984 resultados para injection vs rapid,


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The role of acid secretion in regulating short-term changes in growth rate and wall extensibility was investigated in emerging first leaves of intact, water-stressed maize (Zea mays L.) seedlings. A novel approach was used to measure leaf responses to injection of water or solutions containing potential regulators of growth. Both leaf elongation and wall extensibility, as measured with a whole-plant creep extensiometer, increased dramatically within minutes of injecting water, 0.5 mm phosphate, or strong (50 mm) buffer solutions with pH ≤ 5.0 into the cell-elongation zone of water-stressed leaves. In contrast, injecting buffer solutions at pH ≥ 5.5 inhibited these fast responses. Solutions containing 0.5 mm orthovanadate or erythrosin B to inhibit wall acidification by plasma membrane H+-ATPases were also inhibitory. Thus, cell wall extensibility and leaf growth in water-stressed plants remained inhibited, despite the increased availability of (injected) water when accompanying increases in acid-induced wall loosening were prevented. However, growth was stimulated when pH 4.5 buffers were included with the vanadate injections. These findings suggest that increasing the availability of water to expanding cells in water-stressed leaves signals rapid increases in outward proton pumping by plasma membrane H+-ATPases. Resultant increases in cell wall extensibility participate in the regulation of water uptake, cell expansion, and leaf growth.

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Head trauma leading to concussion and electroconvulsive shock (ECS) in humans causes amnesia for events that occurred shortly before the injury (retrograde amnesia). The present experiment investigated the amnesic effect of lidocaine and ECS in 25 rats trained on a working memory version of the Morris water task. Each day, the escape platform was moved to a new location; learning was evidenced by a decrease in the latency to find the platform from the first to the second trial. "Consolidation" of this newly encoded spatial engram was disrupted by bilateral inactivation of the dorsal hippocampus with 1 microliter of 4% lidocaine applied as soon as possible after the first trial. When trial 2 was given after recovery from the lidocaine (30 min after the injection), a normal decrease in latency indicated that the new engram was not disrupted. When trial 2 was given under the influence of lidocaine (5 min after injection), absence of latency decrease demonstrated both the success of the inactivation and the importance of hippocampus for the task. To examine the role of events immediately after learning, ECS (30 or 100 mA, 50 Hz, 1.2 sec) was applied 0 sec to 45 sec after a single escape to the new platform location. A 2-h delay between ECS and trial 2 allowed the effects of ECS to dissipate. ECS applied 45 sec or 30 sec after trial 1 caused no retrograde amnesia: escape latencies on trial 2 were the same as in control rats. However, ECS applied 0 sec or 15 sec after trial 1 induced clear retrograde amnesia: escape latencies on trial 2 were no shorter than on trial 1. It is concluded that the consolidation of a newly formed memory for spatial location can only be disrupted by ECS within 30 sec after learning.

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Synaptotagmin (Syt) is an inositol high-polyphosphate series [IHPS inositol 1,3,4,5-tetrakisphosphate (IP4), inositol 1,3,4,5,6-pentakisphosphate, and inositol 1,2,3,4,5,6-hexakisphosphate] binding synaptic vesicle protein. A polyclonal antibody against the C2B domain (anti-Syt-C2B), an IHPS binding site, was produced. The specificity of this antibody to the C2B domain was determined by comparing its ability to inhibit IP4 binding to the C2B domain with that to inhibit the Ca2+/phospholipid binding to the C2A domain. Injection of the anti-Syt-C2B IgG into the squid giant presynapse did not block synaptic release. Coinjection of IP4 and anti-Syt-C2B IgG failed to block transmitter release, while IP4 itself was a powerful synpatic release blocker. Repetitive stimulation to presynaptic fiber injected with anti-Syt-C2B IgG demonstrated a rapid decline of the postsynaptic response amplitude probably due to its block of synaptic vesicle recycling. Electron microscopy of the anti-Syt-C2B-injected presynapse showed a 90% reduction of the numbers of synaptic vesicles. These results, taken together, indicate that the Syt molecule is central, in synaptic vesicle fusion by Ca2+ and its regulation by IHPS, as well as in the recycling of synaptic vesicles.

