Increase In Maximum Intensity Research Articles

Spatiotemporally contiguous precipitation events across China: Role of atmospheric rivers and tropical cyclones in heavy precipitation

Precipitation events exhibit a spatiotemporal continuity since they move across both space and time, however, the joint spatiotemporal characteristics of precipitation events are often neglected, and the role of Atmospheric rivers (ARs) and tropical cyclones (TCs) in the events has not been systematically explored. To solve these problems, this study seeks to detect and characterize the three-dimensional (latitude + longitude + time) structures of spatiotemporally contiguous precipitation events, distinguish the heavy events associated with ARs or TCs, and systematically explore the different roles of these events. We do so by combining Forward-in-Time algorithm, an object-based physical event detecting algorithm, with TMPA precipitation estimates to detect spatiotemporally contiguous precipitation events over China, and an AR detection technique considering a combination of fixed lower limit and Integrated Water Vapor Transport percentile threshold is adopted to identify ARs. The heavy events are defined to analyze the differences of the events associated with TCs and ARs as a function of precipitation total, duration, and intensity. Results show that approximately half or more of precipitation events are shorter than 6-hour, and the precipitation total of each event is strongly correlated with maximum intensity and average intensity across China. The heavy events normally occur in southern, center, northern, and southwestern regions, where have approximately 10 to 40 heavy events at each grid. The fraction of heavy events associated with TCs generally increase for events with larger precipitation totals and for events with higher maximum intensity, until all of events are associated with TCs. The percentages of events associated with ARs as well normally increase as precipitation totals and maximum intensity increase up to around 150 mm and 30 mm/h, respectively. Our findings show that the events associated with TCs or ARs exhibit distinct different characteristics, and suggest that the different spatiotemporal dynamics should be sufficient considered in contiguous events analyses in different regions.

Oedema on STIR modified the effect of amoxicillin as treatment for chronic low back pain with Modic changes\u2014subgroup analysis of a randomized trial

ObjectiveTo evaluate potential MRI-defined effect modifiers of amoxicillin treatment in patients with chronic low back pain and type 1 or 2 Modic changes (MCs) at the level of a previous lumbar disc herniation (index level).MethodsIn a prospective trial (AIM), 180 patients (25–64 years; mean age 45; 105 women) were randomised to receive amoxicillin or placebo for 3 months. Primary outcome was the Roland-Morris Disability Questionnaire (RMDQ) score (0–24 scale) at 1 year. Mean RMDQ score difference between the groups at 1 year defined the treatment effect; 4 RMDQ points defined the minimal clinically important effect. Predefined baseline MRI features of MCs at the index level(s) were investigated as potential effect modifiers. The predefined primary hypothesis was a better effect of amoxicillin when short tau inversion recovery (STIR) shows more MC-related high signal. To evaluate this hypothesis, we pre-constructed a composite variable with three categories (STIR1/2/3). STIR3 implied MC-related STIR signal increases with volume ≥ 25% and height > 50% of vertebral body and maximum intensity increase ≥ 25% and presence on both sides of the disc. As pre-planned, interaction with treatment was analysed using ANCOVA in the per protocol population (n = 155).ResultsThe STIR3 composite group (n = 41) and STIR signal volume ≥ 25% alone (n = 45) modified the treatment effect of amoxicillin. As hypothesised, STIR3 patients reported the largest effect (− 5.1 RMDQ points; 95% CI − 8.2 to − 1.9; p for interaction = 0.008).ConclusionsPredefined subgroups with abundant MC-related index-level oedema on STIR modified the effect of amoxicillin. This finding needs replication and further support.Key Points• In the primary analysis of the AIM trial, the effect of amoxicillin in patients with chronic low back pain and type 1 or 2 MCs did not reach the predefined cut-off for clinical importance.• In the present MRI subgroup analysis of AIM, predefined subgroups with abundant MC-related oedema on STIR reported an effect of amoxicillin.• This finding requires replication and further support.

