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In this paper, the authors present a Radio Access Network (RAN) concept for future mobile communication systems beyond 5G. The concept is based on knowledge of the environment. The three conceptual applications RAN authentication, beam steering, and channel estimation are presented and their added value with respect to 6G development goals is outlined. The concept is explained by means of an intralogistic use case of a fully automated warehouse. Based on this, the concrete steps for implementation in a laboratory setup are described and further research steps are shown., Comment: 8 pages, 4 figures, Confercence NGNA 2022

The introduction of new types of frequency spectrum in 6G technology facilitates the convergence of conventional mobile communications and radar functions. Thus, the mobile network itself becomes a versatile sensor system. This enables mobile network operators to offer a sensing service in addition to conventional data and telephony services. The potential benefits are expected to accrue to various stakeholders, including individuals, the environment, and society in general. The paper discusses technological development, possible integration, and use cases, as well as future development areas.

The German government initiated the Network University Medicine (NUM) in early 2020 to improve national research activities on the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) pandemic. To this end, 36 German Academic Medical Centers started to collaborate on 13 projects, with the largest being the National Pandemic Cohort Network (NAPKON). The NAPKON's goal is creating the most comprehensive Coronavirus Disease 2019 (COVID-19) cohort in Germany. Within NAPKON, adult and pediatric patients are observed in three complementary cohort platforms (Cross-Sectoral, High-Resolution and Population-Based) from the initial infection until up to three years of follow-up. Study procedures comprise comprehensive clinical and imaging diagnostics, quality-of-life assessment, patient-reported outcomes and biosampling. The three cohort platforms build on four infrastructure core units (Interaction, Biosampling, Epidemiology, and Integration) and collaborations with NUM projects. Key components of the data capture, regulatory, and data privacy are based on the German Centre for Cardiovascular Research. By April 01, 2022, 34 university and 40 non-university hospitals have enrolled 5298 patients with local data quality reviews performed on 4727 (89%). 47% were female, the median age was 52 (IQR 36-62-) and 50 pediatric cases were included. 44% of patients were hospitalized, 15% admitted to an intensive care unit, and 12% of patients deceased while enrolled. 8845 visits with biosampling in 4349 patients were conducted by April 03, 2022. In this overview article, we summarize NAPKON's design, relevant milestones including first study population characteristics, and outline the potential of NAPKON for German and international research activities.

Face recognition systems are widely deployed for biometric authentication. Despite this, it is well-known that, without any safeguards, face recognition systems are highly vulnerable to presentation attacks. In response to this security issue, several promising methods for detecting presentation attacks have been proposed which show high performance on existing benchmarks. However, an ongoing challenge is the generalization of presentation attack detection methods to unseen and new attack types. To this end, we propose a new T-shirt Face Presentation Attack (TFPA) database of 1,608 T-shirt attacks using 100 unique presentation attack instruments. In an extensive evaluation, we show that this type of attack can compromise the security of face recognition systems and that some state-of-the-art attack detection mechanisms trained on popular benchmarks fail to robustly generalize to the new attacks. Further, we propose three new methods for detecting T-shirt attack images, one which relies on the statistical differences between depth maps of bona fide images and T-shirt attacks, an anomaly detection approach trained on features only extracted from bona fide RGB images, and a fusion approach which achieves competitive detection performance.

The book, designed for teachers of both beginning-level and transitional students of English as a Second Language (ESL), outlines the Guided Language Experience Process (GLEP) model for planning ESL instructional units using the whole language approach. The first section summarizes research that has influenced this model and its implications for teachers. The second section describes the empty model for unit planning and offers instructions on how to use it, including a generic unit plan. A GLEP unit consists of two basic parts: (1) an idea page that outlines the unit theme, focusing and motivational aspects, closure and evaluation plan, concepts, vocabulary, skills (both English language arts and mathematics, science, and social studies content), and resources and materials; and (2) unit planning pages, which further break down the whole into component parts (specific focusing and motivation strategies, input, guided oral practice, reading/writing activities, extended activities for integration, closure and evaluation activities). A series of sample units on comparative folklore, common threads in human experience in different cultures, and pond life are then provided. The final chapter offers more detailed discussion of strategies and terms. A glossary, sample daily lesson plans, list of resources and useful topics, and bibliography are appended. (MSE)

Identifying stabilizing factors in foodwebs is a long standing challenge with wide implications for community ecology and conservation. Here, we investigate the stability of spatially resolved meta-foodwebs with far-ranging super-predators for whom the whole meta-foodwebs appears to be a single habitat. By using a combination of generalized modeling with a master stability function approach, we are able to efficiently explore the asymptotic stability of large classes of realistic many-patch meta-foodwebs. We show that meta-foodwebs with far-ranging top predators are more stable than those with localized top predators. Moreover, adding far-ranging generalist top predators to a system can have a net stabilizing effect. These results highlight the importance of top predator conservation.

The Jacobian matrix of a dynamical system describes its response to perturbations. Conversely, one can estimate the Jacobian matrix by carefully monitoring how the system responds to environmental noise. We present a closed-form analytical solution for the calculation of a system’s Jacobian from a time series. Being able to access the Jacobian enables a broad range of mathematical analyses by which deeper insights into the system can be gained. Here we consider in particular the computation of the leading Jacobian eigenvalue as an early warning signal for critical transitions. To illustrate this approach, we apply it to ecological meta-foodweb models, which are strongly nonlinear dynamical multi-layer networks. Our analysis shows that accurate results can be obtained, although the data demand of the method is still high.

