bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimization of the motion trajectory for standing from a seated position by considering muscular load based on electromyography
Authors: Kushida Daisuke , Asakura Yuki , Kitamura Akira
Published: August 2012

Standing from a chair is an important task of daily living for physically handicapped people. In a rehabilitation center, a healthcare professional plans motion on the basis of experience and knowledge so that a patient may stand up with little load. Therefore, there is a problem that the plan is occasionally different with each healthcare professional. In this paper, a method for generation of a motion trajectory to stand from a seated position with little load by using a genetic algorithm (GA) is proposed. The human body is expressed as a three‐rigid‐link model. In the model, the ankle, the knee, and the waist are set as the joints. Electromyographic (EMG) measurements of the muscle driving each joint were made and a model relating each joint torque to the EMG was constructed using the ARX model. The motion trajectory to stand from a seated position was generated by using a GA with its evaluation function based on the constructed ARX model. The generated motion trajectory was evaluated by experimental work with eight healthy subjects. The effect of the proposed method was objectively verified by the subjects' EMGs. In addition, the subjective effect of the proposed method was verified by analysis of the variance of the subjects' impressions. © 2012 Wiley Periodicals, Inc. Electron Comm Jpn, 95(9): 36–43, 2012; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/ecj.11395
A Policy Description and Its Execution Scheduling for Automated IT Systems Management
Authors: Kudo Yutaka , Morimura Tomohiro , Masuoka Yoshimasa , Komoda Norihisa
Published: August 2012

In order to execute multiple policies in a policy‐based automation system safely and efficiently, we propose and develop a concurrency control mechanism for policy‐based automation systems. This mechanism analyzes the logical structure of the target application system to identify the IT resources affected by the policy action, and locks the resources to prevent conflicts between multiple policies. An efficient preemptive scheduling scheme for multiple policy executions is also developed. © 2012 Wiley Periodicals, Inc. Electron Comm Jpn, 95(9): 27–35, 2012; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/ecj.11399
Three‐way translocation (X;20;16)(p11;q13;q23) in essential thrombocythemia implicates NFATC2 in dysregulation of CSF2 expression and megakaryocyte proliferation
Authors: Vieira Luís , Vaz Andreia , Matos Paulo , Ambrósio Ana Paula , Nogueira Manuel , Marques Bárbara , Pereira Ana Marques , Jordan Peter , da Silva Maria Gomes
Published: August 2012

Essential thrombocythemia (ET) is a myeloproliferative neoplasm essentially characterized by excessive production of platelets. Molecular pathogenesis of ET is linked in approximately half of the patients to intracellular cytokine signaling dysregulation as a result of thrombopoietin receptor or Janus kinase 2 (JAK2) mutations. However, genetic defects underlying cytokine transcription have not been associated with ET. Using molecular cytogenetics and whole‐genome array analyses, we uncovered a submicroscopic deletion at 20q13.2 in a JAK2V617F‐positive ET patient with an acquired complex chromosome translocation. The deletion encompassed the nuclear factor of activated T‐cells, cytoplasmic, calcineurin‐dependent 2 (NFATC2) gene that encodes a transcription factor involved in the regulation of hematopoietic cytokines. RNA interference‐mediated suppression of NFATC2 mRNA or pharmacological inhibition of NFATC2 protein with 11R‐VIVIT in cultured JAK2V617F‐positive SET‐2 megakaryocytes increased colony stimulating factor 2 (granulocyte‐macrophage) (CSF2) mRNA and promoted cell proliferation. Moreover, impairment of NFATC2–calcineurin interaction with 11R‐VIVIT further reduced the transcription of the NFATC2 gene. Antibody‐mediated neutralization of CSF2 cytokine in inhibitor‐treated cells prevented 11R‐VIVIT‐induced cell proliferation, indicating that impairment of NFATC2–calcineurin interaction promotes megakaryocyte proliferation through up‐regulation of CSF2 transcription. Our results suggest a model in which haplo‐insufficiency of NFATC2 cooperates with activation of the JAK–STAT signaling pathway in the pathogenesis of JAK2V617F‐positive ET with del(20q). These results further indicate that pathogenesis of ET may be linked to genetic defects of other transcription factor genes involved in the regulation of cytokine expression. © 2012 Wiley Periodicals, Inc.
Late Tournaisian Waulsortian‐like carbonate mud banks from South China (Longdianshan Hill, central Guangxi): preliminary investigations
Authors: Aretz Markus , Poty Edouard , Devuyst François‐Xavier , Hance Luc , Hou Hongfei
Published: August 2012

