Integrating constructive feedback in personalised e-learning

When using e-learning material some students progress readily, others have difficulties. In a traditional classroom the teacher would identify those with difficulties and direct them to additional resources. This support is not easily available within e-learning. A new approach to providing constructive feedback is developed that will enable an e-learning system to identify areas of weakness and provide guidance on further study. The approach is based on the tagging of learning material with appropriate keywords that indicate the contents. Thus if a student performs poorly on an assessment on topic X, there is a need to suggest further study of X and participation in activities related to X such as forums. As well as supporting the learner this type of constructive feedback can also inform other stakeholders. For example a tutor can monitor the progress of a cohort; an instructional designer can monitor the quality of learning objects in facilitating the appropriate knowledge across many learners

Monte Carlo Methods for Estimating Interfacial Free Energies and Line Tensions

Excess contributions to the free energy due to interfaces occur for many problems encountered in the statistical physics of condensed matter when coexistence between different phases is possible (e.g. wetting phenomena, nucleation, crystal growth, etc.). This article reviews two methods to estimate both interfacial free energies and line tensions by Monte Carlo simulations of simple models, (e.g. the Ising model, a symmetrical binary Lennard-Jones fluid exhibiting a miscibility gap, and a simple Lennard-Jones fluid). One method is based on thermodynamic integration. This method is useful to study flat and inclined interfaces for Ising lattices, allowing also the estimation of line tensions of three-phase contact lines, when the interfaces meet walls (where "surface fields" may act). A generalization to off-lattice systems is described as well. The second method is based on the sampling of the order parameter distribution of the system throughout the two-phase coexistence region of the model. Both the interface free energies of flat interfaces and of (spherical or cylindrical) droplets (or bubbles) can be estimated, including also systems with walls, where sphere-cap shaped wall-attached droplets occur. The curvature-dependence of the interfacial free energy is discussed, and estimates for the line tensions are compared to results from the thermodynamic integration method. Basic limitations of all these methods are critically discussed, and an outlook on other approaches is given

The Cancer Genome Atlas Comprehensive Molecular Characterization of Renal Cell Carcinoma

Renal cell carcinoma(RCC) is not a single disease, but several histologically defined cancers with different genetic drivers, clinical courses, and therapeutic responses. The current study evaluated 843 RCC from the three major histologic subtypes, including 488 clear cell RCC, 274 papillary RCC, and 81 chromophobe RCC. Comprehensive genomic and phenotypic analysis of the RCC subtypes reveals distinctive features of each subtype that provide the foundation for the development of subtype-specific therapeutic and management strategies for patients affected with these cancers. Somatic alteration of BAP1, PBRM1, and PTEN and altered metabolic pathways correlated with subtype-specific decreased survival, while CDKN2A alteration, increased DNA hypermethylation, and increases in the immune-related Th2 gene expression signature correlated with decreased survival within all major histologic subtypes. CIMP-RCC demonstrated an increased immune signature, and a uniform and distinct metabolic expression pattern identified a subset of metabolically divergent (MD) ChRCC that associated with extremely poor survival

The Extended Chandra Deep Field-South Survey: Chandra Point-Source Catalogs

We present Chandra point‐source catalogs for the Extended Chandra Deep Field–South (E‐CDF‐S) survey. The E‐CDF‐S consists of four contiguous 250 ks Chandra observations covering an approximately square region of total solid angle ≈0.3 deg2, which flank the existing ≈1 Ms Chandra Deep Field–South (CDF‐S). The survey reaches sensitivity limits of ≈ and ≈ ergs cm−2 s−1 for the 0.5–2.0 and 2–8 keV bands, respectively. We detect 762 distinct X‐ray point sources within the E‐CDF‐S exposure; 589 of these sources are new (i.e., not previously detected in the ≈1 Ms CDF‐S). This brings the total number of X‐ray point sources detected in the E‐CDF‐S region to 915 (via the E‐CDF‐S and ≈1 Ms CDF‐S observations). Source positions are determined using matched‐filter and centroiding techniques; the median positional uncertainty is ≈035. The basic X‐ray and optical properties of these sources indicate a variety of source types, although absorbed active galactic nuclei (AGNs) seem to dominate. In addition to our main Chandra catalog, we constructed a supplementary source catalog containing 33 lower significance X‐ray point sources that have bright optical counterparts (R < 23). These sources generally have X‐ray–to–optical flux ratios expected for normal and starburst galaxies, which lack a strong AGN component. We present basic number‐count results for our main Chandra catalog and find good agreement with the ≈1 Ms CDF‐S for sources with 0.5–2.0 and 2–8 keV fluxes greater than and ergs cm−2 s−1, respectively. Furthermore, three extended sources are detected in the 0.5–2.0 keV band, which are found to be likely associated with galaxy groups or poor clusters at ; these have typical rest‐frame 0.5–2.0 keV luminosities of ergs s−1

The Extended Chandra Deep Field-South Survey: Optical Spectroscopy of Faint X-ray Sources with the VLT and Keck

We present the results of a program to acquire high-quality optical spectra of X-ray sources detected in the E-CDF-S and its central area. New spectroscopic redshifts are measured for 283 counterparts to Chandra sources with deep exposures (t~2-9 hr per pointing) using multi-slit facilities on both the VLT and Keck thus bringing the total number of spectroscopically-identified X-ray sources to over 500 in this survey field. We provide a comprehensive catalog of X-ray sources detected in the E-CDF-S including the optical and near-infrared counterparts, and redshifts (both spectroscopic and photometric) that incorporate published spectroscopic catalogs thus resulting in a final sample with a high fraction (80%) of X-ray sources having secure identifications. We demonstrate the remarkable coverage of the Lx-z plane now accessible from our data while emphasizing the detection of AGNs that contribute to the faint end of the luminosity function at 1.5<z<3. Our redshift catalog includes 17 type 2 QSOs that significantly increases such samples (2x). With our deepest VIMOS observation, we identify "elusive" optically-faint galaxies (R~25) at z~2-3 based upon the detection of interstellar absorption lines; we highlight one such case, an absorption-line galaxy at z=3.208 having no obvious signs of an AGN in its optical spectrum. In addition, we determine distances to eight galaxy groups with extended X-ray emission. Finally, we measure the physical extent of known large-scale structures (z~0.7) evident in the CDF-S. While a thick sheet (radial size of 67.7 Mpc) at z~0.67 extends over the full field, the z~0.73 structure is thin (18.8 Mpc) and filamentary as traced by both AGNs and galaxy groups. In the appendix, we provide spectroscopic redshifts for 49 counterparts to fainter X-ray sources detected only in the 1 and 2 Ms catalogs, and 48 VLA radio sources not detected in X-rays.Comment: Accepted for publication in ApJS; 20 pages; 12 figures; High-level data products including redshift catalogs are available from http://member.ipmu.jp/john.silverman/CDFS.htm

U.S. Prison Seminaries: Structural Charity, Religious Establishment, and Neoliberal Corrections

Using archival and site-based research, this article explores operational practices at six U.S. prison seminary programs regarding concepts of religious establishment. Further highlighted is a shift toward faith-based volunteerism as a “structural charity” in correctional budgeting. While religious programs offer powerfully transformative access to social capital for many inmates, the recent insertion of Christian “seminaries” into U.S. prisons arguably fosters religious establishment in four key areas: a lack of state neutrality toward religion, excessive state entanglement with religious service providers, inadequate solicitation of alternative programming, and a de facto measure of coercion in delivery of services