bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simplifying EPID dosimetry for IMRT treatment verification
Authors: Pecharromán‐Gallego R. , Mans Anton , Sonke Jan‐Jakob , Stroom Joep C. , Olaciregui‐Ruiz Ígor , van Herk Marcel , Mijnheer Ben J. 
Published: February 2011

Purpose:Electronic portal imaging devices (EPIDs) are increasingly used for IMRT dose verification, both pretreatment andin vivo. In this study, an earlier developed backprojection model has been modified to avoid the need for patient‐specific transmission measurements and, consequently, leads to a faster procedure.Methods:Currently, the transmission, an essential ingredient of the backprojection model, is estimated from the ratio of EPID measurements with and without a phantom/patient in the beam. Thus, an additional irradiation to obtain “open images” under the same conditions as the actual phantom/patient irradiation is required. However, by calculating the transmission of the phantom/patient in the direction of the beam instead of using open images, this extra measurement can be avoided. This was achieved by using a model that includes the effect of beam hardening and off‐axis dependence of the EPID response on photon beam spectral changes. The parameters in the model were empirically obtained by performing EPID measurements using polystyrene slab phantoms of different thickness in 6, 10, and 18 MV photon beams. A theoretical analysis to verify the sensitivity of the model with patient thickness changes was performed. The new model was finally applied for the analysis of EPID dose verification measurements of step‐and‐shoot IMRT treatments of head and neck, lung, breast, cervix, prostate, and rectum patients. All measurements were carried out using Elekta SL20i linear accelerators equipped with a hydrogenated amorphous silicon EPID, and the IMRT plans were made usingPINNACLE software (Philips Medical Systems).Results:The results showed generally good agreement with the dose determined using the old model applying the measured transmission. The average differences between EPID‐basedin vivo dose at the isocenter determined using either the new model for transmission and its measured value were , , and for 47 patients treated with 6, 10, and 18 MV IMRT beams, respectively. For the same group of patients, the differences in mean analysis (3% maximum dose, 3 mm) were , , and , respectively. For a subgroup of 11 patients, pretreatment verification was also performed, showing similar dose differences at the isocenter: , , and , with somewhat lower mean difference values: , , and , respectively. Clinical implementation of the new model would save 450 h/yr spent in measurement of open images.Conclusions:It can be concluded that calculating instead of measuring the transmission leads to differences in the isocenter dose generally smaller than 2% (2.6% for 6 MV photon beams forin vivo dose) and yielded only slightly higher ‐evaluation parameter values in planes through the isocenter. Hence, the new model is suitable for clinical implementation and measurement of open images can be omitted.
Ultrasound internal tattooing
Authors: Couture Olivier , Faivre Magalie , Pannacci Nicolas , Babataheri Avin , Servois Vincent , Tabeling Patrick , Tanter Mickael 
Published: February 2011

Purpose:The ability of remotely tagging tissues in a controlled and three‐dimensional manner during preoperative imaging could greatly help surgeons to identify targets for resection. The authors' objective is to selectively and noninvasively deposit markers under image guidance for such internal tattooing.Methods:This study describes the production of new ultrasound‐inducible droplets carrying large payloads of fluorescent markers and thein vivo proof of concept of their remote and controlled deposition via focused ultrasound. The droplets are monodispersed multiple emulsions produced in a microfluidic system, consisting of aqueous fluorescein in perfluorocarbon in water. Their conversion (either by vaporization or cavitation) is performed remotely using a clinical ultrasonic imaging probe.Results:When submitted to 5 MHz imaging pulses, the droplets vaporizein vitro at 1.4 MPa peak‐negative pressure and eject their content. After several seconds, a brightly fluorescent spot (0.5 mm diameter) is observed at the focus of the transducer. Experiments in the chorioallantoique membrane of chicken eggs and chicken embryo demonstrate that the spot is stable and is easily seen by naked eye.Conclusions:These ultrasound‐inducible multiple emulsions could be used to deliver large amounts of contrast agents, chemotherapy, and genetic materialsin vivo using a conventional ultrasound scanner.
ACOUSTICAL STANDARDS NEWS
Authors: Blaeser Susan B. , Schomer Paul D. 
Published: February 2011

