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We discuss achieving attosecond-level temporal resolution via Hong-Ou-Mandel interferometry using highly non-degenerate frequency-entangled photons. This approach offers robustness against dispersion and loss, and facilitates novel sensing schemes in regimes inaccessible by existing interferometers.

TheBunyaviralesorder contains several emerging viruses with high epidemic potential, including Severe fever with thrombocytopenia syndrome virus (SFTSV). The lack of medical countermeasures, such as vaccines and antivirals, is a limiting factor for the containment of any virus outbreak. To develop such antivirals a profound understanding of the viral replication process is essential. The L protein of bunyaviruses is a multi-functional and multi-domain protein performing both virus transcription and genome replication and, therefore, would be an ideal drug target. We established expression and purification procedures for the full-length L protein of SFTSV. By combining single-particle electron-cryo microscopy and X-ray crystallography, we obtained 3D models covering ∼70% of the SFTSV L protein in the apo-conformation including the polymerase core region, the endonuclease and the cap-binding domain. We compared this first L structure of thePhenuiviridaefamily to the structures of La Crosse peribunyavirus L protein and influenza orthomyxovirus polymerase. Together with a comprehensive biochemical characterization of the distinct functions of SFTSV L protein, this work provides a solid framework for future structural and functional studies of L protein-RNA interactions and the development of antiviral strategies against this group of emerging human pathogens.

We can envision an eventual global multi-node quantum network, with hubs located around the planet. This, however, is still a far reach from current state of the art. Here we discuss some of our approaches to bridge the gap. Specifically, we are pursuing airborne and satellite-based free-space quantum communication. Free-space platforms naturally lend themselves to reconfiguration - likely required by a future quantum-secure network -- as nodes may be easily moved/reoriented to target new nodes. We are implementing a multi-copter drone-based quantum cryptography link, including fast, high-resolution optical stabilization; compact, independent sources; and lightweight single-photon detection. Having access to an agile, reconfigurable QKD networking system will enable quantum cryptography to reach applications prohibited by current approaches, such as temporary networks in seaborne, urban, or even battlefield situations. By using transmitters and receivers at higher altitudes, deleterious effects weather events like fog and turbulence can be mitigated. At longer scale, we are pursuing a quantum link from the International Space Station to earth, which will use hyperentanglement to enable a variety of advanced quantum communication protocols, including multi-bit-per-photon key distribution and "superdense" teleportation. With our table-top experiment we have investigated the effects of loss and turbulence, and demonstrated a system to compensate for the otherwise devastating effect of the Doppler effect from the rapidly moving ISS platform.

As optical quantum information processing protocols and experiments become increasingly more complex, integrated optics provide a small and robust alternative to traditional bulk optics. Specifically, waveguide technology allows for the creation of bright single-photon sources based on the fact that photon pairs can be created at any location along the waveguide. For our goals, we are working on the characterization of a highly nondegenerate Spontaneous Parametric Down-Conversion (SPDC) waveguide source on a periodically poled KTP (PPKTP) crystal. Our current waveguide source uses type-II phase-matching to create collinear signal and idler photons at 1550 nm and 810 nm, respectively, with the promise of generating simultaneous time-bin and polarization entanglement in future iterations. Our intended source application is for use in quantum key distribution and superdense teleportation protocols between a space platform and collection telescopes on Earth.

Human myxovirus resistance protein B (hMXB) is a restriction factor of HIV-1 that also inhibits a variety of retroviruses. However, hMXB is not antiviral against equine infectious anemia virus (EIAV). We show here that equine MX2 (eMX2) potently restricts EIAV in vitro. Additionally, eMX2 inhibits HIV-1 and other lentiviruses, including murine leukemia virus. Previously, it was reported that hMXB repression is reduced in hMXB Δ1-25, but not in GTP-binding mutant K131A and GTP-hydrolysis mutant T151A. In contrast to this phenomenon, our study indicates that eMX2 restriction is not diminished in eMX2 Δ1-25, but is in eMX2 K127A and T147A, which correspond to hMXB K131A and T151A, respectively. Thus, eMX2 may inhibit retroviral replication by a novel mechanism that differs from that of hMXB.

