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We demonstrate long-range superconducting correlations in a several micrometer-long carbon nanotube encapsulated in a van der Waals stack between hBN and NbSe$_2$. We show that a substantial supercurrent flows through the nanotube section beneath the NbSe$_2$ crystal as well as through the 2 $\mu$m-long section not in contact with it. As expected for superconductors of nanoscopic cross section, the current-induced breakdown of superconductivity is characterized by resistance steps due to the nucleation of phase slip centers. All elements of our hybrid device are active building blocks of several recently proposed setups for realization of Majorana fermions in carbon nanotubes., Comment: 11 pages, 6 figures

Monolayer transition-metal dichalcogenides (TMDCs) show a wealth of exciton physics. Here, we report the existence of a new excitonic species, the high-lying exciton (HX), in single-layer WSe2 with an energy of ~3.4 eV, almost twice the band-edge A-exciton energy, with a linewidth as narrow as 5.8 meV. The HX is populated through momentum-selective optical excitation in the K-valleys and is identified in upconverted photoluminescence (UPL) in the UV spectral region. Strong electron-phonon coupling results in a cascaded phonon progression with equidistant peaks in the luminescence spectrum, resolvable to ninth order. Ab initio GW-BSE calculations with full electron-hole correlations explain HX formation and unmask the admixture of upper conduction-band states to this complex many-body excitation. These calculations suggest that the HX is comprised of electrons of negative mass. The coincidence of such high-lying excitonic species at around twice the energy of band-edge excitons rationalizes the excitonic quantum-interference phenomenon recently discovered in optical second-harmonic generation (SHG) and explains the efficient Auger-like annihilation of band-edge excitons.

We performed a monocenter cohort study to determine surgical revision and mortality after sustaining an initial and a non-simultaneous contralateral proximal femoral fracture. We identified all patients surgically treated for a contralateral femoral fracture between 2006 and 2015. Patient demographic characteristics and follow-up were identified by our electronic database; failed information regarding revision and mortality were obtained by telephone, as well as the evaluation of the mobility for all alive patients. The endpoint of the study was set for every patient at least 2 years postoperatively. Within a total of 2296 patients, we identified 250 patients (10.8%) treated for a contralateral fracture. The mean interval between the two occurrences was 5.2 years and the mean age at the time of contralateral fracture was 84.4 years. Almost every third fracture occurred later than 5 years after the initial fracture, and even every tenth fracture later than 10 years. More than 50% of the patients also had dementia at this time. The total surgical revision rate was 17.2% after initial, and 20.4% after contralateral fracture, but this difference was statistically not significant (p = 0.31). However, revisions for infection or hematoma were more than twice after contralateral fracture (p = 0.006). The 1-year mortality rate was 36%, and dementia (log rank p

Background: The proximal femoral fracture is one of the most common injuries in the elderly. Nevertheless, no results beyond the second year post surgery have been reported in the literature. Therefore, the purpose of this study was to evaluate any revision and mortality within 10 years follow-up as well as the walking ability of still alive patients. Methods: A total of 200 consecutive patients were included. A prospective database was first used to collect the demographic data. Exactly ten years after the surgery, a final evaluation was conducted by telephone for every patient. Any revision, any contralateral as well as other fractures and the date of death were recorded. For all patients who were still alive, the mobility score according to Parker was also surveyed. Results: The average age was 79.0 years (SD: 12.5); women were affected at higher numbers (73.5%). The total surgical revision rate was 17.5% (35/200), due in particular to hematoma (9x) or infection (7x). A surgical revision later than two years was only needed in three patients (1.5%). The risk of another fracture caused by a fall was 19% (38/200), most often a contralateral femoral fracture (22/200; 11%) that happened on average 51.9 months (1-97) after the initial surgery. The risk of a contralateral femoral fracture was 15.4% (22/143) in patients who survived the first year post surgery. The postoperative mortality was 1, 2, 5 and 10 years or 23.5%, 32.5%, 55% as well as 81.5%, respectively. An average Parker's mobility score of 6.3 points (0-9) was determined for the 37 patients (18.5%) who were still alive at the time of the follow-up. Conclusion: The long-term study showed that revision surgery was only required in 3/200 patients (1.5%) beyond the second year of that surgery. On the other hand, more than half of all patients had already passed away five years after the initial surgery. The exact incidence of a contralateral femoral fracture was 11.9%, climbing to 15.4% if the patient survived at least one year. Nearly every fifth patient experienced another fall resulting in a severe fracture requiring treatment during the long-term course. (c) 2018 Elsevier Ltd. All rights reserved.

