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1.
J Chem Inf Model ; 63(18): 5784-5793, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37665618

RESUMO

The basin-hopping algorithm (BHA) allows for the efficient exploration of atomic cluster potential energy surfaces by random perturbations in configuration space, followed by energy minimizations. Here, the taboo search method is incorporated to prevent the search from revisiting recently visited regions of the search space. Two taboo search modes are implemented, one mode resets the search to random coordinates upon encountering the taboo region, while the other simply rejects any proposed move into the taboo region. These two modes are tested and compared on a variety of potential energy surfaces─several clusters where atomic interactions are described by the Lennard-Jones potential, and Au55 where a semi-empirical tight binding potential is used to describe atomic interactions. Some differences in performance between the two taboo search modes were noted for LJ38 and Au55, with the mode that rejects all hops into the taboo region performing better, offering a means to improve the efficiency of the BHA for multifunnel systems. However, both taboo search modes failed to significantly improve performance on multifunnel systems where more than two funnels were present in the system.

2.
J Anim Ecol ; 92(2): 273-284, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35569094

RESUMO

When ecosystems are under severe pressure or environments change, trophic position and intraspecific niche width may decrease or narrow, signalling that conservation action is required. In New Zealand, alpine and subalpine ecosystems have been extensively modified through farming since 19th-century European settlement, with consequences for indigenous species such as the kea Nestor notabilis. We investigated feather stable isotope values in the kea and predicted a lower trophic position in modern kea populations, to reflect reduced lowland habitat and a mixed diet with more plant material. We predicted that size and sex would influence trophic values in this sexually dimorphic species, with larger birds more likely to have a high protein diet. We examined potential dietary changes in 68 museum collected kea from 1880s to 2000s, first recording accession details including provenance and sex and measuring culmen length. We used bulk carbon and nitrogen stable isotope analyses (BSIAs) of feathers and a further feather subset using compound-specific stable isotope analyses of amino acids (CSIA-AA) to obtain isotopic values and estimate trophic position. BSIA showed δ15 N values in kea feathers declined through time and could indicate that early century kea were highly omnivorous, with δ15 N values on average higher than in modern kea. Variance in δ15 N values was greater after 1950, driven by a few individuals. Few differences between males and females were evident, although females in the south region had lower δ15 N values. There was a tendency for large male birds to have higher trophic values, perhaps reflecting dominant male bird behaviour noted in historical records. Nonetheless, CSIA-AA performed on a subset of the data suggested that variation in BSIA is likely due to baseline changes rather than relative trophic position which may be more homogenous than these data indicate. Although there was more variability in modern kea, we suggest caution in interpretation. Stable isotope data, particularly CSIA-AA, from museum specimens can reveal potential change in ecological networks as well as sexually dimorphic feeding patterns within species. The data can reveal temporal and regional variation in species trophic position and changes in ecosystem integrity to inform conservation decision-making.


Assuntos
Ecossistema , Papagaios , Masculino , Feminino , Animais , Museus , Isótopos de Nitrogênio/análise , Dieta , Isótopos de Carbono/análise
3.
Eur J Ageing ; 19(3): 369-379, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36052179

RESUMO

Although a number of empirical studies have found support for distinct emotional information processing biases in young versus older adults, it remains unclear whether these biases are driven by differential processing of positive or negative emotional information (or both) and whether they are moderated by stimulus type, in particular face versus non-face, the former of which is known to be subject to distinct processing. To address these gaps in the literature, our analyses included 2237 younger (mean age = 21.61 years) and 2136 older (mean age = 70.58 years) adults from 73 data sets, 19 involving face stimuli and 54 involving non-face stimuli (objects or scenes). Our findings indicated a significant overall age-related positivity effect (Hedge's g = 0.35) when comparing positive and negative stimuli, but consideration of emotionally neutral stimuli revealed significant age differences in emotional processing for negative stimuli only, with younger adults showing a stronger negativity bias. Furthermore, compared to emotionally neutral stimuli, both younger and older adults showed evidence of biases toward non-face positive and negative stimuli and toward positive but not negative face stimuli. Thus, although the present meta-analysis found evidence of an overall age-related positivity effect consistent with a shift toward positivity with aging, a different picture emerged when comparing emotional against neutral stimuli, and consideration of stimulus type revealed a distinct pattern for face stimuli, which may reflect the biological and social significance of facial expressions. Supplementary Information: The online version contains supplementary material available at 10.1007/s10433-021-00676-w.

