Asphalt cement concrete pavement recycling, Cass and Montgomery Counties : final report for Iowa DOT project HR-1018, Federal Highway Administration demonstration project no. 39, contract no. DOT-FH-15-336, 1986

This demonstration project consisted of three adjacent highway resurfacing projects using asphalt cement concrete removed from an Interstate highway which had become severely rutted.

Iowa DOT Project Management Peer Exchange, 2016

This project supported the planning and conduct of a two-day Iowa Department of Transportation–hosted peer exchange for state agencies that have implemented some or all of the suggested strategies outlined in the Second Strategic Highway Research Program–sponsored project R10, Project Management Strategies for Complex Projects. Presentations were made by participating states, and several opportunities were provided for directed discussion. General themes emerging from the presentations and discussions were identified as follows: To implement improvements in project management processes, agency leadership needs to decide that a new approach to project management is worth pursuing and then dedicate resources to developing a project management plan. The change to formalized project management and five-dimensional project management (5DPM) requires a culture shift in agencies from segmented “silo” processes to collaborative, cooperative processes that make communication and collaboration high priorities. Agencies need trained project managers who are empowered to execute the project management plan, as well as properly trained functional staff. Project management can be centralized or decentralized with equal effect. After an agency’s project management plan and structure are developed, software tools and other resources should be implemented to support the plan and structure. All projects will benefit from enhanced project management, but the project management plan should specify appropriate approaches for several project levels as defined by factors in addition to dollar value. Project management should be included in an agency’s project development manual.

Draft Project Management Update to the Iowa DOT Project Development Manual, 2016

This work supported drafting project management guidance for the Iowa Department of Transportation (DOT). The goal is to incorporate a greater focus on project management in their project development process. A technical advisory committee (TAC) was assembled to accomplish this effort. The TAC took into consideration the current status of project management with the Iowa DOT, their experience during the demonstration workshop held in Iowa as part of the implementation assistance they received, the project management peer exchange hosted by the Iowa DOT, and additional examples of project management that were presented. With this basis, the TAC participated in a number of discussions to develop draft guidance for the foundation of a Project Management Office (PMO) within the Iowa DOT. The final report describes the process that was used in establishing this guidance. The report details the decisions and decision process that the TAC employed in this endeavor and provides additional thoughts and insight into the draft guidance. Appendix A includes the draft guidance in the form of PMO function details and detailed lists of project management roles and responsibilities. Appendix B includes a starter list of project management resources for the PMO.

Self-Assembled InAs/GaAs Quantum Dot Solar Cells

Our work focuses on experimental and theoretical studies aimed at establishing a fundamental understanding of the principal electrical and optical processes governing the operation of quantum dot solar cells (QDSC) and their feasibility for the realization of intermediate band solar cell (IBSC). Uniform performance QD solar cells with high conversion efficiency have been fabricated using carefully calibrated process recipes as the basis of all reliable experimental characterization. The origin for the enhancement of the short circuit current density (Jsc) in QD solar cells was carefully investigated. External quantum efficiency (EQE) measurements were performed as a measure of the below bandgap distribution of transition states. In this work, we found that the incorporation of self-assembled quantum dots (QDs) interrupts the lattice periodicity and introduce a greatly broadened tailing density of states extending from the bandedge towards mid-gap. A below-bandgap density of states (DOS) model with an extended Urbach tail has been developed. In particular, the below-bandgap photocurrent generation has been attributed to transitions via confined energy states and background continuum tailing states. Photoluminescence measurement is used to measure the energy level of the lowest available state and the coupling effect between QD states and background tailing states because it results from a non-equilibrium process. A basic I-V measurement reveals a degradation of the open circuit voltage (Voc) of QD solar cells, which is related to a one sub-bandgap photon absorption process followed by a direct collection of the generated carriers by the external circuit. We have proposed a modified Shockley-Queisser (SQ) model that predicts the degradation of Voc compared with a reference bulk device. Whenever an energy state within the forbidden gap can facilitate additional absorption, it can facilitate recombination as well. If the recombination is non-radiative, it is detrimental to solar cell performance. We have also investigated the QD trapping effects as deep level energy states. Without an efficient carrier extraction pathway, the QDs can indeed function as mobile carriers traps. Since hole energy levels are mostly connected with hole collection under room temperature, the trapping effect is more severe for electrons. We have tried to electron-dope the QDs to exert a repulsive Coulomb force to help improve the carrier collection efficiency. We have experimentally observed a 30% improvement of Jsc for 4e/dot devices compared with 0e/dot devices. Electron-doping helps with better carrier collection efficiency, however, we have also measured a smaller transition probability from valance band to QD states as a direct manifestation of the Pauli Exclusion Principle. The non-linear performance is of particular interest. With the availability of laser with on-resonance and off-resonance excitation energy, we have explored the photocurrent enhancement by a sequential two-photon absorption (2PA) process via the intermediate states. For the first time, we are able to distinguish the nonlinearity effect by 1PA and 2PA process. The observed 2PA current under off-resonant and on-resonant excitation comes from a two-step transition via the tailing states instead of the QD states. However, given the existence of an extended Urbach tail and the small number of photons available for the intermediate states to conduction band transition, the experimental results suggest that with the current material system, the intensity requirement for an observable enhancement of photocurrent via a 2PA process is much higher than what is available from concentrated sun light. In order to realize the IBSC model, a matching transition strength needs to be achieved between valance band to QD states and QD states to conduction band. However, we have experimentally shown that only a negligible amount of signal can be observed at cryogenic temperature via the transition from QD states to conduction band under a broadband IR source excitation. Based on the understanding we have achieved, we found that the existence of the extended tailing density of states together with the large mismatch of the transition strength from VB to QD and from QD to CB, has systematically put into question the feasibility of the IBSC model with QDs.

