A study of the perceptions of elementary school principals from one school division regarding the skills and knowledge of computer technology critical to their job performance

The purpose of this study was to determine what elementary principals perceive as important to performing their jobs in three areas: understanding student learning as it relates to computer technology use, decision making related to computer technology implementation and personal computer applications. Descriptive research methodology was used in the study. The population surveyed included 147 elementary principals in a large suburban school district located in the Washington, D.C. metropolitan area. Their schools were diverse in terms of size, demographics, and computer technology capabilities. One hundred twenty-seven surveys were returned, representing a response rate of 86%. The principals who responded registered the highest measure of agreement on the statements that addressed computer applications and student learning. There was less agreement regarding whom principals rely on when making decisions on computer technology implementation. However, respondents all agreed that they should know which key personnel to contact when making decisions particularly about the purchase of hardware and software. There was also solid agreement among the respondents that there should be a designated technology position in every school. The role of principal as it relates to computer technology implementation was not clearly defined by the respondents. Some principals felt it was important to model computer technology applications while others did not think that the principal was the most important person to facilitate an environment that supports technology. Finally, the area that received the most discrepancy in responses addressed personal productivity. There is not agreement among elementary principals as to what they should know and use regarding computer applications. All respondents, however, said that they were willing to participate in staff development designed to enhance their administrative roles.Ed. D

Some constraints assuring serializability in multidatabases

AbstractIn a multidatabase system, global transactions are executed under the control of the global system, while local transactions are submitted to each local system being outside of the global control. Since the multidatabase system is not aware of the local transactions and the conflicts they may cause, it has difficulty in detecting such conflicts. In [1], the authors gave the following constraints: global transactions should be commit-deferred and local schedules rigorous to assure global serializability of the multidatabase system. In this paper, we define dynamic-serializability and some classes of safe schedules which are recoverable from failure of transactions. Using them we give different, something weaker constraints, while global serializability of the multidatabase system is still achieved

The chicken fast skeletal troponin I gene: exon organization and sequence.

The gene encoding the fast skeletal isoform of the chick troponin I (sTnI) protein has been sequenced and its organization into exons and introns established. The gene is approximately 4.5 kb in length and composed of 8 exons, the first of which contains solely 5' untranslated sequence. In addition to its major mRNA product, there is evidence that the sTnI gene encodes a second mRNA, present at low abundance levels in embryonic skeletal muscle. Sl nuclease protection and primer extension experiments indicate that the low abundance mRNA is initiated approximately 47 nucleotides upstream of the major transcriptional initiation site. Both mRNAs appear to encode identical sTnI polypeptides. A comparison of nucleotide sequence in the 5' flanking region of several muscle-specific genes, including the sTnI gene, reveals a heptanucleotide consensus sequence, 5'-CATTCCT-3', which is conserved in the 5' flanking regions of many vertebrate contractile protein genes