bluuebunny/crossref_metadata_2025 huggingface dataset:
Nonlinear Propagation in the Vicinity of a Small Acoustic Source
Authors: Otani Takahiko
Published: March 2014

Even though an infinitesimal spherical acoustic wave propagates in the vicinity of a small source or a point source, an extremely high amplitude wave must be observed in the vicinity of that source. An analytical expression of nonlinear propagation in the near field of a point source or a small spherical source is derived herein.
Various Aspects of Ultrasonic Light-Diffraction and Domains of Parameters Pertaining to These Aspects
Authors: Nomoto Otohiko
Published: March 2014

Various aspects of the ultrasonic light-diffraction phenomenon, including the Bragg reflection, Raman-Nath diffraction, and ray-optica aspect like mirror-type Bragg reflection up to higher order spectra are discussed in relation to their model mechanisms and the domains of parameters producing them.
Measurement of Complex Adiabatic Compressibility of Liquids in the Low Frequency Range
Authors: Tanaka Hajime , Nishi Toshio , Wada Yasaku
Published: March 2014

A new method for measuring complex adiabatic compressibility of liquids in the low frequency range from 0.5 Hz to 2 kHz is presented. Possibility of extension of the frequency range of the methods is discussed. The method is applicable to the study of the low-frequency relaxational behavior of liquids such as critical mixtures, liquid crystals, gels, and biological solutions.
Ultrasonic Properties of Melittin Solution
Authors: Kagayama Toshi , Kataoka Ryoichi , Mitaku Shigeki
Published: March 2014

Melittin undergoes structural change from monomeric random coil to tetrameric helices according to various conditions. The ultrasonic properties of melittin solution were measured as a function of the frequency, the temperature, pH and the concentration. There was no ultrasonic relaxation nor anomaly of temperature dependence. When pH was varied, ultrasonic velocity showed a significant change due to the helix-coil transition accompanied by aggregation. The concentration dependence of the ultrasonic velocity was nonlinear, from which the mechanism of the aggregation was discussed.
Anharmonic Properties of Ultrasounds in Diamond-Type Crystals and Quartz Plate under an Intense Exicitation
Authors: Abe Yutaka , Imai Kazuaki
Published: March 2014

The harmonic generation due to the third-order elastic (TOE) constants in germanium and gallium arsenide, and the nonlinear current-jump effect due to the fourth-order elastic constants in a quartz plate have been investigated. The complete TOE constants were determined from the measurement using an optical interferometer and from the values derived from the valence-force field theory. They showed a good agreement with those obtained by other experimental techniques. A phenomenon analogous to the hybride optical bistability was observed in a thickness-shear mode quartz resonator, and this was analyzed in terms of an equivalent nonlinear network.
Parametric Receiving Array as a Practical Sound Receiver
Authors: Tsuchiya Takao , Watanabe Yoshiaki , Urabe Yasumasa
Published: March 2014

A theoretical approach based on the nonlinear effect for the propagation velocity is presented to express the receiving mechanism of the parametric receiving array. The parameter of the nonlinearity is treated exactly. The parametric microphone is realized using 40 kHz pump wave and 2 m array length, and the observed results show good agreement with the theoretical results. The effect of the medium turbulence on the SNR of the system is improved using a wind screen. It is recognized through experiments that the parametric microphone can be applied as a practical sound receiver.
Protons Safely Allow Coverage of High-Risk Nodes for Patients with Regionally Advanced Non-Small-Cell Lung Cancer
Authors: Nichols R. C. , Huh S. H. , Hoppe B. S. , Henderson R. H. , Li Z. , Flampouri S. , D'Agostino H. J. , Cury J. D. , Pham D. C. , Mendenhall N. P.
Published: March 2014

Our objective was to determine if protons allow for the expansion of treatment volumes to cover high-risk nodes in patients with regionally advanced non-small-cell lung cancer. In this study, 5 consecutive patients underwent external-beam radiotherapy treatment planning. Four treatment plans were generated for each patient: 1) photons (x-rays) to treat positron emission tomography (PET)-positive gross disease only to 74 Gy (XG); 2) photons (x-rays) to treat high-risk nodes to 44 Gy and PET-positive gross disease to 74 Gy (XNG); 3) protons to treat PET-positive gross disease only to 74 cobalt gray equivalent (PG); and 4) protons to treat high-risk nodes to 44 CGE and PET-positive gross disease to 74 CGE (PNG). We defined high-risk nodes as mediastinal, hilar, and supraclavicular lymph nodal stations anatomically adjacent to the foci of PET-positive gross disease. Four-dimensional computed tomography was utilized for all patients to account for tumor motion. Standard normal-tissue constraints were utilized. Our results showed that proton plans for all patients were isoeffective with the corresponding photon (x-ray) plans in that they achieved the desired target doses while respecting normal-tissue constraints. In spite of the larger volumes covered, median volume of normal lung receiving 10 CGE or greater (V10Gy/CGE), median V20Gy/CGE, and mean lung dose were lower in the proton plans (PNG) targeting gross disease and nodes when compared with the photon (x-ray) plans (XG) treating gross disease alone. In conclusion, proton plans demonstrated the potential to safely include high-risk nodes without increasing the volume of normal lung irradiated when compared to photon (x-ray) plans, which only targeted gross disease.
Assessment of Pulmonary Fibrosis after Radiotherapy (RT) in Breast Conserving Surgery: Comparison between Conventional External Beam RT (EBRT) and Intraoperative RT with Electrons (ELIOT)
Authors: Rampinelli C. , Bellomi M. , Ivaldi G. B. , Intra M. , Raimondi S. , Meroni S. , Orecchia R. , Veronesi U.
Published: March 2014

