bluuebunny/crossref_metadata_2025 huggingface dataset:
Brown bear communication hubs: patterns and correlates of tree rubbing and pedal marking at a long-term marking site
Authors: Revilla Eloy , Ramos Fernández Damián , Fernández-Gil Alberto , Sergiel Agnieszka , Selva Nuria , Naves Javier
Published: January 2021

Chemical communication is important for many species of mammals. Male brown bears, Ursus arctos, mark trees with a secretion from glands located on their back. The recent discovery of pedal glands and pedal-marking at a site used for tree-rubbing led us to hypothesize that both types of marking form part of a more complex communication system. We describe the patterns of chemical communication used by different age and sex classes, including differences in the roles of these classes as information providers or receivers over four years at a long-term marking site. Using video recordings from a camera trap, we registered a total of 285 bear-visits and 419 behavioral events associated with chemical communication. Bears visited the site more frequently during the mating season, during which communication behaviors were more frequent. A typical visit by male bears consisted of sniffing the depressions where animals pedal mark, performing pedal-marking, sniffing the tree, and, finally, rubbing against the trunk of the tree. Adult males performed most pedal- and tree-marking (95% and 66% of the cases, respectively). Males pedal-marked and tree-rubbed in 81% and 48% of their visits and sniffed the pedal marks and the tree in 23% and 59% of visits, respectively. Adult females never pedal marked, and juveniles did so at very low frequencies. Females rubbed against the tree in just 9% of their visits; they sniffed the tree and the pedal marks in 51% and 21% of their visits, respectively. All sex and age classes performed pedal- and tree-sniffing. There were significant associations between behaviors indicating that different behaviors tended to occur during the same visit and were more likely if another individual had recently visited. These associations leading to repeated marking of the site can promote the establishment of long-term marking sites. Marking sites defined by trees and the trails leading to them seem to act as communication hubs that brown bears use to share and obtain important information at population level.
Fans Make Art: Authoring and Creativity in the Production of Fanvideos
Authors: De Souza-Leão André Luiz Maranhão , Moura Bruno Melo , Santana Italo Rogerio Correia de , Nunes Walber Kaíc da Silva , Henrique Vitor De Moura Rosa
Published: January 2021

The research aims to analyze how Brazilian produce fanvideos based on successful pop culture franchises. For such, assumes that fans are prosumers of pop culture in a context of participatory culture and that fanvideos are user-generated content propitiated by Web 2.0 technologies. A total of 257 fanvideos posted between April 2006 and February 2018 were analyzed through Interpretive Content Analysis. Five types of fanmade productions were identified: fandub, fanart, fan animation, fan music and fanfiction. Such production demonstrates that fanvideos reveal the fans' desire to make art, what occurs both as a way for the fans relate to the franchises they admire, as well as to express themselves based on them. By doing this, they wide the scope and the narrative possibilities of the franchises through intra- and inter-textualities in relation to the universe of pop culture and their own daily experiences. The research presents an original approach to user-generated content in association to fan production and the notion of prosumption. As limitation, the study is delimited to the Brazilian production of fanvideos. Future similar research could be carried out in other countries, as well as regarding other fan productions.
Takayasu Arteritis: a Systematic Review and Meta‐Analysis of Test Accuracy and Benefits and Harms of Common Treatments
Authors: Dua Anisha B. , Kalot Mohamad A. , Husainat Nedaa M. , Byram Kevin , Springer Jason M. , James Karen E. , Chang Lin Yih , Turgunbaev Marat , Villa‐Forte Alexandra , Abril Andy , Langford Carol , Maz Mehrdad , Chung Sharon A. , Mustafa Reem A.
Published: January 2021

Objective

Takayasu’s arteritis (TAK) is a granulomatous large‐vessel vasculitis primarily affecting the aorta and its proximal branches. TAK can be a difficult disease to diagnose and manage given the rarity of the disease as well as current limitations in biomarkers, imperfect imaging modalities, and few randomized controlled trials.

Methods

In developing the American College of Rheumatology/Vasculitis Foundation guideline for the management of TAK, we performed an extensive systematic literature review to guide our recommendations. We included RCTs first. When RCTs were not available, we included observational studies that reported on patient‐important outcomes for the intervention and comparison. When studies with comparative data were not available, we included case series that present patient‐important outcomes for either the intervention or the comparison.

Results

Three hundred forty‐seven articles were included for full review to answer 27 population, intervention, comparison, and outcome questions related to TAK. Ten studies were evaluated that addressed the use of glucocorticoids (GCs), non‐GC nonbiologic therapies, as well as biologics in treating TAK. A total of 33 studies, including 8 comparative studies, were included to determine the test accuracy of commonly available diagnostic tests for TAK.

