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To identify genetic variants associated with head circumference in infancy, we performed a meta-analysis of seven genome-wide association studies (GWAS) (N = 10,768 individuals of European ancestry enrolled in pregnancy and/or birth cohorts) and followed up three lead signals in six replication studies (combined N = 19,089). rs7980687 on chromosome 12q24 (P = 8.1 x 10(-9)) and rs1042725 on chromosome 12q15 (P = 2.8 x 10(-10)) were robustly associated with head circumference in infancy. Although these loci have previously been associated with adult height(1), their effects on infant head circumference were largely independent of height (P = 3.8 x 10(-7) for rs7980687 and P = 1.3 x 10(-7) for rs1042725 after adjustment for infant height). A third signal, rs11655470 on chromosome 17q21, showed suggestive evidence of association with head circumference (P = 3.9 x 10(-6)). SNPs correlated to the 17q21 signal have shown genome-wide association with adult intracranial volume(2), Parkinson's disease and other neurodegenerative diseases(3-5), indicating that a common genetic variant in this region might link early brain growth with neurological disease in later life.
The implementation of shape-memory effects (SME) in polymeric micro- or nano-objects currently relies on the application of indirect macroscopic manipulation techniques, for example, stretchable molds or phantoms, to ensembles of small objects. Here, we introduce a method capable of the controlled manipulation and SME quantification of individual micro- and nano-objects in analogy to macroscopic thermomechanical test procedures. An atomic force microscope was utilized to address individual electro-spun poly(ether urethane) (PEU) micro- or nanowires freely suspended between two micropillars on a micro-structured silicon substrate. In this way, programming strains of 10 +/- 1% or 21 +/- 1% were realized, which could be successfully fixed. An almost complete restoration of the original free-suspended shape during heating confirmed the excellent shape-memory performance of the PEU wires. Apparent recovery stresses of sigma(max,app)=1.2 +/- 0.1 and 33.3 +/- 0.1MPa were obtained for a single microwire and nanowire, respectively. The universal AFM test platform described here enables the implementation and quantification of a thermomechanically induced function for individual polymeric micro- and nanosystems.
HPI Future SOC Lab
(2015)
Das Future SOC Lab am HPI ist eine Kooperation des Hasso-Plattner-Instituts mit verschiedenen Industriepartnern. Seine Aufgabe ist die Ermöglichung und Förderung des Austausches zwischen Forschungsgemeinschaft und Industrie.
Am Lab wird interessierten Wissenschaftlern eine Infrastruktur von neuester Hard- und Software kostenfrei für Forschungszwecke zur Verfügung gestellt. Dazu zählen teilweise noch nicht am Markt verfügbare Technologien, die im normalen Hochschulbereich in der Regel nicht zu finanzieren wären, bspw. Server mit bis zu 64 Cores und 2 TB Hauptspeicher. Diese Angebote richten sich insbesondere an Wissenschaftler in den Gebieten Informatik und Wirtschaftsinformatik. Einige der Schwerpunkte sind Cloud Computing, Parallelisierung und In-Memory Technologien.
In diesem Technischen Bericht werden die Ergebnisse der Forschungsprojekte des Jahres 2015 vorgestellt. Ausgewählte Projekte stellten ihre Ergebnisse am 15. April 2015 und 4. November 2015 im Rahmen der Future SOC Lab Tag Veranstaltungen vor.
