On the role of feature and signal selection for terrain learning in planetary exploration robots

2021 ◽  
Author(s):  
Angelo Ugenti ◽  
Fabio Vulpi ◽  
Raúl Domínguez ◽  
Florian Cordes ◽  
Annalisa Milella ◽  
...  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Yunqi Bu ◽  
Johannes Lederer

Abstract Graphical models such as brain connectomes derived from functional magnetic resonance imaging (fMRI) data are considered a prime gateway to understanding network-type processes. We show, however, that standard methods for graphical modeling can fail to provide accurate graph recovery even with optimal tuning and large sample sizes. We attempt to solve this problem by leveraging information that is often readily available in practice but neglected, such as the spatial positions of the measurements. This information is incorporated into the tuning parameter of neighborhood selection, for example, in the form of pairwise distances. Our approach is computationally convenient and efficient, carries a clear Bayesian interpretation, and improves standard methods in terms of statistical stability. Applied to data about Alzheimer’s disease, our approach allows us to highlight the central role of lobes in the connectivity structure of the brain and to identify an increased connectivity within the cerebellum for Alzheimer’s patients compared to other subjects.


2015 ◽  
Vol 22 (6) ◽  
pp. T177-T186 ◽  
Author(s):  
Bruno M Simões ◽  
Denis G Alferez ◽  
Sacha J Howell ◽  
Robert B Clarke

Breast cancer stem cells (BCSCs) are potent tumor-initiating cells in breast cancer, the most common cancer among women. BCSCs have been suggested to play a key role in tumor initiation which can lead to disease progression and formation of metastases. Moreover, BCSCs are thought to be the unit of selection for therapy-resistant clones since they survive conventional treatments, such as chemotherapy, irradiation, and hormonal therapy. The importance of the role of hormones for both normal mammary gland and breast cancer development is well established, but it was not until recently that the effects of hormones on BCSCs have been investigated. This review will discuss recent studies highlighting how ovarian steroid hormones estrogen and progesterone, as well as therapies against them, can regulate BCSC activity.


Behaviour ◽  
2011 ◽  
Vol 148 (11-13) ◽  
pp. 1372-1392 ◽  
Author(s):  
Alice U. Edler ◽  
Thomas W.P. Friedl

AbstractThe role of bright plumage colouration for female choice has been the focus of research in sexual selection for many years, with several studies showing that females prefer the most elaborately ornamented males, which are often also the highest quality individuals. Here, we analysed the associations between reproductive performance and plumage, body condition and blood parasite load in the red bishop (Euplectes orix), a sexually dimorphic and polygynous weaverbird species, where males in a carotenoid-based orange-to-red breeding plumage defend territories and build many nests to which they try to attract females. Male reproductive success in terms of number of nests accepted was mainly determined by the number of nests built, but was also positively related to blood parasite load, while we found no influence of plumage characteristics. Together with previously obtained data, our results indicate that plumage characteristics in the red bishop do not affect male reproductive success and are generally not suitable to reliably indicate male quality. We suggest that the primary function of the brilliant orange-scarlet breeding plumage might be presence signalling in terms of increasing conspicuousness of breeding males to females searching for mates.


Author(s):  
André Moreira de Assis ◽  
Airton Mota Moreira ◽  
Francisco Cesar Carnevale ◽  
Antonio Sergio Zafred Marcelino ◽  
Alberto Azoubel Antunes ◽  
...  

Physiology ◽  
2021 ◽  
Vol 36 (5) ◽  
pp. 324-330 ◽  
Author(s):  
Scott M. Smith ◽  
Sara R. Zwart

History books are rife with examples of the role of nutrition in determining either the success or the failure of human exploration on Earth. With planetary exploration in our future, it is imperative that we understand the role of nutrition in optimizing health before humans can safely take the next giant leaps in space exploration.


2015 ◽  
Vol 82 (2) ◽  
Author(s):  
Barbara Bordoni ◽  
Stefano Urbinati ◽  
Alicia Tosoni ◽  
Graziana Labanti ◽  
Alba Brandes

Life expectancy in patients affected by cancer has recently increased because of early diagnosis and actual therapies. In recent years, Oncology and Cardiology developed a tight relationship because of common risk factors (i.e. obesity, smoking, alcool intake, etc…), and for preventing the prothrombotic status due to cancer and the potential cardiotoxicity of chemotherapy. Cardiotoxicity incidence is reported from 1% up to 70% in retrospective analyses of drug protocols, mainly representing by left ventricular dysfunction (both reversible or irreversible), but also by arrhythmias, hypertension, atrioventricular block, coronary spasm, and arterial or venous thromboembolism. The early detection of the chemoterapy induced cardiotoxicity is now mandatory and can be obtained through a proper patients selection for different treatments and a strict monitoring during the follow-up period. The role of biomarkers of early cardiac damage, mainly, troponin I and brain natriuretic peptide-BNP, has been recently challenged, and algorithms are currently available. In the present paper, we propose how to perform a cardiological evaluation of patients undergoing chemoterapy tailored by the known adverse effects of the drugs.


2018 ◽  
Vol 285 (1885) ◽  
pp. 20181164 ◽  
Author(s):  
Philip A. Downing ◽  
Ashleigh S. Griffin ◽  
Charlie K. Cornwallis

The evolution of helping behaviour in species that breed cooperatively in family groups is typically attributed to kin selection alone. However, in many species, helpers go on to inherit breeding positions in their natal groups, but the extent to which this contributes to selection for helping is unclear as the future reproductive success of helpers is often unknown. To quantify the role of future reproduction in the evolution of helping, we compared the helping effort of female and male retained offspring across cooperative birds. The kin selected benefits of helping are equivalent between female and male helpers—they are equally related to the younger siblings they help raise—but the future reproductive benefits of helping differ because of sex differences in the likelihood of breeding in the natal group. We found that the sex which is more likely to breed in its natal group invests more in helping, suggesting that in addition to kin selection, helping in family groups is shaped by future reproduction.


2009 ◽  
Vol 276 (1664) ◽  
pp. 1971-1980 ◽  
Author(s):  
J. Jordan Price ◽  
Scott M. Lanyon ◽  
Kevin E. Omland

Birds in which both sexes produce complex songs are thought to be more common in the tropics than in temperate areas, where typically only males sing. Yet the role of phylogeny in this apparent relationship between female song and latitude has never been examined. Here, we reconstruct evolutionary changes in female song and breeding latitude in the New World blackbirds (Icteridae), a family with both temperate and tropical representatives. We provide strong evidence that members of this group have moved repeatedly from tropical to temperate breeding ranges and, furthermore, that these range shifts were associated with losses of female song more often than expected by chance. This historical perspective suggests that male-biased song production in many temperate species is the result not of sexual selection for complex song in males but of selection against such songs in females. Our results provide new insights into the differences we see today between tropical and temperate songbirds, and suggest that the role of sexual selection in the evolution of bird song might not be as simple as we think.


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