A Yap-dependent mechano-regulatory loop directs cell migration for embryo axis assembly

Programa de Doctorado en Biotecnología, Ingeniería y Tecnología QuímicaLínea de Investigación: Biología del DesarrolloClave Programa: DBICódigo Línea: 107Gastrulation is a decisive process that occurs during embryonic development, in which a relatively homogenous group of cells is transformed into an embryo with established body axes and presenting the three germ layers. This is achieved through complex cell rearrangements that are tightly controlled by the interplay of the different types of morphogenetic inputs. In the animal kingdom, striking divergences exist in embryonic development, as they evolve and adapt to different environments, egg architecture and speed of development. However, even though large differences can be found among the different species, the underlying logic and principles governing the gastrulation movements are conserved. The set of cell movements observed during gastrulation is not exclusive to this process, as they are also generally involved in organogenesis, tissue regeneration, and cancer progression. Therefore, understanding how the gastrulation movements are coordinated and controlled is essential not only to understand axis formation, but also how tissues and organs are build, and even which are the mechanism underlying oncogenic growth and metastasis. The key role of mechanical inputs during tissue morphogenesis is becoming increasingly evident, however little is known about how these inputs shape and regulate gastrulation. Among the most well-known transcriptional activators that cells use to interpret mechanical signals are YAP proteins, yet their role in gastrulation remains elusive. Our detailed analysis of yap1 and yap1b double mutants in medaka fish shows that these mechanosensors are required for the assembly of the primary embryo axis: a key event for the establishment of the vertebrate body plan. Using quantitative imaging and live-sensors, we show that Yap activity is required for the proper migration of dorsally converging cells towards the embryo midline. Thus, mutant cells display reduced velocity and migratory persistence resulting in shorter cell displacements in many cases insufficient to reach the midline. Combining RNA-seq with previous DamID-seq data, we characterize the transcriptional program directly activated by Yap proteins, which mostly entails the recruitment of actin cytoskeleton regulators, ECM molecules and focal adhesion components. Moreover, we show that Yap activation depends itself on intracellular tension, closing a positive feedback loop that maintains directed cell migration.Universidad Pablo de Olavide de Sevilla. Departamento de Biología Molecular e Ingeniería Bioquímic

Situated Displays in Telecommunication

In face to face conversation, numerous cues of attention, eye contact, and gaze direction provide important channels of information. These channels create cues that include turn taking, establish a sense of engagement, and indicate the focus of conversation. However, some subtleties of gaze can be lost in common videoconferencing systems, because the single perspective view of the camera doesn't preserve the spatial characteristics of the face to face situation. In particular, in group conferencing, the `Mona Lisa effect' makes all observers feel that they are looked at when the remote participant looks at the camera. In this thesis, we present designs and evaluations of four novel situated teleconferencing systems, which aim to improve the teleconferencing experience. Firstly, we demonstrate the effectiveness of a spherical video telepresence system in that it allows a single observer at multiple viewpoints to accurately judge where the remote user is placing their gaze. Secondly, we demonstrate the gaze-preserving capability of a cylindrical video telepresence system, but for multiple observers at multiple viewpoints. Thirdly, we demonstrated the further improvement of a random hole autostereoscopic multiview telepresence system in conveying gaze by adding stereoscopic cues. Lastly, we investigate the influence of display type and viewing angle on how people place their trust during avatar-mediated interaction. The results show the spherical avatar telepresence system has the ability to be viewed qualitatively similarly from all angles and demonstrate how trust can be altered depending on how one views the avatar. Together these demonstrations motivate the further study of novel display configurations and suggest parameters for the design of future teleconferencing systems

A right hemisphere advantage for processing blurred faces

No description supplie

The LANDSAT Tutorial Workbook: Basics of Satellite Remote Sensing

Most of the subject matter of a full training course in applying remote sensing is presented in a self-teaching mode in this how-to manual which combines a review of basics, a survey of systems, and a treatment of the principles and mechanics of image analysis by computers, with a laboratory approach for learning to utilize the data through practical experiences. All relevant image products are included

The relevance of non-legal technical and scientific concepts in the interpretation and application of the law of the sea : an analysis of the United Nations convention on the law of the sea

Bibliography: p. 363-375.Of necessity LOSC Articles are brief and in some instances vague and requiring interpretation. There is general consensus that LOSC is successful and that its vagueness in certain areas is an asset allowing a variety of otherwise contrary attitudes to be accommodated. 1 It is necessary to analyse the Articles with a view to a better understanding of them and to possibly prepare for some future conference or convention that will more than likely be necessary to resolve some of the remaining problems. To illustrate the need for greater understanding of some of the Articles of LOSC the United Nations Office for Ocean Affairs and Law of the Sea found it necessary to convene a conference of 'experts' during 1993 and 1995 to consider the implications of the complex Articles of LOSC which deal with claims to the continental shelf. Criteria contained in Article 76 allowing for maximum outer limits of the continental shelf and other criteria to justify a claim are complicated and require experience in many fields including marine geology, geography, surveying, and geodesy.2 The intention is therefore to analyse the possible interpretation, application and consequences of the implementation of Articles in LOSC, and more particularly in a Southern African context. Provisions of LOSC, where technical and scientific considerations are crucial, will be selected for consideration. These include those involving geodetic, geographical, geological, survey, navigational, organisational, and social and resource factors

