1,680 research outputs found
Gesellschaftliche Leistungen der biologischen Landwirtschaft
Zusammenfassuung:
In diesem Bericht werden die wissenschaftlichen Ergebnisse nationaler und internationaler Studien zu den gesellschaftlichen Leistungen des Biolandbaus zusammengefasst. Als Referenzen werden dabei sowohl die konventionelle wie auch die integrierte Landwirtschaft herangezogen.
Es ist den Autoren bewusst, dass alle Landwirtschaftsmethoden in der Schweiz und im Ausland eine grosse Streubreite aufweisen, da der Einfluss der regionalen sozioökonomischen Rahmenbedingungen, der Standortfaktoren, der Betriebsleiter und der unterschiedlichen staatlichen und privaten Regulierungen gross ist. Trotzdem ergeben sich fĂŒr die verschiedenen Landwirtschaftsmethoden klare Unterschiede, die bei den agrarpolitischen Massnahmen berĂŒcksichtigt werden mĂŒssen.
BezĂŒglich der positiven ExternalitĂ€ten weist der Biolandbau klare Mehrleistungen in der BiodiversitĂ€t auf. Dies sowohl auf der Ebene der Genetik, der Arten und besonders auch der Habitate. Deutlich sind die Mehrleistungen des Biolandbaus auch im Bereich des Humusaufbaus, was eine höhere CO2-Sequestrierung zur Folge hat.
Obwohl eine dauerhafte Honorierung der Vermeidung negativer ExternalitÀten im bisherigen Konzept der Weiterentwicklung des Direktzahlungssystems (WDZ) nicht vorgesehen ist, sind
hier die Vorteile der biologischen Landwirtschaft betrÀchtlich. Dies betrifft die NÀhrstoff- und Pflanzenschutzmittelverluste in Grund- und OberflÀchengewÀsser sowie in andere Umweltkompartimente, der Verbrauch von nicht erneuerbarer Energie, die Emissionen von Klimagasen und die Belastungen mit Tiermedikamenten.
Die nationalen und internationalen Studien zeigen auf, dass der Biolandbau sich besonders durch Systemwirkungen auszeichnet: erhöhte BiodiversitĂ€t, verbesserter Schutz des Bodens, wirksame Vermeidung von Umweltbelastungen, effiziente Nutzung von natĂŒrlichen Ressourcen, geringer Verbrauch nicht erneuerbarer Energie und verbessertes Tierwohl. Dies sind die Effekte von komplexen Response-Massnahmen der Betriebsleiter auf einfach zu kontrollierende EinschrĂ€nkungen und Verbote. Dadurch entstehen nicht zu unterschĂ€tzende Zusatzleistungen und Synergien bei der Erreichung der vom Bund definierten Ziele.
Um den Mehrleistungen des Biolandbaus gerecht zu werden, schlagen die Autoren zwei neue Massnahmen vor:
1) BiodiversitĂ€tsbeitrag fĂŒr Acker, Sonderkulturen und intensive Wiesen und
2) CO2-SequestrationsbeitrÀge.
Damit sind aber die gesellschaftlich wichtigen Mehrleistungen des Biolandbaus noch nicht abgegolten. Bei der Vermeidung negativer ExternalitÀten werden höhere umweltschutzrelevante Effekte erzielt.
Diese können
i) durch die EinfĂŒhrung eines negativen Anreizsystems nach dem Polluter-Pays-Principle (z.B. Stickstoffsteuer, CO2 - Abgabe),
ii) durch ein höheres Einstiegsniveau bei den Cross-Compliance-Massnahmen fĂŒr alle Betriebe (ĂLNplus) oder
iii) durch einen finanziellen Ausgleich fĂŒr die Mehrleistungen des Biolandbaus abgegolten werden.
Die âFörderung des Biolandbausâ als systemorientierte Massnahme macht auch nach dem Grundsatz des effizienten Einsatzes von Steuermitteln Sinn und stellt eine kosteneffektive Massnahme dar. Einerseits können damit die deutlich höheren positiven ExternalitĂ€ten abgegolten werden, andererseits wird die stĂ€rkere Vermeidung von negativen ExternalitĂ€ten genĂŒgend berĂŒcksichtigt
Abrupt changes in alpha decay systematics as a manifestation of collective nuclear modes
An abrupt change in decay systematics around the N=126 neutron shell
closure is discussed. It is explained as a sudden hindrance of the clustering
of the nucleons that eventually form the particle. This is because the
clustering induced by the pairing mode acting upon the four nucleons is
inhibited if the configuration space does not allow a proper manifestation of
the pairing collectivity.Comment: 6 pages, 3 figures, submitted to Phys. Rev. C, a few new references
adde
Alpha Decay Hindrance Factors: A Probe of Mean Field Wave Functions
A simple model to calculate alpha-decay Hindrance Factors is presented. Using
deformation values obtained from PES calculations as the only input, Hindrance
Factors for the alpha-decay of Rn- and Po-isotopes are calculated. It is found
that the intrinsic structure around the Fermi surface determined by the
deformed mean field plays an important role in determining the hindrance of
alpha-decay. The fair agreement between experimental and theoretical Hindrance
Factors suggest that the wave function obtained from the energy minima of the
PES calculations contains an important part of the correlations that play a
role for the alpha-decay. The calculated HF that emerges from these
calculations render a different interpretation than the commonly assumed
n-particle n-hole picture.Comment: 7 pages, 9 figure
Can Action Research Strengthen District Health Management and Improve Health Workforce Performance? A Research Protocol.
