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Patient: Male, 39-year-old Final Diagnosis: SARS-CoV-2 Symptoms: Fatigue • dyspnea • fever Medication: Dexamethasone • heparin Clinical Procedure: C-reactive protein apheresis Specialty: Immunology Objective: Unusual clinical course Background: High C-reactive protein (CRP) plasma levels in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection are associated with poor prognosis. CRP, by activating the classical complement pathway and interacting with macrophages via Fc gamma receptors, can cause pulmonary inflammation with subsequent fibrosis. Recently, we have reported first-in-man CRP apheresis in a “high-risk” COVID-19 patient. Treatment was unfortunately clinically unsuccessful. Here, we report on successful CRP apheresis treatment in a “lower-risk” COVID-19 patient with respiratory failure. Case Report: A 39-year-old male patient suffering from fatigue, dyspnea, and fever for 4 days was referred to us. The patient had to be intubated. Polymerase chain reaction (PCR) analysis of a throat smear revealed SARS-CoV-2 infection. Mutation analysis revealed the VOC B. 1.1.7 variant. CRP levels were 79.2 mg/L and increased to 161.63 mg/L. Procalcitonin (PCT) levels were continuously normal (

The influence of different melt streams on the distribution of phosphorus in multi-crystalline silicon ingot was studied. Phosphorus-doped multi-crystalline silicon (mc-Si) ingots were directionally solidified using travelling magnetic fields (TMF) to alter axial phosphorus profiles. Resistivity distributions in the crystallized n-type ingots were measured along the ingot length. Different Lorentz forces were applied in order to enhance melt stirring and with that to transport phosphorus more rapid towards the melt surface. A new rectangular setup was developed, which enables simultaneous directional solidification of 4 G0-sized mc-Si ingots (80 x 80 x 60 mm3) under the influence of TMF. 900 g ingots with different initial level of phosphorus doping were grown, and dopant concentrations in ingots were related to stirring intensities. The phosphorus evaporation rate significantly affects axial dopant profile of mc-Si material, thus this approach can be used as a powerful tool to control and tailor resistivity distribution along phosphorus-doped mc-Si ingots.

The lateral photovoltage scanning method (LPS) can be used to detect undesired impurities which appear in silicon crystals during growth. Our goal is to make a digital twin of the LPS method. To this end, we replace inflexible blackbox code with a physics preserving finite volume discretization, confirming three theoretical results via a new simulation strategy. By making the simulation transparent, it becomes easier to trace intermediate results and gain theoretical insights.

The goal of this paper is to model and simulate the lateral photovoltage scanning (LPS) method which detects inhomogeneities in semiconductor crystals. Our drift-diffusion model is based on the semiconductor device equations combined with an implicit boundary condition which models a volt meter. To validate our 2D and 3D finite volume simulations, we use theory developed by Tauc [1] to derive three analytical predictions which our simulation results corroborate, even for anisotropic 2D and 3D meshes. Our code runs about two orders of magnitudes faster than earlier implementations based on commercial software [2] . It also performs well for small doping concentrations which previously could not be simulated at all due to numerical instabilities. We present a convergence study which shows that the LPS voltage converges quadratically. Finally, our simulations provide experimentalists with reference laser powers for which meaningful voltages can still be measured. For higher laser power the screening effect does not allow this anymore.

Crystalline silicon is grown onto an amorphous silicon (a-Si) seed layer from a liquid tin solution (steady state liquid phase epitaxy, SSLPE). To investigate the crystallization of embedded a-Si during our process, we adapted Raman measurements for fast mapping, with a dwell time of just one second per single measurement. A purposely developed imaging algorithm which performs point-by-point gauss fitting provides adequate visualization of the data. We produced scans of a-Si layers showing crystalline structures formed in the a-Si matrix during processing. Compared to scanning electron microscopy images which reveal merely the topography of the grown layer, new insights are gained into the role of the seed layer by Raman mapping. As part of a series of SSLPE experiments, which were interrupted at various stages of growth, we show that plate-like crystallites grow laterally over the a-Si layer while smaller, randomly orientated crystals arise from the a-Si layer. Results are confirmed by an in situ TEM experiment of the metal-induced crystallization. Contrary to presumptions, initially formed surface crystallites do not originate from the seed layer and are irrelevant to the final growth morphology, since they dissolve within minutes due to Ostwald ripening. The a-Si layer crystallizes within minutes as well, and crystallites of the final morphology originate from seeds of this layer.

The lateral photovoltage scanning method (LPS) detects doping inhomogeneities in semiconductors such as Si, Ge and $${\hbox {Si}_{\hbox {x}}\hbox {Ge}_{1-\hbox {x}}}$$ Si x Ge 1 - x in a cheap, fast and nondestructive manner. LPS relies on the bulk photovoltaic effect and thus can detect any physical quantity affecting the band profiles of the sample. LPS finite volume simulation using commercial software suffer from long simulation times and convergence instabilities. We present here an open-source finite volume simulation for a 2D Si sample using the simulator. For low injection conditions we show that the LPS voltage is proportional to the doping gradient. For higher injection conditions, we directly show how the LPS voltage and the doping gradient differ and link the physical effect of lower local resolution to the screening effect. Previously, the loss of local resolution was assumed to be only connected to the enlargement of the excess charge carrier distribution.

