Sunflower Oil but Not Fish Oil Resembles Positive Effects of Virgin Olive Oil on Aged Pancreas after Life-Long Coenzyme Q Addition

An adequate pancreatic structure is necessary for optimal organ function. Structural changes are critical in the development of age-related pancreatic disorders. In this context, it has been reported that different pancreatic compartments from rats were affected according to the fat composition consumed. Since there is a close relationship between mitochondria, oxidative stress and aging, an experimental approach has been developed to gain more insight into this process in the pancreas. A low dosage of coenzyme Q was administered life-long in rats in order to try to prevent pancreatic aging-related alterations associated to some dietary fat sources. According to that, three groups of rats were fed normocaloric diets containing Coenzyme Q (CoQ) for two years, where virgin olive, sunflower, or fish oil was included as unique fat source. Pancreatic samples for microscopy and blood samples were collected at the moment of euthanasia. The main finding is that CoQ supplementation gives different results according to fat used in diet. When sunflower oil was the main fat in the diet, CoQ supplementation seems to improve endocrine pancreas structure and in particular β-cell mass resembling positive effects of virgin olive oil. Conversely, CoQ intake does not seem to improve the structural alterations of exocrine compartment previously observed in fish oil fed rats. Therefore CoQ may improve pancreatic alterations associated to the chronic intake of some dietary fat sources.     

Tartaglia–Pascal triangle and Brownian motion in non-euclidean geometries: application to heat and Black–Scholes equations

The recent worldwide explosion of the financial market originating also from the Black–Scholes equation proved how fundamental could be Brownian motion to real life. Brownian motion is deeply rooted into discrete spaces that are well represented by a Tartaglia–Pascal triangle (TPt). Furthermore, this mapping can be extended to the case of the Schrödinger equation: one of the key equations of quantum mechanics. The connection arises from the asymptotic formula for the binomial coefficients and the normal probability density function. This paper shows how this mapping between the discrete spaces, represented through some forms of TPt, extends to Brownian motion in different geometries. One of the well-known cases is the heat equation; another one is the Black–Scholes equation that derives from geometric Brownian motion. It is shown that the TPt becomes a periodic structure for the Brownian motion on a circle. For the geometric Brownian motion, we get a scale deformed TPt the main effect being scale deformations into the corresponding Newton binomial formula. In the asymptotic limit, one recovers the known formula for the sum on a row of the TPt. This approach unveils discrete structures underlying Brownian motion on different geometries revealing a possible conjecture that, for a given stochastic motion, it is always possible to associate a discrete map such that a TPt is obtained. In a general case, outcomes of the elements of the triangle become real numbers.     

Fluid Flow and Mechanisms of Momentum Transfer in a Six-Strand Tundish

Flow in a six-strand billet tundish, using turbulence inhibitors (TIs), was characterized using inputs of a pulsed tracer and mathematical simulations. It was found that to control turbulence attaining high fluid fractions under plug flow patterns, the key parameter for designing TIs is the dissipation rate of kinetic energy. TI designs that induce steep dissipation gradients are less efficient as flow controllers than those designs that yield more prolonged dissipation gradients from the inhibitor bottom to the bulk flow. A direct relationship between the dissipation of kinetic energy and the linear acceleration of the smallest turbulent eddies in the flow was established through dimensional analysis. The inhibitor with the highest linear accelerations of eddies in the viscous sublayer at the Kolmogorov scale, for a given liquid flow rate, yields the better flow control.     

Recognition by familiarity is preserved in Parkinson's without dementia and Lewy-Body disease.

Objective: The retrieval deficit hypothesis states that the lack of deficit in recognition often observed in patients with Parkinson's disease is because of the low retrieval requirements of the task, given that these patients have retrieval and not encoding deficits. To test this hypothesis we investigated recognition memory by familiarity in Parkinson's patients and in patients with Lewy Bodies disease and Parkinson with dementia. Method: We analyzed to what extent the experimental groups were able to recognize by familiarity in a typical yes/no recognition memory task. The experimental groups were patients with early nondemented Parkinson's disease, advanced nondemented Parkinson's disease, demented Parkinson's patients, and patients with dementia with Lewy Bodies. We compared their performance with a group of young and another group of old healthy participants. The estimation of familiarity was made by analyzing recognition of word targets and distractors consisting of combinations of different letters in comparison with a condition in which targets and distractors were composed of similar letters, even though subjects were unaware of the independent variable. Results: The results indicate that familiarity was used at the same level by controls, patients with early Parkinson's disease and patients with dementia with Lewy Bodies. Although late Parkinson patients also used familiarity, its effect was only marginally significant. Patients with Parkinson's disease and dementia were not capable of using familiarity in recognition memory. Conclusions: Our results support the retrieval deficit hypothesis as Parkinson's patients without dementia show no deficit in a situation in which the retrieval requirements are minimal. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The Cerro Prieto IV (Mexico) geothermal reservoir: Pre-exploitation thermodynamic conditions and main processes related to exploitation (2000–2005)

