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A modified Chromium 10x droplet-based protocol that subsamples cells for both short-read and long-read (nanopore) sequencing together with a new computational pipeline (FLAMES) is developed to enable isoform discovery, splicing analysis, and mutation detection in single cells. We identify thousands of unannotated isoforms and find conserved functional modules that are enriched for alternative transcript usage in different cell types and species, including ribosome biogenesis and mRNA splicing. Analysis at the transcript level allows data integration with scATAC-seq on individual promoters, improved correlation with protein expression data, and linked mutations known to confer drug resistance to transcriptome heterogeneity.

The fabrication of individual nanowire-based devices and their comprehensive electrical characterization remains a major challenge. Here, we present a symmetric Hall bar configuration for highly p-type germanium nanowires (GeNWs), fabricated by a top-down approach using electron beam lithography and inductively coupled plasma reactive ion etching. The configuration allows two equivalent measurement sets to check the homogeneity of GeNWs in terms of resistivity and the Hall coefficient. The highest Hall mobility and carrier concentration of GeNWs at 5 K were in the order of 100 cm^2/(Vs) and 4×10^19 cm^-3, respectively. With a decreasing nanowire width, the resistivity increases and the carrier concentration decreases, which is attributed to carrier scattering in the region near the surface. By comparing the measured data with simulations, one can conclude the existence of a depletion region, which decreases the effective cross-section of GeNWs. Moreover, the resistivity of thin GeNWs is strongly influenced by the cross-sectional shape.

The uploaded data are related to electrical measurements including two- and four-probe, Hall effect, and temperature-dependent measurements. The simulation data is included as well.

Background: Among asymptomatic patients with severe carotid artery stenosis but no recent stroke or transient cerebral ischaemia, either carotid artery stenting (CAS) or carotid endarterectomy (CEA) can restore patency and reduce long-term stroke risks. However, from recent national registry data, each option causes about 1% procedural risk of disabling stroke or death. Comparison of their long-term protective effects requires large-scale randomised evidence. Methods: ACST-2 is an international multicentre randomised trial of CAS versus CEA among asymptomatic patients with severe stenosis thought to require intervention, interpreted with all other relevant trials. Patients were eligible if they had severe unilateral or bilateral carotid artery stenosis and both doctor and patient agreed that a carotid procedure should be undertaken, but they were substantially uncertain which one to choose. Patients were randomly allocated to CAS or CEA and followed up at 1 month and then annually, for a mean 5 years. Procedural events were those within 30 days of the intervention. Intention-to-treat analyses are provided. Analyses including procedural hazards use tabular methods. Analyses and meta-analyses of non-procedural strokes use Kaplan-Meier and log-rank methods. The trial is registered with the ISRCTN registry, ISRCTN21144362. Findings: Between Jan 15, 2008, and Dec 31, 2020, 3625 patients in 130 centres were randomly allocated, 1811 to CAS and 1814 to CEA, with good compliance, good medical therapy and a mean 5 years of follow-up. Overall, 1% had disabling stroke or death procedurally (15 allocated to CAS and 18 to CEA) and 2% had non-disabling procedural stroke (48 allocated to CAS and 29 to CEA). Kaplan-Meier estimates of 5-year non-procedural stroke were 2·5% in each group for fatal or disabling stroke, and 5·3% with CAS versus 4·5% with CEA for any stroke (rate ratio [RR] 1·16, 95% CI 0·86–1·57; p=0·33). Combining RRs for any non-procedural stroke in all CAS versus CEA

A pilot study was initiated in 2018 under the Global Atmospheric Passive Sampling (GAPS) Network named GAPS-Megacities. This study included 20 megacities/major cities across the globe with the goal of better understanding and comparing ambient air levels of persistent organic pollutants and other chemicals of emerging concern, to which humans residing in large cities are exposed. The first results from the initial period of sampling are reported for 19 cities for several classes of flame retardants (FRs) including organophosphate esters (OPEs), polybrominated diphenyl ethers (PBDEs), and halogenated flame retardants (HFRs) including new flame retardants (NFRs), tetrabromobisphenol A (TBBPA) and hexabromocyclododecane (HBCDD). The two cities, New York (USA) and London (UK) stood out with ∼3.5 to 30 times higher total FR concentrations as compared to other major cities, with total concentrations of OPEs of 15,100 and 14,100 pg/m, respectively. Atmospheric concentrations of OPEs significantly dominated the FR profile at all sites, with total concentrations in air that were 2–5 orders of magnitude higher compared to other targeted chemical classes. A moderately strong and significant correlation (r = 0.625, p < 0.001) was observed for Gross Domestic Product index of the cities with total OPEs levels. Although large differences in FR levels were observed between some cities, when averaged across the five United Nations regions, the FR classes were more evenly distributed and varied by less than a factor of five. Results for Toronto, which is a ‘reference city’ for this study, agreed well with a more in-depth investigation of the level of FRs over different seasons and across eight sites representing different urban source sectors (e.g. traffic, industrial, residential and background). Future sampling periods under this project will investigate trace metals and other contaminant classes, linkages to toxicology, non-targeted analysis, and eventually temporal trends. The st

From the perspective of wafer-level integration technologies, this work presents theoretical and experimental insights on fundamental device properties of single-walled carbon nanotubes (SWCNTs) based giant piezoresistive transducers. The role of contacts in such devices and their contribution to a significant tunneling-related sensitivity enhancement is demonstrated. The origin of this phenomenon is the strain dependence of the effective Schottky barrier (SB) width which is modulated by a drain-source voltage (VDS) dependent large built-in electric field F at the Schottky-barrier (SB), which defines the effective SB width and can be controlled via VDS. Moreover, perspectives for forthcoming sensor generations exposing operation regimes beyond intrinsic sensitivity are revealed.

