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Colloidal quantum dot (CQD) infrared (IR) photodetectors can be fabricated and operated with larger spectral tunability, fewer limitations in terms of cooling requirements and substrate lattice matching, and at a potentially lower cost than detectors based on traditional bulk materials. Silver selenide (Ag2Se) has emerged as a promising sustainable alternative to current state-of-the-art toxic semiconductors based on lead, cadmium, and mercury operating in the IR. However, an impeding gap in available absorption bandwidth for Ag2Se CQDs exists in the short-wave infrared (SWIR) region due to degenerate doping by the environment, switching the CQDs from intrinsic interband semiconductors in the near-infrared (NIR) to intraband absorbing CQDs in the mid-wave infrared (MWIR). Herein, we show that the small molecular p-type dopant 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ) can be used to extract electrons from the 1Sestate of MWIR active Ag2Se CQDs to activate their intrinsic energy gap in the SWIR window. We demonstrate quenching of the MWIR Ag2Se absorbance peak, shifting of nitrile vibrational peaks characteristic of charge-neutral F4-TCNQ, as well as enhanced CQD absorption around ∼2500 nm after doping both in ambient and under air-free conditions. We elucidate the doping mechanism to be one that involves an integer charge transfer akin to doping in semiconducting polymers. These indications of charge transfer are promising milestones on the path to achieving sustainable SWIR Ag2Se CQD photodetectors.

Tailoring nanoscale catalysts to targeted applications is a vital component in reducing the carbon footprint of industrial processes; however, understanding and controlling the nanostructure influence on catalysts is challenging. Molybdenum disulfide (MoS2), a transition metal dichalcogenide (TMD) material, is a popular example of a nonplatinum-group-metal catalyst with tunable nanoscale properties. Doping with transition metal atoms, such as cobalt, is one method of enhancing its catalytic properties. However, the location and influence of dopant atoms on catalyst behavior are poorly understood. To investigate this knowledge gap, we studied the influence of Co dopants in MoS2nanosheets on catalytic hydrodesulfurization (HDS) through a well-controlled, ligand-directed, tunable colloidal doping approach. X-ray absorption spectroscopy and density functional theory calculations revealed the nonmonotonous relationship between dopant concentration, location, and activity in HDS. Catalyst activity peaked at 21% Co:Mo as Co saturates the edge sites and begins basal plane doping. While Co prefers to dope the edges over basal sites, basal Co atoms are demonstrably more catalytically active than edge Co. These findings provide insight into the hydrogenolysis behavior of doped TMDs and can be extended to other TMD materials.

The DNA damage response (DDR) is intertwined with signaling pathways downstream of oncogenic receptor tyrosine kinases (RTKs). To drive research into the application of targeted therapies as radiosensitizers, a better understanding of this molecular crosstalk is necessary. We present here the characterization of a previously unreported MET RTK phosphosite, Serine 1016 (S1016) that represents a potential DDR-MET interface. MET S1016 phosphorylation increases in response to irradiation and is mainly targeted by DNA-dependent protein kinase (DNA-PK). Phosphoproteomics unveils an impact of the S1016A substitution on the overall long-term cell cycle regulation following DNA damage. Accordingly, the abrogation of this phosphosite strongly perturbs the phosphorylation of proteins involved in the cell cycle and formation of the mitotic spindle, enabling cells to bypass a G2 arrest upon irradiation and leading to the entry into mitosis despite compromised genome integrity. This results in the formation of abnormal mitotic spindles and a lower proliferation rate. Altogether, the current data uncover a novel signaling mechanism through which the DDR uses a growth factor receptor system for regulating and maintaining genome stability.

Increasing the number of environmental stressors could decrease ecosystem functioning in soils. Yet this relationship has not been globally assessed outside laboratory experiments. Here, using two independent global standardized field surveys, and a range of natural and human factors, we test the relationship between the number of environmental stressors exceeding different critical thresholds and the maintenance of multiple ecosystem services across biomes. Our analysis shows that having multiple stressors, from medium levels (>50%), negatively and significantly correlates with impacts on ecosystem services and that having multiple stressors crossing a high-level critical threshold (over 75% of maximum observed levels) reduces soil biodiversity and functioning globally. The number of environmental stressors exceeding the >75% threshold was consistently seen as an important predictor of multiple ecosystem services, therefore improving prediction of ecosystem functioning. Our findings highlight the need to reduce the dimensionality of the human footprint on ecosystems to conserve biodiversity and function.

