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Background/Objectives: This study aims to investigate the long-term effect of inactive systemic lupus erythematosus (SLE) on the retinal microcirculation measured via optical coherence tomography angiography (OCT-A). Methods: Twenty-four eyes of 24 patients with inactive SLE under hydroxychloroquine (HCQ) therapy were included. The OCT-A data (mainly vessel density (VD) and foveal avascular zone (FAZ) data of the superficial and of the deep capillary plexus (SCP, DCP) and the choriocapillaris (CC)) were analyzed and compared between the baseline examination (t0) and 2 years later (t1). Results: At t1, VD in the whole en face SCP and in the CC was notably reduced compared to t0 (SCP: p = 0.001, CC: p = 0.013). VD in the DCP, CRT and FAZ area showed no difference at t1 compared to t0 (DCP: p = 0.128, FAZ: p = 0.332, CRT fovea: p = 0.296). Correlation analysis between the increase in cumulative doses of HCQ between t0 and t1 and the VD of the whole en face SCP did not show any correlation (Spearman r = 0.062 (95% CI −0.367; 0.477). Conclusions: SLE patients demonstrated a decrease in the retinal VD of the SCP and CC over a 2-year period. There was no correlation with the change in cumulative doses of HCQ. These results suggest an ongoing effect of the disease on the retinal and choriocapillary microcirculation. [ABSTRACT FROM AUTHOR]

Keratoconus (KC) is the most common corneal ectasia. Optical coherence tomography angiography (OCT-A) is a relatively new non-invasive imaging technique that allows the visualization and quantification of retinal and choriocapillary blood vessels. The aim of this study is to assess retinal and choriocapillary vessel density (VD) differences between KC patients and healthy controls and to investigate correlations between VD and KC severity. Fifty-two eyes were included in this exploratory study: twenty-six eyes from 26 KC patients and twenty-six eyes from 26 age- and gender-matched healthy controls. All patients underwent Scheimpflug corneal topography with Pentacam, axis lengths measurement and optical coherence tomography angiography (OCT-A). The thinnest spot in corneal pachymetry, maximum K (Kmax) and KC severity indices from the Belin/Ambrósio enhanced ectasia display (BAD) were also assessed. There was a distinct reduction particularly in the retinal VD of the superficial capillary plexus (SCP). Correlation analyses showed strong and moderate negative correlations between the VD in the macular SCP and BAD KC scores and between the SCP VD and Kmax. There was no difference in retinal thickness between the KC and healthy controls. With this study, further evidence for altered VD measurements by OCT-A in KC patients is given. For the first time, we demonstrated negative correlations between BAD KC scores and retinal blood vessel alterations. A major limitation of the study is the relatively small sample size. Since an artefactual reduction of the quantitative OCT-A measurements due to irregular corneal topography in KC must be assumed, it remains to be investigated whether there are also actual changes in the retinal microcirculation in KC. [ABSTRACT FROM AUTHOR]

Astronomers are now able to detect planets orbiting stars other than the Sun where life may exist, and living generations could see the signatures of extra-terrestrial life being detected. Should it turn out that we are not alone in the Universe, it will fundamentally affect how humanity understands itself—and we need to be prepared for the consequences. A Discussion Meeting held at the Royal Society in London, 6–9 Carlton House Terrace, on 25–26 January 2010, addressed not only the scientific but also the societal agenda, with presentations covering a large diversity of topics. [ABSTRACT FROM AUTHOR]

Although Einstein originally judged that ‘there is no great chance of observing this phenomenon’, the ‘most curious effect’ of the bending of starlight by the gravity of intervening foreground stars—now commonly referred to as ‘gravitational microlensing’—has become one of the successfully applied techniques to detect planets orbiting stars other than the Sun, while being quite unlike any other. With more than 400 extra-solar planets known altogether, the discovery of a true sibling of our home planet seems to have become simply a question of time. However, in order to properly understand the origin of Earth, carrying all its various life forms, models of planet formation and orbital evolution need to be brought into agreement with the statistics of the full variety of planets like Earth and unlike Earth. Given the complementarity of the currently applied planet detection techniques, a comprehensive picture will only arise from a combination of their respective findings. Gravitational microlensing favours a range of orbital separations that covers planets whose orbital periods are too long to allow detection by other indirect techniques, but which are still too close to their host star to be detected by means of their emitted or reflected light. Rather than being limited to the Solar neighbourhood, a unique opportunity is provided for inferring a census of planets orbiting stars belonging to two distinct populations within the Milky Way, with a sensitivity not only reaching down to Earth mass, but even below, with ground-based observations. The capabilities of gravitational microlensing extend even to obtaining evidence of a planet orbiting a star in another galaxy. [ABSTRACT FROM AUTHOR]

Presents information on a study which investigated the extent to which the reactivities of chloromuconates can be accounted for and examined the substrate specificity of the muconate cycloisomerases from Pseudominas putida. Information on the differential specificities of muconate cycloisomerases Conversion of 2- and 3-substituted muconates; Results of the study.

Shows the conversion of 2-chloro-cis,cis-muconate by purified preparations of the pJP4- and pAC27-encoded chloromuconate cycloisomerases to trans-dienelactone (trans-4-carboxymethylenebut-2-en-4-olide). Kinetic parameters of the pJP4-encoded chloromuconate cycloisomerase; High-performance liquid chromatographic analyses.

