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1.
Sci Rep ; 13(1): 12252, 2023 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-37507434

RESUMEN

Current land use systems in the Amazon largely consist of extensive conventional productivist livestock operations that drive deforestation. Silvopastoral systems (SPS) support a transition to low carbon production if they intensify in sympathy with the needs of biophysical and socio-economic contexts. SPS have been promoted for decades as an alternative livestock production system but widespread uptake has yet to be seen. We provide a schema of associating factors for adoption of SPS based on past literature in tropical agriculture and apply this to a bespoke survey of 172 farms in the Caquetá region of the Colombian Amazon. We find a number of factors which do not apply to this region and argue for a context specific approach. The impact of managing increased market access and opportunities for SPS producers are crucial to avoiding additional deforestation. Further understanding of the underlying antecedents of common factors, such as perceptions of silvopastoral systems, would reduce the risk of perverse policy outcomes.


Asunto(s)
Agricultura , Políticas , Colombia , Granjas , Carbono , Conservación de los Recursos Naturales
2.
J Environ Manage ; 129: 9-17, 2013 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-23792885

RESUMEN

Increasing financial pressures has led farmers to manage cattle outside for the winter months. In temperate areas the environmental risks of outwintering cattle are exacerbated by cooler and wetter weather and identifying how farmers perceive these risks is essential to understanding how potential hazards could be mitigated. A series of workshops were conducted with cattle producers in England and Wales to understand their perceptions of the risks, their decision-making with respect to outwintering and their options for mitigating these risks. A range of risks were identified, but emphasis was placed on environmentally-related risks, such as soil damage, and on social risks, such as public perception of their treatment of the animals. The uncertainties due to the weather were highlighted as the most unmanageable risk. Another significant barrier to mitigating environmental impacts emerged from the lack of options towards choosing appropriate fields in which to conduct outwintering. We argue that the farmer-led nature of outwintering and the development of a wide range of systems is evidence of outwintering being a systems-innovation. We conclude that there is a role for Government intervention through the provision of information which clarifies cross-compliance breaches, but also encourages farmer-led innovation to develop more responsive outwintering systems.


Asunto(s)
Agricultura/métodos , Bovinos , Toma de Decisiones , Ambiente , Percepción , Animales , Industria Lechera/métodos , Inglaterra , Medición de Riesgo , Encuestas y Cuestionarios , Gales
3.
J Environ Manage ; 110: 226-35, 2012 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-22805711

RESUMEN

Perception-based typologies have been used to explore the decision making process of farmers and to inform policy design. These typologies have been criticised, however, for not fully capturing true farmer behaviour, and are consequently limited for supporting policy formulation. We present a method that develops a typology, using a social survey approach based on how farmers perceive their environment (e.g. birds and agri-environmental schemes). We then apply time-series census data on past farm strategies (i.e. land use allocation, management style and participation into agri-environmental schemes) to refine these typologies. Consequently, this offers an approach to improving the profiling of farmer types, and strengthens the validity of input into future agricultural policies. While the social survey highlights a certain degree of awareness towards birds with respect to farmer types, the analysis of past farm strategies indicated that farmers did not entirely follow their stated objectives. External factors such as input and output price signals and subsidy levels had a stronger influence on their strategies rather than stated environmental and social issues. Consequently, the refining of farmer types using this approach would aid the design of policy instruments, which integrate ecological issues within planning.


Asunto(s)
Agricultura/economía , Actitud , Censos , Conservación de los Recursos Naturales , Animales , Aves , Toma de Decisiones , Ambiente , Política Ambiental , Escocia
4.
J Dairy Sci ; 94(11): 5449-57, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22032367

