Political Competitiveness

Political competitiveness – which many interpret as the degree of democracy – can be modeled as a monopolistic competition. All regimes are constrained by the threat of "entry," and thereby seek some combination of popular support and political entry barriers. This simple model predicts that many public policies are unrelated to political competitiveness, and that even unchallenged nondemocratic regimes should tax far short of their Laffer curve maximum. Economic sanctions, odious debt repudiation, and other policies designed to punish dictators can have the unintended consequences of increasing oppression and discouraging competition. Since entry barriers are a form of increasing returns, democratic countries (defined according to low entry barriers) are more likely to subdivide and nondemocratic countries are more likely to merge. These and other predictions are consistent with previous empirical findings on comparative public finance, election contests, international conflict, the size of nations, and the Lipset hypothesis. As in the private sector, the number of competitors is not necessarily a good indicator of public sector competitiveness.

Frontostriatal Maturation Predicts Cognitive Control Failure to Appetitive Cues in Adolescents

Adolescent risk-taking is a public health issue that increases the odds of poor lifetime outcomes. One factor thought to influence adolescents' propensity for risk-taking is an enhanced sensitivity to appetitive cues, relative to an immature capacity to exert sufficient cognitive control. We tested this hypothesis by characterizing interactions among ventral striatal, dorsal striatal, and prefrontal cortical regions with varying appetitive load using fMRI scanning. Child, teen, and adult participants performed a go/no-go task with appetitive (happy faces) and neutral cues (calm faces). Impulse control to neutral cues showed linear improvement with age, whereas teens showed a nonlinear reduction in impulse control to appetitive cues. This performance decrement in teens was paralleled by enhanced activity in the ventral striatum. Prefrontal cortical recruitment correlated with overall accuracy and showed a linear response with age for no-go versus go trials. Connectivity analyses identified a ventral frontostriatal circuit including the inferior frontal gyrus and dorsal striatum during no-go versus go trials. Examining recruitment developmentally showed that teens had greater between-subject ventral-dorsal striatal coactivation relative to children and adults for happy no-go versus go trials. These findings implicate exaggerated ventral striatal representation of appetitive cues in adolescents relative to an intermediary cognitive control response. Connectivity and coactivity data suggest these systems communicate at the level of the dorsal striatum differentially across development. Biased responding in this system is one possible mechanism underlying heightened risk-taking during adolescence

When Apps Pollute: Regulating Transportation Network Companies to Maximize Environmental Benefits

Ridesharing h as long been touted as a means to reduce the pollution and congestion caused by personal vehicles, but in practice has been relatively unpopular among Americans. That outlook may be changing, however, thanks to new Transportation Network Companies (TNCs) that toe the line between ridesharing and for-hire passenger transportation services, such as taxis and limousines. UberX, Lyft, Sidecar, and other similar services have rapidly spread to cities throughout the United States, attracting the attention of investors and ire of incumbent transportation providers. Legal commentary has thus far focused on proposed regulations\u27 implications for liability, public safety, and fairness, but this Comment seeks to broaden the conversation to assess their potential environmental implications. By scaling to a degree that ridesharing has been unable to do, TNCs may precipitate a shift away from personal vehicle ownership in urban areas; conversely, they may out-compete and threaten the viability of more sustainable transportation options. Through the lens of rulemakings in the California and Colorado Public Utilities Commissions and an ordinance implemented by the Seattle City Council, this Comment assesses which regulatory strategies and provisions are most likely to capture TNCs\u27 potential benefits while mitigating environmental harms

Theoretical Analysis of Information Watermarking in Wavelet-Based Video Compression

Embedding audio bits into images for transmission of video data alleviates the synchronization problem common in video transmission techniques. We continue work combining audio or other information bits and images into one file using digital watermarking techniques to correct the synchronization problem. The system compresses the file by using wavelet image coefficients and implementing bit plane coding. Our research encompasses incorporating five free variables into the watermark/compression technique. These variables are watermark robustness, number of coding iterations, number of image coefficients, number of watermarked information bits, and number of watermarked error correcting bits. By altering these variables, four measurements of the output change. The measurements are the information bit error rate, the image quality, the bit rate, and the amount of watermarked data. We theoretically demonstrate how the variables impact these measurements. Experimental results on real video data support our theoretical findings. By analyzing each video frame, an automated system is able to choose optimal values of the five variables to meet 5 specified measurement constraints

