The development and deployment of FOTOS: a fast observation of trace organics system

Flüchtige organische Bestandteile (engl.: VOC) sind in der Atmosphäre in Spuren vorhanden, spielen aber trotzdem eine wichtige Rolle in der Luftchemie: sie beeinflussen das Ozon der Troposphäre, städtischen Smog, Oxidationskapazität und haben direkte und indirekte Auswirkungen auf die globale Klimaveränderung. Eine wichtige Klasse der VOC sind die Nicht-Methan-Kohlenwasserstoffe (engl.: NMHC), die überwiegend von anthropogenen Quellen kommen. Aus diesem Grund ist für Luftchemiker ein Messinstrument nötig, das die VOC, die NMHC eingeschlossen, mit einer höheren Zeitauflösung misst, besonders für Echtzeitmessungen an Bord eines Forschungsflugzeuges. Dafür wurde das System zur schnellen Beobachtung von organischen Spuren (engl.: FOTOS) entworfen, gebaut für den Einsatz in einem neuen Wissenschaftlichen Flugzeug, das in großen Höhen und über weite Strecken fliegt, genannt HALO. In der Folge wurde FOTOS in zwei Messkampagnen am Boden getestet. FOTOS wurde entworfen und gebaut mit einem speziell angefertigten, automatisierten, kryogenen Probensystem mit drei Fallen und einem angepassten, erworbenen schnellen GC-MS. Ziel dieses Aufbaus war es, die Vielseitigkeit zu vergrößern und das Störungspotential zu verringern, deshalb wurden keine chemischen Trocknungsmittel oder adsorbierenden Stoffe verwendet. FOTOS erreichte eine Probenfrequenz von 5.5 Minuten, während es mindestens 13 verschiedene C2- bis C5-NMHC maß. Die Drei-Sigma-Detektionsgrenze für n- und iso-Pentan wurde als 2.6 und 2.0 pptv ermittelt, in dieser Reihenfolge. Labortests bestätigten, dass FOTOS ein vielseitiges, robustes, hochautomatisiertes, präzises, genaues, empfindliches Instrument ist, geeignet für Echtzeitmessungen von VOC in Probenfrequenzen, die angemessen sind für ein Forschungsflugzeug wie HALO. Um die Leistung von FOTOS zu bestätigen, wurde vom 26. Januar bis 4. Februar 2010 ein Zwischenvergleich gemacht mit dem GC-FID-System am Meteorologischen Observatorium Hohenpeißenberg, einer WMO-GAW-globalen Station. Dreizehn verschiedene NMHC wurden innerhalb des Rahmens der GWA Data Quality Objectives (DQO) analysiert und verglichen. Mehr als 80% der Messungen von sechs C3- bis C5-NMHC erfüllten diese DQO. Diese erste Messkampagne im Feld hob die Robustheit und Messgenauigkeit von FOTOS hervor, zusätzlich zu dem Vorteil der höheren Probenfrequenz, sogar in einer Messung am Boden. Um die Möglichkeiten dieses Instrumentes im Feld zu zeigen, maß FOTOS ausgewählte leichte NMHC während einer Messkampagne im Borealen Waldgebiet, HUMPPA-COPEC 2010. Vom 12. Juli bis zum 12. August 2010 beteiligte sich eine internationale Gruppe von Instituten und Instrumenten an Messungen physikalischer und chemischer Größen der Gas- und Partikelphasen der Luft über dem Borealen Wald an der SMEAR II-Station nahe Hyyttiälä, Finnland. Es wurden mehrere Hauptpunkte von Interesse im Mischungsverhältnis der Alkane und im Isomerenverhätnis von Pentan identifiziert, insbesondere sehr unterschiedliche Perioden niedriger und hoher Variabilität, drei Rauchschwaden von Biomassen-Verbrennung von russischen Waldbränden und zwei Tage mit extrem sauberer Luft aus der Polarregion. Vergleiche der NMHC mit anderen anthropogenen Indikatoren zeigten mehrere Quellen anthropogener Einflüsse am Ort auf und erlaubten eine Unterscheidung zwischen lokalen und weiter entfernten Quellen. Auf einen minimalen natürlichen Beitrag zum 24h-Kreislauf von NOx wurde geschlussfolgert aus der Korrelation von NOx mit Alkanen. Altersschätzungen der Luftmassen durch das Isomerenverhältnis von Pentan wurden erschwert durch sich verändernde Verhältnisse der Quellen und durch Besonderheiten der Photochemie während des Sommers im hohen Norden. Diese Messungen zeigten den Wert des Messens leichter NMHC, selbst in abgelegenen Regionen, als einen zusätzlichen spezifischen Marker von anthropogenem Einfluss.

