bluuebunny/crossref_metadata_2025 huggingface dataset:
Degradation of Alizarin Yellow R using UV/H2O2 advanced oxidation process
Authors: Narayanasamy Lavanyah , Murugesan Thanapalan
Published: October 2013

The homogeneous advanced oxidation process of ultraviolet (UV) radiation in presence of hydrogen peroxide (H2O2) was utilized to degrade Alizarin Yellow R, one of the most commonly used azo dyes in the textile industry. In this study, the effects of initial H2O2 concentration, initial dye concentration, initial pH, and temperature were examined to determine the optimum conditions for maximum degradation. Complete degradation was achieved within 1 h, for all the experimental conditions studied in the present work. The Box–Behnken response surface methodology (RSM) was used for optimizing the variables of the degradation process. Based on the estimated optimum conditions, 92.7% of degradation was achieved. The degradation process was found to follow first order kinetics. The estimated rate constants, along with the optimized conditions will be of useful for the design and scale up of the combined UV/H2O2 process for the said purpose. © 2013 American Institute of Chemical Engineers Environ Prog, 33: 482–489, 2014
Bank undercutting and tension failure by groundwater seepage: predicting failure mechanisms
Authors: Fox Garey A. , Felice Rachel G.
Published: October 2013

Groundwater seepage can lead to the erosion and failure of streambanks and hillslopes. Two groundwater instability mechanisms include (i) tension failure due to the seepage force exceeding the soil shear strength or (ii) undercutting by seepage erosion and eventual mass failure. Previous research on these mechanisms has been limited to non‐cohesive and low cohesion soils. This study utilized a constant‐head, seepage soil box packed with more cohesive (6% and 15% clay) sandy loam soils at prescribed bulk densities (1.30 to 1.70 Mg m−3) and with a bank angle of 90° to investigate the controls on failure mechanisms due to seepage forces. A dimensionless seepage mechanism (SM) number was derived and evaluated based on the ratio of resistive cohesion forces to the driving forces leading to instability including seepage gradients with an assumed steady‐state seepage angle. Tension failures and undercutting were both observed dependent primarily on the saturated hydraulic conductivity, effective cohesion, and seepage gradient. Also, shapes of seepage undercuts for these more cohesive soils were wider and less deep compared to undercuts in sand and loamy sand soils. Direct shear tests were used to quantify the geotechnical properties of the soils packed at the various bulk densities. The SM number reasonably predicted the seepage failure mechanism (tension failure versus undercutting) based on the geotechnical properties and assumed steady‐state seepage gradients of the physical‐scale laboratory experiments, with some uncertainty due to measurement of geotechnical parameters, assumed seepage gradient direction, and the expected width of the failure block. It is hypothesized that the SM number can be used to evaluate seepage failure mechanisms when a streambank or hillslope experiences steady‐state seepage forces. When prevalent, seepage gradient forces should be considered when analyzing bank stability, and therefore should be incorporated into commonly used stability models. Copyright © 2013 John Wiley & Sons, Ltd.
Network concepts to describe channel importance and change in multichannel systems: test results for the Jamuna River, Bangladesh
Authors: Marra Wouter A. , Kleinhans Maarten G. , Addink Elisabeth A.
Published: October 2013

Most of the largest rivers on Earth have multiple active channels connected at bifurcations and confluences. At present a method to describe a channel network pattern and changes in the network beyond the simplistic braiding index is unavailable. Our objectives are to test a network approach to understand the character, stability and evolution of a multi‐channel river pattern under natural discharge conditions. We developed a semi‐automatic method to derive a chain‐like directional network from images that represent the multi‐channel river and to connect individual network elements through time. The Jamuna River was taken as an example with a series of Landsat TM and ETM+ images taken at irregular intervals between 1999 and 2004.

We quantified the overall importance of individual channels in the entire network using a centrality property. Centrality showed that three reaches can be distinguished along the Jamuna with a different network character: the middle reach has dominantly one important channel, while upstream and downstream there are about two important channels. Temporally, relatively few channels changed dramatically in both low‐flow and high‐flow periods despite the increase of braiding index during a flood. Based on the centrality we calculated a weighted braiding index that represents the number of important channels in the network, which is about two in the Jamuna River and which is larger immediately after floods.

We conclude that the network measure centrality provides a novel characterization of river channel networks, highlighting properties and tendencies that have morphological significance. Copyright © 2013 John Wiley & Sons, Ltd.
Dynamic coefficient evaluation for an algebraic subgrid stress model
Authors: Bhushan S. , Walters D.K.
Published: October 2013

