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3.
Ecol Appl ; 31(8): e02431, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34339067

RESUMO

Implementation of wildfire- and climate-adaptation strategies in seasonally dry forests of western North America is impeded by numerous constraints and uncertainties. After more than a century of resource and land use change, some question the need for proactive management, particularly given novel social, ecological, and climatic conditions. To address this question, we first provide a framework for assessing changes in landscape conditions and fire regimes. Using this framework, we then evaluate evidence of change in contemporary conditions relative to those maintained by active fire regimes, i.e., those uninterrupted by a century or more of human-induced fire exclusion. The cumulative results of more than a century of research document a persistent and substantial fire deficit and widespread alterations to ecological structures and functions. These changes are not necessarily apparent at all spatial scales or in all dimensions of fire regimes and forest and nonforest conditions. Nonetheless, loss of the once abundant influence of low- and moderate-severity fires suggests that even the least fire-prone ecosystems may be affected by alteration of the surrounding landscape and, consequently, ecosystem functions. Vegetation spatial patterns in fire-excluded forested landscapes no longer reflect the heterogeneity maintained by interacting fires of active fire regimes. Live and dead vegetation (surface and canopy fuels) is generally more abundant and continuous than before European colonization. As a result, current conditions are more vulnerable to the direct and indirect effects of seasonal and episodic increases in drought and fire, especially under a rapidly warming climate. Long-term fire exclusion and contemporaneous social-ecological influences continue to extensively modify seasonally dry forested landscapes. Management that realigns or adapts fire-excluded conditions to seasonal and episodic increases in drought and fire can moderate ecosystem transitions as forests and human communities adapt to changing climatic and disturbance regimes. As adaptation strategies are developed, evaluated, and implemented, objective scientific evaluation of ongoing research and monitoring can aid differentiation of warranted and unwarranted uncertainties.


Assuntos
Incêndios , Incêndios Florestais , Ecossistema , Florestas , Humanos , América do Norte
4.
Ann R Coll Surg Engl ; 103(7): 514-519, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34192490

RESUMO

INTRODUCTION: The aims of this study were threefold: first, to review the surgical performance of trainees in our departments by reviewing postoperative radiographs and operative times; second, to investigate the effect of supervision and assistant grade on postoperative radiographs and operative times; and third, to monitor trainees over a 6-month period looking for changes in postoperative radiograph appearances and operative times to assess whether these parameters reflect a trainee's learning curve. METHODS: A retrospective evaluation of a continuous series of primary hip arthroplasty procedures performed by 12 trainee orthopaedic surgeons (StR) during their arthroplasty rotation. In total, 348 primary total hip replacement (pTHR) operations were performed by StRs. Operative time, acetabular cup inclination, radiological leg length discrepancy (rLLD), femoral stem alignment (FSA) and the Barrack score for cementation were evaluated. The mean number of pTHRs performed per 6-month placement was 29 (range 15-51). Operative times were available for 292 cases and all postoperative imaging was evaluated. RESULTS: The mean operative time for StRs as first-surgeon was 84.3 minutes (range 42-174 minutes). Significant differences in operative times were observed between individual StRs. As a cohort, the operative times were not affected by the level of supervision but were significantly slower when StRs were assisted by other StRs. Significant differences in rLLD, FSA and Barrack score for cementation were observed across the cohort of StRs, although this did not change at a group or individual level between the first and second halves of the 6-month placement. CONCLUSIONS: Used in isolation, postoperative radiographs and operative time are not an effective measure of the learning curve in primary hip arthroplasty, however, they may be a useful adjunct in assessing the performance of orthopaedic trainees when learning primary hip arthroplasty.


Assuntos
Artroplastia de Quadril/educação , Competência Clínica/estatística & dados numéricos , Curva de Aprendizado , Cirurgiões Ortopédicos/estatística & dados numéricos , Osteoartrite do Quadril/cirurgia , Artroplastia de Quadril/estatística & dados numéricos , Competência Clínica/normas , Articulação do Quadril/diagnóstico por imagem , Articulação do Quadril/cirurgia , Humanos , Internato e Residência/estatística & dados numéricos , Duração da Cirurgia , Cirurgiões Ortopédicos/educação , Cirurgiões Ortopédicos/normas , Período Pós-Operatório , Estudos Retrospectivos , Resultado do Tratamento
5.
Anim Cogn ; 24(3): 457-470, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33113033

