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61.
Mónica?FloresEmail author Pablo?Nieto José?Manuel?Ferrer José?Flores 《European Food Research and Technology》2005,221(5):624-630
The effect of calcium chloride addition used in combination with starter cultures (lactic acid bacteria and staphylococci)
was studied in the development of dry-fermented sausage aroma and final sensory acceptance. Volatile compounds were extracted
by solid-phase micro extraction and analysed by gas chromatography-mass spectrometry. A paired comparison test was done to
determine which sausage was preferred. The addition of calcium chloride 0.05% showed an important effect on volatile generation
during ripening by inhibiting the generation of lipid oxidation products and promoting the generation of methyl branched alcohols
and ethyl esters that contribute to proper sausage aroma. However, other compounds such as 3-methyl-butanoic acid and acetic
acid, detected in high quantities in the 0.05% calcium added batch, may impart rancid and cheese-like notes that can negatively
affect the final aroma. Moreover, the amount of calcium chloride used is important because larger amounts (0.5%) favoured
the lipid oxidation producing a rejection from consumers. 相似文献
62.
Catalytic wet oxidation has proved to be effective at eliminating hazardous organic compounds, such as phenol, from waste waters. However, the lack of active long-life oxidation catalysts which can perform in aqueous phase is its main drawback. This study explores the ability of bimetallic supported catalysts to oxidize aqueous phenol solutions using air as oxidant. Combinations of 2% of CoO, Fe2O3, MnO or ZnO with 10% CuO were supported on gamma-alumina by pore filling, calcined and later tested. The oxidation was carried out in a packed bed reactor operating in trickle flow regime at 140 degrees C and 900 kPa of oxygen partial pressure. Lifetime tests were conducted for 8 days. The pH of the feed solution was also varied. The results show that all the catalysts tested undergo severe deactivation during the first 2 days of operation. Later, the catalysts present steady activity until the end of the test. The highest residual phenol conversion was obtained for the ZnO-CuO, which was significantly higher than that obtained with the 10% CuO catalyst used as reference. The catalyst deactivation is related to the dissolution of the metal oxides from the catalyst surface due to the acidic reaction conditions. Generally, the performance of the catalysts was better when the pH of the feed solution was increased. 相似文献
63.
64.
Carlos Romero‐Nieto Stefan Durben Ila M. Kormos Thomas Baumgartner 《Advanced functional materials》2009,19(22):3625-3631
This paper describes a structure–property study using two dithieno[3,2‐b;2′,3′‐d]phosphole building blocks for the generation of white light emission and the incorporation of these units in a single polystyrene material. The emission of one of the light‐emitting organophosphorus building blocks can efficiently be switched from orange to green by simple protonation of the amino functional groups that are part of the π‐conjugated scaffold. The resulting three components (blue, green, and orange) exhibit photophysical properties that allow for an efficient fluorescence resonance energy transfer (FRET) in the mixture/polymer and provide intense white fluorescence upon excitation of the blue component; the fluorescence is close to pure white in solution and similar to the emission of an incandescent light bulb in the thin film. The results nicely illustrate the intriguing features that can be obtained by exclusively using organophosphorus‐based organic electronic materials. 相似文献
65.
Optimal haulage routing of off-road dump trucks in construction and mining sites using Google Earth and a modified least-cost path algorithm 总被引:2,自引:0,他引:2
This study presents new software, called Google Earth-based Optimal HAulage RouTing System (GEOHARTS), to improve the functionality of Google Earth for optimal haulage routing of off-road dump trucks in construction and mining sites. A modified least-cost path algorithm, which is applicable to working areas with both paved and unpaved temporary roads and can consider the effects of terrain relief and curves along a route on the route planning, was proposed and utilized for the software development. GEOHARTS can determine optimal haulage routes between loaders and dumps that ensure the least travel time or fuel consumption of off-road dump trucks and can visualize the results using an embedded 3D render window of Google Earth. The application to the Pasir open-pit coal mine in Indonesia demonstrates that GEOHARTS could provide a rational solution to support the truck haulage operations. 相似文献
66.
SF Quan BV Howard C Iber JP Kiley FJ Nieto GT O'Connor DM Rapoport S Redline J Robbins JM Samet PW Wahl 《Canadian Metallurgical Quarterly》1997,20(12):1077-1085
The Sleep Heart Health Study (SHHS) is a prospective cohort study designed to investigate obstructive sleep apnea (OSA) and other sleep-disordered breathing (SDB) as risk factors for the development of cardiovascular disease. The study is designed to enroll 6,600 adult participants aged 40 years and older who will undergo a home polysomnogram to assess the presence of OSA and other SDB. Participants in SHHS have been recruited from cohort studies in progress. Therefore, SHHS adds the assessment of OSA to the protocols of these studies and will use already collected data on the principal risk factors for cardiovascular disease as well as follow-up and outcome information pertaining to cardiovascular disease. Parent cohort studies and recruitment targets for these cohorts are the following: Atherosclerosis Risk in Communities Study (1,750 participants), Cardiovascular Health Study (1,350 participants), Framingham Heart Study (1,000 participants), Strong Heart Study (600 participants), New York Hypertension Cohorts (1,000 participants), and Tucson Epidemiologic Study of Airways Obstructive Diseases and the Health and Environment Study (900 participants). As part of the parent study follow-up procedures, participants will be surveyed at periodic intervals for the incidence and recurrence of cardiovascular disease events. The study provides sufficient statistical power for assessing OSA and other SDB as risk factors for major cardiovascular events, including myocardial infarction and stroke. 相似文献
67.
