bluuebunny/crossref_metadata_2025 huggingface dataset:
Organic Moiety‐Regulated Photocatalytic Performance of Phosphomolybdate Hybrids for Hexavalent Chromium Reduction
Authors: Zhang Ya‐Qi , Hou Lin , Bi Hao‐Xue , Fang Xiao‐Xue , Ma Yuan‐Yuan , Han Zhan‐Gang
Published: April 2021

Visible‐light‐driven photocatalytic Cr(VI) reduction is a promising pathway to moderate environmental pollution, in which the development of photocatalysts is pivotal. Herein, three hourglass‐type phosphomolybdate‐based hybrids with the formula of: (H2bpe)3[Zn(H2PO4)][Zn(bpe)(H2O)2]H{Zn[P4Mo6O31H6]2} ⋅ 6H2O (1) Na6[H2bz]2[ZnNa4(H2O)5]{Zn [P4Mo6O31H3]2} ⋅ 2H2O (2) and (H2mbpy) {[Zn(mbpy)(H2O)]2[Zn(H2O)]2}{Zn[P4Mo6O31H6]2} ⋅ 10H2O (3) (bpe=trans‐1,2‐bi(4‐pyridyl)‐ethylene; bz=4,4′‐diaminobiphenyl; mbpy=4,4’‐dimethyl‐2,2’bipyridine) were synthesized under the guidance of the functional organic moiety modification strategy. Structural analysis showed that hybrids 1–3 have similar 2D layer‐like spatial arrangements constructed by {Zn[P4Mo6]2} clusters and organic components with different conjugated degree. With excellent redox properties and wide visible‐light absorption capacities, hybrids 1–3 display favourable photocatalytic activity for Cr(VI) reduction with 79%, 70% and 64% reduction rates, which are superior to that of only inorganic {Zn[P4Mo6]2} itself (21%). The investigation of organic components on photocatalytic performance of hybrids 1–3 suggested that the organic counter cations (bpe, bz and mbpy) can effectively affect the visible‐light absorption, as well as the recombination of photogenerated carriers stemmed from {Zn[P4Mo6]2} clusters, further promoting their photocatalytic performances towards Cr(VI) reduction. This work provides an experimental basis for the design of functionalized photocatalysts via the modification of organic species.
On optimal maintenance of degrading multistate systems with state‐dependent cost of repair
Authors: Finkelstein Maxim , Eryilmaz Serkan
Published: April 2021

This article considers an optimal maintenance policy for the multistate systems with the finite number of states. Each state is described by its level of performance ranging from the perfect one to the zero level for the state of failure. Moreover, we assume that the cost of preventive maintenance (PM; i.e., repair/rejuvenation in our case) also depends on the state of a system. Based on the proposed policy, the expected cost per unit of time is defined and the conditions for the existence of the unique and finite PM time are obtained in terms of dynamic reliability characteristics of the system. The results are applied to the three‐state Markovian system and a parallel system with n components. The latter is also discussed for the case of the positively dependent components.
The prevalence of the azygos lobe: A meta‐analysis of 1,033,083 subjects
Authors: Yurasakpong Laphatrada , Yammine Kaissar , Limpanuparb Taweetham , Janta Sirorat , Chaiyamoon Arada , Kruepunga Nutmethee , Meemon Krai , Suwannakhan Athikhun
Published: April 2021

The azygos lobe (AL) is an accessory lobe of the right lung with prevalence between 0.4 and 1.2%. The aim of the present review is to provide a better estimate of the frequency of the AL and to examine its relationships with other variables such as population, diagnostic methods, and co‐occurring illnesses. Studies published between 1899 and October 2020 were searched through three electronic databases; Google Scholar, PubMed, and JSTOR. Titles, abstracts, and full texts of the retrieved entries were screened to determine their appropriateness for inclusion. A total of 88 studies relating to 1,033,083 subjects met the inclusion criteria. A random‐effects meta‐analysis yielded an overall prevalence of 0.30% (95% CI: 0.0024–0.0035, I2 = 97.9%). Linear regression and subgroup analysis revealed a negative correlation (ρ = −0.540, p <0.001) between AL prevalence and sample size; studies with smaller sample sizes had higher prevalences. The AL prevalence in individuals with congenital pulmonary defects, 5.2% (95% CI: 0.0018–0.0086, I2 = 0%), was 17 times higher than the overall prevalence (z = 6.65, p <0.001), suggesting associations with other abnormalities and possibly a genetic predisposition. In addition to an evidence‐based synthesis of AL prevalence, this study demonstrates publication bias and small‐study effects in the anatomy literature. Awareness of the AL is crucial for radiologists when they interpret unusual radiological findings and for surgeons when they operate in the region.
Cyamella (a popliteal sesamoid bone) prevalence: A systematic review, meta‐analysis, and proposed classification system
Authors: Berthaume Michael A. , Bull Anthony M. J.
Published: April 2021