Ecologists increasingly use spatial statistics to study vegetation patterns. Mostly, however, these techniques are applied in a purely descriptive fashion without a priori statements on the pattern characteristics expected. We formulated such a priori predictions in a study of spatial pattern in a semi-arid Karoo shrubland, South Africa. Both seed dispersal and root competition have been discussed as processes shaping the spatial structure of this community. If either of the two processes dominates pattern formation, patterns within and between shrub functional groups are expected to show distinct deviations from null models. We predicted the type and scale of these deviations and compared predicted to observed pattern characteristics. As predicted by the seed dispersal hypothesis, small-scale co-occurrence within and between groups of colonisers and successors was increased as compared to complete spatially random arrangement of shrubs. The root competition predictions, however, were not met as shrubs of similar rooting depth co- occurred more frequently than expected under random shrub arrangement. Since the distribution of rooting groups to the given shrub locations also failed to match the root competition predictions, there was little evidence for dominance of root competition in pattern formation. Although other processes may contribute to small-scale plant co-occurrence, the sufficient and most parsimonious explanation for the observed pattern is that its formation was dominated by seed dispersal. To characterise point patterns we applied both cumulative (uni- and bivariate K-function) and local (pair- and mark-correlation function) techniques. Based on our results we recommend that future studies of vegetation patterns include local characteristics as they independently describe a pattern at different scales and can be easily related to processes changing with interplant distance in a predictable fashion.
The optimized design of multilayer-coated blazed gratings (MLBG) for high-flux tender X-ray monochromators was systematically studied by numerical simulations. The resulting correlation between the multilayer d-spacing and grating blaze angle significantly deviated from the one predicted by conventional equations. Three high line density gratings with different blaze angles were fabricated and coated by the same Cr/C multilayer. The MLBG with an optimal blaze angle of 1.0 degrees showed a record efficiency reaching 60% at 3.1 keV and 4.1 keV. The measured efficiencies of all three gratings were consistent with calculated results proving the validity of the numerical simulation and indicating a more rigorous way to design the optimal MLBG structure. Published by The Optical Society under the terms of the Creative Commons Attribution 4.0 License.
GrassPlot is a collaborative vegetation-plot database organised by the Eurasian Dry Grassland Group (EDGG) and listed in the Global Index of Vegetation-Plot Databases (GIVD ID EU-00-003). GrassPlot collects plot records (releves) from grasslands and other open habitats of the Palaearctic biogeographic realm. It focuses on precisely delimited plots of eight standard grain sizes (0.0001; 0.001;... 1,000 m(2)) and on nested-plot series with at least four different grain sizes. The usage of GrassPlot is regulated through Bylaws that intend to balance the interests of data contributors and data users. The current version (v. 1.00) contains data for approximately 170,000 plots of different sizes and 2,800 nested-plot series. The key components are richness data and metadata. However, most included datasets also encompass compositional data. About 14,000 plots have near-complete records of terricolous bryophytes and lichens in addition to vascular plants. At present, GrassPlot contains data from 36 countries throughout the Palaearctic, spread across elevational gradients and major grassland types. GrassPlot with its multi-scale and multi-taxon focus complements the larger international vegetationplot databases, such as the European Vegetation Archive (EVA) and the global database " sPlot". Its main aim is to facilitate studies on the scale-and taxon-dependency of biodiversity patterns and drivers along macroecological gradients. GrassPlot is a dynamic database and will expand through new data collection coordinated by the elected Governing Board. We invite researchers with suitable data to join GrassPlot. Researchers with project ideas addressable with GrassPlot data are welcome to submit proposals to the Governing Board.
Neisseria gonorrhoeae is one of the most prevalent sexually transmitted diseases worldwide with more than 100 million new infections per year. A lack of intense research over the last decades and increasing resistances to the recommended antibiotics call for a better understanding of gonococcal infection, fast diagnostics and therapeutic measures against N. gonorrhoeae. Therefore, the aim of this work was to identify novel immunogenic proteins as a first step to advance those unresolved problems. For the identification of immunogenic proteins, pHORF oligopeptide phage display libraries of the entire N. gonorrhoeae genome were constructed. Several immunogenic oligopeptides were identified using polyclonal rabbit antibodies against N. gonorrhoeae. Corresponding full-length proteins of the identified oligopeptides were expressed and their immunogenic character was verified by ELISA. The immunogenic character of six proteins was identified for the first time. Additional 13 proteins were verified as immunogenic proteins in N. gonorrhoeae.