AbstractAmong EvergreenHealth Home Care Service professionals, no coronavirus disease 2019 (COVID-19) cases were reported when they were instructed to use standard, contact, and droplet precautions with eye protection while providing home health care to patients diagnosed with laboratory-confirmed severe acute respiratory coronavirus virus 2 (SARS-CoV-2). These precautions might provide some level of protection against coronavirus disease 2019 (COVID-19) among home healthcare personnel.

The intensive use of pesticides and their subsequent distribution to the environment and non-target organisms is of increasing concern. So far, little is known about the occurrence of pesticides in soils of untreated areas─such as ecological refuges─as well as the processes contributing to this unwanted pesticide contamination. In this study, we analyzed the presence and abundance of 46 different pesticides in soils from extensively managed grassland sites, as well as organically and conventionally managed vegetable fields (60 fields in total). Pesticides were found in all soils, including the extensive grassland sites, demonstrating a widespread background contamination of soils with pesticides. The results suggest that after conversion from conventional to organic farming, the organic fields reach pesticide levels as low as those of grassland sites not until 20 years later. Furthermore, the different pesticide composition patterns in grassland sites and organically managed fields facilitated differentiation between long-term persistence of residues and diffuse contamination processes, that is, short-scale redistribution (spray drift) and long-scale dispersion (atmospheric deposition), to offsite contamination.

To analyze gastroschisis annual incidence, mortality rates, and trends in the Brazilian state of Rio Grande do Sul from the year 2000 to the year 2017.

Understanding the interfacial properties between an atomic layer and its substrate is of key interest at both the fundamental and technological levels. From Fermi level pinning to strain engineering and superlubricity, the interaction between a single atomic layer and its substrate governs electronic, mechanical and chemical properties. Here, we measure the hardly accessible interfacial transverse shear modulus of an atomic layer on a substrate. By performing measurements on bulk graphite, and on epitaxial graphene films on SiC with different stacking orders and twisting, as well as in the presence of intercalated hydrogen, we find that the interfacial transverse shear modulus is critically controlled by the stacking order and the atomic layer–substrate interaction. Importantly, we demonstrate that this modulus is a pivotal measurable property to control and predict sliding friction in supported two-dimensional materials. The experiments demonstrate a reciprocal relationship between friction force per unit contact area and interfacial shear modulus. The same relationship emerges from simulations with simple friction models, where the atomic layer–substrate interaction controls the shear stiffness and therefore the resulting friction dissipation.

Pesticides are applied in large quantities to agroecosystems worldwide. To date, few studies assessed the occurrence of pesticides in organically managed agricultural soils, and it is unresolved whether these pesticide residues affect soil life. We screened 100 fields under organic and conventional management with an analytical method containing 46 pesticides (16 herbicides, 8 herbicide transformation products, 17 fungicides, seven insecticides). Pesticides were found in all sites, including 40 organic fields. The number of pesticide residues was two times and the concentration nine times higher in conventional compared to organic fields. Pesticide number and concentrations significantly decreased with the duration of organic management. Even after 20 years of organic agriculture, up to 16 different pesticide residues were present. Microbial biomass and specifically the abundance of arbuscular mycorrhizal fungi, a widespread group of beneficial plant symbionts, were significantly negatively linked to the amount of pesticide residues in soil. This indicates that pesticide residues, in addition to abiotic factors such as pH, are a key factor determining microbial soil life in agroecosystems. This comprehensive study demonstrates that pesticides are a hidden reality in agricultural soils, and our results suggest that they have harmful effects on beneficial soil life.

CRISPR-Cas9 deletion (CRISPR-del) is the leading approach for eliminating DNA from mammalian cells and underpins a variety of genome-editing applications. Target DNA, defined by a pair of double-strand breaks (DSBs), is removed during nonhomologous end-joining (NHEJ). However, the low efficiency of CRISPR-del results in laborious experiments and false-negative results. By using an endogenous reporter system, we show that repression of the DNA-dependent protein kinase catalytic subunit (DNA-PKcs)—an early step in NHEJ—yields substantial increases in DNA deletion. This is observed across diverse cell lines, gene delivery methods, commercial inhibitors, and guide RNAs, including those that otherwise display negligible activity. We further show that DNA-PKcs inhibition can be used to boost the sensitivity of pooled functional screens and detect true-positive hits that would otherwise be overlooked. Thus, delaying the kinetics of NHEJ relative to DSB formation is a simple and effective means of enhancing CRISPR-deletion.