The aim of this study was to assess the frequency and the grade of RT-induced pulmonary fibrosis in patients who underwent EBRT compared to patients who underwent ELIOT. One-hundred-seventy-eight patients enrolled in a prospective randomized phase III trial to compare the efficacy of ELIOT (a single dose of 21 Gy prescribed at the 90% isodose) versus EBRT (50 Gy to the whole breast plus a 10 Gy boost to the tumour bed), underwent a spiral 16-detector row Computed Tomography (CT) examination to assess RT-induced pulmonary fibrosis: 83 patients in the EBRT arm and 95 in the ELIOT arm. All patients (age range 48–75 years) were affected by unicentric infiltrating carcinoma of the breast with diameter < 2.5 cm. This study was approved by our Institutional Ethical Committee and informed consent was obtained from each patient. Two observers, blinded to patient's randomization, independently evaluated each CT examination and assigned a fibrosis score (Grades 0 to 3). Inter-observer agreement for the fibrosis score was evaluated and a consensus between observers was obtained. Differences in fibrosis score between the two arms were evaluated by Chi Square test and Odds Ratio (OR) with 95% Confidence Intervals (CI). Pulmonary fibrosis was diagnosed in 42 patients (23.6%): 38 (90%) were in the EBRT arm and 4 (10%) in the ELIOT arm (p < 0.0001); twenty-six of them were Grade 1 (one ELIOT), fifteen were Grade 2 (three ELIOT) and one was Grade 3. The post-radiotherapy risk in the EBRT arm to develop at least Grade 1 fibrosis was 19 times higher than in the ELIOT one (OR: 19.20; 95%CI: 6.46–57.14) and 6 times higher to develop at least Grade 2 (OR: 5.70; 95%CI: 1.56–20.76). In conclusion, CT detected pulmonary fibrosis in patients treated with ELIOT is significantly less frequent compared to patients treated with EBRT.
Cryosurgery for Treatment of Subcutaneously Xenotransplanted Tumors in Rats and its Effect on Cellular Immunity
Authors: Liu J. G. , Chen F. L. , Ge C. L. , Gong M. Y. , Zuo H. B. , Zhang J. R.
Published: March 2014

Cryosurgery has shown encouraging therapeutic effects on some solid tumors but its effect on the cellular immunity remains unclear. We developed a subcutaneously xenotransplanted tumor model in SD rats to directly evaluate the immune response by detecting the serum cytokine levels, T-cell responses to tumor derived antigens, and the cytolytic activity of peripheral blood mononuclear cells against the W256 cancer line with apoptosis of cells being detected using TUNEL method. 66 SD rats were divided into 2 groups with group A having 36 rats and group B having 30 rats. 30 rats in group B were equally divided into 3 groups, tumor group B, cryosurgery group B and surgery group B, with 10 rats each. 36 rats in group A were equally divided into 2 groups, cryosurgery group A and tumor group A and treatment was done accordingly. The results showed that cryosurgery induced not only destruction of the tumor cells but also cell apoptosis around the cryosurgery foci. The apoptosis ratio reached the peak 12 h after cryosurgery, with an apoptosis rate of (68.28 ± 7.85)%. Compared with surgical resection that caused significant reduction in CD3+ and CD4+ cell percentages, cryosurgery resulted in significantly increased percentages of CD3+ and CD4+ cells (P < 0.05) with a relative increase of the CD4+/CD8+ cell ratio. However, sIL-2R level of peripheral blood of rats in cryosurgery group which decreased more rapidly than that in surgery group over time was significantly different 3 and 5 weeks after treatment compared to surgery group (P < 0.01). Moreover, cytotoxicity of mononuclear cell was significantly enhanced after cryosurgery, which is significantly higher in cryosurgery group (P = 0.05). These results demonstrate that in addition to tumor cell destruction, cryosurgery also results in enhanced cellular immunity and antitumor immune response of the rats with subcutaneously xenotransplanted tumor, suggesting the great potential of argon-helium cryosurgery in clinical management.
Constraining a compositional flow model with flow‐chemical data using an ensemble‐based Kalman filter
Authors: Gharamti M. E. , Kadoura A. , Valstar J. , Sun S. , Hoteit I.
Published: March 2014

