Microbial Challenges to Extending Usage of Rio Grande River Water

Despite its critical role in agriculture and potable water supply for the region, few studies have evaluated the microbial quality of the Rio Grande River, especially for the parasites Cryptosporidium and Giardia. Cryptosporidium and Giardia cause diarrheal illness and have been responsible for numerous waterborne and foodborne disease outbreaks. Cryptosporidiosis, the disease caused by Cryptosporidium, may be fatal in people with weakened immune systems and there is currently no effective treatment for the disease. During the irrigation season, water is released from upstream reservoirs and the river water is used by El Paso as a potable supply. During the non-irrigation season (October through February), river flows are comprised of agricultural return flows and wastewater treatment plant effluents. Due to recent drought conditions in the region, winter return flows in the El Paso area are largely wastewater effluents. Our monitoring results revealed that winter return flows contain 5 and 100 times higher average levels of Cryptosporidium and Giardia, respectively, than irrigation season river water. Recently, research has been proposed to evaluate the use of winter return flows for potable supply and irrigation. Conventional filtration and disinfection followed by nanofiltration or reverse osmosis have been proposed for treatment of the water to remove total dissolved solids and microorganisms. Besides Cryptosporidium and Giardia, viruses may also be present in wastewater effluents. Therefore, in addition to chemical quality issues, these microbial water quality challenges must be overcome before this underutilized water resource can be put to beneficial use

The role of positive attitudes, satisfaction and joy or living as elements of happiness

Articulo cientificoThe difficulty in defining happiness has allowed the identification and study of various elements that try to describe it; among these elements there is satisfaction with life, positive affect, personality traits, expectations, and needs. The purpose of this study is to identify the relationship between four of the variables that have been linked to happiness: satisfaction with life, joy of living, personal fulfillment and positive sense of life, using structural equation models (SEM). The Happiness Scale of Lima was applied to 1083 adults. The results show that only three of the proposed elements are related: positive sense of life, satisfaction with life, and joy of living, whereas personal fulfillment is part of the judgments the participants made about their own lives

Role of dopamine tone in brain stimulation reward

The experiments described in the present thesis address the specific role of dopamine (DA) tone in brain stimulation reward (BSR). The level of extracellular dopamine in the rat nucleus accumbens was measured by means of in-vivo microdialysis in rats receiving electrical stimulation of the medial forebrain bundle. The first experiments characterize changes in DA tone as a function of reward predictability and duty cycle under circumstances in which phasic release of DA, as measured by fast-scan cyclic voltammetry, has been reported to be absent (Garris et al., 1999). The results obtained using several different reinforcement schedules suggest that DA tone reflects the duty cycle of the stimulation rather than the predictability of the reward. In contrast to the transient elevation observed when stimulation is delivered at short (1.5 s) inter-train intervals, stimulation trains separated by long (12 s) inter-train intervals can sustain a stable level of DA tone for up to two hours. This difference in the stability of DA tone has repercussions for the behaviour sustained by BSR, as measured by means of the curve-shift paradigm. When DA tone was measured under similar circumstances to those in the Garris et al. (1999) study, a robust increase in tonic DA release was observed, on each schedule tested, in sharp contrast to the transient changes in phasic DA release described by Garris et al. (1999). These results suggest that phasic and tonic DA release are under differential control. In an additional experiment, the reinforcement-mountain model and testing paradigm were used to determine the stage(s) of processing at which DA tone influences the pursuit of BSR. The mountain model relates pursuit of BSR to the cost and strength of the electrical stimulation. DA reuptake was blocked by continuous subcutaneous infusion of cocaine in a novel manner that avoids tissue damage. The 3D structure defined by time-allocation, reward cost and reward strength. always shifted rightward along the cost axis but rarely along the strength axis. This result implies that the leftward shifts seen in "rate-frequency" studies of the effect of cocaine on intracranial self-stimulation (ICSS) are misleading: these effects are due to displacement of the diagonally oriented face of the 3D structure along the cost axis. The results demonstrate that DA tone exerts its influence at a later processing stage than originally proposed and long believed

Contrasting Effects of Lithium Chloride and CB1 Receptor Blockade on Enduring Changes in the Valuation of Reward

When an organism responds for a reward, its learned behavior can be characterized as goal-directed or habitual based on whether or not it is susceptible to reward devaluation. Here, we evaluated whether instrumental responding for brain stimulation reward (BSR) can be devalued using a paradigm traditionally used for natural rewards. Rats were trained to lever press for BSR; afterward, BSR was paired with either lithium chloride (LiCl, 5 mg/kg, i.p.), a pro-emetic, or AM251, a CB1 receptor antagonist (3 mg/kg, i.p.) or the vehicle of these compounds. Pairings of BSR with these compounds and their vehicles were performed in a novel environment so that only unconditional effects of BSR would be affected by the pharmacological manipulations. Subsequently, in a probe test, all rats were returned in the drug-free state to the boxes where they had received training and instrumental responding was reassessed in the absence of BSR delivery. When compared to control, LiCl produced a significant decrease in the number of responses during the test session, whereas AM251 did not. These results show that instrumental responding for BSR is susceptible to devaluation, in accord with the proposal that this behavior is supported at least in part by associations between the response and the rewarding outcome. Further, they suggest that reward modulation observed in studies involving the use of CB1 receptor antagonists arises from changes in the organism’s motivation rather than drug-induced changes in the intrinsic value of reward