The Cerro Prieto IV (CP IV) reservoir, located in the northeastern part of the Cerro Prieto (Mexico) geothermal field, was studied in order to define its pre-exploitation conditions and initial (2000–2005) response to exploitation. Bottomhole thermodynamic conditions were estimated by modeling heat and fluid flows using the WELLSIM program and well production data. Produced fluid chemical and isotopic data were also analyzed to investigate characteristic patterns of behavior over time, which were then compared against simulation results to obtain a conceptual model of the CP IV reservoir. According to the proposed model, two zones in the reservoir – separated by Fault H and producing fluids of different characteristics – were identified under pre-exploitation conditions. Wells in the area to the east-southeast (south block) produce very high-enthalpy fluids (≥2000 kJ/kg), with very low chloride (≤7000 mg/kg) and high CO₂ (>6‰ molar) and δD (<−94‰). In contrast, wells toward the west-northwest (north block) show moderate-enthalpy fluids (1400–1800 kJ/kg), with high chloride (∼12,000 mg/kg) and relatively low CO₂ (<6‰ molar) and δD (<−94‰). Dilution caused by cooler water entry, boiling due to steam gain, both occurring in the north block, and steam condensation in the south block were identified as the three main reservoir processes associated with exploitation. Also, it was found that the dynamics of the CP IV reservoir is controlled by the Fault H system.     

Analysis and design process of a bi-membrane structure for micro-flow regulators

A bi-membrane structure is the main component of flow regulators for microfluidics with positive gain actuation. This microstructure is composed of two deformable circular membranes with different area tied by a rigid link that makes them move together. A comprehensive analysis of this microstructure is presented in this paper, which also provides an easy and practical design process in microsystems. The study is based on the microstructure behavior in typical microfluidic networks and is presented using dimensionless plots which have been obtained by numerical simulations based on finite element method performed by CoventorWare. The microstructure is defined using four dimensionless numbers for its seven dimensional parameters, and a dimensionless pressure. This fact represents the universal character of the design, dividing it into geometrical and material parts. The dimensionless pressure allows the use of any homogeneous and isotropic material in the design process of the devices. The values obtained from the plots are compared with simulation results using specific materials and dimensions and these comparisons present good agreement. Using the proposed analysis and design process, this sort of microstructures can be used by MEMS designers as standard components in microfluidic devices.     

Wind park reliable energy production based on a hydrogen compensation system. Part II: Economic study

Power production from renewable energy resources is increasing day by day. In the case of Spain, in 2009 it represented 26.9% of installed power and 20.1% of energy production. Wind energy makes the most important contribution to this production. Wind generators are greatly affected by the restrictive operating rules of electricity markets because, as wind is naturally variable, wind generators may have serious difficulties in submitting accurate generation schedules on a day-ahead basis, and in complying with scheduled obligations. Weather forecast systems have errors in their predictions depending on wind speed. Therefore, if wind energy becomes an important actor in the energy production system, these fluctuations could compromise grid stability. In the previous paper in this brief series [1], the authors showed technical results of the proposed solution, which consists of combining wind energy production with a biomass gasification system and a hydrogen generation system based on these two sources. In the present paper it is shown the economic results of the study, considering the most profitable technical configurations and three possible economic scenarios.     

Chemiluminescence Detection of 2,4,5-Trichlorophenoxy Acetic Acid in Apple Juice by Digital Image Analysis

An image-based detection of an enhanced chemiluminescence enzyme-linked immunosorbent assay was developed for 2,4,5-trichlorophenoxy acetic acid with an anti-rabbit secondary antibody conjugated to peroxidase (goat anti-rabbit IgG–HRP). Data acquisition on microtiter wells is performed using a low-cost charge-coupled device camera for capturing images. The standard curve was produced for 0.01–5,000 ng mL⁻¹ of 2,4,5-trichlorophenoxy acetic acid. The minimum detectable concentration was 24 pg mL⁻¹, and the relative standard deviation was 5.5% (n = 10) for a 5 ng mL⁻¹ sample concentration. Similar sensitivity was obtained with enzyme-linked immunosorbent assay using the same polyclonal antibody and data acquisition by a spectrofluorometer. This method was applied to apple juice with recoveries between 95% and 111% and relative standard deviation between 6.1% and 11.3%.     

An Individual Carbon Nanotube Transistor Tuned by High Pressure

A transistor based on an individual multiwalled carbon nanotube is studied under high‐pressure up to 1 GPa. Dramatic effects are observed, such as the lowering of the Schottky barrier at the gold–nanotube contacts, the enhancement of the intertube conductance, including a discontinuity related to a structural transition, and the decrease of the gate hysteresis of the device.