RESUMO

Although several nonhuman animals have the ability to recognize and match templates in computerized tasks, we know little about their ability to recall and then physically manufacture specific features of mental templates. Across three experiments, Goffin cockatoos (Cacatua goffiniana), a species that can use tools in captivity, were exposed to two pre-made template objects, varying in either colour, size (long or short) or shape (I or L-shaped), where only one template was rewarded. Birds were then given the opportunity to manufacture versions of these objects themselves. We found that all birds carved paper strips from the same colour material as the rewarded template, and half were also able to match the size of a template (long and short). This occurred despite the template being absent at test and birds being rewarded at random. However, we found no evidence that cockatoos could carve L-shaped pieces after learning that L-shaped templates were rewarded, though their manufactured strips were wider than in previous tests. Overall, our results show that Goffin cockatoos possess the ability to physically adjust at least the size dimension of manufactured objects relative to a mental template. This ability has previously only been shown in New Caledonian crows, where template matching was suggested as a potential mechanism allowing for the cumulative cultural transmission of tool designs. Our results show that within avian tool users, the ability to recreate a physical template from memory does not seem to be restricted to species that have cumulative tool cultures.


Assuntos
Cacatuas , Papagaios , Animais , Aprendizagem , Memória , Recompensa
6.
Proc Biol Sci ; 287(1938): 20201490, 2020 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-33143583

RESUMO

The ability to plan for future events is one of the defining features of human intelligence. Whether non-human animals can plan for specific future situations remains contentious: despite a sustained research effort over the last two decades, there is still no consensus on this question. Here, we show that New Caledonian crows can use tools to plan for specific future events. Crows learned a temporal sequence where they were (a) shown a baited apparatus, (b) 5 min later given a choice of five objects and (c) 10 min later given access to the apparatus. At test, these crows were presented with one of two tool-apparatus combinations. For each combination, the crows chose the right tool for the right future task, while ignoring previously useful tools and a low-value food item. This study establishes that planning for specific future tool use can evolve via convergent evolution, given that corvids and humans shared a common ancestor over 300 million years ago, and offers a route to mapping the planning capacities of animals.


Assuntos
Corvos , Comportamento de Utilização de Ferramentas , Animais , Nova Caledônia
7.
Ment Health Phys Act ; 19: 100360, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33020704

RESUMO

The aim of this review is to systematically describe and quantify the effects of PA interventions on alcohol and other drug use outcomes, and to identify any apparent effect of PA dose and type, possible mechanisms of effect, and any other aspect of intervention delivery (e.g. key behaviour change processes), within a framework to inform the design and evaluation of future interventions. Systematic searches were designed to identify published and grey literature on the role of PA for reducing the risk of progression to alcohol and other drug use (PREVENTION), supporting individuals to reduce alcohol and other drug use for harm reduction (REDUCTION), and promote abstinence and relapse prevention during and after treatment of alcohol and other drug use (TREATMENT). Searches identified 49,518 records, with 49,342 excluded on title and abstract. We screened 176 full text articles from which we included 32 studies in 32 papers with quantitative results of relevance to this review. Meta-analysis of two studies showed a significant effect of PA on prevention of alcohol initiation (risk ratio [RR]: 0.72, 95%CI: 0.61 to 0.85). Meta-analysis of four studies showed no clear evidence for an effect of PA on alcohol consumption (Standardised Mean Difference [SMD]: 0.19, 95%, Confidence Interval -0.57 to 0.18). We were unable to quantitatively examine the effects of PA interventions on other drug use alone, or in combination with alcohol use, for prevention, reduction or treatment. Among the 19 treatment studies with an alcohol and other drug use outcome, there was a trend for promising short-term effect but with limited information about intervention fidelity and exercise dose, there was a moderate to high risk of bias. We identified no studies reporting the cost-effectiveness of interventions. More rigorous and well-designed research is needed. Our novel approach to the review provides a clearer guide to achieve this in future research questions addressed to inform policy and practice for different populations and settings.

