Calibration sources and filters of the soft x-ray spectrometer instrument on the Hitomi spacecraft

Accepted: 2017-10-0

Complicated Jejunal Diverticulitis: A Challenging Diagnosis and Difficult Therapy

Background/Aim: In contrast to diverticulosis of the colon, jejunal diverticulosis is a rare entity that often becomes clinically relevant only after exacerbations occur. The variety of symptoms and low incidence make this disease a difficult differential diagnosis. Patients and Methods: Data from all patients who were treated in our surgical department for complicated jejunal diverticulitis, that is, gastrointestinal hemorrhage or a diverticula perforation were collected prospectively over a 6-year period (January 2004 to January 2010) and analyzed retrospectively. Results: The median age among the 9 patients was 82 years (range: 54-87). Except for 2 cases (elective operation for a status postjejunal peridiverticulitis and a re-perforation of a diverticula in a patient s/p segment resection with free perforation), the diagnosis could only be confirmed with an exploratory laparotomy. Perforation was observed in 5 patients, one of which was a retroperitoneal perforation. The retroperitoneal perforation was associated with transanal hemorrhage. Hemodynamically relevant transanal hemorrhage requiring transfusion were the reason for an exploratory laparotomy in 2 further cases. In one patient, the hemorrhage was the result of a systemic vasculitis with resultant gastrointestinal involvement. A singular jejunal diverticulum caused an adhesive ileus in one patient. The extent of jejunal diverticulosis varied between a singular diverticulum to complete jejunal involvement. A tangential, transverse excision of the diverticulum was carried out in 3 patients. The indication for segment resection was made in the case of a perforation with associated peritonitis (n=4) as well as the presence of 5 or more diverticula (n=2). Histological analysis revealed chronic pandiverticulitis in all patients. Median operating time amounted to 142 minutes (range: 65-210) and the median in-hospital stay was 12 days (range: 5-45). Lethality was 0%. Major complications included secondary wound closure after s/p repeated lavage and bilateral pleural effusions in one case. Signs of malabsorption as the result of a short bowel syndrome were not observed. Minor complications included protracted intestinal atony in 2 cases and pneumonia in one case. Median follow-up was 6 months (range: 1-18). Conclusion: Complicated jejunal diverticulitis often remains elusive preoperatively due to its unspecific clinical presentation. A definitive diagnosis can often only be made intraoperatively. The resection of all diverticula and/or the complete diverticula-laden segment is the goal in chronic cases. The operative approach chosen (tangential, transverse excision vs segment resection) should be based on the extent of the jejunal diverticulosis as well as the intraoperative findings

The wide field monitor onboard the Chinese-European x-ray mission eXTP

The eXTP (enhanced X-ray Timing and Polarimetry) mission is a major project of the Chinese Academy of Sciences (CAS), with a large involvement of Europe. The scientific payload of eXTP includes four instruments: the SFA (Spectroscopy Focusing Array) and the PFA (Polarimetry Focusing Array) - led by China - the LAD (Large Area Detector) and the WFM (Wide Field Monitor) - led by Europe (Italy and Spain). They offer a unique simultaneous wide-band X-ray timing and polarimetry sensitivity. The WFM is a wide field X-ray monitor instrument in the 2-50 keV energy range, consisting of an array of six coded mask cameras with a field of view of 180ºx90ºat an angular resolution of 5 arcmin and 4 silicon drift detectors in each camera. Its unprecedented combination of large field of view and imaging down to 2 keV will allow eXTP to make important discoveries of the variable and transient X-ray sky and is essential in detecting transient black holes, that are part of the primary science goals of eXTP, so that they can be promptly followed up with other instruments on eXTP and elsewhere

The enhanced x-ray timing and polarimetry mission – eXTP: an update on its scientific cases, mission profile and development status

The enhanced x-ray timing and polarimetry mission (eXTP) is a flagship observatory for x-ray timing, spectroscopy and polarimetry developed by an international consortium. Thanks to its very large collecting area, good spectral resolution and unprecedented polarimetry capabilities, eXTP will explore the properties of matter and the propagation of light in the most extreme conditions found in the universe. eXTP will, in addition, be a powerful x-ray observatory. The mission will continuously monitor the x-ray sky, and will enable multi-wavelength and multi-messenger studies. The mission is currently in phase B, which will be completed in the middle of 2022