For the first time Waulsortian‐like carbonate mud banks are described from lower Mississippian strata of South China. The carbonate mud banks occur in the upper member of the Long'an Formation (late Tournaisian in age) at Longdianshan Hill (near Liuzhou, central Guangxi). They are domal to tabular in shape, and locally form aggregates. Horizontal and vertical differentiation of the banks into core and flank facies was not observed. Onlapping thin‐bedded, grainy off‐bank facies indicates that the banks had depositional relief. The carbonate mud banks are composed of a mixture of two basic microfacies types: (1) spiculitic wackestone with diverse fauna and (2) fine‐grained bioclastic wackestone and packstone. Colour changes indicate the presence of several mud generations, but syndepositional cavities are limited in volume. More common are larger spar‐filled cavities representing matrix dissolution. The common reddish colour of the bank facies might be related to hematite‐rich microaerophilic iron bacteria. Formation of the carbonate mud banks took place in an outer platform setting in several tens of metres water depth under dysphotic conditions during the relative sea‐level rise of a third‐order sequence. The carbonate mud banks at Longdianshan Hill share some characteristics of classical Waulsortian banks in Europe, notably the presence of bryozoans, crinoids and sponges, different mud generations and spar‐filled cavities but, so far, polymuds with distinctive syndepositional cavities and a vertical zonation into grain assemblage zones is not documented. The Longdianshan Hill Waulsortian‐like carbonate mud banks significantly enlarge the spectrum of Mississippian buildups in South China, which on a global scale is still relatively poor. Copyright © 2012 John Wiley & Sons, Ltd.
Elevated histone acetylations in Müller cell contribute to inflammation: A novel inhibitory effect of minocycline
Authors: Wang Lei‐Lei , Chen Hong , Huang Kun , Zheng Ling
Published: August 2012

Inflammation plays important roles in the development of diabetic retinopathy (DR). How Müller cells contribute to DR‐related inflammation remains unclear. We hypothesized that under diabetic conditions, elevated histone acetylations in Müller cells contribute to the inflammatory response. In this study, significantly increased histone acetylations, elevated histone acetyltranferases levels, and decreased histone deacetylases levels were found in the retinas of diabetic rats. Elevated AcH3K9 and AcH3K18 were partially co‐stained with Müller cells on retinal sections by immunofluorescence staining. Consistently, high‐glucose (HG) treated rMC‐1 cells, a Müller cell line, also showed upregulation of acetylated histones, accompanied with the overexpression of GFAP, p‐STAT3, and NFκB‐p65, and two inflammatory genes, TNFα and MCP‐1. Meanwhile, sodium butyrate (NaB)‐induced upregulation of acetylated histones is also accompanied with transcription of inflammatory genes. Minocycline, a drug with beneficial effects on DR, was found to downregulate HG‐induced Müller cell activation, inflammation, and acetylated H3K18 bound to the promoters of GFAP and inflammatory genes by chromatin immunoprecipitation assay. Furthermore, the effects of minocycline on HG‐induced elevation in histone acetylations were also demonstrated in isolated primary rat Müller cells. These findings suggest the elevation of histone acetylations in Müller cells plays important regulating roles in the inflammatory response during diabetic conditions. Inhibition of histone acetylation by minocycline is a novel function that may contribute to its beneficial effects on DR. © 2012 Wiley Periodicals, Inc.
Paranoid symptoms and hallucinations among the older people in Western Europe
Authors: Östling Svante , Bäckman Kristoffer , Waern Margda , Marlow Thomas , Braam Arjan W. , Fichter Manfred , Lawlor Brian A. , Lobos Antonio , Reischies Friedel M. , Copeland John R. M. , Skoog Ingmar
Published: August 2012

Objective

It is not clear whether the prevalence of psychosis increases with age. We studied the age‐specific prevalence of psychotic symptoms in older people in Western Europe.

Methods

Older people without dementia (age 65–104 years, N = 8762) from the western part of Europe in the EURODEP concerted action took part in psychiatric examinations.

Results

In total, 2.4% of the men and 2.9% of the women had psychotic symptoms. Using a multilevel logistic regression model that included gender and age as a continuous variable, we found that a 5‐year increase in age increased the prevalence of psychotic symptoms (odds ratio 1.2 95% confidence interval 1.06–1.3, p = 0.001). A second multilevel regression model showed that wishing to be dead, depressed mood, functional disability, not being married and cognitive impairment measured with Mini mental state examination were all associated with psychotic symptoms whereas gender was not.

Conclusion

The prevalence of psychotic symptoms in non‐demented older people increases with age, and these symptoms are associated with other psychopathology, social isolation and problems with daily living. Copyright © 2012 John Wiley & Sons, Ltd.
Obesity and fast food in urban markets: a new approach using geo‐referenced micro data
Authors: Chen Susan Elizabeth , Florax Raymond J. , Snyder Samantha D.
Published: August 2012

This paper presents a new method of assessing the relationship between features of the built environment and obesity, particularly in urban areas. Our empirical application combines georeferenced data on the location of fast‐food restaurants with data about personal health, behavioral, and neighborhood characteristics. We define a ‘local food environment’ for every individual utilizing buffers around a person's home address. Individual food landscapes are potentially endogenous because of spatial sorting of the population and food outlets, and the body mass index (BMI) values for individuals living close to each other are likely to be spatially correlated because of observed and unobserved individual and neighborhood effects. The potential biases associated with endogeneity and spatial correlation are handled using spatial econometric estimation techniques. Our application provides quantitative estimates of the effect of proximity to fast‐food restaurants on obesity in an urban food market. We also present estimates of a policy simulation that focuses on reducing the density of fast‐food restaurants in urban areas. In the simulations, we account for spatial heterogeneity in both the policy instruments and individual neighborhoods and find a small effect for the hypothesized relationships between individual BMI values and the density of fast‐food restaurants. Copyright © 2012 John Wiley & Sons, Ltd.
Positive cardiac inotropic effect of albumin infusion in rodents with cirrhosis and ascites: molecular mechanisms
Authors: Bortoluzzi Alessia , Ceolotto Giulio , Gola Elisabetta , Sticca Antonietta , Bova Sergio , Morando Filippo , Piano Salvatore , Fasolato Silvano , Rosi Silvia , Gatta Angelo , Angeli Paolo
Published: August 2012