Static model coefficients for an algebraic subgrid stress (SGS) model are determined using a dynamic approach, based on results from simulations of isotropic decaying turbulence. The study was motivated by the discrepancies in energy transfer predictions using the previously documented coefficients (Bhushan and Warsi, Int. J. Numer. Meth. Fluids 2005; 49: 489–519). The discrepancies are identified to be due to inconsistent filter functions used in the analytic estimates and the simulations. The study emphasizes that SGS model development should use filter functions compatible with those inherent in CFD application solvers. The dynamic approach predicts consistent model and transfer coefficients for different grid resolutions and is judged to be a reliable basis for model coefficient adjustments. The predicted Leonard's stress coefficient and associated energy transfer coefficients agree very well with the analytic estimates using a Gaussian/cutoff combination filter. This suggests that the modeling of Leonard's stress term using a truncated Taylor series expansion is robust and may not benefit significantly from dynamic modeling. Validation simulations were performed for turbulent channel flow at Reτ = 180 and 590. The dynamic approach was found to be reliable only for the lower log‐layer of the Reτ = 590 case, where the scale invariance condition was satisfied. Nonetheless, in this narrow range, the model and transfer coefficients compare well with the isotropic case. The static coefficient algebraic model with new adjusted coefficients shows improved predictions compared with the previous coefficients, for both isotropic decaying turbulence and channel flow cases. Copyright © 2013 John Wiley & Sons, Ltd.
Emulator Rig for SOFC Hybrid Systems: Temperature and Power Control with a Real‐Time Software
Authors: Caratozzolo F. , Ferrari M. L. , Traverso A. , Massardo A. F.
Published: October 2013

This work is based on the hybrid system emulator plant developed by the Thermochemical Power Group (TPG) of the University of Genoa. This rig is composed of a 100 kW microturbine coupled with high temperature fuel cell emulation devices. A real‐time model is used for components not physically present in the laboratory (solid oxide fuel cell (SOFC), reformer, anodic circuit, off‐gas burner, cathode blower). It is necessary to evaluate thermodynamic and electrochemical performance related to SOFC systems. Using an User Datagram Protocol (UDP) based connection with the control/acquisition software, it generates a hardware‐in‐the‐loop (HIL) facility for hybrid system emulation. Temperature, pressure, and mass flow rate at the recuperator outlet and machine rotational speed are measured in the plant and used as inputs for the model. The turbine outlet temperature (TOT) calculated by the model is fed into the machine control system and the turbine electric load is changed to match the model TOT values (effective plant/model coupling to avoid modifications on microturbine controller). Different tests were carried out to analyze hybrid system technology through the interaction between an experimental plant and a real‐time model. Double step and double ramp tests of current and fuel provided the system dynamic response.
Design and execution of special foundation works for the deep excavations of the Thessaloniki Metro / Projektierung und Anwendung von Spezialtiefbaumethoden bei den tiefen Baugruben der Metro Thessaloniki
Authors: Vrettos Christos , Vassilakopoulou Georgia , Rizos Dimitris
Published: October 2013

The new metro line in Thessaloniki includes, besides the excavation of two twin tunnels, the construction of 13 stations with central platform in settlement‐reducing top‐to‐down construction method. Due to restrictions in available space, it was necessary to dispense with the construction of an inner shell. Further constraints were the soft and highly inhomogeneous soil, the large excavation depths in groundwater, and the earthquake‐resistant design of the structures. The special foundation works executed for permanent uplift safety as well for the soil strengthening in front of the excavation walls are described for representative stations.

Die neue U‐Bahn in Thessaloniki umfasst, neben dem Schildvortrieb zweier Röhren, die Errichtung von 13 Bahnhöfen mit zentralem Bahnsteig in verformungsarmer Deckelbauweise. Wegen der engen Platzverhältnisse musste dabei auf eine Innenschale verzichtet werden. Weitere erschwerende Randbedingungen sind der weiche, stark inhomogene Untergrund, die große Aushubtiefe im Grundwasser und die erdbebengerechte Auslegung der Tragkonstruktion. Für typische Bahnhöfe werden die Spezialtiefbaumaßnahmen zur dauerhaften Auftriebssicherung sowie zur Verstärkung des Fußwiderlagers der tiefen Baugruben vorgestellt.
The 1998 eruption of Axial Seamount: New insights on submarine lava flow emplacement from high‐resolution mapping
Authors: Chadwick W. W. , Clague D. A. , Embley R. W. , Perfit M. R. , Butterfield D. A. , Caress D. W. , Paduan J. B. , Martin J. F. , Sasnett P. , Merle S. G. , Bobbitt A. M.
Published: October 2013

Axial Seamount, an active submarine volcano on the Juan de Fuca Ridge at 46°N, 130°W, erupted in January 1998 along 11 km of its upper south rift zone. We use ship‐based multibeam sonar, high‐resolution (1 m) bathymetry, sidescan sonar imagery, and submersible dive observations to map four separate 1998 lava flows that were fed from 11 eruptive fissures. These new mapping results give an eruption volume of 31 × 106 m3, 70% of which was in the northern‐most flow, 23% in the southern‐most flow, and 7% in two smaller flows in between. We introduce the concept of map‐scale submarine lava flow morphology (observed at a scale of hundreds of meters, as revealed by the high‐resolution bathymetry), and an interpretive model in which two map‐scale morphologies are produced by high effusion‐rate eruptions: “inflated lobate flows” are formed near eruptive vents, and where they drain downslope more than 0.5–1.0 km, they transition to “inflated pillow flows.” These two morphologies are observed on the 1998 lava flows at Axial. A third map‐scale flow morphology that was not produced during this eruption, “pillow mounds,” is formed by low effusion‐rate eruptions in which pillow lava piles up directly over the eruptive vents. Axial Seamount erupted again in April 2011 and there are remarkable similarities between the 1998 and 2011 eruptions, particularly the locations of eruptive vents and lava flow morphologies. Because the 2011 eruption reused most of the same eruptive fissures, 58% of the area of the 1998 lava flows is now covered by 2011 lava.
Large flow shears around auroral beads at substorm onset
Authors: Hosokawa K. , Milan S. E. , Lester M. , Kadokura A. , Sato N. , Bjornsson G.
Published: October 2013