Random alloys are relevant for many applications. One example is silicon-germanium which is used for high frequency devices like heterojunction-bipolar transistors. We therefore investigate the electronic structure of Si1−xGex alloys in the entire composition range 0≤ x≤ 1. For our study we use density functional theory in combination with bulk models of the alloys. To describe the band gap precisely we use the pseudopotential projector shift method as implemented in QuantumATK 18.06. We perform a random generation of Si1−xGex structures to get statistical distributions of the electronic properties. After optimizing the structure we evaluate the band structure by averaging equivalent directions in the Brillouin zone. The mean of the band gap is in good agreement with experimental reference data. We also demonstrate wide variations of the band gap, which are in the range of about 10 %. Further properties, such as the lattice constant and the formation energy are studied as well. Finally, we investigated also the impact of additional carbon dopants in the silicon-germanium alloy.

Metal-semiconductor interfaces are of huge importance for applications and can be found in various field-effect transistors. We study the interface between NiSi2 and silicon on the basis of density functional theory and the NEGF formalism. Different crystal orientations and strain states are investigated systematically. We focus on the tunneling phenomena of carriers through the Schottky contact at the interface, which are crucial for the on-current in transistors. The on-current is found to be strongly dependent on strain and orientation. It will be shown that the height of the Schottky barrier determines the tunneling current. However, not all changes in the current can be traced back to the barrier height. The modification of the electronic structure matter as well, which can be modeled based on the effective mass of the tunneling carriers. We have also extracted work functions of the isolated materials which we relate to the extracted Schottky barrier heights. It will be shown that the Schottky-Mott model fails for this material system. Better approaches will be discussed in our contribution.

From the perspective of wafer-level integration technologies, this work presents theoretical and experimental insights on fundamental device properties of single-walled carbon nanotubes (SWCNTs) based giant piezoresistive transducers. The role of contacts in such devices and their contribution to a significant tunneling-related sensitivity enhancement is demonstrated. The origin of this phenomenon is the strain dependence of the effective Schottky barrier (SB) width which is modulated by a drain-source voltage (VDS) dependent large built-in electric field F at the Schottky-barrier (SB), which defines the effective SB width and can be controlled via VDS. Moreover, perspectives for forthcoming sensor generations exposing operation regimes beyond intrinsic sensitivity are revealed.

This article features the evolution of carbon nanotubes as functional material in nano and microelectromechanical systems. Introducing materials morphologies for the CNTs in a homologue series (single CNTs - bundles, fibers, yarns - networks and thin films), different concepts for mechanical sensors based on the intrinsic and extrinsic properties of the CNT material are introduced (piezoresistive effect, strain-induced band bending, charge tunneling). In a rigorous theoretical treatment, the limits of the achievable sensor performance (i.e., gauge factor) are derived and discussed in the context of applications. A careful literature survey shows that highest sensitivity is reached for devices exploiting the intrinsic transport properties of single CNTs. For reliability tests of such sensor systems made from nanomaterials and classical MEMS, a specimen-centered approach is introduced to give viable insights into the structure-property relationships and failure modes.

We present results of our investigations on nickel (Ni) silicidation of top-down fabricated silicon nanowires (SiNWs). Control over the silicidation process is important for the applications of SiNWs in reconfigurable field effect transistors (RFETs). Silicidation is performed using a rapid thermal annealing (RTA) process on the SiNWs fabricated by electron beam lithography (EBL) and inductively coupled plasma (ICP) etching. The effect of variations in crystallographic orientations of SiNWs and different NW designs on the silicidation process is studied. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) are done to study Ni diffusion, silicide phases and silicide-silicon interface. Control over the silicide phase is achieved together with atomically sharp interfaces between the silicide and silicon. We find that {111} interfaces are predominantly formed, which are energetically most favorable according to density functional theory calculations. However, control over the silicide length remains a challenge.

A model is presented which describes reconfigurable field-effect transistors (RFETs) with metal contacts, whose switching is controlled by manipulating the Schottky barriers at the contacts. The proposed modeling approach is able to bridge the gap between quantum effects on the atomic scale and the transistor switching. We apply the model to transistors with a silicon channel and NiSi2 contacts. All relevant crystal orientations are compared, focusing on the differences between electron and hole current, which can be as large as four orders of magnitude. Best symmetry is found for the < 110 > orientation, which makes this orientation most advantageous for RFETs. The observed differences are analyzed in terms of the Schottky barrier height at the interface. Our study indicates that the precise orientation of the interface relative to a given transport direction, perpendicular or tilted, is an important technology parameter, which has been underestimated during the previous development of RFETs. Most of the conclusions regarding the studied metal-semiconductor interface are also valid for other device architectures.

