bluuebunny/crossref_metadata_2025 huggingface dataset:
Wind Force on Tall Structure: An Approach From SPH
Authors: Ahmed Ananna , Baki Abdullah Hil , Noor Munaz Ahmed
Published: October 2012

Wind pressure calculation for tall building frame has always been an extensive job. Usual methods used to estimate wind load are Wind tunnel test method and Finite Element Method and specifications has been derived. In this research, with a view to eliminating drawbacks of these methods and providing a visual interpretation of wind flow a third method is introduced using Smooth Particle Hydrodynamics (SPH) Approach. A model simulation was performed by a SPH software named SPHysics to calculate the pressure exerted on the structure and to derive a graphical interpretation of flow pattern using Para View. Values of pressure at different elevation of the building that actually occurs when wind with certain velocity flows through a tall building are found. From the data found, height vs. pressure graphs are generated which clearly supports the proportional relationship between these two parameters even with triangular and parabolic variation. Again, velocity vs. pressure graphs are plotted which also justifies inter-relationship of proportionality. This is a qualitative comparison not a quantitative one as there is many limitations regarding technicality, computer capacity, and time. These values may be crosschecked with the values found from conventional methods when more precise and suitable boundary conditions can be used in simulation. In future, with intricate detailing and suitable three dimensional modeling, more accurate value of pressure can be found with wide range of applicability. The authors are expecting derivation of two equations as a function of height and velocity to calculate wind load to use in design if further proceeding is possible. This can offer a significant benefit of simplicity for users and can be beginning a new era of using SPH in structural engineering.   Keywords - Wind force, tall structure, Particle Hydrodynamics Approach
Raman Spectroscopy of Oral Buccal Mucosa: A Study on Age-Related Physiological Changes and Tobacco-Related Pathological Changes
Authors: Sahu Aditi , Deshmukh Atul , Ghanate A. D. , Singh S. P. , Chaturvedi Pankaj , Krishna C. Murali
Published: October 2012

Biophysical techniques play an important role in detecting physiological alterations during pathogenesis. Raman spectroscopy has shown immense potential in identifying several diseased conditions, including oral cancers. Classification of normal, inflammatory, premalignant and malignant conditions has been demonstrated using ex vivo Raman spectroscopy. Feasibility of recording in vivo spectra in clinically implementable time has also been shown. Translation of this technology to clinics requires extensive validation of methodologies, building of robust models and testing the same under stringent conditions as well as on diverse populations. In this context, the ability of Raman spectroscopy in identifying subtle changes in oral mucosa with increasing age, and the influence of these aging related changes on classification with tobacco-related pathological changes was evaluated. A total of 451 spectra from 62 subjects were recorded from buccal mucosa of healthy subjects of 4 different age groups (aged 20–60 years). Also, 478 spectra from 85 subjects belonging to 4 different categories, tobacco exposed mucosa, contralateral normal (opposite side of tumor), premalignant patches and tumors on buccal mucosa were recorded using fiber optic probe-coupled commercial Raman spectrometer. Differences in spectra were explored by unsupervised Principal Component Analysis (PCA) and supervised Linear Discriminant Analysis (LDA), followed by Leave one out cross validation. Results indicate feasibility of classifying early and late age groups. Also, clear classification is observed between healthy and pathological groups, thus inherent heterogeneity in healthy groups seems to have no bearing on classification of normal with abnormal conditions. Findings of the study indicate high sensitivity of Raman spectroscopy in detecting subtle mucosal changes, further supporting efficacy of Raman spectroscopic approaches in oral cancer applications. Prospectively, more vigorous validation studies of Raman methodology would enable routine clinical applications.
Toxicity and Outcome of Intensity-Modulated Radiotherapy versus 3-Dimensional Conformal Radiotherapy for Oropharyngeal Cancer: A Matched-Pair Analysis
Authors: Al-Mamgani Abrahim , Van Rooij Peter , Tans Lisa , Teguh David N. , Levendag Peter C.
Published: October 2012

Because of the scarcity of randomized trials comparing toxicity and outcomes of intensity-modulated radiotherapy (IMRT) for oropharyngeal cancer (OPC) with 3D-conformal radiotherapy (3DCRT), we performed a matched-pair analysis from prospectively collected data from the Head and Neck Tumor Registry of our institution. In the absence of phase III trials, we believe this approach provides the highest quality data possible. Ninety-two patients treated with 3DCRT were matched (1:1) to 92 patients treated with IMRT for 9 potential predictive factors for toxicity and outcome: gender, age, T-stage, N-stage, tumor subsite, unilateral neck irradiation, chemotherapy, neck dissection and boost technique. Groups were compared for acute and late toxicity, locoregional control (LRC), disease-free survival (DFS), and overall survival (OS). Oncologic outcomes were estimated using Kaplan-Meier analyses and toxicity was analyzed according to Common Terminology Criteria for Adverse Events v3.0. The overall incidence of grade 3 acute toxicity was significantly reduced by IMRT, compared to 3DCRT (45% vs. 70%, p = 0.001). The need for tube feeding was reduced from 50% to 37% ( p = 0.04). The 3-year actuarial incidence of grade ≥2 late toxicity was also significantly reduced by IMRT, compared to 3DCRT (20% vs. 45%, respectively; p < 0.0001). The incidence of grade ≥2 late dysphagia and xerostomia for IMRT vs. 3DCRT were 10% vs. 31% for dysphagia, p = 0.004 and 13% vs. 37%, for xerostomia, respectively ( p = 0.001). The 3-year Kaplan-Meier estimates of LRC, DFS, and OS for IMRT vs. 3DCRT were 90% vs. 82% ( p = 0.1), 82% vs. 76% ( p = 0.3), and 72% vs. 64% ( p = 0.2), respectively. In conclusion, the presented nonrandomized comparative study of well-matched groups demonstrates the superiority of IMRT vs. 3DCRT for OPC by significantly reducing radiation-induced toxicity without jeopardizing outcomes. The improved therapeutic ratio achieved by the use of IMRT would allow dose escalation of radiotherapy to further improve outcomes of patients with OPC.
Rodent Models of Colorectal Distension
Authors: O'Mahony Siobhain M. , Tramullas Monica , Fitzgerald Patrick , Cryan John F.
Published: October 2012

