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This study investigates the levels of social language and vocabulary characteristics of three‐ to six‐year‐old children with autism in Vietnam. The research is based on analysis of the developmental assessment reports of 151 children with autism, and 42 parents' reports on their children's vocabulary (recorded using the Child Word Inventory form). The findings show that about 85% of participants have a language level that is below average. The rate of accumulation of words and social language by children with autism is slower than that of typically developing children of the same age. It is also found that the participants' number of production words is 2.4 times greater than their number of reception words. Nonetheless, their receptive words have little correlation with their overall development and social language development. This implies that parents and teachers of children with autism should make a point of assisting them in enlarging and comprehending their vocabulary, to enable them to use their language (words) for effective communication. [ABSTRACT FROM AUTHOR]

In recent years, empirical Bayesian (EB) inference has become an attractive approach for estimation in parametric models arising in a variety of real‐life problems, especially in complex and high‐dimensional scientific applications. However, compared to the relative abundance of available general methods for computing point estimators in the EB framework, the construction of confidence sets and hypothesis tests with good theoretical properties remains difficult and problem specific. Motivated by the Universal Inference framework, we propose a general and universal method, based on holdout likelihood ratios, and utilizing the hierarchical structure of the specified Bayesian model for constructing confidence sets and hypothesis tests that are finite sample valid. We illustrate our method through a range of numerical studies and real data applications, which demonstrate that the approach is able to generate useful and meaningful inferential statements in the relevant contexts. [ABSTRACT FROM AUTHOR]

Summary: This article introduces a special issue of the Australian and New Zealand Journal of Statistics, dedicated as a Festschrift for Geoff McLachlan on the occasion of his 75th birthday. [ABSTRACT FROM AUTHOR]

Summary: The expectation–maximisation (EM) algorithm framework is an important tool for statistical computation. Due to the changing nature of data, online and mini‐batch variants of EM and EM‐like algorithms have become increasingly popular. The consistency of the estimator sequences that are produced by these EM variants often rely on an assumption regarding the continuous differentiability of a parameter update function. In many cases, the parameter update function is not in closed form and may only be defined implicitly, which makes the verification of the continuous differentiability property difficult. We demonstrate how a global implicit function theorem can be used to verify such properties in the cases of finite mixtures of distributions in the exponential family, and more generally, when the component‐specific distributions admit data augmentation schemes, within the exponential family. We then illustrate the use of such a theorem in the cases of mixtures of beta distributions, gamma distributions, fully visible Boltzmann machines and Student distributions. Via numerical simulations, we provide empirical evidence towards the consistency of the online EM algorithm parameter estimates in such cases. [ABSTRACT FROM AUTHOR]

Perfluorinated‐sulfonic‐acid‐based ionomers (PFSAs) are still the material of choice for electrochemical energy devices such as proton‐exchange membrane fuel cells or water electrolyzers. However, PFSAs show significant drawbacks ranging from a restricted temperature window of operation due to the insufficient thermomechanical stability, high cost, and questionable environmental properties. Recently, novel hydrocarbon‐based ionomers have been introduced, which not only have the potential to overcome these limitations, but also for the first time show promising performance, approaching that of PFSA‐based fuel cells and electrolyzers. This article summarizes the recent developments in this emerging field with a particular focus on the engineering of membrane‐electrode assemblies with hydrocarbon‐based polymer electrolytes. In the final part, the necessary key innovations are discussed, which are required for hydrocarbon ionomers to replace PFSAs in fuel cells and electrolyzers in the future. [ABSTRACT FROM AUTHOR]

Topotactic transitions, that is, reversible crystal structure changes due to controllable stoichiometry of material, offer substantial potential to control a wide variety of functionality in transition metal oxides, especially in systems with high ionic mobility and correlated electrons. Here the authors report on topotactic electrochromism with prominent coloration efficiency in SrCo0.66Fe0.34O3−δ associated with changes of electrical conductivity and electronic structure of the material. Changes in electron correlation lead to significant coloration and light absorption, which provides a general approach for utilizing topotactic transitions in electrochromic applications. [ABSTRACT FROM AUTHOR]

