Monolithic high contrast grating on GaSb/AlAsSb based epitaxial structures for mid-infrared wavelength applications.

We demonstrate monolithic high contrast gratings (MHCG) based on GaSb/AlAs0.08Sb0.92 epitaxial structures with sub-wavelength gratings enabling high reflection of unpolarized mid-infrared radiation at the wavelength range from 2.5 to 5 µm. We study the reflectivity wavelength dependence of MHCGs with ridge widths ranging from 220 to 984 nm and fixed 2.6 µm grating period and demonstrate that peak reflectivity of above 0.7 can be shifted from 3.0 to 4.3 µm for ridge widths from 220 to 984 nm, respectively. Maximum reflectivity of up to 0.9 at 4 µm can be achieved. The experiments are in good agreement with numerical simulations, confirming high process flexibility in terms of peak reflectivity and wavelength selection. MHCGs have hitherto been regarded as mirrors enabling high reflection of selected light polarization. With this work, we show that thoughtfully designed MHCG yields high reflectivity for both orthogonal polarizations simultaneously. Our experiment demonstrates that MHCGs are promising candidates to replace conventional mirrors like distributed Bragg reflectors to realize resonator based optical and optoelectronic devices such as resonant cavity enhanced light emitting diodes and resonant cavity enhanced photodetectors in the mid-infrared spectral region, for which epitaxial growth of distributed Bragg reflectors is challenging.

Cost-effectiveness of stress CTP versus CTA in detecting obstructive CAD or in-stent restenosis in stented patients.

OBJECTIVES: The aim of this retrospective study was to determine cost-effectiveness of stress myocardial CT perfusion (CTP), coronary CT angiography (CTA), and the combination of both in suspected obstructive coronary artery disease (CAD) or in-stent restenosis (ISR) in patients with previous coronary stent implantation. METHODS: A decision model based on Markov simulations estimated lifetime costs and quality-adjusted life years (QALYs) associated with CTA, CTP, and CTA + CTP. Model input parameters were obtained from published literature. Probabilistic sensitivity analysis was performed to evaluate overall model uncertainty. A single-variable deterministic sensitivity analysis evaluated the sensitivity of the results to plausible variations in model inputs. Cost-effectiveness was assessed based on a cost-effectiveness threshold of $100,000 per QALY. RESULTS: In the base-case scenario with willingness to pay of $100,000 per QALY, CTA resulted in total costs of $47,013.87 and an expected effectiveness of 6.84 QALYs, whereas CTP resulted in total costs of $46,758.83 with 6.93 QALYs. CTA + CTP reached costs of $47,455.63 with 6.85 QALYs. Therefore, strategies CTA and CTA + CTP were dominated by CTP in the base-case scenario. Deterministic sensitivity analysis demonstrated robustness of the model to variations of diagnostic efficacy parameters and costs in a broad range. CTP was cost-effective in the majority of iterations in the probabilistic sensitivity analysis as compared with CTA. CONCLUSIONS: CTP is cost-effective for the detection of obstructive CAD or ISR in patients with previous stenting and therefore should be considered a feasible approach in daily clinical practice. KEY POINTS: • CTP provides added diagnostic value in patients with previous coronary stents. • CTP is a cost-effective method for the detection of obstructive CAD or ISR in patients with previous stenting.

First-in-human study demonstrating the safety and clinical efficacy of novel anti-IL-17A monoclonal antibody CJM112 in moderate to severe plaque psoriasis.