Ein Teilgebiet der theoretischen Ökologie ist die Analyse der Stabilität von Meta-Nahrungsnetzen. Bei Meta-Nahrungs\-netzen handelt es sich um Nahrungsnetze, die in einen räumlichen Kontext eingebettet sind. Ein Nahrungsnetz beschreibt die Räuber-Beute-Interaktionen der verschiedenen Spezies. Der räumliche Kontext ist durch ein Netzwerk von Habitaten gegeben, in dem sich die verschiedenen Spezies ausbreiten können. Ziel der Untersuchung ist es, die Stabilität von Meta-Nahrungsnetzen zu bewerten und Faktoren zu identifizieren, die sich positiv oder negativ auf die Stabilität eines gegebenen Systems auswirken. Einen Ansatz für die lineare Stabilitätsanalyse komplexer, nichtlinearer dynamischer Systeme stellt die generalisierte Methode dar. Im Rahmen dieser wird ein System auf einen gegebenen Gleichgewichtszustand normiert. Dabei ist es nicht nötig die Interaktionsfunktionen des Systems explizit zu definieren, wodurch ungerechtfertigte Annahmen vermieden werden können. Es reicht die Abhängigkeiten der Interaktionen von den verschiedenen Populationen zu spezifizieren. Dadurch ist es möglich die Jacobi-Matrix eines Systems in Abhängigkeit von generalisierten Parametern zu bestimmen, die im Kontext von Meta-Nahrungsnetzen über klare biologische Interpretationen verfügen. Betrachtet man ein homogenes Gleichgewicht eines dynamischen Systems, das in ein räumliches Netzwerk eingebettet ist, so ist es mit Hilfe des Master-Stability-Funktions-Ansatzes möglich das Eigenwertproblem der Jacobi-Matrix, das der linearen Stabilitätsanalyse des Gleichgewichts zugrunde liegt, in zwei Teile zu zerlegen. Der erste Teil ist das Eigenwertproblem der Laplace-Matrix des räumlichen Netzwerks. Der zweite Teil ist ein Eigenwertproblem, das von der lokalen Dynamik des Systems, der Art der räumlichen Kopplung und den Eigenwerten der räumlichen Laplace-Matrix abhängt. Durch diesen Ansatz können diffusionsgetriebene Instabilitäten in diskreten räumlichen Netzwerken in Analogie zu diffusionsgetriebe

Amyloid appearance is a rare event that is promoted in the presence of other aggregated proteins. These aggregates were thought to act by templating the formation of an assembly-competent nucleation seed, but we find an unanticipated role for them in enhancing the persistence of amyloid after it arises. Specifically, Saccharomyces cerevisiae Rnq1 amyloid reduces chaperone-mediated disassembly of Sup35 amyloid, promoting its persistence in yeast. Mathematical modeling and corresponding in vivo experiments link amyloid persistence to the conformationally defined size of the Sup35 nucleation seed and suggest that amyloid is actively cleared by disassembly below this threshold to suppress appearance of the [PSI+] prion in vivo. Remarkably, this framework resolves multiple known inconsistencies in the appearance and curing of yeast prions. Thus, our observations establish the size of the nucleation seed as a previously unappreciated characteristic of prion variants that is key to understanding transitions between prion states.

Einleitung: Epidemiologische Studien zeigen den langfristigen Nutzen körperlicher Aktivität zur Prävention neurologischer Erkrankungen und kognitiver Defizite im Alter auf. Sportliche Betätigung kann jedoch, vor allem bei Ausübung von Kontaktsportarten, auch akute und chronische neuronale Schädigungen durch häufige mechanische Beeinflussungen des Gehirns hervorrufen. NSE und S-100B sind laborchemische Marker, die im Rahmen der Diagnostik von Hirnschädigungen zum Einsatz kommen. Einige Forschungsarbeiten fanden erhöhte Konzentrationen dieser Biomarker nach sportlichen Belastungen ohne offensichtliches Vorliegen von traumatischen Ereignissen oder neurologischer Beeinträchtigungen. Daher stellt sich die Frage, ob entsprechende Norm- bzw. Cut-Off-Werte für NSE und S-100B universell im klinischen Alltag geeignet sind oder durch belastungsinduzierte Einflüsse einer differenzierteren Beurteilung unterzogen werden sollten. In vorliegender Arbeit wird diese Fragestellung anhand der klassischen Ausdauersportarten Laufen und Radfahren untersucht. Ergebnisse und Diskussion: Zunächst erfolgte der Nachweis für die Reproduzierbarkeit von NSE bei Ausdauersportlern für Ruhe- und Belastungsbedingungen. Es wurden keine signifikanten Unterschiede für NSE im Belastungsvergleich von Radfahren und Laufen, wie beim Vergleich verschiedener Laufintensitäten im zeitlichen Verlauf festgestellt. Die denkbare Einflussnahme beim Laufen durch leichte Erschütterungen des Gehirns basierend auf dem Impact beim Bodenkontakt des Fußes, ist offensichtlich irrelevant. Physischer Stress, der durch einen Marathonlauf verursacht wird, führt offensichtlich in der Akutphase nach dem Wettkampf zu einem signifikanten Anstieg von NSE und S-100B, welche im späteren Verlauf wieder auf das Ausgangsniveau abfallen. Dies ist unabhängig von Alter und Geschlecht. Über dem Normwert für Gesunde liegende NSE-Konzentrationen nach einer Marathonbelastung, haben offensichtlich keine pathophysiologischen Auswirkungen oder kli, Introduction: Epidemiological studies show long term benefits of exercise and sports for neurological diseases and cognitive deficits in elderly populations. In contact sports however also acute and chronic neuronal impairment of the brain itself caused by repetitive mechanical impact have been found. NSE and S-100B are biochemical markers used in diagnostics of brain injuries. Through several studies found increased values of theses markers after exercise without evident existence of traumatological occasion or neurological impairment. Whether NSE and S-100B and its corresponding reference- and cut-off-values can be applied in clinical routine or if exercise-induced effects apply for a more sophisticated evaluation, should herein be examined by the effects of traditionally endurance sports running and cycling. Results and discussion: At first the proof for repeatability of NSE in endurance sportsmen at rest and during physical activity was given. When comparing the effects of cycling and running as well as different training intensities in these sports, no significant changes could be noticed. Possible causes of elevated NSE due to slight concussions of the brain based on repetitive impact forces during running are obviously irrelevant. Running a marathon tends to result in a significant raise of NSE and S-100B in the acute period after the competition. The further process shows a decline to the base level independent of age or gender. NSE values above norm values after completing a marathon have clearly no pathophysiological effects or clinical correlates. Thus high NSE- concentrations should be interpreted with caution in clinical praxis. Further marathon specific factors like training, pacing strategy, weather conditions, dysnatraemia show no significant correlations with NSE or S-100B. Clustering emergency cases by diagnosis and running distance revealed no relationships to NSE. Further research with larger populations is necessary, to emphasize the relevance f