C-reactive protein (CRP), the prototype human acute phase protein, may be causally involved in various human diseases. As CRP has appeared much earlier in evolution than antibodies and nonetheless partly utilizes the same biological structures, it is likely that CRP has been the first antibody-like molecule in the evolution of the immune system. Like antibodies, CRP may cause autoimmune reactions in a variety of human pathologies. Consequently, therapeutic targeting of CRP may be of utmost interest in human medicine. Over the past two decades, however, pharmacological targeting of CRP has turned out to be extremely difficult. Currently, the easiest, most effective and clinically safest method to target CRP in humans may be the specific extracorporeal removal of CRP by selective apheresis. The latter has recently shown promising therapeutic effects, especially in acute myocardial infarction and COVID-19 pneumonia. This review summarizes the pros and cons of applying this novel technology to patients suffering from various diseases, with a focus on its use in cardiovascular medicine.

The crucible free growth of dislocation free respectively low defect single crystals on large diameter silicon seeds without using the common Dash technique was investigated. A promising concept to reach this aim was to reduce the thermal gradients and stresses. Therefore, a combination of RF- and MF heating, additionally to the standard FZ setup, was used by implementation of a further coil which is surrounding the 4 inch diameter seeds. The heat dissipation conditions, the growth velocity and the ratio between RF- and MF power were varied. Crystals were grown with a total length up to 120 mm. After 90 mm of single crystalline growth the crystals became polycrystalline. All grown crystals, independent of the seed structure or preparation procedure, developed a dislocation network during heating already before melting the seed surface and growth start. By noticeable reduction of the thermal stresses the single crystalline status could be maintained for a certain distance and an immediate transition to the polycrystalline growth could be avoided.

Residual stress is a key feature which has to be taken into account in all steps of fabrication and processing of semiconductor materials and devices. The photo-elastic microscope SIREX (Scanning Infrared Stress Explorer) measures the depolarization of the light of an infrared laser probe caused by stress-induced birefringence in the sample. Subsequently, a map visualizes the in-plane optical anisotropy induced by stress. Hence, the system is applied as non-destructive tool to map stress distributions with high lateral resolution (3µm) and highest possible stress sensitivity (0.1 kPa). The so-called multi-polarization analysis results in maps of the in-plane maximum shear stress magnitude Δσ and the direction of the principal stress components. These maps can reveal the local stress fields of buried defects and their alignment in distinctive crystallographic directions. The fields are usually at least one order of magnitude larger in extension than the related defects themselves. Examples of extended defect structures in different crystalline semiconductor materials are presented in this paper. The emphasis has been put on line-shaped structures such as slip lines and twins which are partly accompanied by either tensile or compressive point-like stress sources. These structures are showing model characteristics for developing formal procedures of data and image processing under industrial conditions.

We performed a numerical feasibility study of the application of the lateral photovoltage scanning (LPS) method to detect doping inhomogeneities (striations) in GaAs. Those striations follow the shape of the crystallization front, enabling its visualization. The obtained results allow direct validation of simulated temperature distributions in GaAs crystals. Our simulations revealed that realistic laser powers lead to LPS signals on the order of nanovolts. The actually used LPS measurement setup detects voltages at microvolt scale. So in order to build practical setups, one needs to either use better voltage detection devices or improve the method itself.

A numerical scheme was developed to compute the thermal and stress fields of the Czochralski process in a quasi-time dependent mode. The growth velocity was computed from the geometrical changes in melt and crystal due to pulling for every stage, for which the thermal and stress fields were computed by using the open source software Elmer. The method was applied to the Czochralski growth of Ge crystals by inductive heating. From a series of growth experiments, we chose one as a reference to check the validity of the scheme with respect to this Czochralski process. A good agreement both for the shapes of the melt/crystal interface at various time steps and the change in power consumption with process time was observed. �� 2019 by the authors. Licensee MDPI, Basel, Switzerland.