4.
Zoo Biol ; 41(3): 226-233, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34951730

RESUMO

The global reach of zoos has enormous potential to raise awareness of conservation issues such as the amphibian extinction crisis. One mechanism of achieving this is through targeted, time-limited campaigns. However, the longer-term impact of such campaigns on conservation outcomes is rarely evaluated. The goal of this study is to evaluate how zoos view "The Year of The Frog," a campaign launched by zoos in 2008, with the aim of raising awareness of the global amphibian crisis and generating funds to support amphibian conservation initiatives. A questionnaire-based survey of 43 zoos from fourteen countries was used to evaluate how zoo practitioners believed the campaign influenced amphibian conservation some 10 years after its launch. Survey results showed that the campaign not only contributed to the improvement of research into amphibian husbandry in zoos but also increased support of in situ conservation of amphibians. Zoos focused on exotic species, but developed countries led most of the actions of the campaign. The campaign has inspired and encouraged some zoos and other ex situ conservation organizations to embrace amphibian conservation. The next step is to increase collaboration with more organizations through, for example, AArk and IUCN SSC/ASG, particularly in countries that have high amphibian biodiversity.


Assuntos
Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Animais , Animais de Zoológico , Anuros , Biodiversidade , Conservação dos Recursos Naturais/métodos
5.
Cancers (Basel) ; 15(1)2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36612143

RESUMO

Current prognostic and diagnostic tests for prostate cancer are not able to accurately distinguish between aggressive and latent cancer. Members of the transforming growth factor-ß (TGFB) family are known to be important in regulating prostate cell growth and some have been shown to be dysregulated in prostate cancer. Therefore, the aims of this study were to examine expression of TGFB family members in primary prostate tumour tissue and the phenotypic effect of activins on prostate cell growth. Tissue cores of prostate adenocarcinoma and normal prostate were immuno-stained and protein expression was compared between samples with different Gleason grades. The effect of exogenous treatment with, or overexpression of, activins on prostate cell line growth and migration was examined. Activin B expression was increased in cores containing higher Gleason patterns and overexpression of activin B inhibited growth of PNT1A cells but increased growth and migration of the metastatic PC3 cells compared to empty vector controls. In contrast, activin C expression decreased in higher Gleason grades and overexpression increased growth of PNT1A cells and decreased growth of PC3 cells. In conclusion, increased activin B and decreased activin C expression is associated with increasing prostate tumor grade and therefore have potential as prognostic markers of aggressive prostate cancer.

6.
Hum Mov Sci ; 69: 102529, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31726292

RESUMO

PURPOSE: The aim of this study was to examine the effect of vision on anticipatory postural control (APA) responses in two groups of clinically diagnosed chronic low back pain patients, those with Posterior Pelvic Girdle pain and those with Non-Specific Low Back Pain compared to a matched group of healthy controls during the modified Trendelenburg task. METHODS: Seventy-eight volunteer participants (60 females and 18 males) gave informed consent to take part in this study. 39 with confirmed LBP or PGP lasting longer than 12 weeks and 39 healthy matched controls performed 40 single leg lift tasks (hip flexion to 90° as quickly as possible) with their non-dominant lower limb. A force plate was used to determine the medial-lateral displacement of the center of pressure, and the initiation of weight shift; kinematics was used to determine initiation of leg lift; and electromyography was used to determine onset times from the external oblique (EO), internal oblique (IO) and lumbar multifidus (MF), gluteus maximus (GM) and biceps femoris (BF). RESULTS: The PGP group showed significantly longer muscle onset latencies in the BF, EO MF with visual occlusion (F2,746 = 4.51, p < .0001). CONCLUSION: The muscle onset delays identified between the two LBP sub-groups suggests that pain may not be the primary factor in alteration of APA response. The PGP group show a greater reliance on vision which may signal impairment in multiple feedback channels.