Evaluation of trigeminal pungency perception of allyl isothiocyanate – A time intensity (TI) study

Allyl isothiocyanate, the primary pungent substance within mustard, horseradish, and wasabi, causes a burning sensation and a lachrymatory effect during consumption. In this time intensity study, the sensory perception of the chemical stimulus allyl isothiocyanate was evaluated in water-based, oil-based, and mustard recipe-based carrier matrices. The results indicate that perceived pungency intensity and time course of perception were both strongly dependent upon allyl isothiocyanate concentration and the composition of the carrier matrices. Increasing allyl isothiocyanate concentrations led to a significant (p < 0.05) increase in maximum intensity of pungency (Imax) in all tested carrier matrices. The intensity of pungency perception for allyl isothiocyanate decreased depending upon the specific matrix used. Specifically, this decrease occurred in the order oil-based carrier < mustard-based carrier < water-based carrier at similar allyl isothiocyanate concentrations. The values for end time of pungency perception (TEnd) and duration of decreasing phase (DURDec) indicate that increasing allyl isothiocyanate concentrations prolong the duration of pungency perception. Allyl isothiocyanate was perceived longer in water than in oil- and mustard-based carrier matrices.

Ударное сжатие лазерной плазмы для увеличения интенсивности сигнала при спектрометрическом определении микрокомпонентов в рудах

AbstractWe have studied the confinement of laser plasma by shock waves (also known as “spatial confinement” induced on an ore sample, as exemplified by changes in the intensity of Ag I 328.07 nm and Au I 267.60 nm emission lines. It is established that the maximum increase in intensity of these lines is observed at 2- to 2.5-μs delay, which corresponds to an increase in the plasma temperature up to 5900 K. The signal-to-noise ratio upon the spatial confinement of plasma is somewhat reduced, but the overall growth of signal intensity provides increase in the sensitivity of laser-induced breakdown spectrometry for determining trace elements in ores.

Confinement of Laser Plasma by Shock Waves for Increasing Signal Intensity in Spectrochemical Determination of Trace Elements in Ores

We have studied the confinement of laser plasma by shock waves (also known as “spatial confinement” induced on an ore sample, as exemplified by changes in the intensity of Ag I 328.07 nm and Au I 267.60 nm emission lines. It is established that the maximum increase in intensity of these lines is observed at 2- to 2.5-μs delay, which corresponds to an increase in the plasma temperature up to 5900 K. The signal-to-noise ratio upon the spatial confinement of plasma is somewhat reduced, but the overall growth of signal intensity provides increase in the sensitivity of laser-induced breakdown spectrometry for determining trace elements in ores.

Expression of VEGF and collagen XVIII in meningiomas: correlations with histopathological and MRI characteristics

The objective of this study was to assess the possibility of predicting histological characteristics of meningiomas on the basis of preoperative MRI and the correlation of the expression of vascular endothelial growth factor (VEGF) and collagen XVIII with histological parameters already established as predictive of the course of these tumors. Expression of VEGF and collagen XVIII as well as other histological characteristics was examined in meningioma tissues from 20 patients. Preoperative MRI, including dynamic imaging of contrast enhancement, was analyzed. Times to maximum enhancement and maximum intensity increase were noted from dynamic imaging. The relative intensity of the tumor in fluid-attenuated inversion recovery (FLAIR), T2-weighted and contrast enhanced T1-weighted images, as well as volumes of tumor and edema, was calculated. The edema-tumor volume ratio was defined as the edema index (EI). Both VEGF and collagen XVIII were expressed in all meningioma samples. Edema was present in 60 % of cases. The strongest correlation of VEGF expression was to EI. Among histological parameters, microvessel density (MVD) and cellularity correlated moderately with VEGF. Collagen XVIII expression correlated strongly with the maximal intensity increase after contrast agent administration (ρ = 0.71, P = 0.001) as well as with MVD and intensity of the meningioma on FLAIR images. Meningiomas with faster and more intense enhancement in dynamic studies, indicative of good tumor blood supply and permeability of vasculature, are associated with high levels of collagen XVIII and VEGF expression. Occurrence of peritumoral edema in meningiomas is strongly correlated with expression of VEGF.

