1,735 research outputs found
On the Fermionic Frequencies of Circular Strings
We revisit the semiclassical computation of the fluctuation spectrum around
different circular string solutions in AdS_5xS^5 and AdS_4xCP^3, starting from
the Green-Schwarz action. It has been known that the results for these
frequencies obtained from the algebraic curve and from the worldsheet
computations sometimes do not agree. In particular, different methods give
different results for the half-integer shifts in the mode numbers of the
frequencies. We find that these discrepancies can be removed if one carefully
takes into account the transition matrices in the spin bundle over the target
space.Comment: 13 pages, 1 figur
Remote results of treatment of patients with Monteggia injuries by transosseous osteosynthesis
The research is based on the analysis of treatment of 30 patients (during 2002-2010 years) with. Monteggia injuries by transosseous osteosynthesis. The aim. of the work was to show opportunities of transosseous osteosynthesis as mini-invasive method that allows to restore anatomical structures of injured segment by closed method. Separate fixation of radial and ulnar bones used in the work allowed to remove fixator from the radial bone without losing rigidity of fixation of ulnar bone and. to provide the opportunity of earlier development of rotation. At the estimation of effectiveness of treatment we considered functional activity of injured upper extremity in addition to the result of clinical and. radiologic examination of the patient. The accent was made on the typical mistakes at the treatment of these patients. Study of outcomes of treatment showed that 13 patients (86,6 %) had. usual degree of social integration in 6 months, 2 patients (13,4 %) had. slight limitations of social life. In a year all patients were considered socially integrated
Stereoelectronic effects in RNase-catalysed reactions of dinucleoside phosphate cleavage
AbstractThe rate at which dinucleoside phosphates are cleaved by RNases is supposed to be determined by the mole fraction of enzyme-substrate complexes in which the phosphodiester moiety of a dinucleoside phosphate has a highly reactive conformation. The mole fraction of such complexes for a particular RNase depends on the nature of a nucleoside at the O5'-end of the phosphodiester bond. Experimental data are presented to support this hypothesis
Comparative Determination of the Mechanical Strength of a Transplant from a Tendon of a Semitendinosus Muscle for Plastic Surgery of the Anterior Cruciate Ligament Prepared in Various Ways (Experimental Study)
According to modern literature, a sufficient number of studies have been carried out to determine the mechanical strength of transplants from the tendon of the semitendinous and gracilis muscles, the autologous ligament of the patella, the broad fascia, peroneus longus tendon, each of which has unique characteristics, but at present, transplants prepared by original (new) methods are understudied.In the period from November 5 to December 17,2018 we conducted an experimental study to determine the mechanical strength of a transplant from a tendon of a semitendinosus muscle taken from cadaveric material. The transplants were prepared by original and well-known (Graft-Link technique) methods.The experimental study was approved by the Ethics committee of Irkutsk Scientific Center of Surgery and Traumatology. The material for the study was prepared on the basis of the Irkutsk Regional Bureau of Forensic Medical Examination.After sampling the cadaveric material being studied, the main stages of the experimental study were carried out at the materials resistance department of the Irkutsk State Technical University. Studies of the mechanical properties of the transplant were carried out on a Shimadzu testing machine registered in the State Register of Measuring Instruments and approved for use in the Russian Federation.As a result of the study, we obtained the following data. The mechanical strength of the graft obtained from the tendon of the semitendinosus muscle in an original way is on average 607.8 ± 101.2 N/mm. The mechanical strength of the graft obtained from the tendon of the semitendinosus muscle in a traditional manner (Graft-Link technique) is on average 351.8 ± 133.0 N/ mm
Estimation of the effectiveness of surgical treatment of patients with old rupture of heel tendon with short plaster splint immobilization
Heel tendon injuries is the most common trauma of tendomuscular apparatus. Old ruptures of heel tendon occur in 58 % of cases in humans. The aim of the research was to estimate the effectiveness of treatment of the patients with old ruptures of heel tendon with Myerson type III defects who had tendon reconstruction on Chernavsky and short plaster splint immobilization of lower extremity for 4 weeks. We operated 10 patients using reconstruction on Chernavsky in our clinic from 2012 to 2014 (average age - 47,6 ± 12,0 years, 8 males and 2 females). All patients had old ruptures of heel tendon. Average time from the moment of trauma till the operation was 112,6 ± 80,4 days. Diastasis between the ends of tendon was 5,8 ± 0,7 cm that corresponds to Myerson type 111. Average term of staying at hospital was 10 ± 2 days. We didn't register any complications in postoperative period. Term of plaster immobilization of the operated extremity was 4 weeks. AOFAS score was 34,2 ± 6,8 points at the control examination in 1,5 months that corresponds to bad functional result. We registered good functional results (88,6 ± 3,5 points) in 3 months. 1n 6 months, functional results were 95,9 ± 1,6 points. 1n 12 months after the operation average score was 97,9 ± 2,1 points that corresponds to excellent functional result. Using heel tendon reconstruction on Chernavsky at the Myerson type 111 defects in combination with short plaster immobilization and early activization of patients allows to decrease term of rehabilitation of patients after the operation
A Statistical Study of Resistive Switching Parameters in Au/Ta/ZrO2(Y)/Ta2O5/TiN/Ti Memristive Devices
The authors acknowledge the ConsejerĂa de Conocimiento, InvestigaciĂłn y
Universidad, Junta de AndalucĂa (Spain), European Regional Development
Fund (ERDF) under projects A-TIC-117-UGR18, B-TIC-624-UGR20, and
IE2017-5414. Support from the Government of the Russian Federation
under Megagrant Program (agreement no. 074-02-2018-330 (2)) and
the Ministry of Science and Higher Education of the Russian
Federation under “Priority-2030” Academic Excellence Program of the
Lobachevsky State University of Nizhny Novgorod (N-466-99_2021-
2023) is also acknowledged. Memristive devices were designed in the
frame of the scientific program of the National Center for Physics and
Mathematics (project “Artificial intelligence and big data in technical,
industrial, natural and social systems”).Variability is an inherent property of memristive devices based on the switching
of resistance in a simple metal–oxide–metal structure compatible with the
standard complementary metal–oxide–semiconductor fabrication process. For
each specific structure, the variability should be measured and assessed as both
the negative and positive factors for different applications of memristive devices.