Neisseria gonorrhoeae is the causative organism of gonorrhoea, a sexually transmitted disease that globally accounts for an estimated 80 to 100 million new infections per year. Increasing resistances to all common antibiotics used for N. gonorrhoeae treatment pose the risk of an untreatable disease. Further knowledge of ways of infection and host immune response are needed to understand the pathogen-host interaction and to discover new treatment alternatives against this disease. Therefore, detailed information about immunogenic proteins and their properties like epitope sites could advance further research in this area. In this work, we investigated immunogenic proteins of N. gonorrhoeae for linear epitopes by microarrays. Dominant linear epitopes were identified for eleven of the nineteen investigated proteins with three polyclonal rabbit antibodies from different immunisations. Identified linear epitopes were further examined for non-specific binding with antibodies to Escherichia coli and the closely related pathogen Neisseria meningitidis. On top of that, amino acids crucial for the antibody epitope binding were detected by microarray based alanine scans.
Peptide microarrays displaying biologically active small synthetic peptides in a high-density format provide an attractive technology to probe complex samples for the presence and/or function of protein analytes. We present a new approach for manufacturing functional peptide microarrays for molecular immune diagnostics. Our method relies on the efficiency of site-specific solution-phase coupling of biotinylated synthetic peptides to NeutrAvidin (NA) and localized microdispensing of peptide-NA-complexes onto activated glass surfaces. Antibodies are captured in a sandwich manner between surface immobilized peptide probes and fluorescence-labeled secondary antibodies. Our work includes a total of 54 peptides derived from immunodominant linear epitopes of the T7 phage capsid protein, Herpes simplex virus glycoprotein D, c-myc protein, and three domains of the Human coronavirus polymerase polyprotein and their cognate mAbs. By using spacer molecules of different type and length for NA-mediated peptide presentation, we show that the incorporation of a minimum spacer length is imperative for antibody binding, whereas the peptide immobilization direction has only secondary importance for antibody affinity and binding. We further demonstrate that the peptide array is capable of detecting low-picomolar concentrations of mAbs in buffered solutions and diluted human serum with high specificity
Peptide microarrays with site-specifically immobilized synthetic peptides for antibody diagnostics
(2006)
Peptide microarrays bear the potential to discover molecular recognition events on protein level, particularly in the field of molecular immunology, in a manner and with an efficiency comparable to the performance of DNA microarrays. We developed a novel peptide microarray platform for the detection of antibodies in liquid samples. The system comprises site-specific solution phase coupling of biotinylated peptides to NeutrAvidin, localized microdispensing of peptide-NeutrAvidin conjugates onto activated glass slides and a fluorescence immuno sandwich assay format for antibody capture and detection. Our work includes synthetic peptides deduced from amino acid sequences of immunodominant linear epitopes, such as the T7 phage capsid protein, Herpes simplex virus glycoprotein D, c-myc protein and three domains of the Human coronavirus 229E polymerase polyprotein. We demonstrate that our method produces peptide arrays with excellent spot morphology which are capable of specific and sensitive detection of monoclonal antibodies from fluid samples.
Neisseria gonorrhoeae is one of the most prevalent sexually transmitted diseases worldwide with more than 100 million new infections per year. A lack of intense research over the last decades and increasing resistances to the recommended antibiotics call for a better understanding of gonococcal infection, fast diagnostics and therapeutic measures against N. gonorrhoeae. Therefore, the aim of this work was to identify novel immunogenic proteins as a first step to advance those unresolved problems. For the identification of immunogenic proteins, pHORF oligopeptide phage display libraries of the entire N. gonorrhoeae genome were constructed. Several immunogenic oligopeptides were identified using polyclonal rabbit antibodies against N. gonorrhoeae. Corresponding full-length proteins of the identified oligopeptides were expressed and their immunogenic character was verified by ELISA. The immunogenic character of six proteins was identified for the first time. Additional 13 proteins were verified as immunogenic proteins in N. gonorrhoeae.
