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Physical review / B 107(11), 115136 (2023). doi:10.1103/PhysRevB.107.115136, Time- and angle-resolved photoelectron spectroscopy is employed to study the thermalization of a nonequilibrium carrier distribution in the Dirac cone of graphite generated upon absorption of linearly polarized near-infrared laser pulses. The data reveal a characteristic time constant of (20±3)fs for the decay of a photoinduced momentum anisotropy in the nascent carrier population. Additionally, the nascent carrier spectral peak shows a downshift in energy by ∼100meV within the first 30fs after excitation, which is associated with the emission of strongly coupled A′$_1$ optical phonons at K. In agreement with previous findings for graphene, a pronounced momentum anisotropy is also observed for an intermediate quasithermalized state of the carrier population. A fully thermalized distribution (with respect to energy and momentum) is finally established on a characteristic timescale of (40±10)fs. The results underscore the complexity of carrier thermalization on ultrafast timescales resulting from the interplay of carrier-carrier and carrier-phonon interaction., Published by Inst., Woodbury, NY

Extracellular vesicle (EV) secretion is an important mechanism used by cells to release biomolecules. A common necroptosis effector-mixed lineage kinase domain like (MLKL)-was recently found to participate in the biogenesis of small and large EVs independent of its function in necroptosis. The objective of the current study is to gain mechanistic insights into EV biogenesis during necroptosis. Assessing EV number by nanoparticle tracking analysis revealed an increased number of EVs released during necroptosis. To evaluate the nature of such vesicles, we performed a newly adapted, highly sensitive mass spectrometry-based proteomics on EVs released by healthy or necroptotic cells. Compared to EVs released by healthy cells, EVs released during necroptosis contained a markedly higher number of unique proteins. Receptor interacting protein kinase-3 (RIPK3) and MLKL were among the proteins enriched in EVs released during necroptosis. Further, mouse embryonic fibroblasts (MEFs) derived from mice deficient of Rab27a and Rab27b showed diminished basal EV release but responded to necroptosis with enhanced EV biogenesis as the wildtype MEFs. In contrast, necroptosis-associated EVs were sensitive to Ca

Intergenerational inheritance of immune traits linked to epigenetic modifications has been demonstrated in plants and invertebrates. Here we provide evidence for transmission of trained immunity across generations to murine progeny that survived a sublethal systemic infection with Candida albicans or a zymosan challenge. The progeny of trained mice exhibited cellular, developmental, transcriptional and epigenetic changes associated with the bone marrow-resident myeloid effector and progenitor cell compartment. Moreover, the progeny of trained mice showed enhanced responsiveness to endotoxin challenge, alongside improved protection against systemic heterologous Escherichia coli and Listeria monocytogenes infections. Sperm DNA of parental male mice intravenously infected with the fungus C. albicans showed DNA methylation differences linked to immune gene loci. These results provide evidence for inheritance of trained immunity in mammals, enhancing protection against infections. © 2021, The Author(s), under exclusive licence to Springer Nature America, Inc.

Aim Engage faculty in conversations about their work environment to identify perceptions of their academic work environment (AWE) over a three-year period. Background Research pertaining to the clinical work environment is prevalent, however there is a paucity of research investigating the nursing AWE. Method Fifteen faculty were interviewed and involved with a participatory action research (PAR) study. Results Faculty identified four themes: (1) faculty need to be engaged in defining healthy work environments (HWEs); (2) faculty identified challenges in developing and maintaining a HWE; (3) “time and space” are required to focus on HWE; and (4) respect for colleagues and care of self are essential for maintaining a HWE. Conclusions This study identified characteristics of an AWE. It adds to the existing literature on HWE by including the academic setting. The study findings contributes to nurse educator workforce development by providing practical information for nursing educators, academic administrators, and faculty preceptors. Many future recommendations will continue to add to this body of literature.