American National Standards (ANSI Standards) developed by Accredited Standards Committees S1, S2, S3, and S12 in the areas of acoustics, mechanical vibration and shock, bioacoustics, and noise, respectively, are published by the Acoustical Society of America (ASA). In addition to these standards, ASA publishes catalogs of Acoustical Standards, both National and International. To receive copies of the latest Standards Catalogs, please contact Susan B. Blaeser.
Comments are welcomed on all material in Acoustical Standards News.
This Acoustical Standards News section in JASA, as well as the National and International Catalogs of Acoustical Standards, and other information on the Standards Program of the Acoustical Society of America, are available via the ASA home page: http://asa.aip.org.
Kinematics of the Forcarei Synform (NW Iberian Variscan belt)
Authors: Fernández Francisco José , Díaz-García Florentino , Marquínez Jorge 
Published: February 2011

Abstract

The Forcarei Synform is a kilometric fold developed in the hinterland of the NW Iberian Variscan belt. A detailed analysis of the synform, based on quartz fabrics and kinematic markers, shows pervasively deformed rocks that have been continuously deformed during the last two main Variscan deformation phases (D
2
and D
3
).

Variscan D
2
minor structures related to the synform were formed under general non-coaxial flow and have a sub-horizontal maximum finite stretching toward the SSE. Later a coaxial D
3
produced a sub-vertical crenulation cleavage, and type 2 and 3 refolded folds figures at the meso- and micro-scale. Consequently, the strike of the foliations (S
2
and S
3
) become sub-parallel and lineation (L
2
and L
3
) are sub-horizontal. The geometry of the synform and the related structures can be interpreted in the context of D
3
. However the dominantly sinistral shear sense indicators, observed in both limbs of the synform (in map view), seem to be most probably developed during D
2
. A model is proposed involving the progressive clockwise rotation of a sub-horizontal shear, with general top-to-the-south sense, during the simultaneous development of shear zone and foliation in agreement with the kinematic indicators.
Polyphase deformation of the Variscan accretionary wedge: an example from the southern part of the Moravian Karst (Bohemian Massif, Czech Republic)
Authors: Rez Jiří , Melichar Rostislav , Kalvoda Jiří 
Published: February 2011

Abstract
The presence of two different coeval pre-flysch carbonate facies juxtaposed in numerous profiles in the southern part of the Moravian Karst proves that the Variscan nappe tectonics affected the pre-flysch basement of the main Culmian flysch nappes. Two main thrust events were recognized: (1) a ‘thin-skinned’ event, during which two sedimentary facies were juxtaposed along bedding sub-parallel thrusts, and (2) a ‘thick-skinned’ event, which generated younger thrusts oblique to bedding, involved crystalline rocks of the Brno Massif, and resulted in refolding of the older thrusts.
Kinematic evolution and strain simulation, based on cross-section restoration, of the Maiella Mountain: an analogue for oil fields in the Apennines (Italy)
Authors: Masini Massimiliano , Bigi Sabina , Poblet Josep , Bulnes Mayte , Cuia Raffaele Di , Casabianca Davide 
Published: February 2011

Abstract
Deformation predictive methods are useful for structural analysis from the scientific and industry point of view. We apply a strain simulation technique based on the inclusion of graphical strain markers in a cross-section, and subsequent cross-section restoration and numerical processing of strain markers, to the seismic-scale Maiella Mountain anticline (Central Apennines, Italy) considered a carbonate reservoir analogue for Apennines oil fields. The procedure followed involves field mapping and structural data collection, construction of cross-sections, sequential cross-section restoration, and application of the strain simulation technique. The cross-sections presented were constructed adopting one of the various structural interpretations proposed for this structure by different authors. According to this interpretation the Maiella Mountain structure resulted from Messinian–Early Pliocene extension and subsequent Late Pliocene shortening. According to our structural model the Maiella structure is a break-thrust fold and the comparison between the present-day and the restored cross-sections yields 1.3–4.6% of extension associated with two main normal faults and 21.5–22.1% and 2.5–3.4% of shortening due to a major thrust and folding respectively. The simulation of deformation distribution shows high deformation intensity in both limbs and low deformation in the anticline crest and part of the thrust footwall.
Kinematic retro-modelling of a cross-section through a thrust-and-fold belt: the Western Irish Namurian Basin
Authors: Tanner David C. , Bense Frithjof A. , Ertl Gabriele 
Published: February 2011

