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Intensity Analysis (intensity + analysis)
Selected AbstractsParametric intensity and the spatial arrangement of the terrestrial mollusc herbivores Deroceras reticulatum and Arion intermediusJOURNAL OF ANIMAL ECOLOGY, Issue 6 2000David A. Bohan Summary 1. Parametric intensity and spatial arrangement analyses were used to investigate the spatial pattern of the slugs Arion intermedius and Deroceras reticulatum. 2. The spatial lag of sampling (distance between sampling points) was shown to be unimportant in the intensity analyses. Rather, the 0·25 m grain scale was imposed on the whole sampling. The observed slope of the variance to mean relationships was common to both species, possibly determined by egg laying in batches at 0·25 m. However, the variance of the sample, for a given mean, was lower in summer. This corresponded with a reduction in the proportion of zero counts, which could be due to slug movement, possibly increased by predator activity, acting at the 0·25 m scale. 3. By contrast with the intensity analyses, the lag scale was important for spatial arrangement. At 0·25 m, in March 1997, the A. intermedius and D. reticulatum juveniles were aggregated, presumably about where egg batches were laid. At higher scales, the arrangements of D. reticulatum became spatially random, and A. intermedius resolved to a patch arrangement at the 16 m scale. 4. Over time, the D. reticulatum spatial arrangements remained random and independent of the previous sampling date. From March to July 1997, the A. intermedius patch persisted. A crash in abundance of both species, between July and October 1997, appeared to destroy the patch, but subsequent association suggested that the patch persisted until March 1998. The arrangements of the species were independent of one another on all sampling dates. 5. These species-specific spatial arrangements were independent of all measured environmental factors and consistent with differences in the local reproduction, survival and migration of A. intermedius and D. reticulatum. 6. This comparative study indicates that the terms aggregated, random and regular should have separate definitions for parametric intensity and spatial arrangement. Furthermore, spatial scale has different meaning in intensity and arrangement analyses. Spatial arrangements are not described by parametric intensity. Spatial arrangements change with spatial scale. Temporal changes in intensity need not manifest as changes in spatial arrangement. [source] Salinity stress adaptation competence in the extremophile Thellungiella halophila in comparison with its relative Arabidopsis thalianaTHE PLANT JOURNAL, Issue 5 2005Qingqiu Gong Summary In stark contrast to Arabidopsis, a related species, Thellungiella halophila (Thellungiella salsuginea; salt cress), displays extreme tolerance to high salinity, low humidity and freezing. High nucleotide sequence identity permits the use of tools developed for Arabidopsis for Thellungiella transcript profiling, for which a microarray platform with >25 000 DNA elements (70-mer oligonucleotides) was used. Microarray transcript profiling and intensity analysis, quantitative RT-PCR, and metabolite profiles define genes and pathways that showed shared and divergent responses to salinity stress in the two species. Shared responses are exemplified by 40% of the regulated genes functioning in confining ribosomal functions, photosynthesis and cell growth, as well as activating osmolyte production, transport activities and abscisic acid-dependent pathways. An additional 60% of regulated genes distinguished Thellungiella from Arabidopsis. Analysis of the differences showed that Arabidopsis exhibited a global defense strategy that required bulk protein synthesis, while Thellungiella induced genes functioning in protein folding, post-translational modification and protein redistribution. At 150 mm NaCl, Thellungiella maintained unimpeded growth. Transcript intensity analyses and metabolite profiles supported the microarray results, pointing towards a stress-anticipatory preparedness in Thellungiella. [source] Acute effects of caffeine and tobacco on arterial function and wave travelEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 12 2006J. Swampillai Abstract Background, Caffeine and tobacco consumption are risk factors for heart failure, but their effects remain controversial. It has been hypothesized that they cause alterations in arterial stiffness and arterial wave travel which may increase ventricular loading. In this study the authors examined the influence of these widely used stimulants on wave intensity and arterial stiffness parameters using carotid wave intensity analysis. Materials and methods, A new Doppler-based ultrasound method was used to measure the acute effects of caffeine and tobacco on wave intensity in the right common carotid artery. The measurements enabled changes in arterial stiffness parameters to be recorded. Results, In 17 subjects compared with 10 controls, caffeine increased blood pressure, early systolic wave intensity and wave speed, but late-systolic wave intensity and mid-systolic reflections were unchanged. In 11 smokers studied before and after smoking one cigarette, blood pressure and arterial stiffness increased but wave intensity