Modern natural hazards research requires dealing with several uncertainties that arise from limited process knowledge, measurement errors, censored and incomplete observations, and the intrinsic randomness of the governing processes. Nevertheless, deterministic analyses are still widely used in quantitative hazard assessments despite the pitfall of misestimating the hazard and any ensuing risks.
In this paper we show that Bayesian networks offer a flexible framework for capturing and expressing a broad range of uncertainties encountered in natural hazard assessments. Although Bayesian networks are well studied in theory, their application to real-world data is far from straightforward, and requires specific tailoring and adaptation of existing algorithms. We offer suggestions as how to tackle frequently arising problems in this context and mainly concentrate on the handling of continuous variables, incomplete data sets, and the interaction of both. By way of three case studies from earthquake, flood, and landslide research, we demonstrate the method of data-driven Bayesian network learning, and showcase the flexibility, applicability, and benefits of this approach.
Our results offer fresh and partly counterintuitive insights into well-studied multivariate problems of earthquake-induced ground motion prediction, accurate flood damage quantification, and spatially explicit landslide prediction at the regional scale. In particular, we highlight how Bayesian networks help to express information flow and independence assumptions between candidate predictors. Such knowledge is pivotal in providing scientists and decision makers with well-informed strategies for selecting adequate predictor variables for quantitative natural hazard assessments.
Interacting services play a key role to realize business process integration among different business partners by means of electronic message exchange. In order to provide seamless integration of these services, the messages exchanged as well as their dependencies must be well-defined. Service choreographies are a means to describe the allowed conversations. This article presents a requirements framework for service choreography languages, along which existing choreography languages are assessed. The requirements framework provides the basis for introducing the language BPEL4Chor, which extends the industry standard WS-BPEL with choreography-specific concepts. A validation is provided and integration with executable service orchestrations is discussed.
Effects of isoflavones on estrogen sensitive tissues are discussed controversially This study was designed to investigate tissue specific effects of an isoflavone exposure through different periods of life in female Wistar rats and to compare the effects of genistein (GEN) to those of mixed dietary isoflavones, GEN and daidzein (DAI). One group received an isoflavone-free diet (IDD). another was fed an isoflavone-rich diet (IRD) and the third group an IDD supplemented with GEN (GEN(d)) prior to mating. throughout pregnancy and up to weaning The offspring were kept on the respective diets during growth. puberty and adulthood The weight of the uterus, the height of the uterine and vaginal epithelium, the bone mineral density of the tibia, and the expression of the estrogen sensitive gene CaBP9K in the liver were determined. At d21, the uterine weight, the uterine epithelium and the expression of CaBP9K in the liver were significantly stimulated in GEN(d) animals compared to IDD and IRD Interestingly, bone mineral density was increased in GEN(d) and in IRD animals Around puberty (d50) neither uterine wet weights nor trabecular bone density differed significantly among the isoflavone groups and the IDD control. At d80 nosignificant differences in uterine weight were observed among IDD. GEN(d) and IRD animals. However, bone mineral density was increased in GEN(d) and IRD animals In summary, Our results demonstrate that lifelong dietary exposure to isoflavones can affect estrogen sensitive tissues, apparently in a tissue selective manner With respect to health risk and benefit our data indicate that an increased bone mineral density can be achieved by lifelong exposure to an IRD. which, in contrast to GEN supplementation, does not seem to stimulate the proliferation of the uterine epithelium
The teleost v1r-related ora genes are a small, highly conserved olfactory receptor gene family of only six genes, whose direct orthologues can be identified in lineages as far as that of cartilaginous fish. However, no ligands for fish olfactory receptor class A related genes (ORA) had been uncovered so far. Here we have deorphanized the ORA1 receptor using heterologous expression and calcium imaging. We report that zebrafish ORA1 recognizes with high specificity and sensitivity 4-hydroxyphenylacetic acid. The carboxyl group of this compound is required in a particular distance from the aromatic ring, whereas the hydroxyl group in the para-position is not essential, but strongly enhances the binding efficacy. Low concentrations of 4-hydroxyphenylacetic acid elicit increases in oviposition frequency in zebrafish mating pairs. This effect is abolished by naris closure. We hypothesize that 4-hydroxyphenylacetic acid might function as a pheromone for reproductive behavior in zebrafish. ORA1 is ancestral to mammalian V1Rs, and its putative function as pheromone receptor is reminiscent of the role of several mammalian V1Rs as pheromone receptors.
