than that of most reported CeY. The Y(III)-based Cu(I)-Y(III)-Y demonstrated the higher breakthrough loading than those of reported Ce(III)/Ce(IV)-based transition metal Y zeolites, showing that Y(III) ions play a promoting role in improving the ADS selectivity. For Cu(I)-Y(III)-Y, a new strong S-M interaction (S stands for sulfur, while M stands for metal) active site was formed, which might be caused by the synergistic effect between Cu(I) and Y(III). The Cu(I)-Y(III)-Y, which combined the advantages of Cu(I)-Y and Y(III)-Y, is a kind of promising adsorbent. The breakthrough loading decreased in the order of Cu(I)-Y(III)-Y > Y(III)-Y > Cu(I)-Y, and the effect of xylene isomers on the sulfur removal was in the order of ortho-xylene > meta-xylene > para-xylene, which exhibited the same trend with the bond order of xylenes.
Understanding Collaboration with Virtual Assistants – The Role of Social Identity and the Extended Self
Authors: Mirbabaie Milad , Stieglitz Stefan , Brünker Felix , Hofeditz Lennart , Ross Björn , Frick Nicholas R. J.
Published: December 2020

Organizations introduce virtual assistants (VAs) to support employees with work-related tasks. VAs can increase the success of teamwork and thus become an integral part of the daily work life. However, the effect of VAs on virtual teams remains unclear. While social identity theory describes the identification of employees with team members and the continued existence of a group identity, the concept of the extended self refers to the incorporation of possessions into one’s sense of self. This raises the question of which approach applies to VAs as teammates. The article extends the IS literature by examining the impact of VAs on individuals and teams and updates the knowledge on social identity and the extended self by deploying VAs in a collaborative setting. Using a laboratory experiment with N = 50, two groups were compared in solving a task, where one group was assisted by a VA, while the other was supported by a person. Results highlight that employees who identify VAs as part of their extended self are more likely to identify with team members and vice versa. The two aspects are thus combined into the proposed construct of virtually extended identification explaining the relationships of collaboration with VAs. This study contributes to the understanding on the influence of the extended self and social identity on collaboration with VAs. Practitioners are able to assess how VAs improve collaboration and teamwork in mixed teams in organizations.
Organisationsstruktur und Führungsstil nach Akquisitionen – eine empirische Untersuchung
Authors: Kretschmer Tobias , Dehne Christoph
Published: December 2020

Viele Akquisitionen bleiben hinter den in sie gesetzten Erwartungen zurück. Ein Grund hierfür kann sein, dass Synergien nur dann realisiert werden, wenn der Akquisition ein erfolgreicher Post-Merger-Integrationsprozess folgt, der häufig Veränderungen in der Organisationsstruktur und im Führungsstil impliziert. Anhand einer Stichprobe von 230 europäischen Unternehmen untersuchen wir die Tendenz der akquirierten Unternehmen, die Organisationsstruktur und den Führungsstil des akquirierenden Unternehmens zu übernehmen. Unsere Ergebnisse zeigen, dass Veränderungen hauptsächlich im akquirierten Unternehmen stattfinden und dass Veränderungen im Führungsstil oft durch Änderungen der Unternehmensstruktur bedingt werden.
Conditional stability of multi-solitons for the 1D NLKG equation with double power nonlinearity
Authors: Yuan Xu
Published: December 2020

We consider the one-dimensional nonlinear Klein–Gordon equation with a double power focusing-defocusing nonlinearity

\partial _{t}^{2}u−\partial _{x}^{2}u + u−|u|^{p−1}u + |u|^{q−1}u = 0, \quad \mathrm{on}\ [0,\infty) \times \mathbb{R},

where

1 < q < p < \infty

. The main result states the stability in the energy space

H^{1}(\mathbb{R}) \times L^{2}(\mathbb{R})

of the sums of decoupled solitary waves with different speeds, up to the natural instabilities. The proof is inspired by the techniques developed for the generalized Korteweg-de Vries equation and the nonlinear Schrödinger equation in a similar context by Martel, Merle and Tsai [14,15]. However, the adaptation of this strategy to a wave-type equation requires the introduction of a new energy functional adapted to the Lorentz transform.
Long time confinement of vorticity around a stable stationary point vortex in a bounded planar domain
Authors: Donati Martin , Iftimie Dragoș
Published: December 2020

In this paper we consider the incompressible Euler equation in a simply-connected bounded planar domain. We study the confinement of the vorticity around a stationary point vortex. We show that the power law confinement around the center of the unit disk obtained in [2] remains true in the case of a stationary point vortex in a simply-connected bounded domain. The domain and the stationary point vortex must satisfy a condition expressed in terms of the conformal mapping from the domain to the unit disk. Explicit examples are discussed at the end.
Editorial
Authors: Barrett Steve
Published: December 2020