The cyamella is a rare, generally asymptomatic, knee sesamoid bone located in the proximal tendon of the popliteal muscle. Only two studies have investigated cyamella presence/absence in humans, putting ossified prevalence rates at 0.57%–1.8%. We aim to (a) determine cyamella prevalence in a Korean population, (b) examine coincident development of the cyamella and fabella, and (c) perform a systematic review and meta‐analysis on the cyamella in humans. Medical computed tomography scans of 106 individuals were reviewed. A systematic review and meta‐analysis were performed following PRISMA guidelines. Cyamellae were found in 3/212 knees (1.4%), and presence/absence was uncorrelated to height, age, and sex. The cyamella was not found coincidentally with the fabella, although the statistical power was low. Our systematic review/meta‐analysis revealed cyamellae were generally asymptomatic and ossification could occur at 14 years. Cyamellae were equally likely to be found in both sexes, knees, one or both knees, and there appeared to be no global variation in prevalence rates. Cyamellae were found in three distinct locations. There is little support for the role of intrinsic genetic and/or environmental factors in cyamella development in humans. However, the apparent phylogenetic signal in Primates suggests genetics plays a role in cyamella development. We propose a cyamella classification system based on cyamella location (Class I, popliteal sulcus; Class II, tibial condyle; Class III, fibular head) and hypothesize locations may correspond to distinct developmental pathways, and cyamella function may vary with location.
Patients with COVID‐19 who experience a myocardial infarction have complex coronary morphology and high in‐hospital mortality: Primary results of a nationwide angiographic study
Authors: Abizaid Alexandre , Campos Carlos M. , Guimarães Patrícia O. , Costa José de Ribamar , Falcão Breno A. A. , Mangione Fernanda , Caixeta Adriano , Lemos Pedro A. , de Brito Fabio S. , Cavalcante Ricardo , Bezerra Cristiano Guedes , Cortes Leandro , Ribeiro Henrique B. , de Souza Francis R. , Huemer Natassja , do Val Renata M. , Caramelli Bruno , Calderaro Daniela , Lima Felipe G. , Hajjar Ludhmila A. , Mehran Roxana , Filho Roberto Kalil ,   the COVID MI investigators
Published: April 2021

Objectives

We aimed to explore angiographic patterns and in‐hospital outcomes of patients with concomitant coronavirus disease‐19 (COVID‐19) and myocardial infarction (MI).

Background

Patients with COVID‐19 may experience MI during the course of the viral infection. However, this association is currently poorly understood.

Methods

This is a multicenter prospective study of consecutive patients with concomitant COVID‐19 and MI who underwent coronary angiography. Quantitative and qualitative coronary angiography were analyzed by two observers in an independent core lab.

Results

A total of 152 patients were included, of whom 142 (93.4%) had COVID‐19 diagnosis confirmation. The median time between symptom onset and hospital admission was 5 (1–10) days. A total of 83 (54.6%) patients presented with ST‐elevation MI. The median angiographic Syntax score was 16 (9.0–25.3) and 69.0% had multi‐vessel disease. At least one complex lesion was found in 73.0% of patients, 51.3% had a thrombus containing lesion, and 57.9% had myocardial blush grades 0/1. The overall in‐hospital mortality was 23.7%. ST‐segment elevation MI presentation and baseline myocardial blush grades 0 or 1 were independently associated with a higher risk of death (HR 2.75, 95%CI 1.30–5.80 and HR 3.73, 95%CI 1.61–8.61, respectively).

Conclusions

Patients who have a MI in the context of ongoing COVID‐19 mostly present complex coronary morphologies, implying a background of prior atherosclerotic disease superimposed on a thrombotic milieu. The in‐hospital prognosis is poor with a markedly high mortality, prompting further investigation to better clarify this newly described condition.
Highly Enhanced Methanol Electrooxidation on Pt/N−CNT‐Decorated FeP**
Authors: Liu Dongqin , Yang Guangxing , Zhang Qiao , Wang Hongjuan , Yu Hao , Peng Feng
Published: April 2021

The electrooxidation of methanol – the anodic reaction of direct methanol fuel cells – suffers from slow kinetics. Here, we report an enhanced current density for a Pt catalyst supported on nitrogen‐doped carbon nanotube (N−CNT) decorated FeP. X‐ray photoelectron spectra show that the introduction of FeP increases the binding energy of the Pt nanoparticles. The results show that Pt/FeP15%/N−CNT displays a 3.4 times higher forward peak current density compared to commercial Pt/C. The improved performance is attributed to a change in the electronic state of the Pt nanoparticles through the electronic interaction between Pt and FeP, evidenced by the mitigated CO poisoning.
Accessing C2‐Functionalized 1,3‐(Benz)azoles through Transition Metal‐Catalyzed C−H Activation
Authors: Basak Sumon , Dutta Subhabrata , Maiti Debabrata
Published: April 2021

The skeletal presence of 1,3‐azoles in a variety of bioactive natural products, pharmacophores, and organic materials demands the derivatization of such heteroarenes regioselectively. Plenty of cross‐coupling as well as cyclocondensation reactions have been performed to build up these skeletons but remained commercially unrealizable. A couple of severe drawbacks are faced by these traditional protocols that require a more straightforward strategy to obviate them. Transition metal‐catalyzed C−H functionalization has emerged as a superior alternative in that context. 1,3‐Azoles and their benzo counterparts have been extensively functionalized exploiting both noble and earth‐abundant transition metals. Lately, C‐2 functionalization have gained much traction due to the ease of attaining high regioselectivity and installation of synthetically manipulative functionalities. This critical review presents a bird‘s eye view of all major C‐2 functionalization of (benz)azoles catalyzed by a diverse set of metals performed over the past 15 years.
Scalable Production of Ambient Stable Hybrid Bismuth‐Based Materials: AACVD of Phenethylammonium Bismuth Iodide Films**
Authors: Wang M. , Sanchez‐Perez C. , Habib F. , Blunt M. O. , Carmalt C. J.
Published: April 2021

