255 research outputs found
Blink rate measured in situ decreases while reading from printed text or digital devices, regardless of task duration, difficulty or viewing distance
Purpose: To compare blinking measured in situ during various tasks and examine relationships with ocular surface symptoms. The day-to-day repeatability of the blink rate and interblink interval was assessed
The individual context of ultrasonic vocalizations in wild monogamous California mice (Peromyscus californicus).
Ultrasonic vocalizations (USVs) are commonly produced by the rodent species in the Super Family Muroidea. The bulk of USV research has been conducted on Mus and Rattus exclusively in a laboratory setting. There is variation in the production and function of USVs between Mus and Rattus as a result of contrasting social structures. Peromyscus californicus is an obligately monogamous species that regularly produces USVs. The objective of my study is to determine the context of USV production in free
living P. californicus in California. I investigated motif use and spectral and temporal
characteristics of USV as they related to sex, and estrous state. I determined when pairs
produced USVs as well as the individuals present when USVs were produced. I looked at the production of USVs in response to sub-adult dispersal and I compared the variation between pairs with the variation within pairs. The most commonly recorded USV motifs were 1-4 syllable vocalizations. Sex and estrous state were independent of motif type and the spectral characteristics of USVs did not differ between males and females or estrous and non-estrous females. Pairs never vocalized when they were in contact and motif type was independent of individuals present on the focal area. The majority of USVs were recorded during the breeding season, however, USV production was highly positively correlated with sub-adult dispersal (Pearson’s correlation 0.79). While I did not find a difference between pairs or individuals within a pair, my analysis suggests that the difference between pairs is more significant than the difference between individuals within a pair. My results suggest USVs reinforce pairbonds and advertise a pair’s
territory. Peromyscus californicus is an excellent model for monogamy in mammals and
USVs are an important component of P. californicus behavior in the wild
Pervasiveness of use and adequacy of care labels for piece good fabrics
This study attempted to provide a basis for evaluating the effectiveness of the Care Labeling Rule in the piece goods market. There were two main objectives: (1) to determine if care labels are available and distributed with piece goods at the point of sale in the retail market; and (2) to determine if care labels supply adequate and accurate information. To accomplish the first objective, 49 stores were selected in the Greensboro and Winston-Salem, North Carolina, and Washington, D. C. areas for the survey. These stores included a representative selection of department, discount and specialty stores selling piece goods. The researcher observed in each store to determine the types of fabrics consumers were purchasing and the availability of care labels. Thirty-four samples of fabric representative of consumer purchases were secured for testing to determine if the care labels were adequate and accurate. All of the samples were designated to be refurbished under home laundry conditions. These were laundered as indicated by the care label or by standard household conditions in the absence of a label. The performance of fabrics was tested by modified standard procedures to determine color transfer, color loss, change in appearance, dimensional stability and loss of strength. These results were compared to minimum performance standards (MPS) established by the researcher
Perceptions of central office personnel on the role of the principal as curriculum leader
The purpose of this study was to investigate the perception of central office persons concerning the role of principals as CURRICULUM leaders. This investigation considered the independent variables of central office persons' prior experience as principal, involvement in professional curriculum organizations, awareness of current literature in curriculum and instruction through up-to-date reading, and the perception central office persons hold toward their own role in the central office. Data were obtained from a sample of 110 responses to a questionnaire mailed to the total population of 141 central office persons responsible for curricular and instructional programs in the local school system. Data were analyzed according to five questions asked by the study regarding perceptions of the total number of central office persons on the role of principals with whom they work and principals across North Carolina, and correlations of the four independent variables on the dependent variable. A chi square test was conducted for each set of data and variables significant at the .01 confidence level were determined
Style in Malory's book of Balin
The purpose of this study is to reveal the beginning of Malory's selfconscious artistry as it is exhibited in his book of Balin. I attempt to reveal this through an examination of his prose style, primarily by viewing the changes lie makes in his French source. In the first chapter I define style as not only syntax and the arrangement of words out also narrative structural devices. The second chapter deals with these narrative structural devices. In the third, fourth and fifth chapters I examine the stylistic techniques Malory uses in his narration, description and dialogue. The final chapter looks at "Balin" and its relationship to "The Tale of King Arthur" and the entire Le Morte Darthur
Revisions In United Nations Energy Statistics Data: Can Changes To The Past Improve Our Understanding Of The Present?