The aim of this study was to evaluate the effect and molecular mechanism of albumin infusion on cardiac contractility in experimental cirrhosis with ascites. Cardiac contractility was recorded ex vivo in rats with cirrhosis and ascites and in control rats after the injection in the caudal vein of albumin, saline, or hydroxyethyl starch (HES). Gene and protein expression of β-receptors and pathways involved in their intracellular signaling such as Gαi2 protein (Gαi2), adenylate cyclase 3 (Adcy3), protein expression of tumor necrosis factor alpha (TNF-α) and inducible nitric oxide synthase (iNOS), were evaluated in cardiac tissue in both groups. Phosphorylation and membrane-translocation of the cytosolic components of nicotinamide adenine dinucleotide phosphate (NAD(P)H)-oxidase and translocation of nuclear factor kappa B (NF-κB) were also evaluated. After saline intravenous injection, cardiac contractility was significantly reduced in rats with cirrhosis as compared to control rats (P < 0.01). This was associated with: (1) increased expression of protein Gαi2 (P < 0.05), TNF-α (P < 0.05), iNOS (P < 0.05); (2) increased NAD(P)H-oxidase activity (P < 0.05); (3) increased nuclear translocation of NF-κB (P < 0.05); and (4) lower expression of Adcy 3 (P < 0.05) in cardiac tissue of rats with cirrhosis. After albumin injection cardiac contractility (P < 0.01), protein expression of TNF-α, iNOS, Gαi2, and Adcy3, NAD(P)H-oxidase activity and nuclear translocation of NF-κB in cardiac tissue of rats with cirrhosis were reversed to control levels (P < 0.05). HES injection did not modify cardiac contractility and nuclear translocation of NF-κB in cardiac tissue of rats with cirrhosis. Conclusion: Albumin exerts a positive cardiac inotropic effect in rats with cirrhosis and ascites counteracting the negative effects of oxidative stress- and TNF-α-induced activation of NF-κB-iNOS pathway and oxidative stress-induced alteration of β-receptor signaling. (Hepatology 2013)
Adoptive transfer of ex vivo expanded regulatory T cells in an autoimmune hepatitis murine model restores peripheral tolerance
Authors: Lapierre Pascal , Béland Kathie , Yang Roland , Alvarez Fernando
Published: August 2012

Autoimmune hepatitis (AIH) is characterized by a loss of immunological tolerance to hepatocytes. Patients respond well to immunosuppression but progression to endstage liver disease occurs in 10%-20% of cases, leading to liver transplantation. Using a murine model of type 2 AIH, we identified susceptibility factors for autoimmune hepatitis and attempted to restore immunological tolerance to liver autoantigens. An increased ectopic expression of a liver autoantigen (FTCD) in the thymus leading to reduced numbers of circulating autoreactive T cells was sufficient to prevent development of AIH in mice. However, in the presence of a reduced central tolerance to FTCD, a strong regulatory T-cell response was able to inhibit proliferation of liver-specific autoreactive T cells and prevent AIH. Development of a severe AIH stemmed from reduced numbers of functional regulatory T cell (Tregs) leading to an increased proliferation of FTCD-specific autoreactive T and B cells. Adoptive transfer of ex vivo expanded CXCR3+ Tregs in mice with AIH efficiently targeted the inflamed liver, restored peripheral tolerance to FTCD, and induced remission of AIH. Conclusion: Peripheral tolerance to liver autoantigens in AIH is paramount. Autologous infusion of ex vivo expanded CXCR3+ Tregs in AIH patients could be an effective therapeutic approach to restore peripheral tolerance and induce remission of AIH. (Hepatology 2013)
In vivocorrosion mechanism by elemental interdiffusion of biodegradable Mg–Ca alloy
Authors: Jung Jae‐Young , Kwon Sang‐Jun , Han Hyung‐Seop , Lee Ji‐Young , Ahn Jae‐Pyoung , Yang Seok‐Jo , Cho Sung‐Youn , Cha Pil‐Ryung , Kim Yu‐Chan , Seok Hyun‐Kwang
Published: August 2012

We elucidated thein vivocorrosion mechanism of the biodegradable alloy Mg–10 wt % Ca in rat femoral condyle through transmission electron microscope observations assisted by focused ion beam technique. The alloy consists of a primary Mg phase and a three‐dimensional lamellar network of Mg and Mg2Ca. We found that the Mg2Ca is rapidly corroded by interdiffusion of Ca and O, leading to a structural change from lamellar network to nanocrystalline MgO. In contrast to the fast corrosion rate of the lamellar structure, the primary Mg phase slowly changes into nanocrystalline MgO through surface corrosion by O supplied along the lamellar networks. The rapid interdiffusion induces an inhomogeneous Ca distribution and interestingly leads to the formation of a transient CaO phase, which acts as a selective leaching path for Ca. In addition, the outgoing Ca with P from body fluids forms needle‐type calcium phosphates similar to hydroxyl apatite at interior and surface of the implant, providing an active biological environment for bone mineralization. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2012.
Quantitative ultrasound of cortical bone in the femoral neck predicts femur strength: Results of a pilot study
Authors: Grimal Quentin , Grondin Julien , Guérard Sandra , Barkmann Reinhard , Engelke Klaus , Glüer Claus-C , Laugier Pascal
Published: August 2012

