Compact Precomputed Voxelized Shadows Construction on GPU

We consider the problem of producing high-quality shadows in real-time for 3D computer graphics software. In [1, 4] authors have proposed new data structure for object geometry representation by binary voxel grid. This binary data was packed to directed acyclic graph — traditional sparse voxel octree with merged identical subtrees. This approach has been extended to shadowing by voxelizing shadow volumes instead of object geometry [2, 3]. Obtained structure enables high-quality filtered shadows to be reconstructed for any point in the scene in real-time. In [1–4] authors have used CPU-based bottom-up algorithm that reduces sparse voxel octree to minimal directed acyclic graph. In the present paper we construct new parallel algorithm for such reduction that runs entirely on GPU

A 12 GHz satellite video receiver: Low noise, low cost prototype model for TV reception from broadcast satellites

A 12-channel synchronous phase lock video receiver consisting of an outdoor downconverter unit and an indoor demodulator unit was developed to provide both low noise performance and low cost in production quantities of 1000 units. The prototype receiver can be mass produced at a cost under $1540 without sacrificing system performance. The receiver also has the capability of selecting any of the twelve assigned satellite broadcast channels in the frequency range 11.7 to 12.2 GHz

Extravascular lung water assessed by transpulmonary single thermodilution and postmortem gravimetry in sheep

INTRODUCTION: Acute lung injury is associated with accumulation of extravascular lung water (EVLW). The aim of the present study was to compare two methods for quantification of EVLW: transpulmonary single thermodilution (EVLW(ST)) and postmortem gravimetric (EVLW(G)). METHODS: Eighteen instrumented and awake sheep were randomly assigned to one of three groups. All groups received Ringer's lactate (5 ml/kg per hour intravenously). To induce lung injury of different severities, sheep received Escherichia coli lipopolysaccharide 15 ng/kg per min intravenously for 6 hours (n = 7) or oleic acid 0.06 ml/kg intravenously over 30 min (n = 7). A third group (n = 4) was subjected to sham operation. Haemodynamic variables, including EVLW(ST), were measured using a PiCCOplus monitor (Pulsion Medical Systems, Munich, Germany), and the last measurement of EVLW(ST )was compared with EVLW(G). RESULTS: At the end of experiment, values for EVLW(ST )(mean ± standard error) were 8.9 ± 0.6, 11.8 ± 1.0 and 18.2 ± 0.9 ml/kg in the sham-operated, lipopolysaccharide and oleic acid groups, respectively (P < 0.05). The corresponding values for EVLWI(G )were 6.2 ± 0.3, 7.1 ± 0.6 and 11.8 ± 0.7 ml/kg (P < 0.05). Ranges of EVLWI(ST )and EVLWI(G )values were 7.5–21.0 and 4.9–14.5 ml/kg. Regression analysis between in vivo EVLW(ST )and postmortem EVLW(G )yielded the following relation: EVLW(ST )= 1.30 × EVLW(G )+ 2.32 (n = 18, r = 0.85, P < 0.0001). The mean bias ± 2 standard deviations between EVLW(ST )and EVLW(G )was 4.9 ± 5.1 ml/kg (P < 0.001). CONCLUSION: In sheep, EVLW determined using transpulmonary single thermodilution correlates closely with gravimetric measurements over a wide range of changes. However, transpulmonary single thermodilution overestimates EVLW as compared with postmortem gravimetry

Recombinant human activated protein C ameliorates oleic acid-induced lung injury in awake sheep

Introduction: Acute lung injury (ALI) may arise both after sepsis and non-septic inflammatory conditions and is often associated with the release of fatty acids, including oleic acid (OA). Infusion of OA has been used extensively to mimic ALI. Recent research has revealed that intravenously administered recombinant human activated protein C (rhAPC) is able to counteract ALI. Our aim was to find out whether rhAPC dampens OA-induced ALI in sheep. Methods: Twenty-two yearling sheep underwent instrumentation. After 2 days of recovery, animals were randomly assigned to one of three groups: (a) an OA+rhAPC group (n = 8) receiving OA 0.06 mL/kg infused over the course of 30 minutes in parallel with an intravenous infusion of rhAPC 24 mg/kg per hour over the course of 2 hours, (b) an OA group (n = 8) receiving OA as above, or (c) a sham-operated group (n = 6). After 2 hours, sheep were sacrificed. Hemodynamics was assessed by catheters in the pulmonary artery and the aorta, and extravascular lung water index (EVLWI) was determined with the single transpulmonary thermodilution technique. Gas exchange was evaluated at baseline and at cessation of the experiment. Data were analyzed by analysis of variance; a P value of less than 0.05 was regarded as statistically significant. Results: OA induced profound hypoxemia, increased right atrial and pulmonary artery pressures and EVLWI markedly, and decreased cardiac index. rhAPC counteracted the OA-induced changes in EVLWI and arterial oxygenation and reduced the OA-induced increments in right atrial and pulmonary artery pressures. Conclusions: In ovine OA-induced lung injury, rhAPC dampens the increase in pulmonary artery pressure and counteracts the development of lung edema and the derangement of arterial oxygenation

Rotator cuff tendon ruptures (literature review)