In this report, it is shown how this variability can be extracted and analyzed for
such main parameters of resistive switching as the set and reset voltages/cur-
rents and how it depends on the methodology used and experimental conditions.
The obtained results should be taken into account in the design and predictive
simulation of memristive devices and circuits.ConsejerĂa de Conocimiento, InvestigaciĂłn y Universidad, Junta de AndalucĂa (Spain), European Regional Development Fund (ERDF) under projects A-TIC-117-UGR18, B-TIC-624-UGR20, and IE2017-5414Government of the Russian Federation under Megagrant Program (agreement no. 074-02-2018-330 (2))Ministry of Science and Higher Education of the Russian Federation under “Priority-2030” Academic Excellence Program of the Lobachevsky State University of Nizhny Novgorod (N-466-99_2021- 2023
Activity of the right cardiac ventricle and metabolism in healthy persons during an orthostatic test after short term immobilization
A 15 minute orthostatic test was performed on healthy male volunteers under conditions of catheterization of the right ventricle of the heart and the radial (or brachial) artery before and after 5 day bedrest in an antiorthostatic position of the body (with the foot of the bed raised 4.5 degrees). The change to a vertical position after immobilization was attended by a more marked increase in the rate of cardiac contractions, an increase of max dp/dt pressure in the right ventricle, and a decrease of cardiac and stroke indices. The decrease of the cardiac index was compensated for, to a certain measure, by a further increase in the extraction and utilization of O2 by the tissues. The arterial blood pH did not change essentially, while the decrease in pCO2 and content of standard bicarbonate was more marked
Single and Double Bundle Arthroscopic Reconstruction of Anterior Cruciate Ligament (Review of Literature)
Researches performed in the past 20 years show the necessity of the restoration of anatomic position of anterior cruciate ligament as the main stabilizing structure of the joint in combination with the restoration of other injured elements and correction of deformities, which affect the outcomes of the treatment.Complexity of the restoration of anatomic position of torn anterior cruciate ligament is caused by its wide area of contact in combination with relatively small sectional area through the joint cavity. More detailed study of topographic anatomy of anterior cruciate ligament allowed the researchers to explain this phenomenon, which pushed them closer to the solution of the problem.Systemic anatomy of anterior cruciate ligament include two bundles - anteromedial bundle and posterolateral bundle. Double bundle plasty of anterior cruciate ligament restored anatomy to its nearly normal condition, but single bundle plasty is used much more often because of its simpler technique. However, the researchers still cannot reach a consensus in the choosing of single or double beam plasty at the restoration of anterior cruciate ligament
EXPERIENCE IN THE TREATMENT OF THE FALSE JOINT OF THE DIAPHYSIS OF THE RADIAL BONE COMBINED WITH A MAJOR DEFECT IN THE ULNAR DIAPHYSIS (CASE FROM PRACTICE)
This article presents the experience of surgical treatment of rare pathology of the upper limb – pseudoarthrosis of the middle third of the diaphysis of the radius, defect pseudoarthrosis of the upper and middle third of the ulnar diaphysis. The definition and compilation of an accurate model and treatment tactics are critical to restoring the anatomy and function of the injured upper limb. The rarity of this case was the size of the ulna defect, which was up to 4.0 cm, the scarring and cicatricial changes in the soft tissues and muscles of the right forearm, due to the severity of the injury and the multitude of surgical interventions on the right forearm. The chosen treatment tactics consisted of several successive stages: resection of the zone of false joint of the right radial bone, combined transosseous osteosynthesis of the right radius bone, resection of the false elbow joint of the right ulna with replacement of the defect with autograft from the lower third of the fibula, combined strained osteosynthesis and transosseous osteosynthesis by external fixation apparatus with rod configuration of the right ulna. The results of surgical treatment of false joints depend on the determination of the correct indications for a certain type of surgical intervention and the competent implementation of the planned treatment plan. The chosen treatment tactics allowed us to successfully restore the anatomy and function of the damaged segment, thus rehabilitating the patient
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