Assuntos
Dor Crônica/fisiopatologia , Retroalimentação Sensorial , Dor Lombar/fisiopatologia , Dor da Cintura Pélvica/fisiopatologia , Equilíbrio Postural , Adulto , Fenômenos Biomecânicos , Eletromiografia , Feminino , Músculos Isquiossurais/fisiopatologia , Humanos , Extremidade Inferior , Região Lombossacral , Masculino , Adulto Jovem
7.
Zoo Biol ; 38(6): 471-480, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31602677

RESUMO

Despite the global declines in the rate of amphibians, evaluation of public understanding of the crisis has not yet been carried out. We surveyed visitors (n = 1,293) at 15 zoos in Brazil, New Zealand, and the United Kingdom, using a certainty-based assessment method to compare visitor knowledge of the global amphibian crisis. We further analyzed zoo educational material about amphibians to explore its potential to raise awareness through amphibian-focused environmental education. Visitors in the three countries had relatively little understanding of amphibians and the global amphibian crisis. When the degree of confidence in answering the questions (high, medium, and low) is accounted for, correct answers varied between 28% and 39%. This compared to scores of between 58% and 73% when the degree of confidence in responding was not accounted for. However, specific areas of knowledge (e.g., biology, conservation, biogeography, and conceptual ideas) varied significantly across the countries. Visitors had a weaker grasp of biogeographical and conservation issues than general amphibian biology. Zoo visitors in Brazil knew less about amphibian conservation than those in New Zealand or the United Kingdom. There was less amphibian-focused content in educational materials in zoos in Brazil than there was in the United Kingdom. Improving information about the global amphibian crisis may increase support for future conservation actions. Outreach education is one of the most important approaches in any strategic planning for conservation of species. Amphibian-focused environmental education at institutions such as zoos and aquaria can be a crucial intervention to support amphibian conservation worldwide.


Assuntos
Anfíbios , Conservação dos Recursos Naturais , Adolescente , Adulto , Animais , Brasil , Coleta de Dados , Humanos , Nova Zelândia , Dinâmica Populacional , Reino Unido , Adulto Jovem
8.
Hum Mov Sci ; 66: 173-185, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31029839

RESUMO

Dynamic situations, such as interactive sports or walking on a busy street, impose high demands on a person's ability to interact with (others in) its environment (i.e., 'interact-ability'). The current study examined how distance regulation, a fundamental component of these interactions, is mediated by different sources of visual information. Participants were presented with a back and forwards moving virtual leader, which they had to follow by walking back and forwards themselves. We presented the leader in several appearances that differed in the presence of segmental (i.e., relative movements of body segments), cadence-related (i.e., sway and bounce), and global (i.e., optical expansion-compression) information. Results indicated that removing segmental motion information from the virtual leader significantly deteriorated both temporal synchronization and spatial accuracy of the follower to the leader, especially when the movement path of the leader was less regular/predictable. However, no difference was found between cadence-related and global motion information appearances. We argue that regulating distance with others effectively requires a versatile attunement to segmental and global motion information depending on the specific task demands. The results further support the notion that detection of especially segmental information allows for more timely 'anticipatory' tuning to another person's locomotor movements and intentions.

9.
J Clin Exp Neuropsychol ; 40(10): 1062-1073, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29978753

RESUMO

OBJECTIVE: This study assessed deficits associated with Parkinson's disease (PD) at two time points separated by 1 year using a computerized neuropsychological battery, and determined interrelationships with conventional clinical measures of cognitive functioning (Montreal Cognitive Assessment; MoCA) and motor impairment (Part III of the Unified PD Rating Scale; UPDRS), as well as other factors known to influence cognitive dysfunction in PD. METHOD: Participants included 37 with PD and 47 controls. Linear mixed-effects models were developed for each computerized task. RESULTS: Results showed that the PD group performed worse than controls on all of the computerized tasks at both time points. In contrast, MoCA scores differed between PD and controls only at follow-up. However, the MoCA detected decline over the year in the PD group, whereas only one of the computerized tasks did. In both groups, higher MoCA scores predicted better performance on some but not all of the computerized tasks. Surprisingly, UPDRS-rated motor impairment did not predict performance on any of the computerized tasks, and aside from older age, which predicted poorer performance on all but one task, the other factors-education, affective and impulsivecompulsive symptoms, sleep quality, dopaminergic medication-generally had no relationship with performance on the computerized tasks. CONCLUSIONS: The presence of performance deficits for all of the computerized tasks in the PD group compared to controls, but not for the MoCA at initial testing, indicates that the computerized battery was better able to detect deficits. However, in contrast to the MoCA, the current results call into question the suitability of the computerized battery as measured here for tracking decline.


