bluuebunny/crossref_metadata_2025 huggingface dataset:
Heart failure with preserved ejection fraction in coronavirus disease 2019 patients: the promising role of diuretic therapy in critically ill patients
Authors: Chitsazan Mitra , Amin Ahmad , Chitsazan Mandana , Ziaie Naghmeh , Amri Maleh Parviz , Pouraliakbar Hamidreza , Von Haehling Stephan
Published: January 2021

The impact of severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) on diastolic function is less known. We describe a 46‐year‐old man with a history of mild hypertension who presented to the emergency department with fever, cough, and myalgia for 2 days. The patient was tested positive for SARS‐CoV‐2. He was admitted and started on a combination of antiviral and antimicrobial therapy. He developed respiratory distress 2 days later, and O2 saturation declined. Blood tests showed an increased N‐terminal pro‐B type natriuretic peptide (NT‐proBNP) level, and echocardiography showed normal left ventricular ejection fraction and E/e′ ratio of 16. Computed tomography scan showed interstitial pulmonary oedema and prominent peripheral pulmonary vascular markings. Given these findings, heart failure with preserved ejection fraction (HFpEF) was considered. Low‐dose diuretic was started, and fluid administration was restricted, resulting in a decrease in NT‐proBNP level, clinical and haemodynamic stabilization, and improved oxygenation. This case highlights the occurrence of HFpEF in coronavirus disease 2019.
The advantages, pitfalls and limitations of guideline‐directed medical therapy in patients with valvular heart disease
Authors: Gill Harminder , Chehab Omar , Allen Christopher , Patterson Tiffany , Redwood Simon , Rajani Ronak , Prendergast Bernard
Published: January 2021

Heart failure is an inevitable end‐stage consequence of significant valvular heart disease (VHD) that is left untreated and increasingly encountered in an ageing society. Recent advances in transcatheter procedures and improved outcomes after valve surgery mean that intervention can (and should) be considered in all patients – even the elderly and those with multiple comorbidities ‐ at earlier stages of the natural history of primary VHD, before the onset of irreversible left ventricular dysfunction (and frequently before the onset of symptoms). All patients with known VHD should be monitored carefully in the setting of a heart valve clinic and those who meet guideline criteria for surgical or transcatheter intervention referred for intervention without delay.

High quality evidence for the use of medical therapy in VHD is limited and achieving target doses in an elderly and comorbid population frequently challenging. Furthermore, determining whether the valve or ventricle is the principal disease driver is crucial (although the distinction is not always binary, and often unclear). Guideline‐directed medical therapy remains the mainstay of treatment for secondary mitral regurgitation ‐ although up to 50% of patients may fail to respond and should be considered for cardiac resynchronization, transcatheter or surgical valve intervention. Early and definitive management strategies are essential and should be overseen by a specialist Heart Team that includes a Heart Failure specialist. In this article, we provide an evidence‐based summary of approaches to the medical treatment of VHD and clinical guidance for the best management of patients in situations where high quality evidence is lacking.
Temporal trends in mortality and readmission after acute heart failure: a systematic review and meta‐regression in the past four decades
Authors: Kimmoun Antoine , Takagi Koji , Gall Emmanuel , Ishihara Shiro , Hammoum Pierre , El Bèze Nathan , Bourgeois Alexandre , Chassard Guillaume , Pegorer‐Sfes Hugo , Gayat Etienne , Solal Alain C. , Hollinger Alexa , Merkling Thomas , Mebazaa Alexandre ,   METAHF Team
Published: January 2021

Aims

Acute heart failure (AHF) is frequent and life‐threatening disease. However, innovative AHF therapies have remained limited, and care is based on experts' opinion. Temporal trends and benefits of long‐term oral cardiovascular medications on AHF outcomes remain uncertain.

Methods and results

This study is registered with PROSPERO (CRD42018099885). A systematic review ranging from 1980 to 2017, searched AHF studies with more than 100 patients that reported death and/or readmission. Primary outcomes were temporal trends, assessed by meta‐regression, for 30‐day or 1‐year all‐cause death and/or readmission rates. Secondary outcomes were temporal trends of oral cardiovascular therapies and their influence on primary outcomes. Among the 45 143 studies screened, 285 were included, representing 15 million AHFs. In the past decades, though mortality and readmission remain high, there was a decline in 30‐day all‐cause death [odds ratio (OR) for a 10‐year increment: 0.74, 95% confidence interval (CI) 0.61–0.91; P = 0.004] that persisted at 1 year (OR 0.86, 95% CI 0.77–0.96; P = 0.007), while 30‐day and 1‐year all‐cause readmission rate remained roughly unchanged. Trends of primary outcomes were linear and did not differ among continents. Decline in 1‐year all‐cause death rate correlated with high proportions of oral or beta‐blockers, especially when combined with oral renin–angiotensin–aldosterone system inhibitors, but not with diuretics while trends in readmission remained unchanged with these therapies.

