bluuebunny/crossref_metadata_2025 huggingface dataset:
Properties and mechanism of a poly(ionic liquid) inhibitor contained bi‐functional groups for bentonite hydration
Authors: Wang Hao , Gao Yihang , Jia Xuhong , Liu Quanyi
Published: June 2021

Present polymer inhibitors depend on a major inhibitory group to restrain bentonite hydration, and monomer design is concerned to improve the inhibition and stability through complex copolymerization. Conveniently, a homopolymer (PIL‐NH2) that contained primary amine and cationic imidazolium as bi‐functional groups was proposed, aiming to provide two synergistic inhibitory modes. Comprehensive methods were conducted to characterize the chemical structure and inhibitory performance of PIL‐NH2. The ζ potential absolute value of bentonite suspension was decreased by PIL‐NH2 from 28.7–33.3 mV to 4–7 mV, and the increment of bentonite particle size d50 was observable from 1.83892 μm to over 200 μm. With water squeezed out, the lattice spacing d001 of hydrated bentonite was reduced from 1.9070 to 1.2683 nm due to PIL‐NH2 intercalation. The ESEM images revealed that inhibited bentonite showed a tight structure with classical dehydration phenomenon, and the hydrogen bond between PIL‐NH2 and bentonite was further confirmed according to the FT‐IR result. In mechanism analysis, the electrostatic attraction and hydrogen bond existed simultaneously for PIL‐NH2 to adsorb bentonite. The two adsorption modes from bi‐functional groups were synergistic to improve inhibition remarkably. PIL‐NH2 maintained high performance during the whole hydration process, including crystalline hydration, osmotic hydration, and hydrated dispersion.
Profiling pharmacokinetics of double‐negative T cells and cytokines via a single intravenous administration in NSG mice
Authors: Xu Shangzhi , Ge Xinyu , Wang Liuyang , Tao Yimin , Tang Dongmei , Deng Xiaojie , Yang Fei , Zhang Qian , Qi Xinming , Gong Likun , Yang Liming
Published: June 2021

This study was intended to delineate the profile of double‐negative T cells (DNTs) in NOD.Cg‐Prkdcscid Il2rgtm1wj/SzJ mice and cytokines released from DNTs in vivo and in vitro. Total 4 × 107 cells of RC1012 injection per mice were intravenously infused. IFN‐γ, TNF‐α, IL‐1β, IL‐2, IL‐4, IL‐6, IL‐10 were measured in vivo and in vitro. A quantitative polymerase chain reaction (PCR) was employed to determine the gene copies of Notch2‐NLA per DNT cell from collected organs. Cytokines were significantly increased in vitro (4 h) and in vivo (3 h). DNT cells were distributed into the lung, liver, heart, and kidney earlier, and redistributed to lymphocyte homing spleen and bone marrow, which seemed to frame a two‐compartment pharmacokinetics (PK) model but more data are needed to confirm this, and the clearance of DNT cells fell into first‐order kinetics.
Chile’s enduring educational segregation: A trend unchanged by different cycles of reform
Authors: Gutiérrez Gabriel , Carrasco Alejandro
Published: June 2021

Socioeconomic segregation continues to be a central issue for education systems in which market‐driven reforms have been implemented. This study analyses trends of socioeconomic segregation in Chile (1999–2018), considering a period with an absence of policies aimed at reducing segregation (1999–2007) and a later stage (2008–2015) when measures were implemented with the potential to affect the socioeconomic composition of schools. Results show that the segregation of both disadvantaged and wealthy students increased to extremely high levels during the first period, and has not shown signs of any significant decrease since then. The slight reduction observed in the second period is associated with changes regarding school fees in the private subsidised education sector rather than the selectivity status of the schools. The challenges faced in fostering greater socioeconomic integration within a market‐driven educational system are discussed in this article.
Synthesis of gem‐Dichlorocyclopropanes Using Liquid–Liquid Slug Flow
Authors: Lee Jong Won , Jang Yea Seul , Park Jong Min , Park Chan Pil
Published: June 2021

By analyzing the causes of precipitation and clogging in continuous flow dichlorocyclopropanation, we established that the flow reaction can be performed only with T‐junctions and microtubes. Unlike tertiary amines, when quaternary ammonium salts were used as PTCs, precipitation and clogging in microchannels did not occur, and an excellent yield of up to 99% was obtained after optimizing the reaction temperature, reactant concentration, and retention time. In the scale‐up experiment, the reaction yields slightly decreased as the inner diameter (ID) of the microchannel was increased, but the calculated throughput increased from 2.41 g/h (ID: 1.5 mm) to 3.46 g/h (ID: 1.9 mm) and 5.13 g/h (ID: 2.4 mm)
Preparative separation of six compounds from Salvia yunnanensis Radix using pH‐zone‐refining counter‐current chromatography
Authors: Ma Tianyu , Wang Xinming , Li Lili , Wang Xiao , Guo Lanping , Liu Wei
Published: June 2021

