Topological Quantum Field Theory and Seiberg-Witten Monopoles

A topological quantum field theory is introduced which reproduces the Seiberg-Witten invariants of four-manifolds. Dimensional reduction of this topological field theory leads to a new one in three dimensions. Its partition function yields a three-manifold invariant, which can be regarded as the Seiberg-Witten version of Casson's invariant. A Geometrical interpretation of the three dimensional quantum field theory is also given.Comment: 15 pages, Latex file, no figure

Malignancy within a tail gut cyst:a case of retrorectal carcinoid tumour

Purpose. Tailgut cysts with malignant transformation are rare entities. We discuss the diagnostic strategy and treatment of a malignancy within a tailgut cyst. Methods. In this study we report on the case of a 61-year-old man with a malignant neuroendocrine tumour arising within a tailgut cyst and an overview of the literature emphasising the histopathological characteristics and differential diagnosis. Results. Our patient presented with lower back pain, rectal pain, and increased urgency of defecation. MRI scan and CT-guided biopsy on histological analysis revealed a diagnosis of carcinoid tumour of the presacral space. The patient subsequently underwent an abdominoperineal excision of the rectum. Conclusions. This case highlights the importance of tailgut cysts as a differential diagnosis of presacral masses. It is a rare congenital lesion developing from remnants of the embryonic postanal gut and is predominantly benign in nature. Approximately half of cases remain asymptomatic; therefore, diagnosis is often delayed. Magnetic resonance imaging is the investigation of choice and an awareness of the possibility of malignant potential is critical to avoiding missed diagnosis and subsequent morbidity. Complete surgical excision allows accurate diagnosis, confirmation of oncological clearance, and prevention of mortality

Two cases of fungal keratitis caused by Metarhizium anisopliae

We present two cases of keratitis due to Metarhizium anisopliae in geographically separated areas of the United States. The isolates were microscopically similar but morphologically different and were identified by ribosomal DNA sequencing. Both isolates had low minimum inhibitory concentration (MIC) values to caspofungin and micafungin, but high MIC values to amphotericin B. The morphologic and antifungal susceptibility differences between the two isolates indicate possible polyphylogeny of the group. Keywords: Metarhizium, Fungal keratitis, Keratomycosis, Antifungal susceptibilit

Defining and Characterizing Differences in College Alcohol Intervention Efficacy: A Growth Mixture Modeling Application

Objective: While college alcohol misuse remains a pervasive issue, individual-level interventions are among the most efficacious methodologies to reduce alcohol-related harms. Growth mixture modeling (GMM) was used as an exploratory moderation analysis to determine how many types of college drinkers exist with regard to intervention efficacy over a 12-month period. Method: Data from 3 randomized controlled trials were combined to yield a sample of 1,040 volunteer and mandated college students who were given 1 of 3 interventions: a brief motivational intervention, Alcohol Edu for Sanctions, or Alcohol 101 Plus. Participants were assessed at baseline, and 1, 6, and 12 months post intervention. Results: Through the examination of heavy drinking behaviors, piecewise GMM identified 6 subpopulations of drinkers. Most of the sample (76%) was lighter drinkers who demonstrated a strong intervention response, but returned to baseline behaviors over the subsequent 12 months. In contrast, 11% of the sample reported no significant change over the 12-month period. Four minority subpopulations were also identified. In sum, 82% of the sample responded to intervention, but 84% of the sample reported intervention decay over the subsequent 12 months. Female gender, being an, upperclassmen, beginning drinking later in life, not engaging in drinking games, and lower norms predicted a greater likelihood of responding to intervention. Conclusion: Individual-level interventions are successful at effecting change in most college students, but these effects tend to decay to baseline behaviors by 12 months. These results suggest intervention efforts need to find ways to engage freshmen men and those who play drinking games. Public Health Significance: This study suggests that there are distinct subgroups of college students defined by how they respond to alcohol intervention, and that interventions need to target freshmen men and those who play drinking games. Although most students initially response to intervention effects, most also show intervention decay over the next 12 months, which suggests that we need to determine ways of improving the long-term effects of alcohol interventions

Generalized Particle Statistics in Two-Dimensions: Examples from the Theory of Free Massive Dirac Field

In the framework of algebraic quantum field theory we analyze the anomalous statistics exhibited by a class of automorphisms of the observable algebra of the two-dimensional free massive Dirac field, constructed by fermionic gauge group methods. The violation of Haag duality, the topological peculiarity of a two-dimensional space-time and the fact that unitary implementers do not lie in the global field algebra account for strange behaviour of statistics, which is no longer an intrinsic property of sectors. Since automorphisms are not inner, we exploit asymptotic abelianness of intertwiners in order to construct a braiding for a suitable $C^*$-tensor subcategory of End($\mathscr{A}$). We define two inequivalent classes of path connected bi-asymptopias, selecting only those sets of nets which yield a true generalized statistics operator.Comment: 24 page

Comparison of sample preparation methods, instrumentation platforms, and contemporary commercial databases for identification of clinically relevant mycobacteria by matrix-assisted laser desorption ionization - Time of flight mass spectrometry

When mycobacteria are recovered in clinical specimens, timely species-level identification is required to establish the clinical significance of the isolate and facilitate optimization of antimicrobial therapy. Matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) has recently been reported to be a reliable and expedited method for identification of mycobacteria, although various specimen preparation techniques and databases for analysis are reported across studies. Here we compared two MALDI-TOF MS instrumentation platforms and three databases: Bruker Biotyper Real Time Classification 3.1 (Biotyper), Vitek MS Plus Saramis Premium (Saramis), and Vitek MS v3.0. We evaluated two sample preparation techniques and demonstrate that extraction methods are not interchangeable across different platforms or databases. Once testing parameters were established, a panel of 157 mycobacterial isolates (including 16 Mycobacterium tuberculosis isolates) was evaluated, demonstrating that with the appropriate specimen preparation, all three methods provide reliable identification for most species. Using a score cutoff value of ≥1.8, the Biotyper correctly identified 133 (84.7%) isolates with no misidentifications. Using a confidence value of ≥90%, Saramis correctly identified 134 (85.4%) isolates with one misidentification and Vitek MS v3.0 correctly identified 140 (89.2%) isolates with one misidentification. The levels of accuracy were not significantly different across the three platforms (P = 0.14). In addition, we show that Vitek MS v3.0 requires modestly fewer repeat analyses than the Biotyper and Saramis methods (P = 0.04), which may have implications for laboratory workflow