Rotator cuff injury is a common pathology: up to 20 % of the population over 45 years of age has ruptures of varying severity, and up to 40 % of these ruptures are large and massive. The gradual development of tendon degeneration and fatty degeneration of muscle tissue and the asymptomatic course of the disease often lead to late medical attention when secondary arthropathy of the shoulder joint develops. With age, the probability of having a rupture increases, reaching 51 % in people over  80  years of age. The main diagnostic tools are radiography and  magnetic resonance imaging of the shoulder joint combined with clinical examination. Conservative treatment for massive injuries is ineffective, and the risk of worsening rotator cuff tendinopathy to rupture reaches 54 %. There are three main directions in the surgery of rotator cuff injuries: tendon reconstruction or replacement of their defect with grafts; muscle transfer; shoulder arthroplasty. Subacromial balloon spacer and tenogenic patches are also used. Each of these methods has a number of disadvantages and limitations. The frequency of repeated ruptures of reconstructed tendons reaches 45 %. Muscle transfer is extremely demanding on the skill of the surgeon and is associated with high risks of neurological complications. Arthroplasty imposes a number of significant restrictions on the patient, reducing the  quality of life, and prosthesis components wear increases the risk of complications, especially during revision interventions. The use of the subacromial spacer is limited by its high cost and lack of  long-term follow-up of treatment outcomes. Tenogenic patches have not undergone clinical trials, being an experimental technique. There is no single approach to the treatment of massive rotator cuff ruptures. The results are contradictory, the advantages of each of the methods are balanced by their disadvantages, which provides a wide window of opportunity in the studying, optimizing classical and introducing new methods of treatment of this patholog

Latissimus Dorsi Transposition in Supraspinatus Tendon Retraction (Patte III) and Thomazeau Grade 3 Fatty Degeneration (Clinical Case)

Introduction. The proportion of injuries of the rotational cuff is from 65 to 84 % of all injuries of the shoulder joint. This pathology is more often registered in people over 60 years old. It is far from always that during initial visits, patients are given the correct diagnosis. Most patients are treated conservatively with short-term improvement or without dynamics. The main diagnostic method is an MRI of the shoulder joint, where we can see soft tissue structures. The proportion of massive rupture of the tendons of the supraspinatus muscle is 10-40 % of all ruptures of the rotator cuff.The more time passes from the moment of injury to surgical treatment, the more pronounced are the retraction and degenerative changes in tendons. A special category is occupied by patients with chronic rupture of the tendon of the supraspinatus muscle with a retraction of more than 5 cm (Patte grade III) and Thomazeau grade 3 fatty degeneration.In this category of patients, it is not possible to re-insert the tendons of the rotational cuff of the shoulder.Objective: to evaluate the clinical effectiveness of surgical treatment of a patient with retinal tendon retraction (Patte grade III) and Thomazeau grade 3 fatty degeneration.Materials and methods. The clinical case is presented: a man with a chronic total rupture of the tendon of the supraspinatus, infraspinatus muscle (Patte grade III) and Thomazeau grade 3 fatty degeneration. Secondary upper subluxation of the head of the humerus is revealed. The patient underwent surgical treatment: transposition of the latissimus dorsi muscle on the large tubercle of the humerus.Results. Six months after the operation, the patient restored the function of the upper limb, pain was stopped. Conclusion. Given the functional result, transposition of the latissimus dorsi tendon can be considered the technique of choice for inoperable tendon rupture of the supraspinatus muscle

Latissimus dorsi tendon transposition combined with shoulder joint proximal capsule plasty with peroneal longus tendon autograft in the treatment of patients with massive rotator cuff ruptures and proximal dislocation of the humerus head (clinical case)

The frequency of rotator cuff injuries in people over 45 years of age is 25.6–50 %, and  40  % of these injuries are massive. Shoulder rotator cuff injury causes disorders in biomechanics of the shoulder joint such as anterior-superior dislocation of the humeral head. Injury of the deltoid muscle combined with a massive rupture of the rotator cuff causes proximal dislocation of the humeral head during any active movement. In  the  treatment of these cases, surgical methods of treatment are used, such as transposition of the latissimus dorsi muscle, proximal capsule plasty, and reverse shoulder arthroplasty. We present a successful clinical case of treatment of a patient with chronic massive injury of the right shoulder joint rotator cuff tendons in combination with the injury of shoulder joint proximal capsule, dislocation of the right humerus head, and hypotrophy of the anterior portion of the deltoid muscle. We performed transposition of the latissimus dorsi tendon in combination with shoulder joint proximal capsule plasty with an autograft of the peroneal longus tendon. The check-up X-rays show that the dislocation of the right shoulder joint was eliminated. In the early postoperative period, the patient started physiotherapy exercises of the operated limb using abduction pillow. By the 7th day after surgery, the abduction of the operated limb reached 70°. The described surgical technique allows to restore congruence in the shoulder joint and the function of the injured limb in severe multiple injuries of the shoulder joint structures

Treatment of Patients with Rotator Cuff Injuries (Review of Literature)

The proportion of injuries to the rotator cuff of the shoulder occupies one of the leading places in the structure of injuries to the musculoskeletal system. The history of the study of this pathology began about five centuries ago and continues to the present day. However, attempts to introduce a generally accepted classification of injuries have not been crowned with success. With the development of scientific and technological progress, many methods of conservative and surgical treatment have appeared. Among the conservative methods of treatment aimed at reducing pain and improving the quality of life, injections of corticosteroids, hyaluronic acid, and autoplasma therapy are used. But, unfortunately, these treatment methods are not aimed at restoring the function of the shoulder joint. Surgical treatments for rotator cuff injuries are varied. This includes both the classic reinsertion of the damaged tendon and arthroscopic treatments. In case of massive ruptures, reconstructive plastic surgery is performed with the transfer of the tendons of the infraspinatus, small round or latissimus dorsi muscle, and autografts or allografts are also used. However, despite the large number of treatment methods, there are no clear algorithms for managing patients with this pathology, and the percentage of unsatisfactory treatment outcomes remains high

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