Colorectal distension (CRD) is a widely accepted, reproducible method for assessing visceral sensitivity in both clinical and pre‐clinical studies. Distension of the colon mirrors the human scenario of visceral pain with regard to intensity and referral of pain in patients. There are several readouts that can be applied to the CRD protocol depending on the species being evaluated, two of which are described in this unit. CRD can be used to measure the impact of novel compounds, strain, or genetic differences as well as the effect of physical and psychological stressors on the sensitivity of the colon. Investigation of the impact of a noxious visceral stimulus (CRD) on other systems within the body can also be carried out. Given that visceral pain is a major clinical problem and one of the most common reasons patients seek out medical advice, the ability to assess this type of pain is essential to the discovery of successful treatments. This unit outlines two protocols that describe CRD of rats and mice. Curr. Protoc. Neurosci. 61:9.40.1‐9.40.13. © 2012 by John Wiley & Sons, Inc.
Deviancy and Normative Training Processes in Experimental Groups of Delinquent and Nondelinquent Male Adolescents
Authors: Mathys Cécile , Hyde Luke W. , Shaw Daniel S. , Born Michel
Published: October 2012

The goal of this study was to identify the predictors and the moderators of group characteristics that influence deviancy and normative training processes in delinquent male adolescents. The authors experimentally tested the effects of group composition on deviant talk interaction processes among groups in which all members presented delinquent behaviors (“pure” delinquent group condition), those that included adolescents with no delinquent behaviors (“pure” normative group condition), and adolescents with both profiles (“mixed” group condition). Participants were 70 male adolescents aged 15–18 (M = 16.5; 56% Caucasian), with a random assignment to groups. Data were collected among three group sessions (T1, T2, T3), one session a week, using videotape. Two contents of interactions were also measured: antisocial and normative stories, counterbalanced across sessions. Results showed a significant group effect for antisocial talk and its reinforcement, with less antisocial talk within the mixed group condition in comparison to the pure delinquent group condition. The topic of interaction was also observed as a predictor of antisocial talk, with less normative interactions and more antisocial talk associated with antisocial topics. Finally, time moderated some relations between experimental groups and talk. We conclude with a discussion of the implications of this work for future research on deviancy training processes. Aggr. Behav. 39:30‐44, 2013. © 2012 Wiley Periodicals, Inc.
Direct Threat of a UV‐Ozone Treated Indium‐Tin‐Oxide Substrate to the Stabilities of Common Organic Semiconductors
Authors: Lo Ming‐Fai , Ng Tsz‐Wai , Mo Hin‐Wai , Lee Chun‐Sing
Published: October 2012

Ultraviolet‐ozone treated indium‐tin‐oxide (UV‐ITO) glass substrates have been widely and unquestioningly used in the field of organic electronics to improve both device performance and stability. Evidence is presented here for rapid decay of common organic films such as N,N′‐bis(naphthalen‐1‐ yl)‐N,N′‐bis(phenyl)‐benzidine (NPB), tris(8‐hydroxy‐quinolinato)aluminum (Alq3), and rubrene when they are in contact with an UV‐ITO substrate. While the photoluminescence (PL) of these organic films deposited on an UV‐ITO substrate decay rapidly under illumination; those on quartz substrates are comparatively much more stable. Results from X‐ray and UV photoemission spectroscopies (XPS and UPS) further suggest that degradations of the rubrene films on UV‐ITO substrate are mainly attributed to active oxygen species generated upon UV‐ozone treatment. These reactive oxygen species on the UV‐ITO surface behave as a reservoir of oxygen that interacts with rubrene and shifts its highest occupied molecular orbital (HOMO) level away from the Fermi level. This interaction induces a gap‐state in the energy gap of rubrene, which acts as a charge recombination center. More importantly, enhanced stabilities of rubrene‐based organic photovoltaic (OPV) devices are demonstrated when they are fabricated on gold‐coated or trifluoromethane (CHF3) plasma‐treated ITO. The presented works shows that the commonly used UV‐ITO substrate is a threat to the stability of addlayer organic semiconducting films.
Analysis of level A in vitro–in vivo correlations for an extended‐release formulation with limited bioavailability
Authors: Kakhi Maziar , Marroum Patrick , Chittenden Jason
Published: October 2012

