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Terrestrial gravimetry allows for integrative measurements of mass changes associated with water storage variations in all storage compartments above and below the Earth surface. Superconducting gravimeters (SGs) currently are the most precise instruments for continuous monitoring of gravity change. Their footprint typically covers a radius of about 1 km around the instrument, with most of the signal originating from within the first 100 meters. We installed a SG (iGrav033) in a mixed pine-beech-oak forest in the TERENO observatory in the lowlands of north-eastern Germany. It is housed in a small field enclosure with less than 1 m2 base area, on top of a stable concrete pillar. Complementary hydro-meteorological monitoring data are available at the site, including a weather station, a groundwater monitoring well, clusters of soil moisture sensors along deep soil profiles, interception measurements and near-surface soil moisture from Cosmic Ray Neutron Sensing. For quantification and correction of the long-term instrumental SG drift, repeated measurements with an FG5 absolute gravimeter were carried out. The gravity residual time series (gravity measurements reduced to the local hydrological effect) covers a sequence of years with below average precipitation, from 2018 to 2022. We show the gravity-based water storage variations in the forested landscape throughout this period, indicating that storage depletion during summer in most years is not fully recovered by the subsequent wetter winter periods. The amplitudes of gravity-based water storage variations tend to exceed those observed by soil moisture sensors in the top meters of the soil and of groundwater. This indicates the value of terrestrial gravimetry in revealing dynamics of the deeper unsaturated zone water storage.

The vadose zone plays a key-role for a comprehensive understanding of hydrological states and processes at the interfaces of atmosphere, soil, vegetation and groundwater. Yet it is the most difficult hydrological compartment to observe water storage and fluxes due to limited accessibility and high heterogeneity. Terrestrial gravimetry represents a potentially useful monitoring method for this compartment. Its non-invasive and integrative nature provides many advantages compared to traditional hydrological field methods. Nevertheless, these benefits go along with some methodological downsides: vadose zone water storage changes, for instance, can only be disentangled from integrative measurements if all undesired signal components are known. This can be a challenge in particular for observations with a single gravimeter. However, using two gravimeters may open up new possibilities as the undesired signal components may cancel out when calculating the differences of the gravity observations of both devices. The latter approach was applied in the presented study.We carried out monthly relative gravity campaigns in the TERENO Observatory (Mueritz National Park, North-East Germany) using 2 Scintrex CG-6 gravimeters (#58, #69). On this site, we have an iGrav (#33) continuously operating since end of 2017. In May of 2019 we started with the monthly campaigns in an about 170 years old water well shaft, located at a distance of about 50 m from the iGrav. This well shaft has a diameter of roughly 2 m and a total depth of 13 m. The groundwater table is one to two meters below the well bottom and continuously monitored. During the campaigns in each month, we performed repeated gravity measurements on 3 pillars: one next to the iGrav, one next to the well shaft on the terrain surface and one on the bottom of the well shaft. This monthly data is compared and chronologically connected to the continuous recordings of the iGrav. Differences of the CG-6 gravity measurements between top and bottom of the well provide a unique dataset for describing the water storage variations in the vadose zone of 13 m thickness. Additionally, we set these observations into the context of meteorological and near-surface soil moisture time series monitored at the site.

Throughout the last years, there is an increasing interest of the geoscientific community in using terrestrial gravimetry as an integrative and non-invasive method for observing mass change and mas...

