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1.
Trop Med Int Health ; 29(7): 599-611, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38757387

RESUMO

OBJECTIVES: Although the link between poverty and tuberculosis (TB) is widely recognised, limited studies have investigated the association between neighbourhood factors and TB incidence. Since the factors influencing different episodes of TB might be different, this study focused on the first episode of TB disease (first-episode TB). METHODS: All first episodes in previously linked and geocoded TB notification data from 2007 to 2015 in Cape Town, South Africa, were aggregated at the neighbourhood level and merged with the 2011 census data. We conducted an ecological study to assess the association between neighbourhood incidence of first-episode TB and neighbourhood factors (total TB burden [all episodes] in the previous year, socioeconomic index, mean household size, mean age, and percentage males) using a negative binomial regression. We also examined the presence of hotspots in neighbourhood TB incidence with the Global Moran's I statistic and assessed spatial dependency in the association between neighbourhood factors and TB incidence using a spatial lag model. RESULTS: The study included 684 neighbourhoods with a median first-episode TB incidence rate of 114 (IQR: 0-345) per 100,000 people. We found lower neighbourhood socioeconomic index (SEI), higher neighbourhood total TB burden, lower neighbourhood mean household size, and lower neighbourhood mean age were associated with increased neighbourhood first-episode TB incidence. Our findings revealed a hotspot of first-episode TB incidence in Cape Town and evidence of spatial dependency in the association between neighbourhood factors and TB incidence. CONCLUSION: Neighbourhood TB burden and SEI were associated with first-episode TB incidence, and there was spatial dependency in this association. Our findings can inform targeted interventions to reduce TB in high-risk neighbourhoods, thereby reducing health disparities and promoting health equity.


Assuntos
Características de Residência , Fatores Socioeconômicos , Análise Espacial , Tuberculose , Humanos , África do Sul/epidemiologia , Incidência , Feminino , Masculino , Tuberculose/epidemiologia , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Características da Vizinhança , Adolescente , Fatores de Risco , Criança , Pobreza , Pré-Escolar , Características da Família
2.
J Anat ; 240(2): 279-295, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34519035

RESUMO

Skeletal muscles attach to bone at their origins and insertions, and the interface where tendon meets bone is termed the attachment site or enthesis. Mechanical stresses at the muscle/tendon-bone interface are proportional to the surface area of the bony attachment sites, such that a larger attachment site will distribute loads over a wider area. Muscles that are frequently active and/or are of larger size should cause attachment sites to hypertrophy (training effect); however, experimental studies of animals subjected to exercise have provided mixed results. To enhance our ability to detect training effects (a type of phenotypic plasticity), we studied a mouse model in which 4 replicate lines of High Runner (HR) mice have been selectively bred for 57 generations. Selection is based on the average number of wheel revolutions on days 5 & 6 of a 6-day period of wheel access as young adults (6-8 weeks old). Four additional lines are bred without regard to running and serve as non-selected controls (C). On average, mice from HR lines voluntarily run ~3 times more than C mice on a daily basis. For this study, we housed 50 females (half HR, half C) with wheels (Active group) and 50 (half HR, half C) without wheels (Sedentary group) for 12 weeks starting at weaning (~3 weeks old). We tested for evolved differences in muscle attachment site surface area between HR and C mice, plastic changes resulting from chronic exercise, and their interaction. We used a precise, highly repeatable method for quantifying the three-dimensional (3D) surface area of four muscle attachment sites: the humerus deltoid tuberosity (the insertion point for the spinodeltoideus, superficial pectoralis, and acromiodeltoideus), the femoral third trochanter (the insertion point for the quadratus femoris), the femoral lesser trochanter (the insertion point for the iliacus muscle), and the femoral greater trochanter (insertion point for the middle gluteal muscles). In univariate analyses, with body mass as a covariate, mice in the Active group had significantly larger humerus deltoid tuberosities than Sedentary mice, with no significant difference between HR and C mice and no interaction between exercise treatment and linetype. These differences between Active and Sedentary mice were also apparent in the multivariate analyses. Surface areas of the femoral third trochanter, femoral lesser trochanter, and femoral greater trochanter were unaffected by either chronic wheel access or selective breeding. Our results, which used robust measurement protocols and relatively large sample sizes, demonstrate that muscle attachment site morphology can be (but is not always) affected by chronic exercise experienced during ontogeny. However, contrary to previous results for other aspects of long bone morphology, we did not find evidence for evolutionary coadaptation of muscle attachments with voluntary exercise behavior in the HR mice.