Phenolic acids are the main active components in Salvia yunnanensis Radix, which have significant effects such as cardiovascular protection, anti‐thrombosis, anti‐oxidant, and anti‐inflammation. In this study, pH‐zone‐refining counter‐current chromatography (pH‐ZRCCC) was successfully applied to the preparative separation of phenolic acids from S. yunnanensis Radix. First, a two‐phase solvent system composed of Pet–EtOAc–ACN–H2O (1.5:2.5:1:5, v/v) [TFA (10 mM) was added in the upper phase and NH3·H2O (30 mM) was added in the lower phase] was used for the separation of 4.0 g of the crude sample to obtain 55.6 mg of rosmarinic acid (1), 69.0 mg of caffeic acid (2), 18.9 mg of protocatechualdehyde (3), 14.6 mg of 8‐epiblechnic acid 9‐methyl ester (4), and a mixture containing two compounds. After the recovery, 1.3 g of the mixture was obtained and separated using the MtBE–H2O (1:1, v/v) solvent system containing TFA (5 mM) and NH3·H2O (60 mM) to obtain 259.9 mg of salvianolic acid B (5) and 28.75 mg of lithospermic acid (6). Moreover, a systematic separation pattern for separating the relatively low‐polarity phenolic acids from natural products by pH‐ZRCCC was summarized for the first time. This study provided technical support for the pharmacological activity and quality control research of S. yunnanensis Radix.
Prosociality during COVID‐19: Globally focussed solidarity brings greater benefits than nationally focussed solidarity
Authors: Zagefka Hanna
Published: June 2021

Many charities are appealing for donations to address problems caused by the COVID‐19 crisis. Two survey studies (totalN = 500) tested predictors of donation intentions of British participants to help those suffering from the crisis in Britain (ingroup donations) and overseas (outgroup donations). Perceptions of international, global common fate in our success in managing and overcoming the crisis was positively associated with prosocial intentions towards both national ingroup and outgroup targets. In contrast, a desire to ‘close ranks’ within the national ingroup in the face of the pandemic threat was associated with more prosocial intentions towards national ingroup targets only, but it was associated withfewerprosocial intentions towards outgroup targets. This suggests that a focus on global solidarity (in the form of global common fate and identification with all humans) has positive effects on helping both within and across group boundaries, whereas a focus on national solidarity (in the form of ‘closing ranks’ in the face of the pandemic threat) has positive effects on helping within the national group but negative effects on prosocial tendencies towards outgroup members. The effect of perceived global common fate on both ingroup and outgroup helping was mediated by identification with all of humanity. Findings are discussed in terms of practical implications for managing the COVID‐19 crisis. Please refer to the Supplementary Material section to find this article'sCommunity and Social Impact Statement.
Prognostic impact of echocardiographic mean transvalvular gradients in patients with aortic stenosis and low flow undergoing transcatheter aortic valve implantation
Authors: Fischer‐Rasokat Ulrich , Renker Matthias , Liebetrau Christoph , Weferling Maren , Rolf Andreas , Doss Mirko , Hamm Christian W. , Kim Won‐Keun
Published: June 2021

Background

Blunted left ventricular hemodynamics reflected by a low stroke volume index (SVI) ≤35 mL/m2 body surface area (low flow [LF]) in patients with severe aortic stenosis (AS) are associated with worse outcomes even after correction of afterload by transcatheter aortic valve implantation (TAVI). These patients can have a low or high transvalvular mean pressure gradient (MPG). We investigated the impact of the pre‐interventional MPG on outcomes after TAVI.

Methods

Patients with LF AS were classified into those with normal (EF ≥ 50%; LF/NEF) or reduced ejection fraction (EF < 50%; LF/REF) and were then stratified according to an MPG < or ≥ 40 mmHg. Patients with SVI >35 mL/m2 (normal flow; NF) served as controls.

Results

597 patients with LF/NEF, 264 patients with LF/REF and 975 patients with NF were identified. Among all groups those patients with a low MPG were characterized by higher cardiovascular risk. In patients with LF/REF, functional improvement post‐TAVI was less pronounced in low‐MPG patients. One‐year survival was significantly worse in LF AS patients with a low vs. high MPG (LF/NEF 16.5% vs. 10.5%, p = 0.022; LF/REF 25.4% vs. 8.0%, p = 0.002), whereas no differences were found in NF patients (8.7% vs. 10.0%, p = 0.550). In both LF AS groups, a low pre‐procedural MPG emerged as an independent predictor of mortality.

Conclusions

In patients with LF AS, an MPG cut‐off of 40 mmHg defines two patient populations with fundamental differences in outcomes after TAVI. Patients with LF AS and a high MPG have the same favorable prognosis as patients with NF AS.
Ruthenium‐Catalyzed Deuteration of Aromatic Carbonyl Compounds with a Catalytic Transient Directing Group
Authors: Kopf Sara , Ye Fei , Neumann Helfried , Beller Matthias
Published: June 2021

Invited for the cover of this issue are Helfried Neumann, Matthias Beller and co‐workers at the Leibniz‐Institut für Katalyse e. V., Rostock and Hangzhou Normal University. The image depicts “the case of ketone deuteration” being solved by Sherlock Holmes. Read the full text of the article at 10.1002/chem.202100468.
Acylhydrazone Subunits as a Proton Cargo Delivery System in 7‐Hydroxyquinoline
Authors: Nakashima Kosuke , Petek Anton , Hori Yutaro , Georgiev Anton , Hirashima Shin‐ichi , Matsushima Yasuyuki , Yordanov Dancho , Miura Tsuyoshi , Antonov Liudmil
Published: June 2021

