Several Explanations (several + explanation)

Distribution by Scientific Domains


Selected Abstracts


An Exploratory Analysis of the Value of the Skills of IT Personnel: Their Relationship to IS Infrastructure and Competitive Advantage

DECISION SCIENCES, Issue 1 2001
Terry Anthony Byrd
Abstract Determining and assessing the requisite skills of information technology (IT) personnel have become critical as the value of IT has risen in modern organizations. In addition to technical skills traditionally expected of IT personnel, softer skills like managerial, business, and interpersonal skills have been increasingly cited in previous studies as mandatory for these employees. This paper uses a typology of IT personnel skills,technology management skills, business functional skills, interpersonal skills, and technical skills,and investigates their relationships to two information systems (IS) success variables, IS infrastructure flexibility and the competitive advantage provided by IS. The study investigates these relationships using the perceptions of chief information officers (CIOs) from mostly Fortune 2000 companies. The contributions of this study are: IT personnel skills do affect IS success, technical skills are viewed as the most important skill set in affecting IS infrastructure flexibility and competitive advantage, and modularity is viewed as more valuable to competitive advantage than integration. Several explanations are offered for the lack of positive relationships between the softer IT personnel skills and the dimensions of IS success used in this study. [source]


Effect of toothpaste on the plaque inhibitory properties of a cetylpyridinium chloride mouth rinse

JOURNAL OF CLINICAL PERIODONTOLOGY, Issue 3 2003
S. Sheen
Abstract Background and aims: Cetylpyridinium chloride (CPC) mouth rinses have moderate plaque inhibitory activity when used alone but rarely have shown adjunctive benefits to tooth brushing with toothpaste. Several explanations for this apparent anomaly can be proferred, including loss of antiseptic activity due to interactions with toothpaste ingredients. The aim of this study was to measure the effect of toothpaste on the plaque inhibitory properties of a CPC mouth rinse using paired rinses of CPC, toothpaste slurry (TP) and water (W). Methods: The study was a single blind, randomised, seven-treatment, cross over design balanced for residual effects, involving 21 healthy, dentate subjects. The paired rinses were: W-CPC, CPC-W, TP-CPC, CPC-TP, W-TP, TP-W and W-W. Rinsing with solutions or slurries was done for 60 s twice per day. On day 1, subjects were rendered plaque free, suspended tooth cleaning and commenced the allocated rinse regimen. On day 5, plaque was scored by index. A 2½ day wash out of normal oral hygiene was allowed between each regimen. Results: The order from lowest to highest plaque scores was as follows: W-CPC = CPC-W < CPC-TP < TP-CPC , W-TP < TP-W < W-W. Several differences in pairs of treatments were statistically significant, the most relevant of which were significantly less plaque with W-CPC compared to TP-CPC, TP-W and W-TP, and significantly more plaque with W-W compared to all other regimens except TP-W. Conclusions: Toothpaste, whilst possessing some plaque inhibitory activity, when used immediately before a CPC mouth rinse adversely affected the plaque inhibitory action of this antiseptic. This in part may explain the reported lack of adjunctive benefits of CPC rinses to normal oral hygiene practices and supports the suggestion, made for chlorhexidine rinses, that their use should follow toothpaste by at least 60 min. Zusammenfassung Die Wirkung von Zahnpasta auf die plaquehemmenden Eigenschaften einer Mundspüllösung mit Cetylpyridinium-Chlorid Grundlagen und Ziel: Cetylpyridinium-Chlorid (CPC) Mundspüllösung haben, wenn sie alleine verwendet werden, eine moderate plaquehemmende Aktivität. Es wurde jedoch selten gezeigt, dass sie zusätzlich zum Zähneputzen Vorteile haben. Mehrere Erklärungen für diese offensichtliche Anomalie können angeboten werden, einschließlich des Verlusts der antiseptischen Aktivität wegen einer Interaktion mit Inhaltstoffen der Zahnpasta. Ziel dieser Studie war es, die Wirkung der Zahnpasta auf die plaquehemmenden Eigenschaften einer CPC-Mundspüllösung zumessen. Es wurde CPC zusammen mit Zahnpasta-Lösung (TP) oder zusammen mit Wasser (W) verwendet. Methoden: Die randomisierte, einfach-blinde-Studie hatte ein 7-Behandlungs- Crossover-Design und war ausgeglichen hinsichtlich der Resteffekte. Einundzwanzig gesunde und bezahnte Personen wurden aufgenommen. Die paarweisen Spülungen waren: W-CPC, CPC-W, TP-CPC, CPC-TP, W-TP, TP-W und W-W. Die Spülungen wurden zweimal pro Tag für 60 Sekunden durchgeführt. An Tag-1 wurde bei der Teilnehmern Plaquefreiheit hergestellt, sie enthielten sich der Mundhygiene und begannen die zugewiesenen Spülungen. An Tag-5 wurde die Plaque mittels Index beurteilt. Zwischen den Spülmaßnahmen war eine 2,5-tägige Auswaschperiode mit normaler Mundhygiene erlaubt. Ergebnisse: Die Reihenfolge vom niedrigsten zum höchsten Plaquewert war W-CPC = CPC-W < CPC-TP < TP-CPC [source]


