65 research outputs found
Unlocking the Future: Sustainable Agriculture as a Path to Prosperity for the Western Balkans
Unlocking the Future: Sustainable Agriculture as a Path to Prosperity for the Western Balkans is a study undertaken to try to assess the environmental and economic consequences of a shift to organic agriculture in the four Western Balkan countries: Bosnia and Herzegovina (BiH), Croatia, Montenegro and Serbia. The study aims to help policy makers and other stakeholders in the Western Balkan countries understand the potential positive impacts which could occur by investing in and designing sustainable policies for the agriculture sector.
One of the innovative aspects of this study is that it examines the externalities involved in agricultural production – comparing those of sustainable (organic) agriculture and conventional (high-input) agriculture. In economics, an externality is a cost or benefit which results from an activity or transaction and which affects an otherwise uninvolved party who did not choose to incur that cost or benefit. This study takes an approach which involves the economic valuation of ecosystem services and both positive and negative externalities. The authors are quite aware of the limitations of this approach. Some things have intrinsic qualities which cannot be translated well – if at all – into monetary terms. For example, how much is human life worth? How much is the existence of a species worth? How much is clean water and clean air worth? While the study contains valuations of some of these issues, this does not imply that the authors believe that these values are accurate as such. Instead, the study demonstrates the level of scale of externalities (both positive and negative) that are currently completely unaccounted for when discussing the value added of the agriculture sector.
The study has been developed in order to examine the multiple factors that go into evaluating the economic performance of agriculture beyond simple calculations of GDP. This issue is of major importance as people, businesses and governments have increasingly been realising that economic development takes place in a world with ecological and resource boundaries that impact all aspects of society. There is an imperative for a different model for development in agriculture. It is the authors’ belief that the region has a great opportunity to change this model – to move away from agricultural practices that have high negative impacts and towards an agriculture sector that is more sustainable ecologically while creating more jobs and more real value.
The study takes a regional approach with differentiation of analysis according to each country. This is because the issues faced by each country related to agriculture are often consistent, and programmes to move towards sustainable agriculture could be developed on a region-wide scale.
The study is organised into the following chapters:
Chapter 1:
Introduction discusses important global and local economic, social, and environmental issues related to conventional agricultural practices – including positive and negative externalities. It also describes the definition of sustainable agriculture to be used in the study and why this definition was chosen – focusing on organic farming. Finally, it contains a section that gives the basic information on the state of organic agriculture in each country.
Chapter 2:
Current Agricultural Policies in the Western Balkans provides background information about the policy and institutional frameworks in each of the four countries examined. This chapter also examines the level of subsidies for agriculture in each of the countries. Finally, this chapter examines the characteristics of each country’s agricultural sector in terms of human capacities, education, and information dissemination.
Chapter 3:
Research Framework and Methodology explores the objectives and relevance of the study, including summarizing the methodology and benchmark indicators used. This chapter also discusses the basic concepts behind the baseline analysed and the three different scenarios developed.
Chapter 4:
Setting up the Business as Usual Scenario examines the assumptions and other various aspects of the Business as Usual Scenario.
Chapter 5:
Setting Up the ECO and ECO+ Scenarios: A total conversion to organic farming describes the possibilities for organic farming and the assumptions that would be critical for the calculations of the impacts on the benchmark indicators.
Chapter 6:
The Baseline Situation discusses the results of the analysis of the baseline situation in terms of the statistical indicators related to the status of the agricultural sector in 2009 in the various countries – including economic evaluations of the impacts.
Chapter 7:
Development Scenarios Results contains information on the impacts of the different scenarios on the benchmark indicators.
Chapter 8:
Discussion on the Employed Methodology contains a discussion about the various aspects of the methodology and how they affected the calculations.
Chapter 9:
Summary of Key Findings and Conclusions contains a discussion of the results of the assessment and the implications for policy and practice in agriculture for the region.
Chapter 10:
Recommendations – the Way Forward contains concrete recommendations for policy-makers, practitioners and researchers in agriculture in the region.
The study concludes with 9 key findings:
Key Finding # 1: Agriculture in the Western Balkans does matter.
Key Finding #2: Current agricultural policies provide a ‘low profile’ support to organic farming.
Key Finding # 3: Current farming in the region does not create any real value added (= gross value added corrected for environmental externalities and public expenditures).
Key Finding #4: Building soil fertility and human and social capital is the key for a wider spread of organic farming.
Key Finding # 5: Conversion to organic farming provides more jobs.