A significant risk of femoral neck (FN) fracture exists for men and women with an areal bone mineral density (aBMD) higher than the osteoporotic range, as measured with dual-energy X-ray absorptiometry (DXA). Separately measuring the cortical and trabecular FN compartments and combining the results would likely be a critical aspect of enhancing the diagnostic capabilities of a new technique. Because the cortical shell determines a large part of FN strength a novel quantitative ultrasound (QUS) technique that probes the FN cortical compartment was implemented. The sensitivity of the method to variations of FN cortical properties and FN strength was tested. Nine femurs (women, mean age 83 years) were subjected to QUS to measure the through transmission time-of-flight (TOF) at the FN and mechanical tests to assess strength. Quantitative computed tomography (QCT) scans were performed to enable analysis of the dependence of TOF on bone parameters. DXA was also performed for reference. An ultrasound wave propagating circumferentially in the cortical shell was measured in all specimens. Its TOF was not influenced by the properties of the trabecular compartment. Averaged TOF for nine FN measurement positions/orientations was significantly correlated to strength (R2 = 0.79) and FN cortical QCT variables: total BMD (R2 = 0.54); regional BMD in the inferoanterior (R2 = 0.90) and superoanterior (R2 = 0.57) quadrants; and moment of inertia (R2 = 0.71). The results of this study demonstrate that QUS can perform a targeted measurement of the FN cortical compartment. Because the method involves mechanical guided waves, the QUS variable is related to the geometric and material properties of the cortical shell (cortical thickness, tissue elasticity, and porosity). This work opens the way to a multimodal QUS assessment of the proximal femur, combining our approach targeting the cortical shell with the existing modality sensitive to the trabecular compartment. In vivo feasibility of our approach has to be confirmed with experimental data in patients. © 2013 American Society for Bone and Mineral Research
Fast force field‐based optimization of protein–ligand complexes with graphics processor
Authors: Heinzerling Lennart , Klein Robert , Rarey Matthias
Published: August 2012

Usually based on molecular mechanics force fields, the post‐optimization of ligand poses is typically the most time‐consuming step in protein–ligand docking procedures. In return, it bears the potential to overcome the limitations of discretized conformation models. Because of the parallel nature of the problem, recent graphics processing units (GPUs) can be applied to address this dilemma. We present a novel algorithmic approach for parallelizing and thus massively speeding up protein–ligand complex optimizations with GPUs. The method, customized to pose‐optimization, performs at least 100 times faster than widely used CPU‐based optimization tools. An improvement in Root‐Mean‐Square Distance (RMSD) compared to the original docking pose of up to 42% can be achieved. © 2012 Wiley Periodicals, Inc.
The barbel‐like specialization of the pelvic fins in Ophidion rochei (Ophidiidae)
Authors: Codina Elisabet , Loïc Kéver , Compère Philippe , Dragičević Branko , Dulčić Jakov , Parmentier Eric
Published: August 2012

Pelvic fins in Ophidion rochei are reduced to four rod‐like structures situated at the ventral jaws. While the fish is swimming, they make continuous sweeping movements on the bottom. This paper examines and describes the anatomy of the pelvic fins to determine the possible functions of these appendages in relation to the mode of life of this fish species. The pelvic fins of O. rochei show strong similarities with barbels because they have identical sensory cell types, (taste buds, solitary chemosensory cells, and goblet cells), innervations and sensory function. Having nocturnal habits, specialization of pelvic fins in O. rochei corresponds to a supporting role to the life in dark environment. J. Morphol., 2012. © 2012 Wiley Periodicals, Inc.
Entrepreneurship and innovation: Overview
Authors: O'Regan Nicholas
Published: August 2012

Product and process innovation are well established and now the attention is turning to value co‐creation.
Customer‐supplier relationships during the process of innovation: An innovation systems approach
Authors: Phillips Wendy , Lamming Richard , Caldwell Nigel
Published: August 2012

Within an innovation system, institutions may contain the ability not only to support but also to restrain the coordination of knowledge and skills in inter‐organizational relationships.
An in‐cell capacitive touch sensor integrated in an LTPS WSVGA TFT‐LCD
Authors: Tomita Satoru , Okada Takashi , Takahashi Hideyuki
Published: August 2012

This paper discusses an In‐cell capacitive touch sensor and its integration in an LTPS TFT‐LCD with 7‐inch screen size and WSVGA resolution. The operation of the newly developed sensor is based on capacitive coupling between user's finger and the detection electrode on the TFT substrate, and is purely capacitive. The sensors and the sensor driver circuits have been integrated in the TFT substrate of the prototype TFT‐LCD using LTPS technology. The prototype having 256x150 sensors shows advantages such as smooth operation with no touch force, high position accuracy, multi‐touch (10 or more), a thin and light LCD module, high display quality, and thus is suitable for various applications such as cell‐phones, smart‐phones, mobile‐PCs, and automotive‐use displays.
Benign paroxysmal positional vertigo accompanied by sudden sensorineural hearing loss: A comparative study with idiopathic benign paroxysmal positional vertigo
Authors: Kim Min‐Beom , Ban Jae Ho
Published: August 2012

Objectives/Hypothesis:

To investigate the clinical characteristics of benign paroxysmal positional vertigo (BPPV) associated with idiopathic sudden sensorineural hearing loss (ISSHL) and to compare them with the characteristics of idiopathic BPPV (i‐BPPV).

Study Design:

Retrospective case series.