BACKGROUND AND OBJECTIVE: Anti-IL-17A IgG/κ monoclonal antibody CJM112 binds both IL-17A and IL-17AF. The purpose of this First-in-Human study was to assess CJM112 effects on safety and efficacy in patients with moderate to severe plaque psoriasis. METHODS: This study had two parts: single ascending doses of 5-450 mg subcutaneous (s.c.) CJM112 (SAD) and multi-dose parallel groups of CJM112 15 mg, 50 mg and 150 mg s.c. low frequency or high frequency (MD). SAD/MD were double-blind, randomized and placebo-controlled; MD also included a secukinumab 150 mg s.c. arm as an active comparator. Patients 18-65 years with moderate to severe psoriasis were included in this study. The efficacy outcome was the change in Psoriasis Area Severity Index (PASI) from baseline to Week 4 in the SAD part of the study, and from baseline to Week 12 in the MD part. RESULTS: 96 patients were enrolled in this study (SAD, n = 42; MD, n = 54). In SAD, CJM112 doses from 15 mg and above demonstrated higher PASI responses compared with placebo at Week 12. CJM112 450 mg did not add further efficacy, but efficacy duration was prolonged compared with CJM112 150 mg. CJM112 MD resulted in a dose-dependent decrease in PASI over time to Week 12. CJM112 150 mg high frequency did not exceed the effect of CJM112 150 mg low frequency and had similar efficacy to secukinumab 150 mg. The safety profile of CJM112 was as expected for an antibody targeting IL-17A/IL-17AF. CONCLUSIONS: CJM112 had clinical efficacy in moderate to severe psoriasis and was generally safe and well tolerated in the doses tested. Additional neutralization of IL-17AF did not translate to increased clinical efficacy compared with secukinumab.

[Metabolic acidosis of surprising origin in a 61-year-old female patient]. / Metabolische Azidose mit überraschender Ursache bei einer 61-jährigen Patientin.

A 61-year-old female patient presented to the emergency room with nausea. Laboratory findings revealed metabolic acidosis, which had to be associated with a sodium-glucose co-transporter­2 (SGLT2) inhibitor. Due to increasing prescription rates of SGLT2 inhibitors for diabetes mellitus, congestive heart failure or chronic renal insufficiency, a growing numbers of cases of SGLT2 inhibitor-associated ketoacidosis should be expected. Calculating the anion gap can provide orientation in the case of acidosis of unknown origin. Presumably, a relevant proportion of such cases of ketoacidosis is currently being overlooked or its diagnosis delayed.

See (n)One, Do (n)One, Teach (n)One: Reality of Surgical Resident Training in Germany.

INTRODUCTION: Due to technological changes, working time restrictions and the creation of specialized centers, surgical training has changed. A competence-based learning technique of surgical skills is the sub-step practice approach, which has been proven important in nationwide opinion surveys. The aim of this prospective multi-center trial was to determine the status quo of the sub-step concept in Germany. METHODS: Over 6 months, the voluntarily participating centers evaluated the following index procedures: laparoscopic cholecystectomy (LCHE), laparoscopic and open sigmoid resection, minimally invasive inguinal hernia repair, thyroid resection and pylorus-preserving pancreaticoduodenectomy (PPPD). Patients with private insurance were excluded. The detailed sub-steps were documented as well as the reason why these were not performed. In addition, an online survey regarding the sub-step concept was performed before and after the study. RESULTS: In total, 21 centers included 2969 surgical procedures in 2018 for final analyses. While 24.4% of the procedures were performed by residents, sub-steps were performed in 22.2%. LCHE was most often performed completely by residents (43.3%), and PPPD revealed the highest rate of performed sub-steps (43.3%). Reasons for not assisting sub-steps to residents were often organizational and other reasons. After an initial increase, the number of performed sub-steps decreased significantly during the second half of the survey. The opinion survey revealed a high importance of the sub-step concept. The number of resident procedures was overestimated, and the number of performed sub-steps was underestimated. After the study, these estimations were more realistic. CONCLUSION: Even though the sub-step practice concept is considered highly important for surgical education, it needs to be put into practice more consequently. The current data suggest a low participation of surgical residents in the operating room, although the participating hospitals are most likely highly interested in surgical education, hence their voluntary participation. Conceptual changes and a control of surgical education are needed.

Ultrafast Relaxation Dynamics of the Antiferrodistortive Phase in Ca Doped SrTiO_{3}.