Key Finding # 6: Conversion to organic farming produces more food.
Key Finding #7: Going organic is “greener”.
Key Finding # 8: Going organic is more profitable.
Key Finding #9: Business as usual is not an option
Reducing Emissions in Croatia – the Costs of Mitigation
In order to avoid dangerous climate change resulting from an increase in temperature of over 2oC, global GHG emissions must be cut by 50-85% by 2050. Croatia’s trajectory for emissions growth in the Business as Usual (BAU) case is estimated to result in 42 million tonnes of CO2e in 2020 – a significant increase from today. The EU has committed to reducing emissions by 20% by 2020. Croatia has committed to reducing emissions by an average of 5% for the period 2008-2012 from a baseline level of 36 million tonnes under the Kyoto Protocol. Croatia will also share at least part of the EU commitment for 2020, especially with respect to emissions from major point sources such as power plants and industrial sources. The energy sector is the largest source of GHG emissions in Croatia (73% in 2006). There are many potential measures to reduce emissions from the energy sector by 2020. It is estimated that by implementing the measures in the Energy Efficiency Master Plan, 1% of the national GDP could be saved. Emission reductions from households and the service industry could amount to almost 2 million tonnes by 2020 with a net economic benefit from energy cost savings. Industrial efficiency measures could also have a positive financial impact on companies. Producing electricity from renewable resources, increasing the efficiency of conversion and transmission, and – more controversially – moving to more nuclear power and electricity generated from burning waste, could yield significantly fewer emissions. Reducing fuel consumption in transportation through fuel-efficient vehicles, lower-carbon fuels, using biodiesel or other biofuels, or reducing car travel through better urban planning, public transportation, and traffic systems are also potential areas where emissions can be cut.
The agricultural sector accounts for almost 11% of Croatian emission (2006). Agriculture can play a role in reducing direct emissions from agricultural soils and improved livestock and manure management. Agriculture also has an indirect impact on emissions due to fertiliser production and emissions from transport. Finally, agriculture can have an impact on mitigation due to land use, land use changes and forestry (LULUCF) activities related to converting arable land to grassland or forests, converting drained arable land back to wetlands, or increasing soil in carbon storage management practices.
Organic farming contributes to the reduction of greenhouse gas (GHG) emissions because it reduces the consumption of fossil fuels (notably those used in fertiliser manufacturing), reduces emissions of CO2, methane and nitrogen oxides and reduces the vulnerability of soils to erosion, while at the same time increasing carbon stocks in the soil. Consequently, conversion to organic farming is considered a viable way of reducing GHG emissions. Depending on the commodity produced, organic farming emits 6-60% less GHGs than non-organic farming. Average CO2 emissions per unit area from organic beef are 57% lower than for nonorganic production. However, if there are substantially lower yields, organic farming results in higher GHGs per kg of product. Numerous studies have shown that, despite their reliance on frequent mechanical weed control, organic farming systems can increase soil organic matter stocks. Various long-term trials have shown that the annual carbon increase in soil from organic farming is 12-28%.
This Report presents seven possible mitigation scenarios. They are based on different approaches and technologies that could theoretically be applied to realise mitigation effects. One of them is the“Organic 25%”scenario, assuming the conversion of 25% of agricultural land to organic farming by 2020. It envisages the same crop and livestock mix as in 2005 and the calculation is based on a study commissioned by the UNFAO and a follow-up study. It does not take into account the carbon sequestration effect of organic management.
Of the seven examined scenarios, the “Organic 25%” and “Ruminants reduced by 25%” scenarios are the only two GHG emission mitigation scenarios exhibiting a positive net economic benefit (= benefits minus costs). The organic farming scenario benefits from the fact that the organic farming gross value added per hectare is comparable with that of non-organic production and because it saves public money invested in fertiliser manufacturing and transport. Estimated marginal costs per tonne of CO2e reduction in 2020 in the “Organic 25%” scenario ranges from -10 to -30 EUR. Its potential emissions reduction (excluding carbon sequestration) equals to 515 million tonnes CO2e, representing 1.7% of all Croatia’s GHG emissions in 2006.
