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991.
Francisco Cabrera-Chávez Josafat Marina Ezquerra-Brauer Ronaldo Herrera-Urbina Cristina M. Rosell 《International Journal of Food Properties》2013,16(6):1187-1198
The effect of semi-purified trypsin on the physicochemical properties of durum and bread wheat flour and gluten protein fractions was evaluated. Trypsin was partially isolated from sierra (Scomberomorus sierra) guts extracts by affinity chromatography. Treatment with enzyme caused hydrolysis of 1.16–1.40% in both durum and bread wheat gluten and gluten fractions. The effect of hydrolysis on the isoelectric point was more evident in durum that bread wheat gluten. Addition of the trypsin-like enzyme at three different concentrations induced a decrease in the gluten index. The dough consistency fell after 1.5 h of incubation. It was possible to modify wheat flour proteins by varying S. sierra trypsin-like enzyme concentration and incubation time, depending on the wheat species. 相似文献
992.
Ruth Klendauer Marina Berkovich Richard Gelvin Jan Marco Leimeister Helmut Krcmar 《Information Systems Journal》2012,22(6):475-503
Requirements engineering is a software development discipline, executed by requirements analysts (RAs), that includes requirements elicitation, analysis, specification and validation. Its successful outcome is very often essential to overall project success. However, there is a lack of systematically conducted empirical research on the competencies of RAs. This paper addressed this gap by conducting 64 interviews at eight major North American and European financial services companies. Our qualitative research design follows an interpretive approach and uses critical incident technique. We develop a competency model, which specifies 16 critical competencies, and integrates contextual and situational factors as well as results variables. ‘Consulting others’, ‘Testing assumptions and investigating’ and ‘Explaining concepts and opinions’ were the most frequently identified competencies. This indicates that for an effective analyst, close interaction and communication with customers is indeed crucial – but of equally importance is the critical questioning of the expressed needs. Surprisingly, applying specific tools and advanced techniques did not seem to play a significant role from the interviewees' perspective. This study contributes to theory as it is the first to elaborate a competency model for RAs. It also provides a foundation for the development of competency‐based training in companies and universities. 相似文献
993.
Wilfrido Torres‐Arreola Josafat Marina Ezquerra‐Brauer Ramón Pacheco‐Aguilar Elisa M. Valenzuela‐Soto Ofelia Rouzaud‐Sandez Maria E. Lugo‐Sanchez Gisela Carvallo‐Ruiz 《International Journal of Food Science & Technology》2012,47(5):947-953
Lysyl oxidase (LOX; E.C.1.4.3.13) was purified from jumbo squid muscle (Dosidicus gigas) with 1900‐fold and yield 1.9%, and characterized for the first time. The purification procedure consisted of fractionation with urea and a combination of size‐exclusion and anion‐exchange chromatography. The enzyme had a molecular weight of 32 kDa, as estimated by SDS‐PAGE. Using a specific LOX substrate (1,5‐diaminopentane), its optimum activity was determined at pH 8.2 and 65 °C. Activation energy (Ea) of the enzyme was 69.94 kJ K?1 mol?1. The enzyme was strongly inhibited by β‐aminopropionitrile fumarate (BAPN), a specific LOX inhibitor. Moreover, purified LOX was able to work at different temperatures (20–90 °C) at pH 8.2. Although further research is needed, the results from this work suggest that based on LOX activity, this enzyme may be of practical use in preventing textural changes in jumbo squid during storage or processing. 相似文献
994.
995.
Stefan Höfle Hung Do Eric Mankel Marina Pfaff Zhenhao Zhang Daniel Bahro Thomas Mayer Wolfram Jaegermann Dagmar Gerthsen Claus Feldmann Uli Lemmer Alexander Colsmann 《Organic Electronics》2013,14(7):1820-1824
In this work we present solution processed organic light emitting diodes (OLEDs) comprising small molecule, blue phosphorescent emitter layers from bis(4,6-difluorophenylpyridinato-N,C2)picolinatoiridium doped 4,4′,4″-tris(carbazol-9-yl)-triphenylamine and molybdenum trioxide (MoO3) anode buffer layers. The latter were applied from a molybdenium(V)ethoxide precursor solution that was thermally converted to MoO3 at moderate temperatures. The high work function MoO3 facilitated hole injection into the emission layer. The MoO3 layer properties were investigated by means of energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, ultraviolet photoelectron spectroscopy and Kelvin probe force microscopy. MoO3 buffer layers performed superior to the commonly used poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) and enabled an enhanced OLED device efficiency. 相似文献
996.
