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Positive Direction (positive + direction)
Selected AbstractsElectrical penetration graphs of the nymphal stage of Bemisia argentifoliiENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 2 2003Y.X. Jiang Abstract Electrical penetration graph (EPG, DC system) waveforms were recorded from first, second, and third instar Bemisia argentifolii nymphs. Waveforms recorded were similar among the three instars. Four waveforms were recorded and were named C, J, L, and H. Waveform J is new, whereas waveforms C, L, and H of B. argentifolii nymphs were similar to those published previously from greenhouse whitefly nymphs. As in the previous study on greenhouse whitefly nymphs, there was variation in each of waveforms C, L, and H. Waveform C was recorded at an extracellular voltage level, and represents a pathway phase where the stylets penetrate the plant tissue in an intercellular pathway. At the end of waveform C, the voltage dropped to an intracellular level, indicating penetration of a living cell, and the stylet tips then remained in that cell for the rest of the EPG recording, which was sometimes as long as 16 h. Three waveforms (J, L, and H) were recorded during this intracellular phase, beginning with J, a brief (average = 31 s), low amplitude, irregular waveform. J appeared only at the beginning of the intracellular phase, and was followed by either L (five out of eight times) or H (three out of eight times). Waveforms L and H then alternated with one another for the remainder of the intracellular phase. The most conspicuous difference between L and H was the frequency of their voltage fluctuations; L had a lower frequency and H a higher frequency. Usually the shape of waveform L was dominated by voltage peaks in a positive direction, while waveform H was characterized by strong voltage peaks in a negative direction; although some variants of both L and H had distinct voltage peaks in both directions. The electrical origin of both the positive and negative voltage peaks was electromotive force (emf) fluctuation rather than resistance fluctuation. During waveform H, copious amounts of honeydew were produced, indicating that the penetrated cell was a sieve element. We conclude, therefore, that H represents phloem sap ingestion; and because J and L are produced in the same cell as H, then phloem phase is represented by waveforms J, L, and H. The biological correlations for J and L are not yet known. [source] Changes in externalizing and internalizing behaviours over a school-year: differences between 6-year-old boys and girlsINFANT AND CHILD DEVELOPMENT, Issue 2 2006Annie Hammarberg Abstract The purpose of this study was to investigate changes in externalizing and internalizing problem behaviours in 6-year-olds with a focus on sex differences. Teachers rated problem behaviours at the beginning and at the end of the school year, 8 months apart, in 370 children (197 boys and 173 girls) attending 22 school preparatory classrooms. Although the majority of the children were quite stable, considerable negative and positive changes for both boys and girls in problem behaviours were found. The results showed that girls were more likely to change their externalizing behaviours in a positive direction than boys, whereas a tendency to the opposite pattern was found for internalizing behaviours. Boys were also found to be more prone to a negative change in problem behaviours of both types than girls were. Copyright © 2006 John Wiley & Sons, Ltd. [source] Temporal changes in the affective experience of new fathers and their spousesINFANT MENTAL HEALTH JOURNAL, Issue 6 2004Marsha Kaitz Our aim was to study temporal changes in fathers' affective experience during the first year of parenthood. For comparison, data also were collected from their spouses. Fifty-five Israeli couples comprised the initial sample, and both partners were interviewed during the prepartum period and at 3, 6, and 12 months' postpartum. Measures of emotionality, positive affect, negative affect, and mood regarding self, infant, and spouse/marriage were derived by finely coding parents' answers to interview questions. Analyses show that, for fathers and mothers, time effects were most substantial between the prepartum period and 3 months postpartum, and most of the changes were in a positive direction. Fathers and mothers showed continuity in positive affect and in negative affect, respectively. Overall, the sample experienced heightened positive affect and more positive moods after the birth of their infant than prior to it. [source] The impact of personal characteristics on engagement in nursing home residents with dementiaINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 7 2009Jiska Cohen-Mansfield Abstract Objective To examine the impact of personal attributes on engagement in persons with dementia. Methods Participants were 193 residents of seven Maryland nursing homes. All participants had a diagnosis of