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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. [ABSTRACT FROM AUTHOR]

Copyright of Česká a Slovenská Neurologie a Neurochirurgie is the property of Czech Medical Association of JE Purkyne and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In semiconductors, the spin degree of freedom is usually disregarded in the theoretical treatment of electron many-body effects such as band-gap renormalization and screening of the Coulomb enhancement factor. Nevertheless, as was observed experimentally in GaAs, not only the singleparticle phase-space filling but also many-body effects are spin sensitive. In this paper, we report on time- and polarization-resolved differential transmission pump-probe measurements in CdTe, which has the same zincblende crystal structure but different material parameters compared to that of GaAs. We show experimentally that at room temperature in CdTe—unlike in GaAs—the pumpinduced decrease of transmission due to the band-gap renormalization can even exceed the transmission increase due to the phase-space filling, which enables to measure directly the spinsensitivity of the band-gap renormalization. We also observed that the influence of the band-gap renormalization is more prominent at low temperatures. [ABSTRACT FROM AUTHOR]

Copyright of General Practitioner / Praktický Lékař is the property of Czech Medical Association of JE Purkyne and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aim: To evaluate the results of negative pressure wound therapy (NPWT) in the management of post-operative wound infections (Szilagyi's classification grade II and III) after elective arterial revascularization. Patients and methods: Retrospective analysis of patients' data. All patients who were treated between 2015 and 2018 using NPWT for wound infections after elective arterial procedures on lower extremities were included. Results: Between 2015 and 2018 a total of 13 patients have been treated using NPWT after elective infrainguinal arterial revascularization. There were nine men and four women of an average age of 72 years. Nine patients were treated for Szilagyi grade II infection (69.2%) and four patients for Szilagyi grade III infection (30.8%). In 11 cases there was an early postoperative infection (84.6%). The most common bacterial agent was Staphylococcus aureus. The minimum follow-up was 12 months. During the follow-up, the patency of arterial reconstructions was 92.3% and in 84.6% complete wound healing was achieved. The treatment success rate in the artificial graft patients' group was 88.9%. Conclusion: NPWT is an effective treatment of wound infections in patients after arterial lower extremity revascularization. The method shows promising results in the management of artificial graft infection as well. [ABSTRACT FROM AUTHOR]

Aim: The aim of the prospective study was to analyze the intensity of pain after surgery, perception of discomfort and post-operative pain, and the over-all life feelings related to the intervention treatment. Patients and methods: The sample comprised 76 patients who had been admitted and underwent a vascular surgical procedure of an abdominal aortic aneurysm /  iliac aneurysm (21.05%), femoral/ popliteal aneurysm (23.68%), aortoiliac occlusive dis-ease (3.95%), and infrainguinal occlusive dis-ease (51.32%). The patients evaluated the pain intensity, discomfort of the pain, and the over-all life feelings on a Visual Analogue Scale. The scale as-ses-sment was tested on 0– 7th day post-operatively through the Fisher's exact test, the chi-squared test was used for the gender, age, dia-gnosis, surgery type, anesthesiology risk, comorbidity, and complications related to the surgical intervention. A 5% level of significance was used for the testing. Results: When as-ses-s--ing the pain intensity, discomfort of pain, and the perception of over-all life feelings, there was find a significant dif-ference in relation with the type of the surgical intervention, dia-gnosis. Conclusion: Pain management is an important part of post-operative care. A systematic pain as-ses-sment is neces-sary to manage the pain appropriately. The highest intensity of pain was measured in patients after redo surgery, the worst discomfort and overall feeling were recorded in patients after abdominal aortic/pelvic artery aneurysm resection, while the highest intensity of pain and the worst overall feeling were measured in the first postoperative days with decreasing tendency over the time. [ABSTRACT FROM AUTHOR]