Assuntos
Corrida , Seleção Artificial , Animais , Evolução Biológica , Feminino , Camundongos , Desenvolvimento Muscular , Músculo Esquelético/fisiologia , Corrida/fisiologia
3.
Genet Med ; 23(11): 2087-2095, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34262154

RESUMO

PURPOSE: Ataxia-Telangiectasia Mutated (ATM) has been implicated in the risk of several cancers, but establishing a causal relationship is often challenging. Although ATM single-nucleotide polymorphisms have been linked to melanoma, few functional alleles have been identified. Therefore, ATM impact on melanoma predisposition is unclear. METHODS: From 22 American, Australian, and European sites, we collected 2,104 familial, multiple primary (MPM), and sporadic melanoma cases who underwent ATM genotyping via panel, exome, or genome sequencing, and compared the allele frequency (AF) of selected ATM variants classified as loss-of-function (LOF) and variants of uncertain significance (VUS) between this cohort and the gnomAD non-Finnish European (NFE) data set. RESULTS: LOF variants were more represented in our study cohort than in gnomAD NFE, both in all (AF = 0.005 and 0.002, OR = 2.6, 95% CI = 1.56-4.11, p < 0.01), and familial + MPM cases (AF = 0.0054 and 0.002, OR = 2.97, p < 0.01). Similarly, VUS were enriched in all (AF = 0.046 and 0.033, OR = 1.41, 95% CI = 1.6-5.09, p < 0.01) and familial + MPM cases (AF = 0.053 and 0.033, OR = 1.63, p < 0.01). In a case-control comparison of two centers that provided 1,446 controls, LOF and VUS were enriched in familial + MPM cases (p = 0.027, p = 0.018). CONCLUSION: This study, describing the largest multicenter melanoma cohort investigated for ATM germline variants, supports the role of ATM as a melanoma predisposition gene, with LOF variants suggesting a moderate-risk.


Assuntos
Ataxia Telangiectasia , Melanoma , Proteínas Mutadas de Ataxia Telangiectasia/genética , Austrália , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Humanos , Melanoma/genética
4.
Regul Toxicol Pharmacol ; 120: 104842, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33346014

RESUMO

Non-dioxin like polychlorinated biphenyls (NDL PCB) are recognized neurotoxicants with implications on altered neurodevelopment and neurodegeneration in exposed organisms. NDL PCB neurotoxic relative potency schemes have been developed for a single mechanism, namely activity toward the ryanodine receptor (RyR), or combined mechanisms including, but not limited to, alterations of RyR and dopaminergic pathways. We compared the applicability of the two neurotoxic equivalency (NEQ) schemes and applied each scheme to PCB mixtures found in environmental and human serum samples. A multiple mechanistic NEQ predicts higher neurotoxic exposure concentrations as compared to a scheme based on the RyR alone. Predictions based on PCB ortho categorization, versus homologue categorization, lead to a higher prediction of neurotoxic exposure concentrations, especially for the mMOA. The application of the NEQ schemes to PCB concentration data suggests that PCBs found in fish from US lakes represent a considerable NEQ exposure to fish consuming individuals, that indoor air of schools contained high NEQ concentrations representing an exposure concern when inhaled by children, and that levels already detected in the serum of adults and children may contribute to neurotoxicity. With further validation and in vivo exposure data the NEQ scheme would help provide a more inclusive measure of risk presented by PCB mixtures.


