Optische Vermessung mit Streifenlichtscannern – aus Industrie und Forschung nicht mehr wegzudenken

Aus der Einleitung: "Qualität nimmt als Wettbewerbsfaktor eine immer größere Rolle ein. Damit wächst auch der Bedarf an schneller Messtechnik zur präzisen geometrischen Erfassung unterschiedlicher Werkstücke. Ein weiterer Grund für diesen steigenden Bedarf sind der zunehmende Automatisierungsgrad und die Fertigungsgeschwindigkeit in der Produktion (Pfeifer 1998). Der Vorteil der optischen 3D-Messung gegenüber konventioneller Koordinatenmesstechnik besteht vor allem in der höheren Erfassungsgeschwindigkeit. Taktile Messgeräte können im Vergleich nur sehr wenige Messpunkte in einer bestimmten Zeit digitalisieren, optische Messgeräte hingegen große Flächen in wenigen Sekunden (Berndt 2008). Des Weiteren ist die optische Messung im Gegensatz zur taktilen Messung berührungslos, wodurch Schäden am Werkstück oder direkte Einflüsse des Werkstücks (weiche Oberflächen) auf die Messergebnisse vermieden werden. In der Fertigungsmesstechnik kommen optische Verfahren vorwiegend zur Bestimmung geometrischer Kenngrößen wie Abstand, Form, Profil oder Oberflächenstruktur zum Einsatz (Pfeifer 1998). So können z. B. in der Automobilindustrie Blechbauteile auf Ihre Maßhaltigkeit hin untersucht werden.

PROMIS CAT Forms Demonstrate Responsiveness in Patients Following Reverse Total Arthroplasty Across Numerous Health Domains

Aim: The purpose of this study was to investigate the responsiveness of three PROMIS CAT domains in patients undergoing reverse shoulder arthroplasty. Background: To better optimize the administration and postoperative tracking of patients using PROM, the Patient-Reported Outcomes Measurement Information System (PROMIS) was established by the National Institutes of Health. PROMIS CAT domains have been since validated in multiple orthopedic interventions of the shoulder, however, no one to date has studied the responsiveness of PROMIS CAT domains in a cohort of patients undergoing reverse shoulder arthroplasty. Methods: Patients undergoing reverse shoulder arthroplasty by a board-certified shoulder and elbow surgeon were included in this study. PROMIS CAT Upper Extremity Physical Function (“PROMIS-UE”), Pain Interference (“PROMIS-PI”), and Depression (“PROMIS-D”) scores were collected preoperatively and at five postoperative timepoints. Patient-centric demographic factors, range of motion, and clinical characteristics were also reviewed and analyzed for association with PROMIS scores. Results: 104 patients undergoing primary reverse shoulder arthroplasty were included in this study. The patient cohort consisted of 52 males (50.0%), an average age of 70.3 years (standard deviation, 11.2), and a BMI of 30.2 (standard deviation, 6.1). All three PROMIS domains showed significant improvement as early as 6 weeks after surgery, with values of 32.4 ± 6.6, 56.2 ± 7.5, and 44.6 ± 8.6, for PROMIS-UE, PROMIS-PI, and PROMIS-D, respectively. Significant improvements were noted for each postoperative timepoint thereafter, with 1-year follow up values as follows: 42.1 ± 8.7, 52.5 ± 8.6, and 43.6 ± 9.5 for PROMIS-UE, PROMIS-PI, and PROMIS-D, respectively. Moderate correlations were identified with postoperative PROMIS-UE and abduction (r=0.439, p\u3c0.01), as well as postoperative PROMIS-PI and PROMIS-D (r=0.502, p\u3c0.01). Conclusions: PROMIS CAT forms demonstrate responsiveness in patients undergoing reverse shoulder arthroplasty

Acute versus delayed reverse total shoulder arthroplasty for proximal humerus fractures in the elderly: Mid-term outcomes

Background: Treatment of proximal humerus fractures (PHFs) via reverse total shoulder arthroplasty (RTSA) has shown early promise when compared to historical treatment modalities. Ideal surgical timing remains unclear. The purpose of this study was to compare the outcomes of early versus delayed RTSA for PHF. We hypothesized that acute RTSA would display superior outcomes compared to those receiving delayed surgical intervention. Methods: This multicenter study retrospectively analyzed 142 patients who underwent RTSA for fracture. Patients treated within 4 weeks of injury were placed in the acute group (n = 102), and patients treated longer than 4 weeks after injury were placed in the chronic group (n = 38). A comprehensive panel of patient reported outcome measures, VAS pain scores, range of motion, and patient satisfaction were evaluated. Results: The acute group had significantly better final follow-up SPADI scores (20.8 ± 23.9 vs. 30.7 ± 31.7) (p\u3c0.05). No further differences were detected in other postoperative range of motion measurements, subjective outcomes, or VAS scores. Conclusions: Our results suggest that patients treated acutely display similar mid-term outcomes to those who receive delayed treatment. With this in mind, surgeons may first give consideration to a period of nonoperative treatment. Level of evidence: Level II