The role of ultrasound in clinical decision-making and interventions in airway management has expanded during the last decade. The ultrasound modality might be used in the emergency setting thanks to better knowledge of sonoanatomy of the upper and lower airways along with the growing skills in the usage of ultrasound as well as the technological advance. As examples, ultrasound might be used to localise the cricothyroid membrane during urgent coniotomy and even during real-time navigation of intubation when laryngoscopy has failed. It can be used for the assessment of the size of the endotracheal tube, the fasting status before intubation or induction of anaesthesia, it might be applied to predict difficul laryngoscopy in obese patients and to confirm endotracheal intubation. There are many other applications like, for example, ultrasound assistence during percutaneous tracheostomy or the performance of the superior laryngeal nerve block to facilitace awake intubation. Further investigations and more evidence-based data are, however, needed to establish a consensual role of ultrasound in this area. [ABSTRACT FROM AUTHOR]

BackgroundPlastic filters on cigarette butts are a widespread source of nonbiodegradable, toxic environmental waste. State and local legislation to ban the sale of single-use cigarettes may be considered to prevent this waste, but scientific evidence on the impact of switching smokers to unfiltered cigarettes on smoking behavior and toxicant exposures is needed to inform this policy. We have designed an open-label, randomized, 9-week, crossover clinical trial of adult filtered-cigarette smokers who switch to unfiltered cigarettes. ObjectiveOur objective is to understand the impact of switching smokers of filtered cigarettes to unfiltered cigarettes on smoking behavior and toxic exposures. MethodsThis trial involves a 1-week baseline period; a 2-week period of smoking filtered or unfiltered cigarettes, where groups are randomly assigned; a 3-week washout period; another 1-week baseline period; and a 2-week crossover period of smoking the opposite condition (ie, filtered or unfiltered cigarettes) for a sufficient sample size of 40 participants. We will determine changes in (1) observed topography (ie, puff count, interpuff interval, and puff volume) and cigarettes smoked per day, via butt counts and self-report, (2) expired carbon monoxide and excretion of urinary cotinine, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol, and volatile organic compounds, and (3) participants’ knowledge and attitudes toward unfiltered cigarettes, satisfaction with smoking, and intention to quit if they were not able to smoke filtered cigarettes. ResultsThis study was funded in June 2018 and approved by the relevant Institutional Review Boards in July 2018. This study has enrolled 37 participants as of October 2020. Data analysis is currently underway, and trial results are expected to be published in spring 2021. ConclusionsThis pilot proof-of-principle study will inform the design of a larger, future research project that can provide robust scientific evidence on our research question. Such a large study could inform possible state or local legislation to ban the sale of single-use filtered cigarettes in order to mitigate the environmental impact of discarded single-use plastic filters. Trial RegistrationClinicalTrials.gov NCT03749876; https://clinicaltrials.gov/ct2/show/NCT03749876 International Registered Report Identifier (IRRID)DERR1-10.2196/19603

Noise is a result of stochastic processes that originate from quantum or classical sources. Higher-order cumulants of the probability distribution underlying the stochastic events are believed to contain details that characterize the correlations within a given noise source and its interaction with the environment, but they are often difficult to measure. Here we report measurements of the transient cumulants ⟨⟨n[supm]⟩⟩ of the number n of passed charges to very high orders (up to m = 15) for electron transport through a quantum dot. For large m, the cumulants display striking oscillations as functions of measurement time with magnitudes that grow factonally with m. Using mathematical properties of high-order derivatives in the complex plane we show that the oscillations of the cumulants in fact constitute a universal phenomenon, appearing as functions of almost any parameter, including time in the transient regime. These ubiquitous oscillations and the factorial growth are system-independent and our theory provides a unified interpretation of previous theoretical studies of high-order cumulants as well as our new experimental data. [ABSTRACT FROM AUTHOR]

