Monoenergetic proton beams accelerated by a radiation pressure driven shock

High energy ion beams (> MeV) generated by intense laser pulses promise to be viable alternatives to conventional ion beam sources due to their unique properties such as high charge, low emittance, compactness and ease of beam delivery. Typically the acceleration is due to the rapid expansion of a laser heated solid foil, but this usually leads to ion beams with large energy spread. Until now, control of the energy spread has only been achieved at the expense of reduced charge and increased complexity. Radiation pressure acceleration (RPA) provides an alternative route to producing laser-driven monoenergetic ion beams. In this paper, we show the interaction of an intense infrared laser with a gaseous hydrogen target can produce proton spectra of small energy spread (~ 4%), and low background. The scaling of proton energy with the ratio of intensity over density (I/n) indicates that the acceleration is due to the shock generated by radiation-pressure driven hole-boring of the critical surface. These are the first high contrast mononenergetic beams that have been theorised from RPA, and makes them highly desirable for numerous ion beam applications

Gastrointestinal stromal tumors in elderly patients

To study the age-related characteristics of GISTs development in patients of older age group

Castleman disease. A rare clinical case of retroperitoneal tumor localization in an elderly patient

Castleman disease is an extremely rare benign disease of the lymphatic system with an estimated incidence of 1–9 cases per 1,000,000. Its etiology remains unknown; interleukin 6 (IL-6) plays an important role in pathogenesis. Castleman disease has two clinical forms: localized (up to 90 % of cases) with a favorable prognosis, treated predominantly by surgical method; generalized (up to 10 % of cases) with less favorable prognosis, treated by pharmacological therapy. The diagnosis is rarely established at the preoperative stage.The aim. To present a clinical case of diagnosis and treatment of Castleman tumor of a rare topical localization.Results. A 66-year-old patient was admitted at the Abdominal Oncology Department of the G.E. Ostroverkhov Kursk Oncology Scientific and Clinical Center.Diagnosis: Retroperitoneal mass on the right found at the preventive examination; no peripheral lymphadenopathy was detected on ultrasound and computed tomography (CT). After the examination, a preliminary diagnosis was made: Gastrointestinal stromal tumor (GIST) of the small intestine mesentery.  Based on the results of the case conference, the decision was taken to perform a surgery – laparoscopic removal of the tumor under endotracheal anesthesia. For surgical approach, a fan-shaped arrangement of ports was chosen. The surgery had no complications. Intraoperative blood loss was 50.0 ml. The total operating time was 98 minutes.According to the results of the histological study, the following diagnosis was made: Castleman disease, unicentric form, hyaline-vascular variant. En bloc surgery is the standard method for the treatment of localized forms of the Castleman disease. In all cases, long-term follow-up shows a long relapse-free period in almost all patients.During follow-up examinations (ultrasound of the abdominal cavity and retroperitoneal space, CT of the abdominal cavity with contrast enhancement, CT of the chest), no disease recurrence was detected during the year of observation.Castleman disease is a rare non-clonal lymphoproliferative disease of unknown etiology. A rare case of its retroperitoneal localization indicates that in cases with an uncertain nature of the peritoneal mass, Castleman disease should be included in the differential diagnostic search

Differential scanning calorimetry as a method for the control of vegetable oils

Differential scanning calorimetry (DSC) was used to study the thermophysical properties of oils of amaranth, corn, flax, sunflower, rapeseed, milk thistle, camelina, and pumpkin seed, liquid at room temperature. The characteristic thermal effects of these oils (temperatures of the maxima of endothermic peaks and their areas in the DSC thermograms) were determined. Endothermic peaks of different intensities on the melting curves of liquid vegetable oils in the ranges from -40 to -15°C, from-25 to -8°C, from -19 to +6°C, and from -10 to +4 °C as identification factors are discusse

Kaon pair production in proton-nucleus collisions at 2.83 GeV kinetic energy

The production of non-phi K+K- pairs by protons of 2.83 GeV kinetic energy on C, Cu, Ag, and Au targets has been investigated using the COSY-ANKE magnetic spectrometer. The K- momentum dependence of the differential cross section has been measured at small angles over the 0.2--0.9 GeV/c range. The comparison of the data with detailed model calculations indicates an attractive K- -nucleus potential of about -60 MeV at normal nuclear matter density at a mean momentum of 0.5 GeV/c. However, this approach has difficulty in reproducing the smallness of the observed cross sections at low K- momenta.Comment: 7 pages, 5 figures, 1 tabl

The production of K+K- pairs in proton-proton collisions at 2.83 GeV

Differential and total cross sections for the pp -> ppK+K- reaction have been measured at a proton beam energy of 2.83 GeV using the COSY-ANKE magnetic spectrometer. Detailed model descriptions fitted to a variety of one-dimensional distributions permit the separation of the pp -> pp phi cross section from that of non-phi production. The differential spectra show that higher partial waves represent the majority of the pp -> pp phi total cross section at an excess energy of 76 MeV, whose energy dependence would then seem to require some s-wave phi-p enhancement near threshold. The non-phi data can be described in terms of the combined effects of two-body final state interactions using the same effective scattering parameters determined from lower energy data.Comment: 12 pages, 12 figures, 3 table