Blue, grey, turquoise, yellow, or the more familiar green – there is an increasing spectrum available, so what colour is your hydrogen?
Developments in the global hydrogen market: The spectrum of hydrogen colours
Authors: Newborough Marcus , Cooley Graham
Published: December 2020

The fundamental reasons for considering the adoption of hydrogen as a fuel, industrial feedstock and energy storage medium are presented. Hydrogen production methods are outlined, with reference to the colour prefixes used to describe different types of hydrogen. The relative greenhouse gas emissions and economics of green and blue hydrogen production are considered for achieving a ‘net zero’ climate-neutral energy system by 2050. In general, it appears that green hydrogen will soon be cheaper than blue hydrogen due to the falling costs of renewable electricity and electrolysers, then cheaper than grey hydrogen, and in the long term potentially cheaper than natural gas.
Averting Expenditures and Willingness to Pay for Electricity Supply Reliability
Authors: Niroomand Naghmeh , Jenkins Glenn P.
Published: December 2020

Nepal has suffered from the worst electricity shortages in South Asia. This study is an attempt to measure the willingness to pay for an improved service using a model of revealed preference. Respondents are asked about the actions they are taking to reduce the impact on their household or business of scheduled and unscheduled outages and more stable voltage. We estimate the averting expenditures that were being incurred to compensate for the lack of reliability of the electricity service. The estimated cost of the averting actions as a percentage of the electricity bills is 53 % for households, 47 % for small businesses, 46 % for medium businesses, and 35 % for large businesses. Based on the estimations, we find that in 2017 the annual benefit from improving the reliability of the electricity service would be approximately US$ 188 million with a present value over 20 years of US$ 1.6 billion.
The effect of type of ventilation used in the operating room and surgical site infection: A meta-analysis
Authors: Bao Jian , Li Jianhua
Published: December 2020

Abstracts

Background:

The relation between type of ventilation used in the operating room and surgical site infection has drawn considerable attention with its conflicting results. A possible relationship between the type of ventilation used in the operating room and surgical site infection has been reported. This meta-analysis was performed to evaluate this relationship.

Methods:

A systematic literature search up to May 2020 identified 14 studies with 590,121 operations, 328,183 operations of which were performed under laminar airflow ventilation and 261,938 of which were performed operations under conventional ventilation. These articles reported relationships between type of operating-room ventilation with its different categories and surgical site infection: 10 studies were related to surgical site infection in the total hip replacement; 7 studies in total knee arthroplasties; and 3 studies in different abdominal and open vascular surgery. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated comparing surgical site infection prevalence and type of operating room ventilation using the dichotomous method with a random-effects or fixed-effects model.

Results:

No significant difference was found between operation performed under laminar airflow ventilation and conventional ventilation in total hip replacement (OR, 1.23; 95% CI, 0.97–1.56, P = .09), in total knee arthroplasties (OR, 1.14; 95% CI, 0.62–2.09; P = .67), and in different abdominal and open vascular surgery (OR, 0.75; 95% CI, 0.43-1.33; P = .33). The impact of the type of operating room ventilation may have no influence on surgical site infection as a tool for decreasing its occurrence.

Conclusions:

Based on this meta-analysis, operating under laminar airflow or conventional ventilation may have no independent relationship with the risk of surgical site infection. This relationship forces us not to recommend the use of laminar airflow ventilation because it has a much higher cost compared to conventional ventilation.
Rural Aboriginal high school students' views of their future tertiary education
Authors: Howard Jessica , Jeffery Jacob , Walters Lucie , Barton Elsa
Published: December 2020

Abstract In the context of a stark discrepancy in the educational outcomes of Aboriginal Australians compared to non-Aboriginal Australians, this article aims to contribute the voices of rural Aboriginal high school students to the discourse. This article utilises an appreciative enquiry approach to analyse the opinions and aspirations of 12 Aboriginal high school students in a South Australian regional centre. Drawing on student perspectives from semi-structured interviews, this article contributes to and contextualises the growing body of literature regarding educational aspirations. It demonstrates how rurality influences a complex system of intrinsic attributes, relationship networks and contextual factors. It offers an important counterpoint to discourses surrounding academic disadvantage and highlights the lived experience of rural Aboriginal Australians.
NOTES ON THE K-RATIONAL DISTANCE PROBLEM
Authors: THO NGUYEN XUAN
Published: December 2020

Let K be an algebraic number field. We investigate the K-rational distance problem and prove that there are infinitely many nonisomorphic cubic number fields and a number field of degree n for every

