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All-inorganic cesium lead halide perovskite (CsPbX3, X = Cl, Br, and I) quantum dots (QDs), possessing high photoluminescence quantum yields and tunable color output, have recently been endowed great promise for high-performance solar cells and light-emitting diodes (LEDs). Although moisture stability has been greatly improved through separating QDs with a SiO2 shell, the practical applications of CsPbX3 QDs are severely restricted by their poor thermal stability, which is associated with the intrinsically low formation energies of perovskite lattices. In this regard, enhancing the formation energies of perovskite lattices of CsPbX3 QDs holds great promise in getting to the root of their poor thermal stability, which hitherto remains untouched. Herein, we demonstrate an effective strategy through Mn2+ substitution to fundamentally stabilize perovskite lattices of CsPbX3 QDs even at high temperatures up to 200 °C under ambient air conditions. We employ first-principle calculations to confirm that the significantly improved thermal stability and optical performance of CsPbX3:Mn2+ QDs arise primarily from the enhanced formation energy due to the successful doping of Mn2+ in CsPbX3 QDs. Benefiting from such an effective substitution strategy, these Mn2+-doped CsPbX3 QDs can function well as efficient light emitters toward the fabrication of high-performance perovskite LEDs. [ABSTRACT FROM AUTHOR]

Background: The aberrant expression of microRNA-140-5p (miR-140-5p) has been described in gastric cancer (GC). However, the role of miR-140-5p in GC remains unclear. In this study, the prognostic relevance of miR-140-5p in GC was investigated and YES1 was identified as a novel target of miR-140-5p in regulating tumor progression. Methods: miR-140-5p level was determined in 20 paired frozen specimens through quantitative real-time PCR, and analyzed in tissue microarrays through in situ hybridization. The target of miR-140-5p was verified through a dual luciferase reporter assay, and the effects of miR-140-5p on phenotypic changes in GC cells were investigated in vitro and in vivo. Results: Compared with that in adjacent normal tissues, miR-140-5p expression decreased in cancerous tissues. The downregulated miR-140-5p in 144 patients with GC was significantly correlated with the reduced overall survival of these patients. miR-140-5p could inhibit GC cell proliferation, migration and invasion by directly targeting 3′-untranlated region of YES1. miR-140-5p could also remarkably reduce the tumor size in GC xenograft mice. Conclusions: miR-140-5p serves as a potential prognostic factor in patients with GC, and miR-140-5p mediated YES1 inhibition is a novel mechanism behind the suppressive effects of miR-140-5p in GC. [ABSTRACT FROM AUTHOR]

Renal cell carcinoma (RCC) is a common type of kidney cancer. Normally, surgical treatment can prolong life, but only for patients with early stage tumors. However, it is difficult for early detection strategies to distinguish between benign and malignant kidney tumors. Therefore, potential biomarkers for early diagnosis and prognosis of RCC are needed. Intriguingly, mounting evidence has demonstrated that many long noncoding RNAs (lncRNAs) are strongly linked to cancers. Indeed, promising RCC-associated lncRNA biomarkers have also been identified. However, the functional and prognostic roles of the antisense (AS) serum deprivation response (SDPR) lncRNA (SDPR-AS) in RCC remain largely unknown. The aims of this study were to investigate the expression and prognostic relevance of SDPR-AS in RCC. We uncovered the downregulated expressions of both lncRNA SDPR-AS and its protein-coding gene, SDPR, in RCC tissues compared to the matched normal tissues. Furthermore, SDPR-AS and SDPR expressions were positively correlated. Overexpression and knockdown experiments suggested that SDPR-AS and SDPR were coregulated in RCC cell lines. In addition, overexpression of SDPR-AS suppressed cell migration and invasion, but not cell growth. Furthermore, expression of SDPR-AS was associated with tumor differentiation and lymphatic metastasis. Kaplan0-Meier survival and log-rank tests demonstrated the association of elevated expression of SDPR-AS with increased overall survival. In conclusion, our results suggest that the SDPR-AS may serve as a prognostic biomarker and therapeutic target of RCC. [ABSTRACT FROM AUTHOR]

We report lead-free single crystals with a nominal formula of (K0.45Na0.55)0.96Li0.04NbO3 grown using a simple low-cost seed-free solid-state crystal growth method (SFSSCG). The crystals thus prepared can reach maximum dimensions of 6mm × 5mm × 2mm and exhibit a large piezoelectric coefficient d33 of 689 pC/N. Moreover, the effective piezoelectric coefficient d33*, obtained under a unipolar electric field of 30 kV/cm, can reach 967 pm/V. The large piezoelectric response plus the high Curie temperature (TC) of 432 °C indicate that SFSSCG is an effective approach to synthesize high-performance lead-free piezoelectric single crystals. [ABSTRACT FROM AUTHOR]

