49,264 research outputs found
Problems of the Dual in Soqotri
Problems of the Dual in Soqotripublished or submitted for publicationis peer reviewe
USING PRIMARY AND SECONDARY DATA TO CONSTRUCT AN INPUT-OUTPUT TABLE--A CASE STUDY OF FOUR CITIES IN NORTHEASTERN MINNESOTA AND DOUGLAS COUNTY, WISCONSIN
The purpose of this paper is report on the construction of the thirty-five sector input-output table which represents the interindustry flows in a four-city area. The incorporated areas of the cities of Duluth, Two Harbors, and Cloquet in Minnesota, and Superior in Wisconsin are included in the study.Community/Rural/Urban Development,
Exploration of RNA structure spaces
In order to understand the structure of real structure spaces, we are studying the 5S rRNA structure space experimentally. A plasmid containing a synthetic 5S rRNA gene, two rRNA promoters, and transcription terminators has been assembled. Assays are conducted to determine if the foreign 5S rRNA is expressed, and to see whether or not it is incorporated into ribosomes. Evolutionary competition is used to determine the relative fitness of strains containing the foreign 5S rRNA and a control 5S rRNA. By using site directed mutagenesis, a number of mutants can be made in order to study the boundaries of the structure space and how sharply defined they are. By making similar studies in the vicinity of structure space, it will be possible to determine how homogeneous the 5S rRNA structure space is. Useable experimental protocols have been developed, and a number of mutants have already been studied. Initial results suggest an explanation of why single stranded regions of the RNA are less subject to mutation than double stranded regions
Insights into the phylogenetic positions of photosynthetic bacteria obtained from 5S rRNA and 16S rRNA sequence data
Comparisons of complete 16S ribosomal ribonucleic acid (rRNA) sequences established that the secondary structure of these molecules is highly conserved. Earlier work with 5S rRNA secondary structure revealed that when structural conservation exists the alignment of sequences is straightforward. The constancy of structure implies minimal functional change. Under these conditions a uniform evolutionary rate can be expected so that conditions are favorable for phylogenetic tree construction
Appropriate Classification of Obesity in Mentally Retarded Adults
Triceps skinfold thickness and body weight measures were obtained for 44 female and 40 male mentally retarded adults participating in a sheltered workshop setting. Subiects\u27 relative weights and skinfold thicknesses were found to correlate reasonably well for females and males, rs = .88 and .59, respectively. Use of only height and weight tables for determining the presence of obesity, however, resulted in 22.5 percent of the males and 13 .7 percent of the females being misclassified as nonobese. The distinction between overweight and obesity was discussed. Clinical/research implications of the findings were delineated
Parenting Latino Toddlers and Preschoolers: Clinical and Nonclinical Samples
Parenting practices contribute significantly to the social-emotional development of young children. There is limited literature that addresses the role of culture in parenting, particularly among Latino families who have very young children with significant behavior problems. The current study compared the parenting practices of 30 low-income Latino mothers whose young children had been referred for mental health services for their behavior problems with a similar group of 30 mothers of children without behavior problems. Results showed that mothers in the clinical sample nurtured their children less often and used more frequent verbal and corporal punishment as discipline than the nonclinical sample. The clinical sample also had a significantly higher incidence of mental health problems in their families. Results also showed the significant toll that raising young children with challenging behaviors takes on their mothers. The implications of these findings for the early identification of these children are discussed
ENVIRONMENTAL POLICY CONSIDERATIONS IN THE GRAIN-LIVESTOCK SUBSECTORS IN CANADA, MEXICO AND THE UNITED STATES
Environmental Economics and Policy,
Speaker-normalized sound representations in the human auditory cortex
The acoustic dimensions that distinguish speech sounds (like the vowel differences in “boot” and “boat”) also differentiate speakers’ voices. Therefore, listeners must normalize across speakers without losing linguistic information. Past behavioral work suggests an important role for auditory contrast enhancement in normalization: preceding context affects listeners’ perception of subsequent speech sounds. Here, using intracranial electrocorticography in humans, we investigate whether and how such context effects arise in auditory cortex. Participants identified speech sounds that were preceded by phrases from two different speakers whose voices differed along the same acoustic dimension as target words (the lowest resonance of the vocal tract). In every participant, target vowels evoke a speaker-dependent neural response that is consistent with the listener’s perception, and which follows from a contrast enhancement model. Auditory cortex processing thus displays a critical feature of normalization, allowing listeners to extract meaningful content from the voices of diverse speakers
Generalised knot groups distinguish the square and granny knots (with an appendix by David Savitt)
Given a knot K we may construct a group G_n(K) from the fundamental group of
K by adjoining an nth root of the meridian that commutes with the corresponding
longitude. These "generalised knot groups" were introduced independently by
Wada and Kelly, and contain the fundamental group as a subgroup. The square
knot SK and the granny knot GK are a well known example of a pair of distinct
knots with isomorphic fundamental groups. We show that G_n(SK) and G_n(GK) are
non-isomorphic for all n>1. This confirms a conjecture of Lin and Nelson, and
shows that the isomorphism type of G_n(K), n>1, carries more information about
K than the isomorphism type of the fundamental group. An appendix by David
Savitt contains some results on representations of the trefoil group in
PSL(2,p) that are needed for the proof.Comment: 25 pages, 5 figures, to appear in JKTR. v3: example of the target
groups added; slight correction to the construction of the target groups;
references updated; some changes to notation. v2: section 4.2 expanded to
give overview of proo
- …