East African paleoenvironments are highly variable, marked by extreme fluctuations in moisture availability, which has far-reaching implications for the origin, evolution and dispersal of Homo sapiens in and beyond the region. This paper presents results from a pilot core from the Chew Bahir basin in southern Ethiopia that records the climatic history of the past 45 ka, with emphasis on the African Humid Period (AHP, similar to 15-5 ka calBP). Geochemical, physical and biological indicators show that Chew Bahir responded to climatic fluctuations on millennial to centennial timescales, and to the precessional cycle, since the Last Glacial Maximum. Potassium content of the sediment appears to be a reliable proxy for aridity, showing that Chew Bahir reacted to the insolation-controlled humidity increase of the AHP with a remarkably abrupt onset and a gradual termination, framing a sharply defined arid phase (similar to 12.8-11.6 ka calBP) corresponding to the Younger Dryas chronozone. The Chew Bahir record correlates well with low- and high-latitude paleoclimate records, demonstrating that the site responded to regional and global climate changes.
Rotational Barriers of Substituted BIPHEP Ligands: A Comparative Experimental and Theoretical Study
(2016)
The interconversion barriers of 14 different 3,3- and 5,5-disubstituted tropos BIPHEP [2,2-bis(diphenylphosphino)-1,1-biphenyl] and BIPHEP(O) [2,2-bis(diphenylphosphoryl)-1,1-biphenyl] ligands were investigated by enantioselective dynamic high performance liquid chromatography (DHPLC) and DFT calculations using the B3LYP/6-31G* and M06-2X/6-31G* levels of theory. The experimentally determined enantiomerization barriers varied from 86.8 to 101.4 kJmol(-1) and were found to be in excellent agreement with the calculated data. The root-mean-square deviations are 7.3 kJmol(-1) for the B3LYP functional and 11.3 kJmol(-1) for the M06-2X method.
Militärische Eliten gehören traditionell zum Kanon militärgeschichtlicher Forschung. Der zu Recht geforderte Perspektivenwechsel innerhalb der Disziplin nach einer Militärgeschichte von „unten“, die auch die einfachen Soldaten in den Blick nimmt, hat dazu geführt, dass den Eliten lange Zeit wenig Aufmerksamkeit geschenkt wurde. Erst im Rahmen der „neuen Militärgeschichte“ geraten nun seit einigen Jahren die Eliten wieder stärker in den Fokus der Forschung. Gleichwohl ist ein befriedigender Erkenntnisstand für dieses klassische Feld nicht festzustellen. Noch immer klaffen in der deutschen Forschung, vor allem im Vergleich zu Frankreich und dem angelsächsischen Sprachraum, eklatante Lücken, die nur durch sozialgeschichtliche Grundlagenforschung und kulturgeschichtlich ausgerichtete Mikrostudien zu füllen sind. Die hier versammelten Analysen, die sich mit den militärischen Eliten Preußens, Bayerns, der weiteren Reichsterritorien sowie Schwedens und des Osmanischen Reiches beschäftigen, wollen einen Beitrag zur Schließung dieser Forschungslücken leisten und zudem Fragen und Perspektiven, die sich durch den „cultural turn“ innerhalb der Geschichtswissenschaft eröffnet haben, für diese Thematik ausloten.