8.
Anaesthesia ; 75(4): 479-486, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32037522

RESUMO

Cell salvage is an important component of blood management in patients undergoing revision hip arthroplasty surgery. However concerns regarding efficacy and patient selection remain. The aims of this study were to describe intra-operative blood loss, cell salvage re-infusion volumes and red blood cell transfusion rates for revision hip procedures and to identify factors associated with the ability to salvage sufficient blood intra-operatively to permit processing and re-infusion. Data were collected from a prospective cohort of 664 consecutive patients undergoing revision hip surgery at a single tertiary centre from 31 March 2015 to 1 April 2018. Indications for revision surgery were aseptic (n = 393 (59%)) fracture (n = 160 (24%)) and infection (n = 111 (17%)). Salvaged blood was processed and re-infused when blood loss exceeded 500 ml. Mean (SD) intra-operative blood loss was 1038 (778) ml across all procedures. Salvaged blood was re-infused in 505 of 664 (76%) patients. Mean (SD) re-infusion volume was 253 (169) ml. In total, 246 of 664 (37%) patients received an allogeneic red blood cell transfusion within 72 h of surgery. Patients undergoing femoral component revision only (OR (95%CI) 0.41 (0.23-0.73)) or acetabular component revision only (0.53 (0.32-0.87)) were less likely to generate sufficient blood salvage volume for re-infusion compared with revision of both components. Compared with aseptic indications, patients undergoing revision surgery for infection (1.87 (1.04-3.36)) or fracture (4.43 (2.30-8.55)) were more likely to generate sufficient blood salvage volume for re-infusion. Our data suggest that cell salvage is efficacious in this population. Cases where the indication is infection or fracture and where both femoral and acetabular components are to be revised should be prioritised.


Assuntos
Artroplastia de Quadril/métodos , Transfusão de Sangue Autóloga/métodos , Cuidados Intraoperatórios/métodos , Recuperação de Sangue Operatório/métodos , Reoperação/métodos , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
9.
Artigo em Inglês | MEDLINE | ID: mdl-31618675

RESUMO

OBJECTIVE: To determine if plasma concentrations of the N-acylethanolamines (NAEs) N-arachidonoylethanolamine (AEA), N-oleoylethanolamide (OEA) and N-palmitoylethanolamide (PEA) increase in women at high risk for preterm birth (PTB) and whether these could be used to predict preterm delivery and if so, how they compare with current methods. DESIGN: Prospective cohort study. SETTING: A large UK teaching hospital. POPULATION: 217 pregnant women were recruited between 24 and 34 gestational weeks at 'high-risk' for PTB, recruited from a prematurity prevention clinic or antenatal wards. METHODS: Plasma AEA, OEA, and PEA concentrations were measured using ultra-high performance liquid chromatography-tandem mass spectrometry whilst FAAH enzyme activity was measured by fluorometric radiometric assay and CL by ultrasound scan. The clinical usefulness of these measurements were determined by ROC and multivariate analyses. RESULTS: AEA and PEA concentrations were significantly higher in women who delivered prematurely. An AEA concentration >1.095 nM predicted PTB, the gestational age at delivery and the recruitment to delivery interval (RTDI). A PEA concentration >17.50 nM only predicted PTB; FAAH enzyme activity was not related to these changes. Multivariate analysis (all variables) generated an equation to accurately predict the RTDI. CONCLUSIONS: A single plasma AEA or PEA measurement can predict PTB. A single AEA measurement predicts the gestational age of delivery and the remaining period of pregnancy with reasonable accuracy and better than existing conventional tests thus offering a better window for primary prevention of PTB.


Assuntos
Endocanabinoides/sangue , Etanolaminas/sangue , Idade Gestacional , Trabalho de Parto Prematuro/sangue , Ácidos Oleicos/sangue , Ácidos Palmíticos/sangue , Nascimento Prematuro/sangue , Amidas , Amidoidrolases/sangue , Ácidos Araquidônicos , Estudos de Coortes , Feminino , Humanos , Trabalho de Parto Prematuro/epidemiologia , Alcamidas Poli-Insaturadas , Gravidez , Nascimento Prematuro/epidemiologia , Estudos Prospectivos , Medição de Risco , Reino Unido
10.
Sci Rep ; 9(1): 4151, 2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-30842442