Selected Reaction Monitoring (SRM) frente a Western Blot

We propose the SRM technology as a complementary method to the Western Blot for the detection and quantification of proteins in a sample. The technique Western Blot has its own limitations: i) only a protein-of-choice is detected, ignoring any non-relevant proteins, ii) the sensitivity of the technique depends on the specificity of the antibody and iii) Western Blot is expensive and time-consuming. The advantages of SRM with respect Western Blot are remarkable: i) you can detect up to hundreds of different proteins in a sample, ii) SRM is more sensitive, because just 50 copies of the target protein per cell are enough for the detection and iii) once it has been made an investment in the necessary machinery to develop this technique, the detection of proteins in a sample turns into a cheaper, faster, more specific and full-quantitative procedure, without the need of using antibodies. First of all, SRM requires the identification of little peptides, obtained by tryptic digestion, whose sequence must be unique for a single protein or isoform. There is software for that aim. Then, it’s necessary to create isotope-labeled peptides of that identified for acting as internal standards. That sample is introduced in a triple quadrupole mass spectrometer: it passes through a first quadrupole, which functions as a filter, where the fragments are selected, previously ionized, attending to the mass/charge (m/z) relation that correspond to that unique fragments of the protein of interest. In this first selection may be other peptides from other proteins, with the same m/z but with different sequence. To select those that are exclusive from the target protein, the fragments are moved to a second quadrupole, where they are fragmented again with a physical method, and so new smaller fragments are generated. All the new fragments are conduced to the third quadrupole, where just those which come from the protein of interest are selected, attending at their m/z again. The target peptide concentration is determined by measuring the observed signal response for the target peptide relative to that of the isotopic-labeled peptide, the concentration of which is calculated from a pre-determined calibration-response curve. Calibration curves have to be generated for each target peptide in the sample. Because SRM technology is increasing its use, there have been developed databases where the scientific community upload information about protocols and standards for each protein with the aim to facilitate the work to other researchers.

Síntese e caracterização de nanocompósitos de carbon-dot e lantanídeos

Dissertação (mestrado)—Universidade de Brasília, Instituto de Química, 2015.

Role of the wetting layer in the enhanced responsivity of InAs/GaAsSb quantum dot infrared photodetectors

InAs/GaAs1−xSbx Quantum Dot (QD) infrared photodetectors are analyzed by photocurrent spectroscopy. We observe that the integrated responsivity of the devices is improved with the increasing Sb mole fraction in the capping layer, up to 4.2 times for x = 17%. Since the QD layers are not vertically aligned, the vertical transport of the carriers photogenerated within the QDs takes place mainly through the bulk material and the wetting layer of the additional QD regions. The lower thickness of the wetting layer for high Sb contents results in a reduced capture probability of the photocarriers, thus increasing the photoconductive gain and hence, the responsivity of the device. The growth of not vertically aligned consecutive QD layers with a thinner wetting layer opens a possibility to improve the performance of quantum dot infrared photodetectors.

