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https://www.readbyqxmd.com/read/28214134/intensification-of-heterogeneously-catalyzed-suzuki-miyaura-cross-coupling-reaction-using-ultrasound-understanding-effect-of-operating-parameters
#1
Sonam V Sancheti, Parag R Gogate
Palladium-catalyzed Suzuki-Miyaura cross-coupling reaction is a significant reaction for obtaining industrially important products. The current research work deals with intensification of reaction of 4-bromoanisole and phenylboronic acid catalyzed with 5wt% Pd/C (5% by weight Pd supported on C available as commercial catalyst) using ultrasound and more importantly, without use of any additional phase transfer catalyst. Heterogeneous catalyst has been selected in the present work so as to harness the benefits of easy separation and the possible limitations of heterogeneous operation are minimized by introducing ultrasonic irradiations...
January 27, 2017: Ultrasonics Sonochemistry
https://www.readbyqxmd.com/read/28213194/subcortical-mapping-using-an-electrified-cusa-in-pediatric-supratentorial-surgery
#2
Jonathan Roth, Akiva Korn, Yifat Bitan-Talmor, Rivka Kaufman, Margaret Ekstein, Shlomi Constantini
BACKGROUND: Intraoperative electrophysiology is increasingly used for various lesion resections, both in adult and pediatric brain surgery. Subcortical mapping is often used in adult surgery when lesions lie in proximity to the corticospinal tract (CST). We describe a novel technique of continuous subcortical mapping using an electrified Cavitron UltraSonic Aspirator (CUSA) in children with supratentorial lesions. METHODS: We evaluated the method of subcortical mapping using a CUSA as a stimulation probe...
February 14, 2017: World Neurosurgery
https://www.readbyqxmd.com/read/28213146/linear-ultrasonic-motor-for-absolute-gravimeter
#3
Yue Jian, Zhiyuan Yao, Vadim V Silberschmidt
Thanks to their compactness and suitability for vacuum applications, linear ultrasonic motors are considered as substitutes for classical electromagnetic motors as driving elements in absolute gravimeters. Still, their application is prevented by relatively low power output. To overcome this limitation and provide better stability, a V-type linear ultrasonic motor with a new clamping method is proposed for a gravimeter. In this paper, a mechanical model of stators with flexible clamping components is suggested, according to a design criterion for clamps of linear ultrasonic motors...
February 1, 2017: Ultrasonics
https://www.readbyqxmd.com/read/28212947/affective-valence-of-neurons-in-the-vicinity-of-the-rat-amygdala-single-unit-activity-in-response-to-a-conditioned-behavior-and-vocal-sound-playback
#4
Hiroko Kagawa, Yoshimasa Seki, Kazuo Okanoya
We recorded single unit activity within and around the rat amygdala while rats were engaged in an operant task (which included both reward and aversive trials) and during playback of ultrasonic vocalizations (USVs) to determine if there existed neurons which responded to two different types of either positive contexts (i.e., water reward and positively associated 50kHz vocalizations) or negative contexts (i.e., white noise and negatively associated 22kHz vocalizations). Ultimately, we wanted to determine if these two contexts (operant condition task and vocal sounds) could be represented as either positive or negative in a single neuron...
February 14, 2017: Behavioural Brain Research
https://www.readbyqxmd.com/read/28212513/simultaneous-removal-of-no-and-hg-0-over-ce-cu-modified-v2o5-tio2-based-commercial-scr-catalysts
#5
Guilong Chi, Boxiong Shen, Ranran Yu, Chuan He, Xiao Zhang
A series of novel Ce-Cu modified V2O5/TiO2 based commercial SCR catalysts were prepared via ultrasonic-assisted impregnation method for simultaneous removal of NO and elemental mercury (Hg(0)). Nitrogen adsorption, X-ray diffraction (XRD), temperature programmed reduction of H2 (H2-TPR) and X-ray photoelectron spectroscopy (XPS) were used to characterize the catalysts. 7% Ce-1% Cu/SCR catalyst exhibited the highest NO conversion efficiency (>97%) at 200-400°C, as well as the best Hg(0) oxidation activity (>75%) at 150-350°C among all the catalysts...