Two-dimensional transition metal carbides and nitrides (MXenes) have accumulated tremendous interest recently due to their high conductivity and excellent figures of merit in electromagnetic interference shielding and other applications. Large-area freestanding films of MXenes are important for versatility in application; however, alternative processing methods are needed for large-scale production. In this work, we demonstrate fabrication of Ti3C2TxMXene freestanding films through drop-casting onto hydrophobic plastic substrates. Freestanding MXene films prepared using the drop-casting method can be fabricated in large areas (>125 cm2) and thicknesses (23.2 μm), and have smooth surfaces (14 nm RMS roughness) while maintaining high electrical conductivity (~7,000 S cm−1). Moreover, these MXene films can be micropatterned in three dimensions by processing on commercially available microstructured plastics, resulting in a 38% increase in normalized electromagnetic interference shielding efficiency compared with flat films. The results presented here suggest a scalable path toward creating MXene freestanding films for prototypes and industrialization.

With the rapidly expanding pandemic of SARS‐CoV‐2, there is concern that solid organ transplant recipients will be particularly vulnerable to infection and may experience a more severe clinical course. We report four cases of COVID‐19 in solid organ transplant recipients including recipients of kidney, liver, lung, and heart transplants. We describe each patient's medical history including transplantation history, their clinical presentation and workup, and their course from diagnosis to either hospital discharge or to improvement in symptoms. These reports demonstrate a range of symptoms, clinical severity, and disease course in solid organ transplant recipients with COVID‐19, including two hospitalized patients and two patients managed entirely in the outpatient setting. The authors report four cases of SARS‐CoV‐2 infection in kidney, liver, lung, and heart transplant recipients in Seattle, Washington, with a range of disease severity and favorable outcomes.

BackgroundProgrammes for collective smoking cessation, based on the British model Stoptober, are proposed by public health units in many countries. There is a need for data estimating the rate at which participants in these programmes are successful in quitting smoking. We report a prospective study carried out as part of a large-scale collective cessation programme conducted in Switzerland in 2017.Methods1112 participants among the 7008 smokers enrolled in the collective cessation programme were recruited before the start of the attempt. Continuous abstinence was measured 10 days, 3 months and 6 months after the start of the attempt. Participants who dropped out at follow-up were considered to have failed the attempt (worst-case scenario).ResultsThe continuous abstinence rate was at least 37.9% at 10-day follow-up, 18.8% at 3-month follow-up and 13.1% at 6-month follow-up. Similar levels of continuous abstinence as the worst-case scenario were found in sensitivity analyses including those whose quit attempt started before the beginning of the programme and where multiple imputation was used to replace dropouts. Sensitivity analyses using complete cases or an indicator of abstinence which allows occasional lapses found around double the abstinence rates.ConclusionsOur results support the potential usefulness of large-scale collective cessation campaigns and suggest that such programmes based on social networks are promising areas for future smoking cessation programme activity.

The application of a novel UV fs Laser Ablation Ionization Mass Spectrometry approach for chemical depth profiling of low-melting point, high surface roughness SnAg solder bump features is presented. The obtained submicrometer resolved three-dimensional compositional data reveal unprecedented information on the distribution of individual elements inside the solder bump matrix. Moreover, the determination of matrix-matched relative sensitivity coefficients allows the first report on quantitative assessment of the SnAg alloy composition. These results significantly contribute to an in-depth understanding of the SnAg plating process. This experimental procedure may find application in future additive performance screening.

The ability to precisely control the localization of enzymes on a surface is critical for several applications including biosensing, bionanoreactors, and single molecule studies. Despite recent advances, fabrication of enzyme patterns with resolution at the single enzyme level is limited by the lack of lithography methods that combine high resolution, compatibility with soft, polymeric structures, ease of fabrication, and high throughput. Here, a method to generate enzyme nanopatterns (using thermolysin as a model system) on a polymer surface is demonstrated using thermochemical scanning probe lithography (tc-SPL). Electrostatic immobilization of negatively charged sulfonated enzymes occurs selectively at positively charged amine nanopatterns produced by thermal deprotection of amines along the side-chain of a methacrylate-based copolymer film via tc-SPL. This process occurs simultaneously with local thermal quasi-3D topographical patterning of the same polymer, offering lateral sub-10 nm resolution, and vertical 1 nm resolution, as well as high throughput (5.2 × 104μm2/h). The obtained single-enzyme resolution patterns are characterized by atomic force microscopy (AFM) and fluorescence microscopy. The enzyme density, the surface passivation, and the quasi-3D arbitrary geometry of these patterned pockets are directly controlled during the tc-SPL process in a single step without the need of markers or masks. Other unique features of this patterning approach include the combined single-enzyme resolution over mm2areas and the possibility of fabricating enzymes nanogradients.

