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Ultra‐long room temperature phosphorescence (ULRTP) materials show valuable applications in encryption, biological imaging, and many other fields. Amazingly, the concomitant impurities from raw materials that are normally ignored contribute dramatically to the ULRTP. In this study, CzPMB [9‐(4‐bromo‐3‐methylphenyl)‐9H‐carbazole] with phosphorescent quantum efficiency of 64% is prepared from commercial carbazole, but the phosphorescent efficiency is drastically reduced to < 2% once trace impurity (5‐(4‐bromo‐3‐methylphenyl)‐5H‐benzo[b]carbazole) is separated. HPLC studies demonstrated the separated impurity is a byproduct derived from trace benzocarbazole in commercial carbazole. Subsequently, the ULRTP for the CzPMB synthesized from lab‐made carbazole is totally unobserved, strongly confirming the dramatic impact of impurity. A defect trapping mechanism in multicomponent system rather than heavy atom effect is proposed for highly efficient ULRTP after carefully analyzing the crystal packings and molecular energy levels. Inspired by this discovery, a series of effective ULRTP bi‐component systems with the highest phosphorescence efficiency of 64.1% are reproduced by directed host‐guest doping. This strategy paves a viable path for the design of organic materials with highly efficient ULRTP. [ABSTRACT FROM AUTHOR]

Circular polarized luminescence (CPL)‐active materials attract great attentions owing to their widely applications in 3D optical displays and encrypted transmission. Inspired by the strategies adopted in perovskite based CPL materials, herein, CPL‐active hybrids (D)‐ and (L)‐(tert‐butyl prolinate)MnCl3 were successfully prepared by assembling chiral D/L tert‐butyl prolinate with manganese (II) chloride. Single crystal structures show the as‐formed hybrids possess one‐dimensional (1D) structure containing linear chains of face‐sharing MnCl6 octahedral surrounded by prolinate cations. The 1D Mn(II) hybrids display strong red emission peaked at 646 nm with PLQY of 67.1 % and 57.2 % for d‐type and l‐type, respectively, representing the highest PLQY for 1D MnII hybrids. Interestingly, the 1D Mn(II) hybrids exhibit prominent circular dichroism (CD) signals and remarkable CPL activity with the dissymmetry factor g of 6.1*10−3 and −6.3*10−3 from 550 to 800 nm for (D)‐ and (L)‐(tert‐butyl prolinate)MnCl3, respectively, owing to the existence of chiral cations. It is worthy noted the obtained g represents the highest value for non‐lead organic–inorganic hybrids. [ABSTRACT FROM AUTHOR]

Vocalizations are often elaborate, rhythmically structured behaviors. Vocal motor patterns require close coordination of neural circuits governing the muscles of the larynx, jaw, and respiratory system. In the elaborate vocalization of Alston's singing mouse (Scotinomys teguina) each note of its rapid, frequency‐modulated trill is accompanied by equally rapid modulation of breath and gape. To elucidate the neural circuitry underlying this behavior, we introduced the polysynaptic retrograde neuronal tracer pseudorabies virus (PRV) into the cricothyroid and digastricus muscles, which control frequency modulation and jaw opening, respectively. Each virus singly labels ipsilateral motoneurons (nucleus ambiguus for cricothyroid, and motor trigeminal nucleus for digastricus). We find that the two isogenic viruses heavily and bilaterally colabel neurons in the gigantocellular reticular formation, a putative central pattern generator. The viruses also show strong colabeling in compartments of the midbrain including the ventrolateral periaqueductal gray and the parabrachial nucleus, two structures strongly implicated in vocalizations. In the forebrain, regions important to social cognition and energy balance both exhibit extensive colabeling. This includes the paraventricular and arcuate nuclei of the hypothalamus, the lateral hypothalamus, preoptic area, extended amygdala, central amygdala, and the bed nucleus of the stria terminalis. Finally, we find doubly labeled neurons in M1 motor cortex previously described as laryngeal, as well as in the prelimbic cortex, which indicate these cortical regions play a role in vocal production. The progress of both viruses is broadly consistent with vertebrate‐general patterns of vocal circuitry, as well as with circuit models derived from primate literature. [ABSTRACT FROM AUTHOR]

