bluuebunny/crossref_metadata_2025 huggingface dataset:
A large candidate‐gene association study suggests genetic variants at IRF5 and PRDM1 to be associated with aggressive periodontitis
Authors: Schaefer Arne S. , Jochens Arne , Dommisch Henrik , Graetz Christian , Jockel‐Schneider Yvonne , Harks Inga , Staufenbiel Ingmar , Meyle Joerg , Eickholz Peter , Folwaczny Mathias , Laine Marja , Noack Barbara , Wijmenga Cisca , Lieb Wolfgang , Bruckmann Corinna , Schreiber Stefan , Jepsen Søren , Loos Bruno G.
Published: September 2014

Aim

Epidemiological and clinical studies indicated a relationship of periodontitis with rheumatoid arthritis (RA). We aimed to identify shared genetic susceptibility loci of RA and periodontitis.

Materials and Methods

Forty‐seven risk genes of genome‐wide significance of RA and SLE were genotyped in a German case–control sample of aggressive periodontitis (AgP), using Immunochip genotyping arrays (Illumina, 600 cases, 1440 controls) and Affymetrix 500 K Genotyping Arrays (280 cases and 983 controls). Significant associations were replicated in 168 Dutch AgP cases and 679 controls and adjusted for the confounders smoking and sex.

Results

Variants at IRF5 and PRDM1 showed association with AgP. Upon covariate adjustment for smoking and sex, the most strongly associated variant at IRF5 was the rare variant rs62481981 (ppooled = 0.0012, odds ratio [OR] = 3.1, 95% confidence interval [95% CI] = 1.6–6.1; 801 cases, 1476 controls).Within PRDM1 it was rs6923419 (ppooled = 0.004, OR = 0.7, 95% CI = 0.6–0.9; 833 cases, 1440 controls). The associations lost significance after correction for multiple testing in the replication. Both genes are implicated in beta‐interferon signalling and are also genome‐wide associated with SLE and inflammatory bowel disease.

Conclusion

The study gives no definite evidence for a pathogenic genetic link of periodontitis and RA but suggests IRF5 and PRDM1 as shared susceptibility factors.
Working memory and cognitive flexibility‐training for children with an autism spectrum disorder: a randomized controlled trial
Authors: de Vries Marieke , Prins Pier J.M. , Schmand Ben A. , Geurts Hilde M.
Published: September 2014

Background

People with autism spectrum disorders (ASDs) experience executive function (EF) deficits. There is an urgent need for effective interventions, but in spite of the increasing research focus on computerized cognitive training, this has not been studied in ASD. Hence, we investigated two EF training conditions in children with ASD.

Methods

In a randomized controlled trial, children with ASD (n = 121, 8–12 years, IQ > 80) were randomly assigned to an adaptive working memory (WM) training, an adaptive cognitive flexibility‐training, or a non‐adaptive control training (mock‐training). Braingame Brian, a computerized EF‐training with game‐elements, was used. Outcome measures (pretraining, post‐training, and 6‐week‐follow‐up) were near‐transfer to trained EFs, far‐transfer to other EFs (sustained attention and inhibition), and parent's ratings of daily life EFs, social behavior, attention deficit hyperactivity disorder (ADHD)‐behavior, and quality of life.

Results

Attrition‐rate was 26%. Children in all conditions who completed the training improved in WM, cognitive flexibility, attention, and on parent's ratings, but not in inhibition. There were no significant differential intervention effects, although children in the WM condition showed a trend toward improvement on near‐transfer WM and ADHD‐behavior, and children in the cognitive flexibility condition showed a trend toward improvement on near‐transfer flexibility.

Conclusion

Although children in the WM condition tended to improve more in WM and ADHD‐behavior, the lack of differential improvement on most outcome measures, the absence of a clear effect of the adaptive training compared to the mock‐training, and the high attrition rate suggest that the training in its present form is probably not suitable for children with ASD.
Evaluation of seasonal and daily changes of plasma thyroxine and cortisol levels in wild masu salmon Oncorhynchus masou, sampled by a Japanese fishing method
Authors: Munakata A. , Miura G. , Matsuda H.
Published: September 2014

A new fish sampling method was developed using a Japanese bait fishing rod (8–9 m carbon rod and a nylon line with a small fine wire single hook), which is considered to catch wild salmonid juveniles with low sampling stress. Using this method, seasonal and daily changes of plasma thyroxine (T4) and cortisol levels were examined in wild parr, pre‐smolts and smolts of masu salmon Oncorhynchus masou in contiguous locations in a coastal river (Kesen River; 44 km) in northern Honshu Island, Japan, overlapping the period of smoltification and seaward migration from August to March. Plasma T4 and cortisol were low in 0+ and 1+ year parr caught in August and September. In March, some yearling (1+ year) fish, which were judged as pre‐smolts, and smolts appeared mainly in mid and lower reaches, while parr (0+ and 1+ year parr) continued to appear in the upper and mid reaches. In March, 1+ year pre‐smolts and smolts showed high plasma T4 levels while the levels of 1+ year parr were low. During March 2008–2010, plasma T4 levels of 1+ year pre‐smolts and smolts had high levels from early to mid‐March, whereas plasma cortisol levels of 1+ year smolts were low in early March and increased towards mid‐March. Based on these data, plasma cortisol increases probably occur following the increases of plasma T4 levels to lead the 1+ year O. masou to the completion of smoltification and initiation of seaward migration.
Dynamic camouflage by Nassau groupers Epinephelus striatus on a Caribbean coral reef
Authors: Watson A. C. , Siemann L. A. , Hanlon R. T.
Published: September 2014