Large homogeneous and adherent coatings of phenethylammonium bismuth iodide were produced using the cost‐effective and scalable aerosol‐assisted chemical vapor deposition (AACVD) methodology. The film morphology was found to depend on the deposition conditions and substrates, resulting in different optical properties to those reported from their spin‐coated counterparts. Optoelectronic characterization revealed band bending effects occurring between the hybrid material and semiconducting substrates (TiO2 and FTO) due to heterojunction formation, and the optical bandgap of the hybrid material was calculated from UV‐visible and PL spectrometry to be 2.05 eV. Maximum values for hydrophobicity and crystallographic preferential orientation were observed for films deposited on FTO/glass substrates, closely followed by values from films deposited on TiO2/glass substrates.
Photoresponsive Binding Dynamics in High‐Affinity Cucurbit[8]uril‐Dithienylethene Host‐Guest Complexes
Authors: Colaço Miriam , Máximo Patrícia , Jorge Parola A. , Basílio Nuno
Published: April 2021

The use of external stimuli to control the binding kinetics in supramolecular systems is of critical importance for the development of advanced molecular machines and devices. In this work, a study focused on the kinetics of a water‐soluble host‐guest system based on cucurbit[8]uril and two dithienylethene (DTE) photoswitches is reported. It is shown that for the DTE guest comprising two anionic sulfonate side arms appended to pyridinium moieties, the formation/dissociation of the pseudorotaxane structures is slowed down by more than 100000‐fold with respect to its bipyridinium analogue. The decrease in ingression rate leads to the emergence of a competitive metastable product with the open DTE isomer that has an important influence in the overall binding kinetics. Moreover, the host‐guest dissociation kinetics is demonstrated to be approximately 100‐fold slower for the closed DTE isomer (t1/2=107 h vs. t1/2=1.2 h for the open isomer) allowing control over the dissociation rate with light.
Stereoretentive N‐Arylation of Amino Acid Esters with Cyclohexanones Utilizing a Continuous‐Flow System
Authors: Ichitsuka Tomohiro , Komatsuzaki Shingo , Masuda Koichiro , Koumura Nagatoshi , Sato Kazuhiko , Kobayashi Shū
Published: April 2021

The N‐arylation of chiral amino acid esters with minimal racemization is a challenging transformation because of the sensitivity of the α‐stereocenter. A versatile synthetic method was developed to prepare N‐arylated amino acid esters using cyclohexanones as aryl sources under continuous‐flow conditions. The designed flow system, which consists of a coil reactor and a packed‐bed reactor containing a Pd(OH)2/C catalyst, efficiently afforded the desired N‐arylated amino acids without significant racemization, accompanied by only small amounts of easily removable co‐products (i. e., H2O and alkanes). The efficiency and robustness of this method allowed for the continuous synthesis of the desired product in very high yield and enantiopurity with high space‐time yield (74.1 g L−1 h−1) and turnover frequency (5.9 h−1) for at least 3 days.
Multifunctional Polymer–Protein Conjugates Generated by Multicomponent Reactions†
Authors: Mao Tengfei , Zhu Chongyu , Tao Lei
Published: April 2021

Recently, multifunctional polymers for protein conjugation have been facilely synthesized through the multicomponent reactions (MCRs). In this mini‐review, current progress in the generation of multifunctional polymers with protein‐reactive groups via MCRs is summarized. These multifunctional polymers react with model therapeutic proteins, forming multifunctional polymer‐protein conjugates, which are prototypes of sophisticated theranostic agents and antibacterial vaccine candidates. In comparison with the traditional multi‐step synthesis, the preparation of multifunctional polymers for protein conjugation through MCRs is straightforward and convenient. Due to these properties, MCRs have the potential to become a new general strategy to achieve polymer‐protein conjugates for biological and medical applications.
Fundamental Aspects of Ceria Supported Au Catalysts Probed by In Situ/Operando Spectroscopy and TAP Reactor Studies
Authors: Abdel‐Mageed Ali M. , Chen Shilong , Fauth Corinna , Häring Thomas , Bansmann Joachim
Published: April 2021

The discovery of the activity of dispersed gold nanoparticles three decades ago paved the way for a new era in catalysis. The unusual behavior of these catalysts sparked many questions about their working mechanism. In particular, Au/CeO2 proved to be an efficient catalyst in several reactions such as CO oxidation, water gas shift, and CO2 reduction. Here, by employing findings from operando X‐ray absorption spectroscopy at the near and extended Au and Ce LIII energy edges, we focus on the fundamental aspects of highly active Au/CeO2 catalysts, mainly in the CO oxidation for understanding their complex structure‐reactivity relationship. These results were combined with findings from in situ diffuse reflectance FTIR and Raman spectroscopy, highlighting the changes of adlayer and ceria defects. For a comprehensive understanding, the spectroscopic findings will be supplemented by results of the dynamics of O2 activation obtained from Temporal Analysis of Products (TAP). Merging these results illuminates the complex relationship among the oxidation state, size of the Au nanoparticles, the redox properties of CeO2 support, and the dynamics of O2 activation.
How sowing date affects development and performance of safflower through climate variables
Authors: Franchini María Clara , Flemmer Andrea Cecilia , Lindström Lilia Ivone , Carrin María Elena , Constenla Diana , Johnson Richard Coburn
Published: April 2021

