Characterization of a Torulaspora delbrueckii diploid strain with optimized performance in sweet and frozen sweet dough

Torulaspora delbrueckii is a baker's yeast that is highly tolerant to freeze-thaw stress, making it suitable for frozen dough technology. The T. delbrueckii strain PYCC5321, isolated from traditional bread dough, combines this tolerance with a high degree of ionic and osmotic stress resistance. However, the industrial use of this strain for frozen and sweet frozen baking is hampered by its small cell size, which causes clogging problems at the filtering stage. Here, we report the construction of a stable diploid strain of T. delbrueckii PYCC5321, which we named Td21-2n. The new strain was more than 2.7-fold bigger than their haploid counterpart, whereas biomass yield, stress resistance and sweet dough leavening ability were found to be similar in both strains. Moreover, the gassing power of the diploid after dough freezing also remained unaltered. Thus, Td21-2n meets the requirements necessary for industrial production and is suitable for application in frozen sweet baking products.     

Improved equivalent circuit and analytical model for amorphoussilicon solar cells and modules

An improved equivalent circuit for hydrogenated amorphous silicon (a-Si:H) solar cells and modules is presented. It is based on the classic combination of a diode with an exponential current-voltage characteristic, of a photocurrent source plus a new term representing additional recombination losses in the i-layer of the device. This model/equivalent circuit matches the I(V) curves of a-Si:H cells over an illumination range of six orders of magnitude. The model clearly separates effects related to the technology of the device (series and parallel resistance) and effects related to the physics of the p-i-n junction (recombination losses). It also allows an effective μτ product in the i-layer of the device to be determined, characterizing its state of degradation     

Optimization of hydrocolloid addition to improve wheat bread dough functionality: a response surface methodology study

Effects of high ester pectin+α-amylase+sucrose (GNFZ), a high ester pectin+sucrose (BIG), xanthan gum (XANTHAN) and hydroxypropylmethylcellulose (HPMC) on wheat dough performance have been studied. Effects of hydrocolloids added singly and in association at different levels, on the investigated rheological, mechanical and thermal parameters have been evaluated by response-surface methodology. Optimum hydrocolloid formulations for white wheat bread are recommended.Positive linear and negative quadratic significant effects of GNFZ were observed on both the gluten index (GI) and the energy of dissociation of the amylose–lipid complex (ΔH_x). Optimized dosage of 1.36 g GNFZ/100 g flour, d.b. (maximum of the respective response surface plot) led to maximized values for both GI and ΔH_x, described as good indicators and predictors of the quality of fresh and stored formulated breads to be obtained. The strengthening effect of high ester pectin was reinforced by the negative quadratic effect of GNFZ on gluten extensibility, the positive effect of GNFZ/HPMC on the resistance to extension of gluten, and the negative synergistic effect of the pair BIG/HPMC on dough extensibility. XANTHAN when added singly induced desirable increase in dough resistance to extension, and the incorporation of the pair XANTHAN/GNFZ into dough formula is recommended because of the reduction of the induced degree of softening during mixing (farinograph) of GNFZ formulated doughs. A dosage of 0.109 g XANTHAN/100 g flour annulate the softening effect of GNFZ when added at an optimized dose of 1. 36 g GNFZ/100 g flour. Caution should be applied when added XANTHAN in presence of BIG because of the decrease in the extent of amylose–lipid complexation. Addition of HPMC at a level <1/>1 moderate/enhance, respectively, the effect of GNFZ on the resistance to extension of the gluten, and the water binding capability of BIG, and in this respect the incorporation of the cellulose derivative is encouraged at a dose dependent on the required effect.     

Solving the steady‐state groundwater flow equation for finite linear aquifers using a generalized Fourier series approach in two‐dimensional domains

A method to solve steady linear groundwater flow problems using generalized Fourier Series is developed and particularized for multiple Fourier series in two‐dimensional domains. It leads to a linear vector equation whose solution provides a finite number of generalized Fourier coefficients approximating the hydraulic head field. Its implementation is shown and two relevant properties are found for the system matrix. It is always symmetric and, once computed, if additional Fourier terms are needed for a better approximation of the hydraulic head field, previously computed matrix elements remain invariant, i.e. only new rows and columns are added to the system matrix. The method is demonstrated in three simple cases with different geometries and transmissivity fields, where solutions are compared with analytical and finite element method results. Thus, the method is verified as an alternative to other flow solvers. Additionally, it provides a direct way to obtain the spectral form of the flow equation solution, given a spectral representation of transmissivity, and can be easily extended to obtain continuous velocity fields and their approximated spectral expressions. Copyright © 2009 John Wiley & Sons, Ltd.     