We employ time- and angle-resolved photoemission spectroscopy to study the spin- and valley-selective photoexcitation and dynamics of free carriers at the $\overline{\mathit{K}}$ and ${\overline{\mathit{K}}}^{\ensuremath{'}}$ points in singly oriented single-layer ${\mathrm{WS}}_{2}/\mathrm{Au}(111)$. Our results reveal that in the valence band maximum an ultimate valley polarization of free holes of 84% can be achieved upon excitation with circularly polarized light at room temperature. Notably, we observe a significantly smaller valley polarization for the photoexcited free electrons in the conduction band minimum. Clear differences in the carrier dynamics between electrons and holes imply intervalley scattering processes into dark states being responsible for the efficient depolarization of the excited electron population.

Investigating the complex interaction of electrically conductive fluids and magnetic fields is relevant for a variety of applications from basic research in magnetohydrodynamics (MHD) to modeling of industrial processes involving metal melts, such as steel casting and crystal growth. However, experimental studies in this field are often limited by the performance of flow instrumentation for opaque liquids. Commercially available measurement systems usually lack the ability to provide a time-resolved imaging of transient flow structures. We present an ultrasound array Doppler velocimeter (UADV) for flow mapping in opaque liquids near room temperature. It is modular and flexible regarding its measurement configuration, for instance it allows capturing two velocity components in two planes (2d–2c) of 67×67 mm 2 with a frame rate of 30 Hz. It uses up to 9 linear arrays with 25 ultrasound transducers each driven in a parallelized time division multiplex (TDM) scheme. A FPGA-based signal processing allows a continuous realtime operation of the measurement system. Combining the single-component velocity data of each linear array to a 2d–2c flow field demands precise knowledge of the relative geometric position of the transducer arrays. We present a novel method that performs a spatial self-calibration by a mutual time of flight measurement, significantly reducing alignment errors. A measurement example of a magnetically stirred flow of GaInSn in a rectangular container is given. The UADV is applied to experiments in the context of manufacturing crystalline silicon ingots for photovoltaics.

Growth and annealing behavior of epitaxial MnO films on an Au (110)–(1 × 2) substrate have been studied by means of Auger electron spectroscopy, low energy electron diffraction, and scanning tunneling microscopy. MnO (110) films have been successfully grown by Mn evaporation in an oxygen atmosphere at room temperature with subsequent annealing to 750 K. Instead of the expected (110)-like diffraction pattern complex mosaic and facet structures are found depending on annealing conditions. The mosaics are misfit-induced and display along [001] directions a misorientation of ± 1.5°. At temperatures around 850 K, mosaics gradually vanish and simultaneously a saw-tooth-like film morphology develops which is formed by ribbons of narrow (100) and (010) MnO facets. At temperatures above 850 K the film partially dewets from the substrate, and the film transforms to three-dimensional MnO islands that have a roof-like shape where large roof sides and small end sides are composed by {100} and by {111} facets, respectively. The experiments corroborate the theoretical predicted tendency of facet formation of MnO (110) surfaces.

International audience; In this work, we present a pilot experiment in the experimental storage ring (ESR) at GSI devoted to impact parameter sensitive studies of inner shell atomic processes for low-energy (heavy-) ion-atom collisions. The experiment was performed with bare and He-like xenon ions (Xe 54+ , Xe 52+ ) colliding with neutral xenon gas atoms, resulting in a symmetric collision system. This choice of the projectile charge states was made in order to compare the effect of a filled K-shell with the empty one. The projectile and target X-rays have been measured at different observation angles for all impact parameters as well as for the impact parameter range of ∼35–70 fm.