Chiral materials with circularly polarized luminescence (CPL) are currently attracting great attention for their wide applications in bioresponsive imaging, 3D displays, and storage of information. Herein, CPL‐active enantiomorphic hybrids (R)‐ and (S)‐C6H15Cl2NO⋅SbCl5 are obtained by self‐assembling chiral R/S‐(3‐chloro‐2‐hydroxypropyl)trimethylammonium chloride with antimony(III) chloride, giving a 0D structure with SbCl5 pyramids isolated by (3‐chloro‐2‐hydroxypropyl)trimethylammonium chloride cations. The formed enantiomers exhibit brilliant orange emission peaked at 604 nm with photoluminescence quantum yield as high as 71.2%, originating from the self‐trapped exciton emission demonstrated by photophysical characterization. Due to the existence of chiral organic cations, the enantiomers exhibit strong chiral‐optical properties with mirror‐image circular dichroism signals in ground state and obvious CPL activity with the dissymmetry factor glum of 2.5 × 10−4 and −1.6 × 10−4 for R‐type and S‐type, respectively. It should be mentioned that these are the first reported 0D hybrids with CPL‐activity. This work paves an avenue for developing eco‐friendly CPL materials with highly ‐efficient luminescence. [ABSTRACT FROM AUTHOR]

Mandibular deviation affects the biomechanical environment of the temporomandibular joint (TMJ) and causes thinning of cartilage on the deviated side. We aimed to evaluate, using a rat model, the effect of mandibular functional deviation on the TMJ in relation to the functional roles of integrin β family members. The effects of experimental functional deviation on the TMJ of 6‐week‐old Sprague–Dawley female rats, randomly assigned to control (n = 42) and experimental groups (n = 42), were evaluated at 3 days and 1, 2, 4, and 8 weeks by histological staining, immunofluorescence, real‐time quantitative polymerase chain reaction, and micro‐computed tomography. The results showed that the experimental functional shift changed the shape of condyles, thinned the cartilage, and increased the proportion of the hypertrophic layer on the deviated sides of condyles. In addition, the extracellular matrix of the condyle cartilage exhibited degradation at 1 week and subchondral trabecular bone was lost at 4 and 8 weeks. Osteoarthritis (OA)‐like changes occurred in the left and right condyles of rats in the experimental group and were aggravated over time. Integrin β family expression, especially integrin β2, was altered from week 1, possibly related to the OA‐like changes. These data may provide insight into the onset of TMJ OA. [ABSTRACT FROM AUTHOR]

Because of their roles in courtship and intrasexual competition, sexual displays are often sexually dimorphic, but we know little about the mechanisms that produce such dimorphism. Among mammals, one example is the vocalization of Alston's singing mouse (Scotinomys teguina), which consists of a series of rapidly repeated, frequency‐modulated notes. The rate and duration of songs is sexually dimorphic and androgen responsive. To understand the neuronal mechanisms underlying this sexual dimorphism, we map the sites of androgen sensitivity throughout the brain, focusing analysis along a pathway that spans from limbic structures to vocal motor regions. We find widespread expression of AR immunoreactivity (AR‐ir) throughout limbic structures important for social behavior and vocalization, including the lateral septum, extended amygdala, preoptic area and hypothalamus. We also find extensive AR staining along previously documented vocal motor pathways, including the periaqueductal gray, parabrachial nucleus, and nucleus ambiguus, the last of which innervates intrinsic laryngeal muscles. Lastly, AR‐ir is also evident in sensory areas such as the medial geniculate, inferior, and superior colliculi. A quantitative analysis revealed that males exhibited more AR‐ir than females, a pattern that was most pronounced in the hypothalamus. Despite the elaboration of vocalization in singing mice, comparison with prior literature suggests that the broad pattern of AR‐ir may be conserved across a wide range of rodents. Together these data identify brain nuclei well positioned to shape the sexually dimorphic vocalization of S. teguina and suggest that such androgen modulation of vocalization is evolutionary conserved among rodents. [ABSTRACT FROM AUTHOR]

