DBI with Primordial Magnetic Field in the Sky

In this paper, we study the generation of a large scale magnetic field with amplitude of order $\mu$G in an inflationary model which has been introduced in hep-th/0310221. This inflationary model based on existence of a speed limit for inflaton field. Generating a mass for inflaton at scale above the $\phi_{IR}$, breaks the conformal triviality of the Maxwell equation and causes to originate a magnetic field during the inflation. The amplitude strongly depends on the details of reheating stage and also depends on the e-foldings parameter N. We find the amplitude of the primordial magnetic field at decoupling time in this inflationary background using late time behavior of the theory.Comment: 12 pages, no figure, typos correcte

Sequential drain amylase to guide drain removal following pancreatectomy

BACKGROUND: Although used as criterion for early drain removal, postoperative day (POD) 1 drain fluid amylase (DFA) ≤ 5000 U/L has low negative predictive value for clinically relevant postoperative pancreatic fistula (CR-POPF). It was hypothesized that POD3 DFA ≤ 350 could provide further information to guide early drain removal. METHODS: Data from a pancreas surgery consortium database for pancreatoduodenectomy and distal pancreatectomy patients were analyzed retrospectively. Those patients without drains or POD 1 and 3 DFA data were excluded. Patients with POD1 DFA ≤ 5000 were divided into groups based on POD3 DFA: Group A (≤350) and Group B (>350). Operative characteristics and 60-day outcomes were compared using chi-square test. RESULTS: Among 687 patients in the database, all data were available for 380. Fifty-five (14.5%) had a POD1 DFA > 5000. Among 325 with POD1 DFA ≤ 5000, 254 (78.2%) were in Group A and 71 (21.8%) in Group B. Complications (35 (49.3%) vs 87 (34.4%); p = 0.021) and CR-POPF (13 (18.3%) vs 10 (3.9%); p < 0.001) were more frequent in Group B. CONCLUSIONS: In patients with POD1 DFA ≤ 5000, POD3 DFA ≤ 350 may be a practical test to guide safe early drain removal. Further prospective testing may be useful

Stretched Polymers in a Poor Solvent

Stretched polymers with attractive interaction are studied in two and three dimensions. They are described by biased self-avoiding random walks with nearest neighbour attraction. The bias corresponds to opposite forces applied to the first and last monomers. We show that both in $d=2$ and $d=3$ a phase transition occurs as this force is increased beyond a critical value, where the polymer changes from a collapsed globule to a stretched configuration. This transition is second order in $d=2$ and first order in $d=3$. For $d=2$ we predict the transition point quantitatively from properties of the unstretched polymer. This is not possible in $d=3$, but even there we can estimate the transition point precisely, and we can study the scaling at temperatures slightly below the collapse temperature of the unstretched polymer. We find very large finite size corrections which would make very difficult the estimate of the transition point from straightforward simulations.Comment: 10 pages, 16 figure

Gluon self-energy in a two-flavor color superconductor

The energy and momentum dependence of the gluon self-energy is investigated in a color superconductor with two flavors of massless quarks. The presence of a color-superconducting quark-quark condensate modifies the gluon self-energy for energies which are of the order of the gap parameter. For gluon energies much larger than the gap, the self-energy assumes the form given by the standard hard-dense loop approximation. It is shown that this modification of the gluon self-energy does not affect the magnitude of the gap to leading and subleading order in the weak-coupling limit.Comment: 21 pages, 6 figures, RevTeX, aps and epsfig style files require

Anomalous Hopping Exponents of Ultrathin Films of Metals

The temperature dependence of the resistance R(T) of ultrathin quench-condensed films of Ag, Bi, Pb and Pd has been investigated. In the most resistive films, R(T)=Roexp(To/T)^x, where x=0.75. Surprisingly, the exponent x was found to be constant for a wide range of Ro and To in all four materials, possibly implying a consistent underlying conduction mechanism. The results are discussed in terms of several different models of hopping conduction.Comment: 6 pages, 5 figure

Ground-state properties of tubelike flexible polymers

In this work we investigate structural properties of native states of a simple model for short flexible homopolymers, where the steric influence of monomeric side chains is effectively introduced by a thickness constraint. This geometric constraint is implemented through the concept of the global radius of curvature and affects the conformational topology of ground-state structures. A systematic analysis allows for a thickness-dependent classification of the dominant ground-state topologies. It turns out that helical structures, strands, rings, and coils are natural, intrinsic geometries of such tubelike objects

