bluuebunny/crossref_metadata_2025_split huggingface dataset:
TH‐C‐301‐03: Utilization of MOSFET Dosimeters for Clinical Measurements in Radiology
Authors: Hintenlang D 
Published: November 2011

Purpose: MOSFET dosimeters are attractive dosimeters for a number of applications in diagnostic radiology due primarily to their small size and the ability to rapidly read the resulting x‐ray dose. It is important to understand the characteristics of these unique dosimeters in order to accurately interpret the output and successful predict patient dose.Methods: The characteristics of MOSFET dosimeters have been evaluated for a variety of diagnostic radiology applications. Specific tests were designed to evaluate important MOSFET responses over the x‐ray energy range of interest (20–150 keV). Responses of these devices have been characterized for energy response, angular dependence, temperature, fading, dose linearity and sensitivity.Results: MOSFET dosimeters are available in configurations having differing physical geometry, sizes, sensitivity and absorbed dose limited usefulness. These dosimeters typically exhibit good angular response around their longitudinal axis and the variation of response as a function of ambient temperature is small. Some of the parameters that need to be carefully considered include the variation in energy response and sensitivity limits inherent to MOSFET dosimeters. These dosimeters require an accurate calibration exposure (or dose) to mV calibration for the energy source corresponding to the intended application. For example, a separate calibration needs to be developed for mammography applications for different accelerating potential and target/filter combinations. The overall sensitivity of these dosimeters can be a limitation for accurate dose assessment at clinical exposure levels. Examples of MOSFET applications for clinical dosimetry, when integrated with anthropomorphic phantoms are presented for mammography, radiography and computed tomography examples.Conclusions : MOSFET dosimeters can provide a convenient dosimetry tool capable of simultaneous measurement for multiple dosimetry points, usually up to twenty individual locations. Careful energy calibration is essential to accurate dosimetry interpretation and care should be exercised to ensure that exposures are large enough to provide consistent radiation measurement.
TH‐C‐301‐04: Optically Stimulated Luminescent Dosimeters (OSLDs) and Thermoluminescence Dosimeters (TLDs)
Authors: Lu Z , Feng W , Yahnke C 
Published: November 2011

In this presentation, we will focus on two types of scintillators with trapping of excited electrons for dosimetric purposes. The conventional type is thermoluminescent dosimeter (TLDs), in which the electrons are trapped in excited status when exposed to ionizing radiation, and when later heated, the trapped electrons then fall to their ground state with light emission. By measuring the light emitted one can determine the radiation dose previously received. In recent years, optically stimulated luminescent (OSL) dosimeter has grown to be an alternative to TLDs due to the convenience of its usage. The OSL dosimeters also trap excited electrons when exposed to ionizing radiation. Instead of heat, stimulation light is used to release the stored energy in OSL dosimeters. The intensity of the emitted light depends on the dose absorbed by the OSL dosimeters and the intensity of the stimulation light. Its sensitivity, reproducibility, precision in responding to accumulative dose and its energy dependence have also been studied in order to demonstrate its potential. We will discuss both TLDs and OSLDs with regards to their dosimetric properties and applications in radiation therapy dosimetry as well as in diagnostic imaging dose monitoring.Learning Objectives:1. To understand the basic principles of optically stimulated luminescent (OSL) and thermoluminescence (TLD) dosimeters.2. To learn their physical properties and characteristics as dosimeters.3. To compare the applications of OSL and TLD dosimeters in radiation therapy dosimetery as well as in diagnostic imaging dose monitoring.
TH‐E‐224‐01: Role of Medical Physics in Federal and State Government
Authors: Fletcher D , Rodgers R , Suleiman O , Keith S , Gilley D 
Published: November 2011

This session is designed be used as a forum to discuss the role medical physics has within the federal and state governments. Medical Physicists are involved with everything from clinical practice to regulatory jobs in state and federal agencies. There are also many jobs to include support of the Indian Health Service, program management jobs, and federal and state emergency preparedness groups as well as a variety of others. This session is designed to be an effective venue to identify specific concerns and challenges within the public sector. Speakers from DoD, FDA, CDC, and the State of Florida will provide short presentations followed by an open forum session.Learning objectives:1. To provide a venue in which physicists working in the public sector can interface and discuss specific issues related to supporting the federal and state governments.2. To provide a venue to for educating medical physicists of additional resources available within the federal and state systems.3. To provide a venue for medical physicists to voice specific concerns with federal or state programs where medical physics should be involved and/or be more effective.
TH‐E‐BRB‐05: Modeling the Correlation Between OAR Dose Sparing and Patientˈs Anatomy in Head and Neck IMRT
Authors: Yuan L , Ge Y , Li T , Zhu X , Yin F , Wu Q 
Published: November 2011

