4,549 research outputs found
Ökologischer Kreislauf Moorbad Harbach: Life Cycle Assessment (LCA) for Agricultural Plant Production and Transportation
In 1992 the community of Moorbad Harbach (Austria), located near the border of the Czech Republic and dominated by extensive agricultural practice on small scale farms, decided to initiate activities for regional devolopment. About 40 farms (27 %) converted to organic farming, a local marketing service as well as regional food processing businesses (slaughterhouse, dairy), operating as linkages between regional agriculture and the local spa hotel were founded. The basic idea for the work presented here was to evaluate the – especially ecological – consequences of such a regional conversion. One part of this attempt of evaluation was carried out as a LCA for the agricultural production in Moorbad Harbach. The emphasis of the study was to compare plant production before and after the regional conversion to organic farming. In another step changes in transportation distances and quantities with special regard to transport of raw milk and milk products were quantified
The ethical challenge of Touraine's 'living together'
In Can We Live Together? Alain Touraine combines a consummate analysis of crucial social tensions in contemporary societies with a strong normative appeal for a new emancipatory 'Subject' capable of overcoming the twin threats of atomisation or authoritarianism. He calls for a move from 'politics to ethics' and then from ethics back to politics to enable the new Subject to make a reality out of the goals of democracy and solidarity. However, he has little to say about the nature of such an ethics. This article argues that this lacuna could usefully be filled by adopting a form of radical humanism found in the work of Erich Fromm. It defies convention in the social sciences by operating from an explicit view of the 'is' and the 'ought' of common human nature, specifying reason, love and productive work as the qualities to be realised if we are to move closer to human solidarity. Although there remain significant philosophical and political differences between the two positions, particularly on the role to be played by 'the nation', their juxtaposition opens new lines of inquiry in the field of cosmopolitan ethics
Benthic Macrofauna of the New York Bight, 1979-89
The benthic macrofauna of the New York Bight has been monitored extensively, primarily to determine trends over space and time in biological effects of waste inputs. In
the present study, from 44 to 48 stations were sampled each summer from 1980-1985. Data from other Bight benthic studies are included to· extend the temporal coverage
from 1979 to 1989. Numbers of species and amphipods per sample, taken as relatively sensitive indicators of environmental stress, showed consistent spatial patterns. Lowest values were found in the Christiaensen Basin and other inshore areas, and numbers increased toward the outermost shelf and Hudson Shelf Valley stations. There were
statistically significant decreases in species and amphipods at most stations from 1980 to 1985. (Preliminary data from a more recent study suggest numbers of species increased again between 1986 and 1989.) Cluster analysis of 1980-85 data indicated several distinct assemblages-sewage sludge dumpsite, sludge accumulation area, inner Shelf Valley, outer Shelf Valley, outer shelf-with little change over time. The "enriched" and "highly altered" assemblages in the Basin appear similar to those reported since sampling began there in 1968. No consistently defaunated areas have been found in any sampling programs over the past 20 years. On a gross level, therefore, recent faunal responses to any environmental changes are not evident, but the more sensitive measures used, i.e. numbers of species and amphipods, do indicate widespread recent effects. Causes of the faunal changes are not obvious; some possibilities, including increasing effects of sewage
sludge or other waste inputs, natural factors, and sampling artifacts, are discussed. (PDF file contains 54 pages.
Conflict in the Indian Kashmir Valley I: exposure to violence.
ABSTRACT: BACKGROUND: India and Pakistan have disputed ownership of the Kashmir Valley region for many years, resulting in several conflicts since the end of partition in 1947. Very little is known about the prevalence of violence and insecurity in this population. METHODS: We undertook a two-stage cluster household survey in two districts (30 villages) of the Indian part of Kashmir to assess experiences with violence and mental health status among the conflict-affected Kashmiri population. The article presents our findings for confrontations with violence. Data were collected for recent events (last 3 months) and those occurring since the start of the conflict. Informed consent was obtained for all interviews. RESULTS: 510 interviews were completed. Respondents reported frequent direct confrontations with violence since the start of conflict, including exposure to crossfire (85.7%), round up raids (82.7%), the witnessing of torture (66.9%), rape (13.3%), and self-experience of forced labour (33.7%), arrests/kidnapping (16.9%), torture (12.9%), and sexual violence (11.6%). Males reported more confrontations with violence than females, and had an increased likelihood of having directly experienced physical/mental maltreatment (OR 3.9, CI: 2.7-5.7), violation of their modesty (OR 3.6, CI: 1.9-6.8) and injury (OR 3.5, CI: 1.4-8.7). Males also had high odds of self-being arrested/kidnapped (OR 8.0, CI: 4.1-15.5). CONCLUSION: The civilian population in Kashmir is exposed to high levels of violence, as demonstrated by the high frequency of deliberate events as detention, hostage, and torture. The reported violence may result in substantial health, including mental health problems. Males reported significantly more confrontations with almost all violent events; this can be explained by higher participation in outdoor activities
Long spin relaxation times in wafer scale epitaxial graphene on SiC(0001)
We developed an easy, upscalable process to prepare lateral spin-valve
devices on epitaxially grown monolayer graphene on SiC(0001) and perform
nonlocal spin transport measurements. We observe the longest spin relaxation
times tau_S in monolayer graphene, while the spin diffusion coefficient D_S is
strongly reduced compared to typical results on exfoliated graphene. The
increase of tau_S is probably related to the changed substrate, while the cause