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Studies on cultured cells have shown that agonists induce several types of G protein-coupled receptors to undergo internalization. We have investigated this phenomenon in rat striatum, using substance P (SP)-induced internalization of the SP receptor (SPR) as our model system. Within 1 min of a unilateral striatal injection of SP in the anesthetized rat, nearly 60% of the SPR-immunoreactive neurons within the injection zone display massive internalization of the SPR--i.e., 20-200 SPR+ endosomes per cell body. Within the dendrites the SPR undergoes a striking translocation from the plasma membrane to endosomes, and these dendrites also undergo a morphological reorganization, changing from a structure of rather uniform diameter to one characterized by large, swollen varicosities connected by thin fibers. In both cell bodies and dendrites the number of SPR+ endosomes returns to baseline within 60 min of SP injection. The number of neurons displaying substantial endosomal SPR internalization is dependent on the concentration of injected SP, and the SP-induced SPR internalization is inhibited by the nonpeptide neurokinin 1 receptor antagonist RP-67,580. These data demonstrate that in the central nervous system in vivo, SP induces a rapid and widespread SPR internalization in the cell bodies and dendrites and a structural reorganization of the dendrites. These results suggest that many of the observations that have been made on the internalization and recycling of G protein-coupled receptors in in vitro transfected cell systems are applicable to similar events that occur in the mammalian central nervous system in vivo.

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The mountain ranges and coastlines of Washington State have steep slopes, and they are susceptible to landslides triggered by intense rainstorms, rapid snow melts, earthquakes, and rivers and waves removing slope stability. Over a 30-year timespan (1984-2014 and includes State Route (SR) 530), a total of 28 deep-seated landslides caused 300 million dollars of damage and 45 deaths (DGER, 2015). During that same timeframe, ten storm events triggered shallow landslides and debris flows across the state, resulting in nine deaths (DGER, 2015). The loss of 43 people, due to the SR 530 complex reactivating and moving at a rate and distance unexpected to residents, highlighted the need for an inventory of the stateís landslides. With only 13% of the state mapped (Lombardo et al., 2015), the intention of this statewide inventory is to communicate hazards to citizens and decision makers. In order to compile an accurate and consistent landslide inventory, Washington needs to adopt a graphic information system (GIS) based mapping protocol. A mapping protocol provides consistency for measuring and recording information about landslides, including such information as the type of landslide, the material involved, and the size of the movement. The state of Oregon shares similar landslide problems as Washington, and it created a GIS-based mapping protocol designed to inform its residents, while also saving money and reducing costly hours in the field (Burns and Madin, 2009). In order to determine if the Oregon Department of Geology and Mineral Industries (DOGAMI) protocol, developed by Burns and Madin (2009), could serve as the basis for establishing Washingtonís protocol, I used the office-based DOGAMI protocol to map landslides along a 40-50 km (25-30 mile) shoreline in Thurston County, Washington. I then compared my results to the field-based landslide inventory created in 2009 by the Washington Division of Geology and Earth Resources (DGER) along this same shoreline. If the landslide area I mapped reasonably equaled the area of the DGER (2009) inventory, I would consider the DOGAMI protocol useful for Washington, too. Utilizing 1m resolution lidar flown for Thurston County in 2011 and a GIS platform, I mapped 36 landslide deposits and scarp flanks, covering a total area of 879,530 m2 (9,467,160 ft2). I also found 48 recent events within these deposits. With an exception of two slides, all of the movements occurred within the last fifty years. Along this same coastline, the DGER (2009) recorded 159 individual landslides and complexes, for a total area of 3,256,570 m2 (35,053,400 ft2). At a first glance it appears the DGER (2009) effort found a larger total number and total area of landslides. However, in addition to their field inventory, they digitized landslides previously mapped by other researchers, and they did not field confirm these landslides, which cover a total area of 2,093,860 m2 (22,538,150 ft2) (DGER, 2009). With this questionable landslide area removed and the toes and underwater landslides accounted for because I did not have a bathymetry dataset, my results are within 6,580 m2 (70,840 ft2) of the DGERís results. This similarity shows that the DOGAMI protocol provides a consistent and accurate approach to creating a landslide inventory. With a few additional modifications, I recommend that Washington State adopts the DOGAMI protocol. Acquiring additional 1m lidar and adopting a modified DOGAMI protocol poises the DGER to map the remaining 87% of the state, with an ultimate goal of informing citizens and decision makers of the locations and frequencies of landslide hazards on a user-friendly GIS platform.