Purpose: To summarize the knowledge of the dependence of organ‐at‐risk (OAR) dose‐volume distribution on patientˈs anatomy by machine learning techniques from a database of previous expert plans. Methods: 35 head‐and‐ neck IMRT plans were studied retrospectively. The OAR‐PTV geometry was modeled by the distance‐to‐target histogram (DTH). Principal Component Analysis (PCA) was applied to DVH and DTH to capture their salient features. The PCs of the DVH and DTH were then mapped to the parameter space of patient anatomy and dose distribution using correlation analysis. A polynomial model of the correlation between OAR DVH and patient anatomy was constructed and trained by a stepwise regression method. Two major OARs, the right/left parotids, were modeled in the regression analysis. Results: (1) PCA characterizes two salient features of the DTH and DVH, the first as the mean of the histogram, the second as the average gradient of the histogram within a range. (2) The regression analysis shows that the main factors contributing to the first component of the principal component score (PC1) of OAR DVH are the PC1 of DTH and the fractional volume in the overlap region, and the main factor affecting the PC2 of OAR DVH is the PC2 of DTH. (3) In terms of patient anatomy and dose‐volume distribution parameters, these correlations indicate the influences of the mean and gradient of DTH on the mean and gradient of DVH by the patient plan. In addition, the fractional volume outside treatment field with co‐planar beam setting also plays a role in determining OAR DVH. The determination coefficients by the polynomial models are: R,2</sup>=0.89 and R,2</sup>=0.47 for PC1 and PC2 of right parotid, respectively; R,2</sup>=0.64 and R,2</sup>=0.41 for PC1 and PC2 of left parotid, respectively. Conclusions: The model learned from the database quantifies the influence of geometrical complexity on the OAR dose sparing.Duke University has a master reaserch agreement with VARIAN Medical Systems, Inc..
Anatomy and photochemical behaviour of Mediterranean Cistus incanus winter leaves under natural outdoor and warmer indoor conditions
Authors: De Micco Veronica , Arena Carmen , Vitale Luca , Aronne Giovanna , Virzo De Santo Amalia 
Published: November 2011

Plants in Mediterranean environments can adopt photoprotective mechanisms to cope with winter temperatures, thus avoiding photoinhibition. An increase in global temperature is expected in the future as a consequence of climate change. The aims of this work were (i) to analyse anatomy and photochemical activity in winter leaves of Cistus incanus L., to identify characters having a potential role in photoprotection under natural winter conditions, and (ii) to evaluate the effect of higher temperature on such traits. Leaves from plants grown in a greenhouse (indoor) were compared with those from plants grown outdoors on the basis of anatomical and photochemical traits, including indexes evaluating the exposure of chloroplasts at the cell surface. Leaves developed outdoors were characterized by anatomical traits related to the optimization of light harvesting and to gas-exchange control. Such traits were accompanied by a higher pigment content and an increase in the thermal dissipation of excess absorbed light. Indoor leaves showed physiological and morphoanatomical adjustments addressed to invest more of absorbed light in photochemistry. Overall, our analysis showed that (i) photoprotection in C. incanus relies on adaptive traits at both the morphoanatomical and physiological level and (ii) C. incanus leaves seem to be able to acclimatize to warmer winters.
Flow of S-matrix poles for elementary quantum potentials1This research was supported in part by an NSERC Undergraduate Summer Research Award (SGN) and an NSERC Discovery Grant (MAW).
Authors: Belchev B. , Neale S.G. , Walton M.A. 
Published: November 2011