This field study describes the camouflage pattern repertoire, associated behaviours and speed of pattern change of Nassau groupers Epinephelus striatus at Little Cayman Island, British West Indies. Three basic camouflaged body patterns were observed under natural conditions and characterized quantitatively. The mean speed of pattern change across the entire body was 4·44 s (range = 0·97–9·87 s); the fastest pattern change as well as contrast change within a fixed pattern occurred within 1 s. Aside from apparent defensive camouflage, E. striatus used camouflage offensively to approach crustacean or fish prey, and three successful predation events were recorded. Although animal camouflage is a widespread tactic, dynamic camouflage is relatively uncommon and has been studied rarely in marine teleosts under natural conditions. The rapid changes observed in E. striatus suggest direct neural control of some skin colouration elements, and comparative studies of functional morphology and behaviour of colour change in other coral‐reef teleosts are likely to reveal new mechanisms and adaptations of dynamic colouration.
Seasonal changes in gene expression of corticoid receptors in anadromous and non‐anadromous strains of rainbow trout Oncorhynchus mykiss
Authors: Yada T. , Miyamoto K. , Miura G. , Munakata A.
Published: September 2014

To clarify the regulation of expression of corticoid receptor (CR) genes during period of parr–smolt transformation of salmonids, seasonal changes in mRNA levels of glucocorticoid receptor (GR)‐1, GR‐2 and mineralocorticoid receptor (MR) were examined in gill, leucocytes, spleen and brain of anadromous and non‐anadromous forms of Oncorhynchus mykiss. Increases in gill Na+, K+ ATPase activity, plasma thyroxine levels and hypo‐osmoregulatory ability assessed by 24 h seawater challenge test represented characteristics of smoltification in anadromous O. mykiss from May to June, whereas there was no apparent increase in the values of non‐anadromous O. mykiss. Plasma cortisol levels of anadromous O. mykiss were higher than levels of non‐anadromous O. mykiss from April to June. In gill of non‐anadromous O. mykiss, there were significant increases in mRNA levels of three types of CR in spring. Although there were significant seasonal variations of CR mRNA levels in gill of anadromous O. mykiss, they appear to be less clear than those variations in non‐anadromous O. mykiss. In anadromous O. mykiss, significant elevations in mRNA levels of the three types of CR were observed especially in the spleen. In both preoptic area and basal hypothalamus of the brain, there were tendencies to increase in CR mRNA levels from spring to summer in both anadromous and non‐anadromous O. mykiss. These results showed difference in regulation of CR gene expression between the two forms of O. mykiss for osmoregulatory, immune and central nervous systems.
Development of intestinal ion‐transporting mechanisms during smoltification and seawater acclimation in Atlantic salmon Salmo salar
Authors: Sundh H. , Nilsen T. O. , Lindström J. , Hasselberg‐Frank L. , Stefansson S. O. , McCormick S. D. , Sundell K.
Published: September 2014

This study investigated the expression of ion transporters involved in intestinal fluid absorption and presents evidence for developmental changes in abundance and tissue distribution of these transporters during smoltification and seawater (SW) acclimation of Atlantic salmon Salmo salar. Emphasis was placed on Na+, K+‐ATPase (NKA) and Na+, K+, Cl− co‐transporter (NKCC) isoforms, at both transcriptional and protein levels, together with transcription of chloride channel genes. The nka α1c was the dominant isoform at the transcript level in both proximal and distal intestines; also, it was the most abundant isoform expressed in the basolateral membrane of enterocytes in the proximal intestine. This isoform was also abundantly expressed in the distal intestine in the lower part of the mucosal folds. The protein expression of intestinal Nkaα1c increased during smoltification. Immunostaining was localized to the basal membrane of the enterocytes in freshwater (FW) fish, and re‐distributed to a lateral position after SW entry. Two other Nka isoforms, α1a and α1b, were expressed in the intestine but were not regulated to the same extent during smoltification and subsequent SW transfer. Their localization in the intestinal wall indicates a house‐keeping function in excitatory tissues. The absorptive form of the NKCC‐like isoform (sub‐apically located NKCC2 and/or Na+, Cl− co‐transporter) increased during smoltification and further after SW transfer. The cellular distribution changed from a diffuse expression in the sub‐apical regions during smoltification to clustering of the transporters closer to the apical membrane after entry to SW. Furthermore, transcript abundance indicates that the mechanisms necessary for exit of chloride ions across the basolateral membrane and into the lateral intercellular space are present in the form of one or more of three different chloride channels: cystic fibrosis transmembrane conductance regulator I and II and chloride channel 3.
Migratory patterns of hatchery and stream‐reared Atlantic salmon Salmo salar smolts in the Connecticut River, U.S.A.
Authors: McCormick S. D. , Haro A. , Lerner D. T. , O'Dea M. F. , Regish A. M.
Published: September 2014