Understanding the complex interaction of conductive fluids and time-varying magnetic fields is the main goal of research in magnetohydrodynamics (MHD). Customized magnetic fields can be used to optimize flows in technical and industrial processes involving liquid metals. For example the performance of batteries with replaceable liquid electrolytes, such as zinc slurry energy storage systems, can be improved by magnetically influencing the flow of the electrolyte. However, necessary experimental studies are often limited by the performance of flow instrumentation for opaque liquids. We present a modular research platform for flow mapping in liquid metals, the phased array ultrasound Doppler velocimeter (PAUDV). It is based on the pulsed-wave ultrasound Doppler principle in combination with the phased array technique to provide an electrically steerable sound field, enabling novel applications in MHD research. The ability to dynamically focus the ultrasound beam allows to resolve smaller flow structures in planar measurements compared to fixed-beam sensors. The PAUDV can be applied to flows in narrow channels and two velocity components can be measured with only one acoustical access via the cross beam technique. Fast electrical traversing of the measurement volume allows to obtain and visualize turbulence statistics. A two-point correlation function can be retrieved by interleaving velocity measurements at two focal points of varying distance. The PAUDV consists of a modular electronics unit with up to eight beamformer cards, capable of driving a total of 256 channels. Each channel can be individually configured regarding the excitation pattern (three-level quantization, 64 samples) and the delay (1.6 ns resolution). Data acquisition and processing is implemented on multiple FPGAs, control and data visualization are performed on a PC. The capabilities of the modular research platform PAUDV are demonstrated on measurements in the alloy gallium-indium-tin at room temperature. Time resolved planar velocity vector maps are shown for a flow in a cubic vessel under the influence of a transient rotation magnetic field.

Although the Bundled Payments for Care Improvement (BPCI) Initiative began generating data in January 2013, it may be years before the data can determine if the BPCI Initiative enhances value without decreasing quality. Private insurers have implemented other bundled payment arrangements for the delivery of total joint arthroplasty in a variety of practice settings. It is important for surgeons to review the early results of the BPCI Initiative and other bundled payment arrangements to understand the challenges and benefits of healthcare delivery systems with respect to total joint arthroplasty. In addition, surgeons should understand methods of cost control and quality improvement to determine the effect of the BPCI Initiative on the value-quality equation with respect to total joint arthroplasty.

A combined experimental and theoretical study on the laser-induced excitation of surface plasmon polaritons (SPP) at well-defined step edges of a gold–vacuum interface is presented. As a relevant parameter determining the coupling efficiency between laser field and SPP, we identify the ratio between step height h and excitation wavelength λ. For specific values of h/λ, an almost complete suppression of SPP excitation is observed, which corresponds to a condition of constructive interference between the waves reflected at the top and bottom of the step. Experiment and theory show, furthermore, that next to the amplitude also the phase of the SPP is affected by the superposition.

Twenty-six bone marrow transplantations were performed at the West Germany Tumour Centre at Essen between December 1975 and December 1981. Three patients had aplastic anaemia, 23 acute leukaemia. Of the leukaemia patients 13 had a recurrence and ten were in full remission at the time of the transplantation. Two of the patients with a recurrence received deep-frozen autologous marrow from the remission phase. One patient with aplastic anaemia had an identical twin as donour, while all other patients received allogeneic marrow from histocompatible family members. Eleven patients are still alive, all three of those with aplastic anaemia, one of those with leukaemia in a recurrence, and seven of those with acute leukaemia in full remission. Two of the survivors have a chronic graft-host reaction, but the others are symptom-free, after an observation period of up to four years. Main causes of death were leukemic recurrence (6), infection (5), and graft-host reaction (2). It would seem that at present bone marrow transplantation offers the best chance of a cure for severe aplastic anaemic and acute leukaemia in adults, but only if transplantation is undertaken early and not in the end-stage of the disease.

Eight healthy probands received 1.0 to 1.3 g ethanol per kg body weight within a period of 30 minutes. The average hourly elimination rate of ethanol during the postresorptive phase was found to be 0.18 g/l. No significant increase in the elimination rate was seen either after administration of 200 mg metoprolol per day in slow release form for a period of one week, or after a single dose of 200 mg metoprolol in standard formulation taken at the beginning of ethanol ingestion. On the other hand, long-term administration of metoprolol resulted in a steeper rise and a delayed decrease of blood alcohol concentration. Simultaneous intake of metoprolol and of alcohol in high dosage should be avoided.

