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91.
Comparative evaluation of autofocus algorithms for a real-time system for automatic detection of Mycobacterium tuberculosis 总被引:1,自引:0,他引:1
Mateos-Pérez JM Redondo R Nava R Valdiviezo JC Cristóbal G Escalante-Ramírez B Ruiz-Serrano MJ Pascau J Desco M 《Cytometry. Part A》2012,81(3):213-221
Microscopy images must be acquired at the optimal focal plane for the objects of interest in a scene. Although manual focusing is a standard task for a trained observer, automatic systems often fail to properly find the focal plane under different microscope imaging modalities such as bright field microscopy or phase contrast microscopy. This article assesses several autofocus algorithms applied in the study of fluorescence-labeled tuberculosis bacteria. The goal of this work was to find the optimal algorithm in order to build an automatic real-time system for diagnosing sputum smear samples, where both accuracy and computational time are important. We analyzed 13 focusing methods, ranging from well-known algorithms to the most recently proposed functions. We took into consideration criteria that are inherent to the autofocus function, such as accuracy, computational cost, and robustness to noise and to illumination changes. We also analyzed the additional benefit provided by preprocessing techniques based on morphological operators and image projection profiling. 相似文献
92.
Nasoethmoidal meningocele in a child presenting bilateral congenital cystic adenomatoid malformation: Evidence for a new entity or consequence of gestational exposures?
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Ernani B. da Rosa Daniélle B. Silveira Laís G. Tsugami Nathan L. Bellé Izabelle O. Matos Luciano V. Targa Rosilene da S. Betat André C. da Cunha Rolando A.R. Villacis Sílvia R. Rogatto Luiza E. Dorfman Rafael F. M. Rosa Paulo R.G. Zen 《Birth defects research. Part A, Clinical and molecular teratology》2016,106(4):225-231
93.
Wagner A. Chiba de Castro Rafael O. Xavier Federico H. L. Garrido Jair H. C. Romero Cleto K. Peres Ruberval C. da Luz 《Journal of Plant Ecology》2019,12(4):713
Aims
Invasive plants modify the structure and functioning of natural environments and threat native plant communities. Invasive species are often favored by human interference such as the creation of artificial forest edges. Field removal experiments may clarify if invasive plants are detrimental to native plant regeneration and how this is related to other local factors. We assessed the joint effect of environment and competition with the invasiveTradescantia zebrinaon tree species recruitment in an Atlantic Forest fragment. 相似文献
94.
Filipe Manuel Clemente Rodrigo Ramirez-Campillo Daniel Castillo Javier Raya-Gonzlez Markel Rico-Gonzlez Rafael Oliveira Thomas Rosemann Beat Knechtle 《Biology of sport / Institute of Sport》2022,39(3):765
Plyometric jump training (PJT) can be used for improving balance through bilateral and unilateral jump-landing drills. Since the increased number of articles testing the effects of PJT on dynamic and static balance, it is relevant to summarize the evidence and determine the effects across different original articles. This systematic review with meta-analysis was conducted to assess the effects of PJT programs on dynamic and static balance in soccer players. The data sources utilized were Cochrane, Medline (PubMed), SPORTDiscus, and Web of Science. (i) Soccer players of any age or sex without injury, illness, or other clinical conditions; (ii) PJT-based programs restricted to a minimum of three weeks (duration); (iii) passive or active control groups; (iv) pre-post interventions values of dynamic and/or static balance; (v) randomized-controlled trials; and (vi) peerreviewed original full-text studies written in English, Portuguese, and/or Spanish. The database search initially identified 803 titles. From those, eight articles were eligible for the systematic review and meta-analysis. The results showed no significant differences between PJT and active controls in dynamic anterior, postero-medial, or postero-lateral balance for both left and right legs (p > 0.05). Additionally, no significant differences were found between PJT and active controls in terms of static balance (p = 0.495). The current evidence suggests that PJT has no significant advantage over active control groups in terms of dynamic or static balance. 相似文献
95.