Research has started to investigate personality traits of social entrepreneurs because such traits in commercial entrepreneurs have been found to affect new venture creation/success. In this exploratory study, we apply the person‐environment fit theory and analyze specific social entrepreneurial personality dimensions (i.e., altruism, empathic concern, personal distress, compassion), and classical entrepreneurial personality dimensions (i.e., need for achievement (nAch), entrepreneurial self‐efficacy (ESE), general self‐efficacy, risk‐taking propensity) to identify differences between prospective social and commercial entrepreneurs. Using a sample of 85 prospective entrepreneurs, results show that prospective social entrepreneurs differ from prospective commercial entrepreneurs in the personality dimensions of personal distress, nAch, ESE, and risk‐taking propensity.

State-of-the-art laser ablation (LA) depth-profiling techniques (e.g. LA-ICP-MS, LIBS, and LIMS) allow for chemical composition analysis of solid materials with high spatial resolution at micro- and nanometer levels. Accurate determination of LA-volume is essential to correlate the recorded chemical information to the specific location inside the sample. In this contribution, we demonstrate two novel approaches towards a better quantitative analysis of LA craters with dimensions at micrometer level formed by femtosecond-LA processes on single-crystalline Si(100) and polycrystalline Cu model substrates. For our parametric crater evolution studies, both the number of applied laser shots and the pulse energy were systematically varied, thus yielding 2D matrices of LA craters which vary in depth, diameter, and crater volume. To access the 3D structure of LA craters formed on Si(100), we applied a combination of standard lithographic and deep reactive-ion etching (DRIE) techniques followed by a HR-SEM inspection of the previously formed crater cross sections. As DRIE is not applicable for other material classes such as metals, an alternative and more versatile preparation technique was developed and applied to the LA craters formed on the Cu substrate. After the initial LA treatment, the Cu surface was subjected to a polydimethylsiloxane (PDMS) casting process yielding a mold being a full 3D replica of the LA craters, which was then analyzed by HR-SEM. Both approaches revealed cone-like shaped craters with depths ranging between 1 and 70 μm and showed a larger ablation depth of Cu that exceed the one of Si by a factor of about 3.

In this contribution highly sensitive and quantitative analytical methodologies based on femtosecond Laser Ablation Ionization Mass Spectrometry (fs-LIMS) for the analysis of model systems and state-of-the-art Cu interconnects are reviewed and discussed. The method development introduces in a first stage a 1D chemical depth profiling approach on electrodeposited Cu films containing periodically confined organic layers. Optimization of measurement conditions on these test platforms enabled depth profiling investigations with vertical resolution at the nm level. In a second stage, a matrix-free laser desorption methodology was developed that allowed for preliminary molecular identification of the embedded organic contaminants beyond elementary composition. These studies provided specific fragmentation markers in the lower mass range, which support a previously proposed reaction mechanism responsible for successful leveling employing a new class of plating additives for Damascene processes. Further combined LIMS and Scanning Auger Microscopy (SAM) studies on through-silicon-vias (TSV) interconnects confirmed the embedment upon plating of the organic additives at the upper side-walls of the TSV channel in the boundary between the Cu seed layer and the electrodeposited Cu.

ABSTRACTThe first step in preservative measures for artworks in airtight showcases is the exclusion of outgassing from construction materials or, at least, limitation of the emissions to a minimum acceptable level if the volatile organic compounds (VOCs) generated may be qualified as harmless. Once it is ascertained that the objects in the showcases are responsible for VOC emissions, a step forward becomes necessary, implying showcase ventilation with air flowing through active sorbent materials. Solid phase micro-extraction (SPME) followed by GC separation and MS identification has been applied for checking the outgassing characteristics of different types of materials used for the construction of airtight showcases, and the method was found particularly attractive in terms of speed and sensitivity, suitable for measurements in presence of low-emitting materials. Sampling could also be done in the case interiors, thus making possible detection and recognition of emissions from art objects within a case. A comprehensive preventive conservation scheme has been further devised by means of active air circulation within the showcase and functional sorbent materials along the flow, for complete suppression of gaseous compounds. Control of the compounds in the air flow and of their filtration efficacy was achieved by direct sampling, also using SPME fibers. Continuous monitoring of the air quality in the showcases has been developed with insertion of a photoionization detector capable of detecting the VOCs in the air by inducing molecular ionization, and measuring the generated photocurrent. The system is not selective, but gives the total concentration, reaching ppb sensitivity with high-quality data. In addition it includes temperature and humidity sensors, making the whole a useful instrument for environment control.

