13C n.m.r. study of raw materials for carbon black

¹³C n.m.r. spectroscopy has been applied to investigate a number of coal tar and petroleum-derived carbon black feedstocks. Application of the J-modulated spin echo technique is especially rewarding, as this method renders the quaternary carbons directly detectable. Thus the quality of carbon black feedstocks can additionally be gauged on the basis of the contents of quaternary carbons, which is a direct indication of the carbon yield in the carbon black production process.     

Three-dimensional motion capture protocol for seated operator in whole body vibration

A new methodology to measure the response of seated people to whole body vibration (WBV) is presented in this work. The proposed methodology is based on using motion capture systems with reflective markers to detect the position versus time motion of selective landmarks on the human body during vibration while taking into consideration the seatback. The methodology also circumvented the problem of tracking the motion of the physical markers on the lower thoracic and lumbar areas of the spine, which cannot be seen by the cameras due to the existence of the seatback, by introducing virtual (calculated) markers that substitute for the physical markers. Additional (redundant) markers were attached to the segments of interest to generate local coordinate systems that can be used to obtain the trajectories of the virtual markers. Simulated ride files containing both complex vibration and mild impact signals were played back through a man-rated 6 d.f. motion platform. The methodology was tested on three seated subjects; there was considerable agreement between the trajectories of the physical and virtual markers. Error assessments also showed insignificant discrepancy between the physical and virtual markers. The proposed methodology showed encouraging results in WBV testing and may be useful for other applications where people perform tasks in a seated position.

Relevance to industry

People who operate heavy construction machinery can be at increased risk for low back pain and other musculoskeletal problems. WBV in combination with postural constraints is one potential underlying cause for these complaints. However, WBV is difficult to study without altering the typical operator environment as the seatback and armrests often limit the ability to monitor human motion, particularly the lumbar spine. The development of an efficient and effective technique for measuring three-dimensional (3D) displacement data of the lower back region of seated operators in realistic environments exposed to WBV, could advance the development and validation process of computer human modeling in this field. Preventing these problems can save people significant suffering and industry significant cost due to compensation, medical care, lost productivity, and retraining.     

Multichannel, Single Tral Event Related Potential Classification

We report on the effect of electrode placement and number of electrodes on the classification of single trial event related potentials (ERP's). The subjects read propositions relating fictitious people and their occupations while ERP's were recorded. The subjects decided if the proposition was correct or incorrect and responded as per instructions. The single trial, multichannel ERP data were classified using various methods, e. g., hold-out, leave-one-out, resubstitution. Several other factors were examined to determine their effect on ERP classification, including taking a majority vote among channels, using the single best channel, and averaging the data across channels for a single ERP. The results from other experiments are compared to those presented here.     

Some determinants of the persuasive power of in-groups and out-groups: Organization of information and attribution of independence.

Four experiments examined the hypothesis that in-groups exert more influence than do out-groups. The hypothesis was supported using both laboratory groups of university students and a natural social category (university affiliation). Ss exposed to in-group communicators attributed greater independence to them, made fewer errors in recalling their messages, and clustered recollections of messages by individual speaker. In addition, the persuasiveness of out-group members was enhanced when individuating information was provided about them that increased their heterogeneity. The individuated out-group members were as influential as in-group communicators. Results were interpreted in terms of attribution and social identity processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

In vitro dissolution of two oral controlled release preparations of diclofenac sodium.

The development of controlled release formulations has brought about the need for appropriate quality control methods such as in vitro dissolution testing. Such tests are principally designed to obtain correlation with the in vivo performance of the formulation (1,2,3). If an in vitro test can be defined offering a good correlation the test may serve for routine quality control or may be useful in screening new drug formulations.     

Psychometric properties of the Geriatric Depression Scale among the institutionalized aged.

Validity and reliability of the Geriatric Depression Scale (GDS) were examined among 806 nursing home and congregate apartment residents (mean age 84 years). The scale was highly internally consistent and, although a clean factor structure emerged, basically unidimensional. Test-retest reliability at 1 mo was good, but correlations with staff-rated depression were only moderate. GDS-based classifications of respondents as suffering possible major, minor, or no depression were fairly consistent with those based on a symptom checklist and with clinical diagnoses. However, both the GDS and the checklist yielded high false negative rates vis à vis clinically diagnosed minor depression. There were no differences in reliability or validity for cognitively impaired and intact groups. GDS responses did not vary with age or length of institutionalization, but there was a positive correlation with functional disability and ill health. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Summoning earth and fire: The energy development implications of Grameen Shakti (GS) in Bangladesh

Since its establishment in 1996, the nonprofit company Grameen Shakti (GS) has installed almost half a million solar home systems (SHS), 132,000 cookstoves, and 13,300 biogas plants among 3.1 million beneficiaries. They plan to ramp up their expansion so that by 2015, more than 1.5 million SHS are in place along with 100,000 biogas units and 5 million improved cookstoves. This article describes GS’s current activities, the contours of its programs, and likely reasons for its success. It also explores the remaining challenges facing GS and distils common lessons for other energy development assistance projects and programs around the world. After detailing research methods consisting primarily of research interviews and site visits, the article briefly explores the history of GS and summarizes its three most prominent programs. The article then identifies six distinct benefits to their programs—expansion of energy access, less deforestation and fewer greenhouse gas emissions, price savings, direct employment and income generation, improved public health, and better technology—before discussing challenges related to staff retention and organizational growth, living standards, technical obstacles, affordability, tension with other energy programs, political constraints, and awareness and cultural values.     

Of critical importance: Toward a quantitative probabilistic risk assessment framework for critical infrastructure

Critical comments can be made to the current risk assessment framework for critical infrastructure used in The Netherlands: the Dutch National Risk Assessment (DNRA). The DNRA uses a qualitative approach to risk assessment, based on, for example, ordinal risk scoring and the risk matrix. Even though qualitative risk assessment methods are internationally popular, there is no scientific evidence that a qualitative approach to risk assessment actually works. In the case of the DNRA, the main points of criticisms relate to the usage of a subjective concept of risk, dependency on subjective risk experts, the use of risk matrices and the absence of decision rules. To combat these criticisms, this article proposes a quantitative probabilistic risk assessment framework for critical infrastructure based upon four design principles, that a methodologically justified risk assessment method for critical infrastructure should meet. The proposal made for the quantitative risk assessment framework uses a Bayesian approach, a standardized measure for negligible risk in the form of a yearly mortality probability of 10⁻⁶, and Disability Adjusted Life Years to quantify human life years for social cost–benefit analysis. Finally, the proposed quantitative method is demonstrated in a case study.     

Thermal Analysis and Cone Calorimeter Study of Engineered Wood with an Emphasis on Fire Modelling

Fire Technology - Engineered wood products (EWPs) are a group of materials having a very similar chemical composition but having different and non-uniform thermo-physical properties throughout...