A two‐stage, numerical deconvolution approach was employed to develop level A in vitro–in vivo correlations using data for three formulations of an extended‐release oral dosage form. The in vitro dissolution data for all formulations exhibited near‐complete dissolution within the time frame of the test. The pharmacokinetic concentration–time profiles for 16 subjects in a cross‐over study demonstrated notably limited bioavailability for the slowest formulation. These data were used as the basis for the IVIVC model development. Two models were identified that satisfied the nominal requirements for a conclusive internal predictability of the IVIVC, provided that all three formulations were used as internal datasets. These were a simple linear model with absorption cut‐off and a piecewise‐linear variable absorption scale model. A subsequent cross‐validation of the models' robustness indicated that neither model predicted satisfactorily the pharmacokinetic characteristics of all formulations in a conclusive manner. The piecewise‐linear variable absorption scale model provided the most accurate results, particularly with respect to the prediction of the slowest formulation's pharmacokinetic metrics. But this latter model also involved additional free parameters compared with the simple linear model with absorption cut‐off. It is argued that more complex IVIVC models with extra parameterization require comprehensive validation to ascertain the accuracy and robustness of the model. In order to achieve this, it is necessary to ensure a complete suite of supporting datasets for internal and external validation, irrespective of the mathematical approach used subsequently to develop the IVIVC. Copyright © 2013 John Wiley & Sons, Ltd.
DNA‐based chemiluminescent nanoprobes for highly sensitive and selective detection of mercury(II) ion
Authors: Yu Xijuan , Liu Xiangnan , Mou Chuanqin , Wang Zhiguang
Published: October 2012

A simple and sensitive DNA‐stablized gold nanoparticle (AuNP)‐based chemiluminescent (CL) probe for detecting mercury ion (Hg2+) in aqueous solution has been developed. The CL strategy relies upon the catalytic activity of unmodified AuNPs on the luminol–H2O2 CL reaction, and the interaction of unmodified AuNPs with DNA. The unmodified AuNPs can effectively differentiate unstructured and folded DNA. The DNA desorbs from AuNPs in the presence of Hg2+, leading to the increase in CL signal. By rationally varying the number of thymine in single‐strand oligonucleotides, the detection range could be tuned. Employing single‐strand oligonucleotides with 14 thymine in the detecting system, a sensitive linear range for Hg2+ ions from 5.0 × 10–10 to 1.0 × 10–7 mol/L and a detection limit of 2.1 × 10–10 mol/L are obtained. Changing the number of thymine to 10 and 6, it leads to a narrow detection range but a high sensitivity. Besides, DNA‐based CL nanoprobes exhibit a remarkable selectivity for Hg2+ ions over a variety of competing metal ions. Copyright © 2012 John Wiley & Sons, Ltd.
Quantitative proteomic profiling reveals photosynthesis responsible for inoculum size dependent variation in Chlorella sorokiniana
Authors: Ma Qian , Wang Jiangxin , Lu Shuhuan , Lv Yajin , Yuan Yingjin
Published: October 2012

High density cultivation is essential to industrial production of biodiesel from microalgae, which involves in variations of micro‐environment around individual cells, including light intensity, nutrition distribution, other abiotic stress and so on. To figure out the main limit factor in high inoculum cultivation, a quantitative proteomic analysis (iTRAQ‐on‐line 2‐D nano‐LC/MS) in a non‐model green microalga, Chlorella sorokiniana, under different inoculum sizes was conducted. The resulting high‐quality proteomic dataset consisted of 695 proteins. Using a cutoff of P < 0.05, 241 unique proteins with differential expression levels were identified between control and different inoculum sizes. Functional analysis showed that proteins participating in photosynthesis (light reaction) and Calvin cycle (carbon reaction pathway) had highest expression levels under inoculum size of 1 × 106 cells mL−1, and lowest levels under 1 × 107 cells mL−1. Canonical correlation analysis of the photosynthesis related proteins and metabolites biomarkers showed that a good correlation existed between them (canonical coefficient was 0.987), suggesting photosynthesis process greatly affected microalgae biodiesel productivity and quality. Proteomic study of C. sorokiniana under different illuminations was also conducted to confirm light intensity as a potential limit factor of high inoculum size. Nearly two thirds of proteins showed up‐regulation under the illumination of 70–110 µmol m−2 s−1, compared to those of 40 µmol m−2 s−1. This result suggested that by elegantly adjusting light conditions, high cell density cultivation and high biodiesel production might be achieved. Biotechnol. Bioeng. 2013; 110: 773–784. © 2012 Wiley Periodicals, Inc.
Development of Zn–ProPhenol‐Catalyzed Asymmetric Alkyne Addition: Synthesis of Chiral Propargylic Alcohols
Authors: Trost Barry M. , Bartlett Mark J. , Weiss Andrew H. , von Wangelin Axel Jacobi , Chan Vincent S.
Published: October 2012

The development of a general and practical zinc‐catalyzed enantioselective alkyne addition methodology is reported. The commercially available ProPhenol ligand (1) has facilitated the addition of a wide range of zinc alkynylides to aryl, aliphatic, and α,β‐unsaturated aldehydes in high yield and enantioselectivity. New insights into the mechanism of this reaction have resulted in a significant reduction in reagent stoichiometry, enabling the use of precious alkynes and avoiding the use of excess dimethylzinc. The enantioenriched propargylic alcohols from this reaction serve as versatile synthetic intermediates and have enabled efficient syntheses of several complex natural products.
Structural, Electronic and Optical Properties of Multifunctional Iridium(III) and Platinum(II) Metallophosphors for Organic Light‐Emitting Diodes
Authors: Ran Xueqin , Feng Jikang , Wong Waiyeung , Ren Aimin , Zhou Guijiang , Sun Chiachung
Published: October 2012

An elaborated theoretical investigation on the optical and electronic properties of three fluorene‐based platinum(II) and iridium(III) cyclometalated complexes Pt‐a, Ir‐a and Ir‐b is reported. The geometric and electronic structures of the complexes in the ground state are studied with density functional theory and Hartree Fock approaches, while the lowest triplet excited states are optimized by singles configuration interaction (CIS) methods. At the time‐dependent density functional theory (TD‐DFT) level, molecular absorption and emission properties were calculated on the basis of optimized ground‐ and excited‐state geometries, respectively. The computational results show that the appearance of triphenylamino (TPA) moiety at the 9‐position of fluorene ring favors the hole‐creation and leads to red‐shifts of absorption and emission spectra. Moreover, Pt‐a and Ir‐b are nice hole‐transporting materials whereas Ir‐a has good charge‐transfer balance, which render them useful for the realization of efficient OLEDs (Organic Light‐Emitting Diodes).
Synthesis and Properties of Degradable Copolymers Composed of Poly(ε‐caprolactone) and 3,4‐Dihydroxycinnamic Acid
Authors: Li Jihang , Shi Dongjian , Xu Huaqing , Hu Na , Dong Weifu , Chen Mingqing
Published: October 2012

