Plasma deposited diamond-like carbon films for large neural arrays

To understand how large systems of neurons communicate, we need to develop methods for growing patterned networks of large numbers of neurons. We have found that diamond-like carbon thin films formed by energetic deposition from a filtered vacuum arc carbon plasma can serve as "neuron friendly" substrates for the growth of large neural arrays. Lithographic masks can be used to form patterns of diamond-like carbon, and regions of selective neuronal attachment can form patterned neural arrays. In the work described here, we used glass microscope slides as substrates on which diamond-like carbon was deposited. PC-12 rat neurons were then cultured on the treated substrates and cell growth monitored. Neuron growth showed excellent contrast, with prolific growth on the treated surfaces and very low growth on the untreated surfaces. Here we describe the vacuum arc plasma deposition technique employed, and summarize results demonstrating that the approach can be used to form large patterns of neurons.Щоб зрозуміти, як взаємодіють між собою великі системи нейронів, ми повинні розвивати методи вирощування рельєфних структур великого числа нейронів. Ми установили, що алмазоподібні вуглецеві тонкі плівки, що утворюються в результаті могутнього опромінення фільтрованою вуглецевою плазмою вакуумної дуги, можуть бути використані в ролі «нейроно-дружелюбніх» субстанцій для вирощування великих нейронних структур. Літографічні маски можуть бути використані для вормування алмазоподібної вуглецевої структури , а області селективного нейронного приєднання можуть утворювати систематичні нейронні структури. В експериментах, описаних нижче, як підкладку ми використовували предметні стекла мікроскопа, на які наносилися алмазоподібні вуглецеві покриття. Потім на опромінених підкладках були вирощені щурячі нейрони PC-12 і спостерігався ріст кліток. Спостерігався величезний контраст у рості нейронів, від багатого росту на опромінених поверхнях до слабкого на неопромінених. У даній роботі описана використовувана для опромінення вакуумно-дугова установка й узагальнені результати, що показують, що даний метод може бути використаний для формування великих структур нейронів.Чтобы понять, как взаимодействуют между собой большие системы нейронов, мы должны развивать методы выращивания рельефных структур большого числа нейронов. Мы установили, что алмазоподобные углеродные тонкие пленки, образующиеся в результате мощного облучения фильтрованной углеродной плазмой вакуумной дуги, могут быть использованы в качестве «нейроно-дружелюбных» субстанций для выращивания больших нейронных структур. Литографические маски могут применяться для формирования алмазоподобной углеродной структуры, а области селективного нейронного присоединения могут образовывать систематические нейронные структуры. В экспериментах, описываемых ниже, в качестве подложки мы использовали предметные стекла микроскопа, на которые наносились алмазоподобные углеродные покрытия. Затем на облученных подложках были выращены крысиные нейроны PC-12 и наблюдался рост клеток. Отслежен огромный контраст в росте нейронов, от обильного роста на облученных поверхностях до слабого на необлученных. В данной работе описана используемая для облучения вакуумно- дуговая установка и обобщены результаты, показывающие, что данный метод может быть использован для формирования больших структур нейронов

Evolution of Models to Support Community and Policy Action with Science: Balancing Pastoral Livelihoods and Wildlife Conservation in Savannas of East Africa

We developed a “continual engagement” model to better integrate knowledge from policy makers, communities, and researchers with the goal of promoting more effective action to balance poverty alleviation and wildlife conservation in 4 pastoral ecosystems of East Africa. The model involved the creation of a core boundary-spanning team, including community facilitators, a policy facilitator, and transdisciplinary researchers, responsible for linking with a wide range of actors from local to global scales. Collaborative researcher–facilitator community teams integrated local and scientific knowledge to help communities and policy makers improve herd quality and health, expand biodiversity payment schemes, develop land-use plans, and fully engage together in pastoral and wildlife policy development. This model focused on the creation of hybrid scientific–local knowledge highly relevant to community and policy maker needs. The facilitation team learned to be more effective by focusing on noncontroversial livelihood issues before addressing more difficult wildlife issues, using strategic and periodic engagement with most partners instead of continual engagement, and reducing costs by providing new scientific information only when deemed essential. We conclude by examining the role of facilitation in redressing asymmetries in power in researcher–community–policy maker teams, the role of individual values and character in establishing trust, and how to sustain knowledge-action links when project funding ends