Safflower (Carthamus tinctorius L.) has unrealized potential as an alternative crop in many semiarid regions including central Argentina. Our objective was to relate how temperature and precipitation conditions with fall (5 June 2012 and 23 Apr. 2013) and winter sowing (13 Aug. 2012 and 20 Aug. 2013) affected phenology, yield, yield components, and oil percent in four winter and eight spring‐type safflower accessions in the semiarid region of central Argentina. Fall sowing was associated with lower temperatures, higher precipitation, lower heat/moisture stress indices and precipitation deficits than winter sowing. Rosette period lasted 55 d longer, and stem elongation to anthesis period 30 d longer in fall than in winter sowing. However, anthesis was advanced only few days in fall sowing and duration of postanthesis development was comparable between sowing regimes and years. Fall sowing plants averaged 3,252 filled grains m–2 and a grain yield of 109.8 g m–2, whereas winter sowing plants averaged 1,443 filled grains m–2 and a grain yield of 49.3 g m–2. Grain yield was 35% higher in winter than in spring‐type accessions, but winter types had lower oil percent (22.0%) than spring‐types (33.3%). In the semiarid region of central Argentina, we recommend fall sowing as it extended the growing season in terms of days preanthesis and presented favorable climatic conditions for safflower development.
Stabilizing LiNi0.8Co0.15Mn0.05O2 Cathode by Doping Sulfate for Lithium‐Ion Batteries
Authors: Li Jianying , Wu Jian , Li Shaomin , Liu Guobiao , Cui Yanhua , Dong Zhaohui , Liu Hao , Sun Xueliang
Published: April 2021

Residual sulfate (SO42−) in precursor Ni0.8Co0.15Mn0.05(OH)2 (pre‐NCM) is commonly regarded as being harmful to Li[Ni0.8Co0.15Mn0.05]O2 (NCM) performance, leading to significant performance losses and also hampering the electrode fabrication. Therefore, manufacturers try their best to lower sulfate contents in pre‐NCM. However, how the sulfate affects the cathode materials is not systematically studied. To address these issues, NCM was synthesized with different amounts of intentionally added sulfate (NH4)2SO4 in pre‐NCM. It was demonstrated that anionic SO42− doped in NCM could influence the grain size in sintering process and stabilize the layer structure during the charge–discharge process at a certain doping amount. The first‐principles calculations suggested that the SO42− doped in the transition metal layer could effectively facilitate Li+ diffusion in the lattice. SO42− doping could reduce the energy barrier for Li+ migration and then suppress drastic contraction of the c axis during cycling. The phase transition of H2 to H3 caused by c axis contraction was suppressed and the cycling performance was enhanced. The capacity retention could reach 80.9 (0.2 C) and 80.4 % (1 C) after 380 and 240 cycles in coin cells, respectively. These findings illustrate that a certain amount of sulfate could be beneficial to NCM cathodes.
Optimized localization using naked mole‐rat algorithm in dynamic wireless sensor networks
Authors: Singh Prabhjot , Singh Parulpreet , Mittal Nitin
Published: April 2021

Localization in wireless sensor networks (WSNs) becomes an essential and important part of research in past few years. Finding location of the occurring event is essential in most of the applications, namely, monitoring of objects, tracking of animals and various resources placed in the indoor and outdoor environments. WSN consists of sensors placed in huge amounts across large regions of globe to perform various tasks such as data sensing and communicating with other devices. The aim of this research is to analyse various location optimization techniques to address a WSN localization problem and assigning appropriate coordinates to the unknown sensor nodes. In this paper, the authors have introduced the concept of sensor node localization in a 2D dynamic environment using a single anchor node (static) along with virtual anchors to locate target nodes (dynamic) using hexagonal projection technique, and further, the estimated target node coordinates are optimized using novel naked mole‐rat algorithm (NMRA). This paper discusses the performance of various location optimization techniques available in literature with NMRA‐based technique in terms of localization error and number of localized nodes.
Application of a Tetraamino Cobalt(II) Phthalocyanine Modified Screen Printed Carbon Electrode for the Sensitive Electrochemical Determination of L‐Dopa in Pharmaceutical and Biological Samples
Authors: Georgescu State Ramona , Stefanov Cristina , van Staden Jacobus (Koos) Frederick , van Staden Raluca‐Ioana Stefan
Published: April 2021

A novel synthesized tetraamino cobalt(II) phthalocyanine monomer was used for the fabrication of a sensor by electrochemical polymerization. A disposable electrochemical sensor based on the use of a screen printed carbon electrode covered with an electropolymerized film of tetraamino cobalt(II) phthalocyanine for the determination of L‐dopa in pharmaceutical tablets and biological samples was described. Cyclic voltammetry and electrochemical impedance spectroscopy were performed for the characterization of the bare and modified electrode. For the electrochemical detection of L‐dopa differential pulse voltammetry was used. The proposed method exhibits a good response towards electrooxidation of L‐dopa in the linear concentration range: from 0.1 to 1000.0 μmol L−1 in BRB pH=2.0, with a detection limit of 0.03 μmol L−1 and from 1 to 1000 μmol L−1 in PBS pH=7.4, with a detection limit of 0.33 μmol L−1. Due to the fact that the developed sensor was applied in two different types of real samples, two buffer media were used, BRB pH=2.0 for pharmaceutical and urine samples and PBS pH=7.4 for whole blood samples. The proposed pCoTAPc/SPCE was successfully applied for the determination of L‐dopa in pharmaceutical tablets, urine and in whole blood samples with satisfactory results.
Determination of lipid–water partition coefficient of neutral and ionic drugs by liposome electrokinetic chromatography
Authors: Jiang Hui , Zhang Hao , Yin Shi‐Jun , Lu Min , Wang Xu , Yang Feng‐Qing
Published: April 2021

