Technological and spoiling characteristics of the yeast microflora isolated from Bella Di Cerignola table olives

This study focused to investigate the technological significance and the spoiling impact of diverse yeast strains, isolated from 'Bella di Cerignola' Italian table olives. Sixty-four isolates (belonging mainly to the species Candida famata and C. guilliermondii ) were studied to assess their growth at different temperatures (15, 25 and 37 °C), pHs (4.0, 5.0 and 9.5) and NaCl concentrations (0–10.0%) in lab medium. Their pectolytic, xylanolytic, lipolytic and catalase activities were also evaluated. Most of the yeasts showed a moderate pectolytic activity and were able to grow at pH 9.5 after 120 h of incubation. Salt and temperature were the most important environmental variables affecting yeast growth, which could exert a strong selective pressure on yeast population. Candida guilliermondii appeared more resistant to high salt concentrations, whereas C. famata was able to grow at 15 °C.     

Effects of practice on character-classification performance.

Presented a character-classification task to 7 male college students under conditions of limited practice consistent with the characterization of memory search as a high-speed internal exhaustive serial comparison process having an average rate of 25-30 symbols/sec. Ss each performed under 3 positive set size conditions on each of 30 sessions. Results indicate that throughout sessions (a) the relationship between set size and response latency remained linear; (b) equality of slopes obtained from positive and negative trials was maintained; and (c) the estimate of scanning rate was stable, and its absolute value almost identical to previous values obtained with limited practice. (French summary) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Correlates of household smoking bans among Chinese Americans.

No population-based data are available on the degree to which Chinese Americans have adopted smoke-free household policies and whether these policies are effective in reducing environmental tobacco smoke (ETS) exposure. The present study examines the prevalence of smoke-free home rules among Chinese Americans living in New York City, describes predictors of adopting full smoking bans in the home, and explores the association between household smoking restrictions and ETS exposure at home. In-person interviews using a comprehensive household-based survey were conducted with 2,537 adults aged 18-74 years. Interviews were conducted in Mandarin, Cantonese, and other Chinese dialects. A total of 66% of respondents reported that smoking was not allowed inside the home, 22% reported a partial ban on smoking in the home, and 12% reported no smoking ban. Among current smokers, 38% reported a full household smoking ban. Current smoking status was the strongest predictor of less restrictive household smoking policies. Knowledge of the dangers of ETS, support of smoke-free air legislation, years in the United States, gender, income, and marital status also were associated with household smoking bans. Those living with a total household smoking ban were significantly less likely to report 30-day exposure to ETS than were those living in homes with a partial ban or no ban (7% vs. 68% and 73%, respectively). In homes of smokers and nonsmokers alike, exposure to ETS remains high. Smoke-free home rules and interventions among smokers and nonsmokers to raise awareness of the dangers of ETS have the potential to significantly reduce exposure to household ETS among this immigrant population.     

Studies on the mechanical degradation of cellulose

The mechanical degradation by high-speed stirring of cellulose in dilute n-butanol suspensions was investigated on six different samples with degrees of polymerization (DP) between 300 and 7500. The degrees of polymerization were determined viscosimetrically in CuEn (copper ethylendiamine complex) at different times of mechanical action. The distributions of the DP were measured on the polymer-analogous nitrates by size exclusion chromatography (HPSEC) in THF. The investigations reveal that only high-molecular-weight cellulose undergoes degradation, whereas celluloses with a starting DP₀ < 3000 remain undegraded. In the case of degradation the decrease of the DP with time is exponential, reaching a “limiting” DP (DP_∞) of about 3200 which does not diminish further. The narrowing with degradation time of the distributions of DP of the degraded samples allows to assume that the bonds splitting by the action of mechanical forces are the so-called “weak links” present in high-molecular-weight cellulose. The course of the nonuniformity U with decreasing DP, could be confirmed by mathematical derivation of the relationship between U and the degree of degradation DP₀/DP_t, considering the scission of only “weak links”.     

Nanostructured electrochemical sensors based on functionalized nanoporous silica for voltammetric analysis of lead, mercury, and copper

We have successfully developed electrochemical sensors based on functionalized nanostructured materials for voltammetric analysis of toxic metal ions. Glycinylurea self-assembled monolayers on mesoporous silica (Gly-UR SAMMS) were incorporated in carbon paste electrodes for the detection of toxic metal ions such as lead, copper, and mercury based on adsorptive stripping voltammetry (AdSV). The electrochemical sensor yields a linear response at a low ppb level of Pb2+ (i.e., 2.5-50 ppb) after a 2-min preconcentration period, with reproducible measurements (%RSD = 3.5, N = 6) and an excellent detection limit (1 ppb). By exploiting the interfacial functionality of Gly-UR SAMMS, the sensor is selective for the target species, does not require the use of a mercury film, and can be easily regenerated in dilute acid solution. The rigid, open, parallel pore structure, combined with suitable interfacial chemistry of SAMMS, also results in fast analysis times (2-3 min). The nanostructured SAMMS materials enable the development of miniature sensing devices that are compact and low cost, have low energy consumption, and are easily integrated into field-deployable units.     