The single biggest barrier for countries in sub-Saharan Africa (SSA) to scale up the necessary health services for addressing the three health-related Millennium Development Goals and achieving Universal Health Coverage is the lack of an adequate and well-performing health workforce. This deficit needs to be addressed both by training more new health personnel and by improving the performance of the existing and future health workforce. However, efforts have mostly been focused on training new staff and less on improving the performance of the existing health workforce. The purpose of this paper is to disseminate the protocol for the PERFORM project and reflect on the key challenges encountered during the development of this methodology and how they are being overcome. The overall aim of the PERFORM project is to identify ways of strengthening district management in order to address health workforce inadequacies by improving health workforce performance in SSA. The study will take place in three districts each in Ghana, Tanzania and Uganda using an action research approach. With the support of the country research teams, the district health management teams (DHMTs) will lead on planning, implementation, observation, reflection and redefinition of the activities in the study. Taking into account the national and local human resource (HR) and health systems (HS) policies and practices already in place, 'bundles' of HR/HS strategies that are feasible within the context and affordable within the districts' budget will be developed by the DHMTs to strengthen priority areas of health workforce performance. A comparative analysis of the findings from the three districts in each country will add new knowledge on the effects of these HR/HS bundles on DHMT management and workforce performance and the impact of an action research approach on improving the effectiveness of the DHMTs in implementing these interventions. Different challenges were faced during the development of the methodology. These include the changing context in the study districts, competing with other projects and duties for the time of district managers, complexity of the study design, maintaining the anonymity and confidentiality of study participants as well as how to record the processes during the study. We also discuss how these challenges are being addressed. The dissemination of this research protocol is intended to generate interest in the PERFORM project and also stimulate discussion on the use of action research in complex studies such as this on strengthening district health management to improve health workforce performance
Magnetization reversal of an individual exchange biased permalloy nanotube
We investigate the magnetization reversal mechanism in an individual
permalloy (Py) nanotube (NT) using a hybrid magnetometer consisting of a
nanometer-scale SQUID (nanoSQUID) and a cantilever torque sensor. The Py NT is
affixed to the tip of a Si cantilever and positioned in order to optimally
couple its stray flux into a Nb nanoSQUID. We are thus able to measure both the
NT's volume magnetization by dynamic cantilever magnetometry and its stray flux
using the nanoSQUID. We observe a training effect and temperature dependence in
the magnetic hysteresis, suggesting an exchange bias. We find a low blocking
temperature K, indicating the presence of a thin
antiferromagnetic native oxide, as confirmed by X-ray absorption spectroscopy
on similar samples. Furthermore, we measure changes in the shape of the
magnetic hysteresis as a function of temperature and increased training. These
observations show that the presence of a thin exchange-coupled native oxide
modifies the magnetization reversal process at low temperatures. Complementary
information obtained via cantilever and nanoSQUID magnetometry allows us to
conclude that, in the absence of exchange coupling, this reversal process is
nucleated at the NT's ends and propagates along its length as predicted by
theory.Comment: 8 pages, 4 figure
Glasslike Arrest in Spinodal Decomposition as a Route to Colloidal Gelation
Colloid-polymer mixtures can undergo spinodal decomposition into colloid-rich
and colloid-poor regions. Gelation results when interconnected colloid-rich
regions solidify. We show that this occurs when these regions undergo a glass
transition, leading to dynamic arrest of the spinodal decomposition. The
characteristic length scale of the gel decreases with increasing quench depth,
and the nonergodicity parameter exhibits a pronounced dependence on scattering
vector. Mode coupling theory gives a good description of the dynamics, provided
we use the full static structure as input.Comment: 14 pages, 4 figures; replaced with published versio
Left bundle branch block causes relative but not absolute septal underperfusion during exercise