A broadly applicable methodology for the regio‐ and enantioselective construction of branched allylic carbon‐heteroatom bonds from racemic, secondary allylic trichloroacetimidates has been developed. The branched allylic substrates undergo dynamic kinetic asymmetric substitution reactions with a number of unactivated anilines and carboxylic acids as well as unactivated aromatic thiols in the presence of a chiral bicyclo[3.3.0]octadiene‐ligated iridium catalyst. The allylic C−O, C−N, and C−S bond containing products are obtained in synthetically useful yield and selectivity. Mechanistic studies suggest that the iridium‐catalyzed enantioselective substitution reactions of heteroatom nucleophiles with allylic trichloroacetimidate substrates through an outer‐sphere nucleophilic addition mechanism. In addition, the chiral diene‐ligated iridium catalyst is effective at promoting asymmetric aminations of acyclic secondary anilines. Importantly, this catalytic iridium methodology enables the use of alkyl substituted allylic electrophiles. [ABSTRACT FROM AUTHOR]

Phenanthroline, a rigid and planar compound with two fused pyridine rings, has been used as a powerful ligand for metals and a binding agent for DNA/RNA. We discovered that phenanthroline could be used as a nucleophilic catalyst to efficiently access high yielding and diastereoselective α‐1,2‐cis glycosides through the coupling of hydroxyl acceptors with α‐glycosyl bromide donors. We have conducted an extensive investigation into the reaction mechanism, wherein the two glycosyl phenanthrolinium ion intermediates, a 4C1 chair‐liked β‐conformer and a B2,5 boat‐like α‐conformer, have been detected in a ratio of 2:1 (β:α) using variable temperature NMR experiments. Furthermore, NMR studies illustrate that a hydrogen bonding is formed between the second nitrogen atom of phenanthroline and the C1‐anomeric hydrogen of sugar moiety to stabilize the phenanthrolinium ion intermediates. To obtain high α‐1,2‐cis stereoselectivity, a Curtin‐Hammett scenario was proposed wherein interconversion of the 4C1 chair‐like β‐conformer and B2,5 boat‐like α‐conformer is more rapid than nucleophilic addition. Hydroxyl attack takes place from the α‐face of the more reactive 4C1 β‐phenanthrolinium intermediate to give an α‐anomeric product. The utility of the phenanthroline catalysis is expanded to sterically hindered hydroxyl nucleophiles and chemoselective coupling of an alkyl hydroxyl group in the presence of a free C1‐hemiacetal. In addition, the phenanthroline‐based catalyst has a pronounced effect on site‐selective couplings of triol motifs and orthogonally activates the anomeric bromide leaving group over the anomeric fluoride and sulfide counterparts. [ABSTRACT FROM AUTHOR]

Fluid pressurization of critically stressed sheared zones can trigger slip mechanisms at work in many geological processes. Using discrete element modeling, we simulate pore‐pressure‐step creep test experiments on a sheared granular layer under a sub‐critical stress state to investigate the micromechanical processes at stake during fluid induced reactivation. The global response is consistent with available experiments. The progressive increase of pore pressure promotes slow steady creep at sub‐critical stress states, and fast accelerated dynamic slip once the critical strength is overcome. Our multi‐scale analyses show that these two emergent behaviors correlate to characteristic deformation modes: diffuse deformation during creep, and highly localized deformation during rupture. Creep corresponds to bulk deformation while rupture results from grain rotations initiating from overpressure induced unlocking of contacts located within the shear band which, consequently, acts as a roller bearing for the surrounding bulk. Plain Language Summary: Fluids can be at the origin of catastrophic disasters, e.g., earthquakes related to deep subsurface fluid injections or lanslides triggered by short‐term changes of hydrological conditions. It is now well assumed that these phenomena originate from mechanisms taking place in critically stressed shear zones found along tectonic faults, rock mass fractures or localized deformation bands. The increase of pore pressure promotes slip along these shear zones as confirmed by numerous experimental and numerical studies. In this work, we present computer simulations that reproduce the progressive reactivation of a granular shear zone as a result of fluid pressurization. Our simulations provide grain‐scale information that improves understanding of fluid induced slip behaviors and illuminate micromechanical details of phenomenological, macroscale observations. Key Points: Fluid induced reactivation can be either stable or unstable depending on the deformation modeSlow steady creep is accommodated through distributed bulk deformation at sub‐critical stress statesAccelerated dynamic slip results from intense grain rearrangements localized within the shear band [ABSTRACT FROM AUTHOR]