Palaeo wind system reconstruction of the last glacial period over Europe, using high resolution proxy data and model-data-comparison

The atmosphere is a global influence on the movement of heat and humidity between the continents, and thus significantly affects climate variability. Information about atmospheric circulation are of major importance for the understanding of different climatic conditions. Dust deposits from maar lakes and dry maars from the Eifel Volcanic Field (Germany) are therefore used as proxy data for the reconstruction of past aeolian dynamics.rnrnIn this thesis past two sediment cores from the Eifel region are examined: the core SM3 from Lake Schalkenmehren and the core DE3 from the Dehner dry maar. Both cores contain the tephra of the Laacher See eruption, which is dated to 12,900 before present. Taken together the cores cover the last 60,000 years: SM3 the Holocene and DE3 the marine isotope stages MIS-3 and MIS-2, respectively. The frequencies of glacial dust storm events and their paleo wind direction are detected by high resolution grain size and provenance analysis of the lake sediments. Therefore two different methods are applied: geochemical measurements of the sediment using µXRF-scanning and the particle analysis method RADIUS (rapid particle analysis of digital images by ultra-high-resolution scanning of thin sections).rnIt is shown that single dust layers in the lake sediment are characterized by an increased content of aeolian transported carbonate particles. The limestone-bearing Eifel-North-South zone is the most likely source for the carbonate rich aeolian dust in the lake sediments of the Dehner dry maar. The dry maar is located on the western side of the Eifel-North-South zone. Thus, carbonate rich aeolian sediment is most likely to be transported towards the Dehner dry maar within easterly winds. A methodology is developed which limits the detection to the aeolian transported carbonate particles in the sediment, the RADIUS-carbonate module.rnrnIn summary, during the marine isotope stage MIS-3 the storm frequency and the east wind frequency are both increased in comparison to MIS-2. These results leads to the suggestion that atmospheric circulation was affected by more turbulent conditions during MIS-3 in comparison to the more stable atmospheric circulation during the full glacial conditions of MIS-2.rnThe results of the investigations of the dust records are finally evaluated in relation a study of atmospheric general circulation models for a comprehensive interpretation. Here, AGCM experiments (ECHAM3 and ECHAM4) with different prescribed SST patterns are used to develop a synoptic interpretation of long-persisting east wind conditions and of east wind storm events, which are suggested to lead to an enhanced accumulation of sediment being transported by easterly winds to the proxy site of the Dehner dry maar.rnrnThe basic observations made on the proxy record are also illustrated in the 10 m-wind vectors in the different model experiments under glacial conditions with different prescribed sea surface temperature patterns. Furthermore, the analysis of long-persisting east wind conditions in the AGCM data shows a stronger seasonality under glacial conditions: all the different experiments are characterized by an increase of the relative importance of the LEWIC during spring and summer. The different glacial experiments consistently show a shift from a long-lasting high over the Baltic Sea towards the NW, directly above the Scandinavian Ice Sheet, together with contemporary enhanced westerly circulation over the North Atlantic.rnrnThis thesis is a comprehensive analysis of atmospheric circulation patterns during the last glacial period. It has been possible to reconstruct important elements of the glacial paleo climate in Central Europe. While the proxy data from sediment cores lead to a binary signal of the wind direction changes (east versus west wind), a synoptic interpretation using atmospheric circulation models is successful. This shows a possible distribution of high and low pressure areas and thus the direction and strength of wind fields which have the capacity to transport dust. In conclusion, the combination of numerical models, to enhance understanding of processes in the climate system, with proxy data from the environmental record is the key to a comprehensive approach to paleo climatic reconstruction.rn

A Measurement System Experiment to Evaluate the Nosing-to-nosing Method for Measuring Dimensions of Steps

Non-uniformity of steps within a flight is a major risk factor for falls. Guidelines and requirements for uniformity of step risers and tread depths assume the measurement system provides precise dimensional values. The state-of-the-art measurement system is a relatively new method, known as the nosing-to-nosing method. It involves measuring the distance between the noses of adjacent steps and the angle formed with the horizontal. From these measurements, the effective riser height and tread depth are calculated. This study was undertaken for the purpose of evaluating the measurement system to determine how much of total measurement variability comes from the step variations versus that due to repeatability and reproducibility (R&R) associated with the measurers. Using an experimental design quality control professionals call a measurement system experiment, two measurers measured all steps in six randomly selected flights, and repeated the process on a subsequent day. After marking each step in a flight in three lateral places (left, center, and right), the measurers took their measurement. This process yielded 774 values of riser height and 672 values of tread depth. Results of applying the Gage R&R ANOVA procedure in Minitab software indicated that the R&R contribution to riser height variability was 1.42%; and to tread depth was 0.50%. All remaining variability was attributed to actual step-to-step differences. These results may be compared with guidelines used in the automobile industry for measurement systems that consider R&R less than 1% as an acceptable measurement system; and R&R between 1% and 9% as acceptable depending on the application, the cost of the measuring device, cost of repair, or other factors.