Part-time workers and economic expansion: comparing the 1980s and 1990s with U.S. state data,

PAPERS IN REGIONAL SCIENCE, Issue 1 2003
Mark D. Partridge
Part-time employment; involuntary part-time; regional labor markets; labor shortages Abstract. Economics know little about how the role of part-time workers affect regional labor market dynamics during economic expansion. This study examines this issue using U.S. state data from the 1980s and 1990s. Compared to the 1980s, the labor market during the late 1990s is associated with widespread labor shortages, making this an excellent comparison of how part-time employment responds to economic growth. One key finding is that part-time employment was less responsive to job growth during the 1990s than the 1980s, especially for women. Several explanations are put forth, including firm responses to labor shortages, employer perceptions of inferior part-time worker characteristics and welfare reform. [source]


Sex differences in the events that elicit jealousy among homosexuals

PERSONAL RELATIONSHIPS, Issue 1 2001
PIETERNEL DIJKSTRA
When individuals are asked which event would upset them more,a partner's emotional infidelity or a partner's sexual infidelity,among heterosexuals more men than women select a partner's sexual infidelity as the most distressing event, whereas more women than men select a partner's emotional infidelity as the most upsetting event. Because homosexuals'mating psychology is unlike that of heterosexuals, the present study examined which of these two events is more upsetting in a sample of 237 Dutch homosexuals. In support of our hypothesis it was found that, whereas gay men more often than lesbian women chose a mate's emotional infidelity as the most upsetting event, lesbians more often than gay men chose a mate's sexual infidelity as the most upsetting event. In addition, analyses showed that the effect of participant sex on infidelity choice was mediated by beliefs with regard to the co-occurrence of sexual and emotional infidelity. Apparently, with respect to choosing the most upsetting type of infidelity of their partner, homosexuals resemble heterosexuals of the opposite sex. Several explanations are discussed for this finding. [source]


Efficiency droop in nitride-based light-emitting diodes

PHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 10 2010
Joachim Piprek
Abstract Nitride-based light-emitting diodes (LEDs) suffer from a reduction (droop) of the internal quantum efficiency with increasing injection current. This droop phenomenon is currently the subject of intense research worldwide, as it delays general lighting applications of GaN-based LEDs. Several explanations of the efficiency droop have been proposed in recent years, but none is widely accepted. This feature article provides a snapshot of the present state of droop research, reviews currently discussed droop mechanisms, contextualizes them, and proposes a simple yet unified model for the LED efficiency droop. Illustration of LED efficiency droop (details in Fig. 13). [source]


Discrimination of temporal synchrony in intermodal events by children with autism and children with developmental disabilities without autism

