On the Structure of the Lower Troposphere in the Summertime Stratocumulus Regime of the Northeast Pacific

Data collected in situ as part of the second field study of the Dynamics and Chemistry of Marine Stratocumulus field program are used to evaluate the state of the atmosphere in the region of field operations near 30°N, 120°W during July 2001, as well as its representation by a variety of routinely available data. The routine data include both the 40-yr European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis (ERA-40) and NCEP–NCAR reanalyses, forecasts from their respective forecast systems (the Integrated and Global Forecast Systems), the 30-km archive from the International Satellite Cloud Climatology Project (ISCCP), the Quick Scatterometer surface winds, and remotely sensed fields derived from radiances measured by the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI), the Advanced Microwave Sounding Unit, and the Advanced Very High Resolution Radiometer. The analysis shows that outside of the boundary layer the state of the lower troposphere is reasonably represented by the reanalysis and forecast products, with the caveat of a slight warm bias at 850 hPa in the NCEP–NCAR products. Within the planetary boundary layer (PBL) the agreement is not as good: both the boundary layer depth and cloud amount are underpredicted, and the boundary layer temperature correlates poorly with the available data, which may be related to a poor representation of SSTs in this region of persistent cloud cover. ERA-40 also suffers from persistently weak zonal winds within the PBL. Among the satellite records the ISCCP data are found to be especially valuable, evincing skill in both predicting boundary layer depth (from cloud-top temperatures and TMI surface temperatures) and cloud liquid water paths (from cloud optical depths). An analysis of interannual variability (among Julys) based on ERA-40 and the 1983–2001 ISCCP record suggests that thermodynamic quantities show similar interannual and synoptic variability, principally concentrated just above the PBL, while dynamic quantities vary much more on synoptic time scales. Furthermore, the analysis suggests that the correlation between stratocumulus cloud amount and lower-tropospheric stability exhibits considerable spatial structure and is less pronounced than previously thought

Heimerziehung damals und heute - Eine Studie zu Veränderungen und Auswirkungen der Heimerziehung über die letzten 40 Jahre!

Heimerziehung bedeutet, dass Kinder und Jugendliche mit einer defizitären Sozialisation an einem anderen Ort als in der Ursprungsfamilie erzogen werden. Diese Erziehung geschieht aus organisatorischen und pädagogischen Gründen meist in einem professionellen Kontext. In der folgenden Studie geht es um diesen professionellen Kontext, nämlich um Heimerziehung. Im Focus stehen dabei zwei ausgewählte Einrichtungen der Kinder- und Jugendhilfe. Einmal das Rheinische Landesjugendheim Viersen-Süchteln, das 1972 auf die Forderungen der Heimkampagne reagierte und die politisch und pädagogisch überfälligen Veränderungen durch eine Umstrukturierung im demokratischen Sinne vollzog. Und zum anderen das Heilpädagogisch-Psychotherapeutische Zentrum Die Gute Hand in Kürten-Biesfeld. Diese Einrichtung wirde vorgestellt um aufzuzeigen, mit welchen Themen eine Einrichtung der Kinder- und Jugendhilfe heute konfrontiert wird. Die leitende Frage bei den Betrachtungen beiden Einrichtungen lautet: Welche Auswirkungen sind im mikrokosmischen Bereich aufgrund der verschiedenen Einflüsse des Makro- und Mesokosmos zu beobachten, und wie hat sie die inhaltliche und organisatorische Struktur eines Kinderheims heute im Vergleich zu damals verändert? Dafür wird zunächst ein Blick auf den gesellschaftspolitischen Kontext der 60er Jahre und auf den der Gegenwart geworfen. Anschließend werden die Einflüsse einer mesokosmischen Ebene verdeutlicht: einerseits die Heimkampagne mit ihren Forderungen in den 60er Jahren und andererseits das Kinder- und Jugendhilfegesetzes (KJHG) als juristische Grundlage und Voraussetzung für eine gelingende Heimerziehung in den 90er Jahren. Danach werden die beiden Einrichtungen selbst vorgestellt, bevor die Innovationen am Ende der jeweiligen Kapitel wiederum in einem größeren Zusammenhang reflektiert werden, so dass ein Überblick über die Themen der Kinder- und Jugendhilfe in den Jahren 1969 bis 2007 (also knapp 40 Jahre Fremdunterbringung) während und nach der Heimkampagne wie auch der Gegenwart deutlich wird. Im Fazit veranschauliche ich die Konsequenzen der Entwicklungen damals und heute für das zukünftige Szenario der Kinder- und Jugendhilfe und leite aus den vorangegenagenen Ebenen Empfehlungen für eine Weiterentwicklung ab