An evaluation of the challenges of Multilingualism in Data Warehouse development

In this paper we discuss Business Intelligence and define what is meant by support for Multilingualism in a Business Intelligence reporting context. We identify support for Multilingualism as a challenging issue which has implications for data warehouse design and reporting performance. Data warehouses are a core component of most Business Intelligence systems and the star schema is the approach most widely used to develop data warehouses and dimensional Data Marts. We discuss the way in which Multilingualism can be supported in the Star Schema and identify that current approaches have serious limitations which include data redundancy and data manipulation, performance and maintenance issues. We propose a new approach to enable the optimal application of multilingualism in Business Intelligence. The proposed approach was found to produce satisfactory results when used in a proof-of-concept environment. Future work will include testing the approach in an enterprise environmen

Television broadcast from space systems: Technology, costs

Broadcast satellite systems are described. The technologies which are unique to both high power broadcast satellites and small TV receive-only earth terminals are also described. A cost assessment of both space and earth segments is included and appendices present both a computer model for satellite cost and the pertinent reported experience with the Japanese BSE

Proceedings of the 5th MIT/ONR Workshop on C[3] Systems, held at Naval Postgraduate School, Monterey, California, August 23 to 27, 1982

"December 1982."Includes bibliographies and index.Office of Naval Research Contract no. ONR/N00014-77-C-0532 NR041-519edited by Michael Athans ... [et al.]

Psr1p interacts with SUN/sad1p and EB1/mal3p to establish the bipolar spindle

Regular Abstracts - Sunday Poster Presentations: no. 382During mitosis, interpolar microtubules from two spindle pole bodies (SPBs) interdigitate to create an antiparallel microtubule array for accommodating numerous regulatory proteins. Among these proteins, the kinesin-5 cut7p/Eg5 is the key player responsible for sliding apart antiparallel microtubules and thus helps in establishing the bipolar spindle. At the onset of mitosis, two SPBs are adjacent to one another with most microtubules running nearly parallel toward the nuclear envelope, creating an unfavorable microtubule configuration for the kinesin-5 kinesins. Therefore, how the cell organizes the antiparallel microtubule array in the first place at mitotic onset remains enigmatic. Here, we show that a novel protein psrp1p localizes to the SPB and plays a key role in organizing the antiparallel microtubule array. The absence of psr1+ leads to a transient monopolar spindle and massive chromosome loss. Further functional characterization demonstrates that psr1p is recruited to the SPB through interaction with the conserved SUN protein sad1p and that psr1p physically interacts with the conserved microtubule plus tip protein mal3p/EB1. These results suggest a model that psr1p serves as a linking protein between sad1p/SUN and mal3p/EB1 to allow microtubule plus ends to be coupled to the SPBs for organization of an antiparallel microtubule array. Thus, we conclude that psr1p is involved in organizing the antiparallel microtubule array in the first place at mitosis onset by interaction with SUN/sad1p and EB1/mal3p, thereby establishing the bipolar spindle.postprin

Removal of antagonistic spindle forces can rescue metaphase spindle length and reduce chromosome segregation defects

Regular Abstracts - Tuesday Poster Presentations: no. 1925Metaphase describes a phase of mitosis where chromosomes are attached and oriented on the bipolar spindle for subsequent segregation at anaphase. In diverse cell types, the metaphase spindle is maintained at a relatively constant length. Metaphase spindle length is proposed to be regulated by a balance of pushing and pulling forces generated by distinct sets of spindle microtubules and their interactions with motors and microtubule-associated proteins (MAPs). Spindle length appears important for chromosome segregation fidelity, as cells with shorter or longer than normal metaphase spindles, generated through deletion or inhibition of individual mitotic motors or MAPs, showed chromosome segregation defects. To test the force balance model of spindle length control and its effect on chromosome segregation, we applied fast microfluidic temperature-control with live-cell imaging to monitor the effect of switching off different combinations of antagonistic forces in the fission yeast metaphase spindle. We show that spindle midzone proteins kinesin-5 cut7p and microtubule bundler ase1p contribute to outward pushing forces, and spindle kinetochore proteins kinesin-8 klp5/6p and dam1p contribute to inward pulling forces. Removing these proteins individually led to aberrant metaphase spindle length and chromosome segregation defects. Removing these proteins in antagonistic combination rescued the defective spindle length and, in some combinations, also partially rescued chromosome segregation defects. Our results stress the importance of proper chromosome-to-microtubule attachment over spindle length regulation for proper chromosome segregation.postprin