Prions modulate cellular phenotypes by adopting alternative folds called amyloid that change their function and act as templates to convert natively folded protein to the amyloid state. The initial appearance of an amyloid is rare but enhanced by the presence of other aggregated proteins. Previous work has suggested this enhancement arises from the ability of pre-existing aggregates to template amyloid assembly but fails to explain all experimental observations. Our studies in S. cerevisiae suggest an alternative role for pre-existing aggregates: the titration of chaperones, which normally act to disassemble nascent amyloid nuclei. Using the [PSI+]/[PIN+] dual prion system, we demonstrate that the presence of [PIN+] reduces the binding of the molecular chaperone Hsp104 to Sup35 amyloid, the determinant of the [PSI+] prion. In turn, this change reduces the fragmentation of Sup35 amyloid, promoting appearance of the [PSI+] prion. Notably, the combination of [PIN+] and reduced levels of Hsp104 can inhibit prion appearance and propagation for some conformational variants of Sup35 amyloid, providing further evidence of titration. Using conformational variants of [PIN+] known to promote different levels of [PSI+] formation, we demonstrate that differential chaperone titration explains differences in [PIN+] variant promotion of [PSI+] induction. Thus, [PIN+] acts as a decoy for chaperones and thereby promotes persistence of nascent aggregates.

Hintergrund: Bei unzureichender Hörgeräteversorgung von hochgradig schwerhörigen Kindern wird im Rahmen der pädaudiologischen Diagnostik u.a. eine Bildgebung mittels CT und MRT zur Beurteilung der Indikation zur Versorgung mit einem Cochlea Implantat (CI) durchgeführt. Die präoperative Abschätzung eines Gewinns mit dem CI ist für Eltern bei der Entscheidung zur OP oft wichtig, für den Arzt jedoch schwer zu beurteilen.Material und Methoden: Um den postoperativen frühen Gewinn durch eine CI-Versorgung einschätzen zu können, wurden bei 87 Kindern retrospektiv anhand der audiologischen und radiologischen Daten nach möglichen Prädiktoren u.a. der Hörnervendicke in der CISS-(constructive interference in steady-state)-Sequenz gesucht. Eingeschlossen wurden Kinder <18 Jahren, die im Zeitraum von 2010 bis 2015 mit einem in CI versorgt wurden. Anhand des präoperativen MRT des Schädels mit CISS-Sequenz wurde die Dicke des N. vestibulocochlearis und des N. cochlearis gemessen und Korrelationen zu den postoperativen audiologischen Ergebnissen im Rahmen der CI-Anpassung zum Zeitpunkt der 2. audioverbalen Therapie untersucht.Ergebnisse: 55 von 87 Kindern erfüllten die Einschlusskriterien. Sie waren zur Implantation 8 Monate bis 16,1 Jahre alt (im Durchschnitt 4,1 Jahre (±44,8 Monate)). Insgesamt wurden 660 Hörnervenmessungen durchgeführt. Die Dicke des N. vestibulocochlearis des erstimplantierten Ohres lag im Durchschnitt bei 1,23 mm (±0,189 mm, Minimum: 0,83 mm, Max.: 1,58 mm) bzw. des N. cochlearis bei 0,80 mm (±0,11 mm; Minimum: 0,60 mm, Max. 1,03 mm). Der frühe Hörerfolg wurde an den Mittelwerten der besten Aufblähkurve berechnet und lag durchschnittlich bei 46,04 dB (±13,65 dB, Minimum: 26 dB, Max. 85 dB).Diskussion: Die bei den Kindern gemessenen Hörnervendicken waren dünner als in einer Studie von Nadol an anatomischen Präparaten von normalhörenden Erwachsenen (Dicke des N. vestibulocochlearis im Durchschnitt bei 2,02 mm (±0,08 mm); die des N. cochlearis bei 1,04 mm (±0,11