Conclusions

Although AHF outcomes remain poor, the present study revealed global favourable trends of survival after AHF episodes probably associated with greater use of oral neurohormonal antagonists. The present study urges to implement the combination of oral renin–angiotensin–aldosterone system inhibitors and beta‐blockers in patients at risk of AHF.
Energy Upconversion in Rare‐Earth‐Doped Tin‐Based Double Halo Perovskites, A2SnCl6 (A = K, Rb, and Cs)
Authors: Nagarajan Rajamani , Ahmad Shahzad , Kumar Manish , Gupta Mohini , Vijaya Prakash G.
Published: January 2021

A wet chemical methodology has been developed to synthesize the undoped and rare‐earth‐doped A2SnCl6 samples (A = K, Rb, and Cs) in cubic symmetry. The double perovskite (K2PtCl6) structure of these samples was confirmed from their PXRD, SAED, FTIR, and Raman spectra. The crystallites showed octahedral morphology in the FESEM and HRTEM images. The optical band gap of undoped A2SnCl6 increased with an increase in the size of the alkali metal ion. Eu3+ and Tb3+ (5 mol‐%) doped A2SnCl6 showed intense red‐orange and green emission when excited at 380 nm. The various radiative properties of the emission bands were analyzed using the Judd‐Ofelt theory. Yb3+/Er3+ co‐doped A2SnCl6 showed multicolor upconversion under 980 nm excitation, and the emission region varied with the alkali metal. These samples show bright emission with optimum CCT and CIE coordinates, indicating that the rare‐earth‐doped A2SnCl6 samples are suitable in applications involving Near‐UV and Near‐IR excitations.
Revisiting the HKUST‐1/S Composite as an Electrode for Li‐S Batteries: Inherent Problems That Hinder Its Performance
Authors: de Haro Jorge , Benítez Almudena , Caballero Álvaro , Morales Julián
Published: January 2021

A composite formed by the HKUST‐1 metal‐organic framework (MOF) and sulfur (S) was studied as an electrode for Li‐S batteries. For preparation, a simple milling procedure in ethanol, to facilitate its homogeneity, was used instead of melt diffusion. Different instrumental techniques were used to characterize the structural, morphological and textural properties of the compound. The results revealed a MOF with a high degree of purity, a high specific surface area and a dual micropore and mesopore system. Although capacity retention is good, losing 0.88 mAh g−1 per cycle, capacity values are low, 200 mAh g−1 at 100 cycles recorded at C/10 rate. Furthermore, the electrode only gives a moderate electrochemical performance at intermediate current rates. In parallel, a review was carried out of the reported results of this MOF for this application. Although better performances of the HKUST‐1 MOF have been published for this application, in some cases, the lack of experimental data to confirm them and serious doubts about the actual content of S in the composite bring the results into question. Only by increasing the additive content, working with low S loading, increasing the measurement voltage window and lowering the current rate can the electrode deliver higher capacities. The inherent problems of this MOF and others with similar properties are indeed their insulating character since the textural properties are adequate for S impregnation and absorption of the polysulfides formed.
Direct Assessment of Ultralow Li+ Jump Rates in Single Crystalline Li3N by Evolution‐Time‐Resolved 7Li Spin‐Alignment Echo NMR
Authors: Gadermaier Bernhard , Hogrefe Katharina , Heitjans Paul , Wilkening H. Martin R.
Published: January 2021

Diffusion processes of small cations and anions play important roles in many applications such as batteries and sensors. Despite the enormous progress we have witnessed over the past years in characterizing the irregular movement of ions such as Li+, new methods able to sharpen our view and understanding of fast and slow diffusion phenomena are steadily developed. Still, very few techniques are, however, available to directly sense extremely slow Li+ diffusion processes. Here, we took advantage of 1D evolution‐time resolved 7Li spin‐alignment echo NMR that is able to probe the extremely slow interlayer Li+ hopping process in layer‐structured Li3N, which served as a model substance for our purposes. The use of single crystals enabled us to study this translational process without being interfered by the fast intralayer Li+ motions. At 318 K the corresponding jump rate of interlayer dynamics turned out to be in the order of 2500(200) s−1 resulting in a diffusion coefficient as low as 1×10−17 m2 s−1, which is in excellent agreement with results from literature. The method, comparable to 1D and 2D NMR exchange spectroscopy, relies on temporal fluctuations of electric interactions the jumping ions are subjected to. 7Li single crystal 1D SAE NMR offers new opportunities to precisely quantify slow Li+ diffusion processes needed to validate theoretical models and to develop design principles for new solid electrolytes.
Design and Synthesis of Supramolecular Phosphatases Formed from a Bis(Zn2+‐Cyclen) Complex, Barbital‐Crown‐K+Conjugate and Cu2+for the Catalytic Hydrolysis of Phosphate Monoester
Authors: Rahman Akib Bin , Okamoto Hirokazu , Miyazawa Yuya , Aoki Shin
Published: January 2021

The development of artificial mimics of natural enzymes such as hydrolases and phosphatases is one of the great challenges in bioorganic and bioinorganic chemistry and related sciences. Supramolecular strategies are one of the useful methods to construct artificial catalysts as mimics of natural enzymes and to understand their reaction mechanisms. Herein, we report on the formation of amphiphilic supramolecular phosphatases by the 2 : 2 : 2 self‐assembly of a bis(Zn2+‐cyclen) complex (cyclen=1,4,7,10‐teraazacyclododecane) containing a 2,2′‐bipyridyl (bpy) linker and one long alkyl chain (Zn2L3), 5,5‐diethylbarbituric acid (Bar) derivative functionalized with 1‐aza‐18‐crown‐6 ether and Cu2+in a two‐phase solvent system (CHCl3/H2O). We hypothesized that crown ether moiety of the Bar‐crown ether conjugate would form complexes with alkaline ions and other metal ions such as Li+, Na+, K+, Rb+, Mg2+and La3+in organic phase to mimic the Mg2+found as the third metal ion in the active site of alkaline phosphatase (AP). The results indicate that the 2 : 2 : 2 : 4 complexes of Zn2L3, a Bar block equipped with the 18‐crown‐6 ether, Cu2+and alkaline metal are constructed in a two‐phase solvent system. The resulting complexes have a higher hydrolysis activity for mono(4‐nitrophenyl)phosphate (MNP) in the presence of K+than that in the presence of Li+, Na+, Rb+, Mg2+and La3+and a greater hydrolysis activity than our previous supermolecules having no crown ether part, suggesting that crown ether‐K+complex located in close proximity to the Cu2(μ‐OH)2core contributes to the acceleration of the MNP hydrolysis.
2,6‐Diisopropylphenyl‐Substituted Bismuth Compounds: Synthesis, Structure, and Reactivity
Authors: Dunaj Tobias , Dollberg Kevin , Ritter Christian , Dankert Fabian , von Hänisch Carsten
Published: January 2021

