▶ In this article, we synthesized flower-like ZnO nanorods on substrates by a simple thermal evaporation process without any catalysts or templates. ▶ The PL spectrum showed that a sharp and strong ...UV emission band located at 386
nm together with a weak and suppressed yellow–green emission band. ▶ The high intensity ratio of the UV peak to the defect emissions indicates fairly good crystallization of flower-like ZnO nanorods. ▶ The Zn liquid droplets function as catalyst plays an important role in the self-catalytic VLS growth process of flower-like ZnO nanorods at low temperature deposition region. ▶ The possible growth mechanism of these structures is investigated.
Flower-like ZnO nanorods have been synthesized by heating a mixture of ZnO/graphite powders using the thermal evaporation and vapor transport on Si (1
0
0) substrates without any catalyst. The structures, morphologies and optical properties of the products were characterized in detail by using X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), photoluminescence (PL) and Raman spectroscopy. The synthesized products consisted of large quantities of flower-like ZnO nanostructures in the form of uniform nanorods. The flower-like ZnO nanorods had high purity and well crystallized wurtzite structure, whose high crystalline quality was proved by Raman spectroscopy. The as-synthesized flower-like ZnO nanorods showed a strong ultraviolet emission at 386
nm and a weak and broad yellow–green emission in visible spectrum in its room temperature photoluminescence (PL) spectrum. In addition, the growth mechanism of the flower-like ZnO nanorods was discussed based on the reaction conditions.
Ultralight Metallic Microlattices Schaedler, T. A.; Jacobsen, A. J.; Torrents, A. ...
Science (American Association for the Advancement of Science),
11/2011, Volume:
334, Issue:
6058
Journal Article
Peer reviewed
Ultralight (< 10 milligrams per cubic centimeter) cellular materials are desirable for thermal insulation; battery electrodes; catalyst supports; and acoustic, vibration, or shock energy damping. We ...present ultralight materials based on periodic hollow-tube microlattices. These materials are fabricated by starting with a template formed by self-propagating photopolymer waveguide prototyping, coating the template by electroless nickel plating, and subsequently etching away the template. The resulting metallic microlattices exhibit densities ρ > 0.9 milligram per cubic centimeter, complete recovery after compression exceeding 50% strain, and energy absorption similar to elastomers. Young's modulus Å scales with density as E ~ p², in contrast to the £ ~ p³ scaling observed for ultralight aerogels and carbon nanotube foams with stochastic architecture. We attribute these properties to structural hierarchy at the nanometer, micrometer, and millimeter scales.
Various factors and cellular components in the tumor microenvironment are key drivers associated with drug resistance in many cancers. Here, we analyzed the factors and molecular mechanisms involved ...in chemoresistance in patients with esophageal squamous cell carcinoma (ESCC). We found that interleukin 6 (IL6) derived mainly from cancer-associated fibroblasts played the most important role in chemoresistance by upregulating C-X-C motif chemokine receptor 7 (CXCR7) expression through signal transducer and activator of transcription 3/nuclear factor-κB pathway. CXCR7 knockdown resulted in the inhibition of IL6-induced proliferation and chemoresistance. In addition, CXCR7 silencing significantly decreased gene expression associated with stemness, chemoresistance and epithelial-mesenchymal transition and suppressed the proliferation ability of ESCC cells in three-dimensional culture systems and angiogenesis assay. In clinical samples, ESCC patients with high expression of CXCR7 and IL6 presented a significantly worse overall survival and progression-free survival upon receiving cisplatin after operation. These results suggest that the IL6-CXCR7 axis may provide a promising target for the treatment of ESCC.