Integrating correlation between traits improves spatial predictions of plant functional composition
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Rafael O. Wüest Tamara Münkemüller Sébastien Lavergne Laura J. Pollock Wilfried Thuiller 《Oikos》2018,127(3):472-481
Functional trait composition is increasingly recognized as key to better understand and predict community responses to environmental gradients. Predictive approaches traditionally model the weighted mean trait values of communities (CWMs) as a function of environmental gradients. However, most approaches treat traits as independent regardless of known tradeoffs between them, which could lead to spurious predictions. To address this issue, we suggest jointly modeling a suit of functional traits along environmental gradients while accounting for relationships between traits. We use generalized additive mixed effect models to predict the functional composition of alpine grasslands in the Guisane Valley (France). We demonstrate that, compared to traditional approaches, joint trait models explain considerable amounts of variation in CWMs, yield less uncertainty in trait CWM predictions and provide more realistic spatial projections when extrapolating to novel environmental conditions. Modeling traits and their co‐variation jointly is an alternative and superior approach to predicting traits independently. Additionally, compared to a ‘predict first, assemble later’ approach that estimates trait CWMs post hoc based on stacked species distribution models, our ‘assemble first, predict later’ approach directly models trait‐responses along environmental gradients, and does not require data and models on species’ distributions, but only mean functional trait values per community plot. This highlights the great potential of joint trait modeling approaches in large‐scale mapping applications, such as spatial projections of the functional composition of vegetation and associated ecosystem services as a response to contemporary global change. 相似文献
96.
The lymphocyte receptor CD6 interacts with syntenin-1, a scaffolding protein containing PDZ domains 总被引:3,自引:0,他引:3
Gimferrer I Ibáñez A Farnós M Sarrias MR Fenutría R Roselló S Zimmermann P David G Vives J Serra-Pagès C Lozano F 《Journal of immunology (Baltimore, Md. : 1950)》2005,175(3):1406-1414
CD6 is a type I membrane glycoprotein expressed on thymocytes, mature T and B1a lymphocytes, and CNS cells. CD6 binds to activated leukocyte cell adhesion molecule (CD166), and is considered as a costimulatory molecule involved in lymphocyte activation and thymocyte development. Accordingly, CD6 partially associates with the TCR/CD3 complex and colocalizes with it at the center of the mature immunological synapse (IS) on T lymphocytes. However, the signaling pathway used by CD6 is still mostly unknown. The yeast two-hybrid system has allowed us the identification of syntenin-1 as an interacting protein with the cytoplasmic tail of CD6. Syntenin-1 is a PDZ (postsynaptic density protein-95, postsynaptic discs large, and zona occludens-1) domain-containing protein, which functions as an adaptor protein able to bind cytoskeletal proteins and signal transduction effectors. Mutational analyses showed that certain amino acids of the most C-terminal sequence of CD6 (-YDDISAA) and the two postsynaptic density protein-95, postsynaptic discs large, and zona occludens-1 domains of syntenin-1 are relevant to the interaction. Further confirmation of the CD6-syntenin-1 interaction was obtained from pull-down and co-immunoprecipitation assays in mammalian cells. Image analyses also showed that syntenin-1 accumulates at CD6 caps and at the IS. Therefore, we propose that syntenin-1 may function as a scaffolding protein coupling CD6 and most likely other lymphocyte receptors to cytoskeleton and/or signaling effectors during IS maturation. 相似文献
97.
María C.ESCALA 《动物学报》2008,54(4)
1996-1998年8月在Larraun河(埃布罗河流域,西班牙北部)共捕获306尾埃布罗河(鱼岁)和185尾0龄的鳟,分析比较了胃含物组成,并测定了种间的食物重叠.食物的个数百分比组成表明两种都主要摄食水生无脊椎动物.摄食策略图显示两种都是摄食不同食物 种类的广食性种类.另外,比较胃含物和底栖大型无脊椎动物群落表明,0龄的鳟和埃布罗河(鱼岁)不摄食光螺科、钩虾科、细蜉科、 四节蜉科和卷襀科的物种,而喜食摇蚊科、五节蜉科和毛翅目物种.尽管简化的Morisitas指数表明Larraun河中这两种鱼之间的食物重叠是显著的,但由于栖息地不同和摄食的可塑性可以降低种间的竞争,使得该水域的这两种鱼能以相对较大的数量共存.然而,在食物资源和可用栖息地有限的河域,埃布罗河(鱼岁)的引入,其适应性和可塑性有可能威胁单独存在的鳟 相似文献
98.
