Sos proteins function as activators of Ras signaling by catalyzing guanine nucleotide exchange on Ras. Sos regulation was initially thought to be accomplished primarily through its growth factor-dependent recruitment to the plasma membrane. More recent data has indicated that while membrane association is an indispensable means of Sos regulation, additional mechanisms involving intramolecular i...

In this work, a new hybrid Symbiotic Organisms Search (SOS) algorithm introduced to design and optimize spatial and planar structures under structural constraints. The SOS algorithm is inspired by the interactive behavior between organisms to propagate in nature. But one of the disadvantages of the SOS algorithm is that due to its vast search space and a large number of organisms, it may trap i...

Many qualitative descriptions of Systems of Systems (SoS) exist in the literature, but only heuristics and guiding principles have been suggested with regard to SoS design methods. To assist SoS designers in decision making during conceptual design, prescriptive design methods are required for SoS. To develop a SoS design method, we propose to build on an existing system tradespace exploration ...

Structured Operational Semantics (SOS) is a popular method for defining semantics by means of deduction rules. An important feature of deduction rules, or simply SOS rules, are negative premises, which are crucial in the definitions of such phenomena as priority mechanisms and time-outs. Orderings on SOS rules were proposed by Phillips and Ulidowski as an alternative to negative premises. The m...

The synergism in anticancer effect toward human renal carcinoma A498 cells by binary combinations of free and N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer-bound anticancer drugs, SOS thiophene (SOS), doxorubicin (DOX), and mesochlorin e6 monoethylenediamine (Mce6), was evaluated. The combination index (CI) analysis was used to quantify the synergism, antagonism, and additive effects. Both...

The purpose of this study is threefold: first, to bring reference groups back into the framework of spiral of silence (SOS) by proposing an extended framework of dual opinion climate; second, to investigate the boundary conditions of SOS; third, to identify the characteristics of SOS in terms of spatial variation and temporal evolution. Modeling SOS with agent-based models, the findings suggest...

The classical model for the activation of the nucleotide exchange factor Son of sevenless (SOS) involves its recruitment to the membrane, where it engages Ras. The recent discovery that Ras*GTP is an allosteric activator of SOS indicated that the regulation of SOS is more complex than originally envisaged. We now present crystallographic and biochemical analyses of a construct of SOS that conta...

System of Systems (SoS) is a subject of interest for many researchers from different research lines. System of Systems Engineering (SoSE) deals with many challenges mainly in the activities related to requirements. In order to explore studies related to Requirements Engineering (RE) for SoS, this Systematic Literature Review, using the Snowballing approach, aims to answer four research question...

Chromosomal DNA is exposed to continuous damage and repair. Cells contain a number of proteins and specific DNA repair systems that help maintain its correct structure. The SOS response was the first DNA repair system described in Escherichia coli induced upon treatment of bacteria with DNA damaging agents arrest DNA replication and cell division. Induction of the SOS response involves more tha...

Regulated activation of Ras by receptor tyrosine kinases (RTK) constitutes a key transduction step in signaling processes that control an array of fundamental cellular functions including proliferation, differentiation, and survival. The principle mechanism by which Ras is activated down stream of RTKs involves the stimulation of guanine nucleotide exchange by the ubiquitous guanine nucleotide ...