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1.
Visual processing of objects makes use of both feedforward and feedback streams of information. However, the nature of feedback signals is largely unknown, as is the identity of the neuronal populations in lower visual areas that receive them. Here, we develop a recurrent neural model to address these questions in the context of contour integration and figure-ground segregation. A key feature of our model is the use of grouping neurons whose activity represents tentative objects (“proto-objects”) based on the integration of local feature information. Grouping neurons receive input from an organized set of local feature neurons, and project modulatory feedback to those same neurons. Additionally, inhibition at both the local feature level and the object representation level biases the interpretation of the visual scene in agreement with principles from Gestalt psychology. Our model explains several sets of neurophysiological results (Zhou et al. Journal of Neuroscience, 20(17), 6594–6611 2000; Qiu et al. Nature Neuroscience, 10(11), 1492–1499 2007; Chen et al. Neuron, 82(3), 682–694 2014), and makes testable predictions about the influence of neuronal feedback and attentional selection on neural responses across different visual areas. Our model also provides a framework for understanding how object-based attention is able to select both objects and the features associated with them.  相似文献   

2.
The aim of this paper is to investigate the relationship between information and abductive reasoning in the context of problem-solving, focusing on non-human animals. Two questions guide our investigation: (1) What is the relation between information and abductive reasoning in the context of human and non-human animals? (2) Do non-human animals perform discovery based on inferential processes such as abductive reasoning? In order to answer these questions, we discuss the semiotic concept of information in relation to the concept of abductive reasoning and, more specifically, to the notion of manipulative abduction proposed by Magnani (2009). Finally, we investigate a case study of corvids’ intelligence, namely, their capacity of causal cognition.  相似文献   

3.
In this paper, we study the distribution of the feminine singular suffixes -et and -a in the present tense of Hebrew verb paradigms. The question we ask is which of these two suffixes is the default allomorph. The answer is not trivial. In terms of distribution, -a appears with limited environments and -et is clearly the elsewhere case, and thus the default. In terms of order, however, -et is the feminine singular suffix associated with the present tense, while -a emerges only when -et is blocked. We thus argue for multiple defaults, distinguishing between local and global default; -et is the local default, uniquely associated with feminine singular verbs in the present tense, while -a is the global default, associated with feminine singular but not specified for the present tense. We provide a formal analysis for the distribution of these suffixes within the framework of Optimality Theory, which allows the interaction of phonological constraints with constraints on morpho-syntactic feature mapping. We further study the partially unpredictable distribution of -et and -a in vowel final verbs, and present the results of an experiment where speakers employed unique strategies in order to assign the local default -et.  相似文献   

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6.
The aim of this work was to study the biodiversity of yeasts isolated from the autochthonous grape variety called “Uva di Troia”, monitoring the natural diversity from the grape berries to wine during a vintage. Grapes were collected in vineyards from two different geographical areas and spontaneous alcoholic fermentations (AFs) were performed. Different restriction profiles of ITS–5.8S rDNA region, corresponding to Saccharomyces cerevisiae, Issatchenkia orientalis, Metschnikowia pulcherrima, Hanseniaspora uvarum, Candida zemplinina, Issatchenkia terricola, Kluyveromyces thermotolerans, Torulaspora delbrueckii, Metschnikowia chrysoperlae, Pichia fermentans, Hanseniaspora opuntiae and Hanseniaspora guilliermondii, were observed. The yeast occurrences varied significantly from both grape berries and grape juices, depending on the sampling location. Furthermore, samples collected at the end of AF revealed the great predominance of Saccharomyces cerevisiae, with a high intraspecific biodiversity. This is the first report on the population dynamics of ‘cultivable’ microbiota diversity of “Uva di Troia” cultivar from the grape to the corresponding wine (“Nero di Troia”), and more general for Southern Italian oenological productions, allowing us to provide the basis for an improved management of wine yeasts (with both non-Saccharomyces and Saccharomyces) for the production of typical wines with desired unique traits. A certain geographical-dependent variability has been reported, suggesting the need of local based formulation for autochthonous starter cultures, especially in the proportion of the different species/strains in the design of mixed microbial preparations.  相似文献   