Method of Detecting System Function by Measuring Frequency Response

Real-time battery impedance spectrum is acquired using a one-time record. Fast Summation Transformation (FST) is a parallel method of acquiring a real-time battery impedance spectrum using a one-time record that enables battery diagnostics. An excitation current to a battery is a sum of equal amplitude sine waves of frequencies that are octave harmonics spread over a range of interest. A sample frequency is also octave and harmonically related to all frequencies in the sum. The time profile of this signal has a duration that is a few periods of the lowest frequency. The voltage response of the battery, average deleted, is the impedance of the battery in the time domain. Since the excitation frequencies are known and octave and harmonically related, a simple algorithm, FST, processes the time record by rectifying relative to the sine and cosine of each frequency. Another algorithm yields real and imaginary components for each frequency.

Method of Detecting System Function by Measuring Frequency Response

Methods of rapidly measuring an impedance spectrum of an energy storage device in-situ over a limited number of logarithmically distributed frequencies are described. An energy storage device is excited with a known input signal, and aresponse is measured to ascertain the impedance spectrum. An excitation signal is a limited time duration sum-of-sines consisting of a select number offrequencies. In one embodiment, magnitude and phase of each frequency ofinterest within the sum-of-sines is identified when the selected frequencies and sample rate are logarithmic integer steps greater than two. This technique requires a measurement with a duration of one period of the lowest frequency. In another embodiment, where selected frequencies are distributed in octave steps, the impedance spectrum can be determined using a captured time record that is reduced to a half-period of the lowest frequency.

Method of Detecting System Function by Measuring Frequency Response

Real time battery impedance spectrum is acquired using one time record, Compensated Synchronous Detection (CSD). This parallel method enables battery diagnostics. The excitation current to a test battery is a sum of equal amplitude sin waves of a few frequencies spread over range of interest. The time profile of this signal has duration that is a few periods of the lowest frequency. The voltage response of the battery, average deleted, is the impedance of the battery in the time domain. Since the excitation frequencies are known, synchronous detection processes the time record and each component, both magnitude and phase, is obtained. For compensation, the components, except the one of interest, are reassembled in the time domain. The resulting signal is subtracted from the original signal and the component of interest is synchronously detected. This process is repeated for each component.

The European baseline series in 10 European Countries, 2005/2006--results of the European Surveillance System on Contact Allergies (ESSCA)

BACKGROUND: Continual surveillance based on patch test results has proved useful for the identification of contact allergy. OBJECTIVES: To provide a current view on the spectrum of contact allergy to important sensitizers across Europe. PATIENTS/METHODS: Clinical and patch test data of 19 793 patients patch tested in 2005/2006 in the 31 participating departments from 10 European countries (the European Surveillance System on Contact Allergies' (ESSCA) www.essca-dc.org) were descriptively analysed, aggregated to four European regions. RESULTS: Nickel sulfate remains the most common allergen with standardized prevalences ranging from 19.7% (central Europe) to 24.4% (southern Europe). While a number of allergens shows limited variation across the four regions, such as Myroxylon pereirae (5.3-6.8%), cobalt chloride (6.2-8.8%) or thiuram mix (1.7-2.4%), the differences observed with other allergens may hint on underlying differences in exposures, for example: dichromate 2.4% in the UK (west) versus 4.5-5.9% in the remaining EU regions, methylchloroisothiazolinone/methylisothiazolinone 4.1% in the South versus 2.1-2.7% in the remaining regions. CONCLUSIONS: Notwithstanding residual methodological variation (affecting at least some 'difficult' allergens) tackled by ongoing efforts for standardization, a comparative analysis as presented provides (i) a broad overview on contact allergy frequencies and (ii) interesting starting points for further, in-depth investigation.

Automatic Labeling of Software Components and their Evolution using Log-Likelihood Ratio of Word Frequencies in Source Code

As more and more open-source software components become available on the internet we need automatic ways to label and compare them. For example, a developer who searches for reusable software must be able to quickly gain an understanding of retrieved components. This understanding cannot be gained at the level of source code due to the semantic gap between source code and the domain model. In this paper we present a lexical approach that uses the log-likelihood ratios of word frequencies to automatically provide labels for software components. We present a prototype implementation of our labeling/comparison algorithm and provide examples of its application. In particular, we apply the approach to detect trends in the evolution of a software system.