Deregulation of Roundabout homolog 1 (Robo1) has been demonstrated to be associated with several types of human cancer, including gastric cancer. However, the detailed role of Robo1 and its regulatory mechanism in gastric cancer remain largely unclear. In the current study, it was demonstrated that the expression of microRNA (miR)-29a was frequently reduced in gastric cancer tissues, compared with their matched normal adjacent tissues. Similar results were additionally observed in AGS and SGC-7901 human gastric cancer cells. Overexpression of miR-29a led to reduced migration and invasion of AGS cells. To explore the targets of miR-29a in gastric cancer, bioinformatics analysis was conducted and Robo1 was identified as a putative target of miR-29a. Further western blotting and luciferase activity assay data confirmed that miR-29a was able to negatively regulate the protein expression of Robo1, through directly binding to the 3'-untranslated region of Robo1 mRNA in gastric cancer cells. In addition, it was demonstrated that Robo1 was frequently upregulated in gastric cancer tissues compared with their matched adjacent normal tissues, and a significant inverse correlation was identified between miR-29a and Robo1 expression. In addition, knockdown of Robo1 by small interfering RNA markedly inhibited the migratory and invasive capabilities of AGS cells, which the results obtained with overexpression of miR-29a. In conclusion, to the best of our knowledge the current study suggested for the first time, that miR-29a inhibits migration and invasion in part via direct inhibition of Robo1 in gastric cancer cells. Therefore, Robo1 and miR-29a may serve as diagnostic or therapeutic targets for gastric cancer. [ABSTRACT FROM AUTHOR]

Using tape-casting technology, 35 μm free-standing (100)-textured Li doped KNN (KNLN) thick film was prepared by employing NaNbO3 (NN) as template. It exhibited similar piezoelectric behavior to lead containing materials: a longitudinal piezoelectric coefficient (d33) of ~150 pm/V and an electromechanical coupling coefficient (kt) of 0.44. Based on this thick film, a 52 MHz side-looking miniature transducer with a bandwidth of 61.5% at -6 dB was built for Intravascular ultrasound (IVUS) imaging. In comparison with 40 MHz PMN-PT single crystal transducer, the rabbit aorta image had better resolution and higher noise-to-signal ratio, indicating that lead-free (100)-textured KNLN thick film may be suitable for IVUS (>50 MHz) imaging. [ABSTRACT FROM AUTHOR]

The Aurivillius oxide family possessess various attractive physical properties and have been commercially applicable in many areas. The regular large-period phases of this family are believed to offer better flexibilities of performance optimization than the commercial ones. However, the experimental synthesis of them is still challenging and the physical mechanisms of their structural stability are not yet clear. We propose a quasi-binary solid solution approach to study the structural stability of Aurivillius phases based on ab initio calculations. Three typical homologous series, CaBi2Nam-2NbmO3m+3 and Mm-3Bi4TimO3m+3 (M=Ca, Sr) with different in-plane lattice mismatches and chemical compositions, are studied. Our results prove that all the three systems are thermodynamically stable up to m=7 phases. By decomposing the formation process into two separate steps and analyzing the contributions to Gibbs formation energy from different factors, the configurational entropy as well as chemical bond optimization is suggested to play a crucial role in stabilizing the final phases, together with the elastic effect that was solely considered as the dominant factor before. [ABSTRACT FROM AUTHOR]

Background: Thrombospondins (THBSs) are a family of multidomain and secreted matricellular Ca2+-binding glycoproteins which has at least five members encoded by independent genes. As a THBSs family member, Thrombospondin2 (THBS2) has been reported to regulate angiogenesis. Nevertheless, the functions and clinical significance of THBS2 still remains unclear in gastric cancer. Methods: The mRNA and protein expression levels of THBS2 were assessed in 14 paired of gastric cancer specimens and corresponding normal mucosas using quantitative real-time PCR and western blot analysis. Immunohistochemistry of THBS2 and CD34 on population-based tissue microarrays consisting of 129 gastric cancer cases were used to evaluate the prognostic significance of THBS2 and microvessel density (MVD) of each sample. Survival analyses were performed by Kaplan–Meier method and Cox's proportional hazards model. Colony formation assay, endothelial cell tube formation assay, cell migration assay and apoptosis analysis in MKN-45 and SGC-7901 cell lines were carried out to evaluate the effects of THBS2 on gastric cancer in vitro. Results: 85.71% (12 of 14) gastric cancer tissues expressed remarkably lower THBS2 in both mRNA and protein levels than the corresponding normal controls. Consistently, tissue microarray (TMA) results showed THBS2 levels were also inhibited in gastric cancer tissues compared with the normal controls. Moreover, we observed that patients with higher levels of THBS2 were significantly correlated with more favourable prognosis while decreased THBS2 expression were associated with poorer histological grades of gastric cancer. Additionally, our in vitro experiments further demonstrated that overexpression of THBS2 could impede both the proliferation rate and the tube formation of Human umbilical vein endothelial cells (HUVECs) in MKN-45 and SGC-7901 cell lines. Conclusion: Our study suggests THBS2 is aberrantly expressed in gastric cancer and plays a critical role in cancer progression, which can be a potential prognosis predictor of gastric cancer. [ABSTRACT FROM AUTHOR]

