168 research outputs found
Student-teacher relationship as a moderator of the relation between classroom behavior and reading achievement
Extant research documents associations between child classroom behavior and reading achievement as well as the associations between student-teacher relationships and children's reading success. Less is known about how all three of these variables may develop and influence one another together, and virtually no research has examined these issues with populations of young students living in rural communities. The current study examined a moderation model of reading achievement in which student-teacher relationship was expected to moderate the relations between fall classroom behavior of rural kindergarten and first grade students and their spring reading achievement. Using a hierarchical linear regression model, child demographic characteristics and beginning levels of reading achievement were controlled for and models predicting both phonological and comprehension skills were examined. Results indicate a significant but weak and un-interpretable interaction between classroom behavior and student-teacher relationship in predicting phonological skills. No interaction was found in predicting comprehension scores
Psychometric Evaluation and Design of Patient-Centered Communication Measures for Cancer Care Settings
Objective
To evaluate the psychometric properties of questions that assess patient perceptions of patient-provider communication and design measures of patient-centered communication (PCC). Methods
Participants (adults with colon or rectal cancer living in North Carolina) completed a survey at 2 to 3 months post-diagnosis. The survey included 87 questions in six PCC Functions: Exchanging Information, Fostering Health Relationships, Making Decisions, Responding to Emotions, Enabling Patient Self-Management, and Managing Uncertainty. For each Function we conducted factor analyses, item response theory modeling, and tests for differential item functioning, and assessed reliability and construct validity. Results
Participants included 501 respondents; 46% had a high school education or less. Reliability within each Function ranged from 0.90 to 0.96. The PCC-Ca-36 (36-question survey; reliability=0.94) and PCC-Ca-6 (6-question survey; reliability=0.92) measures differentiated between individuals with poor and good health (i.e., known-groups validity) and were highly correlated with the HINTS communication scale (i.e., convergent validity). Conclusion
This study provides theory-grounded PCC measures found to be reliable and valid in colorectal cancer patients in North Carolina. Future work should evaluate measure validity over time and in other cancer populations. Practice implications
The PCC-Ca-36 and PCC-Ca-6 measures may be used for surveillance, intervention research, and quality improvement initiatives
Do I have something in my teeth? The trouble with genetic analyses of diet from archaeological dental calculus
Dental calculus and other preserved microbiome substrates are an attractive target for dietary reconstruction in past populations through a variety of physical, chemical, and molecular means. Recently, studies have attempted to reconstruct diet from archaeological dental calculus using archaeogenetic techniques. While dental calculus may provide a relatively stable environment for DNA preservation, the detection of plants and animals possibly consumed by an individual through DNA analysis is primarily hindered by microbial richness and incomplete reference databases. Moreover, high genomic similarity within eukaryotic groups - such as mammals - can obfuscate precise taxonomic identification. In the current study we demonstrate the challenges associated with accurate taxonomic identification and authentication of dietary taxa in ancient DNA data using both synthetic and ancient dental calculus datasets. We highlight common errors and sources of contamination across ancient DNA datasets, provide recommendations for dietary DNA validation, and call for caution in the interpretation of diet from dental calculus and other archaeological microbiome substrates.J.A.F.Y. was partially funded by the European Research Council (ERC) under the European Union's Horizon 2020 research innovation programme (ERC-2015-StG 678901-FoodTransforms to Philipp W. Stockhammer, Ludwig Maximilian University Munich, Germany). Z.F. was supported by the Werner Siemens Stiftung through Dr. Christina Warinner. This research was supported in part through computational resources provided by the Department of Archaeogenetics at the Max Planck Institute for the Science of Human History (J.A.F.Y).Ye
The efficacy of whole human genome capture on ancient dental calculus and dentin