Comprehensive analysis of epigenetic clocks reveals associations between disproportionate biological ageing and hippocampal volume

The concept of age acceleration, the difference between biological age and chronological age, is of growing interest, particularly with respect to age-related disorders, such as Alzheimer’s Disease (AD). Whilst studies have reported associations with AD risk and related phenotypes, there remains a lack of consensus on these associations. Here we aimed to comprehensively investigate the relationship between five recognised measures of age acceleration, based on DNA methylation patterns (DNAm age), and cross-sectional and longitudinal cognition and AD-related neuroimaging phenotypes (volumetric MRI and Amyloid-β PET) in the Australian Imaging, Biomarkers and Lifestyle (AIBL) and the Alzheimer’s Disease Neuroimaging Initiative (ADNI). Significant associations were observed between age acceleration using the Hannum epigenetic clock and cross-sectional hippocampal volume in AIBL and replicated in ADNI. In AIBL, several other findings were observed cross-sectionally, including a significant association between hippocampal volume and the Hannum and Phenoage epigenetic clocks. Further, significant associations were also observed between hippocampal volume and the Zhang and Phenoage epigenetic clocks within Amyloid-β positive individuals. However, these were not validated within the ADNI cohort. No associations between age acceleration and other Alzheimer’s disease-related phenotypes, including measures of cognition or brain Amyloid-β burden, were observed, and there was no association with longitudinal change in any phenotype. This study presents a link between age acceleration, as determined using DNA methylation, and hippocampal volume that was statistically significant across two highly characterised cohorts. The results presented in this study contribute to a growing literature that supports the role of epigenetic modifications in ageing and AD-related phenotypes

Uncovering the heterogeneity and temporal complexity of neurodegenerative diseases with Subtype and Stage Inference

The heterogeneity of neurodegenerative diseases is a key confound to disease understanding and treatment development, as study cohorts typically include multiple phenotypes on distinct disease trajectories. Here we introduce a machine-learning technique\u2014Subtype and Stage Inference (SuStaIn)\u2014able to uncover data-driven disease phenotypes with distinct temporal progression patterns, from widely available cross-sectional patient studies. Results from imaging studies in two neurodegenerative diseases reveal subgroups and their distinct trajectories of regional neurodegeneration. In genetic frontotemporal dementia, SuStaIn identifies genotypes from imaging alone, validating its ability to identify subtypes; further the technique reveals within-genotype heterogeneity. In Alzheimer\u2019s disease, SuStaIn uncovers three subtypes, uniquely characterising their temporal complexity. SuStaIn provides fine-grained patient stratification, which substantially enhances the ability to predict conversion between diagnostic categories over standard models that ignore subtype (p = 7.18 7 10 124 ) or temporal stage (p = 3.96 7 10 125 ). SuStaIn offers new promise for enabling disease subtype discovery and precision medicine

Global significance of extensive grazing lands and pastoral societies: An introduction

More of the land surface of the earth is used for grazing than for any other purpose (FAO 1999, WRI 2000, Asner et al. 2004, Ojima and Chuluun, Chapter 8). Although livestock and wildlife graze in forests and woodlands, we focus here on the lands where most herding peoples and their livestock graze: in ‘open’ grazing lands, which include savannas, grasslands, prairies, steppe, and shrublands (Asner et al. 2004). These grazing lands cover 61.2 million km2 or 45% of the earth’s surface (excluding Antarctica), 1.5 times more of the globe than forest, 2.8 times more than cropland and 17 times more than urban settlements (see Figure 1-1)2. These lands range from extremely dry (hyper-arid) to very wet (humid) and represent 78% of the land area grazed by livestock (Asner et al. 2004)

