Perturbation theory for the two-dimensional abelian Higgs model in the unitary gauge

In the unitary gauge the unphysical degrees of freedom of spontaneously broken gauge theories are eliminated. The Feynman rules are simpler than in other gauges, but it is non-renormalizable by the rules of power counting. On the other hand, it is formally equal to the limit $\xi \to 0$ of the renormalizable R$_{\xi}$-gauge. We consider perturbation theory to one-loop order in the R$_{\xi}$-gauge and in the unitary gauge for the case of the two-dimensional abelian Higgs model. An apparent conflict between the unitary gauge and the limit $\xi \to 0$ of the R$_{\xi}$-gauge is resolved, and it is demonstrated that results for physical quantities can be obtained in the unitary gauge.Comment: 15 pages, LaTeX2e, uses the feynmf package, formulations correcte

Paternal Parenting Stress during Middle Childhood: The Impact of COVID-19

Background: Parenting stress is the unpleasant psychological reaction to the demands of parenthood, including perceptions of competence at and knowledge of the day-to-day and long-term tasks of parenting (Deater-Deckard 2006). While most research has examined mothers, father parenting stress is also critical to children’s development, predicting increased problem behaviors (Cabrera & Mitchell 2009) and poorer cognitive skills (Harwood, 2017). The COVID-19 pandemic may increase parental stress in multiple ways, as parents are at home more with their children while fulfilling occupational and personal responsibilities. Parents have reported increased stress due to job loss, school closures, and other stressors (van Tilburg et al., 2020), and COVID-19 stressors are associated with higher parental stress in mothers (Brown et al., 2020). This study aimed to examine: 1) how parenting stress in fathers relates to sociodemographics; 2) how COVID-19 may impact parenting stress, relative to sociodemographics. It was hypothesized that 1) fathers in families with less education or income, unmarried, or living in rural areas would report higher parenting stress, and 2) COVID-19 would contribute to parenting stress over and above sociodemographics. Methods: Participants were fathers (n=172) of children ages 6-10, living in the United States, and had at least regular visitation with their child. Fathers were surveyed once through Amazon’s Mechanical Turk between November 2020 through February 2021. The sample was 58% White, 18.6% Black, 7.6% Hispanic, 7.6% Asian American/Pacific Islander, 8.1% All Other Races and Ethnicities, and 97.1% worked full-time. Measures included the Parent-Child Dysfunctional Interaction subscale of the Parenting Stress Index, 4th Edition Short Form (Abidin, 2012), the COVID-19 Impact Scale (Kaufman & Stoddard, 2020), and demographic factors (father age, household income, perceived social class, marital status, education, and urban/rural environment). Results: COVID-19 impact was positively associated with the parenting stress (parent-child dysfunction subscale; r=.50, p\u3c.001). Greater parenting stress was also associated with higher perceived social class (r=.237, p\u3c.001), more education (r=.24, p\u3c.001), and being married (t(155)=-2.81, p=.006). Fathers in urban environments endorsed more parenting stress (t(170)=2.57, p=.011) than those in rural environments. There were no significant associations between father age or household income with parenting stress. Regressions indicated COVID-19 impact was associated with parenting stress (ꞵ=.446, R2=.318, p\u3c.001) over and above the impact of marital status, perceived social class, urban/rural environment, and education level. Blocked regression indicated that COVID-19 impact was associated with parenting stress over and above sociodemographic factors. Block 1 explained 12% of the variance in parenting stress while adding COVID-19 impact to Block 2 explained 31% of the variance in parenting stress. Discussion: COVID-19 and parenting stress were strongly associated with one another. However, contrary to hypotheses, fathers who were married, more educated, identified with higher social classes, or lived in urban environments reported more parenting stress. This may be due to the impact of COVID-19, such that married fathers may have more time with their children, fathers with higher education or perceived social class may be working from home more, and urban areas may have seen more dramatic changes to daily life. Fathers more impacted by COVID-19 may benefit from additional supports or services to reduce demands and parenting stress. Although a single timepoint and single-reporter measurement, findings suggest that interventions designed to reduce COVID-19 related stressors may, in turn, benefit other aspects of family well-being

Anisotropy of the Cosmic Neutrino Background

The cosmic neutrino background (CNB) consists of low-energy relic neutrinos which decoupled from the cosmological fluid at a redshift z ~ 10^{10}. Despite being the second-most abundant particles in the universe, direct observation remains a distant challenge. Based on the measured neutrino mass differences, one species of neutrinos may still be relativistic with a thermal distribution characterized by the temperature T ~ 1.9K. We show that the temperature distribution on the sky is anisotropic, much like the photon background, experiencing Sachs-Wolfe and integrated Sachs-Wolfe effects.Comment: 5 pages, 2 figures / updated references, discussion of earlier wor