RESUMO

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

11.
Sci Rep ; 8(1): 8956, 2018 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-29955154

RESUMO

Cumulative cultural evolution occurs when social traditions accumulate improvements over time. In humans cumulative cultural evolution is thought to depend on a unique suite of cognitive abilities, including teaching, language and imitation. Tool-making New Caledonian crows show some hallmarks of cumulative culture; but this claim is contentious, in part because these birds do not appear to imitate. One alternative hypothesis is that crows' tool designs could be culturally transmitted through a process of mental template matching. That is, individuals could use or observe conspecifics' tools, form a mental template of a particular tool design, and then reproduce this in their own manufacture - a process analogous to birdsong learning. Here, we provide the first evidence supporting this hypothesis, by demonstrating that New Caledonian crows have the cognitive capacity for mental template matching. Using a novel manufacture paradigm, crows were first trained to drop paper into a vending machine to retrieve rewards. They later learnt that only items of a particular size (large or small templates) were rewarded. At test, despite being rewarded at random, and with no physical templates present, crows manufactured items that were more similar in size to previously rewarded, than unrewarded, templates. Our results provide the first evidence that this cognitive ability may underpin the transmission of New Caledonian crows' natural tool designs.


Assuntos
Corvos/fisiologia , Memória de Curto Prazo/fisiologia , Comportamento de Utilização de Ferramentas/fisiologia , Animais , Evolução Biológica , Cognição/fisiologia , Feminino , Distribuidores Automáticos de Alimentos , Comportamento Imitativo/fisiologia , Testes de Inteligência , Masculino , Recompensa , Estatísticas não Paramétricas
12.
Bone Joint J ; 99-B(5): 614-622, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28455470

RESUMO

AIMS: Advocates of debridement, antibiotics and implant retention (DAIR) in hip periprosthetic joint infection (PJI) argue that a procedure not disturbing a sound prosthesis-bone interface is likely to lead to better survival and functional outcome compared with revision. This case-control study aims were to compare outcome of DAIRs for infected primary total hip arthroplasty (THA) with outcomes following primary THA and two-stage revision of infected primary THAs. PATIENTS AND METHODS: We retrospectively reviewed all DAIRs, performed for confirmed infected primary hip arthropasty (n = 82) at out institution, between 1997 and 2013. Data recorded included full patient information and type of surgery. Outcome measures included complications, mortality, implant survivorship and functional outcome. Outcome was compared with two control groups matched for gender and age; a cohort of primary THAs (n = 120) and a cohort of two-stage revisions for infection (n = 66). RESULTS: Mean age at DAIR was 69 years (33 to 87) and mean follow-up was eight years (2 to 17; standard deviation (sd) 5). A total of 52 (63%) of DAIRs were for early PJI (less than six weeks). Greater success in the eradication of infection with DAIR was identified with early PJI, comprising an interval less than a week between onset of symptoms and exchange of modular components with the DAIR procedure. Eradication of infection, complications and re-operation rates were similar in the DAIR and two-stage revision groups. For hips with successful eradication of infection with DAIR, the five-year survival (98%; 95% confidence interval (CI) 94 to 100) was similar to the primary THA group (98%; 95% CI 95 to 100) (n = 43; p = 0.3). The DAIR group had inferior mean Oxford Hip Scores (OHS) (38; 12 to 48) compared with the primary THA group (42; 15 to 48) (p = 0.02) but a significantly better mean OHS compared with the two-stage revision group (31; 0 to 48) (p = 0.008). Patients who required only one DAIR for eradication of infection had a similar mean OHS (41; 20 to 48) to the primary THA group (p = 0.2). CONCLUSION: The DAIR procedure is associated with a similar complication rate and ability to eradicate infection as two-stage revision. This study emphasises the need for exchange of modular components for improved chances of eradication of infection. This is the first study showing that DAIR is better than a two-stage revision regarding functional outcome. Cite this article: Bone Joint J 2017;99-B:614-22.


Assuntos
Antibacterianos/uso terapêutico , Artroplastia de Quadril/métodos , Desbridamento/métodos , Prótese de Quadril/efeitos adversos , Infecções Relacionadas à Prótese/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Artroplastia de Quadril/instrumentação , Estudos de Casos e Controles , Terapia Combinada , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Reoperação/métodos , Estudos Retrospectivos , Resultado do Tratamento
13.
PLoS One ; 11(12): e0167419, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27973610

RESUMO

It is highly difficult to pinpoint what is going through an animal's mind when it appears to solve a problem by 'insight'. Here, we searched for an information processing error during the emergence of seemingly insightful stone dropping in New Caledonian crows. We presented these birds with the platform apparatus, where a heavy object needs to be dropped down a tube and onto a platform in order to trigger the release of food. Our results show New Caledonian crows exhibit a weight inattention error: they do not attend to the weight of an object when innovating stone dropping. This suggests that these crows do not use an understanding of force when solving the platform task in a seemingly insightful manner. Our findings showcase the power of the signature-testing approach, where experiments search for information processing biases, errors and limits, in order to make strong inferences about the functioning of animal minds.