BACKGROUND Due to demographic change, more proximal femoral fractures can be expected in the future. However, accurate growth rates as well as follow-up research extending more than 1 year postsurgery are still lacking. MATERIALS AND METHODS First, we defined inclusion and exclusion criteria for the retrospective cohort study. Based on these, we collected all surgical interventions conducted between 1 January 2006 and 31 December 2015. For a total of 2000 consecutive procedures, we retrieved and analysed a total of 12 variables influencing mortality. Data were retrieved from the prospectively established database; all patients still alive were contacted by phone, and missing data were collected. The endpoint of the study was consistently set for all patients at 2 years postsurgery. RESULTS The follow-up rate was 100%. Growth rate increased by 74.1% over a period of 10 years. Mean age of the total population was 79.4 years, and women were predominantly affected (71.7%). Surgical treatment was based on osteosynthesis procedures (57%) using DHS, PFN, or screws, as well as on arthroplasty (43%) performing total hip arthroplasty or implanting large-head prostheses. The revision rate was 14.5%, and mortality 2 years postsurgery was 32.4%. Through a multivariate analysis (Cox regression), the following seven influence factors showed statistically significant impact on mortality: age >82 years, male gender, CRP >10 mg/dl, haemoglobin

Introduction: There are increasing demands to perform surgery of hip fractures without delay. However, few studies have assessed the time to surgery in relation to outcome measurements. Methods: A total of 643 consecutive patients with a minimum age of 60 years underwent total hip arthroplasty (THA) for an intracapsular hip fracture. For this retrospective case series, demographic data and the outcome measurements—(1) any surgical revision, (2) implant failure, and (3) mortality—were documented from a prospective clinical database. The time from admission to surgery was also documented prospectively and then data were divided into 4 groups according to the time of surgery: (1) within 12 hours, (2) >12 to 24 hours, (3) >24 to 48 hours, and (4) later than >48 hours. The study end point was 2 years after surgery. Final evaluation was conducted for any missing data through a telephone interview. Results: The patients comprised 456 women (70.9%) and 187 men (29.1%) with a mean age of 80.2 years (range 60-104 years; standard deviation ±7.4). Descriptive data were without effect in all 4 groups. Time to surgery did not significantly influence revision for any reason ( P = .323), implant failure ( P = .521), and mortality ( P = .643). Cox regression analysis identified male sex ( P < .001; 95% confidence interval (CI), 1.27-2.44), American Society of Anesthesiologists score ≥3 ( P < .001; 95% CI, 2.12-21.59), C-reactive protein level >21 mg/L ( P < .018; 95% CI, 1.09-2.60), hemoglobin level Conclusion: Time to surgery had no effect on revision for any reason, implant failure, and mortality in patients undergoing THA for an intracapsular hip fracture.

Purpose: We investigated whether percutaneous suturing of Achilles tendon ruptures showed better results and superiority in terms of clinical outcomes when compared to open suturing. Methods: We conducted a case-control study. Between 2009 and 2014, we performed surgical revisions of closed acute Achilles tendon ruptures in our hospital in 146 patients, of which 71 patients (2012-2014) received percutaneous suturing using Dresden instruments, and 75 patients (2009-2012) underwent open suturing. After a minimum period of 1 year post surgery, we performed clinical follow-up in 25 patients of each of the groups using the AOFAS hind foot score and the SF-12 questionnaire. Furthermore, we implemented a clinical questionnaire with a reference population of 200 healthy individuals. Results: Mean age in the total population of 146 patients was 47 years (range 21 to 83 years) at the time of surgery. The duration of the surgical procedure with percutaneous suturing was significantly shorter (24 versus 43 minutes, p ollow-up, no significant differences between the two groups were observed in terms of descriptive parameters. Furthermore, ultrasound examinations of both follow-up populations did not show any significant difference. From a clinical perspective, the good to very good results achieved with open suturing (as measured with the AOFAS hind foot score and the SF-12 questionnaire) have not been significantly improved with percutaneous suturing. The additional use of a new clinical score (with the reference population) demonstrated good to very good consistency with the established scores. Conclusion: In our population, percutaneous Achilles tendon suturing showed significantly lower complication rates and significantly shorter procedure times when compared to open suturing. However, percutaneous suturing did not show clinical improvements of the good to very good results that were achieved with open suturing (as measured with the AOFAS back foot score and the SF-12 questionnaire). The implementation of a new and simple score for the clinical evaluation of Achilles tendon injuries resulted in good to very good consistency with the established questionnaires and, thus, offered a straightforward and rapid alternative when compared to the more elaborate scores.