Slow passage through thresholds in quantum dot lasers

A turn on of a quantum dot (QD) semiconductor laser simultaneously operating at the ground state (GS) and excited state (ES) is investigated both experimentally and theoretically. We find experimentally that the slow passage through the two successive laser thresholds may lead to significant delays in the GS and ES turn ons. The difference between the turn-on times is measured as a function of the pump rate of change and reveals no clear power law. This has motivated a detailed analysis of rate equations appropriate for two-state lasing QD lasers. We find that the effective time of the GS turn on follows an -1/2 power law provided that the rate of change is not too small. The effective time of the ES transition follows an -1 power law, but its first order correction in ln is numerically significant. The two turn ons result from different physical mechanisms. The delay of the GS transition strongly depends on the slow growth of the dot population, whereas the ES transition only depends on the time needed to leave a repellent steady state.

Iowa DOT's Infrastructure Annual Status Report 2017

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, Revenue Bonds Capitals and Revenue Bonds Capitals II.

Testosterone Therapy Differently Regulates The Anti- And Pro-inflammatory Cytokines In The Plasma And Prostate Of Rats Submitted To Chronic Ethanol Consumption (uchb).

Ethanol consumption damages the prostate, and testosterone is known by anti-inflammatory role. The cytokines were investigated in the plasma and ventral prostate of UChB rats submitted or not to testosterone therapy by ELISA and Western blot, respectively. Additionally, inflammatory foci and mast cells were identified in the ventral prostate slides stained by hematoxylin and eosin and toluidine blue, respectively. Inflammatory foci were found in the ethanol-treated animals and absent after testosterone therapy. Plasma levels of IL-6 and IL-10 were not changed while TNFα and TFG-β1 were increased in the animals submitted testosterone therapy. Regarding to ventral prostate, IL-6 did not alter, while IL-10, TNFα, and TFG-β1 were increased after testosterone therapy. Ethanol increases NFR2 in addition to high number of intact and degranulated mast cell which were reduced after testosterone therapy. So, ethanol and testosterone differentially modulates the cytokines in the plasma and prostate.

Neutralisation Of The Pharmacological Activities Of Bothrops Alternatus Venom By Anti-pla2 Iggs.

Basic phospholipases A2 (PLA2) are toxic and induce a wide spectrum of pharmacological effects, although the acidic enzyme types are not lethal or cause low lethality. Therefore, it is challenging to elucidate the mechanism of action of acidic phospholipases. This study used the acidic non-toxic Ba SpII RP4 PLA2 from Bothrops alternatus as an antigen to develop anti-PLA2 IgG antibodies in rabbits and used in vivo assays to examine the changes in crude venom when pre-incubated with these antibodies. Using Ouchterlony and western blot analyses on B. alternatus venom, we examined the specificity and sensitivity of phospholipase A2 recognition by the specific antibodies (anti-PLA2 IgG). Neutralisation assays using a non-toxic PLA2 antigen revealed unexpected results. The (indirect) haemolytic activity of whole venom was completely inhibited, and all catalytically active phospholipases A2 were blocked. Myotoxicity and lethality were reduced when the crude venom was pre-incubated with anti-PLA2 immunoglobulins. CK levels in the skeletal muscle were significantly reduced at 6 h, and the muscular damage was more significant at this time-point compared to 3 and 12 h. When four times the LD50 was used (224 μg), half the animals treated with the venom-anti PLA2 IgG mixture survived after 48 h. All assays performed with the specific antibodies revealed that Ba SpII RP4 PLA2 had a synergistic effect on whole-venom toxicity. IgG antibodies against the venom of the Argentinean species B. alternatus represent a valuable tool for elucidation of the roles of acidic PLA2 that appear to have purely digestive roles and for further studies on immunotherapy and snake envenoming in affected areas in Argentina and Brazil.