The timing of downstream migration and detection rates of hatchery‐reared Atlantic salmon Salmo salar smolts and stream‐reared smolts (stocked 2 years earlier as fry) were examined in the Connecticut River (U.S.A.) using passive integrated transponder (PIT) tags implanted into fish and then detected at a downstream fish bypass collection facility at Turners Falls, MA (river length 192 km). In two successive years, hatchery‐reared smolts were released in mid‐April and early May at two sites: the West River (river length 241 km) or the Passumpsic (river length 450 km). Hatchery‐reared smolts released higher in the catchment arrived 7 to 14 days later and had significantly lower detection rates than smolts stocked lower in the catchment. Hatchery‐reared smolts released 3 weeks apart at the same location were detected downstream at similar times, indicating that early‐release smolts had a lower average speed after release and longer residence time. The size and gill Na+/K+‐ATPase (NKA) activity of smolts at the time of release were significantly greater for detected fish (those that survived and migrated) than for those that were not detected. Stream‐reared pre‐smolts (>11·5 cm) from four tributaries (length 261–551 km) were tagged in autumn and detected during smolt migration the following spring. Stream‐reared smolts higher in the catchment arrived later and had significantly lower detection rates. The results indicate that both hatchery and stream‐reared smolts from the upper catchment will arrive at the mouth of the river later and experience higher overall mortality than fish from lower reaches, and that both size and gill NKA activity are related to survival during downstream migration.
Personality and Behavior in Social Dilemmas: Testing the Situational Strength Hypothesis and the Role of Hypothetical Versus Real Incentives
Authors: Lozano José H.
Published: September 2014

Previous research aimed at testing the situational strength hypothesis suffers from serious limitations regarding the conceptualization of strength. In order to overcome these limitations, the present study attempts to test the situational strength hypothesis based on the operationalization of strength as reinforcement contingencies. One dispositional factor of proven effect on cooperative behavior, social value orientation (SVO), was used as a predictor of behavior in four social dilemmas with varying degree of situational strength. The moderating role of incentive condition (hypothetical vs. real) on the relationship between SVO and behavior was also tested. One hundred undergraduates were presented with the four social dilemmas and the Social Value Orientation Scale. One‐half of the sample played the social dilemmas using real incentives, whereas the other half used hypothetical incentives. Results supported the situational strength hypothesis in that no behavioral variability and no effect of SVO on behavior were found in the strongest situation. However, situational strength did not moderate the effect of SVO on behavior in situations where behavior showed variability. No moderating effect was found for incentive condition either. The implications of these results for personality theory and assessment are discussed.
ADP‐ribosylation factor 6 acts as an allosteric activator for the folded but not disordered cholera toxin A1 polypeptide
Authors: Banerjee Tuhina , Taylor Michael , Jobling Michael G. , Burress Helen , Yang ZhiJie , Serrano Albert , Holmes Randall K. , Tatulian Suren A. , Teter Ken
Published: September 2014

The catalytic A1 subunit of cholera toxin (CTA1) has a disordered structure at 37°C. An interaction with host factors must therefore place CTA1 in a folded conformation for the modification of its Gsα target which resides in a lipid raft environment. Host ADP‐ribosylation factors (ARFs) act as in vitro allosteric activators of CTA1, but the molecular events of this process are not fully characterized. Isotope‐edited Fourier transform infrared spectroscopy monitored ARF6‐induced structural changes to CTA1, which were correlated to changes in CTA1 activity. We found ARF6 prevents the thermal disordering of structured CTA1 and stimulates the activity of stabilized CTA1 over a range of temperatures. Yet ARF6 alone did not promote the refolding of disordered CTA1 to an active state. Instead, lipid rafts shifted disordered CTA1 to a folded conformation with a basal level of activity that could be further stimulated by ARF6. Thus, ARF alone is unable to activate disordered CTA1 at physiological temperature: additional host factors such as lipid rafts place CTA1 in the folded conformation required for its ARF‐mediated activation. Interaction with ARF is required for in vivo toxin activity, as enzymatically active CTA1 mutants that cannot be further stimulated by ARF6 fail to intoxicate cultured cells.
Paper oil and physical oil: has speculative pressure in oil futures increased volatility in spot oil prices?
Authors: Fowowe Babajide
Published: September 2014

A number of authors have attributed the high and volatile oil prices experienced since the turn of the 21st century to increased speculative activities arising from a relaxation of regulations in futures markets. This study examined the effects of speculative pressure on the volatility of spot oil prices. I constructed two measures of speculative pressure and modelled the volatility in oil returns by using the GARCH autoregressive conditional jump intensity model of Chan and Maheu, which models the effects of extreme news events in returns. Empirical results showed a significant positive coefficient for speculative pressure, implying that increased speculative pressure has contributed to volatile oil prices. This result is robust to different GARCH estimators and measures of speculative pressure.
Poster — Thur Eve — 26: Evaluation of lens dose from anterior electron beams: comparison of Pinnacle and Gafchromic EBT3 film
Authors: Sanier M , Wronski M , Yeboah C
Published: September 2014

