Implementation of a point-of-care ultrasound skills practicum for hospitalists

Introduction Point-of-care ultrasound is recognized as a safe and valuable diagnostic tool for patient evaluation. Hospitalists are prime candidates for advancing the point-of-care ultrasound field given their crucial role in inpatient medicine. Despite this, there is a notable lack of evidence-based ultrasound training for hospitalists. Most research focuses on diagnostic accuracy rather than the training required to achieve it. This study aims to improve hospitalists' point-of-care ultrasound knowledge and skills through a hands-on skills practicum. Methods Four skill practicums were conducted with pre-course, post-course, and six-month evaluations and knowledge assessments. Results The mean pre- vs. post-course knowledge assessment scores significantly improved, 41.7% vs. 75.9% (SD 16.1% and 12.7%, respectively, p < 0.0001). The mean ultrasound skills confidence ratings on a 10-point Likert scale significantly increased post-course (2.60 ± 1.66 vs. 6.33 ± 1.63, p < 0.0001), but decreased at six months (6.33 ± 1.63 vs. 4.10 ± 2.22, p < 0.0001). The greatest limitations to usage pre-course and at six months were knowledge/skills and lack of machine access. While knowledge/skills decreased from pre-course (82.0%) as compared to six-months (64.3%), lack of machine access increased from pre-course (15.8%) to six-months (28.6%) (p = 0.28). Conclusion Hospitalists agree that point-of-care ultrasound has utility in the diagnostic and therapeutic management of patients, though the lack of training is a significant limitation. Our study demonstrated that a brief skills practicum significantly improves hospitalists’ confidence and knowledge regarding ultrasound image acquisition and interpretation in the short term. Long-term confidence and usage wanes, which appears to be due to the lack of machine access

Mercury in the environment

Problems in assessing mercury concentrations in environmental materials are discussed. Data for situations involving air, water, rocks, soils, sediments, sludges, fossil fuels, plants, animals, foods, and man are drawn together and briefly evaluated. Details are provided regarding the toxicity of mercury along with tentative standards and guidelines for mercury in air, drinking water, and food

Electronic Correlation and Transport Properties of Nuclear Fuel Materials

Actinide elements, such as uranium and plutonium, and their compounds are best known as nuclear materials. When engineering optimal fuel materials for nuclear power, important thermophysical properties to be considered are melting point and thermal conductivity. Understanding the physics underlying transport phenomena due to electrons and lattice vibrations in actinide systems is a crucial step toward the design of better fuels. Using first principle LDA+DMFT method, we conduct a systematic study on the correlated electronic structures and transport properties of select actinide carbides, nitrides, and oxides, many of which are nuclear fuel materials. We find that different mechanisms, electrons--electron and electron--phonon interactions, are responsible for the transport in the uranium nitride and carbide, the best two fuel materials due to their excellent thermophysical properties. Our findings allow us to make predictions on how to improve their thermal conductivities.Comment: Main article: 5 pages, 3 figures. Supplementary info: 2 pages, 1 figur

Algorithmic aspects of disjunctive domination in graphs

For a graph $G=(V,E)$, a set $D\subseteq V$ is called a \emph{disjunctive dominating set} of $G$ if for every vertex $v\in V\setminus D$, $v$ is either adjacent to a vertex of $D$ or has at least two vertices in $D$ at distance $2$ from it. The cardinality of a minimum disjunctive dominating set of $G$ is called the \emph{disjunctive domination number} of graph $G$, and is denoted by $\gamma_{2}^{d}(G)$. The \textsc{Minimum Disjunctive Domination Problem} (MDDP) is to find a disjunctive dominating set of cardinality $\gamma_{2}^{d}(G)$. Given a positive integer $k$ and a graph $G$, the \textsc{Disjunctive Domination Decision Problem} (DDDP) is to decide whether $G$ has a disjunctive dominating set of cardinality at most $k$. In this article, we first propose a linear time algorithm for MDDP in proper interval graphs. Next we tighten the NP-completeness of DDDP by showing that it remains NP-complete even in chordal graphs. We also propose a $(\ln(\Delta^{2}+\Delta+2)+1)$-approximation algorithm for MDDP in general graphs and prove that MDDP can not be approximated within $(1-\epsilon) \ln(|V|)$ for any $\epsilon>0$ unless NP $\subseteq$ DTIME$(|V|^{O(\log \log |V|)})$. Finally, we show that MDDP is APX-complete for bipartite graphs with maximum degree $3$

Familial correlates of adolescent girls' physical activity, television use, dietary intake, weight, and body composition