Superdense Teleportation (SDT) is a suitable protocol to choose for an advanced demonstration of quantum communication in space. We have taken further steps towards the realization of SDT in such an endeavor. Our system uses polarization and time-bin hyperentanglement via non-degenerate spontaneous parametric downconversion to implement SDT of 4-dimensional equimodular states. Previously, we have shown high fidelity (>90p) SDT implementation and the feasibility to perform SDT on an orbiting platform by correcting the Doppler shift. Here we discuss new analysis of the received state reconstruction performance in the presence of high channel loss and multiple pair events. Additionally, initial characterization of a waveguide-based entanglement source intended for space will be presented.

We examine the role of short sellers in forced turnovers. Controlling for various stock return measures, short interest predicts forced turnovers and is higher before turnovers that reveal more private information. Using Regulation SHO as a natural experiment, we show that unrestricted short selling increases the probability of forced turnovers for large firms. The effect is \emph{not} driven by a higher informativeness of stock prices. The relationship between short interest and forced turnovers is stronger in the presence of shareholder activism, while it does not vary with different board characteristics, suggesting activist shareholders are one channel for the effect.

We show that female role models increase women's willingness to compete. As in Niederle and Vesterlund (2007), we find that women are less willing to enter a tournament than men, although there are no gender differences in performance. However, the gender gap in tournament entry disappears if subjects are exposed to a competitive female role model. Results are stronger for the best performing women who seem to be particularly encouraged by female role models. Female role models also mitigate gender stereotype threats and lead to higher self-confidence among women. By contrast, we find that competitive male role models seem to intimidate female subjects and increase the gender gap in tournament entry even further. Our results have implications for the socio-political debate on how the fraction of women in top management positions can be increased.

Nowadays, high-throughput screening is essential for determining the best microbial strains and fermentation conditions. Although microtiter plates allow higher throughput in screening than shake flasks, they do not guarantee sufficient oxygen supply if operated at unsuitable conditions. This is especially the case in viscous fermentations, potentially leading to poor liquid movement and surface growth. Therefore, in this study, two aims were pursued. First, an industrial Trichoderma reesei shake flask protocol is improved with respect to oxygen supply and production. Second, this improved shake flask protocol is scaled down into microtiter plate under consideration of similar oxygen supply. For this purpose, the respiration activity monitoring system (RAMOS) was applied. An approach based on a sulfite system was introduced to ensure equal maximum oxygen transfer capacities (OTRmax) in microtiter plates and shake flasks. OTRmax-values of 250 mL shake flasks and 24-well microtiter plates were determined in a wide range of operating conditions. These sulfite datasets were used to identify operating conditions leading to the same oxygen supply for T. reesei in shake flasks and 24-well microtiter plates. For 24-well microtiter plates, the shake flask OTRmax of 20 mmol/L/h of an industrial protocol was obtained under the following optimal operating conditions: 1 mL filling volume per well, 200 rpm shaking frequency and 50 mm shaking diameter. With these conditions almost identical oxygen transfer rates and product concentrations were measured in both scales. The proposed approach is a fast and accurate means to scale-down established screening procedures into microtiter plates to achieve high-throughput.

Heterogeneities occur in various bioreactor designs including cell retention devices. Whereas in external devices changing environmental conditions cannot be prevented, cells are retained in their optimal environment in internal devices. Conventional reverse-flow diafiltration utilizes an internal membrane device, but pulsed feeding causes spatial heterogeneities. In this study, the influence of conventional reverse-flow diafiltration on the yeast Hansenula polymorpha is investigated. Alternating 180 s of feeding with 360 s of non-feeding at a dilution rate of 0.2 h−1 results in an oscillating DOT signal with an amplitude of 60%. Thereby, induced short-term oxygen limitations result in the formation of ethanol and a reduced product concentration of 25%. This effect is enforced at increased dilution rate. To overcome this cyclic problem, sequential operation of three membranes is introduced. Thus, quasi-continuous feeding is achieved reducing the oscillation of the DOT signal to an amplitude of 20% and 40% for a dilution rate of 0.2 h−1 and 0.5 h−1, respectively. Fermentation conditions characterized by complete absence of oxygen limitation and without formation of overflow metabolites could be obtained for dilution rates from 0.1 h−1 to 0.5 h−1. Thus, sequential operation of three membranes minimizes oscillations in the DOT signal providing a nearly homogenous culture over time.