Solución de dos escenarios presentes en entornos corporativos bajo el uso de tecnología CISCO

Gracias al desarrollo de esta actividad fue fundamental para poder aplicar nuestros conocimientos y desarrollar destrezas en el desarrollo de proyectos de este tipo, y que mejor manera que a través de la solución de estos 2 ESCENARIOS. Profundizaremos mucho más en el tema que tiene que ver con los diferentes medios de transmisión y los dispositivos intermedios que hacen parte de las redes y hacen posible la comunicación. Aplicare todo el conocimiento adquirido en lo que tiene que ver con el direccionamiento IP aplicando VLSM tanto para el direccionamiento IPV4 como también IPV6 y todo el tema relacionado con PROTOCOLOS DE ENRUTAMIENTO. Por nuestra modalidad de educación a distancia es de se hace fundamental la utilización del simulador de REDES PACKET TRACER la cual ha sido la posibilidad perfecta para las personas que no disponemos de esos dispositivos físicos podamos aplicar nuestros conocimiento y destrezas adquiridas.Thanks to the development of this activity, it was essential to be able to apply our knowledge and develop skills in the development of projects of this type, and what better way than through the solution of these 2 SCENARIOS. We will delve much more into the subject that has to do with the different transmission media and the intermediate devices that are part of the networks and make communication possible. I will apply all the knowledge acquired in what has to do with IP addressing applying VLSM for both IPV4 and IPV6 addressing and all the subject related to ROUTING PROTOCOLS. Due to our distance education modality, the use of the REDES PACKET TRACER simulator is essential, which has been the perfect possibility for people who do not have these physical devices to apply our knowledge and acquired skills

IRAC Observations of Taurus Pre-Main Sequence Stars

We present infrared photometry obtained with the IRAC camera on the Spitzer Space Telescope of a sample of 82 pre-main sequence stars and brown dwarfs in the Taurus star-forming region. We find a clear separation in some IRAC color-color diagrams between objects with and without disks. A few ``transition'' objects are noted, which correspond to systems in which the inner disk has been evacuated of small dust. Separating pure disk systems from objects with remnant protostellar envelopes is more difficult at IRAC wavelengths, especially for objects with infall at low rates and large angular momenta. Our results generally confirm the IRAC color classification scheme used in previous papers by Allen et al. and Megeath et al. to distinguish between protostars, T Tauri stars with disks, and young stars without (inner) disks. The observed IRAC colors are in good agreement with recent improved disk models, and in general accord with models for protostellar envelopes derived from analyzing a larger wavelength region. We also comment on a few Taurus objects of special interest. Our results should be useful for interpreting IRAC results in other, less well-studied star-forming regions.Comment: 29 pages 10 figures, to appear in Ap

A model for electrode effects based on adsorption theory

A model to describe the electrode effects based on the adsorption theory is proposed. We assume that the coverage (i.e by gas bubbles, electrodeposition of compounds, etc) of the electrodes is governed by a kinetics equation where the adsorption term is proportional to the bulk current density, and the desorption term to the actual coverage. The adsorption can take place only on the uncovered part of the electrode. We show that the coverage is responsible for a variation of the interface properties of the electrode. The time dependence of the electric response of the cell, submitted to an external voltage, is determined by solving the differential equation for the coverage. We show that two regimes are expected. One, in the limit of small time, controlled by the charging of the surface interface, and one related to the coverage. The theoretical predictions are in reasonable agreement with the experimental data concerning the time dependence of the current and the current-voltage characteristics of a home-made photo-electrolyzer constituted by a BiVO4 photoanode and a Pt cathode. Moreover, a normalized current-voltage curve was obtained, which fit also literature data based on (i) electrolysis on cylindrical stainless-steel electrodes in NaOH electrolyte and (ii) electrolytic plasma nitrocarburizing of AISI 1020 steel discs in an Urea-based aqueous solution, demonstrating the versatility and broad range of application of the here proposed model

The influence of N-terminal acetylation on micelle-induced conformational changes and aggregation of α-Synuclein

The biological function of α-Synuclein has been related to binding to lipids and membranes but these interactions can also mediate α-Synuclein aggregation, which is associated to Parkinson's disease and other neuropathologies. In brain tissue α-Synuclein is constitutively N-acetylated, a modification that plays an important role in its conformational propensity, lipid and membrane binding, and aggregation propensity. We studied the interactions of the lipid-mimetic SDS with N-acetylated and non-acetylated α-Synuclein, as well as their early-onset Parkinson's disease variants A30P, E46K and A53T. At low SDS/protein ratios α-Synuclein forms oligomeric complexes with SDS micelles with relatively low α-helical structure. These micellar oligomers can efficiently nucleate aggregation of monomeric α-Synuclein, with successive formation of oligomers, protofibrils, curly fibrils and mature amyloid fibrils. N-acetylation reduces considerably the rate of aggregation of WT α-Synuclein. However, in presence of any of the early-onset Parkinson's disease mutations the protective effect of N-acetylation against micelle-induced aggregation becomes impaired. At higher SDS/protein ratios, N-acetylation favors another conformational transition, in which a second type of α-helix-rich, non-aggregating oligomers become stabilized. Once again, the Parkinson's disease mutations disconnect the influence of N-acetylation in promoting this transition. These results suggest a cooperative link between the N-terminus and the region of the mutations that may be important for α-Synuclein function