The reimagined concept of long‐range tautomeric proton transfer using crane subunits is shown by designing and synthesising two new acylhydrazones containing a 7‐hydroxyquinoline (7‐OHQ) platform. The acylhydrazone subunits attached to the 7‐OHQ at the 8th position act as crane arms for delivering proton cargo to the quinoline nitrogen. Light‐induced tautomerization to their keto forms leads to Z/E isomerization of the C=C axle bond, followed by proton delivery to the quinoline nitrogen by the formation of covalent or hydrogen bonds. The axle‘s being either an imine or ketimine bond is the structural difference between the studied compounds. The −CH3 group in the latter provides steric strain, resulting in different proton transport pathways. Both compounds show long thermal stability in the switched state, which creates a tuneable action of bidirectional proton cargo transport by using different wavelengths of irradiation. Upon the addition of acid, the quinoline nitrogen is protonated; this results in E/Z configuration switching of the acylhydrazone subunits. This was proven by single‐crystal X‐ray structure analysis and NMR spectroscopy.
Wettability alteration using functionalized nanoparticles with tailored adhesion to the rock surface for condensate banking mitigation
Authors: Sayed Mohammed , Ow Hooisweng , Saini Rajesh , Wang Zixing
Published: June 2021

Accumulation of liquids near the wellbore in gas reservoirs can result in what is known as liquid banking, causing loss of gas and liquid production. One of the techniques that can be used to mitigate liquid banking is changing the rock wettability from liquid wetting to neutral wetting, allowing the gas to carry the liquid out of the pore space. Double‐functionalized wettability altering silica (SiO2) nanoparticles (NPs) were developed. The synthesized NPs were functionalized with both fluoro‐silane (F‐SiO2 NPs) and a charged functional group to enable coupling of the NPs to the substrate. Surfaces treated with F‐SiO2 NPs functionalized with coupling functional group showed superior wear and corrosion resistance in high salinity water compared to single‐functionalized F‐SiO2 NPs. By functionalizing 125 nm SiO2 NPs first with polyethylenimine (PEI‐) or N‐(2‐Aminoethyl)‐3‐aminopropyltrimethoxysilane (DAMO‐) l group followed by fluorination, a water contact angle of 120°and decane contact angle of 70° was achieved. Core flow testing performed under realistic reservoir conditions of pressure and temperature showed that F‐SiO2 NPs coated with PEI achieved a 58% improvement in gas and liquid relative permeability, indicating improvement in the surface repellency to liquids and reduction of the trapped liquid phases inside the pore space of the rocks. The developed double‐functionalized NPs achieved similar performance to the commercially used fluorinated surfactants but using less treatment volume. In addition, these double‐functionalized NPs enable one‐step treatment in the field, which results in simpler operations, shorter treatment time, and better treatment economics.
Solving tridiagonal Toeplitz systems of linear equations on GPU‐accelerated computers
Authors: Dmitruk Beata , Stpiczyński Przemysław
Published: June 2021

The aim of this article is to show that solvers for tridiagonal Toeplitz systems of linear equations can be efficiently implemented for a variety of modern GPU‐accelerated and multicore architectures using OpenACC. We consider two parallel algorithms for solving such systems with special assumptions about coefficient matrices. As the first algorithm, we propose a new, faster implementation of the divide and conquer method. The next algorithm is a new, vectorizable algorithm based on a recently introduced sequential method. We consider the use of both column‐wise and row‐wise storage formats for two‐dimensional arrays and show how to efficiently convert between these two formats using cache memory and improve the overall performance of our implementations. We also show how to tune the performance by predicting the best values of the methods' parameters. Numerical experiments performed on Intel CPUs and Nvidia GPUs show that our new implementations achieve relatively good performance and accuracy.
Imaging peculiarities of gubernaculum tracts in molars as accessional teeth on CT
Authors: Oda Masafumi , Nishida Ikuko , Habu Manabu , Takahashi Osamu , Tabe Shirou , Tsurushima Hiroki , Otani Taishi , Yoshiga Daigo , Sago Teppei , Tanaka Tatsurou , Wakasugi‐Sato Nao , Matsumoto‐Takeda Shinobu , Sasaguri Masaaki , Morimoto Yasuhiro
Published: June 2021

Objectives

The shapes of gubernaculum tracts (GTs) in molars as accessional teeth remain unidentified. To elucidate imaging peculiarities of GTs in molars with aging on multidetector‐row computed tomography (MDCT).

Material and methods

This retrospective study was conducted using CT images, including maxillary and mandibular molars, with no abnormal findings from 239 patients. Shapes of alveolar bone, GTs, and dental sacs of the maxillary and mandibular molars were analyzed multi‐sectionally. Correlations between 2‐ and 3‐dimensional imaging figures of GTs in molars and chronological age or stage of molar formation were analyzed.

Results

Some forms of GTs in maxillary and mandibular third molars were observed. In the early stage, GTs were visualized as bone defect lines on the dentition and grooves on the mesial alveolar crest continuous with the dental sac to mesial tooth bud. GTs of the third molar formed a J‐shape in maxillary teeth and Y‐shape in mandibular teeth in the middle stage, as alveolar bone around the GT developed. In the mature stage, the course of the GT changed to straight and perpendicular. Some GT forms were also identified in first and second molars. Significant correlations were found between GT alterations and chronological age or stage of molar formation. Moreover, tracts continuing from the distal side of mandibular third molars were detected.