The 2,6‐diisopropylphenyl (Dipp) substituent is introduced to diaryl bismuth chemistry. Dipp2BiBr (1‐Br) was prepared by a Grignard reaction and subsequently used as precursor for synthesis of the other diaryl halido bismuthanes Dipp2BiX (1‐X, X=F, Cl, I) and the corresponding triflate Dipp2BiOTf (1‐OTf). Moreover, 1,1,2,2‐tetrakis(2,6‐diisopropylphenyl)dibismuthane (2) was prepared. All isolated compounds were characterized via single crystal X‐ray diffraction analysis, NMR spectroscopy, IR spectroscopy, and elemental analysis. Furthermore, the reactivity of a dibismuthane towards elemental sulfur was investigated, and the formed dibismuthanyl tri‐ and pentasulfide (3 a, 3 b) were characterized by single crystal X‐ray analysis. Functionalization of the diaryl halido bismuthanes with LiPtBu2 or tBu2PTMS (TMS=SiMe3) gives access to the interpnictogen compound Dipp2Bi−PtBu2 (4), which shows a rare example of a covalent Bi−P bond.
Bis‐Cyclometallated Iridium(III) Complexes with Bidentate Ligands Containing One or Two Pyridylideneamine (PYE) Donors: Influence of PYE Substitution (para or ortho) on Complexation
Authors: Abdolla Noreldin S. Y. , Davies David L. , Singh Kuldip
Published: January 2021

Six pyridylideneamine (PYE)‐containing bidentate ligands and their bis‐cyclometallated Ir(III) complexes have been synthesised and fully characterised. The PYE groups show a contribution from a neutral imine resonance form and a zwitterionic pyridinium form. NMR spectroscopy of the para‐substituted ligands and complexes show those with a C6H4 bridging group have the fastest PYE rotation. X‐ray crystallography of p‐1 and p‐3 shows the PYE N‐donor is trigonal planar whereas for the ortho‐complexes it is more pyramidalized implying an increased contribution of the zwitterionic resonance form for the ortho‐complexes.
High‐Performance Catalysts Derived from Cupric Subcarbonate for Selective Hydrogenation of Acetylene in an Ethylene Stream
Authors: Lu Chenyang , Zeng Aonan , Wang Yao , Wang Anjie
Published: January 2021

A high‐performance base metal catalyst for acetylene selective hydrogenation was prepared from cupric subcarbonate (Cu2(OH)2CO3) by thermal treatment with an acetylene‐containing gas followed by hydrogen reduction. The characterization results revealed that the copper catalyst was composed of interstitial copper carbide (CuxC) and metal Cu, which were embedded in porous carbon matrix. The CuxC crystallites, which showed outstanding hydrogenation activity, were derived from the hydrogen reduction of copper (II) acetylide (CuC2) which was generated from the reaction between acetylene and Cu2(OH)2CO3. The Cu particles and porous carbon were generated from the unavoidable thermal decomposition of CuC2. The prepared Cu‐derived catalyst completely removed the acetylene impurity in an ethylene stream with a very low over‐hydrogenation selectivity at 110 °C and atmospheric pressure. No obvious deactivation was observed in a 180‐h test run. In the Cu‐derived catalyst, CuxC served as the catalytic site for H2 dissociation, Cu mainly functioned as the site for selective hydrogenation of acetylene, whereas the porous carbon matrix posed a steric hindrance effect on the chain growth of linear hydrocarbons so as to suppress the undesired oligomerization.
Easily Separable Cyclic Oligosilanes with p‐Methoxyphenyl Groups and Their Stereoselective Functionalization
Authors: Omatsu Yamato , Mizuhata Yoshiyuki , Tokitoh Norihiro
Published: January 2021

Novel cyclic oligosilanes with trimethylsilylmethyl and aryl groups at each silicon ring atom were synthesized. The reductive condensation of a dichlorosilane having a phenyl group as an aryl group gave five‐ and six‐membered cyclic oligosilanes as mixtures of their stereoisomers. On the other hand, the use of p‐methoxyphenyl group instead of phenyl group resulted in the formation of four‐ and five‐membered cyclic oligosilanes, from which each stereoisomer was separable and identified spectroscopically and structurally. Interestingly, the dearylative pentatriflation of the isolated cyclic pentasilanes yielded the sole pentatriflated cyclopentasilane from any stereoisomer. In addition, its further chlorination, bromination, and iodination quantitatively afforded the sole stereoisomer of the corresponding pentahalocyclopentasilanes.
Synthesis of 3(2H)‐Furanones: A Review
Authors: Omanakuttan Vishnu K. , John Jubi , Hopf Henning
Published: January 2021