dementia. Cognitive functioning was assessed via the Mini-Mental State Examination, and engagement was assessed via the Observational Measure of Engagement. Data pertaining to activities of daily living were obtained from the Minimum Data Set. Results Women had longer mean engagement duration than men, and significant results were not seen with the other demographic variables. Significant, positive correlations were found between higher cognitive functioning and longer engagement duration, more attention, a more positive attitude, and a higher refusal rate. There was a positive and significant correlation between the comorbidity index and engagement duration, and between the number of medications and attention. All functional status variables yielded significance in a positive direction. Participants with poor hearing had a higher refusal rate. Cognitive status was the most consistent and potent predictor of engagement in this population. Conclusion Despite a higher refusal rate among those with higher cognitive levels, their overall engagement with stimuli is higher. Caregivers should anticipate higher refusal rates in those with poor hearing, and therefore compensatory methods should be used in presenting stimuli in this population. The potent role of cognitive and functional status on engagement of persons with dementia underscores the importance of tailoring activities to nursing home residents' needs, interests, and limitations. Copyright © 2009 John Wiley & Sons, Ltd. [source] From Theory to Practice: General Trends in Foreign Language Teaching Methodology and Their Influence on Language AssessmentLINGUISTICS & LANGUAGE COMPASS (ELECTRONIC), Issue 6 2007Christine Campbell In the late 1970s, language-learning theorists redefined ability in a second or foreign language, emphasizing its communicative aspects. The proficient linguist was one who could function effectively in the four skills of speaking, writing, reading comprehension, and listening comprehension in real-life, not contrived or artificial, contexts. This new paradigm led to change in language-teaching methodology; communicative language teaching became the prevailing approach. From that time through the present, developments in language-teaching methodology have both informed trends in language assessment and been influenced by them. One recent pivotal development has been the creation and implementation of the national standards for foreign language learning. The product of both theorists and practitioners, the standards broadened the concept of ability to include the capacity to perform in 11 standards that fall under five goal areas: communication, cultures, connections, comparisons, and communities. However, although the original standards describe the content of instruction, they do not specify performance standards for each of the 11 content standards or provide assessments. As a result, the profession has had to rise to the challenge of producing standards-based assessments in K-16. Select state and school district programs have devised model assessments; others are gradually following suit. With the standards as a catalyst, both teaching and testing will undoubtedly continue to evolve in a positive direction. [source] Testability and repair of hereditary hypergraph propertiesRANDOM STRUCTURES AND ALGORITHMS, Issue 4 2010Tim Austin Abstract Recent works of Alon,Shapira (A characterization of the (natural) graph properties testable with one-sided error. Available at: http://www.math.tau.ac.il/,nogaa/PDFS/heredit2.pdf) and Rödl,Schacht (Generalizations of the removal lemma, Available at: http://www.informatik.hu-berlin.de/,schacht/pub/preprints/gen_removal.pdf) have demonstrated that every hereditary property of undirected graphs or hypergraphs is testable with one-sided error; informally, this means that if a graph or hypergraph satisfies that property "locally" with sufficiently high probability, then it can be perturbed (or "repaired") into a graph or hypergraph which satisfies that property "globally." In this paper we make some refinements to these results, some of which may be surprising. In the positive direction, we strengthen the results to cover hereditary properties of multiple directed polychromatic graphs and hypergraphs. In the case of undirected graphs, we extend the result to continuous graphs on probability spaces and show that the repair algorithm is "local" in the sense that it only depends on a bounded amount of data; in particular, the graph can be repaired in a time linear in the number of edges. We also show that local repairability also holds for monotone or partite hypergraph properties (this latter result is also implicitly in (Ishigamis work Removal lemma for infinitely-many forbidden hypergraphs and property testing. Available at: arXiv.org: math.CO/0612669)). In the negative direction, we show that local repairability breaks down for directed graphs or for undirected 3-uniform hypergraphs. The reason for this contrast in behavior