462 research outputs found
IDENTIFYING APPROPRIATE GERMPLASM FOR PARTICIPATORY BREEDING: AN EXAMPLE FROM THE CENTRAL VALLEYS OF OAXACA, MEXICO
Identifying the appropriate germplasm to be improved is a key component of any participatory breeding effort because of its implications for impacts on social welfare and genetic diversity. This paper describes a method developed to select a subset of 17 populations for a participatory breeding project from a set of 152 maize landraces. The larger set of landraces was collected in order to characterize, for conservation purposes, the maize diversity present in the Central Valleys of Oaxaca, Mexico. The method combines data representing the perspectives of both men and women members of farm households and those of genetic resources specialists, including professional plant breeders, gene bank managers, and social scientists. The different perspectives complement each other. The results show that when the choice of germplasm is based only on the perspective of genetic resources specialists, traits and materials that are important to farm households may be ignored. Such selections may be less valuable to farmers, limiting the impact of the participatory breeding effort on their livelihoods. However, the findings also indicate that relying solely on the perspectives of farm households may lead to lower diversity. Choosing populations based solely on either perspective involves a social cost-either in terms of diversity or in terms of farmer welfare. Although our approach has limitations, many of which are common to participatory research, it represents a systematic method for meeting one of the important challenges of participatory plant breeding.Mexico, Oaxaca, Maize, Zea mays, Land race, Germplasm conservation, Plant breeding, Selecting, Innovation adoption, Social welfare, Welfare economics, On farm research, Participatory research, Farm Management,
Convolutional Networks for Fast, Energy-Efficient Neuromorphic Computing
Deep networks are now able to achieve human-level performance on a broad
spectrum of recognition tasks. Independently, neuromorphic computing has now
demonstrated unprecedented energy-efficiency through a new chip architecture
based on spiking neurons, low precision synapses, and a scalable communication
network. Here, we demonstrate that neuromorphic computing, despite its novel
architectural primitives, can implement deep convolution networks that i)
approach state-of-the-art classification accuracy across 8 standard datasets,
encompassing vision and speech, ii) perform inference while preserving the
hardware's underlying energy-efficiency and high throughput, running on the
aforementioned datasets at between 1200 and 2600 frames per second and using
between 25 and 275 mW (effectively > 6000 frames / sec / W) and iii) can be
specified and trained using backpropagation with the same ease-of-use as
contemporary deep learning. For the first time, the algorithmic power of deep
learning can be merged with the efficiency of neuromorphic processors, bringing
the promise of embedded, intelligent, brain-inspired computing one step closer.Comment: 7 pages, 6 figure
Effect of biofunctionalized implant surface on osseointegration: a histomorphometric study in dogs
Among the different properties that influence bone apposition around implants, the chemical or biochemical composition of implant surface may interfere on its acceptance by the surrounding bone. The aim of this study was to investigate if a biofunctionalization of implant surface influences the bone apposition in a dog model and to compare it with other surfaces, such as a microstructured created by the grit-blasting/acid-etching process. Eight young adult male mongrel dogs had the bilateral mandibular premolars extracted and each one received 6 implants after 12 weeks, totaling 48 implants in the experiment. Four groups of implants were formed with the same microrough topography with or without some kind of biofunctionalization treatment. After histomorphometric analysis, it was observed that the modified microstructured surface with a "low concentration of the bioactive peptide" provided a higher adjacent bone density (54.6%) when compared to the other groups (microstructured + HA coating = 46.0%, microstructured only = 45.3% and microstructured + "high concentration of the bioactive peptide" = 40.7%), but this difference was not statistically significant. In conclusion, biofunctionalization of the implant surface might interfere in the bone apposition around implants, especially in terms of bone density. Different concentrations of bioactive peptide lead to different results.Entre as diferentes propriedades de uma superfície capazes de influenciar a deposição óssea ao redor de implantes, a composição química e bioquímica pode atuar no reconhecimento do tecido ósseo circundante. O presente trabalho investigou a influência da biofuncionalização de superfícies de implante na deposição óssea ao redor dos mesmos em um modelo animal, comparando-as com outras superfícies, como a microtexturizada obtida pelo processo de jateamento e ataque ácido. Metodologicamente, os pré-molares mandibulares bilaterais de 8 cães foram extraídos e após 12 semanas foram instalados 6 implantes em cada cão, constituindo uma amostra de 48 implantes. Dos 4 grupos experimentais de diferentes superfícies, todos continham a mesma microtopografia rugosa, porém possuindo ou não alguma biofuncionalização. A análise histomorfométrica revelou que a superfície microtexturizada modificada pela adição de baixa concentração peptídica obteve uma maior densidade óssea adjacente (54,6%) quando comparada aos outros grupos (microtexturizada + HA = 46%, somente microtexturizada = 45,3% e microtexturizada com adição de alta concentração peptídica = 40,7%), no entanto estas diferenças numéricas não foram estatisticamente significantes. Dentro deste contexto, conclui-se que a biofuncionalização da superfície de implantes pode interferir na aposição óssea, em particular na densidade óssea, e que diferentes concentrações peptídicas podem conduzir a diferentes resultados.FAPES