Evidence Vs. Practice in Early Drain Removal Following Pancreatectomy

Background: Early drain removal when postoperative day (POD) 1 drain fluid amylase (DFA) was ≤ 5000 U/L reduced complications in a previous randomized controlled trial. We hypothesized that most surgeons continue to remove drains late and this is associated with inferior outcomes. Methods: We assessed the practice of surgeons in a prospectively maintained pancreas surgery registry to determine the association between timing of drain removal with demographics, co-morbidities, and complications. We selected patients with POD1 DFA ≤ 5000 U/L and excluded those without drains, and subjects without data on POD1 DFA or timing of drain removal. Early drain removal was defined as ≤ POD5. Results: 244 patients met inclusion criteria. Only 90 (37%) had drains removed early. Estimated blood loss was greater in the late removal group (190 mL vs 100 mL, p = 0.005) and pathological findings associated with soft gland texture were more frequent (97(63%) vs 35(39%), p < 0.0001). Patients in the late drain removal group had more complications (84(55%) vs 30(33%), p = 0.001) including pancreatic fistula (55(36%) vs 4(4%), p < 0.0001), delayed gastric emptying (27(18%) vs 3(3%), p = 0.002), and longer length of stay (7 days vs 5 days, p < 0.0001). In subset analysis for procedure type, complications and pancreatic fistula remained significant for both pancreatoduodenectomy and distal pancreatectomy. Conclusion: Despite level 1 data suggesting improved outcomes with early removal when POD1 DFA is ≤ 5000 U/L, experienced pancreas surgeons more frequently removed drains late. This practice was associated with known risk factors (EBL, soft pancreas) and may be associated with inferior outcomes suggesting potential for improvement

The Harris-Luck criterion for random lattices

The Harris-Luck criterion judges the relevance of (potentially) spatially correlated, quenched disorder induced by, e.g., random bonds, randomly diluted sites or a quasi-periodicity of the lattice, for altering the critical behavior of a coupled matter system. We investigate the applicability of this type of criterion to the case of spin variables coupled to random lattices. Their aptitude to alter critical behavior depends on the degree of spatial correlations present, which is quantified by a wandering exponent. We consider the cases of Poissonian random graphs resulting from the Voronoi-Delaunay construction and of planar, ``fat'' $\phi^3$ Feynman diagrams and precisely determine their wandering exponents. The resulting predictions are compared to various exact and numerical results for the Potts model coupled to these quenched ensembles of random graphs.Comment: 13 pages, 9 figures, 2 tables, REVTeX 4. Version as published, one figure added for clarification, minor re-wordings and typo cleanu

A Distinct Three-Factor Structure of Restricted and Repetitive Behaviors in an Epidemiologically Sound Sample of Preschool-Age Children with Autism Spectrum Disorder

Prior studies investigating restricted and repetitive behavior (RRB) subtypes within autism spectrum disorder (ASD) have found varied factor structures for symptom groupings, in part, due to variation in symptom measurement and broad sample age ranges. This study examined RRBs among 827 preschool-age children, ages 35 to 71 months, through an exploratory factor analysis of RRB items from the Autism Diagnostic Interview-Revised (ADI-R) collected through the Study to Explore Early Development. The factor structures of RRBs among children with confirmed ASD versus those with non-autism developmental concerns were qualitatively compared. Correlations between RRB factors and participant characteristics were examined in the ASD group. Three conceptually well-defined factors characterized as repetitive sensorimotor behaviors (RSMB), insistence on sameness (IS), and a novel stereotyped speech (SPEECH) factor emerged for the ASD group only. Distinct factors were supported by different clinical correlates. Findings have implications for improving differential diagnosis and understanding of ASD symptomatology in this age range

Calibration of Super-Kamiokande Using an Electron Linac

In order to calibrate the Super-Kamiokande experiment for solar neutrino measurements, a linear accelerator (LINAC) for electrons was installed at the detector. LINAC data were taken at various positions in the detector volume, tracking the detector response in the variables relevant to solar neutrino analysis. In particular, the absolute energy scale is now known with less than 1 percent uncertainty.Comment: 24 pages, 16 figures, Submitted to NIM