Isothermal compositional flow models require coupling transient compressible flows and advective transport systems of various chemical species in subsurface porous media. Building such numerical models is quite challenging and may be subject to many sources of uncertainties because of possible incomplete representation of some geological parameters that characterize the system's processes. Advanced data assimilation methods, such as the ensemble Kalman filter (EnKF), can be used to calibrate these models by incorporating available data. In this work, we consider the problem of estimating reservoir permeability using information about phase pressure as well as the chemical properties of fluid components. We carry out state‐parameter estimation experiments using joint and dual updating schemes in the context of the EnKF with a two‐dimensional single‐phase compositional flow model (CFM). Quantitative and statistical analyses are performed to evaluate and compare the performance of the assimilation schemes. Our results indicate that including chemical composition data significantly enhances the accuracy of the permeability estimates. In addition, composition data provide more information to estimate system states and parameters than do standard pressure data. The dual state‐parameter estimation scheme provides about 10% more accurate permeability estimates on average than the joint scheme when implemented with the same ensemble members, at the cost of twice more forward model integrations. At similar computational cost, the dual approach becomes only beneficial after using large enough ensembles.
Magnetite Crystal Orientation in Magnetosome Chains
Authors: Körnig André , Winklhofer Michael , Baumgartner Jens , Gonzalez Teresa Perez , Fratzl Peter , Faivre Damien
Published: March 2014

One‐dimensional magnetic nanostructures have magnetic properties superior to non‐organized materials due to strong uniaxial shape anisotropy. Magnetosome chains in magnetotactic bacteria represent a biological paradigm of such magnet, where magnetite crystals synthesized in organelles called magnetosomes are arranged into linear chains. Two‐dimensional synchrotron X‐ray diffraction (XRD) is applied to cells of magnetotactic bacteria that are pre‐aligned with a magnetic field to determine the crystallographic orientation of magnetosomes relative to the chain axis. The obtained pole figure patterns reveal a [111] fiber texture along the chain direction for magnetospirilla strains MSR‐1 and AMB‐1, whereas a [100] fiber texture is measured for Desulfovibrio magneticus strain RS‐1. The [100] axis appears energetically unfavorable because it represents a magnetic hard axis in magnetite, but can be turned into an effective easy axis by particle elongation along [100] for aspect ratios higher than 1.25, consistent with aspect ratios in RS‐1 magnetosomes determined earlier. The pronounced fiber textures can be explained either by a strain‐specific biological control on crystal orientation at the chain level or by physical alignment effects due to intra‐chain magnetic interactions. In this case, biological control of the axis of elongation would be sufficient to influence the crystallographic texture of the magnetosome chain.
Gene‐targeted deletion of OPCML and Neurotrimin in mice does not yield congenital heart defects
Authors: Ye Maoqing , Parente Fabienne , Li Xiaodong , Perryman M. Benjamin , Zelante Leopoldo , Wynshaw‐Boris Anthony , Chen Ju , Grossfeld Paul
Published: March 2014

Jacobsen syndrome (11q‐) is a rare chromosomal disorder caused by deletions in distal11q. Many of the most common and severe congenital heart defects that occur in the general population occur in 11q‐. Previous studies have demonstrated that gene‐targeted deletion in mice of ETS‐1, a cardiac transcription factor in distal 11q, causes ventricular septal defects with 100% penetrance. It is unclear whether deletion of other genes in distal 11q contributes to the full spectrum of congenital heart defects that occur in 11q‐. Three patients with congenital heart defects have been identified that carry a translocation or paracentric inversion with a breakpoint in distal 11q disrupting one of two functionally related genes, OPCML and Neurotrimin. OPCML and Neurotrimin are two members of the IgLON subfamily of cell adhesion molecules. In this study, we report the generation and cardiac phenotype of single and double heterozygous gene‐targeted OPCML and Neurotrimin knockout mice. No cardiac phenotype was detected, consistent with a single gene model as the cause of the congenital heart defects in 11q‐. © 2014 Wiley Periodicals, Inc.
Causes of failure in endoscopic frontal sinus surgery in chronic rhinosinusitis patients
Authors: Valdes Constanza J. , Bogado Mariana , Samaha Mark
Published: March 2014

Background

The frontal sinus is the most challenging area to address in endoscopic sinus surgery (ESS). Incomplete surgery or iatrogenic injury in the narrow space of the frontal recess with synechia formation can lead to recurrence or persistence of disease. The goal of this study was to identify causes of failure of endoscopic frontal sinus surgery and to determine complication rates.

Methods

A cross‐sectional retrospective study was conducted. Charts and preoperative sinus computed tomography (CT) scans of patients who underwent revision frontal ESS for chronic frontal rhinosinusitis, between 2006 and 2012 were reviewed.

Results

Of 829 patients who underwent ESS during the study period, 740 had the frontal recess dissected and frontal sinus opened. Of these, 66 patients had revision surgery of the frontal sinus, with a total of 109 frontal sinuses. The mean ± standard deviation (SD) age was 52 ± 12.9 years. Forty patients were male (59.1%). The most common findings were the following: edematous or hypertrophic mucosa (92.7%); retained agger nasi cell (73.4%); neo‐osteogenesis within the frontal recess (45.9%); lateral scarring of the middle turbinate (47.7%); residual anterior ethmoid air cell (32.1.%); and residual frontal cells (24.8%).