The purpose of this work is twofold: 1) to measure dose profiles under lead shielding at the level of the lens for a range of clinical electron energies via film dosimetry; and, 2) to assess the validity of the Pinnacle treatment planning system (TPS) in calculating the penumbral doses under lead shielding with the heterogeneous electron algorithm. First, a film calibration curve that spanned the electron energies of interest, 6–18MeV, was created. Next, EBT3 film and lead shielding were incorporated into a solid water phantom with the film positioned 7mm below the lead and a variable thickness of bolus on top. This geometry was reproduced in the Pinnacle TPS and used to calculate dose profiles using the heterogeneous electron algorithm. The measured vs. calculated dose profiles were normalized to dmax in a homogeneous phantom with no lead shielding and compared. Pinnacle consistently overestimated the dose distal to the lead shielding with significant discrepancies occurring near the edge of the lead shield reaching 25% at the edge and 35% in the open field region. The film measurements showed that a minimum lead margin of 5mm extending beyond the diameter of the lens is required to adequately shield the lens to ≤10% of the dose at dmax. These measurements allow for a reasonable estimate of the dose to the lens from anterior electron beams. They also allow for clinicians to assess the extent of the lead margin required to reduce the lens dose to an acceptable amount prior to radiotherapy treatment.
Sci—Thur AM: YIS ‐ 03: irtGPUMCD: a new GPU‐calculated dosimetry code for 177Lu‐octreotate radionuclide therapy of neuroendocrine tumors
Authors: Montégiani Jean‐François , Gaudin Émilie , Jackson Price A. , Beauregard Jean‐Mathieu , Després Philippe
Published: September 2014

In peptide receptor radionuclide therapy (PRRT), huge inter‐patient variability in absorbed radiation doses per administered activity mandates the utilization of individualized dosimetry to evaluate therapeutic efficacy and toxicity. We created a reliable GPU‐calculated dosimetry code (irtGPUMCD) and assessed 177Lu‐octreotate renal dosimetry in eight patients (4 cycles of approximately 7.4 GBq).

irtGPUMCD was derived from a brachytherapy dosimetry code (bGPUMCD), which was adapted to 177Lu PRRT dosimetry. Serial quantitative single‐photon emission computed tomography (SPECT) images were obtained from three SPECT/CT acquisitions performed at 4, 24 and 72 hours after 177Lu‐octreotate administration, and registered with non‐rigid deformation of CT volumes, to obtain 177Lu‐octreotate 4D quantitative biodistribution. Local energy deposition from the β disintegrations was assumed. Using Monte Carlo gamma photon transportation, irtGPUMCD computed dose rate at each time point. Average kidney absorbed dose was obtained from 1‐cm3 VOI dose rate samples on each cortex, subjected to a biexponential curve fit. Integration of the latter time‐dose rate curve yielded the renal absorbed dose.

The mean renal dose per administered activity was 0.48 ± 0.13 Gy/GBq (range: 0.30–0.71 Gy/GBq). Comparison to another PRRT dosimetry code (VRAK: Voxelized Registration and Kinetics) showed fair accordance with irtGPUMCD (11.4 ± 6.8 %, range: 3.3–26.2%). These results suggest the possibility to use the irtGPUMCD code in order to personalize administered activity in PRRT. This could allow improving clinical outcomes by maximizing per‐cycle tumor doses, without exceeding the tolerable renal dose.
Poster — Thur Eve — 34: Estimation of true cumulative dose to the spinal canal in retreated spine SBRT
Authors: Lee YK , Thibault I , Sahgal A
Published: September 2014

Decisions on repeat spine SBRT are based on maximum dose constraints to the spinal cord region. The total dose that is assumed to be tolerable is typically the cumulative maximum biological effective dose (BED) calculated irrespective of location of this dose in the two plans. We explore the true spinal cord region BED taking into account BED position in the two plans.

Treatment plans of 16 repeat spine SBRT patients were retrospectively evaluated. TBEDmax and TBED0.35cc (sum from two plans) of spinal cord planning organ‐at‐risk volume (SCPRV) and thecal sac (TS) were calculated using α/β of 2Gy. To assess the ‘true’ dose, the first CT was deformably‐ or rigidly‐registered to the second CT. Image registration integrity was visually tested using the modified volumes from the first plan on the recent CT. Using the acquired registration parameters, the voxel‐based BED(VBEDmax, VBED0.35cc) from the two plans were added together and compared to the TBEDmax and TBED0.35cc.

The median(range) SCPRV TBEDmax was 98.7(72.5–135.7)Gy and VBEDmax was 76.6(57.3–129.6)Gy (p=0.01). The median(range) TS TBEDmax was 123.2(108.7–261.6)Gy compared to VBEDmax, which was 93.2(59.6–161.2)Gy (p=0.002). The median(range) SCPRV TBED0.35cc was 72.5(53.1–112.1)Gy and VBED0.35cc is 62.2(37.9–93.3)Gy (p=0.01). The median(range) TS TBED0.35cc was 80.3(64.7–120.6)Gy compared to VBED0.35cc was 68.2(45.2–92.1)Gy (p=0.01).

When taking location into account, true additive BED to the SCPRV/TS is lower than the current method of estimating BED for repeat spinal SBRT. By incorporating the dose location information, increase in dose to target volume adjacent to SC may be achievable with accurate and precise image registration.
Sci—Thur AM: YIS ‐ 09: Validation of a General Empirically‐Based Beam Model for kV X‐ray Sources
Authors: Poirier Y. , Sommerville M. , Johnstone C.D. , Gräfe J. , Nygren I. , Khan R. , Villareal‐Barajas J.E. , Jacso F. , Tambasco M.
Published: September 2014

Purpose:

To present an empirically‐based beam model for computing dose deposited by kilovoltage (kV) x‐rays and validate it for radiographic, CT, CBCT, superficial, and orthovoltage kV sources.