L7652 --> 947.32 --> Background: Endothelial cells help maintain vascular homeostasis mainly by balancing interplay between vasorelaxation and vasoconstriction via regulating availability of Nitric Oxide (NO). Endothelial nitric oxide synthase (eNOS) is one of three NOS isoforms that catalyses the synthesis of NO to regulate endothelial function. To date, however, eNOS's role in endothelial cell proliferation, remains unclear. Methods and Results: To gain a better understanding about eNOS and cell proliferation, we genetically inhibited eNOS viasilencing by transfecting cultured human umbilical vein endothelial cells with sieNOS or scrambled control. Successful eNOS silencing was confirmed at transcript and protein levels, and then endothelial cell proliferation was evaluated. Surprisingly, loss of eNOS significantly induced endothelial cell proliferation, concomitant with significant downregulation of both cell cycle inhibitor p21 and cell proliferation antigen Ki‐67. To confirm the specificity of eNOS silencer, we used another sieNOS molecule, which also showed the similar results as endothelial proliferation was significantly induced in eNOS‐silenced endothelial cells. Later, to demonstrate that the induced endothelial cell proliferation is due to eNOS inhibition, we pharmacologically inhibited eNOS by treating endothelial cells with L‐NAME. Contrastingly, L‐NAME‐treatment significantly inhibited endothelial cell proliferation in a dose‐dependent manner. Conclusion: Our findings, for the first time, indicate that eNOS regulate endothelial function by directly controlling endothelial cell proliferation. Observed inhibition of endothelial cell proliferation by L‐NAME, may be due to its non‐specific effects. The findings also indicate that eNOS and L‐NAME might employ different pathways regulating endothelial cell proliferation warranting further investigation. [ABSTRACT FROM AUTHOR]

Although there are many methods for the asymmetric synthesis of monosubstituted allylic fluorides, construction of enantioenriched 1,2‐disubstituted allylic fluorides has not been reported. To address this gap, we report an enantioselective synthesis of 1,2‐disubstituted allylic fluorides using chiral diene‐ligated rhodium catalyst, Et3N ⋅ 3HF as a source of fluoride, and Morita Baylis Hillman (MBH) trichloroacetimidates. Kinetic studies show that one enantiomer of racemic MBH substrate reacts faster than the other. Computational studies reveal that both syn and anti π‐allyl complexes are formed upon ionization of allylic substrate, and the syn complexes are slightly energetically favorable. This is in contrast to our previous observation for formation of monosubstituted π‐allyl intermediates, in which the syn π‐allyl conformation is strongly preferred. In addition, the presence of an electron‐withdrawing group at C2 position of racemic MBH substrate renders 1,2‐disubstituted π‐allyl intermediate formation endergonic and reversible. To compare, formation of monosubstituted π‐allyl intermediates was exergonic and irreversible. DFT calculations and kinetic studies support a dynamic kinetic asymmetric transformation process wherein the rate of isomerization of the 1,2‐disubstituted π‐allylrhodium complexes is faster than that of fluoride addition onto the more reactive intermediate. The 1,2‐disubstituted allylic fluorides were obtained in good yields, enantioselectivity, and branched selectivity. [ABSTRACT FROM AUTHOR]

Although there are many methods for the asymmetric synthesis of monosubstituted allylic fluorides, construction of enantioenriched 1,2‐disubstituted allylic fluorides has not been reported. To address this gap, we report an enantioselective synthesis of 1,2‐disubstituted allylic fluorides using chiral diene‐ligated rhodium catalyst, Et3N ⋅ 3HF as a source of fluoride, and Morita Baylis Hillman (MBH) trichloroacetimidates. Kinetic studies show that one enantiomer of racemic MBH substrate reacts faster than the other. Computational studies reveal that both syn and anti π‐allyl complexes are formed upon ionization of allylic substrate, and the syn complexes are slightly energetically favorable. This is in contrast to our previous observation for formation of monosubstituted π‐allyl intermediates, in which the syn π‐allyl conformation is strongly preferred. In addition, the presence of an electron‐withdrawing group at C2 position of racemic MBH substrate renders 1,2‐disubstituted π‐allyl intermediate formation endergonic and reversible. To compare, formation of monosubstituted π‐allyl intermediates was exergonic and irreversible. DFT calculations and kinetic studies support a dynamic kinetic asymmetric transformation process wherein the rate of isomerization of the 1,2‐disubstituted π‐allylrhodium complexes is faster than that of fluoride addition onto the more reactive intermediate. The 1,2‐disubstituted allylic fluorides were obtained in good yields, enantioselectivity, and branched selectivity. [ABSTRACT FROM AUTHOR]