Carbon nanotubes (CNTs) are a one-dimensional material system with intriguing physical properties that lead to emerging applications:One example is their optical-absorption spectrum, that is highly strain dependent, while, at the same time, CNTs are unusually strain-resistant compared to bulk materials.It is a largely open question, as to what extent this effect is attributed to the physics of strain-dependent (i) electronic single-particle transitions, (ii) dielectric screening, or (iii) atomic geometries including CNT radii.To explain the influence of strain on the screened Coulomb interaction in one-dimensional systems, we report on cutting-edge first-principles theoretical spectroscopy of the strain-dependent electronic structure and optical properties of an (8,0) CNT.Quasiparticle effects are taken into account using Hedin's $GW$ approximation and excitonic effects are described by solving a Bethe-Salpeter-equation for the optical-polarization function.This provides an accurate description of the electron-electron interaction and the influence of strain on dielectric screening as well as electronic structure and optical absorption.We interpret our thoroughly converged first-principles data in terms of an existing scaling relation and facilitate wide-spread use of this relation: We show that it captures strain-dependent optical absorption with satisfactory accuracy, as long as screening, the quasiparticle band gap, and effective electron and hole masses of the strained system are known.

Carbon nanotubes (CNTs) are a one-dimensional material system with intriguing physical properties that lead to emerging applications:One example is their optical-absorption spectrum, that is highly strain dependent, while, at the same time, CNTs are unusually strain-resistant compared to bulk materials.It is a largely open question, as to what extent this effect is attributed to the physics of strain-dependent (i) electronic single-particle transitions, (ii) dielectric screening, or (iii) atomic geometries including CNT radii.To explain the influence of strain on the screened Coulomb interaction in one-dimensional systems, we report on cutting-edge first-principles theoretical spectroscopy of the strain-dependent electronic structure and optical properties of an (8,0) CNT.Quasiparticle effects are taken into account using Hedin's $GW$ approximation and excitonic effects are described by solving a Bethe-Salpeter-equation for the optical-polarization function.This provides an accurate description of the electron-electron interaction and the influence of strain on dielectric screening as well as electronic structure and optical absorption.We interpret our thoroughly converged first-principles data in terms of an existing scaling relation and facilitate wide-spread use of this relation: We show that it captures strain-dependent optical absorption with satisfactory accuracy, as long as screening, the quasiparticle band gap, and effective electron and hole masses of the strained system are known.

The electronic structure of silicon nanowires is studied using density functional theory. A radially resolved density of states is discussed for different nanowire diameters and crystal orientations, which allows new insight into the transport properties. Strong differences between the surface and the center of the nanowire are found, indicating that the carrier transport will mainly take place in the nanowire center. For increasing diameter the density of states in the center approaches the bulk value. We find that bulk properties such as the indirect nature of the band gap become already significant at a nanowire diameter of approximately 5 nm and beyond. Finally, the spatial characteristic of the current is visualized in terms of transmission pathways. The electron transport is found to be more localized in the nanowire center compared to the hole transport. It also depends on the crystal orientation of the wire.

Random alloys are relevant for many applications. One example is silicon-germanium which is used for high frequency devices like heterojunction-bipolar transistors. We therefore investigate the electronic structure of Si1−xGex alloys in the entire composition range 0≤ x≤ 1. For our study we use density functional theory in combination with bulk models of the alloys. To describe the band gap precisely we use the pseudopotential projector shift method as implemented in QuantumATK 18.06. We perform a random generation of Si1−xGex structures to get statistical distributions of the electronic properties. After optimizing the structure we evaluate the band structure by averaging equivalent directions in the Brillouin zone. The mean of the band gap is in good agreement with experimental reference data. We also demonstrate wide variations of the band gap, which are in the range of about 10 %. Further properties, such as the lattice constant and the formation energy are studied as well. Finally, we investigated also the impact of additional carbon dopants in the silicon-germanium alloy.

Metal-semiconductor interfaces are of huge importance for applications and can be found in various field-effect transistors. We study the interface between NiSi2 and silicon on the basis of density functional theory and the NEGF formalism. Different crystal orientations and strain states are investigated systematically. We focus on the tunneling phenomena of carriers through the Schottky contact at the interface, which are crucial for the on-current in transistors. The on-current is found to be strongly dependent on strain and orientation. It will be shown that the height of the Schottky barrier determines the tunneling current. However, not all changes in the current can be traced back to the barrier height. The modification of the electronic structure matter as well, which can be modeled based on the effective mass of the tunneling carriers. We have also extracted work functions of the isolated materials which we relate to the extracted Schottky barrier heights. It will be shown that the Schottky-Mott model fails for this material system. Better approaches will be discussed in our contribution.