$n\geq 2$
in which there is a point in the plane of a unit square at K-rational distances from the four vertices of the square.
ON PROBLEMS OF
-CONNECTED GRAPHS FOR
Authors: STAŠ MICHAL , VALISKA JURAJ
Published: December 2020

A connected graph G is

$\mathcal {CF}$
-connected if there is a path between every pair of vertices with no crossing on its edges for each optimal drawing of G. We conjecture that a complete bipartite graph

$K_{m,n}$
is

$\mathcal {CF}$
-connected if and only if it does not contain a subgraph of

$K_{3,6}$
or

$K_{4,4}$
. We establish the validity of this conjecture for all complete bipartite graphs

$K_{m,n}$
for any

$m,n$
with

$\min \{m,n\}\leq 6$
, and conditionally for

$m,n\geq 7$
on the assumption of Zarankiewicz’s conjecture that

$\mathrm {cr}(K_{m,n})=\big \lfloor \frac {m}{2} \big \rfloor \big \lfloor \frac {m-1}{2} \big \rfloor \big \lfloor \frac {n}{2} \big \rfloor \big \lfloor \frac {n-1}{2} \big \rfloor $
.
‘Research sharing’ using social media: online conferencing and the experience of #BSHSGlobalHist
Authors: HOUGHTON JEMMA , LONGWORTH-DUNBAR ALEXANDER , SUGDEN NICOLA
Published: December 2020

In February 2020, the British Society for the History of Science hosted its first entirely digital conference via Twitter, with the dual goals of improving outreach and engagement with international historians of science, and exploring methods of reducing the carbon footprint of academic activities. In this article we discuss how we planned and organized this conference, and provide a summary of our experience of the conference itself. We also describe in greater detail the motivations behind its organization, and explore the good and bad dimensions of this relatively new kind of conferencing. As the climate crisis becomes more acute and, in turn, the pressure to reduce the carbon footprint of academic activities increases, we argue that digital conferences of this style will necessarily become more central to how academia operates. By sharing our own experiences of running such a conference, we seek to contribute to a rapidly growing body of knowledge on the subject that might be drawn on to improve our practices going forward. We also share some of our own ideas about how best to approach digital conference organization which helped us to make the most of this particular event.
ACYLINDRICAL HYPERBOLICITY OF ARTIN–TITS GROUPS ASSOCIATED WITH TRIANGLE-FREE GRAPHS AND CONES OVER SQUARE-FREE BIPARTITE GRAPHS
Authors: KATO MOTOKO , OGUNI SHIN-ICHI
Published: December 2020

It is conjectured that the central quotient of any irreducible Artin–Tits group is either virtually cyclic or acylindrically hyperbolic. We prove this conjecture for Artin–Tits groups that are known to be CAT(0) groups by a result of Brady and McCammond, that is, Artin–Tits groups associated with graphs having no 3-cycles and Artin–Tits groups of almost large type associated with graphs admitting appropriate directions. In particular, the latter family contains Artin–Tits groups of large type associated with cones over square-free bipartite graphs.
Molecular characterization of Polychromophilus parasites of Scotophilus kuhlii bats in Thailand
Authors: Chumnandee Chatree , Pha-obnga Nawarat , Werb Oskar , Matuschewski Kai , Schaer Juliane
Published: December 2020

Parasites of the haemosporidian genus Polychromophilus have exclusively been described in bats. These parasites belong to the diverse group of malaria parasites, and Polychromophilus presents the only haemosporidian taxon that infects mammalian hosts in tropical as well as in temperate climate zones. This study provides the first information of Polychromophilus parasites in the lesser Asiatic yellow bat (Scotophilus kuhlii) in Thailand, a common vespertilionid bat species distributed in South and Southeast Asia. The gametocyte blood stages of the parasites could not be assigned to a described morphospecies and molecular analysis revealed that these parasites might represent a distinct Polychromophilus species. In contrast to Plasmodium species, Polychromophilus parasites do not multiply in red blood cells and, thus, do not cause the clinical symptoms of malaria. Parasitological and molecular investigation of haemosporidian parasites of wildlife, such as the neglected genus Polychromophilus, will contribute to a better understanding of the evolution of malaria parasites.
Long-term trends in helminth infections of wood mice (Apodemus sylvaticus) from the vicinity of Malham Tarn in North Yorkshire, England
Authors: Behnke Jerzy M. , Rogan Michael T. , Craig Philip S. , Jackson Joseph A. , Hide Geoff
Published: December 2020