Photoreactive and degradable hyperbranched (HB) copolymers with various 3,4‐dihydroxycinnamic acid (DHCA) compositions, poly(ε‐caprolactone)‐co‐poly(3,4‐dihydroxycinnamic acid) (PCL‐co‐PDHCA), were obtained by thermal melt‐polycondensation of PCL and DHCA. The HB structures and the branching degree (BD) of the PCL‐co‐PDHCA copolymers were confirmed by Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (1H NMR). The melting points (Tm) of the PCL‐co‐PDHCA copolymers changed depending on the PCL and DHCA composition by differential scanning calorimetry (DSC) measurements. Wide angle X‐ray diffraction (WXRD) analysis showed semi‐crystalline of the PCL and PCL‐co‐PDHCA polymers. The PCL‐co‐PDHCA copolymers showed good photoreactivities and fluorescent properties. Crosslinking of the cinnamoyl groups in the copolymers caused by UV irradiation affected the thermal stability and wettability slightly. Moreover, the hydrolysis experiments revealed that copolymers are facile degradable.
Preparation of Covalently‐colored Polymer Latex via Batch Emulsion Polymerization
Authors: Li Botian , Shen Jie , Ji Wenjiao , Cheng Guanzhi , Kan Chengyou
Published: October 2012

Covalently‐colored polymer latex was synthesized via batch emulsion copolymerization of styrene, butyl acrylate and methacrylic acid in the presence of red polymerizable dye monomer consisting of anthraquinone chromophore, alkyl spacer and acryloyl group, and the influences of the initiator, surfactant and polymerizable dye on the polymerization and the latex properties were investigated. Results showed that the initiator amount was a determinative factor for the monomer conversion, and a high conversion of the polymerizable dye could be achieved when the ammonium persulfate amount was equal to or more than 1 wt% to the total monomers. Most of the chromophores were covalently bonded to the polymer chains if the polymerizable dye was used in the range of 0–1.5 wt%. The light fastness of the resulting latex film was much better than that of the noncovalently‐colored polymer film.
Highly Efficient CN Bond Forming Reactions in Water Catalyzed by Copper(I) Iodide with Calix[4]arene Supported Amino Acid Ionic Liquid
Authors: Huang Li , Jin Can , Su Weike
Published: October 2012

A novel and effective protocol has been developed for the Ullmann‐type CN coupling reaction catalyzed by calix[4]arene supported amino acid ionic liquid and copper(I) iodide in water under microwave irradiation condition. The protocol uses calix[4]arene supported amino acid ionic liquid as double function of the ligand and phase‐transfer catalyst, and shows good tolerance in good to excellent yields.
Iodine‐Mediated Thioetherification of Alcohols with Disulfides or NaSH under Microwave Irradiation
Authors: Hu Bolun , Hu Huanan , Sun Leilei , Tang Riyuan
Published: October 2012

An efficient and novel method for the thioetherification of an alcohol with disulfides or NaSH under microwave irradiation is presented. In the presence of iodine, a variety of alcohols were smoothly S‐alkylated with disulfides or NaSH to give the corresponding thioethers in moderate to excellent yields.
Rural‐urban disparities in health status among US cancer survivors
Authors: Weaver Kathryn E. , Geiger Ann M. , Lu, Lingyi , Case L. Douglas
Published: October 2012

BACKGROUND:

Although rural residents are more likely to be diagnosed with more advanced cancers and to die of cancer, little is known about rural‐urban disparities in self‐reported health among survivors.

METHODS:

The authors identified adults who had a self‐reported history of cancer from the National Health Interview Survey (2006‐2010). Rural‐urban residence was defined using US Census definitions. Logistic regression with weighting to account for complex sampling was used to assess rural‐urban differences in health status after accounting for differences in demographic characteristics.

RESULTS:

Of the 7804 identified cancer survivors, 20.8% were rural residents. This translated to a population of 2.8 million rural cancer survivors in the United States. Rural survivors were more likely than urban survivors to be non‐Hispanic white (P < .001), to have less education (P < .001), and to lack health insurance (P < .001). Rural survivors reported worse health in all domains. After adjustment for sex, race/ethnicity, age, marital status, education, insurance, time since diagnosis, and number of cancers, rural survivors were more likely to report fair/poor health (odds ratio, 1.39; 95% confidence interval, 1.20‐1.62), psychological distress (odds ratio, 1.23; 95% confidence interval, 1.00‐1.50), ≥2 noncancer comorbidities (odds ratio, 1.15; 95% confidence interval, 1.01‐1.32), and health‐related unemployment (odds ratio, 1.66; 95% confidence interval, 1.35‐2.03).