Conclusion

With the exception of mucosal disease and neo‐osteogenesis, all identified causes of failure of frontal sinus surgery are a result of surgical technique. Careful preoperative planning and meticulous and complete surgical execution are therefore critical for a successful surgical outcome in primary frontal sinus surgery.
A comparative study on the free volume theories for diffusivity through polymeric membrane in pervaporation process
Authors: Mafi Amirhossein , Raisi Ahmadreza , Hatam Mohsen , Aroujalian Abdolreza
Published: March 2014

In this work, free volume theories are coupled with a thermodynamic model and generalized Fick's law to develop a mass transfer model based on solution‐diffusion mechanism for pervaporation process with a hydrophobic polymeric membrane. The Wesselingh, Fujita and Vrentas‐Duda's theories are used to calculate concentration‐dependent diffusion coefficient of permeants inside polydimethylsiloxane membrane. The sorption and pervaporation experiments on aqueous ethanol solutions are performed to validate the sorption and pervaporation models. The results reveal that the proposed models are able to predict influences of feed concentration and temperature as well as permeate‐side pressure on partial fluxes through the membrane. The comparative investigation indicated that Wesselingh's free volume theory underestimated the diffusion coefficients inside the membrane and the accuracy of the model used this theory is very low for prediction of the permeation flux. Generally, Fujita and Vrentas‐Duda's theories are found to be much more accurate especially for dilute aqueous feed solutions. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40581.
Castor oil and PEG‐based shape memory polyurethane films for biomedical applications
Authors: Bonfil Mirey , Sirkecioglu Ahmet , Bingol‐Ozakpinar Ozlem , Uras Fikriye , Güner F. Seniha
Published: March 2014

A series of polyurethane film were prepared from poly(ethylene glycol) with different molecular weight (PEG 1500, 3000, and 8000) and castor oil by one‐shot bulk polymerization method. Hexamethylene diisocyanate and 1,4‐buthane diol were used as diisocyanate and chain extender, respectively. In order to characterize the samples, their density, swelling ratio, water contact angle, surface free energy, gel content, thermal, and viscoelastic properties were determined. The effect of the soft segment length (SSL) and hard segment content (HSC) of all polyurethane films on their shape memory behavior such as shape fixity (Rf) and shape recovery (Rr) rates were investigated by bending test. Direct contact and MTT tests were used for assessment of cell adhesion and proliferation. The relatively high Rf and Rr values were obtained for the samples programmed at high temperature difference. Rf increased with decreasing HSC. On the other hand, Rr tended to decrease with increasing SSL. After evaluating experimental data by a nonlinear equation, it was found that HSC is more effective parameter on shape memory property than SSL. The gel content, swelling ratio, and water contact angle of the samples were dependent on both SSL and HSC in their structures. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40590.
Anatomy integration blueprint: A fourth‐year musculoskeletal anatomy elective model
Authors: Lazarus Michelle D. , Kauffman Gordon L. , Kothari Milind J. , Mosher Timothy J. , Silvis Matthew L. , Wawrzyniak John R. , Anderson Daniel T. , Black Kevin P.
Published: March 2014

Current undergraduate medical school curricular trends focus on both vertical integration of clinical knowledge into the traditionally basic science‐dedicated curricula and increasing basic science education in the clinical years. This latter type of integration is more difficult and less reported on than the former. Here, we present an outline of a course wherein the primary learning and teaching objective is to integrate basic science anatomy knowledge with clinical education. The course was developed through collaboration by a multi‐specialist course development team (composed of both basic scientists and physicians) and was founded in current adult learning theories. The course was designed to be widely applicable to multiple future specialties, using current published reports regarding the topics and clinical care areas relying heavily on anatomical knowledge regardless of specialist focus. To this end, the course focuses on the role of anatomy in the diagnosis and treatment of frequently encountered musculoskeletal conditions. Our iterative implementation and action research approach to this course development has yielded a curricular template for anatomy integration into clinical years. Key components for successful implementation of these types of courses, including content topic sequence, the faculty development team, learning approaches, and hidden curricula, were developed. We also report preliminary feedback from course stakeholders and lessons learned through the process. The purpose of this report is to enhance the current literature regarding basic science integration in the clinical years of medical school. Anat Sci Educ 7: 379–388. © 2014 American Association of Anatomists.
International coauthorship relations in the Social Sciences Citation Index: Is internationalization leading the Network?
Authors: Leydesdorff Loet , Park Han Woo , Wagner Caroline
Published: March 2014

International coauthorship relations have increasingly shaped another dynamic in the natural and life sciences during recent decades. However, much less is known about such internationalization in the social sciences. In this study, we analyze international and domestic coauthorship relations of all citable items in the DVD version of the Social Sciences Citation Index 2011 (SSCI). Network statistics indicate 4 groups of nations: (a) an Asian‐Pacific one to which all Anglo‐Saxon nations (including the United Kingdom and Ireland) are attributed, (b) a continental European one including also the Latin‐American countries, (c) the Scandinavian nations, and (d) a community of African nations. Within the EU‐28, 11 of the EU‐15 states have dominant positions. In many respects, the network parameters are not so different from the Science Citation Index. In addition to these descriptive statistics, we address the question of the relative weights of the international versus domestic networks. An information‐theoretical test is proposed at the level of organizational addresses within each nation; the results are mixed, but the international dimension is more important than the national one in the aggregated sets (as in the Science Citation Index). In some countries (e.g., France), however, the national distribution is leading more than the international one. Decomposition of the United States in terms of states shows a similarly mixed result; more U.S. states are domestically oriented in the SSCI and more internationally in the SCI. The international networks have grown during the last decades in addition to the national ones but not by replacing them.
Exploring Co‐training strategies for opinion detection
Authors: Yu Ning
Published: March 2014