In the course of the Helmholtz MOSES initiative two monitoring systems are being developed which consist of the same key components and thus functionality but with very different scopes of application. One is a stationary data logger with a classic measurement routine (on/off duty cycle) and support for various hardware interfaces (2xSDI12, 1xRS485, 2xUART, amongst others). The other is a drifting data logger that stays idle until a flood event activates the logger and carries it downstream. On-board are turbidity, EC and temperature sensors, a GPS and an inertial measurement unit (IMU) monitoring turbulence.Advancements in electronics driven by automotive, mobile and IoT applications led to the development of very powerful, small and low power microcontrollers. This is why we decided to leave the realms of ATMega 8-bit systems (such as Arduino) and move towards ARM Cortex 32-bit systems. More precisely we used the Teensy 3.5 microcontroller development system as the core for the two systems. It is superior to Arduino in terms of performance while its developing team tries to maintain compatibility to Arduino in terms of programming vocabulary. This allows easier migration but comes also with restrictions regarding the capabilities of the hardware.The other key component is the FiPy which supports five different wireless network types (WiFi, Bluetooth, LoRa, Sigfox, LTE-M) in one module. In comparison to most other hardware it runs MicroPython which adds more complexity to the project. Even though it is a microcontroller and features also several hardware interfaces, power consumption is far from low power, which is why it is used here only for remote communication and data transmission. In addition, several design decisions were made regarding power path routing and jumper configuration to improve the systems’ overall versatility, debugging capabilities and low power functionality, which are often key to the feasibility of a remote monitoring system.

Unparalleled strength, chemical stability, ultimate surface-to-volume ratio and excellent electronic properties of graphene make it an ideal candidate as a material for membranes in micro- and nanoelectromechanical systems (MEMS and NEMS). However, the integration of graphene into MEMS or NEMS devices and suspended structures such as proof masses on graphene membranes raises several technological challenges, including collapse and rupture of the graphene. We have developed a robust route for realizing membranes made of double-layer CVD graphene and suspending large silicon proof masses on membranes with high yields. We have demonstrated the manufacture of square graphene membranes with side lengths from 7 micro meter to 110 micro meter and suspended proof masses consisting of solid silicon cubes that are from 5 micro meter multiply 5 micro meter multiply 16.4 micro meter to 100 micro meter multiply 100 micro meter multiply 16.4 micro meter in size. Our approach is compatible with wafer-scale MEMS and semiconductor manufacturing technologies, and the manufacturing yields of the graphene membranes with suspended proof masses were greater than 90%, with more than 70% of the graphene membranes having more than 90% graphene area without visible defects. The graphene membranes with suspended proof masses were extremely robust and were able to withstand indentation forces from an atomic force microscope (AFM) tip of up to ~7000 nN. The measured resonance frequencies of the realized structures ranged from tens to hundreds of kHz, with quality factors ranging from 63 to 148. The proposed approach for the reliable and large-scale manufacture of graphene membranes with suspended proof masses will enable the development and study of innovative NEMS devices with new functionalities and improved performances., 39 pages, 15 figures

Wafer bonding methods with ultra-thin intermediate bonding layers are critically important in heterogeneous 3D integration technologies for many NEMS and photonic device applications. A promising wafer bonding approach for 3D integration is adhesive bonding. So far however, adhesive bonding processes relied on relatively thick intermediate adhesive layers. In this paper, we present an adhesive wafer bonding process using an ultra-thin intermediate adhesive layer with sub-200 nm thickness. We demonstrate adhesive bonding of silicon wafers with a near perfect bonding yield of >99% and achieve less than ±10% non-uniformity of the intermediate layer thickness across an entire 100 mm-diameter wafer. A bond strength of 4.8 MPa was measured for our polymer adhesive, which is considerably higher than previously reported for other ultra-thin film adhesives. Additionally, the adhesive polymer used in the proposed method features excellent chemical and mechanical stability. We also report on a potential strategy for mitigating the formation of micro-voids in the polymer adhesive at the bond interface. Furthermore, the polymer adhesive can be sacrificially removed by oxygen plasma etching for both isotropic and anisotropic release etching. The characteristics of the adhesive wafer bonding process and its compatibility with CMOS wafers, makes it very attractive for heterogeneous 3D integration processes targeted at CMOS-integrated NEMS and photonic devices.

