Mechanical properties with respect to water content of gelatin films in glassy state

Changes on the structural and molecular level of gelatin films induced by hydration below 25±3% water content (glass–rubbery transition at ambient temperature) were identified with DSC and FTIR spectroscopy. Three main stages of hydration were distinguished: (I) water bound by high-energy sorption centres; (II) structural water; (III) polymolecular layer water. The mechanical behaviour of gelatin films at each stage of hydration was characterized. Relaxation of the films during hydration was taken into account in the analysis of results. Hydrated gelatin films were characterized as brittle below the glass–rubbery transition at ambient temperature, however some improvement of mechanical properties related to a higher renaturation level was showed between 7 and 14% of water content in stage II (structural water).     

Sex pheromone of fall armyworm,Spodoptera frugiperda (J.E. Smith)

Analyses of extracts of pheromone glands and of volatiles from calling female fall armyworm moths,Spodoptera frugiperda (J.E. Smith), revealed the presence of the following compounds: dodecan-1-ol acetate, (Z)-7-dodecen-1-ol acetate, 11-dodecen-1-ol acetate, (Z)-9-tetradecenal, (Z)-9-tetradecen-1-ol acetate, (Z)-11-hexadecenal, and (Z)-11-hexadecen-1-ol acetate. The volatiles emitted by calling females differed from the gland extract in that the two aldehydes were absent. Field tests were conducted with sticky traps baited with rubber septa formulated to release blends with the same component ratios as those emitted by calling females. These tests demonstrated that both (Z)-7-dodecen-1-ol acetate and (Z)-9-tetradecen-1-ol acetate are required for optimum activity and that this blend is a significantly better lure than either virgin females or 25 mg of (Z)-9-dodecen-1-ol acetate in a polyethylene vial, the previously used standard. Addition of the other three acetates found in the volatiles did not significantly increase the effectiveness of the two-component blend as a bait for Pherocon 1C or International Pheromones moth traps.Mention of a commercial or proprietary product does not constitute an endorsement by the USDA.     

Structure and biosynthesis of novel conjugated polyene fatty acids from the marine green algaAnadyomene stellata

Novel polyunsaturated fatty acids with four conjugated double bonds were found in extracts of the green macroalga,Anadyomene stellata. The isolation of five of these with different chain lengths and varying degrees of unsaturation −16∶5, 18∶4, 20∶5, 20∶6, and 22∶7—was accomplished by organic extraction followed by a combination of vaccum and high-performarce liquid chromatography. One of these that was a novel substance (22∶7) was characterized as 4ZZ,7Z,9E,13Z,16Z,19Z-docosaheptaenoic acid and assigned the trivial name stellaheptaenoic acid. The structure of this new compound, isolated as its methyl ester derivative, was deduced from detailed nuclear magnetic resonance, gas chromatography/mass spectrometry (GC/MS), and other spectroscopic methods. Incubation of a chloroplast preparation, isolated from a crude algal homogenate by differential centrifugation, with six unsaturated fatty acids (palmitoleic, 6Z,9Z,12Z,15Z-octadecatetraenoic acid, arachidonic acid, eicosapentaenoic acid, 7Z,10Z,13Z,16Z-docosatetraenoic acid, and 4Z,7Z,10Z,13Z,16Z,19Z-docosahexaenoic acid) resulted in substantially increased synthesis of unique tetraene compouds as detected by ultraviolet spectrophotometry and tentatively identified by GC/MS.     

Effect of Neutron Irradiation on Knoop Microhardness Anisotropy in MgO·3Al2O3 Single Crystals

MgO·3Al₂O₃ single crystals were irradiated with neutron fluences of 8.3 × 10²² n/m² at 100°C and 2.4 × 10²⁴ n/m² at 470°C ( E > 1.0 MeV) in the Japan Materials Testing Reactor. The Knoop microhardness of several orientations on the (100) plane of both the irradiated and unirradiated crystals were measured with different indentation loads. The change in hardness profile of the crystals was almost the same after the two irradiation conditions. The hardness increased by 4–15% because of the irradiations depending on the crystallographic orientation, the larger change being observed at orientations between the (001) and (011) directions. While both the {111}     and {110}     slip systems are simultaneously active in the unirradiated MgO·3Al₂O₃, the {111}     system may be the dominant slip system in the neutron-irradiated crystals. It is concluded that the restriction of the {110}     slip system is caused by irradiation-induced interstitial ions.     

A study on estimation of early discharge day for home health care and medical expense for inpatients