In various industrial processes involving liquid metals time-dependent magnetic fields are used for flow control, e. g. during the solidification process of silicon to improve the quality and efficiency of wafers. In order to investigate the interactions between conductive fluids and spatiotemporally varying magnetic fields numerical simulations are performed. The numerical models are verified at model experiments with low-melting alloys. A suitable measurement technique for flow mapping in such model experiments is ultrasound Doppler velocimetry (UDV). We present the Phased Array Ultrasound Doppler Velocimeter (PAUDV), which extends the conventional UDV with the ability to dynamically steer and focus the acoustic field. The custom host software for control and signal processing allows to conduct wide range of different experiments, e. g. two-point correlation in turbulent flows or the measurement of two velocity components with a single acoustic access. Experimental results from 2d-2c measurements and acquired two-point correlations are shown.

The production of high quality solar cells requires a deep understanding of the solidification process. Especially when time-dependent magnetic fields are used to improve the material and heat transfer in the melt, the resulting flow structures are complex and unsteady. Hence, numerical simulations are used to gain an insight into the melt flow. For the calibration of the numerical simulations, model experiments using liquid metals at room temperature are used. The melt flow is strongly influenced by the melt height, that constantly decreases during a solidification process. Hence, measuring the position and the shape of the solidification front is required for an understanding of the melt flow. Furthermore a comprehensive flow mapping of complex and unsteady flow phenomena is necessary. Commercial flow instrumentation systems usually utilize only one or a few single element probes that are operated strictly in sequential multiplex. This leads to low frame rates and limits their application to quasi-static flow fields.

International audience; In this contribution, we present an experimental and theoretical study of the proton- and electron- impact excitation effects in helium-like uranium ions in relativistic collisions with different gaseous targets. The experiment was carried out at the experimental storage ring at GSI Darmstadt. Our experimental results are in agreement with predictions of the state-of-the art theory which treats both processes within the relativistic framework.

Experimental studies in the field of magnetohydrodynamics (MHD) involving complex 3d flows are often limited by the performance of flow instrumentation for opaque liquids. We present a modular research platform for flow mapping in liquid metals, the phased array ultrasound Doppler velocimeter (PAUDV). It is based on the pulsed-wave ultrasound Doppler principle in combination with the phased array technique to provide an electrically steerable sound field, enabling novel applications in MHD research. The ability to dynamically focus and steer the ultrasound beam allows to resolve smaller flow structures compared to fixed-beam sensors. Two velocity components can be measured with only one acoustical access via the cross beam technique. Fast electrical traversing of the measurement volume allows to obtain and visualize turbulence statistics. A two-point correlation function can be retrieved by interleaving velocity measurements at two focal points of varying distance quasi-simultaneously.

A comparative expression proteome analysis was carried out by analyzing differential expression patterns of pulse-labelled proteins on two-dimensional gels under standard conditions and during purine nucleotide starvation, followed by mass spectrometric identification of regulated proteins. Based upon the expression patterns, three stimulons could be identified in Lactococcus lactis subsp. cremoris. The Psu proteins (purine starvation up-regulated) had increased synthesis during purine depletion in a purine auxotroph. Among these proteins were enzymes of the purine biosynthesis pathways (PurE, PurS, PurM, PurL), and enzymes involved in the generation of C1 units (GlyA, Fhs). C1 units are primarily required for purine biosynthesis. Upon analysis of the nucleotide sequence preceding the structural genes for these proteins in the L. lactis IL1403 genome sequence showed that all contained PurBox-Pribnov box structures resembling the PurR activated promoters for the purDEK and purCSQLF operons. Most, and possibly all members of the Psu stimulon are thus members of the PurR regulon. Five Psu proteins could not be identified. The second stimulon, the Psd stimulon (purine starvation decreased), whose members are down-regulated during purine depletion, contained proteins related to protein synthesis (PpsB, EF-TS, trigger factor), or to GTPases (FtsZ, EF-TS); or are involved in energy metabolism (GapB, CcpA). No common regulatory elements could be found for members of this stimulon. Two Psd proteins escaped identification. The last, Dcu (decoynine up-regulated), stimulon contained proteins whose synthesis escaped the severe general depression during inhibition of the GMP synthetase by decoynine. This regulon was comprised of mostly glycolytic enzymes (fructose bisphosphate aldolase, enolase, pyruvate kinase) and translation elongation factors (GTPases: EF-TU, EF-G). Two Dcu proteins could not be identified. Out of 28 proteins subjected to mass spectrometry, 19 could be readily identified despite the fact that only the genome sequence of a strain of L. lactis subsp. lactis was available. The two subspecies share about 85% sequence identity, comparable to the genetic distance between Escherichia coli and Salmonella typhimurium. A success rate of 68% indicates that it may be feasible to perform proteomics based upon genomic sequences of relatives outside the genus.

