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1.
Nat Commun ; 10(1): 1481, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30931943

RESUMO

How insects promote crop pollination remains poorly understood in terms of the contribution of functional trait differences between species. We used meta-analyses to test for correlations between community abundance, species richness and functional trait metrics with oilseed rape yield, a globally important crop. While overall abundance is consistently important in predicting yield, functional divergence between species traits also showed a positive correlation. This result supports the complementarity hypothesis that pollination function is maintained by non-overlapping trait distributions. In artificially constructed communities (mesocosms), species richness is positively correlated with yield, although this effect is not seen under field conditions. As traits of the dominant species do not predict yield above that attributed to the effect of abundance alone, we find no evidence in support of the mass ratio hypothesis. Management practices increasing not just pollinator abundance, but also functional divergence, could benefit oilseed rape agriculture.


Assuntos
Biodiversidade , Brassica rapa , Produção Agrícola , Produtos Agrícolas , Insetos , Polinização , Animais
2.
PLoS One ; 11(5): e0153889, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27152628

RESUMO

Insect pollination underpins apple production but the extent to which different pollinator guilds supply this service, particularly across different apple varieties, is unknown. Such information is essential if appropriate orchard management practices are to be targeted and proportional to the potential benefits pollinator species may provide. Here we use a novel combination of pollinator effectiveness assays (floral visit effectiveness), orchard field surveys (flower visitation rate) and pollinator dependence manipulations (pollinator exclusion experiments) to quantify the supply of pollination services provided by four different pollinator guilds to the production of four commercial varieties of apple. We show that not all pollinators are equally effective at pollinating apples, with hoverflies being less effective than solitary bees and bumblebees, and the relative abundance of different pollinator guilds visiting apple flowers of different varieties varies significantly. Based on this, the taxa specific economic benefits to UK apple production have been established. The contribution of insect pollinators to the economic output in all varieties was estimated to be £92.1M across the UK, with contributions varying widely across taxa: solitary bees (£51.4M), honeybees (£21.4M), bumblebees (£18.6M) and hoverflies (£0.7M). This research highlights the differences in the economic benefits of four insect pollinator guilds to four major apple varieties in the UK. This information is essential to underpin appropriate investment in pollination services management and provides a model that can be used in other entomolophilous crops to improve our understanding of crop pollination ecology.


Assuntos
Insetos/classificação , Malus , Polinização , Animais , Insetos/fisiologia , Reino Unido
3.
J Agron Crop Sci ; 202(6): 508-517, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-29353966

RESUMO

Experiments were conducted over 2 years to quantify the response of faba bean (Vicia faba L.) to heat stress. Potted winter faba bean plants (cv. Wizard) were exposed to temperature treatments (18/10; 22/14; 26/18; 30/22; 34/26 °C day/night) for 5 days during floral development and anthesis. Developmental stages of all flowers were scored prior to stress, plants were grown in exclusion from insect pollinators to prevent pollen movement between flowers, and yield was harvested at an individual pod scale, enabling effects of heat stress to be investigated at a high resolution. Susceptibility to stress differed between floral stages; flowers were most affected during initial green-bud stages. Yield and pollen germination of flowers present before stress showed threshold relationships to stress, with lethal temperatures (t50) ˜28 °C and ~32 °C, while whole plant yield showed a linear negative relationship to stress with high plasticity in yield allocation, such that yield lost at lower nodes was partially compensated at higher nodal positions. Faba bean has many beneficial attributes for sustainable modern cropping systems but these results suggest that yield will be limited by projected climate change, necessitating the development of heat tolerant cultivars, or improved resilience by other mechanisms such as earlier flowering times.

4.
Agric Ecosyst Environ ; 184(100): 34-40, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24748698

RESUMO

Insect pollination is important for food production globally and apples are one of the major fruit crops which are reliant on this ecosystem service. It is fundamentally important that the full range of benefits of insect pollination to crop production are understood, if the costs of interventions aiming to enhance pollination are to be compared against the costs of the interventions themselves. Most previous studies have simply assessed the benefits of pollination to crop yield and ignored quality benefits and how these translate through to economic values. In the present study we examine the influence of insect pollination services on farmgate output of two important UK apple varieties; Gala and Cox. Using field experiments, we quantify the influence of insect pollination on yield and importantly quality and whether either may be limited by sub-optimal insect pollination. Using an expanded bioeconomic model we value insect pollination to UK apple production and establish the potential for improvement through pollination service management. We show that insects are essential in the production of both varieties of apple in the UK and contribute a total of £36.7 million per annum, over £6 million more than the value calculated using more conventional dependence ratio methods. Insect pollination not only affects the quantity of production but can also have marked impacts on the quality of apples, influencing size, shape and effecting their classification for market. These effects are variety specific however. Due to the influence of pollination on both yield and quality in Gala, there is potential for insect pollination services to improve UK output by up to £5.7 million per annum. Our research shows that continued pollinator decline could have serious financial implications for the apple industry but there is considerable scope through management of wild pollinators or using managed pollinator augmentation, to improve the quality of production. Furthermore, we show that it is critically important to consider all production parameters including quality, varietal differences and management costs when valuing the pollination service of any crop so investment in pollinator management can be proportional to its contribution.