Assuntos
Dioxinas , Monitoramento Ambiental/métodos , Bifenilos Policlorados/toxicidade , United States Environmental Protection Agency , Poluentes Químicos da Água/toxicidade , Animais , Peixes , Humanos , Síndromes Neurotóxicas/diagnóstico , Síndromes Neurotóxicas/epidemiologia , Bifenilos Policlorados/análise , Estados Unidos/epidemiologia , Poluentes Químicos da Água/análise
5.
Int J Obes (Lond) ; 41(8): 1164-1168, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28209971

RESUMO

BACKGROUND: The 'obesity paradox' refers to the fact that obese patients have better outcomes than normal weight patients. This has been observed in multiple cardiovascular conditions, but evidence for obesity paradox in pulmonary hypertension (PH) remains sparse. METHODS: We categorized 267 patients from the National Institute of Health-PH registry into five groups based on body mass index (BMI): underweight, normal weight, overweight, obese and morbidly obese. Mortality was compared in BMI groups using the χ2 statistic. Five-year probability of death using the PH connection (PHC) risk equation was calculated, and the model was compared with BMI groups using Cox proportional hazards regression and Kaplan-Meier (KM) survival curves. RESULTS: Patients had a median age of 39 years (interquartile range 30-50 years), a median BMI of 23.4 kg m-2 (21.0-26.8 kg m-2) and an overall mortality at 5 years of 50.2%. We found a U-shaped relationship between survival and 1-year mortality with the best 1-year survival in overweight patients. KM curves showed the best survival in the overweight, followed by obese and morbidly obese patients, and the worst survival in normal weight and underweight patients (log-rank P=0.0008). In a Cox proportional hazards analysis, increasing BMI was a highly significant predictor of improved survival even after adjustment for the PHC risk equation with a hazard ratio for death of 0.921 per kg m-2 (95% confidence interval: 0.886-0.954) (P<0.0001). CONCLUSION: We observed that the best survival was in the overweight patients, making this more of an 'overweight paradox' than an 'obesity paradox'. This has implications for risk stratification and prognosis in group 1 PH patients.


Assuntos
Hipertensão Pulmonar/complicações , Hipertensão Pulmonar/mortalidade , Peso Corporal Ideal/fisiologia , Sobrepeso/complicações , Sobrepeso/mortalidade , Sistema de Registros , Adulto , Índice de Massa Corporal , Feminino , Humanos , Hipertensão Pulmonar/fisiopatologia , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , National Institutes of Health (U.S.) , Obesidade/classificação , Obesidade/complicações , Obesidade/mortalidade , Obesidade/fisiopatologia , Sobrepeso/classificação , Sobrepeso/fisiopatologia , Prognóstico , Modelos de Riscos Proporcionais , Medição de Risco , Estados Unidos/epidemiologia
6.
Bull Math Biol ; 79(4): 772-787, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28194619

RESUMO

If a browse damage index indicates that a tree has been 50% browsed by herbivores, does this mean half the leaves are entirely eaten or are all the leaves half eaten? Were the affected leaves old or young? Large or small? In sunshine or shade? Understanding what effect browsing will have on the photosynthetic capacity and the plant's survival ability clearly requires a greater understanding of browsing strategy across the canopy than can be given by a single index value. We developed stochastic models of leaf production, growth and consumption using data from kamahi (Weinmannia racemosa) trees in New Zealand which have been browsed by possums (Trichosurus vulpecula), to ascertain which of six feasible browsing strategies possums are most likely to be employing. We compared the area distribution of real fallen leaves to model output in order to select the best model, and used the model to predict the age distribution of leaves on the tree and thus infer its photosynthetic capability. The most likely browsing strategy that possums employ on kamahi trees is a preference for virgin (i.e. previously unbrowsed) leaves, consistent with the idea that browsing increases the production of chemical plant defences. More generally, our results show that herbivore browsing strategy can significantly change the whole-plant photosynthetic capability of any plant and hence its ability to survive, and therefore, herbivore damage indices should be used in conjunction with more detailed information about herbivore browsing strategy.


