Exploring Relations Between BCG and Cluster Properties in the SPectroscopic IDentification of eROSITA Sources Survey from 0.05<z<0.30.05 < z < 0.3

We present a sample of 329 low to intermediate redshift ($0.05 < z < 0.3$) brightest cluster galaxies (BCGs) in X-ray selected clusters from the SPectroscopic IDentification of eRosita Sources (SPIDERS) survey, a spectroscopic survey within Sloan Digital Sky Survey-IV (SDSS-IV). We define our BCGs by simultaneous consideration of legacy X-ray data from ROSAT, maximum likelihood outputs from an optical cluster-finder algorithm and visual inspection. Using SDSS imaging data, we fit S\'ersic profiles to our BCGs in three bands (\textit{g}, \textit{r}, \textit{i}) with \textsc{SIGMA}, a \textsc{GALFIT}-based software wrapper. We examine the reliability of our fits by running our pipeline on ${\sim}10^{4}$ psf-convolved model profiles injected into 8 random cluster fields, we then use the results of this analysis to create a robust subsample of 198 BCGs. We outline three cluster properties of interest: overall cluster X-ray luminosity ($L_{X}$), cluster richness as estimated by \textsc{redMaPPer} ($\lambda$) and cluster halo mass ($M_{200}$), which is estimated via velocity dispersion. In general, there are significant correlations with BCG stellar mass between all three environmental properties, but no significant trends arise with either S\'ersic index or effective radius. There is no major environmental dependence on the strength of the relation between effective radius and BCG stellar mass. Stellar mass therefore arises as the most important factor governing BCG morphology. Our results indicate that our sample consists of a large number of relaxed, mature clusters containing broadly homogeneous BCGs up to $z \sim 0.3$, suggesting that there is little evidence for much ongoing structural evolution for BCGs in these systems

Reproducible kk-means clustering in galaxy feature data from the GAMA survey

A fundamental bimodality of galaxies in the local Universe is apparent in many of the features used to describe them. Multiple sub-populations exist within this framework, each representing galaxies following distinct evolutionary pathways. Accurately identifying and characterising these sub-populations requires that a large number of galaxy features be analysed simultaneously. Future galaxy surveys such as LSST and Euclid will yield data volumes for which traditional approaches to galaxy classification will become unfeasible. To address this, we apply a robust $k$-means unsupervised clustering method to feature data derived from a sample of 7338 local-Universe galaxies selected from the Galaxy And Mass Assembly (GAMA) survey. This allows us to partition our sample into $k$ clusters without the need for training on pre-labelled data, facilitating a full census of our high dimensionality feature space and guarding against stochastic effects. We find that the local galaxy population natively splits into $2$, $3$, $5$ and a maximum of $6$ sub-populations, with each corresponding to a distinct ongoing evolutionary mechanism. Notably, the impact of the local environment appears strongly linked with the evolution of low-mass ($M_{*} < 10^{10}$ M$_{\odot}$) galaxies, with more massive systems appearing to evolve more passively from the blue cloud onto the red sequence. With a typical run time of $\sim3$ minutes per value of $k$ for our galaxy sample, we show how $k$-means unsupervised clustering is an ideal tool for future analysis of large extragalactic datasets, being scalable, adaptable, and providing crucial insight into the fundamental properties of the local galaxy population

General Form of the Color Potential Produced by Color Charges of the Quark

Constant electric charge $e$ satisfies the continuity equation $\partial_\mu j^{\mu}(x)= 0$ where $j^\mu(x)$ is the current density of the electron. However, the Yang-Mills color current density $j^{\mu a}(x)$ of the quark satisfies the equation $D_\mu[A] j^{\mu a}(x)= 0$ which is not a continuity equation ($\partial_\mu j^{\mu a}(x)\neq 0$) which implies that a color charge $q^a(t)$ of the quark is not constant but it is time dependent where $a=1,2,...8$ are color indices. In this paper we derive general form of color potential produced by color charges of the quark. We find that the general form of the color potential produced by the color charges of the quark at rest is given by \Phi^a(x) =A_0^a(t,{\bf x}) =\frac{q^b(t-\frac{r}{c})}{r}\[\frac{{\rm exp}[g\int dr \frac{Q(t-\frac{r}{c})}{r}] -1}{g \int dr \frac{Q(t-\frac{r}{c})}{r}}\]_{ab} where $dr$ integration is an indefinite integration, ~~ $Q_{ab}(\tau_0)=f^{abd}q^d(\tau_0)$, ~~$r=|{\vec x}-{\vec X}(\tau_0)|$, ~~$\tau_0=t-\frac{r}{c}$ is the retarded time, ~~$c$ is the speed of light, ~~${\vec X}(\tau_0)$ is the position of the quark at the retarded time and the repeated color indices $b,d$(=1,2,...8) are summed. For constant color charge $q^a$ we reproduce the Coulomb-like potential $\Phi^a(x)=\frac{q^a}{r}$ which is consistent with the Maxwell theory where constant electric charge $e$ produces the Coulomb potential $\Phi(x)=\frac{e}{r}$.Comment: Final version, two more sections added, 45 pages latex, accepted for publication in JHE

