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Uniform Pattern (uniform + pattern)
Selected AbstractsPiezoelectric inkjet printing of a cross-hatch immunoassay on a disposable nylon membraneBIOTECHNOLOGY JOURNAL, Issue 2 2009Thomas N. Stewart Abstract The development of a cost-effective method for manufacturing immunoassays is a key step towards their commercial use. In this study, a piezoelectric inkjet printer and a nylon membrane were used to fabricate a disposable immunoassay. Using a piezoelectric inkjet printer, a cross-hatch pattern of goat anti-mouse antibody (G,M) and rabbit anti-horseradish peroxidase (R,HRP) antibody were deposited on the nylon membrane. These patterns were subsequently treated with a solution containing rabbit anti-goat antibody labeled with horseradish peroxidase (R,G-HRP). The effectiveness of the immobilization process was examined using tetramethylbenzidine (TMB), which oxidizes in the presence of HRP to form a visible precipitate. Optical evaluation of the TMB precipitate was used to assess the precision of the features in the inkjet-printed pattern as well as antibody functionality following inkjet printing. Uniform patterns that contained functional antibodies were fabricated using the piezoelectric inkjet printer. These results suggest that piezoelectric inkjet printing may be used to fabricate low-cost disposable immunoassays for biotechnology and healthcare applications. [source] Dichotic listening deficits in children with dyslexiaDYSLEXIA, Issue 1 2008Deborah W. Moncrieff Abstract Several auditory processing deficits have been reported in children with dyslexia. In order to assess for the presence of a binaural integration type of auditory processing deficit, dichotic listening tests with digits, words and consonant,vowel (CV) pairs were administered to two groups of right-handed 11-year-old children, one group diagnosed with developmental dyslexia and an age-matched control group. Dyslexic children performed more poorly than controls from their left ears when listening to digits and words and from their right ears when listening to CVs. Direction of ear advantage varied across individuals in both groups when tested with digits and CVs, but ear advantage was stable with words. Several factors that may have contributed to inconsistencies in direction of ear advantage are discussed. When the children were tested in a directed response mode, degree of ear advantage differed significantly between groups with both words and digits. More dyslexic than control children demonstrated clinically significant reductions in dichotic listening performance, but no uniform pattern of deficit emerged. Only the double correct score and the left ear score with CV pairs were predictive of word recognition performance in dyslexic children. Binaural integration deficits are present in some children with dyslexia. Auditory processing disorder assessment may help delineate factors that underlie or are associated with reading impairment in this population. Copyright © 2007 John Wiley & Sons, Ltd. [source] Varying clinical presentations at onset of type 1 diabetes mellitus in children , epidemiological evidence for different subtypes of the disease?PEDIATRIC DIABETES, Issue 4 2001Andreas Neu Abstract: Objective:, On the basis of 2121 case observations between 1987 and 1997, we describe the clinical and laboratory characteristics of diabetes mellitus type 1 at its onset. Our objective is to analyze whether clinical presentation follows a uniform pattern or whether there is evidence for different subtypes. Research design and methods: Thirty-one pediatric hospitals and one diabetes center in Baden-Wuerttemberg (BW), Germany, participated in this study. The hospital records of 2121 children below 15 yr of age were examined retrospectively. Statistical analysis was done after logarithmic transformation into a normal distribution. Results: The average duration of symptoms was found to be 15.2 d (95% CI (Confidence Intervals) = 14.3,16.1) ranging between 2.0 and 180 d (95% central range). The most frequent symptoms were polyuria and polydipsia; 7.2% presented with altered level of consciousness. The mean blood glucose value was 407.9 mg/dL (95% CI = 400.0,416.0), corresponding to 23.3 mmol/L (95% CI = 22.8,23.8). The median pH value was 7.35 (95% CI = 7.34,7.36), and the median base excess was ,5 mmol/L (95% CI =,5 to ,4). The younger patients had a shorter duration of symptoms and suffered most frequently from ketoacidosis. Conclusions: Although the symptoms of diabetes at its onset follow a uniform pattern, the clinical presentation and duration of symptoms indicate that there may be various forms of type 1 diabetes. [source] Position dependence of the 13C chemical shifts of ,-helical model peptides.PROTEIN SCIENCE, Issue 11 2004Fingerprint of the 20 naturally occurring amino acids Abstract The position dependence of the 13C chemical shifts was investigated at the density functional level for ,-helical model peptides represented by the sequence Ac-(Ala)i -X-(Ala)j -NH2, where X represents any of the 20 naturally occurring amino acids, with 0 , i , 8 and i + j = 8. Adoption of the locally dense basis approach for the quantum chemical calculations enabled us to reduce the length of the chemical-shift calculations while maintaining good accuracy of the results. For the 20 naturally occurring amino acids in ,-helices, there is (1) significant variability of the computed 13C shielding as a function of both the guest residue (X) and the position along the sequence; for example, at the N terminus, the 13C, and 13C, shieldings exhibit a uniform pattern of variation with respect to both the central or the C-terminal positions; (2) good agreement between computed and observed 13C, and 13C, chemical shifts in the interior of the helix, with correlation coefficients of 0.98 and 0.99, respectively; for 13C, chemical shifts, computed in the middle of the helix, only five residues, namely Asn, Asp, Ser, Thr, and Leu, exhibit chemical shifts beyond the observed standard deviation; and (3) better agreement for four of these residues (Asn, Asp, Ser, and Thr) only for the computed values of the 13C, chemical shifts at