6,510 research outputs found
Patient-Relativity and the Efficacy of Epicurean Therapy
According to Epicurus, philosophyâs sole task is to ensure the well-being of the soul. Human souls are often riddled with diseases; the most serious are the fear of the gods and the fear of death. Thus, the Epicureans offered several arguments designed to demonstrate that, for instance, âdeath is nothing to us,â and should therefore not be feared. Since their creation there has been much discussion, both in antiquity and by contemporary philosophers, about these arguments. In this thesis, I argue that Epicurean philosophical arguments are patient-relative; they necessarily adapt themselves so as to be therapeutically effective for their intended audience. The end result is that when we evaluate Epicurean philosophical arguments, we must do so in light of the audience for whom they were intended
Heaping and its Consequences for Duration Analysis
This paper analyses the consequences of heaping in duration models. Heaping is a specific form of response error typical to retrospectively collected labor force status data. Respondents round-off the spell length, when duration data is collected by episode-based questionnaires. Calendar-based questionnaires instead may lead to abnormal concentrations of the start and/or end of spells at specific calendar months. The investigation concentrates on this latter type of heaping, which Kraus and Steiner [1995] identified for the unemployment spell data from the German Socio-Economic Panel (GSOEP). In the special case of an exponential model heaping with a symmetric zero-mean measurement error does not bias the parameter estimate. In the Weibull model with duration dependence, however, it is proven that even such a symmetric heaping would lead to inconsistent estimation. We discuss the bias for general heaping patterns and derive from this a proposal for bias correction. In a number of simulation studies we check the theoretical results. The Monte Carlo simulations also show that an amount of heaping, that characterizes the GSOEP-West does not lead to considerably biased parameter estimates of a Weibull model. However, it clearly leads to spurious seasonal effects. Finally, some directions of future work are indicated
Restriction on the energy and luminosity of e+e- storage rings due to beamstrahlung
The role of beamstrahlung in high-energy e+e- storage-ring colliders (SRCs)
is examined. Particle loss due to the emission of single energetic
beamstrahlung photons is shown to impose a fundamental limit on SRC
luminosities at energies 2E_0 >~ 140 GeV for head-on collisions and 2E_0 >~ 40
GeV for crab-waist collisions. With beamstrahlung taken into account, we
explore the viability of SRCs in the E_0=240-500 GeV range, which is of
interest in the precision study of the Higgs boson. At 2E_0=240 GeV, SRCs are
found to be competitive with linear colliders; however, at 2E_0=400-500 GeV,
the attainable SRC luminosity would be a factor 15-25 smaller than desired.Comment: Latex, 5 pages. v2 differs only by minor changes is abstract and
introduction, one reference is added. v3 corresponds to the paper published
in PR
Detecting small-scale spatial heterogeneity and temporal dynamics of soil organic carbon (SOC) stocks: a comparison between automatic chamber-derived C budgets and repeated soil inventories
Carbon (C) sequestration in soils plays a key role in the global C cycle. It is therefore crucial to adequately monitor dynamics in soil organic carbon (âSOC) stocks when aiming to reveal underlying processes and potential drivers. However, small-scale spatial (10-30 m) and temporal changes in SOC stocks, particularly pronounced on arable lands, are hard to assess. The main reasons for this are limitations of the well-established methods. On the one hand, repeated soil inventories, often used in long-term field trials, reveal spatial patterns and trends in âSOC but require a longer observation period and a sufficient number of repetitions. On the other hand, eddy covariance measurements of C fluxes towards a complete C budget of the soil-plant-atmosphere system may help to obtain temporal âSOC patterns but lack small-scale spatial resolution.
To overcome these limitations, this study presents a reliable method to detect both short-term temporal dynamics as well as small-scale spatial differences of ÎSOC using measurements of the net ecosystem carbon balance (NECB) as a proxy. To estimate the NECB, a combination of automatic chamber (AC) measurements of CO2 exchange and empirically modeled aboveground biomass development (NPPshoot) were used. To verify our method, results were compared with ÎSOC observed by soil resampling.
Soil resampling and AC measurements were performed from 2010 to 2014 at a colluvial depression located in the hummocky ground moraine landscape of NE Germany. The measurement site is characterized by a variable groundwater level (GWL) and pronounced small-scale spatial heterogeneity regarding SOC and nitrogen (Nt) stocks. Tendencies and magnitude of âSOC values derived by AC-measurements and repeated soil inventories corresponded well. The period of maximum plant growth was identified as being most important for the development of spatial differences in annual ÎSOC. Hence, we were able to confirm that AC-based C budgets are able to reveal small-scale spatial differences and short-term temporal dynamics of âSOC
Sets of Priors Reflecting Prior-Data Conflict and Agreement
In Bayesian statistics, the choice of prior distribution is often debatable,
especially if prior knowledge is limited or data are scarce. In imprecise
probability, sets of priors are used to accurately model and reflect prior
knowledge. This has the advantage that prior-data conflict sensitivity can be
modelled: Ranges of posterior inferences should be larger when prior and data
are in conflict. We propose a new method for generating prior sets which, in
addition to prior-data conflict sensitivity, allows to reflect strong
prior-data agreement by decreased posterior imprecision.Comment: 12 pages, 6 figures, In: Paulo Joao Carvalho et al. (eds.), IPMU
2016: Proceedings of the 16th International Conference on Information
Processing and Management of Uncertainty in Knowledge-Based Systems,
Eindhoven, The Netherland
Restoration of peatlands and greenhouse gas balances
In this chapter the impact of peatland restoration on greenhouse gas fluxes is discussed based on a literature review. Casestudies are presented covering different peatland types, different regions and different starting conditions
Measurement of the Blackbody Radiation Shift of the 133Cs Hyperfine Transition in an Atomic Fountain
We used a Cs atomic fountain frequency standard to measure the Stark shift on
the ground state hyperfine transiton frequency in cesium (9.2 GHz) due to the
electric field generated by the blackbody radiation. The measures relative
shift at 300 K is -1.43(11)e-14 and agrees with our theoretical evaluation
-1.49(07)e-14. This value differs from the currently accepted one
-1.69(04)e-14. The difference has a significant implication on the accuracy of
frequency standards, in clocks comparison, and in a variety of high precision
physics tests such as the time stability of fundamental constants.Comment: 4 pages, 2 figures, 2 table
Nitrogen mineralization and gaseous nitrogen losses from waterlogged and drained organic soils in a black alder (<i>Alnus glutinosa</i> (L.) Gaertn.) forest
Black alder (<i>Alnus glutinosa</i> (L.) Gaertn.) forests on peat soils
have been reported to be hotspots for high nitrous oxide (N<sub>2</sub>O) losses.