for the small value of D_S remains an open question.Comment: 16 pages, 3 figures, 1 tabl
The quasi-free-standing nature of graphene on H-saturated SiC(0001)
We report on an investigation of quasi-free-standing graphene on 6H-SiC(0001)
which was prepared by intercalation of hydrogen under the buffer layer. Using
infrared absorption spectroscopy we prove that the SiC(0001) surface is
saturated with hydrogen. Raman spectra demonstrate the conversion of the buffer
layer into graphene which exhibits a slight tensile strain and short range
defects. The layers are hole doped (p = 5.0-6.5 x 10^12 cm^(-2)) with a carrier
mobility of 3,100 cm^2/Vs at room temperature. Compared to graphene on the
buffer layer a strongly reduced temperature dependence of the mobility is
observed for graphene on H-terminated SiC(0001)which justifies the term
"quasi-free-standing".Comment: 3 pages, 3 figures, accepted for publication in Applied Physics
Letter
Localized states influence spin transport in epitaxial graphene
We developed a spin transport model for a diffusive channel with coupled
localized states that result in an effective increase of spin precession
frequencies and a reduction of spin relaxation times in the system. We apply
this model to Hanle spin precession measurements obtained on monolayer
epitaxial graphene on SiC(0001) (MLEG). Combined with newly performed
measurements on quasi-free-standing monolayer epitaxial graphene on SiC(0001)
our analysis shows that the different values for the diffusion coefficient
measured in charge and spin transport measurements in MLEG and the high values
for the spin relaxation time can be explained by the influence of localized
states arising from the buffer layer at the interface between the graphene and
the SiC surface.Comment: 6 pages, 3 figures, including supplementary materia
Fabry-Perot enhanced Faraday rotation in graphene
We demonstrate that giant Faraday rotation in graphene in the terahertz range
due to the cyclotron resonance is further increased by constructive Fabry-Perot
interference in the supporting substrate. Simultaneously, an enhanced total
transmission is achieved, making this effect doubly advantageous for
graphene-based magneto-optical applications. As an example, we present
far-infrared spectra of epitaxial multilayer graphene grown on the C-face of
6H-SiC, where the interference fringes are spectrally resolved and a Faraday
rotation up to 0.15 radians (9{\deg}) is attained. Further, we discuss and
compare other ways to increase the Faraday rotation using the principle of an
optical cavity
Accounting students' expectations and transition experiences of supervised work experience
Political and economic discourses position employability as a responsibility of higher education, which utilise mechanisms such as supervised work experience (SWE) to embed employability into the undergraduate curriculum. However, sparse investigation of students' contextualised experiences of SWE results in little being known about the mechanisms through which students derive employability benefits from SWE. The aim of this study is to examine the impact of students' expectation and conception of workplace learning on their transition into SWE. Analysis of accounting students' experiences reveal two broad conceptions of workplace learning, the differing impacts of which on transition experience are explored using existing learning transfer perspectives. Students displaying the more common 'technical' conception construct SWE as an opportunity to develop technical, knowledge-based expertise and abilities that prioritize product-based or cognitive learning transfer. Students with an 'experiential' conception were found to construct SWE primarily as an experience through which the development of personal skills and abilities beyond technical expertise are prioritized using process-based or socio-cultural learning transfer. Further data analysis suggests that these two learning transfer approaches have differing impacts on students' employability development which may indicate a need for universities to consider how to develop appropriate student expectations of and approaches to SWE and meaningful support for students' SWE transition
The Pagami Creek smoke plume after long-range transport to the upper troposphere over Europe – aerosol properties and black carbon mixing state
During the CONCERT 2011 field experiment with the DLR research aircraft
Falcon, an enhanced aerosol layer with particle linear depolarization ratios
of 6–8% at 532 nm was observed at altitudes above 10 km over
northeast Germany on 16 September 2011. Dispersion simulations with HYSPILT
suggest that the elevated aerosol layer originated from the Pagami Creek
forest fire in Minnesota, USA, which caused pyro-convective uplift of
particles and gases. The 3–4 day-old smoke plume had high total refractory
black carbon (rBC) mass concentrations of 0.03–0.35 μg m<sup>−3</sup>
at standard temperature and pressure (STP) with rBC mass equivalent diameter
predominantly smaller than 130 nm. Assuming a core-shell particle structure,
the BC cores exhibit very thick (median: 105–136 nm) BC-free coatings. A
large fraction of the BC-containing particles disintegrated into a BC-free
fragment and a BC fragment while passing through the laser beam of the Single
Particle Soot Photometer (SP2). In this study, the disintegration is a result
of very thick coatings around the BC cores. This is in contrast to a previous
study in a forest-fire plume, where it was hypothesized to be a result of BC
cores being attached to a BC-free particle. For the high-altitude forest-fire
aerosol layer observed in this study, increased mass specific
light-absorption cross sections of BC can be expected due to the very thick
coatings around the BC cores, while this would not be the case for the
attached-type morphology. We estimate the BC mass import from the Pagami
Creek forest fire into the upper troposphere/lower stratosphere (UTLS) region
(best estimate: 25 Mg rBC). A comparison to black carbon emission rates from
aviation underlines the importance of pyro-convection on the BC load in the
UTLS region. Our study provides detailed information on the microphysics and
the mixing state of BC in the forest-fire aerosol layer in the upper
troposphere that can be used to better understand and investigate the
radiative impact of such upper tropospheric aerosol layers
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