Profiling of lipid–water partition coefficients (KL/W) of drugs is an essential issue during the early stage of drug development. In this study, two liposomes, including 1,2‐distearoyl‐sn‐glycero‐3‐phosphocholine (DSPC) + cholesterol (Chol) (DSPC/Chol liposomes) and soybean lecithin (SPC) + Chol (SPC/Chol liposomes), were prepared for the liposome electrokinetic chromatography (LEKC) analysis, and the logarithm of lipid–water partition coefficients (log KL/W) of neutral and ionic drugs were determined based on an iterative method. The log KL/W values determined by the SPC/Chol or DSPC/Chol liposomes LEKC were linearly fitted, which showed a good fitting coefficient (R2 = 0.89). Furthermore, the linear relationship between the data obtained from LEKC system and octanol–water system, immobilized artificial membrane, Caco‐2 cell model, and software prediction was analyzed, respectively. Results illustrated that DSPC/Chol liposomes or SPC/Chol liposomes had a good linear relationship with Caco‐2 cell model, and R2 was 0.81 and 0.72, respectively. Moreover, the linear free energy relationship analysis suggested that the solute volume, hydrogen bond basicity, and J– were the main descriptors that drove the partition process of solutes in the SPC/Chol or DSPC/Chol LEKC system. In addition, the normalized properties of the SPC/Chol and DSPC/Chol LEKC systems through linear free energy relationship analysis were very close. In short, DSPC/Chol liposomes are more suitable for simulating cell membranes than SPC/Chol liposomes, and the developed LEKC is an effective partitioning model for measuring the log KL/W of drugs.
Chiral separation and molecular simulation study of six antihistamine agents on a coated cellulose tri‐(3,5‐dimethylphenycarbamate) column (Chiralcel OD‐RH) and its recognition mechanisms
Authors: Liu Yanru , Wang Xia , Yu Jia , Guo Xingjie
Published: April 2021

Enantiomeric separation of six antihistamine agents was first systematically investigated on a cellulose‐based chiral stationary phase (CSP), that is, cellulose tris‐(3,5‐dimethyl phenyl carbamate) (Chiralcel OD‐RH), under the reversed‐phase mode. Orphenadrine, meclizine, terfenadine, dioxopromethazine, and carbinoxamine enantiomers were completely separated under the optimized mobile phase conditions with resolutions of 5.02, 1.93, 1.68, 1.67, and 1.54, respectively. Mequitazine was partially separated with a resolution of 0.77. The influences of type and concentration of buffer salt, the pH of buffer solution, and the type and ratio of organic modifier on the chiral separation were evaluated and optimized. For a better insight into the enantiorecognition mechanisms, molecular docking was carried out via the Autodock software. The lowest binding energy and the optimal conformations of the analytes/CSP complexes were supplied, and the mechanisms of chiral recognition were determined. According to the results, the key interactions for the chiral recognition of these six analytes on CDMPC were π–π interactions, hydrophobic interactions, hydrogen bond interactions, and some special interactions.
A scalable parallel unstructured finite volume lattice Boltzmann method for three‐dimensional incompressible flow simulations
Authors: Xu Lei , Li Jingzhi , Chen Rongliang
Published: April 2021

The standard lattice Boltzmann method, which employs certain regular lattices coupled with discrete velocities as the computational grid, is limited in its flexibility to simulate flows in irregular geometries. To simulate large‐scale complex flows, we present a cell‐centered finite volume lattice Boltzmann method for incompressible flows on three‐dimensional (3D) unstructured grids and its corresponding parallel algorithm. The advective fluxes are calculated by the low‐diffusion Roe scheme, and the gradients of the particle distribution functions are computed with a least squares method. The presented scheme is validated by three benchmark flows: (a) a 3D Poiseuille flow, (b) cubic cavity flows with Reynolds numbers Re = 100 and 400, and (c) flows past a sphere with Re = 50, 100, 150, 200, and 250. Some parallel performance results are presented to show the scalability of the method, which reveal that the proposed parallel algorithm has considerable scalability and that the parallel efficiency is higher than 87% on 3840 processor cores. It can be seen that the presented parallel solver has significant potential for the accurate simulation of flows in complex 3D geometries.
Geochronological, geochemical, and Sr–Nd–Pb–Hf isotopes of Cretaceous gneissic granite and quartz monzonite in the Tongbai Complex: Record of lower crust thickening beneath the Tongbai orogen
Authors: Niu Pan‐Pan , Jiang Shao‐Yong
Published: April 2021

A comprehensive study of zircon U–Pb ages, major and trace elements, whole‐rock Sr–Nd–Pb isotopes and zircon Hf isotopes of the gneissic granite and quartz monzonite in the Tongbai Complex is conducted in an attempt to unravel their petrogenesis and shed new light on the tectonic evolution and crust thickening process of the Tongbai orogen. Zircon U–Pb dating indicates that the emplacement of gneissic granite was early at 144.2 ± 1.3 Ma, whereas the quartz monzonite formed later at 130.2 ± 1.7 Ma. Both the gneissic granite and quartz monzonite samples share many chemical similarities, such as high Al2O3, K2O, Sr contents and low MgO contents, together with high Sr/Y, high La/Yb ratios, suggesting an C‐adakitic affinity and possibly derived from partial melting of the thickened lower crust. The later quartz monzonites may have involvement of much more proportion of mantle‐derived materials (such as the metamorphosed mafic rocks, ecologite) in the lower crust during partial melting for its petrogenesis, due to its higher MgO, Cr, Ni, and V contents than the gneissic granites. The formation of the gneissic granite and quartz monzonite records the evolution history for the lower crust thickening beneath the Tongbai orogen at the Cretaceous. Nearly all granitoids in the Tongbai orogen currently found have an emplacement age of >130 Ma and have higher Sr/Y ratios and lower MgO, Cr, Ni, and V contents with respect to the granitoids in the Dabie orogen which occurs in two stages of granitic magmatism of >130 Ma and <130 Ma. The Tongbai orogen lacks the granitoids formed by significant crust–mantle mixing that occurred in the Dabei area at <130 Ma. These results indicate that the lower crust was continuing thickening but probably not delaminated beneath the Tongbai orogeny during the Early Cretaceous.
Frailty, post‐operative delirium and functional status at discharge in patients with hip fracture
Authors: Gandossi Chiara Maria , Zambon Antonella , Oliveri Giulia , Codognola Martina , Szabo Hajnalka , Cazzulani Ilaria , Ferrara Maria Cristina , Mottadelli Chiara , Galeazzi Marianna , Amoroso Isabella , Zarcone Cristina , Principato Giulia , Corsi Maurizio , Mazzola Paolo , Zatti Giovanni , Foti Giuseppe , Bellelli Giuseppe
Published: April 2021

