Thermodynamics and renormalized quasi-particles in the vicinity of the dilute Bose gas quantum critical point in two dimensions

We use the functional renormalization group (FRG) to derive analytical expressions for thermodynamic observables (density, pressure, entropy, and compressibility) as well as for single-particle properties (wavefunction renormalization and effective mass) of interacting bosons in two dimensions as a function of temperature $T$ and chemical potential $\mu$. We focus on the quantum disordered and the quantum critical regime close to the dilute Bose gas quantum critical point. Our approach is based on a truncated vertex expansion of the hierarchy of FRG flow equations and the decoupling of the two-body contact interaction in the particle-particle channel using a suitable Hubbard-Stratonovich transformation. Our analytic FRG results extend previous analytical renormalization group calculations for thermodynamic observables at $\mu =0$ to finite values of $\mu$. To confirm the validity of our FRG approach, we have also performed quantum Monte Carlo simulations to obtain the magnetization, the susceptibility, and the correlation length of the two-dimensional spin-$1/2$ quantum $XY$ model with coupling $J$ in a regime where its quantum critical behavior is controlled by the dilute Bose gas quantum critical point. We find that our analytical results describe the Monte Carlo data for $\mu \leq 0$ rather accurately up to relatively high temperatures $T \lesssim 0.1 J$.Comment: 18 pages, 13 figure

Extracting the Single-Particle Gap in Carbon Nanotubes with Lattice Quantum Monte Carlo

We show how lattice Quantum Monte Carlo simulations can be used to calculate electronic properties of carbon nanotubes in the presence of strong electron-electron correlations. We employ the path integral formalism and use methods developed within the lattice QCD community for our numerical work and compare our results to empirical data of the Anti-Ferromagnetic Mott Insulating gap in large diameter tubes.Comment: 8 pages, 5 figures, Lat2017 proceedin

cGMP at the centre of attention: emerging strategies for activating the cardioprotective PKG pathway.

The nitric oxide (NO)-protein kinase G (PKG) pathway has been known for some time to be an important target for cardioprotection against ischaemia/reperfusion injury and heart failure. While many approaches for reducing infarct size in patients have failed in the past, the advent of novel drugs that modulate cGMP and its downstream targets shows very promising results in recent preclinical and clinical studies. Here, we review main aspects of the NO-PKG pathway in light of recent drug development and summarise potential cardioprotective strategies in which cGMP is the main player

Dermatofibrosarcoma Protuberans: Altered Collagen Metabolism in Cell Culture

Dermatofibrosarcoma protuberans is a low-grade malignant tumor that grows invasively but rarely forms metastases. Its origin is still controversial. We characterized the synthesis of collagen in detail in cells which were obtained from dermatofibrosarcoma protuberans tumors by enzymatic tissue disintegration. Similar to fibroblasts, all tumor cell strains produced considerable amounts of collagen. However, the rate was reduced compared to normal skin fibroblasts. Cells grown from the tumors synthesized type I collagen, but no type III could be detected. After serial passaging the cultures started to produce type III collagen, which is probably due to a slow overgrowth by normal fibroblasts

Exit Survey of Undergraduate Students Completing Degrees in Summer 2011, Fall 2011, Winter 2012, and Spring 2012: Descriptive Statistics