For the last decade or so, sentiment analysis, which aims to automatically identify opinions, polarities, or emotions from user‐generated content (e.g., blogs, tweets), has attracted interest from both academic and industrial communities. Most sentiment analysis strategies fall into 2 categories: lexicon‐based and corpus‐based approaches. While the latter often requires sentiment‐labeled data to build a machine learning model, both approaches need sentiment‐labeled data for evaluation. Unfortunately, most data domains lack sufficient quantities of labeled data, especially at the subdocument level. Semisupervised learning (SSL), a machine learning technique that requires only a few labeled examples and can automatically label unlabeled data, is a promising strategy to deal with the issue of insufficient labeled data. Although previous studies have shown promising results of applying various SSL algorithms to solve a sentiment‐analysis problem, co‐training, an SSL algorithm, has not attracted much attention for sentiment analysis largely due to its restricted assumptions. Therefore, this study focuses on revisiting co‐training in depth and discusses several co‐training strategies for sentiment analysis following a loose assumption. Results suggest that co‐training can be more effective than can other currently adopted SSL methods for sentiment analysis.
Pulmonary hypertension in bronchopulmonary dysplasia
Authors: Ambalavanan Namasivayam , Mourani Peter
Published: March 2014

Pulmonary hypertension is common in bronchopulmonary dysplasia and is associated with increased mortality and morbidity. This pulmonary hypertension is due to abnormal microvascular development and pulmonary vascular remodeling resulting in reduced cross‐sectional area of pulmonary vasculature. The epidemiology, etiology, clinical features, diagnosis, suggested management, and outcomes of pulmonary hypertension in the setting of bronchopulmonary dysplasia are reviewed. In summary, pulmonary hypertension is noted in a fifth of extremely low birth weight infants, primarily those with moderate or severe bronchopulmonary dysplasia, and persists to discharge in many infants. Diagnosis is generally by echocardiography, and some infants require cardiac catheterization to identify associated anatomic cardiac lesions or systemic‐pulmonary collaterals, pulmonary venous obstruction or myocardial dysfunction. Serial echocardiography and B‐type natriuretic peptide measurement may be useful for following the course of pulmonary hypertension. Currently, there is not much evidence to indicate optimal management approaches, but many clinicians maintain oxygen saturation in the range of 91 to 95%, avoiding hypoxia and hyperoxia, and often provide inhaled nitric oxide, sometimes combined with sildenafil, prostacyclin, or its analogs, and occasionally endothelin‐receptor antagonists. Birth Defects Research (Part A) 100:240–246, 2014. © 2014 Wiley Periodicals, Inc.
The rise and fall of Picobiliphytes: How assumed autotrophs turned out to be heterotrophs
Authors: Moreira David , López‐García Purificación
Published: March 2014

Algae are significant members of Earth's biodiversity. Having been studied for a long time, the discovery of new algal phyla is extremely unusual. Recently, the enigmatic “Picobiliphyta,” a group of uncultured eukaryotes unveiled using molecular tools, were claimed to represent an unrecognized early branching algal lineage with a nucleomorph (remnant nucleus of a secondary algal endosymbiont) in their plastids. However, subsequent studies rejected the presence of a nucleomorph, and single‐cell genomic studies failed to detect any plastid‐related genes, ruling out the possibility of plastid occurrence. The isolation of the first “picobiliphyte,” Picomonas judraskeda, a tiny organism that feeds on very small (<150 nm) organic particles, came as final proof of their non‐photosynthetic lifestyle. Consequently, the group has been renamed Picozoa. The passage from “picobiliphytes” to “picozoa” illustrates the crucial role that classical protistology should play to provide sound biological context for the wealth of data produced by modern molecular techniques.
Getting tubulin to the tip of the cilium: One IFT train, many different tubulin cargo‐binding sites?
Authors: Bhogaraju Sagar , Weber Kristina , Engel Benjamin D. , Lechtreck Karl‐Ferdinand , Lorentzen Esben
Published: March 2014

Cilia are microtubule‐based hair‐like structures that project from the surfaces of eukaryotic cells. Cilium formation relies on intraflagellar transport (IFT) to move ciliary proteins such as tubulin from the site of synthesis in the cell body to the site of function in the cilium. A large protein complex (the IFT complex) is believed to mediate interactions between cargoes and the molecular motors that walk along axonemal microtubules between the ciliary base and tip. A recent study using purified IFT complexes has identified a tubulin‐binding module in the two core IFT proteins IFT74 and IFT81 that likely serves to bind and transport tubulin within cilia. Here, we calculate the amount of tubulin required to support the observed cilium assembly kinetics and explore the possibility of multiple tubulin binding sites within the IFT complex.
Structured additive regression modeling of age of menarche and menopause in a breast cancer screening program
Authors: Duarte Elisa , de Sousa Bruno , Cadarso‐Suarez Carmen , Rodrigues Vitor , Kneib Thomas
Published: March 2014

