510 research outputs found
Nonmarine Ostracoda as proxies in (geo-)archaeology: a review
Abstract Ostracods as bioindicators are extremely useful for reconstructing palaeoenvironment and palaeoclimate and can also indicate the provenance of sediments and materials, for example, in studies on ancient commercial networks. Ostracods are small crustaceans that live in almost all aquatic habitats, both natural and man-made. Due to their calcitic carapace, they have high fossilization potential, and their use in geoarchaeology has been steadily increasing during the last decades. Their small size needs mean that only small volumes of sediment samples are needed, and species-specific ecological tolerances and preferences allow detailed palaeoenvironmental reconstructions. Typical methods of their application are palaeoecological analyses of associations based on ecological information and taphonomy, morphometric variability and stable isotope and chemistry analyses of their shells. The present paper aims to present an overview of applications of non-marine ostracods in (geo-)archaeological research, recommending sampling and analytical techniques for addressing archaeological research questions on palaeoclimate, habitat and landscape changes, water availability and quality, land use and other anthropogenic impacts, the provenance of materials and commercial networks to promote the application of Ostracoda in geoarchaeology/environmental archaeology.1 Introduction 2 Applications 2.1 short history of ostracod‐based palaeoenvironmental reconstructions 2.2 Palaeoclimate and palaeoenvironmental studies on continental archaeological sites 2.2.1 General palaeoenvironment/landscape reconstructions 2.2.2 Salinity 2.2.3 Temperature 2.2.4 Radiocarbon dating 2.3 Landscape changes by human activity 2.4 Water use and water works 2.5 Provenance studies 3 Methods for sampling and lab analyses 4 Conclusion
Recognition and property in Hegel and the early Marx
The article attempts to show, first, that for Hegel the role of property is to enable persons both to objectify their freedom and to properly express their recognition of each other as free, and second, that the Marx of 1844 uses fundamentally similar ideas in his exposition of communist society. For him the role of ‘true property’ is to enable individuals both to objectify their essential human powers and their individuality, and to express their recognition of each other as fellow human beings with needs, or their ‘human recognition’. Marx further uses these ideas to condemn the society of private property and market exchange as characterised by ‘estranged’ forms of property and recognition. He therefore uses a structure of ideas which Hegel had used to justify the institutions of private property and market exchange in order to condemn those same institutions. It is concluded that Marx’s adoption from Hegel of the idea that property as the means of self-objectification and of expressed recognition, leaves his vision of communism open to the charge that in it, just as in market society, the relations between human beings are mediated by things
SMOKE for Europe – adaptation, modification and evaluation of a comprehensive emission model for Europe
The US EPA regional emission model SMOKE was adopted and modified to create temporally and spatially distributed emission for Europe and surrounding countries based on official reports and public domain data only. The aim is to develop a flexible model capable of creating consistent high resolution emission data for long-term runs of Chemical Transport Models (CTMs). This modified version of SMOKE, called SMOKE for EUROPE (SMOKE-EU) was successfully used to create hourly gridded emissions for the timespan 1970–2010. <br><br> In this paper the SMOKE-EU model and the underlying European datasets are introduced. Emission data created by SMOKE-EU for the year 2000 are evaluated by comparison to data of three different state-of-the-art emission models. SMOKE-EU produced a range of values comparable to the other three datasets. Further, concentrations of criteria pollutants calculated by the CTM CMAQ using the four different emission datasets were compared against EMEP measurements with hourly and daily resolution. Using SMOKE-EU gave the most reliable modelling of O<sub>3</sub>, NO<sub>2</sub> and SO<sub>4</sub><sup>2&minus;</sup>. The amount of simulated concentrations within a factor of 2 (F2) of the observations for these species are: O<sub>3</sub> (F2 = 0.79, <i>N</i> = 329 197), NO<sub>2</sub> (F2 = 0.55, <i>N</i> = 11 465) and SO<sub>4</sub><sup>2&minus;</sup> (F2 = 0.62, <i>N</i> = 17 536). The lowest values were found for NH<sub>4</sub><sup>+</sup> (F2 = 0.34, <i>N</i> = 7400) and NO<sub>3</sub><sup>&minus;</sup> (F2 = 0.25, <i>N</i> = 6184). NH<sub>4</sub><sup>+</sup> concentrations were generally overestimated, leading to a fractional bias (FB) averaged over 22 measurement stations of (FB = 0.83 ± 0.41) while better agreements with observations were found for SO<sub>4</sub><sup>2&minus;</sup> (FB = 0.06 ± 0.38, 51 stations) and NO<sub>3</sub><sup>&minus;</sup> (FB = 0.13 &plusmn; 0.75, 18 stations). <br><br> CMAQ simulations using the three other emission datasets were similar to those modelled using SMOKE-EU emissions. Highest differences where found for NH<sub>4</sub><sup>+</sup> while O<sub>3</sub> concentrations were almost identical
Oedema of the metatarsal heads II-IV and forefoot pain as an unusual manifestation of Lyme disease: a case report
We report the case of a healthy 36 year old man who suffered from foot pain lasting for weeks, without having a specific medical history relating to it. The clinical evaluation was interpreted as a transfer metatarsalgia caused by a splayfoot. The radiographs revealed no pathology except the splayfoot deformity. Due to persistent pain and swelling of the entire forefoot, after two weeks of conventional treatment, magnet resonance images (MRI) and a blood sample were taken. The laboratory investigation showed raised levels of white blood cell count and C-reactive protein. The MRI showed up oedema in the metatarsal heads II-IV, as well as soft tissue swelling of the forefoot without any signs of decomposition
GEWEX Cloud System Study (GCSS) cirrus cloud working group: development of an observation-based case study for model evaluation
The GCSS working group on cirrus focuses on an inter-comparison of model simulations ranging from very detailed microphysical and dynamical models through to general circulation models (GCMs). The past GCSS cirrus cloud inter-comparison highlighted the wide range in modelling results that was a surprise to the modelling community. That inter-comparison was idealised and, therefore, a key issue was that it did not benefit from observations to help distinguish between model performances.
In this work, we aim to address this key issue by developing an observationally based case study to be used for the GCSS cirrus modelling inter-comparison study. We focused on developing a case that had sufficient observations with which to evaluate models, to help identify which models in the inter-comparison are performing well and highlight areas for model development. Furthermore, it will provide a base case for future model comparisons or testing of new or updated models. This paper outlines the modelling case development and the inter-comparison results will be presented in a follow-on paper.
The case was based on the 9 March 2000 Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) during an intensive observation period (IOP). The case was developed utilising various observations including ARM SGP remote sensing including the Milli-Meter Cloud Radar (MMCR), radiometers, radiosondes, aircraft observations, satellite observations, objective analysis and complemented with results from the Rapid Update Cycle (RUC) model as well as bespoke gravity wave simulations used to provide the best estimate for large scale forcing. The retrievals of ice water content, ice number concentration and fall velocity provide several constraints to evaluate model performances. Initial testing of the case has been reported using the UK Met Office Large Eddy Simulation Model (LEM) which suggests the case is appropriate for the model inter-comparison study. To our knowledge, this case offers the most detailed case study for cirrus comparison available and we anticipate this will offer significant benefits over past comparisons which have mostly been loosely based on observations
Identification of Lineage-Uncommitted, Long-Lived, Label-Retaining Cells in Healthy Human Esophagus and Stomach, and in Metaplastic Esophagus
Background & Aims
The existence of slowly cycling, adult stem cells has been challenged by the identification of actively cycling cells. We investigated the existence of uncommitted, slowly cycling cells by tracking 5-iodo-2'-deoxyuridine (IdU) label-retaining cells (LRCs) in normal esophagus, Barrett's esophagus (BE), esophageal dysplasia, adenocarcinoma, and healthy stomach tissues from patients.