The ultrafast dynamics of the octahedral rotation in Ca:SrTiO_{3} is studied by time-resolved x-ray diffraction after photoexcitation over the band gap. By monitoring the diffraction intensity of a superlattice reflection that is directly related to the structural order parameter of the soft-mode driven antiferrodistortive phase in Ca:SrTiO_{3}, we observe an ultrafast relaxation on a 0.2 ps timescale of the rotation of the oxygen octahedron, which is found to be independent of the initial temperature despite large changes in the corresponding soft-mode frequency. A further, much smaller reduction on a slower picosecond timescale is attributed to thermal effects. Time-dependent density-functional-theory calculations show that the fast response can be ascribed to an ultrafast displacive modification of the soft-mode potential towards the normal state induced by holes created in the oxygen 2p states.

Structured assessment of laparoscopic camera navigation skills: the SALAS score.

BACKGROUND: Tools are needed to assess laparoscopic camera navigation (LCN) in the operating room. Here, we aimed to develop an objective rating scale for LCN. STUDY DESIGN: We defined the following key aspects of LCN: operational field centering, correct angle of the horizon, correct instrument visualization, verbal commands from the operating surgeon, and manual corrections from the operating surgeon. We then developed a score based on intraoperative error evaluation from intraoperative recordings of 80 procedures. Finally, the newly developed score was validated by four different raters using video-based analysis of 20 elective laparoscopic cholecystectomies. RESULTS: We developed and validated a tool for the structured assessment of laparoscopic assistant skills (SALAS). This score showed good internal consistency, with a Cronbach's alpha of > 0.7. Intraclass correlation revealed a low interrater variability (ICC 0.866) for the total score. Comparison of experienced and inexperienced camera assistants revealed significantly better SALAS scores for experienced assistants (p < 0.05). CONCLUSION: Our present results show that SALAS score is valid, reliable, and practicable. This score can be used for future investigations of camera navigation efficiency and training.

Ultrafast Formation of a Charge Density Wave State in 1T-TaS_{2}: Observation at Nanometer Scales Using Time-Resolved X-Ray Diffraction.

Femtosecond time-resolved x-ray diffraction is used to study a photoinduced phase transition between two charge density wave (CDW) states in 1T-TaS_{2}, namely the nearly commensurate (NC) and the incommensurate (I) CDW states. Structural modulations associated with the NC-CDW order are found to disappear within 400 fs. The photoinduced I-CDW phase then develops through a nucleation and growth process which ends 100 ps after laser excitation. We demonstrate that the newly formed I-CDW phase is fragmented into several nanometric domains that are growing through a coarsening process. The coarsening dynamics is found to follow the universal Lifshitz-Allen-Cahn growth law, which describes the ordering kinetics in systems exhibiting a nonconservative order parameter.

[Survey of Training in Laparoscopic Skills in Germany]. / Umfrage zum Training laparoskopischer Fertigkeiten in Deutschland.

Background: Training in laparoscopic skills on simulators such as box-, POP- or VR-trainers improves intraoperative performance. Although this training is not mandatory in Germany at the moment, certified centres for minimally invasive surgery need to account for training opportunities. According to previous surveys, laparoscopic simulators are desired, yet not sufficiently available. The aim of the current project was a structured analysis of laparoscopic simulation sites in Germany. Materials and Methods: An online survey was performed among members of the "Deutsche Gesellschaft für Allgemein- und Viszeralchirurgie". This consisted of 16 questions on the availability, type, use and financing of a laparoscopic simulator. If more than one person in an institution completed the questionnaire, answers were pooled and an analysis of clinics as well as single persons was performed. Results: Of 4605 persons, 422 participants (9.2 %) from 265 different departments completed the survey. In 140 Institutions (52.8 %) a simulator for laparoscopic training was present. No training possibility was available in 37.8 % (n = 99) of the hospitals. A curriculum for laparoscopic training was obtained in 43.3 % (n = 103) of the participants with laparoscopic training facilities. The use of available simulators by surgical residents increased when they were embedded in a mandatory training curriculum (at least monthly use: 33.3 vs. 57.1 %). Conclusion: Compared to previous surveys, the proportion of hospitals with simulators is increasing. Their use is currently very heterogenous. A mandatory basic curriculum may encourage acquisition of more simulators. A DGAV database is supposed to encourage cooperation between training centres and clinics without simulators.