The Houston Academy of Medicine--Texas Medical Center Library management information system.

A management information system (MIS) provides a means for collecting, reporting, and analyzing data from all segments of an organization. Such systems are common in business but rare in libraries. The Houston Academy of Medicine-Texas Medical Center Library developed an MIS that operates on a system of networked IBM PCs and Paradox, a commercial database software package. The data collected in the system include monthly reports, client profile information, and data collected at the time of service requests. The MIS assists with enforcement of library policies, ensures that correct information is recorded, and provides reports for library managers. It also can be used to help answer a variety of ad hoc questions. Future plans call for the development of an MIS that could be adapted to other libraries' needs, and a decision-support interface that would facilitate access to the data contained in the MIS databases.

An evaluation of the personal response system program for the elderly in Harris County, Texas

The Personal Response System Program at Huffington Center on Aging, Baylor College of Medicine, provides emergency call systems for elderly people living independently in Houston, Texas. The goal of the project was to complete a formative evaluation of the Personal Response System Program. The specific aims of the evaluation were three-fold. One aim was to evaluate participant health status and level of disability. The second aim was to develop a health care cost estimation strategy. Finally, a preliminary cost-effectiveness analysis was completed to evaluate the program's impact on health care costs and health status among the elderly target population. ^ The evaluation was a longitudinal, randomized experimental design. After the screening of 120 volunteers for eligibility, clients were asked to complete a written questionnaire and a monthly health service contact diary. Volunteers were contacted by telephone interviewers to collect health status information from 100 eligible clients (83%) on three occasions during the six months of follow-up. ^ Initially, volunteers were randomized to two experimental groups. The two groups were found to be comparable at the beginning of the study. No significant differences were detected related to health status, level of disability, or history of physician visits at baseline. However, the group with the Personal Response System (PRS) device had more adverse health events, higher IADL scores, more frequent use of walkers, lower average health status scores, and fewer community volunteers hours than the usual care comparison group. ^ The health care costs were estimated based on an algorithm adapted from the American Medical Association guidelines. Average total health care costs for the group with the PRS device ($912) were greater than the usual care group ($464). However, median health care values for the PRS group ($263) were similar to the usual care comparison group ($234). The preliminary findings indicated that the use of the PRS device was not associated with health care cost savings. ^ In the preliminary cost-effectiveness analysis, use of the personal response system was found to be associated with increased mental health status among elderly clients. The cost-effectiveness evaluation indicated that the associated cost for six months was $710 per unit increase in mental component score when the $150 PRS subscription was included. However, clients with the PRS device were found to have a greater decline in physical health status during the six-month follow-up. The beneficial effect on mental health status was found to be in contrast to negative findings associated with changes in physical health status. The implications for future research relate to the need to identify risk factors among geriatric populations to better target groups that would most likely benefit from PRS Program enrollment. ^

Geomorphology and evolution of the late Pleistocene to Holocene fluvial system in the south-eastern Llanos de Moxos, Bolivian Amazon

In the Bolivian Amazon several paleochannel generations are preserved. Their wide spectrum of morphologies clearly provides crucial information on the type and magnitude of geomorphic and hydrological changes within the drainage network of the Andean foreland. Therefore, in this study we mapped geomorphological characteristics of paleochannels, and applied radiocarbon and optically stimulated luminescence dating. Seven paleochannel generations are identified. Significant changes in sinuosity, channel widths and river pattern are observed for the successive paleochannel generations. Our results clearly reflect at least three different geomorphic and hydrological periods in the evolution of the fluvial system since the late Pleistocene. Changes in discharge and sediment load may be controlled by combinations of two interrelated mechanisms: (i) spatial changes and re-organizations of the drainage network in the upper catchment, and/or (ii) climate changes with their associated local to catchment-scale modifications in vegetation cover, and changes in discharge, inundation frequencies and magnitudes, which have likely affected the evolution of the fluvial system in the Llanos de Moxos. In summary, our study has revealed the enormous potential which geomorphic mapping and analysis combined with luminescence based chronologies hold for the reconstruction of the late Pleistocene to recent fluvial system in a large portion of Amazonia.

Intensive care without walls - introduction of a Medical Emergency Team system in a Swiss tertiary care centre.