Trypanocidal and leishmanicidal activity of six limonoids

Six limonoids [kotschyienone A and B (1, 2), 7-deacetylgedunin (3), 7-deacetyl-7-oxogedunin (4), andirobin (5) and methyl angolensate (6)] were investigated for their trypanocidal and leishmanicidal activities using bloodstream forms of Trypanosoma brucei and promastigotes of Leishmania major. Whereas all compounds showed anti-trypanosomal activity, only compounds 1–4 displayed anti-leishmanial activity. The 50% growth inhibition (GI 50) values for the trypanocidal and leishmanicidal activity of the compounds ranged between 2.5 and 14.9 μM. Kotschyienone A (1) was found to be the most active compound with a minimal inhibition concentration (MIC) value of 10 μM and GI 50 values between 2.5 and 2.9 μM. Only compounds 1 and 3 showed moderate cytotoxicity against HL-60 cells with MIC and GI 50 values of 100 μM and 31.5–46.2 μM, respectively. Compound 1 was also found to show activity against intracellular amastigotes of L. major with a GI 50 value of 1.5 μM. The results suggest that limonoids have potential as drug candidates for the development of new treatments against trypanosomiasis and leishmaniasis

Identification of capacity development indicators for faculty development programs: A nominal group technique study.

BackgroundAlthough there have been many research studies of the effectiveness of faculty development in health profession education, the contribution of these programs to organizational development through capacity development has not been studied. Further understanding of capacity development requires appropriate indicators and no previous indicators for faculty development of health profession educators were identified. The aim of the study was to identify indicators of capacity development in the context of faculty development programs at Tehran University of medical sciences (TUMS).MethodsA nominal group technique session was conducted with key informants from faculty development program providers to generate and prioritize a list of capacity development indicators.ResultsA list of 26 indicators was generated and five categories were identified: Development and innovation in teaching and learning process, Development and innovation in communication and collaboration at different levels, Development and sustaining faculty development programs, Development of educational leadership and management, Development in scholarship.ConclusionsCapacity development for faculty development interventions of health profession educators is a process of engagement within a wider system, including individual and collective action, and involves the socialization of the teachers into suitable roles through professional identity development and participation within the wider system

Structural and functional relationships in the virulence-associated cathepsin L proteases of the parasitic liver fluke, Fasciola hepatica

The helminth parasite Fasciola hepatica secretes cysteine proteases to facilitate tissue invasion, migration, and development within the mammalian host. The major proteases cathepsin L1 (FheCL1) and cathepsin L2 (FheCL2) were recombinantly produced and biochemically characterized. By using site-directed mutagenesis, we show that residues at position 67 and 205, which lie within the S2 pocket of the active site, are critical in determining the substrate and inhibitor specificity. FheCL1 exhibits a broader specificity and a higher substrate turnover rate compared with FheCL2. However, FheCL2 can efficiently cleave substrates with a Pro in the P2 position and degrade collagen within the triple helices at physiological pH, an activity that among cysteine proteases has only been reported forhuman cathepsin K. The 1.4-Å three-dimensional structure of the FheCL1 was determined by x-ray crystallography, and the three-dimensional structure of FheCL2 was constructed via homology-based modeling. Analysis and comparison of these structures and our biochemical data with those of human cathepsins L and Kprovided an interpretation of the substrate-recognition mechanisms of these major parasite proteases. Furthermore, our studies suggest that a configuration involving residue 67 and the "gatekeeper" residues 157 and 158 situated at the entrance of the active site pocket create a topology that endows FheCL2 with its unusual collagenolytic activity. The emergence of a specialized collagenolytic function in Fasciola likely contributes to the success of this tissue-invasive parasite. © 2008 by The American Society for Biochemistry and Molecular Biology, Inc

Engaging with community researchers for exposure science: lessons learned from a pesticide biomonitoring study