This report was done mid way through the study "A Demonstration-Cum-Research on the Reimbursement system and cost-effectiveness of Home Health Care Program in Korea". It focused on developing an estimation of early discharge day to home health care based on analysis medical records and on an analysis of medical expenses based on a detailed statement of treatment for inpatients who were hospitalized at S General Hospital in 1991. Two research methods were adopted for estimation of the early discharge day. One was micro-analysis from the medical records and the other was macro-analysis to clarify the estimated early discharge day to home health care for patients with four diseases judged from need assessment to be candidates for this type of program, namely patients with, Cesarean Section, Hypertension, Diabetes Mellitus, Chronic Obstructive Pulmonary Disease (COPD). Estimation of early discharge day to home health care were developed through many aspects of analysis of the signs and symptoms by disease in a micro-analysis in addition to a decrease in the amount of treatment, drugs, tests and changes in the test consistency, drug methods, and client's condition in the macro-analysis. Accordingly, an early discharge day for inpatients was finally estimated through the analysis of the client's conditions and treatment, drugs, tests, and nursing care activities that the patient received during hospitalization. From the research findings, the following summarized conclusions have drawn. First, for patients with Cesarean Sections, after assessing each items using the two analysis methods, the mean period of hospitalization was 8.8 days, but the mean period of hospitalization was estimated at 4.1 days if early discharge to home health care could be done. Second, for patients with Hypertension, the same method as for the patients with the Cesarean Sections was used and the result was reduction from a mean period of the hospitalization of 9.9 days to a mean period of the hospitalization of 5.2 days. Third, for patients with Diabetes Mellitus there was a decrease from a mean period of the hospitalization of 11.7 days to a mean period of hospitalization of 8.4 days if early discharge to home health care could be done. Fourth, for patients with Chronic Obstructive Pulmonary Disease, the mean period of the hospitalization was 14.3 days, but the mean period of the hospitalization could be 8.1 days if early discharge to home health care could be done.(ABSTRACT TRUNCATED AT 400 WORDS)     

Ubiquitous Access to Unified Messaging: A Study of Usability and the Use of Pervasive Computing

The advent of mobile devices and the wireless Internet is having a profound impact on the way people communicate, as well as on the user interaction paradigms used to access information that was traditionally accessible only through visual interfaces. Applications for mobile devices entail the integration of various data sources optimized for delivery to limited hardware resources and intermittently connected devices through wireless networks. Although telephone interfaces arise as one of the most prominent pervasive applications, they present interaction challenges such as the augmentation of speech recognition through natural language (NL) understanding and high-quality text-to-speech conversion. This article presents an experience in building an automated assistant that is natural to use and could become an alternative to a human assistant. The Mobile Assistant (MA) can read e-mail messages, book appointments, take phone messages, and provide access to personal-organizer information. Key components are a conversational interface, enterprise integration, and notifications tailored to user preferences. The focus of the research has been on supporting the pressing communication needs of mobile workers and overcoming technological hurdles such as achieving high accuracy speech recognition in noisy environments, NL understanding, and optimal message presentation on a variety of devices and modalities. The article outlines findings from the 2 broad field trials and lessons learned regarding the support of mobile workers with pervasive computing devices and emerging technologies.     

Rebalancing an investment portfolio in the presence of convex transaction costs,including market impact costs

The inclusion of transaction costs is an essential element of any realistic portfolio optimization. We extend the standard portfolio optimization problem to consider convex transaction costs incurred when rebalancing an investment portfolio. Market impact costs measure the effect on the price of a security that result from an effort to buy or sell the security, and they can constitute a large part of the total transaction costs. The loss to a portfolio from market impact costs is often modelled with a convex function that can be expressed using second-order cone constraints. The Markowitz framework of mean-variance efficiency is used. In order to properly represent the variance of the resulting portfolio, we suggest rescaling by the funds available after paying the transaction costs. This results in a fractional programming problem, which we show can be reformulated as an equivalent convex program of size comparable to the model without transaction costs. We show that an optimal solution to the convex program can always be found that does not discard assets.     

Fracture mechanics analysis of the dentine-luting cement interface

The objectives of this study were to determine the fracture toughness of adhesive interfaces between dentine and clinically relevant, thin layers of dental luting cements. Cements tested included a conventional glass-ionomer, F (Fuji 1), a resin-modified glass-ionomer, FP (Fuji Plus) and a compomer cement, D (DyractCem). Ten miniature short-bar chevron notch specimens were manufactured for each cement, each comprising a 40 microm thick chevron of lute, between two 1.5 mm thick blocks of bovine dentine, encased in resin composite. The interfacial K(IC) results (MN/m3/2) were median (range): F; 0.152 (0.14-0.16), FP; 0.306 (0.27-0.37), D; 0.351 (0.31-0.37). Non-parametric statistical analysis showed that the fracture toughness of F was significantly lower (p <0.05) than those of FP or D, and all were significantly lower than values for monolithic cement specimens. Scanning electron microscopy of the specimens suggested crack propagation along the interface. However, energy dispersive X-ray analysis indicated that failure was cohesive within the cement. It is concluded that the fracture toughness of luting cement was lowered by cement-dentine interactions.     

Direct modulation of the effective sensitivity of a CCD detector: a new approach to time-resolved fluorescence imaging

In this paper a novel approach to frequency‐domain fluorescence lifetime imaging (FLIM) is described. In a CCD camera a single pixel is defined by a charge pattern on a group of electrodes. By modulation of the pattern of voltages defining the pixel structure it is possible to modulate the sensitivity of the CCD at radio frequency. The modulation enhances the noise performance of the CCD, in contrast to the deterioration in performance seen when an intensifier stage is similarly modulated. The new technology has potential applications to a wide range of assays as well as in conventional FLIM applications. Unlike intensifier‐based systems, the directly modulated CCD is physically small, inexpensive, robust and offers superior resolution and noise performance.