Objective

To explore the effect of frailty, alone and in combination with post‐operative delirium (POD), on the risk of poor function at discharge in patients with hip fracture (HF).

Methods

This is a prospective cohort study of patients with HF admitted to an Orthogeriatric Unit (OGU) between October 1, 2011 and March 15, 2019. POD was assessed using the 4AT and the Diagnostic and Statistical Manual of Mental Disorders (DSM) 5‐edition criteria. A 22‐items Frailty Index (FI) was created using the data collected on admission. The outcome measure was the Cumulated Ambulation Score (CAS) score at discharge. A log‐binomial regression model was used to assess the effect of frailty and POD on CAS.

Results

A total of 988 patients (median age = 84.9 years, Interquartile range = 80.6‐89.2) were included: 360 patients (36.4%) were frail and 411 (42%) developed POD. Poor functional status at discharge (CAS score ≤2) was more common in frail than non‐frail patients (68.3% vs. 53.8%, p < 0.001) In a regression adjusted for confounders, frailty alone (Relative Risk, RR = 1.33, 95% Confidence Intervals, CI = 1.14–1.55) and POD alone (RR 1.38, 95% CI = 1.2–1.59) were associated with poor functional status at discharge; when combined, frailty and POD had an interaction, yielding a mild increase in the risk of poor outcome (RR 1.47, 95% CI = 1.28–1.69).

Conclusions

In older patients undergoing HF surgery, frailty, POD and their combination, are associated with poor functional status at discharge.
Identifying the optimal candidates for locoregional radiation therapy in patients with de novo metastatic nasopharyngeal carcinoma
Authors: Xu Hanchuan , Lu Lihu , Lu Tianzhu , Xu Yun , Zong Jingfeng , Huang Chaobin , Lin Fengjie , Zheng Yahan , Lin Cheng , Lin Senan , Qiu Sufang , Pan Jianji , Lin Shaojun , Guo Qiaojuan
Published: April 2021

Background

To evaluate the value of locoregional radiation therapy (LRRT) in de novo metastatic nasopharyngeal carcinoma (mNPC) and identify suitable candidates for additional LRRT after palliative chemotherapy (PCT).

Methods

Patients with de novo mNPC received platinum‐based chemotherapy for a minimum of four cycles with or without definitive LRRT via intensity‐modulated radiation therapy (IMRT) were all candidates for this study.

Results

A total of 168 patients were included for this analysis. Additional LRRT was associated with significantly longer median OS (69.5 vs. 17.8 months, p < 0.001) when compared with PCT alone. However, this survival benefit of LRRT was only reflected in patients with oligometastatic diseases (90.8 vs. 17 months, p < 0.001), but not for those with polymetastatic disease (p = 0.86).

Conclusions

Additional LRRT after PCT may only improve OS for oligometastatic patients. For patients with polymetastatic disease, intensive systemic treatment such as the combination of immunotherapy and adequate PCT might be necessary.
Internet of medical things embedding deep learning with data augmentation for mammogram density classification
Authors: Sadad Tariq , Khan Amjad Rehman , Hussain Ayyaz , Tariq Usman , Fati Suliman Mohamed , Bahaj Saeed Ali , Munir Asim
Published: April 2021

Females are approximately half of the total population worldwide, and most of them are victims of breast cancer (BC). Computer‐aided diagnosis (CAD) frameworks can help radiologists to find breast density (BD), which further helps in BC detection precisely. This research detects BD automatically using mammogram images based on Internet of Medical Things (IoMT) supported devices. Two pretrained deep convolutional neural network models called DenseNet201 and ResNet50 were applied through a transfer learning approach. A total of 322 mammogram images containing 106 fatty, 112 dense, and 104 glandular cases were obtained from the Mammogram Image Analysis Society dataset. The pruning out irrelevant regions and enhancing target regions is performed in preprocessing. The overall classification accuracy of the BD task is performed and accomplished 90.47% through DensNet201 model. Such a framework is beneficial in identifying BD more rapidly to assist radiologists and patients without delay.
A new focus measure operator for enhancing image focus in 3D shape recovery
Authors: Jang Hoon‐Seok , Yun Guhnoo , Mutahira Husna , Muhammad Mannan Saeed
Published: April 2021

Measuring the image focus is an important issue in Shape from Focus methods. Conventionally, the Sum of Modified Laplacian, Gray Level Variance (GLV), and Tenengrad techniques have been used frequently among various focus measure operators for estimating the focus levels in a sequence of images. However, they have various issues such as fixed window size and suboptimal focus quality. To solve these problems, a new focus measure operator based on the adaptive sum of weighted modified Laplacian is proposed. First, the adaptive window size selection algorithm based on the GLV is applied. Next, appropriate weights are assigned to the Modified Laplacian values in the image window based on the distance between the center pixel and neighboring pixels. Finally, the Weighted Modified Laplacian values in the image window are summed. Experimental results demonstrate the effectiveness of the proposed method.
Seed morphometry and ultrastructure studies on some Turkish orchids (Orchidaceae)
Authors: Süngü Şeker Şenay , Akbulut Mustafa Kemal , Şenel Gülcan
Published: April 2021