Assuntos
Herbivoria , Fotossíntese , Plantas , Animais , Folhas de Planta , Processos Estocásticos , Árvores
7.
J Exp Bot ; 67(15): 4523-34, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27312669

RESUMO

Early vigour is an important physiological trait to improve establishment, water-use efficiency, and grain yield for wheat. Phenotyping large numbers of lines is challenging due to the fast growth and development of wheat seedlings. Here we developed a new photo-based workflow to monitor dynamically the growth and development of the wheat canopy of two wheat lines with a contrasting early vigour trait. Multiview images were taken using a 'vegetation stress' camera at 2 d intervals from emergence to the sixth leaf stage. Point clouds were extracted using the Multi-View Stereo and Structure From Motion (MVS-SFM) algorithm, and segmented into individual organs using the Octree method, with leaf midribs fitted using local polynomial function. Finally, phenotypic parameters were calculated from the reconstructed point cloud including: tiller and leaf number, plant height, Haun index, phyllochron, leaf length, angle, and leaf elongation rate. There was good agreement between the observed and estimated leaf length (RMSE=8.6mm, R (2)=0.98, n=322) across both lines. Significant contrasts of phenotyping parameters were observed between the two lines and were consistent with manual observations. The early vigour line had fewer tillers (2.4±0.6) and larger leaves (308.0±38.4mm and 17.1±2.7mm for leaf length and width, respectively). While the phyllochron of both lines was quite similar, the non-vigorous line had a greater Haun index (more leaves on the main stem) on any date, as the vigorous line had slower development of its first two leaves. The workflow presented in this study provides an efficient method to phenotype individual plants using a low-cost camera (an RGB camera is also suitable) and could be applied in phenotyping for applications in both simulation modelling and breeding. The rapidity and accuracy of this novel method can characterize the results of specific selection criteria (e.g. width of leaf three, number of tillers, rate of leaf appearance) that have been or can now be utilized to breed for early leaf growth and tillering in wheat.


Assuntos
Triticum/crescimento & desenvolvimento , Produção Agrícola , Estudos de Associação Genética , Genótipo , Imageamento Tridimensional , Fotografação , Folhas de Planta/anatomia & histologia , Folhas de Planta/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Triticum/anatomia & histologia , Triticum/genética
8.
J Math Biol ; 72(5): 1301-36, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26094055

RESUMO

Glioblastomas are the most aggressive primary brain tumor. Despite treatment with surgery, radiation and chemotherapy, these tumors remain uncurable and few significant increases in survival have been observed over the last half-century. We recently employed a combined theoretical and experimental approach to predict the effectiveness of radiation administration schedules, identifying two schedules that led to superior survival in a mouse model of the disease (Leder et al., Cell 156(3):603-616, 2014). Here we extended this approach to consider fractionated schedules to best minimize toxicity arising in early- and late-responding tissues. To this end, we decomposed the problem into two separate solvable optimization tasks: (i) optimization of the amount of radiation per dose, and (ii) optimization of the amount of time that passes between radiation doses. To ensure clinical applicability, we then considered the impact of clinical operating hours by incorporating time constraints consistent with operational schedules of the radiology clinic. We found that there was no significant loss incurred by restricting dosage to an 8:00 a.m. to 5:00 p.m. window. Our flexible approach is also applicable to other tumor types treated with radiotherapy.