CONCLUSIONS:

The current results provide the first estimates of the proportion and number of US adult cancer survivors who reside in rural areas. Rural cancer survivors are at greater risk for a variety of poor health outcomes, even many years after their cancer diagnosis, and should be a target for interventions to improve their health and well being. Cancer 2013. © 2012 American Cancer Society.
Development of a Liquid Chromatography/Amperometric Detection Method for the Determination of Multiresidue Sulfonamide Antibiotics in Meat‐Based Baby Foods
Authors: Casella Innocenzo G. , Contursi Michela , Gioia Daniele
Published: October 2012

Sulfonamides were oxidized at a polycrystalline gold electrode in neutral buffered phosphate medium at pH 7 and the electrochemical behavior was investigated using cyclic voltammetry technique. A liquid chromatography methodology based on the C18 reverse phase for the simultaneous separation of nine sulfamides, was studied and optimized. The amperometric detector using a polycrystalline gold substrate as working electrode and operating under pulsed amperometric detection mode (PAD) was tested for the determination of the selected molecules. Under optimal chromatographic and amperometric conditions, the limit of detection of the investigated sulfamides are comprised between 1 µM and 0.05 µM and the dynamic linear range spanned generally over three orders of magnitude. A liquid extraction procedure based on the use of acetonitrile solvent was tested and proposed for the quantitative extraction of sulfonamides from homogenized meat samples. The analytical method was successful tested for the determination of sulfonamides in homogenized meat‐based baby foods with reproducibility and recovery levels ranged between 5.0 % and 7.6 %. and 86 %–106 %, respectively.
Early Childhood Mental Health Consultation: Promoting Change in the Quality of Teacher–Child Interactions
Authors: Amini Virmani Elita , Masyn Katherine E. , Thompson Ross A. , Conners‐Burrow Nicola A. , Whiteside Mansell Leanne
Published: October 2012

The goal of this study was to examine the relationship between characteristics of early childhood mental health consultation (ECMHC) and changes in the quality of teacher–child interactions. One hundred forty‐one early childhood teachers, serving 3‐ to 5‐year‐olds in publically funded early education programs in the state of Arkansas, participated in this study. All childcare sites and preschool programs participating in the study received ECMHC through the Arkansas Early Childhood Mental Health Consultation Project over a period of 3 years. Findings from this study suggest that teachers exposed to ECMHC through their employment at one of the project sites made significant gains toward high‐quality teacher–child interactions relative to their initial levels of quality. In particular, delivery aspects of ECMHC and teachers’ experiences of ECMHC predicted change in quality of teacher–child interactions. Findings suggest that ECMHC may be a promising professional development intervention for teachers in early childhood settings and that specific characteristics of consultation may be particularly influential in impacting change in those settings.
The Similarities and Differences in the Work Experience of Women Faculty in Traditional and Nontraditional Disciplines
Authors: Xu Yonghong Jade
Published: October 2012

A better understanding of the professional life of women faculty is gained by comparing the work experiences of two subgroups: those working in disciplines considered “traditional” for women and those working in “nontraditional” disciplines.
Emotional Management and Motivation: A Case Study of Underrepresented Faculty
Authors: Lechuga Vicente M.
Published: October 2012

In this chapter, a qualitative inquiry about the emotional management of minority faculty in a science department illustrates the value of qualitative methodology in conducting institutional research.
Effect of Ni(II) on inflammatory gene expression in THP1 monocytic cells
Authors: Li Lei , Drury Jeanie L. , Zhang Hai , Sun Jianxun , DiJulio Dennis , Chung Whasun O. , Wataha John C.
Published: October 2012

Nickel‐containing alloys are in common use for dental restorations, but tend to corrode and release Ni(II) in service. Ni(II) increases secretion of several inflammatory cytokines from activated monocytic cells, suggesting that nickel alloys may exaggerate inflammatory responses in adjacent periodontal tissues. In this work, the effects of Ni(II) on expression of inflammatory cytokine and receptor genes as well as nuclear factor‐kappa B (NFκB)‐related genes were assessed using quantitative real‐time polymerase chain reaction (PCR) and PCR‐based arrays in the human THP1 monocytic cell line pre‐exposed to Ni(II) for 72 h, then activated by lipopolysaccharide. The expression of 10 inflammatory genes was down‐regulated ≥50% by Ni(II) versus non‐Ni(II) controls, whereas some genes like IL8 were up‐regulated significantly by Ni(II). Expression of seven NFκB‐related genes was up‐regulated by Ni(II) by ≥50%, and HMOX1 expression, a redox protein regulated by NRF2, was increased by >500%. The current results suggest that Ni(II) has diverse effects on inflammatory gene expression, which may partly account for previous reports of Ni(II)‐induced changes in inflammatory cytokine secretion from monocytes and alterations in NFκB regulation. Further work is needed to verify these effects in primary cells and to ascertain how Ni(II) alters gene expression. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 101A: 902–908, 2013.
Tumor necrosis factor‐α promotes bile ductular transdifferentiation of mature rat hepatocytes in vitro
Authors: Nishikawa Yuji , Sone Masayuki , Nagahama Yasuharu , Kumagai Eriko , Doi Yuko , Omori Yasufumi , Yoshioka Toshiaki , Tokairin Takuo , Yoshida Masayuki , Yamamoto Yohei , Ito Akihiko , Sugiyama Toshihiro , Enomoto Katsuhiko
Published: October 2012