Neural specificity refers to the degree to which neural representations of different stimuli can be distinguished. Evidence suggests that neural specificity, operationally defined as stimulus-related differences in functional magnetic resonance imaging (fMRI) activation patterns, declines with advancing adult age, and that individual differences in neural specificity are associated with individual differences in fluid intelligence. A growing body of literature also suggests that regular physical activity may help preserve cognitive abilities in old age. Based on this literature, we hypothesized that exercise-induced improvements in fitness would be associated with greater neural specificity among older adults. A total of 52 adults aged 59–74 years were randomly assigned to one of two aerobic-fitness training regimens, which differed in intensity. Participants in both groups trained three times a week on stationary bicycles. In the low-intensity (LI) group, the resistance was kept constant at a low level (10 Watts). In the high-intensity (HI) group, the resistance depended on participants’ heart rate and therefore typically increased with increasing fitness. Before and after the 6-month training phase, participants took part in a functional MRI experiment in which they viewed pictures of faces and buildings. We used multivariate pattern analysis (MVPA) to estimate the distinctiveness of neural activation patterns in ventral visual cortex (VVC) evoked by face or building stimuli. Fitness was also assessed before and after training. In line with our hypothesis, traininginduced changes in fitness were positively associated with changes in neural specificity. We conclude that physical activity may protect against age-related declines in neural specificity.

The uptake of water by ambient aerosols at elevated relative humidity (RH) is ubiquitous and often results in large changes in particle size. Because the scattered light intensity from aerosols varies as the diameter taken to the sixth power, optical properties such as the aerosol extinction coefficient, single scatter albedo and optical depth will have strong particle size dependence. There are currently no viable techniques available to perform rapid size-resolved hygroscopic growth measurements over particle size and RH ranges relevant to determining ambient aerosol optical properties at ambient humidity. The Phase I efforts have focused on establishing the technical feasibility of a new method to measure size-resolved water uptake by aerosols that employs differential mobility analysis (DMA) in-concert with multiple humidification and optical sizing steps. In the technique, monodisperse dry particles selected by a DMA are optically sized by five optical particle counters (OPC), one operating at the same RH as the DMA and the remaining OPCs operating at different controlled RHs so that the particle growth as a function of RH can be observed. The technical objectives of the Phase I included: development of a model of overall instrument response, development of the particle humidification system design, extension of existing thermodynamic models of particle growth, model calculations of the time-dependent growth and evaporation of droplets, implementation and testing of the iterative technique for determining particle dry and wet refractive indices from the simulated OPC response to DMA-selected dry particles, sensitivity studies of the size and refractive index resolution of the OPC, detailed engineering design development of the DMA-OPC systems, and initial bench-top prototyping of the OPC. In this final report of our Phase I work, we first describe the technical details of the proposed OPC design and then present the major results from our, The original document contains color images. All DTIC reproductions will be in black and white.

The Tandem Differential Mobility Analyzer (TDMA) technique coupled with aerosol humidification has been widely used for studying aerosol hygroscopicity. In this study, we evaluate the performance of a commercial Humidified TDMA (BMI HTDMA, Model 3002) with respect to DMA sizing, relative humidity (RH) control, and growth factor (GF) measurements. Unique features of this particular HTDMA include a diffusionbased particle humidifier, a DMA design allowing selection of particles up to 2 mm diameter at only 5600 volts, and the ability to study the complete deliquescence and efflorescence cycle. The sizing agreement between DMA 1 and 2 was within 2% over the 35 to 500 nm diameter range. The measured TDMA responses agreed well with theoretical calculations. The RH control and stability were tested at a suburban field site in Hong Kong. The system achieved RH equilibrium in less than 4 min when changing the RH set point. With indoor temperature changes of less than 1 degrees C per hour, the RH control of the system was very stable at 90%, within 1% RH deviation, as confirmed by GF measurements on ammonium sulfate (AS) aerosols performed on separate days. The hygroscopic properties of various pure aerosols were examined and the results agreed well with model predictions. The application of the BMI HTDMA for field measurements was also demonstrated. Two modes were resolved from the GF distributions at 90% RH and variable hygroscopic growth with changing RH was observed.

Redox-mediated posttranslational modifications represent a molecular switch that controls major mechanisms of cell function. Nitric oxide (NO) can mediate redox reactions via S-nitrosylation, representing transfer of an NO group to a critical protein thiol. NO is known to modulate neurogenesis and neuronal survival in various brain regions in disparate neurodegenerative conditions. However, a unifying molecular mechanism linking these phenomena remains unknown. Here, we report that S-nitrosylation of myocyte enhancer factor 2 (MEF2) transcription factors acts as a redox switch to inhibit both neurogenesis and neuronal survival. Structure-based analysis reveals that MEF2 dimerization creates a pocket, facilitating S-nitrosylation at an evolutionally conserved cysteine residue in the DNA binding domain. S-Nitrosylation disrupts MEF2-DNA binding and transcriptional activity, leading to impaired neurogenesis and survival in vitro and in vivo. Our data define a molecular switch whereby redox-mediated posttranslational modification controls both neurogenesis and neurodegeneration via a single transcriptional signaling cascade.

During the Eastern Pacific Emitted Aerosol Cloud Experiment (E-PEACE), a plume of organic aerosol was produced by a smoke generator and emitted into the marine atmosphere from aboard the R/V Point Sur. In this study, the hygroscopic properties and the chemical composition of the plumewere studied at plume ages between 0 and 4 h in different meteorological conditions. In sunny conditions, the plume particles had very low hygroscopic growth factors (GFs): between 1.05 and 1.09 for 30 nm and between 1.02 and 1.1 for 150 nm dry size at a relative humidity (RH) of 92 %, contrasted by an average marine background GF of 1.6. New particles were produced in large quantities (several 10 000 cm.-3), which lead to substantially increased cloud condensation nuclei (CCN) concentrations at supersaturations between 0.07 and 0.88 %. Ratios of oxygen to carbon (O : C) andwater-soluble organic mass (WSOM) increased with plume age: From. © 2013 CC Attribution 3.0 License.