Assuntos
Corvos/fisiologia , Animais , Comportamento de Utilização de Ferramentas/fisiologia
14.
Trials ; 17(1): 524, 2016 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-27788686

RESUMO

BACKGROUND: Study attrition has the potential to compromise a trial's internal and external validity. The aim of the present study was to identify factors associated with participant attrition in a pilot trial of the effectiveness of a novel behavioural support intervention focused on increasing physical activity to reduce smoking, to inform the methods to reduce attrition in a definitive trial. METHODS: Disadvantaged smokers who wanted to reduce but not quit were randomised (N = 99), of whom 61 (62 %) completed follow-up assessments at 16 weeks. Univariable logistic regression was conducted to determine the effects of intervention arm, method of recruitment, and participant characteristics (sociodemographic factors, and lifestyle, behavioural and attitudinal characteristics) on attrition, followed by multivariable logistic regression on those factors found to be related to attrition. RESULTS: Participants with low confidence to quit, and who were undertaking less than 150 mins of moderate and vigorous physical activity per week at baseline were less likely to complete the 16-week follow-up assessment. Exploratory analysis revealed that those who were lost to follow-up early in the trial (i.e., by 4 weeks), compared with those completing the study, were younger, had smoked for fewer years and had lower confidence to quit in the next 6 months. Participants who recorded a higher expired air carbon monoxide reading at baseline were more likely to drop out late in the study, as were those recruited via follow-up telephone calls. Multivariable analyses showed that only completing less than 150 mins of physical activity retained any confidence in predicting attrition in the presence of other variables. CONCLUSIONS: The findings indicate that those who take more effort to be recruited, are younger, are heavier smokers, have less confidence to quit, and are less physically active are more likely to withdraw or be lost to follow-up.


Assuntos
Terapia Comportamental/métodos , Carência Cultural , Terapia por Exercício/métodos , Cooperação do Paciente , Pacientes Desistentes do Tratamento , Pobreza , Fumantes/psicologia , Redução do Consumo de Tabaco/métodos , Fumar/terapia , Adulto , Fatores Etários , Inglaterra , Feminino , Redução do Dano , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Motivação , Análise Multivariada , Razão de Chances , Projetos Piloto , Fatores de Risco , Fumar/psicologia , Fatores de Tempo , Resultado do Tratamento
15.
Psychopharmacology (Berl) ; 233(14): 2765-74, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27256353

RESUMO

RATIONALE: Habitual physical activity (PA) may have an important role in suppressing cigarette cravings. Systematic reviews show a strong acute effect of bouts of PA on reducing cigarette cravings, and it may be that these effects accumulate. OBJECTIVES: The aim was to investigate the relationship between habitual levels of PA and cigarette cravings in disadvantaged smokers not ready to quit by examining baseline cross-sectional data from the Exercise Assisted Reduction then Stop smoking study (EARS). METHODS: A series of linear regression models were applied to investigate the relationship between habitual PA and cigarette cravings and to identify additional predictors of cigarette cravings. The analyses were extended by including interaction terms with PA to identify potential moderators of the relationship between PA and cravings. RESULTS: A higher level of moderate intensity PA was associated with lower cravings (p = 0.033). Additional predictors were the mood and physical symptoms scale (p = 0.007; higher scores were associated with higher cravings) and alcohol consumption (p = 0.002; higher consumption was associated with lower cravings). In addition, a moderation effect of alcohol consumption was found; at higher levels of alcohol consumption, higher PA was significantly associated with higher cravings (p = 0.023). CONCLUSIONS: Overall, participation in regular PA is associated with reduced cigarette cravings; among those with heavy alcohol consumption, this participation is associated with higher cravings. These exploratory analyses suggest that further research into the relationship between PA, alcohol consumption and cigarette cravings is needed.