Conclusions

This paper describes the peculiarities and process of progression for GTs in molars, and the existence of tracts continuing from the distal side of mandibular third molars, unlikely dentition with deciduous predecessors. These preliminary data should prove beneficial for studies focusing on GTs in molars.
Highly Selective Production of Ethanol Over Hierarchical Bi@Bi2MoO6 Composite via Bicarbonate‐Assisted Photocatalytic CO2 Reduction
Authors: Zhao Dawei , Xuan Yimin , Zhang Kai , Liu Xianglei
Published: June 2021

Photocatalytic CO2 reduction is a sustainable and inexpensive method to solve the energy crisis and the greenhouse effect. However, the major stumbling blocks such as poor product selectivity, low yield of the multi‐carbon products, and serious recombination of electron‐hole pairs hinder practical application of photocatalysts. Herein, a high‐performance Bi@Bi2MoO6 photocatalyst, Bi nanoparticles grown on the surface of Bi2MoO6 nanosheets with oxygen vacancies, was fabricated via a simple solvothermal approach. Benefiting from the abundant active sites and effective separation of photogenerated carriers of Bi2MoO6 nanosheets, and the localized surface plasmon resonance effect of Bi nanoparticles, the Bi@Bi2MoO6 sample exhibited great photocatalytic CO2 reduction activity. Furthermore, adding NaHCO3 into the system not only significantly increased the C2H5OH generation rate but also enhanced the product selectivity. In the photocatalytic measurement (0.17 mol L−1 CO2‐saturated NaHCO3 solution), the highest formation rates of CO, CH3OH, and C2H5OH were reached at 0.85, 0.59, and 17.93 μmol g−1 h−1 (≈92 % selectivity), respectively.
An approximate statistical analysis of wireless channel over α − μ shadowed fading channel
Authors: Upaddhyay Vipin Kumar , Soni Sanjay K. , Chauhan Puspraj Singh
Published: June 2021

In this work, we have comprehensively investigated the impact of non‐linearity (α − μ) and shadowing (inverse gamma) collectively over the wireless channel. To this effect, an approximate closed‐form probability density function (PDF) expression is derived over α − μ/inverse gamma fading channel by employing Gauss–Laguerre quadrature polynomial. The accuracy of the proposed approximate solution is validated through the Kullback–Leibler divergence test. Subsequently, the proposed solution is utilized in the development of various fundamental statistics like commutative distribution function (CDF), moment generating function (MGF) and nth moment. This contribution also includes the derivation of coding gain and diversity gain to study average symbol error probability (SEP) with MRC and EGC diversity. It is observed that diversity gain is independent of shadowing and as the channel condition improves, the coding gain decreases. Finally, the closed‐form solutions of spectral efficiency under different adaptive transmission policies are also developed specifically, optimal power and rate adaptation (OPRA) and effective capacity along with simpler low‐ and high‐power expressions. Monte‐Carlo simulations are utilized to validate the proposed analytical and numerical results.
Metonitazene in the United States—Forensic toxicology assessment of a potent new synthetic opioid using liquid chromatography mass spectrometry
Authors: Krotulski Alex J. , Papsun Donna M. , Walton Sara E. , Logan Barry K.
Published: June 2021

Metonitazene is considered a new psychoactive substance (NPS) and emerging potent synthetic opioid, causing increased public health concern beginning in 2020. Metonitazene joins a growing list of new synthetic opioids (NSOs) contributing to deaths among people who use drugs in the United States and other parts of the world. Metonitazene (a 2‐benzylbenzimidazole analogue) first appeared in mid‐2020 in the recreational drug supply and subsequently began proliferating in death investigation casework towards the end of 2020. Screening and metabolite discovery were performed by liquid chromatography quadrupole time‐of‐flight mass spectrometry. Quantitative confirmation was performed by liquid chromatography tandem quadrupole mass spectrometry. Metonitazene was confirmed in 20 authentic forensic postmortem cases with an average concentration in blood at 6.3 ± 7.5 ng/ml (median: 3.8 ng/ml, range: 0.5–33 ng/ml, n = 18) and in urine at 15 ± 13 ng/ml (median: 11 ng/ml, range: 0.6–46 ng/ml, n = 14). Metonitazene was the only opioid identified in 30% of cases but was also found in combination with fentanyl (55%) and NPS benzodiazepines, opioids, and hallucinogens (45%). Medical examiners included metonitazene as a drug responsible for the cause of death, and the manner of death was always ruled to be an accident. The metabolism of metonitazene was found to be similar to that of isotonitazene, a closely related analogue. Toxicology laboratories and death investigators should ensure that metonitazene is included in forensic testing protocols, all while remaining vigilant for subsequent NSOs to emerge.
Do functional identity and divergence promote aboveground carbon differently in tropical semi‐arid forests and savannas?
Authors: Mensah Sylvanus , van der Plas Fons , Noulèkoun Florent
Published: June 2021