Assuntos
Neoplasias Encefálicas/radioterapia , Fracionamento da Dose de Radiação , Glioblastoma/radioterapia , Animais , Humanos , Modelos Lineares , Conceitos Matemáticos , Camundongos , Modelos Biológicos , Dinâmica não Linear , Planejamento da Radioterapia Assistida por Computador/estatística & dados numéricos , Resultado do Tratamento
9.
Phys Rev Lett ; 115(18): 180501, 2015 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-26565448

RESUMO

Quantum states can be stabilized in the presence of intrinsic and environmental losses by either applying an active feedback condition on an ancillary system or through reservoir engineering. Reservoir engineering maintains a desired quantum state through a combination of drives and designed entropy evacuation. We propose and implement a quantum-reservoir engineering protocol that stabilizes Fock states in a microwave cavity. This protocol is realized with a circuit quantum electrodynamics platform where a Josephson junction provides direct, nonlinear coupling between two superconducting waveguide cavities. The nonlinear coupling results in a single-photon-resolved cross-Kerr effect between the two cavities enabling a photon-number-dependent coupling to a lossy environment. The quantum state of the microwave cavity is discussed in terms of a net polarization and is analyzed by a measurement of its steady state Wigner function.

10.
Ecol Lett ; 16(1): 90-8, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23113938

RESUMO

Mast-seeding plants often produce high seed crops the year after a warm spring or summer, but the warm-temperature model has inconsistent predictive ability. Here, we show for 26 long-term data sets from five plant families that the temperature difference between the two previous summers (ΔT) better predicts seed crops. This discovery explains how masting species tailor their flowering patterns to sites across altitudinal temperature gradients; predicts that masting will be unaffected by increasing mean temperatures under climate change; improves prediction of impacts on seed consumers; demonstrates that strongly masting species are hypersensitive to climate; explains the rarity of consecutive high-seed years without invoking resource constraints; and generates hypotheses about physiological mechanisms in plants and insect seed predators. For plants, ΔT has many attributes of an ideal cue. This temperature-difference model clarifies our understanding of mast seeding under environmental change, and could also be applied to other cues, such as rainfall.


Assuntos
Magnoliopsida/fisiologia , Modelos Biológicos , Sementes/crescimento & desenvolvimento , Temperatura , Árvores/fisiologia , Mudança Climática , Nova Zelândia
11.
Ecology ; 94(12): 2732-43, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24597220

RESUMO

Ecologists are faced with the challenge of how to scale up from the activities of individual plants and animals to the macroscopic dynamics of populations and communities. It is especially difficult to do this in communities of plants where the fate of individuals depends on their immediate neighbors rather than an average over a larger region. This has meant that algorithmic, agent-based models are typically used to understand their dynamics, although certain macroscopic models have been developed for neighbor-dependent, birth death processes. Here we present a macroscopic model that, for the first time, incorporates explicit, gradual, neighbor-dependent plant growth, as a third fundamental process of plant communities. The model is derived from a stochastic, agent-based model, and describes the dynamics of the first and second spatial moments of a multispecies, spatially structured plant community with neighbor-dependent growth, births, and deaths. A simple example shows that strong neighborhood space-filling during tree growth in an even-aged stand of Scots pine is well captured by the spatial-moment model. The space-filling has a spatial signature consistent with that observed in several field studies of forests. Small neighborhoods of interaction, nonuniform spacing of trees, and asymmetric competition all contribute to the buildup of a wide range of tree sizes with some large dominant individuals and many smaller ones.


Assuntos
Ecossistema , Pinus sylvestris/crescimento & desenvolvimento , Pinus sylvestris/fisiologia , Demografia , Modelos Biológicos , Dinâmica Populacional , Processos Estocásticos
12.
Oecologia ; 172(3): 751-66, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23188054

RESUMO

Patterns of herbivore browse at small scales, such as the rate of leaf consumption or plant preferences, drive the impact of herbivores on whole-plant processes, such as growth or survival, and subsequent changes in plant population structure. However, herbivore impacts are often non-linear, highly variable and context-dependent. Understanding the effect of herbivores on plant populations therefore requires a detailed understanding of the relationships that drive small-scale processes, and how these interact to generate dynamics at larger scales. We derive a mathematical model to predict annual rates of browse-induced tree mortality. We model individual plant mortality as a result of rates of foliage production, turnover and herbivore intake, and extend the model to the population scale by allowing for between-tree variation in levels of herbivore browse. The model is configurable for any broadleaved tree species subject to vertebrate or invertebrate browse, and is designed to be parameterized from field data typically collected as part of browse damage assessments. We parameterized and tested the model using data on foliage cover and browse damage recorded on kamahi trees (Weinmannia racemosa) browsed by possums (Trichosurus vulpecula) in New Zealand forests. The model replicated observed patterns of tree mortality at 12 independent validation sites with a wide range of herbivore densities and browse damage. The model reveals two key thresholds; in plant foliar cover, indicating when individual trees may be at high risk from browse-induced mortality, and in herbivore intake, leading to high rates of mortality across the whole population.