Abstract

The Western Irish Namurian Basin (WINB) developed into a fold-and-thrust belt at the front of the northward-propagating Variscan orogenic wedge. Part of this basin is well exposed along the coast of County Clare, Ireland. From a detailed study that used an integrated GPS mapping approach, we produced a
c
. 50 km long, balanced cross-section, parallel to the tectonic transport vector. We sequentially decompacted and retro-deformed the Namurian strata in 7 stages to evaluate the palinspastic situation of the basin and the amount of shortening. By using passive markers in the model and a highly-detailed timescale, we were able to determine that shortening of the WINB, from the onset of Central Clare Group sedimentation was 7.44% (or 4.07 km) of which shortening due to folding accounts for
c
. 2.64% (
c
. 1.37 km), and therefore
c
. 4.80% (
c
. 2.69 km) was solely because of thrusting. The rate of horizontal shortening ranges from 1–34 mm a
−1
; this is within typical orogenic values.
Kinematic evolution of the eastern Tethyan Himalaya: constraints from magnetic fabric and structural properties of the Triassic flysch in SE Tibet
Authors: Antolín Borja , Appel Erwin , Montomoli Chiara , Dunkl István , Ding Lin , Gloaguen Richard , El Bay Rachida 
Published: February 2011

Abstract

Anisotropy of magnetic susceptibility (AMS) combined with structural analysis are used in this work with the aim to characterize the tectonic evolution of the Triassic flysch within the eastern Tethyan Himalaya Thrust Belt in SE Tibet. The attitude of the magnetic foliation and lineation are concordant with the planar and linear structures of tectonic origin defined by the preferred orientation of the iron-bearing silicates. Two different tectonic domains can be defined: (a) the southern domain is controlled by the Eohimalayan tectonic foliation (S1) recorded in the magnetic foliation which trends east–west and dips to the north; (b) the northern domain is dominated by the Neohimalayan magnetic foliation with WNW–ESE strike and dips to the south opposite to the vergence of the main structures. A slightly prolate magnetic ellipsoid has been found in between the two domains recording the intersection of S1 and the subtle development of the S2 tectonic foliation. Hinterland propagation of the deformation lead to the Great Counter backthrust generation, pointed out by the SSW steeply plunging magnetic lineation. Furthermore different orientations of magnetic foliation may indicate an Early Miocene
c.
20° clockwise vertical-axis rotation.
Progressive deformation of a Coulomb thrust wedge: the eastern Fuegian Andes Thrust-Fold Belt
Authors: Carbonell Pablo J. Torres , Dimieri Luis V. , Olivero Eduardo B. 
Published: February 2011

Abstract

Time-calibrated balanced-cross sections of the eastern Fuegian Thrust–Fold Belt reveal many complex pro- and retro-vergent structures, rooted at the base of Cretaceous and within Paleocene rocks. These structures involve the unconformity-bounded syntectonic sequences of the Austral foreland basin, and accommodate a minimum shortening of
c
. 41.8 km. The complex kinematics of the thrust–fold belt are recorded by: (1) propagation of the basal décollement into the foreland, and forward-directed thrusting during the Ypresian; (2) out-of-sequence thrusting in the Lutetian; (3) subsidence and sedimentation from the Late Lutetian to the Oligocene; (4) backthrusting during the Oligocene; and (5) a renewed stage of forward-directed thrusting between the latest Oligocene and the Early Miocene, probably related to accretion below the sole fault in the hinterland. This thrust sequence is interpreted as the result of critical Coulomb wedge behaviour during the first stage of thrust–fold belt expansion, with accretion of new material that led to a taper decrease. The subsequent period of internal deformation corresponds to a subcritical stage, during which backthrusting accommodates significant shortening (
c
. 15%). After growth and taper increase, the last period of forward thrusting at the wedge's front marks the inception of a new critical stage.
Comparison of tectonic styles in the Mexican and Canadian Rocky Mountain Fold-Thrust Belt
Authors: Fitz-Diaz Elisa , Hudleston Peter , Tolson Gustavo 
Published: February 2011

