Hidden Symmetry in Interacting-Quantum-Dot-Based Multiterminal Josephson Junctions.

We study a multiterminal Josephson junction based on an interacting quantum dot coupled to n superconducting BCS leads. Using an Anderson type model of a local level with an arbitrary on-site Coulomb repulsion, we uncover its surprising equivalence with an effective two-terminal junction with symmetric couplings to appropriately phase-biased leads. Regardless of the strength of the Coulomb interaction, this hidden symmetry enables us to apply well-established numerical and theoretical tools for exact evaluation of various physical quantities, and imposes strict relations among them. Focusing on three-terminal devices, we then demonstrate several phenomena such as the existence of the finite energy band crossings and superconducting transistor and diode effects, as well as current phase relation modulation.

Binocular Function in Adults before and after Strabismus Surgery.

PURPOSE: To evaluate the state of binocular vision, the amount and direction of the ocular deviation before and after strabismus surgery in adult patients and to monitor the occurrence of postoperative complications. METHODS: The retrospective study of 58 adult patients with selected types of strabismus who were surgically treated in the Eye Department of the Tomas Bata Regional Hospital in Zlín. We evaluated the amount and the degree of the primary ocular deviation and the binocular alignment before and after surgery,  as well as the state of binocular vision after surgery and the occurrence of postoperative complications. RESULTS: The average deviation in convergent strabismus before surgery was +23.46 degrees, after surgery +6.6 degrees, in divergent strabismus it was -21.5 degrees, after surgery -1.48 degrees, for vertical strabismus before surgery +12.5 degrees and +3.75 degrees after surgery and in paralytic strabismus +20 degrees before surgery and +3 degrees postoperatively. Preoperatively there was effectively no binocular vision in up to 63.9% of patients, superposition occurred in 31%, fusion in 5.1%. No patient had stereopsis before surgery. After surgery, superposition was present in 39.7%, fusion in 31% and stereopsis in 6.9% of patients. Only 22.4% of patients experienced no binocular vision after surgery. Of the selected 21 patients out of 58 with an observation period of at least 3 years, we observed an improvement or development of binocular vision functions after surgery in 12 patients and no improvement of binocular vision functions in 9 patients. In the first group, 58.3% had a stable deviation throughout the follow-up period. While in the second group the deviation was stable in only 33.3%. We can assume that the improvement in binocular vision function after strabismus surgery, leads to a greater longer-term stability of postoperative deviations. CONCLUSION: Strabismus surgery in adult patients is an effective and safe method, which is not only a cosmetic procedure used to adjust the position of the eyes, but also enables us to induce or improve the state of binocular vision functions.

[Acute Traumatic Intervertebral Disc Herniation]. / Akutní traumatická hernie intervertebrálního disku.

Acute traumatic intervertebral disc herniation of the thoracic spine is a rather rare injury with only a few reported cases to date. In this manuscript, we present a case of a 58-year-old male patient who sustained a car accident-related high-energy trauma, resulting in a disc herniation of the thoracic spine. Furthermore, we also discuss the possible implications of late diagnosis of such condition. The patient was initially referred from the Emergency Department as a case of head contusion with a left upper limb paresis. Due to only minimal bony trauma visible on the initial spine CT scan, the neurological deficit was attributed to the cranial trauma. The diagnosis of a traumatic disc herniation was therefore established only after the rapid onset of paraparesis, which gradually progressed into paraplegia, and a following spine MRI scan. Despite the subsequent urgent spinal decompression, the neurological functions of the lower limbs were not restored. This manuscript addresses the indications for performing MRI scans in polytrauma patients with a CT-verified spine trauma. Although it may be complicated to perform routine MRI scans in all such patients in daily practice, it can certainly help diagnose such injuries earlier and thus prevent potential permanent neurological damage to the patients. Key word: spine injury, traumatic disc herniation, thoracic spine, spine surgery.

Modern diagnostic approach to patients with abdominal aortic aneurysm.