We previously showed that mature hepatocytes could transdifferentiate into bile ductular cells when placed in a collagen‐rich microenvironment. To explore the mechanism of transdifferentiation, we examined whether inflammatory cytokines affected the phenotype of hepatocytes in a three‐dimensional culture system. Spheroidal aggregates of rat hepatocytes were embedded within a type I collagen gel matrix and cultured in the presence of various cytokines. In the control, hepatocytes gradually lost expression of albumin, tyrosine aminotransferase, and hepatocyte nuclear factor (HNF)‐4α, while aberrantly expressed bile ductular markers, including cytokeratin 19 (CK 19) and spermatogenic immunoglobulin superfamily (SgIGSF). Among the cytokines examined, tumor necrosis factor (TNF)‐α inhibited expression of albumin and HNF‐4α, both at mRNA and protein levels. After culturing for 2 weeks with TNF‐α, hepatocytic spheroids were transformed into extensively branching tubular structures composed of CK 19‐ and SgIGSF‐positive small cuboidal cells. These cells responded to secretin with an increase in secretion and expressed functional bile duct markers. TNF‐α also induced the phosphorylation of Jun N‐terminal kinase (JNK) and c‐Jun, and the morphogenesis was inhibited by SP600125, a specific JNK inhibitor. Furthermore, in chronic rat liver injury induced by CCl4, ductular reaction in the centrilobular area demonstrated strong nuclear staining of phosphorylated c‐Jun. Our results demonstrate that TNF‐α promotes the ductular transdifferentiation of hepatocytes and suggest a role of TNF‐α in the pathogenesis of ductular reaction. J. Cell. Biochem. 114: 831–843, 2013. © 2012 Wiley Periodicals, Inc.
Feasibility of arterial spin labeling on a 1T open MRI scanner
Authors: Heijtel Dennis F.R. , van Osch Matthias J.P. , Caan Matthan W.A. , Majoie Charles B. , vanBavel Ed , Nederveen Aart J.
Published: October 2012

Purpose:

To determine the clinical feasibility of arterial spin labeling (ASL) on a 1T open bore scanner.

Materials and Methods:

First, the optimal postlabeling delay (PLD) at 1T was determined (n = 5), with and without vascular crushing. Second, the effect of different labeling approaches (pseudo‐continuous ASL [pCASL] vs. pulsed ASL [PASL]), background suppression (BSup) and readout options (GRASE vs. EPI) was investigated (n = 9). Each effect was quantified by calculating the signal‐to‐noise ratio (SNR), convergence, and number of significant gray matter (GM) voxels in the ASL images. Finally, an example of an obese volunteer who could not have been scanned in a cylindrical scanner is presented.

Results:

The optimal PLDs were found to be 1300 msec for pCASL with and without vascular crushing. pCASL labeling outperformed PASL labeling in terms of convergence, anatomical correspondence between GM and perfusion maps, and SNR (P < 0.05). BSup appeared to have no additional value on the convergence, anatomical GM correspondence, and SNR (P > 0.05). EPI readout yielded a slightly better convergence, while the SNR of the GRASE readout was higher (P < 0.05).

Conclusion:

ASL on 1T is clinically feasible using state‐of‐the‐art sequences that were primarily developed for higher field strengths. J. Magn. Reson. Imaging 2013;37:958–964. © 2012 Wiley Periodicals, Inc.
Evaluating quantitative approaches to dynamic susceptibility contrast MRI among carotid endarterectomy patients
Authors: Crane David E. , Donahue Manus J. , Chappell Michael A. , Sideso Ediri , Handa Ashok , Kennedy James , Jezzard Peter , MacIntosh Bradley J.
Published: October 2012

Purpose:

To evaluate two dynamic susceptibility contrast (DSC) quantification methods in symptomatic carotid artery disease patients undergoing carotid endarterectomy (CEA) surgery by comparing methods directly and assessing the reliability of each method in the hemisphere contralateral to surgery.

Materials and Methods:

Absolute cerebral blood flow (CBF) and volume (CBV) was calculated in putamen and sensorimotor gray matter of 17 patients using two methods: 1) The Bookend method that scales relative DSC images to CBV values calculated from the ratio of pre‐ and postcontrast T1‐weighted images, and 2) the Tail‐scaling method that uses the ratio of area under the tails of the venous and arterial concentration time‐courses to scale the DSC images.

Results:

There was a positive correlation between the methods with significant correlation post‐CEA (P < 0.035). Intersession correlation was greater when using the Tail‐scaling method contralateral to surgery (P < 0.004).

Conclusion:

We have demonstrated correlation between methods that is significant after surgery and have found that the Tail‐scaling method produces better test–retest reliability than our implementation of the Bookend method. Results from this study suggest that DSC has the potential to measure hemodynamic changes after endarterectomy and future work is required to establish clinical value. J. Magn. Reson. Imaging 2013;37:936–943. © 2012 Wiley Periodicals, Inc.
Changes in apparent diffusion coefficient and T2 relaxation during radiotherapy for prostate cancer
Authors: Foltz Warren D. , Wu Andy , Chung Peter , Catton Charles , Bayley Andrew , Milosevic Michael , Bristow Robert , Warde Padraig , Simeonov Anna , Jaffray David A. , Haider Masoom A. , Ménard Cynthia
Published: October 2012

Purpose:

To evaluate regional and temporal changes in apparent diffusion coefficient (ADC) and T2 relaxation during radiation therapy (RT) in patients with low and intermediate risk localized prostate cancer.

Materials and Methods:

Seventeen patients enrolled on a prospective clinical trial where MRI was acquired every 2 weeks throughout eight weeks of image‐guided prostate IMRT (78 Gy/39 fractions). ADC and T2 quantification used entire prostate, central gland, benign peripheral zone, and tumor‐dense regions‐of‐interest, and mean values were evaluated for common response trends.

Results:

Overall, the RT responses were greater than volunteer measurement repeatability, and week 6 appeared to be an optimum time‐point for early detection. RT effects on the entire prostate were best detected using ADC (5–7% by week 2, P < 0.0125), effects on peripheral zone were best detected using T2 (19% reduction at week 6; P = 0.004) and effects on tumors were best detected using ADC (14% elevation at week 6; P = 0.004).

