Analysis of Voltage Sag in Sub Transmission System

The disturbances created in A C Transmission line power flow due to various faults and unavoidable natural circumstances has to be monitored carefully for uninterrupted power supply to the consumer and to avoid hazardous situations. The subtransmission system with standard 33kv, 66kv, 132kv and 220kv transmission lines which are usually out of sight are considered for analysis purpose. The various faults which occur in transmission lines leading to voltage sag are simulated, modelled and analyzed using MATLAB/SIMULINK tool

Re-equilibration after quenches in athermal martensites:Conversion-delays for vapour to liquid domain-wall phases

Entropy barriers and ageing states appear in martensitic structural-transition models, slowly re-equilibrating after temperature quenches, under Monte Carlo dynamics. Concepts from protein folding and ageing harmonic oscillators turn out to be useful in understanding these nonequilibrium evolutions. We show how the athermal, non-activated delay time for seeded parent-phase austenite to convert to product-phase martensite, arises from an identified entropy barrier in Fourier space. In an ageing state of low Monte Carlo acceptances, the strain structure factor makes constant-energy searches for rare pathways, to enter a Brillouin zone `golf hole' enclosing negative energy states, and to suddenly release entropically trapped stresses. In this context, a stress-dependent effective temperature can be defined, that re-equilibrates to the quenched bath temperature.Comment: 11 pages, 12 figures. Under process with Phys. Rev. B (2015

Animal models of hepatocellular carcinoma prevention

Hepatocellular carcinoma (HCC) is a deadly disease and therapeutic efficacy in advanced HCC is limited. Since progression of chronic liver disease to HCC involves a long latency period of a few decades, a significant window of therapeutic opportunities exists for prevention of HCC and improve patient prognosis. Nonetheless, there has been no clinical advancement in instituting HCC chemopreventive strategies. Some of the major challenges are heterogenous genetic aberrations of HCC, significant modulation of tumor microenvironment and incomplete understanding of HCC tumorigenesis. To this end, animal models of HCC are valuable tools to evaluate biology of tumor initiation and progression with specific insight into molecular and genetic mechanisms involved. In this review, we describe various animal models of HCC that facilitate effective ways to study therapeutic prevention strategies that have translational potential to be evaluated in a clinical context © 2019 by the authors. Licensee MDPI, Basel, Switzerland

Poboljšan postupak sinteze nekih novih 1,3-diaril-2-propen-1-ona koristeći PEG-400 kao reciklirajuće otapalo i njihovo antimikrobno vrednovanje

A simple and convenient route is described for the synthesis of novel hetero 1,3-diaryl-2-propen-1-ones (chalcones) by using recyclable poly PEG-400 as an alternative reaction solvent. The reaction is clean with excellent yield, shorter reaction time and reduces the use of volatile organic compounds (VOCs). All the synthesized compounds were evaluated for their antimicrobial activities against several pathogenic representatives.Opisana je jednostavna i pogodna metoda sinteze novih hetero 1,3-diaril-2-propen-1-ona (kalkona) koristeći poli(etilenglikol) (PEG-400) kao alternativno otapalo. Reakcija je jednoznačna, a uporaba hlapljivih organskih otapala je smanjena. Iskorištenja na produktima su visoka, a reakcijska vremena kraća. Svi sintetizirani spojevi testirani su na antimikrobno djelovanje na nekoliko patogenih mikroorganizama

The brain microenvironment mediates resistance in luminal breast cancer to PI3K inhibition through HER3 activation

Although targeted therapies are often effective systemically, they fail to adequately control brain metastases. In preclinical models of breast cancer that faithfully recapitulate the disparate clinical responses in these microenvironments, we observed that brain metastases evade phosphatidylinositide 3-kinase (PI3K) inhibition despite drug accumulation in the brain lesions. In comparison to extracranial disease, we observed increased HER3 expression and phosphorylation in brain lesions. HER3 blockade overcame the resistance of HER2-amplified and/or PIK3CA-mutant breast cancer brain metastases to PI3K inhibitors, resulting in marked tumor growth delay and improvement in mouse survival. These data provide a mechanistic basis for therapeutic resistance in the brain microenvironment and identify translatable treatment strategies for HER2-amplified and/or PIK3CA-mutant breast cancer brain metastases

The importance of microRNAs in RAS oncogenic activation in human cancer

microRNAs (miRNAs) regulate gene expression by modulating the translation of protein-coding RNAs. Their aberrant expression is involved in various human diseases, including cancer. Here, we summarize the experimental pieces of evidence that proved how dysregulated miRNA expression can lead to RAS (HRAS, KRAS, or NRAS) activation irrespective of their oncogenic mutations. These findings revealed relevant pathogenic mechanisms as well as mechanisms of resistance to target therapies. Based on this knowledge, potential approaches for the control of RAS oncogenic activation can be envisioned

The Binder Index – A Parameter That Influences the Strength of Geopolymer Concrete

Geopolymer concrete (GPC) is an environmentally friendly material in the sense that it uses industrial by-products such as ground granulated blast furnace slag (GGBS) and fly ash (FA), which are activated by an alkaline solution. This paper presents an experimental investigation concerning the strength of the GPC and its relation to a new parameter called the ‘Binder Index (BI)’. The parameters considered in the investigation include GGBS to fly ash ratios (0.25 0.43, 0.67, 1.0, 1.5, and 2.3) and the molarity of the alkaline activator (6, 8, 10, and 12). The binder index combines the effect of the GGBS to the fly ash ratio and the molarity of the alkaline activator. The results have shown that the strength of the GPC is significantly influenced by varying the binder index. The results indicate that a nonlinear relation exists between the binder index and the compressive strength of the GPC and the binder index and the modulus of rupture

Erratum: Understanding Vogel-Fulcher–like equilibration times through the partial equilibration scenario

Original article: EPL, 142 (2023) 3600

Understanding Vogel-Fulcher–like equilibration times through the partial equilibration scenario

We test a post-quench Partial Equilibration Scenario (PES) of Ritort and colleagues, through Monte Carlo quench simulations, of a vector-spin model for a cubic-to-tetragonal, martensitic structural transition. We confirm the PES signature distribution of an exponential tail in heat releases, scaled in an effective search temperature that regulates energy-lowering passages between fixed-energy shells. Our simulations find that this effective temperature vanishes linearly in the deviation of the quench temperature from a divergence temperature, where passage bottlenecks in phase space segment their topology, and entropy barriers diverge. Equilibration delay times, exponential in the inverse effective temperature, are thus predicted to show singular Vogel-Fulcher behaviour, understood here as an arrest of PES heat releases to the bath, and confirmed by experimental data on martensitic alloys