Investigating the complex interaction of conductive fluids and magnetic fields is relevant for a variety of applications from basic research in magnetohydrodynamics (MHD) to modeling industrial processes involving metal melts, such as the crystal growth process in the photovoltaic industry. This enables targeted optimizations of the melt flow and allows to significantly increase the yield and energy e ffi ciency of industrial processes. However, experimental studies in this field are often limited by the performance of flow instrumentation for opaque liquids. We present an ultrasound array Doppler velocimeter (UADV) for flow mapping in opaque liquids at room temperature. It is modular and flexible regarding its measurement configuration, for instance it allows capturing two velocity components in two planes (2 d − 2 c ). It uses up to 9 linear arrays with a total element count of 225, driven in a parallelized time division multiplex (TDM) scheme. A FPGA-based signal pre-processing allows to handle the massive data bandwidth of typ. 1.2 GB/s and enables a continuous and near-realtime operation of the measurement system. The capabilities of the UADV system are demonstrated in a basic MHD research experiment with a metal melt (GaInSn) in a cubic container of (67 mm)3. The flow induced by a rotating magnetic field is captured with a temporal resolution of 250 ms for the horizontal and vertical central cross-section of the cube.

International audience; We have studied the excitation of H-like and He-like uranium (U91+ and U90+) in relativistic collisions with gaseous targets by observing the subsequent x-ray emission. The experiment was conducted at the ESR storage ring of the GSI accelerator facility in Darmstadt, Germany. The measurements were performed with a newly developed multi-phase target at different collision energies. This enabled us to explore the proton (nucleus) impact excitation as well as the electron impact excitation processes in the relativistic collisions. The large fine-structure splitting in uranium allowed us to unambiguously resolve excitation to different L-shell levels. Moreover, information about the population of different magnetic sublevels has been obtained via an angular differential study of the decay photons associated with the subsequent de-excitation process. The experimental results are compared with calculations performed within the relativistic framework including excitation mechanisms due to both protons (nucleus) and electrons.

The quality of silicon ingots for photovoltaics can be improved by applying time-varying magnetic fields during the solidification process. Their influence on the material and heat transfer in the molten silicon is investigated by means of numerical simulation and laboratory-scale model-experiments with lowmelting metals. Ultrasound Doppler velocimetry is suitable for flow investigations of opaque liquids. While conventional systems using transducers with fixed sound field provide only limited resolution, our approach is to use a phased array (PA) with the ability to focus and steer its acoustic field. We present a phased array ultrasound Doppler velocimeter (PAUDV) for flow mapping and novel measurement methods like two-point correlation of turbulent flows. The PAUDV is a modular platform with 256 independent controllable channels. Each channel is capable of transmitting pulse bursts with a peak-to-peak amplitude of 200 V, a frequency typically ranging between 1 and 10 MHz and a burst length of one to sixteen periods. The bursts across all channels can be aligned and delayed with a resolution of 1.6 ns to each other with a maximum repition frequency of approx. 60 kHz. The PAUDV is a modular system consisting of two backplanes, one master card (control module) and up to eight transceiver cards with 32 channels each. A measurement example of the sound field from a designed phased array is given, which shows that the achievable lateral resolution is better than 1.5 mm for that system configuration.

