Search results for " stability."

Activation of NF-kappaB and IL-8 by yersinia enterocolitica invasin protein is conferred by engagement of rac1 and MAP kinase cascades.

2003

International audience; Yersinia enterocolitica triggers activation of the nuclear factor (NF)-kappaB and production of the proinflammatory chemokine interleukin (IL)-8 in intestinal epithelial cells. This activation is due to adhesion of the bacteria via their outer membrane protein invasin to the host cells. Using Clostridium difficile toxins that specifically inactivate small GTPases, and transfection of inhibitory proteins of the Rho-GTPases, we demonstrate that Rac1, but not Cdc42 or Rho, is required for activation of NF-kappaB by invasin. Invasin activated the mitogen activated protein kinases (MAPK) p38 and c-Jun N-terminal protein kinase (JNK) but not extracellular signal regulated …

On the scientific work of Victor Isakov

2022

The preservation of the Agrigento Cathedral

2013

The Agrigento Cathedral was built about nine centuries ago on the edge of a steep slope made up of alternating inclined layers of soft calcarenites and fine-grained soils; its behaviour has never been satisfactory especially as far as the North aisle is concerned. Many corrective measures have been attempted during its lifespan and also a few years ago. They proved invariably unsuccessful. Recent geotechnical investigations, referred to in the paper, permitted to find out that the main cause of the Cathedral distress is a sliding mechanism involving the upper zone of the slope underlying the North aisle; consequently the essential requirement for the preservation of the Cathedral is the sta…

Impact of non-programmable distributed generation in an islanded microgrid: the case study of Ustica

2022

The paper presents a systematic analysis of nonprogrammable distributed generation impact in an islanded microgrid Different issues have been analyzed, with a special focus on the most significant ones in a small islanded network. To this aim, the case study of Ustica island was considered A digital twin of the MV network was developed starting from the network topology data and the power measurement acquired in each secondary substation. Simulations were then performed in the hypothesis of a large increment of distributed generation installation into the network. A discussion is then reported on which are the main technical issues to be faced in the considered case study.

The Institutions of Authoritarian Neoliberalism in Malaysia: A Critical Review of the Development Agendas Under the Regimes of Mahathir, Abdullah, an…

2018

After toppling the 61-year dominant Barisan Nasional through a historic election victory in May 2018, expectations are high for the new ruling government led by Mahathir Mohamad and the Pakatan Harapan to fulfil their promises for socio-economic reforms and regime change in Malaysia. But what have been the institutions of the prevailing regime that need to be reformed and changed? This article offers a critical review of the evolving development agendas since the 1990s of the successive governments of Mahathir Mohamad, Abdullah Badawi, and Najib Razak, each couched in different catchphrases: Wawasan 2020, Islam Hadhari, and 1Malaysia. A close reading of these programs suggests that their su…

On the Stability of the Soft Pendulum With Affine Curvature: Open-Loop, Collocated Closed-Loop, and Switching Control

2022

This letter investigates the stability properties of the soft inverted pendulum with affine curvature - a template model for nonlinear control of underactuated soft robots. We look at how changes in physical parameters affect stability and equilibrium. We give conditions under which zero dynamics corresponding to a collocated choice of the output is (locally or globally) stable or unstable. We leverage these results to design a switching controller that stabilizes a class of nonlinear equilibria of the pendulum, which can drive the system from one equilibrium to another.

Sonication-Induced Modification of Carbon Nanotubes: Effect on the Rheological and Thermo-Oxidative Behaviour of Polymer-Based Nanocomposites.

2018

The aim of this work is the investigation of the effect of ultrasound treatment on the structural characteristics of carbon nanotubes (CNTs) and the consequent influence that the shortening induced by sonication exerts on the morphology, rheological behaviour and thermo-oxidative resistance of ultra-high molecular weight polyethylene (UHMWPE)-based nanocomposites. First, CNTs have been subjected to sonication for different time intervals and the performed spectroscopic and morphological analyses reveal that a dramatic decrease of the CNT's original length occurs with increased sonication time. The reduction of the initial length of CNTs strongly affects the nanocomposite rheological behavio…

Development of microfluidics for sorting of carbon nanotubes

2018

Sorting of carbon nanotubes by their chirality is the current bottleneck in the way to their broad employment based on their exceptional electronic and optical properties. Despite the extensive effort, there is no known method, which would result in really pure chirality ensembles. Previously reported sorting protocols result in enrichment rather than in sorting, alter electronic structure, and suffer from low yield. This is mostly due to the statistical approach, where the nanotubes with mixed chiralities are treated as a set. In this thesis, we propose a new sorting technique based on nanotube-by-nanotube compartmelization, characterization, and sorting in a continuously running droplet-b…

Application of the PHREEQC Program to Assess the Chemical Stability of Tap Water in Kielce

2020

Badania przeprowadzono na próbkach wody w Kielcach pochodzące z dwóch ujęć: Białogon i Zagnańsk. Przedstawiono wyniki wybranych wskaźników dla tych wód, m.in. najważniejszych wpływających na ich stabilność chemiczną, tj. wapnia lub magnezu. Następnie, za pomocą programu PHREEQC, obliczono wskaźniki stabilności dla wód w Kielcach z dwóch ujęć, o których mowa. W kolejnym etapie sprawdzono poprawność metody badania wody za pomocą programu poprzez bilans jonowy wody i porównanie pH wyznaczonej wody z wartością wyznaczoną w wyniku obliczeń. Dla wyżej wymienionych czynności przygotowano tabele i obliczenia, na podstawie których wyciągnięto odpowiednie wnioski

Kognitīvo uzdevumu ietekme uz stājas stabilitāti jauniem un veciem cilvēkiem

2017

Kopsavilkums Palielinoties cilvēka vecumam, palielinās kritienu un traumatisma riski. Tā kā Latvijā, kā arī Eiropā kopumā, palielinās populācijas novecošanās, kritienu un traumatisma riski pieaug, un to samazināšanai ir nepieciešami efektīvi profilaktiski pasākumi, kas uzlabotu īpaši gados veco cilvēku mobilitāti un novērstu kritienus. Pašreiz nav vienotu vadlīniju stājas stabilitātes pārbaužu metodikā un uzlabošanā, tādēļ ir nozīmīgi izprast faktorus, kas var ietekmēt posturālo kontroli. Tādejādi darbā tika izvirzīts mērķis noskaidrot kognitīvo procesu ietekmi uz stājas stabilitāti, kā arī izvērtēt antropometrisko parametru ietekmi uz līdzsvara saglabāšanu. Pētījumā piedalījās 60 izmeklēja…