Background: Patients suffering from acute type A aortic dissection undergo replacement of the ascending aorta, the proximal hemiarch or complete aortic arch, depending on the extent of the individual pathology. In a subset of these treated patients, secondary pathologies of the distal anastomosis or the remaining distal part of the aorta occur. The treatment of these pathologies is challenging, requiring major surgical re-do procedures with aortic arch replacement under extracorporeal circulation and hypothermic circulatory arrest. Methods: We report our experience of five patients with complex aortic pathologies after previous aortic surgery treated with a single stage re-do hybrid procedure, consisting of bypass grafting of the supraaortic branches off-pump, stent graft placement for endovascular aortic repair (TEVAR) and surgical debranching of the aortic arch. Results: In all patients the surgical vascular grafts and stent grafts were deployed successfully, there were no intraoperative deaths. Four out of five patients were discharged from hospital in good clinical condition. One patient died postoperatively due to cardiac tamponade. In one patient a type I endoleak persisted leading to occlusion of a bypass branch requiring surgical revision at one year after debranching. Conclusion: We discuss the prerequisites, all steps and potential pitfalls of this hybrid aortic arch replacement. The current procedure avoids cardiopulmonary bypass and circulatory arrest, which may benefit early patient outcome; however, patient and device selection plays a key role for immediate success and midterm outcomes. In addition, precise procedural planning and development of customized stents may help to develop this procedure into a true alternative for conventional aortic arch replacement.

A new counterflow virtual impactor (CVI) inlet is introduced with details of its design, laboratory characterisation tests and deployment on an aircraft during the 2011 Eastern Pacific Emitted Aerosol Cloud Experiment (EPEACE). The CVI inlet addresses three key issues in previous designs; in particular, the inlet operates with: (1) negligible organic contamination; (2) a significant sample flow rate to downstream instruments (approx. 15 1 min(-1)) that reduces the need for dilution; and (3) a high level of accessibility to the probe interior for cleaning. Wind tunnel experiments characterised the cut size of sampled droplets and the particle size-dependent transmission efficiency in various parts of the probe. For a range of counter-flow rates and air velocities, the measured cut size was between 8.7-13.1 microns. The mean percentage error between cut size measurements and predictions from aerodynamic drag theory is 1.7 %. The CVI was deployed on the Center for Interdisciplinary Remotely Piloted Aircraft Studies (CIRPAS) Twin Otter for thirty flights during E-PEACE to study aerosol-cloud-radiation interactions off the central coast of California in July and August 2011. Results are reported to assess the performance of the inlet including comparisons of particle number concentration downstream of the CVI and cloud drop number concentration measured by two independent aircraft probes. Measurements downstream of the CVI are also examined from one representative case flight coordinated with shipboard-emitted smoke that was intercepted in cloud by the Twin Otter., Published in the Journal of Atmos. Meas. Tech., v5 p1259-1269, 2012. Continuation of ONR Grant no. N00014-10-1-0200.

1 mei 2010, Contains fulltext : 89625.pdf (publisher's version ) (Closed access), Atrial natriuretic peptide (ANP) stimulates lipid mobilization and lipid oxidation in humans. The mechanism appears to promote lipid mobilization during exercise. We tested the hypothesis that water immersion augments exercise-induced ANP release and that the change in ANP availability is associated with increased lipid mobilization and lipid oxidation. In an open randomized and cross-over fashion we studied 17 men (age 31+/-3.6 years; body mass index 24+/-1.7 kg/m(2); body fat 17+/-6.7%) on no medication. Subjects underwent two incremental exercise tests on a bicycle ergometer. One test was conducted on land and the other test during immersion in water up to the xiphoid process. In a subset (n=7), we obtained electromyography recordings in the left leg. We monitored gas exchange, blood pressure, and heart rate. In addition, we obtained blood samples towards the end of each exercise step to determine ANP, norepinephrine, epinephrine, lactate, free fatty acids, insulin, and glucose concentrations. Heart rate, systolic blood pressure, and oxygen consumption at the anaerobic threshold and during peak exercise were similar on land and with exercise in water. The respiratory quotient was mildly reduced when subjects exercised in water. Glucose and lactate measurements were decreased whereas free fatty acid concentrations were increased with exercise in water. Water immersion attenuated epinephrine and norepinephrine and augmented ANP release during exercise. Even though water immersion blunts exercise-induced sympathoadrenal activation, lipid mobilization and lipid oxidation rate are maintained or even improved. The response may be explained by augmented ANP release.

We report an extensive airborne characterization of aerosol downwind of a massive bovine source in the San Joaquin Valley (California) on two flights during July 2007. The Center for Interdisciplinary Remotely-Piloted Aircraft Studies (CIRPAS) Twin Otter probed chemical composition, particle size distribution, mixing state, sub- and supersaturated water uptake behavior, light scattering properties, and the interrelationship between these parameters and meteorology. Total PM1.0 levels and concentrations of organics, nitrate, and ammonium were enhanced in the plume from the source as compared to the background aerosol. Organics dominated the plume aerosol mass (∼56–64%), followed either by sulfate or nitrate, and then ammonium.

