364 research outputs found
High food prices: The what, who, and how of proposed policy actions
"The complex causes of the current food and agriculture crisis require a comprehensive response. In view of the urgency of assisting people and countries in need, the first set of policy actions— an emergency package—consists of steps that can yield immediate impact: 1. expand emergency responses and humanitarian assistance to food-insecure people and people threatening government legitimacy, 2. eliminate agricultural export bans and export restrictions, 3. undertake fast-impact food production programs in key areas, and 4. change biofuel policies. A second set of actions—a resilience package—consists of the following steps: 5. calm markets with the use of market-oriented regulation of speculation, shared public grain stocks, strengthened food-import financing, and reliable food aid; 6. invest in social protection; 7. scale up investments for sustained agricultural growth; and 8. complete the Doha Round of World Trade Organization (WTO) negotiations. Investment in these actions calls for additional resources. Policymakers should consider mobilizing resources from four sources: the winners from the commodity boom among countries; the community of traditional and new donor countries; direct or indirect progressive taxation and reallocation of public expenditures in the affected countries themselves; and mobilization of private sector finance, including through improved outreach of banking to agriculture. Because of countries' diverse situations, the design of programs must be country driven and country owned. Accountability for sound implementation must also rest with countries. At the same time, a new international architecture for the governance of agriculture, food, and nutrition is needed to effectively implement the initiatives described, and especially their international public goods components. Global and national action is needed, through existing mechanisms, well-coordinated special initiatives, and possibly a special fund." from TextFood prices, Food supply, Food demand, Social protection, Agricultural research, Agricultural policy, Agricultural subsidies,
Inverse scattering of dispersive stratified structures
We consider the inverse scattering problem of retrieving the structural
parameters of a stratified medium consisting of dispersive materials, given
knowledge of the complex reflection coefficient in a finite frequency range. It
is shown that the inverse scattering problem does not have a unique solution in
general. When the dispersion is sufficiently small, such that the time-domain
Fresnel reflections have durations less than the round-trip time in the layers,
the solution is unique and can be found by layer peeling. Numerical examples
with dispersive and lossy media are given, demonstrating the usefulness of the
method for e.g. THz technology
Activation of Liver X Receptors and Peroxisome Proliferator-Activated Receptors by Lipid Extracts of Brown Seaweeds:A Potential Application in Alzheimer’s Disease?
The nuclear liver X receptors (LXRα/β) and peroxisome proliferator-activated receptors (PPARα/γ) are involved in the regulation of multiple biological processes, including lipid metabolism and inflammation. The activation of these receptors has been found to have neuroprotective effects, making them interesting therapeutic targets for neurodegenerative disorders such as Alzheimer's Disease (AD). The Asian brown seaweed Sargassum fusiforme contains both LXR-activating (oxy)phytosterols and PPAR-activating fatty acids. We have previously shown that dietary supplementation with lipid extracts of Sargassum fusiforme prevents disease progression in a mouse model of AD, without inducing adverse effects associated with synthetic pan-LXR agonists. We now determined the LXRα/β- and PPARα/γ-activating capacity of lipid extracts of six European brown seaweed species ( Alaria esculenta, Ascophyllum nodosum, Fucus vesiculosus, Himanthalia elongata, Saccharina latissima, and Sargassum muticum) and the Asian seaweed Sargassum fusiforme using a dual luciferase reporter assay. We analyzed the sterol and fatty acid profiles of the extracts by GC-MS and UPLC MS/MS, respectively, and determined their effects on the expression of LXR and PPAR target genes in several cell lines using quantitative PCR. All extracts were found to activate LXRs, with the Himanthalia elongata extract showing the most pronounced efficacy, comparable to Sargassum fusiforme, for LXR activation and transcriptional regulation of LXR-target genes. Extracts of Alaria esculenta, Fucus vesiculosus, and Saccharina latissima showed the highest capacity to activate PPARα, while extracts of Alaria esculenta, Ascophyllum nodosum, Fucus vesiculosus, and Sargassum muticum showed the highest capacity to activate PPARγ, comparable to Sargassum fusiforme extract. In CCF-STTG1 astrocytoma cells, all extracts induced expression of cholesterol efflux genes ( ABCG1, ABCA1, and APOE) and suppressed expression of cholesterol and fatty acid synthesis genes ( DHCR7, DHCR24, HMGCR and SREBF2, and SREBF1, ACACA, SCD1 and FASN, respectively). Our data show that lipophilic fractions of European brown seaweeds activate LXRs and PPARs and thereby modulate lipid metabolism. These results support the potential of brown seaweeds in the prevention and/or treatment of neurodegenerative diseases and possibly cardiometabolic and inflammatory diseases via concurrent activation of LXRs and PPARs. </p