The present review describes the methods reported for the synthesis of 3(2H)‐furanones. This heterocycle forms the core structure of a number of natural products and biologically active scaffolds. We have covered all reports available on the synthesis of 3(2H)‐furanone derivatives and have divided the review into several sections based on the substitution patterns present in the heterocycle. Special emphasis is given to the generality and the mechanistic rationalizations of each methodology. In addition, all total syntheses reported for the synthesis of 3(2H)‐furanone containing natural products are reviewed by highlighting the heterocycle synthesis.
Facile Construction of Benzofulvene Scaffold from Tetraaryl[3]cumulene Through Electrophilic Iodocyclization
Authors: Yagishita Fumitoshi , Hoshi Keita , Yoshida Yasushi , Ueta Shoko , Minagawa Keiji , Imada Yasushi , Kawamura Yasuhiko
Published: January 2021

We found that the reaction of tetraaryl[3]cumulenes with N‐iodosuccinimide afforded the corresponding iodinated triarylbenzofulvenes with high yields under mild reaction conditions. Unsymmetrical tetraaryl[3]cumulenes underwent regioselective reactions to give a single isomer of benzofulvenes depending on the aryl substituents. The obtained iodinated benzofulvene was successfully used as aryl iodide for common cross‐coupling reactions, and the corresponding tetrasubstituted benzofulvenes was easily accessed via Suzuki–Miyaura and Sonogashira cross‐coupling reactions, respectively.
Mechanochemistry as a Sustainable Method for the Preparation of Fluorescent Ugi BODIPY Adducts
Authors: Pérez‐Venegas Mario , Arbeloa Teresa , Bañuelos Jorge , López‐Arbeloa Iñigo , Lozoya‐Pérez Nancy E. , Franco Bernardo , Mora‐Montes Héctor M. , Belmonte‐Vázquez José L. , Bautista‐Hernández Claudia I. , Peña‐Cabrera Eduardo , Juaristi Eusebio
Published: January 2021

Mechanochemistry, that is, the use of mechanical energy produced by milling or grinding to perform chemical transformations, was used as a green strategy using a minimal amount of solvent for the preparation of highly valuable formyl functionalized BODIPY dyes. The electronic properties of the meso‐aryl group play a key role in the fluorescence response of the adducts resulting from the Ugi reaction. Such an understanding of the molecular structure‐fluorescence interplay explains the brightness of these dyes in the cellular media monitored by fluorescence imaging. In the present report, we provide flow cytometry and fluorescence microscopy evidence that the novel dyes efficiently stain peripheral blood mononuclear cells (PBMCs) and Candida albicans cells without disturbing cell integrity. Moreover, it is demonstrated that by staining C. albicans cells, we can monitor the early and late steps of phagocytosis, using human monocyte‐derived macrophages. The dye series presented herein represent a novel application for formyl functionalized BODIPYs, expanding their applications in monitoring biological processes.
Decarbonylative Issues Involved in Ru(II)‐Catalyzed [6+2−1] Annulation Reaction of Hydroxychromone with Alkyne: A DFT Study
Authors: Ling Baoping , Wang Jiarong , Liu Yuxia , Jiang Yuan‐Ye , Liu Peng , Feng Jin , Bi Siwei
Published: January 2021

Density functional theory calculations have been performed to explore the Ru‐catalyzed decarbonylative annulation reaction of 3‐hydroxy‐2‐phenyl‐chromone with an alkyne to synthesize spiroindenebenzofuranones. A Ru(II)−Ru(0)−Ru(II) rather than a Ru(II)−Ru(IV)−Ru(II) transformation was found involved in the decarbonylation process, which is responsible for the sequence of alkyne insertion/decarbonylation. Oxidative addition of C(carbonyl)−C(carbonyl) bond to Ru(0) and the Ru(II)−C(sp2) bond formation were confirmed to be favorable for the decarbonylation, meanwhile oxidative addition of C(carbonyl)−C(carbonyl) bond to Ru(0) is likely to be the rate‐determining step for the entire catalytic cycle. It is predicted that the regeneration of the catalyst was achieved by the oxidation of air oxygen in the absence of other oxidants. The current theoretical study provides new insights into the decarbonylative annulation.
Lewis Acid‐Catalyzed Nucleophilic Substitutions of Benzylic Alcohols with Sulfamides
Authors: Oda Ryoga , Nakata Kenya
Published: January 2021

Nucleophilic substitutions of benzylic alcohols with sulfamides were achieved using an FeCl3 Lewis acid catalyst in MeNO2. It was necessary to adjust the reaction conditions to obtain efficient yields depending on the stability of the carbocation intermediates. The reaction could easily be performed, and it was revealed that a variety of diarylmethanols and benzylic alcohols were applicable to the reaction, irrespective of the type and position of the substituents. The sulfamide moieties were easily deprotected and converted into amine groups.
Two‐Step Protocol for Iodotrimethylsilane‐Mediated Deoxy‐Functionalization of Alcohols
Authors: Chen Yuming , He Ru , Song Hongjian , Yu Guoqing , Li Chenglin , Liu Yuxiu , Wang Qingmin
Published: January 2021

We have developed a two‐step protocol for iodotrimethylsilane‐mediated deoxy‐functionalization of primary and secondary alcohols to afford products containing a C−N, C−S, or C−O bond. In the first step the alcohol undergoes iodination with iodotrimethylsilane, and in the second, the iodine atom is replaced by a N, S, or O nucleophile. Compared with traditional Mitsunobu reaction, non‐acidic pre‐nucleophiles can be used, and the reaction proceeds with retention of configuration. This operationally simple, highly efficient protocol can be used for some natural products and small‐molecule drugs containing hydroxy‐group.
Controlling γ‐Peptide Helicity with Stereoselective Fluorination
Authors: Lawer Aggie , Hunter Luke
Published: January 2021

