Psychometric Properties of Scores from the Web-Based LibQUAL+ Study of Perceptions of Library Service Quality

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Users' Perceptions of Library Service Quality: A LibQUAL+ Qualitative Study

published or submitted for publicatio

Comparative ultrastructure of plasmodesmata of Chara and selected bryophytes: towards an elucidation of the evolutionary origin of plant plasmodesmata

We have used transmission electron microscopy to examine plasmodesmata of the charophycean green alga Chara zeylanica, and of the putatively early divergent bryophytes Monoclea gottschei (liverwort), Notothylas orbicularis (hornwort), and Sphagnum fimbriatum (moss), in an attempt to learn when seed plant plasmodesmata may have originated. The three bryophytes examined have desmotubules. In addition, Monoclea was found to have branched plasmodesmata, and plasmodesmata of Sphagnum displayed densely staining regions around the neck region, as well as ring-like wall specializations. In Chara, longitudinal sections revealed endoplasmic reticulum (ER) that sometimes appeared to be associated with plasmodesmata, but this was rare, despite abundant ER at the cell periphery. Across all three fixation methods, cross-sectional views showed an internal central structure, which in some cases appeared to be connected to the plasma membrane via spoke-like structures. Plasmodesmata were present even in the incompletely formed reticulum of forming cell plates, from which we conclude that primary plasmodesmata are formed at cytokinesis in Chara zeylanica. Based on these results it appears that plasmodesmata of Chara may be less specialized than those of seed plants, and that complex plasmodesmata probably evolved in the ancestor of land plants before extant lineages of bryophytes diverged

Penalized Ordinal Regression Methods for Predicting Stage of Cancer in High-Dimensional Covariate Spaces

The pathological description of the stage of a tumor is an important clinical designation and is considered, like many other forms of biomedical data, an ordinal outcome. Currently, statistical methods for predicting an ordinal outcome using clinical, demographic, and high-dimensional correlated features are lacking. In this paper, we propose a method that fits an ordinal response model to predict an ordinal outcome for high-dimensional covariate spaces. Our method penalizes some covariates (high-throughput genomic features) without penalizing others (such as demographic and/or clinical covariates). We demonstrate the application of our method to predict the stage of breast cancer. In our model, breast cancer subtype is a nonpenalized predictor, and CpG site methylation values from the Illumina Human Methylation 450K assay are penalized predictors. The method has been made available in the ordinalgmifs package in the R programming environment

Identifying Molecular Features Associated with Psychoneurological Symptoms in Women with Breast Cancer Using Multivariate Mixed Models

Breast cancer (BC) is the second most common cancer among women. Research shows many women with BC experience anxiety, depression, and stress (ADS). Epigenetics has recently emerged as a potential mechanism for the development of depression.1 Although there are growing numbers of research studies indicating that epigenetic changes are associated with ADS, there is currently no evidence that this association is present in women with BC. The goal of this study was to identify high-throughput methylation sites (CpG sites) that are associated with three psychoneurological symptoms (ADS) in women with BC. Traditionally, univariate models have been used to examine the relationship between methylation sites and each psychoneurological symptom; nevertheless, ADS can be treated as a cluster of related symptoms and included together in a multivariate linear model. Hence, an overarching goal of this study is to compare and contrast univariate and multivariate models when identifying methylation sites associated with ADS in women with BC. When fitting separate linear regression models for each ADS scale, 3 among 285,173 CpG sites tested were significantly associated with depression. Two significant CpG sites are located on their respective genes FAM101A and FOXJ1, and the third site cannot be mapped to any known gene at this time. In contrast, the multivariate models identified 8,535 ADS-related CpG sites. In conclusion, when analyzing correlated psychoneurological symptom outcomes, multivariate models are more powerful and thus are recommended

DRIVING ON EMPTY: EXPLORING PRINCIPAL BURNOUT AND INTENT TO TURNOVER

This study used a quantitative design analyzing extant data from the NTPS distributed by the National Center for Education Statistics (NCES). This is a national survey distributed to principals to gather information about the principalship, individual factors, and organizational factors for the school they lead. Using extant data, analyses were conducted to examine the relationships among individual factors, situational factors, and overall levels of burnout. Overall, 17.5% to 19% of the public school principals across the nation reported experiencing feelings of burnout. While there was a moderate level of burnout reported, principals were generally satisfied with their role, reporting an overall satisfaction score of 3.39 on a 1-4 scale (1 being strongly disagree and 4 being strongly agree). Both individual and situational factors were associated with reported burnout levels. When considering individual factors; younger principals, principals with more experience, and White principals reported higher levels of burnout. Additionally, situational factors both increased and decreased reported levels of burnout. Principals with more influence on decision making, those able to work on curriculum, and those with higher salaries reported lower levels of burnout. On the other hand, school problems and the number of hours worked in a week were related to increased levels of burnout