Association between IgM Anti-Herpes Simplex Virus and Plasma Amyloid-Beta Levels

OBJECTIVE: Herpes simplex virus (HSV) reactivation has been identified as a possible risk factor for Alzheimer's disease (AD) and plasma amyloid-beta (Aβ) levels might be considered as possible biomarkers of the risk of AD. The aim of our study was to investigate the association between anti-HSV antibodies and plasma Aβ levels. METHODS: The study sample consisted of 1222 subjects (73.9 y in mean) from the Three-City cohort. IgM and IgG anti-HSV antibodies were quantified using an ELISA kit, and plasma levels of Aβ(1-40) and Aβ(1-42) were measured using an xMAP-based assay technology. Cross-sectional analyses of the associations between anti-HSV antibodies and plasma Aβ levels were performed by multi-linear regression. RESULTS: After adjustment for study center, age, sex, education, and apolipoprotein E-e4 polymorphism, plasma Aβ(1-42) and Aβ(1-40) levels were specifically inversely associated with anti-HSV IgM levels (β = -20.7, P=0.001 and β = -92.4, P=0.007, respectively). In a sub-sample with information on CLU- and CR1-linked SNPs genotyping (n=754), additional adjustment for CR1 or CLU markers did not modify these associations (adjustment for CR1 rs6656401, β = -25.6, P=0.002 for Aβ(1-42) and β = -132.7, P=0.002 for Aβ(1-40;) adjustment for CLU rs2279590, β = -25.6, P=0.002 for Aβ(1-42) and β = -134.8, P=0.002 for Aβ(1-40)). No association between the plasma Aβ(1-42)-to-Aβ(1-40) ratio and anti-HSV IgM or IgG were evidenced. CONCLUSION: High anti-HSV IgM levels, markers of HSV reactivation, are associated with lower plasma Aβ(1-40) and Aβ(1-42) levels, which suggest a possible involvement of the virus in the alterations of the APP processing and potentially in the pathogenesis of AD in human

CMB-S4: Forecasting Constraints on Primordial Gravitational Waves

CMB-S4---the next-generation ground-based cosmic microwave background (CMB) experiment---is set to significantly advance the sensitivity of CMB measurements and enhance our understanding of the origin and evolution of the Universe, from the highest energies at the dawn of time through the growth of structure to the present day. Among the science cases pursued with CMB-S4, the quest for detecting primordial gravitational waves is a central driver of the experimental design. This work details the development of a forecasting framework that includes a power-spectrum-based semi-analytic projection tool, targeted explicitly towards optimizing constraints on the tensor-to-scalar ratio, $r$, in the presence of Galactic foregrounds and gravitational lensing of the CMB. This framework is unique in its direct use of information from the achieved performance of current Stage 2--3 CMB experiments to robustly forecast the science reach of upcoming CMB-polarization endeavors. The methodology allows for rapid iteration over experimental configurations and offers a flexible way to optimize the design of future experiments given a desired scientific goal. To form a closed-loop process, we couple this semi-analytic tool with map-based validation studies, which allow for the injection of additional complexity and verification of our forecasts with several independent analysis methods. We document multiple rounds of forecasts for CMB-S4 using this process and the resulting establishment of the current reference design of the primordial gravitational-wave component of the Stage-4 experiment, optimized to achieve our science goals of detecting primordial gravitational waves for $r > 0.003$ at greater than $5\sigma$, or, in the absence of a detection, of reaching an upper limit of $r < 0.001$ at $95\%$ CL.Comment: 24 pages, 8 figures, 9 tables, submitted to ApJ. arXiv admin note: text overlap with arXiv:1907.0447

Performance and characterization of the SPT-3G digital frequency-domain multiplexed readout system using an improved noise and crosstalk model

The third-generation South Pole Telescope camera (SPT-3G) improves upon its predecessor (SPTpol) by an order of magnitude increase in detectors on the focal plane. The technology used to read out and control these detectors, digital frequency-domain multiplexing (DfMUX), is conceptually the same as used for SPTpol, but extended to accommodate more detectors. A nearly 5× expansion in the readout operating bandwidth has enabled the use of this large focal plane, and SPT-3G performance meets the forecasting targets relevant to its science objectives. However, the electrical dynamics of the higher-bandwidth readout differ from predictions based on models of the SPTpol system due to the higher frequencies used and parasitic impedances associated with new cryogenic electronic architecture. To address this, we present an updated derivation for electrical crosstalk in higher-bandwidth DfMUX systems and identify two previously uncharacterized contributions to readout noise, which become dominant at high bias frequency. The updated crosstalk and noise models successfully describe the measured crosstalk and readout noise performance of SPT-3G. These results also suggest specific changes to warm electronics component values, wire-harness properties, and SQUID parameters, to improve the readout system for future experiments using DfMUX, such as the LiteBIRD space telescope

25th annual computational neuroscience meeting: CNS-2016

The same neuron may play different functional roles in the neural circuits to which it belongs. For example, neurons in the Tritonia pedal ganglia may participate in variable phases of the swim motor rhythms [1]. While such neuronal functional variability is likely to play a major role the delivery of the functionality of neural systems, it is difficult to study it in most nervous systems. We work on the pyloric rhythm network of the crustacean stomatogastric ganglion (STG) [2]. Typically network models of the STG treat neurons of the same functional type as a single model neuron (e.g. PD neurons), assuming the same conductance parameters for these neurons and implying their synchronous firing [3, 4]. However, simultaneous recording of PD neurons shows differences between the timings of spikes of these neurons. This may indicate functional variability of these neurons. Here we modelled separately the two PD neurons of the STG in a multi-neuron model of the pyloric network. Our neuron models comply with known correlations between conductance parameters of ionic currents. Our results reproduce the experimental finding of increasing spike time distance between spikes originating from the two model PD neurons during their synchronised burst phase. The PD neuron with the larger calcium conductance generates its spikes before the other PD neuron. Larger potassium conductance values in the follower neuron imply longer delays between spikes, see Fig. 17.Neuromodulators change the conductance parameters of neurons and maintain the ratios of these parameters [5]. Our results show that such changes may shift the individual contribution of two PD neurons to the PD-phase of the pyloric rhythm altering their functionality within this rhythm. Our work paves the way towards an accessible experimental and computational framework for the analysis of the mechanisms and impact of functional variability of neurons within the neural circuits to which they belong