Methods:

We retrospectively analyzed 519 patients with ISSHL and 597 patients with i‐BPPV. The ISSHL patients with recent vertigo history before or after admission were tested with video‐nystagmography that included the caloric test. BPPV with same‐side ISSHL was identified and categorized as secondary BPPV (s‐BPPV) using the roll or Dix‐Hallpike test. All members of the s‐BPPV and i‐BPPV groups underwent a daily canalith repositioning procedure (CRP) during the admission periods. We investigated the clinical characteristics, including the number of CRPs performed to achieve successful reposition, canal involvement type, and effect of canal paresis and made comparisons between the s‐BPPV and i‐BPPV groups.

Results:

Of the 519 ISSHL patients, 63 (12.1%) were identified as having s‐BPPV. Multicanal involvement was more frequent in s‐BPPV than i‐BPPV patients (P < .001). The mean number of CRPs needed to achieve successful reposition was 4.28 in s‐BPPV and 1.34 in i‐BPPV (P < .001). The presence of canal paresis was also associated with a greater number of CRPs required for s‐BPPV (P < .02).

Conclusions:

In about 12% of ISSHL patients, s‐BPPV was concurrent. More CRPs were required for successful repositioning in patients with s‐BPPV than in patients with i‐BPPV. Also, the presence of canal paresis in s‐BPPV was associated with a greater number of required CRPs. Laryngoscope, 2012
Hofmeister Salt Effects on the LCST Behavior of Poly(2‐Oxazoline) Star Ionomers
Authors: ten Brummelhuis Niels , Secker Christian , Schlaad Helmut
Published: August 2012

Effects of pH, ionic strength, and type of salt (variation of anions) on the cloud‐point temperature (TCP) of thermoresponsive poly(2‐ethyl‐2‐oxazoline) star ionomers are investigated. TCPs can be varied in a wide range, from 10 to >95 °C, corresponding with the Hofmeister series and the ionization of the core. Addition of salt weakens the influence of pH. For star copolymer with an amine core similar trends are observed as for star copolymers with a carboxylic acid core, although the presence of a chaotropic salt affords an inversion of the effect of pH, that is, TCPs are lowest at pH 3, where the amine groups are fully protonated. This effect is likely due to the specific binding of chaotropic anions to the amine and ammonium groups, which is not observed for carboxylic acid groups.
The vibration rheometer: the effect of vibration on fresh concrete and similar materials
Authors: Juradin S. , Krstulovic P.
Published: August 2012

The use of the newly‐designed electronic accelerometer as an integral part of the vibration rheometer, for the first time made it possible to continuously and accurately record the acceleration of an apparatus piston as a solid mass oscillating in the test specimen of the material under sub‐base excitation. The research is focused on plastic concrete, mortar and appropriate reference materials whose behavior was approximated to a pseudoplastic fluid. An analytical solution to the oscillation of the piston in the specimen is also provided. The research showed that a layer of the material with the properties close to the ideal Newtonian fluid forms around each particle exceeding 0.25 mm causing a reduction in resistance to deformation and compression in a specimen. The effect of vibrations on plastic concrete and similar materials is also described.
Analysis of the compression process and dimensional optimization of self‐expanding stent of a nickel titanium alloy
Authors: Wang X. M. , Zhou Q. T. , Liu H. , Li L. , Deng C. H.
Published: August 2012

The vascular stents are important devices introduced into the vessel to protect the lumen from unfriendly stenosis so that the blood can flow naturally. During its implantation to the vessel, the stent should be compressed to a delivery system with very small dimension to accomplish the minimal invasive operation. At this stage, the stent will withstand very large stresses which will cause large damages in the structure. In this paper, the compression process of the stent was analyzed by finite element analysis method with software ABAQUS. The stress, strain and martensite volume fraction distributions were investigated at the end compression. Results show that the stent fillets are the dangerous areas for the potential failure. Subsequently, the dimensional optimization was performed to decrease the maximum concentration stress. After the optimization, the maximum stress can be decreased by 14.2%, which means the stent's work life can be increased.
Rapid quantification of oxygen tension in blood flow with a fluorine nanoparticle reporter and a novel blood flow‐enhanced‐saturation‐recovery sequence
Authors: Hu Lingzhi , Chen Junjie , Yang Xiaoxia , Caruthers Shelton D. , Lanza Gregory M. , Wickline Samuel A.
Published: August 2012

We present a novel blood flow‐enhanced‐saturation‐recovery (BESR) sequence, which allows rapid in vivo T1 measurement of blood for both 1H and 19F nuclei. BESR sequence is achieved by combining homogeneous spin preparation and time‐of‐flight image acquisition and therefore preserves high time efficiency and signal‐to‐noise ratio for 19F imaging of circulating perfluorocarbon nanoparticles comprising a perfluoro‐15‐crown‐5‐ether core and a lipid monolayer (nominal size = 250 nm). The consistency and accuracy of the BESR sequence for measuring T1 of blood was validated experimentally. With a confirmed linear response feature of 19F R1 with oxygen tension in both salt solution and blood sample, we demonstrated the feasibility of the BESR sequence to quantitatively determine the oxygen tension within mouse left and right ventricles under both normoxia and hyperoxia conditions. Thus, 19F BESR MRI of circulating perfluorocarbon nanoparticles represents a new approach to noninvasively evaluate intravascular oxygen tension. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.
Spatially selective implementation of the adiabatic T2prep sequence for magnetic resonance angiography of the coronary arteries
Authors: Soleimanifard Sahar , Schär Michael , Hays Allison G. , Prince Jerry L. , Weiss Robert G. , Stuber Matthias
Published: August 2012