Jinbo Pang Alicja Bachmatiuk Yin Yin Barbara Trzebicka Liang Zhao Lei Fu Rafael G. Mendes Thomas Gemming Zhongfan Liu Mark H. Rummeli 《Liver Transplantation》2018,8(8)
The successful isolation of phosphorene (atomic layer thick black phosphorus) in 2014 has currently aroused the interest of 2D material researchers. In this review, first, the fundamentals of phosphorus allotropes, phosphorene, and black phosphorus, are briefly introduced, along with their structures, properties, and synthesis methods. Second, the readers are presented with an overview of their energy applications. Particularly in electrochemical energy storage, the large interlayer spacing (0.53 nm) in phosphorene allows the intercalation/deintercalation of larger ions as compared to its graphene counterpart. Therefore, phosphorene may possess greater potential for high electrochemical performance. In addition, the status of lithium ion batteries as well as secondary sodium ion batteries is reviewed. Next, each application for energy generation, conversion, and storage is described in detail with milestones as well as the challenges. These emerging applications include supercapacitors, photovoltaic devices, water splitting, photocatalytic hydrogenation, oxygen evolution, and thermoelectric generators. Finally the fast‐growing dynamic field of phosphorene research is summarized and perspectives on future possibilities are presented calling on the efforts of chemists, physicists, and material scientists 相似文献
99.
Luísa Czamanski Nora Cauã Antunes Westmann María-Eugenia Guazzaroni Chandranayaka Siddaiah Vijai Kumar Gupta Rafael Silva-Rocha 《Biotechnology advances》2019,37(8):107433
A key challenge for domesticating alternative cultivable microorganisms with biotechnological potential lies in the development of innovative technologies. Within this framework, a myriad of genetic tools has flourished, allowing the design and manipulation of complex synthetic circuits and genomes to become the general rule in many laboratories rather than the exception. More recently, with the development of novel technologies such as DNA automated synthesis/sequencing and powerful computational tools, molecular biology has entered the synthetic biology era. In the beginning, most of these technologies were established in traditional microbial models (known as chassis in the synthetic biology framework) such as Escherichia coli and Saccharomyces cerevisiae, enabling fast advances in the field and the validation of fundamental proofs of concept. However, it soon became clear that these organisms, although extremely useful for prototyping many genetic tools, were not ideal for a wide range of biotechnological tasks due to intrinsic limitations in their molecular/physiological properties. Over the last decade, researchers have been facing the great challenge of shifting from these model systems to non-conventional chassis with endogenous capacities for dealing with specific tasks. The key to address these issues includes the generation of narrow and broad host plasmid-based molecular tools and the development of novel methods for engineering genomes through homologous recombination systems, CRISPR/Cas9 and other alternative methods. Here, we address the most recent advances in plasmid-based tools for the construction of novel cell factories, including a guide for helping with “build-your-own” microbial host. 相似文献
100.
Nup358/RanBP2 attaches to the nuclear pore complex via association with Nup88 and Nup214/CAN and plays a supporting role in CRM1-mediated nuclear protein export 总被引:6,自引:0,他引:6
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Bernad R van der Velde H Fornerod M Pickersgill H 《Molecular and cellular biology》2004,24(6):2373-2384
Nuclear pore complexes (NPCs) traverse the nuclear envelope (NE), providing a channel through which nucleocytoplasmic transport occurs. Nup358/RanBP2, Nup214/CAN, and Nup88 are components of the cytoplasmic face of the NPC. Here we show that Nup88 localizes midway between Nup358 and Nup214 and physically interacts with them. RNA interference of either Nup88 or Nup214 in human cells caused a strong reduction of Nup358 at the NE. Nup88 and Nup214 showed an interdependence at the NPC and were not affected by the absence of Nup358. These data indicate that Nup88 and Nup214 mediate the attachment of Nup358 to the NPC. We show that localization of the export receptor CRM1 at the cytoplasmic face of the NE is Nup358 dependent and represents its empty state. Also, removal of Nup358 causes a distinct reduction in nuclear export signal-dependent nuclear export. We propose that Nup358 provides both a platform for rapid disassembly of CRM1 export complexes and a binding site for empty CRM1 recycling into the nucleus. 相似文献