The demand for biopharmaceuticals, such as monoclonal antibodies, has risen significantly over the last years. To be competitive, continuous production processes that yield consistent product quality and an economic advantage are desirable. In this study, an in situ product recovery process is described, involving use of submerged membranes to recover single-chain antibodies from a continuous fermentation of Hansenula polymorpha yeast cells. Reverse-flow diafiltration (RFD) was applied to prevent cake-layer formation. Optimal flux ranges for this process could be identified by a systematic flux step method. The RFD process was optimized, preventing mixing of permeate and unreacted substrate: the space–time yield of antibodies using RFD could be tripled. Increase of the fouling related transmembrane pressure was below 45 Pa min−1 for all applied dilution rates, indicating that the filtration process was stable. The membrane as well as the feeding mode of RFD did not influence cell viability nor product concentration. A wide range of dilution rates was successfully tested, demonstrating that this process is suitable for industrial applications. Biotechnol. Bioeng. 2014;111: 1566–1576. © 2014 Wiley Periodicals, Inc.

Single-use technologies, and thereby polymer materials, are increasingly applied in laboratory and large-scale fermentations. However, little is known about how leaching of polymer additives may affect the culture and compromise GMP regulations. The aim of this study is to introduce a standardized analytical device to test the biocompatibility of such polymer materials. The breathing behavior of various microorganisms was determined with the Respiration Activity MOnitoring Systems (RAMOS) as a function of the added amount of polymer commonly applied in biotechnology. Nylon and polyamide 12, used in cable ties and tubing, respectively, were found to delay and inhibit microbial growth. This is caused by leaching of the plasticizer N-butylbenzenesulfonamide and monomer 1,8-diazacyclotetradecane-2,7-dione, respectively, from the polymers. A metabolic activity inhibition threshold concentration between 4–10 g/L was determined for polyamide 12 tubing. In conclusion, RAMOS is a sensitive and time-effective device to qualify materials before they are applied in cultures.

Die vorliegende explorative Studie wird der Kritik an der kognitiven Ausrichtung des Konzeptes der Einwilligungsfähigkeit gerecht, indem sie erstmals mögliche emotionale Korrelate der Fähigkeit, in eine wissenschaftliche Untersuchung einzuwilligen, untersucht. Bei 21 gesunden Älteren und 20 Patienten mit leichter bis mittelschwerer Demenz wurde einerseits die Einwilligungsfähigkeit mittels einer deutschen Version des MacCAT-CR erfasst und andererseits die situationsbezogene emotionale Befindlichkeit und situative Ängstlichkeit erhoben. Die Ergebnisse deuten darauf hin, dass sich vor allem die positive Stimmung während des MacCAT-CR-Interviews auf die Einschätzung der Einwilligungsfähigkeit günstig auswirken kann. Ferner wurde ein signifikanter Einfluss der positiven Stimmung auf den Ausgang der Entscheidung für oder gegen eine Studienteilnahme aufgezeigt. Die Bedeutung dieser Ergebnisse für die Einwilligungsfähigkeitsforschung insbesondere bei Demenz-Patienten wird im Anschluss diskutiert und Vorschläge für künftige Forschungsprojekte unterbreitet.

This article investigates the impact of piped water supply and sanitation on health outcomes in urban Yemen using a combination of quasi-experimental methods and results from microbiological water tests. Variations in project roll-out allow separate identification of water and sanitation impacts. Results indicate that access to piped water supply worsens health outcomes when water rationing is frequent, which appears to be linked to a build-up of pollution in the network. When water supply is continuous no clear health benefits are found compared to traditional urban water supply through water vendors. Connections to piped sewers can lead to health improvements, conditional on regular water supply. The findings suggest that investments in piped water supply should not be made when availability and reliability of water cannot be guaranteed.

The results shown in this paper are part of a study to investigate the use of nanofiltration membranes for the recycling of phosphorus from sewage sludge. It especially contains the results of an experimental study about the influencing factors pressure, pH and feed composition on the selectivity of nanofiltration membranes for phosphoric acid and multivalent cations. For the use of pretreated sewage sludge an effective pressure of 11 bar could be identified as an effective operational point. The selectivity turned out to increase with decreasing pH which was studied in a pH-interval of pH 1–4. An increasing concentration of multivalent cations in the feed solution had a negative effect on the permeability of phosphoric acid. Accordingly it could be observed that the nanofiltration worked significantly more effective with sewage sludge ash eluates of the concentration 10 g/l than eluates of the concentration 100 g/l.