Breast cancer risk is believed to be associated with several reproductive factors, such as early menarche and late menopause. This study is based on the registries of the first time a woman enters the screening program, and presents a spatio‐temporal analysis of the variables age of menarche and age of menopause along with other reproductive and socioeconomic factors. The database was provided by the Portuguese Cancer League (LPCC), a private nonprofit organization dealing with multiple issues related to oncology of which the Breast Cancer Screening Program is one of its main activities. The registry consists of 259,652 records of women who entered the screening program for the first time between 1990 and 2007 (45–69‐year age group). Structured Additive Regression (STAR) models were used to explore spatial and temporal correlations with a wide range of covariates. These models are flexible enough to deal with a variety of complex datasets, allowing us to reveal possible relationships among the variables considered in this study. The analysis shows that early menarche occurs in younger women and in municipalities located in the interior of central Portugal. Women living in inland municipalities register later ages for menopause, and those born in central Portugal after 1933 show a decreasing trend in the age of menopause. Younger ages of menarche and late menopause are observed in municipalities with a higher purchasing power index. The analysis performed in this study portrays the time evolution of the age of menarche and age of menopause and their spatial characterization, adding to the identification of factors that could be of the utmost importance in future breast cancer incidence research.
Survival Analysis in Medicine and Genetics by LI, JIALIANG and MA, SHUANGGE
Authors: Lee Seungyeoun
Published: March 2014

EDITOR: TAESUNG PARK

Survival Analysis in Medicine and Genetics

(Jialiang Li and Shuangge Ma)

Seungyeoun Lee

Bayesian Methods in Health Economics

(Gianluca Baio)

Man‐Suk Oh

Methods of Statistical Model Estimation

(Joseph M. Hilbe and Andrew P. Robinson)

Jae‐kwang Kim
Evaluating two process scale chromatography column header designs using CFD
Authors: Johnson Chris , Natarajan Venkatesh , Antoniou Chris
Published: March 2014

Chromatography is an indispensable unit operation in the downstream processing of biomolecules. Scaling of chromatographic operations typically involves a significant increase in the column diameter. At this scale, the flow distribution within a packed bed could be severely affected by the distributor design in process scale columns. Different vendors offer process scale columns with varying design features. The effect of these design features on the flow distribution in packed beds and the resultant effect on column efficiency and cleanability needs to be properly understood in order to prevent unpleasant surprises on scale‐up. Computational Fluid Dynamics (CFD) provides a cost‐effective means to explore the effect of various distributor designs on process scale performance. In this work, we present a CFD tool that was developed and validated against experimental dye traces and tracer injections. Subsequently, the tool was employed to compare and contrast two commercially available header designs. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 30:837–844, 2014
Serum‐free spheroid suspension culture maintains mesenchymal stem cell proliferation and differentiation potential
Authors: Alimperti Stella , Lei Pedro , Wen Yuan , Tian Jun , Campbell Andrew M. , Andreadis Stelios T.
Published: March 2014

There have been many clinical trials recently using ex vivo‐expanded human mesenchymal stem cells (MSCs) to treat several disease states such as graft‐versus‐host disease, acute myocardial infarction, Crohn's disease, and multiple sclerosis. The use of MSCs for therapy is expected to become more prevalent as clinical progress is demonstrated. However, the conventional 2‐dimensional (2D) culture of MSCs is laborious and limited in scale potential. The large dosage requirement for many of the MSC‐based indications further exacerbates this manufacturing challenge. In contrast, expanding MSCs as spheroids does not require a cell attachment surface and is amenable to large‐scale suspension cell culture techniques, such as stirred‐tank bioreactors. In the present study, we developed and optimized serum‐free media for culturing MSC spheroids. We used Design of Experiment (DoE)‐based strategies to systematically evaluate media mixtures and a panel of different components for effects on cell proliferation. The optimization yielded two prototype serum‐free media that enabled MSCs to form aggregates and proliferate in both static and dynamic cultures. MSCs from spheroid cultures exhibited the expected immunophenotype (CD73, CD90, and CD105) and demonstrated similar or enhanced differentiation potential toward all three lineages (osteogenic, chondrogenic, adipogenic) as compared with serum‐containing adherent MSC cultures. Our results suggest that serum‐free media for MSC spheroids may pave the way for scale‐up production of MSCs in clinically relevant manufacturing platforms such as stirred tank bioreactors. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 30:974–983, 2014
Information policy and mobile privacy
Authors: Begany Grace
Published: March 2014

EDITOR'S SUMMARY

With mobile devices now Americans' primary source of Internet access, privacy issues have prompted the Federal Trade Commission (FTC) to issue voluntary best practices for the industry to respect consumer privacy and avoid enforcement scrutiny. The FTC calls on mobile platform operating system providers, mobile app developers, advertising networks and analytics firms and others to build in privacy disclosures, alerts and management tools. California has issued mobile privacy recommendations, and the U.S. Department of Commerce National Telecommunication and Information Administration is developing a consumer data privacy code of conduct. Recent cases illustrate the need for governmental oversight, and industry stakeholders and consumer groups agree in principle, but the degree and details are debatable. Regulators should not delay laying groundwork for firm mobile privacy legislation.
Odds of death after glioblastoma diagnosis in the United States by chemotherapeutic era
Authors: Wachtel Mitchell S. , Yang Shengping
Published: March 2014

