18 research outputs found
Economic crisis and the automotive industry in Romania
The economic crisis has affected many areas but the auto industry is perhaps one of the most affected. Renault, Ford, General Motors, Toyota, Volkswagen, BMW are just some of the big players caught unprepared. Through this paper we propose an analysis of the automotive market in Romania in order to understand the sales decrease of the last two years. At the same time we aimed at understanding the reasons that led to a decrease in car sales, what were the measures taken by the government to stop this phenomenon and how the economic crisis influenced the automotive field in Romania. An objective image of the situation in the automobile market in Romania at this moment also requires an analysis of the marketing environment and the changes it has undergone over time. Last but not least we will try to find a series of measures to re-launch the car market in Romania
On the Origin of Carnivory: Molecular Physiology and Evolution of Plants on an Animal Diet
Synthesis of ZnS thin films from aqueous caustic of trisodium citrate and their properties
Zinc sulfide (ZnS) thin films due to their properties are widely used in various electronic optical devices. They are produced by several methods, among which â vacuum sublimation, high frequency sputtering method, quasiclosed volume method, sol-gel method, electrodeposition. These methods have high energy consumption which increases the price of ZnS thin films. Aim: The aim of this work is to establish the optimal parameters of the synthesis of ZnS thin films of the aqueous caustic and the correlation between content of zinc in the synthesized films determined by the method of stripping voltammetry and thickness, structural, morphological and optical parameters. Materials and Methods: The ZnS thin films were obtained from aqueous caustics of zinc-containing salt using chemical deposition. Fresh solution of zinc-containing salt, trisodium citrate (Na3C6H5O7) as a complexing agent, thiourea ((NH2)2CS) and ammonium hydroxide (NH4OH) was used for the synthesis of ZnS films by chemical deposition. The deposition was performed on prepared glass substrates with the area of 5,76 cm2. Results: The phase mixture of the films has been determined. It showed the presence of ZnS compounds in the cubic modification (sphalerite). Stripping voltammetry was used to determine the mass of zinc in the ZnS films on various conditions of synthesis, namely on the concentration of the initial zinc-containing salt, trisodium citrate, thiourea, deposition time and temperature. The surface morphology, optical properties, the thickness of the ZnS resulting films have been studied. Conclusions: The optimal conditions for the synthesis of ZnS films were found based on these data. Three-dimensional surface morphology of ZnS film studies showed its smoothness, uniformity, integrity and confirmed the correctness of determining the optimal synthesis parameters
Ether anesthetics prevents touch-induced trigger hair calcium-electrical signals excite the Venus flytrap
Plants do not have neurons but operate transmembrane ion channels and can get electrical excited by physical and chemical clues. Among them the Venus flytrap is characterized by its peculiar hapto-electric signaling. When insects collide with trigger hairs emerging the trap inner surface, the mechanical stimulus within the mechanosensory organ is translated into a calcium signal and an action potential (AP). Here we asked how the Ca wave and AP is initiated in the trigger hair and how it is feed into systemic trap calcium-electrical networks. When Dionaea muscipula trigger hairs matures and develop hapto-electric excitability the mechanosensitive anion channel DmMSL10/FLYC1 and voltage dependent SKOR type Shaker K channel are expressed in the sheering stress sensitive podium. The podium of the trigger hair is interface to the flytrapâs prey capture and processing networks. In the excitable state touch stimulation of the trigger hair evokes a rise in the podium Ca2+ first and before the calcium signal together with an action potential travel all over the trap surface. In search for podium ion channels and pumps mediating touch induced Ca transients, we, in mature trigger hairs firing fast Ca signals and APs, found OSCA1.7 and GLR3.6 type Ca channels and ACA2/10 Ca pumps specifically expressed in the podium. Like trigger hair stimulation, glutamate application to the trap directly evoked a propagating Ca and electrical event. Given that anesthetics affect K channels and glutamate receptors in the animal system we exposed flytraps to an ether atmosphere. As result propagation of touch and glutamate induced Ca and AP long-distance signaling got suppressed, while the trap completely recovered excitability when ether was replaced by fresh air. In line with ether targeting a calcium channel addressing a Ca activated anion channel the AP amplitude declined before the electrical signal ceased completely. Ether in the mechanosensory organ did neither prevent the touch induction of a calcium signal nor this post stimulus decay. This finding indicates that ether prevents the touch activated, glr3.6 expressing base of the trigger hair to excite the capture organ
The Venus flytrap trigger hair-specific potassium channel KDM1 can reestablish the K+ gradient required for hapto-electric signaling.
The carnivorous plant Dionaea muscipula harbors multicellular trigger hairs designed to sense mechanical stimuli upon contact with animal prey. At the base of the trigger hair, mechanosensation is transduced into an all-or-nothing action potential (AP) that spreads all over the trap, ultimately leading to trap closure and prey capture. To reveal the molecular basis for the unique functional repertoire of this mechanoresponsive plant structure, we determined the transcriptome of D. muscipula's trigger hair. Among the genes that were found to be highly specific to the trigger hair, the Shaker-type channel KDM1 was electrophysiologically characterized as a hyperpolarization- and acid-activated K+-selective channel, thus allowing the reuptake of K+ ions into the trigger hair's sensory cells during the hyperpolarization phase of the AP. During trap development, the increased electrical excitability of the trigger hair is associated with the transcriptional induction of KDM1. Conversely, when KDM1 is blocked by Cs+ in adult traps, the initiation of APs in response to trigger hair deflection is reduced, and trap closure is suppressed. KDM1 thus plays a dominant role in K+ homeostasis in the context of AP and turgor formation underlying the mechanosensation of trigger hair cells and thus D. muscipula's hapto-electric signaling