Assuntos
Herbivoria , Plantas , Animais , Modelos Teóricos
13.
Nat Genet ; 25(1): 55-7, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10802656

RESUMO

Gliomas are the most common primary malignant brain tumours and are classified into four clinical grades, with the most aggressive tumours being grade 4 astrocytomas (also known as glioblastoma multiforme; GBM). Frequent genetic alterations in GBMs (refs 2-5) result in stimulation of common signal transduction pathways involving Ras, Akt and other proteins. It is not known which of these pathways, if any, are sufficient to induce GBM formation. Here we transfer, in a tissue-specific manner, genes encoding activated forms of Ras and Akt to astrocytes and neural progenitors in mice. We found that although neither activated Ras nor Akt alone is sufficient to induce GBM formation, the combination of activated Ras and Akt induces high-grade gliomas with the histological features of human GBMs. These tumours appear to arise after gene transfer to neural progenitors, but not after transfer to differentiated astrocytes. Increased activity of RAS is found in many human GBMs (ref. 11), and we show here that Akt activity is increased in most of these tumours, implying that combined activation of these two pathways accurately models the biology of this disease.


Assuntos
Neoplasias Encefálicas/genética , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Proteínas ras/genética , Proteínas ras/metabolismo , Animais , Neoplasias Encefálicas/enzimologia , Neoplasias Encefálicas/etiologia , Linhagem Celular Transformada , Ativação Enzimática/genética , Glioblastoma/enzimologia , Glioblastoma/etiologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt
14.
Nat Genet ; 6(1): 47-51, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8136834

RESUMO

The two most common autosomal dominant dystrophies of the corneal stroma are lattice corneal dystrophy type I and granular dystrophy. A third autosomal dominant stromal dystrophy (Avellino) has also been recognized. Chromosome linkage analysis of four families with Avellino dystrophy mapped the disease-causing gene to chromosome 5q. Subsequent linkage analysis of two families with typical lattice dystrophy and two with typical granular dystrophy also revealed significant linkage with the same markers. Thus, each of three clinically and histopathologically distinct phenotypes is independently linked to 5q. The maximum combined lod score using all 114 affected patients was 28.6 with marker D5S393. None of the 14 known human amyloid-associated genes map to chromosome 5.


Assuntos
Cromossomos Humanos Par 5 , Distrofias Hereditárias da Córnea/genética , Alelos , Amiloide/genética , Mapeamento Cromossômico , Distrofias Hereditárias da Córnea/patologia , Feminino , Genes Dominantes , Ligação Genética , Marcadores Genéticos , Humanos , Itália/etnologia , Escore Lod , Masculino , Linhagem , Estados Unidos
15.
R Soc Open Sci ; 10(6): 221362, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37351496

RESUMO

Reproduction in an uncertain world is fraught. The consequences of investing in too many offspring in a resource poor season can be disastrous but so too is missing the opportunity of a resource rich year. We consider a simple population and individual growth model and use Lyapunov exponents to find analytical results for the optimum brood size under stochastic environmental conditions. We show that if the environment shows dramatic changes between breeding seasons choosing a smaller brood size is more likely to be successful but the best strategy is to synchronize your reproduction to the food availability. Finally, we show that if the cost of having offspring is high it can be better to live in a highly varying world with a plastic strategy that synchronizes to the environment than to live in a deterministic world with a constant strategy, a finding with implications for invasive species and climate change.