INTRODUCTION: Abdominal aortic aneurysm (AAA) is a relatively frequent and serious condition in vascular surgery. The diagnostic and indication process and its treatment are driven by the guidelines which dictate an intervention when the maximum AAA diameter is more than 55 mm. Nevertheless, this approach is not fully sufficient in all AAA cases and thus we have been seeking to develop a modern diagnostic tool using computer modeling and vascular wall stress analysis. METHODS: The project has been ongoing in cooperation with engineers from VUT Brno (Brno University of Technology) and VŠB Ostrava (Technical University of Ostrava) for ten years. The design of the analytical tool was created during the first, experimental period of the project; this tool is able to assess vascular wall stress from regular CT scans using the finite element method. This primary model was gradually altered and its precision was increased considerably in the course of the years using data from mechanical and histological tests of AAA wall specimens harvested during open repairs. Additionally, other patient specific data are included in the analysis such as blood pressure, gender and material characteristics. RESULTS: The effectiveness of the method was evaluated in a pseudo-prospective study, showing clear superiority of the vascular wall stress analysis over the maximum diameter approach. The method was used in clinical practice for the first time during restrictions due to the COVID-19 pandemic; based on the analysis we were able to assess which AAA cases can be postponed and which had a high risk of rupture and an intervention was required despite the restrictions. The method achieved 100% sensitivity, and its specificity was also much better compared to the maximum diameter approach. CONCLUSION: The vascular wall stress analysis of AAA seems to be much more precise than the classic indication approach based only on the maximum diameter, and it can be used to determine the therapy based on patient specific parameters.

Endovenous ablation of varicose veins current status and overview of methods.

During the last two decades, superficial venous surgery has experienced an unprecedented boom. Traditional surgical procedures (crossectomy and stripping) are now being replaced to a greater or lesser extent by new less invasive endovenous methods. Our aim is to provide an up-todate review of all available endovenous techniques (laser, radiofrequency, steam, mechanochemical ablation and venous glue) describing the indications, the technique and mechanism of action, and the results. In experienced hands, all endovenous techniques are safe and effective, with long-term results comparable to conventional surgical procedures.

[Scanning Technique in Shoulder Ultrasonography]. / Sonografické vysetrení ramena.

This guide to ultrasound examination of the shoulder describes the basic scanning planes and contains corresponding high-resolution ultrasound images. The patient and probe positionings are explained in a simplified step-by-step manner using schematic drawings. This standard and simple examination technique seems to be an appropriate way to improve the learning curve of novice musculoskeletal sonographers. In this manuscript, an emphasis is placed on the rotator cuff, biceps tendon, subacromial-subdeltoid bursa, and joint recesses evaluation. This article also describes some common pitfalls to avoid when starting with shoulder ultrasonography (e.g. always determine the relevance of ultrasound findings in the context of clinical examination). Key words: tendons, bursa, synovial, shoulder, musculoskeletal, protocol, examination, ultrasound imaging, sonography, rotator cuff, acromioclavicular joint, shoulder impingement syndrome, learning curve.

[Scanning Technique in Elbow Ultrasonography]. / Sonografické vysetrení lokte.

This introduction to ultrasound evaluation of the elbow describes the basic scanning planes and contains corresponding high-resolution ultrasound images. The patient and probe positionings are explained in a simplified step-by-step manner using schematic drawings. This standard and simple examination technique seems to be an appropriate way to improve the learning curve of novice musculoskeletal sonographers. In this manuscript, an emphasis is placed on effusion detection, ulnar nerve imaging, and commonly injured tendons assessment. This article also describes some common pitfalls to avoid when starting with musculoskeletal ultrasonography (e.g. positioning issues, unsolicited artifacts). Key words: tendons, elbow tendinopathy, golfer's elbow, tennis elbow, musculoskeletal, protocol, ultrasound, common extensor tendon, common flexor tendon, ulnar nerve.

[Scanning Technique in Hip Ultrasonography]. / Sonografické vysetrení kycle.

This guide to ultrasound imaging of the hip describes the basic scanning planes and contains corresponding highresolution ultrasound images. The patient and probe positionings are explained in a simplified step-by-step manner using schematic drawings. This standard and simple examination technique seems to be an appropriate way to improve the learning curve of novice musculoskeletal sonographers. In this manuscript, an emphasis is put on hip effusion detection and on how to diagnose tendon and muscle injuries. Key words: tendons, hip tendinopathy, hip joint, athletic injuries, musculoskeletal, protocol, ultrasound, adductor tendon, trochanteric bursa, sciatic nerve.