Method and Materials:

We modeled a wide variety of imaging (radiographic, CT, CBCT) and therapeutic (superficial, orthovoltage) kV x‐ray sources. The model characterizes spatial variations of the fluence and spectrum independently. The spectrum is derived by matching measured values of the half value layer (HVL) and nominal peak potential (kVp) to computationally‐derived spectra while the fluence is derived from in‐air relative dose measurements. This model relies only on empirical values and requires no knowledge of proprietary source specifications or other theoretical aspects of the kV x‐ray source.

To validate the model, we compared measured doses to values computed using our previously validated in‐house kV dose computation software, kVDoseCalc. The dose was measured in homogeneous and anthropomorphic phantoms using ionization chambers and LiF thermoluminescent detectors (TLDs), respectively.

Results:

The maximum difference between measured and computed dose measurements was within 2.6%, 3.6%, 2.0%, 4.8%, and 4.0% for the modeled radiographic, CT, CBCT, superficial, and the orthovoltage sources, respectively. In the anthropomorphic phantom, the computed CBCT dose generally agreed with TLD measurements, with an average difference and standard deviation ranging from 2.4 ± 6.0% to 5.7 ± 10.3% depending on the imaging technique. Most (42/62) measured TLD doses were within 10% of computed values.

Conclusions:

The proposed model can be used to accurately characterize a wide variety of kV x‐ray sources using only empirical values.
Poster — Thur Eve — 01: The effect of the number of projections on MTF and CNR in Compton scatter tomography
Authors: Chighvinadze T , Pistorius S
Published: September 2014

Purpose:

To investigate the dependence of the reconstructed image quality on the number of projections in multi‐projection Compton scatter tomography (MPCST). The conventional relationship between the projection number used for reconstruction and reconstructed image quality pertained to CT does not necessarily apply to MPCST, which can produce images from a single projection if the detectors have sufficiently high energy and spatial resolution.

Methods:

The electron density image was obtained using filtered‐backprojection of the scatter signal over circular arcs formed using Compton equation. The behavior of the reconstructed image quality as a function of the projection number was evaluated through analytical simulations and characterized by CNR and MTF.

Results:

The increase of the projection number improves the contrast with this dependence being a function of fluence. The number of projections required to approach the asymptotic maximum contrast decreases as the fluence increases. Increasing projection number increases the CNR but not spatial resolution.

Conclusions:

For MPCST using a 500eV energy resolution and a 2×2mm2 size detector, an adequate image quality can be obtained with a small number of projections provided the incident fluence is high enough. This is conceptually different from conventional CT where a minimum number of projections is required to obtain an adequate image quality. While increasing projection number, even for the lowest dose value, the CNR increases even though the number of photons per projection decreases. The spatial resolution of the image is improved by increasing the sampling within a projection rather than by increasing the number of projections.
Poster — Thur Eve — 11: Validation of the orthopedic metallic artifact reduction tool for CT simulations at the Ottawa Hospital Cancer Centre
Authors: Sutherland J , Foottit C
Published: September 2014

Metallic implants in patients can produce image artifacts in kilovoltage CT simulation images which can introduce noise and inaccuracies in CT number, affecting anatomical segmentation and dose distributions. The commercial orthopedic metal artifact reduction algorithm (O‐MAR) (Philips Healthcare System) was recently made available on CT simulation scanners at our institution. This study validated the clinical use of O‐MAR by investigating its effects on CT number and dose distributions.

O‐MAR corrected and uncorrected images were acquired with a Philips Brilliance Big Bore CT simulator of a cylindrical solid water phantom that contained various plugs (including metal) of known density. CT number accuracy was investigated by determining the mean and standard deviation in regions of interest (ROI) within each plug for uncorrected and O‐MAR corrected images and comparing with no‐metal image values. Dose distributions were calculated using the Monaco treatment planning system. Seven open fields were equally spaced about the phantom around a ROI near the center of the phantom. These were compared to a “correct” dose distribution calculated by overriding electron densities a no‐metal phantom image to produce an image containing metal but no artifacts.

An overall improvement in CT number and dose distribution accuracy was achieved by applying the O‐MAR correction. Mean CT numbers and standard deviations were found to be generally improved. Exceptions included lung equivalent media, which is consistent with vendor specified contraindications. Dose profiles were found to vary by ±4% between uncorrected or O‐MAR corrected images with O‐MAR producing doses closer to ground truth.
Poster — Thur Eve — 14: Improving Tissue Segmentation for Monte Carlo Dose Calculation using DECT
Authors: Di Salvio A. , Bedwani S. , Bouchard H. , Carrier J‐F.
Published: September 2014

Purpose:

To improve Monte Carlo dose calculation accuracy through a new tissue segmentation technique with dual energy CT (DECT).

Methods:

Electron density (ED) and effective atomic number (EAN) can be extracted directly from DECT data with a stoichiometric calibration method. Images are acquired with Monte Carlo CT projections using the user code egs_cbct and reconstructed using an FDK backprojection algorithm. Calibration is performed using projections of a numerical RMI phantom. A weighted parameter algorithm then uses both EAN and ED to assign materials to voxels from DECT simulated images. This new method is compared to a standard tissue characterization from single energy CT (SECT) data using a segmented calibrated Hounsfield unit (HU) to ED curve. Both methods are compared to the reference numerical head phantom. Monte Carlo simulations on uniform phantoms of different tissues using dosxyz_nrc show discrepancies in depth‐dose distributions.