Heparan sulfate (HS) contains variably repeating disaccharide units organized into high‐ and low‐sulfated domains. This rich structural diversity enables HS to interact with many proteins and regulate key signaling pathways. Efforts to understand structure‐function relationships and harness the therapeutic potential of HS are hindered by the inability to synthesize an extensive library of well‐defined HS structures. We herein report a rational and expedient approach to access a library of 27 oligosaccharides from natural aminoglycosides as HS mimetics in 7–12 steps. This strategy significantly reduces the number of steps as compared to the traditional synthesis of HS oligosaccharides from monosaccharide building blocks. Combined with computational insight, we identify a new class of four trisaccharide compounds derived from the aminoglycoside tobramycin that mimic natural HS and have a strong binding to heparanase but a low affinity for off‐target platelet factor‐4 protein. [ABSTRACT FROM AUTHOR]

Heparan sulfate (HS) contains variably repeating disaccharide units organized into high‐ and low‐sulfated domains. This rich structural diversity enables HS to interact with many proteins and regulate key signaling pathways. Efforts to understand structure‐function relationships and harness the therapeutic potential of HS are hindered by the inability to synthesize an extensive library of well‐defined HS structures. We herein report a rational and expedient approach to access a library of 27 oligosaccharides from natural aminoglycosides as HS mimetics in 7–12 steps. This strategy significantly reduces the number of steps as compared to the traditional synthesis of HS oligosaccharides from monosaccharide building blocks. Combined with computational insight, we identify a new class of four trisaccharide compounds derived from the aminoglycoside tobramycin that mimic natural HS and have a strong binding to heparanase but a low affinity for off‐target platelet factor‐4 protein. [ABSTRACT FROM AUTHOR]

Quinoline derivatives are important moieties in bioactive molecules and advanced materials. However, an efficient strategy to synthesize quinoline derivatives remains challenging. Herein, we describe an efficient and practical method for the synthesis of quinolines by Cu‐catalyzed cyclization of 2‐amino benzyl alcohol with ketones (or secondary alcohols) via an acceptorless dehydrogenation pathway. Interestingly, a range of highly functionalized quinolines is prepared in good yields using low catalyst loading under relatively mild conditions. Furthermore, density functional theory (DFT) calculations are carried out to investigate mechanistic insights for the acceptorless dehydrogenation pathway. [ABSTRACT FROM AUTHOR]

We examined the role of right‐wing authoritarianism (RWA), social dominance orientation (SDO), psychological entitlement, and narcissistic entitlement in the prediction of White men's negative attitudes and behaviors toward lesbian women and gay men. The present study (a) simultaneously examines four predictors (i.e., psychological and narcissistic entitlement, RWA, and SDO) of attitudes toward lesbian women and gay men (ATLG) and rejecting behaviors, (b) examines psychological and narcissistic entitlement as distinct predictors of ATLG and rejecting behaviors, and (c) tests the potential mediating role of ATLG. A path model was tested using the survey data from 153 White, heterosexual, male college students. Findings indicate that only RWA and narcissistic entitlement were significant predictors of ATLG, which is a strong predictor of rejecting behaviors. Furthermore, ATLG mediates the relationship between RWA and rejecting behaviors (d =.35). In other words, higher RWA is associated with higher ATLG, which is associated with more self‐reported rejecting behaviors. Narcissistic entitlement also influences rejecting behaviors through ATLG and both psychological and narcissistic entitlement were found to directly predict gay and lesbian rejecting behaviors. [ABSTRACT FROM AUTHOR]