[Scanning Technique in Wrist and Hand Ultrasonography]. / Sonografické vysetrení zápestí a ruky.

This guide to ultrasound examination of the wrist and hand describes the basic scanning planes and contains corresponding high-resolution ultrasound images. The patient and probe positionings are explained in a simplified step-by-step manner using schematic drawings. This standard and simple examination technique seems to be an appropriate way to improve the learning curve of novice musculoskeletal sonographers. In wrist section, an emphasis is placed on the carpal tunnel and extensor tendons evaluation. In the hand region, the scanning of the flexor pulley system and the flexor pollicis longus is described. Key words: hand, wrist joint, ultrasound, tendons, carpal tunnel syndrome, De Quervain disease, trigger finger disorder, hand injuries, musculoskeletal, protocol.

[Scanning Technique in Knee Ultrasonography]. / Sonografické vysetrení kolena.

This guide to ultrasound imaging of the knee describes the basic scanning planes and contains corresponding high-resolution ultrasound images. The patient and probe positionings are explained in a simplified step-by-step manner using schematic drawings. This standard and simple examination technique seems to be an appropriate way to improve the learning curve of novice musculoskeletal sonographers. In this manuscript, an emphasis is placed on Baker's cyst and knee effusion detection and on how to diagnose collateral ligament injuries. Key words: tendons, knee joint, tendinopathy, Baker's cyst, popliteal cyst, menisci, tibial, medial collateral ligament, musculoskeletal, protocol, ultrasound.

[Scanning Technique in Ankle nad Foot Ultrasonography]. / Sonografické vysetrení hlezna a nohy.

This guide to ultrasound imaging of the ankle and foot describes the basic scanning planes and contains corresponding high-resolution ultrasound images. The patient and probe positionings are explained in a simplified step-by-step manner using schematic drawings. This standard and simple examination technique seems to be an appropriate way to improve the learning curve of novice musculoskeletal sonographers. In this manuscript, an emphasis is placed on joint effusion detection, plantar fasciitis, Achilles tendinopathy, and ligamentous injuries around the ankle. Key words: tendons, ankle joint, tendinopathy, Achilles tendon, fasciitis, plantar, anterior talofibular ligament, musculoskeletal, protocol, ultrasound.

Effect of Tumor Size and p16 Status on Treatment Outcomes - Achievement of Complete Remission in Prospectively Followed Patients with Oropharyngeal Tumors.

BACKGROUND: Oropharyngeal squamous cell tumors associated with human papillomavirus infection (p16 positive tumors) have better prognosis than p16 negative tumors regardless of the more advanced stage of the disease. Tumor volume (GTVt+n) is generally an important factor affecting treatment results of ionizing radiation. The aim of this prospective non-randomized study is to evaluate the effect of tumor volume on the (chemo)radiation treatment results in a group of patients with p16 negative and p16 positive oropharyngeal tumors. PATIENTS AND METHODS: Patients with confirmed squamous cell tumor of the oropharynx of stages III and IV, according to the 7th version of the TNM (tumor-nodes-metastases) classification, were eligible for this study. The main exclusion criteria were palliative treatment, neoadjuvant chemotherapy or planned concomitant therapy with cetuximab. Patients were treated according to standardized protocols with curative intent. Primary tumor volume (GTVt) and involved nodes volume (GTVn) were obtained from radiotherapy planning system for further statistical analysis. The differences in tumor volumes between the groups according to p16 expression were assessed with subsequent testing of probability to achieve complete remission (CR) of the disease in both groups. RESULTS: In total, 49 patients - 84% men, median age 60.5 years, 25 (51%) patients p16 positive, 40 (82%) underwent concomitant chemoradiotherapy. Median of GTVt in the whole patients group is 40.2 ccm, GTVn 11.78 ccm and median volume of the whole tumor burden (GTVt+n) 70.21 ccm (range 11.05-249). Median of GTVn was greater in the p16 positive cohort (p = 0.041). In the entire group, the median time to reach CR was 91 days (95% CI 86-107 days) from the end of radiotherapy. In the group of p16 negative patients, 14 achieved CR (61%) out of 23 patients, in p16 positive group 20 (80%) out of 25 patients (p = 0.111). P16 negative patients had a longer time to CR (p = 0.196, HR 1.58, 95% CI 0.79-3.18). None of the independently assessed volumetric parameters of the tumor (GTVt, GTVn, GTVt+n) affected CR in the p16 positive patients group, while there was a significant impact of the whole tumor burden (GTVt+n) in the p16 negative cohort (median 58.1 ccm in CR patients vs. 101.9 ccm, p = 0.018). CONCLUSION: We have showed less GTVt+n dependence to achieve CR in p16 positive tumors in comparison with p16 negative tumors. Thus, p16 positive oropharyngeal squamous cell cancers should not be withdrawn from the curative treatment intent based on the greater GTVt+n. Key words oropharyngeal neoplasms - p16 status - treatment outcome - tumor burden - complete remission This work was supported by grant of the Ministry of Health of the Czech Republic AZV 15-31627A and by grant of the Ministry of Health of the Czech Republic - Conceptual development of a research organization (MMCI 00209805). The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers. Submitted: 2. 11. 2018 Accepted: 11. 11. 2018.