Objectif Évaluer l’impact économique des bénéfices thérapeutiques associés à l’addition par étapes (APE) d’insuline asparte (IAsp) au moment des repas, aux États-Unis (EU). Patients et méthodes ...Full ?STEP™ est un essai clinique démontrant que l’intensification du traitement du diabète de type 2 (DT2) par APE d’IAsp au moment des repas vs l’introduction d’emblée d’insuline en 3 bolus/jur (basal-bolus complet BBC), diminue les épisodes d’hypoglycémie, avec une réduction d’HbA1c comparable. Les données sur les coûts ont été extraites de la littérature, exprimées en dollars US et réduites à 3,5 % par an. L’impact médico-économique avec et sans APE d’IAsp a été évalué chaque année, et extrapolé sur 5 ans. Résultats L’APE d’IAsp réduisait les épisodes d’hypoglycémie sévères de 45,0 % la première année. En considérant que la prévalence du DT2 est de 7,8 %, dont 10,1 % initient un schéma BBC chaque année, un plan de santé visant 1 million de patients permettraient d’économiser plus de 11 millions de dollars la première année, et 75 la cinquième année, en utilisant l’APE d’IAsp à la place de l’insuline BBC. Ces économies correspondraient à 0,95 et 1,27 dollars par individu et par mois, respectivement. La réduction des épisodes d’hypoglycémie diminuerait les coûts de 17,9 millions de dollars sur 5 ans, avec une économie de 6,2 millions provenant de la réduction des épisodes d’hypoglycémie sévères. Conclusion Selon les données de Full ?STEP™, l’APE d’IAsp offre des bénéfices économiques et réduit les épisodes d’hypoglycémie vs. l’insuline BBC dans le cadre de l’intensification du traitement du DT2.
What Is Known and Objective. To reevaluate the benefits and risks of corticosteroid treatment in adult patients with septic shock. Methods. This study was performed based on PRISMA guidelines. ...Randomized controlled trials (RCTs) of corticosteroids versus placebo were retrieved from PubMed, MEDLINE, EMBASE, Web of Science, the Cochrane Central RCTs, and ClinicalTrials.gov from January 1980 to April 2018. We also conducted a trial sequential analysis to indicate the possibility of type I or II errors and calculate the information size. Grading of Recommendations, Assessment, Development and Evaluation approach (GRADE) was applying to assess the certainty of evidence at the primary outcome level. Results. Twenty-one RCTs were identified and analyzed. Patients treated with corticosteroid had a 7% reduction in relative risk in 28-day all-cause mortality compared to controls (RR 0.93, 95% CI 0.88 to 0.99). However, there were no significant differences for the intensive care unit (ICU) mortality (RR 0.97, 95% CI 0.86 to 1.09) or in-hospital mortality (RR 1.01, 95% CI 0.92 to 1.11). Corticosteroids shortened the length of ICU stay by 1.04 days (RR -1.04, 95% CI -1.72 to -0.36) and the length of hospital stay by 2.49 days (RR -2.49, 95% CI -4.96 to -0.02). Corticosteroids increased the risk of hyperglycemia (RR 1.11, 95% CI 1.06 to 1.16) but not gastroduodenal bleeding (RR 1.06, 95% CI 0.82 to 1.37) or superinfection (RR 1.04, 95% CI 0.94 to 1.15). However, some date on secondary outcomes were unavailable because they were not measured or not reported in the included studies which may cause a lack of power or selective outcome reporting. The information size was calculated at 10044 patients. Trial sequential analysis showed that the meta-analysis was conclusive and the risk of type 2 error was minimal. What Is New and Conclusion. Corticosteroids are likely to be effective in reducing 28-day mortality and attenuating septic shock without increasing the rate of life-threatening complications. TSA showed that the risk of type II error in this meta-analysis was minimal and the result was conclusive.
Runx2, a bone-specific transcriptional regulator, is abnormally expressed in highly metastatic prostate cancer cells. Here, we identified the functional activities of Runx2 in facilitating tumor ...growth and osteolysis. Our studies show that negligible Runx2 is found in normal prostate epithelial and non-metastatic LNCaP prostate cancer cells. In the intra-tibial metastasis model, high Runx2 levels are associated with development of large tumors, increased expression of metastasis-related genes (MMP9, MMP13, VEGF, Osteopontin) and secreted bone-resorbing factors (PTHrP, IL8) promoting osteolytic disease. Runx2 siRNA treatment of PC3 cells decreased cell migration and invasion through Matrigel in vitro, and in vivo shRunx2 expression in PC3 cells blocked their ability to survive in the bone microenvironment. Mechanisms of Runx2 function were identified in co-culture studies showing that PC3 cells promote osteoclastogenesis and inhibit osteoblast activity. The clinical significance of these findings is supported by human tissue microarray studies of prostate tumors at stages of cancer progression, in which Runx2 is expressed in both adenocarcinomas and metastatic tumors. Together these findings indicate that Runx2 is a key regulator of events associated with prostate cancer metastatic bone disease.