We present a fine‐scale electrodynamic structure behind the auroral beads observed immediately before substorm onset, as inferred from high spatial and temporal resolution measurements of substorm with an all‐sky TV camera (ATV) and a coherent high frequency radar of Super Dual Auroral Radar Network in Iceland. On the night of 24 September 2006, the ATV observed eastward propagating auroral beads in the initial brightening arc of a substorm just prior to the poleward expansion. During the sequential passage of the beads across the radar beams, the radar detected large velocity flow shears whose magnitude was in excess of 0.27 s−1. The observations suggest that flow shears were located very close to the center of the beads; thus, they corresponded to electric fields converging toward the beads, which is consistent with the existence of upward field‐aligned currents (FACs) flowing out of the beads. The temporal and spatial resolutions of the current radar measurement were still insufficient for fully resolving the detailed electrodynamic structure behind the fast moving auroral beads. At least, however, we can suggest the existence of highly localized filamentary FAC structures behind the beads, which would be an important consequence of possible plasma instabilities operating in the M‐I coupling region or near the equatorial plane of the magnetosphere.
High ozone concentrations on hot days: The role of electric power demand and NOx emissions
Authors: He Hao , Hembeck Linda , Hosley Kyle M. , Canty Timothy P. , Salawitch Ross J. , Dickerson Russell R.
Published: October 2013

High ambient temperatures intensify photochemical production of tropospheric ozone, leading to concerns that global warming may exacerbate smog episodes. This widely observed phenomenon has been termed the climate penalty factor (CPF). A variety of meteorological and photochemical processes have been suggested to explain why surface ozone increases on hot days. Here, we quantify an anthropogenic factor previously overlooked: the rise of ozone precursor emissions on hot summer days due to high electricity demand. Between 1997 and 2011, power plant emissions of NOx in the eastern U.S. increased by ~2.5–4.0%/°C, raising surface NOx concentrations by 0.10–0.25 ppb/°C. Given an ozone production efficiency (OPE) of ~8 mol/mol based on the 2011 NASA DISCOVER‐AQ campaign, at least one third of the CPF observed in the eastern U.S. can be attributed to the temperature dependence of NOx emissions. This finding suggests that controlling emissions associated with electricity generation on hot summer days can mitigate the CPF.
Application of a new data operator‐splitting data assimilation technique to the 3‐D VERB diffusion code and CRRES measurements
Authors: Shprits Yuri , Kellerman Adam , Kondrashov Dmitri , Subbotin Dmitriy
Published: October 2013

In this study we present 3‐D data assimilation using CRRES data and 3‐D Versatile Electron Radiation Belt Model (VERB) using a newly developed operator‐splitting method. Simulations with synthetic data show that the operator‐splitting Kalman filtering technique proposed in this study can successfully reconstruct the underlying dynamic evolution of the radiation belts. The method is further verified by the comparison with the conventional Kalman filter. We applied the new approach to 3‐D data assimilation of real data to globally reconstruct the dynamics of the radiation belts using pitch angle, energy, and L shell dependent CRRES observations. An L shell time cross section of the global data assimilation results for nearly equatorially mirroring particles and high and low values of the first adiabatic invariants clearly show the difference between the radial profiles of phase space density. At μ = 700 MeV/G cross section of the global reanalysis shows a clear peak in the phase space density, while at lower energy of 70 MeV/G the profiles are monotonic. Since the radial profiles are obtained from one global reanalysis, the differences in the profiles reflect the differences in the underlying physical processes responsible for the dynamic evolution of the radiation belt energetic and relativistic electrons.
SnCl4‐Induced Unsymmetrical Cleavage of Bis(N,N‐diethylcarbamoyltelluro)‐arylmethanes: Generation of Tellurobenzaldehydes
Authors: Shimada Kazuaki , Higashi Takumi , Gong Yaling , Aoyagi Shigenobu , Takikawa Yuji , Ogawa Satoshi
Published: October 2013

Tellurobenzaldehydes bearing an electron‐withdrawing substituent were generated by way of SnCl4‐induced unsymmetrical cleavage of bis(N,N‐dialkylcarbamoyltelluro)arylmethanes, and were trapped using 2,3‐dimethyl‐1,3‐butadiene.
Two New Naphthoquinone Derivatives from Lysionotus pauciflorus
Authors: Zhong Yu‐Jiao , Wen Qing‐Fa , Li Cong‐Ying , Su Xue‐Hui , Yuan Zhi‐Peng , Li Yan‐Fang
Published: October 2013