High emissions may be attributed to alternating water tables of peatlands and
to the incorporation of high amounts of easily decomposable nitrogen (N) into
the ecosystem by symbiotic dinitrogen (N<sub>2</sub>)-fixation of alder trees. Our
study addressed the question to what extent drainage enhances the emissions
of N<sub>2</sub>O from black alder forests and how N turnover processes and
physical factors influence the production of N<sub>2</sub>O and total
denitrification. The study was conducted in a drained black alder forest with
variable groundwater tables at a southern German fen peatland. Fluxes of
N<sub>2</sub>O were measured using the closed chamber method at two drained sites
(D-1 and D-2) and one undrained site (U). Inorganic N contents and net N
mineralization rates (NNM) were determined. Additionally a laboratory
incubation experiment was carried out to investigate greenhouse gas and
N<sub>2</sub> fluxes at different temperature and soil moisture conditions.
Significantly different inorganic N contents and NNM rates were observed,
which however did not result in significantly different N<sub>2</sub>O fluxes in the
field but did in the laboratory experiment. N<sub>2</sub>O fluxes measured were low
for all sites, with total annual emissions of 0.51 ± 0.07 (U),
0.97 ± 0.13 (D-1) and
0.93 ± 0.08 kg N<sub>2</sub>OâN ha<sup>â1</sup> yr<sup>−1</sup> (D-2). Only 37%
of the spatiotemporal variation in field N<sub>2</sub>O fluxes could be explained
by peat temperature and groundwater level, demonstrating the complex
interlinking of the controlling factors for N<sub>2</sub>O emissions. However,
temperature was one of the key variables of N<sub>2</sub>O fluxes in the incubation
experiment conducted. Increasing soil moisture content was found to enhance
total denitrification losses during the incubation experiment, whereas
N<sub>2</sub>O fluxes remained constant. At the undrained site, permanently high
groundwater level was found to prevent net nitrification, resulting in a
limitation of available nitrate (NO<sub>3</sub><sup>−</sup>) and negligible gaseous N
losses. N<sub>2</sub>O flux rates that were up to four times higher were measured
in the incubation experiment. They reveal the potential of high N<sub>2</sub>O
losses under changing soil physical conditions at the drained alder sites.
The high net nitrification rates observed and high NO<sub>3</sub><sup>−</sup> contents bear
the risk of considerable NO<sub>3</sub><sup>−</sup> leaching at the drained sites
Characterization of Low Temperature Soluble Polyaniline
Because the charging of polyaniline films occurs in the bulk of the material rather than exclusively at the polymer-electrolyte interface, the use of thick polymer films for battery applications is justifiable. Here, we present a method for producing soluble polyaniline which can be
cast to form free-standing films. Investigation by scanning electron microsopy (SEM) has shown that these films are significantly more compact than those made by standard electropolymerization
Soil and Phyllosphere Microorganisms of the Rapeseed (Brassica napus L.) Holobiont Involved in Chloromethane Emissions
Brassica napus, or rapeseed, is one major oilseed crop in Europe and Germany and is used for food, feed, and Biodiesel production. Chloromethane (CH3Cl) is the most abundant halogenated organic compound in the atmosphere and triggers the chlorine-mediated destruction of the ozone layer. Anthropogenic sources became negligible because of taken measures according to the Montreal Protocol (1987) and therefore natural sources such as plants became more relevant for the global chloromethane budget. The actual global budget is imbalanced through missing sinks, which may be activities of soil and phyllosphere microbiomes which together with the plant is considered as the holobiont. The amount of CH3Cl from crops has not been addressed and might even increase under stresses such as elevated soil salinization and temperature. We proved that B. napus (rapeseed) plants emit CH3Cl. Certain methylotrophs (microorganisms that utilize one-carbon compounds) degrade CH3Cl and can gain a selective advantage while colonizing plants. Moreover, methylotrophs thrive in the rhizosphere of grassland plants. The rapeseed associated microbiome likely harbours methylotrophs that degrade CH3Cl. Therefore, we addressed in this study the rapeseed holobiont to resolve its response to stressors such as salt and temperature in regard to CH3Cl emission. We addressed in our project the following objectives: (i) To measure CH3Cl emission rates from single B. napus holobionts under different NaCl and temperature stress levels in pot experiments, (ii) to assess the B. napus microbiome and its CH3Cl degradation ability through amplicon sequencing of bacterial 16S rRNA genes and functional gene markers. The summer cultivar MAKRO was used as a model organism. We identified methylotrophs that responded to salt and temperature stress conditions in the phyllo- and rhizosphere of rapeseed and correlated those to the observed net emission rates
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