Peptides that are composed of backbone‐extended amino acids can adopt conformations resembling natural α‐peptidic motifs, making them promising scaffolds for biological and medicinal chemistry. In order to unlock the full potential of this class of molecules, the ability to control their secondary structures is essential. Here we show that stereoselective fluorination can be harnessed as a tool for influencing the helical character of a γ‐hexapeptide. Fluorination is shown to either stabilize or disrupt the 9‐helical conformation depending on the C−F stereochemistry, and fluorination also sets the handedness of the helix. These results provide fundamental knowledge that could expedite the future development of backbone‐extended peptides for medicinal applications.
Perfluorophenyl‐Perfluorophenyl Stacking‐Promoted Aggregation‐Induced Emission Enhancement of Crystalline 5‐Aryloxy‐3H‐Indole
Authors: Funabiki Kazumasa , Yamada Kengo , Matsueda Hisaki , Arisawa Yuta , Agou Tomohiro , Kubota Yasuhiro , Inuzuka Toshiyasu , Wasada Hiroaki
Published: January 2021

Introduction of a perfluorophenyloxy group at the 5‐position of 3,3‐dibutyl‐2‐methyl‐3H‐indole efficiently promotes aggregation‐induced emission enhancement in both the crystalline solid‐state and in highly concentrated ethanolic solutions of the resultant analog. The phenomenon is attributed to aggregate formation, arising from perfluorophenyl‐perfluorophenyl stacking between the 3H‐indole units, the occurrence of which was deduced from single‐crystal X‐ray analysis of 3,3‐dibutyl‐5‐perfluorophenyloxy‐2‐methyl‐3H‐indole.
Molecularly Imprinted Potentiometric Sensor for Nanomolar Determination of Pioglitazone Hydrochloride in Pharmaceutical Formulations
Authors: El‐Beshlawy Menna M. , Abdel‐Haleem Fatehy M. , Barhoum Ahmed
Published: January 2021

Pioglitazone Hydrochloride (PG) is an insulin‐sensitizing drug and is indicated for the treatment of type II diabetes. In this study, newly molecularly imprinted electrochemical sensors were constructed for the potentiometric determination of PG in the pharmaceutical formulations (Diabetonorm® 45 and 15 mg) with high accuracy and precision. The MIP particles (ionophore) were prepared by using the PG drug as a template, acrylamide (AC) or methacrylic acid (MAA) as a functional monomer, and ethylene glycol dimthacrylate (EGDMA) as a cross‐linker. The best MIP was synthesized from AC as a functional monomer, AC‐MIP. The best sensor (CPEs) was formulated from graphite (47 wt%) as a carbon source, AC‐MIP (5 wt.%) as an ionophore, PMA (1 wt%) as an ion‐exchanger, DNPOE (47 wt.%) as a conductive oil so‐called plasticizer. The best CPE electrode exhibited response slope to the Nernstian slope of 63.0 mV Decade−1, linear dynamic range of 10−8–10−4 M with the detection limit of 1.0×10−8 M, along with high reversibility, short response time 30 sec, and a long lifetime. The constructed biosensors showed high selectivity against similar interfering species (e. g. arabinose, galactose, lactose, maltose, glucose, Ba2+, Cu2+, Na+, Zn2+, Mg2+, Fe2+, Ca2+, NH4+).
Facile Green Synthesis of NiO/NiCo2O4 Nanocomposite as an Efficient Electrochemical Platform for Determination of Dopamine
Authors: Amiri Mahnaz , Akbari Javar Hamid , Mahmoudi‐Moghaddam Hadi
Published: January 2021

The synthesis of NiO/NiCo2O4 nanoparticles by an eco‐friendly, fast, simple and cost‐effective approach employing Urtica extract is reported in this study. The NiO/NiCo2O4 nanocomposite were characterized using VSM, FTIR, XRD, and SEM techniques. Moreover, to construct a modified carbon paste electrode, NiO/NiCo2O4 were employed and this sensor was used for dopamine (DA) detection. Using cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques, the electrochemical behavior of dopamine at the NiO/NiCo2O4/CPE was investigated. Analysis of dopamine, with a limit of detection (LOD) equal to 0.04 μM, in the concentration range of 0.1–100.0 μM, was facilitated by NiO/NiCo2O4/CPE. Moreover, the satisfactory selectivity for DA determination in the presence of uric acid (UA) and ascorbic acid (AA), was obtained. The suggested new sensor displayed a good reproducibility, sensitivity, and stability for determination of DA in drug and biological samples.
Unbiased Selectivity Coefficients of Potentiometric Sensors Using Thin Membrane Layers
Authors: Zdrachek Elena , Bakker Eric
Published: January 2021

Solid‐contact ion‐selective electrodes with thin membranes can more easily achieve complete ion exchange at the sample‐membrane interface, giving unbiased selectivity coefficients. The calculated reconditioning rate corresponds well to experimental data. Alternatively, the redox state of the conducting polymer may be electrochemically switched resulting in primary ion expulsion from the membrane and interfering ion uptake from the sample. Both approaches were tested for tetrabutylammonium‐selective electrodes. The approach's limitations are identified, which includes primary ions impurities in interfering ion salts and an interaction between primary ion and redox polymer. These limitations are visualized with ionophore‐based sodium‐ and silver‐selective electrodes.
Transient electrophoresis in a suspension of charged particles with arbitrary electric double layers
Authors: Lai Yi C. , Keh Huan J.
Published: January 2021

