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Least Number (least + number)
Selected AbstractsMotor stereotypies in children with autism and other developmental disordersDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 1 2009SYLVIE GOLDMAN PHD The purpose of the study was to count and characterize the range of stereotypies , repetitive rhythmical, apparently purposeless movements , in developmentally impaired children with and without autism, and to determine whether some types are more prevalent and diagnostically useful in children with autism. We described each motor stereotypy recorded during 15 minutes of archived videos of standardized play sessions in 277 children (209 males, 68 females; mean age 4y 6mo [SD 1y 5mo], range 2y 11mo,8y 1mo), 129 with autistic disorder (DSM-III-R), and 148 cognitively-matched non-autistic developmentally disordered (NADD) comparison children divided into developmental language disorder and non-autism, low IQ (NALIQ) sub-groups. The parts of the body involved and characteristics of all stereotypies were scored blind to diagnosis. More children with autism had stereotypies than the NADD comparison children. Autism and, to a lesser degree, nonverbal IQ (NVIQ) <80, especially in females contributed independently to the occurrence, number, and variety of stereotypies, with non-autistic children without cognitive impairment having the least number of stereotypies and children with autism and low NVIQ the most. Autism contributed independently to gait and hand/finger stereotypies and NVIQ <80 to head/trunk stereotypies. Atypical gazing at fingers and objects was rare but virtually limited to autism. Stereotypies are environmentally modulated movement disorders, some highly suggestive, but not pathognomonic, of autism. Their underlying brain basis and genetic correlates need investigation. [source] Hybrid kernel learning via genetic optimization for TS fuzzy system identificationINTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING, Issue 1 2010Wei Li Abstract This paper presents a new TS fuzzy system identification approach based on hybrid kernel learning and an improved genetic algorithm (GA). Structure identification is achieved by using support vector regression (SVR), in which a hybrid kernel function is adopted to improve regression performance. For multiple-parameter selection of SVR, the proposed GA is adopted to speed up the search process and guarantee the least number of support vectors. As a result, a concise model structure can be determined by these obtained support vectors. Then, the premise parameters of fuzzy rules can be extracted from results of SVR, and the consequent parameters can be optimized by the least-square method. Simulation results show that the resulting fuzzy model not only achieves satisfactory accuracy, but also takes on good generalization capability. Copyright © 2008 John Wiley & Sons, Ltd. [source] Enantioselective Alcoholysis of meso -Glutaric Anhydrides Catalyzed by Cinchona -Based Sulfonamide CatalystsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 13 2010Sang Eun Park Abstract The bifunctional Cinchona -based sulfonamide catalysts showed the highest levels of enantioselectivity reported to date in the alcoholytic desymmetrization of meso -glutaric anhydrides. Density functional theory (DFT) computational studies provide detailed insight into the observed sense of enantioselectivity. Moreover, detailed experimental studies and single crystal X-ray analysis confirmed that these bifunctional organocatalysts 3 do not form H-bonded self-aggregates in both solution and solid state. The synthetic utility of this methodology was also demonstrated in the synthesis of pharmaceutically important ,-amino acids, such as (S)-pregabalin. Of the many asymmetric syntheses of enantiomerically pure (S)-pregabalin reported to date, our synthesis requires the least number of and the simplest steps. [source] A review of pharmaceutical scheduling processes in six countries and the effect on consumer access to medicinesINTERNATIONAL JOURNAL OF PHARMACY PRACTICE, Issue 2 2006Andrew Gilbert Director, Professor Objective This analysis determined and compared pharmaceutical scheduling arrangements in six selected countries and explored how these different scheduling arrangements affect the availability of medicines to the public for self-medication. Method A comparison of the pharmaceutical scheduling requirements for medicines in six countries was undertaken in September 2003. The six countries of comparison were Australia, Canada, France, New Zealand (NZ), the United States (US), and the United Kingdom (UK). The World Self-Medication Industry website, in September 2003, listed 216 medicines available in 27 countries. Of these, 104 medicines were available in each of the six countries selected for the study. As different scheduling arrangements pertain to different forms (external, internal) or doses and pack sizes, the total number of medicines and medicine forms for comparison was 119. The scheduling of each of the 119 products was determined and compared across the six countries. Results Of the 119 medicines and medicine forms available, Australia and NZ have 38 and 34 ,prescription-only' medicines and 81 and 85 medicines available without a prescription respectively. UK, Canada and France have 47, 53, and 55 ,prescription-only' medicines and 72, 66 and 64 medicines available without a prescription. US, which has only two schedules, ,prescription-only' and ,general sale', has the highest number of ,prescription-only' drugs (66) and the least number of medicines available without a prescription (53). Conclusion The results indicate that there is a tendency for more products to be made available without a prescription in countries that have schedules with pharmacy involvement (Australia, NZ, Canada, France and UK) and a matching tendency for preparations to be held in ,prescription-only' schedules in the USA where ,pharmacy-only' schedules do not exist. The presence of ,pharmacy-only' schedules provides a structure whereby greater consumer access to medication is available. [source] Improved bounds for the chromatic number of a graphJOURNAL OF GRAPH THEORY, Issue 3 2004S. Louis Hakimi Abstract After giving a new proof of a well-known theorem of Dirac on critical graphs, we discuss the elegant upper bounds of Matula and Szekeres-Wilf which follow from it. In order to improve these bounds, we consider the following fundamental coloring problem: given an edge-cut (V1, V2) in a graph G, together with colorings of ,V1, and ,V2,, what is the least number of colors in a coloring of G which "respects" the colorings of ,V1, and ,V2, ? We give a constructive optimal solution of this problem, and use it to derive a new upper bound for the chromatic number of a graph. As easy corollaries, we obtain several interesting bounds which also appear to be new, as well as classical bounds of Dirac and Ore, and the above mentioned bounds of Matula and Szekeres-Wilf. We conclude by considering two algorithms suggested by our results. © 2004 Wiley Periodicals, Inc. J Graph Theory 47: 217,225, 2004 [source] In defence of the meltwater (megaflood) hypothesis for the formation of subglacial bedform fields,JOURNAL OF QUATERNARY SCIENCE, Issue 3 2010John Shaw Abstract Characteristics of large-scale fluting and hummocky terrain on the Canadian Prairies test glacial and meltwater hypotheses for landform genesis. These tests defend the meltwater model. Neither sedimentary nor glaciotectonic processes can fully explain such erosional landforms. Province-scale flow paths, which mark palaeo-ice streams and subglacial flood routes, contain large-scale fluting with flanking hummock terrain. Antecedent relief causes these paths to differ from other flood landscapes such as the Scablands. Proponents of the glacial hypothesis use an invalid analogy between Icelandic and Prairie landsystems. They suggest that groove-ploughing formed large-scale fluting, and that ice pushing created hummocky terrain. However, landform location, form, and extent, surface lags, truncated architecture, and landform associations favour the meltwater hypothesis. A simple thought experiment and clear understanding of the principle of least number of assumptions answer the criticisms that meltwater forms cannot cross-cut and that the meltwater hypothesis disregards proper hypothesis testing. An example of cross-cutting erosional marks supports this theory. No narrow tract of smoothed terrain with fluting terminates at the glacially thrust Neutral Hills, negating an important point in the glacial hypothesis. While neither the glacial hypothesis nor postglacial winnowing explain boulder and cobble lags with percussion marks, meltwater processes explain them well. Copyright © 2009 John Wiley & Sons, Ltd. [source] Application of an Artificial Neural Network for Simulating Robust Plasma-Sprayed Zirconia CoatingsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 5 2008Ming-Der Jean This article presents the application of the artificial neural network (ANN) of a statistically designed experiment for developing a robust wear-resistant zirconia coating. In this research, experimental design with orthogonal arrays efficiently provides enough information with the least number of experiments, reducing the cost and time. A radial basis function (RBF) network for the wear behavior is adopted. The friction and tribological properties of zirconia coatings were investigated. The microstructural feature of the coatings is also addressed in this study. It is found that the worn volumes of plasma-sprayed zirconia coatings after wear tests are greatly improved by the optimal parameters. The relationships between the microstructure of the worn surface and their properties are examined, and the results reveal a higher wear resistance and a lower worn surface roughness with a large amount of plastic deformations. These wear resistant structures formed as a result of a dense lamellar formation during sprayed zirconia coatings. The RBF network can be established efficiently. A comparison of the predicted results with that of the RBF network and the Taguchi method predictor shows average errors of 2.735% and 9.191% for the RBF network and the Taguchi method, respectively. It is experimentally confirmed that the RBF network predictions are in agreement with the experiments, and it can be reliably used for the prediction of wear for plasma sprayings. The experimental results demonstrate that the RBF network used for a statistically designed experiment is an effective, efficient, and intelligent approach for developing a robust, high efficiency, and high-quality zirconia coating process. [source] Plant neurobiology and green plant intelligence: science, metaphors and nonsenseJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 3 2008Paul C Struik Abstract This paper analyses the recent debates on the emerging science of plant neurobiology, which claims that the individual green plant should be considered as an intelligent organism. Plant neurobiology tries to use elements from animal physiology as elegant metaphors to trigger the imagination in solving complex plant physiological elements of signalling, internal and external plant communication and whole-plant organisation. Plant neurobiology proposes useful concepts that stimulate discussions on plant behaviour. To be considered a new science, its added value to existing plant biology needs to be presented and critically evaluated. A general, scientific approach is to follow the so-called ,parsimony principle', which calls for simplest ideas and the least number of assumptions for plausible explanation of scientific phenomena. The extent to which plant neurobiology agrees with or violates this general principle needs to be examined. Nevertheless, innovative ideas on the complex mechanisms of signalling, communication, patterning and organisation in higher plants are badly needed. We present current views on these mechanisms and the specific role of auxins in regulating them. Copyright © 2007 Society of Chemical Industry [source] Improper coloring of unit disk graphsNETWORKS: AN INTERNATIONAL JOURNAL, Issue 3 2009Frédéric Havet Abstract Motivated by a satellite communications problem, we consider a generalized coloring problem on unit disk graphs. A coloring is k -improper if no more than k neighbors of every vertex have the same colour as that assigned to the vertex. The k -improper chromatic number ,k(G) is the least number of colors needed in a k -improper coloring of a graph G. The main subject of this work is analyzing the complexity of computing ,k for the class of unit disk graphs and some related classes, e.g., hexagonal graphs and interval graphs. We show NP-completeness in many restricted cases and also provide both positive and negative approximability results. Because of the challenging nature of this topic, many seemingly simple questions remain: for example, it remains open to determine the complexity of computing ,k for unit interval graphs. © 2009 Wiley Periodicals, Inc. NETWORKS, 2009 [source] | ||||||||||||||||