Various studies have shown that plant species richness can promote ecosystem functions such as biomass storage. However, it is less well known whether this is mostly driven by the dominance of a few species and their associated traits (functional identity), or by complementarity among species that highly vary in their traits (functional diversity). The relative contribution of functional diversity and functional identity on biomass and carbon storage may in part depend on the type of functional traits that are considered, and on ecosystem type. Here, we used forest inventory data from West African semi‐arid environments, and functional traits (wood density and tree maximum height) to examine the effects of functional trait identity (FI or community weighted mean; CWM) and diversity (FD or single functional divergence; FDvar) on aboveground carbon (AGC) storage in both forests and savannas. We fitted simple linear and structural equation models to test the direct and indirect effects of functional traits on AGC, while accounting for potential effects of vegetation stand structure such as stand density and basal area. When evaluated independently, CWM of tree maximum height and FDvar of wood density correlated positively with AGC, in both forests and savannas, whereas species richness was unrelated to AGC. However, structural equation models indicated different mechanisms by which these biodiversity components drove AGC in forests and savannas. In forests, species richness had an indirect, positive effect on AGC via basal area, but also an indirect, negative effect, through a reduction in CWM of maximum height. In savannas, species richness had a direct, negative effect on AGC, while both CWM of maximum height (through an increase in basal area) and FDvar of wood density had positive effects. Our study suggests that integrative models are crucial for understanding the effects of species richness, functional trait diversity, and identity on AGC across forests. Furthermore, our study shows that relationships between biodiversity and AGC differ among ecosystem types. In both forests and savannas, FI played an important role, as AGC was maximized in communities dominated by species with a high maximum height. However, only in savannas a high FD additionally promoted AGC.
Depressed right ventricular systolic function in heart failure due to constrictive pericarditis
Authors: Raizada Veena , Sato Kimi , Alashi Alaa , Kumar Arnav , Kwon Deborah , Ramchand Jay , Dillenbeck Amy , Zumwalt Ross E. , Vangala Adarsh S. , Earley Tyler D. , Klein Allan
Published: June 2021

Aims

Heart failure in constrictive pericarditis (CP) is attributed to impaired biventricular diastolic filling. However, diseases that cause CP due to myocardial infiltration and fibrosis can also impair biventricular systolic function (sf) and contribute to heart failure. This study of patients with CP examined biventricular sf and the effect of myocardial infiltration by pericardial diseases and the resulting fibrosis on ventricular sf.

Methods and results

Histopathologic examinations of right ventricular (RV) and left ventricular (LV) myocardia and pericardia were performed on three autopsied hearts of patients with pericardial diseases. Additionally, in 40 adults with clinical heart failure and 40 healthy adults (controls), sf of both ventricles was examined by echocardiography, including strain measurements, and biventricular diastolic filling and pulmonary artery pressures were assessed by cardiac catheterization. Cardiac histopathology indicated thickening of the pericardium with fibrosis, disease infiltrating the myocardium, greater infiltration of the RV than the LV, and an association of pericardial thickness with myocardial infiltrations. Functional analysis indicated that RVsf was impaired on all echo indices, including strain measurement, but LVsf was preserved.

Conclusions

Diseases causing CP are not restricted to the pericardium but also infiltrate the biventricular myocardium and affect the thin‐walled RV more than the thick‐walled LV, resulting in depressed RVsf. The present results help explain clinical heart failure in the presence of restricted diastolic filling in CP. Depression of RVsf due to progression of fibrosis in the RV myocardium may increase the risk of delayed pericardiectomy.
Novel diagnostic and therapeutic approaches to pulmonary hypertension due to the unilateral absence of a pulmonary artery
Authors: Nagamatsu Yuki , Goda Ayumi , Ito Junnosuke , Takeuchi Kaori , Kikuchi Hanako , Kariyasu Toshiya , Machida Haruhiko , Inami Takumi , Kohno Takashi , Soejima Kyoko , Satoh Toru
Published: June 2021

We report the case of a 64‐year‐old female diagnosed with severe pulmonary hypertension due to the unilateral absence of a pulmonary artery. The four‐dimensional computed tomography scan is a useful modality for revealing detailed anatomical findings for differential diagnoses and surgical decision‐making. The patient had severe pulmonary hypertension with a mean pulmonary artery pressure (PAP) of 74 mmHg and was treated with triple upfront combination therapy, leading to significant improvement in pulmonary haemodynamics (to 27 mmHg in mean PAP) and functional capacity (WHO functional class, from III to II; 6‐min walk distance, from 211 to 276 m).
Computational Organometallic Catalysis: Where We Are, Where We Are Going
Authors: Lledós Agustí
Published: June 2021

This essay gives my personal perspective of the current stage of computational methods applied to modeling organometallic catalysis, as well as the new directions the field is taking. The first part of the essay deals with what I consider the state‐of‐the‐art to build up energy profiles, regarding both chemical and computational models. With a proper choice of the chemical model and computational methods, quantum mechanical calculations are nowadays able to provide accurate energy profiles of organometallic reactions in solution involving closed‐shell species. However, in most cases they are still used to “predict the past”, providing after‐the‐fact explanations and missing out the full potential of contemporary simulation techniques. Simulations are mature enough to be incorporated at the design stage and to guide the experimental exploration. The new directions the field is taking, incorporating automated exploration methods and combined with extensive data analysis and machine learning algorithms, approach the holy grail of catalyst discovering.
Construction of Racemic and Enantiopure Biaryl Unnatural Amino Acid Derivatives via Pd(II)‐Catalyzed Arylation of Unactivated Csp3−H Bonds
Authors: Banga Shefali , Kaur Ramandeep , Babu Srinivasarao Arulananda
Published: June 2021

We report the construction of racemic and enantiopure biaryl unnatural amino acid derivatives via the palladium‐catalyzed stereoselective sp3 C−H activation and arylation of amino acid derivatives with iodobiaryls. The synthesis of biaryl motif installed (DL‐), L‐ and D‐amino acid derivatives including norvaline, phenylalanine, leucine, norleucine and 2‐aminooctanoic acid with anti stereochemistry is reported. The synthesis of alanine derivatives with two biaryl motifs and aminoalkanoic acids with biaryl motifs is also shown. The C−H arylation of enantiopure carboxamides gave biaryl amino acid derivatives with good enantiopurity. Removal of the directing group 8‐aminoquinoline, deprotection of the phthalimide moiety, and the preparation of biaryl amino acid derivatives containing free amino‐ and carboxylate groups are also reported. The stereochemistry (anti) of representative major diastereomers was unequivocally ascertained from X‐ray structure analysis. Biaryl amino acids/peptides are important motifs in medicinal chemistry, and this work therefore represents a contribution towards enriching the library of biaryl amino acids.
Episodic master narratives through time: Exploring the temporal dynamism of 2016 election night stories
Authors: Dunlop William L. , Wilkinson Dulce E. , Harake Nicole R.
Published: June 2021