7.
Fossiliferous Quaternary sedimentary beds in the Santa Lucía Basin (southern Uruguay) are potentially useful for the study of the last occurrences of extinct taxa, as well as the environmental and climatic patterns in the late Pleistocene to the early Holocene. They have provided a chronological framework (AMS 14C and Optically Stimulated Luminescence dates), a mammalian diversity and interpretations of last occurrence, the climatic-environmental setting, and some associated biogeographic processes. The ages produced encompass the last 30 to 7 ka interval (latest Pleistocene-early Holocene). The mammalian assemblage (36 genera, 24 species) includes typical South American late Pleistocene mammals, extinct species of extant genera, and some extant species that still exist elsewhere on the continent. The preservation pattern includes articulated and semi-articulated skeletons of large and small mammals. The presence in the southern Uruguayan Pampean area of some mammals currently inhabiting Patagonia, northwest and central Argentina (Dolichotis, Galea, Microcavia, Chaetophractus, Lagostomus, and Vicugna) is explained by the predominance of open areas and cold climates associated with the Last Glacial Maximum. The mammalian record depicts local extinctions or shifting ranges occurring in latest Pleistocene or early Holocene. The sedimentary chronological framework and taphonomic features suggest the persistence into the early Holocene of Eutatus seguini, Morenelaphus brachyceros, Equus neogeus, Hemiauchenia sp., Lama sp., and Vicugna sp. Glyptodon and Glossotherium seem to persist at least to the latest Pleistocene. This pattern can substantiate the hypothesis that some megafauna and large mammals persisted for some millennia alongside people with extinction occurring before, during, and after human colonization.  相似文献   

8.

Background

Guided by the Reach, Effectiveness, Adoption, Implementation, and Maintenance (RE-AIM) implementation framework, a National Institutes of Health-sponsored study compared the nurse-administered Tobacco Tactics intervention to usual care. A prior paper describes the effectiveness of the Tobacco Tactics intervention. This subsequent paper provides data describing the remaining constructs of the RE-AIM framework.

Methods

This pragmatic study used a mixed methods, quasi-experimental design in five Michigan community hospitals of which three received the nurse-administered Tobacco Tactics intervention and two received usual care. Nurses and patients were surveyed pre- and post-intervention.Measures included reach (patient participation rates, characteristics, and receipt of services), adoption (nurse participation rates and characteristics), implementation (pre-to post-training changes in nurses' attitudes, delivery of services, barriers to implementation, opinions about training, documentation of services, and numbers of volunteer follow-up phone calls), and maintenance (continuation of the intervention once the study ended).

Results

Reach: Patient participation rates were 71.5 %. Compared to no change in the control sites, there were significant pre- to post-intervention increases in self-reported receipt of print materials in the intervention hospitals (n?=?1370, p?<?0.001). Adoption: In the intervention hospitals, all targeted units and several non-targeted units participated; 76.0 % (n?=?1028) of targeted nurses and 317 additional staff participated in the training, and 92.4 % were extremely or somewhat satisfied with the training. Implementation: Nurses in the intervention hospitals reported increases in providing advice to quit, counseling, medications, handouts, and DVD (all p?<?0.05) and reported decreased barriers to implementing smoking cessation services (p?<?0.001). Qualitative comments were very positive (“user friendly,” “streamlined,” or “saves time”), although problems with showing patients the DVD and charting in the electronic medical record were noted. Maintenance: Nurses continued to provide the intervention after the study ended.

Conclusions

Given that nurses represent the largest group of front-line providers, this intervention, which meets Joint Commission guidelines for treating inpatient smokers, has the potential to have a wide reach and to decrease smoking, morbidity, and mortality among inpatient smokers. As we move toward more population-based interventions, the RE-AIM framework is a valuable guide for implementation.

Trial registration

ClinicalTrials.gov, NCT01309217
  相似文献   

9.
Temnomastax spielmanni Olivier, 2014 n. syn. is proposed as new synonym of Eumastacops nemorivaga Rehn & Rehn, 1942. New distribution records in Peru and Colombia are provided for the following four species: Eumastax nigrovittata Descamps, 1979; Paramastax nigra (Scudder, 1875); Pseudomastax nigroplagiata Descamps, 1970; and Pseudomastax personata (Bolívar, 1881). New information on the distribution of Paramastax flavovittata Descamps, 1973 and E. nemorivaga is added, resulting in the expansion of the geographic distribution. Photographs of all studied species are provided.  相似文献   

10.

Background

Although the importance of evaluating implementation fidelity is acknowledged, little is known about heterogeneity in fidelity over time. This study aims to generate insight into the heterogeneity in implementation fidelity trajectories of a health promotion program in multidisciplinary settings and the relationship with changes in patients’ health behavior.