Objective: To review published algorithms for guiding the use of methylphenidate (MPH) in the treatment of Attention-Deficit/Hyperactivity Disorder (ADHD) in children and adolescents. Methods: A consensus roundtable of 12 experts was convened to review the evidence for the safety and efficacy of MPH in the treatment of ADHD, as well as the published algorithms and practice guidelines for using MPH. The experts reviewed the algorithms for practicality and acceptability by clinicians. Results: Algorithms that included MPH commonly selected it as the initial medication to be employed in the treatment of children with ADHD. Factors involved included its high efficacy, good safety record, and the ubiquitous nature of its appearance in the ADHD treatment literature. Conclusions: MPH should be considered as the first medication to be used in a treatment algorithm for children and adolescents with ADHD.

Experimental evidence is presented for an enhanced thermoelectric figure of merit ZT=σS2T/λ (where σ is the electrical conductivity, S the thermopower, T the temperature, and λ is the thermal conductivity) by a reduction of the thermal conductivity λ in PbTe- and Bi2Te3-superlattices (SLs) parallel to the layer planes. Data on thermoelectric properties of Bi2Te3/Bi2(SexTe1−x)3-SLs, of PbTe-based doping SLs, and PbTe/PbSe0.2Te0.8-SLs are presented. In these structures, a decrease of λ was measured compared to the corresponding bulk compounds or homogeneous alloys. Despite a drop of the total power factor σS2 in the SLs in total an enhancement of the figure of merit ZT is found in these highly-doped PbTe and Bi2Te3-based SLs.

This study presents numerical simulations and experiments considering the flow of an electrically conducting fluid inside a cube driven by a rotating magnetic field (RMF). The investigations are focused on the spin-up, where a liquid metal (GaInSn) is suddenly exposed to an azimuthal body force generated by the RMF, and the subsequent flow development. The numerical simulations rely on a semi-analytical expression for the induced electromagnetic force density in an electrically conducting medium inside a cuboid container with insulating walls. Velocity distributions in two perpendicular planes are measured using a novel dual-plane, two-component ultrasound array Doppler velocimeter (UADV) with continuous data streaming, enabling long term measurements for investigating transient flows. This approach allows to identify the main emerging flow modes during the transition from a stable to unstable flow regimes with exponentially growing velocity oscillations using the Proper Orthogonal Decomposition (POD) method. Characteristic frequencies in the oscillating flow regimes are determined in the super critical range above the critical magnetic Taylor number $Ta_c \approx 1.26 \times 10^5$, where the transition from the steady double vortex structure of the secondary flow to an unstable regime with exponentially growing oscillations is detected. The mean flow structures and the temporal evolution of the flow predicted by the numerical simulations and observed in experiments are in very good agreement., Comment: 34 pages, 25 figures, submitted to Physics of Fluids

Herein are described the development and certain properties of a new drug, pyrazinoylguanidine (PZG), intended for use as an adjunct in the treatment of hypertensive patients with type 2 diabetes, formerly called noninsulin dependent diabetes mellitus. PZG is an analog of the potassium sparing diuretic, amiloride. However, in diabetic patients, amiloride exacerbates hyperglycemia and hyperlipidemia, whereas PZG reduces them. In several studies, PZG not only reduced elevated blood pressure in subjects with essential hypertension, but also downregulated the glucose fatty acid cycle in hypertensive patients with type 2 diabetes. PZG was well tolerated in all patients, as well as in normal subjects whose blood pressures and glucose metabolism were unaffected by PZG. However, in normal subjects made hyperglycemic by giving them hydrochlorothiazide, coadministration of PZG returned blood glucose concentrations to normal. Mechanisms for these effects of PZG in human subjects were investigated in both normal Sprague-Dawley rats and rats made diabetic with streptozotocin (STZ). In isolated rat adipocytes stimulated with theophylline, PZG downregulated both lipolysis and cyclic AMP concentrations. PZG, as well as insulin, increased adipose cyclic nucleotide phosphodiesterase activity, whereas theophylline reduced it. In perfused rat liver, PZG decreased gluconeogenesis and cyclic AMP concentrations. Collectively, these studies illustrate how the side effects (toxicity) of certain drugs, such as the tendency of thiazide diuretics to cause hyperglycemia and hyperlipidemia, can be modulated and even reversed by slight changes in the chemical structure of the molecule, specifically by removal of the 3,5-diamino and 6-chloro substituents on the benzene ring of amiloride to produce PZG.