Methods
Four patients (3 undergoing esophagectomy, 1 undergoing esophageal endoscopic mucosal resection for dysplasia and an esophagectomy for esophageal adenocarcinoma) received intravenous infusion of IdU (200 mg/m2 body surface area; maximum dose, 400 mg) over a 30-minute period; the IdU had a circulation half-life of 8 hours. Tissues were collected at 7, 11, 29, and 67 days after infusion, from regions of healthy esophagus, BE, dysplasia, adenocarcinoma, and healthy stomach; they were analyzed by in situ hybridization, flow cytometry, and immunohistochemical analyses.
Results
No LRCs were found in dysplasias or adenocarcinomas, but there were significant numbers of LRCs in the base of glands from BE tissue, in the papillae of the basal layer of the esophageal squamous epithelium, and in the neck/isthmus region of healthy stomach. These cells cycled slowly because IdU was retained for at least 67 days and co-labeling with Ki-67 was infrequent. In glands from BE tissues, most cells did not express defensin-5, Muc-2, or chromogranin A, indicating that they were not lineage committed. Some cells labeled for endocrine markers and IdU at 67 days; these cells represented a small population (<0.1%) of epithelial cells at this time point. The epithelial turnover time of the healthy esophageal mucosa was approximately 11 days (twice that of the intestine).
Conclusions
LRCs of human esophagus and stomach have many features of stem cells (long lived, slow cycling, uncommitted, and multipotent), and can be found in a recognized stem cell niche. Further analyses of these cells, in healthy and metaplastic epithelia, is required
Krt19\u3csup\u3e+\u3c/sup\u3e/Lgr5\u3csup\u3e-\u3c/sup\u3e Cells Are Radioresistant Cancer-Initiating Stem Cells in the Colon and Intestine
Epithelium of the colon and intestine are renewed every 3 days. In the intestine there are at least two principal stem cell pools. The first contains rapid cycling crypt-based columnar (CBC) Lgr5+ cells, and the second is composed of slower cycling Bmi1-expressing cells at the +4 position above the crypt base. In the colon, however, the identification of Lgr5- stem cell pools has proven more challenging. Here, we demonstrate that the intermediate filament keratin-19 (Krt19) marks long-lived, radiation-resistant cells above the crypt base that generate Lgr5+ CBCs in the colon and intestine. In colorectal cancer models, Krt19+ cancer-initiating cells are also radioresistant, while Lgr5+ stem cells are radiosensitive. Moreover, Lgr5+ stem cells are dispensable in both the normal and neoplastic colonic epithelium, as ablation of Lgr5+ stem cells results in their regeneration from Krt19-expressing cells. Thus, Krt19+ stem cells are a discrete target relevant for cancer therapy
The Top-Dog Index: A New Measurement for the Demand Consistency of the Size Distribution in Pre-Pack Orders for a Fashion Discounter with Many Small Branches
We propose the new Top-Dog-Index, a measure for the branch-dependent historic
deviation of the supply data of apparel sizes from the sales data of a fashion
discounter. A common approach is to estimate demand for sizes directly from the
sales data. This approach may yield information for the demand for sizes if
aggregated over all branches and products. However, as we will show in a
real-world business case, this direct approach is in general not capable to
provide information about each branch's individual demand for sizes: the supply
per branch is so small that either the number of sales is statistically too
small for a good estimate (early measurement) or there will be too much
unsatisfied demand neglected in the sales data (late measurement). Moreover, in
our real-world data we could not verify any of the demand distribution
assumptions suggested in the literature. Our approach cannot estimate the
demand for sizes directly. It can, however, individually measure for each
branch the scarcest and the amplest sizes, aggregated over all products. This
measurement can iteratively be used to adapt the size distributions in the
pre-pack orders for the future. A real-world blind study shows the potential of
this distribution free heuristic optimization approach: The gross yield