Abstract

Atomically thin graphene exhibits fascinating mechanical properties, although its hardness and transverse stiffness are inferior to those of diamond. So far, there has been no practical demonstration of the transformation of multilayer graphene into diamond-like ultrahard structures. Here we show that at room temperature and after nano-indentation, two-layer graphene on SiC(0001) exhibits a transverse stiffness and hardness comparable to diamond, is resistant to perforation with a diamond indenter and shows a reversible drop in electrical conductivity upon indentation. Density functional theory calculations suggest that, upon compression, the two-layer graphene film transforms into a diamond-like film, producing both elastic deformations and sp2to sp3chemical changes. Experiments and calculations show that this reversible phase change is not observed for a single buffer layer on SiC or graphene films thicker than three to five layers. Indeed, calculations show that whereas in two-layer graphene layer-stacking configuration controls the conformation of the diamond-like film, in a multilayer film it hinders the phase transformation. Indentation in bilayer epitaxial graphene induces its reversible transformation into a diamond-like structure with stiffness and hardness comparable to diamond.

Reproducing in vitro the complex multiscale physical features of human tissues creates novel biomedical opportunities and fundamental understanding of cell−environment interfaces and interactions. While stiffness has been recognized as a key driver of cell behavior, systematic studies on the role of stiffness have been limited to values in the KPa−MPa range, significantly below the stiffness of bone. Here, a platform enabling the tuning of the stiffness of a biocompatible polymeric interface up to values characteristic of human bone is reported, which are in the GPa range, by using extremely thin polymer films on glass and cross‐linking the films using ultraviolet (UV) light irradiation. It is shown that a higher stiffness is related to better adhesion, proliferation, and osteogenic differentiation, and that it is possible to switch on/off cell attachment and growth by solely tuning the stiffness of the interface, without any surface chemistry or topography modification. Since the stiffness is tuned directly by UV irradiation, this platform is ideal for rapid and simple fabrication of stiffness patterns and gradients, thus representing an innovative tool for combinatorial studies of the synergistic effect of tissue environmental cues on cell behavior, and creates new opportunities for next‐generation biosensors, single‐cell patterning, and lab‐on‐a‐chip devices. A novel platform to tune the stiffness of a biocompatible polymeric interface up to values characteristic of the bone tissue (GPa range)  using ultraviolet (UV) cross‐linking is reported. Since cell growth and differentiation are here controlled solely by the UV‐tunable stiffness of the polymer, this platform is ideal for the simple and rapid fabrication of stiffness patterns and gradients for various biomedical applications.

ABSTRACTBackground: L-DOPA is an amino acid precursor to the neurotransmitter dopamine that is extensively used as a prodrug for the treatment of Parkinson’s disease. However, L-DOPA is an unstable compound: when exposed to light or added to aqueous solutions, it may degrade, compromising its therapeutic properties.Methods: In this work, a new type of drug-loaded cyclodextrin-based nanosponge, obtained using molecular imprinting, is described for the prolonged and controlled release of L-DOPA. The molecularly imprinted nanosponges (MIP-NSs) were synthesized by cross-linking β-cyclodextrin with 1,1ʹ-carbonyldiimidazole in DMF in the presence of L-DOPA as a template molecule. TGA, DSC and FTIR analyses were performed to characterize the interactions between L-DOPA and the two nanosponge structures. Quantitative NMR spectroscopy was used to determine the amount and the affinity of L-DOPA entrapped in the nanosponges. The in vitroL-DOPA release kinetics from the NSs were quantitatively determined by HPLC analysis.Results: The MIP-NSs show a slower and more prolonged release profile than the non-imprinted nanosponges. No degradation of the L-DOPA hosted in the MIP-NSs was observed after long-term storage at room temperature.Conclusions: The MIP-NSs are a promising alternative for the storage and controlled delivery of L-DOPA.