Nanoelectromechanical system (NEMS) sensors and actuators could be of use in the development of next generation mobile, wearable, and implantable devices. However, these NEMS devices require transducers that are ultra-small, sensitive and can be fabricated at low cost. Here, we show that suspended double-layer graphene ribbons with attached silicon proof masses can be used as combined spring-mass and piezoresistive transducers. The transducers, which are realized using processes that are compatible with large-scale semiconductor manufacturing technologies, can yield NEMS accelerometers that occupy at least two orders of magnitude smaller die area than conventional state-of-the-art silicon accelerometers., 42 pages, 4 figures

For a better understanding of the sustainability of geothermal resources, we want to quantify subsurface masschanges caused by production and injection of fluids at the Theistareykir geothermal field in Northeast Iceland.For this purpose, we installed three superconducting gravity meters (iGrav006, iGrav015 and iGrav032) and twospring gravity meters (gPhone061 and gPhone128) in vicinity to the new geothermal power plant that started op-eration in October 2017.Prior to the Iceland installation, all gravity meters were setup at the gravimetric observatory J9 in Strasbourg forsimultaneous side-by-side measurements. The obtained data were used for instrumental calibration, comparisonof noise levels and tidal analysis. In Theistareykir, three of our measuring sites are set up close to the geother-mal production and injection wells. The fourth site is located outside the geothermal field, to provide referencemeasurements that are unaffected by the activities of the power plant. At each site additional physical parameters,which influence the local gravity signal, are measured. This includes the continuous monitoring of GPS-positions,rainfall, soil moisture and snow thickness. Moreover, snow weight and snow water equivalent are measured at thesite close to the production wells.Here, we present the results of the unique intercomparison of three superconducting gravity meters and twogPhones at Strasbourg and the initial time series obtained at the geothermal site in Iceland. A preliminary in-terpretation of the gravity variations with regard to the geothermal activities and the hydro-metrological dynamicsis given.

This paper presents a novel approach for low-stress packaging of microelectromechanical system (MEMS)-based gyroscopes. The proposed approach makes use of conventional ball-stitch wire bonding. The gyroscope die is attached exclusively by means of bond wire connections between the package frame, and the top and bottom surfaces of the die. The process enables the electrical connection of metal pads on the top and the bottom side of the MEMS die within the same process. No adhesives, glue, or solder is used for the die attach. The stiffness of the proposed die attach is evaluated by scanning laser Doppler vibrometry. White-light interferometry is used to investigate stress in the die that is induced by the die attach. The bond wire attachment is compared with conventional single-sided die attach using two types of commercially available adhesives. It was found that the proposed packaging system exhibits multiple resonance modes and displays a dependence on the amount of bond wires. White-light interferometry reveals a centered bow across the die and shows low-induced stresses compared with conventionally attached dies using epoxy adhesives. [2014-0194]

This paper presents a two-stage small signal intermediate frequency amplifier for high-temperature communication systems. The proposed amplifier is implemented using in-house silicon carbide bipolar technology. Measurements show that the proposed amplifier can operate from room temperature up to 251 °C. At a center frequency of 54.6 MHz, the amplifier has a gain of 22 dB at room temperature, which decreases gradually to 16 dB at 251 °C. Throughout the measured temperature range, it achieves an input and output return loss of less than-7 and-11 dB, respectively. The amplifier has a 1-dB output compression point of about 1.4 dBm, which remains fairly constant with temperature. Each amplifier stage is biased with a collector current of 10 mA and a base-collector voltage of 3 V. Under the aforementioned biasing, the maximum power dissipation of the amplifier is 221 mW. QC 20180509

This letter presents an active down-conversion mixer for high-temperature communication receivers. The mixer is based on an in-house developed 4H-SiC BJT and down-converts a narrow-band RF input signal centered around 59 MHz to an intermediate frequency of 500 kHz. Measurements show that the mixer operates from room temperature up to 500 °C. The conversion gain is 15 dB at 25 °C, which decreases to 4.7 dB at 500 °C. The input 1-dB compression point is 1 dBm at 25 °C and −2.5 dBm at 500 °C. The mixer is biased with a collector current of 10 mA from a 20 V supply and has a maximum DC power consumption of 204 mW. High-temperature reliability evaluation of the mixer shows a conversion gain degradation of 1.4 dB after 3-hours of continuous operation at 500 °C. QC 20180601