Orchid seeds have great morphological variations that imply the phylogenetic relationship of the species depending on the biodiversity of the family or act as an adaptation to seed dispersal mechanisms depending on the life form. This study aims to both describe and analyse the qualitative and quantitative traits of 12 Turkish orchids representing epidendroids and orchidoids in detail to investigate which properties are diagnostic among these taxa and also reveal if seed properties are differentiated in relationship to the ecological preferences of the studied species. Both qualitative and quantitative features were determined, and measurements were obtained using light and scanning electron microscopy. We applied the unweighted pair group method with arithmetic mean (UPGMA) cluster analysis and canonical discriminant analysis to the qualitative and quantitative traits. Furthermore, we analyzed the same orchid seed in correlation with ecological traits such as habitats and the elevation preferences of species. This study confirmed the usefulness of both data sets for effectively assessing the variation of orchid seeds. Although the seed characters such as the cell shape differences in the chalazal or medial region, seed sizes, cell numbers on the longitudinal axis, and periclinal wall ornamentation are taxonomically conserved, some other characteristics such as seed shape, the absence of periclinal wall ornamentation, and larger embryo size imply ecological adaptation or developmental achievement for germination. This study confirms the diagnostic value of both qualitative and quantitative seed features, which are effective in explaining the orchid seed variety.
Screening fertilizers for their phosphorus runoff risk using laboratory methods
Authors: da Silva Rodrigo C. , Degryse Fien , Baird Roslyn , Mallarino Antonio P. , McLaughlin Michael J.
Published: April 2021

Losses of phosphorus (P) from fertilized fields may result in degradation of water quality. Various initiatives are under evaluation to minimize water contamination, including the adoption of less soluble or coated P fertilizer formulations aiming to mitigate losses of P in runoff. Field‐based rainfall simulators are traditionally used to evaluate P runoff, but using these is time consuming, labor intensive, and costly given the complex apparatus and analyses involved. We hypothesized that laboratory‐based methods could be useful to evaluate the risk of P runoff from fertilizers. In order to identify a rapid, inexpensive, and efficient screening process, we compared two laboratory‐scale measurements, one in water (based on electrical conductivity measurements) and one in soil (based on visualization of P diffusion in soil), with runoff results from field‐, glasshouse‐, and laboratory‐based rainfall simulators, using coated soluble phosphate fertilizers. The laboratory‐based methods assessing the P release rate in water and in soil correlated closely (r ≥ .96) with the losses of P obtained in the three rainfall simulators regardless of the type of coating or solubility of the fertilizer. The faster and inexpensive electrical conductivity and diffusion visualization methodologies were useful to rank the fertilizers by P release to runoff. Hence, these tools may be useful for screening fertilizer formulations with respect to their runoff risk.
A new framework for the identification of flash drought: Multivariable and probabilistic statistic perspectives
Authors: Hu Chen , Xia Jun , She Dunxian , Li Lingcheng , Song Zhihong , Hong Si
Published: April 2021

Flash drought is distinguished with seasonal drought by its characteristics of sudden onset and rapid intensification, and has attracted increasing concern due to the severe negative impacts on socioeconomic development and ecosystems. To accurate identify the onset time and propagation of flash drought is still a big challenge, as it is influenced by many factors (e.g., deficit in precipitation, increase in evapotranspiration and temperature, shortage in soil moisture, and etc.). This study aims to develop a probabilistic and multivariable flash drought identification method (PMFDI) from the perspective of considering the interaction effects from different driving factors on flash drought occurrence and propagation with a multivariable statistical tool. The PMFDI uses the weekly standardized precipitation evapotranspiration index and the standardized soil moisture index to describe the abnormally changes in multiple hydrometeorological variables over a short duration. The linearly multivariable index (LMI) is employed to describe the correlation relationship between multiple hydrometeorological variables and to identify flash droughts from the aspects of sudden onset and rapid intensification. We select the Loess Plateau (LP) in China to verify the efficiency of the developed PMFDI with the comparison to the other two recently proposed flash drought identification methods. The results indicate that PMFDI can identify high‐ and low‐ frequency regions similar to those identified by the other two methods and can generally recognize actual flash droughts. In addition, the PMFDI can capture the comprehensive impact of multiple hydrometeorological variables as well as their interaction on flash drought occurrence, which provides a useful perspective to understand the propagation processes of the actual flash droughts in the LP.
The Effect of the Sequence of Creative Processes on the Quality of the Ideas: The Benefit of a Simultaneous Focus on Originality and Feasibility
Authors: Baruah Jonali , Paulus Paul B. , Kohn Nicholas W.
Published: April 2021

A major challenge in the process of innovation is to generate quality products that are original as well as feasible, because these features are associated with contradictory cognitive thought processes. This study investigated whether opportunities to engage in an idea generation, selection, and subsequent refinement with a simultaneous focus on originality and feasibility would enhance innovation. Experiment 1 examined whether a linear focus or a simultaneous focus on feasibility and originality in the process of first generating ideas and then refining them enhanced the overall quality of ideas. The simultaneous focus resulted in the highest originality and elaboration of ideas. Experiment 2 involved four stages of innovation—generation, selection, and two refinement phases—with a varied order of focus in the two refinement phases. Consistent with a dialectical approach to creativity, an iterative focus on feasibility and originality in the refinement phase was most beneficial in enhancing the quality of the ideas. The extent of idea elaboration played a mediation role in the development of ideas during the refinement phase of innovation.
Effects of salt concentration on the quality of paocai, a fermented vegetable product from China
Authors: Wang Xinyi , Song Ge , He Zhen , Zhao Mingwei , Cao Xinying , Lin Xinping , Ji Chaofan , Zhang Sufang , Liang Huipeng
Published: April 2021

BACKGROUND

Paocai is a traditional Chinese fermented vegetable food. As the most important ingredient, salt has crucial effects on the bacterial community and volatile compounds of paocai. To demonstrate the effects of salt on the fermentation of paocai, the bacterial composition and volatile compounds were investigated using high‐throughput sequencing and gas chromatography–mass spectrometry (GC–MS).