16.
Psychol Med ; 42(5): 903-20, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21939592

RESUMO

Taxometric research methods were developed by Paul Meehl and colleagues to distinguish between categorical and dimensional models of latent variables. We have conducted a comprehensive review of published taxometric research that included 177 articles, 311 distinct findings and a combined sample of 533 377 participants. Multilevel logistic regression analyses have examined the methodological and substantive variables associated with taxonic (categorical) findings. Although 38.9% of findings were taxonic, these findings were much less frequent in more recent and methodologically stronger studies, and in those reporting comparative fit indices based on simulated comparison data. When these and other possible confounds were statistically controlled, the true prevalence of taxonic findings was estimated at 14%. The domains of normal personality, mood disorders, anxiety disorders, eating disorders, externalizing disorders, and personality disorders (PDs) other than schizotypal yielded little persuasive evidence of taxa. Promising but still not definitive evidence of psychological taxa was confined to the domains of schizotypy, substance use disorders and autism. This review indicates that most latent variables of interest to psychiatrists and personality and clinical psychologists are dimensional, and that many influential taxonic findings of early taxometric research are likely to be spurious.


Assuntos
Transtornos Mentais/classificação , Transtornos Mentais/diagnóstico , Personalidade , Projetos de Pesquisa , Humanos , Determinação da Personalidade , Transtornos da Personalidade/classificação , Transtornos da Personalidade/diagnóstico , Psicopatologia
17.
ACS Appl Mater Interfaces ; 14(30): 35157-35166, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35862906

RESUMO

Understanding the mechanism of antiwear (AW) tribofilm formation and how to tune surface chemistry to control functionality is essential for the development of the next generation of oil lubricants. In particular, understanding and optimizing early AW tribofilm formation can increase the energy efficiency of mechanical systems. However, the mechanism for how these films form is not well understood. The majority of prior work has focused on analyzing only end-of-test surfaces long after the film has formed. In this work, we develop an in situ multimodal chemical imaging methodology to directly visualize the early formation of AW films on steel surfaces. We investigate an oil formulation containing a phosphorus-based additive commonly used to protect surfaces from wear and fatigue processes in machine elements, such as gears, bearings, and sliding contacts. Using nanoscale multimodal chemical imaging on combined platforms of atomic force microscopy (AFM) coupled directly with in situ nano-infrared (nano-IR) spectroscopy, and further combined ex situ with time-of-flight secondary ion mass spectrometry (ToF-SIMS), we demonstrate a direct correlation between changes in friction and local surface chemistry. In these experiments, the AFM probe acts as a single asperity contact to generate the tribofilm as well as a tool to analyze it in situ as it is forming. To verify our in situ measurements, we compare these results to the ex situ ToF-SIMS of macroscale block-on-ring tribometer-formed samples. The understanding gained here on how AW films form and how film properties can be modified by tuning the chemistry of the additives will facilitate developing transmission fluids to meet increasing demands for vehicle performance and efficiency.

18.
Int J Tuberc Lung Dis ; 26(2): 150-157, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35086627

RESUMO

BACKGROUND: Data suggest that treatment with newer TB drugs (linezolid [LZD], bedaquiline [BDQ] and delamanid [DLM]), used in Khayelitsha, South Africa, since 2012, reduces mortality due to rifampicin-resistant TB (RR-TB).METHODS: This was a retrospective cohort study to assess 6-month mortality among RR-TB patients diagnosed between 2008 and 2019.RESULTS: By 6 months, 236/2,008 (12%) patients died; 12% (78/651) among those diagnosed in 2008-2011, and respectively 8% (49/619) and 15% (109/738) with and without LZD/BDQ/DLM in 2012-2019. Multivariable analysis showed a small, non-significant mortality reduction with LZD/BDQ/DLM use compared to the 2008-2011 period (aOR 0.79, 95% CI 0.5-1.2). Inpatient treatment initiation (aOR 3.2, 95% CI 2.4-4.4), fluoroquinolone (FQ) resistance (aOR 2.7, 95% CI 1.8-4.2) and female sex (aOR 1.5, 95% CI 1.1-2.0) were also associated with mortality. When restricted to 2012-2019, use of LZD/BDQ/DLM was associated with lower mortality (aOR 0.58, 95% CI 0.39-0.87).CONCLUSIONS: While LZD/BDQ/DLM reduced 6-month mortality between 2012 and 2019, there was no significant effect overall. These findings may be due to initially restricted LZD/BDQ/DLM use for those with high-level resistance or treatment failure. Additional contributors include increased treatment initiation among individuals who would have otherwise died before treatment due to universal drug susceptibility testing from 2012, an effect that also likely contributed to higher mortality among females (survival through to care-seeking).