Velocity-model determination during seismic data processing is crucial for any kind of depth imaging. We compared two approaches of grid tomography: prestack stereotomography and normal-incidence-point (NIP) wave tomography. Whereas NIP wave tomography is based on wavefield attributes obtained during the common reflection surface stack and thus on the underlying hyperbolic second-order traveltime approximation, prestack stereotomography describes traveltimes by local slopes (i.e., linearly) in the prestack data domain. To analyze the impact of the different traveltime approximations and the different input-data domains on velocity model building, we applied two implementations of these techniques to two profiles of a field marine data set from the Levante Basin, eastern Mediterranean. Because ofthe presence of a thick, tabular mobile unit of the Messinian evaporites, strong vertical and lateral velocity contrasts had been expected. The velocity models revealed the reconstruction of high-velocity contrasts by grid tomographic methods is limited because of the smooth description of the velocity distribution. The lateral resolution of velocities obtained from prestack stereotomography appears to be better than those from NIP wave tomography, which is related to the difference in the approximation of traveltimes, the determination of input data, and the description of the velocity distribution. Other differences are caused mainly by different implementations of the inversion schemes. Nevertheless, both algorithms provide suitable models for high-quality depth imaging, whereas most of the reflections are fairly flat in CIGs.

This article has been removed: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy).This article has been removed at the request of the Executive Publisher.This article has been removed because it was published without the permission of the author(s).

In microtiter plates, conventional online monitoring of biomass concentration based on optical measurements is limited to transparent media: It also cannot differentiate between dead or viable biomass or suspended particles. To address this limitation, this study introduces and validates a new online monitoring setup based on impedance spectroscopy for detecting only viable biomass in 48- and 96-well microtiter plates. The setup was first validated electronically and characterized by determining the cell constants of the measuring geometry. Defined cell suspensions of Ustilago maydis, Hansenula polymorpha, Escherichia coli and Bacillus licheniformis were characterized to find, among other parameters, the most suitable frequency range and the characteristic frequency of β-dispersion for each organism. Finally, the setup was exemplarily applied to monitor the growth of Hansenula polymorpha online. As reference, three different parallel cultures were performed in established cultivation systems. This new online monitoring setup based on impedance spectroscopy is robust and enables precise measurements of microbial biomass concentration. It is promising for future high-throughput applications.

The demand for biopharmaceuticals, such as monoclonal antibodies, has risen significantly over the last years. To be competitive, continuous production processes that yield consistent product quality and an economic advantage are desirable. In this study, an in situ product recovery process is described, involving use of submerged membranes to recover single-chain antibodies from a continuous fermentation of Hansenula polymorpha yeast cells.Reverse-flow diafiltration (RFD) was applied to prevent cake layer formation. Optimal flux ranges for this process could be identified by a systematic flux step method. The RFD process was optimized, preventing mixing of permeate and unreacted substrate: the space-time yield of antibodies using RFD could be tripled. Increase of the fouling related transmembrane pressure was below 45 Pa min(-1) for all applied dilution rates, indicating that the filtration process was stable. The membrane as well as the feeding mode of RFD did not influence cell viability nor product concentration. A wide range of dilution rates was successfully tested, demonstrating that this process is suitable for industrial applications.

Heterogeneities occur in various bioreactor designs including cell retention devices. Whereas in external devices changing environmental conditions cannot be prevented, cells are retained in their optimal environment in internal devices. Conventional reverse-flow diafiltration utilizes an internal membrane device, but pulsed feeding causes temporal heterogeneities. In this study, the influence of conventional reverse-flow diafiltration on the yeast Hansenula polymorpha is investigated. Alternating 180 s of feeding with 360 s of non-feeding at a dilution rate of 0.2 h(-1) results in an oscillating DOT signal with an amplitude of 60%. Thereby, induced short-term oxygen limitations result in the formation of ethanol and a reduced product concentration of 25%. This effect is enforced at increased dilution rate. To overcome this cyclic problem, sequential operation of three membranes is introduced. Thus, quasi-continuous feeding is achieved reducing the oscillation of the DOT signal to an amplitude of 20% and 40% for a dilution rate of 0.2 h(-1) and 0.5 h(-1) , respectively. Fermentation conditions characterized by complete absence of oxygen limitation and without formation of overflow metabolites could be obtained for dilution rates from 0.1 h(-1) - 0.5 h(-1) . Thus, sequential operation of three membranes minimizes oscillations in the DOT signal providing a nearly homogenous culture over time.

