Magnetization driven metal - insulator transition in strongly disordered Ge:Mn magnetic semiconductors

We report on the temperature and field driven metal-insulator transition in disordered Ge:Mn magnetic semiconductors accompanied by magnetic ordering, magnetoresistance reaching thousands of percents and suppression of the extraordinary Hall effect by a magnetic field. Magnetoresistance isotherms are shown to obey a universal scaling law with a single scaling parameter depending on temperature and fabrication. We argue that the strong magnetic disorder leads to localization of charge carriers and is the origin of the unusual properties of Ge:Mn alloys.Comment: 10 pages, 5 figure

A novel fluorescence in situ hybridization test for rapid pathogen identification in positive blood cultures

AbstractA novel molecular beacon-based fluorescence in situ hybridization (FISH) test allowing for the identification of a wide range of bacterial pathogens directly in positive blood cultures (BCs) was evaluated with positive BCs of 152 patients. Depending on the Gram stain, either a Gram-negative or a Gram-positive panel was used. The time to result was 30 min, and the hands-on time was only 10 min. Seven per cent of the cultured microorganisms were not included in the FISH panels; the identification rate of those included was 95.2%. Overall, the FISH test enabled accurate pathogen identification in 88.2% of all cases analysed

In Vitro Viability and Cytotoxicity Testing and Same-Well Multi-Parametric Combinations for High Throughput Screening

In vitro cytotoxicity testing has become an integral aspect of drug discovery because it is a convenient, costeffective, and predictive means of characterizing the toxic potential of new chemical entities. The early and routine implementation of this testing is testament to its prognostic importance for humans. Although a plethora of assay chemistries and methods exist for 96-well formats, few are practical and sufficiently sensitive enough for application in high throughput screening (HTS). Here we briefly describe a handful of the currently most robust and validated HTS assays for accurate and efficient assessment of cytotoxic risk. We also provide guidance for successful HTS implementation and discuss unique merits and detractions inherent in each method. Lastly, we discuss the advantages of combining specific HTS compatible assays into multi-parametric, same-well formats

Delta-Function Potential with a Complex Coupling

We explore the Hamiltonian operator H=-d^2/dx^2 + z \delta(x) where x is real, \delta(x) is the Dirac delta function, and z is an arbitrary complex coupling constant. For a purely imaginary z, H has a (real) spectral singularity at E=-z^2/4. For \Re(z)<0, H has an eigenvalue at E=-z^2/4. For the case that \Re(z)>0, H has a real, positive, continuous spectrum that is free from spectral singularities. For this latter case, we construct an associated biorthonormal system and use it to perform a perturbative calculation of a positive-definite inner product that renders H self-adjoint. This allows us to address the intriguing question of the nonlocal aspects of the equivalent Hermitian Hamiltonian for the system. In particular, we compute the energy expectation values for various Gaussian wave packets to show that the non-Hermiticity effect diminishes rapidly outside an effective interaction region.Comment: Published version, 14 pages, 2 figure

Spherical-box approach for resonances in presence of Coulomb interaction

The spherical-box approach is extended to calculate the resonance parameters and the real part of the wave function for single particle resonances in a potential containing the long-range Coulomb interaction. A model potential is taken to demonstrate the ability and accuracy of this approach. The calculated resonance parameters are compared with available results from other methods. It is shown that in the presence of the Coulomb interaction, the spherical-box approach works well for not so broad resonances. In particular, for very narrow resonances, the present method gives resonance parameters in a very high precision.Comment: 10 pages, 5 EPS figures; to be published in J. Phys.

Pseudo-time Schroedinger equation with absorbing potential for quantum scattering calculations

The Schroedinger equation with an energy-dependent complex absorbing potential, associated with a scattering system, can be reduced for a special choice of the energy-dependence to a harmonic inversion problem of a discrete pseudo-time correlation function. An efficient formula for Green's function matrix elements is also derived. Since the exact propagation up to time 2t can be done with only t real matrix-vector products, this gives an unprecedently efficient scheme for accurate calculations of quantum spectra for possibly very large systems.Comment: 9 page

Complications after intestinal resection in Crohn's disease: laparoscopic versus conventional approach

AbstractBackgroundsignificant advances in medical therapy for Crohn's disease (CD) occurred in the last 12 years, mainly due to the introduction of anti-TNF therapy. Laparoscopic colorectal surgery represented the most important advance on surgical treatment in the management of CD, as it also had developed in the treatment of other conditions. There is a tendency for lower complication rates after laparoscopic bowel resections as compared to open surgery. The aim of this study was to analyze and compare the complication rates after bowel resections for CD between the two approaches in a Brazilian case series.Methodsthis was a retrospective longitudinal study, including CD patients submitted to bowel resections from a single Brazilian Inflammatory Bowel Diseases (IBD) referral center, treated between January 2008 and June 2012 with laparoscopic approach (LA) or conventional approach (CA).Variables analyzedage at surgery, gender, Montreal classification, smoking, concomitant medication, type of surgery, surgical approach, presence and type of complication up to 30 days after the procedures. Readmission and reoperation rates, as well as mortality, were also analyzed. Patients were allocated in two groups regarding the type of procedure (LA or CA), and complication rates and characteristics were compared. Statistical analysis was performed with Mann-Whitney test (quantitative variables) and chi-square test (qualitative variables), with p < 0.05 considered significant.Resultsa total of 46 patients (25 men) were included (16 submitted to LA), with mean age of 38.1 (± 12.7) years. The groups were considered homogeneous according to age, gender, CD location, perianal disease and concomitant medications. There were more patients with fistulizing CD on the CA group (p = 0.029). The most common procedure performed was ileocolic resection on both groups (56.7% of the CA and 75% of the LA patients – p = 0.566). Overall, total complications (surgical and medical, including minor and major issues) oc- curred in 60% (18/30) of the CA group and 12.5% (2/16) of the LA group (p = 0.002). Wound in- fection was the most frequent complication (10/30 on CA and 1/16 on the LA groups). There were 3 deaths in the CA group. Specific analysis of each complication did not demonstrate any difference between the groups regarding abdominal sepsis, urinary tract infections, pneumonia, readmission, reoperations and deaths (p = 0.074).Conclusionsthere was a higher complication rate in patients operated with CA as compared to LA. This was probably due to patient selection for the laparoscopic approach, with severe cases, mostly due to fistulizing abdominal CD, being operated mainly by open surgery. LA tends to be the recommended approach in most cases of non-complicated CD