QUESTIONS UNDER STUDY To improve the response of deteriorating patients during their hospital stay, the University Hospital Bern has introduced a Medical Emergency Team (MET). Aim of this retrospective cohort study is to review the preceding factors, patient characteristics, process parameters and their correlation to patient outcomes of MET calls since the introduction of the team. METHODS Data on patient characteristics, parameters related to MET activation and intervention and patient outcomes were evaluated. A Vital Sign Score (VSS), which is defined as the sum of the occurrence of each vital sign abnormalities, was calculated for all physiological parameters pre MET event, during event and correlation with hospital outcomes. RESULTS A total of 1,628 MET calls in 1,317 patients occurred; 262 (19.9%) of patients with MET calls during their hospital stay died. The VSS pre MET event (odds ratio [OR] 1.78, 95% confidence interval [CI] 1.50-2.13; AUROC 0.63; all p <0.0001) and during the MET call (OR 1.60, 95% CI 1.41-1.83; AUROC 0.62; all p <0.0001) were significantly correlated to patient outcomes. A significant increase in MET calls from 5.2 to 16.5 per 1000 hospital admissions (p <0.0001) and a decrease in cardiac arrest calls in the MET perimeter from 1.6 in 2008 to 0.8 per 1000 admissions was observed during the study period (p = 0.014). CONCLUSIONS The VSS is a significant predictor of mortality in patients assessed by the MET. Increasing MET utilisation coincided with a decrease in cardiac arrest calls in the MET perimeter.

APPLICATION OF THE BRAINSTEM EVOKED RESPONSE (BER) TO NEUROTOXICITY EVALUATION OF THE AUDITORY SYSTEM: ASSESSMENT OF INORGANIC LEAD-INDUCED OTOTOXICITY

An experimental procedure was developed using the Brainstem Evoked Response (BER) electrophysiological technique to assess the effect of neurotoxic substances on the auditory system. The procedure utilizes Sprague-Dawley albino rats who have had dural electrodes implanted in their skulls, allowing neuroelectric evoked potentials to be recorded from their brainstems. Latency and amplitude parameters derived from the evoked potentials help assess the neuroanatomical integrity of the auditory pathway in the brainstem. Moreover, since frequency-specific auditory stimuli are used to evoke the neural responses, additional audiometric information is obtainable. An investigation on non-exposed control animals shows the BER threshold curve obtained by tests at various frequencies very closely approximates that obtained by behavioral audibility tests. Thus, the BER appears to be a valid measure of both functional and neuroanatomical integrity of the afferent auditory neural pathway.^ To determine the usefulness of the BER technique in neurobehavioral toxicology research, a known neurotoxic agent, Pb, was studied. Female Sprague-Dawley rats were dosed for 45 days with low levels of Pb acetate in their drinking water, after which BER recordings were obtained. The Pb dosages were determined from the findings of an earlier pilot study. One group of 6 rats received normal tap water, one group of 7 rats received a solution of 0.1% Pb, and another group of 7 rats received a solution of 0.2% Pb. After 45 days, the three groups exhibited blood Pb levels of 4.5 (+OR-) 0.43 (mu)g/100 ml, 37.8 (+OR-) 4.8 (mu)g/100 ml and 47.3 (+OR-) 2.7 (mu)g/100 ml, respectively.^ The results of the BER recording indicated evoked response waveform latency abnormalities in both the Pb-treated groups when midrange frequency (8 kHz to 32 kHz) stimuli were used. For the most part, waveform amplitudes did not vary significantly from control values. BER recordings obtained after a 30-day recovery period indicated the effects seen in the 0.1% Pb group had disappeared. However, those anomalies exhibited by the 0.2% Pb group either remained or increased in number. This outcome indicates a longer lasting or possibly irreversible effect on the auditory system from the higher dose of Pb. The auditory pathway effect appears to be in the periphery, at the level of the cochlea or the auditory (VIII) nerve. The results of this research indicate the BER technique is a valuable and sensitive indicator of low-level toxic effects on the auditory system.^

The Comprehensive Assessment of Leadership for Learning: A Next Generation Formative Evaluation and Feedback System

Recent developments in federal policy have prompted the creation of state evaluation frameworks for principals and teachers that hold educators accountable for effective practices and student outcomes. These changes have created a demand for formative evaluation instruments that reflect current accountability pressures and can be used by schools to focus school improvement and leadership development efforts. The Comprehensive Assessment of Leadership for Learning (CALL) is a next generation, 360-degree on-line assessment and feedback system that reflect best practices in feedback design. Some unique characteristics of CALL include a focus on: leadership distributed throughout the school rather than as carried out by an individual leader; assessment of leadership tasks rather than perceptions of leadership practice; a focus on larger complex systems of middle and high school; and transparency of assessment design. This paper describes research contributing to the design and validation of the CALL survey instrument.