Objectives: Dental calculus is among the richest known sources of ancient DNA in the archaeological record. Although most DNA within calculus is microbial, it has been shown to contain sufficient human DNA for the targeted retrieval of whole mitochondrial genomes. Here, we explore whether calculus is also a viable substrate for whole human genome recovery using targeted enrichment techniques. Materials and methods: Total DNA extracted from 24 paired archaeological human dentin and calculus samples was subjected to whole human genome enrichment using in-solution hybridization capture and high-throughput sequencing. Results: Total DNA from calculus exceeded that of dentin in all cases, and although the proportion of human DNA was generally lower in calculus, the absolute human DNA content of calculus and dentin was not significantly different. Whole genome enrichment resulted in up to fourfold enrichment of the human endogenous DNA content for both dentin and dental calculus libraries, albeit with some loss in complexity. Recovering more on-target reads for the same sequencing effort generally improved the quality of downstream analyses, such as sex and ancestry estimation. For nonhuman DNA, comparison of phylum-level microbial community structure revealed few differences between precapture and postcapture libraries, indicating that off-target sequences in human genome-enriched calculus libraries may still be useful for oral microbiome reconstruction. Discussion: While ancient human dental calculus does contain endogenous human DNA sequences, their relative proportion is low when compared with other skeletal tissues. Whole genome enrichment can help increase the proportion of recovered human reads, but in this instance enrichment efficiency was relatively low when compared with other forms of capture. We conclude that further optimization is necessary before the method can be routinely applied to archaeological samples
The keys to healthy family child care homes intervention: Study design and rationale
Obesity is a major public health problem for which early preventive interventions are needed. Large numbers of young children are enrolled in some form of child care program, making these facilities influential environments in children’s development. Family child care homes (FCCH) are a specific type of child care in which children are cared for within the provider’s own residence. FCCHs serve approximately 1.5 million children in the U.S.; however, research to date has overlooked FCCH providers and their potential to positively influence children’s health-related behaviors
Perdigão 2015: methodology for atmospheric multi-Doppler lidar experiments
The long-range and short-range WindScanner systems (LRWS and SRWS),
multi-Doppler lidar instruments, when combined together can map the turbulent
flow around a wind turbine and at the same time measure mean flow conditions
over an entire region such as a wind farm. As the WindScanner technology is
novel, performing field campaigns with the WindScanner systems requires a
methodology that will maximize the benefits of conducting WindScanner-based
experiments. Such a methodology, made up of 10 steps, is presented and discussed
through its application in a pilot experiment that took place in a complex
and forested site in Portugal, where for the first time the two WindScanner
systems operated simultaneously. Overall, this resulted in a detailed site
selection criteria, a well-thought-out experiment layout, novel flow mapping
methods and high-quality flow observations, all of which are presented in
this paper
Planet Populations as a Function of Stellar Properties
Exoplanets around different types of stars provide a window into the diverse
environments in which planets form. This chapter describes the observed
relations between exoplanet populations and stellar properties and how they
connect to planet formation in protoplanetary disks. Giant planets occur more
frequently around more metal-rich and more massive stars. These findings
support the core accretion theory of planet formation, in which the cores of
giant planets form more rapidly in more metal-rich and more massive
protoplanetary disks. Smaller planets, those with sizes roughly between Earth
and Neptune, exhibit different scaling relations with stellar properties. These
planets are found around stars with a wide range of metallicities and occur
more frequently around lower mass stars. This indicates that planet formation
takes place in a wide range of environments, yet it is not clear why planets
form more efficiently around low mass stars. Going forward, exoplanet surveys
targeting M dwarfs will characterize the exoplanet population around the lowest
mass stars. In combination with ongoing stellar characterization, this will
help us understand the formation of planets in a large range of environments.Comment: Accepted for Publication in the Handbook of Exoplanet
Evaluating the Sensitivity of Mycobacterium tuberculosis to Biotin Deprivation Using Regulated Gene Expression
In the search for new drug targets, we evaluated the biotin synthetic pathway of Mycobacterium tuberculosis (Mtb) and constructed an Mtb mutant lacking the biotin biosynthetic enzyme 7,8-diaminopelargonic acid synthase, BioA. In biotin-free synthetic media, ΔbioA did not produce wild-type levels of biotinylated proteins, and therefore did not grow and lost viability. ΔbioA was also unable to establish infection in mice. Conditionally-regulated knockdown strains of Mtb similarly exhibited impaired bacterial growth and viability in vitro and in mice, irrespective of the timing of transcriptional silencing. Biochemical studies further showed that BioA activity has to be reduced by approximately 99% to prevent growth. These studies thus establish that de novo biotin synthesis is essential for Mtb to establish and maintain a chronic infection in a murine model of TB. Moreover, these studies provide an experimental strategy to systematically rank the in vivo value of potential drug targets in Mtb and other pathogens
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