Conclusion

This comprehensive systematic review synthesizes and evaluates the benefits and harms of different treatment options and the accuracy of commonly used tests for the management of TAK.
Fabrication of 17‐4PH Stainless Steel Foam by a Pressureless Powder Space Holder Technique
Authors: Hsu Chia-Ming , Tzeng Yu-Chih , Chen Shun-Fa , Chen Yu-Liang , Lee Huei-Long
Published: January 2021

High compressive strength closed‐cell porous 17‐4PH precipitation hardening stainless steel with three different porosities (30%, 40%, and 50%, volume percent) was manufactured using a novel pressureless powder space holder method. The compressive strengths of the as‐sintered 17‐4PH stainless steel foam with porosities of 30%, 40%, and 50% are 420, 275, and 187 MPa, respectively. The application of an H900 heat treatment to the as‐sintered porous 17‐4PH stainless steel can effectively improve the compressive strength due to the precipitation of ϵ‐Cu phases. It is shown that with this pressureless powder space holder method, it can efficiently produce closed‐cell porous 17‐4PH stainless steel and control its porosity.
A Biomimetic Transpiration Textile for Highly Efficient Personal Drying and Cooling
Authors: Miao Dongyang , Wang Xianfeng , Yu Jianyong , Ding Bin
Published: January 2021

Efficient sweat release and heat dissipation are required for functional textiles that improve comfort and productivity while being worn in daily life. However, the porous structure of textiles exhibits an opposite effect on water transport and heat transfer capacities, leading to a longstanding bottleneck for the design of multifunctional drying and cooling textiles. Here, a biomimetic transpiration textile based on the hierarchical and interconnected network of vascular plants is demonstrated for highly efficient personal drying and cooling. The transpiration‐inspired design offers a textile with distinct advantages, including a desired one‐way water transport index (1072%), rapid water evaporation rate (0.36 g h−1), and outstanding through‐plane (0.182 W m−1 K−1) and in‐plane (1.137 W m−1 K−1) thermal conductivities. Moreover, based on the optimized performance, plausible mechanisms are proposed and calculated to provide insight into the water transport and heat transfer within the hierarchical and interconnected network, which provide promising benefits to the development of multifunctional drying and cooling textiles. Overall, the successful synthesis of this biomimetic transpiration textile provides a comfortable microclimate to the human body, thus satisfying the growing demand for better health, productivity, and sustainability.
Regioselective Access to 3‐Ethylideneflavanones via Rhodium(I)‐Catalyzed 1,3‐Enyne Hydroacylation/Annulation Cascades
Authors: Chang Zhi‐Xin , Li Fu‐Rong , Xia Chengcai , Li Fei , Li Hong‐Shuang
Published: January 2021

The highly efficient synthesis of 3‐ethylideneflavanones through sequential rhodium(I)‐catalyzed hydroacylation of terminal aryl‐substituted 1,3‐enynes with chelating aldehydes and annulation is described. This straightforward protocol highlights an unprecedented C3‐regioselective hydroacylation of 1,3‐enynes, excellent functional group compatibility, and complete atom economy.

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Multi‐Ions Electrolyte Enabled High Performance Voltage Tailorable Room‐Temperature Ca‐Metal Batteries
Authors: Song Huawei , Su Jian , Wang Chengxin
Published: January 2021

Calcium metal batteries, as one of the promising alternatives beyond Li‐metal technology, is held back by the lack of suitable cathodes of considerable energy storage capability, and Ca anodes of long‐term stability and lower polarization potentials for Ca‐plating/stripping. Here, by recycling cellulose waste paper, feasible cathodes for Ca‐metal batteries of good high‐voltage and wide‐window‐voltage adaptability (0.005–4.9 V versus Ca/Ca2+), and impressive energy density (≈517.5 Wh kg−1 at 0.1 A g−1) are developed. Meanwhile, through tailorable Ca‐plating/stripping potentials (∆V ≈ 0.65 V) realized by a modified electrolyte of Li+, Ca2+, , and multi‐ions system, the proof‐of‐concept Ca‐metal batteries not only delivered enhanced storage capability (101 mAh g−1 versus 51 mAh g−1 at 0.1 A g−1 in the window voltage of 2.0–4.7 V) and cycling stability (≈77% capacity retention for 100 cycles), but also simultaneously show a high output average working voltage of ≈3.2 V. The work provides a hint that mixed metal deposition under multi‐ions electrolyte system may address the challenging issues faced by single alkali or alkaline‐earth metal batteries.
Metal‐Ion Capacitors with Anion Intercalation Process
Authors: Rajalekshmi Ambika Rajendran , Divya Madhusoodhanan Lathika , Natarajan Subramanian , Aravindan Vanchiappan
Published: January 2021

The advancement of the modern world demands high‐performance electrical energy storage devices such as metal‐ion capacitors and dual‐ion batteries, and they receive much attention recently with the merits of cost‐effectiveness, safety, environmental friendliness, and high operating voltage. This work emphasizes the metal‐ion capacitors (Li+, Na+, and K+) based on the dual‐carbon combination in which anion intercalation endorses the Faradaic reaction and cation involves in the non‐Faradaic process, promising for greater energy density. The role of graphite, anion graphite intercalation compounds, and the information about the megalo‐capacitance capacitor are first discussed. Subsequently, various influencing factors such as the effect of solvent, electrolyte, conducting salt, cations, and anions affecting the intercalation process are debated in detail. In addition, recently emerging various metal‐ion capacitors based on the anion intercalation process are also reviewed. The major challenges present in the development of the anion‐based hybrid capacitor are finally evaluated and an assessment to fulfill the goals for efficient energy storage is provided.
Computationally Assisted Design and Selection of Maneuverable Biological Walking Machines
Authors: Wang Jiaojiao , Zhang Xiaotian , Park Junehu , Park Insu , Kilicarslan Evin , Kim Yongdeok , Dou Zhi , Bashir Rashid , Gazzola Mattia
Published: January 2021