PJ Cagnoni Y Nieto EJ Shpall SI Bearman AE Barón M Ross S Matthes SE Dunbar RB Jones 《Canadian Metallurgical Quarterly》1998,16(5):1661-1668
PURPOSE: To evaluate the feasibility of high-dose chemotherapy (HDC) with autologous hematopoietic progenitor-cell support (AHPCS) as part of combined modality therapy (CMT) in patients with inflammatory breast cancer (IBC). PATIENTS AND METHODS: From April 1993 to March 1997, 30 patients with IBC were treated at our program. Twenty-three patients received neoadjuvant chemotherapy (NAC) before HDC; 18 patients also received adjuvant chemotherapy following surgery, but before HDC. All patients received HDC with high-dose cyclophosphamide, cisplatin, and carmustine (BCNU) with AHPCS. Every patient underwent surgery either before (27 patients) or after (three patients) HDC. Patients received radiotherapy after HDC in addition to tamoxifen if their tumors were estrogen receptor-positive. RESULTS: Thirteen patients experienced grade 3 or 4 nonhematologic noninfectious toxicities. In 12 patients (40%), this represented drug-induced lung injury, which in all cases responded to a 10-week course of corticosteroids. The only treatment-related death was secondary to hemolytic-uremic syndrome (HUS). Another patient suffered grade 4 CNS toxicity, which was completely reversible. All patients engrafted promptly. Eight patients relapsed, five of whom had a poor pathologic response to NAC. Relapses were local (five patients), local plus systemic (one), or systemic only (two). Median follow-up time from diagnosis and HDC is 23.5 (range, 7 to 49) and 19 (range, 4 to 44) months, respectively. Twenty-one patients (70%; 95% confidence interval [CI], 51% to 86%) remain alive and free of disease 4 to 44 months after HDC. Median disease-free survival (DFS) and overall survival have not yet been reached. CONCLUSION: HDC as part of CMT is feasible in patients with IBC. The toxicity of this treatment program is significant, but tolerable. Despite the short follow-up duration, the promising DFS observed in this group of patients warrants randomized studies that include a HDC-containing arm in patients with IBC. 相似文献
68.
Forecasting airborne pollen concentration time series with neural and neuro-fuzzy models 总被引:3,自引:0,他引:3
Jos Luis Aznarte M. Jos Manuel Benítez Snchez Diego Nieto Lugilde Concepcin de Linares Fernndez Consuelo Díaz de la Guardia Francisca Alba Snchez 《Expert systems with applications》2007,32(4):1218-1225
Forecasting airborne pollen concentrations is one of the most studied topics in aerobiology, due to its crucial application to allergology. The most used tools for this problem are single lineal regressions and autoregressive models (ARIMA). Notwithstanding, few works have used more sophisticated tools based in Artificial Intelligence, as are neural or neuro-fuzzy models. In this work, we applied some of these models to forecast olive pollen concentrations in the atmosphere of Granada (Spain). We first studied the overall performance of the selected models, then considering the data segmented into intervals (low, medium and high concentration), to test how they behave on each interval. Experimental results show an advantage of the neuro-fuzzy models against classical statistical methods, although there is still room for improvement.1 相似文献
69.
J Figueras D Parés H Aranda A Rafecas J Fabregat J Torras E Ramos C Lama L Lladó E Jaurrieta 《Canadian Metallurgical Quarterly》1997,64(4):655-658
Parkinson's disease (PD) patients often develop dementia, and Alzheimer's disease (AD) patients frequently develop parkinsonian signs. The apolipoprotein E epsilon4 allele is associated with increased risk and earlier onset of AD. We studied 137 unrelated white PD patients. Those with epsilon4 had the earliest onset (52.7 +/- 9.8 years), epsilon3/epsilon3 patients had an intermediate onset (56.1 +/- 11.1 years), and those with epsilon2 had the latest onset (59.1 +/- 13.4 years). The age at onset distribution for epsilon4/epsilon- was significantly earlier than for epsilon3/epsilon3 and epsilon2/epsilon3. These preliminary results suggest that apolipoprotein E genotypes modulate the age at onset of PD. 相似文献
70.
Small addition of potassium to a Mo–V–Sb mixed oxide catalyst (previously prepared by hydrothermal synthesis) strongly modifies its catalytic behavior. Thus, while acetic acid is mainly observed in the K-free catalysts, acrylic acid is selectively obtained in K-doped catalysts. In this case, a selectivity to acrylic acid of about 30% is achieved at propane conversions of 30%. This catalytic behavior is apparently not due to modification of the crystalline phases in the K-doped catalysts but to the elimination of the acid sites of the undoped Mo–V–Sb mixed oxide catalyst. 相似文献