In coronary magnetic resonance angiography, a magnetization‐preparation scheme for T2‐weighting (T2Prep) is widely used to enhance contrast between the coronary blood‐pool and the myocardium. This prepulse is commonly applied without spatial selection to minimize flow sensitivity, but the nonselective implementation results in a reduced magnetization of the in‐flowing blood and a related penalty in signal‐to‐noise ratio. It is hypothesized that a spatially selective T2Prep would leave the magnetization of blood outside the T2Prep volume unaffected and thereby lower the signal‐to‐noise ratio penalty. To test this hypothesis, a spatially selective T2Prep was implemented where the user could freely adjust angulation and position of the T2Prep slab to avoid covering the ventricular blood‐pool and saturating the in‐flowing spins. A time gap of 150 ms was further added between the T2Prep and other prepulses to allow for in‐flow of a larger volume of unsaturated spins. Consistent with numerical simulation, the spatially selective T2Prep increased in vivo human coronary artery signal‐to‐noise ratio (42.3 ± 2.9 vs. 31.4 ± 2.2, n = 22, P < 0.0001) and contrast‐to‐noise‐ratio (18.6 ± 1.5 vs. 13.9 ± 1.2, P = 0.009) as compared to those of the nonselective T2Prep. Additionally, a segmental analysis demonstrated that the spatially selective T2Prep was most beneficial in proximal and mid segments where the in‐flowing blood volume was largest compared to the distal segments. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.
Epigenetics: new views on understanding and treating addiction
Authors: Greener Mark
Published: August 2012

Recent research in the field of epigenetics is helping us to understand more about the mechanisms involved in drug addiction and why it tends to persist throughout life. This may ultimately lead to the discovery of new treatments. Mark Greener reports.
Employment status and quality of life in recently diagnosed breast cancer survivors
Authors: Timperi Allegra W. , Ergas Isaac Joshua , Rehkopf David H. , Roh Janise M. , Kwan Marilyn L. , Kushi Lawrence H.
Published: August 2012

Background

Breast cancer survivors are less likely to be employed than similar healthy women, yet effects of employment on the well being of survivors are largely unknown. In a prospective cohort study of 2013 women diagnosed from 2006 to 2011 with invasive breast cancer in Kaiser Permanente Northern California, we describe associations between hours worked per week and change in employment with quality of life (QOL) from diagnosis through active treatment.

Methods

Participants completed information on employment status and QOL approximately 2 and 8 months post‐diagnosis. QOL was assessed by the Functional Assessment of Cancer Therapy—Breast Cancer. Multivariable linear regression models were adjusted for potential confounders including demographic, diagnostic, and medical care factors to examine associations between employment and QOL.

Results

At baseline, overall well being was higher for women who worked at least some hours per week compared with women who were not working. Women working 1–19 h/week at baseline also had higher functional well being compared with women who were not working. There was a significant, positive association between hours worked per week and physical and social well being. At the 6‐month follow‐up, women working at least 20 h/week had higher physical and functional well being than those who were not working. Lower scores for physical and functional well being were observed among women who stopped working during the 6‐month follow‐up period.

Conclusions

Continuing to work after a breast cancer diagnosis may be beneficial to multiple areas of QOL. Strategies to help women continue working through treatment should be explored. Copyright © 2012 John Wiley & Sons, Ltd.
Posttraumatic stress in infants and preschoolers with cancer
Authors: Graf Anna , Bergstraesser Eva , Landolt Markus A.
Published: August 2012

Objective

This study is the first to assess posttraumatic stress disorder (PTSD) in young children with cancer and to examine individual, medical, and parent‐related determinants.

Methods

Forty‐eight patients with cancer, ages 8–48 months, were assessed in an average of 15 months after their diagnosis, using mothers as informants to complete the Posttraumatic Stress Disorder Semi‐Structured Interview and Observational Record for Infants and Young Children. Additionally, mothers and the attending pediatric oncologist completed questionnaires on various determinants of child PTSD.

Results

Nine children (18.8%) met the age‐appropriate criteria for full PTSD proposed by Scheeringa et al., and 20 children (41.7%) met criteria for partial PTSD. Multivariate logistic regression analysis revealed that higher child age at diagnosis (odds ratio = 1.11) and maternal PTSD severity (odds ratio = 1.14) increased the risk of full or partial PTSD in children.

Conclusions

This study provides evidence for a substantial prevalence of PTSD in young children with cancer and identifies important risk factors. Copyright © 2012 John Wiley & Sons, Ltd.
Thermal unfolding of the N‐terminal region of p53 monitored by circular dichroism spectroscopy
Authors: Schaub Leasha J. , Campbell James C. , Whitten Steven T.
Published: August 2012