The long QT syndrome (LQTS) is a monogenic disorder characterized by prolongation of the QT interval on electrocardiogram and syncope or sudden death caused by polymorphic ventricular tachycardia (torsades de pointes). In general, mutations in cardiac ion channel genes ( KCNQ1, KCNH2, SCN5A, KCNE1, KCNE2) have been identified as a cause for LQTS. About 50-60 % of LQTS patients have an identifiable LQTS causing mutation in one of mentioned genes. In a group of 12 LQTS patients with no identified mutations in these genes we have tested a hypothesis that other candidate genes could be involved in LQTS pathophysiology. SCN1B and KCND3 genes encode ion channel proteins, ANK2 gene encodes cytoskeletal protein interacting with ion channels. To screen coding regions of genes SCN1B, KCND3, and 10 exons of ANK2 following methods were used: PCR, SSCP, and DNA sequencing. Five polymorphisms were found in screened candidate genes, 2 polymorphisms in KCND3 and 3 in SCN1B. None of found polymorphisms has coding effect nor is located close to splice sites or has any similarity to known splicing enhancer motifs. Polymorphism G246T in SCN1B is a novel one. No mutation directly causing LQTS was found. Molecular mechanism of LQTS genesis in these patients remains unclear. [ABSTRACT FROM AUTHOR]

We study spectral properties of a quantum dot attached to two superconductors with nonzero phase difference. The system is described as a single-impurity Anderson model coupled to BCS superconducting leads. We utilize diagrammatic perturbation expansion in the Coulomb interaction to capture relevant physical phenomena, particularly the effect of the Coulomb interaction on the Andreev bound states present in the electronic spectrum. Results of the Hartree-Fock and the random phase approximations at zero temperature are presented. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Self-consistent perturbation expansion up to the second order in the interaction strength is used to study a single-level quantum dot with local Coulomb repulsion attached asymmetrically to two generally different superconducting leads. At zero temperature and a wide range of other parameters, the spin-symmetric version of the expansion yields excellent results for the position of the 0-π impurity quantum phase transition boundary and Josephson current together with the energy of Andreev bound states in the 0 phase as confirmed by numerical calculations using the numerical renormalization group method. We analytically prove that the method is charge conserving as well as thermodynamically consistent. Explicit formulas for the position of the 0-n phase boundary are presented for the Hartree-Fock approximation as well as for its variant called generalized atomic limit. It is shown that the generalized atomic limit can be used as a quick estimate for the position of the phase boundary at half-filling in a broad range of parameters. We apply our second-order perturbation method to the interpretation of the existing experimental data on the phase boundary with very satisfactory outcome, suggesting that the so-far employed heavy numerical tools such as numerical renormalization group and/or quantum Monte Carlo are not necessary in a class of generic situations and can be safely replaced by a perturbative approach. [ABSTRACT FROM AUTHOR]

We study the subgap spectrum of the interacting single-level quantum dot coupled between two superconducting reservoirs, forming the Josephson-type circuit, and additionally hybridized with a metallic normal lead. This system allows for the phase-tunable interplay between the correlation effects and the proximity-induced electron pairing resulting in the singlet-doublet (0-π) crossover and the phase-dependent Kondo effect. We investigate the spectral function, induced local pairing, Josephson supercurrent, and Andreev conductance in a wide range of system parameters by the numerically exact numerical renormalization group and quantum Monte Carlo calculations along with perturbative treatments in terms of the Coulomb repulsion and the hybridization term. Our results address especially the correlation effects reflected in dependencies of various quantities on the local Coulomb interaction strength as well as on the coupling to the normal lead. We quantitatively establish the phase-dependent Kondo temperature logTK(ϕ)∝cos²(ϕ/2) and show that it can be read off from the half-width of the zero-bias enhancement in the Andreev conductance in the doublet phase, which can be experimentally measured by the tunneling spectroscopy. [ABSTRACT FROM AUTHOR]

We investigate experimentally the retrapping of the phase in a φ Josephson junction upon return of the junction to the zero-voltage state. Since the Josephson energy profile U0(ψ) in φ JJ is a 2π periodic double-well potential with minima at ψ=±φmod2π, the question is at which of the two minima -φ or +φ the phase will be trapped upon return from a finite voltage state during quasistatic decrease of the bias current (tilt of the potential). By measuring the relative population of two peaks in escape histograms, we determine the probability of phase trapping in the ±φ wells for different temperatures. Our experimental results agree qualitatively with theoretical predictions. In particular, we observe an onset of the butterfly effect with an oscillating probability of trapping. Unexpectedly, this probability saturates at a value different from 50% at low temperatures. [ABSTRACT FROM AUTHOR]