5.
Biol Conserv ; 169(100): 128-135, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24696525

RESUMO

Insect pollinated mass flowering crops are becoming more widespread and there is a need to understand which insects are primarily responsible for the pollination of these crops so conservation measures can be appropriately targeted in the face of pollinator declines. This study used field surveys in conjunction with cage manipulations to identify the relative contributions of different pollinator taxa to the pollination of two widespread flowering crops, field beans and oilseed rape. Flower visiting pollinator communities observed in the field were distinct for each crop; while field beans were visited primarily by a few bumblebee species, multiple pollinator taxa visited oilseed, and the composition of this pollinator community was highly variable spatially and temporally. Neither pollinator community, however, appears to be meeting the demands of crops in our study regions. Cage manipulations showed that multiple taxa can effectively pollinate both oilseed and field beans, but bumblebees are particularly effective bean pollinators. Combining field observations and cage manipulations demonstrated that the pollination demands of these two mass flowering crops are highly contrasting, one would benefit from management to increase the abundance of some key taxa, whilst for the other, boosting overall pollinator abundance and diversity would be more appropriate. Our findings highlight the need for crop specific mitigation strategies that are targeted at conserving specific pollinator taxa (or group of taxa) that are both active and capable of crop pollination in order to reduce pollination deficits and meet the demands of future crop production.

6.
Biodivers Conserv ; 23: 1193-1214, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24719520

RESUMO

Pollination services provided by insects play a key role in English crop production and wider ecology. Despite growing evidence of the negative effects of habitat loss on pollinator populations, limited policy support is available to reverse this pressure. One measure that may provide beneficial habitat to pollinators is England's entry level stewardship agri-environment scheme. This study uses a novel expert survey to develop weights for a range of models which adjust the balance of Entry Level Stewardship options within the current area of spending. The annual costs of establishing and maintaining these option compositions were estimated at £59.3-£12.4 M above current expenditure. Although this produced substantial reduction in private cost:benefit ratios, the benefits of the scheme to pollinator habitat rose by 7-140 %; significantly increasing the public cost:benefit ratio. This study demonstrates that the scheme has significant untapped potential to provide good quality habitat for pollinators across England, even within existing expenditure. The findings should open debate on the costs and benefits of specific entry level stewardship management options and how these can be enhanced to benefit both participants and biodiversity more equitably.

7.
Environ Monit Assess ; 164(1-4): 337-48, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19365607

RESUMO

The field site network (FSN) plays a central role in conducting joint research within all Assessing Large-scale Risks for biodiversity with tested Methods (ALARM) modules and provides a mechanism for integrating research on different topics in ALARM on the same site for measuring multiple impacts on biodiversity. The network covers most European climates and biogeographic regions, from Mediterranean through central European and boreal to subarctic. The project links databases with the European-wide field site network FSN, including geographic information system (GIS)-based information to characterise the test location for ALARM researchers for joint on-site research. Maps are provided in a standardised way and merged with other site-specific information. The application of GIS for these field sites and the information management promotes the use of the FSN for research and to disseminate the results. We conclude that ALARM FSN sites together with other research sites in Europe jointly could be used as a future backbone for research proposals.


Assuntos
Biodiversidade , Europa (Continente) , Medição de Risco
8.
J R Coll Physicians Edinb ; 39(4): 331-6, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21152475

RESUMO

Transplant units increasingly recognise a need for assistance from psychiatrists and psychologists in the assessment and management of potential transplant recipients and live donors. This arises from the various known associations between mental disorder and the need for transplantation; the intensifying requirement to select carefully among the potential recipients and donors of scarce human organs; and the drive to maximise transplant outcomes by optimising all aspects of treatment after surgery. There is good evidence that careful, protocol-guided selection among potential candidates for transplantation with alcoholic liver disease helps ensure outcomes at least as good as for other forms of liver disease. The evidence base in other areas is less robust, but the principles guiding the psychiatric assessment are broadly the same. There is an increasing need for psychiatric assessment of potential live organ donors, in order to minimise the risks they run, and in the case of altruistic donation this is now mandatory in UK law.