Metal-semiconductor interfaces are of huge importance for applications and can be found in various field-effect transistors. We study the interface between NiSi2 and silicon on the basis of density functional theory and the NEGF formalism. Different crystal orientations and strain states are investigated systematically. We focus on the tunneling phenomena of carriers through the Schottky contact at the interface, which are crucial for the on-current in transistors. The on-current is found to be strongly dependent on strain and orientation. It will be shown that the height of the Schottky barrier determines the tunneling current. However, not all changes in the current can be traced back to the barrier height. The modification of the electronic structure matter as well, which can be modeled based on the effective mass of the tunneling carriers. We have also extracted work functions of the isolated materials which we relate to the extracted Schottky barrier heights. It will be shown that the Schottky-Mott model fails for this material system. Better approaches will be discussed in our contribution.

Metal-semiconductor interfaces are of huge importance for applications and can be found in various field-effect transistors. We study the interface between NiSi2 and silicon on the basis of density functional theory and the NEGF formalism. Different crystal orientations and strain states are investigated systematically. We focus on the tunneling phenomena of carriers through the Schottky contact at the interface, which are crucial for the on-current in transistors. The on-current is found to be strongly dependent on strain and orientation. It will be shown that the height of the Schottky barrier determines the tunneling current. However, not all changes in the current can be traced back to the barrier height. The modification of the electronic structure matter as well, which can be modeled based on the effective mass of the tunneling carriers. We have also extracted work functions of the isolated materials which we relate to the extracted Schottky barrier heights. It will be shown that the Schottky-Mott model fails for this material system. Better approaches will be discussed in our contribution.

Feasible device architectures for ultra-scaled CNTFETs are studied down to 5.9 nm using a multiscale simulation approach covering electronic quantum transport simulations and TCAD numerical device simulations. Schottky-like and ohmic-like contacts are considered. The simplified approach employed in the numerical device simulator is critically evaluated and verified by means of comparing the results with electronic quantum simulation results of an identical device. Different performance indicators such as the switching speed, switching energy, the subthreshold slope, Ion/Ioff-ratio, among others, are extracted for different device architectures. These values guide the evaluation of the technology for different application scenarios. For high-performance logic applications, the buried gate CNTFET is claimed to be the most suitable structure.

Feasible device architectures for ultra-scaled CNTFETs are studied down to 5.9 nm using a multiscale simulation approach covering electronic quantum transport simulations and TCAD numerical device simulations. Schottky-like and ohmic-like contacts are considered. The simplified approach employed in the numerical device simulator is critically evaluated and verified by means of comparing the results with electronic quantum simulation results of an identical device. Different performance indicators such as the switching speed, switching energy, the subthreshold slope, Ion/Ioff-ratio, among others, are extracted for different device architectures. These values guide the evaluation of the technology for different application scenarios. For high-performance logic applications, the buried gate CNTFET is claimed to be the most suitable structure.

We theoretically investigate the influence of defect-induced long-range deformations in carbon nanotubes on their electronic transport properties. To this end we perform numerical ab-initio calculations using a density-functional-based tight-binding (DFTB) model for various tubes with vacancies. The geometry optimization leads to a change of the atomic positions. There is a strong reconstruction of the atoms near the defect (called "distortion") and there is an additional long-range deformation. The impact of both structural features on the conductance is systematically investigated. We compare short and long CNTs of different kinds with and without long-range deformation. We find for the very thin (9,0)-CNT that the long-range deformation additionally affects the transmission spectrum and the conductance compared to the short-range lattice distortion. The conductance of the larger (11,0)- or the (14,0)-CNT is overall less affected implying that the influence of the long-range deformation decreases with increasing tube diameter. Furthermore, the effect can be either positive or negative depending on the CNT type and the defect type. Our results indicate that the long-range deformation must be included in order to reliably describe the electronic structure of defective, small-diameter armchair tubes.

Presentation of TP1 / DFG research unit 1713 “Sensoric micro- and nano systems

Durch die Öffnung der Grenzen, die hohe Mobilität, aber auch die starken Flüchtlingsströme gehört der Umgang mit Patienten und Patientinnen aus anderen Kulturkreisen zum ärztlichen Alltag, ganz besonders im Rhein-Main-Gebiet. Die sprachlichen und kulturellen Barrieren lösen in der medizinischen Praxis vielfach Konflikte aus, die sich auf die medizinische Behandlung als solche, aber auch auf die ethischen und religiösen Zusammenhänge auswirken. Der Ärztetag am Dom hat deshalb Fachleute kulturell verschiedener Herkunft eingeladen, Fallbeispiele vom Lebensanfang bis zum Lebensende zu erläutern.Kultursensible Medizin am Lebensanfang (Dr. med. Yasar Bilgin, Vorsitzender der Türkisch-Deutschen Gesundheitsstiftung e.V., Gießen)Das Leben im Krankenhaus und in der ärztlichen Praxis ist ein Spiegelbild des "normalen" Lebens in unserer Gesellschaft. Somit haben die öffentlichen Diskussionen um Integration und Migration auch einen Einfluss auf das Verhältnis von Arzt und Patienten und können gegebenenfalls vorhandene Vorurteile widerspiegeln. Migration ist keine Krankheit und als Mediziner behandeln wir nicht nur die biologischen Vorgänge des menschlichen Körpers, sondern den ganzen Menschen unter Beachtung seiner Lebensumstände. Denn auch die individuellen Formen der Lebensgestaltung, Sichtweisen und Vorstellungen und natürlich der Glaube haben entscheidenden Einfluss auf den Umgang mit der eigenen Gesundheit und wie man sich der Herausforderung, die eine Krankheit bedeutet, stellt. Der Beitrag "Kultursensible Medizin am Lebensanfang" widmet sich besonders den türkeistämmigen Migranten und erläutert die Besonderheiten sowie die kulturspezifischen Hintergründe dieses Patientenkollektivs. Mittlerweile lebt die vierte Generation der Zuwanderer in Deutschland, und damit sind vom Säugling bis zum Rentner alle Altersgruppen vertreten. Da in dieser Bevölkerungsgruppe eine überdurchschnittlich hohe Geburtenrate besteht, treffen wir im medizinischen Alltag auf viele Säuglinge und Kinde