The Exit Survey of Undergraduate Students Completing Degrees in Summer, 2011 through Spring of 2012 (Exit Survey) is the fourth survey of graduating students conducted at Western Washington University. This survey is designed to illuminate departmental-, college-, and university-level information on student satisfaction, barriers to success, experiences in upper division courses, and postgraduation plans. The exit survey also includes questions submitted to the Office of Survey Research (OSR) by the Division of Enrollment and Student Services, University Residences, and the Vice Provost of Undergraduate Education. The Exit Survey consists of a mixture of open-ended, multiple-choice and numerical response questions. This report provides descriptive statistics of the multiple choice and numerical response questions. In previous exit surveys, OSR surveyed only spring graduates. This exit survey includes responses from students graduating in summer 2011, fall 2011 and winter 2012 quarters, in addition to spring 2012. This means that OSR contacted every student graduating between summer 2011 and spring 2012. Because of this, the sample size of all graduates contacted nearly doubled from 1,574 in the 2011 survey of spring quarter graduates to 2,964 graduates between summer, 2011 and spring, 2012. OSR is pleased to note that 2,150 students responded to the survey, representing 72.6% of all graduates, a response rate nearly 10% higher and covering a broader base than a year ago. OSR initiated the Exit Survey during the fifth week of each quarter with an e-mail sent by the chair of the recipient’s major department. This e-mail requested that respondents complete the Exit Survey using a link embedded within the e-mail. A follow-up e-mail from OSR was typically sent three days later to non-respondents and then the process was repeated to non-respondent’s off-campus e-mail address about one week later. OSR then sent a reminder to internal email addresses the following week, and again to external addresses the subsequent week. Non-respondents were then contacted with phone call requests for their participation. This process ended the day before each quarter’s graduation exercises. As with any voluntary survey, readers should be concerned about sample selection bias; that is bias which arises because survey respondents are not a random selection from the population of survey recipients. While sample selection bias for the Exit Survey is mitigated through proper survey techniques and a high response rate, its presence should be considered when evaluating the data. Section A of this document reports basic demographic and academic statistics of the 2012 spring graduates who responded to the survey and compares these to non-respondents. As found in the general literature on surveys, women were more likely to complete the survey (64.1% of respondents were women whereas 61% of graduates were women). Respondents appear to be slightly better students as measured by the admissions index (average of 58.7 for respondents versus 57.6 for all graduates) and WWU GPA (average of 3.20 for respondents versus 3.17). In other ways, respondents and non-respondents were remarkably similar. For instance, 23.2% of respondents were minorities while 21.6% of graduates were minorities. The average and median age of respondents and non-respondents were nearly identical and measures of first generation, transfer status, Washington residency, cumulative WWU credits earned, and credits taken during their final quarter on campus were very similar. Because graduates of summer, fall, and winter quarters are potentially different than students who graduate in the spring, the inclusion of these students may make comparisons with prior surveys that excluded these students difficult. Indeed, Section A.3 demonstrates that spring quarter graduates tend to have higher admissions indices than those graduating in other quarters (60.0 for spring quarter, 55.9 for summer quarter), have higher WWU GPAs, are less likely to be former running start students (especially relative to those who graduate in the fall), are more likely to be in a non-Bellingham program. Because of these differences, for comparison purposes OSR will provide statistics on 2012 spring quarter graduates to those who request them. The remainder of this report contains university-level summary statistics of each question asked (Section B). This data is then disaggregated by college (Section C) and disaggregated again by department (Sections D through J). Section K presents data from all questions by transfer/native-freshmen status. The appendices to this report present count data on two of the open ended questions: “In what ways has Western exceeded your expectations?” and “In what ways has Western fallen short of your expectations?” Hopefully, this disaggregation of data will aid colleges and departments in their self-assessment efforts. While OSR will leave it to the reader to decide what is informative or striking in this report, we undertake to point out some findings which the wider campus may find interesting. If provided the opportunity to start over, 84% of respondents would attend Western again; a number similar to those reported each year since OSR initiated exit surveys in 2009. Of those who would not attend Western again, the most frequently given reasons were that another school has a better program in the student’s field of study and the student felt like they settled for a second-rate experience when they should have tried harder to get into a better school. It is important to note that these responses varied considerably across colleges with relative few CBE or Woodring students claiming another school had a better program. When asked about the length of time it took to graduate relative to their expectations at the time of enrollment, 65% of students claimed it took “less time than expected” or “as long as expected.” However, among those who graduated in the spring quarter, this rises to 74%, a result similar to prior surveys. For students who took longer to graduate than expected, the most frequently cited reasons for the delays were “I could not get the classes I needed” and “I changed my major.” This survey represents the first time the response regarding unavailable classes was one of the top two reasons listed for delayed graduation. This is reinforced by only 63% of students feeling “very satisfied” or “satisfied” with course availability within their major. Again, these data vary considerably by college with Fairhaven students demonstrating highest average satisfaction with course availability and Huxley students demonstrating the least satisfaction. When asked about their upper division studies, 90% of students expressed a positive level of satisfaction with the knowledge and expertise of faculty and 85% were positively satisfied with the quality of instruction and the level of academic challenge. Sixty-five percent of students collaborated with a professor on a research or creative project outside, an increase of 7% over the prior year. 75% of these students indicated that this experience contributed “quite a bit” or “a lot” to their learning. The average student graduated with an educational debt of just over $14,000, an increase of$1,000 over the prior year. However, this average hides the fact that 40% of graduates completed their education with no debt whatsoever. The average debt of those who did borrow was $25,445, an amount almost$2000 greater than the prior year. Eighteen percent of students indicated that their student loans impacted their decision to pursue a particular career. Fifty-nine percent of students indicated that their principal activity upon graduation was full-time employment while 17% expect to work part-time, increases of 3% and 4% over the past year. Of those expecting to work, 45% were looking for, but unable to find a job at the time of survey completion, a number similar to the prior year. Thirteen percent of graduates hoped to attend a graduate program and of these, 36% had accepted an offer of admission. One feature of the Exit Survey is that respondents are tracked using their W number which provides OSR the opportunity to merge the student data with Western’s records and past OSR surveys. This ability profoundly opens the door to analysis of longitudinal issues that would otherwise be impossible. OSR is happy to share data or provide survey services upon request