Master narratives are culturally vetted stories that guide collective action. Over an 18‐month period, we examined the dynamism inherent in master narratives of the 2016 American presidential election. In assessments separated six months apart, four independent samples of Clinton and Trump voters provided their stories of election night 2016 and rated the positivity and vividness of these experiences. Narratives were additionally quantified along both linguistic (I‐talk and We‐talk) and conceptual (redemption and contamination) dimensions. Over time: (a) election night experiences became less vivid, (b) the proportion of We‐words in election night narratives increased (suggesting greater group identification), (c) Clinton supporters’ evaluations of their election nights became marginally more positive (suggesting an increased optimism), and (d) Trump supporters’ narratives became less redemptive (suggesting a reduced enthusiasm for this historical event). These results signal the enduring and dynamic elements of the narratives central to two of America's diametrically opposed sociopolitical groups.
Magma mixing in the genesis of the Qingshanbao granitoids in the Longshoushan area: Implications for the tectonic evolution of the North Qilian orogenic belt, NW China
Authors: Liu Wen‐Heng , Spier Carlos , Niu Yu‐Ben , Liu Xiao‐Dong , Yan Jie , Wang Kai‐Xing , Pan Jia‐Yong
Published: June 2021

The geochemical differences of magmatic rocks can be influenced by melt source and magmatic processes, including partial melting, fractional crystallization and magma mixing. New whole‐rock geochemical analyses, zircon U–Pb ages and Hf‐isotope data on granitoids from the Qingshanbao complex in the Longshoushan belt highlight a significant Late Ordovician–Early Silurian magmatic episode during the collision between the Alxa and Qilian‐Qaidam blocks, in which magma mixing was a fundamental process. The Qingshanbao complex comprises K‐feldspar granite, granodiorite and diorite emplaced coevally from 442 to 433 Ma. They exhibit peraluminous to metaluminous I‐type features, are enriched in large‐ion lithophile elements (LILEs) and light rare earth elements (LREEs) and depleted in high‐field‐strength elements (HFSEs). Chondrite‐normalized REE patterns are fractionated (LaN/YbN = 10.2–34.9) with weakly negative Eu anomalies (Eu/Eu* = 0.66–0.94). The 176Lu/177Hf zircon two‐stage model ages (TDM2) and the εHf(t) on zircons extracted from the K‐feldspar granite (1613–2,316 Ma, εHf(t) = −14.4 to −3.0) and granodiorite (1640–2015 Ma, εHf(t) = −9.6 to −3.6) suggest they were formed by the mixing of melts produced by the melting of Mesoproterozoic crustal materials, most likely meta‐basic rocks from the Longshoushan Group, and to a lesser extent mantle materials. In contrast, zircons in the diorite yield TDM2 ages ranging from 964 to 1767 Ma and εHf(t) values of −5.5 to 7.1, implying melting of depleted mantle rocks with subordinate participation of lower crust materials. We suggest that the Qingshanbao complex was emplaced when the North Qilian area was in a transitional stage from a compressional to an extensional environment as early as approximately 442 Ma.
Significance of time‐dependent magnetohydrodynamic transient free convective flow in vertical annuli: An analytical approach with the finite Hankel transform
Authors: Anurag  , Maurya J. P. , Singh A. K.
Published: June 2021

An analytical study is accomplished by using the Finite Hankel Transform Technique for the variation of the temperature and the velocity profile with several nondimensional parameters. In this problem, an electrically conducting fluid has been considered in the vertical concentric annulus, with a perpendicular radial magnetic field. Furthermore, a closed and exact type of expression for the velocity and the temperature are received in the form of Bessel functions of both kinds (first and second). The impact of emerging parameters in this model, such as time, Hartmann number, Prandtl number, and the annular gap between the cylinders, is discussed through graphs, whereas the numerical values of the skin friction, mass flux, and the Nusselt number are given in the tabular form. As a consequence of this, it is detected that the velocity and temperature distributions are increasing continuously with an enhanced time scale. Eventually, it gains its steady state very quickly. Moreover, the impact of the Prandtl number and the Hartmann number leads to a decrease in the velocity profiles.
In situ and ex situ bioassays with Cantareus aspersus for environmental risk assessment of metal(loid) and PAH-contaminated soils
Authors: Louzon Maxime , Pauget Benjamin , Gimbert Frédéric , Morin-Crini Nadia , Wong Janine W. Y. , Zaldibar Beñat , Natal-da-Luz Tiago , Neuwirthova Natália , Thiemann Christina , Sarrazin Bernard , Irazola Mireia , Amiot Caroline , Rieffel Dominique , Sousa José P. , Chalot Michel , de Vaufleury Annette
Published: June 2021