Abstract
Despite the fact that most fold–thrust belts around the world share many features, successfully explained by the critical wedge model, the details of their geometric evolution and tectonic style development are poorly understood. In the classic section of the southern Canadian Rocky Mountains the dominant tectonic style consists of imbricate thrust sheets with relatively little internal deformation of the individual slices. In the Mexican fold–thrust Belt (Central Mexico), the age of deformation, the overall structural pattern and the total amount of shortening are similar, but the individual thrust sheets exhibit much more internal deformation as manifest by metre-scale buckle folds. One of the differences between these localities is the lateral variation of facies resulting in massive platform limestone separated by thinly-bedded basinal limestone in the Central Mexico section. Strain is concentrated toward the margins between platforms and basins. In Canada, thick platform carbonates form continuous resistant units across the Front Range. Possible reasons for the differences in tectonic style between the two sections include the dominant lithology, distribution of lithologies, taper angle of the tectonic wedges, amount of friction along the basal detachment and the degree of anisotropy of the basin facies rocks.
Contribution of Inherited Mutations in the BRCA2-Interacting Protein PALB2 to Familial Breast Cancer
Authors: Casadei Silvia , Norquist Barbara M. , Walsh Tom , Stray Sunday , Mandell Jessica B. , Lee Ming K. , Stamatoyannopoulos John A. , King Mary-Claire 
Published: February 2011

Abstract
Inherited mutations in the BRCA2-interacting protein PALB2 are known to be associated with increased risks of developing breast cancer. To evaluate the contribution of PALB2 to familial breast cancer in the United States, we sequenced the coding sequences and flanking regulatory regions of the gene from constitutional genomic DNA of 1,144 familial breast cancer patients with wild-type sequences at BRCA1 and BRCA2. Overall, 3.4% (33/972) of patients not selected by ancestry and 0% (0/172) of patients specifically of Ashkenazi Jewish ancestry were heterozygous for a nonsense, frameshift, or frameshift-associated splice mutation in PALB2. Mutations were detected in both male and female breast cancer patients. All mutations were individually rare: the 33 heterozygotes harbored 13 different mutations, 5 previously reported and 8 novel mutations. PALB2 heterozygotes were 4-fold more likely to have a male relative with breast cancer (P = 0.0003), 6-fold more likely to have a relative with pancreatic cancer (P = 0.002), and 1.3-fold more likely to have a relative with ovarian cancer (P = 0.18). Compared with their female relatives without mutations, increased risk of developing breast cancer for female PALB2 heterozygotes was 2.3-fold (95% CI: 1.5–4.2) by age 55 and 3.4-fold (95% CI: 2.4–5.9) by age 85. Loss of the wild-type PALB2 allele was observed in laser-dissected tumor specimens from heterozygous patients. Given this mutation prevalence and risk, consideration might be given to clinical testing of PALB2 by complete genomic sequencing for familial breast cancer patients with wild-type sequences at BRCA1 and BRCA2. Cancer Res; 71(6); 2222–9. ©2011 AACR.
A Study on the Reduction of Forecast Error Variance by Three Adaptive Observation Approaches for Tropical Cyclone Prediction
Authors: Qin Xiaohao , Mu Mu 
Published: February 2011