The intriguing opportunities enabled by the use of living components in biological machines have spurred the development of a variety of muscle‐powered biohybrid robots in recent years. Among them, several generations of tissue‐engineered biohybrid walkers have been established as reliable platforms to study untethered locomotion. However, despite these advances, such technology is not mature yet, and major challenges remain. Herein, steps are taken to address two of them: the lack of systematic design approaches, common to biohybrid robotics in general, and in the case of biohybrid walkers specifically, the lack of maneuverability. A dual‐ring biobot is presented which is computationally designed and selected to exhibit robust forward motion and rotational steering. This dual‐ring biobot consists of two independent muscle actuators and a four‐legged scaffold asymmetric in the fore/aft direction. The integration of multiple muscles within its body architecture, combined with differential electrical stimulation, allows the robot to maneuver. The dual‐ring robot design is then fabricated and experimentally tested, confirming computational predictions and turning abilities. Overall, a design approach based on modeling, simulation, and fabrication exemplified in this versatile robot represents a route to efficiently engineer complex biological machines with adaptive functionalities.
Efficient Amino‐Sulfhydryl Stapling on Peptides and Proteins Using Bifunctional NHS‐Activated Acrylamides
Authors: Silva Maria J. S. A. , Faustino Hélio , Coelho Jaime A. S. , Pinto Maria V. , Fernandes Adelaide , Compañón Ismael , Corzana Francisco , Gasser Gilles , Gois Pedro M. P.
Published: January 2021

Widely used reagents in the peptide functionalization toolbox, Michael acceptors and N‐hydroxysuccinimide (NHS) activated esters, are combined in NHS‐activated acrylamides for efficient chemoselective amino‐sulfhydryl stapling on native peptides and proteins. NHS‐activated acrylamides allow for a fast functionalization of N‐terminal cysteines (k2=1.54±0.18×103 M−1 s−1) under dilute aqueous conditions, enabling selectivity over other nucleophilic amino acids. Additionally, the versatility of these new bioconjugation handles was demonstrated in the cross‐linking of in‐chain or C‐terminal cysteines with nearby lysine residues. NHS‐activated acrylamides are compatible with the use of other cysteine selective reagents, allowing for orthogonal dual‐modifications. This strategy was successfully applied to the late‐stage functionalization of peptides and proteins with a PEG unit, fluorescent probe, and cytotoxic agent. The level of molecular control offered by NHS‐activated acrylamides is expected to promote amino‐sulfhydryl stapling technology as a powerful strategy to design functional bioconjugates.
cis‐Quinacridone‐Based Delayed Fluorescence Emitters: Seemingly Old but Renewed Functional Luminogens
Authors: Min Hyukgi , Park In Seob , Yasuda Takuma
Published: January 2021

Herein, we report a material design of linear cis‐quinacridone (cis‐QA) derivatives as delayed fluorescence luminogens. In contrast to the widely studied traditional trans‐isomers, the functionality of cis‐QA and its derivatives remains unexplored and unclarified. Through combined computational and experimental investigations, we revealed that cis‐QA derivatives can function as fascinating narrowband deep‐blue delayed fluorescence emitters for organic light‐emitting diodes (OLEDs). The best‐performing deep‐blue OLEDs incorporating these cis‐QA luminogens achieved high external electroluminescence quantum efficiencies of up to 19.0 % and high color purity with chromaticity coordinates of (0.13, 0.14).
Spin–Electric Coupling in a Cobalt(II)‐Based Spin Triangle Revealed by Electric‐Field‐Modulated Electron Spin Resonance Spectroscopy
Authors: Kintzel Benjamin , Fittipaldi Maria , Böhme Michael , Cini Alberto , Tesi Lorenzo , Buchholz Axel , Sessoli Roberta , Plass Winfried
Published: January 2021

A cobalt(II)‐based spin triangle shows a significant spin–electric coupling. [Co3(pytag)(py)6Cl3]ClO4⋅3 py crystallizes in the acentric monoclinic space group P21. The intra‐triangle antiferromagnetic interaction, of the order of ca. −15 cm−1 (H=−JSaSb), leads to spin frustration. The two expected energy‐degenerate ground doublets are, however, separated by a few wavenumbers, as a consequence of magnetic anisotropy and deviations from threefold symmetry. The Co3 planes of symmetry‐related molecules are almost parallel, allowing for the determination of the spin–electric properties of single crystals by EFM‐ESR spectroscopy. The spin–electric effect detected when the electric field is applied in the Co3 plane was revealed by a shift in the resonance field. It was quantified as ΔgE/E=0.11×10−9 m V−1, which in terms of frequency corresponds to approximately 0.3 Hz m V−1. This value is comparable to what was determined for a Cu3 triangle despite the antiferromagnetic interaction being 20 times larger for the latter.
Magnetic properties of a relativistic neutral vector boson gas at any temperature
Authors: Suárez‐González Lismary de la Caridad , Quintero Angulo Gretel , Pérez Martínez Aurora , Pérez Rojas Hugo
Published: January 2021

We study the magnetic properties of a relativistic neutral vector bosons gas under the action of a constant and uniform magnetic field. An analytical expression for the magnetization at any temperature is obtained, and a discussion of the influence of the antiparticles, the vacuum, and the Bose‐Einstein condensation over this magnitude is presented. We analyze the validity of the non‐relativistic and low‐temperature limits and comment on the relevance of our results in astrophysical scenarios.
The influence of rotation deceleration on the shape of a pulsar may reflect on the star's braking index
Authors: Frajuca Carlos , da Silva Bortoli Fabio , Magalhaes Nadja S.
Published: January 2021