Global emissions scenarios play a critical role in the assessment of strategies to mitigate climate change. The current scenarios, however, are criticized because they feature strategies with pronounced overshoot of the global temperature goal, requiring a long-term repair phase to draw temperatures down again through net-negative emissions. Some impacts might not be reversible. Hence, we explore a new set of net-zero CO2 emissions scenarios with limited overshoot. We show that upfront investments are needed in the near term for limiting temperature overshoot but that these would bring long-term economic gains. Our study further identifies alternative configurations of net-zero CO2 emissions systems and the roles of different sectors and regions for balancing sources and sinks. Even without net-negative emissions, CO2 removal is important for accelerating near-term reductions and for providing an anthropogenic sink that can offset the residual emissions in sectors that are hard to abate.
Inhalt:
Alexander von Humboldt-Forschungsstelle: Ingo Schwarz zum 65. Geburtstag
Ottmar Ette: Findung und Erfindung einer Leserschaft. Neuere Editionsprojekte zu Alexander von Humboldt als Grundlage und Herausforderung künftigen Forschens
Eberhard Knobloch: Alexandre de Humboldt et le Marquis de Laplace
Oliver Schwarz: Alexander von Humboldt als astronomischer Arbeiter, Diskussionspartner und Ideengeber
Petra Werner: Innenwelten und bleiche Gärten. Alexander von Humboldt untertage und in der Caripe-Höhle
Christian Suckow: Alexander von Humboldt in Ust’-Kamenogorsk
Anne Jobst: Neue Briefe Christian Gottfried Ehrenbergs an Alexander von Humboldt
Thomas Schmuck: Humboldt, Baer und die Evolution
Manfred Ringmacher: Zwei Briefe auf Guaraní in Alexander von Humboldts Handschrift
Ute Tintemann: Julius Klaproths Mithridates-Projekt, Alexander von Humboldt und das Verlagshaus Cotta
Ulrike Leitner: „Ja! Wenn Berlin Bonn wäre!“ Friedrich Rückerts Berufung nach Berlin
Frank Holl: „Zur Freiheit bestimmt“ – Alexander von Humboldts Blick auf die Kulturen der Welt
Sebastian Panwitz: Das Humboldt-Mendelssohn-Haus Jägerstraße 22. Ein Quellenfund
Laura Péaud: Du Mexique à l‘Oural : l‘expertise humboldtienne au service du politique
Bärbel Holtz: „Cicerone“ des Königs? Alexander von Humboldt und Friedrich Wilhelm III.
Menso Folkerts: Ein unerwartetes Zusammentreffen in Sanssouci. Alexander von Humboldt und Karl Ludwig Hencke an der Tafel Friedrich Wilhelms IV.
Ulrich Päßler: Preußens Mann in Washington. Fünf Briefe Friedrich von Gerolts an Alexander von Humboldt (1858/1859)
Bill Roba: German-Iowan Strategies in Celebrating the Centennial of Alexander von Humboldt’s Birth
Regina Mikosch: Ingo Schwarz‘ Veröffentlichungen zur Alexander von Humboldt
Über die Autoren
Cloning and characterization of a single chain antibody to glucose oxidase from a murine hybridoma
(2007)
Glucose oxidase (GOD) is an oxidoreductase catalyzing the reaction of glucose and oxygen to peroxide and gluconolacton (EC 1.1.3.4.). GOD is a widely used enzyme in biotechnology. Therefore the production of monoclonal antibodies and antibody fragments to GOD are of interest in bioanalytics and even tumor therapy. We describe here the generation of a panel of monoclonal antibodies to native and heat inactivated GOD. One of the hybridomas, E13BC8, was used for cloning of a single chain antibody (scFv). This scFv was expressed in Escherichia coli XL1-blue with the help of the vector system pOPE101. The scFv was isolated from the periplasmic fraction and detected by western blotting. It reacts specifically with soluble active GOD but does not recognize denatured GOD adsorbed to the solid phase. The same binding properties were also found for the monoclonal antibody E13BC8.