Environmental risk assessment of contaminated soils requires bioindicators that allow the assessment of bioavailability and toxicity of chemicals. Although many bioassays can determine the ecotoxicity of soil samples in the laboratory, few are available and standardized for on-site application. Bioassays based on specific threshold values that assess the in situ and ex situ bioavailability and risk of metal(loid)s and polycyclic aromatic hydrocarbons (PAHs) in soils to the land snail Cantareus aspersus have never been simultaneously applied to the same soils. The aims of this study were to compare the results provided by in situ and ex situ bioassays and to determine their respective importance for environmental risk assessment. The feasibility and reproducibility of the in situ bioassay were assessed using an international ring test. This study used five plots located at a former industrial site and six laboratories participated in the ring test. The results revealed the impact of environmental parameters on the bioavailability of metal(loid)s and PAHs to snails exposed in the field to structured soils and vegetation compared to those exposed under laboratory conditions to soil collected from the same field site (excavated soils). The risk coefficients were generally higher ex situ than in situ, with some exceptions (mainly due to Cd and Mo), which might be explained by the in situ contribution of plants and humus layer as sources of exposure of snails to contaminants and by climatic parameters. The ring test showed good agreement among laboratories, which determined the same levels of risk in most of the plots. Comparison of the bioavailability to land snails and the subsequent risk estimated in situ or ex situ highlighted the complementarity between both approaches in the environmental risk assessment of contaminated soils, namely, to guide decisions on the fate and future use of the sites (e.g., excavation, embankments, and land restoration). Integr Environ Assess Manag 2022;18:539–554. © 2021 SETAC

KEY POINTS

The comparison of the bioavailability to land snails and the subsequent ecotoxicological risk of the metal(loid)s and the PAHs estimated in situ or ex situ highlighted the complementarity between the field and laboratory approaches to assess the environmental risk of contaminated soils.  The method is now submitted as an ISO standard (ISO 24032).  This ISO standard gives tools for the assessment in situ (and ex situ) of the bioavailability and environmental risk of numerous contaminants.  This original validated method should help strengthen the positioning and use of combined chemical and biological tools in environmental risk assessment of contaminated soils and sites.
Effect of sudden canal contraction on the discharge coefficient and the energy dissipation coefficient of the elliptical LOPAC gate*
Authors: Kheybar Hooman , Sajjadi Seyed Mohsen , Ahadiyan Javad
Published: June 2021

Gates are usually made with a width smaller than the width of the canal to reduce construction and operation costs. In this study, the effect of a sudden contraction of the canal cross‐section on the hydraulic performance of the elliptical LOPAC (EL) gate was investigated in vitro. To that end, 108 experiments were carried out at three different flow discharges (25, 35, and 45 L/s), four different gate widths or sudden canal contractions (b = 50, 60, 70, and 80 cm), three different submergence ratios (Yt/Yu = 0.7, 0.8, and 0.9), and three different gate‐closing angles (15, 20, and 25). For this purpose, using the discharge coefficient and energy dissipation coefficient, distinct equations were obtained to estimate the discharge of the EL gate. By presenting an empirical relation, the discharge coefficient was estimated with a maximum error of ±9%. Experimental results showed that due to the sudden canal contraction, the discharge coefficient of the gate indicates a decrease of about 14%–73%. The energy drop coefficient for the EL gate was obtained based on experimental data. The energy dissipation coefficient was calculated to be 1.3 for the velocity head at the output of the EL gate, which estimated the discharge with a maximum error of ±11%.
Assessing the Accuracy and Reproducibility of PARIETAL: A Deep Learning Brain Extraction Algorithm
Authors: Valverde Sergi , Coll Llucia , Valencia Liliana , Clèrigues Albert , Oliver Arnau , Vilanova Joan C. , Ramió‐Torrentà Lluís , Rovira Àlex , Lladó Xavier
Published: June 2021

Background

Manual brain extraction from magnetic resonance (MR) images is time‐consuming and prone to intra‐ and inter‐rater variability. Several automated approaches have been developed to alleviate these constraints, including deep learning pipelines. However, these methods tend to reduce their performance in unseen magnetic resonance imaging (MRI) scanner vendors and different imaging protocols.

Purpose

To present and evaluate for clinical use PARIETAL, a pre‐trained deep learning brain extraction method. We compare its reproducibility in a scan/rescan analysis and its robustness among scanners of different manufacturers.

Study Type

Retrospective.

Population

Twenty‐one subjects (12 women) with age range 22–48 years acquired using three different MRI scanner machines including scan/rescan in each of them.

Field Strength/Sequence

T1‐weighted images acquired in a 3‐T Siemens with magnetization prepared rapid gradient‐echo sequence and two 1.5 T scanners, Philips and GE, with spin‐echo and spoiled gradient‐recalled (SPGR) sequences, respectively.

Assessment

Analysis of the intracranial cavity volumes obtained for each subject on the three different scanners and the scan/rescan acquisitions.

Statistical Tests

Parametric permutation tests of the differences in volumes to rank and statistically evaluate the performance of PARIETAL compared to state‐of‐the‐art methods.

Results

The mean absolute intracranial volume differences obtained by PARIETAL in the scan/rescan analysis were 1.88 mL, 3.91 mL, and 4.71 mL for Siemens, GE, and Philips scanners, respectively. PARIETAL was the best‐ranked method on Siemens and GE scanners, while decreasing to Rank 2 on the Philips images. Intracranial differences for the same subject between scanners were 5.46 mL, 27.16 mL, and 30.44 mL for GE/Philips, Siemens/Philips, and Siemens/GE comparison, respectively. The permutation tests revealed that PARIETAL was always in Rank 1, obtaining the most similar volumetric results between scanners.

Data Conclusion

PARIETAL accurately segments the brain and it generalizes to images acquired at different sites without the need of training or fine‐tuning it again. PARIETAL is publicly available.