Methods

This study used longitudinal data from the nationwide implementation of an evidence-informed physical activity promotion program in Dutch rehabilitation care. Fidelity scores were calculated based on annual surveys filled in by involved professionals (n?=?±?70). Higher fidelity scores indicate a more complete implementation of the program’s core components. A hierarchical cluster analysis was conducted on the implementation fidelity scores of 17 organizations at three different time points. Quantitative and qualitative data were used to explore organizational and professional differences between identified trajectories. Regression analyses were conducted to determine differences in patient outcomes.

Results

Three trajectories were identified as the following: ‘stable high fidelity’ (n?=?9), ‘moderate and improving fidelity’ (n?=?6), and ‘unstable fidelity’ (n?=?2). The stable high fidelity organizations were generally smaller, started earlier, and implemented the program in a more structured way compared to moderate and improving fidelity organizations. At the implementation period’s start and end, support from physicians and physiotherapists, professionals’ appreciation, and program compatibility were rated more positively by professionals working in stable high fidelity organizations as compared to the moderate and improving fidelity organizations (p?<?.05). Qualitative data showed that the stable high fidelity organizations had often an explicit vision and strategy about the implementation of the program. Intriguingly, the trajectories were not associated with patients’ self-reported physical activity outcomes (adjusted model β?=???651.6, t(613)?=???1032, p?=?.303).

Conclusions

Differences in organizational-level implementation fidelity trajectories did not result in outcome differences at patient-level. This suggests that an effective implementation fidelity trajectory is contingent on the local organization’s conditions. More specifically, achieving stable high implementation fidelity required the management of tensions: realizing a localized change vision, while safeguarding the program’s standardized core components and engaging the scarce physicians throughout the process. When scaling up evidence-informed health promotion programs, we propose to tailor the management of implementation tensions to local organizations’ starting position, size, and circumstances.

Trial registration

The Netherlands National Trial Register NTR3961. Registered 18 April 2013.
  相似文献   

11.
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Understanding the dynamics of metapopulations close to extinction is of vital importance for management. Levins-like models, in which local patches are treated as either occupied or empty, have been used extensively to explore the extinction dynamics of metapopulations, but they ignore the important role of local population dynamics. In this paper, we consider a stochastic metapopulation model where local populations follow a stochastic, density-dependent dynamics (the Ricker model), and use this framework to investigate the behaviour of the metapopulation on the brink of extinction. We determine under which circumstances the metapopulation follows a time evolution consistent with Levins’ dynamics. We derive analytical expressions for the colonisation and extinction rates (c and e) in Levins-type models in terms of reproduction, survival and dispersal parameters of the local populations, providing an avenue to parameterising Levins-like models from the type of information on local demography that is available for a number of species. To facilitate applying our results, we provide a numerical algorithm for computing c and e.  相似文献   

13.

Background

The goal of personalized medicine is to provide patients optimal drug screening and treatment based on individual genomic or proteomic profiles. Reverse-Phase Protein Array (RPPA) technology offers proteomic information of cancer patients which may be directly related to drug sensitivity. For cancer patients with different drug sensitivity, the proteomic profiling reveals important pathophysiologic information which can be used to predict chemotherapy responses.

Results

The goal of this paper is to present a framework for personalized medicine using both RPPA and drug sensitivity (drug resistance or intolerance). In the proposed personalized medicine system, the prediction of drug sensitivity is obtained by a proposed augmented naive Bayesian classifier (ANBC) whose edges between attributes are augmented in the network structure of naive Bayesian classifier. For discriminative structure learning of ANBC, local classification rate (LCR) is used to score augmented edges, and greedy search algorithm is used to find the discriminative structure that maximizes classification rate (CR). Once a classifier is trained by RPPA and drug sensitivity using cancer patient samples, the classifier is able to predict the drug sensitivity given RPPA information from a patient.