From working collections to the World Germplasm Project: agricultural modernization and genetic conservation at the Rockefeller Foundation
This paper charts the history of the Rockefeller Foundation’s participation in the collection and long-term preservation of genetic diversity in crop plants from the 1940s through the 1970s. In the decades following the launch of its agricultural program in Mexico in 1943, the Rockefeller Foundation figured prominently in the creation of world collections of key economic crops. Through the efforts of its administrators and staff, the foundation subsequently parlayed this experience into a leadership role in international efforts to conserve so-called plant genetic resources. Previous accounts of the Rockefeller Foundation’s interventions in international agricultural development have focused on the outcomes prioritized by foundation staff and administrators as they launched assistance programs and especially their characterization of the peoples and ‘‘problems’’ they encountered abroad. This paper highlights instead how foundation administrators and staff responded to a newly emergent international agricultural concern—the loss of crop genetic diversity. Charting the foundation’s responses to this concern, which developed only after agricultural modernization had begun and was understood to be produced by the successes of the foundation’s own agricultural assistance programs, allows for greater interrogation of how the foundation understood and projected its central position in international agricultural research activities by the 1970s.Research for this article was supported in part by a grant-in-aid from the Rockefeller Archive Center
Doing politics in the recent Arab uprisings: Towards a political discourse analysis of the Arab Spring slogans
The present paper aims to analyse a number of those slogans collected from the sit-in quarters in Egypt,
Libya and Yemen. Using political discourse analysis, it unravels various typical discourse structures and
strategies that are used in slogans in the construction of a sub-genre of political discourse in the Arab world.
Drawing data from several mediums, including banners, wall graffiti, audio-visual instruments, chanting,
speeches and songs, this paper tries to show the extent to which the slogans serve as a medium by which
political complaints and comments are dispensed and consumed. This paper draws on a rhetorical analysis to
find out their persuasive effect on shaping the Arab intellect and on the change of the political atmosphere
in the region. Lastly, this paper attempts to show to what extent the slogans meet the standards of political
discourse and whether they can be considered as a sub-genre of political discourse or not.IS
Internationalisation and migrant academics: the hidden narratives of mobility
Internationalisation is a dominant policy discourse in higher education today. It is invariably presented as an ideologically neutral, coherent, disembodied, knowledgedriven policy intervention - an unconditional good. Yet it is a complex assemblage of values linked not only to economic growth and prosperity, but also to global citizenship, transnational identity capital, social cohesion, intercultural competencies and soft power (Clifford and Montgomery 2014; De Wit et al. 2015; Kim 2017; Lomer 2016; Stier 2004). Mobility is the sine qua non of the global academy (Sheller 2014). International movements, flows and networks are perceived as valuable transnational and transferable identity capital and as counterpoints to intellectual parochialism. Fluidity metaphors abound as an antidote to stasis e.g. flows, flux and circulations (Urry 2007). For some, internationalisation is conceptually linked to the political economy of neoliberalism and the spatial extension of the market, risking commodification and commercialisation (Matus and Talburt 2009). Others raise questions about what/whose knowledge is circulating and whether internationalisation is a form of re-colonisation and convergence that seeks to homogenise higher education systems (Stromquist 2007). Internationalisation policies and practices, it seems, are complex entanglements of economic, political, social and affective domains. They are mechanisms for driving the global knowledge 2 economy and the fulfilment of personal aspirations (Hoffman 2009). Academic geographical mobility is often conflated with social mobility and career advancement (Leung 2017). However, Robertson (2010: 646) suggested that ‘the romance of movement and mobility ought to be the first clue that this is something we ought to be particularly curious about.