<p>Abstract</p> <p>Background</p> <p>The family environment offers several opportunities through which to improve adolescents' weight and weight-related behaviors. This study aims to examine the cross-sectional relationships between multiple factors in the family environment and physical activity (PA), television use (TV), soft drink intake, fruit and vegetable (FV) intake, body mass index (BMI), and body composition among a sample of sociodemographically-diverse adolescent girls.</p> <p>Methods</p> <p>Subjects included girls (mean age = 15.7), 71% of whom identified as a racial/ethnic minority, and one of their parents (dyad n = 253). Parents completed surveys assessing factors in the family environment including familial support for adolescents' PA, healthful dietary intake, and limiting TV use; parental modeling of behavior; and resources in the home such as availability of healthful food. Girls' PA and TV use were measured by 3-Day Physical Activity Recall (3DPAR) and dietary intake by survey measures. BMI was measured by study staff, and body fat by dual-energy X-ray absorptiometry (DXA). Hierarchical linear regression models tested individual and mutually-adjusted relationships between family environment factors and girls' outcomes.</p> <p>Results</p> <p>In the individual models, positive associations were observed between family support for PA and girls' total PA (p = .011) and moderate-to-vigorous PA (p=.016), home food availability and girls' soft drink (p < .001) and FV (p < .001) intake, and family meal frequency and girls' FV intake (p = .023). Across the individual and mutually-adjusted models, parental modeling of PA, TV, and soft drink and FV intake was consistently associated with girls' behavior.</p> <p>Conclusions</p> <p>Helping parents improve their physical activity and dietary intake, as well as reduce time watching television, may be an effective way to promote healthful behaviors and weight among adolescent girls.</p

Identification of elongated cilia and chiral malformation in TMEM67 mutant brains

poster abstractTransmembrane protein 67 (TMEM67) is encoded by one of four syndromic encephalocele genes. In humans a mutation in TMEM67 causes Meckel Gruber Syndrome, type 3 (MKS3) which is characterized by severe encephalocele and cystic kidneys and is usually fatal in the neonatal period. MKS3 is one of a spectrum of diseases known as ciliopathies because the proteins responsible for the disease are found in cells with the primary cilia. Primary cilia are a single, hair-like organelle that is found on the apical membrane of polarized cells and is thought to be involved in formation of left-right asymmetry during development as well as mechano- and chemo-reception. Here we characterize previously unreported details of cerebral phenotype in the Wistar polycystic kidney (Wpk) rats with a TMEM67 mutation. In choroid plexus (CP) epithelia of wild type animals, TMEM67 localizes to the plasma membrane and to a region close to the basal side of CP primary cilia. In a choroid plexus cell line that forms an epithelial sheet, the TMEM67 is found intracellularly but also localizes to the junctional complexes as evidenced by β catenin co-localization. Absence of normal TMEM67 leads to elongation of primary cilia in the ependymal cells lining the cerebral ventricles of the TMEM67-/- animals indicating that this protein is involved in the regulation of cilia length. Reduced aqueduct, bilateral dilatation with fusion of lateral ventricles, swelling of the hippocampus, and altered hindbrain histoarchitecture are noted in the TMEM67-/- rats. In the heterozygous animals mild asymmetric ventriculomegaly primarily on the left side is observed during early postnatal periods and continues into adulthood. These results suggest that TMEM67 is required for cilia length control and normal development of cerebral midline that maintains the symmetry of the left and right hemispheres. The Wpk rat model, orthologous to human MKS3, provides a unique model in which to study the development of both severe (TMEM67-/-) and mild (TMEM67+/-) hydrocephalus and other developmental abnormalities that are commonly found in human patients with ciliopathies

On strongly chordal graphs that are not leaf powers

A common task in phylogenetics is to find an evolutionary tree representing proximity relationships between species. This motivates the notion of leaf powers: a graph G = (V, E) is a leaf power if there exist a tree T on leafset V and a threshold k such that uv is an edge if and only if the distance between u and v in T is at most k. Characterizing leaf powers is a challenging open problem, along with determining the complexity of their recognition. This is in part due to the fact that few graphs are known to not be leaf powers, as such graphs are difficult to construct. Recently, Nevries and Rosenke asked if leaf powers could be characterized by strong chordality and a finite set of forbidden subgraphs. In this paper, we provide a negative answer to this question, by exhibiting an infinite family \G of (minimal) strongly chordal graphs that are not leaf powers. During the process, we establish a connection between leaf powers, alternating cycles and quartet compatibility. We also show that deciding if a chordal graph is \G-free is NP-complete, which may provide insight on the complexity of the leaf power recognition problem