UNC13A in amyotrophic lateral sclerosis: from genetic association to therapeutic target
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease with limited treatment options and an incompletely understood pathophysiology. Although genomewide association studies (GWAS) have advanced our understanding of the disease, the precise manner in which risk polymorphisms contribute to disease pathogenesis remains unclear. Of relevance, GWAS have shown that a polymorphism (rs12608932) in the UNC13A gene is associated with risk for both ALS and frontotemporal dementia (FTD). Homozygosity for the C-allele at rs12608932 modifies the ALS phenotype, as these patients are more likely to have bulbar-onset disease, cognitive impairment and FTD at baseline as well as shorter survival. UNC13A is expressed in neuronal tissue and is involved in maintaining synaptic active zones, by enabling the priming and docking of synaptic vesicles. In the absence of functional TDP-43, risk variants in UNC13A lead to the inclusion of a cryptic exon in UNC13A messenger RNA, subsequently leading to nonsense mediated decay, with loss of functional protein. Depletion of UNC13A leads to impaired neurotransmission. Recent discoveries have identified UNC13A as a potential target for therapy development in ALS, with a confirmatory trial with lithium carbonate in UNC13A cases now underway and future approaches with antisense oligonucleotides currently under consideration. Considering UNC13A is a potent phenotypic modifier, it may also impact clinical trial outcomes. This present review describes the path from the initial discovery of UNC13A as a risk gene in ALS to the current therapeutic options being explored and how knowledge of its distinct phenotype needs to be taken into account in future trials
Long-range potential fluctuations and 1/f noise in hydrogenated amorphous silicon
We present a microscopic theory of the low-frequency voltage noise (known as
"1/f" noise) in micrometer-thick films of hydrogenated amorphous silicon. This
theory traces the noise back to the long-range fluctuations of the Coulomb
potential produced by deep defects, thereby predicting the absolute noise
intensity as a function of the distribution of defect activation energies. The
predictions of this theory are in very good agreement with our own experiments
in terms of both the absolute intensity and the temperature dependence of the
noise spectra.Comment: 8 pages, 3 figures, several new parts and one new figure are added,
but no conceptual revision
A sensorimotor control framework for understanding emotional communication and regulation
Action Contro
Los altos precios de los alimentos: El ‘qué', ‘quién' y ‘cómo' de las acciones de política propuestas
"La complejidad de las causas de la actual crisis alimentaria y agrícola requiere de una respuesta integral. En vista de que es urgente prestar asistencia a las poblaciones y los países necesitados, la primera serie de acciones de política —un paquete de emergencia— consiste en varios pasos para generar un impacto inmediato: 1. Incrementar las acciones de emergencia y la ayuda humanitaria para incluir a las poblaciones que experimentan inseguridad alimentaria y a las que amenazan la legitimidad gubernamental; 2. Eliminar la prohibición y las restricciones a las exportaciones agrícolas; 3. Emprender programas que permitan rápidamente expandir la oferta alimentaria en áreas clave; y, 4. Modificar las políticas de los biocombustibles. Una segunda serie de acciones de política —un paquete de resiliencia socioeconómica— consiste en los siguientes pasos: 5. Proveer tranquilidad en los mercados mediante una regulación de los movimientos especulativos a través de instrumentos de mercado, reservas públicas y compartidas de granos, un mayor financiamiento para la importación de alimentos, y una ayuda alimentaria confiable; 6. Invertir en protección social; 7. Incrementar paulatinamente las inversiones para un crecimiento agrícola sostenido; y, 8. Concluir las negociaciones de la Ronda de Doha de la Organización Mundial del Comercio (OMC). La inversión en estas acciones requiere de recursos adicionales. Las instancias decisorias deberán considerar la movilización de recursos provenientes de cuatro fuentes: los países que se han beneficiado del auge de los commodities agrícolas; la comunidad de países donantes, tanto tradicionales como nuevos; impuestos proporcionales, directos o indirectos, y la reasignación del gasto público en los propios países afectados; y la movilización de los recursos financieros del sector privado, lo que incluye una ampliación en la cobertura de los servicios financieros para la agricultura. Debido a las diversas situaciones que enfrentan, los mismos países deben dirigir y apropiarse del diseño de los programas. La rendición de cuentas en cuanto a una implementación acertada también deberá recaer en los países. Al mismo tiempo, se necesita una nueva estructura internacional de gobernabilidad para la agricultura, la alimentación y la nutrición, a fin de implementar de forma eficaz las iniciativas descritas, especialmente los componentes relativos a los bienes públicos internacionales. También es necesaria la acción, tanto en el ámbito mundial como nacional, a través de los mecanismos existentes, iniciativas especiales muy bien coordinadas y posiblemente un fondo especial." from TextFood prices, Food supply, Food demand, Social protection, Agricultural research, Agricultural policy, Agricultural subsidies,
