Search results for "SCAD"

Ras family genes: An interesting link between cell cycle and cancer

2002

Ras genes are evolutionary conserved and codify for a monomeric G protein binding GTP (active form) or GDP (inactive form). The ras genes are ubiquitously expressed although mRNA analysis suggests different level expression in tissue. Mutations in each ras gene frequently were found in different tumors, suggesting their involvement in the development of specific neoplasia. These mutations lead to a constitutive active and potentially oncogenic protein that could cause a deregulation of cell cycle. Ras protein moderates cellular responses at several mitogens and/or differentiation factors and at external stimuli. These stimuli activate a series of signal transduction pathways that either can…

Diastereoselective Synthesis of Spiro[pyrazolone-4,3′-tetrahydrothiophenes] via a Sulfa-Michael/Aldol Domino Reaction

2016

Synthesis : journal of synthetic organic chemistry 48(23), 4091-4098(2016). doi:10.1055/s-0035-1562473

Understanding the Nature of the Molecular Mechanisms Associated with the Competitive Lewis Acid Catalyzed[4+2] and[4+3] Cycloadditions between Arylid…

2004

The molecular mechanisms of the reactions between aryliden-5(4H)-oxazolone 1, and cyclopentadiene (Cp), in presence of Lewis acid (LA) catalyst to obtain the corresponding [4+2] and [4+3] cycloadducts are examined through density functional theory (DFT) calculations at the B3LYP/6-31G* level. The activation effect of LA catalyst can be reached by two ways, that is, interaction of LA either with carbonyl or carboxyl oxygen atoms of 1 to render [4+2] or [4+3] cycloadducts. The endo and exo [4+2] cycloadducts are formed through a highly asynchronous concerted mechanism associated to a Michael-type addition of Cp to the beta-conjugated position of alpha,beta-unsaturated carbonyl framework of 1.…

Step growth polymerization via tandem ene and diels-alder reactions

1997

In contrast to other electron deficient enophiles or dienophiles which react with 1,4-cyclohexadiene (1,4-CHD) under aromatization, 1,2,4-triazoline-3,5-diones react in a defined reaction sequence. In a first step the 1,4-cyclohexadiene reacts via an ene-reaction. The intermediately formed substituted 1,3-cyclohexadiene immediately reacts in a Diels-Alder reaction. The regiochemistry of the Diels-Alder reaction is controlled by the solvent polarity. This reaction sequence can be used to synthesize polymers. Low-molar-mass model compounds were synthesized to elucidate the stereochemistry of the polymers. By varying the bistriazolinedione, polymers with backbones of different rigidity are ava…

Synthesis of Polycyclic Indolines by Utilizing a Reduction/Cyclization Cascade Reaction

2021

European journal of organic chemistry 2021(45), 6097-6101 (2021). doi:10.1002/ejoc.202101191

Cover Feature: Synthesis of Polycyclic Indolines by Utilizing a Reduction/Cyclization Cascade Reaction (Eur. J. Org. Chem. 45/2021)

2021

Sodītā empīriskā ticamības funkcija un tās pielietojums vispārinātajam lineārajam modelim

2016

Maģistra darbā aplūkota vispārināto lineāro regresijas modeļu parametru novērtēšana ar soda funkciju un empīriskās ticamības metodēm. Ieviests soda funkcijas jēdziens un aplūkotas vairākas biežāk izmantotās soda funkcijas un to īpašības. Parādīta sodītās mazāko kvadrātu metodes novērtējumu labo īpašību, attiecībā pret nozīmīgo modeļa mainīgo atlasi, izpildīšanās simulētiem datiem. Definēts sodītās ticamības funkcijas jēdziens un aplūkots tās pielietojums vispārināto lineāro modeļu parametru novērtēšanā. Doti nepieciešamie algoritmi metodes praktiskai realizācijai. Sodītā empīriskā ticamības funkcija pielietota daudzdimensiju lineārās un loģistiskās regresijas datiem un secināts, ka metode l…

Condition Assessment and Analysis of Bearing of Doubly Fed Wind Turbines Using Machine Learning Technique

2023

Condition monitoring of wind turbines is progressively increasing to maintain the continuity of clean energy supply to power grids. This issue is of great importance since it prevents wind turbines from failing and overheating, as most wind turbines with doubly fed induction generators (DFIG) are overheated due to faults in generator bearings. Bearing fault detection has become a main topic targeting the optimum operation, unscheduled downtime, and maintenance cost of turbine generators. Wind turbines are equipped with condition monitoring devices. However, effective and reliable fault detection still faces significant difficulties. As the majority of health monitoring techniques are primar…

Intelligent system for electrical heating control based on optical precipitation sensor

2018

Abstract The paper presents testing results of the SCADA system IntelHeat introduced at the Latvian Railways for automated heating control of railway points during winters with the purpose of electricity saving by optimized real-time assignment of heating levels. The system is based on innovative optical sensors of precipitation detecting rain and snow particles using diffuse and specular reflection channels. The results of trial exploitation demonstrated the ability of the IntelHeat system to manage points heating flexibly in accordance with changes of weather conditions and correspondence with archived meteorological data.

Security Wireless Solution for Semantic Smart SCADA/DCS

2015

Journal spécialisé das industrie du gaz; International audience; We present the ability to detect and infiltrate semantic attacks a wireless radio network used in semantic (SCADA/DCS) systems, these attacks deny operators and automated systems the ability to safely and reliably monitor and control semantic sensors, semantic actuators, relays, and breakers. We presented in this work new security semantic wireless protocols as a secure communication support for these modern semantic wireless systems and a global security solution for interconnected (IT-SCADA) platforms.