Sr2+/Ca2+ and 44Ca/40Ca fractionation during inorganic calcite formation: III. Impact of salinity/ionic strength

In order to apply Sr/Ca and 44Ca/40Ca fractionation during calcium carbonate (CaCO3) formation as a proxy to reconstruct paleo-environments, it is essential to evaluate the impact of various environmental factors. In this study, a CO2 diffusion technique was used to crystallize inorganic calcite from aqueous solutions at different ionic strength/salinity by the addition of NaCl at 25 °C. Results show that the discrimination of Sr2+ versus Ca2+ during calcite formation is mainly controlled by precipitation rate (R in μmol/m2/h) and is weakly influenced by ionic strength/salinity. In analogy to Sr incorporation, 44Ca/40Ca fractionation during precipitation of calcite is weakly influenced by ionic strength/salinity too. At 25 °C the calcium isotope fractionation between calcite and aqueous calcium ions (Δ44/40Cacalcite-aq = δ44/40Cacalcite − δ44/40Caaq) correlates inversely to log R values for all experiments. In addition, an inverse relationship between Δ44/40Cacalcite-aq and log DSr, which is independent of temperature, precipitation rate, and aqueous (Sr/Ca)aq ratio, is not affected by ionic strength/salinity either. Considering the log DSr and Δ44/40Cacalcite-aq relationship, Sr/Ca and δ44/40Cacalcite values of precipitated calcite can be used as an excellent multi-proxy approach to reconstruct environmental conditions (e.g., temperature, precipitation rate) of calcite growth and diagenetic alteration

Tailoring THz radiation by controlling tunnel photoionization events in gases

Applications ranging from nonlinear terahertz spectroscopy to remote sensing require broadband and intense THz radiation which can be generated by focusing two-color laser pulses into a gas. In this setup, THz radiation originates from the buildup of the electron density in sharp steps of attosecond duration due to tunnel ionization, and subsequent acceleration of free electrons in the laser field. We show that the spectral shape of the THz pulses generated by this mechanism is determined by superposition of contributions from individual ionization events. This provides a straightforward analogy with linear diffraction theory, where the ionization events play the role of slits in a grating. This analogy offers simple explanations for recent experimental observations and opens new avenues for THz pulse shaping based on temporal control of the ionization events. We illustrate this novel technique by tailoring the spectral width and position of the resulting radiation using multi-color pump pulses

Structural mechanism for the recognition and ubiquitination of a single nucleosome residue by Rad6-Bre1

Cotranscriptional ubiquitination of histone H2B is key to gene regulation. The yeast E3 ubiquitin ligase Bre1 (human RNF20/40) pairs with the E2 ubiquitin conjugating enzyme Rad6 to monoubiquitinate H2B at Lys123. How this single lysine residue on the nucleosome core particle (NCP) is targeted by the Rad6-Bre1 machinery is unknown. Using chemical cross-linking and mass spectrometry, we identified the functional interfaces of Rad6, Bre1, and NCPs in a defined in vitro system. The Bre1 RING domain cross-links exclusively with distinct regions of histone H2B and H2A, indicating a spatial alignment of Bre1 with the NCP acidic patch. By docking onto the NCP surface in this distinct orientation, Bre1 positions the Rad6 active site directly over H2B Lys123. The Spt-Ada-Gcn5 acetyltransferase (SAGA) H2B deubiquitinase module competes with Bre1 for binding to the NCP acidic patch, indicating regulatory control. Our study reveals a mechanism that ensures site-specific NCP ubiquitination and fine-tuning of opposing enzymatic activities

