Entwicklung eines Radio-Immunoassays und Rezeptor-Assays zum Nachweis von Leptin

In der vorliegenden Studie wurde ein Radioliganden-Rezeptor-Bindungstest zum Nachweis des Plasma-Leptin entwickelt und seine Praktikabilität im Vergleich zur Radioimmunologischen Bestimmung überprüft. Zur Gewinnung von AK gegen Leptin wurden Kaninchen mit rekombinantem Leptin der Maus immunisiert. Alle Tiere antworteten mit einer positiven Immunreaktion. Das Antiserum mit dem höchsten Titer kam im Radioimmunoassay in einer Endverdünnung von 1:28000 zum Einsatz, die Kreuzreaktion mit humanem Leptin belief sich auf 100%. Die IC-50 lag um 30 fmol/tube(350µl) humanem Leptin. In der Durchführung der RBT?s kamen Zellen der Erythroleukämie-Zelllinie K562, die sich durch einen besonders hohen Besatz von Leptinrezeptoren auszeichnen, zur Anwendung. 50% Verdrängung des Radioliganden wurden bei ca. 10 fmol/100µl Leptin beobachtet. Mit beiden Nachweismethoden wurde eine positive Beziehung zwischen BMI und Leptinkonzentration im Plasma gefunden. Die Analyse der Meßwerte in einer limitierten Zahl von Patienten deutet darauf hin, daß mit beiden Verfahren vergleichbare Meßergebnisse erzielt werden. Dies läßt, mit Einschränkung, den Schluß zu, daß mit beiden Methoden das biologisch verfügbare Hormon gemessen wird. Angesichts ähnlicher Leistung bei weitaus höherer Praktikabilität des RIA bleibt die Anwendung des RBT speziellen Studien der Rezeptorphysiologie vorbehalten

Coastally Trapped Wind Reversals: Progress toward Understanding

Coastally trapped wind reversals along the U.S. west coast, which are often accompanied by a northward surge of fog or stratus, are an important warm-season forecast problem due to their impact on coastal maritime activities and airport operations. Previous studies identified several possible dynamic mechanisms that could be responsible for producing these events, yet observational and modeling limitations at the time left these competing interpretations open for debate. In an effort to improve our physical understanding, and ultimately the prediction, of these events, the Office of Naval Research sponsored an Accelerated Research Initiative in Coastal Meteorology during the years 1993â 98 to study these and other related coastal meteorological phenomena. This effort included two field programs to study coastally trapped disturbances as well as numerous modeling studies to explore key dynamic mechanisms. This paper describes the various efforts that occurred under this program to provide an advancement in our understanding of these disturbances. While not all issues have been solved, the synoptic and mesoscale aspects of these events are considerably better understood.Most of the authors were supported through the Office of Naval Research Coastal Meteorology Accelerated Research Initiative, one of the authors (WTT) was supported by Program Element 0601153N, Naval Research Laboratory

BAERLIN2014 -The influence of land surface types on and the horizontal heterogeneity of air pollutant levels in Berlin

Urban air quality and human health are among the key aspects of future urban planning. In order to address pollutants such as ozone and particulate matter, efforts need to be made to quantify and reduce their concentrations. One important aspect in understanding urban air quality is the influence of urban vegetation which may act as both emitter and sink for trace gases and aerosol particles. In this context, the "Berlin Air quality and Ecosystem Research: Local and long-range Impact of anthropogenic and Natural hydrocarbons 2014" (BAERLIN2014) campaign was conducted between 2 June and 29 August in the metropolitan area of Berlin and Brandenburg, Germany. The predominant goals of the campaign were (1) the characterization of urban gaseous and particulate pollution and its attribution to anthropogenic and natural sources in the region of interest, especially considering the connection between biogenic volatile organic compounds and particulates and ozone; (2) the quantification of the impact of urban vegetation on organic trace gas levels and the presence of oxidants such as ozone; and (3) to explain the local heterogeneity of pollutants by defining the distribution of sources and sinks relevant for the interpretation of model simulations. In order to do so, the campaign included stationary measurements at urban background station and mobile observations carried out from bicycle, van and airborne platforms. This paper provides an overview of the mobile measurements (Mobile BAERLIN2014) and general conclusions drawn from the analysis. Bicycle measurements showed micro-scale variations of temperature and particulate matter, displaying a substantial reduction of mean temperatures and particulate levels in the proximity of vegetated areas compared to typical urban residential area (background) measurements. Van measurements extended the area covered by bicycle observations and included continuous measurements of O3, NOx, CO, CO2 and point-wise measurement of volatile organic compounds (VOCs) at representative sites for traffic- and vegetation-affected sites. The quantification displayed notable horizontal heterogeneity of the short-lived gases and particle number concentrations. For example, baseline concentrations of the traffic-related chemical species CO and NO varied on average by up to ±22.2 and ±63.5 %, respectively, on the scale of 100 m around any measurement location. Airborne observations revealed the dominant source of elevated urban particulate number and mass concentrations being local, i.e., not being caused by long-range transport. Surface-based observations related these two parameters predominantly to traffic sources. Vegetated areas lowered the pollutant concentrations substantially with ozone being reduced most by coniferous forests, which is most likely caused by their reactive biogenic VOC emissions. With respect to the overall potential to reduce air pollutant levels, forests were found to result in the largest decrease, followed by parks and facilities for sports and leisure. Surface temperature was generally 0.6–2.1 °C lower in vegetated regions, which in turn will have an impact on tropospheric chemical processes. Based on our findings, effective future mitigation activities to provide a more sustainable and healthier urban environment should focus predominantly on reducing fossil-fuel emissions from traffic as well as on increasing vegetated areas

