226 research outputs found
Effects of Laser Surface Melting on Ti 30Nb 2Sn Sintered Alloy
[EN] Laser surface melting (LSM) is used to simultaneously melt a thin layer and quench TiÂż30NbÂż2Sn substrate produced by powder metallurgy route. Results show LSM is useful to eliminate non-desirable open porosity and to reduce even more the Young Modulus. The best microstructure is achieved below the melting pool where high peak temperature combined with high cooling rate during laser processing is present. LSM retains beta titanium without traces of martensite or grain boundary alpha due to oxygen contamination.This work is financially supported by Spanish Ministry of Science (Grant No. MAT2011-28492-C03-01 and BES-2009-013589) and PIB2010BZ-00448 International project.Candel Bou, JJ.; Amado, JM.; AmigĂł, V.; Tobar, MJ. (2017). Effects of Laser Surface Melting on Ti 30Nb 2Sn Sintered Alloy. Advanced Engineering Materials. 19(6):1500640-1-1500640-4. doi:10.1002/adem.201500640S1500640-11500640-419
Simultaneous determination of caffeic acid and rosmarinic acid in Ziziphora clinopodioides Lam. from different sources in Xinjiang by a novel rapid resolution liquid chromatography method
A simple and sensitive rapid resolution liquid chromatography method with a short run time was developed for the simultaneous determination of caffeic acid and rosmarinic acid in Ziziphora clinopodioides Lam. A good chromatographic separation was obtained on an XDB-C18 reversed-phase analytical column (50 mm Ă 4.6 mm, 1.8 ÎŒm) by gradient elution with methanol and water containing 1 % acetic acid (v/v) at 0.9 mL/min flow rate. The detection wavelength was set at 330 nm. The mean recoveries of the two compounds were 101.6 % for caffeic acid and 104.2 % for rosmarinic acid. The method was successfully applied to determine the two compounds in 10 Z. clinopodioides Lam. samples of different origins. A significant variation in the contents of the two compounds among the 10 samples was observed. Therefore, this method provides a new basis for the overall routine quality control assessment of Z. clinopodioides Lam.Colegio de FarmacĂ©uticos de la Provincia de Buenos Aire
QSpike tools: a generic framework for parallel batch preprocessing of extracellular neuronal signals recorded by substrate microelectrode arrays
Micro-Electrode Arrays (MEAs) have emerged as a mature technique to investigate brain (dys)functions in vivo and in in vitro animal models. Often referred to as âsmartâ Petri dishes, MEAs have demonstrated a great potential particularly for medium-throughput studies in vitro, both in academic and pharmaceutical industrial contexts. Enabling rapid comparison of ionic/pharmacological/genetic manipulations with control conditions, MEAs are employed to screen compounds by monitoring non-invasively the spontaneous and evoked neuronal electrical activity in longitudinal studies, with relatively inexpensive equipment. However, in order to acquire sufficient statistical significance, recordings last up to tens of minutes and generate large amount of raw data (e.g., 60 channels/MEA, 16 bits A/D conversion, 20 kHz sampling rate: approximately 8 GB/MEA,h uncompressed). Thus, when the experimental conditions to be tested are numerous, the availability of fast, standardized, and automated signal preprocessing becomes pivotal for any subsequent analysis and data archiving. To this aim, we developed an in-house cloud-computing system, named QSpike Tools, where CPU-intensive operations, required for preprocessing of each recorded channel (e.g., filtering, multi-unit activity detection, spike-sorting, etc.), are decomposed and batch-queued to a multi-core architecture or to a computers cluster. With the commercial availability of new and inexpensive high-density MEAs, we believe that disseminating QSpike Tools might facilitate its wide adoption and customization, and inspire the creation of community-supported cloud-computing facilities for MEAs users
Transcriptome Remodeling in Response to Leaf Removal and Exogenous Abscisic Acid in Berries of Grapevine (Vitis vinifera L.) Fruit Cuttings
Climate change is known to simultaneously increase berry sugars but decrease anthocyanins, leading to an imbalance between sugars and anthocyanins in grape berries. To restore the balance of sugars and anthocyanins, carbon limitation by leaf removal and exogenous abscisic acid (ABA) were separately or simultaneously applied to Vitis vinifera cv. Cabernet Sauvignon fruit cuttings to decipher their effects on berry quality with metabolite and whole-genome transcriptome analyses. Carbon limitation decreased the hexose concentration and fully blocked the accumulation of anthocyanins. However, exogenous ABA increased the anthocyanin concentration under both carbon limitation and sufficient conditions. Carbon limitation and exogenous ABA induced the profound remodeling of the whole-genome transcriptome and altered the anthocyanin concentration by regulating the transcription levels of genes involved in the anthocyanin biosynthesis pathways as well as in the genes involved in various types of hormone signaling. Moreover, two pertinent candidate genes were identified based on the co-expression network analysis between the berry metabolite and transcriptome results, including a transcriptional factor, ERF2, and a calcineurin B-like proteininteracting protein kinase gene, CIPK25. In summary, simultaneously modifying the carbon supply by leaf removal and spraying exogenous ABA could re-establish the balance between sugars and anthocyanins to improve the qualities of grape berries via whole-genome transcriptome remodeling
A Fast and Reliable Method for Simultaneous Waveform, Amplitude and Latency Estimation of Single-Trial EEG/MEG Data
The amplitude and latency of single-trial EEG/MEG signals may provide valuable information concerning human brain functioning. In this article we propose a new method to reliably estimate single-trial amplitude and latency of EEG/MEG signals. The advantages of the method are fourfold. First, no a-priori specified template function is required. Second, the method allows for multiple signals that may vary independently in amplitude and/or latency. Third, the method is less sensitive to noise as it models data with a parsimonious set of basis functions. Finally, the method is very fast since it is based on an iterative linear least squares algorithm. A simulation study shows that the method yields reliable estimates under different levels of latency variation and signal-to-noise ratioĂs. Furthermore, it shows that the existence of multiple signals can be correctly determined. An application to empirical data from a choice reaction time study indicates that the method describes these data accurately
Analytical methods and experimental approaches for electrophysiological studies of brain oscillations
Brain oscillations are increasingly the subject of electrophysiological studies probing their role in the functioning and dysfunction of the human brain. In recent years this research area has seen rapid and significant changes in the experimental approaches and analysis methods. This article reviews these developments and provides a structured overview of experimental approaches, spectral analysis techniques and methods to establish relationships between brain oscillations and behaviour
Exploring the Potential of Laser Capture Microdissection Technology in Integrated Oral BioSciences
Laser capture microdissection (LCM) is a high end research and diagnostic technology that helps in obtaining pure cell populations for the purpose of cell or lesion specific genomic and proteomic analysis. Literature search on the application of LCM in oral tissues was made through PUBMED. There is ample evidence to substantiate the utility of LCM in understanding the underlying molecular mechanism involving an array of oral physiological and pathological processes, including odontogenesis, taste perception, eruptive tooth movement, oral microbes, and cancers of the mouth and jaw tumors. This review is aimed at exploring the potential application of LCM in oral tissues as a high-throughput tool for integrated oral sciences. The indispensable application of LCM in the construction of lesion specific genomic libraries with emphasis on some of the novel molecular markers thus discovered is also highlighted. This article is protected by copyright. All rights reserved
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