Starting with a 50‐50 wt.% Al‐Ni alloy powder a new process was developed by which an active alumina supported, not pyrophoric Raney-type Ni catalyst is produced. It consists of very finely dispersed nickel of 25‐30 wt.% (specific weight of about 1.2). The Ni is not ferromagnetic. The catalyst is applied in all liquid phase hydrogenations where standard Raney-Ni is used, with the same or higher specific activity. The structure of the catalyst is described using XRD, SAXS, TEM SEM/EDX, and N2-sorption. The catalytic activity measurements were performed in liquid phase hydrogenations at room temperature and atmospheric pressure. ©2000 Elsevier Science B.V. All rights reserved.

In the current nursing educational environment, the need for creative teaching methods in the classroom is being driven by increasing student numbers, less than optimum ratio of faculty to students, and decreased availability of clinical sites. Although skills laboratories have been used for many years, the integration of manikin models with computerized software is relatively new. It has only been within the past 10 years that nursing educators have begun to use these newer simulation models [Nurs Educ Perspect. 2004;25(5):244-248]. The design of these models enables the presentation of a variety of patient conditions and allows instructor control of manikin outcomes in response to student interventions. Several factors determine the complexity of the simulation model chosen by nursing faculty and include such considerations as targeted courses, desired realism, and learning objectives. This article describes a teaching methodology using a childbirth simulator in the clinical education of baccalaureate nursing students during the pediatric/obstetric clinical course.

In this study, the effects of doping with the surface-active elements Ge, Te, Se, As, Sb and Sn in atomic mass contents of 10 to 200 ppm on the texture and drawability of an IF-steel (FeP06, DIN-EN 10130) and an ELC-steel (FeP05, DIN-EN 10130) were investigated. Twenty-six ingots were produced by melting and doping in a vacuum-induction furnace, followed by forging, hot-rolling and cold-rolling. The cold-rolling reduction was e = 72 %. Recrystallization annealing was performed in a batch-annealing simulation furnace. Subsequently, the orlentation distribution function (ODF) and the α, γ, η-fibre textures of both the cold-rolled and recrystallized state were measured by means of an X-ray diffraction goniometer and compared with the undoped reference material. The results indicate that the IF-steel specimens doped with 100 ppm Te and Se show a significantly enhanced γ-fibre {111} -{111} texture compared to the reference specimen. Also the ELC-steel specimens showed a higher γ-fibre by doping with atomic mass contents of 10 to 100 ppm Se and Te. To investigate whether the drawability has been improved, Lankford-value (r m and Δr) measurements by means of tensile tests were applied. The compositions with improved γ-fibre also showed higher r-values and therefore confirmed the results of the texture measurements. Se doping was found to be especially beneficial in texture and drawability for both investigated materials. The growth of selenides and tellurides at the surface of Ti 4 C 2 S 2 - and Ti 2 S- precipitates was observed by means of scanning transmission electron microscope linescans equipped with field emission gun (STEM-FEG). Doping with Sb and Sn rendered no notable improvement of the materials, and Ge and As proved to affect the mechanical properties unfavourably.

Within the German research program Forschungsvorhaben Komponentensicherheit (FKS), irradiation experiments were performed with ferritic reactor pressure vessel (RPV) steels and welds. The materials cover a wide range of chemical composition and initial toughness to achieve different susceptibility to neutron irradiation. Different neutron flux was applied and the neutron exposure extended up to 8×1019 cm−2. The change in material properties was determined by means of tensile, Charpy impact, drop-weight and fracture mechanics tests, including crack arrest. The results have provided more insight into the acting embrittlement mechanisms and shown that the fracture mechanics concept of the Code provides in general an upper bound for the material which can be applied in the safety analysis of the RPV.