Assuntos
Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Diarilquinolinas/uso terapêutico , Feminino , Humanos , Testes de Sensibilidade Microbiana , Estudos Retrospectivos , Rifampina/farmacologia , Rifampina/uso terapêutico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico
19.
Trends Ecol Evol ; 37(7): 573-581, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35504748

RESUMO

Traits are inherent properties of organisms, but how are they defined for organismal networks such as mycorrhizal symbioses? Mycorrhizal symbioses are complex and diverse belowground symbioses between plants and fungi that have proved challenging to fit into a unified and coherent trait framework. We propose an inclusive mycorrhizal trait framework that classifies traits as morphological, physiological, and phenological features that have functional implications for the symbiosis. We further classify mycorrhizal traits by location - plant, fungus, or the symbiosis - which highlights new questions in trait-based mycorrhizal ecology designed to charge and challenge the scientific community. This new framework is an opportunity for researchers to interrogate their data to identify novel insights and gaps in our understanding of mycorrhizal symbioses.


Assuntos
Micorrizas , Ecologia , Micorrizas/fisiologia , Fenótipo , Plantas/microbiologia , Simbiose
20.
Public Health Action ; 12(2): 55-57, 2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35734003

RESUMO

Patients initiated on drug-resistant TB(DR-TB) treatment in 2019 in Khayelitsha, South Africa, with a loss to follow-up outcome were evaluated to better understand reasons for loss to follow-up and to determine if any had returned to care. Of a total of 187 patients, 28 (15%) were lost to follow-up (LTFU), 24 (86%) of whom were traced: 20/24 (83%) were found when they re-presented to facilities and 8/28 (29%) were linked back to DR-TB care. People with DR-TB continue to seek care even after being LTFU; thus better coordination between different components of the healthcare system are required to re-engage with these patients. Interventions to mitigate the socio-economic challenges of people on DR-TB treatment are needed. Many people who were LTFU and symptomatic were willing to re-engage with DR-TB care, which highlights the importance of for compassionate interventions to welcome them back.


Les patients placés sous traitement pour TB pharmacorésistante (DR-TB) en 2019 à Khayelitsha, Afrique du Sud, et ayant été perdus de vue ont été évalués afin de mieux comprendre les raisons de la perte de vue et de déterminer si certains étaient de nouveau suivis. Sur 187 patients, 28 (15%) ont été perdus de vue, dont 24 (86%) ont été retrouvés : 20/24 (83%) ont été retrouvés lorsqu'ils se sont de nouveau présentés en consultation et 8/28 (29%) ont été réinsérés dans le parcours de soins de la DR-TB. Les patients atteints de DR-TB sont toujours en demande de soins, même après avoir été perdus de vue. Ainsi, une meilleure coordination entre les différentes composantes du système de santé est nécessaire afin de rétablir le lien avec ces patients. Des interventions visant à atténuer les problèmes socio-économiques des patients sous traitement pour DR-TB sont nécessaires. De nombreux patients symptomatiques ayant été perdus de vue étaient enclins à reprendre leur traitement de la DR-TB. Il est donc important de mettre en place des programmes compassionnels afin de les réinsérer dans le parcours de soins.

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