The search for novel tools to control magnetism at the nanoscale is crucial for the development of new paradigms in optics, electronics and spintronics. So far, the fabrication of magnetic nanostructures has been achieved mainly through irreversible structural or chemical modifications. Here, we propose a new concept for creating reconfigurable magnetic nanopatterns by crafting, at the nanoscale, the magnetic anisotropy landscape of a ferromagnetic layer exchange-coupled to an antiferromagnetic layer. By performing localized field cooling with the hot tip of a scanning probe microscope, magnetic structures, with arbitrarily oriented magnetization and tunable unidirectional anisotropy, are reversibly patterned without modifying the film chemistry and topography. This opens unforeseen possibilities for the development of novel metamaterials with finely tuned magnetic properties, such as reconfigurable magneto-plasmonic and magnonic crystals. In this context, we experimentally demonstrate spatially controlled spin wave excitation and propagation in magnetic structures patterned with the proposed method.

Poly(vinylacohol) (PVA) is a versatile polymer capable of forming hydrogels useful in a wide range of applications. Hydrogels based on cross-linking of PVA with borax, and able to incorporate organic solvents, have been used in the field of cultural heritage as tool for cleaning the surfaces. Poly(ethylenoxide) (PEO) has been introduced in the formulations of PVA-borax, with the aim of increasing the gel compatibility with organic solvents and of improving the mechanical properties of the materials. The formulations were investigated with rheological characterization, solvent loss measurements and study of the free water through the determination of the Free Water Index. The PEO molecules do not participate in the formation of the network but have been found to be responsible for a decrement of the storage moduli, explained by a spacing between crosslinks and the partial disentanglement of the PVA chains. At the same time PEO produces in the gel an increase of the apparent relaxation time, thus stabilizing the dispersions and enhancing their ability to maintain the shape. Cleaning tests for removal of an acrylic coating on limestone have been also successfully performed. Graphical abstractPVA/borax hydrogels with acetone were studied with cleaning test and rheological measurements and hypothesis on network structure was proposed.

The method of Thermally assisted Hydrolysis and Methylation (THM) was applied to the analysis of plant gums that can be found in artistic and archaeological objects. The main products obtained by THM of gums arabic, cherry, tragacanth, ghatti and karaya are permethylated and partially methylated 3-deoxyaldonic acids, characteristic products obtained from alkaline hydrolysis of monosaccharides. These markers allowed only a preliminary distinction between the different gums because they are not representative of the entire monosaccharides profile. As classification on the basis of sugars quantification is impossible, multivariate data analysis was employed, using the peak areas of THM products as variables. Calculations were performed on several different sets of data, enhancing the capability of the method to differentiate gums, also when submitted to accelerated ageing treatments. A case study on samples coming from ancient Egyptian cartonnagefunerary masks is presented.

Optimization of mass spectrometers using the adaptive particle swarm algorithm (APSA) is described along with implementations for ion optical simulations and various time‐of‐flight (TOF) instruments. The need for in situself optimization is addressed through discussion of the reflectron TOF mass spectrometer (RTOF) on the European Space Agency mission Rosetta. In addition, a tool for optimization of laboratory mass spectrometers is presented and tested on two different instruments. After the application of APSA optimization, a substantial increase in performance for mass spectrometers that have manually been tuned for several weeks or months is demonstrated. Copyright © 2011 John Wiley & Sons, Ltd.

What exactly Wolf von Niebelschütz did as a soldier in a propaganda unit during the wartime years of 1940–1945, and whether the Wehrmacht newspapers he took care of still exist, was not clear until recently. This article brings together all the currently available information on the German writer’s period of service in France and Germany and analyses the articles from the newspapers that were found. Whilst it is clear that the articles written by Niebelschütz are German wartime propaganda, it also becomes clear that the writer’s articles were not nearly as defaming as those of his propaganda unit colleagues. Moreover there were several attempts by Niebelschütz to stop working for the military, as well as clear remarks in letters to his relatives about his aversion to the kind of work he was doing. After his efforts to leave the military failed, he continued to work for the propaganda unit, apparently because he believed that this would be the easiest way to increase his probability of surviving the war.

Nanoscale chemical patterning of different chemical species (amine, thiol, aldehyde, and biotin) in independent nanopatterns is achieved by the iterative application of thermochemical nanolithography (TCNL) to inscribe amine patterns followed by their chemical conversion to other functional groups. Due to the unique chemical stability of the patterns, the resultant substrates can be stored for weeks and subsequently be used for covalent and molecular‐recognition‐based attachment of nano‐objects using standard chemical protocols. In particular, the ability of this method to attach proteins and DNA to the chemical nanopatterns and to create co‐patterns of two distinctive bioactive proteins is demonstrated.