The startup of electrophoretic motion in a suspension of spherical colloidal particles, which may be charged with constant zeta potential or constant surface charge density, due to the sudden application of an electric field is analytically examined. The unsteady modified Stokes equation governing the fluid velocity field is solved with unit cell models. Explicit formulas for the transient electrophoretic velocity of the particle in a cell in the Laplace transforms are obtained as functions of relevant parameters. The transient electrophoretic mobility is a monotonic decreasing function of the particle‐to‐fluid density ratio and in general a decreasing function of the particle volume fraction, but it increases and decreases with a raise in the ratio of the particle radius to the Debye length for the particles with constant zeta potential and constant surface charge density, respectively. On the other hand, the relaxation time in the growth of the electrophoretic mobility increases substantially with an increase in the particle‐to‐fluid density ratio and with a decrease in the particle volume fraction but is not a sensitive function of the ratio of the particle radius to the Debye length. For specified values of the particle volume fraction and particle‐to‐fluid density ratio in a suspension, the relaxation times in the growth of the particle mobility in transient electrophoresis and transient sedimentation are equivalent.
Developing an adaptive neuro‐fuzzy inference system based on particle swarm optimization model for forecasting Cr(VI) removal by NiO nanoparticles
Authors: Rajabi Kuyakhi Hossein , Tahmasebi Boldaji Ramin
Published: January 2021

The treatment of wastewater from heavy metal ions such as hexavalent chromium Cr(VI) is considered as an important issue in recent years, which is harmful to human health and environment. Since, in engineering, performing the experiments to solve problems is time‐consuming and costly. In this study, adaptive neuro‐fuzzy inference system (ANFIS) was coupled with particle swarm optimization (PSO) algorithm to develop a predictive model for modeling of Cr(VI) removal percent on NiO nanoparticle. To this end, the trace of four initial parameters containing contact time, Cr(VI) initial concentration, NiO adsorbent dosage, and pH on removing Cr(VI) was investigated. The performance of the developed algorithm was evaluated by statistical parameters such as mean absolute relative deviation mean squared error (MSE) maximum absolute error and, R2 and graphic methods. The ANFIS‐PSO shows high‐performance modeling of Cr(VI) removal with R2 = 0.998, MSE = 0.0014, and AARD = 0.0011 compare to the established model in previous works.
Simultaneous adsorption of manganese and fluoride from aqueous solution via bimetal impregnated activated carbon derived from waste tire: Response surface method modeling approach
Authors: Bose Saswata , Mukherjee Tirthankar , Rahaman Mehabub
Published: January 2021

Adsorptive removal of manganese and fluoride from wastewater by waste tire‐derived activated carbon impregnated with iron and cobalt has been presented in this article. The surface properties of bimetallic activated carbon were characterized in scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET), and X‐ray diffraction (XRD). The newly developed adsorbent was used for simultaneous removal of fluoride and manganese from aqueous solution. Present work focuses on the optimization of process parameters using response surface method (RSM) technique employing significant parameters, namely, adsorbent dosage, initial fluoride and manganese concentrations, contact time and pH. Central composite design in RSM was utilized for the levels of adsorbent dosage (0.5–1 g/L), initial fluoride concentration (20–40 ppm), initial manganese concentration (30–50 ppm), time (15–35 min), and pH (4–8) of the solution. The R2 value obtained from the statistics data was 96.25 and 97.57% for fluoride and manganese, respectively. The optimal values were determined as the adsorbent dosage of 1.25 g/L, initial fluoride concentration of 10 ppm, initial manganese concentration of 25.25 ppm, the contact time of 30.9 min and pH of solution of 2.0, under which 99.96% manganese and 85.34% fluoride removal efficiency could be accomplished.
Communication systems of high‐speed railway: A survey
Authors: Gheth Waled , Rabie Khaled M. , Adebisi Bamidele , Ijaz Muhammad , Harris Georgina
Published: January 2021

Modern railway services are required to deliver good quality services to the passenger throughout the whole journey. These include improved performances, safety, and reduce delays. There is also the requirement for in‐train customer experience such as infotainment and access to reliable communication systems. The railway industry has employed different types and generations of communication systems in recent times. Signaling systems were used at the early stage of the railway services. Today, communication systems such as the second‐generation communication system, also known as the global system for mobile communications (GSM), the Third‐generation (3G) and the Fourth‐generation (4G) are utilized in the railway industry. In this paper, we present a brief history of railway communication systems, their features and applications. In addition, we discuss the technical challenges and potential solutions of in‐train communication systems and how data can be distributed on‐board and between the train coaches using state of the art and hybrid communication technologies.
In‐situ synthesis and adhesion method to prepare phosphorous–nitrogen compounds flame‐retardant wood pulp paper with high efficiency and durability
Authors: Zhang Yaowen , Bao Qiuru , Liu Yuan , Wen Hui , Wang Qi
Published: January 2021

In the present work, flame‐retardant wood pulp paper (WPP) with high water resistance was fabricated through in‐situ synthesis and adhesion of flame retardant on the lignocellulose fibers. Through a simple solution spraying method, melamine (Me) and polyphosphoric acid solution were adequately permeated into interior lignocellulose fibers of WPP in turn and then reacted to produce water‐insoluble phosphorous–nitrogen melamine polyphosphate (MPP). The finally sprayed melamine formaldehyde prepolymer played the roles of flame‐retardant coating, adhesive agent, and water‐proofing layer, thus bonding MPP particles to the lignocellulose fibers firmly. This low‐cost and efficient treatment endowed WPP with excellent flame retardance and satisfactory durability. It showed that the modified WPP had a high limiting oxygen index value of 37.3%, and achieved B‐0 rating in vertical burning test, as well as greatly lowered the peak heat release rate and the total heat release. The flame‐retardant mechanisms of the modified WPP were analyzed and discussed. Moreover, the flame retardance kept well after 72 hours of water resistance test, showing good combination between the flame‐retardant particles and the lignocellulose fibers.
Adaptive downstream tensorial eddy viscosity for hybrid large‐eddy simulations‐Reynolds‐averaged‐Navier–Stokes simulations
Authors: Zhang Wanjia , Shih Tom I‐P.
Published: January 2021