PARE: A tool for comparing protein abundance and mRNA expression data

<p>Abstract</p> <p>Background</p> <p>Techniques for measuring protein abundance are rapidly advancing and we are now in a situation where we anticipate many protein abundance data sets will be available in the near future. Since proteins are translated from mRNAs, their expression is expected to be related to their abundance, to some degree.</p> <p>Results</p> <p>We have developed a web tool, called PARE (Protein Abundance and mRNA Expression; <url>http://proteomics.gersteinlab.org</url>), to correlate these two quantities. In addition to globally comparing the quantities of protein and mRNA, PARE allows users to select subsets of proteins for focused study (based on functional categories and complexes). Furthermore, it highlights correlation outliers, which are potentially worth further examination.</p> <p>Conclusion</p> <p>We anticipate PARE will facilitate comparative studies on mRNA and protein abundance by the proteomics community.</p

An efficient pseudomedian filter for tiling microrrays

<p>Abstract</p> <p>Background</p> <p>Tiling microarrays are becoming an essential technology in the functional genomics toolbox. They have been applied to the tasks of novel transcript identification, elucidation of transcription factor binding sites, detection of methylated DNA and several other applications in several model organisms. These experiments are being conducted at increasingly finer resolutions as the microarray technology enjoys increasingly greater feature densities. The increased densities naturally lead to increased data analysis requirements. Specifically, the most widely employed algorithm for tiling array analysis involves smoothing observed signals by computing pseudomedians within sliding windows, a <it>O</it>(<it>n</it>²log<it>n</it>) calculation in each window. This poor time complexity is an issue for tiling array analysis and could prove to be a real bottleneck as tiling microarray experiments become grander in scope and finer in resolution.</p> <p>Results</p> <p>We therefore implemented Monahan's HLQEST algorithm that reduces the runtime complexity for computing the pseudomedian of <it>n </it>numbers to <it>O</it>(<it>n</it>log<it>n</it>) from <it>O</it>(<it>n</it>²log<it>n</it>). For a representative tiling microarray dataset, this modification reduced the smoothing procedure's runtime by nearly 90%. We then leveraged the fact that elements within sliding windows remain largely unchanged in overlapping windows (as one slides across genomic space) to further reduce computation by an additional 43%. This was achieved by the application of skip lists to maintaining a sorted list of values from window to window. This sorted list could be maintained with simple <it>O</it>(log <it>n</it>) inserts and deletes. We illustrate the favorable scaling properties of our algorithms with both time complexity analysis and benchmarking on synthetic datasets.</p> <p>Conclusion</p> <p>Tiling microarray analyses that rely upon a sliding window pseudomedian calculation can require many hours of computation. We have eased this requirement significantly by implementing efficient algorithms that scale well with genomic feature density. This result not only speeds the current standard analyses, but also makes possible ones where many iterations of the filter may be required, such as might be required in a bootstrap or parameter estimation setting. Source code and executables are available at <url>http://tiling.gersteinlab.org/pseudomedian/</url>.</p

Eat Smart. Play Hard™ San Luis Obispo: A Nutrition and Fitness Pilot Program for Young Children and Their Adult Buddies

Eat Smart. Play Hard™. San Luis Obispo!, a multi-component primary prevention program targeting low-income, Hispanic children 6-8 years, focuses on promoting healthy dietary and physical activity behaviors using an innovative child-adult buddy system approach. The child-adult buddies participate in multiple activities to increase their consumption of fruits and vegetables, and level of physical activity and decrease their consumption of sweetened beverages. The results of the pilot program show high program satisfaction and improvements in dietary and physical activity behaviors. Such programs provide an opportunity to establish and promote healthy behaviors among young children and ultimately prevent overweight development

Communications Biophysics

Contains reports on three research projects.United States Air Force (Contract AF19(604)-4112

Toward a universal microarray: prediction of gene expression through nearest-neighbor probe sequence identification

A generic DNA microarray design applicable to any species would greatly benefit comparative genomics. We have addressed the feasibility of such a design by leveraging the great feature densities and relatively unbiased nature of genomic tiling microarrays. Specifically, we first divided each Homo sapiens Refseq-derived gene's spliced nucleotide sequence into all of its possible contiguous 25 nt subsequences. For each of these 25 nt subsequences, we searched a recent human transcript mapping experiment's probe design for the 25 nt probe sequence having the fewest mismatches with the subsequence, but that did not match the subsequence exactly. Signal intensities measured with each gene's nearest-neighbor features were subsequently averaged to predict their gene expression levels in each of the experiment's thirty-three hybridizations. We examined the fidelity of this approach in terms of both sensitivity and specificity for detecting actively transcribed genes, for transcriptional consistency between exons of the same gene, and for reproducibility between tiling array designs. Taken together, our results provide proof-of-principle for probing nucleic acid targets with off-target, nearest-neighbor features