Estudi de l’eficiència aerodinàmica de vehicles pesants de transport de passatgers

Estudi de l’eficiència aerodinàmica de les carrosseries de vehicles pesants de cara a reduir el consum de combustible en autocars de llarg trajecte. L’estudi es basa en tres aspectes: validació del programa de simulació, estudi aerodinàmic de diferents carrosseries d’autocar de mercat i estudi aerodinàmic de diferents complements

Estudi de la influència del vent en l’estabilitat de vehicles pesants de transport de viatgers.

Investigacions recents revelen com l’acció del vent lateral és un efecte molt important en bona part dels accidents ocorreguts en vehicles pesants de transport per carretera. És per això que el perfil aerodinàmic del vehicle esdevé determinant en l’avaluació de les forces laterals que hi actuen.El present projecte té per objecte determinar les forces laterals que s’exerceixen en vehicles pesants de transport de passatgers degut a l’acció del vent i investigar-ne la seva perillositat. Per fer-ho s’utilitzen models numèrics de dinàmica de fluids i, per diferents velocitats del vehicle, es simulen vents amb diferent intensitat i direcció. D’aquí es determinen unes condicions de perillositat en funció, entre d’altres variables, de l’angle d’incidència del vent i de la seva velocitat

G alpha-q/11 protein plays a key role in insulin-induced glucose transport in 3T3-L1 adipocytes.

We evaluated the role of the G alpha-q (Galphaq) subunit of heterotrimeric G proteins in the insulin signaling pathway leading to GLUT4 translocation. We inhibited endogenous Galphaq function by single cell microinjection of anti-Galphaq/11 antibody or RGS2 protein (a GAP protein for Galphaq), followed by immunostaining to assess GLUT4 translocation in 3T3-L1 adipocytes. Galphaq/11 antibody and RGS2 inhibited insulin-induced GLUT4 translocation by 60 or 75%, respectively, indicating that activated Galphaq is important for insulin-induced glucose transport. We then assessed the effect of overexpressing wild-type Galphaq (WT-Galphaq) or a constitutively active Galphaq mutant (Q209L-Galphaq) by using an adenovirus expression vector. In the basal state, Q209L-Galphaq expression stimulated 2-deoxy-D-glucose uptake and GLUT4 translocation to 70% of the maximal insulin effect. This effect of Q209L-Galphaq was inhibited by wortmannin, suggesting that it is phosphatidylinositol 3-kinase (PI3-kinase) dependent. We further show that Q209L-Galphaq stimulates PI3-kinase activity in p110alpha and p110gamma immunoprecipitates by 3- and 8-fold, respectively, whereas insulin stimulates this activity mostly in p110alpha by 10-fold. Nevertheless, only microinjection of anti-p110alpha (and not p110gamma) antibody inhibited both insulin- and Q209L-Galphaq-induced GLUT4 translocation, suggesting that the metabolic effects induced by Q209L-Galphaq are dependent on the p110alpha subunit of PI3-kinase. In summary, (i) Galphaq appears to play a necessary role in insulin-stimulated glucose transport, (ii) Galphaq action in the insulin signaling pathway is upstream of and dependent upon PI3-kinase, and (iii) Galphaq can transmit signals from the insulin receptor to the p110alpha subunit of PI3-kinase, which leads to GLUT4 translocation.

Iowa's Renewable Energy and Infrastructure Impacts, TR-593, 2010

The federal government is aggressively promoting biofuels as an answer to global climate change and dependence on imported sources of energy. Iowa has quickly become a leader in the bioeconomy and wind energy production, but meeting the United States Department of Energy’s goal having 20% of U.S. transportation fuels come from biologically based sources by 2030 will require a dramatic increase in ethanol and biodiesel production and distribution. At the same time, much of Iowa’s rural transportation infrastructure is near or beyond its original design life. As Iowa’s rural roadway structures, pavements, and unpaved roadways become structurally deficient or functionally obsolete, public sector maintenance and rehabilitation costs rapidly increase. More importantly, costs to move all farm products will rapidly increase if infrastructure components are allowed to fail; longer hauls, slower turnaround times, and smaller loads result. When these results occur on a large scale, Iowa will start to lose its economic competitive edge in the rapidly developing bioeconomy. The primary objective of this study was to document the current physical and fiscal impacts of Iowa’s existing biofuels and wind power industries. A four-county cluster in north-central Iowa and a two-county cluster in southeast Iowa were identified through a local agency survey as having a large number of diverse facilities and were selected for the traffic and physical impact analysis. The research team investigated the large truck traffic patterns on Iowa’s secondary and local roads from 2002 to 2008 and associated those with the pavement condition and county maintenance expenditures. The impacts were quantified to the extent possible and visualized using geographic information system (GIS) tools. In addition, a traffic and fiscal assessment tool was developed to understand the impact of the development of the biofuels on Iowa’s secondary road system. Recommended changes in public policies relating to the local government and to the administration of those policies included standardizing the reporting and format of all county expenditures, conducting regular pavement evaluations on a county’s system, cooperating and communicating with cities (adjacent to a plant site), considering utilization of tax increment financing (TIF) districts as a short-term tool to produce revenues, and considering alternative ways to tax the industry.

