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排序方式: 共有901条查询结果,搜索用时 31 毫秒
891.
Luz M. Ballesteros Santiago Martín Javier Corts Santiago Marqus‐Gonzlez Francesc Prez‐Murano Richard J. Nichols Paul J. Low Pilar Cea 《Advanced Materials Interfaces》2014,1(9)
In this contribution, a novel method for practical uses in the fabrication of the top contact electrode in a metal/organic monolayer/metal device is presented. The procedure involves the thermally induced decomposition of an organometallic compound, abbreviated as the TIDOC method. Monolayers incorporating the metal organic compounds (MOCs) [[4‐{(4‐carboxy)ethynyl}phenyl]ethynyl]‐(triphenylphosphine)‐gold, 1, or [1‐isocyano‐4‐methoxybenzene]‐[4‐amino‐phenylethynyl]‐gold, 2, were annealed at moderate temperatures (1: 150 °C for 2h and 2: 100 °C for 2 h), resulting in cleavage of the Au‐P or Au‐C bond and reduction of Au(I) to Au(0) as metallic gold nanoparticles (GNPs). These particles are distributed on the surface of the film resulting in formation of metal/molecule/GNP sandwich structures. Electrical properties of these nascent devices were determined by recording I–V curves with a conductive‐AFM. The I–V curves collected from these metal/organic monolayer/GNPs sandwich structures are typical of metal‐molecule‐metal junctions, with no low resistance traces characteristic of metallic short circuits observed over a wide range of set‐point forces. The TIDOC method is therefore an effective procedure for the fabrication of molecular junctions for the emerging area of molecular electronics. 相似文献
892.
Chong Guan Low Qing Zhang Rodney S. Ruoff 《Small (Weinheim an der Bergstrasse, Germany)》2014,10(20):4213-4218
Chemical vapor deposited monolayer graphene is transferred onto atomically flat and ultra‐thin muscovite mica to study the transport characteristics of graphene with a test structure of mica‐based graphene field effect transistor (GFET). The transfer curve of the 24 nm mica‐based GFET shows an effective carrier mobility of 2748 cm2/Vs and a transconductance of 3.36 μS, a factor of 2 and 7 larger than those values obtained from 40 nm SiO2 based GFET, respectively. The results demonstrate that mica is an excellent gate dielectric material due to its high dielectric constant, high dielectric strength, and atomically flat surface. 相似文献
893.
Zhouyou Wang Ze-Xian Low Xiangkang Zeng Bin Su Yichun Yin Chenghua Sun Tim Williams Huanting Wang Xiwang Zhang 《International Journal of Hydrogen Energy》2018,43(3):1508-1515
TiO2 nanosheets with high ratio of {001} facets were coupled with reduced graphene oxide (rGO) nanosheets through the link of silver (Ag) nanoparticles, forming a novel ternary nanocomposite photocatalyst with a vertical heterostructure, TiO2-Ag-rGO. The vertical anchoring of TiO2-Ag nanosheets between rGO sheets was confirmed by transmission electron microscopy (TEM), Raman spectroscopy, energy dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). Due to excellent separation of electron-hole pairs in the TiO2 nanosheets, enhanced electron transfer to rGO via Ag nanoparticles, the TiO2-Ag-rGO nanocomposite exhibited an outstanding performance in photocatalytic hydrogen production, with a hydrogen production rate of 593.56 μmol g?1 h?1. This study provides new insights to the development of Pt-free photocatalysts for hydrogen production. 相似文献
894.
The Associations Between Oral Complex Carbohydrate Sensitivity,BMI, Liking,and Consumption of Complex Carbohydrate Based Foods 下载免费PDF全文
Recent work suggests that humans may perceive complex carbohydrates and that their sensitivity to simple carbohydrates (i.e., glucose and sucrose) is independent from tasting complex carbohydrates. The aim of this study was to confirm whether humans could sense complex carbohydrates from a range of concentration levels; and if their oral sensitivity to complex carbohydrate relates to their BMI, liking, and consumption of complex carbohydrate‐based foods using a large sample group of adults. Participants’ (n = 92 females, age 23.7 ± 0.5 yr [range, 19 to 47 yr]) oral sensitivity towards complex carbohydrate (maltodextrin) and sweet taste function (glucose) was assessed by measuring detection threshold and suprathreshold intensity perception (gLMS). Participants were asked to complete an online version of a Food Frequency Questionnaire and a Likes and Dislikes Questionnaire. Hedonic ratings for complex carbohydrate and sweet solutions, as well as for a range of complex carbohydrate and sweet prototypical foods, were also measured. Consistent with previous findings, there was large interindividual variation in detection and intensity measures for maltodextrin and glucose. No significant associations were found between oral complex carbohydrate sensitivity, Body Mass Index (BMI), and frequency of consumption of complex carbohydrate‐based foods measured. Similarly, no differences were observed between liking of complex carbohydrates, BMI, and food intake. All in, these results from a large sample group further support the proposition that complex carbohydrates are not invisible to the human palate, and can be sensed in the oral cavity even at low concentration levels. 相似文献
895.
G. Beydoun G. Low H. Mouratidis B. Henderson-Sellers 《Information and Software Technology》2009,51(5):832-845
This paper adopts a model-based security (MBS) approach to identify security requirements during the early stages of multi-agent system development. Our adopted MBS approach is underpinned by a metamodel independent of any specific methodology. It allows for security considerations to be embedded within any situated agent methodology which then prescribes security considerations within its work products. Using a standard model-driven engineering (MDE) approach, these work products are initially constructed as high abstraction models and then transformed into more precise models until code-specific models can be produced. A multi-agent system case study is used to illustrate the applicability of the proposed security-aware metamodel. 相似文献
896.