the N terminus. The results indicate that 13C,, but not 13C,, chemical shifts are sensitive enough to reflect the propensities of some amino acids for specific positions within an ,-helix, relative to the N and C termini of peptides and proteins. [source] Seasonality of a Diverse Beetle Assemblage Inhabiting Lowland Tropical Rain Forest in AustraliaBIOTROPICA, Issue 3 2009Peter S. Grimbacher ABSTRACT One of the least understood aspects of insect diversity in tropical rain forests is the temporal structuring, or seasonality, of communities. We collected 29,986 beetles of 1473 species over a 4-yr period (45 monthly samples), with the aim to document the temporal dynamics of a trophically diverse beetle assemblage from lowland tropical rain forest at Cape Tribulation, Australia. Malaise and flight interception traps were used to sample adult beetles at five locations at both ground and canopy levels. Beetles were caught throughout the year, but individual species were patchy in their temporal distribution, with the 124 more abundant species on average being present only 56 percent of the time. Climatic variables (precipitation, temperature, and solar radiation) were poorly correlated with adult beetle abundance, possibly because: (1) seasonality of total beetle abundance was slight; (2) the peak activity period (September,November) did not correspond to any climatic maxima or minima; or (3) responses were nonlinear owing to the existence of thresholds or developmental time-lags. Our results do not concur with the majority of tropical insect seasonality studies suggesting a wet season peak of insect activity, perhaps because there is no uniform pattern of insect seasonally for the humid tropics. Herbivores showed low seasonality and individual species' peaks were less temporally aggregated compared to nonherbivores. Canopy-caught and larger beetles (> 5 mm) showed greater seasonality and peaked later in the year compared to smaller or ground-caught beetles. Thus seasonality of adult beetles varied according to the traits of feeding ecology, body size, and habitat strata. [source] Taphonomy and zooarchaeology of the Upper Palaeolithic cave of Dzudzuana, Republic of GeorgiaINTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 2 2008G. Bar-Oz Abstract We present the results of a detailed taphonomic and zooarchaeological study of the faunal remains from the Upper Palaeolithic layers of Dzudzuana Cave, Republic of Georgia. This study presents the first carefully analysed Upper Palaeolithic faunal assemblage from the southern Caucasus and thus serves as a significant point of reference for inter-regional studies of Upper Palaeolithic subsistence in Eurasia. A series of intra-site taphonomic comparisons are employed to reconstruct the depositional history of the bone assemblages within the different occupational phases at the site and to investigate subsistence, meat procurement and bone-processing strategies. Caucasian tur (Capra caucasica), aurochs (Bos primigenius) and steppe bison (Bison priscus) were the major prey species throughout the Upper Palaeolithic. Their frequencies do not change significantly over time, and nor does bone preservation vary by layer. The assemblage is characterised by significant density-mediated biases, caused by both human bone-processing behaviours and in situ post-burial bone attrition. Bone marrow extraction produced large numbers of unidentified bone fragments, many exhibiting green bone fractures. The density and size of bone assemblages and the extent of fragmentation indicate that Dzudzuana Cave was repeatedly occupied by Upper Palaeolithic foragers over many years. Skeletal part representation and butchery marks from all stages of carcass processing suggest that prey occasionally underwent field butchery. Intra-site taphonomic comparisons highlight uniform patterns of cultural and economic behaviours related to food procurement and processing strategies. Copyright © 2007 John Wiley & Sons, Ltd. [source] Sexual selection research on spiders: progress and biasesBIOLOGICAL REVIEWS, Issue 3 2005Bernhard A. Huber ABSTRACT The renaissance of interest in sexual selection during the last decades has fuelled an extraordinary increase of scientific papers on the subject in spiders. Research has focused both on the process of sexual selection itself, for example on the signals and various modalities involved, and on the patterns, that is the outcome of mate choice and competition depending on certain parameters. Sexual selection has most clearly been demonstrated in cases involving visual and acoustical signals but most spiders are myopic and mute, relying rather on vibrations, chemical and tactile stimuli. This review argues that research has been biased towards modalities that are relatively easily accessible to the human observer. Circumstantial and comparative evidence indicates that sexual selection working via substrate-borne vibrations and tactile as well as chemical stimuli may be common and widespread in spiders. Pattern-oriented research has focused on several phenomena for which spiders offer excellent model objects, like sexual size dimorphism, nuptial feeding, sexual cannibalism, and sperm competition. The accumulating evidence argues for a highly complex set of explanations for seemingly uniform patterns like size dimorphism and sexual cannibalism. Sexual selection appears involved as well as natural selection and mechanisms that are adaptive in other contexts only. Sperm competition has resulted in a plethora of morphological and behavioural adaptations, and simplistic models like those linking reproductive morphology with behaviour and sperm priority patterns in a straightforward way are being replaced by complex models involving an array of parameters. Male mating costs are increasingly being documented in spiders, and sexual selection by male mate choice is discussed as a potential result. Research on sexual selection in spiders has come a long way since Darwin, whose spider examples are reanalysed in the context of contemporary knowledge, but the same biases and methodological constraints have persisted almost unchanged through the current boom of research. [source] | ||||||||||