Durch die Öffnung der Grenzen, die hohe Mobilität, aber auch die starken Flüchtlingsströme gehört der Umgang mit Patienten und Patientinnen aus anderen Kulturkreisen zum ärztlichen Alltag, ganz besonders im Rhein-Main-Gebiet. Die sprachlichen und kulturellen Barrieren lösen in der medizinischen Praxis vielfach Konflikte aus, die sich auf die medizinische Behandlung als solche, aber auch auf die ethischen und religiösen Zusammenhänge auswirken. Der Ärztetag am Dom hat deshalb Fachleute kulturell verschiedener Herkunft eingeladen, Fallbeispiele vom Lebensanfang bis zum Lebensende zu erläutern.Kultursensible Medizin am Lebensanfang (Dr. med. Yasar Bilgin, Vorsitzender der Türkisch-Deutschen Gesundheitsstiftung e.V., Gießen)Das Leben im Krankenhaus und in der ärztlichen Praxis ist ein Spiegelbild des "normalen" Lebens in unserer Gesellschaft. Somit haben die öffentlichen Diskussionen um Integration und Migration auch einen Einfluss auf das Verhältnis von Arzt und Patienten und können gegebenenfalls vorhandene Vorurteile widerspiegeln. Migration ist keine Krankheit und als Mediziner behandeln wir nicht nur die biologischen Vorgänge des menschlichen Körpers, sondern den ganzen Menschen unter Beachtung seiner Lebensumstände. Denn auch die individuellen Formen der Lebensgestaltung, Sichtweisen und Vorstellungen und natürlich der Glaube haben entscheidenden Einfluss auf den Umgang mit der eigenen Gesundheit und wie man sich der Herausforderung, die eine Krankheit bedeutet, stellt. Der Beitrag "Kultursensible Medizin am Lebensanfang" widmet sich besonders den türkeistämmigen Migranten und erläutert die Besonderheiten sowie die kulturspezifischen Hintergründe dieses Patientenkollektivs. Mittlerweile lebt die vierte Generation der Zuwanderer in Deutschland, und damit sind vom Säugling bis zum Rentner alle Altersgruppen vertreten. Da in dieser Bevölkerungsgruppe eine überdurchschnittlich hohe Geburtenrate besteht, treffen wir im medizinischen Alltag auf viele Säuglinge und Kinde

Reconfigurable transistors (RFETs) can be switched between electron and hole current by changing the polarity of the gate potential. This allows a much higher functionality and hence, logic operations can be realized with fewer transistors. The device performance of such a transistor is strongly dominated by the contact physics. In this work, the electron transport across the NiSi 2 -Si interface is studied using the NEGF formalism and density functional theory, which allows us to consider the atomic structure of the interface. A new model is then presented which relates the electron transport through the interface to the transfer characteristic of an RFET. The model is compared to experimental data, which shows very good agreement, especially with respect to the ratio between electron and hole current (left figure). Based on the model, different structure variations at the interface and their consequences on the device performance are discussed. It is demonstrated that best symmetry between electron and hole current is achieved for the <110> crystal orientation, which is much worse for <100> orientation (right figure). This makes the <110> orientation advantageous for RFETs. Also the influence of strain generated parallel to the interface plane is investigated (right figure). It is shown that strain can be used to tune the symmetry in case of <110> crystal orientation even further. This is entirely different for the <100> crystal orientation, where the highest electron currents are observed for all strain states. In this state, the electron currents are about three orders of magnitude higher than the hole currents. A detailed discussion of these differences based on work function and band structure analysis will be given in our contribution.

Scaling down of CMOS faces strong challenges due to which new materials, enhanced functionality and new device concepts have gained importance. These concepts include undoped silicon nanowire based reconfigurable devices which can be programmed as p-FET or n-FET by controlling the electrostatic potential applied across gate. In this work, electrical characterization of undoped sub-20 silicon nanowires (SiNWs) is reported. SiNWs are fabricated on intrinsic SOI substrates in <110> and <100> crystal directions by a top down approach. Hydrogen silsesquioxane (HSQ), a negative tone electron beam resist is used for nano- patterning as well as hard mask for etching. Nanowire etching process is optimized using an inductively coupled plasma (ICP) source and C4F8/SF6/O2 mixed gas recipe at 18 oC. These NWs are oxidized to form a SiO2 shell and subsequently silicidized. For silicidation the SiO2 shell is wet etched at pre-defined positions followed by Nickel(Ni) sputtering and diffusion which yield silicide-silicon(Schottky) junctions. Ni is used for silicidation to selectively control the charge carriers injection at the junctions. Different transport and silicidation progress was observed in <110> and <100> crystal directions.