This study analyzes 27 cumuliform and stratiform clouds sampled aboard the CIRPAS Twin Otter during the 2004 International Consortium for Atmospheric Research on Transport and Transformation (ICARTT) experiment. The data set was used to assess cloud droplet closure using (1) a detailed adiabatic cloud parcel model and (2) a state-of-the-art cloud droplet activation parameterization. A unique feature of the data set is the sampling of highly polluted clouds within the vicinity of power plant plumes. Remarkable closure was achieved (much less than the 20% measurement uncertainty) for both parcel model and parameterization. The highly variable aerosol did not complicate the cloud droplet closure, since the clouds had low maximum supersaturation and were not sensitive to aerosol variations (which took place at small particle sizes). The error in predicted cloud droplet concentration was mostly sensitive to updraft velocity. Optimal closure is obtained if the water vapor uptake coefficient is equal to 0.06, but can range between 0.03 and 1.0. The sensitivity of cloud droplet prediction error to changes in the uptake coefficient, organic solubility and surface tension depression suggest that organics exhibit limited solubility. These findings can serve as much needed constraints in modeling of aerosol-cloud interactions in the North America; future in situ studies will determine the robustness of our findings.

During the July 2005 Marine Stratus/Stratocumulus Experiment (MASE) and the August-September 2006 Gulf of Mexico Atmospheric Composition and Climate Study (GoMACCS), the Center for Interdisciplinary Remotely-Piloted Aircraft Studies (CIRPAS) Twin Otter probed aerosols and cumulus clouds in the eastern Pacific Ocean off the coast of northern California and in southeastern Texas, respectively. An on-board particle-into-liquid sampler (PILS) quantified inorganic and organic acid species with e5- min time resolution. Ubiquitous organic aerosol layers above cloud with enhanced organic acid levels were observed in both locations. The data suggest that aqueousphase reactions to produce organic acids, mainly oxalic acid, followed by droplet evaporation is a source of elevated organic acid aerosol levels above cloud. Oxalic acid is observed to be produced more efficiently relative to sulfate as the cloud liquid water content increases, corresponding to larger and less acidic droplets. As derived from large eddy simulations of stratocumulus under the conditions of MASE, both Lagrangian trajectory analysis and diurnal cloudtop evolution provide evidence that a significant fraction of the aerosol mass concentration above cloud can be accounted for by evaporated droplet residual particles. Methanesulfonate data suggest that entrainment of free tropospheric aerosol can also be a source of organic acids above boundary layer clouds.

Measurements were made by a new cloud condensation nuclei (CCN) instrument (CCNC3) during the Atmospheric Radiation Measurement (ARM) Program’s Aerosol Intensive Observational Period (IOP) in May 2003 in Lamont, Oklahoma. An inverse aerosol/CCN closure study is undertaken, in which the predicted number concentration of particles available for activation (NP) at the CCNC3 operating supersaturations is compared to that observed (NO). NP is based on Ko¨hler Theory, with assumed and inferred aerosol composition and mixing state, and the airborne aerosol size distribution measured by the Caltech Dual Automatic Classified Aerosol Detector (DACAD). An initial comparison of NO and NP, assuming the ambient aerosol is pure ammonium sulfate ((NH4)2SO4), results in closure ratios (NP/NO) ranging from 1.18 to 3.68 over the duration of the IOP, indicating that the aerosol is less hygroscopic than (NH4)2SO4. NP and NO are found to agree when the modeled aerosol population has characteristics of an external mixture of particles, in which insoluble material is preferentially distributed among particles with small diameters (<50 nm) and purely insoluble particles are present over a range of diameters. The classification of sampled air masses by closure ratio and aerosol size distribution is discussed in depth. Inverse aerosol/CCN closure analysis can be a valuable means of inferring aerosol composition and mixing state when direct measurements are not available, especially when surface measurements of aerosol composition and mixing state are not sufficient to predict CCN concentrations at altitude, as was the case under the stratified aerosol layer conditions encountered during the IOP.

A series of experiments has been conducted in the Caltech indoor smog chamber facility to investigate the water uptake properties of aerosol formed by oxidation of various organic precursors. Secondary organic aerosol (SOA) from simple and substituted cycloalkenes (C5-C8) is produced in dark ozonolysis experiments in a dry chamber (RH~5%). Biogenic SOA from monoterpenes, sesquiterpenes, and oxygenated terpenes is formed by photooxidation in a humid chamber (~50% RH). Using the hygroscopicity tandem differential mobility analyzer (HTDMA), we measure the diameter-based hygroscopic growth factor (GF) of the SOA as a function of time and relative humidity. All SOA studied is found to be slightly hygroscopic, with smaller water uptake than that of typical inorganic aerosol substances. The aerosol water uptake increases with time early in the experiments for the cycloalkene SOA, but decreases with time for the biogenic SOA. This behavior could indicate competing effects between the formation of more highly oxidized polar compounds (more hygroscopic), and formation of longer-chained oligomers (less hygroscopic). All SOA also exhibit a smooth water uptake with RH with no deliquescence or efflorescence. The water uptake curves are found to be fitted well with an empirical three-parameter functional form. The measured pure organic GF values at 85% RH are between 1.09–1.16 for SOA from ozonolysis of cycloalkenes, 1.01–1.04 for sesquiterpene photooxidation SOA, and 1.06–1.11 for the monoterpene and oxygenated terpene SOA. The GF of pure SOA (GForg) in experiments in which inorganic seed aerosol is used is determined by assuming volume-weighted water uptake (Zdanovskii-Stokes-Robinson or ''ZSR'' approach) and using the size-resolved organic mass fraction measured by the Aerodyne Aerosol Mass Spectrometer. Knowing the water content associated with the inorganic fraction yields GForg values. However, for each precursor, the GForg values computed from different HTDMA-classified dia