Pulsars are stars whose electromagnetic radiation is observed to pulsate in well‐defined time intervals while they rotate as long as the electromagnetic signal is not emitted in the direction of the rotation axis. The frequencies of the pulses decay with time as quantified by the braking index (n). In the canonical model, n = 3 for all pulsars, but observational data yield n < 3. In this work, this model is modified to allow time change in the moment of inertia. According to that model, as the neutron star loses energy by the emission of electromagnetic radiation, its rotation decelerates under constant moment of inertia. Here, we propose that, as the rotation decelerates, the shape of the star changes due to an increasingly weaker centrifugal force that reduces its moment of inertia, a change that, under normal circumstances, would accelerate the star's rotation. In the case of pulsars, as the rotation decreases in view of electromagnetic energy loss, the rotation would decelerate less than in the canonical model, yielding a braking index less than three. This is a good result from our model, especially regarding stars with indices close to three. For lower indices, our model requires refinements as a complete explanation of braking index values probably demands that a series of phenomena be incorporated into the process.
What Can Text Mining Tell Us About Lithium‐Ion Battery Researchers’ Habits?
Authors: El‐Bousiydy Hassna , Lombardo Teo , Primo Emiliano N. , Duquesnoy Marc , Morcrette Mathieu , Johansson Patrik , Simon Patrice , Grimaud Alexis , Franco Alejandro A.
Published: January 2021

Artificial Intelligence (AI) has the promise of providing a paradigm shift in battery R&D by significantly accelerating the discovery and optimization of materials, interfaces, phenomena, and processes. However, the efficiency of any AI approach ultimately relies on rapid access to high‐quality and interpretable large datasets. Scientific publications contain a tremendous wealth of relevant data and these can possibly, but not certainly, be used to develop reliable AI algorithms useful for battery R&D. To address this, we present here a text mining study wherein we unravel lithium‐ion battery researchers’ habits when reporting results, reason on how these habits link to issues of lacking reproducibility and discuss the remaining challenges to be tackled in order to develop a more credible and impactful AI for battery R&D.
Recent Advances in Alkali Metal‐Ion Hybrid Supercapacitors
Authors: Xia Lishuang , Tang Bin , Wei Jinping , Zhou Zhen
Published: January 2021

An alkali metal‐ion hybrid supercapacitor is composed of a battery‐type electrode and a capacitor‐type one, with alkali metal ions transporting in the bulk of the whole device. In brief, batteries and supercapacitors are systematically combined in alkali metal‐ion hybrid supercapacitors accompanying with the fusion of both merits and exceptional performances. Such hybrid devices can deliver both high energy and power density, as well as long cycle life. In this review, the energy storage mechanisms, electrode materials and electrolytes are summarized for alkali metal‐ion hybrid supercapacitors, focusing on recent advances, current problems and future perspectives.
Topology Optimization Design of a Microchannel Plate Based on Velocity Distribution
Authors: Qiu Guiqian , Wei Peng , Huang Pingnan , Pan Minqiang
Published: January 2021

Velocity distribution plays an important role in the performance of microchannel devices. However, traditional microchannel plate design processes are based on experience with the existing models, which limits the ability to achieve optimal performance. Here, topology optimization is introduced into microchannel plate design, achieving a new microchannel plate with lower power dissipation and more uniform velocity distribution. A detailed design procedure was performed and an ANSYS Fluent analysis was carried out to further confirm the accuracy.
Not Carbon s–p Hybridization, but Coordination Number Determines C−H and C−C Bond Length
Authors: Vermeeren Pascal , van Zeist Willem‐Jan , Hamlin Trevor A. , Fonseca Guerra Célia , Bickelhaupt F. Matthias
Published: January 2021

A fundamental and ubiquitous phenomenon in chemistry is the contraction of both C−H and C−C bonds as the carbon atoms involved vary, in s–p hybridization, along sp3 to sp2 to sp. Our quantum chemical bonding analyses based on Kohn–Sham molecular orbital theory show that the generally accepted rationale behind this trend is incorrect. Inspection of the molecular orbitals and their corresponding orbital overlaps reveals that the above‐mentioned shortening in C−H and C−C bonds is not determined by an increasing amount of s‐character at the carbon atom in these bonds. Instead, we establish that this structural trend is caused by a diminishing steric (Pauli) repulsion between substituents around the pertinent carbon atom, as the coordination number decreases along sp3 to sp2 to sp.
Influence of Pore Structure and Metal‐Node Geometry on the Polymerization of Ethylene over Cr‐Based Metal–Organic Frameworks
Authors: Jongkind Maarten K. , Rivera‐Torrente Miguel , Nikolopoulos Nikolaos , Weckhuysen Bert M.
Published: January 2021