Glomerular development--shaping the multi-cellular filtration unit.

The glomerulus represents a highly structured filtration unit, composed of glomerular endothelial cells, mesangial cells, podocytes and parietal epithelial cells. During glomerulogenesis an intricate network of signaling pathways involving transcription factors, secreted factors and cell-cell communication is required to guarantee accurate evolvement of a functional, complex 3-dimensional glomerular architecture. Here, we want to provide an overview on the critical steps and relevant signaling cascades of glomerular development.

Co-sputtered MoRe thin films for carbon nanotube growth-compatible superconducting coplanar resonators.

Molybdenum rhenium alloy thin films can exhibit superconductivity up to critical temperatures of T(c)=15K. At the same time, the films are highly stable in the high-temperature methane/hydrogen atmosphere typically required to grow single wall carbon nanotubes. We characterize molybdenum rhenium alloy films deposited via simultaneous sputtering from two sources, with respect to their composition as function of sputter parameters and their electronic dc as well as GHz properties at low temperature. Specific emphasis is placed on the effect of the carbon nanotube growth conditions on the film. Superconducting coplanar waveguide resonators are defined lithographically; we demonstrate that the resonators remain functional when undergoing nanotube growth conditions, and characterize their properties as function of temperature. This paves the way for ultra-clean nanotube devices grown in situ onto superconducting coplanar waveguide circuit elements.

[Computer-assisted 3D-navigated laparoscopic resection of a vanished colorectal liver metastasis after chemotherapy]. / Die verschwundene Lebermetastase - Neues Einsatzgebiet für die computerassistierte 3D-navigierte laparoskopische Leberesektion?

BACKGROUND: Modern chemotherapy regimen for colorectal cancer results in complete radiologic remission in a substantial number of cases. However, these "vanished liver metastases" (VLM) often contain vital tumor cells, which mandates the resection of such lesions. In these cases, intraoperative identification of VLM can be challenging, in particular in laparoscopic approaches. We describe the first laparoscopic computer-assisted 3D-navigated resection of a VLM. CASE REPORT: A 60-year-old patient with a synchronous liver metastasis (segment IVb) of sigmoid colon cancer (T4 N1 M1) was referred to our center for elective liver resection after laparoscopic sigmoid resection and systemic chemotherapy (FOLFIRI/Panitumumab). The metastasis was not visible anymore on preoperative CT or sonography. Thus, a 3 D reconstruction of the liver was performed. The size of the initial metastasis (before chemotherapy) was transferred into the current CT. A computer-assisted 3D-navigated laparoscopic resection of the metastasis was performed on these fused images. The metastasis was also not clearly visible upon intraoperative ultrasound. Histology of the resected specimen revealed a 0.5 cm metastasis with predominantly vital tumor cells (regression degree 4 of Rubbia-Brandt) and a sufficient resection margin of at least 7 mm. The postoperative course was uneventful. CONCLUSION: Computer-assisted 3D-navigation enabled a safe oncologic resection of a vanished liver metastasis after chemotherapy. This technique was particularly helpful due to the limited haptic feedback of laparoscopic surgery. Further studies are necessary to verify the clinical benefit of computer assisted 3D-navigated liver surgery.

[Extended Left Hemihepatectomy with Reconstruction of The Right Liver Vein in a Patient with an Intrahepatic Cholangiocellular Carcinoma]. / Erweiterte Hemihepatektomie links mit Rekonstruktion der rechten Lebervene bei intrahepatischem cholangiozellulärem Karzinom.