The northern edge of the western central Tien Shan range is bounded by the Issyk-Ata fault situated south of Bishkek, the capital of Kyrgyzstan. Contraction in this thick-skinned orogen occurs with low-strain accumulation and long earthquake recurrence intervals. In the nineteenth to twentieth centuries, a sequence of large earthquakes with magnitudes between 6.9 and 8 affected the northern Tien Shan but left nearly the entire extent of the Issyk-Ata fault unruptured. Here, the only known historic earthquake ruptured in A.D. 1885 (M6.9) along the western end of the Issyk-Ata fault. Because earthquakes in low-strain regions often tend to cluster in time and may promote failure along nearby structures, the earthquake history of the northern Tien Shan represents an exceptional structural setting for studying fault behavior affected by an intraplate earthquake sequence. We present a paleoseismological study from one site (Belek) along the Issyk-Ata fault located east of the A.D. 1885 epicentral area. Our analysis combines a range of tools, including photogrammetry, differential Global Positioning System, 3D visualization, and age modeling with different dating methods (infrared stimulated luminescence, radiocarbon, U-series) to improve the reliability of an event chronology for the trench stratigraphy and fault geometry. We were able to distinguish three different surfacerupturing paleoearthquakes; these affected the area before 10.5 +/- 1.1 cal ka B.P., at similar to 5.6 +/- 1.0 cal ka B.P., and at similar to 630 +/- 100 cal B.P., respectively. Associated paleomagnitudes for the last two earthquakes range between M6.7 and 7.4, with a cumulative slip rate of 0.7 +/- 0.32 mm/yr. We did not find evidence for the A.D. 1885 event at Belek. Our study yielded two main overall results: first, it extends the regional historic and paleoseismic record; second, the documented rupture events along the Issyk-Ata fault suggest that this fault was not affected in its entirety; instead, these events indicate segmented rupture behavior.
Biological responses to climate change have been widely documented across taxa and regions, but it remains unclear whether species are maintaining a good match between phenotype and environment, i.e. whether observed trait changes are adaptive. Here we reviewed 10,090 abstracts and extracted data from 71 studies reported in 58 relevant publications, to assess quantitatively whether phenotypic trait changes associated with climate change are adaptive in animals. A meta-analysis focussing on birds, the taxon best represented in our dataset, suggests that global warming has not systematically affected morphological traits, but has advanced phenological traits. We demonstrate that these advances are adaptive for some species, but imperfect as evidenced by the observed consistent selection for earlier timing. Application of a theoretical model indicates that the evolutionary load imposed by incomplete adaptive responses to ongoing climate change may already be threatening the persistence of species.
We demonstrate a recycling system for synthetic nicotinamide cofactor analogues using a soluble hydrogenase with turnover number of >1000 for reduction of the cofactor analogues by H-2.
Coupling this system to an ene reductase, we show quantitative conversion of N-ethylmaleimide to N-ethylsuccinimide.
The biocatalyst system retained >50% activity after 7 h.
Investigations with frequency domain photon density waves allow elucidation of absorption and scattering properties of turbid media. The temporal and spatial propagation of intensity modulated light with frequencies up to more than 1 GHz can be described by the P1 approximation to the Boltzmann transport equation. In this study, we establish requirements for the appropriate choice of turbid model media and characterize mixtures of isosulfan blue as absorber and polystyrene beads as scatterer. For these model media, the independent determination of absorption and reduced scattering coefficients over large absorber and scatterer concentration ranges is demonstrated with a frequency domain photon density wave spectrometer employing intensity and phase measurements at various modulation frequencies.