Ilaria Bestetti Milena Crippa Alessandra Sironi Francesca Tumiatti Maura Masciadri Marie Falkenberg Smeland Swati Naik Oliver Murch Maria Teresa Bonati Alice Spano Elisa Cattaneo Milena Mariani Fabio Gotta Francesca Crosti Pietro Cavalli Chiara Pantaleoni Federica Natacci Maria Francesca Bedeschi Donatella Milani Silvia Maitz Angelo Selicorni Luigina Spaccini Angela Peron Silvia Russo Lidia Larizza Karen Low Palma Finelli 《International journal of molecular sciences》2022,23(11)
KBG syndrome (KBGS) is a neurodevelopmental disorder caused by the Ankyrin Repeat Domain 11 (ANKRD11) haploinsufficiency. Here, we report the molecular investigations performed on a cohort of 33 individuals with KBGS clinical suspicion. By using a multi-testing genomic approach, including gene sequencing, Chromosome Microarray Analysis (CMA), and RT-qPCR gene expression assay, we searched for pathogenic alterations in ANKRD11. A molecular diagnosis was obtained in 22 out of 33 patients (67%). ANKRD11 sequencing disclosed pathogenic or likely pathogenic variants in 18 out of 33 patients. CMA identified one full and one terminal ANKRD11 pathogenic deletions, and one partial duplication and one intronic microdeletion, with both possibly being pathogenic. The pathogenic effect was established by RT-qPCR, which confirmed ANKRD11 haploinsufficiency only for the three deletions. Moreover, RT-qPCR applied to six molecularly unsolved KBGS patients identified gene downregulation in a clinically typical patient with previous negative tests, and further molecular investigations revealed a cryptic deletion involving the gene promoter. In conclusion, ANKRD11 pathogenic variants could also involve the regulatory regions of the gene. Moreover, the application of a multi-test approach along with the innovative use of RT-qPCR improved the diagnostic yield in KBGS suspected patients. 相似文献
897.
Larsen Alessandro Kat-Jun Eric Low Aisha Abushelaibi Swee-Hua Erin Lim Wan-Hee Cheng Sook-keng Chang Kok-Song Lai Yap Wai Sum Sathiya Maran 《International journal of molecular sciences》2022,23(22)
The diagnosis of endometrial cancer involves sequential, invasive tests to assess the thickness of the endometrium by a transvaginal ultrasound scan. In 6–33% of cases, endometrial biopsy results in inadequate tissue for a conclusive pathological diagnosis and 6% of postmenopausal women with non-diagnostic specimens are later discovered to have severe endometrial lesions. Thus, identifying diagnostic biomarkers could offer a non-invasive diagnosis for community or home-based triage of symptomatic or asymptomatic women. Herein, this study identified high-risk pathogenic nsSNPs in the NRAS gene. The nsSNPs of NRAS were retrieved from the NCBI database. PROVEAN, SIFT, PolyPhen-2, SNPs&GO, PhD-SNP and PANTHER were used to predict the pathogenicity of the nsSNPs. Eleven nsSNPs were identified as “damaging”, and further stability analysis using I-Mutant 2.0 and MutPred 2 indicated eight nsSNPs to cause decreased stability (DDG scores < −0.5). Post-translational modification and protein–protein interactions (PPI) analysis showed putative phosphorylation sites. The PPI network indicated a GFR-MAPK signalling pathway with higher node degrees that were further evaluated for drug targets. The P34L, G12C and Y64D showed significantly lower binding affinity towards GTP than wild-type. Furthermore, the Kaplan–Meier bioinformatics analyses indicated that the NRAS gene deregulation affected the overall survival rate of patients with endometrial cancer, leading to prognostic significance. Findings from this could be considered novel diagnostic and therapeutic markers. 相似文献
898.
Nicole Dmochowska Valentina Milanova Ramesh Mukkamala Kwok Keung Chow Nguyen T. H. Pham Madduri Srinivasarao Lisa M. Ebert Timothy Stait-Gardner Hien Le Anil Shetty Melanie Nelson Philip S. Low Benjamin Thierry 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(21):2204956
Accurate delineation of gross tumor volumes remains a barrier to radiotherapy dose escalation and boost dosing in the treatment of solid tumors, such as prostate cancer. Magnetic resonance imaging (MRI) of tumor targets has the power to enable focal dose boosting, particularly when combined with technological advances such as MRI-linear accelerator. Fibroblast activation protein (FAP) is overexpressed in stromal components of >90% of epithelial carcinomas. Herein, the authors compare targeted MRI of prostate specific membrane antigen (PSMA) with FAP in the delineation of orthotopic prostate tumors. Control, FAP, and PSMA-targeting iron oxide nanoparticles were prepared with modification of a lymphotropic MRI agent (FerroTrace, Ferronova). Mice with orthotopic LNCaP tumors underwent MRI 24 h after intravenous injection of nanoparticles. FAP and PSMA nanoparticles produced contrast enhancement on MRI when compared to control nanoparticles. FAP-targeted MRI increased the proportion of tumor contrast-enhancing black pixels by 13%, compared to PSMA. Analysis of changes in R2 values between healthy prostates and LNCaP tumors indicated an increase in contrast-enhancing pixels in the tumor border of 15% when targeting FAP, compared to PSMA. This study demonstrates the preclinical feasibility of PSMA and FAP-targeted MRI which can enable targeted image-guided focal therapy of localized prostate cancer. 相似文献
899.
Low John M. Haszeldine R. Stuart Harrison Gareth P. 《Clean Technologies and Environmental Policy》2023,25(3):757-770
Clean Technologies and Environmental Policy - Decarbonisation of transport emissions is essential to meet climate targets. For road transport, currently available technologies are battery electric... 相似文献
900.