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The synthesis, structural characterization, and photophysical behavior of a 14-membered tetraazamacrocycle with pendant 4-dimethylaminobenzyl (DMAB) and 9-anthracenylmethyl groups is reported (L-3, 6-((9-anthracenylmethyl)amino)-trans-6,13-dimethyl-13-((4-dimethylaminobenzyl)amino)-1,4,8,11-tetraaza-cyclotetradecane). In its free base form, this compound displays rapid intramolecular photoinduced electron transfer (PET) quenching of the anthracene emission, with both the secondary amines and the DMAB group capable of acting as electron donors. When complexed with Zn(II), the characteristic fluorescence of the anthracene chromophore is restored as the former of these pathways is deactivated by coordination. Importantly, it is shown that the DMAB group, which remains uncoordinated and PET active, acts only very weakly to quench emission, by comparison to the behavior of a model Zn complex lacking the pendant DMAB group, [ZnL2](2+) (Chart 1). By contrast, Stern-Volmer analysis of intermolecular quenching of [ZnL2](2+) by N,N-dimethylaniline (DMA) has shown that this reaction is diffusion limited. Hence, the pivotal role of the bridge in influencing intramolecular PET is highlighted.

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Objective: Five double-blind, randomized, saline-controlled trials (RCTs) were included in the United States marketing application for an intra-articular hyaluronan (IA-HA) product for the treatment of osteoarthritis (OA) of the knee. We report an integrated analysis of the primary Case Report Form (CRF) data from these trials. Method. Trials were similar in design, patient population and outcome measures - all included the Lequesne Algofunctional Index (LI), a validated composite index of pain and function, evaluating treatment over 3 months. Individual patient data were pooled; a repeated measures analysis of covariance was performed in the intent-to-treat (ITT) population. Analyses utilized both fixed and random effects models. Safety data from the five RCTs were summarized. Results: A total of 1155 patients with radiologically confirmed knee OA were enrolled: 619 received three or five IA-HA injections; 536 received. placebo saline injections. In the active and control groups, mean ages were 61.8 and 61.4 years; 62.4% and 58.8% were women; baseline total Lequesne scores 11.03 and 11.30, respectively. Integrated analysis of the pooled data set found a statistically significant reduction (P < 0.001) in total Lequesne score with hyaluronan (HA) (-2.68) vs placebo (-2.00); estimated difference -0.68 (95% CI: -0.56 to -0.79), effect size 0.20. Additional modeling approaches confirmed robustness of the analyses. Conclusions: This integrated analysis demonstrates that multiple design factors influence the results of RCTs assessing efficacy of intra-articular (IA) therapies, and that integrated analyses based on primary data differ from meta-analyses using transformed data. (C) 2006 OsteoArthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

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Aim of study: As part of a Cochrane review of viscosupplementation in knee OA, randomised controlled trials (RCT) were reviewed to evaluate evidence for the efficacy of viscosupplementation with Hylan G-F 20 compared to placebo. Methods: Electronic searches were conducted of MEDLINE, EMBASE, Premedline, Current Contents, and CENTRAL. Human, RCT involving Hylan G-F 20 compared to placebo, published prior to 1Q2004, were included. Trials were selected and data extracted by two independent reviewers. Methodological quality was assessed with the Jadad criteria by two reviewers. Data on the OARSI and OMERACT core set clinical outcome measures were extracted where possible. Weighted mean difference (WMD), based on post-test scores, and 95% confidence intervals (CI) were calculated for continuous outcome measures and relative risk (RR) for dichotomous outcome measures. Results: Seven RCT met the inclusion criteria. Median methodological quality was 4 (range 1–5). A further two studies were only reported in abstract form (Jadad score Z 1) and contained insufficient extractable data for inclusion in the analysis. Nine RCT, which compared Hylan G-F 20 to other interventions such as intra-articular corticosteroid, physiotherapy, NSAID, appropriate care, intra-articular gaseous oxygen and other hyaluronan, are not reported here. Twenty-three studies failed to meet inclusion criteria and were excluded. Hylan G-F 20 was more efficacious than placebo at 1–4 weeks post-injection for pain on weight-bearing WMD (random effects [RE]) 13 mm on a 0–100 mm VAS (P Z 0.002) based on 6 RCT. This difference was even greater at 5–13 weeks post-injection, 22 m (RE) (P Z 0.001) based on 5 RCT, and at 14–6 weeks postinjection, 21 m (RE) (P Z 0.006) based on 4 RCT. Hylan G-F 20 was more efficacious than placebo at 1–4 weeks post-injection for pain at night, WMD 7 mm on a 0–100 mm VAS (P Z 0.003) based on 5 RCT. This difference was even greater at 5–13 weeks post-injection, 11 mm (P Z 0.008) based on 4 RCT, and at 14–26 weeks post-injection, 17 mm (P ! 0.00001) based on 3 RCT. There was no significant difference (WMD 8 mm) between Hylan G-F 20 C oral placebo and arthrocentesis C oral placebo at 5–13 weeks post-injection for WOMAC Pain, but Hylan G-F 20 C oral placebo was more efficacious than arthrocentesis C oral placebo for WOMAC Function, WMD 9 mm on a 0–100 mm VAS (P Z 0.01) (Dickson, 2001). Hylan G-F 20 was more effective than placebo at 1–4 weeks postinjection for the variable designed treatment efficacy, WMD 22 mm on a 0–100 mm VAS (P ! 0.00001) based on improvement in 4 RCT. This difference was even greater at 5–13 weeks post injection, 35 mm (P ! 0.00001). Conclusions: Evidence from this updated Cochrane review supports the superior efficacy of Hylan G-F 20 compared to placebo on weight-bearing pain, night pain, function and treatment efficacy in the treatment of knee OA.