Conclusion:

ADC and T2 may be candidate biomarkers of early response to RT warranting further investigation against clinical outcomes. J. Magn. Reson. Imaging 2013;37:909–916. © 2012 Wiley Periodicals, Inc.
Predicting three‐dimensional patellofemoral kinematics from static imaging‐based alignment measures
Authors: Freedman Benjamin R. , Sheehan Frances T.
Published: October 2012

Patellofemoral pain syndrome causes significant discomfort and disability among much of the general population. Despite recent breakthroughs in dynamic three‐dimensional imaging technologies to assess pathological patellofemoral motion, such tools remain costly for clinical diagnostics applications. Thus, this study investigated whether three‐dimensional patellofemoral kinematics could be predicted from routine two‐dimensional static measures of patellofemoral joint alignment quantified from magnetic resonance imaging (MRI) data acquired in full knee extension. Twenty‐six volunteers clinically diagnosed with patellofemoral pain (19 F/7 M, 25.9 ± 11.1 years) and 26 control subjects (19 F/7 M, 25.3 ± 7.7 years) were included in this IRB‐approved study. Static three‐dimensional sagittal T1‐weighted gradient recall echo and dynamic MRI scans were acquired. For the dynamic image acquisition, subjects cyclically flexed and extended their knee (at 30 cycles/min) while a full cine‐phase contrast MRI set (24 time frames of anatomic images and x‐, y‐, and z‐velocity images) was acquired. From these data, static measures of patellofemoral alignment and three‐dimensional patellofemoral kinematics were derived. Single and multiple regressions between static and kinematic variables were evaluated. Although shown reliable, the static MRI measures could only partially predict patellofemoral kinematics, with r2‐values ranging from 16% to 77%. This makes it imperitave that the current precise, accurate, 3D, dynamic imaging techniques be translated into clinical tools. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31: 441–447, 2013
An orthopedic tissue adhesive for targeted delivery of intraoperative biologics
Authors: Simson Jacob , Crist Joshua , Strehin Iossif , Lu Qiaozhi , Elisseeff Jennifer H.
Published: October 2012

Tissue adhesives can bind together damaged tissues and serve as tools to deliver and localize therapeutics to facilitate regeneration. One emerging therapeutic trend in orthopedics is the use of intraoperative biologics (IOB), such as bone marrow (BM) and platelet‐rich plasma (PRP), to stimulate healing. Here, we introduce the application of the biomaterial chondroitin sulfate succinimidyl succinate (CS‐NHS) to deliver IOB in a hydrogel adhesive. We demonstrate the biomaterial's ability to bind various tissue types and its cellular biocompatibility with encapsulated human mesenchymal stem cells (hMSCs). Further, we examine in detail the CS‐NHS adhesive combined with BM aspirate for use in bone applications. hMSCs were encapsulated in CS‐BM and cultured for 5 weeks in osteogenic medium. Quantitative RT‐PCR demonstrated osteogenesis via upregulation of the osteogenic transcription factor Runx2 and bone markers alkaline phosphatase and osteocalcin. Significant deposition of calcium and osteocalcin was detected using biochemical, histological, and immunohistochemical techniques. Shear testing demonstrated that the CS‐BM adhesive exhibited an adhesive strength approximately an order of magnitude stronger than fibrin glue and approaching that of a cyanoacrylate adhesive. These results indicate that CS‐NHS is a promising delivery tool for IOB in orthopedic applications requiring a strong, degradable, and biocompatible adhesive that supports bone growth. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31: 392–400, 2013
Structural characterization of a third‐generation commercial cement superplasticizer by Raman spectroscopy and DFT calculations
Authors: Cañamares Maria Vega , Sanchez‐Cortes Santiago , Martinez‐Ramirez Sagrario
Published: October 2012

So far, the study of the structure of superplasticizers has been carried out on the main component of the cement admixture. This work presents the first structural Raman characterization of a superplasticizer in the complex matrix of a commercial product. In this case, a third‐generation (polycarboxylate based) superplasticizer was studied at various experimental conditions (excitation lines: 325, 445, 532, 633, 785, and 1064 nm; and pH values from 3 to 13). The best results were obtained by using the Fourier transformed‐Raman technique. Density functional theory calculations at the B3LYP/6‐31 G** level of theory were performed to aid in the characterization of the molecular structure of the superplasticizer. The structure of several models with the general structure of polycarboxylates was optimized and the Raman spectra were calculated. Finally, two different structures of the third‐generation superplasticizer were determined by comparison of the experimental Raman spectra with the calculated ones. Copyright © 2012 John Wiley & Sons, Ltd.
Depth‐resolved micro‐Raman spectroscopy of tri‐layer PFSA membrane for PEM fuel cells: how to obtain reliable inner water contents
Authors: Peng Z. , Huguet P. , Deabate S. , Morin A. , Sutor A. K.
Published: October 2012

