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LITOS - A new balloon-borne instrument for fine-scale turbulence soundings in the stratosphere
We have developed a new compact balloon payload called LITOS (Leibniz-Institute Turbulence Observations in the Stratosphere) for high resolution wind turbulence soundings in the stratosphere up to 35 km altitude. The wind measurements are performed using a constant temperature anemometer (CTA) with a vertical resolution of ∼2.5 mm, i.e. 2 kHz sampling rate at 5 m/s ascent speed. Thereby, for the first time, it is possible to study the entire turbulence spectrum down to the viscous subrange in the stratosphere. Including telemetry, housekeeping, batteries and recovery unit, the payload weighs less than 5 kg and can be launched from any radiosonde station. Since autumn 2007, LITOS has been successfully launched several times from the Leibniz-Institute of Atmospheric Physics (IAP) in Kühlungsborn, Germany (54° N, 12° E). Two additional soundings were carried out in 2008 and 2009 in Kiruna, Sweden (67° N, 21° E) as part of the BEXUS program (Balloon-borne EXperiments for University Students). We describe here the basic principle of CTA measurements and prove the validity of this method in the stratosphere. A first case study allows a clear distinction between non-turbulent regions and a turbulent layer with a thickness of some tens of meters. Since our measurements cover the transition between the inertial and viscous subrange, energy dissipation rates can be calculated with high reliability
Holocene forest and land-use history of the Erzgebirge, central Europe: a review of palynological data
The ongoing ecological conversion of mountain forests in central Europe from
widespread Picea monocultures to mixed stands conceptually also requires a
historical perspective on the very long-term, i.e. Holocene, vegetation and
land-use dynamics. Detailed sources of information for this are
palynological data. The Erzgebirge in focus here, with a maximum
height of 1244 m a.s.l., represents an extreme case of extensive historical
deforestation since the Middle Ages due to mining, metallurgy, and other
industrial activities, as well as rural and urban colonisation. For this
regional review we collected and evaluated 121 pollen diagrams of different
stratigraphic, taxonomic, and chronological resolution. This number makes
this region an upland area in central Europe with an exceptionally high
density of palynological data. Using well-dated diagrams going back to the
early Holocene, main regional vegetation phases were derived: the Betula–Pinus phase (ca.
11 600–10 200 cal yr BP), the Corylus phase (ca. 10 200–9000 cal yr BP), the Picea phase
(ca. 9000–6000 cal yr BP), the Fagus–Picea phase (ca. 6000–4500 cal yr BP), the
Abies–Fagus–Picea phase (ca. 4000–1000 cal yr BP), and the anthropogenic vegetation phase (ca.
1000–0 cal yr BP). Some diagrams show the presence or even continuous curves
of potential pasture and meadow indicators from around 2000 cal BCE at the
earliest. Even cereal pollen grains occur sporadically already before the
High Medieval. These palynological indications of a local prehistoric human
impact also in the higher altitudes find parallels in the
(geo-)archaeologically proven Bronze Age tin placer mining and in the
geochemically proven Iron Age metallurgy in the Erzgebirge. The pollen data
show that immediately before the medieval clearing, i.e. beginning at the
end of the 12th century CE, forests were mainly dominated by Fagus and Abies and
complemented by Picea with increasing share towards the highest altitudes.
According to historical data, the minimum of the regional forest cover was
reached during the 17th–18th centuries CE. The dominance of Picea in modern
pollen spectra is caused by anthropogenic afforestation in the form of
monocultures since that time. Future palynological investigations,
preferably within the framework of altitudinal transect studies, should aim
for chronologically and taxonomically high-resolution and radiometrically
well-dated pollen diagrams from the larger peatlands.</p
Case report: Perioperative management of a patient with shapiro syndrome during on-pump cardiac surgery
Psychometric Evaluation of the German Version of the Demoralization Scale-II and the Association Between Demoralization, Sociodemographic, Disease- and Treatment-Related Factors in Patients With Cancer
Objective: To test the psychometric properties, internal consistency, dimensional
structure, and convergent validity of the German version of the Demoralization Scale-
II (DS-II), and to examine the association between demoralization, sociodemographic,
disease- and treatment-related variables in patients with cancer.