Fully Depleted Silicon on Insulator transistors (FDSOI) are a promising approach for further scaling. The device features a fully depleted body which is isolated by an insulator box. This introduces better electrostatics, lower leakage current and thus better channel control. The device performance is heavily influenced by the orientation, confinement and strain in the ultra-thin body. In this work the electronic structure of ultra-thin silicon layers is investigated using Density Functional Theory (DFT). The simulation parameters for the model system were calibrated to reproduce the experimental band gap of bulk silicon. This ensures that the model describes the electronic structure of ultra-thin silicon layers accurately. Our study demonstrates the impact of confinement, orientation and strain on material dependent transport properties and their influence on the device performance. For this purpose our results will be used as an input for device simulations using Synopsys Sentaurus TCAD. We find that the band gap of the silicon layer increases with decreasing slab thickness which is a clear indication of quantum confinement. From the simulation, the band gap for the {100} confinement is found to be higher than {110} and {111} scenarios. Band gap is one of the factors which influence the intrinsic carrier in the semiconductor and thereby the transport. Another important factor for the transport is lattice strain. Strain is a useful method for modulating band structures. One good example is the transformation of direct band gap in {100} confined silicon slab to indirect band gap with 2 % biaxial compression. In our presentation we will discuss the influence of the effective mass as well. Furthermore, the strain dependence of the electronic structure and its impact on device properties is analyzed systematically.

The electron transport across metal-semiconductor interfaces is crucial for the functionality of reconfigurable field-effect transistors, which can be switched between electron and hole current. Devices were already fabricated experimentally, however, a profound understanding of the underlaying mechanism is not yet available. This study focuses on the NiSi2-Si interface, which is studied using the NEGF formalism. Based on the calculated transmission spectra, the transfer characteristic of a reconfigurable transistor is obtained using a simplified approach. Even though this model strongly simplifies the electrostatic environment in a transistor, very good agreement with experimental devices is demonstrated. The impact of strain on the device characteristic is studied as well. It is shown that the magnitude of electron and hole current can be altered successfully. They can also be tuned to be symmetric, which fits to experimental observations. Finally, new insight into the device functionality is gained based on our calculations of the work functions and effective masses of the isolated NiSi 2 and Si.

The nickel-carbon system has received increased attention over the past years due to the relevance of nickel as a catalyst for carbon nanotube and graphene growth, where Nickel carbide intermediates may be involved or carbide interface layers form in the end. Nickel-carbon composite thin films comprising Ni3C are especially interesting in mechanical sensing applications. Due to the meta-stability of nickel carbides, formation conditions and the coupling between mechanical and electrical properties are not yet well understood. Using first-principles electronic structure methods, we calculated the elastic properties of Ni3C, Ni2C and NiC, as well as changes in electronic properties under mechanical strain. We observe that the electronic density of states around the Fermi level does not change under the considered strains of up to 1%, which correspond to stresses up to 3GPa. Relative changes in conductivity of Ni3C range up to maximum values of about 10%.

The nickel-carbon system has received increased attention over the past years due to the relevance of nickel as a catalyst for carbon nanotube and graphene growth, where Nickel carbide intermediates may be involved or carbide interface layers form in the end. Nickel-carbon composite thin films comprising Ni3C are especially interesting in mechanical sensing applications. Due to the meta-stability of nickel carbides, formation conditions and the coupling between mechanical and electrical properties are not yet well understood. Using first-principles electronic structure methods, we calculated the elastic properties of Ni3C, Ni2C and NiC, as well as changes in electronic properties under mechanical strain. We observe that the electronic density of states around the Fermi level does not change under the considered strains of up to 1%, which correspond to stresses up to 3GPa. Relative changes in conductivity of Ni3C range up to maximum values of about 10%.

Fully Depleted Silicon on Insulator transistors (FDSOI) are a promising approach for further scaling. The device features a fully depleted body which is isolated by an insulator box. This introduces better electrostatics, lower leakage current and thus better channel control. The device performance is heavily influenced by the orientation, confinement and strain in the ultra-thin body. In this work the electronic structure of ultra-thin silicon layers is investigated using Density Functional Theory (DFT). The simulation parameters for the model system were calibrated to reproduce the experimental band gap of bulk silicon. This ensures that the model describes the electronic structure of ultra-thin silicon layers accurately. Our study demonstrates the impact of confinement, orientation and strain on material dependent transport properties and their influence on the device performance. For this purpose our results will be used as an input for device simulations using Synopsys Sentaurus TCAD. We find that the band gap of the silicon layer increases with decreasing slab thickness which is a clear indication of quantum confinement. From the simulation, the band gap for the {100} confinement is found to be higher than {110} and {111} scenarios. Band gap is one of the factors which influence the intrinsic carrier in the semiconductor and thereby the transport. Another important factor for the transport is lattice strain. Strain is a useful method for modulating band structures. One good example is the transformation of direct band gap in {100} confined silicon slab to indirect band gap with 2 % biaxial compression. In our presentation we will discuss the influence of the effective mass as well. Furthermore, the strain dependence of the electronic structure and its impact on device properties is analyzed systematically.