RESUMEN

A key indicator of resource use within farming is technical efficiency, which measures the amount of physical output attainable from a given set of inputs. The social aspects, in particular the treatment of animals, have generally been ignored within these measurement schemas. In addition, animal welfare will affect the production technology under which farms operate, and some allowance for this is needed within the measurement approach. This is the first paper to apply animal welfare as a discriminating technology within a technical efficiency framework. Using results from an animal welfare monitoring study coupled with resource usage data, it presents an adjusted measure of technical efficiency applied to a sample of British dairy farms and compares differences in lameness management strategies for herds. We employ both a categorical and nondiscretionary variant of the data envelopment analysis approach to measure technical efficiencies and adjust for various degrees of lameness prevalence among these farms. This paper finds that farms with low rates of lameness (below 10% of the cattle herd) tend to have significantly higher technical efficiencies than those with lameness rates of above 10% of the herd. Farms that have levels of lameness of between 10 to 20% of the herd and higher levels of lameness (above 20% of the herd) did not differ significantly. Furthermore, low lameness farms are inefficient in terms of labor and stocking density, but this is outweighed by the gain in milk yield obtained on these farms. Consequently, we argue for a whole-farm, rather than a partial indicator, approach to assessing efficiency when noneconomic factors such as lameness are accounted for. From a policy perspective, we support programs that encourage active lameness management.


Asunto(s)
Enfermedades de los Bovinos/epidemiología , Industria Lechera/métodos , Industria Lechera/normas , Eficiencia , Cojera Animal/epidemiología , Bienestar del Animal , Animales , Bovinos
5.
J Environ Manage ; 90(2): 808-14, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18343559

RESUMEN

Managing diffuse water pollution from agricultural land continues to be one of the more intractable challenges for environmental policy. The advent of the Water Framework Directive places the onus on EU member states to identify reasons why water bodies fail or are at risk of failure to meet good ecological status. In such cases, programmes of measures are to be enacted to mitigate the causes at least cost. Failing this, users may ultimately be faced with the full costs of pollution. This paper considers the scope for measures that address nitrogen and phosphorus pollution at source. Specifically the paper relates the diffuse pollution problem to the extent of over application of nitrogen and phosphorus. Data envelopment analysis applied to English cereal and dairy farmers, provides an indication of resource use and evidence of over application. This inefficiency provides a potential basis for either a least cost abatement approach using effective information and advice, or alternatively a pollution charge.


Asunto(s)
Agricultura/legislación & jurisprudencia , Reino Unido , Contaminación del Agua
6.
J Environ Manage ; 80(4): 287-94, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16549233

RESUMEN

Recent policy changes within the Common Agricultural Policy have led to a shift from a solely production-led agriculture towards the promotion of multi-functionality. Conversely, the removal of production-led supports would indicate that an increased concentration on production efficiencies would seem a critical strategy for a country's future competitiveness. This paper explores the relationship between the 'multi-functional' farming attitude desired by policy makers and its effect on technical efficiency within Scottish dairy farming. Technical efficiency scores are calculated by applying the non-parametric data envelopment analysis technique and then measured against causes of inefficiency. Amongst these explanatory factors is a constructed score of multi-functionality. This research finds that, amongst other factors, a multi-functional attitude has a significant positive effect on technical efficiency. Consequently, this seems to validate the promotion of a multi-functional approach to farming currently being championed by policy-makers.


Asunto(s)
Productos Lácteos , Industria de Alimentos/métodos , Industria de Alimentos/estadística & datos numéricos , Productos Lácteos/estadística & datos numéricos , Escocia , Estadísticas no Paramétricas
7.
J Mol Biol ; 302(1): 17-25, 2000 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-10964558