Helminth infections in wood mice (n= 483), trapped over a period of 26 years in the woods surrounding Malham Tarn in North Yorkshire, were analysed. Although 10 species of helminths were identified, the overall mean species richness was 1.01 species/mouse indicating that the helminth community was relatively depauperate in this wood mouse population. The dominant species wasHeligmosomoides polygyrus, the prevalence (64.6%) and abundance (10.4 worms/mouse) of which declined significantly over the study period. Because of the dominance of this species, analyses of higher taxa (combined helminths and combined nematodes) also revealed significantly declining values for prevalence, although not abundance. Helminth species richness (HSR) and Brillouin's index of diversity (BID) did not show covariance with year, neither did those remaining species whose overall prevalence exceeded 5% (Syphacia stroma,Aonchotheca murissylvaticiandPlagiorchis muris). Significant age effects were detected for the prevalence and abundance of all higher taxa,H. polygyrusandP. muris, and for HSR and BID, reflecting the accumulation of helminths with increasing host age. Only two cases of sex bias were found; male bias in abundance ofP. murisand combined Digenea. We discuss the significance of these results and hypothesize about the underlying causes.
Alexis de Tocqueville's Reluctant “Democratic Language”
Authors: Gerçek Salih Emre
Published: December 2020

Many readers of Alexis de Tocqueville have noted the ambiguity in his formulation of the term “democracy.” This essay suggests that this ambiguity can be clarified by considering what Tocqueville calls “democratic language”—i.e., the use of generalizations, abstractions, and personifications in writing and speech. Tocqueville investigates these novel linguistic devices to understand the transformation of language in democratic times. More importantly, he employs them to appropriate the Doctrinaires’ formulation of democracy and to criticize their legitimation of the July Monarchy's exclusive government. Yet Tocqueville's use of democratic language is a reluctant one. He finds that the tendency to use abstract and personified concepts obfuscates the political agency of citizens. Wary of the despotic effects of such obfuscation, Tocqueville argues that individuals must practice their concepts. In the context of the July Monarchy, this becomes a call for the extension of democratic rights and institutions.
Investigating the correlation between students’ perception of authenticity in assessment and their academic achievement in the associated assessment tasks
Authors: Ghosh Samrat , Brooks Benjamin , Ranmuthugala Dev , Bowles Marcus
Published: December 2020

The objective of this research was to investigate the factors of assessment that students undergoing authentic assessment perceived to be significant regarding their academic achievement. This project advanced past research by the authors which found that the academic achievement of seafarer students was significantly higher in a formatively implemented authentic assessment compared with a summative traditional assessment. The academic achievement (assessment scores) was based on the students’ performance in analysing information presented in a real-world context (authentic assessment) as opposed to the analysis of information presented devoid of a real-world context (traditional assessment). Using the data obtained from students undergoing the authentic assessment, this project correlated their perceptions of authenticity for factors of assessment to their scores in the associated task. Stage 1 focused on deriving the factors conceptually from the definition of the authentic assessment by the authors, based on which a perception survey questionnaire was designed. Stage 2 extracted new factors through a factor analysis conducted using the software SPSS. Both stages of investigation found that the factor of transparency of criteria was a significant predictor of the students’ academic achievement.
COVID-19 mortality in an area of northeast Brazil: epidemiological characteristics and prospective spatiotemporal modelling
Authors: Andrade L. A. , Gomes D. S. , Lima S. V. M. A. , Duque A. M. , Melo M. S. , Góes M. A. O. , Ribeiro C. J. N. , Peixoto M. V. S. , Souza C. D. F. , Santos A. D.
Published: December 2020

This study aimed to analyse the spatial–temporal distribution of COVID-19 mortality in Sergipe, Northeast, Brazil. It was an ecological study utilising spatiotemporal analysis techniques that included all deaths confirmed by COVID-19 in Sergipe, from 2 April to 14 June 2020. Mortality rates were calculated per 100 000 inhabitants and the temporal trends were analysed using a segmented log-linear model. For spatial analysis, the Kernel estimator was used and the crude mortality rates were smoothed by the empirical Bayesian method. The space–time prospective scan statistics applied the Poisson's probability distribution model. There were 391 COVID-19 registered deaths, with the majority among ⩾60 years old (62%) and males (53%). The most prevalent comorbidities were hypertension (40%), diabetes (31%) and cardiovascular disease (15%). An increasing mortality trend across the state was observed, with a higher increase in the countryside. An active spatiotemporal cluster of mortality comprising the metropolitan area and neighbouring cities was identified. The trend of COVID-19 mortality in Sergipe was increasing and the spatial distribution of deaths was heterogeneous with progression towards the countryside. Therefore, the use of spatial analysis techniques may contribute to surveillance and control of COVID-19 pandemic.