An adaptive method is developed to improve the accuracy of eddy‐viscosity Reynolds‐averaged‐Navier–Stokes (RANS) model in hybrid large‐eddy simulations (LES)‐RANS simulations by using available upstream LES results. The method first gets the tensorial eddy viscosity from the upstream LES solution at the LES‐RANS interface and then uses that information to improve the downstream RANS model by invoking the weak‐equilibrium assumption. The proposed method was evaluated via two test problems—flow in a channel and over a periodic hill. Results obtained show the proposed approach to increase the accuracy and stability of hybrid LES‐RANS simulations. Since the modification of the downstream RANS model is based on the tensorial eddy viscosity from the upstream LES solution, the method is adaptive to the problem being studied.
All Fish, All the Time: A Good General Objective for Fish Passage Projects?
Authors: Harvey Bret C , Railsback Steven F
Published: January 2021

Better understanding of the degree of “passability” needed to sustain robust sub-populations upstream of barriers could help address and perhaps eliminate perceived trade-offs between fish passage and other resource management goals. We used spatially explicit, individual-based modeling to explore the population-level consequences of various levels of upstream passability by (1) adult resident trout, and (2) juvenile salmon. In simulations of a stream network with widespread barriers, adult trout allowed to move upstream during only the highest 4% of streamflows sustained the distribution and abundance of the population to the same extent as in a no-barrier scenario. In simulations of salmon production in a reach fully accessible to spawning adults, the number of barriers to upstream movement by juvenile salmon did not affect the production of large outmigrants. Passage objectives less ambitious than “all the fish, all the time” may sometimes suffice to maintain populations of resident trout and anadromous salmon.
Qualitative analysis of the structural, thermal and rheological properties of a plant ice cream based on soy and sesame milks
Authors: Ghaderi Sajad , Mazaheri Tehrani Mostafa , Hesarinejad Mohammad Ali
Published: January 2021

The aim of this study was to investigate the structural, physicochemical, and rheological properties of soy and sesame milk‐based ice cream in order to optimize its formula. The overrun percentage of the optimized ice cream was acceptable compared to the conventional ice cream (produced with cow milk). The hardness and consistency of the optimized ice cream were significantly (p < .05) higher than those of the conventional one, while its cohesiveness was lower. All the samples showed the pseudoplastic behavior and the power‐law model had a high efficiency (R2 ≥ .99) in describing their rheological behavior. The lowest span value, the lowest mean particle diameter, and the highest mean particle surface area, and thus, the most stable and homogenous samples were associated with the conventional ice cream followed by the optimized plant one. The number of air bubbles in the structure of the conventional and optimized ice creams was significantly (p < .05) higher than in the other samples. The soy ice cream had the lowest Tg(−58.04°C), whereas the conventional one had the highest Tg(−55.05°C). Unlike the plant‐based samples, especially the soy ice cream, the conventional ice cream had the lowest ice content (IC), the highest unfreezable water (UFW), and the lowest frozen water (FW). Overall, this ice cream was more acceptable in terms of sensory attributes in comparison with the control sample and could be supplied to consumers as a novel, high‐quality, and marketable ice cream.
Investigating the properties of PLA‐nanochitosan composite films containing Ziziphora Clinopodioides essential oil and their impacts on oxidative spoilage of Oncorhynchus mykiss fillets
Authors: Shakour Nastaran , Khoshkhoo Zhaleh , Akhondzadeh Basti Afshin , Khanjari Ali , Mahasti Shotorbani Peyman
Published: January 2021

The present study aimed to investigate the impact of polylactic acid (PLA) integrated with nanochitosan (NC) composite film and Ziziphora Clinopodioides essential oil (ZCEO) on oxidative spoilage of rainbow trout fillets during a 9‐day refrigeration period. For this purpose, first, six degradable films including T1: PLA, T2: PLA + NC, T3: PLA + NC + 1% ZCEO, T4: PLA + NC + 1.5% ZCEO, T5: PLA + 1% ZCEO, and T6: PLA + 1.5% ZCEO were prepared. Next, the properties of the films were investigated. The results of the mechanical tests showed that ZCEO decreased the tensile strength and increased the elongation at the break of the PLA films. However, adding NC improved the mechanical characteristics of the PLA film. The outcomes of physical tests including moisture content (14.02%), solubility (17.41%), water vapor permeability (1.14 × 10−7 g s−1 m−1 Pa−1), and oxygen transmission rate (21.54 cm3.mm/m2.24 hr) showed that adding 1% ZCEO improved the film physical characteristics. Nevertheless, by adding 1.5% concentration EO to the PLA film, the values of water vapor permeability, porosity (according to the scanning electron microscopy), and turbidity increased and cross‐sectional pores were observed. Moreover, the films had high antioxidant properties (84.33%). In the next step, the effects of the mentioned films on the oxidative spoilage of rainbow trout fillets were investigated. The results of the chemical analysis in PLA film with the EO compared with the control treatment revealed the increasing trend of oxidation indices, in general. Moreover, increasing the concentration yielded better results such that all treatments containing EO showed satisfactory results up until the storage period ends. In most cases, adding NC affected the mentioned characteristics positively, and the best results were observed in T4 and then in T3. However, based on economics and the better mechanical and physical properties of T3, the film can be applied as an active packaging in fishery products.
Responsibly Sourced Gas: Time to Change the Natural Gas Industry's Narrative
Authors: Russo Thomas N.
Published: January 2021