Extended left hemihepatectomy (left trisectionectomy) with resection of liver segments 1, 2, 3, 4 a/b, 5 and 8 is a challenging procedure. In well-selected patients, the indication for this procedure may offer the chance of curative resection for primary or secondary liver tumours in complicated locations. Morbidity and mortality are increased compared to non-extended liver resections. This procedure requires precise imaging and accurate surgical planning in due consideration of the remaining liver volume and additional factors such as preliminary damage of the liver parenchyma caused by chemotherapy or fibrosis/cirrhosis. Left trisectionectomy is necessary in tumours affecting either the middle and left hepatic vein or the blood vessels of the liver hilum to the left and middle liver sector. The procedure necessitates the preservation of the right hepatic vein and the portal-venous and arterial branches supplying segments 6 and 7, as well as the bile ducts of these segments. This video article illustrates the surgical procedure of extended left hemihepatectomy performed due to an intrahepatic cholangiocellular carcinoma, which centrally surrounds the left and middle hepatic vein and potentially infiltrates the right hepatic vein. This condition requires the tangential resection and reconstruction of the right hepatic vein.

[Technique of Mesohepatectomy]. / Technik der Mesohepatektomie.

In patients with primary or secondary malignant central liver tumours, the standard surgical procedure is extended left or right hemihepatectomy. Since extended resections are associated with increased morbidity and mortality and a loss of a large amount of functional liver parenchyma, central liver resection or mesohepatectomy (resection of segments 4a/4b, 5 and 8) with or without the resection of segment 1 is an alternative procedure, although technically demanding and not widely used so far. Resection margins are to the right of the falciform ligament and at the border between segments 5/6 and 7/8, which can be difficult to differentiate. Intraoperative sonography is highly recommended. The current video shows the technique of mesohepatectomy under exclusion of segment 1 in a case of a central colorectal liver metastasis.

[3D Virtual Reality Laparoscopic Simulation in Surgical Education - Results of a Pilot Study]. / Virtuelle 3-D-Laparoskopie-Simulation in der chirurgischen Aus- und Weiterbildung - Ergebnisse einer Pilotstudie.

BACKGROUND: The use of three-dimensional imaging in laparoscopy is a growing issue and has led to 3D systems in laparoscopic simulation. Studies on box trainers have shown differing results concerning the benefit of 3D imaging. There are currently no studies analysing 3D imaging in virtual reality laparoscopy (VRL). MATERIALS AND METHODS: Five surgical fellows, 10 surgical residents and 29 undergraduate medical students performed abstract and procedural tasks on a VRL simulator using conventional 2D and 3D imaging in a randomised order. RESULTS: No significant differences between the two imaging systems were shown for students or medical professionals. Participants who preferred three-dimensional imaging showed significantly better results in 2D as wells as in 3D imaging. DISCUSSION: First results on three-dimensional imaging on box trainers showed different results. Some studies resulted in an advantage of 3D imaging for laparoscopic novices. This study did not confirm the superiority of 3D imaging over conventional 2D imaging in a VRL simulator. CONCLUSION: In the present study on 3D imaging on a VRL simulator there was no significant advantage for 3D imaging compared to conventional 2D imaging.

A time-dependent order parameter for ultrafast photoinduced phase transitions.

Strongly correlated electron systems often exhibit very strong interactions between structural and electronic degrees of freedom that lead to complex and interesting phase diagrams. For technological applications of these materials it is important to learn how to drive transitions from one phase to another. A key question here is the ultimate speed of such phase transitions, and to understand how a phase transition evolves in the time domain. Here we apply time-resolved X-ray diffraction to directly measure the changes in long-range order during ultrafast melting of the charge and orbitally ordered phase in a perovskite manganite. We find that although the actual change in crystal symmetry associated with this transition occurs over different timescales characteristic of the many electronic and vibrational coordinates of the system, the dynamics of the phase transformation can be well described using a single time-dependent 'order parameter' that depends exclusively on the electronic excitation.