9.
Scott Med J ; 53(2): 15-7, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18549064

RESUMO

BACKGROUND: Clinical experience suggests that non-psychiatrists' knowledge of mental health legislation in relation to emergency detention is inadequate. However, most non-psychiatrists will use this legislation at some point in their career. METHODOLOGY: A questionnaire about emergency detention legislation was circulated to non-psychiatric medical staff to test their knowledge of the provisions relevant to the general hospital. RESULTS: Two hundred and seventy four medical staff replied (a response rate of 82%). Results showed that an understanding of detention procedures and applicability were markedly deficient, irrespective of grade, specialty or experience. CONCLUSION: The results indicate a need for increased education and awareness about emergency detention legislation especially in view of the implementation of the Mental Health (Scotland) Act (2003).


Assuntos
Competência Clínica , Hospitais Gerais , Serviços de Saúde Mental/legislação & jurisprudência , Internação Compulsória de Doente Mental/legislação & jurisprudência , Serviços Médicos de Emergência , Hospitais Psiquiátricos/legislação & jurisprudência , Humanos , Médicos , Padrões de Prática Médica/legislação & jurisprudência , Escócia , Inquéritos e Questionários
10.
Science ; 313(5785): 351-4, 2006 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-16857940

RESUMO

Despite widespread concern about declines in pollination services, little is known about the patterns of change in most pollinator assemblages. By studying bee and hoverfly assemblages in Britain and the Netherlands, we found evidence of declines (pre-versus post-1980) in local bee diversity in both countries; however, divergent trends were observed in hoverflies. Depending on the assemblage and location, pollinator declines were most frequent in habitat and flower specialists, in univoltine species, and/or in nonmigrants. In conjunction with this evidence, outcrossing plant species that are reliant on the declining pollinators have themselves declined relative to other plant species. Taken together, these findings strongly suggest a causal connection between local extinctions of functionally linked plant and pollinator species.


Assuntos
Abelhas , Biodiversidade , Dípteros , Ecossistema , Plantas , Pólen , Migração Animal , Animais , Meio Ambiente , Flores , Países Baixos , Dinâmica Populacional , Reino Unido
11.
QJM ; 92(2): 81-6, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10209659

RESUMO

We used a psychological treatment package (education, relaxation, breathing training, graded exposure to activity and exercise, and challenging automatic thoughts about heart disease) to treat 60 patients who had continuing chest pain despite cardiological reassurance following haemodynamically normal angiography. The treatment was delivered in six sessions over eight weeks to groups of up to six patients. The patients kept daily records of chest pain episode frequency and nitrate use. Questionnaires were used to assess anxiety, depression and disability. Exercise tolerance was tested by treadmill electrocardiography, with capnographic assessment of hyperventilation. The results were compared with waiting-list controls. Treatment significantly reduced chest pain episodes (p < 0.01) from median 6.5 to 2.5 per week. There were significant improvements in anxiety and depression scores (p < 0.05), disability rating (p < 0.0001) and exercise tolerance (p < 0.05), and these were maintained at six month follow-up. Treatment reduced the prevalence of hyperventilation from 54% to 34% (p < 0.01) but not the prevalence of ECG-positive exercise tests. Patients continuing to attribute their pain to heart disease had poorer outcomes. Group psychological treatment for non-cardiac chest pain is feasible, reduces pain, psychological morbidity and disability, and improves exercise tolerance.


Assuntos
Dor no Peito/terapia , Psicoterapia de Grupo/métodos , Exercícios Respiratórios , Terapia por Exercício/métodos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Terapia de Relaxamento
12.
Br J Sports Med ; 33(1): 19-21, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10027052

RESUMO

OBJECTIVES: To examine the illness attitudes and beliefs known to be associated with abnormal illness behaviour (where symptoms are present in excess of objective signs and pathology) in elite middle and long distance runners, in comparison with non-athlete controls. METHODS: A total of 150 athletes were surveyed using the illness behaviour questionnaire as an instrument to explore the psychological attributes associated with abnormal illness behaviour. Subjects also completed the general health questionnaire as a measure of psychiatric morbidity. A control group of 150 subjects, matched for age, sex, and social class, were surveyed using the same instruments. RESULTS: A multivariate analysis of illness behaviour questionnaire responses showed that the athletes' group differed significantly from the control group (Hotelling's T: Exact F = 2.68; p = 0.01). In particular, athletes were more somatically focused (difference between means -0.27; 95% confidence interval -0.50 to -0.03) and more likely to deny the impact of stresses in their life (difference between means 0.78; 95% confidence interval 0.31 to 1.25). Athletes were also higher scorers on the Whiteley Index of Hypochondriasis (difference between means 0.76; 95% confidence interval 0.04 to 1.48). There were no differences in the levels of psychiatric morbidity between the two groups. CONCLUSIONS: The illness attitudes and beliefs of athletes differ from those of a well matched control population. The origin of these psychological attributes is not clear but those who treat athletes need to be aware of them.