A major challenge in biomonitoring studies with members of the general public is ensuring their continued involvement throughout the necessary length of the research. The paper presents evidence on the use of community researchers, recruited from local study areas, as a mechanism for ensuring effective recruitment and retention of farmer and resident participants for a pesticides biomonitoring study. The evidence presented suggests that community researchers' abilities to build and sustain trusting relationships with participants enhanced the rigour of the study as a result of their on-the-ground responsiveness and flexibility resulting in data collection beyond targets expected

Roy-Steiner equations for pion-nucleon scattering

Starting from hyperbolic dispersion relations, we derive a closed system of Roy-Steiner equations for pion-nucleon scattering that respects analyticity, unitarity, and crossing symmetry. We work out analytically all kernel functions and unitarity relations required for the lowest partial waves. In order to suppress the dependence on the high-energy regime we also consider once- and twice-subtracted versions of the equations, where we identify the subtraction constants with subthreshold parameters. Assuming Mandelstam analyticity we determine the maximal range of validity of these equations. As a first step towards the solution of the full system we cast the equations for the $\pi\pi\to\bar NN$ partial waves into the form of a Muskhelishvili-Omn\`es problem with finite matching point, which we solve numerically in the single-channel approximation. We investigate in detail the role of individual contributions to our solutions and discuss some consequences for the spectral functions of the nucleon electromagnetic form factors.Comment: 106 pages, 18 figures; version published in JHE

Sensitivity of Chaos Measures in Detecting Stress in the Focusing Control Mechanism of the Short-Sighted Eye

yesWhen fixating on a stationary object, the power of the eye’s lens fluctuates. Studies have suggested that changes in these so-called microfluctuations in accommodation may be a factor in the onset and progression of short-sightedness. Like many physiological signals, the fluctuations in the power of the lens exhibit chaotic behaviour. A breakdown or reduction in chaos in physiological systems indicates stress to the system or pathology. The purpose of this study was to determine whether the chaos in fluctuations of the power of the lens changes with refractive error, i.e. how short-sighted a subject is, and/or accommodative demand, i.e. the effective distance of the object that is being viewed. Six emmetropes (EMMs, non-short-sighted), six early-onset myopes (EOMs, onset of short-sightedness before the age of 15), and six late-onset myopes (LOMs, onset of short-sightedness after the age of 15) took part in the study. Accommodative microfluctuations were measured at 22 Hz using an SRW-5000 autorefractor at accommodative demands of 1 D (dioptres), 2 D, and 3 D. Chaos theory analysis was used to determine the embedding lag, embedding dimension, limit of predictability, and Lyapunov exponent. Topological transitivity was also tested for. For comparison, the power spectrum and standard deviation were calculated for each time record. The EMMs had a statistically significant higher Lyapunov exponent than the LOMs ( 0.64±0.330.64±0.33 vs. 0.39±0.20 D/s0.39±0.20 D/s ) and a lower embedding dimension than the LOMs ( 3.28±0.463.28±0.46 vs. 3.67±0.493.67±0.49 ). There was insufficient evidence (non-significant p value) of a difference between EOMs and EMMs or EOMs and LOMs. The majority of time records were topologically transitive. There was insufficient evidence of accommodative demand having an effect. Power spectrum analysis and assessment of the standard deviation of the fluctuations failed to discern differences based on refractive error. Chaos differences in accommodation microfluctuations indicate that the control system for LOMs is under stress in comparison to EMMs. Chaos theory analysis is a more sensitive marker of changes in accommodation microfluctuations than traditional analysis methods

A comprehensive 1000 Genomes-based genome-wide association meta-analysis of coronary artery disease

Existing knowledge of genetic variants affecting risk of coronary artery disease (CAD) is largely based on genome-wide association studies (GWAS) analysis of common SNPs. Leveraging phased haplotypes from the 1000 Genomes Project, we report a GWAS meta-analysis of 185 thousand CAD cases and controls, interrogating 6.7 million common (MAF>0.05) as well as 2.7 million low frequency (0.005<MAF<0.05) variants. In addition to confirmation of most known CAD loci, we identified 10 novel loci, eight additive and two recessive, that contain candidate genes that newly implicate biological processes in vessel walls. We observed intra-locus allelic heterogeneity but little evidence of low frequency variants with larger effects and no evidence of synthetic association. Our analysis provides a comprehensive survey of the fine genetic architecture of CAD showing that genetic susceptibility to this common disease is largely determined by common SNPs of small effect siz