A novel model to estimate lymph node metastasis in endometrial cancer patients

OBJECTIVES: To evaluate the postoperative pathological characteristics of hysterectomy specimens, preoperative cancer antigen (CA)-125 levels and imaging modalities in patients with endometrial cancer and to build a risk matrix model to identify and recruit patients for retroperitoneal lymphadenectomy. METHODS: A total of 405 patients undergoing surgical treatment for endometrial cancer were retrospectively reviewed and analyzed. Clinical (age and body mass index), laboratory (CA-125), radiological (lymph node evaluation), and pathological (tumour size, grade, lymphovascular space invasion, lymph node metastasis, and myometrial invasion) parameters were used to test the ability to predict lymph node metastasis. Four parameters were selected by logistic regression to create a risk matrix for nodal metastasis. RESULTS: Of the 405 patients, 236 (58.3%) underwent complete pelvic and para-aortic lymphadenectomy, 96 (23.7%) underwent nodal sampling, and 73 (18%) had no surgical lymph node assessment. The parameters predicting nodal involvement obtained through logistic regression were myometrial infiltration >;50%, lymphovascular space involvement, pelvic lymph node involvement by imaging, and a CA-125 value >;21.5 U/mL. According to our risk matrix, the absence of these four parameters implied a risk of lymph node metastasis of 2.7%, whereas in the presence of all four parameters the risk was 82.3%. CONCLUSION: Patients without deep myometrial invasion and lymphovascular space involvement on the final pathological examination and with normal CA-125 values and lymph node radiological examinations have a relatively low risk of lymph node involvement. This risk assessment matrix may be able to refer patients with high-risk parameters necessitating lymphadenectomy and to decide the risks and benefits of lymphadenectomy

Human bone marrow contains high levels of extracellular vesicles with a tissue-specific subtype distribution

Introduction Extracellular vesicles (EV) are shed from a broad variety of cells and play an important role in activation of coagulation, cell to cell interaction and transport of membrane components. They are usually measured as circulating EV in peripheral blood (PB) and other body fluids. However, little is known about the distribution, presence and impact of EV and their sub-populations in bone marrow (BM). In our study, we focused on the analysis of different EV subtypes in human BM as compared to EV subsets in PB. Methods EV in BM and PB from 12 healthy stem cell donors were measured by flow-cytometry using Annexin V and cell-specific antibodies for hematopoietic stem cells, leucocytes, platelets, red blood cells, and endothelial cells. Additionally, concentrations of tissue factor-bearing EV were evaluated. Results High numbers of total EV were present in BM (median value [25-75 percentile]: 14.8 x10(9)/l [8.5-19.3]). Non-significantly lower numbers of total EV were measured in PB (9.2 x10(9)/l [3.8-14.5]). However, distribuation of EV subtypes showed substantial differences between BM and PB: In PB, distribution of EV fractions was similar as previously described. Most EV originated from platelets (93.9%), and only few EV were derived from leucocytes (4.5%), erythrocytes (1.8%), endothelial cells (1.0%), and hematopoietic stem cells (0.7%). In contrast, major fractions of BM-EV were derived from red blood cells or erythropoietic cells (43.2%), followed by megacaryocytes I platelets (27.6%), and by leucocytes as well as their progenitor cells (25,7%);only low EV proportions originated from endothelial cells and hematopoietic stem cells (2.0% and 1.5%, respectively). Similar fractions of tissue factor- bearing EV were found in BM and PB (1.3% and 0.9%). Conculsion Taken together, we describe EV numbers and their subtype distribution in the BM compartment for the first time. The tissue specific EV distribution reflects BM cell composition and favours the idea of a BM-PB barrier existing not only for cells, but also for EV