measured in percent of gross value was almost one percentage point higher in
the test-group branches than in the control-group branches.Comment: 22 pages, 15 figure
Bile acid and inflammation activate gastric cardia stem cells in a mouse model of barrett-like metaplasia
Esophageal adenocarcinoma (EAC) arises from Barrett esophagus (BE), intestinal-like columnar metaplasia linked to reflux esophagitis. In a transgenic mouse model of BE, esophageal overexpression of interleukin-1β phenocopies human pathology with evolution of esophagitis, Barrett-like metaplasia and EAC. Histopathology and gene signatures closely resembled human BE, with upregulation of TFF2, Bmp4, Cdx2, Notch1, and IL-6. The development of BE and EAC was accelerated by exposure to bile acids and/or nitrosamines, and inhibited by IL-6 deficiency. Lgr5+ gastric cardia stem cells present in BE were able to lineage trace the early BE lesion. Our data suggest that BE and EAC arise from gastric progenitors due to a tumor-promoting IL-1β-IL-6 signaling cascade and Dll1-dependent Notch signaling. © 2012 Elsevier Inc
Effects of ship emissions on air quality in the Baltic Sea region simulated with three different chemistry transport models
The Baltic Sea is a highly frequented shipping area with busy shipping lanes close to
densely populated regions. Exhaust emissions from ship traffic into the atmosphere
do not only enhance air pollution, they also affect the Baltic Sea environment
through acidification and eutrophication of marine waters and surrounding terrestrial
ecosystems. As part of the European BONUS project SHEBA (Sustainable Shipping and
Environment of the Baltic Sea region), the transport, chemical transformation and fate
of atmospheric pollutants in the Baltic Sea region were simulated with three regional
chemistry transport model (CTM) systems, CMAQ, EMEP/MSC-W and SILAM, with grid
resolutions between 4 and 11 km. The main goal was to quantify
the effect that shipping emissions have on the regional air quality in the Baltic Sea
region when the same shipping emission dataset but different CTMs are used in their typical
set-ups. The performance of these models and the shipping contribution to
the results of the individual models were evaluated for sulfur dioxide (SO2),
nitrogen dioxide (NO2), ozone (O3) and particulate matter
(PM2.5). Model results from the three CTMs for total air pollutant concentrations
were compared to observations
from rural and urban background stations of the AirBase monitoring network in the
coastal areas of the Baltic Sea region. Observed PM2.5
in summer was underestimated strongly by CMAQ and to some extent by EMEP/MSC-W.
Observed PM2.5 in winter was underestimated by SILAM.
In autumn all models were in better agreement with observed PM2.5.
The spatial average of the annual mean O3 in the EMEP/MSC-W simulation
was ca. 20 %
higher compared to the other two simulations, which is mainly the
consequence of using a different set of boundary conditions for the European model
domain. There are significant differences in the calculated ship contributions to the
levels of air pollutants among the three models.
EMEP/MSC-W, with the coarsest grid, predicted weaker ozone depletion through NO
emissions in the proximity of the main shipping routes than the other two models.
The average contribution of ships to PM2.5 levels in coastal land areas is
in the range of 3.1 %–5.7 % for the three CTMs.
Differences in ship-related PM2.5 between the models are mainly attributed
to differences in the schemes for inorganic aerosol formation.
Differences in the ship-related elemental carbon (EC) among the CTMs can be
explained by differences in the meteorological conditions, atmospheric transport
processes and the applied wet-scavenging parameterizations.
Overall, results from the
present study show the sensitivity of the ship contribution to combined uncertainties
in boundary conditions, meteorological data and aerosol formation and deposition schemes.
This is an important step towards a more reliable evaluation of policy options regarding emission
regulations for ship traffic and the planned introduction of a nitrogen emission control
area (NECA) in the Baltic Sea and the North Sea in 2021.</p
- …