Geographical information systems for map based navigation in urban environments

In order to solve most of the existing mobile robotics applications, the robot needs some information about its spatial environment encoded in what it has been commonly called a map. The knowledge contained in such a map, whatever approach is used to obtain it, will mainly be used by the robot to gain the ability to navigate in a given environment. We are describing in this paper, a method that allows a robot or team of robots to navigate in large urban areas for which an existing map in a standard human understandable fashion is available. As detailed maps of most urban areas already exist, it will be assumed that a map of the zone where the robot is supposed to work is given, which has not been constructed using the robot’s own sensors. We propose in this paper, the use of an existing Geographical Information System based map of an urban zone so that a robot or a team of robots can connect to this map and use it for navigation purposes. Details of the implemented system architecture as well as a position tracking experiment in a real outdoor environment, a University Campus, are provided.     

Hydrotreatment of Cracked Light Gas Oil

Since worldwide conversion processes are used to upgrade heavy oil to distillates, the hydrotreatment of light gas oil (LGO) as a downstream process has been used more extensively. This fraction (LGO) is produced from thermal or catalytic cracking or hydrocracking processes. It contains high amounts of unsaturates, nitrogen, and sulfur compounds which cause instability while in storage due to gum formation. The use of LGO as a fuel oil for diesel engines plugs the filter and produces sulfur and nitrogen emissions. These sulfur and nitrogen compounds arise from the cracking of heavy cuts and are aromatic-type molecules which are difficult to hydrogenate. This cut also possesses a low cetane index (CI) which must be increased (by aromatic hydrogenation) because of its poor motor performance. Color and color stability are associated with a high bromine number (BN, unsaturated content), nitrogen, and aromatic content. In order to improve these properties, a deep hydrogenation is sometimes required.     

Designing a benchmark for the performance evaluation of agent-based simulation applications on HPC

The Journal of Supercomputing - Agent-based modeling and simulation (ABMS) is a class of computational models for simulating the actions and interactions of autonomous agents with the goal of...     

Autologous stem-cell transplantation for non-Hodgkin's lymphomas: the role of graft purging and radiotherapy posttransplantation--results of a retrospective analysis on 120 patients autografted in a single institution

PURPOSE: To analyze retrospectively survival and prognostic factors of patients with non-Hodgkin's lymphoma (NHL) autografted from 1979 to 1995 in a single institution. PATIENTS AND METHODS: A total of 120 patients, 64 with aggressive and 56 with low-grade NHL, were autografted. The carmustine (BCNU), etoposide, cytarabine, and melphalan (BEAM) regimen was used in 104. The autograft was marrow in 101 patients. Marrow was purged in vitro by mafosfamide for 63 patients (adjusted dose [AD] in 32; unique dose [UD] in 31); 27 patients received a CD34+-selected graft. Following intensification, 45 patients received additional radiotherapy on previous sites of involvement. RESULTS: Outcome at 5 years for patients transplanted with low-grade NHL in first complete remission (CR1), in first partial remission (PR1), and in second complete remission (CR2) or beyond showed an event-free survival (EFS) of 75% +/- 12%, 46% +/- 18%, and 57% +/- 24%, a relapse incidence (RI) of 21% +/- 12%, 49% +/- 19%, and 43% +/- 25%, and a transplant-related mortality (TRM) of 5% +/- 5%, 10% +/- 7%, and 0%, respectively. For patients with aggressive NHL transplanted in CR1, in PR1, in CR2 or beyond, and in resistant relapse or in primary refractory disease, the EFS was of 73% +/- 9%, 58% +/- 19%, 29% +/- 16%, and 10% +/- 9%, the RI 22% +/- 9%, 14% +/- 9%, 77% +/- 18%, and 66% +/- 20%, and the TRM 6% +/- 6%, 32% +/- 21%, 11% +/- 10%, and 71% +/- 22%, respectively. In patients autografted upfront in first remission, additional radiotherapy was associated with a higher EFS, in univariate (P = .03) and multivariate analysis (P = .02, relative risk [RR] = .021). The role of graft purging with mafosfamide on the outcome reflected by the dose of colony-forming unit-granulocyte-macrophage (CFU-GM) per kilogram infused postpurging was assessed by univariate analysis: patients in first remission who received lower doses of CFU-GM had a lower RI and a higher EFS. CONCLUSION: This retrospective analysis suggests that marrow purging and posttransplant radiotherapy improve the outcome of patients with NHL autografted in first remission.