The role of thermal activation for a nanoasperity sliding on a flat surface with low speed is discussed. If the asperity slides in a vacuum, thermal vibrations may excite slipping from an equilibrium position to the next one along the sliding path. This effect is reduced if the velocity increases and leads to a logarithmic increase of friction with the sliding velocity. This is not always the case in a humid environment, where the formation of capillaries between tip and surface acts as an obstacle for thermally activated jumps. Depending on the wettability of the surface, different behaviors are observed. Copyright © 2006 John Wiley & Sons, Ltd.

Water bridges formed through capillary condensation at nanoscale contacts first stretch and then break during contact rupture. Atomic force microscopy (AFM) pull-off experiments performed in air with hydrophilic tips and samples show that stretched nanoscopic water bridges are in mechanical equilibrium with the external pull-off force acting at the contact but not in thermodynamic equilibrium with the water vapor in air. The experimental findings are explained by a theoretical model that considers constant water volume and decrease of water meniscus curvature during meniscus stretching. The model predicts that the water bridge breakup distance will be roughly equal to the cubic root of the water bridge volume. A thermodynamic instability was noticed for large water bridges formed at the contact of a blunt AFM tip (curvature radius of 400 nm) with a flat sample. In this case, experiments showed rise and stabilization of the volume of the water at the contact in about 1 s. For sharp AFM tips (curvature radius below 50 nm), the experiments indicated that formation of stable water bridges occurs in a much shorter time (below 5 ms).

Pt particles and clusters have been electrochemically deposited onto boron-doped diamond thin films supported by silicon wafers (SiBDD). The careful study of the morphology and dispersion of Pt deposits by AFM (air, tapping mode) proves the existence of a small number of preferential diamond sites on which the initially deposited Pt particles are growing fast. The behavior evidenced may result from the high electrical conductivity near some sites, presumably due to a higher local concentration of boron used in the BDD films as doping centers.

The process-based Pasture Simulation Model (PaSim 2.5) has been extended to simulate N2O production and emission from grassland caused by nitrogen inputs from different sources. The model was used to assess the influence of management on N2O emissions, such as the effect of shifts in the amount and timing of fertilizer application. Model performance has been tested against season-long field measurements at two different field sites. Simulation results agreed favourably with measured N2O emission and soil air concentrations, except during an extremely wet period at one site when grass growth was very poor. The results of short-term and long-term simulation runs demonstrated the potential of the model to estimate N2O emission factors under various conditions. During the first growing season, simulated emissions from organic fertilizers were lower than from synthetic fertilizers because more of the nitrogen was used to build up soil organic matter. The relative difference between the fertilizer types became larger with increasing application rate. The difference between fertilizer types was smaller at steady-state when higher soil organic matter content from repeated application of organic fertilizer over time led to enhanced mineralization and N2O emissions. The dependence of simulated N2O emissions on N input was close to linear at low, but non-linear at high fertilization rates. Emission factors calculated from the linear part of the curve suggested that the factors used in the current IPCC method underestimate the long-term effects of changes in fertilizer management. Furthermore the simulations show that N2O emissions caused by nitrogen inputs from the decomposition of harvest losses and from biological fixation in grassland can be considerable and should not be neglected in national emission inventories.

Structural properties of [BaCuOx]2/[CaCuO2]n superconducting superlattices with a number of CaCuO2 layers ranging between 2 and 3 were investigated using synchrotron radiation, by coplanar (symmetrical and asymmetrical) X-ray diffraction and also in grazing incidence geometry. This extensive X-ray diffraction characterisation allowed to confirm the pseudomorphic growth of [BaCuOx]2/[CaCuO2]n superlattices on the SrTiO3 (001)-oriented substrate. Reciprocal space maps in symmetrical configuration, i.e. by specular reflection, showed the effect of a slight miscut of the substrate on the inclination of the rods. Finally, the interface and surface morphology were investigated by diffuse scattering obtaining the in-plane and out-of-plane correlation properties of the interface roughness and these results were compared with the surface roughness measured by atomic force microscopy.

A study of the relationship between structure and growth parameters for existing and candidate carbon-based protective coatings has been carried out. In particular, diamond-like carbon (DLC) and carbon nitride thin films were deposited on silicon wafers by pulsed Nd:YAG laser (wavelength 532nm) ablation of graphite in high vacuum (p=1.5×10−7Pa) and in a nitrogen atmosphere (p=13Pa). The composition (N/C ratio), the structural and electronic properties and the surface morphology of the deposited films were investigated as a function of laser fluence (1–12J/cm2). The highest N/C ratio 0.40 was obtained with a laser fluence of 12J/cm2; for this nitrogen concentration X-ray photoelectron spectroscopy (XPS) reveals an increase of CN bonds instead of CN bonds with respect to lower concentrations.

