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51.
I Ishaaya Y Birk A Bondi Y Tencer 《Journal of the science of food and agriculture》1969,20(7):433-436
The effect of soyabean saponins on the growth of chicks, mice, rats and Tribolium castaneum larvae and on the survival time of tadpoles and guppies was studied. Soyabean saponins did not impair growth of chicks when added at five times the concentration in a normal soyabean-supplemented diet. They had also no effect on the growth response of rats and mice and on the amount of ingested food, but caused slight growth retardation of Tribolium castaneum larvae. Soyabean saponins showed a pronounced detrimental effect on tadpoles and guppies. 相似文献
52.
PICASSO (PICture Aided Sophisticated Sketch Of database queries) is a graphics-based database query language designed for use with a universal relation database system. The primary objective of PICASSO is ease of use. Graphics are used to provide a simple method of expressing queries and to provide visual feedback to the user about the system's interpretation of the query. Inexperienced users can use the graphical feedback to aid them in formulating queries whereas experienced users can ignore the feedback. Inexperienced users can pose queries without knowing the details of underlying database schema and without learning the formal syntax of SQL-like query language. This paper presents the syntax of PICASSO queries and compares PICASSO queries with similar queries in standard relational query languages. Comparisons are also made with System/U, a non-graphical universal relation system on which PICASSO is based. The hypergraph semantics of the universal relation are used as the foundation for PICASSO and their integration with a graphical workstation enhances the usability of database systems. 相似文献
53.
Beate Pscheidt Zhibin Liu Richard Gaisberger Manuela Avi Wolfgang Skranc Karl Gruber Herfried Griengl Anton Glieder 《Advanced Synthesis \u0026amp; Catalysis》2008,350(13):1943-1948
Screening for stereoselective cyanohydrin synthesis in 96‐well plates was employed in the development of an efficient, pH‐stable hydroxynitrile lyase for the conversion of sterically hindered aliphatic aldehydes. Site‐saturation mutagenesis (SSM) resulted in a powerful catalyst for the stereoselective conversion of hydroxypivalaldehyde and pivalaldehyde to their corresponding (R)‐cyanohydrins (ee >97%) which are used as chiral building blocks (e.g., for pantothenic acid production). Furthermore, redesigning the PaHNL5 gene and improving its expression by Pichia pastoris with the help of a new PAOX1 promoter variant and the helper protein PDI (protein disulfide isomerase) led to elevated amounts of today’s most efficient biocatalyst for vitamin B5 synthesis. 相似文献
54.
Most mobile radio networks have been planned based on the classical cellular concept. However, alternative planning strategies
that lead to more efficient network configurations are necessary due to the fact that the traffic density is generally far
from constant throughout the service area, making necessary the relocation of base stations inside the traffic hotspots. If
the traffic is characterized in a discrete way, the optimization of base stations location resembles vector quantization,
a well-known problem in signal processing. In this paper, we use this analogy to propose a mobile radio network planning algorithm.
Simulation results show that higher trunking efficiency as well as improved frequency assignment can be obtained if an existing
mobile radio network is redesigned using the presented strategy.
Raúl Chávez-Santiago was born in Oaxaca City, Mexico. He obtained the B.Sc. degree in communications and electronics engineering in 1997 from
the School of Mechanical and Electrical Engineering (ESIME-IPN), and the M.Sc. degree in electrical engineering in 2001 from
the Center of Research and Advanced Studies of the National Polytechnic Institute (CINVESTAV-IPN) in Mexico City.
He has professional experience as Computer Networking Engineer, and Research and Teaching Assistant. Currently, he is completing
his studies toward the Ph.D. degree at Ben-Gurion University (BGU) of the Negev, Israel. In 2002, he received the URSI Young
Scientist Award. His main research interests are the optimal planning of radio communication networks, the electromagnetic
compatibility of terrestrial and satellite radio systems, and the efficient use of the radio spectrum. He is an IEEE and IEICE
student member, and a URSI radio scientist.
Avi Raymond was born in Yavne, Israel. He received the B.Sc. and M.Sc. degrees in electrical engineering from Ben-Gurion University (BGU)
of the Negev in 2000 and 2005, respectively.
He worked for two years in a communication company in the field of Telephony and Broadband Services. He also worked as a Research
Assistant in the communications laboratory at BGU. He currently works at Elta Electronic Industries Ltd. as System Engineer
and pursues studies toward a second M.Sc. degree in systems engineering at the Technion Institute of Technology, Haifa, Israel.
His research interests are the optimization algorithms for frequency assignment in cellular networks.
Vladimir Lyandres was born in 1944, in Vologda, Russia. He received the M.Sc. degree in communications engineering in 1966 and the Ph.D. degree
in communications theory in 1972 from the State University of Telecommunications (SUT), Saint Petersburg, Russia. He was with
SUT until 1990 holding a position of Senior Scientific Associate and working on research and development of digital transmission
systems, modeling of radio communication channels and algorithms of frequency planning for broadcasting and cellular systems.
Since 1991 he holds a position of Researcher at the communications laboratory and Professor at the Department of Electrical
and Computer Engineering, Ben-Gurion University (BGU) of the Negev, Israel. His research interests include synthesis of Markov
models, combinatorial optimization, and adaptive power loading. He is a senior member of IEEE and member of IEICE. 相似文献
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Cover Picture: Stabilization of Telomeric I‐Motif Structures by (2′S)‐2′‐Deoxy‐2′‐C‐Methylcytidine Residues (ChemBioChem 12/2017) 下载免费PDF全文
60.
Stabilization of Telomeric I‐Motif Structures by (2′S)‐2′‐Deoxy‐2′‐C‐Methylcytidine Residues 下载免费PDF全文
Dr. Anna Aviñó María Dellafiore Dr. Raimundo Gargallo Prof. Dr. Carlos González Dr. Adolfo M. Iribarren Dr. Javier Montserrat Prof. Dr. Ramon Eritja 《Chembiochem : a European journal of chemical biology》2017,18(12):1123-1128
G‐quadruplexes and i‐motifs are tetraplex structures present in telomeres and the promoter regions of oncogenes. The possibility of producing nanodevices with pH‐sensitive functions has triggered interest in modified oligonucleotides with improved structural properties. We synthesized C‐rich oligonucleotides carrying conformationally restricted (2′S)‐2′‐deoxy‐2′‐C‐methyl‐cytidine units. The effect of this modified nucleoside on the stability of intramolecular i‐motifs from the vertebrate telomere was investigated by UV, CD, and NMR spectroscopy. The replacement of selected positions of the C‐core with C‐modified residues induced the formation of stable intercalated tetraplexes at near‐neutral pH. This study demonstrates the possibility of enhancing the stability of the i‐motif by chemical modification. 相似文献