The poles of the quantum scattering matrix (S-matrix) in the complex momentum plane have been studied extensively. Bound states give rise to S-matrix poles, and other poles correspond to non-normalizable antibound, resonance, and antiresonance states. They describe important physics but their locations can be difficult to determine. In pioneering work, Nussenzveig (Nucl. Phys. 11, 499 (1959)) performed the analysis for a square well (wall), and plotted the flow of the poles as the potential depth (height) varied. More than fifty years later, however, little has been done in the way of direct generalization of those results. We point out that today we can find such poles easily and efficiently using numerical techniques and widely available software. We study the poles of the scattering matrix for the simplest piecewise flat potentials, with one and two adjacent (nonzero) pieces. For the finite well (wall) the flow of the poles as a function of the depth (height) recovers the results of Nussenzveig. We then analyze the flow for a potential with two independent parts that can be attractive or repulsive, the two-piece potential. These examples provide some insight into the complicated behavior of the resonance, antiresonance, and antibound poles.
Asymptotically anti-de Sitter magnetic branes in (n + 1)-dimensional dilaton gravity
Authors: Dehghani M.H. , Bazrafshan A. 
Published: November 2011

We present a new class of asymptotically anti-de Sitter (AdS) magnetic solutions in (n + 1)-dimensional dilaton gravity in the presence of an appropriate combination of three Liouville-type potentials. This class of solutions is asymptotically AdS in six and higher dimensions and yields a space–time with a longitudinal magnetic field generated by a static brane. These solutions have no curvature singularity and no horizons but have a conic geometry with a deficit angle. We find that the brane tension depends on the dilaton field and approaches a constant as the coupling constant of the dilaton field goes to infinity. We generalized this class of solutions to the case of spinning magnetic solutions and find that, when one or more rotation parameters are nonzero, the brane has a net electric charge that is proportional to the magnitude of the rotation parameters. Finally, we used the counterterm method inspired by AdS – conformal field theory correspondence and computed the conserved quantities of these space–times. We found that the conserved quantities do not depend on the dilaton field, which is evident from the fact that the dilaton field vanishes on the boundary at infinity.
The Impact of Obesity on the Rise in Esophageal Adenocarcinoma Incidence: Estimates from a Disease Simulation Model
Authors: Kong Chung Yin , Nattinger Kevin J. , Hayeck Tristan J. , Omer Zehra B. , Wang Y. Claire , Spechler Stuart J. , McMahon Pamela M. , Gazelle G. Scott , Hur Chin 
Published: November 2011

Abstract
Background: The United States has experienced an alarming and unexplained increase in the incidence of esophageal adenocarcinoma (EAC) since the 1970s. A concurrent increase in obesity has led some to suggest a relationship between the two trends. We explore the extent of this relationship.
Methods: Using a previously validated disease simulation model of white males in the United States, we estimated EAC incidence 1973 to 2005 given constant obesity prevalence and low population progression rates consistent with the early 1970s. Introducing only the observed, rising obesity prevalence, we calculated the incremental incidence caused by obesity. We compared these with EAC incidence data from the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) registry to determine obesity's contribution to the rise therein. Incidences were converted to absolute numbers of cases using U.S. population data.
Results: Using constant obesity prevalence, we projected a total of 30,555 EAC cases cumulatively over 1973 to 2005 and 1,151 in 2005 alone. Incorporating the observed obesity trend resulted in 35,767 cumulative EACs and 1,608 in 2005. Estimates derived from SEER data showed 111,223 cumulative and 7,173 cases in 2005. We conclude that the rise in obesity accounted for 6.5% of the increase in EAC cases that occurred from 1973 to 2005 and 7.6% in the year 2005.
Conclusion: Using published OR for EAC among obese individuals, we found that only a small percentage of the rise in EAC incidence is attributable to secular trends in obesity.
Impact: Other factors, alone and in combination, should be explored as causes of the EAC epidemic. Cancer Epidemiol Biomarkers Prev; 20(11); 2450–6. ©2011 AACR.
Case–Control Study of the Metabolic Syndrome and Metabolic Risk Factors for Endometrial Cancer
Authors: Friedenreich Christine M. , Biel Rita K. , Lau David C.W. , Csizmadi Ilona , Courneya Kerry S. , Magliocco Anthony M. , Yasui Yutaka , Cook Linda S. 
Published: November 2011