It has been estimated that 30% of eukaryotic protein and 70% of transcription factors are intrinsically disordered (ID). The biochemical significance of proteins that lack stable tertiary structure, however, is not clearly understood, largely owing to an inability to assign well‐defined structures to specific biological tasks. In an attempt to investigate the structural character of ID protein, we have measured the circular dichroism spectrum of the N‐terminal region of p53 over a range of temperatures and solution conditions. p53 is a well‐studied transcription factor that has a proline‐rich N‐terminal ID region containing two activation domains. High proline content is a property commonly associated with ID, and thus p53 may be a good model system for investigating the biochemical importance of ID. The spectra presented here suggest that the N‐terminal region of p53 may adopt an ordered structure under physiological conditions and that this structure can be thermally unfolded in an apparent two‐state manner. The midpoint temperature for this thermal unfolding of the N‐terminal region of p53 was at the near‐physiological temperature of 39°C, suggesting the possibility of a physiological role for the observed structural equilibrium.
Three intrinsically unstructured mussel adhesive proteins, mfp‐1, mfp‐2, and mfp‐3: Analysis by circular dichroism
Authors: Hwang Dong Soo , Waite J. Herbert
Published: August 2012

Mussel foot proteins (mfps) mediate fouling by the byssal holdfast and have been extensively investigated as models for versatile polymer‐mediated underwater adhesion and coatings. However, insights into the structural properties of mfps have lagged far behind the nanomechanical advances, owing in part to the inability of these proteins to crystallize as well as their limited solubility. Here, solution secondary structures of mfp‐1, mfp‐2, and mfp‐3, localized in the mussel byssal cuticle, adhesive plaque, and plaque–substratum interface, respectively, were investigated using circular dichroism. All three have significant extended coil solution structure, but two, mfp‐1 and mfp‐2, appear to have punctuated regions of structure separated by unstructured domains. Apart from its punctuated distribution, the structure in mfp‐1 resembles other structural proteins such as collagen and plant cell‐wall proteins with prominent polyproline II helical structure. As in collagen, PP II structure of mfp‐1 is incrementally disrupted by increasing the temperature and by raising pH. However, no recognizable change in mfp‐1's PP II structure was evident with the addition with Ca2+ and Fe3+. In contrast, mfp‐2 exhibits Ca2+‐ and disulfide‐stabilized epidermal growth factor‐like domains separated by unstructured sequence. Mfp‐2 showed calcium‐binding ability. Bound calcium in mfp‐2 was not removed by chelation at pH 5.5, but it was released upon reduction of disulfide bonds. Mfp‐3, in contrast, appears to consist largely of unstructured extended coils.
Application of the parallel line assay to assessment of biosimilar products based on binary endpoints
Authors: Lin Jr‐Rung , Chow Shein‐Chung , Chang Chih‐Hsi , Lin Ya‐Ching , Liu Jen‐pei
Published: August 2012

Biological drug products are therapeutic moieties manufactured by a living system or organisms. These are important life‐saving drug products for patients with unmet medical needs. Because of expensive cost, only a few patients have access to life‐saving biological products. Most of the early biological products will lose their patent in the next few years. This provides the opportunity for generic versions of the biological products, referred to as biosimilar drug products. The US Biologic Price Competition and Innovation Act passed in 2009 and the draft guidance issued in 2012 provide an approval pathway for biological products shown to be biosimilar to, or interchangeable with, a Food and Drug Administration‐licensed reference biological product. Hence, cost reduction and affordability of the biosimilar products to the average patients may become possible. However, the complexity and heterogeneity of the molecular structures, complicated manufacturing processes, different analytical methods, and possibility of severe immunogenicity reactions make evaluation of equivalence between the biosimilar products and their corresponding reference product a great challenge for statisticians and regulatory agencies. To accommodate the stepwise approach and totality of evidence, we propose to apply a parallel assay to evaluate the extrapolation of the similarity in product characteristics such as doses or pharmacokinetic responses to the similarity in binary efficacy endpoints. We also report the results of simulation studies to evaluate the performance, in terms of size and power, of our proposed methods. We present numerical examples to illustrate the suggested procedures. Copyright © 2012 John Wiley & Sons, Ltd.
A weighted generalized score statistic for comparison of predictive values of diagnostic tests
Authors: Kosinski Andrzej S.
Published: August 2012

Positive and negative predictive values are important measures of a medical diagnostic test performance. We consider testing equality of two positive or two negative predictive values within a paired design in which all patients receive two diagnostic tests. The existing statistical tests for testing equality of predictive values are either Wald tests based on the multinomial distribution or the empirical Wald and generalized score tests within the generalized estimating equations (GEE) framework. As presented in the literature, these test statistics have considerably complex formulas without clear intuitive insight. We propose their re‐formulations that are mathematically equivalent but algebraically simple and intuitive. As is clearly seen with a new re‐formulation we presented, the generalized score statistic does not always reduce to the commonly used score statistic in the independent samples case. To alleviate this, we introduce a weighted generalized score (WGS) test statistic that incorporates empirical covariance matrix with newly proposed weights. This statistic is simple to compute, always reduces to the score statistic in the independent samples situation, and preserves type I error better than the other statistics as demonstrated by simulations. Thus, we believe that the proposed WGS statistic is the preferred statistic for testing equality of two predictive values and for corresponding sample size computations. The new formulas of the Wald statistics may be useful for easy computation of confidence intervals for difference of predictive values. The introduced concepts have potential to lead to development of the WGS test statistic in a general GEE setting. Copyright © 2012 John Wiley & Sons, Ltd.
Re: Can angle of progression in pregnant women before onset of labor predict mode of delivery? R. Levy, S. Zaks, A. Ben‐Arie, S. Perlman, Z. Hagay and E. Vaisbuch. Ultrasound Obstet Gynecol 2012; 40: 332–337.
Authors: Iliescu D.
Published: August 2012

