32,193 research outputs found
High-Efficiency Gene Transfer into Adult Fish : a New Tool to Study Fin Regeneration
No full textZebrafish represents an excellent model to study the function of vertebrate genes (e.g., well-developed genetics, large number of mutants, and genomic sequencing in progress), inasmuch as we have tools to manipulate gene expression. Recent use of injected morpholinos in eggs provides a good method to " knockdown " gene expression in early development (Nasevicius and Ekker, 2000), and the "caged" RNA injected in eggs allows to overexpress a gene in a specific set of cells (Ando et al., 2001). However, a method to specifically modify gene expression in the juvenile or in the adult is still missing. Such a method would be a very powerful tool to understand gene function in differentiated tissues. We describe here an electroporation-based approach, which allows gene transfer in adult tissues. Its efficiency was assessed using a GFP (green fluorescent protein) dependent assay. We then used this method to disrupt the Fgf signalling pathway during the process of regeneration
Erratum: High-efficiency gene transfer into adult fish: A new tool to study fin regeneration (Genesis (January 2002) 32 (27-31))
No full textA simple multiband printed bowtie antenna
No full textThis letter presents a new approach for the design of a multiresonant printed bowtie antenna. Several techniques were attempted to obtain one antenna which is operational in the 2, 3, and 5 GHz bands corresponding to many wireless applications. The idea of creating different slot configurations on different parts of a single antenna is the basic principle. A prototype of the final antenna design was fabricated tested and a good agreement was found between simulated and tested results. © 2008 IEEE.Balanis C. A., 2005, ANTENNA THEORY ANAL; Birch M, 2002, P SOC PHOTO-OPT INS, V4758, P573, DOI 10.1117-12.462195; Eldek AA, 2005, IEEE T ANTENN PROPAG, V53, P3067, DOI 10.1109-TAP.2005.851870; James J.R., 1989, IEE ELECTROMAGNETIC, V28; Karacolak T, 2006, IEEE ANTENN WIREL PR, V5, P446, DOI 10.1109-LAWP.2006.885013; Kiminami K, 2004, IEEE ANTENN WIREL PR, V3, P152, DOI 10.1109-LAWP.2004.832126; Lin YD, 1998, IEEE T ANTENN PROPAG, V46, P459; Nedil M., 2003, P CAN C EL COMP ENG, V3, P1433; Nishioka Y, 1999, IEEE T ANTENN PROPAG, V47, P970, DOI 10.1109-8.777119; TAWK Y, 2007, THESIS AM U BEIRUT L; Uduwawala D, 2004, IEEE T GEOSCI REMOTE, V42, P732, DOI 10.1109-TGRS.2003.819442; Yazdandoost K. Y., 2005, P IEEE WIRELESS COMM, P21282
A low-cost microstrip antenna for 3G-WLAN-WiMAX and UWB applications
No full textThis paper presents a low-cost ultra-wideband microstrip antenna for wireless communications. Printed on a 40×50×1.83 mm3 Isola Gigaver 210 substrate, the antenna features a microstrip feed line with two 45° bends and a tapered section for size reduction and matching, respectively. The ground plane is partial and comprises a rectangular part and a trapezoidal part. The patch is a half ellipse, where the cut is made along the minor axis. Several slots are incorporated into the patch. The placement and sizes of the slots are assisted by the knowledge of fractal geometries . The return loss, input impedance, gain, efficiency and radiation characteristics of the antenna are presented. It is shown that the antenna can operate in the bands used for UMTS, WLAN, WiMAX, and UWB applications. © 2009 IEEE.*AG TECHN, ADS MOM 2006; Al-Husseini M., 2008, 2008 INT WIR COMM MO; ALHUSSEINI M, 2009, 26 NAT RAD SCI C NRS; Balanis C. A., 2005, ANTENNA THEORY ANAL; El-Khamy S. E., 2004, 21 NAT RAD SCI C NRS, P1; Kumar G., 2003, BROADBAND MICROSTRIP; Low ZN, 2005, IEEE ANTENN WIREL PR, V4, P237, DOI 10.1109-LAWP.2005.852577; Werner DH, 2003, IEEE ANTENN PROPAG M, V45, P38, DOI 10.1109-MAP.2003.1189650; Zhang JP, 2008, IEEE T ANTENN PROPAG, V56, P241, DOI 10.1109-TAP.2007.91316510
Landsat MSS classification of fire fuel types in Wood Buffalo National Park, northern Canada
No full textJ1: Global Ecology & Biogeography Letters; M3: Article; Milne, David Franklin, Steven E. Wilson, Bradley A. Ghitter, Geoff Heathcott, Mark McCaffrey, Thomas M. Ow, Charlotte F. Y.; Source Information: Mar1994, Vol. 4 Issue 2, p33; Subject Term: FOREST fires; Author-Supplied Keyword: Canada (Wood Buffalo National Park); Author-Supplied Keyword: Forest fire; Author-Supplied Keyword: Fuel type classification; Author-Supplied Keyword: Landsat data; Number of Pages: 0p; Document Type: Articl