Results:

Both SECT and DECT segmentation methods show similar performance assigning soft tissues. Performance is however improved with DECT in regions with higher density, such as bones, where it assigns materials correctly 8% more often than segmentation with SECT, considering the same set of tissues and simulated clinical CT images, i.e. including noise and reconstruction artifacts. Furthermore, Monte Carlo results indicate that kV photon beam depth‐dose distributions can double between two tissues of density higher than muscle.

Conclusions:

A direct acquisition of ED and the added information of EAN with DECT data improves tissue segmentation and increases the accuracy of Monte Carlo dose calculation in kV photon beams.
Extracting changes in air temperature using acoustic coda phase delays
Authors: Marcillo Omar , Arrowsmith Stephen , Whitaker Rod , Morton Emily , Scott Phillips W.
Published: September 2014

Blast waves produced by 60 high-explosive detonations were recorded at short distances (few hundreds of meters); the corresponding waveforms show charge-configuration independent coda-like features (i.e., similar shapes, amplitudes, and phases) lasting several seconds. These features are modeled as reflected and/or scattered waves by acoustic reflectors/scatters surrounding the explosions. Using explosion pairs, relative coda phase delays are extracted and modeled as changes in sound speed due to changes in air temperature. Measurements from nearby weather towers are used for validation.
Genome Sequence of Porphyromonas gingivalis Strain HG66 (DSM 28984)
Authors: Siddiqui Huma , Yoder-Himes Deborah Ruth , Mizgalska Danuta , Nguyen Ky-Anh , Potempa Jan , Olsen Ingar
Published: September 2014

Porphyromonas gingivalis
is considered a major etiologic agent in adult periodontitis. Gingipains are among its most important virulence factors, but their release is unique in strain HG66. We present the genome sequence of HG66 with a single contig of 2,441,680 bp and a G+C content of 48.1%.
An unusual cause of an ankle mass
Authors: Prinja Aditya , Roberts Catherine , Doherty Tom , Oddy Michael J
Published: September 2014

We report the case of a patient who presented with a 7-year history of a mass over the medial aspect of his right ankle, which had been gradually increasing in size. He had given up his occupation as a bus driver due to decreased movement of his ankle. An initial diagnosis of endemic syphilis was made after treponemal antibody and treponema pallidum particle agglutination tests were positive. However, following surgical debulking, cultures grewFusarium solaniand the diagnosis was changed to eumycetoma. He received prolonged treatment with antifungal agents and at 18 months follow-up remains well.
Preliminary observations on high energy phosphates and metabolic pathway and transporter potentials in extensor carpi radialis brevis and trapezius muscles of women with work-related myalgia
Authors: Green Howard J. , Ranney Don , Burnett Margaret , Galvin Patti , Kyle Natasha , Lounsbury David , Ouyang Jing , Smith Ian C. , Stewart Riley , Tick Heather , Tupling A. Russell
Published: September 2014

This study compared both the extensor carpi radialis brevis (ECRB) and the trapezius (TRAP) muscles of women with work-related myalgia (WRM) with healthy controls (CON) to determine whether abnormalities existed in cellular energy status and the potentials of the various metabolic pathways and segments involved in energy production and substrate transport. For both the ECRB (CON, n = 6–9; WRM, n = 13) and the TRAP (CON, n = 6–7; WRM, n = 10), no differences (P > 0.05) were found for the concentrations (in millimoles per kilogram of dry mass) of ATP, PCr, lactate, and glycogen. Similarly, with one exception, the maximal activities (in moles per milligram of protein per hour) of mitochondrial enzymes representative of the citric acid cycle (CAC), the electron transport chain (ETC), and β-oxidation, as well as the cytosolic enzymes involved in high energy phosphate transfer, glycogenolysis, glycolysis, lactate oxidation, and glucose phosphorylation were not different (P > 0.05). The glucose transporters GLUT1 and GLUT4, and the monocarboxylate transporters MCT1 and MCT4, were also normal in WRM. It is concluded that, in general, abnormalities in the resting energy and substrate state, the potential of the different metabolic pathways and segments, as well as the glucose and monocarboxylate transporters do not appear to be involved in the cellular pathophysiology of WRM.
Gravitational waves and perspectives for quantum gravity
Authors: Shapiro Ilya L. , Pelinson Ana M. , de O. Salles Filipe
Published: September 2014

Understanding the role of higher derivatives is probably one of the most relevant questions in quantum gravity theory. Already at the semiclassical level, when gravity is a classical background for quantum matter fields, the action of gravity should include fourth derivative terms to provide renormalizability in the vacuum sector. The same situation holds in the quantum theory of metric. At the same time, including the fourth derivative terms means the presence of massive ghosts, which are gauge-independent massive states with negative kinetic energy. At both classical and quantum level such ghosts violate stability and hence the theory becomes inconsistent. Several approaches to solve this contradiction were invented and we are proposing one more, which looks simpler than those what were considered before. We explore the dynamics of the gravitational waves on the background of classical solutions and give certain arguments that massive ghosts produce instability only when they are present as physical particles. At least on the cosmological background one can observe that if the initial frequency of the metric perturbations is much smaller than the mass of the ghost, no instabilities are present.
A "Resource Package"-Oriented Approach for Remote Sensing Analysis Modeling — Dust Storm Monitoring Model as Example
Authors: Zou Quan , Li Guoqing , Yu Wenyang , Cao Yang
Published: September 2014

