Search results for "Selection"

The impact of life stage and pigment source on the evolution of novel warning signal traits

2021

Our understanding of how novel warning color traits evolve in natural populations is largely based on studies of reproductive stages and organisms with endogenously produced pigmentation. In these systems, genetic drift is often required for novel alleles to overcome strong purifying selection stemming from frequency-dependent predation and positive assortative mating. Here, we integrate data from field surveys, predation experiments, population genomics, and phenotypic correlations to explain the origin and maintenance of geographic variation in a diet-based larval pigmentation trait in the redheaded pine sawfly (Neodiprion lecontei), a pine-feeding hymenopteran. Although our experiments c…

Diversity in warning coloration: selective paradox or the norm?

2019

Aposematic theory has historically predicted that predators should select for warning signals to converge on a single form, as a result of frequency-dependent learning. However, widespread variation in warning signals is observed across closely related species, populations and, most problematically for evolutionary biologists, among individuals in the same population. Recent research has yielded an increased awareness of this diversity, challenging the paradigm of signal monomorphy in aposematic animals. Here we provide a comprehensive synthesis of these disparate lines of investigation, identifying within them three broad classes of explanation for variation in aposematic warning signals: …

Multimodal Aposematic Signals and Their Emerging Role in Mate Attraction

2018

Generating TV summaries for CE-devices

2002

Automatically generated summaries of TV content are indispensable for content selection and navigation in CE-devices. We show two different types of summaries: Short video trailers and visual overviews consisting of representative frames. The demo does not only show the feasibility of the proposed algorithms, but also shows how different types of generated summaries can be used in future CE-devices.

Spatiotemporal and gender‐specific parasitism in two species of gobiid fish

2018

Abstract Parasitism is considered a major selective force in natural host populations. Infections can decrease host condition and vigour, and potentially influence, for example, host population dynamics and behavior such as mate choice. We studied parasite infections of two common marine fish species, the sand goby (Pomatoschistus minutus) and the common goby (Pomatoschistus microps), in the brackish water Northern Baltic Sea. We were particularly interested in the occurrence of parasite taxa located in central sensory organs, such as eyes, potentially affecting fish behavior and mate choice. We found that both fish species harbored parasite communities dominated by taxa transmitted to fish…

Oikealle alalle? : logistiikka-alan ammattikoulutuksen ja työelämän osaamisen todellisuuksien kohtaaminen

2016

The aim of this doctoral thesis was to study how vocational education and training (VET) and working life encounter each other. Naturally the research topic chosen was selected from the researcher´s own professional field, i.e., logistics education. The research task was to examine, how VET-students' professional expectations in the study field of logistics encounter with the working life realities. The main research question was “How do the logistics (driver training) students’ vocational expectations encounter with the requirements of dynamically changing working life from the point of view of the vocational competence, the time span of 2001-2025?” The two sub-questions were 1) How do the…

Anomaly detection using one-class SVM with wavelet packet decomposition

2011

Anomaly detection has become a popular research topic in the field of machine learning. Support vector machine is one anomaly detection technique and it is coming one the most widely used. In this research, anomaly detection is applied to road condition monitoring, especially pothole detection, using accelerometer data. The proposed concept includes data preprocessing, feature extraction, feature selection and classification. Accelerometer data was first filtered and segmented, after which features were extracted with frequency- and time-domain functions, with genetic programming and with wavelet packet decomposition. A classification model was built using support vector machine and the cal…

Sparsity-aware multiple relay selection in large multi-hop decode-and-forward relay networks

2016

In this paper, we propose and investigate two novel techniques to perform multiple relay selection in large multi-hop decode-and-forward relay networks. The two proposed techniques exploit sparse signal recovery theory to select multiple relays using the orthogonal matching pursuit algorithm and outperform state-of-the-art techniques in terms of outage probability and computation complexity. To reduce the amount of collected channel state information (CSI), we propose a limited-feedback scheme where only a limited number of relays feedback their CSI. Furthermore, a detailed performance-complexity tradeoff investigation is conducted for the different studied techniques and verified by Monte …

XENON1T Dark Matter Data Analysis: Signal Reconstruction, Calibration and Event Selection

2019

The XENON1T experiment at the Laboratori Nazionali del Gran Sasso is the most sensitive direct detection experiment for dark matter in the form of weakly interacting particles (WIMPs) with masses above $6\,$GeV/$c^2$ scattering off nuclei. The detector employs a dual-phase time projection chamber with 2.0 metric tons of liquid xenon in the target. A one metric $\mathrm{ton}\times\mathrm{year}$ exposure of science data was collected between October 2016 and February 2018. This article reports on the performance of the detector during this period and describes details of the data analysis that led to the most stringent exclusion limits on various WIMP-nucleon interaction models to date. In pa…

How Do Young Adults Orchestrate Their Multiple Achievement-Related Goals? Associations of Achievement Goal Orientations With Identity Formation and G…

2016

Young adults strive for multiple achievement goals. Frameworks for achievement goal orientations, personal goals, and identity formation have emphasized the role of goal-specific exploration and commitment in the interpretation of goals. However, researchers have yet to combine these different perspectives in an empirical study. Therefore, to explore the processes involved in the selection of multiple goals, the present study investigated the associations of young adults’ achievement goal orientations (mastery-intrinsic, mastery-extrinsic, performance-approach, performance-avoidance, and work-avoidance orientations) with distinct styles of exploring and committing to goals, by considering d…