Metal–organic frameworks (MOFs) have received increasing interest as solid single‐site catalysts, owing to their tunable pore architecture and metal node geometry. The ability to exploit these modulators makes them prominent candidates for producing polyethylene (PE) materials with narrow dispersity index (Ð) values. Here a study is presented in which the ethylene polymerization properties, with Et2AlCl as activator, of three renowned Cr‐based MOFs, MIL‐101(Cr)‐NDC (NDC=2,6‐dicarboxynapthalene), MIL‐53(Cr) and HKUST‐1(Cr), are systematically investigated. Ethylene polymerization reactions revealed varying catalytic activities, with MIL‐101(Cr)‐NDC and MIL‐53(Cr) being significantly more active than HKUST‐1(Cr). Analysis of the PE products revealed large Ð values, demonstrating that polymerization occurs over a multitude of active Cr centers rather than a singular type of Cr site. Spectroscopic experiments, in the form of powder X‐ray diffraction (pXRD), UV/Vis‐NIR diffuse reflectance spectroscopy (DRS) and CO probe molecule Fourier transform infrared (FTIR) spectroscopy corroborated these findings, indicating that indeed for each MOF unique active sites are generated, however without alteration of the original oxidation state. Furthermore, the pXRD experiments indicated that one major prerequisite for catalytic activity was the degree of MOF activation by the Et2AlCl co‐catalyst, with the more active materials portraying a larger degree of activation.
Fluorinated Rings: Conformation and Application
Authors: Mondal Rajarshi , Agbaria Mohamed , Nairoukh Zackaria
Published: January 2021

The introduction of fluorine atoms into molecules and materials across many fields of academic and industrial research is now commonplace, owing to their unique properties. A particularly interesting feature is the impact of fluorine substitution on the relative orientation of a C−F bond when incorporated into organic molecules. In this Review, we will be discussing the conformational behavior of fluorinated aliphatic carbo‐ and heterocyclic systems. The conformational preference of each system is associated with various interactions introduced by fluorine substitution such as charge‐dipole, dipole‐dipole, and hyperconjugative interactions. The contribution of each interaction on the stabilization of the fluorinated alicyclic system, which manifests itself in low conformations, will be discussed in detail. The novelty of this feature will be demonstrated by presenting the most recent applications.
Endothelial NADPH oxidase 4 protects against angiotensin II‐induced cardiac fibrosis and inflammation
Authors: Wang Minshu , Murdoch Colin E. , Brewer Alison C. , Ivetic Aleksandar , Evans Paul , Shah Ajay M. , Zhang Min
Published: January 2021

Aims

Endothelial activation and inflammatory cell infiltration have important roles in the development of cardiac fibrosis induced by renin–angiotensin system activation. NADPH oxidases (Nox proteins) are expressed in endothelial cells (ECs) and alter their function. Previous studies indicated that Nox2 in ECs contributes to angiotensin II (AngII)‐induced cardiac fibrosis. However, the effects of EC Nox4 on cardiac fibrosis are unknown.

Methods and results

Transgenic (TG) mice overexpressing endothelial‐restricted Nox4 were studied alongside wild‐type (WT) littermates as controls. At baseline, Nox4 TG mice had significantly enlarged hearts compared with WT, with elongated cardiomyocytes (increased by 18.5%, P < 0.01) and eccentric hypertrophy but well‐preserved cardiac function by echocardiography and in vivo pressure–volume analysis. Animals were subjected to a chronic AngII infusion (AngII, 1.1 mg/kg/day) for 14 days. Whereas WT/AngII developed a 2.1‐fold increase in interstitial cardiac fibrosis as compared with WT/saline controls (P < 0.01), TG/AngII mice developed significant less fibrosis (1.4‐fold increase, P > 0.05), but there were no differences in cardiac hypertrophy or contractile function between the two groups. TG hearts displayed significantly decreased inflammatory cell infiltration with reduced levels of vascular cell adhesion molecule 1 in both the vasculature and myocardium compared with WT after AngII treatment. TG microvascular ECs stimulated with AngII in vitro supported significantly less leukocyte adhesion than WT ECs.

Conclusions

A chronic increase in endothelial Nox4 stimulates physiological cardiac hypertrophy and protects against AngII‐induced cardiac fibrosis by inhibiting EC activation and the recruitment of inflammatory cells.
Unveiling the Zirconium and Hafnium Speciation in Fluoride‐Nitric Acid Solutions by Paper Spray Ionization Mass Spectrometry Combined with DFT Calculations
Authors: Bertoli Alexandre C. , Miguita Ana Gabriella C. , Mingote Raquel M. , Augusti Rodinei , Duarte Hélio A.
Published: January 2021

Paper spray ionization mass spectrometry (PSI‐MS) was used to detect a variety of species of hafnium and zirconium present in an aqueous acid solution containing NO3− and F− anions. This solution mimetics the acid waters used in separation/extraction processes. Hence, the information provided by PSI‐MS is combined with the results achieved from DFT calculations to confirm the nature and stability of each species. In the adopted experimental conditions, Zr(IV) appears coordinated with F−, NO3− and H2O to generate mainly the dimer [Zr2F3OH(NO3)2(H2O)5]2+, among other complexes, with remarkable thermodynamic stability (−48.7 kcal mol−1). On the other hand, Hf(IV) emerges predominantly coordinated with NO3− and F− anions. The hafnium monomers [HfF4NO3]− and [HfF3(NO3)2]− have thermodynamic stability related to the electron pairing of the valence layer. In the gas phase, the fluoroanions of Zr(IV) demonstrated a high electronic affinity and free energy via DFT (−156.7 kcal mol−1) correlating thermodynamic stability to the experimental (−47 kcal mol−1), for the formation reaction of [ZrF5]−. Besides, the presence of fluoride and nitrate in the reaction mixture induces the formation of dimers connected in μ2‐F bridges, with coordination 7 and 8 of the central atom. Finally, the results described herein are promising studies of chemical speciation of cationic metals in an aqueous environment, a challenging subject whose importance will grow in the coming years.
Synthesis and Liquid Crystalline Self‐Assembly of Concave Diindoles with a Hydropentalene Core
Authors: Bühlmeyer Andrea , Ehni Philipp , Ullmann Dustin , Frey Wolfgang , Baro Angelika , Laschat Sabine
Published: January 2021