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The mechanism behind the immunostimulatory effect of the cationic liposomal vaccine adjuvant dimethyldioctadecylammonium and trehalose 6,6′- dibehenate (DDA:TDB) has been linked to the ability of these cationic vesicles to promote a depot after administration, with the liposomal adjuvant and the antigen both being retained at the injection site. This can be attributed to their cationic nature, since reduction in vesicle size does not influence their distribution profile yet neutral or anionic liposomes have more rapid clearance rates. Therefore the aim of this study was to investigate the impact of a combination of reduced vesicle size and surface pegylation on the biodistribution and adjuvanticity of the formulations, in a bid to further manipulate the pharmacokinetic profiles of these adjuvants. From the biodistribution studies, it was found that with small unilamellar vesicles (SUVs), 10% PEGylation of the formulation could influence liposome retention at the injection site after 4 days, whilst higher levels (25 mol%) of PEG blocked the formation of a depot and promote clearance to the draining lymph nodes. Interestingly, whilst the use of 10% PEG in the small unilamellar vesicles did not block the formation of a depot at the site of injection, it did result in earlier antibody response rates and switch the type of T cell responses from a Th1 to a Th2 bias suggesting that the presence of PEG in the formulation not only control the biodistribution of the vaccine, but also results in different types of interactions with innate immune cells. © 2012 Elsevier B.V.

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Rotational moulding is a unique manufacturing technique for the production of hollow plastic parts manufacturing. Moulds for rotational moulding are generally not standardized, such as for injection moulding, so each new mould must be completely manufactured except for a few ancillary parts like screws or clamps. The aim of this work has been to adapt and apply the advantages of rapid prototyping and electroforming technologies to try to achieve an innovative mould design for rotational moulding. The new innovative design integrates an electroformed shell, manufactured starting from a rapid prototyping mandrel, with different designed standard aluminium tools. The shell holder enables mould assembly with high precision a shell in a few minutes with the advantage of changing different geometries of the electroformed shells in the same tool. The overall mould cost is significantly decreased because it is only necessary to manufacture one or two shells each time, however the rest of the elements of the mould are standard and usable for an infinite number of shells, depending on size. The rapid prototyping of the mandrel enables a significant decrease the global cost of mould manufacturing as well. © 2008 Taylor & Francis Group.

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The teleost fish nonapeptides, arginine vasotocin (AVT) and isotocin (IT), have been implicated in the regulation of social behavior. These peptides are expected to be involved in acute and transient changes in social context, in order to be efficient in modulating the expression of social behavior according to changes in the social environment. Here we tested the hypothesis that short-term social interactions are related to changes in the level of both nonapeptides across different brain regions. For this purpose we exposed male zebrafish to two types of social interactions: (1) real opponent interactions, from which a Winner and a Loser emerged; and (2) mirror-elicited interactions, that produced individuals that did not experience a change in social status despite expressing similar levels of aggressive behavior to those of participants in real-opponent fights. Non-interacting individuals were used as a reference group. Each social phenotype (i.e. Winners, Losers, Mirror-fighters) presented a specific brain profile of nonapeptides when compared to the reference group. Moreover, the comparison between the different social phenotypes allowed to address the specific aspects of the interaction (e.g. assessment of opponent aggressive behavior vs. self-assessment of expressed aggressive behavior) that are linked with neuropeptide responses. Overall, agonistic interactions seem to be more associated with the changes in brain AVT than IT, which highlights the preferential role of AVT in the regulation of aggressive behavior already described for other species.

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A simple and rapid flow-injection spectrophotometric method is reported for the determination of dipyrone in pharmaceutical formulations. The method is based on the reaction of dipyrone with ammonium molybdate in acidic medium to produce blue molybdenum, which was detected spectrophotometrically at 620 nm. The analyte was determined in a single-line flow system. The calibration curve obtained was linear in the range of 5x10(-4) to 8x10(-3) mol L-1 for dipyrone concentration and the precision ( s r =1.7%) was satisfactory. The method proved to be selective and adequately sensitive. Application of the method to the analysis of pharmaceutical samples resulted in excellent accuracy; the percent mean recoveries were in the range 95.3%-101% and relative errors less than 5.0% for five pharmaceutical formulations were found.

