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This research investigates the types of revisions students make to position-time graphs they construct. In our online graphing unit, students construct position-time graphs and then revise their graphs after receiving various forms of feedback. We examine how and why students attempt to revise their graphs, finding that students continue to have difficulty with constructing and revising position-time graphs. We then suggest areas for support in the future design of guidance for graph construction.

AIMS: To compare the prevalence of minor incisional complications in canine patients undergoing tibial plateau levelling osteotomy (TPLO) surgery that had a hydrogel liquid bandage (HLB) applied to their incision, with patients that had a light adhesive bandage applied. METHODS: Thirty dogs undergoing TPLO surgery were randomly assigned to either application of a light adhesive bandage to the incision, with removal 18–24 hours later, or application of a clear-drying polyethylene glycol HLB to the incision. Erythema, swelling, discharge, and dehiscence were assessed 1 day (Day 1) and 10–14 days (Days 10–14) postoperatively. All persons completing the assessment were blinded to the treatment. Outcomes were compared for the two groups using Fisher’s Exact Test. RESULTS: On both Day 1 and Days 10–14, the distribution of dogs with erthemyma or swelling did not differ between the two groups (p≥0.4). The prevalence of erythema was the same in the bandage and HLB groups at Day 1 (11/15; 73%) and was similar at Days 10–14 (3/11 (27%) and 2/11 (18%), respectively). Prevalence of swelling was also the same in the two groups on Day 1 (11/15; 73%) and was similar at Days 10–14 (3/11 (27%) and 6/11 (55%), respectively). On Day 1, 2/15 (13%) dogs in the HLB group and none of the dogs in the bandage group had incisional discharge (p=0.483). No dogs were observed with discharge on Days 10–14. No dehiscence, infection, or any other major incisional complication was observed in either group at any point in the study. CONCLUSIONS: Preliminary results suggest that prevalence of minor incisional complications after TPLO surgery treated with HLB or with a traditional adhesive bandage may be comparable. No major adverse effects were seen with the use of HLB. CLINICIAL RELEVANCE: Due to several disadvantages of traditional bandaging, which can require post-operative maintenance and removal, lasts only a short time, and be painful when removed, an alternative with fewer drawbacks is desirable. HLB may present such an alternative. [ABSTRACT FROM AUTHOR]

Background: As of this present moment, there is paucity of data on report concerning the association between hypoalbuminaemia or reversal of albumin-to-globulin ratio and morbidity outcome in Lassa fever (LF) infection as a crucial determinant prognostic-predictor factor for treatment-survival outcome. Aim: This study was designed to determine the association between hypoalbuminaemia, reversal of albumin-to-globulin ratio and morbidity outcome among confirmed LF infected patients. Methodology: This was a descriptive retrospective study involving the assessment of records of confirmed LF infected patients that were managed at the center from November 2018 to October 2019. Results: Out of 83 recruited participants with complete records, 66 (79.5%) had hypoalbuminaemia, 74 (89.2%) had reversal of albumin-to-globulin ratio. A higher mean value of total white blood cell (WBC) count was observed among patients with hypoalbuminaemia (p

Circadian rhythms organize many aspects of cell biology and physiology to a daily temporal program that depends on clock gene expression cycles in most mammalian cell types. However, circadian rhythms are also observed in isolated mammalian red blood cells (RBCs), which lack nuclei, suggesting the existence of post-translational cellular clock mechanisms in these cells. Here we show using electrophysiological and pharmacological approaches that human RBCs display circadian regulation of membrane conductance and cytoplasmic conductivity that depends on the cycling of cytoplasmic K + levels. Using pharmacological intervention and ion replacement, we show that inhibition of K + transport abolishes RBC electrophysiological rhythms. Our results suggest that in the absence of conventional transcription cycles, RBCs maintain a circadian rhythm in membrane electrophysiology through dynamic regulation of K + transport.

In animals, piRNAs and their associated Piwi proteins guard germ cell genomes against mobile genetic elements via an RNAi-like mechanism. In Caenorhabditis elegans, 21U-RNAs comprise the piRNA class, and these collaborate with 22G RNAs via unclear mechanisms to discriminate self from nonself and selectively and heritably silence the latter. Recent work indicates that 21U-RNAs are post-transcriptional processing products of individual transcription units that produce ∼ 26-nucleotide capped precursors. However, nothing is known of how the expression of precursors is controlled or how primary transcripts give rise to mature small RNAs. We conducted a genome-wide RNAi screen to identify components of the 21U biogenesis machinery. Screening by direct, quantitative PCR (qPCR)-based measurements of mature 21U-RNA levels, we identified 22 genes important for 21U-RNA production, termed TOFUs (Twenty-One-u Fouled Ups). We also identified seven genes that normally repress 21U production. By measuring mature 21U-RNA and precursor levels for the seven strongest hits from the screen, we assigned factors to discrete stages of 21U-RNA production. Our work identifies for the first time factors separately required for the transcription of 21U precursors and the processing of these precursors into mature 21U-RNAs, thereby providing a resource for studying the biogenesis of this important small RNA class.