Two new naphthoquinones, (2R)‐6,8‐dihydroxy‐α‐dunnione (1), 6,8‐dihydroxy‐2,7‐dimethoxy‐3‐(1,1‐dimethylprop‐2‐enyl)‐1,4‐naphthoquinone (2), together with three known compounds, (2R)‐6,8‐dihydroxy‐7‐methoxy‐α‐dunnione (3), nevadensin (4), and lysioside C (5), were isolated from the whole plant of Lysionotus pauciflorus. Their structures were established by spectroscopic methods. Hydroxylated naphthoquinones are reported to occur in a Lysionotus species for the first time. The cytotoxic activities of compounds 1–3 were evaluated in vitro against a panel of tumor cell lines.
Influence of Guanidinium Salts and Other Ionic Liquids on the Three‐Component Aza‐DielsAlder Reaction
Authors: Mert‐Balci Fadime , Imrich Hans‐Georg , Conrad Jürgen , Beifuss Uwe
Published: October 2013

The three‐component reaction of aniline, benzaldehyde, and dienophiles such as 2,3‐dihydrofuran, ethyl vinyl ether, 2,3‐dihydropyran, and cyclopentadiene can be promoted by ionic liquids like imidazolium salts and guanidinium salts under thermal as well as microwave conditions. The chemical yield as well as the diastereoselectivity of the Povarov reaction strongly depend on the ionic liquid employed. The guanidinium salts can be recycled and reused several times without loss of reactivity.
Therapy‐induced enrichment of putative lung cancer stem‐like cells
Authors: Freitas Daniela P. , Teixeira Cristina A. , Santos‐Silva Filipe , Vasconcelos M. Helena , Almeida Gabriela M.
Published: October 2013

Tumour drug resistance is a major issue in the management of lung cancer patients as almost all lung tumours are either intrinsically resistant or quickly develop acquired resistance to chemotherapeutic drugs. Cancer drug resistance has recently been linked, at least in part, to the existence of cancer stem‐like cells (CSLCs), a small sub‐population of cells within the tumour that possess stem‐like properties. CSLCs are often isolated by fluorescence activated cell sorting (FACS) according to the expression of certain stem‐like cell membrane markers. Conflicting results regarding the specificity of particular stem cell surface markers for isolating CSLCs have, however, been recently reported. Therefore, alternative strategies enabling the identification and study of CSLCs should be considered, particularly in tumour types where appropriate stem cell markers are not well established and validated, like in lung cancer. In this article, we review data indicating therapy‐selection as a valid approach for putative lung CSLCs enrichment. We believe that this strategy would be determinant for correctly assessing and characterising the sub‐populations of CSLCs that are able to survive chemo or radiotherapy regimens and, at the same time, also have the ability to recapitulate and sustain tumour growth. Using therapy‐induced enrichment of CSLCs may, therefore, prove to be an extremely useful method for studying CSLCs and provide new clues regarding potential therapeutic targets for their efficient elimination, which will undoubtedly play a decisive role in improving lung cancer patients' survival.
Messenger RNA vaccine based on recombinant MS2 virus‐like particles against prostate cancer
Authors: Li Jinming , Sun Yanli , Jia Tingting , Zhang Rui , Zhang Kuo , Wang Lunan
Published: October 2013

Prostate cancer (PCa) is the most diagnosed cancer in the western male population with high mortality. Recently, alternative approaches based on immunotherapy including mRNA vaccines for PCa have shown therapeutic promise. However, for mRNA vaccine, several disadvantages such as the instability of mRNA, the high cost of gold particles, the limited production scale for mRNA‐transfected dendritic cells in vitro, limit their development. Herein, recombinant bacteriophage MS2 virus‐like particles (VLPs), which based on the interaction of a 19‐nucleotide RNA aptamer and the coat protein of bacteriophage MS2, successfully addressed these questions, in which target mRNA was packaged by MS2 capsid. MS2 VLP‐based mRNA vaccines were easily prepared by recombinant protein technology, nontoxic and RNase‐resistant. We show the packaged mRNA was translated into protein as early as 12 hr after phagocytosed by macrophages. Moreover, MS2 VLP‐based mRNA vaccines induced strong humoral and cellular immune responses, especially antigen‐specific cytotoxic T‐lymphocyte (CTL) and balanced Th1/Th2 responses without upregulation of CD4+ regulatory T cells, and protected C57BL/6 mice against PCa completely. As a therapeutic vaccine, MS2 VLP‐based mRNA vaccines delayed tumor growth. Our results provide proof of concept on the efficacy and safety of MS2 VLP‐based mRNA vaccine, which provides a new delivery approach for mRNA vaccine and implies important clinical value for the prevention and therapy of PCa.
Advances in cancer epidemiology in Japan
Authors: Tanaka Hideo
Published: October 2013