Assuntos
Corrida/psicologia , Papel do Doente , Transtornos Somatoformes/epidemiologia , Adulto , Estudos de Casos e Controles , Coleta de Dados , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Incidência , Masculino , Análise Multivariada , Valores de Referência , Transtornos Somatoformes/diagnóstico , Transtornos Somatoformes/fisiopatologia , Reino Unido/epidemiologia
13.
Psychol Med ; 25(2): 339-47, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7675922

RESUMO

Forty-six patients with chest pain but normal or near-normal coronary arteries were assessed using standardized interviews and rating scales at the time of angiography, after 1 year, and again 11.4 years later. Psychological morbidity was substantial and enduring: 61% of patients were designated as psychiatric cases at angiography and 49% at 11.4 years. Both at the time of angiography, and 1 year later, levels of morbidity were significantly greater than in a control group of 53 patients with coronary artery disease. Anxiety disorders were common at all three interviews, with panic disorder (15% of patients) the most common current diagnosis at final follow-up. Current somatoform disorders were diagnosed in 9 patients (22%), and 11 (27%) reported previous episodes of major depression. Psychological morbidity was associated with continuing chest pain, which was reported in 74% of patients, and with ongoing functional incapacity. These findings suggest that, in a sub-group of these patients, psychological factors contribute in part to the development of chest pain and other physical symptoms, and are also important in maintaining the disorder over long periods. Further research is now required to identify more fully the nature of these psychological factors, and how they interact with cardiac and non-cardiac physical pathology. There is also an urgent need to examine the clinical and economic benefits of specific psychological interventions.


Assuntos
Dor no Peito/psicologia , Astenia Neurocirculatória/psicologia , Transtornos Somatoformes/psicologia , Adulto , Transtornos de Ansiedade/diagnóstico , Transtornos de Ansiedade/psicologia , Dor no Peito/diagnóstico , Angiografia Coronária , Doença das Coronárias/diagnóstico , Doença das Coronárias/psicologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Astenia Neurocirculatória/diagnóstico , Transtorno de Pânico/diagnóstico , Transtorno de Pânico/psicologia , Determinação da Personalidade , Transtornos Somatoformes/diagnóstico
15.
Q J Med ; 86(9): 583-93, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8255973

RESUMO

Forty-six patients who were investigated in 1979-80 for chest pain, and found to have normal or insignificantly narrowed coronary arteries on coronary angiography, were followed up after a mean interval of 11.4 years. Patients were interviewed and given standardized questionnaires covering chest pain and other physical symptoms, psychiatric morbidity, and functional capacity. Medical records for the follow-up period were reviewed, as were death certificates and post-mortem reports, where appropriate. All patients (100%) were traced to death or their current address. Four had died (11.4 year survival rate 91%), one from ischaemic heart disease. Continuing chest pain was reported by 74%, and in 16 patients (38%), chest pain was either frequent, severe or both. A poor outcome for chest pain was associated with other physical symptoms and increased psychiatric morbidity, which for the entire cohort was higher than at 1 year after angiography. Twenty-six patients (58%) had received further hospital treatment for chest pain, including, in six patients, further coronary angiography. Twenty-nine survivors (71%) were taking cardiac medication, 12 (29%) were unable to work for medical reasons, and levels of functional disability were similar to those found in patients with myocardial infarction or angina. This study confirms the findings of previous studies with shorter follow-up intervals. Mortality was low, but high levels of chest pain, psychological distress, and functional incapacity persisted long after angiography. Patients reported many physical symptoms other than chest pain, and had made heavy use of medical resources. For many patients, reassurance after angiography had been ineffective, and the prognosis was poor. Early identification and effective management of such patients could offer the NHS substantial savings.


Assuntos
Dor no Peito/psicologia , Adulto , Atitude Frente a Saúde , Dor no Peito/diagnóstico por imagem , Dor no Peito/mortalidade , Angiografia Coronária , Pessoas com Deficiência , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Morbidade , Aceitação pelo Paciente de Cuidados de Saúde , Prognóstico , Recidiva , Estresse Psicológico
19.
Behav Neurol ; 5(1): 19-22, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-24487656

RESUMO

A case is reported of lithium intoxication presenting with a mixed misidentification syndrome including features of Capgras syndrome. CT scanning showed cerebral atrophy, greater on the right, consistent with earlier evidence, suggesting that misidentification syndromes are more common with right hemisphere lesions.

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