The electron transport across metal-semiconductor interfaces is crucial for the functionality of reconfigurable field-effect transistors, which can be switched between electron and hole current. Devices were already fabricated experimentally, however, a profound understanding of the underlaying mechanism is not yet available. This study focuses on the NiSi2-Si interface, which is studied using the NEGF formalism. Based on the calculated transmission spectra, the transfer characteristic of a reconfigurable transistor is obtained using a simplified approach. Even though this model strongly simplifies the electrostatic environment in a transistor, very good agreement with experimental devices is demonstrated. The impact of strain on the device characteristic is studied as well. It is shown that the magnitude of electron and hole current can be altered successfully. They can also be tuned to be symmetric, which fits to experimental observations. Finally, new insight into the device functionality is gained based on our calculations of the work functions and effective masses of the isolated NiSi 2 and Si.

Reconfigurable transistors (RFETs) can be switched between electron and hole current by changing the polarity of the gate potential. The device performance of such a transistor is strongly dominated by the contact physics. In this work, the electron transport across the NiSi2-Si interface is studied using the NEGF formalism and density functional theory. A new model is presented which relates the electron transport through the interface to the transfer characteristic of an RFET. The model is compared to experimental data showing good agreement. Based on the model, the influence of strain and the choice of the crystal orientation is discussed. It is demonstrated that best symmetry between electron and hole current is achieved for the <110> orientation. Furthermore, this symmetry can be tuned by strain, which is not possible for the <100> and <112> orientations. A discussion of these differences based on band structure analysis will be given, too.

Scaling down of CMOS faces strong challenges due to which new materials, enhanced functionality and new device concepts have gained importance. These concepts include undoped silicon nanowire based reconfigurable devices which can be programmed as p-FET or n-FET by controlling the electrostatic potential applied across gate. In this work, electrical characterization of undoped sub-20 silicon nanowires (SiNWs) is reported. SiNWs are fabricated on intrinsic SOI substrates in <110> and <100> crystal directions by a top down approach. Hydrogen silsesquioxane (HSQ), a negative tone electron beam resist is used for nano- patterning as well as hard mask for etching. Nanowire etching process is optimized using an inductively coupled plasma (ICP) source and C4F8/SF6/O2 mixed gas recipe at 18 oC. These NWs are oxidized to form a SiO2 shell and subsequently silicidized. For silicidation the SiO2 shell is wet etched at pre-defined positions followed by Nickel(Ni) sputtering and diffusion which yield silicide-silicon(Schottky) junctions. Ni is used for silicidation to selectively control the charge carriers injection at the junctions. Different transport and silicidation progress was observed in <110> and <100> crystal directions.

Reconfigurable transistors (RFETs) can be switched between electron and hole current by changing the polarity of the gate potential. This allows a much higher functionality and hence, logic operations can be realized with fewer transistors. The device performance of such a transistor is strongly dominated by the contact physics. In this work, the electron transport across the NiSi 2 -Si interface is studied using the NEGF formalism and density functional theory, which allows us to consider the atomic structure of the interface. A new model is then presented which relates the electron transport through the interface to the transfer characteristic of an RFET. The model is compared to experimental data, which shows very good agreement, especially with respect to the ratio between electron and hole current (left figure). Based on the model, different structure variations at the interface and their consequences on the device performance are discussed. It is demonstrated that best symmetry between electron and hole current is achieved for the <110> crystal orientation, which is much worse for <100> orientation (right figure). This makes the <110> orientation advantageous for RFETs. Also the influence of strain generated parallel to the interface plane is investigated (right figure). It is shown that strain can be used to tune the symmetry in case of <110> crystal orientation even further. This is entirely different for the <100> crystal orientation, where the highest electron currents are observed for all strain states. In this state, the electron currents are about three orders of magnitude higher than the hole currents. A detailed discussion of these differences based on work function and band structure analysis will be given in our contribution.

The crystal structure of the new ternary phase CuSnTi is determined by full profile Rietveld analysis of the powder diffractogram. 104 reflections were refined to a final RBragg value of 5.60%. CuSnTi crystallizes with the spacegroup P63/mmc and is isostructural to InNi2. The lattice parameters are a=0.439 555(5) nm and c=0.601 505(9) nm

The nickel-carbon system has received increased attention over the past years due to the relevance of nickel as a catalyst for carbon nanotube and graphene growth, where Nickel carbide intermediates may be involved or carbide interface layers form in the end. Nickel-carbon composite thin films comprising Ni3C are especially interesting in mechanical sensing applications. Due to the meta-stability of nickel carbides, formation conditions and the coupling between mechanical and electrical properties are not yet well understood. Using first-principles electronic structure methods, we calculated the elastic properties of Ni3C, Ni2C and NiC, as well as changes in electronic properties under mechanical strain. We observe that the electronic density of states around the Fermi level does not change under the considered strains of up to 1%, which correspond to stresses up to 3GPa. Relative changes in conductivity of Ni3C range up to maximum values of about 10%.