Impact of isotropic constitutive descriptions on the predicted peak wall stress in abdominal aortic aneurysms.

Biomechanics-based assessment of Abdominal Aortic Aneurysm (AAA) rupture risk has gained considerable scientific and clinical momentum. However, computation of peak wall stress (PWS) using state-of-the-art finite element models is time demanding. This study investigates which features of the constitutive description of AAA wall are decisive for achieving acceptable stress predictions in it. Influence of five different isotropic constitutive descriptions of AAA wall is tested; models reflect realistic non-linear, artificially stiff non-linear, or artificially stiff pseudo-linear constitutive descriptions of AAA wall. Influence of the AAA wall model is tested on idealized (n=4) and patient-specific (n=16) AAA geometries. Wall stress computations consider a (hypothetical) load-free configuration and include residual stresses homogenizing the stresses across the wall. Wall stress differences amongst the different descriptions were statistically analyzed. When the qualitatively similar non-linear response of the AAA wall with low initial stiffness and subsequent strain stiffening was taken into consideration, wall stress (and PWS) predictions did not change significantly. Keeping this non-linear feature when using an artificially stiff wall can save up to 30% of the computational time, without significant change in PWS. In contrast, a stiff pseudo-linear elastic model may underestimate the PWS and is not reliable for AAA wall stress computations.

[Endoscopic harvest of great saphenous vein for infrainguinal arterial bypass: summary of our initial experience]. / Pouzití metody endoskopického odberu velké safény v periferní infrainguinální cévní chirurgii - zhodnocení iniciálních zkuseností.