While this calculation needs further analysis, it shows mitigation costs (actually benefits) and GHG emissions reduction potential of a wide-spread adoption of organic farming. However, while potential does exist and seems achievable at no cost, there are many political, institutional, technical, and other considerations that would have to be resolved to reach this
Secular Dynamical Anti-Friction in Galactic Nuclei
We identify a gravitational-dynamical process in near-Keplerian potentials of
galactic nuclei that occurs when an intermediate-mass black hole (IMBH) is
migrating on an eccentric orbit through the stellar cluster towards the central
supermassive black hole (SMBH). We find that, apart from conventional dynamical
friction, the IMBH experiences an often much stronger systematic torque due to
the secular (i.e., orbit-averaged) interactions with the cluster's stars. The
force which results in this torque is applied, counterintuitively, in the same
direction as the IMBH's precession and we refer to its action as
"secular-dynamical anti-friction" (SDAF). We argue that SDAF, and not the
gravitational ejection of stars, is responsible for the IMBH's eccentricity
increase seen in the initial stages of previous N-body simulations. Our
numerical experiments, supported by qualitative arguments, demonstrate that (1)
when the IMBH's precession direction is artificially reversed, the torque
changes sign as well, which decreases the orbital eccentricity, (2) the rate of
eccentricity growth is sensitive to the IMBH migration rate, with zero
systematic eccentricity growth for an IMBH whose orbit is artificially
prevented from inward migration, and (3) SDAF is the strongest when the central
star cluster is rapidly rotating. This leads to eccentricity growth/decrease
for the clusters rotating in the opposite/same direction relative to the IMBH's
orbital motion.Comment: 8 pages, 7 figures, Published in Ap
Quantum theory of optical temporal phase and instantaneous frequency
We propose a general quantum theory of optical phase and instantaneous
frequency in the time domain for slowly varying optical signals. Guided by
classical estimation theory, we design homodyne phase-locked loops that enable
quantum-limited measurements of temporal phase and instantaneous frequency.
Standard and Heisenberg quantum limits to such measurements are then derived.
For optical sensing applications, we propose multipass and Fabry-P\'erot
position and velocity sensors that take advantage of the signal-to-noise-ratio
enhancement effect of wideband angle modulation without requiring nonclassical
light. We also generalize our theory to three spatial dimensions for
nonrelativistic bosons and define an Hermitian fluid velocity operator, which
provides a theoretical underpinning to the current-algebra approach of quantum
hydrodynamics.Comment: 16 pages, v3: rewritten and extended, v4: some minor mistakes
corrected, accepted by Physical Review
The Search for eta(1440) --> K^0_S K^pm \pi^mp in Two-Photon Fusion at CLEO
We analyze 13.8 \rm fb^{-1} of the integrated e^+e^- luminosity collected at
10.6 GeV center-of-mass energy with the CLEO II and CLEO II.V detectors to
study exclusive two-photon production of hadrons with masses below 1.7{\rm \
GeV/c^2} decaying into the K^0_S K^\pm \pi^\mp final state. We observe two
statistically significant enhancements in the \eta(1440) mass region. These
enhancements have large transverse momentum which rules them out as being due
to pseudoscalar resonances but is consistent with the production of
axial-vector mesons. We use tagged two-photon events to study the properties of
the observed enhancements and associate them with the production of f_1(1285)
and f_1(1420). Our non-observation of \eta(1440) is inconsistent by more than
two standard deviations with the first observation of this resonance in
two-photon collisions by the L3 experiment. We present our estimates for 90%
confidence level upper limits on the products of two-photon partial widths of
pseudoscalar hadrons and their branching fractions into
K^0_S(\pi^+\pi^-)K^\pm\pi^\mp.Comment: 24 pages postscript,also available through
http://www.lns.cornell.edu/public/CLNS/2004/, submitted to PR
Heavy quarkonium: progress, puzzles, and opportunities
A golden age for heavy quarkonium physics dawned a decade ago, initiated by
the confluence of exciting advances in quantum chromodynamics (QCD) and an
explosion of related experimental activity. The early years of this period were
chronicled in the Quarkonium Working Group (QWG) CERN Yellow Report (YR) in
2004, which presented a comprehensive review of the status of the field at that
time and provided specific recommendations for further progress. However, the
broad spectrum of subsequent breakthroughs, surprises, and continuing puzzles
could only be partially anticipated. Since the release of the YR, the BESII
program concluded only to give birth to BESIII; the -factories and CLEO-c
flourished; quarkonium production and polarization measurements at HERA and the
Tevatron matured; and heavy-ion collisions at RHIC have opened a window on the
deconfinement regime. All these experiments leave legacies of quality,
precision, and unsolved mysteries for quarkonium physics, and therefore beg for
continuing investigations. The plethora of newly-found quarkonium-like states
unleashed a flood of theoretical investigations into new forms of matter such
as quark-gluon hybrids, mesonic molecules, and tetraquarks. Measurements of the
spectroscopy, decays, production, and in-medium behavior of c\bar{c}, b\bar{b},
and b\bar{c} bound states have been shown to validate some theoretical
approaches to QCD and highlight lack of quantitative success for others. The
intriguing details of quarkonium suppression in heavy-ion collisions that have
emerged from RHIC have elevated the importance of separating hot- and
cold-nuclear-matter effects in quark-gluon plasma studies. This review
systematically addresses all these matters and concludes by prioritizing
directions for ongoing and future efforts.Comment: 182 pages, 112 figures. Editors: N. Brambilla, S. Eidelman, B. K.