Abstract
Background: Metabolic syndrome may predict endometrial cancer risk better than diabetes, hypertension, dyslipidemia, dysglycemia, or weight alone, but few studies have examined this issue.
Methods: We conducted a population-based case–control study in Alberta, Canada (2002–2006) that included 515 incident endometrial cancer cases and 962 frequency age-matched controls. Data were collected through in-person interviews, anthropometric measurements, and 8-hour fasting bloods drawn either pre- or postsurgery. Bloods were analyzed using quantitative colorimetric or absorbance-based assays (ELISA), specific to metabolic syndrome markers. Metabolic syndrome was defined using harmonized guidelines requiring presence of ≥3 of the following risk factors: waist circumference ≥88 cm, triglycerides ≥150 mg/dL, high-density lipoprotein cholesterol &lt;50 mg/dL, treatment of previously diagnosed hypertension, and fasting blood glucose ≥100 mg/dL. OR and 95% CIs for endometrial cancer risk with presence of metabolic syndrome and individual metabolic syndrome components were estimated using logistic regression analysis.
Results: Metabolic syndrome was significantly more prevalent among cases (62%) than controls (38%). A statistically significant increased risk for endometrial cancer was observed for metabolic syndrome (OR = 1.53; 95% CI: 1.17–2.00), as well as for some of the individual components of metabolic syndrome including waist circumference ≥88 cm (OR = 1.57; 95% CI: 1.18–2.08), hypertension (OR = 1.57; 95% CI: 1.18–2.09), and fasting blood glucose ≥100 mg/dL (OR = 1.31; 95% CI: 1.03–1.67). Some evidence for effect modification by menopausal status and body mass index was also found.
Conclusion: Metabolic syndrome is clearly associated with increased endometrial cancer risk.
Impact: Targeting the entire metabolic syndrome may optimize endometrial cancer risk reduction. Cancer Epidemiol Biomarkers Prev; 20(11); 2384–95. ©2011 AACR.
A Virtual Reality Version of the Trier Social Stress Test: A Pilot Study
Authors: Wallergård Mattias , Jönsson Peter , Johansson Gerd , Karlson Björn 
Published: November 2011

One of the most common methods of inducing stress in the laboratory in order to examine the stress response in healthy and clinical populations is the Trier Social Stress Test (TSST). Briefly, the participant is asked to deliver a speech and to perform an arithmetic task in front of an evaluating committee. The committee, consisting of three trained actors, does not respond emotionally during the test, which makes the situation very stressful for the participant. One disadvantage of the TSST is that it can be difficult to hold the experimental conditions constant. In particular, it may be difficult for actors to hold their acting constant across all sessions. Furthermore, there are several practical problems and costs associated with hiring professional actors. A computerized version of the TSST using virtual humans could be a way to avoid these problems provided that it is able to induce a stress response similar to the one of the original TSST. The purpose of the present pilot study was therefore to investigate the stress response to a virtual reality (VR) version of the TSST visualized using an immersive VR system (VR-TSST).Seven healthy males with an average age of 24 years (range: 23–26 years) performed the VR-TSST. This included delivering a speech and performing an arithmetic task in front of an evaluating committee consisting of three virtual humans. The VR equipment was a CAVE equipped with stereoscopy and head tracking. ECG and respiration were recorded as well as the participant's behavior and comments. Afterward, a semi-structured interview was carried out.In general, the subjective and physiological data from the experiment indicated that the VR version of the TSST induced a stress response in the seven participants. In particular, the peak increase in heart rate was close to rates observed in studies using the traditional TSST with real actors. These results suggest that virtual humans visualized with an immersive VR system can be used to induce stress under laboratory conditions.
The Birth of a Custom: Nomads, Sharīa Courts and Established Practices in the Tashkent Province, ca. 1868-1919
Authors: Sartori Paolo 
Published: November 2011

AbstractIn colonial Central Asia qādīs played a key role in establishing customary legal practices. In adjudicating claims of horse theft, qādīs operating in the Tashkent province under Russian rule had recourse to customary rules of evidence known in the local Kazakh communities. If a qādī ascertained that an animal was not stolen, but had been acquired from a third party by a bone fide purchaser, he routinely used a probative procedure unknown of in the Central Asian judicial manuals of the 19th and early 20th centuries. Based on an examination of sharī'a court registers from the Tashkent province, Bukharan shurūt works and unpublished archival material, I argue that the establishment of Russian rule in the region and the introduction of triennial elections for choosing judges made it necessary for each qādī to meet the demands of the community that had elected him, thereby encouraging him to confer shar'ī legitimacy on local legal practices.
Wahhābī Legal Theory as Reflected in Modern Official Saudi Fatwās: Ijtihād, Taqlīd, Sources, and Methodology
Authors: al-Atawneh Muhammad 
Published: November 2011