Increasing seed yield and quality of key cool-season perennial grasses is an important component of meeting China's environmental, food security, and urban beautification goals. Determining a suitable seed producing region and developing best management practices for this region with specific, high priority grasses will contribute to the availability of seed for reducing desertification, increasing livestock production, and improving urban living conditions. Previous research in other areas has addressed various agronomic practices on some grasses, but none has evaluated optimal row spacings for producing high yields of high quality seed in conditions similar to the Hexi Corridor, currently a major seed producing area in China for other seed crops. We compared our field trials in this area with those of other regions in China and the world to determine if this area would be suitable as a grass seed production center. Five important perennial, cool-season grasses {[Elymus kamoji (ohwi) S.L. Chen, slender wheatgrass [Elymus trachycaulus (Link) Gould ex Shinners ssp. Trachycaulus], smooth bromegrass (Bromus inermis Leyss), Siberian wildrye (Elymus sibiricus L.), and Chinese sheepgrass [Leymus chinensis (Trin) Tzvel]} were evaluated from 2010 to 2012 under four row spacing treatments (30, 50, 70, and 90 cm). Results showed all five grasses have potential for high seed production in this region, with yields equivalent to or significantly higher than other areas. Optimal row spacing for Elymus kamoji and smooth bromegrass was 30 cm while a 50 cm row spacing was better for seed production and weed control for slender wheatgrass, Siberian wildrye, and Chinese sheepgrass. This work will allow multinational seed companies, development agencies, and government program directors to better evaluate the potential economic sustainability of grass seed production in this region compared to importing seed from other regions of the world. [ABSTRACT FROM AUTHOR]

Chloroquine (CQ) and other quinoline-containing antimalarials are important drugs with many therapeutic benefits as well as adverse effects. However, the molecular targets underlying most such effects are largely unknown. By taking a novel functional genomics strategy, which employs a unique combination of genome-wide drug-gene synthetic lethality (DGSL), gene-gene synthetic lethality (GGSL), and dosage suppression (DS) screens in the model organism Saccharomyces cerevisiae and is thus termed SL/DS for simplicity, we found that CQ inhibits the thiamine transporters Thi7, Nrt1, and Thi72 in yeast. We first discovered a thi3Δ mutant as hypersensitive to CQ using a genome-wide DGSL analysis. Using genome-wide GGSL and DS screens, we then found that a thi7Δ mutation confers severe growth defect in the thi3Δ mutant and that THI7 overexpression suppresses CQ-hypersensitivity of this mutant. We subsequently showed that CQ inhibits the functions of Thi7 and its homologues Nrt1 and Thi72. In particular, the transporter activity of wild-type Thi7 but not a CQ-resistant mutant (Thi7 T287N) was completely inhibited by the drug. Similar effects were also observed with other quinoline-containing antimalarials. In addition, CQ completely inhibited a human thiamine transporter (SLC19A3) expressed in yeast and significantly inhibited thiamine uptake in cultured human cell lines. Therefore, inhibition of thiamine uptake is a conserved mechanism of action of CQ. This study also demonstrated SL/DS as a uniquely effective methodology for discovering drug targets. [ABSTRACT FROM AUTHOR]

AbstractObesity, the metabolic syndrome, and aging share several pathogenic features in both humans and non-human primates, including insulin resistance and inflammation. Since muscle and liver are considered key integrators of metabolism, we sought to determine in biopsies from lean and obese aging rhesus monkeys the nature of defects in insulin activation and, further, the potential for mitigation of such defects by an in vivoinsulin sensitizer, rosiglitazone, and a thiazolidinedione activator of the peroxisome proliferator-activated receptor gamma. The peroxisome proliferator-activated receptor gamma agonist reduced hyperinsulinemia, improved insulin sensitivity, lowered plasma triglycerides and free fatty acids, and increased plasma adiponectin. In muscle of obese monkeys, previously shown to exhibit defective insulin signaling, the insulin sensitizer improved insulin activation of atypical protein kinase C (aPKC), the defective direct activation of aPKC by phosphatidylinositol (PI)-3,4,5-(PO4)3, and 5′-AMP-activated protein kinase and increased carnitine palmitoyltransferase-1 mRNA expression, but it did not improve insulin activation of insulin receptor substrate (IRS)-1-dependent PI 3-kinase (IRS-1/PI3K), protein kinase B, or glycogen synthase. We found that, although insulin signaling was impaired in muscle, insulin activation of IRS-1/PI3K, IRS-2/PI3K, protein kinase B, and aPKC was largely intact in liver and that rosiglitazone improved insulin signaling to aPKC in muscle by improving responsiveness to PI-3,4,5-(PO4)3. Antioxid. Redox Signal.14, 207–219. [ABSTRACT FROM AUTHOR]