Bevacizumab (BZM) and temozolomide (TMZ) have been shown to be beneficial in the treatment of patients with glioblastoma. We sought evidence for the benefit of BZM in the general patient population at large. The Surveillance, Epidemiology, and End Results SEER database was queried for patients diagnosed with glioblastoma between 2000 and 2009, divided into a pre‐TMZ era (January 2000–June 2003), a transitional era (July 2003–March 2005), a TMZ era (April 2005–October 2007), and a BZM‐TMZ era (November 2007–December 2009). Binomial logit regression analyzed odds of death, taking into account age at diagnosis, tumor size, gender, race, marital status, radiotherapy, and extensive surgery. Compared with the pre‐TMZ era, odds of death were decreased in the TMZ era by 12% (97.5% CI [confidence interval] 3–20%) 6 months after diagnosis and 36% (30–42%) a year after diagnosis; corresponding values for BZM‐TMZ were 31% (24–37%) and 50% (45–55%). For era comparisons, decreases in odds of death were larger at 12 than 6 months; the opposite was true for extensive surgery and radiotherapy (P < 0.025, Wald χ2 test, for each analysis). For both 6 and 12 month comparisons, odds of death in the BZM‐TMZ era were lower than in the TMZ era (P < 0.025, Wald χ2 test, for each analysis). The results provide evidence that TMZ positively impacted survival of glioblastoma patients and that the addition of BZM further improved survival, this lends support to the addition of BZM to the chemotherapeutic armamentarium. Evaluation of odds of death is an attractive alternative to Cox regression when proportional hazards assumptions are violated and follow‐up is good.
Mass Transfer in Molybdenum Extraction from Aqueous Solutions Using Nanoporous Membranes
Authors: Ghadiri Mehdi , Ashrafizadeh Seyed N.
Published: March 2014

Modeling of non‐disperse solvent extraction of molybdenum(VI) with PC‐88A as extractant and a nanoporous hollow‐fiber membrane contactor as extractor was performed. Computational fluid dynamics was applied for modeling and simulation of molybdenum extraction. Concentration, pressure, and velocity distributions for molybdenum were determined. The extraction of Mo6+ was greatly influenced by the flow rate of feed solution. The extraction efficiency was reduced with higher feed flow rate and increased with the molybdenum content in the feed. The pressure drop along the shell side of the membrane extractor was found to be not significant, being one of the advantages of membrane extractors which assist in reducing the operational costs. The proposed simulation method is capable to prognosticate the performance of solvent extraction of molybdenum in membrane extractors.
The Degradation of Natural Organic Matter in Surface Water by a Nano‐TiO2/Diatomite Photocatalytic Reactor
Authors: Sun Wen , Chu Huaqiang , Dong Bingzhi , Cao Dawen , Zheng Shuilin
Published: March 2014

A new nano‐TiO2/diatomite (NTD) composite was employed in a photocatalytic reactor to assess the removal of natural organic matter (NOM) at fluxes ranging from 0.6 to 1.8 L/h. Various analytical methods, such as scanning electron microscopy, Fourier transform infrared spectrometry, X‐ray diffraction, and high performance size exclusion chromatography–UV/Vis detector‐total organic carbon (TOC), were adopted. The experimental results found that the NTD photocatalytic reactor was effective in removing NOM from raw water. The flux had a significant effect on the degradation of TOC, and the UV absorbance at 254 nm (UV254) increased as the decreasing flux and the prolonged photocatalytic operation. According to the analysis of the NOM fractionation results, the absorption and photocatalysis by the NTD particles removed different NOM fractions, and the very hydrophobic acids and neutral hydrophilic acids of lager molecular weight could be strongly degraded by the NTD photocatalytic reactor.
Cometabolic Degradation Kinetics of Trichloroethylene Based on Toluene Enhancement by Encapsulated Burkholderia cepacia G4
Authors: Hamid Shanawar , Amin Muhammad T. , Alazba Abdulrahman A. , Manzoor Umair , Amin Muhammad N.
Published: March 2014

The ability of encapsulated Burkholderia cepacia G4 (ATCC 53617) for trichloroethylene (TCE) degradation (1.5, 5, 10, and 20 mg/L) in the presence of toluene (10 and 60 mg/L) as enhancement substrate was evaluated experimentally. Burkholderia cepacia G4 cultures were encapsulated in cylindrical pellets (4 mm in diameter and 4 mm in height (preferred)) using polyethylene glycol (PEG). Higher transformation capacities were observed for the encapsulated cultures for both toluene concentrations. The highest transformation capacities measured for the encapsulated cultures and suspended cultures were 46.98 and 5.94 μg TCE/mg biomass, respectively. The Monod equation was used to simulate the degradation rates of toluene and Haldane's equation was employed to describe the degradation kinetics of TCE. The first‐order reaction rate constant (k/Ks) for toluene degradation in the encapsulated cultures was 2.3‐fold higher than the value of the suspended cultures, whereas the kc/Ksc value for TCE was 4.3‐fold higher compared to the suspended cultures. The higher kinetic values of the encapsulated cultures indicate that the degradation efficiency and capability of B. cepacia G4 was enhanced through PEG encapsulation. Moreover, the higher inhibition constant value for the encapsulated cultures compared with the suspended cultures demonstrated that PEG‐encapsulated B. cepacia G4 can tolerate and degrade much higher TCE concentrations.
Phase 2 trial of erlotinib combined with cisplatin and radiotherapy in patients with locally advanced cervical cancer
Authors: Nogueira‐Rodrigues Angelica , Moralez Giulliana , Grazziotin Rachele , Carmo Claudio C. , Small Isabele A. , Alves Flavia V.G. , Mamede Marcelo , Erlich Felipe , Viegas Celia , Triginelli Sergio A. , Ferreira Carlos G.
Published: March 2014

BACKGROUND

Cisplatin‐based chemoradiation (CRT) is the standard treatment for patients with locally advanced cervical cancer. Epidermal growth factor receptor (EGFR) is frequently overexpressed in cervical cancer, and EGFR inhibition itself has antitumor effects and potentiates CRT. Results of a previous phase 1 trial of the EGFR inhibitor erlotinib combined with cisplatin‐based CRT (E + CRT) recommended a phase 2 erlotinib dose of 150 mg/day.