► Rare earth element Y was doped in ZnO nanoparticles and the saturation concentration of Y in ZnO lattice is 6.12at%. ► The UV emission of ZnO can be significantly increased by Y doping in ZnO ...lattice. ► The deep level emission of ZnO was suppressed by Y doping and a high intensity ratio (32) of UV to DLE was obtained.
Y-doped ZnO (Zn1−xYxO) nanoparticles with different Y concentrations were synthesized by sol–gel method. The effects of Y concentration on the optical properties of the as-synthesized Zn1−xYxO nanoparticles were investigated. Photoluminescence (PL) measurements revealed that doping of Y in ZnO induced an evidence increase of UV emission. At Y concentration x=0.07, the UV emission intensity reached maximum, which is about 9 times higher than that of the compared pure ZnO nanoparticles. Exceeding this concentration, the formation of Y2O3 causes a decrease in the UV emission intensity. This enhanced UV emission enables Zn1−xYxO system potential applications in supersensitive UV detector sinimaging, photosensing, and intrachip optical interconnects.
Cellular senescence is a known driver of carcinogenesis and age-related diseases, yet senescence is required for various physiological processes. However, the mechanisms and factors that control the ...negative effects of senescence while retaining its benefits are still elusive. Here, we show that the rasGAP SH3-binding protein 1 (G3BP1) is required for the activation of the senescent-associated secretory phenotype (SASP). During senescence, G3BP1 achieves this effect by promoting the association of the cyclic GMP-AMP synthase (cGAS) with cytosolic chromatin fragments. In turn, G3BP1, through cGAS, activates the NF-κB and STAT3 pathways, promoting SASP expression and secretion. G3BP1 depletion or pharmacological inhibition impairs the cGAS-pathway preventing the expression of SASP factors without affecting cell commitment to senescence. These SASPless senescent cells impair senescence-mediated growth of cancer cells in vitro and tumor growth in vivo. Our data reveal that G3BP1 is required for SASP expression and that SASP secretion is a primary mediator of senescence-associated tumor growth.
ABSTRACT
We use the first release of the SDSS/MaStar stellar library comprising ∼9000, high S/N spectra, to calculate integrated spectra of stellar population models. The models extend over the ...wavelength range 0.36–1.03 µm and share the same spectral resolution ($R\sim 1800$) and flux calibration as the SDSS-IV/MaNGA galaxy data. The parameter space covered by the stellar spectra collected thus far allows the calculation of models with ages and chemical composition in the range $\rm {\mathit{ t}\gt 200 \,Myr, -2 \lt = Z/H \lt = + 0.35}$, which will be extended as MaStar proceeds. Notably, the models include spectra for dwarf main-sequence stars close to the core H-burning limit, as well as spectra for cold, metal-rich giants. Both stellar types are crucial for modelling λ > 0.7 µm absorption spectra. Moreover, a better parameter coverage at low metallicity allows the calculation of models as young as 500 Myr and the full account of the blue horizontal branch phase of old populations. We present models adopting two independent sets of stellar parameters (Teff, log g, Z/H). In a novel approach, their reliability is tested ‘on the fly’ using the stellar population models themselves. We perform tests with Milky Way and Magellanic Clouds globular clusters, finding that the new models recover their ages and metallicities remarkably well, with systematics as low as a few per cent for homogeneous calibration sets. We also fit a MaNGA galaxy spectrum, finding residuals of the order of a few per cent comparable to the state-of-art models, but now over a wider wavelength range.
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