The effect of B2O3–SiO2 liquid-phase additives on the sintering, microstructure, and microwave dielectric properties of LiNb0.63Ti0.4625O3 ceramics was investigated. It was found that the sintering temperature could be lowered easily, and the densification and dielectric properties of LiNb0.63Ti0.4625O3 ceramics could be greatly improved by adding a small amount of B2O3–SiO2 solution additives. No secondary phase was observed for the ceramics with B2O3–SiO2 additives. With the addition of 0.10 wt% B2O3–SiO2, the ceramics sintered at 900°C showed favorable microwave dielectric properties with ℇr=71.7, Q× f=4950 GHz, and τf=−2.1 ppm/°C. The energy dispersive spectra analysis showed an excellent co-firing interfacial behavior between the LiNb0.63Ti0.4625O3 ceramic and the Ag electrode. It indicated that LiNb0.63Ti0.4625O3 ceramics with B2O3–SiO2 solution additives have a number of potential applications on passive integrated devices based on the low-temperature co-fired ceramics technology. [ABSTRACT FROM AUTHOR]

The 8.2 ka cooling event was an abrupt, widespread climate instability. There is general consensus that the episode was likely initiated by a catastrophic outflow of proglacial Lakes Agassiz and Ojibway through the Hudson Strait, with subsequent disruption of the Atlantic meridional overturning circulation. However, the total discharge and flux during the 8.2 ka event remain uncertain. We compute the sea-level signature, or "fingerprint," associated with the drainage of Lakes Agassiz and Ojibway, as well as the expected sea-level signal over the same time period due to glacial isostatic adjustment (GIA) in response to the Late Pleistocene deglaciation. Our analysis demonstrates that sites relatively close to the lakes, including the West and Gulf Coasts of the United States, have small signals due to the lake release and potentially large GIA signals, and thus they may not be optimal fi eld sites for constraining the outflow volume. Other sites, such as the east coast of South America and western Africa, have signifi cantly larger signals associated with the lake release and are thus better choices in this regard. [ABSTRACT FROM AUTHOR]

Upconversion emission properties of Na1/2Bi1/2TiO3:Er3+ ceramics prepared by the solid-state reaction method were analyzed as a function of Er3+ concentration and incident pump power. Strong green (550 nm) and red (670 nm) emission bands were observed with 980 nm excitation at room temperature. Experimental results showed that the emission bands can be tuned by changing Er3+ concentration. Upconversion processes in these samples result from not only a two-photon excited-state absorption process but also a nonradiative energy transfer and cross-relaxation process. [ABSTRACT FROM AUTHOR]

Although several randomized controlled trials have been published in recent years, the effect of perioperative immunonutrition in esophageal cancer (EC) patients remains unclear. This initial meta-analysis was conducted to assess whether perioperative enteral immunonutrition reduces postoperative complications in patients undergoing esophagectomy for EC. Relevant randomized controlled trials published before 1st September 2019 were retrieved from the Cochrane Library, PubMed, and EMBASE databases. After the literature was screened, two researchers extracted the information and data from eligible studies according to predefined selection criteria. Obtained data were pooled and analyzed by RevMan 5.3 software. The results were presented as risk ratios (RRs) with 95% confidence intervals (CIs). The heterogeneity among studies was tested by I2 test. Seven high-quality randomized controlled trials were included, with a total of 606 patients, 311 of whom received immunonutrition before and after surgery, while 295 received perioperative standard nutrition. No significant difference was observed between the two groups in the incidence of postoperative infection complications, including total infection complications (RR = 0.97, CI: 0.78–1.20, P =  0.76), pneumonia (RR = 0.97, CI: 0.71–1.33, P =  0.84), wound infection (RR = 0.80, CI: 0.46–1.40, P =  0.44), sepsis (RR = 1.35, CI: 0.67–2.71, P =  0.40), and urinary tract infection (RR = 0.87, CI: 0.54–1.40, P =  0.56). The prevalence of anastomotic leakage in the two groups was 9.4 and 5.4%, but the difference was not statistically significant (RR = 0.59, CI: 0.33–1.04, P =  0.07). Perioperative enteral immunonutrition provided no benefit in terms of the incidence of infection complications and anastomotic leakage in EC patients undergoing esophagectomy. Further large-scale randomized controlled trials are needed to confirm this conclusion. [ABSTRACT FROM AUTHOR]