Methods: We recruited adult patients with cancer at a Psychosocial Counseling Center
and at oncological wards. Participants completed the 16-item DS-II, Patient Health
Questionnaire-9 (PHQ-9), Generalized Anxiety Disorder Screener-2 (GAD-2), Distress
Thermometer (DT), and Body Image Scale (BIS). We analyzed internal consistency
of the DS-II using Cronbach‘s Alpha (a). We tested the dimensional structure of the
DS-II with Confirmatory Factor Analyses (CFA). Convergent validity was expressed
through correlation coefficients with established measures of psychological distress.
The associations between demoralization, sociodemographic, disease- and treatmentrelated
variables were examined with ANOVAs.
Results: Out of 942 eligible patients, 620 participated. The average DS-II total score
was M = 5.78, SD = 6.34, the Meaning and Purpose subscale M = 2.20, SD = 3.20,
and the Distress and Coping Ability subscale M = 3.58, SD = 3.45. Internal consistency
ranged from high to excellent with a = 0.93 for the DS-II total scale, a = 0.90 for
the Meaning and Purpose subscale, and a = 0.87 for the Distress and Coping Ability
subscale. The one-factor and the two-factor model yielded similar model fits, with
CFI and TLI ranging between 0.910 and 0.933, SRMR < 0.05. The DS-II correlated
significantly with depression (PHQ-9: r = 0.69), anxiety (GAD-2: r = 0.72), mental distress
(DT: r = 0.36), and body image disturbance (BIS: r = 0.58). High levels of demoralization
were reported by patients aged between 18 and 49 years (M = 7.77, SD = 6.26), patients
who were divorced/separated (M = 7.64, SD = 7.29), lung cancer patients (M = 9.29,
SD = 8.20), and those receiving no radiotherapy (M = 7.46, SD = 6.60).
Conclusion: The DS-II has very good psychometric properties and can be
recommended as a reliable tool for assessing demoralization in patients with cancer.
The results support the implementation of a screening for demoralization in specific risk
groups due to significantly increased demoralization scores
Non-chaotic dynamics in general-relativistic and scalar-tensor cosmology
In the context of scalar-tensor models of dark energy and inflation, the
dynamics of vacuum scalar-tensor cosmology are analysed without specifying the
coupling function or the scalar field potential. A conformal transformation to
the Einstein frame is used and the dynamics of general relativity with a
minimally coupled scalar field are derived for a generic potential. It is shown
that the dynamics are non-chaotic, thus settling an existing debate.Comment: 20 pages, LaTeX, to appear in Class. Quantum Gra
Restoring shellfish reefs: Global guidelines for practitioners and scientists
Widespread global declines in shellfish reefs (ecosystem-forming bivalves such as oysters and mussels) have led to growing interest in their restoration and protection. With restoration projects now occurring on four continents and in at least seven countries, global restoration guidelines for these ecosystems have been developed based on experience over the past two decades. The following key elements of the guidelines are outlined: (a) the case for shellfish reef resto- ration and securing financial resources; (b) planning, feasibility, and goal set- ting; (c) biosecurity and permitting; (d) restoration in practice; (e) scaling up from pilot to larger scale restoration, (f) monitoring, (g) restoration beyond oyster reefs (specifically mussels), and (h) successful communication for shell- fish reef restoration projects
The role of beach state and the timing of pre-storm surveys in determining the accuracy of storm impact assessments
Dune erosion principally occurs when water level exceeds the elevation of the beach and predicting erosion is progressively becoming more important for management as coastal populations increase, sea level rises, and storms become more powerful. This study assesses storm impacts using a simple model from Stockdon et al. (2007) configured with oceanographic information from the ADCIRC + SWAN model and frequently collected beach profiles. We applied that model to barrier islands in North Carolina including: Core Banks with a more dissipative beach morphology and Shackleford Banks and Onslow Beach with intermediate beach morphologies. The study periods captured 10 events where wave collision with the dunes and/or overwash were either predicted or observed, including large multiple-day events caused by hurricanes and smaller events caused by onshore winds and high tide. Comparing model output with a time series of beach photographs shows the predictive power and sensitivity of the model was consistently high at the Core Banks Site with its wide and low-gradient beach, high-elevation dunes (2.58 m), and high resistance to overwash. Model predictive power and sensitivity was lowest at the Shackleford Banks Site because frequent and large changes to beach slope and intermediate dune elevation (0.54–1.25 m) caused small variations of modeled total water level to either overpredict or underpredict storm impacts. In addition, storm impacts were always overpredicted during hurricanes at the Shackleford Banks Site, which was likely due to