Fischer indole reaction of Weiss diketone with 4‐bromophenylhydrazine provided the 2,8‐dibromo‐hexahydropentaleno[2,1‐b:5,4‐b’]diindole key intermediate, which was converted to the target compounds by N‐protection/Suzuki cross‐coupling. Variation of protecting groups, mesogenic units, and their alkoxy substitution gave calamitic diindole mesogens. Both N‐protection and alkoxy chain influenced the mesomorphic properties of phenyl diindoles. Among the differently N‐protected derivatives only ethylcarbamate‐protected ones formed enantiotropic mesophases. Mesophase range and type were controlled by the chain lengths: chains≤C12 gave nematic (N) phases, diindoles with side chains≥C14 formed additional lower temperature smectic (SmA) phases. Irrespective of the chain lengths 4′‐alkyloxybiphenyl diindoles formed N and SmA phases upon first heating but tended to decomposition below their clearing points. X‐ray crystal structure analysis of bis(4′‐decyloxy)biphenyl diindole reveals that in the solid‐state the folding angle of the hydropentalene core caused an almost perpendicular orientation of the two indole/biphenyl parts with respect to each other.
The In Vitro Proinflammatory Properties of Water Accommodated Sediment Extracts from a Creosote-Contaminated US Environmental Protection Agency Superfund Site
Authors: Silva Rayna A. , Di Giulio Richard T. , Rice Charles D.
Published: January 2021

The southern branch of the Elizabeth River near Portsmouth, Virginia, USA, is one of the most creosote-polluted subestuaries in North America and the former location of the Atlantic Wood US Environmental Protection Agency Superfund site. We previously demonstrated that adult Atlantic Wood killifish collected in situ had severe hepatic lesions, including hepatoblastoma and hepatocellular carcinoma, as well as suppressed circulating antibody responses compared to a historical reference site. Moreover, several innate immune functions were higher in Atlantic Wood fish, including elevated expression of hepatic cyclooxygenase-2 (COX-2), suggesting a proinflammatory environment. To further examine the potential of Atlantic Wood contaminants to modulate innate immune function(s), the present study used RAW264.7 mouse macrophages as an in vitro model to develop new approach methodologies for rapid screening. Lipopolysaccharide (LPS)–stimulated nitric oxide secretion by macrophages is a rapid, sensitive, and predictive in vitro system for screening potentially immunotoxic contaminants as single compounds or as complex mixtures. Compared to the reference site, filter-sterilized Atlantic Wood sediment extracts (water accommodated fractions) induced nitric oxide and IL-6 secretion as well as inducible nitric oxide synthase and COX-2 proteins at levels comparable to or higher than those induced by LPS treatments alone. Extracts also increased phagocytic activity by macrophages. Using a limulus lysate assay, we show that bacterial endotoxin levels in Atlantic Wood extracts are higher than in reference extracts and that polymyxin-B chelation ameliorates proinflammatory effects. These findings illuminate the reality of sediment constituents other than toxic compounds previously associated with developmental abnormalities and carcinogenesis in killifish from the Atlantic Wood site. Perhaps these data also suggest the presence of contaminant-adapted consortia of sediment microbes at many heavily polluted sites worldwide compared to less contaminated sites. Environ Toxicol Chem 2021;40:1576–1585. © 2021 SETAC
Therapeutic perspective of thymoquinone: A mechanistic treatise
Authors: Butt Masood Sadiq , Imran Muhammad , Imran Ali , Arshad Muhammad Sajid , Saeed Farhan , Gondal Tanweer Aslam , Shariati Mohammad Ali , Gilani Syed Amir , Tufail Tabussam , Ahmad Ishtiaque , Rind Nadir Ali , Mahomoodally Mohamad Fawzi , Islam Saiful , Mehmood Zaffar
Published: January 2021

The higher utilization of fruits and vegetables is well known to cure human maladies due to the presence of bioactive components. Among these compounds, thymoquinone, a monoterpene and significant constituent in the essential oil of Nigella sativa L., has attained attention by the researchers due to their pharmacologies perspectives such as prevention from cancer, antidiabetic and antiobesity, prevention from oxidative stress and cardioprotective disorder. Thymoquinone has been found to work as anticancer agent against different human and animal cancer stages including propagation, migration, and invasion. Thymoquinone as phytochemical also downregulated the Rac1 expression, mediated the miR‐34a upregulation, and increased the levels of miR‐34a through p53, as well as also regulated the pro‐ and antiapoptotic genes and decreased the phosphorylation of NF‐κB and IKKα/β. In addition, thymoquinone also lowered the metastasis and ERK1/2 and PI3K activities. The present review article has been piled by adapting narrative review method and highlights the diverse aspects of thymoquinone such as hepatoprotective, anti‐inflammatory, and antiaging through various pathways, and further utilization of this compound in diet has been proven effective against different types of cancers.
A numerical comparison among different water‐based hybrid nanofluids on their influences on natural convection heat transfer in a triangular solar collector for different tilt angles
Authors: Prince Hasib A. , Rozin Enamul H. , Chowdhury Emdadul H. , Redwan Didarul A. , Mamun Mohammad A. H.
Published: January 2021