An extensive survey of the standing genetic variation in natural populations is among the priority steps in developing a species into a model system. In recent years, green foxtail (Setaria viridis), along with its domesticated form foxtail millet (S. italica), has rapidly become a promising new model system for C4 grasses and bioenergy crops, due to its rapid life cycle, large amount of seed production and small diploid genome, among other characters. However, remarkably little is known about the genetic diversity in natural populations of this species. In this study, we survey the genetic diversity of a worldwide sample of more than 200 S. viridis accessions, using the genotyping-by-sequencing technique. Two distinct genetic groups in S. viridis and a third group resembling S. italica were identified, with considerable admixture among the three groups. We find the genetic variation of North American S. viridis correlates with both geography and climate and is representative of the total genetic diversity in this species. This pattern may reflect several introduction/dispersal events of S. viridis into North America. We also modelled demographic history and show signal of recent population decline in one subgroup. Finally, we show linkage disequilibrium decay is rapid (

This correspondence highlights an error in the above-titled paper. The corrected material is presented here.

Non-dispersive infrared (NDIR) gas spectroscopy is a highly accurate optical gas sensing technology, which has been implemented in various industrial applications. However NDIR systems remain too expensive for many consumer and automotive apphcations. The cost of the infrared (IR) emitter component is a substantial part of the total system cost. In this paper we report of a single filament IR emitter that is fabricated using wire bonding technology. Our fabrication approach offers the prospect of a fully automated assembly by means of utihzing a wire bonding tool to integrate the single filament to the MEMS structured silicon substrate. An apphcation-specific wire bond trajectory enables the mechanical attachment of the filament to form the meander-shaped emitter with a total area of 1 mm2. The fabricated IR emitter utilizes a Kanthal (FeCrAl) filament with very high thermal stability and excellent emitting properties under atmospheric conditions. The packaged IR emitter has been characterized using Fourier transform infrared (FTIR) spectroscopy to study the emitted IR spectrum with respect to the requirements of NDIR systems. QC 20171211

In this paper we report of a novel and very simple fabrication method for realizing amperometric gas sensors using conventional wire bonding technology. Working and counter electrodes are made of 360 vertically standing bond wires, entirely manufactured by a fully automated, standard wire bonding tool. Our process enables standing bond wires with a length of 1.24 mm, resulting in an extremely high aspect-ratio of 50, thus effectively increasing the surface area of the working electrode. All gas sensor electrodes are embedded in a polymer-based, solid electrolyte. Therefore, laborious handling of liquid electrolytes can be avoided. Here, we report of a nitric oxide (NO) gas sensor that is capable of detecting NO gas concentrations down to the single-digit ppm range. The proposed approach demonstrates the feasibility towards a scalable and entire back-end fabrication concept for low-cost NO gas sensors. QC 20171211

Graphene membranes act as highly sensitive transducers in nanoelectromechanical devices due to their ultimate thinness. Previously, the piezoresistive effect has been experimentally verified in graphene using uniaxial strain in graphene. Here, we report experimental and theoretical data on the uni- and biaxial piezoresistive properties of suspended graphene membranes applied to piezoresistive pressure sensors. A detailed model that utilizes a linearized Boltzman transport equation describes accurately the charge-carrier density and mobility in strained graphene and, hence, the gauge factor. The gauge factor is found to be practically independent of the doping concentration and crystallographic orientation of the graphene films. These investigations provide deeper insight into the piezoresistive behavior of graphene membranes.

The major task of a safety surveillance concept is to support the closed loop of reservoir management, i.e. to guarantee an iterative interaction between reservoir monitoring and numerical simulation. The presented research is based on the experience gained on the permanent geoelectrical monitoring at the Ketzin CO2 pilot storage site continuously operating since 2007. We have structured this experience in a modular monitoring workflow which offers well prepared links to actual process data, petrophysical data, and reservoir simulation. First results have been reached in major topics such as site-specific customization of technical tools, data acquisition and processing, and data evaluation. Structuring this approach in a modular manner allows the geoelectric monitoring at the Ketzin site to be efficiently scaled up and adapted to the fit-for-purpose requirements of future CCS demonstrations.