February 12, 2017: Journal of Hazardous Materials
https://www.readbyqxmd.com/read/28212081/a-comparative-analysis-of-cmut-receiving-architectures-for-design-optimization-of-integrated-transceiver-front-ends
#6
Marco Sautto, Alessandro Stuart Savoia, Fabio Quaglia, Giosue Caliano, Andrea Mazzanti
A formal comparison between fundamental RX amplifier configurations for Capacitive Micromachined Ultrasonic Transducers (CMUT) is proposed in this paper. The impact on both RX and the pulse-echo frequency response and on the output SNR are thoroughly analysed and discussed. It is shown that the resistive-feedback amplifier yields a band-pass RX frequency response, while both open-loop voltage and capacitivefeedback amplifiers exhibit a low-pass frequency response. For a given power dissipation, it is formally proved that a capacitivefeedback amplifier provides a remarkable SNR improvement against the commonly adopted resistive feedback stage, achieved at the expense of a reduced pulse-echo center frequency, making its use convenient in low and mid-frequency ultrasound imaging applications...
February 13, 2017: IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
https://www.readbyqxmd.com/read/28211510/broadband-gradient-impedance-matching-using-an-acoustic-metamaterial-for-ultrasonic-transducers
#7
Zheng Li, Dan-Qing Yang, Shi-Lei Liu, Si-Yuan Yu, Ming-Hui Lu, Jie Zhu, Shan-Tao Zhang, Ming-Wei Zhu, Xia-Sheng Guo, Hao-Dong Wu, Xin-Long Wang, Yan-Feng Chen
High-quality broadband ultrasound transducers yield superior imaging performance in biomedical ultrasonography. However, proper design to perfectly bridge the energy between the active piezoelectric material and the target medium over the operating spectrum is still lacking. Here, we demonstrate a new anisotropic cone-structured acoustic metamaterial matching layer that acts as an inhomogeneous material with gradient acoustic impedance along the ultrasound propagation direction. When sandwiched between the piezoelectric material unit and the target medium, the acoustic metamaterial matching layer provides a broadband window to support extraordinary transmission of ultrasound over a wide frequency range...
February 17, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28209004/comparison-of-sealer-penetration-by-using-different-irrigation-techniques-an-in-vitro-study
#8
Prabu Mahin Syed Ismail, Siddiq Ahamed, P B Sabiha, M Chandra Sekhar, Gopikrishna Moosani, S Nagalakshmi Reddy, N Upendranatha Reddy, C H Sumanthi
INTRODUCTION: The main goal of root canal treatment is to eliminate the microorganisms particularly in the apical third area and to prevent re-infection. In order to achieve these goals the instrumentation must be combined with adequate irrigation. AIM: To compare sealer penetration by using different irrigation techniques i.e., apical negative pressure irrigation, Passive Ultrasonic Irrigation (PUI) and combination of apical negative pressure irrigation and PUI...
December 2016: Journal of Clinical and Diagnostic Research: JCDR
https://www.readbyqxmd.com/read/28207553/laparoscopic-living-donor-right-hemihepatectomy-with-venous-outflow-reconstruction-using-cadaveric-common-iliac-artery-allograft-case-report-and-literature-review
#9
Jiaxin Li, Jiwei Huang, Hong Wu, Yong Zeng
RATIONALE: With the development of laparoscopic technique, the total laparoscopic living donor right hemihepatectomy (LLDRH) procurement surgery has been successfully performed in many liver transplant centers all over the world, and the number of cases is continuing to increase. We report our case of laparoscopic right graft resection with venous outflow reconstruction using cadaveric common iliac artery allograft in our center and review literatures about total LLDRH surgery. PATIENT CONCERNS AND DIAGNOSES: A 40-year-old male living donor for right hepatectomy was selected after pretransplant evaluation including laboratory tests, liver volume, anatomy of hepatic vein, artery, portal vein, and bile duct...
February 2017: Medicine (Baltimore)
https://www.readbyqxmd.com/read/28204507/foxp1-expression-is-essential-for-sex-specific-murine-neonatal-ultrasonic-vocalization
#10
Henning Fröhlich, Rafiullah Rafiullah, Nathalie Schmitt, Sonja Abele, Gudrun A Rappold
No abstract text is available yet for this article.