Analysis of FUS, PFN2, TDP-43, and PLS3 as potential disease severity modifiers in spinal muscular atrophy
Objective To investigate mutations in genes that are potential modifiers of spinal muscular atrophy (SMA) severity. Methods We performed a hypothesis-based search into the presence of variants in fused in sarcoma (FUS), transactive response DNA-binding protein 43 (TDP-43), plastin 3 (PLS3), and profilin 2 (PFN2) in a cohort of 153 patients with SMA types 1-4, including 19 families. Variants were detected with targeted next-generation sequencing and confirmed with Sanger sequencing. Functional effects of the identified variants were analyzed in silico and for PLS3, by analyzing expression levels in peripheral blood. Results We identified 2 exonic variants in FUS exons 5 and 6 (p.R216C and p.S135N) in 2 unrelated patients, but clinical effects were not evident. We identified 8 intronic variants in PLS3 in 33 patients. Five PLS3 variants (c.1511+82T>C; c.748+130 G>A; c.367+182C>T; c.891-25T>C (rs145269469); c.1355+17A>G (rs150802596)) potentially alter exonic splice silencer or exonic splice enhancer sites. The variant c.367+182C>T, but not RNA expression levels, corresponded with a more severe phenotype in 1 family. However, this variant or level of PLS3 expression did not consistently correspond with a milder or more severe phenotype in other families or the overall cohort. We found 3 heterozygous, intronic variants in PFN2 and TDP-43 with no correlation with clinical phenotype or effects on splicing. Conclusions PLS3 and FUS sequence variants do not modify SMA severity at the population level. Specific variants in individual patients or families do not consistently correlate with disease severity
Hohe Nahrungsmittelpreise: Konzept f �r die Wege aus der Krise
"Die vielschichtigen Ursachen der gegenw�rtigen Krise im Bereich der Nahrungsmittelproduktion und Landwirtschaft erfordern eine umfassende globale Antwort. Angesichts der dringend benötigen Hilfe besteht der erste Ma�nahmenkatalog – ein Notfallpaket – aus Programmen, die sofort wirken: 1. Ausweiten der Soforthilfe und der humanit�ren Unterst�tzung f�r Menschen, deren Versorgung nicht gesichert ist, sowie dort, wo die Legitimit�t der Regierung bedroht ist 2. Abschaffung der landwirtschaftlichen Exportverbote und Exportbeschr�nkungen 3. Durchf�hrung von Programmen, die Nahrungsmittelproduktion in wichtigen Regionen steigern und schnell wirksam sind 4. �nderung der Agrar-Treibstoffpolitik Der zweite Ma�nahmenkatalog – ein Nachhaltigkeitspaket – besteht aus folgenden Komponenten: 5. Beruhigung der M�rkte durch marktorientierte Regulierung der Spekulation, Koordination öffentlicher Getreidevorr�te, Finanzierung von Nahrungsmittelimporten und verl�ssliche Nahrungsmittelhilfe in armen L�ndern 6. investieren in Ma�nahmen zur sozialen Absicherung 7. Ausweitung des Investitionsvolumens f�r nachhaltiges landwirtschaftliches Wachstum und 8. erfolgreicher Abschluss der Verhandlungen im Rahmen der Doha Runde der Welthandelsorganisation (WTO) Diese Ma�nahmen erfordern zus�tzliche finanzielle Ressourcen. Die Politik sollte daf�r vier Quellen ins Auge fassen: (1) die L�nder, die als Gewinner aus dem Rohstoffboom hervorgegangen sind, (2) die Gemeinschaft der alten und neuen Geberl�nder, (3) direkte oder indirekte progressive Besteuerung und Umschichtung der öffentlichen Ausgaben in den betroffenen L�ndern selbst, (4) Mobilisierung von Finanzmitteln des privaten Sektors, u.a. durch ein verst�rktes Engagement des Bankwesens in der Landwirtschaft. Aufgrund der unterschiedlichen Lage, in der sich die L�nder befinden, muss die Planung der Programme vom jeweiligen Land gef�hrt werden. Die L�nder sind auch verantwortlich f�r eine solide Implementierung ihrer Programme. Gleichzeitig wird eine straffere internationale Architektur f�r die Politik in den Bereichen Landwirtschaft, Nahrungsmittel und Ern�hrung gefordert, um die oben beschriebenen Initiativen wirksam zu implementieren; besonders die Komponenten, die öffentliche G�ter betreffen. Die Umsetzung der Ma�nahmen auf globaler und nationaler Ebene sollte mit existierenden Mechanismen und gut aufeinander abgestimmten speziellen Initiativen erfolgen. Ein �Sonderfonds zur Weltern�hrung“ w�rde die f�r eine effektive Koordination notwendigen Anreize schaffen." from TextFood prices, Food supply, Food demand, Social protection, Agricultural research, Agricultural policy, Agricultural subsidies,
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