Die Gehalte von polychlorierten Biphenylen (PCB) und polycyclischen aromatischen Kohlenwasserstoffen (PAK) gehoren zu den am haufigsten bestimmten Parametern in der Umweltanalytik. Die detaillierte Beschreibung des Vorgehens zeigt, wie sich mit GC-MS/MS beide Stoffklassen mit Wasserstoff statt Helium als Tragergas parallel messen lassen.

Plasmopara viticola is the causal agent of grapevine downy mildew and is among the most important diseases in viticulture. It originates from North America, where it coevolved with wild Vitis species. Beginning in the 1870s it turned into a global epidemic that has been causing severe yield losses. It is generally believed that a single species is causing downy mildew on a large variety of economically important cultivars. Here we report, based on one nuclear and two mitochondrial markers, that isolates from vineyards in the United States fall into three highly distinct phylogenetic lineages. One of these contains European strains and affects Vitis vinifera cultivars, while the other two lineages affect also other species of Vitis. The divergence between these lineages is high, and, judging from the genetic variation in other Plasmopara lineages, might reflect distinct species. Due to the potentially significant implications for quarantine regulations and resistance breeding, detailed studies will be necessary to clarify whether these genetically distinct lineages occur outside of North America or are still confined there.

Heterogeneous integration of micro- and nano-electromechanical systems (MEMS, NEMS) and photonic devices on top of integrated circuits (ICs) is an emerging technology that will lead to highly compact devices combining traditional ICs with advanced sensors and actuators. Different components, such as MEMS, photonic devices, and complementary metal oxide semiconductor (CMOS) circuits are fabricated on separate substrates and subsequently joined into one single substrate by wafer bonding [1,2]. This enables the integration of high-performance MEMS, NEMS, and photonic devices made of materials such as mono-crystalline silicon, germanium, III–V materials, piezoelectric materials, shape memory alloys (SMAs), carbon nanotubes (CNT), or nanowires directly on top of ICs, which is otherwise not possible. We review heterogeneous integration approaches for various MEMS, NEMS, and photonics systems based on layer transfer by adhesive wafer bonding. The main advantages of adhesive wafer bonding are the low bonding temperatures (20 - 450°C), its insensitivity to wafer surface topology, the compatibility with standard CMOS wafers, and the ability to join practically any wafer materials [3]. Adhesive wafer bonding does not require special wafer surface treatments, such as planarization or excessive cleaning, and therefore, offers a simple and cost-effective transfer process. Layer transfer by adhesive wafer bonding consists of several steps. First, the donor wafer, containing the layer to be transferred, is aligned to the target wafer (e.g. CMOS wafer) and bonded using an intermediate polymer adhesive. Second, the bulk material (e.g. Si substrate) of the donor wafer is sacrificially etched while the transferred layer remains on the target wafer of top of the polymer layer. The transferred layer can subsequently be further processed using conventional process steps to create the desired devices. Compatible processes include structuring and etching of the transferred layer, material deposition such as chemical and physical vapour deposition (CVD, PVD), ion implantation, and annealing amongst others. These processes can be used to create electrical, mechanical, and photonic devices and electrical interconnections between the transferred layers and the underlying substrate (vias). Using adhesive bonding with an intermediate polymer further offers highly selective and controlled sacrificial release etching capabilities in O2 plasma. This provides a simple approach for realizing free-standing MEMS and NEMS structures without wet etching and critical point drying (CPD), thus increasing manufacturing yield and reducing fabrication complexity. Lastly, the presented heterogeneous integration approach is compatible with pre-structuring of the target substrates, as well as of the transfer layer. Thus, it is possible to integrate not only layers of high-performance materials, but pre-processed devices and systems. We illustrate the versatility of adhesive wafer bonding for heterogeneous integration with different application examples of MEMS and optical systems integrated onto various target substrates. Each example requires a slightly different heterogeneous integration approach. A suspended Si/SiGe quantum-well infrared microbolometer array was integrated on top of a CMOS substrate by adhesive transfer bonding of the Si/SiGe thermistor layer and subsequent patterning of the bolometer array [4]. Since the bolometer pixels needed to be suspended, Ni pillars were formed and the polymer adhesive was sacrificially removed to free-etch the bolometer pixels. The Ni pillars provide both electrical connection to the underlying CMOS circuits and mechanical support for the suspended bolometer pixels. For the integration of nano-electromechanical (NEM) switches for ultra-low power computing applications, TiW vias were used as electrical interconnects. In order to achieve short signal path lengths and thereby increase the performance and energy efficiency of the circuits, an ultra-thin adhesive bonding layer of just 200 nm was used. In optical systems that don’t require electrical interconnections, the polymer adhesive itself can be used as mechanical support. Finally, the capability for multiple layer transfer steps was demonstrated by fabricating hidden hinge micromirror arrays [5]. In this approach, a layer of mono-crystalline silicon was transferred onto the target wafer and the mirror hinges were subsequently patterned in this layer. Pillars extending from the hinge layer to the target substrate were formed, but the polymer adhesive was not removed at this stage. Instead, a second mono-crystalline silicon layer was transferred on top of the hinge layer using adhesive bonding. The mirrors are then formed in this second transferred layer. Pillars connecting the mirrors to the hinges were formed and finally both polymer adhesive layers were sacrificially removed in O2-plasma, thus, creating free-standing micromirrors. In conclusion, the flexibility to precisely control the thickness of the adhesive polymer layers and selectively remove it makes adhesive wafer bonding a highly versatile approach for heterogeneous integration of a large variety of MEMS and photonic applications. Figure 1