Oxalic acid is often the leading contributor to the total dicarboxylic acid mass in ambient organic aerosol particles. During the 2004 International Consortium for Atmospheric Research on Transport and Transformation (ICARTT) field campaign, nine inorganic ions (including SO4 2!) and five organic acid ions (including oxalate) were measured on board the Center for Interdisciplinary Remotely Piloted Aircraft Studies (CIRPAS) Twin Otter research aircraft by a particle-into-liquid sampler (PILS) during flights over Ohio and surrounding areas. Five local atmospheric conditions were studied: (1) cloud-free air, (2) power plant plume in cloud-free air with precipitation from scattered clouds overhead, (3) power plant plume in cloud-free air, (4) power plant plume in cloud, and (5) clouds uninfluenced by local pollution sources. The aircraft sampled from two inlets: a counterflow virtual impactor (CVI) to isolate droplet residuals in clouds and a second inlet for sampling total aerosol. A strong correlation was observed between oxalate and SO4 2! when sampling through both inlets in clouds. Predictions from a chemical cloud parcel model considering the aqueous-phase production of dicarboxylic acids and SO4 2! show good agreement for the relative magnitude of SO4 2! and oxalate growth for two scenarios: power plant plume in clouds and clouds uninfluenced by local pollution sources. The relative contributions of the two aqueous-phase routes responsible for oxalic acid formation were examined; the oxidation of glyoxylic acid was predicted to dominate over the decay of longer-chain dicarboxylic acids. Clear evidence is presented for aqueous-phase oxalic acid production as the primary mechanism for oxalic acid formation in ambient aerosols.

Although continental-scale plumes of Asian dust and pollution reduce the amount of solar radiation reaching the earth's surface and perturb the chemistry of the atmosphere, our ability to quantify these effects has been limited by a lack of critical observations, particularly of layers above the surface. Comprehensive surface, airborne, shipboard, and satellite measurements of Asian aerosol chemical composition, size, optical properties, and radiative impacts were performed during the Asian Pacific Regional Aerosol Characterization Experiment (ACE-Asia) study. Measurements within a massive Chinese dust storm at numerous widely spaced sampling locations revealed the highly complex structure of the atmosphere, in which layers of dust, urban pollution, and biomass-burning smoke may be transported long distances as distinct entities or mixed together. The data allow a first-time assessment of the regional climatic and atmospheric chemical effects of a continental-scale mixture of dust and pollution. Our results show that radiative flux reductions during such episodes are sufficient to cause regional climate change.

On five occasions spanning the Asian Pacific Regional Aerosol Characterization Experiment (ACE-Asia) field campaign in spring 2001, the Multiangle Imaging Spectroradiometer spaceborne instrument took data coincident with high-quality observations by instruments on two or more surface and airborne platforms. The cases capture a range of clean, polluted, and dusty aerosol conditions. With a three-stage optical modeling process, we synthesize the data from over 40 field instruments into layer-by-layer environmental snapshots that summarize what we know about the atmospheric and surface states at key locations during each event. We compare related measurements and discuss the implications of apparent discrepancies, at a level of detail appropriate for satellite retrieval algorithm and aerosol transport model validation. Aerosols within a few kilometers of the surface were composed primarily of pollution and Asian dust mixtures, as expected. Medium- and coarse-mode particle size distributions varied little among the events studied; however, column aerosol optical depth changed by more than a factor of 4, and the near-surface proportion of dust ranged between 25% and 50%. The amount of absorbing material in the submicron fraction was highest when near-surface winds crossed Beijing and the Korean Peninsula and was considerably lower for all other cases. Having simultaneous single-scattering albedo measurements at more than one wavelength would significantly reduce the remaining optical model uncertainties. The consistency of component particle microphysical properties among the five events, even in this relatively complex aerosol environment, suggests that global, satellite-derived maps of aerosol optical depth and aerosol mixture (air-mass-type) extent, combined with targeted in situ component microphysical property measurements, can provide a detailed global picture of aerosol behavior.

A programme has been implemented to increase roof spans under cemented rockfill in underhand cut-and-fill mining of gold at the Murray mine, Nevada. Mineralisation occurs primarily along a deep fault, which caused extensive fracturing and deformation, creating variable rock quality throughout the ore body. Ground support in areas adjacent to the fault consists of rock bolting, shotcreting and backfilling, with bolt spacing averaging 0.6 m in lower rock mass quality areas. Modelling carried out on the effects of stress and deformation induced into backfill due to the undercutting of spans between 4.6 and 11 m showed that a sharp change in behaviour occurred at around 9.1 m, and this was recommended as the maximum span limit. Increasing the backfill spans has led to substantial productivity improvements, giving a doubling of tons of ore/unit length under backfill where the bolting and shotcreting cycles were not required., A programme has been implemented to increase roof spans under cemented rockfill in underhand cut-and-fill mining of gold at the Murray mine, Nevada. Mineralisation occurs primarily along a deep fault, which caused extensive fracturing and deformation, creating variable rock quality throughout the ore body. Ground support in areas adjacent to the fault consists of rock bolting, shotcreting and backfilling, with bolt spacing averaging 0.6 m in lower rock mass quality areas. Modelling carried out on the effects of stress and deformation induced into backfill due to the undercutting of spans between 4.6 and 11 m showed that a sharp change in behaviour occurred at around 9.1 m, and this was recommended as the maximum span limit. Increasing the backfill spans has led to substantial productivity improvements, giving a doubling of tons of ore/unit length under backfill where the bolting and shotcreting cycles were not required.