Successful analytics solutions that provide valuable insights often hinge on the connection of various data sources. While it is often feasible to generate larger data pools within organizations, the application of analytics within (inter-organizational) business networks is still severely constrained. As data is distributed across several legal units, potentially even across countries, the fear of disclosing sensitive information as well as the sheer volume of the data that would need to be exchanged are key inhibitors for the creation of effective system-wide solutions—all while still reaching superior prediction performance. In this work, we propose a meta machine learning method that deals with these obstacles to enable comprehensive analyses within a business network. We follow a design science research approach and evaluate our method with respect to feasibility and performance in an industrial use case. First, we show that it is feasible to perform network-wide analyses that preserve data confidentiality as well as limit data transfer volume. Second, we demonstrate that our method outperforms a conventional isolated analysis and even gets close to a (hypothetical) scenario where all data could be shared within the network. Thus, we provide a fundamental contribution for making business networks more effective, as we remove a key obstacle to tap the huge potential of learning from data that is scattered throughout the network. [ABSTRACT FROM AUTHOR]

The capabilities of supervised machine learning (SML), especially compared to human abilities, are being discussed in scientific research and in the usage of SML. This study provides an answer to how learning performance differs between humans and machines when there is limited training data. We have designed an experiment in which 44 humans and three different machine learning algorithms identify patterns in labeled training data and have to label instances according to the patterns they find. The results show a high dependency between performance and the underlying patterns of the task. Whereas humans perform relatively similarly across all patterns, machines show large performance differences for the various patterns in our experiment. After seeing 20 instances in the experiment, human performance does not improve anymore, which we relate to theories of cognitive overload. Machines learn slower but can reach the same level or may even outperform humans in 2 of the 4 of used patterns. However, machines need more instances compared to humans for the same results. The performance of machines is comparably lower for the other 2 patterns due to the difficulty of combining input features. [ABSTRACT FROM AUTHOR]

As a rare and often misdiagnosed disease of the lacrimal apparatus, only limited data exist on long-term outcomes of surgical methods for the treatment of primary canaliculitis. The aim of this study was to evaluate canaliculotomy with silicone tube intubation (STI) as a surgical procedure for canaliculitis in a long-term follow-up setting. A total of 25 eyes of 25 patients with canaliculitis treated with canaliculotomy and STI at the University of Muenster Medical Center, Germany, from 2015 to 2021 were included in this study. Data analysis involved clinical symptoms, complications, duration of STI and rate of recurrence. Mean patient age was 63.7 ± 17.2 years. After a follow-up time of 3.7 ± 1.5 years, 88% of cases showed no recurrence of inflammation. The mean duration of STI was 5.8 ± 3.4 months. Complications such as post-operative hemorrhage, spread of infection, obstruction of the canaliculus or migration of the STI were not observed in any of the patients. However, tube dislocation occurred in four cases, a pyogenic granuloma in two cases and a fistula formation in one case. The management of canaliculitis by canaliculotomy with STI showed very good postoperative outcomes and low complication rates in the long-term and can therefore be considered a safe and successful surgical approach. [ABSTRACT FROM AUTHOR]

The authors report on design, fabrication, and electro‐optical characterization of single‐frequency diode lasers emitting around 696, 707, and 712 nm. This has been achieved by a variation of the periods of the 10th order surface Bragg gratings implemented on a single epitaxial wafer. Depending on the wavelength, the devices achieved an optical output power of up to 60 mW at a current of 150 mA and spectral linewidths of about 400 kHz (full width at half maximum (FWHM)) and 20 kHz (Lorentzian). [ABSTRACT FROM AUTHOR]

We present a multi‐active‐region bipolar‐cascade distributed‐Bragg reflector (DBR) laser emitting around 910 nm. The three active regions and two tunnel junctions are located in a single waveguide core sharing the same third‐order vertical mode. A slope efficiency of 2.25 W/A was measured with a threshold current density of 400 A/cm2. Due to the implemented 7th Bragg order surface grating, the laser exhibits a narrow optical spectrum with a width of 0.3 nm and a thermal detuning of 60 pm/K. [ABSTRACT FROM AUTHOR]

A multi‐active‐region bipolar‐cascade edge‐emitting laser emitting at nearly 900 nm is presented. The three active regions and two tunnel junctions located in a single waveguide core share the same third‐order vertical mode. A slope efficiency of 3.6 W/A was measured with a threshold current density of 230 A/cm2. The epitaxial layer stack developed features with very low internal optical losses of 0.7 cm−1. The voltage extrapolated to vanishing current is only 0.3 V larger than 3 times the voltage of 1.4 V originating from the photon energy. [ABSTRACT FROM AUTHOR]

The recently discovered ferroelectric behavior of HfO2-based dielectrics yields the potential to overcome the main challenges of the ferroelectric field-effect transistors (FeFETs)—CMOS compatibility as well as scalability to the state-of-the-art technology nodes of logic transistors. In this paper, we study the impact of scaling on the memory performance of FeFET devices employing Si:HfO2 ferroelectric films. The operation capability was proven down to a gate length of 28 nm. Program/erase characteristics, endurance behavior, and retention properties were analyzed for FeFETs with gate lengths scaled down to 32 nm. The detected difference in the performance between the long and short channel devices could be for the most part attributed to transistor short channel effects. In addition, the effect of temperature on the device properties of Si:HfO2-based FeFETs was investigated in detail. The program/erase speed was ascertained to be independent of temperature. On the other hand, increase in temperature resulted in reduced initial memory window accompanied by its slightly accelerated decay with time. [ABSTRACT FROM AUTHOR]