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In this work, we use the quantum-jump approach to study light-matter interactions in a four-level scheme giving rise to frequency up-conversion amplification without inversion (AWI). The results obtained apply to the case of neutral Hg vapour where, recently, it has been reported AWI of a probe field in the UV regime, opening the way for lasing without inversion in this range of frequencies. We show that, in this scheme, the key element to obtain maximum amplification is the fulfillment of the three-photon resonance condition, which favors coherent evolution periods associated with the probe field gain. We also investigate the parameter values in order to optimize amplification. The present study extends the theoretical understanding of the underlying mechanisms involved in AWI., Comment: 10 pages, 9 figures

This paper describes studies performed to understand the biocompatibility of TiO2 thin films with controlled crystalline phases using human pigment epithelium cells (ARPE-19). TiO2 films we...

BACKGROUND Different types of ventricular arrhythmias (monomorphic ventricular tachycardia [VT], polymorphic VT, or ventricular fibrillation) can be detected by implantable cardiac defibrillators (ICDs) in fast VT zone. The efficacy of antitachycardia pacing (ATP) depends on the type of the treated arrhythmia. We hypothesized that an automatic algorithm based on morphological affinity of ICD far-field electrograms during tachycardia can predict ATP success and the need of shock. METHODS The algorithm was evaluated on ventricular arrhythmias recorded in CareLink ICD remote monitoring system (Medtronic Inc., Minneapolis, MN, USA). Patients were selected if first ATP programmed was a burst of eight pulses at 88% coupling interval and if a far-field electrogram was available. The algorithm calculated a stability coefficient (SC) for all their stored ATP-treated fast ventricular arrhythmia (VA) episodes (LC 200-300 ms), analyzing the morphology homogeneity of the last eight recorded far-field electrograms before ventricular arrhythmias detection. RESULTS Inclusion criteria were fulfilled by 717 patients from 29 centers. Three hundred and twenty fast VA were recorded in 103 patients. A higher SC was observed in episodes terminated with the first-ATP (0.78 [0.72-0.84] vs 0.74 [0.60-0.84]; P = 0.006). These differences were especially marked among the 62 episodes of very fast VA (CL ≤250 ms) (0.77 [0.74-0.85] vs 0.64 [0.51-0.8]; P = 0.006). In the multivariate analysis, a SC > 70% was independently associated with a higher likelihood of first-ATP success (odds ratio [OR] = 2.5; [95% confidence interval (CI) = 1.4-4.5], P = 0.001) and a lower need of shock (OR = 0.37; [95% CI = 0.2-0.7], P = 0.002). CONCLUSION This automatic algorithm (stability coefficient) shows that ATP therapy response can be predicted in fast ventricular arrhythmias through morphology evaluation.

In this work, we propose a method to create an atomic frequency comb (AFC) in hot atomic vapors using the piecewise adiabatic passage (PAP) technique. Due to the Doppler effect, the trains of pulses used for PAP give rise to a velocity-dependent transfer of the atomic population from the initial state to the target one, thus forming a velocity comb whose periodicity depends not only on the repetition rate of the applied pulses but also on the specific atomic transitions considered. We highlight the advantages of using this transfer technique with respect to standard methods and discuss, in particular, its application to store a single telecom photon in an AFC quantum memory using a high density Ba atomic vapor., Comment: 12 pages, 9 figures

We investigate spatial adiabatic passage of a Bose-Einstein condensate in a triple well potential within the three-mode approximation. By rewriting the dynamics in the so-called time-dependent dark/dressed basis, we analytically derive the optimal conditions for the non-linear parameter and the on-site energies of each well to achieve a highly efficient condensate transport. We show that the non-linearity yields a high-efficiency plateau for the condensate transport as a function of the on-site energy difference between the outermost wells, favoring the robustness of the transport. We also analyze the case of different non-linearities in each well, which, for certain parameter values, leads to an increase of the width of this plateau., Comment: 10 pages, 7 figures

Information Technology and Infrastructure Library (ITIL) is a fundamental need for any company or industry, especially for Small and Medium Enterprises (SMEs). However, there is an increasing demand on how to proceed to correctly implement it. There is not a clear guide, methodology or algorithm for it. The first step to take into account is to understand the current implementation level of ITIL processes in SMEs. Knowing the current level will help to set up a solution. In this paper, we present the results and analysis of a survey done in 64 small and medium enterprises of Madrid, Spain. The results let us knowing the current implementation level of ITIL processes.