Hemolytic blood samples are the number one cause for specimen rejection at emergency departments. Triggered by unsuitable blood sampling material or incorrect handling and a related strong vacuum force, hemolytic samples often must be retaken. The objective of this study was to assess whether correct manual aspiration using S-Monovette® could reduce the number of hemolytic samples.

1. In a reaction time situation, the monosynaptic spinal reflex (H reflex) is facilitated before the onset of an electromyographic (EMG) response. The aim of the present investigation was to test if the facilitation can be attributed either to a subliminal depolarization of motoneurones or to an increase of the excitatory effect of the afferent volley reaching the motoneurones. 2. At the onset of an acoustic warning signal, human subjects were required to concentrate on a reaction time task and, in addition, to initiate a steady isometric plantar flexion of medium intensity in both feet. In response to a following visual stimulus, they carried out a ballistic plantar flexion randomly with the right or left foot. At different times after the visual reaction signal, H reflexes were elicited bilaterally. 3. The facilitation of the H reflex was similar in the presence and absence of a steady activation. In addition, the facilitations were similar in absolute amplitude and duration when the stimuli evoking the H reflexes were at threshold intensities, or at an intensity which produced control H reflexes of 60% maximum amplitude. 4. In a second series of experiments, no H reflexes were elicited but the strength of the steady plantar flexion was varied. Premotor time, i.e. the interval between the onset of the visual stimulus and the EMG response, and reaction time, i.e. the interval between the onset of the visual stimulus and the mechanical response, were computed. Neither parameter depended significantly on the intensity of steady flexion and they were the same with steady flexion as without. 5. The rectified EMG records and the torque records were aligned by the end of premotor time. Three‐dimensional displays of average activity as a function of time and steady activation level were computed. No activation before premotor and reaction time was detected which could have been related to the H reflex facilitation. 6. The present results suggest that all motoneurones, in particular those being activated during the voluntary contraction, can contribute to the H reflex facilitation before movement onset and that the basis of this facilitation is an enhanced excitatory effect of the afferent volley elicited by the H reflex stimulus. Mechanisms leading to the facilitation could be removal of presynaptic inhibition at I a terminals or facilitation of interneurones intercalated in polysynaptic components of the reflex pathways.

Following an extended infarction in the territory of the left anterior cerebral artery including the anterior corpus callosum, a 66-year-old right-handed man exhibited an alien hand syndrome on the right side and an ideomotor apraxia of the left hand. In addition to other typical symptoms of frontal lobe lesions, he presented with an interesting difference in the manifestation of perseveration in either hand. In the right hand, the perseveration was part of the alien hand syndrome, whereas in the left hand perseveration showed in the inability to switch promptly from one movement to another on instruction during praxis testing.

During January and August, 1990, 23 cases of early onset Group B Streptococcus(GBS) disease occurred in a Kansas City, MO, hospital with an attack rate of 14/1000 live births, compared with an annual rate of 1.2 cases/1000 live births for 1988 through 1989. Case infants were compared with controls matched by birth weight, race, maternal age and day of delivery and to a second group of infants of mothers colonized with GBS to identify risk factors and consider intervention strategies during the outbreak. The presence of multiple serotypes among the invasive strains suggested that the outbreak was not caused by a common source. Case mothers were more likely than control mothers to have chorioamnionitis, intrapartum fever or rupture of membranes > 12 hours, and premature case infants were more likely to have a history of rupture of membranes before onset of labor. Multiparous mothers of case infants were more likely to have a history of spontaneous abortion (odds ratio, 6.7; 95 confidence interval, 1.0 to 45.9). No single factor could explain the increase in GBS disease. If intrapartum antibiotic prophylaxis had been used for selected GBS carriers based on presence of either rupture of membranes >12 hours, intrapartum maternal fever or preterm labor, 7.4 of all deliveries would have received antibioties and 73 of cases could potentially have been prevented. We conclude that identification of colonized mothers with perinatal risk factors and use of intrapartum antibiotics could be expected to prevent substantial disease during an outbreak of early onset GBS disease.

This paper presents a cascade speed control by state variable feed-back method applied to a cycloconverter-fed synchronous motor. By decoupling the currents control circuits that are referenced in a coordinate system turning with the rotor, one can obtain and simplify two independent major loops concerning respectively the stator flux and the speed. The most important purpose of this paper concerns the study of the three currents control and their decoupling. Nevertheless, the speed control and the flux control are also described.