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.     

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.     

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.     

Any link between integrin degradation and water-holding capacity in pork?

In order to investigate a possible relationship between integrin degradation and water-holding capacity (WHC), integrin was quantified using western blot, and water mobility and distribution was measured by proton NMR T(2) relaxometry at 24h postmortem in pork (n=30) with a large variation in WHC (drip loss varying from 2.8% to 11.3%). Regression analyses revealed correlation coefficients of r=-0.32 (P=0.08) and r=0.40 (P=0.03) for the correlations between the content of integrin determined by western blot analysis and WHC determined as either drip loss or by NMR, respectively. Water mobility and distribution was also measured in 18 meat samples upon 7 days of aging, which revealed a correlation (r=0.54) between integrin content determined by western blot analysis 24h postmortem and the mobility of the myofibrillar water (T(21) relaxation time) at day 7. In contrast, no correlation could be established between integrin content 24h postmortem and WHC at day 7 determined by NMR as the amount of extramyofibrillar water (T(22) population) (r=-0.01). In conclusion, both visualisation by CLSM and quantification of integrin by western blot analyses of suggested that a strong link between integrin degradation and WHC in pork is questionable, whereas integrin degradation seems to have impact on the succeeding development in the mobility of the myofibrillar water.     

How energy efficiency fails in the building industry

This paper examines how energy efficiency fails in the building industry based on many years of research into the integration of energy efficiency in the construction of buildings and sustainable architecture in Norway. It argues that energy-efficient construction has been seriously restrained by three interrelated problems: (1) deficiencies in public policy to stimulate energy efficiency, (2) limited governmental efforts to regulate the building industry, and (3) a conservative building industry. The paper concludes that innovation and implementation of new, energy-efficient technologies in the building industry requires new policies, better regulations and reformed practices in the industry itself.     

Aging-induced changes in microstructure and water distribution in fresh and cooked pork in relation to water-holding capacity and cooking loss - A combined confocal laser scanning microscopy (CLSM) and low-field nuclear magnetic resonance relaxation study

Confocal laser scanning microscopy (CLSM) and low-field nuclear magnetic resonance (LF-NMR) relaxometry were combined to characterize microstructural changes and water distribution in fresh and cooked pork during an aging period of 14 days. At day 1 (24 h postmortem) a few muscle fibres, which appear swollen, were observed in both fresh and cooked meat. An identical microstructure was still apparent after 14 days, however, the number of muscle fibres showing distinguished characteristics was found to increase throughout the aging period. Hence, it was apparent that during aging the individual fibres swell and disintegrate at different rates. Development in water-holding capacity (WHC) was followed during the aging period using gravimetric methods, and an increase in the WHC in the fresh meat was observed, which resembled the amount of extramyofibrillar water measured by NMR relaxometry (T₂₂ population). This was consistent with the CLSM images, as a substantial increase in the number of myofibrils that appeared swollen, capable of holding more water, was observed during aging. In the cooked meat the width of the T_21c population, reflecting the myofibrillar water in the cooked meat, was seen to decrease during the entire storage period, which corresponds to the development of a more homogeneous structure. In the CLSM data a continuous degradation during the storage period was observed, which could resemble a shift to a more homogeneous structure. Comparison of CLSM of transverse sections of fresh and cooked pork revealed a pronounced shrinkage of muscle fibres upon cooking. This resulted in large gaps between the cooked muscle fibres, which also was visible as shrinkage at the level of the individual myofibrils. This pattern was also reflected in the NMR relaxation data. The cooking-induced shrinkage of the myofibrils occurred concomitantly with a decrease in the amount of intermyofibrillar water within the individual fibre and an increase in the larger extramyofibrillar spaces between fibres, i.e. water is expelled from the myofibrillar matrix upon cooking. Accordingly, the present study demonstrated that the use of CLSM together with NMR relaxometry can provide further information on the relationship between structural characteristics of meat and resultant water distribution.