Due to demographic change, more proximal femoral fractures can be expected in the future. However, accurate growth rates as well as follow-up research extending more than 1 year postsurgery are still lacking.First, we defined inclusion and exclusion criteria for the retrospective cohort study. Based on these, we collected all surgical interventions conducted between 1 January 2006 and 31 December 2015. For a total of 2000 consecutive procedures, we retrieved and analysed a total of 12 variables influencing mortality. Data were retrieved from the prospectively established database; all patients still alive were contacted by phone, and missing data were collected. The endpoint of the study was consistently set for all patients at 2 years postsurgery.The follow-up rate was 100%. Growth rate increased by 74.1% over a period of 10 years. Mean age of the total population was 79.4 years, and women were predominantly affected (71.7%). Surgical treatment was based on osteosynthesis procedures (57%) using DHS, PFN, or screws, as well as on arthroplasty (43%) performing total hip arthroplasty or implanting large-head prostheses. The revision rate was 14.5%, and mortality 2 years postsurgery was 32.4%. Through a multivariate analysis (Cox regression), the following seven influence factors showed statistically significant impact on mortality: age82 years, male gender, CRP 10 mg/dl, haemoglobin 12 g/dl, ASA 3 or 4, dementia, and postoperative infection-but not timing of surgery.The growth rate of proximal femoral fractures progressed more rapidly than expected. Through a multivariate analysis, a total of six intrinsic variables were verified, which influenced the mortality. The prevention of infection-as the only additional extrinsic factor in this study-represents a more important role than early surgical treatment.

Purpose: Total hip arthroplasty (THA) after failed osteosynthesis for proximal femoral fractures is associated with higher revision rates, particularly for dislocation. The purpose of this study was to report our results with THA after failed osteosynthesis within a treatment period of 10 years. Methods: A retrospective cohort study including 80 consecutive patients was conducted. After a minimum follow-up of 1 year, we evaluated revision for any cause including dislocation, outcome, and mortality. Results: We performed 48 THAs with standard components only and 32 THAs with revision implants. Routinely, a 36-mm femoral head was used, and trochanteric fixation was performed in one-third of the cases. Total revision rate for any cause was 21%, which included six infections, six periprosthetic fractures, and five hematomas. One hip dislocation was also treated. Treatment with uncemented revision stem revealed significantly higher number of revisions—compared to standard cemented or uncemented stem. The mortality rate after 1 year was 9%, and the mean Parker score at follow-up was 6.6 (range: 0−9). Conclusions: THA was associated with an increased surgical revision rate, but hip dislocation was documented only once. In most cases, a standard implant with a large 36-mm femoral head size was sufficient. Uncemented revision stem revealed significantly higher number of revisions—compared to standard cemented or uncemented stem. One-year mortality was lower than expected.

Low-temperature transport spectroscopy measurements on a quantum dot lithographically defined in a multiwall MoS2 nanotube are demonstrated. At T = 300 mK, clear Coulomb blockade is observed, with charging energies in the range of 1 meV. In single-electron tunneling, discrete conductance resonances are visible at finite bias. Additionally, a magnetic field perpendicular to the nanotube axis reveals clear indications of quantum state transitions, with effective g factors consistent with published theoretical predictions.