Comparative Genomics of 9 Novel Paenibacillus Larvae Bacteriophages

American Foulbrood Disease, caused by the bacterium Paenibacillus larvae, is one of the most destructive diseases of the honeybee, Apis mellifera. Our group recently published the sequences of 9 new phages with the ability to infect and lyse P. larvae. Here, we characterize the genomes of these P. larvae phages, compare them to each other and to other sequenced P. larvae phages, and putatively identify protein function. The phage genomes are 38–45 kb in size and contain 68–86 genes, most of which appear to be unique to P. larvae phages. We classify P. larvae phages into 2 main clusters and one singleton based on nucleotide sequence identity. Three of the new phages show sequence similarity to other sequenced P. larvae phages, while the remaining 6 do not. We identified functions for roughly half of the P. larvae phage proteins, including structural, assembly, host lysis, DNA replication/metabolism, regulatory, and host-related functions. Structural and assembly proteins are highly conserved among our phages and are located at the start of the genome. DNA replication/metabolism, regulatory, and host-related proteins are located in the middle and end of the genome, and are not conserved, with many of these genes found in some of our phages but not others. All nine phages code for a conserved N-acetylmuramoyl-L-alanine amidase. Comparative analysis showed the phages use the “cohesive ends with 30 overhang” DNA packaging strategy. This work is the first in-depth study of P. larvae phage genomics, and serves as a marker for future work in this area

Gz, a guanine nucleotide-binding protein with unique biochemical properties

Cloning of a complementary DNA (cDNA) for Gz alpha, a newly appreciated member of the family of guanine nucleotide-binding regulatory proteins (G proteins), has allowed preparation of specific antisera to identify the protein in tissues and to assay it during purification from bovine brain. Additionally, expression of the cDNA in Escherichia coli has resulted in the production and purification of the recombinant protein. Purification of Gz from bovine brain is tedious, and only small quantities of protein have been obtained. The protein copurifies with the beta gamma subunit complex common to other G proteins; another 26- kDa GTP-binding protein is also present in these preparations. The purified protein could not serve as a substrate for NAD-dependent ADP- ribosylation catalyzed by either pertussis toxin or cholera toxin. Purification of recombinant Gz alpha (rGz alpha) from E. coli is simple, and quantities of homogeneous protein sufficient for biochemical analysis are obtained. Purified rGz alpha has several properties that distinguish it from other G protein alpha subunit polypeptides. These include a very slow rate of guanine nucleotide exchange (k = 0.02 min^-1), which is reduced greater than 20-fold in the presence of mM concentrations of Mg2+. In addition, the rate of the intrinsic GTPase activity of Gz alpha is extremely slow. The hydrolysis rate (kcat) for rGz alpha at 30 degrees C is 0.05 min^-1, or 200-fold slower than that determined for other G protein alpha subunits. rGz alpha can interact with bovine brain beta gamma but does not serve as a substrate for ADP-ribosylation catalyzed by either pertussis toxin or cholera toxin. These studies suggest that Gz may play a role in signal transduction pathways that are mechanistically distinct from those controlled by the other members of the G protein family

Beginning Teachers’ Perceptions of Preparedness to Differentiate Instruction for Diverse Learners

A two-phase, sequential mixed-methods design was used to assess perceptions of Preparedness (28 items, alpha = .96) to differentiate instruction for N = 36 graduates from one MAT teacher preparation program. Data were analyzed using descriptive statistics, one-way ANOVA and t-test procedures. A focus group with N = 10 purposively selected 2010 graduates and interviews with N = 2 graduates each from the 2008 and 2009 classes, and N = 2 faculty were conducted. The following areas presented challenges to teachers when attempting differentiation: pre-existing ideas of how to teach which contradict differentiation, misinformation regarding differentiation, and classroom management skills. This resulted in the unintentional implementation of surface-level differentiation, rather than deep-structure differentiation (Brighton, Hertberg, Moon, Tomlinson, & Callahan, 2005)

Perceived Efficacy of Beginning Teachers to Differentiate Instruction

A two-phase, sequential mixed-methods design was used to assess perceptions of teacher efficacy (10 item survey, alpha = .90) to differentiate instruction for N = 36 graduates from one MAT teacher preparation program. Research questions addressed levels of self-efficacy, perceptions of preparedness, teaching tenure, and number of certifications held. Data were analyzed using descriptive statistics, one-way ANOVA and t-test procedures. A focus group with N = 10 purposively selected 2010 graduates and interviews with N = 2 graduates each from the 2008 and 2009 classes, and N = 2 faculty were conducted. No significant relationships were found for tenure and number of certifications. A relationship was found between levels of self-efficacy and feelings of preparedness (r = .91, r2 = .81, p \u3c .001). Pre-existing ideas of how to teach which contradict differentiation, misinformation regarding differentiation, and classroom management skills presented challenges which resulted in the unintentional implementation of surface-level differentiation, rather than deep-structure differentiation (Brighton, Hertberg, Moon, Tomlinson, & Callahan, 2005)