Dual amplitude with arbitrary trajectories

A crossing-symmetric amplitude with Regge behavior is proposed. With arbitrary Regge trajectories, it avoids ancestor and ghost difficulties and possesses second-sheet resonances which may be finite in number. The N-point and ππ amplitudes are given

Stream Fusion, to Completeness

Stream processing is mainstream (again): Widely-used stream libraries are now available for virtually all modern OO and functional languages, from Java to C# to Scala to OCaml to Haskell. Yet expressivity and performance are still lacking. For instance, the popular, well-optimized Java 8 streams do not support the zip operator and are still an order of magnitude slower than hand-written loops. We present the first approach that represents the full generality of stream processing and eliminates overheads, via the use of staging. It is based on an unusually rich semantic model of stream interaction. We support any combination of zipping, nesting (or flat-mapping), sub-ranging, filtering, mapping-of finite or infinite streams. Our model captures idiosyncrasies that a programmer uses in optimizing stream pipelines, such as rate differences and the choice of a "for" vs. "while" loops. Our approach delivers hand-written-like code, but automatically. It explicitly avoids the reliance on black-box optimizers and sufficiently-smart compilers, offering highest, guaranteed and portable performance. Our approach relies on high-level concepts that are then readily mapped into an implementation. Accordingly, we have two distinct implementations: an OCaml stream library, staged via MetaOCaml, and a Scala library for the JVM, staged via LMS. In both cases, we derive libraries richer and simultaneously many tens of times faster than past work. We greatly exceed in performance the standard stream libraries available in Java, Scala and OCaml, including the well-optimized Java 8 streams

An Upper Bound on the Higgs Boson Mass from a Positivity Condition on the Mass Matrix

We impose the condition that the eigenvalues of the mass matrix in the shifted Lagrangian density be positive at \phi=\phi_{0}, the vacuum expectation value of the scalar field. Using the one-loop effective potential of the standard model, this condition leads to an upper bound on the Higgs boson mass m_{H}: m_{H}<230GeV, for a top quark mass of 175GeV.Comment: LaTex, 5 page

Effect of electrolysis regimes on the structure and properties of coatings on aluminum alloys formed by anode-cathode microarc oxidation

Наведено результати дослідження фазового складу і властивостей МДО-покриттів на алюмінієвих сплавах. Покриття були одержані в лужно-селікатному електроліті на змінному сінусоідальному струмі і в імпульсному режимі струму. Показано, що підвищена щільність мікророзрядів при імпульсної технології збільшує сумарну енергію, що виділяється в них. Це обумовлює підвищення швидкості зростання оксидного покриття і ймовірність утворення α-Al₂O₃ фази. Одержані при мікроплазмове оксидуванні в імпульсному струмовому режимі покриття мають високу твердість і електричну міцніст

Problems of Bacteriological Pollution in Water Wells in Wadi Hadramout Water Project

This paper presents an existing problem of drinking water pollution for a small project and one of the model projects of drinking water in Yemen, designed to save and preserve good quality water for the present and future generations in the area. The paper gives the details of the project and explains the problem of bacteriological pollution and the steps undertaken to solve the problem. Some of the results for short-term solutions and recommendation for the long-term solutions are also given

Optimized FSO System Performance over Atmospheric Turbulence Channels with Pointing Error and Weather Conditions

In this paper, Bit Error rate and probability of outage are derived in closed form for plane wave mode over Gamma-Gamma free space optical channel under the influence of pointing errors and different weather conditions. The free-space optical system under study assumes deployment of intensity modulation / direct detection with on-off keying data formats. To evaluate the performance of the system using the derived expressions, two independent optimization algorithms were applied to find optimum system and channel parameters that optimize the performance of the two system metrics, i.e., bit error rate and probability of outage. The optimized system results were shown for different values of channel strength, weather conditions, optimum beamwidths and pointing error jitter variances. For each case, the optimized results are provided as a function of the transmitted power or average received power

Indications, outcome and complications of ureteroscopy, at Gezira Hospital for renal diseases and surgery, Sudan: a seven years ‘experience

Background: Ureteroscopy (rigid and flexible) with irrigating and working channels have expanded the capability of the urologist to diagnose and treat most abnormalities of the upper tracts.Objective: This study was conducted as a part of holistic auditing to the services provided by Gezira Hospital for Renal Disease and Surgery (GHRD&amp;S), and specifically to evaluate ureteroscopy done in GHRD&amp;S with emphasis on the indications, outcome and complications.Methods: Across-sectional- hospital-based study was adopted. All patients who underwent ureteroscopy since the inauguration of the hospital from 2005-2011 were included.Results: The total number of patients satisfying the inclusion criteria was 472 with a mean age of 40.6 years. Male to female ratio was 1.46:1. The mean hospital stay was 2.74 days.The commonest indication for ureteroscopy was ureteric stone amounting (74%) to a tangible share of ureteric stenting or removal as indication were found in (56.8%) . and therapeutic ureteroscopy for (92.3%). Ureteric stricture was not uncommon (24%). The success rate of therapeutic ureteroscopy was (93.7%) with definite correlation to the site of pathology been (91.75%), (92.3 %) and (87.5%) for the lower, mid and upper ureter respectively. The complications recorded were bleeding (3.3%), penetration (2.5 %), post-operative colic (13%) and infection (0.4%). Mortality rate was zeroConclusion: Because the experience of ureteroscopy in GHRD&amp;S was auspiced by regular training from the SIU the outcome is really comparable to the literature.Keywords: Ureteroscopy, Gezira Hospital for Renal Disease and Surgery, Wad Medani, Success and safet