AbstractThe purpose of this essay is to open a window into Wahhābī legal theory as reflected in modern-day official Saudi fatwās. Discussion includes ijtihād, taqlīd, madhhab affiliation, sources and methodology. Emphasis is placed on continuity and change in light of the country's official school of law, the Hanbalī madhhab. I show that, in principle, modern-day Wahhābīs remain faithful to the tenets of Hanbalism by privileging adherence to the text and to transmitted tradition (naql) over reason ('aql). It is evident, however, that Wahhābīs now go beyond Hanbalism, drawing their legal inspiration not only from their Hanbalī intellectual forebears, but also from a wide array of non-Hanbalī traditions and scholars. Moreover, Wahhābī legal theory today breaks from classical Hanbalī legal epistemology as presented by Ibn Taymiyya (d. 1328) and his disciples. This is manifested especially in: (1) limiting the practice of ijtihād to qualified scholars; (2) endorsing taqlīd for those unqualified to investigate the sacred texts; and (3) identifying public interest (maslaha) in accordance with the five objectives (maqāsid) of the Sharī'a.
Ionic Composition and Ion Provisioning in Marsupial Fluid of Terrestrial Isopods (Isopoda, Oniscidea)
Authors: Yoshizawa Anne , Wright Jonathan C. 
Published: November 2011

Abstract
The marsupium of the primarily terrestrial isopod sub-order Oniscidea is modified from the basal marine design and represents one of the key evolutionary innovations enabling the invasion of land habitats. In the Ligiidae, the marsupial chamber is provisioned with water from the external environment via a capillary channel formed from the apposed 6th and 7th pereiopods. The other oniscidean families possess a 'closed' marsupium, isolated from the pleural water-conducting system and provisioned with water and ions by sternal cotyledons. How these different modes of fluid provisioning influence the ionic composition of marsupial fluid and its osmotic and ionic relationship to the haemolymph remains essentially unstudied. We analysed the ionic composition (Na+, K+, Ca2+, Cl–, pH) of marsupial fluid and haemolymph in 4 species of Oniscidea: Ligia occidentalis (Ligiidae), Ligidium lapetum (Ligiidae), Alloniscus perconvexus (Alloniscidae), and Armadillidium vulgare (Armadillidiidae). In all four species, ion concentrations show a broad similarity between marsupial fluid and haemolymph, but with elevated potassium concentrations in the 'closed'-marsupium species. The sternal integument of Armadillidium vulgare is permeable to inulin and the volume of the combined marsupial fluid and haemolymph is not significantly enlarged compared to the haemolymph of non-gravid females. Accordingly, the 'closed' marsupium of A. vulgare can be viewed as a functional subdivision of the haemolymph space. In Ligidium lapetum, marsupial water is derived from external freshwater sources, but marsupial fluid [Na+] and [Cl–]are actually significantly higher than haemolymph values. This species thus possesses an effective means of ion provisioning, paralleling that seen in the 'closed' marsupial species.
Growth and Reproduction Data of Plesionika Narval (Decapoda, Caridea, Pandalidae) Off the Island of Ustica (Southern Tyrrhenian Sea)
Authors: Arculeo M. , Brutto S. Lo 
Published: November 2011

AbstractWe here report some data on the biology and population structure of Plesionika narval (Fabricius, 1787) captured along the coast of the island of Ustica in the southern Tyrrhenian Sea. Specimens were collected monthly from January to October 2000 using commercial traps at depths ranging from 15 to 100 metres. The carapace length (CL) of females ranged between 7.0 and 26.0 mm, and between 7.0 and 17.0 mm for males. Three modes were identified in the cumulative frequency distribution for females but only two for males. In females, the third modal value was observed only at the deeper sample sites. The Von Bertalanffy growth parameters and performance index &phiv; were K = 0.65 y–1, CL∞ = 27.4 mm CL and &phiv; = 2.62 for females, and K = 0.71 y–1, CL∞ = 17.8 mm CL and &phiv; = 2.28 for males. Ovigerous females were found during the entire period of the investigation, indicating that this species spawns all year round. We compared our results with other data recorded in the literature.