METHODS

Eligibility criteria included International Federation of Gynecology and Obstetrics stage IIB to IIIB epidermoid cervical cancer, no prior therapy, and an Eastern Cooperative Oncology Group performance status of 0 to 2. Patients received erlotinib at a dose of 150 mg/day 1 week before and in combination with cisplatin (40 mg/m2 administered weekly for 5 cycles) and radiotherapy (4500 centigrays in 25 fractions), followed by brachytherapy (4 fractions at a dose of 600 centigrays weekly).

RESULTS

A total of 36 patients completed treatment with E + CRT. The median duration of therapy was 77 days and the median follow‐up period was 59.3 months. The therapy was well tolerated overall, and 34 patients (94.4%) achieved a complete response. The 2‐year and 3‐year cumulative overall and progression‐free survival rates were 91.7% and 80.6% and 80% and 73.8%, respectively.

CONCLUSIONS

Treatment with E + CRT appears to be safe and exerts significant activity against locally advanced cervical cancer. To the best of the authors' knowledge, this is the first study to date to demonstrate that a target agent has promising activity against locally advanced cervical cancer. Cancer 2014;120:1187–1193. © 2014 American Cancer Society.
Resistive‐less memcapacitor‐based relaxation oscillator
Authors: Fouda Mohamed E. , Radwan Ahmed G.
Published: March 2014

Recently, the realization of the conventional relaxation oscillators was introduced based on memristors. This paper validates the concept using two series memcapacitors in general which is applicable for a capacitor and memcapacitor as well. Furthermore, the necessary conditions for oscillation are introduced, and a generalized closed‐form expression for the oscillation frequency is derived. Two special cases are introduced and verified using PSPICE simulations showing a perfect matching. Copyright © 2014 John Wiley & Sons, Ltd.
Secular trends in eating problems among norwegian adolescents from 1992 to 2010
Authors: von Soest Tilmann , Wichstrøm Lars
Published: March 2014

Objective

This study examines secular trends in eating problems among adolescents between 1992 and 2010. The study aims further to investigate whether such trends can be accounted for by secular changes in putative risk factors.

Method

Three nationwide surveys of Norwegian senior high‐school students were conducted in 1992, 2002, and 2010 (response rates 97.0, 91.0, and 83.2%). At each time point, approximately 3,000 adolescents participated. Eating problems were assessed by means of the Dieting and the Bulimia and Food Preoccupation subscales of the Eating Attitude Test‐12. Moreover, a variety of potential risk factors that might account for time trends in such problems were measured.

Results

Dieting scores increased almost linearly for both genders during the research period. No differences over time in Bulimia and Food Preoccupation scores were seen among boys, whereas these symptoms peaked in 2002 for girls with considerably lower levels in both 1992 and 2010. The increase in Dieting from 1992 to 2010 for both genders could be attributed in part to increasing body mass index levels and, to a lesser degree, to depressive symptoms among females. The girls' time trend in Bulimia and Food Preoccupation was to some extent related to changes in appearance satisfaction, alcohol intoxication, and global self‐worth.

Discussion

This study is one of few to statistically examine how secular trends in eating problems are related to changes in putative risk factors. The study does not however provide conclusive information on the causal direction between putative risk factors and eating problems. © 2014 Wiley Periodicals, Inc. (Int J Eat Disord 2014; 47:448–457)
Stressful environments can indirectly select for increased longevity
Authors: Savory Fiona R. , Benton Timothy G. , Varma Varun , Hope Ian A. , Sait Steven M.
Published: March 2014

Longevity is modulated by a range of conserved genes in eukaryotes, but it is unclear how variation in these genes contributes to the evolution of longevity in nature. Mutations that increase life span in model organisms typically induce trade‐offs which lead to a net reduction in fitness, suggesting that such mutations are unlikely to become established in natural populations. However, the fitness consequences of manipulating longevity have rarely been assessed in heterogeneous environments, in which stressful conditions are encountered. Using laboratory selection experiments, we demonstrate that long‐lived, stress‐resistant Caenorhabditis elegans age‐1(hx546) mutants have higher fitness than the wild‐type genotype if mixed genotype populations are periodically exposed to high temperatures when food is not limited. We further establish, using stochastic population projection models, that the age‐1(hx546) mutant allele can confer a selective advantage if temperature stress is encountered when food availability also varies over time. Our results indicate that heterogeneity in environmental stress may lead to altered allele frequencies over ecological timescales and indirectly drive the evolution of longevity. This has important implications for understanding the evolution of life‐history strategies.