The long-wavelength view of GG Tau A: rocks in the ring world
No full textWe present the first detection of GG Tau A at centimetre wavelengths, made with the Arcminute Microkelvin Imager Large Array at a frequency of 16 GHz (λ = 1.8 cm). The source is detected at >6 σrms with an integrated flux density of S16GHz = 249 ± 45 µJy. We use these new centimetre-wave data, in conjunction with additional measurements compiled from the literature, to investigate the long-wavelength tail of the dust emission from this unusual protoplanetary system. We use an MCMC-based method to determine maximum likelihood parameters for a simple parametric spectral model and consider the opacity and mass of the dust contributing to the microwave emission. We derive a dust mass of Md ~ 0.1 Msun, constrain the dimensions of the emitting region and find that the opacity index at λ > 7 mm is less than unity, implying a contribution to the dust population from grains exceeding ~4 cm in size. We suggest that this indicates coagulation within the GG Tau A system has proceeded to the point where dust grains have grown to the size of small rocks with dimensions of a few centimetres. Considering the relatively young age of the GG Tau association in combination with the low derived disc mass, we suggest that this system may provide a useful test case for rapid core accretion planet formation models
Letter from Cedrick M. Shimo to the Office of Redress Administration, June 4, 1991
No full textA letter from Cedrick M. Shimo to the Office of Redress Administration arguing that John Y. Udaka is entitled to a redress payment.These materials are from box 73 and 74 of the Frank Chin Papers. The Frank Chin Papers contain personal and professional correspondence between Frank Chin and Michi Weglyn relating to particular projects on which either author was working as well as files related to the Day of Remembrance Tribute to Michi Weglyn
THE STAPHYLOCOCCAL PANTON AND VALENTINE LEUKOCIDIN AND gamma-HAEMOLYSIN HLGC/HLGB SHARE C5AR AS A RECEPTOR, BUT OPERATE DIVERSE INTRACELLULAR ACTIVITIES IN HUMAN POLYMORPHONUCLEAR NEUTROPHILS
No full textLos jesuitas expulsos literatos en la Italia del Setecientos : éxitos y fracasos
No full textLa historiografía ha definido a los jesuitas españoles expulsos como "mediatores" entre dos culturas: durante el largo exilio italiano (1767-1815) ellos, gracias a la habilidad sincrética propia de la Compañía de Jesús, llegaron a producir una "cultura hispano italiana", según la célebre definición de M. Batllori. El propósito de mi intervención es ofrecer unas breves reflexiones sobre unas figuras de ex-jesuitas epañoles "literatos", particularmente Juan Andrés y Esteban Arteaga. Aunque varios expulsos alcanzaron un buen éxito literario, la mayoría de ellos experimentó los sinsabores, las miserias y las dificultades económicas propias del amplio sector de la intelectualidad que intentó emerger en el difícil escenario de la República literaria europea del siglo XVIII, un sector que el gran especialista en la Ilustración francesa Robert Darnton ha definido como Grub street.Expelled Spanish jesuits have been regarded by current Historiography as "cultural mediators": during their long exile in Italy (1767-1815), they developed a "Spanish Italian culture" (according to M. Batllori's definition) thanks to a meaningful syncretic approach. The author offers some brief reflections on those expelled jesuits who decided to porsue a litterary career, with a specific focus on Juan Andrés and Esteban Arteaga. Through several spanish fathers achieved a good literary success, the majority of them suffered the typical failures, delusions and troubles experienced by eighteenth century men of letters, especially those who belonged to a sector of the Republic of Letters called by Robert Darnton "Grub Street"
Nonstrangulating small colon obstruction caused by a submucosal haematoma
No full textS. Stahel, C. B. Riley, M. Wichtel and P.-Y. Daous
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