February 15, 2017: Human Molecular Genetics
https://www.readbyqxmd.com/read/28203008/-effects-of-different-techniques-on-removal-of-vapor-lock-in-the-apical-region-of-curved-canals-a-cone-beam-computed-tomography-study
#11
Z Su, Y H Bai, X M Hou
OBJECTIVE: To compare the effect of four different techniques on removal of vapor lock in the apical region of curved root canals. METHODS: Forty simulated resin root canals with 45° curvature were prepared using WaveOne Primary, then the apical foramen were sealed with soft wax. The teeth were divided randomly into 4 groups thereafter (n=10). Contract solution was injected into the canals using a 30 G side-vented needle and scanned with cone-beam CT (CBCT) to identify the volume of the vapor lock...
February 18, 2017: Beijing da Xue Xue Bao. Yi Xue Ban, Journal of Peking University. Health Sciences
https://www.readbyqxmd.com/read/28197554/does-size-really-matter-the-role-of-tonotopic-map-area-dynamics-for-sound-learning-in-mouse-auditory-cortex
#12
Hans Sperup Brünner, Rune Rasmussen
This commentary centers on the novel findings by Shepard et al. (2016) published in eNeuro. The authors interrogated tonotopic map dynamics in auditory cortex (ACtx) by employing a natural sound-learning paradigm, where mothers learn the importance of pup ultrasonic vocalizations (USVs), allowing Shepard et al. to probe the role of map area expansion for auditory learning. They demonstrate that auditory learning in this paradigm does not rely on map expansion but is facilitated by increased inhibition of neurons tuned to low-frequency sounds...
January 2017: ENeuro
https://www.readbyqxmd.com/read/28195362/low-intensity-ultrasound-enhances-histone-acetylation-and-inhibition-of-interleukin-6-messenger-rna-expression-by-the-histone-deacetylase-inhibitor-sodium-butyrate-in-fibroblasts
#13
Noriaki Maeshige, Yuka Koga, Masayuki Tanaka, Michiko Aoyama-Ishikawa, Makoto Miyoshi, Makoto Usami, Hidemi Fujino
OBJECTIVES: Sodium butyrate, an inhibitor of histone deacetylase, has several therapeutic actions, including anti-inflammation. These actions depend on the concentration of sodium butyrate. In addition, lower concentrations have shown no effect on inflammation. Sonoporation by ultrasound can modify the permeability of the cell plasma membrane. Thus, the effects of sodium butyrate may be enhanced by the ultrasonic acoustics. Therefore, the facilitative effects of low-intensity ultrasound on histone acetylation and interleukin 6 (IL-6) regulation by sodium butyrate were investigated in this study...
February 3, 2017: Journal of Ultrasound in Medicine: Official Journal of the American Institute of Ultrasound in Medicine
https://www.readbyqxmd.com/read/28195290/microbubbles-trigger-oscillation-of-crystal-size-in-solids
#14
Anna Kollath, Nadzeya Brezhneva, Ekaterina V Skorb, Daria V Andreeva
An understanding of the nature and conditions of nonlinear processes in open systems is important for modulation of the microstructure of solids at a new level of complexity. We demonstrate that cavitation generated by high intensity ultrasound (HIUS) triggers nonlinear processes in microparticles and layers of titanium. We reveal a non-monotonic dependence of the size of grains in the treated solids on sonication time, and oscillation of titanium grain sizes vs. time of ultrasonic treatment, indicating the influence of two opposing forces: cavitation driven impact of shock heating and shear stress on surfaces...
February 14, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28194408/ciprofloxacin-controlled-solid-lipid-nanoparticles-characterization-in-vitro-release-and-antibacterial-activity-assessment
#15
Gamal A Shazly
The objective of this research was to formulate ciprofloxacin (CIP) in solid lipid nanoparticles (SLNs) in an attempt to develop a controlled drug delivery system. An ultrasonic melt-emulsification method was used for preparing CIP-loaded SLNs. Key findings included that SLNs were successfully produced with average particle sizes ranging from 165 to 320 nm and polydispersity index in the range of 0.18-0.33. High entrapment efficiency values were reported in all formulations. The atomic force scanning microscopic images showed spherical shape with the size range closer to those found by the particle size analyzer...