In this paper we show how to compute the normalizing and the system matrix terms of the EM-ML reconstruction algorithm for rotating planar detector PET scanners. The method introduced is valid for either pixelated or continuous scintillators. We base our computations in geometrical considerations, but other effects of the PET process can be easily included. In this regard, the intrinsic resolution of the detection system, the depth of interaction (DOI) of the incident gamma rays and the efficiency of the scintillators have been modeled in our development. The computation of the normalizing term and the system matrix is valid for any basis function used for the discrete approximation of the radionuclide concentration. We show that our computations are comparable to those of a Monte Carlo method at a small fraction of the computational cost.

Coating building materials with anti-graffiti treatments hinders or prevents spray paint adherence by generating low energy surfaces. This paper describes the effect of coating cement paste, lime mortar, granite, limestone and brick with two anti-graffiti agents (a water-base fluoroalkylsiloxane, “Protectosil Antigraffiti®”, and a Zr ormosil) on the dispersive component of the surface energy of these five construction materials. The agents were rediluted in their respective solvents at concentrations of 5 and 75% and the values were determined with inverse gas chromatography at infinite dilution (IGC-ID). The dispersive energy of the five materials prior to coating, ranked from highest to lowest, was as follows: limestone > granite > cement paste > brick > lime mortar. After application of the two anti-graffiti compounds, CF3 terminals (Protectosil) were found to reduce the surface energy of both basic (limestone and lime mortar) and acidic (granite) substrates more effectively than CH3 (ormosil) terminals., Acknowledgements Funding from the Spanish Ministry of Education and Science (Projects MAT 2003-40008343 and CONSOLIDER CSD2007-00058) and the Regional Government of Madrid 401(Geomaterials Programme) is gratefully acknowledged. Paula María Carmona Quiroga, 402grantee with the CSIC’s Cultural Heritage Theme Networ, participated in this study 403under a European Social Fund and Spanish National Research Council (CSIC) 404Integrated Employability Pathway(I3P)pre-doctoral grant. The authors wish to thank 405Degussa, and specifically Ana de Pedro, for providing th e fluorinated anti-graffiti.

A novel radiofrequency ablation catheter has been developed with integrated custom designed optics, enabling real-time monitoring of radiofrequency ablation procedures through polarization-sensitive optical coherence reflectometry. The optics allow for proper tissue illumination through a view-port machined in the catheter tip, thus providing lesion depth control over the RF ablation treatment. The system was verified in an in-vitro model of swine myocardium. Optical performance and thermal stability was confirmed after more than 25 procedures, without any damage to the optical assembly induced by thermal stress or material degradation. The use of this catheter in RF ablation treatments may make possible to assess lesion depth during therapy, thus translating into a reduction of potential complications on the procedure.

Les auteurs rapportent l'observation d'un nouveau-ne de sexe masculin chez qui une atresie anale sans fistule evidente fut diagnostiquee. De ce fait, on pratiqua seulement une anoproctoplastie par voie perineale. Dans les suites, on observa la survenue d'une infection des voies urinaires et en particuIier une orchiepididymite gauche. La cysto-urethrographie montra un reflux dans le canal deferent droit, dans les vesicules seminales droites de meme que dans l'epididyme et le testicule droit. Une rectoscopie put alors affirmer l'existence d'une fistule recto-urethrale. Apres separation chirurgicale des deux conduits, les symptomes disparurent. Cette observation est inhabituelle car les manifestations d'orchiepididymite compliquant une fistule dans le cadre de l'atresie anale sont rares. Dans l'atresie anale, la fistule recto ou ano-urethrale n'est pas toujours mise en evidence sur le plan radiologique car elle peut etre bouchee au depart en particulier par des matieres

Resumen basado en el de la publicación Resumen en inglés Se presenta un estudio experimental detallado sobre los diferentes procesos de calentamiento y enfriamiento que permite deducir la variación de temperatura, en estos procesos, el transcurso del tiempo no es siempre el mismo, y depende, en gran medida, de cómo se lleva a cabo el proceso. Por lo tanto, confundir las relaciones T-Q (siempre lineales) con las relaciones T-t (depende del proceso) es un error que es necesario evitar en las clases. ESP

Some of the causes which may account for the high incidence of tuberculosis in children in our environment have been analyzed. Twelve cases of tuberculosis have been included in the study (seven pulmonary cases, two cases of bone tuberculosis, one nodosum erythema and one miliary tuberculosis in an HIV positive patient). Based upon our series, we report on some mistakes in the diagnosis, specific treatment and chemoprophylaxis. We have tried to briefly outline the steps which should be taken to overcome these problems.