Aims Left bundle branch block (LBBB) often causes septal perfusion defects in radionuclide myocardial perfusion imaging using exercise (Ex) but rarely using vasodilator stress. We studied whether this is due to an underlying structural disease inherent to spontaneous LBBB or whether it is also found in temporary LBBB induced by right ventricular pacing (PM) indicating a functional rather than a structural alteration. Methods and results Regional myocardial blood flow (MBF) at rest and at Ex was measured with(15)O-H(2)O and PET in 10 age-matched healthy volunteers (controls), 10 LBBB patients and 10 PM patients with right ventricular pacing off and on (PM off and PM on). Although at Ex septal MBF tended to be higher in LBBB than in controls (3.04 +/- 1.18 vs. 2.27 +/- 0.72 mL/min/g; P= ns), the ratio septal/lateral MBF was 19% lower in LBBB than in controls (P < 0.05). Similarly, switching PM on at Ex decreased the ratio septal/lateral MBF by 17% (P < 0.005). Conclusion The apparent septal perfusion defect in LBBB is mainly due to a relative lateral hyperperfusion rather than to an absolute septal flow decrease. This pattern seems to be reversibly inducible by right ventricular pacing, suggesting a functional rather than a structural alteratio
The catalytic subunit of Plasmodium falciparum casein kinase 2 is essential for gametocytogenesis
Casein kinase 2 (CK2) is a pleiotropic kinase phosphorylating substrates in different cellular compartments in eukaryotes. In the malaria parasite Plasmodium falciparum, PfCK2 is vital for asexual proliferation of blood-stage parasites. Here, we applied CRISPR/Cas9-based gene editing to investigate the function of the PfCK2alpha catalytic subunit in gametocytes, the sexual forms of the parasite that are essential for malaria transmission. We show that PfCK2alpha localizes to the nucleus and cytoplasm in asexual and sexual parasites alike. Conditional knockdown of PfCK2alpha expression prevented the transition of stage IV into transmission-competent stage V gametocytes, whereas the conditional knockout of pfck2a completely blocked gametocyte maturation already at an earlier stage of sexual differentiation. In summary, our results demonstrate that PfCK2alpha is not only essential for asexual but also sexual development of P. falciparum blood-stage parasites and encourage studies exploring PfCK2alpha as a potential target for dual-active antimalarial drugs
Healthy aging in elderly cochlear implant recipients: a multinational observational study
Background: Given an increase in the aging population and its impact on healthcare systems, policy makers for
provision of health and social services are aiming to keep older adults in good health for longer, in other words
towards âhealthy agingâ. Our study objective is to show that rehabilitation with cochlear implant treatment in the
elderly with hearing impairment improves the overall health-related quality of life and general well-being that
translate into healthy aging.
Methods: The multicentre, prospective, repeated measures, single-subject, clinical observational study will accrue
100 elderly, first-time, unilateral CI recipients (â„ 60 years) and analyze changes on specific measurement tools over
ca. 20 months from preimplant to postimplant. Evaluations will consist of details collected through case history and
interview questionnaires by clinicians, data logging, self-report questionnaires completed by the recipients and a
series of commonly used audiometric measures and geriatric assessment tools. The primary indicator of changes in
overall quality of life will be the HUI-3.
Discussion: The protocol is designed to make use of measurement tools that have already been applied to the
hearing-impaired population in order to compare effects of CI rehabilitation in adults immediately before their
implantation, (pre-implant) and after gaining 1â1.5 years of experience (post-implant). The broad approach will lead
to a greater understanding of how useful hearing impacts the quality of life in elderly individuals, and thus
improves potentials for healthy aging. Outcomes will be described and analyzed in detail.
Trial registration: This research has been registered in ClinicalTrials.gov (http://www.clinicaltrials.gov/), 7 March
2017 under the n° NCT03072862
c-Maf enforces cytokine production and promotes memory-like responses in mouse and human type 2 innate lymphoid cells
Group-2 innate lymphoid cells (ILC2s), which are involved in type 2 inflammatory diseases such as allergy, can exhibit immunological memory, but the basis of this ILC2 "trained immunity" has remained unclear. Here, we found that stimulation with IL-33/IL-25 or exposure to the allergen papain induces the expression of the transcription factor c-Maf in mouse ILC2s. Chronic papain exposure results in high production of IL-5 and IL-13 cytokines and lung eosinophil recruitment, effects that are blocked by c-Maf deletion in ILCs. Transcriptomic analysis revealed that knockdown of c-Maf in ILC2s suppresses expression of type 2 cytokine genes, as well as of genes linked to a memory-like phenotype. Consistently, c-Maf was found highly expressed in human adult ILC2s but absent in cord blood and required for cytokine production in isolated human ILC2s. Furthermore, c-Maf-deficient mouse or human ILC2s failed to exhibit strengthened (âtrainedâ) responses upon repeated challenge. Thus, the expression of c-Maf is indispensable for optimal type 2 cytokine production and proper memory-like responses in group-2 innate lymphoid cells
- âŠ