Natural convection inside a triangular solar collector is investigated numerically for different nanofluids and hybrid nanofluids in this study. The individual effects of Al2O3–water, carbon nanotubes (CNT)–water, and Cu–water nanofluids are observed for different solid volume fractions of nanoparticles (0%–10%). Three types of hybrid nanofluids are prepared using different ratios of Al2O3, CNT, and Cu nanoparticles in water. A comparison is made varying the Rayleigh numbers within laminar range (103–106) for different tilt angles (0°, 30°, 60°, and 90°) of the solar collector. The inclined surface of the triangular solar collector is isothermally cold and the bottom wall (absorber plate) is isothermally hot, whereas the vertical wall with respect to the absorber plate is considered adiabatic. Average Nusselt numbers along the hot wall for different parameters are observed. Streamlines and isotherm contours are also plotted for different cases. Dimensionless governing Navier–Stokes and thermal energy conservation equations are solved by Galerkin weighted residual finite element method. Better convective heat transfer is found for higher Rayleigh number, solid volume fraction, and tilt angle. In the case of hybrid nanofluid, increasing the percentage of the nanoparticle that gives better heat transfer performance individually results in enhancing natural convection heat transfer inside the enclosure.
Effect of necessity‐concern framework and polypharmacy on treatment adherence in psychiatric patients. Comparing an Argentinian with a Spanish sample
Authors: De las Cuevas Carlos , Villasante‐Tezanos Alejandro G. , Motuca Mariano , de Leon Jose
Published: January 2021

Objective

We aimed to replicate a prior Spanish study of medication adherence where logistic regression models provided highly significant odds ratios (ORs) for three continuous scores: necessity, concern and the necessity‐concern differential, and a dichotomous variable: skeptical attitude. Adherence ORs in the necessity‐concern framework were very strong in patients taking five or six medications.

Methods

The sample comprised consecutive adult psychiatric outpatients in Mendoza, Argentina. The necessity‐concerns framework was assessed using a subscale of the Beliefs about Medicines Questionnaire. Adherence (yes/no) to prescribed psychiatric medications was assessed by the Sidorkiewicz adherence tool.

Results

When compared with the Spanish sample, the Argentinian group (508 patients with 875 medications) was characterized by: (1) significantly stronger adherence ORs with the necessity‐concern framework, (2) significantly lower number of medications per patient and percentage of patients with marked psychiatric polypharmacy (≥4 medications), (3) though a higher number of medications still was significantly associated with poor adherence.

Conclusions

The Argentinian sample replicated the previous finding that patient beliefs regarding necessity and concern were associated with poor adherence to prescribed medications. Polypharmacy had an additive role decreasing adherence in both samples. In both samples, when prescribed ≥4 psychiatric medications, patients reported adherence to only two‐third of the medications.
Surface water‐groundwater exchange dynamics in buried‐valley aquifer systems
Authors: Wallace Corey D. , Soltanian Mohamad Reza
Published: January 2021

Groundwater is a primary source of drinking water worldwide, but excess nutrients and emerging contaminants could compromise groundwater quality and limit its usage as a drinking water source. As such contaminants become increasingly prevalent in the biosphere, a fundamental understanding of their fate and transport in groundwater systems is necessary to implement successful remediation strategies. The dynamics of surface water‐groundwater (hyporheic) exchange within a glacial, buried‐valley aquifer system are examined in the context of their implications for the transport of nutrients and contaminants in riparian sediments. High conductivity facies act as preferential flow pathways which enhance nutrient and contaminant delivery, especially during storm events, but transport throughout the aquifer also depends on subsurface sedimentary architecture (e.g. interbedded high and low conductivity facies). Temperature and specific conductance measurements indicate extensive hyporheic mixing close to the river channel, but surface water influence was also observed far from the stream‐aquifer interface. Measurements of river stage and hydraulic head indicate that significant flows during storms (i.e., hot moments) alter groundwater flow patterns, even between consecutive storm events, as riverbed conductivity and, more importantly, the hydraulic connectivity between the river and aquifer change. Given the similar mass transport characteristics among buried‐valley aquifers, these findings are likely representative of glacial aquifer systems worldwide. Our results suggest that water resources management decisions based on average (base) flow conditions may inaccurately represent the system being evaluated, and could reduce the effectiveness of remediation strategies for nutrients and emerging contaminants.
Assessment on micronutrient concentration after reclaimed water irrigation: A CASE study in green areas of Madrid*
Authors: Zalacáin David , Sastre‐Merlín Antonio , Martínez‐Pérez Silvia , Bienes Ramón , García‐Díaz Andrés
Published: January 2021

The use of reclaimed water to cope with water scarcity has become one of the main alternative resources in water‐deficit countries. Reclaimed water represents a significant component in integrated water resources management in the city of Madrid (Spain). Madrid City Council replaced the usual drinking water irrigation system by a reclaimed water one. This study assessed the effects of reclaimed water irrigation on micronutrient concentration (B, Cu, Fe, Mn and Zn) in the soil–plant system of two urban green areas in Madrid. Results showed that reclaimed water used in Madrid was adequate for irrigation regarding the studied micronutrients. Nevertheless, micronutrient concentration were slightly higher in reclaimed water than in drinking water. Soil organic matter (SOM) and pH had strong influence in some of the micronutrient concentrations in soils and in its bioavailability and transference to cedars (SOM ↔ B Soil, Cu Soil, Fe Soil; pH ↔ B Soil, Fe Soil, Mn Soil). There was no significant correlation between micronutrient concentration in irrigation water and in cedar leaves. Thus, foliar concentration of the studied micronutrients did not exceed toxic limits, even after 15 years of reclaimed water irrigation. Moreover, despite one park was irrigated with reclaimed water 10 years more than the other, reclaimed water irrigation plots did not show major differences in micronutrient concentration between the two parks.
Sesquiterpenoid bilobalide inhibits gastric carcinoma cell growth and induces apoptosis both in vitro and in vivo models
Authors: Liu Jinglei , Geng Zhen , Zhang Yingying , Alharbi Sulaiman Ali , Shi Yulong
Published: January 2021