A modified atmospheric non-hydrostatic model on low aspect ratio grids

© The Author(s), 2012. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Tellus A 64 (2012): 17516, doi:10.3402/tellusa.v64i0.17516.It is popular to use a horizontal explicit and a vertical implicit (HE-VI) scheme in the compressible nonhydrostatic (NH) model. However, when the aspect ratio becomes small, a small time-interval is required in HE-VI, because the Courant-Fredrich-Lewy (CFL) criterion is determined by the horizontal grid spacing. Furthermore, simulations from HE-VI can depart from the forward–backward (FB) scheme in NH even when the time interval is less than the CFL criterion allowed. Hence, a modified non-hydrostatic (MNH) model is proposed, in which the left-hand side of the continuity equation is multiplied by a parameter d (45d516, in this study). When the linearized MNH is solved by FB (can be other schemes), the eigenvalue shows that MNH can suppress the frequency of acoustic waves very effectively but does not have a significant impact on the gravity waves. Hence, MNH enables to use a longer time step than that allowed in the original NH. When the aspect ratio is small, MNH solved by FB can be more accurate and efficient than the NH solved by HE-VI. Therefore, MNH can be very useful to study cloud, Large Eddy Simulation (LES), turbulence, flow over complex terrains, etc., which require fine resolution in both horizontal and vertical directions

Variability of salivary analytes under daily conditions and their implications for periodontitis biomarkers

IntroductionRecent studies have identified inflammatory mediators as potential biomarkers for monitoring or diagnosing periodontitis. However, the brief half-life of these mediators, coupled with their variability among different individuals and across different stages of periodontal disease, may limit their reliability as biomarkers.MethodsIn this study, we assessed the concentration profile of salivary biomarkers (IL-6, IL-8, and total protein) through repeated measurements within the same day and across different days in 79 patients exhibiting various states of periodontal health: intact periodontium, stable periodontitis, and active periodontitis. Additionally, we explored how daily variations, such as the interval between toothbrushing and eating, impact the levels of these salivary biomarkers and their diagnostic efficacy for periodontitis activity.ResultsOur results showed high salivary levels of IL-6 and total proteins in periodontitis patients (p < 0.001), with detection ability reflected by an Area Under the Receiver Operating Characteristic Curve (AUC-ROC) ranging between 0.709 and 0.852. Conversely, IL-8 levels were higher in patients with intact periodontium (p < 0.001), with an AUC-ROC for periodontitis detection between 0.671 and 0.815. Daily activities such as toothbrushing and eating influenced the levels of specific analytes, particularly total proteins (p < 0.001), but this did not affect their ability to detect periodontal disease activity. The highest measurement agreement, assessed by Intraclass Correlation Coefficients (ICC), was found for IL-6, with no significant differences in agreement between same-day and different-day measurements.ConclusionsOur study demonstrated consistency in the repeated measurements of salivary analytes, both within the same day and across different days, except for salivary total protein levels. These analytes exhibited variability within a range that did not undermine their effectiveness as biomarkers for periodontal disease

Aerosol effects on liquid‐water path of thin stratocumulus clouds

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/94938/1/jgrd14994.pd

Coastally Trapped Wind Reversals: Progress toward Understanding

Coastally trapped wind reversals along the U.S. west coast, which are often accompanied by a northward surge of fog or stratus, are an important warm-season forecast problem due to their impact on coastal maritime activities and airport operations. Previous studies identified several possible dynamic mechanisms that could be responsible for producing these events, yet observational and modeling limitations at the time left these competing interpretations open for debate. In an effort to improve our physical understanding, and ultimately the prediction, of these events, the Office of Naval Research sponsored an Accelerated Research Initiative in Coastal Meteorology during the years 1993-98 to study these and other related coastal meteorological phenomena. This effort included two field programs to study coastally trapped disturbances as well as numerous modeling studies to explore key dynamic mechanisms. This paper describes the various efforts that occurred under this program to provide an advancement in our understanding of these disturbances. While not all issues have been solved, the synoptic and mesoscale aspects of these events are considerably better understood

Gout. Epidemiology of gout

Gout is the most prevalent form of inflammatory arthropathy. Several studies suggest that its prevalence and incidence have risen in recent decades. Numerous risk factors for the development of gout have been established, including hyperuricaemia, genetic factors, dietary factors, alcohol consumption, metabolic syndrome, hypertension, obesity, diuretic use and chronic renal disease. Osteoarthritis predisposes to local crystal deposition. Gout appears to be an independent risk factor for all-cause mortality and cardiovascular mortality and morbidity, additional to the risk conferred by its association with traditional cardiovascular risk factors

The influence of learning styles on knowledge acquisition in public sector management

This research note outlines a project designed to investigate the role of training institutions in providing effective training and development programmes for managers. The investigation is being carried out in the light of recent criticisms levelled against the nature of formal learning environments prevalent in most institutional settings. The traditional role of trainers and developers as the providers of knowledge and skills for the development of competent managers runs contrary to recent findings, which suggest that managers learn more effectively in informal settings, rather than the formal settings evident in many development programmes. The idea that explicitly extracted competencies are the target every manager should aim for to improve their effectiveness is also challenged because competencies alone are no longer regarded as a sufficient criterion for success. Recent research has attached greater importance to the need for helping managers to see knowledge as a social phenomenon, and one factor that might distinguish successful managers from others is tacit knowledge (Wagner & Sternberg, 1987; Argyris, 1999). A major focus of this study is to explore the possibility that the level and content of tacit knowledge acquired by managers may be influenced by their individual learning styles, and the degree to which their dominant styles are matched with the context of their work environment