Folate receptor-mediated targeted polymeric gadolinium complexes for magnetic resonance imaging in pulmonary tumor xenografts

Targeted delivery is a highly desirable strategy for diagnostic imaging due to enhanced efficacy and reduced dosage/toxicity. The need to develop target-specific magnetic resonance imaging (MRI) contrast agents to aid in disease characterization is highly essential. In this study, a specific contrast agent, Gd-DTPA-poly-L-lysine (PL-Gd-DTPA)-folate, was synthesized and evaluated for its efficacy as a targeted agent for the imaging of tumors that overexpress the folate receptor. Folic acid was conjugated to PL-Gd-DTPA via the ε-amino groups. The receptor binding properties of folate-PL-Gd-DTPA were studied in cultured tumor cells that overexpressed the folate receptor. The tumor-selecting properties of folate-PL-Gd-DTPA were then evaluated in BALB/c mice bearing subcutaneously implanted folate receptor-positive tumors. Tissue MR signal intensities were measured at six different time-points. In the in vitro study, the folate-PL-Gd-DTPA was able to bind to these cells, which overexpressed the folate receptor, as with free folic acid. Excellent tumor selectivity was also shown in the animal model; after the success of injection of folate-PL-Gd-DTPA, a maximum intensity increase of 125.4% was observed from pre-injection compared to post-injection images of the tumor at the 48 h time-point. The liver enhancement was non-specific and the muscle signal intensity at any time-point after injection showed no statistical difference with that observed before injection. Folate-PL-Gd-DTPA is a promising, novel receptor-specific MRI contrast agent with potential applications in the imaging of human folate receptor-positive tumors.

Metal-enhanced fluorescence of an organic fluorophore using gold particles.

Particulate gold films were deposited on glass substrates by vapor deposition. Rabbit immunoglobulin G (IgG) was immobilized by physiosorption and then Alexa Fluor anti Rabbit IgG was bound to the protein-coated surfaces. Fluorescence was enhanced with increasing the Au thickness and reached saturation at 30 nm when Alexa Fluor555 anti IgG was used. We also examined the effect of silica spacers between the gold film and the labeled protein. The maximum enhancement was dependent on the thickness of silica and reach maximum at 10 nm. The maximum increase in intensity was about 6-fold. We also bound Alexa Fluor-680 anti IgG to the protein-coated surface, and the maximum enhancement was about 10-fold.

Enhancement of laser plasma extreme ultraviolet emission by shockwave-laser interaction

A double laser pulse heating scheme has been applied to generate plasmas with enhanced emission in the extreme ultraviolet (EUV). The plasmas were produced by focusing two laser beams (prepulse and main pulse) with a small spatial separation between the foci on a xenon gas jet target. Prepulses with ps-duration were applied to obtain high shockwave densities, following indications of earlier published results obtained using ns prepulses. EUV intensities around 13.5 nm and in the range 5–20 nm were recorded, and a maximum increase in intensity exceeding 2 was measured at an optimal delay of 140 ns between prepulse and main pulse. The gain in intensity is explained by the interaction of the shockwave produced by the prepulse with the xenon in the beam waist of the main pulse. Extensive simulation was done using the radiative magnetohydrodynamic code Z*.