Activation of the sympatho‐β‐adrenergic receptors (β‐ARs) system is a hallmark of heart failure, leading to fibrosis and arrhythmias. Connexin 43 (Cx43) is the most abundant gap junctional protein in the myocardium. Current knowledge is limited regarding Cx43 remodelling in diverse cell types in the diseased myocardium and the underlying mechanism. We studied cell type‐dependent changes in Cx43 remodelling due to β‐AR overactivation and molecular mechanisms involved. Mouse models of isoproterenol stimulation or transgenic cardiomyocyte overexpression of β2‐AR were used, which exhibited cardiac fibrosis and up‐regulated total Cx43 abundance. In both models, whereas Cx43 expression in cardiomyocytes was reduced and more laterally distributed, fibroblasts exhibited elevated Cx43 expression and enhanced gap junction communication. Mechanistically, activation of β2‐AR in fibroblasts in vitro elevated Cx43 expression, which was abolished by the β2‐antagonist ICI‐118551 or protein kinase A inhibitor H‐89, but simulated by the adenylyl cyclase activator forskolin. Our in vitro and in vivo data showed that β‐AR activation‐induced production of IL‐18 sequentially stimulated Cx43 expression in fibroblasts in a paracrine fashion. In summary, our findings demonstrate a pivotal role of β‐AR in mediating distinct and cell type‐dependent changes in the expression and distribution of Cx43, leading to pathological gap junction remodelling in the myocardium. [ABSTRACT FROM AUTHOR]

Chronic islet inflammation is associated with development of type 2 diabetes mellitus (T2DM). Intermediate-conductance calcium-activated K+ (KCa3.1) channel plays an important role in inflammatory diseases. However, the role and regulation of KCa3.1 in pancreatic β cells in progression of T2DM remain unclarified. In the present study, we evaluated the effect of the specific KCa3.1 channel blocker 1-[(2-chlorophenyl)diphenylmethyl]-1H-pyrazole (TRAM-34) on diabetic phenotype in the db/db model. In diabetic mice, blockade of KCa3.1 significantly improved glucose tolerance, enhanced secretion of postprandial insulin level, and reduced loss of β-cell mass through attenuating the expression and secretion of inflammatory mediators. Furthermore, in cultured pancreatic β cells, exposure to high levels of glucose or palmitic acid significantly increased expression and current density of the KCa3.1 channel as well as secretion of proinflammatory chemokines, and the effects were similarly reversed by preincubation with TRAM-34 or a NF-κB inhibitor pyrrolidinedithiocarbamate. Additionally, expression of KCa3.1 in pancreas islet cells was up-regulated by activation of NF-κB with IL-1β stimulation. In summary, up-regulated KCa3.1 due to activation of NF-κB pathway leads to pancreatic inflammation via expression and secretion of chemokines and cytokines by pancreatic β cells, thereby facilitating progression of T2DM. [ABSTRACT FROM AUTHOR]

Experiments suggest that on Pt(110) the Tafel reaction is the rate determining step in hydrogen evolution. We investigate the kinetics of this step on the unreconstructed surface by a combination of density functional theory and grand‐canonical Monte Carlo simulations. We identify two favorable reaction paths: The recombination of a hydrogen atom adsorbed on a bridge site with one adsorbed on top, and an exchange mechanism involving two hydrogen atoms adsorbed on top and one adsorbed on a bridge site. The latter results in a transfer coefficient of two in agreement with experiment, and seems to be the dominant step. [ABSTRACT FROM AUTHOR]

Summary: Under the assumption that all eigenvalues of the preconditioned Schur complement are real, we present an analytical proof for obtaining the optimal convergence factor of the real accelerated parameterized inexact Uzawa (APIU) method when P=A. It is proved that the optimal convergence factor is the same as that of the generalized successive overrelaxation method, which was published at the same time, and that it can be attained only at the unique optimum point of parameters, regardless of whether m>n or m=n. In addition, we generalize the APIU method and analyze the relationship between the APIU method and 10 additional Uzawa‐like methods. [ABSTRACT FROM AUTHOR]

Abstract: Wie in vielen Zweigen der Wissenschaft, um nicht von der Kultur im Allgemeinen zu reden, so gibt es auch in der Elektrochemie eine Reihe von wiederkehrenden Themen: Forschungsgebiete, die eine Zeit lang populär sind, dann verblassen, wenn ihre Möglichkeiten erschöpft scheinen, um Jahrzehnte später wieder aktuell zu werden, wenn Fortschritte in experimentellen oder theoretischen Techniken neue Forschungsmöglichkeiten eröffnen. Ein gutes Beispiel sind Brennstoffzellen, die fünf solcher Zyklen durchlaufen haben; aber hier soll ein allgemeineres Konzept der Kinetik diskutiert werden, nämlich der präexponentielle Faktor einer Geschwindigkeitskonstanten, der bisher zwei solcher Zyklen durchlaufen hat. Der erste Zyklus umfasst etwa die Zeitspanne 1950 bis 1980, als die Methoden der elektrochemischen Kinetik entwickelt wurden und die Interpretationen auf der Theorie des Übergangszustands basierten. Der zweite wurde durch die Wiederentdeckung der Kramers‐Theorie für Reaktionen in kondensierten Phasen ausgelöst. Dieser Kurzaufsatz soll zeigen, dass es Zeit für einen dritten Zyklus ist, der auf neuen Ergebnissen in der Elektrokatalyse beruht. [ABSTRACT FROM AUTHOR]