Before data can be analyzed effectively, it needs to be evaluated to determine its quality. With the rise in interest in combating global climate change by reducing carbon dioxide (CO2) emissions, understanding data quality and certainty is important for producing accurate estimates of emissions from fossil fuel combustion and other industrial processes. These estimates are essential for monitoring the prospects and progress towards national targets for reduction. Accurate fossil fuel CO2 (FFCO2) estimates, along with climate modeling and current atmospheric conditions, are also essential to forecast future global temperatures. Most fossil CO2 emissions inventories rely on energy statistics to generate country and year specific estimates of CO2. Every year, the United Nations publishes an updated Energy Statistics Database that provides annual statistics on the production, processing, trade, and use of fuels for over 230 countries, going back as far as 1950. Each subsequent publication of the database provides additional entries and updated values to the previous years’ data. This opens up questions about these data revisions: what changes are taking place, how are countries revising their data, and are there recognizable patterns that provide information to anticipate changes in future database releases? The purpose of this thesis is to learn from the revisions to address questions and concerns surrounding this Energy Statistics Database. This begins with an investigation into the changes occurring in the datasets year-to-year and ends with an inference into patterns within these changes. The additional insight this presents allows a deeper level of understanding for where in the database revisions are occurring, to better characterize the uncertainty of present CO2 value estimates
Secular evolution versus hierarchical merging: galaxy evolution along the Hubble sequence, in the field and rich environments
In the current galaxy formation scenarios, two physical phenomena are invoked
to build disk galaxies: hierarchical mergers and more quiescent external gas
accretion, coming from intergalactic filaments. Although both are thought to
play a role, their relative importance is not known precisely. Here we consider
the constraints on these scenarios brought by the observation-deduced star
formation history on the one hand, and observed dynamics of galaxies on the
other hand: the high frequency of bars and spirals, the high frequency of
perturbations such as lopsidedness, warps, or polar rings.
All these observations are not easily reproduced in simulations without
important gas accretion. N-body simulations taking into account the mass
exchange between stars and gas through star formation and feedback, can
reproduce the data, only if galaxies double their mass in about 10 Gyr through
gas accretion. Warped and polar ring systems are good tracers of this
accretion, which occurs from cold gas which has not been virialised in the
system's potential. The relative importance of these phenomena are compared
between the field and rich clusters. The respective role of mergers and gas
accretion vary considerably with environment.Comment: 18 pages, 8 figures, review paper to "Penetrating Bars through Masks
of Cosmic Dust: the Hubble Tuning Fork Strikes a New Note", Pilanesberg, ed.
D. Block et al., Kluwe
Methods for specifying the target difference in a randomised controlled trial : the Difference ELicitation in TriAls (DELTA) systematic review
Peer reviewedPublisher PD
Colouration in amphibians as a reflection of nutritional status : the case of tree frogs in Costa Rica
Colouration has been considered a cue for mating success in many species; ornaments in males often are related to carotenoid mobilization towards feathers and/or skin and can signal general health and nutrition status. However, there are several factors that can also link with status, such as physiological blood parameters and body condition, but there is not substantial evidence which supports the existence of these relationships and interactions in anurans. This study evaluated how body score and blood values interact with colouration in free-range Agalychnis callidryas and Agalychnis annae males. We found significant associations between body condition and plasmatic proteins and haematocrit, as well as between body condition and colour values from the chromaticity diagram. We also demonstrated that there is a significant relation between the glucose and plasmatic protein values that were reflected in the ventral colours of the animals, and haematocrit inversely affected most of those colour values. Significant differences were found between species as well as between populations of A. callidryas, suggesting that despite colour variation, there are also biochemical differences within animals from the same species located in different regions. These data provide information on underlying factors for colouration of male tree frogs in nature, provide insights about the dynamics of several nutrients in the amphibian model and how this could affect the reproductive output of the animals
Education and training of healthcare staff in the knowledge, attitudes and skills needed to work effectively with breastfeeding women:a systematic review
BACKGROUND: Current evidence suggests that women need effective support to breastfeed, but many healthcare staff lack the necessary knowledge, attitudes and skills. There is therefore a need for breastfeeding education and training for healthcare staff. The primary aim of this review is to determine whether education and training programs for healthcare staff have an effect on their knowledge and attitudes about supporting breastfeeding women. The secondary aim of this review was to identify whether any differences in type of training or discipline of staff mattered. METHODS: A systematic search of the literature was conducted using the Cochrane Pregnancy and Childbirth Group’s trial register. Randomised controlled trials comparing breastfeeding education and training for healthcare staff with no or usual training and education were included if they measured the impact on staff knowledge, attitudes or compliance with the Baby Friendly Hospital Initiative (BFHI). RESULTS: From the 1192 reports identified, four distinct studies were included. Three studies were two-arm cluster-randomised trials and one was a two-arm individual randomised trial. Of these, three contributed quantitative data from a total of 250 participants. Due to heterogeneity of outcome measures meta-analysis was not possible. Knowledge was included as an outcome in two studies and demonstrated small but significant positive effects. Attitudes towards breastfeeding was included as an outcome in two studies, however, results were inconsistent both in terms of how they were measured and the intervention effects. One study reported a small but significant positive effect on BFHI compliance. Study quality was generally deemed low with the majority of domains being judged as high or unclear risk of bias. CONCLUSIONS: This review identified a lack of good evidence on breastfeeding education and training for healthcare staff. There is therefore a critical need for research to address breastfeeding education and training needs of multidisciplinary healthcare staff in different contexts through large, well-conducted RCTs
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