 Premise of the study : This work represents the fi rst molecular phylogeny of the economically important genus Vitis , an important genetic resource for breeding in grapevine, Vitis vinifera .  Methods : A molecular phylogeny of Vitis using a combined data set of three noncoding regions of the plastid DNA genome was constructed from 47 accessions covering 30 species of Vitis. The data for the trnL-F marker were combined with previously published data across the Vitaceae.  Key results : The molecular phylogeny demonstrated monophyly of the genus Vitis . Based on the combined analysis of three genes, Vitis is split into three clades that mirror the continental distribution of these accessions. The diversity is highest in the Asian clade, but the general genetic distances across taxa from different continents are relatively small.  Conclusions : The fi ndings support a relatively recent and intense gene fl ow between East Asia and North America and the possible impact of hybridization on the evolution of the genus Vitis. Taxon identity in important stock collections should be screened carefully because roughly 10% of the accessions analyzed in the present study had been misidentifi ed.

This study focuses on the base of the Eifelian stage and on the abandoned Ohlesberg quarry. The exposed section (92 m thick) is related to the Lauch and Nohn formations. Petrographic study leads to the definition of 11 microfacies which are integrated in a palaeogeographical model. It corresponds to a complex ramp setting where carbonate, mixed and siliciclastic deposits coexist. The microfacies evolution is interpreted in terms of bathymetric and lateral variations, showing a general shallowing-upward trend and transitions between carbonate-dominated and siliciclastic-dominated sedimentary domains. This interpretation is supported by trends in magnetic susceptibility data. Even if the proximity to emerged areas appears to be the major influence on magnetic susceptibility values, the influence of carbonate productivity and wave agitation is also noted. The Ohlesberg section clearly points to the local and regional complex facies architecture, and advocates to variegated depositional environments along the Mid-Eifelian High.

This paper reports a novel approach for the fabrication of infrared (IR)emitters for non-dispersive infrared gas sensing. The proposed concept enables theintegration of superior resistive heater materials with microelectromechanical systems(MEMS) structures. In this study, non-bondable filaments made of nickel chromium areattached to mechanical attachment structures using a fully automated state-of-the-artwire bonder. The formation of the electrical contacts between the integrated filamentsand the electrical contact pattern on the substrate is performed using conventionalgold stud bumping technology. The placement accuracy of the integrated filamentsis evaluated using white-light interferometry, while the contact formation using studbumping to embed the filaments is investigated using focus ion beam milled crosssections.A proof-of-concept IR emitter has been successfully operated and heated upto 960 C in continuous mode for 3 hours. QC 20161121

Antje Kolde: Politique et religion chez Isyllos d’Épidaure. Basel: Schwabe 2003. XVI, 443 S. 1 Taf. (Schweizerische Beiträge zur Altertumswissenschaft. 28.) 75,50 €.