In einer Bevölkerung mit immer älteren und auch kränkeren Patienten nimmt die Zahl der Menschen mit Demenz deutlich zu. Damit stellen sie eine zunehmende Herausforderung an die Betreuung aller Beteiligten dar, sowohl in medizinischer als auch in pflegerischer sowie ethischer und sozialmedizinischer Sicht. Wie stellen wir uns dieser Herausforderung? Wie sehen wir diese Menschen in unserer Mitte? Inwieweit werden und können sie in unsere Gesellschaft integriert werden? Wie gehen wir mit ihnen in Praxis und Krankenhaus um? Wie behandeln wir sie, wie müssten, wie sollten wir sie behandeln? Der 6. Ärztetag am Dom will versuchen, aus medizinischer, medizinisch-psychologischer, sozialer und ethischer Sicht hierzu die Fragen einzugrenzen und erste Antworten zu geben.Grußworte (Bischof Dr. Franz-Peter Tebartz-van Elst, Limburg)Der Blick des Gläubigen führt die notwendige Differenzierung der wissenschaftlichen Fachdisziplinen wieder zusammen: Der ganze Mensch, in jedem Stadium des Lebens, ist einmalig; er besitzt einen Namen, nicht nur ein Krankheitsbild. Ungeachtet seiner körperlich-geistigen Einbußen besitzt er eine Würde, die in seiner Bundespartnerschaft mit Gott wurzelt. Alle Menschen sind aufgerufen, demente Personen als selbstverständlichen Teil unserer Gemeinschaft anzunehmen. Auch Demenz ist Leben.Medizinische Grundlagen und Behandlungsmöglichkeiten der Demenz (Prof. Dr. med. Johannes Pantel und Dr. rer. nat. Julia Haberstroh, Arbeitsbereich Altersmedizin mit Schwerpunkt Psychogeriatrie und klinische Gerontologie, Institut für Allgemeinmedizin der Johann Wolfgang Goethe-Universität Frankfurt am Main)Die Demenzen zählen zu den häufigsten neuropsychiatrischen Erkrankungen des höheren Lebensalters. Demenz ist ein klinisch definiertes Syndrom, dessen Leitsymptomatik eine chronische und zumeist im Alter erworbene organisch bedingte Beeinträchtigung der intellektuellen Leistungsfähigkeit darstellt. In den fortgeschrittenen Stadien geht diese mit einem erheblichen Verlust a

In einer Bevölkerung mit immer älteren und auch kränkeren Patienten nimmt die Zahl der Menschen mit Demenz deutlich zu. Damit stellen sie eine zunehmende Herausforderung an die Betreuung aller Beteiligten dar, sowohl in medizinischer als auch in pflegerischer sowie ethischer und sozialmedizinischer Sicht. Wie stellen wir uns dieser Herausforderung? Wie sehen wir diese Menschen in unserer Mitte? Inwieweit werden und können sie in unsere Gesellschaft integriert werden? Wie gehen wir mit ihnen in Praxis und Krankenhaus um? Wie behandeln wir sie, wie müssten, wie sollten wir sie behandeln? Der 6. Ärztetag am Dom will versuchen, aus medizinischer, medizinisch-psychologischer, sozialer und ethischer Sicht hierzu die Fragen einzugrenzen und erste Antworten zu geben.Grußworte (Bischof Dr. Franz-Peter Tebartz-van Elst, Limburg)Der Blick des Gläubigen führt die notwendige Differenzierung der wissenschaftlichen Fachdisziplinen wieder zusammen: Der ganze Mensch, in jedem Stadium des Lebens, ist einmalig; er besitzt einen Namen, nicht nur ein Krankheitsbild. Ungeachtet seiner körperlich-geistigen Einbußen besitzt er eine Würde, die in seiner Bundespartnerschaft mit Gott wurzelt. Alle Menschen sind aufgerufen, demente Personen als selbstverständlichen Teil unserer Gemeinschaft anzunehmen. Auch Demenz ist Leben.Medizinische Grundlagen und Behandlungsmöglichkeiten der Demenz (Prof. Dr. med. Johannes Pantel und Dr. rer. nat. Julia Haberstroh, Arbeitsbereich Altersmedizin mit Schwerpunkt Psychogeriatrie und klinische Gerontologie, Institut für Allgemeinmedizin der Johann Wolfgang Goethe-Universität Frankfurt am Main)Die Demenzen zählen zu den häufigsten neuropsychiatrischen Erkrankungen des höheren Lebensalters. Demenz ist ein klinisch definiertes Syndrom, dessen Leitsymptomatik eine chronische und zumeist im Alter erworbene organisch bedingte Beeinträchtigung der intellektuellen Leistungsfähigkeit darstellt. In den fortgeschrittenen Stadien geht diese mit einem erheblichen Verlust a