RESUMEN

SINEs, short interspersed repeated DNA elements, undergo amplification through retroposition and subsequent integration into a new location in the genome. Each new SINE insertion will be located in a new chromosomal environment, with different flanking sequences. Modulation of transcription by different flanking sequences may play an important role in determining which SINE elements are preferentially active in a genome. We evaluated the ability of upstream flanking sequences to regulate the transcription of three different SINEs (Alu, B2 and ID) by constructing chimeric constructs with known 5' flanking sequences of RNA polymerase III-transcribed genes. Upstream sequences from the 7SL RNA gene, U6 RNA gene, vault RNA gene, and BC1 gene increase transcription of Alu, B2 and BC1 in transient transfections of NIH3T3, HeLa, Neuro2a and C6 glioma cell lines. The 7SL sequence proved most efficient in increasing SINE transcription. The 7SL upstream fused to the BC1 RNA gene (an ID element) was used to create a transgenic mouse line. In contrast to the tissue-specific endogenous BC1 transcription, BC1 transgene transcripts were detected in all tissues tested. However, expression was much higher in those tissues that express the endogenous gene, demonstrating both transcriptional and post-transcriptional regulation. The BC1 RNA was detected in a similar ribonucleoprotein complex in the different tissues.


Asunto(s)
Regulación de la Expresión Génica/genética , Secuencias Reguladoras de Ácidos Nucleicos/genética , Elementos de Nucleótido Esparcido Corto/genética , Transcripción Genética/genética , Elementos Alu/genética , Animales , Línea Celular , ADN Recombinante/genética , Evolución Molecular , Perfilación de la Expresión Génica , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , ARN/biosíntesis , ARN/genética , ARN/metabolismo , ARN Polimerasa III/metabolismo , Retroelementos/genética , Ribonucleoproteínas/metabolismo , Transgenes/genética , Células Tumorales Cultivadas , Regulación hacia Arriba/genética
8.
J Neurophysiol ; 83(3): 1502-9, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10712475

RESUMEN

ATP has been suggested to act as a neurotransmitter or a neuromodulator in the cochlea. The responses to ATP in different cell types of the cochlea vary in terms of the rate of desensitization and magnitude, suggesting that there may be different subtypes of P2X receptors distributed in the cochlea. Recently three ionotropic P2X(2) receptor splice variants, P2X(2-1), P2X(2-2), and P2X(2-3,) were isolated and sequenced from a guinea pig cochlear cDNA library. To test the hypothesis that these different splice variants could be expressed as functional homomeric receptors, the three P2X(2) receptor variants were individually and transiently expressed in human embryonic kidney cells (HEK293). The biophysical and pharmacological properties of these receptors were characterized using the whole cell patch-clamp technique. Extracellular application of ATP induced an inward current in HEK293 cells containing each of the three splice variants in a dose-dependent manner indicating the expression of homomeric receptors. Current-voltage (I-V) relationships for the ATP-gated current show that the three subtypes of the P2X(2) receptor had a similar reversal potential and an inward rectification index (I(50 mV)/I(-50 mV)). However, the ATP-induced currents in cells expressing P2X(2-1) and P2X(2-2) variants were large and desensitized rapidly whereas the current in those cells expressing the P2X(2-3) variant was much smaller and desensitized slower. The order of potency to ATP agonists was 2-MeSATP > ATP > alpha,beta -MeATP for all three expressed splice variants. The ATP receptor antagonists suramin and PPADS reduced the effects of ATP on all three variants. Results demonstrate that three P2X(2) splice variants from guinea pig cochlea, P2X(2-1), P2X(2-2), and P2X(2-3), can individually form nonselective cation receptor channels when these subunits are expressed in HEK293 cells. The distinct properties of these P2X(2) receptor splice variants may contribute to the differences in the response to ATP observed in native cochlear cells.


Asunto(s)
Cóclea/metabolismo , Neuropéptidos/biosíntesis , Receptores Purinérgicos P2/biosíntesis , Adenosina Trifosfato/fisiología , Animales , Línea Celular , Electrofisiología , Cobayas , Humanos , Activación del Canal Iónico/fisiología , Riñón/metabolismo , Potenciales de la Membrana/fisiología , Neuropéptidos/genética , Técnicas de Placa-Clamp , Plásmidos/genética , Antagonistas del Receptor Purinérgico P2 , Fosfato de Piridoxal/análogos & derivados , Fosfato de Piridoxal/farmacología , Receptores Purinérgicos P2/genética , Receptores Purinérgicos P2X2 , Suramina/farmacología , Transfección
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