Opal-A and associated microbes from Wairakei, New Zealand: the first 300 days

AbstractAll samples of silica sinter, &lt;2 y old taken from the discharge drain of the Wairakei geothermal power station and the Rainbow Terrace of Orakei Korako, consist of non-crystalline opal-A. This silica phase deposits directly upon the concrete drain wall and filamentous templets, extending from this wall, afforded by the microbial community present in the drain, whose nature was determined by a culture- independent strategy that entailed construction, fingerprinting and sequencing of a 16S clone library. The bacterial community is dominated by five major groups of organisms, present in approximately equal proportions, and which account for ∼50% of the community. None of the 16S sequences from these dominant groups yielded a perfect match with 16S sequences for named organisms in the international databases. However one dominant group clusters withHydrogenophilus thermoluteus,a thermophilic filamentous bacterium, and two cluster with putatively thermophilic members of theCyanobacteriaand green non-sulphur bacteria respectively. Initial opal-A deposits rapidly as agglomerations of silica nanospheres that, in turn, form chains of coalesced, oblate, microspheres &lt;0.4 x 0.2 mm about the barbicel-like filaments, to produce a mat of fine woven strands. The majority of individual filaments are &lt;8 μm long and 0.8 mm wide but may be up to 55 mm long by 1 mm wide. Where laminar flow dominates, most strands develop parallel to the drain current but some strands crisscross while others protrude above the mat surface. Where flow is turbulent, strands lack preferred orientation and some adopt a helical form. In general, following deposition, the values of the scattering broadband at half (FWHM) and three quarters (FWTM) of the maximum intensity decrease with increasing sample age. The behaviour of the band at one quarter maximum intensity (FWQM) is less consistent, but, in general, the youngest sinters possess the highest FWQM, FWHM and FWTM values that prove independent of fabric type. Opal-A silica matures following its removal from the parent fluid, especially where the sinter surface is filmed by water. A continual movement of silica is shown by a second generation of microspheres formed on the silica mat surface, by an increase in size of the initial microspheres, and by an increase in maximum intensity of the X-ray scattering broadbands. Similar silica aging behaviour occurs among young sinters developed upon microbial mats at Orakei Korako. The deposition and aging processes accord with the known behaviour of juvenile opaline silica in both natural and artificial systems whose pH, temperature and dissolved salt content are similar to Wairakei and Rainbow terrace: gelling of silica is favoured by the high pH (∼8.3) and temperature (∼60°C) of the Wairakei discharge fluid but the high dissolved salt content of the water (Na+= 930 μg/g, Ca2+= 12 μg/g, Cl = 1500 μg/g) and abundant microbial community facilitate rapid and copious flocculation of solid silica within the drain, in contrast to the slower accumulation on the natural sinter terrace at lower temperature (30—45°C) from less saline dilute bicarbonate-chloride waters (Na+= 180 μg/g, Ca2+= 0.2 μg/g, Cl = 400 μg/g, pH = 8.1).

Temporal evolution of different temperature plasma during explosive events

High cadence observations (10 s exposure time) obtained with the SUMER spectrometer on-board SoHO in the Ly 6 (20 000 K) and S vi (200 000 K) lines reveal new insight on the nature of explosive events. A time delay in the response of the S vi line with respect to the Ly 6 line has been observed, with the Ly 6 line responding with about 20–40 s earlier. A temporal series obtained with 30 s exposure time and covering the entire Lyman series plus O i, C ii and S vi (temperature range from 15 000 to 200 000 K) has also been explored showing the response of all these lines during transient phenomena. New common features linking explosive events and blinkers were found. During explosive events, the central intensity increases between 1.6 and 2.0 times the pre-event value while the same range of intensity increase was already reported during blinker phenomena. On the other hand the maximum intensity increase in Ly 6 was only 13%.

Human apolipoprotein C-II forms twisted amyloid ribbons and closed loops.