Dewetting is a ubiquitous phenomenon which can be applied to the laser synthesis of nanoparticles. A classical spinodal dewetting process takes place in four successive states, which differ from each other in their morphology. In this study all states are revealed by interaction of pulsed nanosecond UV laser light with thin gold layers with thicknesses between 1 nm and 10 nm on (100) silicon wafers. The specific morphologies of the dewetting states are discussed with particular emphasis on the state boundaries. The main parameter determining which state is formed is not the duration for which the gold remains liquid, but rather the input energy provided by the laser. This shows that each state transition has a separate measurable activation energy. The temperature during the nanosecond pulses and the duration during which the gold remains liquid was determined by simulation using the COMSOL Multiphysics® software package. Using these calculations, an accurate local temperature profile and its development over time was simulated. An analytical study of the morphologies and formed structures was performed using Minkowski measures. With aid of this tool, the laser induced structures were compared with thermally annealed samples, with perfectly ordered structures and with perfectly random structures. The results show that both, structures of the laser induced and the annealed samples, strongly resemble the perfectly ordered structures. This reveals a close relationship between these structures and suggests that the phenomenon under investigation is indeed a spinodal dewetting generated by an internal material wave function. The purposeful generation of these structures and the elucidation of the underlying mechanism of dewetting by short pulse lasers may assist the realisation of various technical elements such as nanowires in science and industry.

Patient: Male, 72-year-old Final Diagnosis: SARS-CoV-2 Symptoms: Dyspnea Medication: Standard Clinical Procedure: C-reactive protein apheresis Specialty: Immunology Objective: Unusual clinical course Background: C-reactive protein (CRP) plasma levels in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel viral disease, are surprisingly high. Pulmonary inflammation with subsequent fibrosis in SARS-CoV-2 infection is strongly accelerated. Recently, we have developed CRP apheresis to selectively remove CRP from human plasma. CRP may contribute to organ failure and pulmonary fibrosis in SARS-CoV-2 infection by CRP-mediated complement and macrophage activation. Case Report: A 72-year-old male patient at high risk was referred with dyspnea and fever. Polymerase chain reaction analysis of throat smear revealed SARS-CoV-2 infection. CRP levels were ∼200 mg/L. Two days after admission, CRP apheresis using the selective CRP adsorber (PentraSorb® CRP) was started. CRP apheresis was performed via peripheral venous access on days 2, 3, 4, and 5. Following a 2-day interruption, it was done via central venous access on days 7 and 8. Three days after admission the patient was transferred to the intensive care unit and intubated due to respiratory failure. Plasma CRP levels decreased by ∼50% with peripheral (processed blood plasma ≤6000 mL) and by ∼75% with central venous access (processed blood plasma ≤8000 mL), respectively. No apheresis-associated side effects were observed. After the 2-day interruption in apheresis, CRP levels rapidly re-increased (>400 mg/L) and the patient developed laboratory signs of multi-organ failure. When CRP apheresis was restarted, CRP levels and creatinine kinases (CK/CK-MB) declined again. Serum creatinine remained constant. Unfortunately, the patient died of respiratory failure on day 9 after admission. Conclusions: This is the first report on CRP apheresis in a SARS-CoV-2 patient. SARS-CoV-2 may cause multi-organ failure in part by inducing an excessive CRP-mediated autoimmune response of the ancient innate immune system.

High Purity Germanium (HPGe) crystals are indispensable for radiation detection and fundamental research. Among other applications they will be used in the Large Enriched Germanium Experiment for Neutrinoless double beta Decay (LEGEND) experiment for the search of neutrinoless double beta decay of 76 Ge. Ongoing research activities are done in collaboration with members of the existing GERDA experiment. In this context the Leibniz-Institut fur Kristallzuchtung (IKZ) is engaged in the development of HPGe Czochralski crystal growth including purification and characterization of the material. The Ge starting material is purified in a horizontal multi-zone furnace. Two inch Ge single crystals were grown by the Czochralski method and analyzed with respect to electrically active impurities by means of Hall-effect measurements and Photo-thermal Ionization Spectroscopy. The dislocation density is assessed by combining defect etching and optically microscopy imaging. Lateral Photovoltage Scanning is applied to visualize doping striations, which bear information on the shape of the solid–liquid phase boundary during growth.

My objective is to suggest a theoretical framework that integrates trust in dynamic production functions with semi-fixed production factors. Based on the input-output relation within the Theory of the Firm and a dispositive factor combining capital, labor, and know-how as factors of production, I propose that a high level of confidence in the capabilities of the company’s governing body enhances the adjustment process, resulting in more efficient production structures. I provide empirical results by using the model as a test with data from 34 formerly state-owned enterprises in Hungary and Poland during their transition period to privately owned companies.

During the last two years several new types of collaboration patterns within the supply chain have emerged. This development was highly influenced by the impact of e-business on the processes within companies, but also on transactions between the various partners of the supply chain.1

The original function of many Logistics Service Providers (LSP) has changed during the last decades. Originally freight forwarding companies started off with their typical freight forwarding activities: bundling several shipments of several customers, shipping them to their point of destination and debundling the goods before they are delivered to the final consignee. Over time the operating activities of freight forwarders have extended: while the traditional supply chain was highly fragmented, modern supply chains are characterized by a high degree of process integration. During this development freight forwarders increasingly have become Logistics Service Providers that manage the whole supply chain of globally active firms. This does not only involve the transportation of goods, but also the integration of complete supply chains, the planning, measurement, and controlling of flow of goods, information, and payment.