Meehl's (1973, Psychodiagnosis: Selected papers. Minneapolis: University of Minnesota Press) distinction between statistical and clinical significance holds special relevance for evidence-based neuropsychological practice. Meehl argued that despite attaining statistical significance, many published findings have limited practical value since they do not inform clinical care. In the context of an ever expanding clinical research literature, accessible methods to evaluate clinical impact are needed. The method of Critically Appraised Topics (Straus, Richardson, Glasziou, & Haynes, 2011, Evidence-based medicine: How to practice and teach EBM (4th ed.). Edinburgh: Elsevier Churchill-Livingstone) was developed to provide clinicians with a "toolkit" to facilitate implementation of evidence-based practice. We illustrate the Critically Appraised Topics method using a dementia screening example. We argue that the skills practiced through critical appraisal provide clinicians with methods to: (1) evaluate the clinical relevance of new or unfamiliar research findings with a focus on patient benefit, (2) help focus of research quality, and (3) incorporate evaluation of clinical impact into educational and professional development activities.

We describe a novel method of estimating reduced bone mineral density (BMD) from dental panoramic tomograms (DPTs), which show the entire mandible. Careful expert width measurement of the inferior mandibular cortex has been shown to be predictive of BMD in hip and spine osteopenia and osteoporosis. We have implemented a method of automatic measurement of the width by active shape model search, using as training data 132 DPTs of female subjects whose BMD has been established by dual-energy X-ray absorptiometry. We demonstrate that widths measured after fully automatic search are significantly correlated with BMD, and exhibit less variability than manual measurements made by different experts. The correlation is highest towards the lateral region of the mandible, in a position different from that previously employed for manual width measurement. An receiver-operator characterstic (ROC) analysis for identifying osteopenia (T < -1: BMD more than one standard deviation below that of young healthy females) gives an area under curve (AUC) value of 0.64. Using a minimal interaction to initiate active shape model (ASM) search, the measurement can be made at the optimum region of the mandible, resulting in an AUC value of 0.71. Using an independent test set, AUC for detection of osteoporosis (T < -2.5) is 0.81.

There is consensus to use the bone mineral density (BMD) for the operational definition of the degree of osteoporosis and the risk of osteoporotic fractures. Dual X-ray absorptiometry (DXA) is the common technique to determine BMD. Because of high costs and limited availability of DXA equipment it is worthwhile to look for alternative diagnostic techniques. As part of a larger study, the Osteodent project, we investigated if the trabecular pattern on dental radiographs can be used to predict BMD and to identify the subjects with osteoporosis and increased risk of osteoporotic fractures. In four clinical centers 671 women with an average age of 55 years were recruited. BMD values were measured by DXA equipment at the femoral neck, total hip, and spine. One panoramic and two intraoral radiographs were made. From 525 women a complete set of BMD values and radiographs was obtained. Four regions of interest on the radiographs were selected manually and then processed automatically. On all regions of interest mean and standard deviation of the gray values were measured and several features describing the shape of the binarized trabecular pattern. Multiple regression was used to predict BMD of total hip and spine by means of the radiographic measurements combined with age. It was found that age accounts for 10% of the variation in total hip BMD and 14% of the variation in spinal BMD. When all measurements on the dental radiographs are used the explained variation increases to 22% and 23%. The areas under the ROC curves are comparable to those of commonly used screening instruments for osteoporosis. It is concluded that prediction of DXA measurements of BMD by means of quantitative analysis of the trabecular pattern on dental radiographs is feasible.

A method proffered for the interpretation of measurements from peripheral dual energy X-ray absorptiometry (pDXA) is a triage approach to stratify patients into one of three risk categories; (i) high-treat, (ii) medium-refer for central DXA and (iii) low-reassure. The aim of this study was to apply the triage approach to measures from peripheral scanners and risk indices and stratify patients into one of three risk categories (i), (ii) or (iii). 207 post-menopausal women had central DXA from which they were categorised as non-osteoporotic or osteoporotic. Additional peripheral scans of the left calcaneus were performed on three scanners (GE Lunar Achilles and PIXI, McCue CubaClinical). From demographic details four risk indices were calculated and algorithms combining measures from peripheral scanners and one risk index were obtained. All peripheral measures, risk indices and combination algorithms were good at identifying women at risk of osteoporosis (ROC areas: 0.67-0.82). Each tool stratified varying numbers of osteoporotic and non-osteoporotic women into each risk category using the triage approach. One combination algorithm (PIXI & osteoporosis indices of risk (OSIRIS)) performed best by minimising misclassification (10% non-osteoporotic, 10% osteoporotic) and reducing requirement for central DXA to 36%. However the cost of implementing the triage approach for PIXI & OSIRIS was greater (263%) than central DXA (100%) scanning all women. Although the triage approach was an effective tool at identifying women at risk of osteoporosis the unnecessary treatment of non-osteoporotic women in the high risk category make it impractical. Therefore an alternative more cost-effective method has been suggested.