Human apolipoprotein C-II (apoC-II) self-associates in solution to form aggregates with the characteristics of amyloid including red-green birefringence in the presence of Congo Red under cross-polarized light, increased fluorescence in the presence of thioflavin T, and a fibrous structure when examined by electron microscopy. ApoC-II was expressed and purified from Escherichia coli and rapidly exchanged from 5 M guanidine hydrochloride into 100 mM sodium phosphate, pH 7.4, to a final concentration of 0.3 mg/mL. This apoC-II was initially soluble, eluting as low molecular weight species in gel filtration experiments using Sephadex G-50. Circular dichroism (CD) spectroscopy indicated predominantly unordered structure. Upon incubation for 24 h, apoC-II self-associated into high molecular weight aggregates as indicated by elution in the void volume of a Sephadex G-50 column, by rapid sedimentation in an analytical ultracentrifuge, and by increased light scattering. CD spectroscopy indicated an increase in beta-sheet content, while fluorescence emission spectroscopy of the single tryptophan revealed a blue shift and an increase in maximum intensity, suggesting repositioning of the tryptophan into a less polar environment. Electron microscopy of apoC-II aggregates revealed a novel looped-ribbon morphology (width 12 nm) and several isolated closed loops. Like all of the conserved plasma apolipoproteins, apoC-II contains amphipathic helical regions that account for the increase in alpha-helix content on lipid binding. The increase in beta-structure accompanying apoC-II fibril formation points to an alternative folding pathway and an in vitro system to explore the general tendency of apolipoproteins to form amyloid in vivo.

Using repeated ingestion to determine the effect of sweetness, viscosity and oiliness on temporal perception of soymilk astringency

Astringency is a persistent sensation which increases upon repeated ingestion. To evaluate the effect of viscosity, sucrose and oil on perception of astringency during consumption of soymilk, a sequential sipping time–intensity (TI) procedure was utilized. For each soymilk, judges sipped the first of four ingestions and initiated the continuous recording of astringency intensity. Each sip was expectorated at 10 s after ingestion, and sipped 10 s after expectoration of the previous stimulus. After the fourth sample, judges rated astringency for 30 s. Traditional TI parameters, as well as rate of onset for each sip and increase in maximum intensity per sip were extracted from the TI curves. Maximum astringency (IMAX) increased significantly with successive sips as did the astringency at the time of sipping. Time to IMAX decreased from sip 1 to 3, but was longer for sip 4, which may be an artifact of the rapid test pace. Although addition of 60 g l −1 canola oil had no affect on astringency, adding 40 g l −1 sucrose or increasing viscosity by 5 cp with CMC significantly lowered all astringency parameters. The reduction in astringency by CMC may result from restoration of salivary lubrication and in part by chelation or hydrogen bonding of CMC to the astringents reducing their ability to bind to salivary proteins. The reduction in astringency produced by sucrose is more probably due to a cognitive process. ©

How Good Is Intercenter Agreement in the Identification of Embolic Signals in Carotid Artery Disease?

There has been concern regarding the reproducibility of the detection of embolic signals, particularly in patients with carotid artery stenosis in whom the signals are of low intensity. No published studies have examined inter-center agreement in reporting specific embolic signals or the factors responsible for any lack of agreement. We examined reproducibility between two centers in which widely differing proportions of embolic signals have previously been reported in patients with carotid artery stenosis. Recordings from the middle cerebral artery of eight patients with ipsilateral carotid artery stenosis in whom embolic signals had been detected during a previously study were independently examined by three experienced observers in one center and by one experienced observer in another center. We calculated agreement within and between centers by estimating the probability that one observer would identify a specific embolic signal if other observers had identified it (a probability of 1 indicates complete agreement). The influence of different characteristics of the embolic signal on the probability of its detection as an embolic signal was determined. A high level of agreement in the identification of specific embolic signals was found. This was similar between all observers (.90), between the three observers in one center (.89), and between observers in the two different centers (.94). The probability of detection was independently related to the relative intensity of the embolic signal (P<.0001). It was less (although significantly) independently related to the position of the embolic signal in the cardiac cycle (P=.02), with signals in systole being more reliably detected. There was no independent relationship between the probability of detection and either the duration of the embolic signal or the velocity at the maximum intensity increase. The use of threshold intensity as a criterion for embolic signal detection increased interobserver agreement but reduced the sensitivity in detecting signals. The high level of interobserver agreement suggests that the technique is sufficiently reproducible for clinical use.