Now, with the development of intelligent service technology, information provisioning models are changing from simple, single-type models to complex, on-demand models as required. Remote sensing analysis modeling often requires the use of multiple data sources, computer resources, tools, and models, and couples these resources into a workflow for global change research. Therefore, remote sensing analysis modeling research today faces a critical challenge: the registry, discovery, and allocation of modeling resources are complex, as they are heterogeneous and geographically distributed. This paper proposes a resource package-oriented approach that provides guidelines for remote sensing analysis modeling to increase model sharing and integrating. This unified wrapping approach can be used to make the management and use of existing resources becoming easy and reusable. Based on this description of construction method, different remote sensing analysis resources can be combined together on-demand. We developed a web environment to compose different remote sensing modeling resources as on-demand processing components, based on the existing workflow engineering, and use a dust storm monitoring model as an example. Comparative analyses are given to further explain the applications of this hierarchical construction method in the areas of the remote sensing analysis model.
PROPAGATION OF LOVE WAVE IN FIBER-REINFORCED MEDIUM OVER A NONHOMOGENEOUS HALF-SPACE
Authors: KUNDU SANTIMOY , GUPTA SHISHIR , MANNA SANTANU , DOLAI PRALAY
Published: September 2014

The present paper is devoted to study the Love wave propagation in a fiber-reinforced medium laying over a nonhomogeneous half-space. The upper layer is assumed as reinforced medium and we have taken exponential variation in both rigidity and density of lower half-space. As Mathematical tools the techniques of separation of variables and Whittaker function are applied to obtain the dispersion equation of Love wave in the assumed media. The dispersion equation has been investigated for three different cases. In a special case when both the media are homogeneous our computed equation coincides with the classical equation of Love wave. For graphical representation, we used MATLAB software to study the effects of reinforced parameters and inhomogeneity parameters. It has been observed that the phase velocity increases with the decreases of nondimensional wave number. We have also seen that the phase velocity decreases with the increase of reinforced parameters and inhomogeneity parameters. The results may be useful to understand the nature of seismic wave propagation in fiber reinforced medium.
Some congruences related to the q-Fermat quotients
Authors: Guo Victor J. W.
Published: September 2014

We give q-analogues of the following congruences by Z.-W. Sun: [Formula: see text] where p is an odd prime, [Formula: see text] are the Delannoy numbers, and [Formula: see text] are the harmonic numbers. We also prove that, for any positive integer m and prime p > m + 1, [Formula: see text] which is a multiple generalization of Kohnen's congruence. Furthermore, a q-analogue of this congruence is established.
Controllable Synthesis and Photocatalytic Properties of C-doped BiVO4 with Self-Heterostructure Under Different Light Sources
Authors: Wang Yong , Huang Jianfeng , Tan Guoqiang , Huang Jing , Zhang Lili
Published: September 2014

C -doped BiVO 4 with self-heterostructure were synthesized via a facile one-step microwave-hydrothermal route at different reaction temperatures and reaction times. The crystal structure, morphology and photophysical properties of the samples were characterized by X-ray diffraction (XRD), field-emission scanning electron microscope (FE-SEM) and UV-Vis techniques. The photocatalytic properties of the samples were evaluated by the decolorization of rhodamine B under ultraviolet light or simulated visible light irradiation. It was found that pure BiVO 4 polyhedrons had a monoclinic structure while C -doped BiVO 4 had self-heterostructure with both monoclinic and tetragonal phase. This mixed-phase structure exhibited higher activity than monoclinic structure under ultraviolet light irradiation while monoclinic C -doped BiVO 4 had better photocatalytic property under simulated visible light irradiation. The selectivity of the light source with different C -doped BiVO 4 self-heterostructures was also discussed in this work.
Luminescence Emission Mediated by Surface Plasmon in the Semiconductor Quantum Dots
Authors: Mao Huibing , Du Ling , Chen Ye , Li Bo , Huang Rong , Wang Jiqing
Published: September 2014

The luminescence of the hybrid CdSe / ZnS QDs– Ag nanocrystals has a weak blue shift in comparison with the luminescence of the pure quantum dots (QDs). The luminescence of the CdSe / ZnS QDs only has a single exponential decay process, and the decay rates are almost same for different emission wavelengths. The luminescence of the hybrid CdSe / ZnS QDs– Ag nanocrystals structure has two decay processes: The first is a fast decay process, and then there is a slow decay process with nearly the same decay rate of the pure QDs. The fast decay process is due to the surface plasmon coupling and the coupling rate depends on the energy difference between the confined exciton in the QDs and the resonance energy of the Ag plasmon.
Trends Over Time in the Risk of Stroke After an Incident Transient Ischemic Attack
Authors: Sundararajan Vijaya , Thrift Amanda G. , Phan Thanh G. , Choi Philip M. , Clissold Ben , Srikanth Velandai K.
Published: September 2014

Background and Purpose—

Long-term population trends in the early risk of stroke after transient ischemic attack (TIA) are unknown. We hypothesized that there has been an appreciable decline in the risk of stroke after TIA for the last decade.