Microbial catabolic diversity in soils contaminated with hydrocarbons and heavy metals

Understanding indigenous microbial function in contaminated soil is crucial to the successful development and use of bioremediation technologies. We measured the catabolic diversity of indigenous microbial communities in soils with a 30-yr history of Pb, Cr, and hydrocarbon (HC) contamination using a modified substrate-induced respiration method. There were characteristic differences of microbial respirations in the response of highly versus less contaminated soils to the range of organic substrates used. The catabolic response to glucose as compared to succinic acid was approximately 1:5 in less contaminated soils, but 1:25 in highly contaminated soils. In contrast, the response ratio to glucose versus aromatics was about 1:0.4 in less contaminated soils and 1:1 in highly contaminated soils. Principal components analysis (PCA) of the responses confirmed that catabolic diversity differed between highly and less contaminated soils. Univariate analysis also indicated that catabolic diversity was reduced in highly contaminated soils. This catabolic difference was strongly associated with the alteration of microbial community composition. Statistical analyses suggested that the variation in microbial community catabolic diversity was attributed to HCs more than to Pb and Cr.     

The application of a thermochemical data bank system to the investigation of steel-making problems

The advantages associated with the application of a thermochemical data bank system to the investigation of metallurgical and chemical processes are described. In particular, the ready availability of up-to-date, critically evaluated data which may be used in conjunction with specially-written application programs, enables the user to obtain information very rapidly at his own terminal in the tabular or graphical form he requires. The use of such a data bank for carrying out calculations related to certain steel-making problems is demonstrated – namely for guiding deoxidation and desulphurisation operations, for investigating the conditions for formation of precipitated carbide and nitride phases in alloy steels, for determining the effect of alloying elements on hydrogen solubility in iron, and for predicting likely corrosion products in different gaseous environments.     

Use of Lactobacillus plantarum and glucose to control the fermentation of "Bella di Cerignola" table olives, a traditional variety of Apulian region (Southern Italy)

The purpose of this study was to evaluate the use of Lactobacillus plantarum, isolated from table olives "Bella di Cerignola," a traditional variety of Apulian region (Southern Italy), as a starter for this kind of food. We focused on the interaction of the starter with the natural occurring microflora, the quantitative/qualitative composition of yeast population, the decrease of pH, and the content of organic acids. After a preliminary characterization, 3 strains of Lb. plantarum, selected for their probiotic and technological performances, were used as a multiple-strain starter and inoculated (approximately 2%) in olives, processed according to Spanish style, brined at 8% and 10% of NaCl and added with 0.5% of glucose. The combination of the starter and glucose assured a correct fermentation course, decreasing the pH up to a safe value (4.3 to 4.5) and controlled the growth of yeasts. The concentrations of both L- and D-lactic acids increased throughout the fermentation, while citric and malic acids (both the isomers D and L) remained at low levels (0.2 to 0.4 g/L). Concerning yeast species, Candida guilliermondii was mainly isolated at the beginning (7 to 14 d), while C. famata prevailed at the end of fermentation. PRACTICAL APPLICATIONS: To the question "How to standardize and maintain quality of "Bella di Cerignola" olives (Southern Italy)" we can suggest the following answer: use Lb. plantarum and a low amount of glucose (0.5%). The result is a decrease of the pH below the safety break point.     

Optical fibre dosemeter systems for clinical applications based on radioluminescence and optically stimulated luminescence from Al2O3:C

Optical fibre dosemeter systems based on radioluminescence and optically stimulated luminescence (OSL) from carbon-doped aluminium oxide (Al(2)O(3):C) crystals were developed for in vivo real-time dose rate and absorbed dose measurements in radiotherapy and mammography. A technique was also developed for making ultra-small dosemeter probes that can easily be placed inside patients in radiation treatment. These probes have shown excellent properties in both head and neck intensity-modulated radiation therapy treatment and in mammography. The dose-response of the OSL signal for the new optical fibre dosemeter system showed a repeatability within 0.15% at a dose level of 60 mGy when integrated over 100 s. The temperature dependence in the range 0-45 degrees C showed a reproducibility within 1.3% when the OSL signal was integrated over 100 s.