Pharmacokinetic studies of different echo-contrast agents in the cerebral circulation of dogs

Ultrasound contrast agents (UCAs) are improving the signal-to-noise ratio of the reflected ultrasound so that Doppler frequency spectra can be recorded even under poor sonographic conditions. This is of particular diagnostic value in transcranial Doppler sonography. Depending on specific pharmacologic properties, echocontrast agents may cause different increase and duration in Doppler signal amplitude. We used a dog model to study the temporal profile of Doppler signal amplitude after application of a phospholipid-containing echocontrast agent (BY 963). In addition, we compared it with a contrast agent containing albumin (Albunex). Spherosome suspension BY 963 resulted in a dose-dependent increase in the duration of ultrasound amplification (Doppler enhancement of 1 mL, 3 mL and 10 mL of BY 963 per animal: 62.4 ± 8.4, 72.8 ± 9.2 and 67.7 ± 4.2 s, respectively, n = 6). Detection of BY 963 in the extracranial jugular vein demonstrated that the UCA passes through the cerebral microcirculation (cerebral transit time was 2.2 ± 0.2 s, n = 4). The signal enhancement lasted longer using the spherosome suspension compared with the albumin-containing solution (77.2 ± 11.6 and 31.1 ± 3.7 s, respectively, n = 6), and the maximum increase in intensity was more pronounced (27.0 ± 2.0 and 17.5 ± 2.2 dB, respectively, n = 6).

A nuclear magnetic resonance investigation of the upper airways in ferrets. I. Effects of histamine and methacholine.

Alterations induced in the upper airways of ferrets by intranasal provocation with methacholine (MC) and histamine (HS) were monitored using proton magnetic resonance imaging (MRI) and spin-spin relaxation rate (R2) measurements. Both MC and HS cause a significant increase in the MRI signal intensity and a decrease in R2 in the nasal turbinates. A dose-dependent response is observed for 20 to 315 nmol of HS, with a maximum increase in intensity of ca. 50% occurring above 80 nmol. A single unilateral challenge with MC yields a 62 +/- 3% increase in intensity. Control animals (saline-treated) show little change in image intensity. MC and HS cause decreases in the proton R2 by -27.0 +/- 5.5% and -17.2 +/- 4.3%, respectively. These data are indicative of an accumulation of fluid in the nasal airways. MRI provides an effective means to monitor changes in the nasal airways which occur as a result of pharmacological treatment.

Stabilization and Sensitization of Ferric Thiocyanate Colour for Determination of Trace Amount of Iron in Zinc Oxide and other Zinc Minerals

The effect of various ketones and ketonic mixtures on the stability and sensitivity of ferric thiocyanate colour in aqueous solution has been systematically studied. Maximum increase in intensity (about 2 times) and stability (more than 4 hours) of the coloured complex has been observed in aqueous solution containing a mixture of methyl ethyl ketone and acetone in the ratio from 2:1 to 1:2 and having an overall pH from 1.4 to 1.7. Below pH 1.4, the ferric thiocyanate colour separates out in the upper layer of the solution while its stability and intensity of colour decrease with the increase of pH above 2.7. Large amounts of zinc which interfere with the determination of iron by orthophenanthroline method do not have any adverse effect on the ferric thiocyanate colour. Based on these observations, a simple and sensitive procedure has been worked out for determination of small amounts of iron in zinc oxide and other zinc minerals.

Lens effect of the earth's ionosphere on radio waves reaching the moon

Radio waves from a distant source at grazing incidence on the Earth's atmosphere are focused at the Moon. The intensity distribution at the Moon's distance is calculated. The outer ionosphere focuses most strongly radio waves of a wavelength λ ≳ 1 m, giving a maximum increase in intensity of about 20. The E and F-layers give a smaller focusing effect.

Voltage Effects in Cholesteric Liquid Crystals

Abstract Liquid crystal mixtures were sandwiched between two transparent electrodes on glass and a direct or alternating potential was applied. The light scattering property of the liquid crystal changes upon application of voltage, the intensity varying from 1 to 10% of that scattered by a MgO diffuse surface. The maximum increase in intensity due to voltage was a factor of about six. The maximum wavelength shift was 40 nm to the blue by 80 V applied to a layer 10 μ thick. The response time varied from 0.03 to 0.5 sec.