storm waves decreasing the beach slope from what was measured prior to the event and used as model input. Like Shackleford Banks, the beach slope of the Onslow Beach Site was steep and variable, but the low-elevation dunes (0.24–0.28 m) made resistance to overwash low and the predictive power and sensitivity of the model higher than at the Shackleford Banks Site. Results suggest that storm impacts and the associated potential for dune erosion is predicted more accurately at beaches where the threshold for overwash is high or low because total water level during most events will commonly fall short of or exceed the overwash threshold, respectively. The accuracy of predicting the storm impact regime is sensitive to beach slope. The slope of intermediate beaches is more variable than dissipative beaches and requires frequent measurement if it is to be represented accurately in the model, but this can be impractical and costly even using the latest drone-surveying methods. To maximize the accuracy of predicting storm impacts, intermediate beach morphology should be constrained by surveying at seasonal or yearly time scales and used as input to numerical models that estimate beach slope over short time scales (hours during an event or daily), configured with the latest wave and water-level forecasts
Long-term land-cover/use change in a traditional farming landscape in Romania inferred from pollen data, historical maps and satellite images
Traditional farming landscapes in the temperate
zone that have persisted for millennia can be exceptionally species-rich and are therefore key conservation targets. In contrast to Europe’s West, Eastern Europe harbours widespread traditional farming landscapes, but drastic socio-economic and political changes in the twentieth century are likely to have impacted these landscapes profoundly. We reconstructed long-term land-use/cover and biodiversity changes over the last 150 years in a traditional farming landscape of outstanding species diversity in Transylvania. We used the Regional Estimates of Vegetation Abundance from Large Sites model applied to a pollen record from the Transylvanian Plain and a suite of historical and satellite-based maps. We documented widespread changes in the extent and location of grassland and cropland, a loss of wood pastures as well as a gradual increase in forest extent. Land management in the socialist period (1947–1989) led to grassland expansion, but grassland diversity decreased due to intensive production. Land-use intensity has declined since the collapse of socialism in 1989, resulting in widespread cropland abandonment and conversion to grassland. However, these trends may be
temporary due to both ongoing woody encroachment as
well as grassland management intensification in productive areas. Remarkably, only 8% of all grasslands existed throughout the entire time period (1860–2010), highlighting the importance of land-use history when identifying target areas for conservation, given that old-growth grasslands are most valuable in terms of biodiversity. Combining datasets from different disciplines can yield important additional insights into dynamic landscape and biodiversity changes, informing conservation actions to maintain these species-rich landscapes in the longer term
CD105 is a prognostic marker and valid endothelial target for microbubble platforms in cholangiocarcinoma
Purpose
The current treatment outcomes in cholangiocarcinoma are poor with cure afforded only by surgical extirpation. The efficacy of targeting the tumoural endothelial marker CD105 in cholangiocarcinoma, as a basis for potential microbubble-based treatment, is unknown and was explored here.
Methods
Tissue expression of CD105 was quantified using immunohistochemistry in 54 perihilar cholangiocarcinoma samples from patients who underwent resection in a single centre over a ten-year period, and analysed against clinicopathological data. In vitro flow assays using microbubbles functionalised with CD105 antibody were conducted to ascertain specificity of binding to murine SVR endothelial cells. Finally, CD105-microbubbles were intravenously administered to 10 Balb/c nude mice bearing heterotopic subcutaneous human extrahepatic cholangiocarcinoma (TFK-1 and EGI-1) xenografts after which in vivo binding was assessed following contrast-enhanced destruction replenishment ultrasound application.
Results
Though not significantly associated with any examined clinicopathological variable, we found that higher CD105 expression was independently associated with poorer patient survival (median 12 vs 31 months; p = 0.002). In vitro studies revealed significant binding of CD105-microbubbles to SVR endothelial cells in comparison to isotype control (p = 0.01), as well as in vivo to TFK-1 (p = 0.02) and EGI-1 (p = 0.04) mouse xenograft vasculature.
Conclusion
Our results indicate that CD105 is a biomarker eminently suitable for cholangiocarcinoma targeting using functionalised microbubbles
Identification of polymorphic microsatellite loci for the endangered Kagu (Rhynochetos jubatus) by high-throughput sequencing
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