2017: BioMed Research International
https://www.readbyqxmd.com/read/28192905/extracting-metallic-nanoparticles-from-soils-for-quantitative-analysis-method-development-using-engineered-silver-nanoparticles-and-sp-icp-ms
#16
D M Schwertfeger, Jessica R Velicogna, Alexander H Jesmer, Selin Saatcioglu, Heather McShane, Richard P Scroggins, Juliska I Princz
The lack of an efficient and standardized method to disperse soil particles and quantitatively subsample the nanoparticulate fraction for characterization analyses is hindering progress in assessing the fate and toxicity of metallic engineered nanomaterials in the soil environment. This study investigates various soil extraction and extract preparation techniques for their ability to remove nanoparticulate Ag from a field soil amended with biosolids contaminated with engineered silver nanoparticles (AgNPs), while presenting a suitable suspension for quantitative single-particle inductively coupled plasma mass spectroscopy (SP-ICP-MS) analysis...
January 30, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28190055/optical-trap-loading-of-dielectric-microparticles-in-air
#17
Haesung Park, Thomas W LeBrun
We demonstrate a method to trap a selected dielectric microparticle in air using radiation pressure from a single-beam gradient optical trap. Randomly scattered dielectric microparticles adhered to a glass substrate are momentarily detached using ultrasonic vibrations generated by a piezoelectric transducer (PZT). Then, the optical beam focused on a selected particle lifts it up to the optical trap while the vibrationally excited microparticles fall back to the substrate. A particle may be trapped at the nominal focus of the trapping beam or at a position above the focus (referred to here as the levitation position) where gravity provides the restoring force...
February 5, 2017: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/28189855/in-vitro-and-ex-vivo-delivery-of-tailored-sirna-nanoliposomes-for-e2f1-silencing-as-a-potential-therapy-for-colorectal-cancer
#18
Sabrina Bochicchio, Barbara Dapas, Ilaria Russo, Carolina Ciacci, Ornella Piazza, Stefaan De Smedt, Eline Pottie, Anna Angela Barba, Gabriele Grassi
Tailored developed nanoliposomes loaded with a siRNA against the transcription factor E2F1 (siE2F1), were produced and delivered to human colorectal adenocarcinoma cell lines and to intestinal human biopsies. siE2F1 loaded nanoliposomes were produced through a dedicated ultrasound assisted technique producing particles with about 40nm size (Small Unilamellar Vesicles, SUVs) and 100% siRNA encapsulation efficiency. Compared to other production methods, the one proposed here can easily produce particles in the nanometric scale by suitable ultrasonic duty cycle treatments...
February 8, 2017: International Journal of Pharmaceutics
https://www.readbyqxmd.com/read/28189103/ultrasound-assisted-dispersive-liquid-liquid-microextraction-for-the-determination-of-seven-recreational-drugs-in-human-whole-blood-using-gas-chromatography-mass-spectrometry
#19
Zebin Lin, Jiaolun Li, Xinyu Zhang, Meihong Qiu, Zhibin Huang, Yulan Rao
Recreational drugs have large impact on public health and security, and to monitor them is of urgent demand. In the present study, ultrasound-assisted dispersive liquid-liquid microextraction combined with the detection of gas chromatography-mass spectrometry was applied to the determination of seven common recreational drugs, including amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine, 3,4-methylenedioxymethamphetamine, meperidine, methadone and ketamine in 200μL of human whole blood. A series of factors which would affect the extraction efficiency were systematically investigated, including the nature and the volume of extraction and dispersing solvents, ultrasonication time, salting-out effect and pH value...
January 22, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/28188348/graphene-oxide-fe3o4-as-sorbent-for-magnetic-solid-phase-extraction-coupled-with-liquid-chromatography-to-determine-2-4-6-trinitrotoluene-in-water-samples
#20
Luciana Costa Dos Reis, Lorena Vidal, Antonio Canals
A fast, simple, economical, and environmentally friendly magnetic solid-phase extraction (MSPE) procedure has been developed to preconcentrate 2,4,6-trinitrotoluene (TNT) from water samples prior to determination by liquid chromatography-UV-Vis employing graphene oxide/Fe3O4 nanocomposite as sorbent. The nanocomposite synthesis was investigated, and the MSPE was optimized by a multivariate approach. The optimum MSPE conditions were 40 mg of nanocomposite, 10 min of vortex extraction, 1 mL of acetonitrile as eluent, and 6 min of desorption in an ultrasonic bath...
February 10, 2017: Analytical and Bioanalytical Chemistry
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