148 research outputs found
Ion velocity distributions within the LLBL and their possible implication to multiple reconnections
Qual Ă© o lugar do aluno com deficiĂȘncia? O imaginĂĄrio coletivo de professores sobre a inclusĂŁo escolar
Theory of differential inclusions and its application in mechanics
The following chapter deals with systems of differential equations with
discontinuous right-hand sides. The key question is how to define the solutions
of such systems. The most adequate approach is to treat discontinuous systems
as systems with multivalued right-hand sides (differential inclusions). In this
work three well-known definitions of solution of discontinuous system are
considered. We will demonstrate the difference between these definitions and
their application to different mechanical problems. Mathematical models of
drilling systems with discontinuous friction torque characteristics are
considered. Here, opposite to classical Coulomb symmetric friction law, the
friction torque characteristic is asymmetrical. Problem of sudden load change
is studied. Analytical methods of investigation of systems with such
asymmetrical friction based on the use of Lyapunov functions are demonstrated.
The Watt governor and Chua system are considered to show different aspects of
computer modeling of discontinuous systems
Hot flow anomalies at Venus
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95474/1/jgra21752.pd
Whole-exome sequencing uncovers frequent GNAS mutations in intraductal papillary mucinous neoplasms of the pancreas
Intraductal papillary mucinous neoplasm (IPMN) is a common pancreatic cystic neoplasm that
is often invasive and metastatic, resulting in a poor prognosis. Few molecular alterations
unique to IPMN are known. We performed whole-exome sequencing for a primary IPMN tissue,
which uncovered somatic mutations in KCNF1, DYNC1H1, PGCP, STAB1, PTPRM, PRPF8, RNASE3,
SPHKAP, MLXIPL, VPS13C, PRCC, GNAS, KRAS, RBM10, RNF43, DOCK2, and CENPF. We
further analyzed GNAS mutations in archival cases of 118 IPMNs and 32 pancreatic
ductal adenocarcinomas (PDAs), which revealed that 48 (40.7%) of the 118 IPMNs but none of
the 32 PDAs harbored GNAS mutations. G-protein alpha-subunit encoded by GNAS
and its downstream targets, phosphorylated substrates of protein kinase A, were evidently
expressed in IPMN; the latter was associated with neoplastic grade. These results indicate
that GNAS mutations are common and specific for IPMN, and activation of G-protein
signaling appears to play a pivotal role in IPMN
Venera-D Mission Concept to Study Atmosphere, Surface and Plasma Environment: Phase II Report of the Venera-D Joint Science Definition Team
Venus and Earth were formed approximately the same distance from the Sun, and have almost the same masses and volumes: they should be the most similar pair of planets in the Solar System. A vital, outstanding question is how and when these planets diverged in their atmospheric evolutions. Significantly, recent investigations present evidence for microbial life in Venus' cloud deck. Venus presents us with fundamental questions about the origin and evolution of planetary bodies and life in our Solar System.Venera-D (D stands for the Russian word for "long-lived:" dolgozhivushaya) is a potential mission that would combine simultaneous observations of Venus' atmosphere, plasma environment, and surface to try to answer these essential questions
Plasma transition at the flanks of the Venus ionosheath: Evidence from the Venus Express data
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