An Interactive Java Statistical Image Segmentation System: GemIdent

Supervised learning can be used to segment/identify regions of interest in images using both color and morphological information. A novel object identification algorithm was developed in Java to locate immune and cancer cells in images of immunohistochemically-stained lymph node tissue from a recent study published by Kohrt et al. (2005). The algorithms are also showing promise in other domains. The success of the method depends heavily on the use of color, the relative homogeneity of object appearance and on interactivity. As is often the case in segmentation, an algorithm specifically tailored to the application works better than using broader methods that work passably well on any problem. Our main innovation is the interactive feature extraction from color images. We also enable the user to improve the classification with an interactive visualization system. This is then coupled with the statistical learning algorithms and intensive feedback from the user over many classification-correction iterations, resulting in a highly accurate and user-friendly solution. The system ultimately provides the locations of every cell recognized in the entire tissue in a text file tailored to be easily imported into R (Ihaka and Gentleman 1996; R Development Core Team 2009) for further statistical analyses. This data is invaluable in the study of spatial and multidimensional relationships between cell populations and tumor structure. This system is available at http://www.GemIdent.com together with three demonstration videos and a manual. The code is now open-sourced and available on github at: https://github.com/kapelner/GemIden

USE OF CHAMBERLAIN FIXED EFFECTS APPROACH TO ESTIMATE WILLINGNESS-TO-PAY FOR LITTLE TENNESSEE RIVER BASIN MANAGEMENT ALTERNATIVES

The paper discusses an application of Chamberlain's fixed effects model to contingent valuation method survey data obtained for eight management alternatives for the Little Tennessee River basin. The advantages of using this approach versus cross-sectional logit, pooled logit, and cross-sectional logit with lags are discussed and a technique to obtain willingness-to-pay estimates from estimated coefficients is offered. Drawbacks of using Chamberlain's fixed effects model, difficulties encountered, and directions for further research are presented.Environmental Economics and Policy,

Understanding the Cultural-Linguistic Divide in American Classrooms: Language Learning Strategies for a Diverse Student Population

This article addresses critical factors that impact learning for a growing population of students in American classrooms, the English Language Learner (ELL). Even in the smallest school districts, it is common for teachers to have one or more students with limited or no command of the English language in their classrooms. Many students in schools with specialized ELL programs spend the majority of their day in regular classrooms trying to fit in with their peers as they struggle to learn a new language. This article focuses on the five stages of language acquisition and proficiency along with corresponding research-based strategies teachers can use at each stage. Elements of an effective language program described in this article are based on an asset model of instruction where students’ differences are valued, respected, and utilized. When cultural-linguistic differences are used as assets rather than problems, all students, native and non-native English speakers, benefit

The effects of transcranial direct current stimulation on within- and cross-paradigm transfer following multi-session backward recall training.

Transcranial direct current stimulation (tDCS) has been shown to enhance the efficacy and generalisation of working memory (WM) training, but there has been little systematic investigation into how coupling task-specific WM training with stimulation impacts more specifically on transfer to untrained tasks. This randomised controlled trial investigated the boundary conditions to transfer by testing firstly whether the benefits of training on backward digit recall (BDR) extend to untrained backward recall tasks and n-back tasks with different materials, and secondly which, if any, form of transfer is enhanced by tDCS. Forty-eight participants were allocated to one of three conditions: BDR training with anodal (10 min, 1 mA) or sham tDCS, or visual search training with sham tDCS, applied over the left dorsolateral prefrontal cortex. Transfer was assessed on within- (backward recall with digits, letters, and spatial locations) and cross-paradigm (n-back with digits and letters) transfer tests following three sessions of training and stimulation. On-task training gains were found, with transfer to other backward span but not n-back tasks. There was little evidence that tDCS enhanced on-task training or transfer. These findings indicate that training enhances paradigm-specific processes within WM, but that tDCS does not enhance these gains

Natural variation of HIV-1 group M integrase: Implications for a new class of antiretroviral inhibitors

HIV-1 integrase is the third enzymatic target of antiretroviral (ARV) therapy. However, few data have been published on the distribution of naturally occurring amino acid variation in this enzyme. We therefore characterized the distribution of integrase variants among more than 1,800 published group M HIV-1 isolates from more than 1,500 integrase inhibitor (INI)-naïve individuals. Polymorphism rates equal or above 0.5% were found for 34% of the central core domain positions, 42% of the C-terminal domain positions, and 50% of the N-terminal domain positions. Among 727 ARV-naïve individuals in whom the complete pol gene was sequenced, integrase displayed significantly decreased inter- and intra-subtype diversity and a lower Shannon's entropy than protease or RT. All primary INI-resistance mutations with the exception of E157Q – which was present in 1.1% of sequences – were nonpolymorphic. Several accessory INI-resistance mutations including L74M, T97A, V151I, G163R, and S230N were also polymorphic with polymorphism rates ranging between 0.5% to 2.0%