In a three-phase study, single oral doses of placebo, followed in 1 week by pyrazinoylguanidine (PZG; 900 mg), followed in 3 weeks by pyrazinoic acid (PZA; 300 mg) were given to 8 normal male subjects. Blood analyses performed 0, 2 and 4 h after administration of placebo or drug revealed that compared to mean 0 h values, PZG and also PZA, but not placebo, decreased mean values for serum glucose, insulin, C-peptide, triglycerides and free fatty acids. In all groups, serum potassium, urea, fibrinogen, high-density lipoprotein and low-density lipoprotein were unchanged. PZA, but not PZG, increased serum uric acid. PZG significantly reduced very-low-density lipoprotein whereas PZA only tended to do so. PZG was well tolerated and without any side effect, but in 7 of the 8 normal volunteers, PZA produced a variable vasomotor response over the blush area of the face and neck lasting from 30 min in 3 subjects to 4 h in 1 subject. Collectively, these results suggest generally similar metabolic responses of normal subjects to PZG and PZA after only a single oral dose of each. Previously, it was unrecognized that acute administration of PZG and PZA could produce such rapid metabolic changes.

This study was designed to determine whether pyrazinoylguanidine (PZG) can attenuate diabetic nephropathy in streptozotocin (STZ)-induced diabetic rats. Diabetes was induced within 1 week after a single intraperitoneal dose of STZ (45 mg/kg in 0.05 mol/l sodium citrate buffer). Diabetic rats were divided into five groups. Each group received by gavage for 24 weeks one of the following: vehicle (saline 10 ml/kg, b.i.d.), PZG (35 mg/kg, b.i.d.), captopril (15 mg/kg, b.i.d.), or hydrochlorothiazide (HCTZ, 20 mg/kg, b.i.d.). Insulin (NPH 7.5 U/day) was given subcutaneously. PZG treatment for 24 weeks reduced mortality and attenuated diabetic nephropathy, as indicated by reduced urinary excretion of total protein (79% of control), low-molecular-weight protein (12% of control), and albumin (60% of control). PZG also preserved renal structure and function. Compared to HCTZ or vehicle-treated rats, STZ-diabetic rats receiving either captopril or insulin exhibited decreased excretion of total protein, low-molecular-weight protein, and albumin, as well as amelioration of renal pathology. Collectively, these results indicate that PZG, as well as captopril and insulin, improved longevity and several indices of diabetic nephropathy in STZ-diabetic rats.

Pyrazinoylguanidine (PZG) is a new antihyperglycemic, antihyperlipidemic drug. The current study reports on the development of an animal model in which the favorable metabolic effects of PZG, previously described in diabetic patients, could be reproduced and investigated. Adult male as well as female Sprague-Dawley rats received a single intraperitoneal dose (50 mg/kg) of streptozotocin (STZ). One week later, they received PZG (50 mg/kg i.p.) twice daily for a week. Compared to vehicle (saline-treated controls), PZG reduced plasma concentrations of glucose by 33-70%, triglycerides by 50-70%, nonesterified fatty acids by 17-27%, cholesterol by 10-50%, and glucagon by 18-20%. Hydrochlorothiazide given in a dose of 20 mg/kg i.p. b.i.d for 1 week induced metabolic effects opposite to those of PZG. In the Zucker fatty rat, PZG also lowered plasma glucose and lipid concentrations. These results indicate that PZG ameliorated the abnormalities of plasma glucose and lipid that characterize STZ-diabetic and Zucker fatty rats.

In isolated rat adipocytes stimulated with theophylline (1 mmol/l), pyrazinoylguanidine (PZG) downregulated both lipolysis and cyclic AMP concentrations, raising the possibility that PZG stimulates adipose insulin-sensitive phosphodiesterase. To investigate this directly, we measured PZG's effects on phosphodiesterase activity in rat adipocytes. PZG (10 mumol/l) as well as insulin (0.1-1 mU) increased adipose phosphodiesterase activity, whereas theophylline reduced it. Also investigated were PZG's effects on gluconeogenesis and cyclic AMP in perfused rat liver where PZG decreased gluconeogenesis and cyclic AMP concentrations.