Klaus-Jürgen Maier & Fritz Brechtel

Hans-Peter Tschorsnig & Fritz Brechtel

The Defense System Acquisition Review Council (DSARC) was established to review a military program's status and make a recommendation to the Secretary of Defense on the program's readiness to transition from one phase into the succeeding phase of the weapons acquisition process. The Air Force is using the Production Readiness Review (PRR) as a technique to prepare for the DSARC III review held prior to the production phase of the weapons acquisition process. This study analyzes 3 major Air Force weapon system programs to compare their PRR program procedures. Responses were analyzed from System Program Offices and AF Plant Representative Offices to determine if differences did exist. Additionally, 10 AF Systems Command production management experts were interviewed to determine if a standard approach is feasible for conducting future PRR programs. The study indicated that the 3 major programs analyzed did apply different procedures in conducting their respective PRR programs. The authors concludes that a standard PRR approach is feasible and the PRR tasks can be grouped into areas of importance.

A field and laboratory experimental test program was conducted at the Mixed Company and Cedar City test sites to determine the effect of specimen size on the strength and deformation of intact and jointed rock. The strength of Cedar City quartz diorite decreased by a factor of four with increasing specimen size; the Kayenta sandstone decreased by a factor of less than two. A large block test was conducted at the Mixed Company site in which deformation and velocity was measured as a function of stress. The in-situ stress conditions were measured at the Mixed Company site and had a marked effect on the seismic wave velocity in the sandstone. In addition, in situ modulus was measured by several different techniques. A constitutive model for jointed rock, incorporating real data, was developed for use in the calculation of rock mass response. The model for the compressive properties consists of a rate dependent model of the Maxwell type while the plastic shear response due to the presence of joints, is accounted for in terms of additional plastic deformation associated with slip on the joint planes.

Competition is looked upon by many as one technique to maximize the return from the procurement dollars available. Many members of Congress recommend the competitive method of purchasing for most Government procurement actions. However, the history of Federal procurement attests to the fact that competitive bidding is inadequate in some situations. Since competitive procurement does not always result in lower prices, program managers, contracting officers, and buyers should understand the conditions which may affect prices and aggressively seek competition for items that may likely result in net savings to the Government. This paper includes a summary of competition theory and recent research conducted in the area of competition by graduate students at the Air Force Institute of Technology (AFIT). Two graduate research projects that addressed competition for weapon system replenishment spare parts are summarized in the paper followed by some concluding observations. (Author), This article is from 'Proceedings of the Federal Acquisition Research Symposium with Theme: Government, Industry, Academe: Synergism for Acquisition Improvement, held at Williamsburg, Virginia on 7-9 December 1983, AD-A137 700, p150-155.

High-strength backfilling in the B-North zone at the Cannon gold mine, central Washington, is being used in sublevel bench and fill mining as it minimises surface subsidence and provides safe operating conditions during pillar mining between backfill pillars that are carrying portions of overburden weight. Pillar recovery between the backfill pillars has been very successful. Undercutting of the zone in 1987-8 has resulted in measured backfill stresses of 2.28 MPa, or 68% of full overburden weight. Low water content and high proportions of coarse aggregate allow in-place strengths of 5.66 MPa to be achieved, with cement contents between 5 and 6%. The design and structural aspects of the backfill are discussed and deformation and stress change data collected during pillar mining are used to compare the design basis to actual backfill response., High-strength backfilling in the B-North zone at the Cannon gold mine, central Washington, is being used in sublevel bench and fill mining as it minimises surface subsidence and provides safe operating conditions during pillar mining between backfill pillars that are carrying portions of overburden weight. Pillar recovery between the backfill pillars has been very successful. Undercutting of the zone in 1987-8 has resulted in measured backfill stresses of 2.28 MPa, or 68% of full overburden weight. Low water content and high proportions of coarse aggregate allow in-place strengths of 5.66 MPa to be achieved, with cement contents between 5 and 6%. The design and structural aspects of the backfill are discussed and deformation and stress change data collected during pillar mining are used to compare the design basis to actual backfill response.

The Carlton Mill operated from 1951, replacing an earlier custom mill nearby which operated from 1907 to 1942, until its closure in 1961. It pioneered new techniques such as fluosolids roasting of concentrates and carbon-in-pulp extraction of gold and silver. The new plant was reopened in 1981 by Texasgulf and Golden Cycle using some of the old equipment. The redesigned process produces a concentrate rather than bullion and is as simple as possible, incorporating a straightforward crushing/grinding, flotation and thickening circuit with a capacity of 300 tons/day., The Carlton Mill operated from 1951, replacing an earlier custom mill nearby which operated from 1907 to 1942, until its closure in 1961. It pioneered new techniques such as fluosolids roasting of concentrates and carbon-in-pulp extraction of gold and silver. The new plant was reopened in 1981 by Texasgulf and Golden Cycle using some of the old equipment. The redesigned process produces a concentrate rather than bullion and is as simple as possible, incorporating a straightforward crushing/grinding, flotation and thickening circuit with a capacity of 300 tons/day.

Fritz Brechtel

Fritz Brechtel

Vendeur : Deflorenne (17..-1848?). Vendeur, Ouvrages avant 1800