Mauro De Sanctis Simone Quaglieri Ernestina Cianca Marina Ruggieri 《Wireless Personal Communications》2005,34(1-2):189-209
This paper addresses the issue of energy efficiency for error control mechanisms over WPAN systems. An analytical formulation
has been developed to study the trade-off between link layer performance and energy consumption for two types of error control
schemes: pure ARQ and type II hybrid ARQ protocol. An MC-CDMA-based system is considered. First of all, the analysis has been
used to compare different error recovery schemes from the energy efficiency point of view. Moreover, it has been found that,
for any channel conditions, there exists an optimal value of the transmit power that maximizes the energy efficiency. The
paper also shows how this result can be used to design the power control of an energy efficient CDMA-based communication system.
Mauro De Sanctis received the “Laurea' degree in Telecommunications Engineering from the University of Roma “Tor Vergata' in 2002. He is
currently a Ph.D. Student and Assistant Professor in the Department of Electronics Engineering of the same University. He
is involved in the DAVID (DAta and Video Interactive Distribution) satellite mission of the ASI (Italian Space Agency); his
research is funded by the ASI. He is also involved in the MAGNET (My personal Adaptive Global NET) European FP6 integrated
project and in the SatNEx European network of excellence. He worked on Italian national research projects on satellite-terrestrial
systems integration such as SHINES (Satellite and HAP Integrated NEtworks and Services) and CABIS (CDMA for Broadband mobile
terrestrial-satellite Integrated Systems). On autumn 2004 he joined the CTIF (Center for TeleInFrastructure), a research center
focusing on modern telecommunications technologies located at the University of Aalborg (Denmark). His main areas of interest
are: integration of different satellite networks, stratospheric platforms and terrestrial networks in a multi-layered fashion,
internetworking and resource management in satellite systems and energy efficiency of WPAN systems.
Simone Quaglieri received the “Laurea' degree cum laude in Telecommunications Engineering from the University of Roma “Tor Vergata', Italy,
in 2004. His thesis, concerning the study of an analytic model for the Raman amplifier in optical systems with high bit rate,
has been developed in the same University. During 2002 he worked as stagiaire on the design and development of optical submarine
systems at the Elettra company (Telecom Italia group, Italy). He is joining the IRIS (Innovative Radio Integrated Systems)
group at the University of Roma “Tor Vergata' as Research Engineer, where he is working on MC-CDMA based technology in the
frame of the MAGNET (My Adaptive Global NETwork) European project. He is also working on error recovery mechanisms over satellite
systems, and his research is funded by the EC in the frame of the SatNEx (Satellite Network of Excellence) European project.
Ernestina Cianca graduated cum laude in Electronics Engineering in 1997 at the University of L'Aquila. She was with Italtel/Siemens (L'Aquila)
from 1997 to 1998. She got her Ph.D. degree from the University of Rome Tor Vergata (URTV). The thesis work was on power management
in CDMA-based satellite systems. She has been employed by the University of Aalborg, Denmark, in the Wireless Networking Groups
(WING), as Research engineer (2000–2001) and as Assistant Professor (2001–2003). In particular, from Sept. 2002 she has been
Technical Manager of Aalborg University for the IST-STRIKE project. She is currently Assistant Professor in Telecommunications
at the URTV (Dpt. of Electronics Engineering), teaching DSP, Information and Coding. Her research mainly concerns wireless
access technologies (CDMA and MIMO-OFDM-based systems), in particular, Radio Resource Management at PHY/MAC layer, ARQ/HARQ,
TCP-IP issues over wireless links, integration of terrestrial and satellite systems. She has been the vice-coordinator of
the following national research programs: CABIS, on CDMA integrated mobile systems (2000-2002) and SHINES, on satellite-HAP
integrated networks for multimedia applications co-financed by MIUR (2002–2004). She is currently working on various European
Projects: EU FP6 IP MAGNET (My personal Adaptive Global NET); EU ASIA LINK EAGER-NetWIC (Euro-Asian Network for Strengthening
Graduate Education and Research in Wireless Communications); EU Network of excellence NEXWAY. She is author of about 40 papers,
on international journals/transactions and proceedings of international conferences.
Marina Ruggieri graduated in Electronics Engineering in 1984 at the University of Roma. She was: with FACE-ITT and GTC-ITT (Roanoke, VA)
in the High Frequency Division (1985–1986); Research and Teaching Assistant at the University of Roma Tor Vergata (URTV) (1986–1991);
Associate Professor in Telecommunications at the University of L'Aquila (1991–1994). Since November 2000 she is Full Professor
in Telecommunications at the URTV (Dpt. of Electronics Engineering), teaching DSP, Information and Coding. In 1999 she has
been appointed member of the Board of Governors of the IEEE AES Society (2000–2002) and re-elected for the period 2003–2005.