Heltsley, R. Vogt. Section Coordinators: G. T. Bodwin, E. Eichten, A. D.
Frawley, A. B. Meyer, R. E. Mitchell, V. Papadimitriou, P. Petreczky, A. A.
Petrov, P. Robbe, A. Vair
Observation of J/psi --> 3 gamma
We report the first observation of the decay J/psi --> 3 gamma. The signal
has a statistical significance of 6 sigma and corresponds to a branching
fraction of B(J/psi --> 3 gamma) = (1.2 +- 0.3 +- 0.2) x 10^-5, in which the
errors are statistical and systematic, respectively. The measurement uses
psi(2S) --> pi+ pi- J/psi events acquired with the CLEO-c detector operating at
the CESR e+e- collider.Comment: 11 pages, available through http://www.lns.cornell.edu/public/CLNS/,
submitted to PR
Dynamic Effective Connectivity of Inter-Areal Brain Circuits
Anatomic connections between brain areas affect information flow between neuronal circuits and the synchronization of neuronal activity. However, such structural connectivity does not coincide with effective connectivity (or, more precisely, causal connectivity), related to the elusive question “Which areas cause the present activity of which others?”. Effective connectivity is directed and depends flexibly on contexts and tasks. Here we show that dynamic effective connectivity can emerge from transitions in the collective organization of coherent neural activity. Integrating simulation and semi-analytic approaches, we study mesoscale network motifs of interacting cortical areas, modeled as large random networks of spiking neurons or as simple rate units. Through a causal analysis of time-series of model neural activity, we show that different dynamical states generated by a same structural connectivity motif correspond to distinct effective connectivity motifs. Such effective motifs can display a dominant directionality, due to spontaneous symmetry breaking and effective entrainment between local brain rhythms, although all connections in the considered structural motifs are reciprocal. We show then that transitions between effective connectivity configurations (like, for instance, reversal in the direction of inter-areal interactions) can be triggered reliably by brief perturbation inputs, properly timed with respect to an ongoing local oscillation, without the need for plastic synaptic changes. Finally, we analyze how the information encoded in spiking patterns of a local neuronal population is propagated across a fixed structural connectivity motif, demonstrating that changes in the active effective connectivity regulate both the efficiency and the directionality of information transfer. Previous studies stressed the role played by coherent oscillations in establishing efficient communication between distant areas. Going beyond these early proposals, we advance here that dynamic interactions between brain rhythms provide as well the basis for the self-organized control of this “communication-through-coherence”, making thus possible a fast “on-demand” reconfiguration of global information routing modalities
Post-mortem assessment in vascular dementia: advances and aspirations.
BACKGROUND: Cerebrovascular lesions are a frequent finding in the elderly population. However, the impact of these lesions on cognitive performance, the prevalence of vascular dementia, and the pathophysiology behind characteristic in vivo imaging findings are subject to controversy. Moreover, there are no standardised criteria for the neuropathological assessment of cerebrovascular disease or its related lesions in human post-mortem brains, and conventional histological techniques may indeed be insufficient to fully reflect the consequences of cerebrovascular disease. DISCUSSION: Here, we review and discuss both the neuropathological and in vivo imaging characteristics of cerebrovascular disease, prevalence rates of vascular dementia, and clinico-pathological correlations. We also discuss the frequent comorbidity of cerebrovascular pathology and Alzheimer's disease pathology, as well as the difficult and controversial issue of clinically differentiating between Alzheimer's disease, vascular dementia and mixed Alzheimer's disease/vascular dementia. Finally, we consider additional novel approaches to complement and enhance current post-mortem assessment of cerebral human tissue. CONCLUSION: Elucidation of the pathophysiology of cerebrovascular disease, clarification of characteristic findings of in vivo imaging and knowledge about the impact of combined pathologies are needed to improve the diagnostic accuracy of clinical diagnoses
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