We have carried out an experimental model of urinary diversion and dis-diversion on male Wistar rats in order to study the complications that are produced after diversion, as well as to see whether the alterations continue unchanged, or increase, or diminish after dis-diversion. The following experimental design was used: a control group made up of 48 animals an a problem group of 200 animals all submitted to vesicosigmoidostomy of which 100 were designed to be subsequently dis-diverted. The sacrificed animals (n = 112) were studied for somatic, biochemical and histological parameters. Statistical comparison of the problem group with the controls showed significant differences for the somatic and biochemical parameters, especially in the form of weight-size retardation, increase of urea, creatinine, calcium, phosphorus, uric acid, cholesterol, transaminase, alkaline phosphatase, sodium and chlorine and decrease in albumin and total proteins. After dis-diversion there is an improvement of some of these parameters without reaching total normalization. This leads us to think that either the lesions are irreversible, or more time after dis-diversion is needed for there to be reversibility. We also describe the histological lesions found at the level of the vesicointestinal anastomosis, and the mortality of our series which is higher than that presented by females, a fact inducing us to think that factors exist in the male which increase the mortality.

Though there are not many cases described in the literature and very few for children, the existence of lower urodigestive communications may give rise to inflammatory processes in gonads and gonaducts in the male. We have carried out an experimental study of this aspect on 248 male Wistar rats according to the following design: A 48 animal control group (C) is divided into four equal subgroups sacrificed at the ages of one, two, three and four months. The problem group (P) of 200 animals are all submitted to vesicosigmoidostomy and then 100 are sacrificed after one and two months, and the other 100 are dis-diverted one and two months after the original diversion and sacrificed one month later. No histological alterations were observed in gonads and gonaducts for the sacrificed control animals (n = 48). The animals sacrificed after diversion (44 per 100) showed the following histological alterations: five cases of testicular tube necrosis, two cases of deferent conduit inflammation, one case of deferent conduit necrosis, 12 cases of epididymis inflammation and 13 cases of epididymis necrosis. The animals that also underwent dis-diversion and that were later sacrificed (20 per 100) showed: five cases of testicular tube necrosis, one case of testicular inflammation, two cases of deferent conduit inflammation, four cases of epididymis inflammation and seven cases of epididymis necrosis. Statistical analysis showed that the differences between the two P groups were not significant.(ABSTRACT TRUNCATED AT 250 WORDS)

A case of condyloma acuminata occupying almost the entire penile urethra is reported herein. The literature is reviewed highlighting its etiopathogenesis, histologic features, and treatment according to the stage of the disease. The different treatment modalities that have been utilized and those currently used are described, with a special emphasis on the increasing importance of laser therapy. Some considerations are presented relative to diagnosis, and a therapeutic protocol according to the stage of the disease is described. Due to the high incidence of recurrence, close follow-up of these patients is advocated.

In this paper we consider four operators arising in harmonic analysis in R', n > 1. They share one feature: each is known to be bounded on LP for all 1 < p < o, but for each it has been an open question whether a weak type (1, 1) bound also holds. In two cases we show that the weak (1, 1) bound does hold, and for the others we establish weaker estimates which are still sharper than the LP boundedness. Although the four operators are quite distinct, they all involve convolution kernels which are related to the singular integrals of Calderon and Zygmund, but which lack the smoothness required for the usual analysis. In each case this defect is mitigated by the presence of some form of curvature. Consider the Bochner-Riesz means

The authors describe a case of testicle-based teratoma, in a 20-month old boy. Due to the characteristics of the palpation and its eventual transillumination, it may be confused with a hydrocele. They stress its rarity and on the basis of a review of the literature, they explain its histological peculiarities and refer to its prognosis, usually benign, when it is diagnosed at about 2 years of age, providing that a very careful examination of the histological sections rules out the presence of anaplastic cells. Finally there is a short discussion on the possibilities of complementary therapy when there are metastases.

We report a case of calyceal diverticulum which evolved into what appeared anatomically and radiologically as a simple renal cyst. Similarities and differences between both entities are discussed based on a review of the literature. Our case report suggests that both conditions are related and that they can even be considered as evolutive forms of the same disease.

Four cases of multivesicular hepatic hydatidosis are reported. Two of them were affected by exogenous growth. All patients had undergone a long-term treatment with mebendazole at the usual doses. We are contrasting our experience in the use of such drug and the previous reports by other authors. In our opinion, as mebendazole acts on the cyst in a double way (both inhibiting glucose uptake by the larva and modifying the structure of the cyst membranes) ir induces the cyst multivesiculation which is a sign of suffering or resistance of the parasite. Despite the fact that previous reports, and also one of the cases reported by us, point to a favourable evolution of the hepatic hydatidosis after treatment with Mebendazole, the possibility that the multivesicular cyst-with a more spreading growth and a surgical treatment which is occasionally more difficult, may be induced by that drug would perhaps discourage its use.