Die mediale Berichterstattung zur Polizeilichen Kriminalstatistik (PKS) kulminiert nach der Veröffentlichung der kommunalen und Landesstatistiken im Frühjahr jeden Jahres mit der Veröffentlichung der bundesweiten Kriminalstatistik. Die Versuche der Sicherheitsbehörden (konkret des Bundeskriminalamts, das die Statistik auf Bundesebene bündelt), die Erwartungen und Deutungsspielräume der PKS aus methodischen Gründen einzugrenzen, laufen dabei jedoch regelmäßig bereits im Rahmen der Erstpräsentation ins Leere. Wir sehen insbesondere beim Fokus auf die bloße Kennzahl „Straftaten pro 100.000 Bewohner“ zwei zentrale Probleme, auf die im Folgenden eingegangen werden soll: Die problematische statistische Basis der PKS und ihrer Alternativen sowie der gleichwertige Eingang unterschiedlichster Kriminalitätsformen in die Kennzahl – allenthalben werden Häufigkeiten von Mord und Totschlag gesondert berücksichtigt.

It is often assumed that international labor migration from Tajikistan, while having no noticeable effects on investment (usually defined as medium and long-term consumption, such as education, or investment into housing or business), on average leads to an increase in short-term consumption, mostly food. In this paper, a simple household-level model determining the migration decision is developed and tested empirically. In a second step, the effect of low-skilled labor migration on household expenditure shares is analyzed using 2SLS. While only weak effects of migration measured by a simple dummy are visible, repeating the analysis using the length of the migration spell instead, as well as its squared term, reveals that labor migration apparently takes a while to "kick in" and become profitable to those remaining at home. The observed long-term effects on household consumption patterns, albeit being rather small, actually speak in favour of investment of remittances, with the respective shares increasing over time, while the budget share spent on food slowly decreases.

Nachdem jahrzehntelang Projekte in der Entwicklungszusammenarbeit entweder gar nicht oder bestenfalls intern nach uneinheitlichen Standards hinsichtlich ihrer Wirkung bewertet wurden, rückt nun seit einiger Zeit die methodisch fundierte, quantitative Impactevaluierung immer mehr in den Vordergrund. Auch Deutschland hat 2012 mit der Gründung des unabhängigen Deutschen Evaluierungsinstituts der Entwicklungszusammenarbeit (DEval) einen wichtigen Schritt in diese Richtung unternommen. Es leuchtet ein, dass eine objektive Erfolgsmessung von Projekten nötig ist um eine effiziente Allokation begrenzter finanzieller Mittel zu ermöglichen. Darüber hinaus ist es ebenfalls wichtig sicher zu stellen, dass eine Intervention auch tatsächlich die erwarteten positiven Effekte aufweist und nicht etwa unvorhergesehene negative Auswirkungen auf die Zielbevölkerung hat (Terberger (2011)). Die Schwierigkeiten, die es hierbei zu beachten gilt, sollen im Folgenden kurz erörtert werden.

This report aims to show the distribution of crime in Germany. For this, police crime statistics (polizeiliche Kriminalstatistik – PKS) are treated so that they integrate dark figures (unreported crime) of crime types along with their specific grade of burden. The different treatments are based on own recent survey data. Two major trends are confirmed by both treatment methods: First, there is a northsouth divide, with the northern regions experiencing a far higher risk of crime. Second, rural/urban differences can be accounted for by the higher levels of everyday crime that affect citizens of towns and cities. These slight differences and changes are more evident and meaningful in state-to-state comparisons rather than looking at Germany as a whole.

The financial crisis in 2008/2009 substantially influenced the everyday social and economic life of many Tajik people, including their behavior in the labor market. However, not much is known about the dynamics of the labor markets of the transition economies, especially in the context of the current financial crisis. Arguably, this is mainly due to paucity of panel data. In this paper, we aim to study the impact of the economic crisis on individual labor market outcomes in Tajikistan. This is the first study investigating the possible impact of the financial crisis in a transition country and uses a unique panel data set from Tajikistan. Although an impact evaluation in the true sense is impossible, due to the lack of a control group, comparing before and after-crisis outcomes can give insights as to how the crisis might have affected labor market outcomes. We do this by calculating transition probabilities between employment categories between 2007 and 2009, using a simple count method as well as predicted probabilities from multinomial probit regressions. Our results suggest an increased probability of moving into unemployment, inactivity or unpaid work during the crisis, with the self-employed being at more risk than the wage employed. This effect is more pronounced for females, as well as for very young and very old individuals. We also find that labor migration (predominantly to Russia) could be a mitigation strategy during the crisis.