Comment on `Strong Vortex Liquid Correlation' from Multiterminal Measurements on Untwinned YBa2_2Cu3_3O7−δ_{7-\delta} Single Crystals'

A.Rydh and \"O.Rapp [Phys. Rev. Lett. {\bf 86}, 1873 (2001).] claim that the vortex liquid in untwinned YBa$_2$Cu$_3$O$_{7-\delta}$ crystals is correlated above the melting transition, in striking contrast to previous work [D.L\'opez {\it et al.}, Phys. Rev. Lett. {\bf 76}, 4034 (1996).]. In this Comment we present new measurements using the same experimental technique on twinned and untwinned YBa$_2$Cu$_3$O$_{7-\delta}$ crystals with similar overall characteristics as those reported by Rydh and Rapp . The comparison of the vortex correlation response in both cases indicates that the central conclusion of their work is not correct. Our results reconfirm the work by L\'opez {\it et al.} and points on the origin of the misinterpretation in the work of Rydh and Rapp.Comment: comment on A.Rydh and \"O.Rapp, Phys. Rev. Lett. {\bf 86}, 1873 (2001). accepted in Phys. Rev. Let

Anomalous Proximity Effect in Underdoped YBaCuO Josephson Junctions

Josephson junctions were photogenerated in underdoped thin films of the YBa$_2$Cu$_3$O$_{6+x}$ family using a near-field scanning optical microscope. The observation of the Josephson effect for separations as large as 100 nm between two wires indicates the existence of an anomalously large proximity effect and show that the underdoped insulating material in the gap of the junction is readily perturbed into the superconducting state. The critical current of the junctions was found to be consistent with the conventional Josephson relationship. This result constrains the applicability of SO(5) theory to explain the phase diagram of high critical temperature superconductors.Comment: 11 pages, 4 figure

Design of Force Fields from Data at Finite Temperature

We investigate the problem of how to obtain the force field between atoms of an experimentally determined structure. We show how this problem can be efficiently solved, even at finite temperature, where the position of the atoms differs substantially from the ground state. We apply our method to systems modeling proteins and demonstrate that the correct potentials can be recovered even in the presence of thermal noise.Comment: 10 pages, 1 postcript figure, Late

Elastic-to-plastic crossover below the peak effect in the vortex solid of YBa2Cu3O7 single crystals

We report on transport and ac susceptibility studies below the peak effect in twinned YBa2Cu3O7 single crystals. We find that disorder generated at the peak effect can be partially inhibited by forcing vortices to move with an ac driving current. The vortex system can be additionally ordered below a well-defined temperature where elastic interactions between vortices overcome pinning-generated stress and a plastic to elastic crossover seems to occur. The combined effect of these two processes results in vortex structures with different mobilities that give place to history effects.Comment: 4 pages, 4 figures. Published in PRB Rapid Comm., February 1, 200

Strongly Enhanced Current Densities in Superconducting Coated Conductors of YBa2Cu3O7-x + BaZrO3

There are numerous potential applications for superconducting tapes, based on YBa2Cu3O7-x (YBCO) films coated onto metallic substrates. A long established goal of more than 15 years has been to understand the magnetic flux pinning mechanisms which allow films to maintain high current densities out to high magnetic fields. In fact, films carry 1-2 orders of magnitude higher current densities than any other form of the material. For this reason, the idea of further improving pinning has received little attention. Now that commercialisation of conductors is much closer, for both better performance and lower fabrication costs, an important goal is to achieve enhanced pinning in a practical way. In this work, we demonstrate a simple and industrially scaleable route which yields a 1.5 to 5-fold improvement in the in-field current densities of already-high-quality conductors

Observation of narrow baryon resonance decaying into pKs0pK^0_s in pA-interactions at 70GeV/c70 GeV/c with SVD-2 setup

SVD-2 experiment data have been analyzed to search for an exotic baryon state, the $\Theta^+$-baryon, in a $pK^0_s$ decay mode at $70 GeV/c$ on IHEP accelerator. The reaction $pA \to pK^0_s+X$ with a limited multiplicity was used in the analysis. The $pK^0_s$ invariant mass spectrum shows a resonant structure with $M=1526\pm3(stat.)\pm 3(syst.) MeV/c^2$ and $\Gamma < 24 MeV/c^2$. The statistical significance of this peak was estimated to be of $5.6 \sigma$. The mass and width of the resonance is compatible with the recently reported $\Theta^+$- baryon with positive strangeness which was predicted as an exotic pentaquark ($uudd\bar{s}$) baryon state. The total cross section for $\Theta^+$ production in pN-interactions for $X_F\ge 0$ was estimated to be $(30\div120) \mu b$ and no essential deviation from A-dependence for inelastic events $(\sim A^{0.7})$ was found.Comment: 8 pages, 7 figures, To be submitted to Yadernaya Fizika. v3-v5 - Some references added, minor typos correcte

Original Guide for Minimally Invasive Distal Osteotomy of the First Metatarsal Bone in the Treatment of Hallux Valgus

Background. Minimally invasive surgical interventions are widely used in trauma and orthopedic surgery. Both the surgical technique and the instruments applied are being improved, which contributes to better functional results of patients’ treatment. Aim of the study — to present a new guide tool for minimally invasive surgical correction of acquired hallux valgus. Guide description. A guide tool intended to be used in minimally invasive surgical interventions for hallux valgus (HV) correction has been developed. It consists of several interconnecting components: the distal bar, the intramedullary guide, the proximal bar, and the wire guide. These components are fixed to each other. At the same time, the distal bar, the proximal bar, and the wire guide are connected with the possibility of adjusting their mutual positioning. The design of the proposed device enables to guide the first guiding wire and to place the cannulated screw in an optimal position. The presented clinical case illustrates the successful application of the described device. The patient underwent minimally invasive distal corrective osteotomy for hallux valgus of medium severity. According to the preoperative X-rays, the first intermetatarsal angle and the first toe deviation angle were 13.5° and 25°, respectively. Six months after the surgery, they were 3° and 7°, respectively. The result of the corrective surgery was considered excellent. Conclusion. Application of the proposed guide tool decreases surgery duration, reduces soft tissue damage and minimizes radiation exposure of the surgeon and the patient