Epidemiologists in Japan have been performing calculations to estimate nationwide cancer incidence rates as well as 5‐year survival rates using population‐based cancer registry data. There have been remarkable changes in cancer incidence and/or mortality in cancers of the lung, liver and stomach, which were thought to be attributed to the changing impact of exposure to cigarette smoking, chronic hepatitis C virus infection and Helicobacter pylori infection, respectively. In systematic reviews providing evidence in risk/protective factors for cancer sites using case–control and cohort studies of the Japanese population, there were associations between cancer sites (esophagus, stomach, colo‐rectum, liver, pancreas, lung and breast) and various lifestyle factors. In the past 10 years, a hospital‐based case–control study at Aichi Cancer Center provided valuable evidence of gene‐environment interaction on the development of cancer [i.e., the effects of aldehyde dehydrogenase‐2 (ALDH2) polymorphism and heavy alcohol drinking on esophageal cancer, ALDH2 polymorphism and smoking on lung cancer, methylenetetrahydrofolate reductase polymorphism and heavy alcohol drinking on pancreatic cancer]. The database with stored DNA was also used and identified seven loci containing significant but low‐penetrance polymorphisms associated with the development of breast cancer. These findings together with established risk factors are likely to be useful to predict personalized breast cancer risk in East Asian women. In 2005, the Japan Multi‐Institution Collaborative Cohort (J‐MICC) study was launched to elucidate gene‐environment interactions as well as to confirm preclinical diagnostic biomarkers of cancer. J‐MICC, which has recruited 92,000 healthy individuals by the end of 2012, will follow the individuals until 2025.
Now you see it, now you don't – a case of “Vanishing Bone”
Authors: Piggott Bruce
Published: October 2013

Vanishing bones – no, not the movie fantasy of the “Invisible Man” but a case of a rare disease which causes massive osteolysis or progressive bone dissolution. The idiopathic disease, which causes bone to be replaced by angiomatous tissue, has resulted in the disappearance of this patient's right clavicle and glenoid. Diagnostic evaluation can sometimes prove difficult but ironically in this age of higher technology, plain radiography has demonstrated to be more effective for a definitive diagnosis than Nuclear Medicine, MRI, CT, etc. The rate of progress of the disease is as unpredictable as the prognosis. While a variety of treatments have been tried, the results have been inconsistent and as yet there is still no consensus on successful patient treatment.
Computed Tomography Colonography: Patient Tolerance to CO2 Insufflation
Authors: Gaspar Monique D.
Published: October 2013

Computed Tomography (CT) colonography, also known as “virtual colonoscopy” is a relatively new technique for colorectal evaluation. It allows imaging of the colonic mucosa and wall similar to those obtained during conventional colonoscopy. The aim of the present study was to investigate patient tolerance to carbon dioxide (CO2) insufflation during CT colonography and whether the CO2 insufflation was adequate to distend the bowel sufficiently for radiological diagnosis. This study also aimed to demonstrate a relationship between patient age and patient tolerance to CO2 insufflation. This research investigated 22 patients (50 per cent male, mean age 64 years) with a variety of clinical indications. CO2 was insufflated through a rectal catheter to the maximum extent of patient tolerance. Volumetric data of the abdomen and pelvis was acquired in a single breathold using a GE Lightspeed Plus multislice CT scanner with the patient in the supine and prone positions. The CO2 insufflation time for the supine and prone series was recorded and the patients rated their tolerance to the CO2 insufflation based on a modified Likert scale. The results were analysed using scatter graphs and Pearson's Correlation Coefficient, mapping the CO2 insufflation time for the prone and supine series and comparing it to patient age. The findings indicate that there was a statistical significance between patient age and patient tolerance (r=−0.47), however, no statistical significance was found between the other variables. This may be due to several reasons including variable bowel length and a small sample. Additional studies are required with a larger sample in order to further investigate this topic.
Mandatory Continuing Professional Education: Do we need it?
Authors: Field Nikki
Published: October 2013

In view of the recommendations made in the “Report of the Radiation Oncology Inquiry — A Vision for Radiotherapy” that radiation therapists should prove their competence through continuing professional education (CPE) and the decision by the Council of the Australian Institute of Radiography to mandate continuing professional development for members from January 2005, it seems timely to address the CPE voluntary versus mandatory debate for medical radiation scientists. This paper explores the nature of CPE and presents an argument for CPE to remain voluntary. The two main reasons for this stance are the lack of evidence that CPE improves professional practice and the violation of adult learning principles inherent in mandatory education. Due to the paucity of information about this issue in medical radiation science professions arguments are drawn from across the health sciences professions. Needs assessment and evaluation of CPE programs will also be examined.
MR imaging of Crohn's disease: The experience at the Royal Melbourne Hospital
Authors: Perry Chris
Published: October 2013

Until recently, magnetic resonance imaging (MRI) has had little to offer the physician or surgeon in the area of small bowel gastro‐intestinal (GI) imaging. Long scan times leading to motion artifacts and poor image quality as well as a lack of good quality imaging coils have all contributed to this fact. However, in the last 5–10 years, these problems have been overcome by the creation of very fast sequences enabling breath‐hold scan times, as well as increases in surface coil technology (phased‐array abdominal coils) to increase signal‐to‐noise ratio and image quality. In the light of these new advances, MRI is being used increasingly to aid in the diagnosis of certain GI tract diseases. This paper looks at the ability of MRI to diagnose the chronic inflammatory bowel condition known as Crohn's disease, with a discussion on the experience of our department to date.
Computed tomography imaging for superior semicircular canal dehiscence syndrome
Authors: Dobeli Karen
Published: October 2013