Fluency Interventions and the Impact on Comprehension

Reading fluency is understood to be the rate and accuracy of that which is being read and comprehension is the understanding of what has been read. Many studies support the concept that fluency skills support reading comprehension. Many students with specific learning disabilities lack the fluency skills needed for successful reading comprehension. This study provided fluency interventions to elementary students with specific learning disabilities and evaluated any comprehension gains. Students graphed their own fluency gains during the interventions and a pre-test and post-test were given to monitor comprehension. There was in increase in both the average fluency rate for each group and the average comprehension scores, however, the increases in comprehension were not a statistically significant amount

The Effects of Soil pH and Texture on the Molting Success and Survival of Blacklegged Ticks (Ixodes scapularis): A Field Experiment

The blacklegged tick (Ixodes scapularis) is the primary vector of Borrelia burgdorferi, the causative agent of Lyme disease. When a tick is not questing or feeding, the majority of its life is spent within the soil. Abiotic factors within soil have been shown to affect tick molting and survival across all life stages. Soil pH, however, has not been heavily investigated. In this field study, I investigated the effects of soil pH and texture on engorged nymphal ticks. Two sites were chosen to encompass the extremes of soil pH in the region; the Albany Pine Bush in Albany, NY has acidic, loam soils and Wolf Hollow in Schenectady, NY has more alkaline, silt-loam soils. In July 2013, four plots, each containing three treatments (undisturbed soil/unaltered pH, disturbed soil/unaltered pH, and disturbed soil/altered pH), were placed at each site. Engorged nymphs were collected from chipmunks and placed within soil cores in each plot. Tick body burden data on the chipmunks was also collected and analyzed, revealing that scrotal males had significantly higher body burdens than non-scrotal males. Tick drags were also conducted at the end of July, confirming that the Albany Pine Bush had higher tick densities. In October 2013, the cores were removed and searched for surviving adult ticks. Although there was significant variation in survival, neither pH nor texture explained the pattern. The disappearances of ticks combined with finding insects within the cores suggest an avenue for further research

Perceived Stress Levels, Chemotherapy, Radiation Treatment and Tumor Characteristics Are Associated with a Persistent Increased Frequency of Somatic Chromosomal Instability in Women Diagnosed with Breast Cancer: A One Year Longitudinal Study

While advances in therapeutic approaches have resulted in improved survival rates for women diagnosed with breast cancer, subsets of these survivors develop persistent psychoneurological symptoms (fatigue, depression/anxiety, cognitive dysfunction) that compromise their quality of life. The biological basis for these persistent symptoms is unclear, but could reflect the acquisition of soma-wide chromosomal instability following the multiple biological/psychological exposures associated with the diagnosis/treatment of breast cancer. An essential first step toward testing this hypothesis is to determine if these cancer-related exposures are indeed associated with somatic chromosomal instability frequencies. Towards this end, we longitudinally studied 71 women (ages 23-71) with early-stage breast cancer and quantified their somatic chromosomal instability levels using a cytokinesis-blocked micronuclear/cytome assay at 4 timepoints: before chemotherapy (baseline); four weeks after chemotherapy initiation; six months after chemotherapy (at which time some women received radiotherapy); and one year following chemotherapy initiation. Overall, a significant change in instability frequencies was observed over time, with this change differing based on whether the women received radiotherapy (p=0.0052). Also, significantly higher instability values were observed one year after treatment initiation compared to baseline for the women who received: sequential taxotere/doxorubicin/cyclophosphamide (pp=0.014). Significant predictive associations for acquired micronuclear/cytome abnormality frequencies were also observed for race (p=0.0052), tumor type [luminal B tumors] (p=0.0053), and perceived stress levels (p=0.0129). The impact of perceived stress on micronuclear/cytome frequencies was detected across all visits, with the highest levels of stress being reported at baseline (p =0.0024). These findings suggest that the cancer-related exposome has an impact on both healthy somatic cells and tumor cells, and may lead to persistent chromosomal instability. In addition, stress was a significant predictor of chromosomal instability; thus, interventions that aim to reduce stress may reduce acquired soma-wide chromosomal instability for cancer survivors