Abstract: Like many branches of science, not to mention culture in general, electrochemistry has a number of recurring topics: Areas of research that are popular for a certain time, then fade away as their possibilities seem to have been exhausted, only to return decades later as progress in experimental or theoretical techniques offer new possibilities for their investigation. A prime example are fuel cells, which have undergone five such cycles, but here we discuss a general concept of kinetics—the pre‐exponential factor of a rate constant—which has undergone two such cycles. The first cycle was in the 1950–1980s, when the methods of electrochemical kinetics were developed, and the interpretation was based on transition‐state theory. The second was triggered by the re‐discovery of Kramers theory for reactions in condensed phases. This Minireview will show that the time has come for a third cycle based on recent progress in electrocatalysis. [ABSTRACT FROM AUTHOR]

Abstract: Aim: This study was designed to investigate and assess fetal liver injury in a rat model of acute pancreatitis in pregnancy (APIP) as well as its possible mechanisms and potential therapeutic targets. Methods: The APIP model was induced by sodium taurocholate in Sprague–Dawley rats during the third trimester. ISO‐1, a macrophage migration inhibitory factor (MIF) antagonist, was given before the induction of APIP. In addition, sham‐operated rats at later gestation were set as controls. Histological changes in the fetal liver and maternal pancreas were assessed. Amylase and lipase activity as well as the levels of tumor necrosis factor (TNF)‐α and interleukin (IL)‐1β were examined. The expression of MIF in fetal liver was determined by immunochemistry and the expression of NF‐κB, IκBα, high mobility group box‐1 protein (HMGB1), TNF‐α, and IL‐1β in fetal liver was determined by Western blot analysis. Ultrastructures of hepatic cells in fetal rats were observed under transmission electron microscopy. Results: ISO‐1 ameliorated the following: (i) pathological injuries in maternal pancreas and fetal liver; (ii) levels of TNF‐α and IL‐1β in maternal serum; and (iii) levels of MIF, myeloperoxidase, NF‐κB, HMGB1, TNF‐α, and IL‐1β in fetal liver. Conclusion: Pathological damage and an inflammatory response in fetal liver were induced by APIP, and MIF inhibition ameliorated fetal liver injury by inhibiting the inflammatory cascade. [ABSTRACT FROM AUTHOR]

In order to develop a new mortar admixture and effectively apply black liquor, effect of grafted sulfonated black liquor on wet-ready mortar property was investigated. The results showed that when the molar ratio of sodium sulfite/formaldehyde/acetone was 0.5:2:1, the polycondensation reaction time was 2.5 h at 95°C, the sulfonation degree of the product was 2.93 mmol·g−1 and the average molecular weight ( Mw) was 13,200. When the dosage of modified product was 1.5 wt% in the mortar, the consistency loss of the mortar was 33.7% after 4h, the water retention was 90.1%, the setting time was 16.2h, and the bond strength of hardened mortar was 0.41MPa at 14d and 0.69MPa at 28d (the initial consistency was 90mm ± 5mm). This study has certain reference value for the development of wet-ready mortar admixture, also has great significance in the environmental protection and application of renewable resource. © 2016 American Institute of Chemical Engineers Environ Prog, 35: 1395-1399, 2016 [ABSTRACT FROM AUTHOR]

Organoruthenium-supported polyoxometalates [(RuC6H6)XW9O34]7- (XWRu; X=As, P)were selected as samples to study their catalytic activities towards the solvent-free oxidation of n-hexadecane. First of all, the XWRu were deposited on 3-aminopropyltriethoxysilanemodified SBA-15 to prepare solid catalysts, which were characterized using powder X-ray diffraction, nitrogen adsorption measurements, Fourier transform infrared reflectance spectroscopy and X-ray photoelectron spectroscopy. Subsequently, their catalytic performances and stabilities were assessed through the oxidation of n-hexadecane using air as the oxygen source without any additives and solvents, and the influences of the loading amount, catalyst amount, reaction time and reaction temperature on the catalytic activities were investigated. The results indicated the influence of the central heteroatoms X of XWRu on the catalytic activities. [ABSTRACT FROM AUTHOR]