Assuntos
Diagnóstico por Computador/métodos , Testes Neuropsicológicos , Doença de Parkinson/complicações , Doença de Parkinson/psicologia , Idoso , Idoso de 80 Anos ou mais , Cognição/fisiologia , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/psicologia , Disfunção Cognitiva/psicologia , Feminino , Humanos , Masculino , Testes de Estado Mental e Demência , Pessoa de Meia-Idade , Movimento , Desempenho Psicomotor
10.
Physiol Biochem Zool ; 91(4): 950-966, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29863954

RESUMO

The thermal sensitivity of physiological rates is a key characteristic of organisms. For tuatara (Sphenodon punctatus), the last surviving member of the reptilian order Rhynchocephalia and an unusually cold-tolerant reptile, we aimed to clarify responses in indices of metabolic rate (oxygen consumption [[Formula: see text]] and carbon dioxide production [[Formula: see text]]) as well as rates of total evaporative water loss (TEWL) to temperatures at the warmer end of the known tolerated range; currently, patterns for metabolic rate are unclear above 25°C, and TEWL has not been measured above 25°C. We first established that metabolic rate was lowest during the photophase and then measured [Formula: see text], [Formula: see text], and TEWL at six temperatures (12°, 20°, 24°, 27°, 29°, and 30°C) during this phase. Consistent with our predictions, we found that mass-adjusted [Formula: see text], [Formula: see text], and TEWL increased at least 3.5-fold between 12° and 30°C (at 30°C, rates were 2.509 mL g-1 h-1, 2.001 mL g-1 h-1, and 1.829 mg-1 g-1 h-1, respectively). Temperature coefficients (Q10 values) for mass-adjusted [Formula: see text] and TEWL showed thermal dependence between 12° and 29°C but with a reduced increase or thermal independence between 29° and 30°C. There was no observed effect of egg incubation temperature (inferred sex) on the subsequent metabolic rates of juveniles. The respiratory exchange ratio implied a switch from carbohydrate metabolism at <22°C to lipid metabolism at >27°C. The rigorous measurement of [Formula: see text] and TEWL provides a basis for future studies to predict the thermal sensitivity of tuatara to human-mediated climate change.


Assuntos
Metabolismo Basal/fisiologia , Clima , Temperatura Alta , Répteis/fisiologia , Perda Insensível de Água/fisiologia , Animais , Ritmo Circadiano , Feminino , Masculino
11.
Appetite ; 127: 230-241, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29751024

RESUMO

The present study focused on adding to the understanding of meat consumption and potential drivers for its reduction in New Zealand. Using the Theory of Planned Behaviour (TPB) and the recently developed Meat-Attachment Questionnaire (MAQ), this study investigated New Zealand consumers' attitudes, motivations and behaviours in regards to meat consumption. Results derive from a questionnaire sent across New Zealand in March 2017, in which 841 responses were obtained from representative consumer panels. Consumer awareness of the severity of meat's environmental impacts was found to be quite low in comparison to other sustainable food behaviours. Motivations for reduction seem to shift across consumer groups, with different considerations rising and falling in importance depending on current meat consumption habits. Among the TPB components, only attitudes were found to accurately and consistently predict willingness and intentions to reduce personal meat intake, while both attitudes and subjective norms predicted agreement with proposed structural measures that would promote meat reduction and/or plant-based food consumption. In addition, the MAQ was found to provide explanatory power above and beyond that of the TPB components alone and this research supports its use as a tool to further understand meat consumption and potential motivations for reduction. The authors believe these results could be useful for governments or organizations wishing to implement meat reduction strategies, as well as providing a stepping stone for further research inquiry into motivations behind meat consumption and its potential reduction.


Assuntos
Preferências Alimentares/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Carne , Adolescente , Adulto , Idoso , Comportamento do Consumidor , Dieta Saudável , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Masculino , Carne/efeitos adversos , Pessoa de Meia-Idade , Motivação , Nova Zelândia , Teoria Psicológica , Inquéritos e Questionários , Desenvolvimento Sustentável , Adulto Jovem
12.
Hum Mov Sci ; 54: 377-387, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28692837

RESUMO

Regulating distance with a moving object or person is a key component of human movement and of skillful interpersonal coordination. The current set of experiments aimed to assess the role of gait mode and body orientation on distance regulation using a cyclical locomotor tracking task in which participants followed a virtual leader. In the first experiment, participants moved in the backward-forward direction while the body orientation of the virtual leader was manipulated (i.e., facing towards, or away from the follower), hence imposing an incongruence in gait mode between leader and follower. Distance regulation was spatially less accurate when followers walked backwards. Additionally, a clear trade-off was found between spatial leader-follower accuracy and temporal synchrony. Any perceptual effects were overshadowed by the effect of one's gait mode. In the second experiment we examined lateral following. The results suggested that lateral following was also constrained strongly by perceptual information presented by the leader. Together, these findings demonstrated how locomotor tracking depends on gait mode, but also on the body orientation of whoever is being followed.