Raman depth‐profiling microspectroscopy is currently emerging as a fast and non‐invasive method for the local content measurement of water diffusing across the perfluorosulfonic acid polymer used as electrolyte in low‐temperature fuel cells. However, water depth profiles obtained thereby are affected by the gradual degradation of the Raman signal as the exciting radiation is focused deeper into the sample and, thus, usually exhibit artificial gradients. The appropriate way to rectify raw data, in order to measure reliable inner water contents, is discussed in the case of perfluorosulfonic acid membranes soaked in water. The method is tested on a tri‐layer material composed by stacked ionomers with different chemical composition, ionic exchange capacity and swelling. Comparison of Raman spectra of the different ionomers, obtained under strictly the same hydration and optical conditions, allows critical discussion of previously reported band assignments. It is shown that Raman bands arising from the polymer backbone and from the side chain can be readily discriminated. Reliable water concentration profiles can then be obtained from the ratio between the Raman signal of sorbed water and of the polymer phase. Comparison with depth profiles obtained by using the pure water signal as internal reference shows that quantitative measurement requires the careful choice of the adequate Raman bands for representing the ionomer occupation of the volume probed by the exciting radiation. Different to what usually performed, the ionomer Raman signal to be integrated for compensating optical losses should include both bands arising from the polymer backbone and side chains. Last, obtaining accurate water concentration profiles also needs the knowledge of the so‐called optical factor β, i.e. the ratio between the scattering cross sections of ionomer chemical groups and sorbed water, which has to be measured by independent Raman experiments. Copyright © 2012 John Wiley & Sons, Ltd.
Effect of gender (barrows vs. females) on carcass traits and meat quality of Celta pig reared outdoors
Authors: Franco Daniel , Lorenzo José M
Published: October 2012

BACKGROUND: Today, the Celta is the unique indigenous pig breed of Galicia (northwest Spain), included in the Official Catalogue of Breeds of Spain as being in danger of extinction. The objective of this study was to estimate the effect of gender (barrows vs. female) on carcass traits and meat quality of Celta pig reared outdoors. The differences in carcass and meat quality between castrated barrows and gilts (n = 20), reared outdoors and slaughtered at a live weight of 140 kg, were determined.

RESULTS: The mean carcass weight was 108 kg and killing out percentage and chilling losses did not differ (P > 0.05) between genders, with a mean value of 78.2% and 2.68%, respectively. There were no statistical differences in the morphometric parameters between genders except for the leg length (LL) (P < 0.01), and hand length (HL) and ham length (Hml) (P < 0.001), which were greater in barrows. Gender affected significantly pH (5.67 vs. 5.55; P < 0.05) and moisture content (73.2% vs. 72.0%; P < 0.05), while intramuscular fat (IMF) did not differ significantly between genders (2.12% vs. 1.67%, P > 0.05) for barrows and females, respectively. No significant effect (P > 0.05) on parameters measured by Warner–Braztler (WB) test (shear force, firmness and total work of cut) was found, whereas textural profile analysis showed significant differences for all traits determined due to gender effect. Sensory evaluation of longissimus dorsi (LD) samples showed significant differences between genders in odour and taste traits. Finally, there were no significant differences (P > 0.05) in any amino acid concentrations between genders.

CONCLUSION: Values for carcass parameters indicated that Celta pigs produced very similar carcasses to those obtained from other rustic pigs. The percentage of 'noble' cuts relative to carcass weight was higher in barrows than in females. Finally, gender appeared to have little effect on the colour, textural organoleptic traits or amino acid profile of this breed of pig. © 2012 Society of Chemical Industry
Hybrid Organic‐Inorganic Membranes on Porous Supports by Size Exclusion and Thermal Sintering of Fluorescent Polyphenylsilsesquioxane Nanoparticles
Authors: Li Zhe , Tolbert Stephanie , Loy Douglas A.
Published: October 2012

Hybrid organic–inorganic membranes were prepared by size‐exclusion deposition and thermal sintering of fluorescent polyphenylsilsesquioxane nanoparticles on a ceramic support. Fluorescent polyphenylsilsesquioxane particles were prepared by a two‐step co‐polymerization of phenyltriethoxysilane with 0.1 mol‐% N‐(triethoxysilylpropyl)dansylamide. Because they were larger than the pores in the support, the particles formed a layer on top of the ceramic support that was sintered at 300 °C into a homogeneous, non‐porous membrane. Fluorescence of the modified polyphenylsilsesquioxane provided a valuable tool to monitor particle deposition and assist in characterization of the membranes.

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Synthesis and Characterization of Poly(ethylene glycol) Methacrylate Based Hydrogel Networks for Anti‐Biofouling Applications
Authors: Lei Jing , Mayer Christian , Freger Viatcheslav , Ulbricht Mathias
Published: October 2012

A series of hydrogels based on poly(ethylenglycol) methyl ether methacrylate (PEGMEMA) is synthesized using macromonomers of three different molecular weights, in combination with varied degrees of chemical crosslinking. The effects of PEGMEMA, initiator, and crosslinker concentrations on gel yield and swelling properties are studied. In addition, the chemical structure of the gels is characterized by FTIR and solid‐state NMR spectra. The swelling and rheological behaviors of hydrogels as well as protein partitioning into the gels are discussed in terms of the network mesh size. Low protein sorption and bacteria deposition tendencies indicate that PEGMEMA‐based hydrogels could be highly beneficial for uses as fouling‐resistant materials, for instance, as protective coatings for desalination membranes.

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Recent developments of proton‐transfer reaction mass spectrometry (PTR‐MS) and its applications in medical research
Authors: Zhan Xuefang , Duan Jiana , Duan Yixiang
Published: October 2012

Proton‐transfer reaction mass spectrometry (PTR‐MS) allows for real‐time, on‐line determination of absolute concentrations of volatile organic compounds (VOCs) with a high sensitivity and low detection limits (in the pptv range). The technique utilizes H3O+ ions for proton‐transfer reactions with many common VOCs while having little to no reaction with any constituents commonly present in air. Over the past decades, research has greatly improved the applications and instrumental design of PTR‐MS. In this article, we give an overview of the development of PTR‐MS in recent years and its application in medical research. The theory of PTR‐MS and various methods for discriminating isobaric VOCs are also described. We also show several specialized designs of sample inlet system, some of those may make PTR‐MS suitable for the detection of aqueous solution and/or non‐volatile samples. © 2012 Wiley Periodicals, Inc., Mass Spec Rev 32:143–165, 2013