Abstract
Three adaptive approaches for tropical cyclone prediction are compared in this study: the conditional nonlinear optimal perturbation (CNOP) method, the first singular vector (FSV) method, and the ensemble transform Kalman filter (ETKF) method. These approaches are compared for 36-h forecasts of three northwest Pacific tropical cyclones (TCs): Matsa (2005), Nock-Ten (2004), and Morakot (2009). The sensitive regions identified by each method are obtained. The CNOPs form an annulus around the storm at the targeting time, the FSV targets areas north of the storm, and the ETKF closely targets the typhoon location itself. The sensitive results of both the CNOPs and FSV collocate well with the steering flow between the subtropical high and the TCs. Furthermore, the regions where the convection is strong are targeted by the CNOPs. Relatively speaking, the ETKF sensitive results reflect the large-scale flow.
To identify the most effective adaptive observational network, numerous probes or flights were tested arbitrarily for the ETKF method or according to the calculated sensitive regions of the CNOP and FSV methods. The results show that the sensitive regions identified by these three methods are more effective for adaptive observations than the other regions. In all three cases, the optimal adaptive observational network identified by the CNOP and ETKF methods results in similar forecast improvements in the verification region at the verification time, while the improvement using the FSV method is minor.
A Dynamical Interpretation of the Poleward Shift of the Jet Streams in Global Warming Scenarios
Authors: Rivière Gwendal 
Published: February 2011

Abstract
The role played by enhanced upper-tropospheric baroclinicity in the poleward shift of the jet streams in global warming scenarios is investigated. Major differences between the twentieth- and twenty-first-century simulations are first detailed using two coupled climate model outputs. There is a poleward shift of the eddy-driven jets, an increase in intensity and poleward shift of the storm tracks, a strengthening of the upper-tropospheric baroclinicity, and an increase in the eddy length scale. These properties are more obvious in the Southern Hemisphere. A strengthening of the poleward eddy momentum fluxes and a relative decrease in frequency of cyclonic wave breaking compared to anticyclonic wave breaking events is also observed.
Then, baroclinic instability in the three-level quasigeostrophic model is studied analytically and offers a simple explanation for the increased eddy spatial scale. It is shown that if the potential vorticity gradient changes its sign below the midlevel (i.e., if the critical level is located in the lower troposphere as in the real atmosphere), long and short wavelengths become respectively more and less unstable when the upper-tropospheric baroclinicity is increased.
Finally, a simple dry atmospheric general circulation model (GCM) is used to confirm the key role played by the upper-level baroclinicity by employing a normal-mode approach and long-term simulations forced by a temperature relaxation. The eddy length scale is shown to largely determine the nature of the breaking: long (short) wavelengths break more anticyclonically (cyclonically). When the upper-tropospheric baroclinicity is reinforced, long wavelengths become more unstable, break more strongly anticyclonically, and push the jet more poleward. Short wavelengths being less unstable, they are less efficient in pushing the jet equatorward. This provides an interpretation for the increased poleward eddy momentum fluxes and thus the poleward shift of the eddy-driven jets.
Mechanisms for Precipitation Variability of the Eastern Brazil/SACZ Convective Margin
Authors: Ma H.-Y. , Ji X. , Neelin J. D. , Mechoso C. R. 
Published: February 2011

Abstract
The present study examines the mechanisms for the connection between the precipitation variability in eastern Brazil and the South Atlantic convergence zone (SACZ) convective margin (eastern Brazil/SACZ convective margin) and the variability of low-level inflow on interannual time scales during austral summer. The authors' methodology is based on the analysis of observational datasets and simulations by the University of California, Los Angeles (UCLA) atmospheric general circulation model (AGCM) coupled to the Simplified Simple Biosphere Model.
It is demonstrated that the inflow variability is associated with the leading mode of wind variability over subtropical South America, and the connection is established through the mechanism of an analytic prototype for convective margin shifts proposed in previous studies. Over the eastern Brazil/SACZ convective margin, the weaker (stronger) convection tends to occur together with stronger (weaker) low-level inflows in reference to the mean easterly trades. By changing the “ventilation” effect, stronger (weaker) inflows with low moist static energy from the Atlantic Ocean suppress (promote) convection. The causal relationship is verified by AGCM mechanism-testing experiments performed in perpetual-February mode, in which low-level, nondivergent wind perturbations are imposed in a region overlapping eastern Brazil and the western Atlantic Ocean. With solely the imposed-wind perturbations acting on the moisture advection in the model equation, the AGCM can reproduce the precipitation variability in the eastern Brazil/SACZ convective margin. The capability of the AGCM in capturing such precipitation sensitivity to the low-level inflow variability also suggests that the mechanism can be applied to other regions of convective margins or to other time scales.