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This manuscript reports the overall development of a Ph.D. research project during the “Mechanics and advanced engineering sciences” course at the Department of Industrial Engineering of the University of Bologna. The project is focused on the development of a combustion control system for an innovative Spark Ignited engine layout. In details, the controller is oriented to manage a prototypal engine equipped with a Port Water Injection system. The water injection technology allows an increment of combustion efficiency due to the knock mitigation effect that permits to keep the combustion phasing closer to the optimal position with respect to the traditional layout. At the beginning of the project, the effects and the possible benefits achievable by water injection have been investigated by a focused experimental campaign. Then the data obtained by combustion analysis have been processed to design a control-oriented combustion model. The model identifies the correlation between Spark Advance, combustion phasing and injected water mass, and two different strategies are presented, both based on an analytic and semi-empirical approach and therefore compatible with a real-time application. The model has been implemented in a combustion controller that manages water injection to reach the best achievable combustion efficiency while keeping knock levels under a pre-established threshold. Three different versions of the algorithm are described in detail. This controller has been designed and pre-calibrated in a software-in-the-loop environment and later an experimental validation has been performed with a rapid control prototyping approach to highlight the performance of the system on real set-up. To further make the strategy implementable on an onboard application, an estimation algorithm of combustion phasing, necessary for the controller, has been developed during the last phase of the PhD Course, based on accelerometric signals.

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The thesis work deals with topics that led to the development of innovative control-oriented models and control algorithms for modern gasoline engines. Knock in boosted spark ignition engines is the widest topic discussed in this document because it remains one of the most limiting factors for maximizing combustion efficiency in this kind of engine. First chapter is thus focused on knock and a wide literature review is proposed to summarize the preliminary knowledge that even represents the background and the reference for discussed activities. Most relevant results achieved during PhD course in the field of knock modelling and control are then presented, describing every control-oriented model that led to the development of an adaptive model-based combustion control system. The complete controller has been developed in the context of the collaboration with Ferrari GT and it allowed to completely redefine the knock intensity evaluation as well as the combustion phase control. The second chapter is focused on the activity related to a prototyping Port Water Injection system that has been developed and tested on a turbocharged spark ignition engine, within the collaboration with Magneti Marelli. Such system and the effects of injected water on the combustion process were then modeled in a 1-D simulation environment (GT Power). Third chapter shows the development and validation of a control-oriented model for the real-time calculation of exhaust gas temperature that represents another important limitation to the performance increase in modern boosted engines. Indeed, modelling of exhaust gas temperature and thermocouple behavior are themes that play a key role in the optimization of combustion and catalyst efficiency.

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I materiali compositi possiedono proprietà funzionali e di resistenza sempre più performanti grazie alla natura dei rinforzanti in fibra di carbonio, i quali però sono caratterizzati da criticità relative al processo di trasformazione altamente energivoro e dispendioso, all’inquinamento collegato alla produzione delle fibre e al trattamento di sizing, nonché alla difficoltà nello stadio di separazione dei costituenti del manufatto composito e del conseguente riciclo. A causa di queste problematiche sono stati introdotti in produzione materiali a matrice epossidica rinforzata con fibre di lino. Lo studio è stato indirizzato verso la caratterizzazione delle materie prime che compongono i manufatti, quindi fibre e semilavorati, mediante analisi termiche dinamiche in DSC e TGA con il fine di determinare la composizione e resistenza dei singoli componenti e la misura della variazione nel comportamento quando sono uniti per comporre i prepreg. Sono state eseguite delle prove di igroscopicità, umidità e densità per ottenere una panoramica precisa sulle differenze nella struttura delle fibre in carbonio e lino che le differenzia in modo apprezzabile. Sono stati laminati compositi reticolati secondo tecnologia in autoclave, le cui proprietà sono state definite mediante prove termiche dinamiche in DSC, TGA, DMA, prove alla fiamma mediante conocalorimetro, prove fisiche di igroscopicità, umidità e densità, prove ottiche al SEM in seguito ad una rottura in trazione. Parte del progetto seguito è stato direzionato all’ottimizzazione del ciclo produttivo in autoclave. La simulazione del nuovo ciclo di cura industriale, RAPID, è stata eseguita per valutare la variazione della Tg finale e il grado di curing, nonché le proprietà termiche e meccaniche già valutate nel ciclo di cura, STANDARD.