Wireless Sensor Networks for Infrastructure Monitoring, TR-611, 2010

A good system of preventive bridge maintenance enhances the ability of engineers to manage and monitor bridge conditions, and take proper action at the right time. Traditionally infrastructure inspection is performed via infrequent periodical visual inspection in the field. Wireless sensor technology provides an alternative cost-effective approach for constant monitoring of infrastructures. Scientific data-acquisition systems make reliable structural measurements, even in inaccessible and harsh environments by using wireless sensors. With advances in sensor technology and availability of low cost integrated circuits, a wireless monitoring sensor network has been considered to be the new generation technology for structural health monitoring. The main goal of this project was to implement a wireless sensor network for monitoring the behavior and integrity of highway bridges. At the core of the system is a low-cost, low power wireless strain sensor node whose hardware design is optimized for structural monitoring applications. The key components of the systems are the control unit, sensors, software and communication capability. The extensive information developed for each of these areas has been used to design the system. The performance and reliability of the proposed wireless monitoring system is validated on a 34 feet span composite beam in slab bridge in Black Hawk County, Iowa. The micro strain data is successfully extracted from output-only response collected by the wireless monitoring system. The energy efficiency of the system was investigated to estimate the battery lifetime of the wireless sensor nodes. This report also documents system design, the method used for data acquisition, and system validation and field testing. Recommendations on further implementation of wireless sensor networks for long term monitoring are provided.

Cation Transport Coupled to ATP Hydrolysis By the (Na, K)-ATPase : an integrated, animated model

An Adobe (R) animation is presented for use in undergraduate Biochemistry courses, illustrating the mechanism of Na+ and K+ translocation coupled to ATP hydrolysis by the (Na, K)-ATPase, a P-2c-type ATPase, or ATP-powered ion pump that actively translocates cations across plasma membranes. The enzyme is also known as an E-1/E-2-ATPase as it undergoes conformational changes between the E-1 and E-2 forms during the pumping cycle, altering the affinity and accessibility of the transmembrane ion-binding sites. The animation is based on Horisberger's scheme that incorporates the most recent significant findings to have improved our understanding of the (Na, K)-ATPase structure function relationship. The movements of the various domains within the (Na, K)-ATPase alpha-subunit illustrate the conformational changes that occur during Na+ and K+ translocation across the membrane and emphasize involvement of the actuator, nucleotide, and phosphorylation domains, that is, the "core engine" of the pump, with respect to ATP binding, cation transport, and ADP and P-i release.

Receptor occupancy vs. induction of Na+-K+-ATPase and Na+ transport by aldosterone.

In the urinary bladder of the toad Bufo marinus aldosterone (between 0.8 and 100 nM) stimulates Na+ transport [half-maximal induction concentration (K1/2) = 6.5 nM]. At low hormone concentrations (0.8-8 nM), the increase of Na+ transport between 0.75 and 2.5 h is accompanied by a fall in transepithelial resistance (R). Higher hormone concentrations (30-800 nM) induce an additional resistance-independent fraction of Na+ transport within 2.5-8 h. From 6 h on, aldosterone (between 0.2 and 20 nM) stimulates in the same tissue the biosynthesis rate of the alpha- and beta-subunits of Na+-K+-ATPase (K1/2 = 3 and 1.5 nM, respectively). New pump synthesis is thus not a prerequisite for the early mineralocorticoid response but might be linked to the late transport event. The mineralocorticoid response is usually ascribed to interaction with the higher affinity type 1 receptor. In the present study we show, however, that at least 55% of the overall Na+ transport response is linked to nuclear occupation of the lower affinity type 2 receptors [dissociation constant (Kd) = 50 nM, maximum number of binding sites (Nmax) = 315 fmol/mg protein]. Distinct aldosterone effects, such as the fall in R and the increase in Na+-K+-ATPase synthesis, are more closely related to occupation of type 1 receptors (Kd = 0.3 nM, Nmax = 23 fmol/mg protein). At maximal induction of these latter parameters, only about 20% of type 2 receptors are occupied. These results suggest that both types of aldosterone receptors are involved in the mediation of the full mineralocorticoid response: type 1 in the early and late and type 2 particularly in the late tissue response.

Harvesting and transport of root biomass from fast-growing poplar plantations

Abstract

Recovery of a persistent Canine distemper virus expressing the enhanced green fluorescent protein from cloned cDNA.