Methods—

Population-level cohort study from Victoria, Australia (population 5.6 million), using linked data from hospitals, emergency departments, and death records (2001–2011), with a 2-year clearance period to define incident TIAs. Age-specific rates/1000, yearly incident rate ratios, and age–sex-adjusted risk of stroke after TIA were computed.

Results—

The mean age of 46 971 patients with TIA was 71 (SD=15), 52% women. In patients ≥65 years, annual TIA rates declined between 2001 and 2011 from 5.8 to 4.8/1000 (men) and from 5.3 to 4.2/1000 (women). Yearly incident rate ratios were 0.97 (95% confidence interval, 0.96–0.98) in men and 0.97 (95% confidence interval, 0.97–0.98) in women. Overall, the 90-day stroke risk was 3.1%. Age–sex-adjusted risk of stroke at 90 days after a TIA decreased by 3% per year (odds ratio for the effect of year, 0.97; 95% confidence interval, 0.95–0.99). Male sex, direct discharge from emergency departments, public hospital care, stroke unit care, and absence of vascular risk factors were associated with a downward yearly trend of stroke within 90 days of TIA.

Conclusions—

Over the last 10 years, there has been a measurable decline in the 90-day risk of stroke after an incident TIA and overall decline in rates of TIA in Victoria, Australia. These trends may reflect improved primary and secondary prevention efforts for the last decade.
Reconsidering the “Acculturation Gap” Narrative Through an Analysis of Parent–Adolescent Acculturation Differences in Mexican American Families
Authors: Nieri Tanya , Grindal Matthew , Adams Michele A. , Cookston Jeffrey T. , Fabricius William V. , Parke Ross D. , Saenz Delia S.
Published: September 2014

Using a sample of 193 Mexican American adolescents ( M age at Wave 1 = 14 years) and three waves of data over 2 years, this study longitudinally examined the effects of parent–youth acculturation differences, relative to no differences, on parent–adolescent relationship quality and youth problem behavior. We examined parent–youth differences in overall acculturation, Mexican acculturation, and American acculturation. We differentiated between cases in which the adolescent was more acculturated than the parent and cases in which the parent was more acculturated than the adolescent. Adolescents were more commonly similar to their parents than different. Where differences existed, adolescents were not uniformly more American than their parents, no type of difference was associated with parent–adolescent relationship quality, and no type of difference in overall acculturation was associated with youth problem behavior. One type of difference by dimension (adolescent had less Mexican acculturation than mother) was associated with less risk of problem behavior.
Effect of a physical education-based stretching programme on sit-and-reach score and its posterior reduction in elementary schoolchildren
Authors: Merino-Marban Rafael , Mayorga-Vega Daniel , Fernandez-Rodriguez Emilio , Estrada Francisco Vera , Viciana Jesús
Published: September 2014

The purpose of this study was to examine the effects of a 1-minute stretching programme and 5 weeks of detraining on sit-and-reach score among schoolchildren aged 5–6 years in a physical education setting. Forty-five schoolchildren 5–6 years old from two classes were clustered randomly assigned to an experimental group ( n = 23) or a control group ( n = 22). During the physical education classes, the students of the experimental group performed a 1-minute stretching programme twice a week for 8 weeks. Subsequently, these participants underwent a 5-week detraining period. The classic sit-and-reach test was performed at the beginning and at the end of the development programme, as well as at the end of the detraining period. The results of the two-way ANOVA showed that the intervention programme increased significantly the students’ sit-and-reach scores (  p < 0.001). However, after 5 weeks of detraining, children’s flexibility reverted back to the baseline levels (  p > 0.05). Although an only 1-minute stretching programme seems to develop the schoolchildren’s flexibility, after the 5-week detraining period students’ score reverts back to its initial level. This knowledge could help physical education teachers to design programmes that permit students to increase and maintain flexibility levels along the entire academic year.
Community Members’ Assessment of the Physical Activity Environments in Their Neighborhood Parks
Authors: Greer Anna Elizabeth , Marcello Rich , Graveline Rochelle
Published: September 2014

Objective. This study engaged community members to describe physical activity (PA) environments in parks and to examine if the PA environment in parks was related to the economic characteristics of households near parks. Method. Twenty-four Bridgeport, adult residents examined the PA environments in 21 Bridgeport, Connecticut, parks using the Community Stakeholder Park Audit Tool (CPAT) during the summer, 2013. ESRI’s Geographical Information System was used to identify the economic characteristics (i.e., median household income, percentage of households below the poverty line; from 2010 Census data) of households within 0.5 miles of a park. Descriptive and inferential statistics were used to analyze CPAT data. Results. A negative association was identified between the parks’ PA area and safety scores ( p = .012). Positive associations were identified between the parks’ PA area and amenities scores ( p < .001), access and amenities scores ( p = .006), and park safety concern and surrounding safety concern scores ( p < .001). There were no significant associations between park environment indices and the economic characteristics of households less than 0.5 miles from parks. Community members recommended several strategies to enhance PA environments in parks. Conclusions. The findings highlight the utility of CPAT for enabling community members identify opportunities to enhance PA environments in parks.