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1.
Methods for assaying lysosomal diseases in dried blood samples are very useful today due to its several advantages related to the stability of samples, its transportation, handled and analysis, and its potential use for newborn screening compared to traditional methods in leucocytes samples. For this reason, it is important to validate these assays before being used in routine laboratory. Because of different in biological markers based on ethnicity, we aimed this study to validation a DBS-based fluorometric assay for measurement of α-l-Iduronidase activity for diagnosis of MPS I patients in Iran. DBS samples were collected from 15 MPS I patients and 60 healthy age matched subjects. Diagnostic value, biological variance and α-l-Iduronidase activity were determined. DBS α-l-Iduronidase activity was significantly higher in male subjects than in female group. Using a cut-off level of 1.08 µmol/spot 20 h, sensitivity and specificity were 100 and 98 %. The linearity of test was proved and we showed that within-run and between run precision were 5.6 and 14.66 %. Measurement of α-l-Iduronidase activity in DBS samples is an accurate test for diagnosis of MPS I and because of its rapid shipping and simplicity to keeping, DBS-based enzyme activity could be considered as a useful diagnostic tool in this disease.  相似文献   
2.
Owing to the higher amount and the better quality of power transferred, three-phase multilevel inverters have strengthened their presence in low-power photovoltaic (PV) applications. However, the existing topologies investigated for low-power PV systems are basically meant for medium- and high-power applications, thus making them underutilized for low-power range. In order to address this shortcoming, this paper proposes a three-phase multilevel inverter with a switch-sharing capability and its control solution. It combines the characteristics of the two-level full-bridge topology and the diode-clamped multilevel structure. As a result, the inverter can be used with full capacity and without being underutilized, and significantly improves the output quality. A control strategy that is able to maximize the full potential of the inverter is developed. A digital proportional-integral (PI) controller with a new tuning algorithm is designed to effectively deal with the load changes. The result reveals that the load current is always retained at the intended quality level despite the variations in load. The performance of the inverter is validated from the experimental work conducted on a laboratory prototype under closed-loop conditions.  相似文献   
3.
Charlotte Dietrich, Der Rundfunk in Afrika An fang der Siebziger Jahre: Strukturen and Daten (Broadcasting in Africa in the Early Seventies: Structures and Data) (Department of Mass Communication, University of Salzburg, Sigmund Haffner Gasse 18, A-5020 Salzburg, Austria---$5.00, paper, plus cost of shipping)

Communication Policy and Planning for Development: A Selected Annotated Bibliography by Syed A. Rahim (285 pp., October 1976, price not given, paper)

An Overview of Communication Research in Asia: Status, Problems and Needs by Gloria D. Feliciano (20 pp., June 1973, on request, paper)

Mass Media Use and the “Revolution of Rising Frustrations:” A Reconsideration of the Theory by Robert C. Hornik (27 pp., July 1974, on request, paper)

Communication and Development in China (Communication Monograph No. 1), by Godwin Chu, et al. (116 pp., September 1976, price not given, paper)

Communication in the Pacific, edited by Daniel Lerner and Jim Richstad (96 pp., June 1976, price not given paper)

The Use of Radio in Adult Literacy Education, by Richard C. Burke (116 pp., £1.50 or about $2.40, paper)

Programmed Instruction for Literacy Workers, by Sivasailam Thiagarajan (136 pp., £1.95 or about $3.12, paper)

Mass Communication in Malaysia, compiled by Lim Huck Tee and V.V. Sarachandran (91 pp., 1975, 12 Singapore dollars outside Asia)

Mass Communication in India, compiled at the Indian Institute of Mass Communication (216 pp., 1976, 18 Singapore dollars outside Asia)  相似文献   
4.

Objective

Heavy ion beam, which has emerged as a new mutagen in the mutation breeding of crops and ornamental plants, is expected to result in the induction of novel mutations. This study investigates the morphological and biochemical responses of Oryza sativa toward different doses of carbon ion beam irradiation.

Methods

In this study, the dry seeds of O. sativa were irradiated at 0, 20, 40, 60, 80, 100, and 120 Gy, followed by in-vitro germination under controlled conditions. Morphological and biochemical studies were conducted to investigate the morphological and physiological responses of O. sativa towards ion beam irradiation.

Results

The study demonstrated that low doses (10 Gy) of ion beam have a stimulating effect on the height, root length, and fresh weight of the plantlets but not on the number of leaves. Meanwhile, doses higher than 10 Gy caused reductions in all the morphological parameters studied as compared to the control samples. The highest total soluble protein content [(2.11±0.47) mg/g FW] was observed in plantlets irradiated at 20 Gy. All irradiated plantlets were found to have 0.85% to 58.32% higher specific activity of peroxidase as compared to the control samples. The present study also revealed that low doses of ion beam (10 and 20 Gy) had negligible effect on the total chlorophyll content of O. sativa plantlets while 40 Gy had a stimulating effect on the chlorophyll content. Plantlets irradiated between 40 to 120 Gy were shown to be 0.38% to 9.98% higher in total soluble nitrogen content which, however, was not significantly different from the control samples.