Diffuse reflectance measurements and photon migration studies with near infrared (NIR) diode lasers were employed to elucidate experimental methods for determining absorption and scattering coefficients and species concentrations in highly scattering solutions. Applicability of theoretical approaches were established by investigating model systems with absorbing (e.g. ink, malachite green) and scattering (e.g. milk powder, caolinit) species in aqueous solution. While diffuse reflectance measurements practically requires calibration procedures, photon migration studies allow quantitative determination of absorption and scattering coefficients of turbid solutions consistent with absorptions coefficients obtained from Lambert-Beer's law. Furthermore, NIR absorption spectra of water, chlorinated hydrocarbons (chloroform, 1,2-dichloroethane, trichloroethene) and of various sugars ($alpha$-D-glucose, sucrose, maltose) are discussed. Spectral variations of NIR water absorption with temperature and solvents are exammined. Exemplary, NIR diode laser detection of water in acetone/water mixtures is performed.
Electronic intensity and frequency modulation of diode lasers enables new perspectives for highly sensitive analytical in-situ techniques. For analyis of "heterogeneous" media, which may consist of coexisting gaseous, liquid, and solid phases and often show multiple light scattering, non-invasive techniques with outstanding performance characteristics can be developed. Analysis of photon density waves launched by intensity-modulated lasers provide an elegant way for the determination of absorption and scattering coefficients of multiple scattering media. The absorption coefficient can be used for qualitative and quantitative analysis of chemical constituents (which absorb in the range of the laser wavelengths). The scattering coefficient allows characterization of physical and morphological properties of the sample. In the current work, applicability of appropriate radiation transport models was investigated with simple light scattering solutions and compared with results obtained from the treatment according to the theory of Kubelka and Munk. Measurements of human blood samples are discussed. A new method for determination of water vapor partial pressure in a polyurethane foam with a frequency-modulated external cavity diode laser is discussed.
Multijunction solar cells can overcome the fundamental efficiency limits of single-junction devices. The bandgap tunability of metal halide perovskite solar cells renders them attractive for multijunction architectures(1). Combinations with silicon and copper indium gallium selenide (CIGS), as well as all-perovskite tandem cells, have been reported(2-5). Meanwhile, narrow-gap non-fullerene acceptors have unlocked skyrocketing efficiencies for organic solar cells(6,7). Organic and perovskite semiconductors are an attractive combination, sharing similar processing technologies. Currently, perovskite-organic tandems show subpar efficiencies and are limited by the low open-circuit voltage (V-oc) of wide-gap perovskite cells(8) and losses introduced by the interconnect between the subcells(9,10). Here we demonstrate perovskite-organic tandem cells with an efficiency of 24.0 per cent (certified 23.1 per cent) and a high V-oc of 2.15 volts. Optimized charge extraction layers afford perovskite subcells with an outstanding combination of high V-oc and fill factor. The organic subcells provide a high external quantum efficiency in the near-infrared and, in contrast to paradigmatic concerns about limited photostability of non-fullerene cells(11), show an outstanding operational stability if excitons are predominantly generated on the non-fullerene acceptor, which is the case in our tandems. The subcells are connected by an ultrathin (approximately 1.5 nanometres) metal-like indium oxide layer with unprecedented low optical/electrical losses. This work sets a milestone for perovskite-organic tandems, which outperform the best p-i-n perovskite single junctions(12) and are on a par with perovskite-CIGS and all-perovskite multijunctions(13).
The “HPI Future SOC Lab” is a cooperation of the Hasso Plattner Institute (HPI) and industry partners. Its mission is to enable and promote exchange and interaction between the research community and the industry partners.
The HPI Future SOC Lab provides researchers with free of charge access to a complete infrastructure of state of the art hard and software. This infrastructure includes components, which might be too expensive for an ordinary research environment, such as servers with up to 64 cores and 2 TB main memory. The offerings address researchers particularly from but not limited to the areas of computer science and business information systems. Main areas of research include cloud computing, parallelization, and In-Memory technologies.
This technical report presents results of research projects executed in 2019. Selected projects have presented their results on April 9th and November 12th 2019 at the Future SOC Lab Day events.