Linked Comment: Ultrasound Obstet Gynecol 2012:40:332–337
Accident prevention in day-to-day clinical radiation therapy practice
Authors: Baeza M.
Published: August 2012

Nearly 50–60% of cancer patients will undergo radiotherapy at some point in their treatment. Around 85% of the world's population live in developing countries served by approximately 30% of the world's radiotherapy facilities. It has been suggested that 1 megavoltage unit is required for every 500 new treatment courses per year, while others estimate that 1 megavoltage unit is needed for every 300 new treatments. However, these numbers do not necessarily take into account the development of new technologies and treatment modalities, which are more time- and resource-intensive. The International Commission on Radiological Protection has emphasised that ‘purchasing new equipment without a concomitant effort on education and training and on a programme of quality assurance is dangerous’, and ‘the decision to implement a new technology for radiation therapy should be based on a thorough evaluation of the expected benefits, rather than being driven by the technology itself’. It is estimated that the rate of serious mistakes could be as high as 0.2%, which is several orders of magnitude higher than the rate reported for commercial aviation. So, how safe is safe? It can be stated that the development of a culture of safety is critical and requires efforts in education and training, which could prove difficult in overloaded departments.
Effective dose and risks from medical x-ray procedures
Authors: Balonov M.I. , Shrimpton P.C.
Published: August 2012

The radiation risks from a range of medical x-ray examinations (radiography, fluoroscopy, and computed tomography) were assessed as a function of the age and sex of the patient using risk models described in Publication 103 (ICRP, 2007) and UNSCEAR (2006, Annex A). Such estimates of risk based on typical organ doses were compared with those derived from effective doses using the International Commission on Radiological Protection's nominal risk coefficients. Methodologically similar but not identical dose and risk calculations were performed independently at the Institute of Radiation Hygiene (Russia) and the Health Protection Agency (UK), and led to similar conclusions. The radiogenic risk of stochastic health effects following various x-ray procedures varied significantly with the patient's age and sex, but to differing degrees depending on which body organs were irradiated. In general, the risks of radiation-induced stochastic health effects in children are estimated to be higher (by a factor of ⩽4) than in adults, and risks in senior patients are lower by a factor of ⩾10 relative to younger people. If risks are assessed on the basis of effective dose, they are underestimated for children of both sexes by a factor of ⩽4. This approach overestimates risks by a factor of ⩽3 for adults and about an order of magnitude for senior patients. The significant sex and age dependence of radiogenic risk for different cancer types is an important consideration for radiologists when planning x-ray examinations. Whereas effective dose was not intended to provide a measure of risk associated with such examinations, it may be sufficient to make simple adjustments to the nominal risk per unit effective dose to account for age and sex differences.
Minimising medically unwarranted computed tomography scans
Authors: Brenner D.J.
Published: August 2012

As computed tomography (CT) is such a superb diagnostic tool and individual CT risks are small, whenever a CT scan is clinically warranted, the CT benefit/risk balance is by far in the patient's favour. However, if a CT scan is not clinically warranted, this balance shifts dramatically. It is likely that at least 25% of CT scans fall into this latter category, in that they could either be replaced with alternative imaging modalities or could be avoided entirely. Use of clinical decision rules for CT usage represents a powerful approach for slowing down the increase in CT usage, because they have the potential to overcome some of the major factors that result in some CT scans being undertaken when they may not be clinically helpful.
NORM Management in the oil and gas industry
Authors: Cowie M. , Mously K. , Fageeha O. , Nassar R.
Published: August 2012

It has been established that naturally occurring radioactive material (NORM) may accumulate at various locations along the oil and gas production process. Components such as wellheads, separation vessels, pumps, and other processing equipment can become contaminated with NORM, and NORM can accumulate in the form of sludge, scale, scrapings, and other waste media. This can create a potential radiation hazard to workers, the general public, and the environment if certain controls are not established. Saudi Aramco has developed NORM management guidelines, and is implementing a comprehensive strategy to address all aspects of NORM management that aim to enhance NORM monitoring; control of NORM-contaminated equipment; control of NORM waste handling and disposal; and protection, awareness, and training of workers. The benefits of shared knowledge, best practice, and experience across the oil and gas industry are seen as key to the establishment of common guidance. This paper outlines Saudi Aramco's experience in the development of a NORM management strategy, and its goals of establishing common guidance throughout the oil and gas industry.
Radiation transport calculations for cosmic radiation
Authors: Endo A. , Sato T.
Published: August 2012

The radiation environment inside and near spacecraft consists of various components of primary radiation in space and secondary radiation produced by the interaction of the primary radiation with the walls and equipment of the spacecraft. Radiation fields inside astronauts are different from those outside them, because of the body's self-shielding as well as the nuclear fragmentation reactions occurring in the human body. Several computer codes have been developed to simulate the physical processes of the coupled transport of protons, high-charge and high-energy nuclei, and the secondary radiation produced in atomic and nuclear collision processes in matter. These computer codes have been used in various space radiation protection applications: shielding design for spacecraft and planetary habitats, simulation of instrument and detector responses, analysis of absorbed doses and quality factors in organs and tissues, and study of biological effects. This paper focuses on the methods and computer codes used for radiation transport calculations on cosmic radiation, and their application to the analysis of radiation fields inside spacecraft, evaluation of organ doses in the human body, and calculation of dose conversion coefficients using the reference phantoms defined in ICRP Publication 110.