Superior semicircular canal dehiscence is a newly described syndrome of sound and / or pressure induced vertigo. Computed tomography (CT) imaging plays an important role in confirmation of a defect in the bone overlying the canal. A high resolution CT technique utilising 0.5 mm or thinner slices and multi‐planar reconstructions parallel to the superior semicircular canal is required. Placement of a histogram over a suspected defect can assist CT diagnosis.
Student initiated clinical activities: a review of a new assessment technique for clinical education
Authors: Reed Warren
Published: October 2013

Introduction This article presents a review of a new clinical assessment technique designed to encourage student learning by utilising choice, negotiation and reflection as part of the assessment process. The students' perceptions of this assessment were requested as part of a quality review.

Methods A questionnaire was distributed to all first year students (101) and subsequently the same questionnaire was distributed to the same students in the third year (92) to gain a longitudinal perspective. The questionnaire included 10 closed item statements related to a five point Likert scale and one open ended question. Descriptive analysis was carried out on the closed ended statements and thematic analysis on the open‐ended statement.

Result The students surveyed agreed with the majority of statements. They agreed that the assessment had given them a deeper understanding of the activities they chose to perform.

Conclusion This review has provided important feedback to improve this new assessment technique in the future.
Giant cerebral aneurysm: 3D computed tomography angiography vs. rotational 3D digital subtraction angiography
Authors: Perry Chris D.
Published: October 2013

The purpose of writing this case study was to compare the accuracy of computed tomography angiography (CTA) and 3D rotational digital subtraction angiography (3D DSA) in demonstrating a giant cerebral aneurysm and its relationship to the parent artery. The patient was a 36‐year‐old female who presented to our department with a suspected cerebral aneurysm as seen on a non‐contrast computerised tomography (CT) brain scan. The CTA and 3D DSA were performed on consecutive days and both demonstrated a giant aneurysm arising from the right posterior cerebral artery. A series of 3D images were produced from both modalities, with each possessing sub‐millimeter spatial resolution. After comparison between the two 3D data sets, it was evident that the 3D DSA was superior in delineating the relationship between the aneurysm and its parent artery. The CTA suffered from partial voluming in this area and it seemed as though a connection was present between the aneurysm and posterior cerebral artery distal to the aneurysm neck. Based on the CTA alone, an incorrect report would have resulted. Surgery later confirmed the absence of this connection and, thereby, proved that 3D DSA was more accurate in the visualisation of this patient's aneurysm. Treatment for this patient could therefore be planned more confidently based on the 3D DSA findings.
Technical knowledge and skills in undergraduate radiation therapy: The University of Newcastle experience
Authors: Hopkins Melissa G. , Callan Scott A. , Cant Jennifer G. , Dempsey Shane
Published: October 2013

Radiation therapy (RT) technologies and the technical skills required have undergone an extended period of change and advancement. The University of Newcastle's RT curriculum has met this challenge by developing a technologically layered curriculum that not only retains the basic fundamental concepts underpinning RT, but also reflects current and emerging technology, as well as the associated skill developments.

This paper outlines how past, current and future RT technical approaches and technical skills are integrated into the current undergraduate RT curriculum.
The use of gonadal shielding in singular common diagnostic radiographic procedures
Authors: Bowen Sean A. , Clarke Ryan , Dickson Samuel S. , McLennan Christopher M. , Stonehouse Mark K. , Wilcher Tobey F. , Buxton Anthony J.
Published: October 2013

The aim of this study was to make recommendations regarding when the use of gonadal shielding is significant in reducing gonad dose for common diagnostic procedures. Two separate literature reviews were conducted and the data compared. The first review proposed to determine average entrance surface doses (ESD) for common diagnostic procedures and the second to determine a threshold for exposure to the gonads below which risk of genetic effects was negligible. By comparing accepted ESD and associated gonad doses with the threshold dose, recommendations for each procedure could be made. This recommendation would be that either gonadal shielding is significant in reducing risk of genetic effects for this examination, or that gonadal shielding would make no difference because the doses involved are negligible. Common procedures were selected as well as common series, based on the fact that these procedures contribute relatively high dose to the gonads. A threshold dose to the gonads was established to be 10 mGy. Below this level of exposure, genetic risk to the gonads is considered negligible. It was found that none of the series or individual exams contributed significant dose to the gonads (dose levels above the 10 mGy threshold). It should be noted, however, that this recommendation applies only to individual patients receiving individual exposures. The effect of repeat examinations or the risk to a population of patients was not considered. It was also found that gonadal shielding may alleviate fears of radiation exposure in patients. It was recommended that for all individual examinations/series included in this study that gonadal shielding was unnecessary because the doses involved present negligible genetic risk to the patient. However, best practice in radiography includes upholding the ‘As low as reasonably achievable’ principle (ALARA) and considering the fears of patients, and it is for this reason that gonadal shielding should be used.
Radiographer reporting of trauma images: United Kingdom experience and the implications for evolving international practice
Authors: Hardy Maryann , Snaith Beverly , Smith Tony
Published: October 2013

Some United Kingdom (UK) radiographers share the task of radiological reporting with radiologists. This paper aims to describe the current status of radiographer reporting of trauma images in the countries of the UK and reflect on its relevance to the development of similar advanced practice roles internationally.