RESULTS

The salt had no significant effects on the bacterial community at the phylum level. Proteobacteria and Bacteroidetes gradually decreased during the fermentation, and Firmicutes gradually increased as the dominant bacteria in the late stage of fermentation. At the genus level, Lactobacillus and Lactococcus gradually increased in relative abundance during the fermentation and became the dominant bacteria in paocai. High salt levels can contribute to the growth of Lactobacillus, which became the dominant genus in paocai. The salt concentration affected the profiles of volatile compounds in paocai after fermentation. A total of 42 volatile components were detected by GC–MS, among which phenols, aldehydes, and nitriles were the main ones. A high salt concentration will increase the volatile compound content, mainly aldehydes and alcohols, and improve the flavor of paocai. At the same time, the electronic tongue analysis also showed that a high salt concentration made a major contribution to the flavor of paocai.

CONCLUSIONS

These data are helpful to elucidate the effects of salt on the quality of paocai and contribute to improving the quality and reducing the use of salt. © 2021 Society of Chemical Industry.
Cultivating destination brand ambassadors in rural China: Examining the role of residents' welcoming nature
Authors: Wang Haihong , Xiong Lina , Gage Rick
Published: April 2021

Consistent with growing research interest in local residents' roles and resident‐tourist relationship in destination marketing and branding, this study examines how residents' welcoming nature affects their destination brand advocacy and brand‐consistent behaviors in a rural destination in China. Focusing on destination branding in rural China and drawing upon internal branding literature, this study further examines how resident perceived interaction quality with tourists transforms their welcoming nature into destination brand‐supporting behaviors. Findings offer strong empirical results that highlight a critical internal branding perspective for mobilizing residents to support the destination brand. This study offers further theoretical and practical insights to an internally driven approach that cultivates destination brand ambassadors.
Molecular Polymer Brushes Made via Ring‐Opening Metathesis Polymerization from Cleavable RAFT Macromonomers
Authors: Gegenhuber Thomas , Müllner Markus
Published: April 2021

The use of labile covalent bonds such as oximes and acetals for their application in the synthesis, and controlled triggered deconstruction, of molecular polymer brushes (MPBs) is reported. Macromonomers (MMs) are produced via reversible addition‐fragmentation chain transfer (RAFT) polymerization using chain transfer agents (CTAs) featuring customized labile moieties. Ring‐opening metathesis polymerization (ROMP) of the MMs using the grafting‐through approach produced MPBs in which the cleavable CTA is incorporated along the backbone, between the brush mainchain and its side chains. Degradation (i.e., the detachment of side chains) of the brush is possible through exposure to an acid stimulus. Especially, ketoxime, solketal, and ethoxyethyl (EE) acetal‐based motifs demonstrate excellent orthogonality to the polymerization protocols. This study highlights how polymer architectures can be built from, and reverted to, single polymer chains by using well‐designed CTAs in a straight‐forward approach.
Theoretical investigation of the impact of different timing schemes in hypofractionated radiotherapy
Authors: Stavrev Pavel V. , Stavreva Nadejda , Ruggieri Ruggero , Nahum Alan E. , Tsonev Pavlin , Penev Dimitar , Pressyanov Dobromir
Published: April 2021

Purpose

This study compares the effectiveness of three fractionation schemes of equal fraction size, comprising five fractions of SBRT over 5 days, 10 days, or 15 days, respectively.

Method

This comparative study is based on two tumor‐control‐probability (TCP) models that take into account tumor cell re‐sensitization and repopulation during treatment; the Zaider‐Minerbo‐Stavreva (ZMS) and the Ruggieri‐Nahum (RN) models. The ZMS model is further modified to include also re‐sensitization according to the β mechanism of the linear‐quadratic (LQ) model of cell killing. The modified version of the ZMS model is verified through fitting to the experimental data set of Fisher and Moulder. The study applies an idea used in a plan ranking methodology developed for the case when the specific values of the model parameters are not known.

Results

The TCPs of the compared regimens are calculated for various values of the model parameters and for two different values of the dose per fraction. The TCPs are presented as 2‐D functions of two of the model parameters for each model correspondingly. The differences between the TCPs of each of the prolonged regimens and the TCP of the every week day regimen are also calculated for each model.

Conclusions

Both models predict that the prolonged regimens are superior in terms of TCP to the every week‐day one for most of the studied cases; however this is shown to exist to a different degree by the two models. It is shown again to a different degree that reversed situations where the every week day schedule is better than the prolonged regimens are also possible. It is concluded that a 30% TCP difference observed in a clinical study in favor of the fifteen‐day regimen is theoretically possible. However, the fifteen‐day regimen is outperformed in terms of TCP by the every week day regimen in more cases than the regimen lasting ten days. Therefore the choice of a prolongation in time must be made with care.