The Porcelain Crab Transcriptome and PCAD, the Porcelain Crab Microarray and Sequence Database

BACKGROUND: With the emergence of a completed genome sequence of the freshwater crustacean Daphnia pulex, construction of genomic-scale sequence databases for additional crustacean sequences are important for comparative genomics and annotation. Porcelain crabs, genus Petrolisthes, have been powerful crustacean models for environmental and evolutionary physiology with respect to thermal adaptation and understanding responses of marine organisms to climate change. Here, we present a large-scale EST sequencing and cDNA microarray database project for the porcelain crab Petrolisthes cinctipes. METHODOLOGY/PRINCIPAL FINDINGS: A set of approximately 30K unique sequences (UniSeqs) representing approximately 19K clusters were generated from approximately 98K high quality ESTs from a set of tissue specific non-normalized and mixed-tissue normalized cDNA libraries from the porcelain crab Petrolisthes cinctipes. Homology for each UniSeq was assessed using BLAST, InterProScan, GO and KEGG database searches. Approximately 66% of the UniSeqs had homology in at least one of the databases. All EST and UniSeq sequences along with annotation results and coordinated cDNA microarray datasets have been made publicly accessible at the Porcelain Crab Array Database (PCAD), a feature-enriched version of the Stanford and Longhorn Array Databases. CONCLUSIONS/SIGNIFICANCE: The EST project presented here represents the third largest sequencing effort for any crustacean, and the largest effort for any crab species. Our assembly and clustering results suggest that our porcelain crab EST data set is equally diverse to the much larger EST set generated in the Daphnia pulex genome sequencing project, and thus will be an important resource to the Daphnia research community. Our homology results support the pancrustacea hypothesis and suggest that Malacostraca may be ancestral to Branchiopoda and Hexapoda. Our results also suggest that our cDNA microarrays cover as much of the transcriptome as can reasonably be captured in EST library sequencing approaches, and thus represent a rich resource for studies of environmental genomics

Neuroscience, free will, and responsibility : the current state of play

A number of psychologists and neuroscientists have argued that experimental findings about the psychological basis of human behavior demonstrate that we lack free will, or that it is limited in ways we do not realize. In this chapter, I survey some of the main claims in this literature, with an eye to situating the contributions to come. I examine Benjamin Libet's work on the timing of awareness of action initiation, Daniel Wegner's claim that acting and thinking that one is acting dissociate, and related experimental work, and suggest that the threat to free will is smaller than has often been thought. I then turn to the question whether the brain is deterministic, and situate that question within philosophical debates. From global threats to free will, I move to local threats: the claim that the situationist literature in psychology shows that we lack free will under some circumstances. Finally, I examine recent developments in experimental philosophy, which aim to reveal ordinary people's views on free will.8 page(s

Granular flows at recurring slope lineae on Mars indicate a limited role for liquid water

Recent liquid water flow on Mars has been proposed based on geomorphological features, such as gullies. Recurring slope lineae — seasonal flows that are darker than their surroundings — are candidate locations for seeping liquid water on Mars today, but their formation mechanism remains unclear. Topographical analysis shows that the terminal slopes of recurring slope lineae match the stopping angle for granular flows of cohesionless sand in active Martian aeolian dunes. In Eos Chasma, linea lengths vary widely and are longer where there are more extensive angle-of-repose slopes, inconsistent with models for water sources. These observations suggest that recurring slope lineae are granular flows. The preference for warm seasons and the detection of hydrated salts are consistent with some role for water in their initiation. However, liquid water volumes may be small or zero, alleviating planetary protection concerns about habitable environments

Meaning in life: nature, needs, and myths

The authors first discuss the nature of meaning with a focus on three broad functions of meaning and two levels of meaning. Next, the authors discuss the need for meaning with a focus on the four needs for meaning (Baumeister 1991). Finally, the authors discuss some myths related to meaning, particularly the expectation that everything in life does (or will) make sense and have a reason. Throughout the chapter, the authors discuss ideas where the existential perspective and positive psychology perspective differ and could be integrated. Meaning in life likely serves several different functions. First, meaning helps individuals detect patterns in their environment. Such patterns can exist in the physical or social environment. The second function is communication. The third function is related to self-control. Meaning enables one to refer to cultural standards and think about long-term goals and therefore facilitates self-control. Meaning can exist on multiple levels (Vallacher and Wegner 1985). A high level of meaning involves complex and abstract relationships that span out across a large time frame. A low level of meaning is concrete and is in the present moment. The implications of moving to and from different levels of meaning are also discussed. The authors break down the need for meaning in life into four basic needs: purpose, values, efficacy, and self-worth. If all four needs are satisfied it will engender a sense of meaning in life. If one or more of the four needs is unfulfilled, one will be motivated to adjust their life in such a way that all four needs are covered. These four needs can be seen as unique motivations that facilitate making sense of and finding meaning in life