stems from (the limitations of) Ramsey theory. © 2010 Wiley Periodicals, Inc. Random Struct. Alg., 2010 [source] A systematic approach to the derivation of standard orientation-location parts of symmetry-operation symbolsACTA CRYSTALLOGRAPHICA SECTION A, Issue 6 2007Kazimierz Stró Automatically generated orientation-location parts, or coordinate triplets describing the geometric elements, differ frequently from the corresponding parts of the symmetry-operation symbols listed in International Tables for Crystallography [(1983), Vol. A, Space-Group Symmetry, edited by Th. Hahn. Dordrecht: Reidel]. An effective algorithm enabling the derivation of standard orientation-location parts from any symmetry matrix is described and illustrated. The algorithm is based on a new concept alternative to the `invariant points of reduced operation'. First, the geometric element that corresponds to a given symmetry operation is oriented and located in a nearly convention free manner. The application of the direction indices [uvw] or Miller indices (hkl) gives a unique orientation provided the convention about the positive direction is defined. The location is fixed by the specification of a unique point on the geometric element, i.e. the point closest to the origin. Next, both results are converted into the standard orientation-location form. The standardization step can be incorporated into other existing methods of derivation of the symmetry-operation symbols. A number of standardization examples are given. [source] Attachment in low-SES rural Appalachian infants: Contextual, infant, and maternal interaction risk and protective factorsINFANT MENTAL HEALTH JOURNAL, Issue 6 2001Margaret Fish Attachment classifications were obtained for 95 low-socioeconomic-status (SES) rural Appalachian infants in the Strange Situation procedure at 15 months. The distribution of secure (B) and insecure (A, C, D) infants was similar to other low-SES samples and significantly different from low-risk samples. Levels of contextual and infant risk, together with maternal responsiveness to crying and pattern of sensitivity from 4 to 9 months, predicted attachment security. High social support, when examined as a protective factor, related to reduced contextual risk, but not to increased likelihood of security. Exploratory discriminant function analyses showed that infants in secure relationships differed in positive directions on contextual and maternal interactional factors. Insecure-organized (A and C) infants experienced contextual and maternal interaction risks, while insecure-disorganized (D) infants were best distinguished by infant characteristics, including greater likelihood of being male and low use of mother as a secure base at 9 months. ©2001 Michigan Association for Infant Mental Health. [source] Variation of dust endotoxin concentrations by location and time within homes of young childrenPEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 3 2010Dennis R. Ownby Ownby DR, Peterson EL, Williams LK, Zoratti EM, Wegienka GR, Woodcroft KJ, Joseph CLM, Johnson CC. Variation of dust endotoxin concentrations by location and time within homes of young children. Pediatr Allergy Immunol 2010: 21: 533,540. © 2010 John Wiley & Sons A/S Endotoxin may affect the development of allergic disease in childhood but little is known about endotoxin variation within homes. We sought to determine endotoxin concentration agreement within homes when five locations were each sampled twice 5 months apart. Endotoxin was measured using the recombinant Limulus factor C assay in dust samples from 585 homes of children enrolled in a prospective study and again in 335 homes 5 months later. The five locations sampled in each home were the child's bedroom floor, child's bed, mother's bedroom floor, mother's bed and living room floor. Concentrations of 4 allergens (Can f 1, Fel d 1, Der f 1 and Bla g 2) were also measured from the child's bedroom floor. In pair-wise comparisons, endotoxin concentrations in all locations within each home were significantly different from all other locations (p < 0.001) except for the child's and mother's bedroom floors (p = 0.272). Spearman correlations between endotoxin concentrations from the different locations were all statistically significant (p < 0.05) but of modest magnitude (r = 0.24,0.54). Similarly, correlations at each site over the 5 month observation interval were statistically significant but modest (r = 0.17,0.44). Pets and season of the year did not affect correlations, although correlations were lower if the floor was not carpeted. Endotoxin concentrations at all locations were minimally correlated with allergen concentrations in both negative and positive directions (r = ,0.12 to 0.12). We conclude that a single measurement of endotoxin from a home dust sample provides an imprecise estimate of dust endotoxin concentrations in other locations within the home and over a relatively short observation interval. [source] | |||||||||||||