Assuntos
Marcha/fisiologia , Postura/fisiologia , Caminhada/fisiologia , Adulto , Análise de Variância , Humanos , Masculino , Movimento/fisiologia , Orientação/fisiologia , Adulto Jovem
13.
Int J Food Microbiol ; 233: 73-80, 2016 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-27343426

RESUMO

Sub-lethal injury within a microbial population, due to processing treatments or environmental stress, is often assessed as the difference in the number of cells recovered on non-selective media compared to numbers recovered on a "selective media" containing a predetermined maximum non-inhibitory concentration (MNIC) of a selective agent. However, as knowledge of cell metabolic response to injury, population diversity and dynamics increased, the rationale behind the conventional approach of quantifying sub-lethal injury must be scrutinized further. This study reassessed the methodology used to quantify sub-lethal injury for Saccharomyces cerevisiae cells (≈ 4.75 Log CFU/mL) exposed to either a mild thermal (45°C for 0, 10 and 20min) or a mild pulsed electric field treatment (field strengths of 8.0-9.0kV/cm and energy levels of 8, 14 and 21kJ/kg). Treated cells were plated onto either Yeast Malt agar (YM) or YM containing NaCl, as a selective agent at 5-15% in 1% increments. The impact of sub-lethal stress due to initial processing, the stress due to selective agents in the plating media, and the subsequent variation of inhibition following the treatments was assessed based on the CFU count (cell numbers). ANOVA and a generalised least squares model indicated significant effects of media, treatments, and their interaction effects (P<0.05) on cell numbers. It was shown that the concentration of the selective agent used dictated the extent of sub-lethal injury recorded owing to the interaction effects of the selective component (NaCl) in the recovery media. Our findings highlight a potential common misunderstanding on how culture conditions impact on sub-lethal injury. Interestingly for S. cerevisiae cells the number of cells recovered at different NaCl concentrations in the media appears to provide valuable information about the mode of injury, the comparative efficacy of different processing regimes and the inherent degree of resistance within a population. This approach may provide similar information for other micro-organisms.


Assuntos
Saccharomyces cerevisiae/crescimento & desenvolvimento , Contagem de Colônia Microbiana , Eletricidade , Temperatura Alta , Viabilidade Microbiana , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/metabolismo , Cloreto de Sódio/metabolismo
14.
J Ethnopharmacol ; 189: 10-3, 2016 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-27180314

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Root bark from Tabernanthe iboga has been used traditionally in West Africa as a psychoactive substance in religious rituals. In smaller doses it is reported anecdotally to have stimulant properties. AIM OF THE STUDY: To evaluate the influence of a single 20mg ibogaine dose on psychological variables reflecting subjective mood state and a range of cognitive functions. MATERIALS AND METHODS: 21 healthy male volunteers received single 20mg doses of ibogaine after 6 days pretreatment with double-blind paroxetine or placebo. We compared responses to a battery of psychometric tests and subjective mood ratings performed before and 2h after ibogaine dosing, and assessed relationships between changes in test scores and concentrations of active moiety (the sum of molar noribogaine and ibogaine concentrations). Psychological tests were chosen based on responsiveness to opioid and serotonergic ligands. RESULTS: Ibogaine had minimal influence on psychological tests and mood ratings. The ability to selectively ignore distracting spatial information showed some evidence of modulation; however because this effect was limited to the less challenging condition calls into question the reliability of this result. CONCLUSION: We were unable to identify stimulant effects after single 20mg doses of ibogaine. Future research is needed to confirm whether active moiety concentrations impact selective attention abilities while leaving other cognitive functions and mood state unaffected.


Assuntos
Afeto/efeitos dos fármacos , Fármacos do Sistema Nervoso Central/administração & dosagem , Cognição/efeitos dos fármacos , Ibogaína/administração & dosagem , Adulto , Atenção/efeitos dos fármacos , Fármacos do Sistema Nervoso Central/sangue , Fármacos do Sistema Nervoso Central/farmacocinética , Método Duplo-Cego , Esquema de Medicação , Voluntários Saudáveis , Humanos , Ibogaína/análogos & derivados , Ibogaína/sangue , Ibogaína/farmacocinética , Masculino , Testes Neuropsicológicos , Nova Zelândia , Fitoterapia , Plantas Medicinais , Psicometria , Adulto Jovem
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