Influence of Slim Rod Material Properties to the Siemens Feed Rod and the Float Zone Process

AbstractThe identification and understanding of material properties influencing the float zone process is important to crystallize high purity silicon for high efficiency solar cells. Also the knowledge of minimal requirements to crystallize monocrystalline silicon with the float zone process is of interest from an economic point of view. In the present study, feed rods for the float zone process composed of a central slim rod and the deposited silicon from the Siemens process are investigated. Previous studies have shown that the slim rod has a significant impact on the purity and suitability for further crystallization processes. In particular, contaminations like substitutional carbon and the presence of precipitates as well as the formation of oxide layers play an important role and are investigated in detail. For this purpose different slim rod materials were used in deposition and float zone crystallization experiments. Samples were prepared by cross sectioning and core drilling of Siemens rods, which were recrystallized with the float zone process. Recrystallized drilled cores are analyzed with FT-IR spectrometry concerning the carbon and oxygen content. To estimate the grain growth behavior on the slim rod surface in dependence of the used slim rod material, EBSD mappings inside a SEM are performed on squared and circular slim rods. TEM analysis was used to investigate the presence of an oxide layer at the interface between slim rod and deposited polycrystalline silicon. Additionally the influence of a nitrogen-containing gas atmosphere during the slim rod pulling is investigated by IR microscopy and ToF-SIMS regarding Si3N4 precipitation

A retrospective study on disease management in children and adolescents with phenylketonuria during the Covid-19 pandemic lockdown in Austria

BACKGROUND In classical phenylketonuria (PKU) phenylalanine (Phe) accumulates due to functional impairment of the enzyme phenylalanine hydroxylase caused by pathogenic variants in the PAH gene. PKU treatment prevents severe cognitive impairment. Blood Phe concentration is the main biochemical monitoring parameter. Between appointments and venous blood sampling, Austrian PKU patients send dried blood spots (DBS) for Phe measurements to their centre. Coronavirus disease-19 (COVID-19), caused by the SARS CoV-2 virus, was classified as a pandemic by the World Health Organization in March 2020. In Austria, two nationwide lockdowns were installed during the first and second pandemic wave with variable regional and national restrictions in between. This retrospective questionnaire study compared the frequency of Phe measurements and Phe concentrations during lockdown with the respective period of the previous year in children and adolescents with PKU and explored potential influencing factors. RESULTS 77 patients (30 female, 47 male; mean age 12.4 [8-19] years in 2020) from five centres were included. The decline of venous samples taken on appointments in 2020 did not reach significance but the number of patients with none or only one DBS tripled from 4 (5.2%) in 2019 to 12 (15.6%) in 2020. Significantly more patients had a decline than a rise in the number of DBS sent in between 2019 and 2020 (p < 0.001; Chi$^{2}$ = 14.79). Especially patients ≥ 16 years sent significantly less DBS in 2020 (T = 156, p = 0.02, r = 0.49). In patients who adhered to DBS measurements, Phe concentrations remained stable. Male or female sex and dietary only versus dietary plus sapropterin treatment did not influence frequency of measurements and median Phe. CONCLUSION During the COVID pandemic, the number of PKU patients who stopped sending DBS to their metabolic centre increased significantly, especially among those older than 16 years. Those who kept up sending DBS maintained stable Phe concentrations. Our follow-up system, which is based on DBS sent in by patients to trigger communication with the metabolic team served adherent patients well. It failed, however, to actively retrieve patients who stopped or reduced Phe measurements

p. 325–330 2002 Binocular 3-D Object Tracking with Varying Focal Lengths

In this paper we discuss some practical facets of active camera control during 3-D object tracking. The basis of our investigation is an active binocular camera system looking onto a scene to track a moving object in 3-D. Tracking is done in a data driven manner using an extented version of the region based method that was proposed earlier by Hager and Belhumeur. Triangulation of the extracted objects in the two image planes lead to an estimation of the 3-D position of the moving object. To keep the moving object in the center of the image the tilt and vergence axis of the binocular camera system is controlled. The important question for such an experimental setup is which parameters do influence the quality of the final 3-D estimation. The main effects we are concentrating on is the accuracy of the 2-D localization in the image plane depending on the focal length of the camera. Also the consequences of errors in the synchronization between image acquisition and motor control of the camera system are shortly discussed. All considerations are verified in real-time experiments

2002 ENTROPY BASED CAMERA CONTROL FOR VISUAL OBJECT TRACKING

In active visual 3-D object tracking one goal is to control the pan and tilt axes of the involved cameras to keep the tracked object in the centers of the fields of view. In this paper we present a novel method, based on an information theoretic measure that manages this task. The main advantage of the proposed approach is that there is no more need for an explicit formulation of a camera controller, like a PIDcontroller or something similar. For the case of Kalman filter based tracking, we demonstrate the practicability and evaluate the accuracy of the proposed method in simulations as well as in real-time tracking experiments. 1

Long-term outcome of LRBA deficiency in 76 patients after various treatment modalities as evaluated by the immune deficiency and dysregulation activity (IDDA) score

Background: Recent findings strongly support hematopoietic stem cell transplantation (HSCT) in patients with severe presentation of LPS-responsive beige-like anchor protein (LRBA) deficiency, but long-term follow-up and survival data beyond previous patient reports or meta-reviews are scarce for those patients who do not receive a transplant. Objective: This international retrospective study was conducted to elucidate the longitudinal clinical course of patients with LRBA deficiency who do and do not receive a transplant. Method: We assessed disease burden and treatment responses with a specially developed immune deficiency and dysregulation activity score, reflecting the sum and severity of organ involvement and infections, days of hospitalization, supportive care requirements, and performance indices. Results: Of 76 patients with LRBA deficiency from 29 centers (median follow-up, 10 years; range, 1-52), 24 underwent HSCT from 2005 to 2019. The overall survival rate after HSCT (median follow-up, 20 months) was 70.8% (17 of 24 patients); all deaths were due to nonspecific, early, transplant-related mortality. Currently, 82.7% of patients who did not receive a transplant (43 of 52; age range, 3-69 years) are alive. Of 17 HSCT survivors, 7 are in complete remission and 5 are in good partial remission without treatment (together, 12 of 17 [70.6%]). In contrast, only 5 of 43 patients who did not receive a transplant (11.6%) are without immunosuppression. Immune deficiency and dysregulation activity scores were significantly lower in patients who survived HSCT than in those receiving conventional treatment (P = .005) or in patients who received abatacept or sirolimus as compared with other therapies, and in patients with residual LRBA expression. Higher disease burden, longer duration before HSCT, and lung involvement were associated with poor outcome. Conclusion: The lifelong disease activity, implying a need for immunosuppression and risk of malignancy, must be weighed against the risks of HSCT. Keywords: CTLA4; Inborn error of immunity; abatacept; clinical score; combined immunodeficiency; hematopoietic stem cell transplantation; immune dysregulation; performance scale; primary immunodeficiency disorder; sirolimus

Plenoptic Models in Robot Vision

this article, we propose a new kind of model for robot vision, the so called plenoptic model, a model that can be acquired fully automatically. This is regarded in this article as learning. The key idea is to collect a sequence of images from objects or scenes using a hand--held camera. These images together with some extra information, which is computed automatically during model building, serve as a model of the object or scene. Using this model photo--realistic views from objects and scenes can be created (rendered) synthetically, even if the view has not been observed befor