Her research mainly concerns space communications and navigation systems (in particular satellites) as well as mobile and
multimedia networks. She is the Principal Investigator of: satellite scientific communications missions (DAVID, WAVE) of ASI;
national research programs (CABIS) on CDMA integrated mobile systems (2000–2002) and on satellite-HAP integrated networks
for multimedia applications (SHINES), co-financed by MIUR (2002–2004). She co-ordinates the URTV Unit in various European
Projects: EU FP6 IP MAGNET (My personal Adaptive Global NET); EU ASIA LINK EAGER-NetWIC (Euro-Asian Network for Strengthening
Graduate Education and Research in Wireless Communications); EU Network of excellence NEXWAY; GALILEO JU 1st Call – July 2003:
VERT (VEhicular Remote Tolling); and in the ASI program on V-band payloads (TRANSPONDERS). She is member of the Editorial
Board of Wireless Personal Communications – an International Journal (Kluwer). She was awarded the 1990 Piero Fanti International
Prize and she had a nomination for the Harry M. Mimmo Award in 1996 and the Cristoforo Colombo Award in 2002. She is author
of about 170 papers, on international journals/transactions and proceedings of international conferences, book chapters and
books. 相似文献
997.
Alexander N. Shikov Olga N. Pozharitskaya Marina N. Makarova H.J. Damien Dorman Valery G. Makarov Raimo Hiltunen Bertalan Galambosi 《Journal of Functional Foods》2010,2(1):71-76
The adaptogenic effect of Bergenia crassifolia black and fermented leaves was examined based on the forced swimming capacity and the change of biochemical parameters in mice. The treatment groups were orally administered infusions of black and fermented leaves of 3 populations of B. crassifolia, while the control group received distilled water for 7 days. Infusions from black leaves of B. crassifolia insignificantly enhanced the maximum swimming capacity of mice by increasing fat utilization, and by delaying the accumulation of plasma lactate while infusions from fermented leaves of B. crassifolia significantly enhanced the maximum swimming capacity of mice without change of the body weight by increasing glucose utilization and decreasing lactate level compared to the control group. 相似文献
998.
Laura Esposito Thierry Epicier Marina Serantoni Andreana Piancastelli Daniele Alderighi Angela Pirri Guido Toci Matteo Vannini Sergiu Anghel Georges Boulon 《Journal of the European Ceramic Society》2012,32(10):2273-2281
Transparent 9.8 at% Yb:YAG ceramic samples were prepared by reactive sintering of commercial oxides and using 0 or 1 wt% polyethylene glycol (PEG) as dispersant. The optical quality of the samples turns out to be improved by using a dispersant and optical transmittance close to the commercial samples has been obtained. On the other hand the laser characterization evidenced the activation of a non-linear loss mechanism occurring only in the sample containing PEG and despite its better optical quality, at high excitation level. A SEM analysis of material microstructure could not explain this behavior. A state of the art TEM analysis at nanometric scale was performed providing high resolution chemical spectroscopic results that indicate the presence of amorphous and crystalline silicate phases playing different roles in the two samples. 相似文献
999.
We use several different sources (a 1970 Roster of Organizations in Data Processing and the 1960 and 1970 Censuses of Population) to study patterns of geographic clustering at the very origins of the software industry. We find a strong trend toward clustering of the industry in a few metropolitan areas. Furthermore, we uncover a tendency in the early software industry to agglomerate in close proximity to some of its main customers. This tendency holds even after controlling for region-specific heterogeneity and for the potentially endogenous nature of the software customers' location decisions. We explore the factors that may have driven the observed clustering patterns and suggest directions for further research. 相似文献
1000.
Marina Czerner María I. Yeannes 《International Journal of Food Science & Technology》2010,45(10):2001-2007
Brining is a preliminary operation in the process of salting–ripening anchovy in which, conventionally, whole fish is immersed in saturated brine (osmotic solution) until equilibrium. The aim of this work was to study the mass transfer kinetics in three different cuts of anchovy (whole fish, gutted fish and fillet) and to model it using the Zugarramurdi and Lupín and the Peleg equations. Fillet reached equilibrium after 5 h, gutted fish after 10.42 h and whole fish after 19.75 h. Equilibrium constants were 1.054, 0.706 and 0.603 for fillet, gutted fish and whole anchovy, respectively. These results indicate that the presence of skin affects both the initial rate of mass transfer and the equilibrium water and salt content. The Peleg model was more suitable to describe the salt gain kinetics, and the Zugarramurdi and Lupín model results in a more accurate prediction of water loss and equilibrium conditions. 相似文献