Assuntos
Fissura/fisiologia , Exercício Físico/psicologia , Fumar/psicologia , Adulto , Consumo de Bebidas Alcoólicas/psicologia , Estudos Transversais , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Fatores Socioeconômicos
16.
Vet J ; 211: 70-4, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27012166

RESUMO

Horses may become hypoxaemic during anaesthesia despite a high inspired oxygen fraction (FiO2). A lower FiO2 is used commonly in human beings to minimise atelectasis and to improve lung function, and previously has been shown to be of potential benefit in horses in experimental conditions. Other studies suggest no benefit to using a FiO2 of 0.5 during clinically relevant conditions; however, low FiO2 (0.65) is commonly used in practice and in a large number of studies. The present study was performed to compare the effect of a commonly used FiO2 of 0.65 versus 0.90 on calculated respiratory indices in anaesthetised mechanically ventilated horses in a clinical setting. Eighteen healthy Thoroughbred horses anaesthetised for experimental laryngeal surgery were recruited into a prospective, non-blinded, randomised clinical study. Before anaesthesia, the horses were randomly allocated into either low (0.65) or high (0.90) FiO2 groups and arterial blood gas (ABG) analysis was performed every 30 min during anaesthesia to allow for statistical analysis of respiratory indices. As expected, PaO2 was significantly lower in horses anaesthetised with a low FiO2, but was sufficient to fully saturate haemoglobin. There were no significant improvements in any of the other respiratory indices. There is no obvious benefit to be gained from the use of a FiO2 of 0.65 compared to 0.90 for mechanically ventilated Thoroughbred horses anaesthetised in lateral recumbency with isoflurane and a medetomidine constant rate infusion.


Assuntos
Anestésicos Inalatórios/administração & dosagem , Gasometria/veterinária , Cavalos/fisiologia , Hipnóticos e Sedativos/administração & dosagem , Isoflurano/administração & dosagem , Medetomidina/administração & dosagem , Oxigênio/sangue , Animais , Feminino , Masculino , Respiração Artificial/veterinária
17.
Br Poult Sci ; 57(3): 295-305, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27023411

RESUMO

The study assesses the effectiveness of reversible head-only and back-of-the-head electrical stunning of chickens using 130-950 mA per bird at 50 Hz AC. Three trials were conducted to compare both stunning systems: (a) behavioural assessment of return of consciousness, (b) insensibility to thermal pain, and (c) assessment of return of brain activity with visually evoked potentials (VEPs). Assessment of behaviour suggested that the period of unconsciousness following head-only electrical stunning was shorter in hens compared to broilers. Stunning across the back-of-the-head delayed the time to return of brainstem function compared to stunning with standard head-only electrodes. Additionally, back-of-the-head stunning produced a more prolonged period of electroanalgesia compared to head-only. Based on examination of return of brain function with VEPs in hens, back-of-the-head stunning produced a shorter-lasting stun than standard head-only. However, even for standard head-only, the stun was notably shorter than previously reported. In some birds, brain function had returned within 9 s after the end of stunning. The results suggest that some birds may recover consciousness prior to or during the neck cut. Based on these findings, back-of-the-head stunning and standard head-only stunning of hens should not be recommended without further development.


Assuntos
Criação de Animais Domésticos/métodos , Galinhas/fisiologia , Eletrochoque/veterinária , Matadouros , Animais , Eletroencefalografia/veterinária , Feminino , Cabeça/fisiologia , Atividade Motora , Distribuição Aleatória , Restrição Física/veterinária , Inconsciência/veterinária
18.
Biol Lett ; 12(2): 20150871, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26843555

RESUMO

Large-scale, comparative cognition studies are set to revolutionize the way we investigate and understand the evolution of intelligence. However, the conclusions reached by such work have a key limitation: the cognitive tests themselves. If factors other than cognition can systematically affect the performance of a subset of animals on these tests, we risk drawing the wrong conclusions about how intelligence evolves. Here, we examined whether this is the case for the A-not-B task, recently used by MacLean and co-workers to study self-control among 36 different species. Non-primates performed poorly on this task; possibly because they have difficulty tracking the movements of a human demonstrator, and not because they lack self-control. To test this, we assessed the performance of New Caledonian crows on the A-not-B task before and after two types of training. New Caledonian crows trained to track rewards moved by a human demonstrator were more likely to pass the A-not-B test than birds trained on an unrelated choice task involving inhibitory control. Our findings demonstrate that overlooked task demands can affect performance on a cognitive task, and so bring into question MacLean's conclusion that absolute brain size best predicts self-control.


