Mensch-Wolf-Beziehungen in den Alpen: Eine mehr-als-menschliche Geographie des Verbundenseins

Wölfe kehren in den Alpenraum zurück und sorgen insbesondere in der Land- und Jagdwirtschaft für dynamische Veränderungen. Basierend auf Ansätzen des klassischen Pragmatismus, des agentiellen Realismus und der Resonanztheorie identifiziert die Studie die Koexistenz von Menschen und Wölfen als leibliche Praxis, die beide Seiten wechselseitig hervorbringt. Anhand von ethnographischen Untersuchungen in den Schweizer Alpen können so neue Einsichten in Mensch-Wolf-Begegnungen, in transformative Erfahrungen sowie in Grenzziehungen gewährt werden. Verena Schröder stellt den menschlichen Kontrollanspruch über Tiere in Frage und liefert Denkanstöße für ein Miteinander, in dem Wölfe nicht als Bedrohung, sondern als Mit-Wesen gedacht werden und die Interessen aller Beteiligten Berücksichtigung finden

Kerfless exfoliated thin crystalline Si wafers with Al metallization layers for solar cells

We report on a kerfless exfoliation approach to further reduce the costs of crystalline silicon photovoltaics making use of evaporated Al as a double functional layer. The Al serves as the stress inducing element to drive the exfoliation process and can be maintained as a rear contacting layer in the solar cell after exfoliation. The 50-70 μm thick exfoliated Si layers show effective minority carrier lifetimes around 180 μs with diffusion lengths of 10 times the layer thickness. We analyze the thermo-mechanical properties of the Al layer by x-ray diffraction analysis and investigate its influence on the exfoliation process. We evaluate the approach for the implementation into solar cell production by determining processing limits and estimating cost advantages of a possible solar cell design route. The Al-Si bilayers are mechanically stable under processing conditions and exhibit a moderate cost savings potential of 3-36% compared to other c-Si cell concepts. © Materials Research Society 2015

Laser-welded interconnection of screen-printed Si solar cells

We demonstrate the laser welding of Al interconnects to the BSF rear-side of screen-printed two-side-contacted solar cells. The Al paste on the rear side of solar cell is laser-welded to an Al foil. This reduces the silver consumption of the solar cells by making silver pads on the rear side obsolete. Our proof-of-concept modules are free of laser damage. A 3-cell-module from 6" solar cells shows no change in fill factor within the statistical measurement uncertainty after artificial aging in 500 humidityfreeze cycles.German Ministry for the Environment, Nature Conservation, and Reactor Safety/0325192State of Lower Saxon

Thermomechanical Spalling of Epitaxially Grown Silicon from Porosified Substrates

We combine two kerfless approaches to unite advantages of both processes: the epitaxial layer transfer based on porous silicon (PSI process) and the lift-off of a thin silicon layer from a substrate via controlled spalling by a stress-inducing layer. For this, we deposit an Al stressor layer on top of an epitaxially grown silicon layer. A porous double layer underneath the epitaxial layer serves as determined breaking point. We directionally heat this sample stack and cool it afterwards for controlled spalling of the epitaxial layer from the substrate. We achieve a lift-off rate of 34 out of 36 detached samples. The porous silicon layer enables a smooth surface of the detached epitaxial layer and the remaining substrate. Compared to our standard spalling process the thickness variation of the detached layers is significantly reduced from ≤ 25 μm to less than 2 μm. Furthermore we show that the lifetime of the detached epitaxial layers does not suffer from the Al deposition and the lift-off process.Federal Ministry for Environment, Nature Conservation, and Nuclear Safety/FKZ 0325461State of Lower Saxon

Simultaneous Contacting and Interconnection of Passivated Emitter and Rear Solar Cells

The back end process of passivated emitter and rear cells (PERC) consists of at least one laser process and three screen-printing steps followed by the stringing and tabbing of the cells. To reduce the number of steps we have developed a process that metallizes the rear side including contact formation and simultaneously interconnects the cells. We attach an Al foil to an encapsulant layer. By laser processing we form 'laser-fired and bonding contacts' (LFBC) on the passivated rear side of the solar cells. The Al foil contacting the rear is laser welded to the Ag screen-printed front side metallization of the next cell and thus forms the cell interconnection. The laser contacts on the rear show a surface recombination velocity Scont for the contact regions of cm/s and a contact resistivity of 3.52 m?cm2. We present a first proof-of concept module combining the in-laminate Ag-Al laser welding and the LFBC reaching an efficiency of 18.4%. In accelerated aging test modules show no degradation (< 1% in efficiency) after 100 humidity-free cycles.Federal Ministry for Environment, Nature Conservation, and Nuclear Safety/FKZ/0325192State of Lower Saxon

Influence of Encapsulation Process Temperature on the Performance of Perovskite Mini Modules