THE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 1 2006
James M. Bebko
Background:, This project examined the intermodal perception of temporal synchrony in 16 young children (ages 4 to 6 years) with autism compared to a group of children without impairments matched on adaptive age, and a group of children with other developmental disabilities matched on chronological and adaptive age. Method:, A preferential looking paradigm was used, where participants viewed non-linguistic, simple linguistic or complex linguistic events on two screens displaying identical video tracks, but one offset from the other by 3 seconds, and with the single audio track matched to only one of the displays. Results:, As predicted, both comparison groups demonstrated significant non-random preferential looking to violations of temporal synchrony with linguistic and non-linguistic stimuli. However, the group with autism showed an impaired, chance level of responding, except when presented with non-linguistic stimuli. Conclusions:, Several explanations are offered for this apparently autism-specific, language-specific pattern of responding to temporal synchrony, and potential developmental sequelae are discussed. [source]


Seedling establishment, mortality, tree growth rates and vigour of Acacia nilotica in different Astrebla grassland habitats: Implications for invasion

AUSTRAL ECOLOGY, Issue 3 2002
Ian J. Radford
Abstract A demographic study was conducted in the northern Australian Astrebla grasslands to determine the importance of habitat type in influencing invasion patterns of Acacia nilotica, an exotic leguminous tree from Africa and Asia. One of the repeated patterns observed for A. nilotica is that denser populations are often associated with riparian habitats. Data available on this species do not enable us to determine which of a number of processes has lead to the formation of this pattern. Several explanations were tested for patterns in tree abundance: (i) that more seedlings emerge in wetter habitats; (ii) that mortality is lower in wetter habitats; (iii) that growth rates are faster in wetter habitats; and (iv) that plants are more vigorous (as indicated by leaf cover, flowering intensity and predation rates) over longer periods in wetter habitats. The study was stratified across three habitat types, perennial and ephemeral riparian and non-riparian, which are characteristic of Astrebla grasslands and differentiated by the availability of water. In addition to testing for habitat-linked differentiation in demography, data were also used to test whether seedling emergence, mortality, growth and vigour varied between sites with cattle versus sheep. The data collected indicated that seedling emergence, determined primarily by livestock dispersal, was likely to be the dominant influence on patterns of A. nilotica invasion. Mortality and growth rates were similar in ephemeral riparian and non-riparian habitats, whereas perennial riparian habitats had more rapid growth rates, which may increase the rate of invasion in these areas. Plant vigour was also greater over longer periods in perennial riparian habitats with greater leaf cover, longer flowering season and fewer insect borer holes. Livestock species were found to have little influence on the demography of A. nilotica plants in this study. Very low growth rates and high mortality in A. nilotica populations are likely to lead to net decline in ephemeral riparian and non-riparian habitats in the long term. The importance of episodic recruitment in the maintenance of A. nilotica populations is discussed. [source]


Climate, size and flowering history determine flowering pattern of an orchid

BOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 4 2006
MARION PFEIFER
The flowering pattern of plant species, including orchid species, may fluctuate irregularly. Several explanations are given in the literature to explain that pattern, including: costs associated with reproduction, herbivory effects, intrinsically triggered unpredictable variation of the system, and external conditions (i.e. weather). The influence of age is discussed, but is difficult to determine because relevant long-term field observations are generally absent in the literature. The influence of age, size, reproductive effort and climatic conditions on flowering variability of Himantoglossum hircinum are examined using data collected in a long-term project (1976,2001) in Germany. PCA and multiple regression analysis were used to analyse variability in flowering pattern over the years as a function of size and weather variability. We studied future size after flowering to quantify costs of reproduction. Flowering probability was strongly determined by plant size, while there was no significant influence of age class on flowering probability of the population. Costs associated with reproduction resulted in a decrease in plant size, causing reduced flowering probability of the plants in the following year. The weather explained about 50% of the yearly variation in the proportion of large plants and thus had an indirect, strong influence on the flowering percentage. We conclude that variability in flowering is caused mainly by the variability of weather conditions in the previous and current year, whereby reproductive effort causes further variability in flowering at the individual and, consequently, the population levels. © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society, 2006, 151, 511,526. [source]