The majority of companies in the natural gas and liquefied natural gas (LNG) industry seem fixated on promoting natural gas as the clean “bridge fuel” to further deployment of renewable energy technologies. While natural gas emits far less carbon dioxide (CO2)than coal or oil used to generate power and heat, it is still a “fossil fuel” that contributes to the adverse effects on climate. Fossil‐fuel opponents are increasingly skeptical of the climate benefits reported by the US natural gas and LNG industry. These opponents often cite a study released in April 2020 that showed methane emissions from the Permian basin of West Texas and New Mexico, one of the largest oil‐producing regions in the world, are more than two times higher than federal government estimates.
Chitosan‐Functionalized Recycled Polyethylene Terephthalate Nanofibrous Membrane for Sustainable On‐Demand Oil‐Water Separation
Authors: Baggio Andrea , Doan Hoan N. , Vo Phu P. , Kinashi Kenji , Sakai Wataru , Tsutsumi Naoto , Fuse Yasuro , Sangermano Marco
Published: January 2021

The preservation of marine ecosystems is one of the most severe challenges at present. In particular, oil‐water separation from oil spills and oily wastewater is important. For this reason, a low‐cost, effective, and sustainable polymeric solution is in high demand. In this work, a controlled‐wettability membrane for selective separation of oil‐water mixtures and emulsions is developed. The nanofibrous membrane is prepared via a facile and cost‐effective electrospinning technique using environmentally sustainable materials, such as recycled polyethylene terephthalate and chitosan. The effect of different concentrations of chitosan on the morphology, chemical composition, mechanical properties, wettability, and separation performance of the membrane is evaluated. The membranes exhibited underoil superhydrophobic and underwater superoleophobic behavior, which is essential to perform the selective separation. In fact, the designed filter has competitive antifouling properties (oil intrusion pressure > 45 kPa) and showed high heavy‐ and light‐oil/water separation efficiencies (>95%) both for emulsions and immiscible mixtures.
Spatial and temporal variability in geomorphic change at tidally influenced shipwreck sites: The use of time‐lapse multibeam data for the assessment of site formation processes
Authors: Majcher Jan , Quinn Rory , Plets Ruth , Coughlan Mark , McGonigle Christopher , Sacchetti Fabio , Westley Kieran
Published: January 2021

Shipwrecks are an integral part of our maritime archaeological landscape and are associated with diverse societal and cultural interests, yielding significant management challenges. Coupled hydrodynamic and geomorphological processes significantly impact the effective in situ preservation of these fragile sites. In this study, we assess sediment budget change and hydrodynamic triggers at metal‐hulled shipwrecks lost between 1875 and 1918, all located in the tidally dominated Irish Sea at depths between 26 and 84 m. This is conducted using time‐lapse, multibeam echosounder surveys at multiannual, annual, and weekly time steps, supported by sediment grain‐size analysis, modeled ocean currents, and shallow seismic data. Results indicate significant changes at all time steps for sites located in sand‐dominated environments, whereas the seabed around shipwrecks settled in multimodal sediments shows virtually no change outside of measurement errors (±30 cm). Variability in geomorphic change is attributed to local environmental factors, including bed shear stress, sediment supply, and spatial barriers to scour. We demonstrate that individual wrecks in similar shelf sea regions can be in very different equilibrium states, which has critical implications for the in situ management of underwater cultural heritage.
The Growing Burden of Disability Related to Chronic Liver Disease in the United States: Data From the Global Burden of Disease Study 2007-2017
Authors: Paik James M. , Golabi Pegah , Younossi Youssef , Saleh Nazaneen , Nhyira Annan , Younossi Zobair M.
Published: January 2021

Chronic liver disease (CLD) causes significant morbidity and mortality in the United States with regional variations. Comparable and consistent state-level measures of CLD-related morbidity and disability among U.S. states have not been well studied. Our aim was to assess the CLD burden within the United States between 2007 and 2017 based on the most common causes of CLD: hepatitis B virus, hepatitis C virus (HCV), alcoholic liver disease (ALD), and nonalcoholic fatty liver disease (NAFLD). The Global Burden of Disease database was used for the years 2007-2017. International Classification of Diseases, Tenth Revision, codes were used to identify liver cancer (LC) and cirrhosis. Disability-adjusted life years (DALYs) were computed by the summation of years of life lost and years lived with disability. All rates reported here were age-standardized rates per 100,000 population. In 2017, there were 167,324 incident CLDs, 21% from LC and 79% from cirrhosis; this number was 30% higher than in 2007. The highest rate increases were seen in Kentucky, New York, and Pennsylvania. In 2017, there were 90,046 CLD-related deaths, which was 34% higher than in 2007. Highest rank increases were seen in Kentucky, Montana, and Washington. The rate of CLD incidence and death due to NAFLD was higher than other causes of CLD. In 2017, CLD caused 2.33 million DALYs, which was 27% higher than in 2007 and was mainly driven by HCV (37.2%), ALD (27.7%), and NAFLD (10.6%). California, Texas, and Florida had the highest DALYs; however, the highest CLD-DALY rates per 100,000 population were seen in New Mexico, District of Columbia, and Oklahoma. Conclusion: The CLD-related burden is increasing in the majority of U.S. states at an unprecedented rate. The impact of this burden on individual states is heterogeneous, and there are important disparities among states that merit further investigation.