In February 2007, a cross‐sectional survey with respect to radiographer reporting was conducted of 456 UK hospitals with an Emergency Department (ED) or Minor Injuries Unit (MIU). The main outcome measures were the number of reporting radiographers; number of half‐day radiographer reporting sessions per week; availability of, and radiographer involvement in ‘hot’ reporting. A total of 306 (67.1%) responses were received. Reporting radiographers were employed at 56.9% (174/306) of the respondent hospitals. Of hospitals with an ED, 70% (142/203) employed reporting radiographers compared to 31.1% (32/103) of those with a MIU. At 146 of the 174 hospitals that employed reporting radiographers (83.9%) there were between one and six radiographers involved. At 155 hospitals (155/174; 89.1%) radiographers performed between 0 and 10 reporting sessions each week. Most reported for one or two sessions. ‘Hot’ reporting operated at only 11.1% (34/306) of the respondent hospitals, with radiographers leading this service at 64.7% (22/34) of those sites.

The rate of radiographer reporting uptake in UK hospitals appears to have slowed. Also, few radiographers are engaged in ‘hot’ reporting of trauma images. The prevalent UK model of ‘cold’ radiographer reporting may not be transferable to other countries where there is a need is for immediate and accurate reporting of trauma images.
Characteristics of good practice — how to be a good radiographer
Authors: Egestad Helen
Published: October 2013

The study's objective was to define the characteristics of ‘good practice’ in radiography.

Method Observations of six radiographers performing CT examinations on patients, and in‐depth interviews with four radiographers. Interviews and observations are analysed using Kvale's phenomenological method.

Results Radiographers perform examinations differently. Differences are especially apparent in regard to how they relate to their patients. The radiographers viewed their job in three different ways: those who saw radiography as a technical job; those ambivalent as to whether the job is of a technical or a relational nature; and those who sought to utilise technique via the patient. Good radiography is characterised by the combination and integration of technical and patient‐oriented actions.

Discussion The results of this study challenge the profession's view of its own practice and the overall value criteria to employ when evaluating radiographic practice.
Does Australian state location influence MRS practitioners' access to and use of the internet?
Authors: Shanahan Madeleine
Published: October 2013

The internet is an important information resource used by health practitioners to access the most current health and medical information. In Australia, the public health system is managed and operated independently at state and territory level and this raises the potential for differential access to the internet to exist within workplaces across government boundaries such as Australian states. This paper examines the effect of Australian state on access to and use of the internet by comparing medical radiation science (MRS) workplaces in Queensland and Victoria.

Survey design was used to collect data. In 2007, a questionnaire was sent to 1067 Australian MRS practitioners in Victoria and Queensland, with a response rate of 31.1%. The results show that internet access within workplaces varied across and within Australian states. Victorian practitioners in the public sector reported the highest level of internet connectivity within their workplace with 64% of practitioners reporting internet access on all workplace computers compared to 13% of practitioners employed in the public sector in Queensland (P = 0.000). Victorian practitioners in the public sector also reported greater use of the internet (P = 0.000) and valued it higher as a resource for updating their professional knowledge (P = 0.011) than their colleagues in the public sector in Queensland. Approximately one‐third of practitioners employed in the private sector in both Queensland and Victoria reported internet access on all computers in their workplace (P = 0.885). There exists a digital divide within MRS workplaces which must be addressed so regardless of state or health sector of employment, practitioners can avail themselves of current health and medical information made available through the internet that supports them in staying up‐to‐date with the changing knowledge base of their profession.
Delayed treatment for a case of acute ischaemic stroke using mechanical embolectomy — the L5 Merci Retriever
Authors: Velkovic J , McEwan S , Coulthard A
Published: October 2013

Endovascular therapies for acute ischaemic stroke represent important alternatives or adjuncts to thrombolysis. A middle‐aged male suffered a Thrombolysis in Myocardial Infarction (TIMI) Grade 0 distal left middle cerebral artery (LMCA) occlusion resulting in right hemiparesis and dysphasia. Intravenous thrombolysis was contraindicated due to pre‐existing anticoagulant therapy and associated risk of intracranial haemorrhage. The patient underwent rescue mechanical embolectomy with an L5 Merci Retriever, with adjuvant local intra‐arterial (IA) thrombolysis. Successful TIMI Grade 3 restoration of LMCA blood flow occurred within eight hours of ictus. Aphasia resolved within 24 hours, whilst other motor and speech symptoms gradually improved over 6 months, allowing the patient to resume work and independent living. Mechanical embolectomy appears to be a safe and effective alternative in cases of delayed presentation, or where intravenous thrombolysis is contraindicated. Combined mechanical embolectomy and adjuvant IA thrombolysis, instituted within eight hours of ictus in an anticoagulated patient, achieved favourable clinical outcome (modified Rankin Score of 2) without major thromboembolic or haemorrhagic complications.
The feasibility of using radiogrammetry in comparing cortical bone thickness in human and non‐human tibiae
Authors: Croker SL , Reed W , Donlon D
Published: October 2013