Gastric carcinoma is one of the most aggressive types of cancer that ranks fifth among all cancer incidences and third in cancer mortality. As it exhibits a prolonged asymptomatic condition and high recurrence rate, it is a great challenge to treat gastric cancer. Traditional medicine that utilizes herbal phytochemicals to treat various diseases is a potent alternative for current allopathic treatment. Hence, we evaluated the potency of a phytochemical bilobalide for treating gastric cancer in in vitro and in vivo models. Bilobalide, a sesquiterpenoid, is present in the Ginkgo bilobaplant that belongs to the family of Ginkgoaceae. The cytotoxicity effect of bilobalide was evaluated in both gastric cancer (AGS) cells and normal gastric epithelial cells. Apoptosis‐inducing property of bilobalide against the AGS cell line was analyzed with different fluorescent staining techniques and terminal deoxynucleotidyl transferase dUTP nick‐end labeling assay, and cell cycle analysis was carried out by flow cytometry. The in vivo studies were assessed withN‐methyl‐N‐nitrosourea (MNU)‐induced gastric cancer in rats. Serum‐specific gastric markers were quantified and histopathological analysis of stomach tissue was performed. The expression of target‐signaling molecules was analyzed by a reverse‐transcription polymerase chain reaction. The in vitro results proved that bilobalide effectively suppressed the AGS cell growth and induced cell death by nuclear damage and apoptosis induction. The bilobalide treatment effectively arrested the cell cycle of AGS cells via inhibiting the PI3K‐signaling pathway. Our in vivo results also confirmed that the bilobalide persuasively inhibited the MNU‐induced gastric carcinoma via inhibiting the thioredoxin‐fold family proteins and inflammatory markers' expression. Overall, our results authentically prove that bilobalide possesses therapeutic potency to cure gastric carcinoma.
Scutebarbatine A induces cytotoxicity in hepatocellular carcinoma via activation of the MAPK and ER stress signaling pathways
Authors: Feng Pan‐pan , Qi You‐kun , Li Na , Fei Hong‐rong
Published: January 2021

Scutebarbatine A (SBT‐A), a diterpenoid alkaloid found in the root ofScutellaria barbataD. Don, has been reported to induce the apoptosis of A549 cells. In this study, we investigated the antitumor activity of SBT‐A in human hepatocellular carcinoma (HCC) cells and the potential underlying mechanisms. Our results showed that SBT‐A inhibited the growth of HCC cells in a dose‐dependent manner. SBT‐A treatment caused cell cycle arrest and decreased the expression of cyclin B1, cyclin D1, p‐Cdc2, and p‐Cdc25C. SBT‐A triggered cell apoptosis via a caspase‐dependent pathway, and cell viability was partially restored by pretreatment with the pan‐caspase inhibitor Z‐VAD‐FMK. In HCC cells, treatment with SBT‐A increased the phosphorylation of extracellular signal‐regulated kinase 1 and 2 (ERK1/2), c‐Jun N‐terminal kinase 1 and 2 (JNK1/2), and p38 mitogen‐activated protein kinase (p38 MAPK). Moreover, SBT‐A activated endoplasmic reticulum (ER) stress through the upregulation of protein kinase RNA‐like ER kinase (PERK), activating transcription factor 4 (ATF‐4), and CCAAT‐enhancer‐binding protein (C/EBP) homologous protein (CHOP). Our data indicate that SBT‐A inhibits the proliferation of HCC cells and triggers their apoptosis via the activation of MAPK and ER stress. SBT‐A is a potential agent for the treatment of HCC.
porE: A code for deterministic and systematic analyses of porosities
Authors: Trepte Kai , Schwalbe Sebastian
Published: January 2021

Accurate numerical calculations of porosities and related properties are of importance when analyzing metal–organic frameworks (MOFs). We present porE, an open‐source, general‐purpose implementation to compute such properties and discuss all results regarding their sensitivity to numerical parameters. Our code combines the numerical efficiency of Fortran with the user‐friendliness of Python. Three different approaches to calculate porosities are implemented in porE, and their advantages and drawbacks are discussed. In contrast to commonly used implementations, our approaches are entirely deterministic and do not require any stochastic averaging. In addition to the calculation of porosities, porE can calculate pore size distributions and offers the possibility to analyze pore windows. The underlying approaches are outlined, and pore windows are discussed concerning their impact on the analyzed porosities. Comparisons with reference values aim for a clear differentiation between void and accessible porosities, which we provide for a small benchmark set consisting of eight MOFs. In addition, our approaches are used for a bigger benchmark set containing 370 MOFs, where we determine linear relationships within our approaches as well as to reference values. We show how these relationships can be used to derive corrections to a give porosity approach, minimizing its mean error. As a highlight we show how complex workflows can be designed with a few lines of Python code using porE.