INTRODUCTION: This study was undertaken to determine the feasibility of endoscopic vein harvest (EVH) for infrainguinal arterial bypass surgery. We describe our initial experience and early results of bypasses done using this minimally invasive approach. METHOD: From April 2012 to March 2015, 16 patients underwent 16 femoropopliteal bypass operations with great saphenous vein (GSV) being harvested by endoscopic technique. The indication for intervention was critical limb ischemia (Rutherford category "5") in 7 patients (43.7%) and severe intermittent claudication (Rutherford category "3") in 9 patients (56.3%). There were 14 male (87.5%) and 2 female (12.5%) patients, with a mean age of 59.9 years. Selection of patients for EVH was based on clinical and duplex ultrasound appearance of GSV. Only patients with adequate GSV were considered for EVH. We collected data regarding patients demographics, history, clinical findings, operative procedures and postoperative recovery including complications. Patients were followed at 3, 6, 12, 18 and 24 months postoperatively and yearly thereafter. Patencies were analyzed by Kaplan-Meier method. Statistical analysis was performed using IBM SPSS Statistics 21.0 software (IBM Corp, Armonk, NY). RESULTS: Endoscopically harvested GSV was utilised for formation of proximal (10; 62.5%) or distal (6; 37.5%) femoropopliteal bypass. One patient underwent conversion to open harvest after endoscopic dissection of the vein. It occurred early in our experience. All other GSV harvests were accomplished endoscopically. 2 patients (12.5%) developed postoperative surgical site infection (SSI) Szilagyi gr. II (1 patient after successful EVH - location: groin; 1 patient after conversion of EVH to open vein harvest - location: groin and vein harvest incision). Mean follow-up was 10.2 months (range 0.3 to 27.0 months). At 1 and 2 years, primary patency was 82.0% and 82.0%, assisted primary patency was 93.8% and 93.8%, and secondary patency was 100.0% and 100.0%. At 1 and 2 years, amputation-free survival was 100.0% and 100.0%. No patient died within the study period (mortality 0.0%). CONCLUSIONS: Endoscopic harvest of GSV is a minimally invasive alternative to a standard open harvest of GSV. It is a feasible option for patients undergoing infrainguinal arterial bypass. In our early experience, patencies of EVH femoropopliteal bypasses are comparable to those achieved using traditional open vein harvest technique. Combination of endoscopic vein harvest with femoropopliteal bypass formation results in a low incidence of surgical site infections. KEY WORDS: endoscopic vein harvest - great saphenous vein - peripheral vascular surgery - femoropopliteal bypass - minimally invasive vascular surgery.

Perturbation theory of a superconducting 0 - π impurity quantum phase transition.

A single-level quantum dot with Coulomb repulsion attached to two superconducting leads is studied via the perturbation expansion in the interaction strength. We use the Nambu formalism and the standard many-body diagrammatic representation of the impurity Green functions to formulate the Matsubara self-consistent perturbation expansion. We show that at zero temperature second order of the expansion in its spin-symmetric version yields a nearly perfect agreement with the numerically exact calculations for the position of the 0 - π phase boundary at which the Andreev bound states reach the Fermi energy as well as for the values of single-particle quantities in the 0-phase. We present results for phase diagrams, level occupation, induced local superconducting gap, Josephson current, and energy of the Andreev bound states with the precision surpassing any (semi)analytical approaches employed thus far.

Perigraft seroma as a rare angiosurgical complication.

Perigraft seroma is quite a rare complication that may occur after implantation of Dacron or expanded polytetrafluoroethylene (ePTFE) vascular grafts. We report a case of a 54-year-old patient with perigraft seroma around an axillofemoral bypass (ePTFE graft). Definitive treatment involved the explantation of this extraanatomic bypass with perigraft seroma and the implantation of an aortobiiliac bypass using vascular prosthesis made of a different material. Based on published studies, therapeutic options for this complication are discussed. No guidelines or recommendations are available. In conclusion, the approach to perigraft seroma treatment remains strictly individual. Vascular graft replacement using grafts made of different material seems to be the best option in the case of recurring perigraft seroma, where less invasive procedures were not successful.

Evaluation of three purely polypropylene meshes of different pore sizes in an onlay position in a New Zealand white rabbit model.

BACKGROUND: The aim of the study was to evaluate the influence of the pore size of a polypropylene mesh on the shrinkage and elasticity of the mesh-tissue complex and the inflammatory reaction to the implant in an open onlay hernia repair. MATERIALS AND METHODS: Twenty-one 10 × 10 cm samples of polypropylene meshes of a different pore size (3.0 × 2.8 mm-PP3, 1.0 × 0.8 mm-PP1 and 0.6 × 0.5 mm-PP.5) were implanted in an onlay position in 21 New Zealand white rabbits. After 90 days of implantation the shrinkage, elasticity and foreign body reaction (FBR) were assessed. RESULTS: The shrinkage of PP3 was 30.6 ± 4.3 %, PP1 49.3 ± 2.9 % and PP.5 49.5 ± 2.6 %. The shrinkage of PP3 was significantly lower (PP3 × PP1 p = 0.007, PP3 × PP.5 p = 0.005), PP1 and PP.5 were similar. The elasticity was similar. The strength of FBR in mesh pores was similar. The width of foreign body granuloma layers at the mesh-tissue interface was significantly reduced with increasing pore size (inner: PP3 10.1 ± 1.2; PP1 12.5 ± 2.9; PP.5 17.4 ± 5.2 and outer: PP3 21.2 ± 2.5; PP1 30.6 ± 6.3; PP.5 60.4 ± 14.9). All differences between the widths of granuloma layers were statistically significant (p < 0.010). One animal (PP1) was excluded because of a mesh infection. CONCLUSIONS: Implantation of polypropylene mesh of a pore size of 3 mm in an onlay position is associated with a significant reduction of shrinkage in comparison to a 1 mm pore lightweight and 0.5 mm pore heavyweight mesh. A pore size increase to 3 mm is not sufficient for an improvement of mesh-tissue complex elasticity in comparison to a 1 mm pore lightweight and 0.5 mm heavyweight mesh. Polypropylene mesh with enlarged pores to 3 mm is associated with a similar strength of FBR in mesh pores and a reduced foreign body granuloma in comparison to a 1 mm pore lightweight and 0.5 mm pore heavyweight mesh.