A method was sought by which to measure the cortical thickness of long bones, as a prelude to a large comparative study of cortical bone thickness. Radiography presents a simple, non‐destructive method for visualising internal features of bones. Radiogrammetry, though frequently used for cortical bone measurements, has predominantly focused on the metacarpals in the literature, while studies examining the method for large long bones are less plentiful. The tibia was used in this study, with samples from humans, kangaroos, sheep, dogs, pigs and cattle. Digital radiographs were obtained from the anterior and medial sides of the bone; images were then displayed on screen, magnified and measured. Bone diameter, medulla diameter and cortical thickness were measured for each projection, at the midpoint of the tibia. Some difficulty was encountered due to the lack of clarity of the endosteal border of the cortex, though intra‐observer tests found the method to be largely reproducible. Magnification and distortion of the image were observed, particularly on larger bones as they were situated a greater distance above the film surface. These factors were not considered too limiting; furthermore, the simplicity of the method means it would be generally suitable for the proposed study.
Using online peer feedback in formative assessment for medical sonography students teaching: the student view
Authors: Thoirs KA
Published: October 2013

Purpose: This paper reports the results of a survey of external medical sonography university students which investigated their perceptions of anonymous online peer feedback formative assessments. Peer feedback is gaining popularity among academic teachers to both promote deeper learning and reduce heavy marking loads. Methods: In a cross sectional study design, 77 postgraduate students enrolled in an externally delivered sonography course in 2009 were invited to participate in a student evaluation survey. Results: Sixteen students (21%) responded to the survey. Students registered positive perceptions on a Likert scale for items asking about the value of the learning experiences, their level of comfort in participating in peer feedback, and their acceptance of using a web based medium. Anonymity rated highly as an important element of the assessments. Two‐tailed Mann‐Whitney U tests demonstrated no significant differences (P < 0.05) between student perceptions of assessment items with and without peer feedback, or between the feedback provided by their peers and the feedback provided by the teacher. Conclusion: Open questions provided insight in how the students perceived the assessment could be improved. Future derivations of the described assessment process should use a more user‐friendly online platform, and the breadth of course content should be expanded so that all learning objectives and content are integrated into formative assessment. As well as being more acceptable to students this approach is more likely to motivate students to meet learning objectives, and encourage active learning. Further evaluation will be required as the assessments are modified.
Developing a qualitative framework for analysis of student journals
Authors: Findlay N , Dempsey S , Warren‐Forward H
Published: October 2013

Learning from work is an important aspect of student and professional life when working within the health profession. Personal journals are one way that health professionals are able to document their experiences. These journals also hold a wealth of information about the student experience on placement. To analyse the content of journals a qualitative research analytical method is required.

There are many different methodological underpinnings or approaches within qualitative research and it is important that the researchers consider their own world view and the context of the research and the data to be evaluated when selecting a qualitative methodology to utilise.

This paper discusses an overview of the process of choosing a qualitative framework for the analysis of the descriptions contained within student personal journals. The paper describes the development and validity checking of a coding or sourcebook for qualitative descriptive analysis of student personal journals.
CT dose reduction is achievable: one site's experience with a dose optimisation process
Authors: Smith K , Mandarano G
Published: October 2013

An Emotion 6 Siemens Multi‐Detector CT scanner (Erlangen, Germany) was installed at the review site in December 2005. Improving upon the manufacturer's default exposure settings, the authors sought to perform a quality review to reduce ionising radiation dose delivered to patients. Dose associated with CT examinations across the major body regions was assessed. Dose savings ranged from 11% to 70% when compared to the manufacturer's default settings. Dose comparisons are also made with the European Standards and the United Kingdom Field Survey.
A patient presenting with an advanced squamous cell carcinomas to the left thigh
Authors: Coles AJ
Published: October 2013

Introduction: In Australia, Squamous Cell Carcinomas (SCC) are the second most common form of skin cancer and is most frequently present in the population aged 50 years and older. SCCs characteristically are slow growing tumours, but are known to enlarge rapidly in some cases. Apart from presenting with a lesion, patients are usually asymptomatic. Radiation therapy is the treatment option when surgery is not feasible; the patient has metastatic disease or high risk cutaneous SCC. Systemic chemotherapy is only used when metastatic disease is present. Case presentation: A male patient in his late forties presented to clinic with a 25 cm fungating SCC lesion to the left upper thigh. Radiation therapy treatment via non coplanar beams was prescribed to treat the lesion to 66 Gy in 33 fractions. Chemotherapy was not an option due to the patient's co‐morbidities. This case report follows the patient from the start to 84 weeks post treatment. Conclusion: The patient discussed in this case report found the treatment process and overall outcomes were satisfactory despite the advanced presentation of the disease and anxieties about hospitals and medical staff. The radiation therapists involved in this patient's treatment process found the case challenging, and it gave them the opportunity to utilise their skills and knowledge to approach the case with a range of alternative techniques. In this case, treatment achieved the desired outcome for the patient.