was unchanged. No changes were observed in the controls. Conclusions, Increased wave intensity during ejection after caffeine suggested sympathomimetic effects on the left ventricular function. Increased wave speed in the common carotid artery implied augmented central loading after caffeine, but the absence of measurable changes in local arterial stiffness in the carotid artery suggested more complex and regional effects. Cigarette smoking acutely increased local arterial stiffness in the common carotid artery. These changes can be detected using wave intensity analysis. [source] Quality Characteristics of Spaghetti as Affected by Green and Yellow Pea, Lentil, and Chickpea FloursJOURNAL OF FOOD SCIENCE, Issue 6 2005Yonghuan H. Zhao ABSTRACT Spaghetti was made from semolina, containing 5% to 30% milled flours of green pea, yellow pea, chickpea, and lentil, respectively. Physical-chemical characteristics and descriptive sensory and consumer acceptance characteristics were measured. Spaghetti containing legume flours darkened the spaghetti (P < 0.05) but did not affect the cooked weight significantly. Cooking loss and firmness increased with an increase in legume flour content. Trypsin inhibitor activity (TIA/g) was significantly reduced after cooking. Descriptive intensity analysis showed that the firmness, pulse flavor, and color intensity of the pasta products increased with the increase in the percentages of legume flour fortification up to 30%, whereas the intensity of the shiny appearance, elasticity, and overall quality decreased. Consumers preferred control spaghetti (without legume additives) more than the spaghetti containing legume flours and they slightly liked the spaghetti with 15% lentil or green pea and the spaghetti with 20% chickpea or yellow pea. [source] A study of phase separation in peptide-loaded HPMC films using Tzero -modulated temperature DSC, atomic force microscopy, and scanning electron microscopyJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 7 2004Samana Hussain Abstract Despite the widespread use of drug-loaded polymeric systems, there is still considerable uncertainty with regard to the nature of the distribution of the drug within the polymer matrix. The aim of this investigation was to develop thermal and microscopic techniques whereby the miscibility and spatial distribution of a model peptide, cyclosporin A (CyA), in hydroxypropyl methylcellulose (HPMC) films may be studied. The new technique of Tzero -modulated temperature differential scanning calorimetry (Tzero MTDSC), scanning electron microscopy (SEM), and pulse force mode atomic force microscopy (PFM-AFM) were used in conjunction to study films prepared using a solvent evaporation process, with a solvent extraction study performed to elucidate the nature of the observed phases. Tzero MTDSC studies showed glass transitions for both the HPMC and CycA, with the Tg for the HPMC and CycA seen for the mixed systems. SEM showed two spherical phases of differing electron density. PFM-AFM also showed spheres of differing adhesion that increased in size on addition of drug. Pixel intensity analysis indicated that the smaller spheres corresponded to CycA. Exposure of the films to dichloromethane, in which CycA is soluble but HPMC is not, resulted in the presence of voids that corresponded well to the spheres suggested to correspond to the drug. It was concluded that the system had undergone extensive or complete phase separation, and that the thermal and microscopic techniques outlined above are an effective means by which this issue may be studied. © 2004 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 93:1672,1681, 2004 [source] Resonance Raman spectroscopic studies of [Ru(phen)2qdppz]2+ and its interactions with calf thymus DNAJOURNAL OF RAMAN SPECTROSCOPY, Issue 1 2004B. Abraham Abstract Resonance Raman (RR) spectroscopy was employed to study the metal to ligand charge transfer (MLCT) and intraligand transition (IL) state of the [Ru(phen)2qdppz]2+ complex, where phen = 1, 10-phenanthroline and qdppz = naphtho[2,3- a]dipyrido[3,2- h:2,,3, - f]phenazine-5,18-dione. The vibrational bands were assigned based on the data available for [Ru(phen)2dppz]2+ (dppz = dipyrido[3,2- a:2,,3, - c]phenazine), [Ru(dppz)3]2+ and [Ru(phen)3]2+. The tail end of the MLCT band is inferred to be the Ru , qdppz localized transition based on vibrational intensity analysis. On intercalation with DNA, the modes assigned to qdppz decrease in intensity owing to ,, stacking interactions with the DNA bases. RR data show that the above complex binds to DNA through intercalation via the qdppz moiety. Copyright © 2003 John Wiley & Sons, Ltd. [source] Proteomic analysis of differentially expressed proteins in Penaeus vannamei hemocytes upon Taura syndrome virus infectionPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 19 2007Phattara-orn Chongsatja Abstract To understand molecular responses of crustacean hemocytes to virus infection, we applied 2-DE proteomics approach to investigate altered proteins in hemocytes of Penaeus vannamei during Taura syndrome virus (TSV) infection. At 24,h postinfection, quantitative intensity analysis and nano-LC-ESI-MS/MS revealed 11 forms of 8 proteins that were significantly up-regulated, whereas 9 forms of 5 proteins were significantly down-regulated