KRAS mutations have been established as a major predictive biomarker for resistance to the treatment of metastatic colorectal cancer (mCRC) with anti-epidermal growth factor receptor monoclonal antibodies (anti-EGFR MoAbs). However, many patients with KRAS wild-type tumors still do not respond to the treatment. We conducted a systematic review with meta-analysis to assess whether BRAF mutations, PIK3CA mutations and PTEN loss can predict the outcomes of patients with KRAS wild-type mCRC treated with anti-EGFR MoAbs. Studies that explored the association of one or more of the three biomarkers with progression-free survival (PFS), overall survival (OS) and/or objective response rate (ORR) were identified through August 2012. Summary hazard ratios (HRs) and rate differences (RDs) and corresponding 95% confidence intervals (CIs) were calculated by using the random-effects model. BRAF mutations, PIK3CA exon 20 mutations and PTEN loss were all associated with shorter PFS (HR = 2.59, 95% CI 1.67-4.03; HR = 2.52, 95% CI 1.33-4.78 and HR = 1.75, 95% CI 1.19-2.56, respectively), shorter OS (HR = 2.74, 95% CI 1.79-4.19; HR = 3.29, 95% CI 1.60-6.75 and HR = 1.85, 95% CI 1.30-2.64, respectively) and lower ORR (RD = −36%, 95% CI −44 to −28%; RD = −38%, 95% CI −51 to −24% and RD = −41%, 95% CI −68 to −14%, respectively). PIK3CA exon 9 mutations were associated with none of the outcomes. Studies with relevant data consistently demonstrated a stronger predictive power of combined multiple biomarkers as compared to one alteration alone. These results suggest that BRAF mutations, PIK3CA exon 20 mutations and PTEN loss are predictive of better outcomes in KRAS wild-type mCRC treated with anti-EGFR MoAbs. However, the quality of included studies varied, and some of the meta-analyses were limited by significant between-study heterogeneity. In the future, well-designed large randomized controlled trials conducted in KRAS wild-type mCRC patients with subgroup analysis according to BRAF, PIK3CA exon 20 and PTEN status are essential to fully assess the clinical relevance of these biomarkers. [ABSTRACT FROM AUTHOR]

Background: The authors conducted a systematic review and meta-analysis to examine whether patients who had metastatic colorectal cancer (mCRC) with the v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS) p.G13D mutation (an amino acid substitution at position 13 in KRAS from a glycine to an aspartic acid) and received cetuximab treatment had better clinical outcomes than patients who had mCRC tumors with KRAS codon 12 mutations.Methods: Relevant studies were identified by a search of MEDLINE, EMBASE, the Chinese Biomedical Database, and Wan Fang Digital Journals from inception to October 2011. The primary clinical outcomes included the objective response rate (ORR), progression-free survival (PFS), and overall survival (OS). The pooled relative risk (RR) or hazard ratio (HR) was estimated by using fixed-effects or random-effects models according to heterogeneity between studies.Results: Ten studies were considered eligible that included 1487 patients with mCRC. Patients who had tumors with the KRAS p.G13D mutation had a significantly higher ORR (10 studies; RR, 1.642; 95% confidence interval [CI], 1.131-2.384), longer PFS (1 study; HR, 0.54; 95% CI, 0.36-0.81), and longer OS (1 study; HR, 0.52; 95% CI, 0.33-0.80) than patients who had tumors with KRAS codon 12 mutations. Compared with patients who had KRAS wild-type tumors, patients with the p.G13D mutation had a significantly lower ORR (9 studies; RR, 0.540; 95% CI, 0.381-0.765) and nonsignificantly shorter PFS (1 study; HR, 0.99; 95% CI, 0.68-1.45) and OS (1 study; HR, 1.01; 95% CI, 0.66-1.54).Conclusions: Patients who had mCRC with the KRAS p.G13D mutation appeared to benefit more from cetuximab than patients who had tumors with KRAS codon 12 mutations. However, because of the limited sample sizes in the current meta-analysis, these results should be interpreted with caution. [ABSTRACT FROM AUTHOR]

In the title compound, C(18)H(18)FNO(3), the dihedral angles between the two benzene rings and the plane through the acrylate group and the fluoro-phenyl ring are 61.58 (8) and 13.33 (9)°, respectively. Mol-ecules are linked into ribbons through C-H⋯O and N-H⋯O hydrogen bonds, and further linked by C-H⋯π inter-actions, forming a three-dimensional network.