We present optical nanoantennas designed for applications that require processing temperatures larger than $800{\phantom{\rule{0.16em}{0ex}}}^{\ensuremath{\circ}}\mathrm{C}$. The antennas consist of arrays of Re/Pt bilayer strips fabricated with a lift-off-free technique on top of etched trenches. Reflectance measurements show a clear plasmonic resonance at approximately 670 nm for light polarized orthogonal to the strip axis. The functionality of the antennas is demonstrated by growing single-walled carbon nanotubes (CNTs) on top of the antenna arrays and measuring the corresponding Raman signal enhancement of selected CNTs. The results of the measurements are quantitatively discussed in light of numerical simulations which highlight the impact of the substrate.

Introduction Information is lacking regarding incidence rates, treatment regimens, and outcomes concerning peri-implant femoral fractures (PIF). Therefore, we performed a retrospective study to provide scientific data concerning incidence and outcome of PIF following osteosynthesis of proximal femoral fractures (PFF). Material and methods We retrospectively included all patients who received osteosynthesis for PFF between 2006 and 2015 and in whom PIF was confirmed postoperatively. All available patients with PIF were contacted minimum one year post-surgery. Results A total of 1314 osteosynthesis procedures were performed, of which 705 were proximal femoral nails (PFNs), 597 were dynamic hip screws (DHSs), and 12 were screws appliances only. During the same period, 18 PIFs (1.4%) were reported. However, PIF was 3.7 times higher within PFN when compared to DHS (15/705:2.1% versus 3/597:0.5%; odds ratio: 3.7). The following analysis also included 8 patients with PIF who were referred from other hospitals, resulting in a total of 26 patients. Mean patient age was 84.8 years (range, 57–95), with a predominance in female (23×) and in the left femur (19×). PIF occurred after an average of 23.6 months (range, 1–81) post-surgery. The fractures, most of which were spiral-shaped, were most commonly treated with locking plate osteosynthesis. The surgical revision rate was 7.7%, and the one-year mortality was 23.1%. At an average of 43.0 months (range, 12–100) post-surgery, it was possible to contact 18/26 patients (69.2%), and their mean Parker Mobility Score was 5.2 points (range 2–9). Conclusions Peri-implant femoral fracture is a rare incident within the old age traumatology of PFF. However, based on our small number of cases, it occurred within PFN much more frequently compared with DHS. Locking plate osteosynthesis has been shown to be effective and reliable. Surgical revision and mortality rates do not appear to be increased when compared to those with the initial treatment of proximal femoral fractures.

INTRODUCTION: To date, there is a lack of valid data with larger populations of patients in their 10th decade of life in the analyses of proximal femoral fractures. MATERIAL AND METHODS: The inclusion criteria focused on all proximal femoral fractures in patients 90-99 years of age who underwent surgical treatment between 2009 and 2012. After a period of at least 2 years post-surgery, a retrospective collection of empiric data, including the survival time and surgical revision rate, was performed. Missing data were collected per telephone interview. RESULTS: A total of 121 proximal femoral fractures in 117 patients in their 10th decade of life were treated. The mean age was 92.3 years. 61 fractures of the femoral neck received hemi- or total hip arthroplasty, while 60 pertrochanteric or subtrochanteric fractures were treated by osteosynthesis using proximal femoral nail (PFN) or dynamic hip screw (DHS). At the time of follow-up, 83/117 patients (71%) were already deceased. The mortality after 30 days, 6 months, 1 year and 2 years was 16%, 37%, and 43%, and 55%, respectively. A total of 22 surgical revisions (19%) were performed: 10 due to early infections, 8 due to haematomas, and 4 due to implant failures with a "cut out" of the femoral neck screw exclusively in DHS. The duration of surgery (with regard to surgical revision) and ASA classification (with regard to survival rate) were significant influence factors. Contralateral proximal femoral fractures were identified in 24/117 patients (20%), irrespective of study period. CONCLUSIONS: The proximal femoral fractures in the 10th decade of life are associated with high postoperative mortality within the first 6 months. Surgical revision due to complications did not result in a statistically significant reduction of the survival time. From the osteosynthetic perspective, the DHS was associated with a significantly higher "cut-out" rate compared to PFN procedure. With regard to the alloarthoplasty, there were no significant differences observed between hemi- and total hip arthroplasty. A contralateral femoral fractures was observed in 20% of the total study population, but peri-implant or periprosthetic femoral fractures have not been observed in any of the cases thus far. Language: en