Conclusions

Carbon ion beam irradiation administered at low to moderate doses of 10 to 40 Gy may induce O. sativa mutants with superior characteristics.  相似文献   
5.
This paper deals with the estimation of crest settlement in a concrete face rockfill dam (CFRD), utilizing intelligent methods. Following completion of dam construction, considerable movements of the crest and the body of the dam can develop during the first impoundment of the reservoir. Although there is vast experience worldwide in CFRD design and construction, few accurate experimental relationships are available to predict the settlement in CFRD. The goal is to advance the development of intelligent methods to estimate the subsidence of dams at the design stage. Due to dam zonifieation and uncertainties in material properties, these methods appear to be the appropriate choice. In this study, the crest settlement behavior of CFRDs is analyzed based on compiled data of 24 CFRDs constructed during recent years around the world, along with the utilization of gene ex- pression programming (GEP) and adaptive neuro-fuzzy inference system (ANFIS) methods. In addition, dam height (H), shape factor (St), and time (t, time after first operation) are also assessed, being considered major factors in predicting the settlement behavior. From the relationships proposed, the values ofR2 for both equations of GEP (with and without constant) were 0.9603 and 0.9734, and for the three approaches of ANFIS (grid partitioning (GP), subtractive clustering method (SCM), and fuzzy c-means clustering (FCM)) were 0.9693, 0.8657, and 0.8848, respectively. The obtained results indicate that the overall behavior evaluated by this approach is consistent with the measured data of other CFRDs.  相似文献   
6.
Pseudobranch function has long interested scientists, but its role has yet to be elucidated. Several studies have suggested that pseudobranchs serve respiratory, osmoregulatory, and sensory functions. This work investigated the immunolocalization of pseudobranch carbonic anhydrase (CA) in the teleost fish species rainbow trout (Oncorhynchus mykiss) to clarify its physiological function. CA was purified from rainbow trout gills O. mykiss and specific antibodies were raised. Immunoblotting between tissue homogenates of pseudobranch and gill CA antibodies showed specific immunostaining with only one band corresponding to CA in the pseudobranch homogenate. Results of immunohistochemical technique revealed that CA was distributed within pseudobranch cells and more precisely in the apical parts (anti-vascular) of cells. The basal (vascular) parts of cells, tubular system, blood capillaries, and pillar cells were not immunostained. Immunocytochemistry confirmed these results and showed that some CA enzyme was cytoplasmic and the remainder was linked to membranous structures. The results also showed that the lacunar tissue layers did not display immunoperoxidase activity. Our results indicated that pseudobranch CA may have a function related to the extracellular medium wherein CA intervenes with the mechanism of stimulation of afferent nerve fibers.  相似文献   
7.
Masami Ito, et al. Broadcasting in Japan (London and Boston: Routledge & Kegan Paul, 1978—E4.95/$9.50, paper)

Ibrahim Elsheikh Mass Media and Ideological Change in Egypt (1950-1973) (Amsterdam: University of Amsterdam, 1977—about $40.00, paper)

Mass Media and Cultural Relationships by Anthony Piepe, Sunny Crouch and Miles Emerson (1978, 169 pp.—price not given)

Trade Unionism in Television by Peter Seglow (1978, 287 pp.—price not given)

Cuadernos de Comunicaci(5n (Communication Notes) (Comunicolgia Aplicada de Mexico, S.A. Comunal No. 7, Mexico 20, D.F.—about $55 per year/12 issues).

Godwin C. Chu, Syed A. Rahim, and D. Lawrence Kincaid Institutional Exploration in Communication Technology (Honolulu: East West Communication Institute, East-West Center, 1978 —$3.00, paper)

P. Gould and J. Johnson, An Experiment in the Classification of Television Programs, October 1978, $3.00, paper), and the paper written for laymen, #5 (P. Gould, How Should We Classify Television Programs? October 1978, $2.50, paper)

Journalism Training: An Interim Report by Robert Amerson and John Herbst (30 pp. $1.75)

An Analysis of Ten International Radio News Broadcasts in English to Africa by Douglas A. Boyd and Donald R. MacKay (16 pp., $1.25)

A Look at the World's Radio News by Bert Cowlan and Lee M. Love (39 pp., $2.25)

Education for Communication Development: The Global View by Robert Lindsay (27 pp., $1.75)

A Brief Study on News Patterns in 16 Third World Countries by Edward T. Pinch (15 pp., $1.25)

International Telecommunications and the Requirements of News Services by Ithiel de Sole Pool and Stephen Dizard (19 pp., $1.25)

Foreign News in Nine Arab Countries by Gehan Rachty (21 pp., $1.25)

International News Wires and Third World News in Asia by Wilbur Schramm, et al. (79 pp., $4.00)

The Multinational News Pool by Roger Tatarian (19 pp., $1.25)

International Conferences: Process and Effects by Rosemarie Rogers, et al. (March 1978, 53 pp., $3.00)

Hemisphere Communications in Historical Perspective by James Nelson Goodsell (September 1978, 18 pp., $1.25)

Kaarle Nordenstreng and Herbert I. Schiller, eds. National Sovereignty and International Communication (Norwood, N.J.: Ablex Publishing Corp., 1979—$21.50)

Rosemary Righter's Whose News? Politics, the Press and the Third World (London: Andre Deutsch/New York: Times Books, 1978—$12.50)

Frank Barton The Press of Africa: Persecution & Perseverance (New York: Holmes & Meier/Africana Publishing Co, 1979—$29.50)

Godwin C. Chu, ed. Popular Media in China: Shaping New Cultural Patterns (Honolulu: University Press of Hawaii, 1978—$12.00)  相似文献   
8.
9.
Despite considerable research in advanced countries on public perceptions of and attitudes to modern biotechnology, limited effort has been geared towards developing a structural model of public attitudes to modern biotechnology. The purpose of this paper is to identify the relevant factors influencing public attitudes towards genetically modified (GM) soybean, and to analyze the relationship between all the attitudinal factors. A survey was carried out on 1,017 respondents from various stakeholder groups in the Klang Valley region. Results of the survey have confirmed that attitudes towards complex issues such as biotechnology should be seen as a multifaceted process. The most important factors predicting support for GM soybean are the specific application-linked perceptions about the benefits, acceptance of risk and moral concern while risk and familiarity are significant predictors of benefit and risk acceptance. Attitudes towards GM soybean are also predicted by several general classes of attitude.  相似文献   
10.
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