Impurity-induced smearing of the spin resonance peak in Fe-based superconductors

The spin resonance peak in the iron-based superconductors is observed in inelastic neutron scattering experiments and agrees well with predicted results for the extended s-wave ($s_\pm$) gap symmetry. On the basis of four-band and three-orbital tight binding models we study the effect of nonmagnetic disorder on the resonance peak. Spin susceptibility is calculated in the random phase approximation with the renormalization of the quasiparticle self-energy due to the impurity scattering in the static Born approximation. We find that the spin resonance becomes broader with the increase of disorder and its energy shifts to higher frequencies. For the same amount of disorder the spin response in the $s_\pm$ state is still distinct from that of the $s_{++}$ state.Comment: 4 pages, 2 figure

Measurement of tensor analyzing powers in deuteron photodisintegration

New accurate measurement of tensor analyzing powers T20, T21 and T22 in deuteron photodisintegration has been performed. Wide-aperture non-magnetic detectors allowed to cover broad kinematic ranges in a single setup: photon energy = 25 to 600 MeV, proton emission angle in CM = 24 to 48 deg. and 70 to 102 deg. New data provide a significant improvement of a few existing measurements. The angular dependency of the tensor asymmetries in deuteron photodisintegration is extracted for the first time.Comment: 4 pages, 5 figures, submitted to Phys. Rev. Let

Videolaparoscopic surgical treatment of strangulated paraesophageal hiatal hernia (clinical observation)

Relevance. Paraesophageal hiatal hernias are much less common than other types of diaphragmatic hernias. The risk of strangulation in this pathology is about 21 %. It is often very difficult to establish the correct diagnosis in time, because patients are admitted with an atypical clinic of acute cardiological or pulmonary pathology. Usually, the correct diagnosis is established only on the 4th day. Due to late diagnosis, necrosis and perforation of the strangulated organ occur, which causes high mortality; sometimes the correct diagnosis is established only at autopsy.Clinical observation. The patient was admitted to the surgical department on an emergency basis with complaints of intense pain in the lower chest and epigastric region, vomiting of eaten food. From the anamnesis it is known that about a year ago, periodic nausea and vomiting of food eaten began to bother. The last 12 hours before admission to the hospital, pain in the chest and epigastrium intensified, all eaten food came out with vomiting. X-ray diagnosed strangulated paraesophageal hernia of the esophageal opening of the diaphragm. During esophagogastroduodenoscopy it was impossible to pass into the distal parts of the stomach; hyperemia and petechial hemorrhages were detected in the zone of strangulation. Video-laparoscopic reduction of the hernial contents, resection of the hernial sac and anterior diaphragm crurorrhaphy were urgently performed. The early postoperative period was uneventful. The presented clinical observation indicates the promise of using video-endoscopic technologies for diagnosis and treatment of strangulated diaphragmatic hernias. The key to success is the timely establishment of the correct diagnosis. We consider it impractical to perform an antireflux intervention simultaneously in conditions of an acute inflammatory process

Characteristics and clinical significance of magnetic resonance imaging manifestations of cerebral small vessel disease in acute period of ischemic stroke

Aim. To characterize magnetic-resonance imaging manifestations of cerebral small vessel disease in patients in acute period of ischemic stroke and to study their clinical significance. Methods. 56 patients in acute period of ischemic stroke and 10 subjects without stroke and cognitive impairment were examined. Magnetic-resonance tomography of the brain was performed to all patients and healthy subjects to assess the quantity of lacunes, perivascular spaces, leukoaraiosis and cerebral microbleeds. Based on analysis of 4 neurovisual markers of cerebral small vessel disease, an integral scale was developed. The obtained results were evaluated in association with a wide spectrum of clinical data. Results. Patients in acute period of ischemic stroke are characterized by higher quantitative expression of certain markers of cerebral small vessel disease in comparison with healthy age-matched subjects. A correlation between neuroimaging markers of cerebral small vessel disease and patients` age, severity and etiology of the stroke was observed. Total expression of cerebral small vessel disease, assessed using the integral score turned out to be higher in the group of stroke than in healthy elderly persons. High rates of certain markers of cerebral small vessel disease and integral scale score are associated with low mobility of patients, neurological deficiency and dependence in daily activities on discharge. Conclusion. In patients in acute period of ischemic stroke, higher expression of certain markers of cerebral small vessel disease and their total evidence were revealed in comparison with healthy people; total indicator of cerebral small vessel disease expression is associated with neurological and functional outcome of acute period of stroke