HOUSING SEGREGATION IN THE SCHOOL AGE POPULATION AND THE LINK BETWEEN HOUSING AND SCHOOL SEGREGATION: A ST. LOUIS CASE STUDY

The age distributions of the black and white populations vary, as do the ways in which blacks and whites of differing ages are distributed geographically in metropolitan areas. The nature of these differences is such that, in racially mixed neighborhoods, black families with children are often mixed with childless or elderly white adults. For this reason, it is hypothesized that the school-age (5 to 17 years of age) population is more residentially segregated by race than is the total population. To test this hypothesis, segregation indices based on census tract data were computed for the St. Louis SMSA for 1980, for the total population and the school-age population. This analysis confirmed that the school-age population was somewhat more segregated than the total population. The implications of this finding for the problem of school segregation are discussed, as is the interrelationship between housing segregation and school segregation.     

A high-speed, low-power divide-by-4 frequency divider implementedwith AlInAs/GaInAs HBT's

The authors describe the first frequency divider demonstrated using AlInAs/GaInAs heterojunction bipolar transistors (HBTs). The divider (a static 1/4 divider circuit) operates up to a maximum frequency of 17.1 GHz, corresponding to a gate delay of 29 ps for a bilevel current-mode logic (CML) gate with a fan-out of 2, and a total power consumption of 67 mW (about 4.5 mW per equivalent NOR gate). These results demonstrate the potential of AlInAs/GaInAs HBTs for implementing low-power, high-speed integrated circuits     

An attack-norm separation approach for detecting cyber attacks

The two existing approaches to detecting cyber attacks on computers and networks, signature recognition and anomaly detection, have shortcomings related to the accuracy and efficiency of detection. This paper describes a new approach to cyber attack (intrusion) detection that aims to overcome these shortcomings through several innovations. We call our approach attack-norm separation. The attack-norm separation approach engages in the scientific discovery of data, features and characteristics for cyber signal (attack data) and noise (normal data). We use attack profiling and analytical discovery techniques to generalize the data, features and characteristics that exist in cyber attack and norm data. We also leverage well-established signal detection models in the physical space (e.g., radar signal detection), and verify them in the cyberspace. With this foundation of information, we build attack-norm separation models that incorporate both attack and norm characteristics. This enables us to take the least amount of relevant data necessary to achieve detection accuracy and efficiency. The attack-norm separation approach considers not only activity data, but also state and performance data along the cause-effect chains of cyber attacks on computers and networks. This enables us to achieve some detection adequacy lacking in existing intrusion detection systems. Nong Ye is a Professor of Industrial Engineering and an Affiliated Professor of Computer Science and Engineering at Arizona State University (ASU) the Director of the Information Systems Assurance Laboratory at ASU. Her research interests lie in security and Quality of Service assurance of information systems and infrastructures. She holds a Ph.D. degree in Industrial Engineering from Purdue University, West Lafayette, and M.S. and B.S. degrees in Computer Science from the Chinese Academy of Sciences and Peking University in China respectively. She is a senior member of IIE and IEEE, and an Associate Editor for IEEE Transactions on Systems, Man, and Cybernetics and IEEE Transactions on Reliability. Toni Farley is the Assistant Director of the Information and Systems Assurance Laboratory, and a doctoral student of Computer Science at Arizona State University (ASU), Tempe, Arizona. She is studying under a Graduate Fellowship from AT&T Labs-Research. Her research interests include graphs, networks and network security. She holds a B.S. degree in Computer Science and Engineering from ASU. She is a member of IEEE and the IEEE Computer Society. Her email address is toni@asu.edu. Deepak Lakshminarasimhan is a Research Assistant at the Information and Systems Assurance Laboratory, and a Master of Science student of Electrical engineering at Arizona State University (ASU), Tempe, Arizona. His research interests include network security, digital signal processing and statistical data analysis. He holds a B.S degree in Electronics and Communication Engineering from Bharathidasan University in India.     

A general method for functionalisation of microgel particles with primary amines using click chemistry

In this study we introduce a general method for functionalising microgel particles with primary amine groups using a one-step copper catalysed azide-alkyne cycloaddition (CuAAC) reaction. Three different families of microgels containing copolymerised propargyl acrylate (PA) were prepared and then reacted with 2-azido-1-ethylamine (AEA) using CuAAC. The microgels contained poly(ethyl acrylate) (PEA), poly(2-vinylpyridine) (PVP) or poly(N-isopropylacrylamide) (PNP). The functionalisation of the microgels containing PA (i.e., PX-PA) by AEA to give primary amine functionalised particles (PX-PA-AEA) was assessed by elemental analysis and FTIR. The reaction of AEA with PA was quantitative for each of the PX-PA-AEA microgels (X = EA, VP and NP). The PX-PA-AEA systems generally showed larger pH-triggered swelling and zeta potentials than the non-clicked PX-PA particles. The results also showed that PA restricted swelling of the PX-PA and PX-PA-AEA particles by acting as a crosslinker. Of the three microgel systems studied, PVP-PA-AEA had the best combination of high AEA incorporation and pH-triggered swelling.     

Iron(II)-catalyzed oxidation of arsenic(III) in a sediment column

Arsenic contamination in aquatic systems is a worldwide concern. Understanding the redox cycling of arsenic in sediments is critical in evaluating the fate of arsenic in aquatic environments and in developing sediment quality guidelines. The direct oxidation of inorganic trivalent arsenic, As(III), by dissolved molecular oxygen has been studied and found to be quite slow. A chemical pathway for As(III) oxidation has been proposed recently in which a radical species, Fe(IV), produced during the oxidation of divalent iron, Fe(II), facilitates the oxidation of As(III). Rapid oxidation of As(III) was observed (on a time scale of hours) in batch systems at pH 7 and 7.5, but the extent of As(III) oxidation was limited. The Fe(II)-catalyzed oxidation of As(III) is examined in a sediment column using both computational and experimental studies. A reactive-transport model is constructed that incorporates the complex kinetics of radical species generation and Fe(II) and As(III) oxidation that have been developed previously. The model is applied to experimental column data. Results indicate that the proposed chemical pathway can explain As(III) oxidation in sediments and that transport in sediments plays a vital role in increasing the extent of As(III) oxidation and efficiency of the Fe(II) catalysis.     

The impact of the Occupational Choice Strategy on the career development of rehabilitation clients.

Examination of the impact of an occupational choice strategy (OCS) on the career development of clients in a comprehensive rehabilitation center indicates that the 20 participants (aged 17–53 yrs) in OCS scored consistently higher than did the 20 control Ss on career decidedness, vocational identity, vocational self-awareness, vocational knowledge, and readiness for vocational planning. OCS Ss were also more likely than controls to persist in their rehabilitation programs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

University productivity rankings: A psychologist by any other name.

Refuted W. M. Cox and V. Catt's (see record 1978-21651-001) findings on productivity ratings of graduate psychology programs based on publication in American Psychological journals. Records from the University of Wisconsin—Madison (UW) for authors whose departmental affiliations were not specified in the various journals were examined. Instead of 8.6%, 40% of the articles associated with UW came from nonpsychology departments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)