Perovskite-on-silicon tandem solar cells are a promising candidate to significantly increase the efficiency of PV modules. Despite the fast research progress on material and solar cells aspects, there is still a lack of processes for an industrial module integration of these devices. One aspect hereby is the adaption of encapsulation materials and processes to the requirements of perovskite materials. Process temperatures of about 150 °C are necessary to use well proven, in silicon PV commonly applied encapsulation materials with a high reliability. However, perovskites start to decompose into their components at high temperatures. This limits the encapsulation process temperature, which in turn constraints the choice of encapsulation materials. This work presents an encapsulation process for methylammonium lead iodide (MAPhb) single junction perovskite solar cells (PSCs) with conventional production tools in glass-glass modules that serves as a model system for perovskite tandem applications. We evaluate the influence of the encapsulation process temperature between 120 °C and 160 °C on the performance of mini modules. The UV-absorbing encapsulation material is processable over the whole investigated temperature regime. We observe a difference in the IV-characteristics between the PSCs encapsulated in the temperature range of 120 °C - 140 °C to those processed at 160 °C. At lower encapsulation temperatures the IV-curves taken 1 h after encapsulation show a pronounced S-shape and no degradation of Foe. In contrast, the PSCs encapsulated at 160 °C exhibit a Foe decrease of up to 29% compared to the initial measurement shortly after PSC fabrication and no significant S-shape. Both, the S-shape that occurs at low encapsulation temperatures and the Foe loss after encapsulation at 160 °C, are no longer significant after one week of module storage under dark conditions. The presented encapsulation process therefore does not permanently damage the MAPbb PSCs even at a standard encapsulation temperature of 160 °C. To ensure long-term operation, we test the fabricated mini modules in a damp heat test at 85 °C and a relative humidity of 85%. We find no significant additional degradation caused by damp heat in 1250 h test duration compared to a reference module stored in ambient air

Computer-aided diagnosis through medical image retrieval in radiology.

Currently, radiologists face an excessive workload, which leads to high levels of fatigue, and consequently, to undesired diagnosis mistakes. Decision support systems can be used to prioritize and help radiologists making quicker decisions. In this sense, medical content-based image retrieval systems can be of extreme utility by providing well-curated similar examples. Nonetheless, most medical content-based image retrieval systems work by finding the most similar image, which is not equivalent to finding the most similar image in terms of disease and its severity. Here, we propose an interpretability-driven and an attention-driven medical image retrieval system. We conducted experiments in a large and publicly available dataset of chest radiographs with structured labels derived from free-text radiology reports (MIMIC-CXR-JPG). We evaluated the methods on two common conditions: pleural effusion and (potential) pneumonia. As ground-truth to perform the evaluation, query/test and catalogue images were classified and ordered by an experienced board-certified radiologist. For a profound and complete evaluation, additional radiologists also provided their rankings, which allowed us to infer inter-rater variability, and yield qualitative performance levels. Based on our ground-truth ranking, we also quantitatively evaluated the proposed approaches by computing the normalized Discounted Cumulative Gain (nDCG). We found that the Interpretability-guided approach outperforms the other state-of-the-art approaches and shows the best agreement with the most experienced radiologist. Furthermore, its performance lies within the observed inter-rater variability

Severe infections of Panton-Valentine leukocidin positive Staphylococcus aureus in children

Infections caused by Panton-Valentine leukocidin-positive Staphylococcus aureus (PVL-SA) mostly present as recurrent skin abscesses and furunculosis. However, life-threatening infections (eg, necrotizing pneumonia, necrotizing fasciitis, and osteomyelitis) caused by PVL-SA have also been reported.We assessed the clinical phenotype, frequency, clinical implications (surgery, length of treatment in hospitals/intensive care units, and antibiotic treatments), and potential preventability of severe PVL-SA infections in children.Total, 75 children treated for PVL-SA infections in our in- and outpatient units from 2012 to 2017 were included in this retrospective study.Ten out of 75 children contracted severe infections (PVL-methicillin resistant S aureus n = 4) including necrotizing pneumonia (n = 4), necrotizing fasciitis (n = 2), pyomyositis (n = 2; including 1 patient who also had pneumonia), mastoiditis with cerebellitis (n = 1), preorbital cellulitis (n = 1), and recurrent deep furunculosis in an immunosuppressed patient (n = 1). Specific complications of PVL-SA infections were venous thrombosis (n = 2), sepsis (n = 5), respiratory failure (n = 5), and acute respiratory distress syndrome (n = 3). The median duration of hospital stay was 14 days (range 5-52 days). In 6 out of 10 patients a history suggestive for PVL-SA colonization in the patient or close family members before hospital admission was identified.PVL-SA causes severe to life-threatening infections requiring lengthy treatments in hospital in a substantial percentage of symptomatic PVL-SA colonized children. More than 50% of severe infections might be prevented by prompt testing for PVL-SA in individuals with a history of abscesses or furunculosis, followed by decolonization measures