Dynamics and Radiation of Young Type-Ia Supernova Remnants: Important Physical Processes

We examine and analyze the physical processes that should be taken into account when modeling young type-Ia SNRs, with ages of several hundred years. It is shown, that energy losses in the metal-rich ejecta can be essential for remnants already at this stage of evolution. The influence of electron thermal conduction and the rate of the energy exchange between electrons and ions on the temperature distribution and the X-radiation from such remnants is studied. The data for Tycho SNR from the XMM-Newton X-ray telescope have been employed for the comparison of calculations with observations.Comment: 19 pages, 8 figure

Прогностическая ценность шкалы оценки трудной интубации в бариатрической хирургии

   The objective was to assess the predictive value of the risk scale for difficult intubation in obese patients.   Materials and methods. The object of the study was 110 patients (90 women and 20 men) operated on as planned in 2022. The mean age of the patients was 42 ± 11 years. The median body mass index (BMI) was 43.7 kg/m 2 (Q1–Q3: 37.9–49.1). All patients underwent a standard preoperative examination with the identification of the risk of difficult airways according to the intubation difficulty scale (IDS): mouth opening, neck mobility, mandibular protrusion, Mallampati class, sternomental and thyromental distances, and history of previous intubations were assessed.   Results. Difficult intubation (3–4 degrees according to Cormack–Lehane) were detected in 19 patients (17.3 %). ROC-analysis revealed the dependence of the probability of difficult intubation on the total points on the intubation difficulty scale. The area under the ROC curve was 0.809 ± 0.063 with 95 % CI: 0.685 – 0.932. The model was statistically significant (p &lt; 0.001). The cut-off point value for the total points on the intubation difficulty scale, which corresponded to the highest value of the Youden index, was 4. The sensitivity and specificity of the model were 100.0 % and 47.3 %, respectively. Significant differences (p &lt; 0.001) were found in the analysis of the risk of difficult intubation depending on the total points on the intubation difficulty scale. The most significant differences (p &lt; 0.001) were demonstrated by the mouth opening width and neck mobility. There were no differences (p = 0.547) when analyzing the history of difficult airways and nighttime snoring.   Conclusion. Overall, the intubation difficulty scale showed predictive value in terms of assessing the risk of difficult airways (p = 0.002, χ2 = 13.230). The most reliable indicators for predicting the risks of difficult intubation were mouth opening less than 4 cm (p &lt; 0.001, χ2 = 11.185) and head and neck flexion in the atlanto-occipital joint less than 90о (p &lt; 0.001, χ2 = 10.858). Assessment of thyromental and sternomental distances, mandibular protrusion ability, and Mallampati class also showed statistical significance. Prior history of difficult intubation and nighttime snoring showed no statistically significant risk in predicting difficult airways (p = 0.547, χ2 = 0.363).   Цель – оценить прогностическую ценность шкалы риска трудной интубации у больных ожирением.   Материалы и методы. Объектом исследования послужили 110 пациентов (90 женщин и 20 мужчин), оперированных в плановом порядке в 2022 г. Возраст пациентов – 42 ± 11 лет. Медиана индекса массы тела (ИМТ) составила 43,7 кг/м2 (Q1–Q3 : 37,9–49,1). Всем пациентам проводили стандартный предоперационный осмотр с выявлением риска трудных дыхательных путей по шкале оценки трудной интубации (ШОТИ): оценены открывание рта, подвижность шеи, способность к выдвижению нижней челюсти, класс по Маллампати, стерноментальная и тироментальная дистанции, а также анамнез предшествующих интубаций.   Результаты. Трудная интубация (3–4 степени по Cormack–Lehane) выявлена у 19 пациентов (17,3 %). ROC-анализ выявил зависимость вероятности трудной интубации от суммы баллов по шкале оценки трудной интубации (площадь под ROC-кривой 0,809 ± 0,063 с 95 % ДИ: 0,685–0,9320, p &lt; 0,001). Пороговое значение суммы баллов по ШОТИ в точке cut-off, которому соответствовало наивысшее значение индекса Юдена, составило 4. Чувствительность и специфичность модели составили 100,0 % и 47,3 %, соответственно. Установлены значимые различия (p &lt; 0,001) при анализе риска трудной интубации в зависимости от суммы баллов по ШОТИ. Наиболее достоверные различия (p &lt; 0,001) продемонстрировали показатели ширины открывания рта и подвижности шеи. Не выявлено различий (p = 0,547) при анализе анамнеза трудных дыхательных путей и ночного храпа.   Заключение. Шкала оценки трудной интубации продемонстрировала прогностическую ценность в отношении оценки рисков трудных дыхательных путей (р = 0,002, χ2 = 13,230). Наиболее достоверными показателями в отношении прогнозирования рисков трудной интубации оказались открывание рта менее 4 см (р &lt; 0,001, χ2 = 11,185) и сгибание головы и шеи в атланто-окципитальном сочленении менее 90о (р &lt; 0,001, χ2 = 10,858). Оценка тироментальной и стерноментальной дистанций, способности к выдвижению нижней челюсти и классу по Маллампати также показали статистическую значимость. Предшествующий анамнез трудной интубации и ночной храп не выявили статистически значимого риска в отношении прогнозирования трудных дыхательных путей (р = 0,547, χ2 = 0,363)