in the infected shrimps. These altered proteins play important roles in host defense (hemocyanin, catalase, carboxylesterase, transglutaminase, and glutathione transferase), signal transduction (14-3-3 zeta), carbohydrate metabolism (acetylglucosamine pyrophosphorylase), cellular structure and integrity (beta-tubulin, beta-actin, tropomyosin, and myosin), and ER-stress response (protein disulfide isomerase). Semiquantitative RT-PCR and Western blot analysis confirmed the upregulation of 14-3-3 at both mRNA and protein levels. Interestingly, several altered protein spots were identified as fragments of hemocyanin. Mass spectrometric analysis showed that the hemocyanin spots at acidic and basic regions represented the C- and N-terminal hemocyanin fragments, respectively. As three-quarters of C-terminal fragments were up-regulated, whereas two-thirds of N-terminal hemocyanin fragments were down-regulated, we therefore hypothesize that C- and N-terminal hemocyanin fragments may have differential roles in hemocytes. Further investigation of these data may lead to better understanding of the molecular responses of crustacean hemocytes to TSV infection. [source] Salinity stress adaptation competence in the extremophile Thellungiella halophila in comparison with its relative Arabidopsis thalianaTHE PLANT JOURNAL, Issue 5 2005Qingqiu Gong Summary In stark contrast to Arabidopsis, a related species, Thellungiella halophila (Thellungiella salsuginea; salt cress), displays extreme tolerance to high salinity, low humidity and freezing. High nucleotide sequence identity permits the use of tools developed for Arabidopsis for Thellungiella transcript profiling, for which a microarray platform with >25 000 DNA elements (70-mer oligonucleotides) was used. Microarray transcript profiling and intensity analysis, quantitative RT-PCR, and metabolite profiles define genes and pathways that showed shared and divergent responses to salinity stress in the two species. Shared responses are exemplified by 40% of the regulated genes functioning in confining ribosomal functions, photosynthesis and cell growth, as well as activating osmolyte production, transport activities and abscisic acid-dependent pathways. An additional 60% of regulated genes distinguished Thellungiella from Arabidopsis. Analysis of the differences showed that Arabidopsis exhibited a global defense strategy that required bulk protein synthesis, while Thellungiella induced genes functioning in protein folding, post-translational modification and protein redistribution. At 150 mm NaCl, Thellungiella maintained unimpeded growth. Transcript intensity analyses and metabolite profiles supported the microarray results, pointing towards a stress-anticipatory preparedness in Thellungiella. [source] Hemodynamics of a Pulsatile Left Ventricular Assist Device Driven by a Counterpulsation Pump in a Mock CirculationARTIFICIAL ORGANS, Issue 4 2006Ashraf William Khir Abstract:, The BCM (CardialCare, Minneapolis, MN, U.S.A.) is a pusher-plate pulsatile left ventricular assist device (LVAD) that is operated by counterpulsation pumps. The purpose of this work was to assess the fluid dynamics associated with operating the BCM in a mock circulation, and also to examine the similarities between hemodynamic parameters produced by this device in vitro and those produced by the left ventricle (LV) in vivo. The BCM was connected to a true size silicon rubber aorta and operated by an intra-aortic balloon pump. We examined the performance of the device at two system pressures (6.5 and 8 kPa); at three heart rates (60, 80, and 100 bpm); and at three pumping frequencies (1:1, 1:2, 1:3). Pressure and flow were measured in the upper descending aorta, and wave intensity analysis was used to calculate the peak intensity and energy of the compression and expansion waves. Pressure and flow waveforms produced by the BCM LVAD in vitro under different loading conditions were similar to those observed in vivo under similar loadings. Pusher-plate-type LVADs can produce compression and expansion waves similar to those generated by healthy LV in vivo. [source] A statistic for local intensity differences: robustness to anisotropy and pseudo-centering and utility for detecting twinningACTA CRYSTALLOGRAPHICA SECTION D, Issue 7 2003Jennifer E. Padilla A new approach to analyzing macromolecular single-crystal X-ray diffraction intensity statistics is presented. Instead of considering reflections in resolution shells, differences between local pairs of reflection intensities are taken and normalized separately. When the two reflections to be compared (having intensities I1 and I2, respectively) are chosen appropriately, the behavior of the parameter L = (I1 , I2)/(I1 + I2) is insensitive to phenomena that tend to confound traditional intensity statistics, such as anisotropic diffraction and pseudo-centering. The distributions and expected values for L take simple forms when the intensity data are from ordinary crystals or from perfectly twinned specimens. The robustness of the approach is demonstrated with examples using real proteins whose diffraction data appear aberrant by other methods of intensity analysis. The new statistic is better suited than other available methods for diagnosing perfect hemihedral twinning. [source] | ||||||||||||||||