Dose-response association between salivary cotinine levels and Mycobacterium tuberculosis infection.

SETTING: Tijuana, Mexico. OBJECTIVE: To describe the association between salivary cotinine levels and interferon-gamma (IFN-γ) release assay results. DESIGN: We conducted a cross-sectional study among injection drug users. Salivary cotinine levels were measured using NicAlert, a semi-quantitative dipstick assay. QuantiFERON©-TB Gold In-Tube (QFT-GIT) was used to determine Mycobacterium tuberculosis infection. RESULTS: Among 234 participants, the prevalence of QFT-GIT positivity for NicAlert cotinine categories 0 (non-smoking), 1 (second-hand smoke exposure or low-level smoking) and 26 (regular smoking) were respectively 42.1%, 46.4% and 65.2% (Ptrend 0.012). We found increasing trends in QFT-GIT positivity (Ptrend 0.003) and IFN-γ concentrations (Spearman's r 0.200, P 0.002) across cotinine levels 0 to 6. In multivariable log-binomial regression models adjusted for education, cotinine levels were not associated with QFT-GIT positivity when included as smoking categories (1 and 26 vs. 0), but were independently associated with QFT-GIT positivity when included as an ordinal variable (prevalence ratio 1.09 per 1 cotinine level, 95%CI 1.021.16). CONCLUSION: Our findings suggest that a dose-response relationship exists between tobacco smoke exposure and M. tuberculosis infection. Longitudinal studies that use biochemical measures for smoking status are needed to confirm our findings.

Remodeling of fetoplacental arteries in rats due to chronic hypoxia.

The increased fetoplacental vascular resistance due to chronic hypoxia cannot be explained by simple hypoxic vasoconstriction, as it sustains to some degree after recovery in normobaric environment. To verify a hypothesis that fetoplacental arteries undergo remodeling of their walls similar to remodeling of pulmonary arteries in hypoxic pulmonary hypertension, we used a model of the chronically hypoxic rat placenta. Han Wistar pregnant rats were exposed to 14-day hypoxia (10% of oxygen) during the 6th to 19th day of pregnancy. Chronic hypoxia elicited in both intraplacental (prelabyrinthine) and chorionic plate (insertion) arteries significant narrowing of their lumina. Irregular thickening of their adventitia due to an increase in collagen fibers as well as ground substance was observed; reticular fibers were fragmented. Because of remodeling of fetoplacental arteries, a model of chronically hypoxic rat placenta could simulate human preplacental hypoxia and consequent effects.

Understanding the Josephson current through a Kondo-correlated quantum dot.

We study the Josephson current 0-π transition of a quantum dot tuned to the Kondo regime. The physics can be quantitatively captured by the numerically exact continuous time quantum Monte Carlo method applied to the single-impurity Anderson model with Bardeen-Cooper-Schrieffer superconducting leads. For a comparison to an experiment, the tunnel couplings are determined by fitting the normal-state linear conductance. Excellent agreement for the dependence of the critical Josephson current on the level energy is achieved. For increased tunnel couplings the Kondo scale becomes comparable to the superconducting gap, and the regime of the strongest competition between superconductivity and Kondo correlations is reached; we predict the gate voltage dependence of the critical current in this regime.