The Reed-Solomon encoders: Conventional versus Berlekamp's architecture

Concatenated coding was adopted for interplanetary space missions. Concatenated coding was employed with a convolutional inner code and a Reed-Solomon (RS) outer code for spacecraft telemetry. Conventional RS encoders are compared with those that incorporate two architectural features which approximately halve the number of multiplications of a set of fixed arguments by any RS codeword symbol. The fixed arguments and the RS symbols are taken from a nonbinary finite field. Each set of multiplications is bit-serially performed and completed during one (bit-serial) symbol shift. All firmware employed by conventional RS encoders is eliminated

System for generating timing and control signals

A system capable of generating every possible data frame subperiod and delayed subperiod of a data frame of length of M clock pulse intervals (CPIs) comprised of parallel modulo-m sub i counters is presented. Each m sub i is a prime power divisor of M and a cascade of alpha sub i identical modulo-p sub i counters. The modulo-p sub i counters are feedback shift registers which cycle through p sub i distinct states. Every possible nontrivial data frame subperiod and delayed subperiod is derived and a specific CPI in the data frame is detected. The number of clock pulses required to bring every modulo-p sub i counter to a respective designated state or count is determined by the Chinese remainder theorem. This corresponds to the solution of simultaneous congruences over relatively prime moduli

Propionibacterium acnes infections in patients with idiopathic scoliosis: a case-control study and review of the literature.

Purpose:Surgical site infection (SSI) caused by Propionibacterium acnes is an infrequent but devastating complication after spinal fusion. The purpose of this study was to identify risk factors for SSI with Propionibacterium acnes after spinal fusion for juvenile and adolescent idiopathic scoliosis (JIS and AIS). Methods:A case-control study was performed. Each case was matched 2:1 for age, gender and diagnosis. Retrospective chart review was performed to obtain relevant demographic, surgical and clinical data for all cases and controls. Statistical analysis included paired t-test and McNemar test, as well as exact logistic regression and robust regression models. Results:This study included ten infection cases (eight AIS, two JIS) and 20 controls (16 AIS, four JIS). In total, six infected cases presented within two weeks of the index procedure (acute infection) and four infected cases presented more than one year from the index procedure (delayed infection). The most common presentation for acute infections was wound drainage, while back pain was more common in delayed infections. All infections were successfully treated with surgical irrigation and debridement and postoperative antibiotics. Hardware was removed for patients with delayed infections. The strongest risk factor for infection was increased requirement for blood transfusion, but it did not reach statistical significance. Conclusion:SSI with Propionibacterium acnes is an important complication after spinal fusion for idiopathic scoliosis. These infections can be successfully treated, but larger studies are needed to further identify risk factors and establish standardized guidelines for the treatment and prevention of this complication. Level of Evidence Level III

Southeast Asian Refugee-Learners: Identities Informing ESL Education and Support

Serving as a synthesis of previously published studies and digests, this paper focuses on Southeast Asian refugees in America to address the complex interaction between refugee-learners’ ongoing construction of identity and the ESL environment. Drawing on a wealth of historical and contemporary research on one of America’s most prominent refugee populations, this exploration highlights the traits that constitute Southeast Asians as a unique group of learners due to their shared histories of trauma; social, cultural and religious influences; and ongoing sociocultural and linguistic negotiations of identity during resettlement. As a result, ESL programs and practitioners become critical to both language acquisition and sociocultural support of both Southeast Asian and other refugee-learners. Reflecting this dynamic nature of the learner-program relationship, this paper also offers curriculum- and teacher-specific suggestions for engaging and empowering both Southeast Asians and other refugee populations through ESL instruction. The goal of this survey is to raise awareness of refugee-learner identity and second language acquisition as a means of promoting further dialogue among ESL practitioners

The Teacher CARE project: Enhancing motivation, engagement and effort of a-motivated students

The purpose of this study was to examine the influence of different relatedness supportive settings on the motivation, engagement and effort of a-motivated students in secondary physical education. 147 a-motivated students from 5 schools were taught in a setting that was either high or low in support for their need of relatedness. Data were collected using a pretest and posttest design to examine a-motivated student\u27s level of motivation, engagement and effort. Repeated measures ANOVA\u27s with follow-up comparisons were utilized to analyze the data. Results indicated that students engaged in the high supportive setting significantly increased their levels of motivation, engagement and effort compared with students in the low support group. Findings from this study provide the first empirical evidence that supporting relatedness can positively influence the affective aspects of students with low motivation

A study of self-determined motivation toward physical education among different levels of schooling

Educational research is continously examining the changes and progress of students throughout their educational career. Understanding student change is a critical element in creating learning settings that can meet the diverse needs of students. An area of inquiry important to the education, engagement and learning of students is their motivation or self-determination. Researchers commonly make an inference that motivation decreases as student\u27s progress throughout their academic career, yet no empirical evidence has been gathered to support these claims. Therefore, the purpose of this study was to examine the self-determined motivation toward physical education of three different groups of students. Data were collected using a cross-sectional longitudinal design, whereby 50 students each in grades 7, 9 and 11 were randomly selected for this study and completed a survey on motivation toward physical education. Results revealed that as students progressed throughout their career, their motivation toward physical education decreased

The Utility of Trouble: Maximizing the Value of Our Human Services Dollars

Outlines recommendations to standardize service delivery areas and consolidate area offices of the state's seven largest human services agencies, as well as to close antiquated institutions. Projects benefits such as improved accessibility and savings

A new culture method for biochemical studies of the circadian clock

A new culture method for biochemical studies of the circadian cloc

The HI Environment of Nearby Lyman-alpha Absorbers

We present the results of a VLA and WSRT search for HI emission from the vicinity of seven nearby clouds, which were observed in Lya absorption with HST toward Mrk335, Mrk501 and PKS2155-304. We searched a volume of 40' x 40' x 1000 km/s. The HI mass sensitivity (5 sigma) varies from 5x10^6 to 5x10^8 Msun. We detected HI emission in the vicinity of four out of seven absorbers. The closest galaxy is a small dwarf galaxy at a projected distance of 68/h kpc from the sight line toward Mrk335. It has the same velocity (V=1970 km/s) as one of the absorbers, and has an HI mass of only 4x10^7 Msun. We found a more luminous galaxy at the velocity (V=5100 km/s) of one of the absorbers toward PKS2155-304, 230/h kpc from the sight line. Two other, stronger absorbers toward PKS2155-304 at V=17,000 km/s are associated with a loose group of three bright spiral galaxies, at projected distances of 300 to 600/h kpc. These results support the conclusion that most nearby Lya forest clouds trace the large-scale structures outlined by optically luminous galaxies. We do not find any evidence for a physical association between an absorber and its closest galaxy.Comment: 4 Tables, 11 Figures, to be published in Astron J. (Oct 1996) Vol 11