The identification of phosphorylation sites is essential for a full understanding of the cellular functions of proteins. However, mass spectrometric analysis is often hampered by the low abundance of phosphoproteins, the difficulty of obtaining full sequence coverage by specific proteolysis reactions, and the low ionization efficiency of phosphopeptides compared with their non-phosphorylated analogs. In the present work a beta-elimination/Michael addition was used to replace the phosphate groups of pSer or pThr by a group which gives rise to an enhanced ionization efficiency. In order to find optimum reaction conditions, beta-elimination/Michael addition was examined using phosphorylated model peptides. Whereas complete elimination of phosphate could be achieved by treatment with barium hydroxide in organic solvents such as ethanol or acetonitrile, the yield of the Michael adduct strongly depended on the nucleophile and the peptide sequence. Reaction with 2-phenylethanethiol, p-bromophenethylamine and ethylenediamine clearly resulted in products showing higher matrix-assisted laser desorption/ionization (MALDI) signal intensities compared with those of the corresponding phosphorylated precursors. The method was successfully used to identify phosphorylated sequences of ovalbumin and human Stat1 by in-gel derivatization with 2-phenylethanethiol and subsequent peptide mass fingerprint analysis of the trypsin digests. Copyright © 2004 John Wiley & Sons, Ltd.

Bei Bedarfsgegenstanden – dazu zahlen Textilien und auch Kuscheltiere – muss sichergestellt sein, dass diese nicht mit polyaromatischen Kohlenwasserstoffen (PAK) belastet sind. Hochsiedende PAK aus Textilproben lassen sich gaschromatographisch sauber trennen und dann sicher quantifizieren. Mit einem Triplequadrupol-GC-MS/MS-System sinkt die Nachweisgrenze.

Interaction with mobile consumer devices leads to a higher acceptance and affinity of persons to natural user interfaces and perceptional interaction possibilities. New interaction modalities become accessible and are capable to improve human machine interaction even in complex and high risk environments, like the operation room. Here, manifold medical disciplines cause a great variety of procedures and thus staff and equipment. One universal challenge is to meet the sterility requirements, for which common contact-afflicted remote interfaces always pose a potential risk causing a hazard for the process. The proposed operating table control system overcomes this process risk and thus improves the system usability significantly. The 3D sensor system, the Microsoft Kinect, captures the motion of the user, allowing a touchless manipulation of an operating table. Three gestures enable the user to select, activate and manipulate all segments of the motorised system in a safe and intuitive way. The gesture dynamics are synchronised with the table movement. In a usability study, 15 participants evaluated the system with a system usability score by Broke of 79. This states a high potential for implementation and acceptance in interventional environments. In the near future, even processes with higher risks could be controlled with the proposed interface, while interfaces become safer and more direct.

We demonstrate humidity sensing using a change of electrical resistance of a single- layer chemical vapor deposited (CVD) graphene that is placed on top of a SiO2 layer on a Si wafer. To investigate the selectivity of the sensor towards the most common constituents in air, its signal response was characterized individually for water vapor (H2O), nitrogen (N2), oxygen (O2), and argon (Ar). In order to assess the humidity sensing effect for a range from 1% relative humidity (RH) to 96% RH, devices were characterized both in a vacuum chamber and in a humidity chamber at atmospheric pressure. The measured response and recovery times of the graphene humidity sensors are on the order of several hundred milliseconds. Density functional theory simulations are employed to further investigate the sensitivity of the graphene devices towards water vapor. Results from the interaction between the electrostatic dipole moment of the water and the impurity bands in the SiO2 substrate, which in turn leads to electrostatic doping of the graphene layer. The proposed graphene sensor provides rapid response direct electrical read out and is compatible with back end of the line (BEOL) integration on top of CMOS-based integrated circuits., Nanoscale, 2015