Adapted MMSE and TYM cognitive tests: how much powerful in screening for Alzheimer�s disease in Iranian people
Alzheimer�s disease (AD) is a major global health priority and providing an efficient way for early diagnosis of people developing dementia is important. The Mini-Mental State Examination (MMSE, total score = 30) and Test Your Memory (TYM, total score = 50) are widely used as screening tests for cognitive function. In the present study 174 subjects including healthy people (CON group) and those having Alzheimer�s disease (AD group) were introduced to MMSE and TYM cognitive tests adjusted to Iranian population. Sensitivities and specificities with optimal cut-off scores, area under curve (AUC), positive predictive value (PPV) and negative predictive value (NPV) were measured for both tests. The MMSE scores of the CON and AD groups were 23.77 ± 0.327 and 10.88 ± 0.762, respectively. The TYM scores were 44.32 ± 0.389 and 14.37 ± 1.368 in the CON and AD participants, respectively. Findings in the MMSE test were: AUC = 0.962, optimal cut-off score = 18.5, sensitivity = 0.90 and specificity = 0.96. Values in the TYM test were: AUC = 0.991, optimal cut-off score = 31, sensitivity = 0.90 and specificity = 1. We found no correlation between the cognitive performance and age in the CON group but a positive correlation in the AD patients. On the other hand, t-test analysis indicated that achievement of the test scores are significantly sex dependent, with more scores attained by the females. Taken together, in regard to correct classification rate (CCR); the TYM test seems to be more appropriate for cognitive screening in our study. However, considering an analogous AUC, both tests are comparable and have high sensitivity and specificity for discriminating between people with and without AD. © 2019, © 2019 Informa UK Limited, trading as Taylor & Francis Group
Bibliometric analysis and short survey in CT scan image segmentation: identifying ischemic stroke lesion areas
Ischemic stroke remains one of the leading causes of mortality and long-term disability worldwide. Accurate segmentation of brain lesions plays a crucial role in ensuring reliable diagnosis and effective treatment planning, both of which are essential for improving clinical outcomes. This paper presents a bibliometric analysis and a concise review of medical image segmentation techniques applied to ischemic stroke lesions, with a focus on tomographic imaging data. A total of 2,014 publications from the Scopus database (2013–2023) were analyzed. Sixty key studies were selected for in-depth examination: 59.9% were journal articles, 29.9% were conference proceedings, and 4.7% were conference reviews. The year 2023 marked the highest volume of publications, representing 17% of the total. The most active countries in this area of research are China, the United States, and India. "Image segmentation" emerged as the most frequently used keyword. The top-performing studies predominantly used pre-trained deep learning models such as U-Net, ResNet, and various convolutional neural networks (CNNs), achieving high accuracy. Overall, the findings show that image segmentation has been widely adopted in stroke research for early detection of clinical signs and post-stroke evaluation, delivering promising outcomes. This study provides an up-to-date synthesis of impactful research, highlighting global trends and recent advancements in ischemic stroke medical image segmentation
Hydrothermal Synthesis and Characterization of Sodalite from Feldspar Mesawa Minerals
The mineral feldspar is a potential raw material in zeolite synthesis because of the high content of SiO2 and Al2O3. Characterization of X-ray diffraction (XRD) and X-ray fluorescence (XRF) on Mesawa feldspar minerals showed high crystallinity and aluminosilicate composition. The synthesis process uses the hydrothermal method with various times and concentrations of NaOH. The sample was mixed with NaOH, stirred until homogeneous at 300 rpm for 1 hour, and transferred to an autoclave. The autoclave was tightly closed and heated in an oven at 170 °C for 72 hours. XRD and XRF analysis revealed that the feldspar mineral had changed to sodalite with a purity of 90.89% and 90.06%; with a yield of 80.89% and 87.36%. FTIR characteristics show a specific peak for sodalite at 422-460 cm-1 related to Si-O bond vibrations, and absorption bands at 698 and 719 cm-1 related to Al-OH vibrations. The SEM results confirmed the morphology of the sodalite resembling balls like raspberries". This research proves that the Mesawa feldspar mineral sample contains type 6 secondary building units, the same blocks as zeolite analcime and cancrinite, so it has the potential as an adsorbent for heavy metals and as a catalyst alternativ
Three‐Dimensional Micro‐Computed Tomographic Imaging of Alveolar Bone in Experimental Bone Loss or Repair
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/142030/1/jper0273.pd
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