Conclusion

In this paper we proposed a framework for personalized medicine where a patient is profiled by RPPA and drug sensitivity is predicted by ANBC and LCR. Experimental results with lung cancer data demonstrate that RPPA can be used to profile patients for drug sensitivity prediction by Bayesian network classifier, and the proposed ANBC for personalized cancer medicine achieves better prediction accuracy than naive Bayes classifier in small sample size data on average and outperforms other the state-of-the-art classifier methods in terms of classification accuracy.
  相似文献   

14.
15.
Salt stress is considered one of the main abiotic factors to limit crop growth and productivity by affecting morpho-physiological and biochemical processes. Genetically, a number of salt tolerant Brassica varieties have been developed and introduced, but breeding of such varieties is time consuming. Therefore, current focus is on transgenic technology, which plays an important role in the development of salt tolerant varieties. Various salt tolerant genes have been characterized and incorporated into Brassica. Therefore, such genetic transformation of Brassica species is a significant step for improvement of crops, as well as conferring salt stress resistance qualities to Brassica species. Complete genome sequencing has made the task of genetically transforming Brassica species easier, by identifying desired candidate genes. The present review discusses relevant information about the principles which should be employed to develop transgenic Brassica species, and also will recommend tools for improved tolerance to salinity.  相似文献   

16.

Background

The methanol-regulated AOX1 promoter (PAOX1) is the most widely used promoter in the production of recombinant proteins in the methylotrophic yeast Pichia pastoris. However, as the tight regulation and methanol dependence of PAOX1 restricts its application, it is necessary to develop a flexible induction system to avoid the problems of methanol without losing the advantages of PAOX1. The availability of synthetic biology tools enables researchers to reprogram the cellular behaviour of P. pastoris to achieve this goal.

Results

The characteristics of PAOX1 are highly related to the expression profile of methanol expression regulator 1 (Mxr1). In this study, we applied a biologically inspired strategy to reprogram regulatory networks in P. pastoris. A reprogrammed P. pastoris was constructed by inserting a synthetic positive feedback circuit of Mxr1 driven by a weak AOX2 promoter (PAOX2). This novel approach enhanced PAOX1 efficiency by providing extra Mxr1 and generated switchable Mxr1 expression to allow PAOX1 to be induced under glycerol starvation or carbon-free conditions. Additionally, the inhibitory effect of glycerol on PAOX1 was retained because the synthetic circuit was not activated in response to glycerol. Using green fluorescent protein as a demonstration, this reprogrammed P. pastoris strain displayed stronger fluorescence intensity than non-reprogrammed cells under both methanol induction and glycerol starvation. Moreover, with single-chain variable fragment (scFv) as the model protein, increases in extracellular scFv productivity of 98 and 269% were observed in Mxr1-reprogrammed cells under methanol induction and glycerol starvation, respectively, compared to productivity in non-reprogrammed cells under methanol induction.

Conclusions

We successfully demonstrate that the synthetic positive feedback circuit of Mxr1 enhances recombinant protein production efficiency in P. pastoris and create a methanol-free induction system to eliminate the potential risks of methanol.
  相似文献   

17.

Backgrounds

A large number of long intergenic non-coding RNAs (lincRNAs) are linked to a broad spectrum of human diseases. The disease association with many other lincRNAs still remain as puzzle. Validation of such links between the two entities through biological experiments are expensive. However, a plethora lincRNA-data are available now, thanks to the High Throughput Sequencing (HTS) platforms, Genome Wide Association Studies (GWAS), etc, which opens the opportunity for cutting-edge machine learning and data mining approaches to extract meaningful relationships among lincRNAs and diseases. However, there are only a few in silico lincRNA-disease association inference tools available to date, and none of them utilizes side information of both the entities simultaneously in a single framework.

Methods

The recently developed Inductive Matrix Completion (IMC) technique provides a recommendation platform among two entities considering respective side information about them. However, the formulation of IMC is incapable of handling noise and outliers that may be present in the datasets, while data sparsity consideration is another issue with the standard IMC method. Thus, a robust version of IMC is needed that can solve the two issues. As a remedy, in this paper, we propose Stable Robust Inductive Matrix Completion (SRIMC) that utilizes the l 2,1 norm based regularization to optimize the objective function with a unique 2-step stable solution approach.

Results

We applied SRIMC to the available association data between human lincRNAs and OMIM disease phenotypes as well as a diverse set of side information about the lincRNAs and the diseases. The method performs better than the state-of-the-art methods in terms of p r e c i s i o n @ k and r e c a l l @ k at the top-k disease prioritization to the subject lincRNAs. We also demonstrate that SRIMC is equally effective for querying about novel lincRNAs, as well as predicting rank of a newly known disease for a set of well-characterized lincRNAs.