Level of Evidence

2

Technical Efficacy Stage

2
Salt tolerance at vegetative stage is partially associated with changes in grain quality and starch physicochemical properties of rice exposed to salinity stress at reproductive stage
Authors: Sangwongchai Wichian , Krusong Kuakarun , Thitisaksakul Maysaya
Published: June 2021

BACKGROUND

Rice yield and grain quality are highly sensitive to soil salinity. Distinct rice genotypes respond to salinity stress differently. To explore the variation in grain yield and grain trait adaptation to moderate, reproductive‐stage salinity stress (4 dS/m electrical conductivity), four rice cultivars differing in degrees of vegetative salt tolerance, including Pokkali (salt‐tolerant), RD15 (moderately salt‐tolerant), KDML105 (moderately salt‐susceptible) and IR29 (salt‐susceptible), were examined.

RESULTS

Grain fertility and 100‐grain weight of RD15, KDML105 and IR29, as well as grain morphology of KDML105 and IR29, were significantly disturbed. Interestingly, grain starch accumulation in RD15 and KDML105 was enhanced under stress. However, only RD15 showed changes in starch physicochemical properties, including increased granule diameter, decreased gelatinization peak temperature (Tp) and decreased retrogradation onset temperature (To). Notably, Pokkali maintained productivity, grain quality, and starch properties, while the grain quality of IR29 remained unchanged under salinity stress. Multivariate analysis displayed clear separation of productivity, grain morphology, and starch variables of RD15 in the salt‐treated group relative to the control group, suggesting that it was the cultivar most impacted by salt stress despite its moderate salt‐tolerance at vegetative stage.

CONCLUSION

Our results demonstrate specific salinity responses among the rice genotypes, and suggest discrepancies between degrees of salt tolerance at vegetative stage versus the ability to maintain both grain quality and starch properties in response to salinity stress imposed at reproductive stage. © 2021 Society of Chemical Industry.
Delay in breast cancer diagnosis and its clinical consequences during the coronavirus disease pandemic
Authors: Koca Bulent , Yildirim Murat
Published: June 2021

Objective

At the end of 1 year of the coronavirus disease (COVID‐19) pandemic, we aimed to reveal the changes in breast cancer cases in the context of cause and effect based on the data of surgically treated patients in our institution.

Patients and Methods

Patients with breast cancer were divided into two groups. Group 1 consisted of patients who were operated in the year before the COVID‐19 pandemic, and Group 2 consisted of patients who were operated within the first year of the pandemic. Tumor size, axillary lymph node positivity, distant organ metastasis status, neoadjuvant chemotherapy, and type of surgery performed were compared between the two groups.

Results

The tumor size, axillary lymph node positivity, and neoadjuvant chemotherapy were higher in Group 2 than in Group 1 (p = .005, p = .012, p = .042, respectively). In addition, the number of breast‐conserving surgery + sentinel lymph node biopsy were lower, while the number of mastectomy and modified radical mastectomy were higher in Group 2 than in Group 1 (p = .034).

Conclusion

Patients presented with larger breast tumors and increased axillary involvement during the pandemic. Moreover, distant organ metastases may increase in the future.
Dual‐Responsive Soft Actuator Based on Aligned Carbon Nanotube Composite/Graphene Bimorph for Bioinspired Applications
Authors: Li Heng , Li Run , Wang Kesheng , Hu Ying
Published: June 2021

Nanocarbon‐based polymer actuators have attracted significant attention because of their excellent actuation performance. In this study, a soft bimorph actuator composed of an anisotropic carbon nanotube (CNT)–polymer composite and reduced graphene oxide (rGO) film is fabricated by a simple blade‐coating method. Owing to the excellent electrical, optical, and thermal properties of the CNT and rGO, the actuator exhibits dual‐responsive actuation. It generates reversible bending deformation with a displacement of ≈13 mm under low electrical voltage stimulation or white light irradiation. Furthermore, because of the embedment of aligned CNTs in polymer matrix, this actuator exhibits excellent mechanical output compared with many of the reported nanocarbon‐based actuators. It can lift a 2.048 g clip to a height of ≈5 mm under low electrical voltage stimulation. Based on this soft actuator with dual response and good mechanical output, various bionic devices are designed. A bionic eagle claw that grasps a soft object under electrical stimulation and an artificial flower blooming in response to light irradiation are constructed. Moreover, a light‐driven smart curtain and a seagull robot are fabricated. These results reveal the great potential of the dual‐responsive anisotropic soft actuator in soft robots and smart devices driven by electricity and light.
Tics and TikTok: Functional Tics Spread Through Social Media
Authors: Hull Mariam , Parnes Mered
Published: June 2021

Background

Functional movement disorder is a subtype of functional neurologic symptom disorder a syndrome of involuntary physical, neurologic‐type symptoms that are incongruous with “organic” disease. Throughout history, there have been outbreaks of functional symptoms in communities; until recently, spread had been confined to groups of people who shared a physical location. However, in the era of social media, a new mode of dissemination may have arisen.

Cases

We describe six teenage girls, each with the explosive onset of tic‐like movements. Mean age of onset was 14.2 years. The presence of features incongruous with Tourette syndrome on history and examination prompted the diagnosis of functional tics. All patients reported exposure to a specific social media personality before symptom onset.

Conclusions

Our series suggests that social media may contribute to the spread of functional neurologic symptom disorder, in a way previously requiring physical proximity.