Assuntos
Encéfalo/anatomia & histologia , Corvos/fisiologia , Comportamento Exploratório , Autocontrole , Animais , Comportamento de Escolha , Feminino , Masculino , Recompensa
19.
Psychopharmacology (Berl) ; 231(7): 1267-75, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24522330

RESUMO

RATIONALE: The effects of acute bouts of physical activity (PA) on Strength of Desire (SoD) and Desire to Smoke (DtS) using individual participant data (IPD) from 19 acute randomised controlled studies were quantified. However, there is a need to identify factors influencing this relationship. OBJECTIVES: To understand who most benefits from PA, whether changes in affect mediate these effects and whether any specific attributes of PA are associated with cigarette cravings. METHODS: IPD (n = 930) contributed to one-stage IPD meta-analyses. Participants engaging in PA were compared against controls, using post-intervention DtS and SoD (when DtS is not available) with baseline adjustments. The craving scales were linearly rescaled to 0-100 % (a mean difference between groups of -10 would indicate that post-intervention cravings were 10 % lower in the PA compared with the control group). Demographic, smoking and other characteristics were examined as predictors and potential moderators, whereas change in affect was considered as a mediator. PA was categorised according to type, duration and intensity, to determine PA attributes associated with cravings reduction. RESULTS: None of the included covariates were shown to moderate or mediate the effects of PA. Intensity of PA was significantly associated with a reduction in cravings; moderate and vigorous intensity PA offered the most benefits. A one-stage IPD meta-analysis yielded effect sizes of -9.22 (-15.24; -3.20) for light, -34.57 (-42.64; -26.50) for moderate and -31.29 (-38.00; -24.57) for vigorous intensity in comparison with controls. CONCLUSIONS: Moderate intensity PA could be recommended to all smokers regardless of demographic, smoking and other characteristics.


Assuntos
Comportamento Aditivo/psicologia , Atividade Motora/fisiologia , Fumar/psicologia , Afeto , Humanos
20.
Equine Vet J ; 46(4): 427-34, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24372991

RESUMO

REASONS FOR PERFORMING STUDY: Ex vivo evidence suggests that cyclo-oxygenase (COX) 2-preferential inhibitor nonsteroidal anti-inflammatory drugs (NSAIDs), such as meloxicam, have a less detrimental effect on intestinal healing than flunixin meglumine (FM). Whether this translates to a beneficial effect in horses with naturally occurring strangulating small intestinal (SSI) lesions is unknown. OBJECTIVES: To compare the clinical outcome of horses with naturally occurring SSI lesions treated with meloxicam or FM. STUDY DESIGN: Randomised prospective study. METHODS: Cases presenting to the Royal Veterinary College Equine Referral Hospital and Bell Equine Veterinary Clinic during 2010 and 2011 in which an SSI lesion was identified at exploratory laparotomy were eligible for inclusion. Horses received either 1.1 mg/kg bwt FM or 0.6 mg/kg bwt meloxicam i.v. q. 12 h. Clinical outcomes and clinical and laboratory parameters associated with endotoxaemia were compared between groups. RESULTS: Sixty cases were enrolled, 32 horses received FM and 28 received meloxicam. There was no difference in signalment, physical examination or surgical factors between groups. The overall survival to discharge was 81%; there was no difference in survival (P = 0.14) or incidence of post operative ileus (P = 0.25) between groups. There was no significant difference between the plasma lipopolysaccharide (LPS) concentrations at 0 h (P = 0.18) or 48 h (P = 0.60); however, there was a significant difference between neutrophil count at 48 h (P<0.05) and at 96 h (P<0.01) with significantly greater cell numbers in horses receiving meloxicam compared with FM. Blinded pain score evaluation showed that more horses receiving meloxicam showed gross signs of pain than those treated with FM (P = 0.04). CONCLUSIONS: Nonsteroidal anti-inflammatory drug choice did not affect major clinical outcomes in horses with SSI lesions but had some effects on signs of pain. This study provides no evidence to recommend one NSAID treatment above another based on survival or the incidence of ileus; however, evaluation of a larger number of cases is required.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Clonixina/análogos & derivados , Doenças dos Cavalos/tratamento farmacológico , Inflamação/veterinária , Complicações Pós-Operatórias/veterinária , Tiazinas/uso terapêutico , Tiazóis/uso terapêutico , Animais , Clonixina/uso terapêutico , Endotoxinas/sangue , Feminino , Doenças dos Cavalos/etiologia , Cavalos , Obstrução Intestinal/cirurgia , Obstrução Intestinal/veterinária , Intestino Delgado/patologia , Intestino Delgado/cirurgia , Masculino , Meloxicam , Complicações Pós-Operatórias/tratamento farmacológico
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