Conclusions

With the experimental results and computational evaluation, we show that SRIMC is robust in handling datasets with noise and outliers as well as dealing with novel lincRNAs and disease phenotypes.
  相似文献   

18.
Primates play a fundamental role as seed dispersers, particularly in tropical rainforests. Because defaunation and fragmentation are leading several primate species to local extinction, it is fundamental to understand the role of primates as effective seed dispersers. Here we present a systematic review of studies of seed dispersal by primates in a biodiversity hotspot, the Atlantic Forest of South America, to 1) highlight gaps in our knowledge, 2) determine species richness and proportion of seed species dispersed, and 3) test the relationship between primate body size and the size of dispersed species. Our review found 79 studies of the diet of six ecospecies (Callithrix, Leontopithecus, Callicebus, Sapajus, Alouatta, Brachyteles) but only 20 of these report information on seed dispersal, and none of these are on Callithrix or Callicebus. We found a strong bias in the distribution of species and regions, with most of the studies concentrated in southeastern Brazil. All ecospecies dispersed a large proportion of the seed species they handled (72.1–93.6%). Brachyteles dispersed the highest diversity of plants (N = 73), followed by Sapajus (N = 66), Leontopithecus (N = 49), and Alouatta (N = 26). Although we found no significant relationship between primate body size and the size of seeds dispersed, Brachyteles disperse a higher diversity of large-seeded species than smaller-bodied primates. These results suggest that the local extinction of large primate species may lead to dramatic changes in the plant community, as many large-seeded plants are inaccessible to smaller arboreal frugivores. We propose guidelines for future research on primate seed dispersal to enable the evaluation of seed dispersal effectiveness and to improve our understanding of the fundamental role of primates in this key ecosystem process.  相似文献   

19.

Background

Over the past years, implementation science has gained more and more importance in German-speaking countries. Reliable and valid questionnaires are needed for evaluating the implementation of evidence-based practices. On an international level, several initiatives focused on the identification of questionnaires used in English-speaking countries but limited their search processes to mental health and public health settings. Our aim was to identify questionnaires used in German-speaking countries measuring the implementation of interventions in public health and health care settings in general and to assess their psychometric properties.

Methods

We searched five different bibliographic databases (from 1985 to August 2017) and used several other search strategies (e.g., reference lists, forward citation) to obtain our data. We assessed the instruments, which were identified in an independent dual review process, using 12 psychometric rating criteria. Finally, we mapped the instruments’ scales and subscales in regard to the constructs of the Consolidated Framework for Implementation Research (CFIR) and the Implementation Outcome Framework (IOF).

Results

We identified 31 unique instruments available for the assessment of implementation science constructs. Hospitals and other health care settings were the ones most often investigated (23 instruments), while education and childcare settings, workplace settings, and community settings lacked published instruments. Internal consistency, face and content validity, usability, and structural validity were the aspects most often described. However, most studies did not report on test-retest reliability, known-groups validity, predictive criterion validity, or responsiveness. Overall, the majority of studies did not reveal high-quality instruments, especially regarding the psychometric criteria internal consistency, structural validity, and criterion validity. In addition, we seldom detected instruments operationalizing the CFIR domains intervention characteristics, outer setting, and process, and the IOF constructs adoption, fidelity, penetration, and sustainability.

Conclusions

Overall, a sustained and continuous effort is needed to improve the reliability and validity of existing instruments to new ones. Instruments applicable to the assessment of implementation constructs in public health and community settings are urgently needed.

Trial registration

The systematic review protocol was registered in PROSPERO on October 19, 2017, under the following number: CRD42017075208.
  相似文献   

20.
In this paper, all known autoecious Puccinia species (rust fungi, Uredinales) on Cucurbitaceae are described and most of them illustrated. A key and information on their host range and distribution is presented. Four species, Puccinia antennata, P. arbor-miraculensis, P. hieroglyphica, and P. rhytidioderma are proposed as new. P. momordicae and P. trochomeriae are recognised as valid species different from P. cephalandrae. Uredo melothriae is a new combination for Uromyces melothriae. P. cucumeris is a new report for Namibia, P. momordicae for Zimbabwe and P. vanderystii for Kenya. The species appear to be host specific with regard to host tribes, but P. citrulli and P. cucumeris may pass tribal boundaries. Most species are morphologically very similar and are characterised by a unique set of teliospore characters. They are therefore regarded as a natural group. The distribution of this group in semiarid habitats, mainly from southern Africa to India, is discussed.  相似文献   

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