Wild-type A75/17-Canine distemper virus (CDV) is a highly virulent strain, which induces a persistent infection in the central nervous system (CNS) with demyelinating disease. Wild-type A75/17-CDV, which is unable to replicate in cell lines to detectable levels, was adapted to grow in Vero cells and was designated A75/17-V. Sequence comparison between the two genomes revealed seven nucleotide differences located in the phosphoprotein (P), the matrix (M) and the large (L) genes. The P gene is polycistronic and encodes two auxiliary proteins, V and C, besides the P protein. The mutations resulted in amino acid changes in the P and V, but not in the C protein, as well as in the M and L proteins. Here, a rescue system was developed for the A75/17-V strain, which was shown to be attenuated in vivo, but retains a persistent infection phenotype in Vero cells. In order to track the recombinant virus, an additional transcription unit coding for the enhanced green fluorescent protein (eGFP) was inserted at the 3' proximal position in the A75/17-V cDNA clone. Reverse genetics technology will allow us to characterize the genetic determinants of A75/17-V CDV persistent infection in cell culture.

Effects of erythropoietin on muscle O2 transport during exercise in patients with chronic renal failure.

Erythropoietin (rHuEPO) has proven to be effective in the treatment of anemia of chronic renal failure (CRF). Despite improving the quality of life, peak oxygen uptake after rHuEPO therapy is not improved as much as the increase in hemoglobin concentration ([Hb)] would predict. We hypothesized that this discrepancy is due to failure of O2 transport rates to rise in a manner proportional to [Hb]. To test this, eight patients with CRF undergoing regular hemodialysis were studied pre- and post-rHuEPO ([Hb] = 7.5 +/- 1.0 vs. 12.5 +/- 1.0 g x dl-1) using a standard incremental cycle exercise protocol. A group of 12 healthy sedentary subjects of similar age and anthropometric characteristics served as controls. Arterial and femoral venous blood gas data were obtained and coupled with simultaneous measurements of femoral venous blood flow (Qleg) by thermodilution to obtain O2 delivery and oxygen uptake (VO2). Despite a 68% increase in [Hb], peak VO2 increased by only 33%. This could be explained largely by reduced peak leg blood flow, limiting the gain in O2 delivery to 37%. At peak VO2, after rHuEPO, O2 supply limitation of maximal VO2 was found to occur, permitting the calculation of a value for muscle O2 conductance from capillary to mitochondria (DO2). While DO2 was slightly improved after rHuEPO, it was only 67% of that of sedentary control subjects. This kept maximal oxygen extraction at only 70%. Two important conclusions can be reached from this study. First, the increase in [Hb] produced by rHuEPO is accompanied by a significant reduction in peak blood flow to exercising muscle, which limits the gain in oxygen transport. Second, even after restoration of [Hb], O2 conductance from the muscle capillary to the mitochondria remains considerably below normal.

Asset Management Program Enhancement Plan: Baseline Assessment Phases I and II, 2015

This project resulted in the development of a framework for making asset management decisions on low-volume bridges. The research focused on low-volume bridges located in the agricultural counties of Iowa because recent research has shown that these counties have the greatest percentage of structurally deficient bridges in the nation. Many of the same counties also have the highest crop yields in the state, creating a situation where detours caused by deficient bridges on farm-to-market roads increase the cost to transport the crops. Thus, the research proposed the use of social return on investment (SROI), a tool used by international institutions such as the World Bank, as an asset management metric to gauge to the socioeconomic impact of structurally deficient bridges on the state in an effort to provide quantified justification to fund improvements on low-volume assets such as these rural bridges. The study found that combining SROI with current asset management metrics like average daily traffic (ADT) made it possible to prioritize the bridges in such a way that the limited resources available are allocated in a manner that promotes a more equitable distribution and that directly benefits the user, in this case Iowa farmers. The result is a system that more closely aligns itself with the spirit of MAP-21, in that infrastructure investments are used to facilitate economic growth for Iowa’s agricultural economy.

Iowa Infrastructure Investment Program: Report of the Governor on the Status of the I-Jobs Program, January 7, 2011

Department of Management reporting on the status of the Iowa Infrastructure Investment Program, known as the I-JOBS Program, as of September 30, 2010 with additional survey information from departments on the number of positions supported through October 31, 2010.

Annual Infrastructure Status Report 2014

This is the Iowa Department of Transportation’s summary of project status for infrastructure projects that have been appropriated revenue from various funds including Rebuild Iowa Infrastructure, Health Restricted Capitals, Revenue Bonds Capitals and Revenue Bonds Capitals II.

Entropic transport: kinetics, scaling, and control mechanisms

We show that transport in the presence of entropic barriers exhibits peculiar characteristics which makes it distinctly different from that occurring through energy barriers. The constrained dynamics yields a scaling regime for the particle current and the diffusion coefficient in terms of the ratio between the work done to the particles and available thermal energy. This interesting property, genuine to the entropic nature of the barriers, can be utilized to effectively control transport through quasi-one-dimensional structures in which irregularities or tortuosity of the boundaries cause entropic effects. The accuracy of the kinetic description has been corroborated by simulations. Applications to different dynamic situations involving entropic barriers are outlined.