Updated Next-to-Next-to-Leading-Order QCD Predictions for the Weak Radiative B-Meson Decays.

Weak radiative decays of the B mesons belong to the most important flavor changing processes that provide constraints on physics at the TeV scale. In the derivation of such constraints, accurate standard model predictions for the inclusive branching ratios play a crucial role. In the current Letter we present an update of these predictions, incorporating all our results for the O(α_{s}^{2}) and lower-order perturbative corrections that have been calculated after 2006. New estimates of nonperturbative effects are taken into account, too. For the CP- and isospin-averaged branching ratios, we find B_{sγ}=(3.36±0.23)×10^{-4} and B_{dγ}=(1.73_{-0.22}^{+0.12})×10^{-5}, for E_{γ}>1.6 GeV. Both results remain in agreement with the current experimental averages. Normalizing their sum to the inclusive semileptonic branching ratio, we obtain R_{γ}≡(B_{sγ}+B_{dγ})/B_{cℓν}=(3.31±0.22)×10^{-3}. A new bound from B_{sγ} on the charged Higgs boson mass in the two-Higgs-doublet-model II reads M_{H^{±}}>480 GeV at 95% C.L.

In vitro evaluation of cytomegalovirus-specific hyperimmune globulins vs. standard intravenous immunoglobulins.

BACKGROUND AND OBJECTIVES: To evaluate standard intravenous immunoglobulin (IVIG) as an alternative to intravenous cytomegalovirus hyperimmune immunoglobulin (CMVIG) for prophylaxis and therapy of cytomegalovirus (CMV) disease, we measured the ELISA and neutralizing titres of CMV-specific antibodies in CMVIG and IVIG preparations. MATERIALS AND METHODS: Anti-CMV-IgG ELISA and neutralizing titres (fibroblast-based test) in CMVIG CG (Cytogam®, n = 20), CMVIG CT (Cytotect® CP, n = 3), IVIG P (Privigen®, n = 32) and IVIG K/G (Kiovig®/Gammagard®, n = 5) were compared, and IgG subclasses 1-4 were determined by nephelometry. RESULTS: Cytomegalovirus hyperimmune immunoglobulins contained more than fourfold higher CMV ELISA and CMV-neutralizing activity per gram of IgG than the standard IVIGs. Pooled data for all four products showed a significant correlation between anti-CMV-IgG ELISA and neutralizing titres (r = 0·93, P < 0·001). There was a good correlation between the IgG3 content and CMV-neutralizing antibodies amongst lots of CMVIGs (r = 0·91, P = 0·01), but this did not extend to the IVIGs. CMVIG CG contained the highest CMV-neutralizing activity (3497 ± 395 PEIU/g IgG) of any product tested. CONCLUSION: The higher anti-CMV neutralization capacity of CMVIG per gram of IgG vs. standard IVIG suggests that standard IVIGs are not equivalent to or interchangeable with CMVIG.

Oxygen reduction via grain boundary transport in thin film platinum electrodes on yttria stabilized zirconia.

Model-type sputter deposited platinum microelectrodes with different grain sizes were investigated on single crystalline yttria stabilized zirconia (YSZ) by means of impedance spectroscopy. Measurements on single platinum microelectrodes could be continuously performed for > 100 h and from 250 to 800 °C without losing contact. From the temperature dependence, two parallel reaction pathways for oxygen reduction could be identified. Above 450 °C, a surface path with a rate determining step located at the three phase boundary is predominant. Its polarization resistance is independent of the Pt grain size and exhibits an activation energy of ca. 1.8 eV. In the low temperature regime (< 450 °C) a bulk path through Pt was verified, with an electrode polarization resistance depending on the Pt grain size. This resistance is only slightly thermally activated and the rate limiting step is most probably oxygen diffusion along Pt grain boundaries.