Seasonal patterns of energy allocation to basal metabolism, activity and production for livestock in a nomadic pastoral ecosystem

Presents energy budgets and estimates of forage intake requirements developed for adult camels, cattle, sheep and goats managed by nomads of the arid Turkana district of north - western Kenya. Includes data on livestock activity patterns, diet quality, weight changes and milk yields with literature based estimates of the associated costs and efficiencie

An agro-pastoral household model for the rangelands of East Africa

East Africa contains areas with some of the greatest large mammal biodiversity on the planet. These areas are key natural resources for the economic development of the region. They are also key areas for pastoralists who have co-existed with wildlife for millennia. Increasing populations, conflicts between wildlife and cattle, and the growth of agriculture, are all placing great pressure on these lands This paper describes the development of a pastoralist socio-economic model that is linked to the Savanna ecosystem model. In this way, options and scenarios could be investigated for their impacts not only on the ecosystem but also on pastoralist households and their welfare. The model, named PHEWS (Pastoral Household and Economic Welfare Simulator), tracks the flow of cash and dietary energy in pastoralist households using a simple set of rules. The model was calibrated for the Ngorongoro Conservation Area (NCA), northern Tanzania. The results of two population increase scenarios are presented. Model results indicate that all households in NCA depend to some degree on outside sources of calories, and that pastoralist welfare in NCA, even with small amounts of agriculture allowed, is under severe pressure at current human population levels. Strengths and weakness of the model are discussed, and next steps in its application identified

Fragmentation in semi-arid and arid landscapes: consequences for human and natural systems

Exploring the concept of fragmentation, the ecological processes interrupted by fragmentation, and the social consequences of fragmented landscapes, this book presents a timely synthesis on the effects of fragmentation on arid and semi-arid pastoral systems throughout the world. The global significance of the world’s rangelands is large, with these arid and semi-arid systems making up almost 25% of the earth’s landscapes – and supporting the livelihoods of more than 20 million people. These ecosystems are also home to several of the planet’s remaining megafauna, as well as other important species. Yet fragmentation across these rangelands has significantly impaired the ability of both people and animals to compensate for temporal heterogeneity in vegetation and water by exploiting its spatial heterogeneity, resulting in limited resource availability. The case is developed that while fragmentation arises from different natural, social and economic conditions worldwide it creates similar outcomes for human and natural systems. With information from nine sites around the world the authors examine how fragmentation occurs, the patterns that result, and the consequences of fragmentation for ecosystems and the people who depend on them. The book will provide a valuable reference for students and researchers in rangeland ecology, park and natural resource management, environmental and ecological anthropology, economics and agriculture

Fragmentation of arid and semi-Arid ecosystems: Implications for people and animals

Human action has modified the earth in many ways, but one of the most pervasive effects of humans on the environment is dissection of natural systems into spatially isolated parts, a process generally known as fragmentation. Fragmentation of environments is not only caused by humans; dynamic natural processes like landslides, fires, and floods can create barriers that dissect natural systems. Understanding the consequences of humancaused and natural sources of fragmentation has been a fundamental challenge in ecology, a problem occupying theoretical and empirical workers for decades (see reviews of Usher 1987, Andren 1994, Collinge 1996, Turner 1996, Young et al. 1996, Harrison and Bruna 1999, Debinski and Holt 2000, Niemela 2001, Chalfoun et al. 2002, de Blois et al. 2002, Schmiegelow and Monkkonen 2002). Moreover, anthropologists and other social scientists have worked to understand the human forces that drive fragmentation of landscapes (Khazanov 1984, Little and Leslie 1999, Kerven 2003). Despite these efforts, understanding of the consequences of landscape fragmentation for human economies and social systems remains rudimentary