The relationship between education and health behavior: some empirical evidence

HEALTH ECONOMICS, Issue 2 2006
Alexander J. Cowell
Abstract Although researchers agree that more educated people typically engage in healthier behaviors, they have not uncovered the reason why. This paper considers several explanations, including future opportunity costs. Future opportunity costs represent any utility-improving future outcome that is affected by currently engaging in health-related behavior. This paper also examines whether there are degree effects in the health behaviors of binge drinking and smoking. Results suggest that future opportunity costs may affect smoking, although other interpretations cannot be ruled out. The results also find degree effects with regard to binge drinking. Copyright © 2005 John Wiley & Sons, Ltd. [source]


GPS tracking of the foraging movements of Manx Shearwaters Puffinus puffinus breeding on Skomer Island, Wales

IBIS, Issue 3 2008
T. C. GUILFORD
We report the first successful use of miniature Global Positioning System loggers to track the ocean-going behaviour of a c. 400 g seabird, the Manx Shearwater Puffinus puffinus. Breeding birds were tracked over three field seasons during the incubation and chick-rearing periods on their foraging excursions from the large colony on Skomer Island, Pembrokeshire, UK. Foraging effort was concentrated in the Irish Sea. Likely foraging areas were identified to the north, and more diffusely to the west of the colony. No foraging excursions were recorded significantly to the south of the colony, conflicting with the conclusions of earlier studies based on ringing recoveries and observations. We discuss several explanations including the hypothesis that foraging may have shifted substantially northwards in recent decades. We found no obvious relationship between birds' positions and water depth, although there was a suggestion that observations at night were in shallower water than those during the day. We also found that, despite the fact that Shearwaters can be observed rafting off-shore from their colonies in the hours prior to making landfall at night, breeding birds are usually located much further from the colony in the last 8 h before arrival, a finding that has significance for the likely effectiveness of marine protection areas if they are only local to the colony. Short sequences of precise second-by-second fixes showed that movement speeds were bimodal, corresponding to sitting on the water (most common at night and around midday) and flying (most common in the morning and evening), with flight behaviour separable into erratic (indicative of searching for food) and directional (indicative of travelling). We also provide a first direct measurement of mean flight speed during directional flight (c. 40 km/h), slower than a Shearwater's predicted maximum range velocity, suggesting that birds are exploiting wave or dynamic soaring during long-distance travel. [source]


Does the relationship between IgE and the CD14 gene depend on ethnicity?

ALLERGY, Issue 11 2008
G. Zhang
This review considers the data from studies analysing associations between the CD14C,159T single nucleotide polymorphism (SNP) and asthmatic phenotypes and discusses the variability of the conclusions. By searching PubMed and EMBASE for articles on CD14C,159T -related population or family-based association studies, 47 were identified up till September 2007. Collectively, the studies reviewed herein consistently showed population differences in frequencies of the alleles of the SNP, with African descent having the highest C allele frequencies, followed by Caucasians and Asians. The T allele of the SNP was associated with increased sCD14 in some studies but not in others. Inconsistently, the C allele, or even occasionally the T allele, was associated with atopic phenotypes in a population subgroup. There are several explanations for these inconsistencies, including lack of power, linkage disequilibrium, gene,gene interactions, population admixture and gene,environment interactions. If the SNP was associated with functional changes to the coded protein and thus modulating susceptibility to allergic disease, its effect may be modest and dependent on other co-existent, ethnicity-specific, genetic or environmental risk factors. [source]


Partisanship, Political Control, and Economic Assessments

AMERICAN JOURNAL OF POLITICAL SCIENCE, Issue 1 2010
Alan S. Gerber
Previous research shows that partisans rate the economy more favorably when their party holds power. There are several explanations for this association, including use of different evaluative criteria, selective perception, selective exposure to information, correlations between economic experiences and partisanship, and partisan bias in survey responses. We use a panel survey around the November 2006 election to measure changes in economic expectations and behavioral intentions after an unanticipated shift in political power. Using this design, we can observe whether the association between partisanship and economic assessments holds when some leading mechanisms thought to bring it about are excluded. We find that there are large and statistically significant partisan differences in how economic assessments and behavioral intentions are revised immediately following the Democratic takeover of Congress. We conclude that this pattern of partisan response suggests partisan differences in perceptions of the economic competence of the parties, rather than alternative mechanisms. [source]