The high precision and stable calibration of dual X-ray absorptiometry (DXA) scanners have led to their widespread use in longitudinal studies for research and the follow-up of individual patients who are receiving treatment for osteoporosis. However, difficulties in maintaining the continuity of the bone mineral density (BMD) calibration scale can arise when an old DXA system is replaced by a newer model. We report the results of an in vivo cross-calibration study performed when a GE-Lunar Prodigy fan-beam system replaced a DPX-L pencil-beam scanner. Lumbar spine and hip DXA scans were performed in 133 patients (104 female, 29 male) attending long-term BMD monitoring. On average, lumbar spine BMD measurements on the two systems agreed closely, with Prodigy values 1% lower than those on the DPX-L. However, after allowing for this difference, the root mean square error (RMSE) of 0.037 g/cm2 was larger than in previous cross-calibration studies reported in the literature, and was 3 times the value expected from the precision of the BMD measurements. Mean femoral neck BMD also agreed closely between the two systems, although for Prodigy, the spread of measurements was 10% smaller than that for the DPX-L. For the trochanter and Ward's triangle regions, mean BMD was 4% and 6% lower, respectively, on the Prodigy system, and the results were affected by a similar compression of the range of values. RMSE values were 0.037 g/cm2, 0.044 g/cm2, and 0.044 g/cm2, respectively, for the femoral neck, trochanter, and Ward's triangle sites. When the high value of the RMSE was investigated, it was found that for lumbar spine BMD, patient body weight and the difference between the two systems in the percentage fat reported in the soft tissue reference region explained 40% of the variance. This enabled equations to be developed that significantly improved the agreement between scans performed on the two systems. Smaller improvements were obtained for the femur BMD measurements.

The study assessed the precision, sensitivity, and specificity of a recently developed peripheral dual-energy X-ray absorptiometry (DXA) scanner, applied to the calcaneus, in the identification of individuals with osteoporosis at axial sites by DXA. Two hundred and two women, aged 55.2 +/- l3.7 years (mean +/- SD), participated in the study. The precisions (coefficient of variation) of measurements in vitro (0.48%) and in vivo (1.40%) were very good. The in vivo precision was independent of the operator, foot size, foot width, weight, height, and body mass index. Calcaneus BMD correlated moderately (r = 0.494-0.690, P <0.001) with axial BMD measurements by DXA. Using the World Health Organization (WHO) criterion for defining osteoporosis (T score ? -2.5) the specificity of the calcaneus to identify patients with osteoporosis at total hip, femoral neck, spine, or any of these axial sites was excellent (97.0%, 97.0%, 96.5%, and 97.1%, respectively); however, the sensitivity was poor (58.8%, 36.4%, 21.8%, and 20.3%, respectively). Therefore, the WHO criterion is not appropriate for DXA calcaneus. Based on femoral neck BMD for detection of osteoporosis, a more appropriate calcaneus T score threshold would be -1.4 by analyses of receiver-operator characteristic curves; this might serve to select those patients who might appropriately be referred for axial DXA.

Grainyhead belongs to a recently identified group of transcription factors which share a 250-amino-acid domain required for binding to DNA and a carboxy-terminal dimerization domain. The activities of Grainyhead and other members of the family appear to be modulated so that they can participate in different developmental processes. We have examined the structure and function of mRNAs from the Drosophila grainyhead gene and demonstrated that alternate splicing is responsible for generating a neuroblast-specific isoform of the protein. A mutation which abolishes this isoform results in pupal and adult lethality. Reporter genes containing different Grainyhead binding sites exhibit tissue-specific patterns of expression that correlate with the Grainyhead isoforms, suggesting that the alternate splicing serves to alter the repertoire of target genes controlled in the neuroblasts.

The neurotransmitter serotonin has a profound effect on the control of sleep; thus excess serotonin activity in the brain could be responsible for impaired consciousness in hepatic encephalopathy. Furthermore, an increased brain level of 5-hydroxy-indoleacetic acid has been a consistent finding in various animal models of the condition. In this study, using high-performance liquid chromatography with fluorometric detection, we examined levels of brain serotonin (5-hydroxytryptamine) and its precursors and metabolites in 16 patients dying with hepatic encephalopathy complicating acute and chronic liver disease and 9 control subjects matched for age, sex, postmortem delay in brain retrieval and length of frozen tissue storage. In patients with chronic liver disease, serotonin level was significantly increased in thalamus (p < 0.02); levels of its metabolite 5-hydroxyindoleacetic acid were increased in frontal cortex (p < 0.05), globus pallidus (p < 0.05) and putamen (p < 0.01). Levels of the precursor amino acid tryptophan were increased in thalamus (p < 0.01) and globus pallidus (p < 0.01); in both patient groups levels of 5-hydroxytryptophan and the tryptamine metabolite indoleacetic acid were increased in all brain areas studied. 5-Hydroxytryptamine levels were also increased in thalamus, frontal cortex and globus pallidus in the three patients with fulminant liver failure. Our findings are consistent with disordered neurotransmission, especially in the thalamus, an area of particular importance in the regulation of consciousness, alertness and attention in human beings.