bluuebunny/crossref_metadata_2025 huggingface dataset:
Bringing PROMIS to practice: Brief and precise symptom screening in ambulatory cancer care
Authors: Wagner Lynne I. , Schink Julian , Bass Michael , Patel Shalini , Diaz Maria Varela , Rothrock Nan , Pearman Timothy , Gershon Richard , Penedo Frank J. , Rosen Steven , Cella David
Published: November 2014

BACKGROUND

Supportive oncology practice can be enhanced by the integration of a brief and validated electronic patient‐reported outcome assessment into the electronic health record (EHR) and clinical workflow.

METHODS

Six hundred thirty‐six women receiving gynecologic oncology outpatient care received instructions to complete clinical assessments through Epic MyChart, an EHR patient communication portal. Patient Reported Outcomes Measurement Information System (PROMIS) computer adaptive tests (CATs) were administered to assess fatigue, pain interference, physical function, depression, and anxiety. Checklists identified psychosocial concerns, informational and nutritional needs, and risk factors for inadequate nutrition. Assessment results, including PROMIS T scores with documented severity thresholds, were immediately populated in the EHR. Clinicians were notified of clinically elevated symptoms through EHR messages. EHR integration was designed to provide automated triage to social work providers for psychosocial concerns, to health educators for information, and to dietitians for nutrition‐related concerns.

RESULTS

Four thousand forty‐two MyChart messages sent, and 3203 (79%) were reviewed by patients. The assessment was started by 1493 patients (37%), and once they started, 93% (1386 patients) completed the assessment. According to first assessments only, 49.8% of the patients who reviewed the MyChart message completed the assessment. Mean PROMIS CAT T scores indicated a lower level of physical function and elevated anxiety in comparison with the general population. Fatigue, pain, and depression scores were comparable to those of the general population. Impaired physical functioning was the most common basis for clinical alerts and occurred in 4% of the patients.

CONCLUSIONS

PROMIS CATs were used to measure common cancer symptoms in routine oncology outpatient care. Immediate EHR integration facilitated the use of symptom reporting as the basis for referral to psychosocial and supportive care. Cancer 2015;121:927–934. © 2014 American Cancer Society.
Impact of colorectal cancer diagnosis and treatment on health‐related quality of life among older Americans: A population‐based, case‐control study
Authors: Quach Caroleen , Sanoff Hanna K. , Williams Grant R. , Lyons Jessica C. , Reeve Bryce B.
Published: November 2014

BACKGROUND

Data on health‐related quality of life (HRQoL) changes among Americans aged ≥65 following colorectal cancer (CRC) diagnosis and treatment are limited. This study compared HRQoL changes among CRC patients across stages from before to after diagnosis with matched noncancer controls.

METHODS

This population‐based study used the Surveillance, Epidemiology, and End Results Medicare Health Outcomes Survey (MHOS) data set (1998‐2007). Medicare Advantage beneficiaries diagnosed with CRC between their baseline and follow‐up MHOS (n = 349) were matched to noncancer controls (n = 1745) using propensity scores. Mixed‐effects analysis of covariance models estimated changes in HRQoL (measured by the Medical Outcomes Study Short Form‐36/Veterans RAND 12‐item Survey) and the ability to perform 6 activities of daily living (ADLs) between baseline and follow‐up. Logistic regression models estimated odds ratios for ADL impairments and major depressive disorder (MDD) risk.

RESULTS

Mean time between CRC diagnosis and follow‐up MHOS was 12.3 ± 9.8 months. Compared with controls, CRC patients had significantly lower scores in all physical and mental health domains at follow‐up. The greatest decrements were observed in physical health and were largely driven by declines in the 6 months postdiagnosis and in stage III and IV patients. At follow‐up, CRC patients had greater overall ADL impairment and difficulty with dressing, eating, and getting in/out of chairs. CRC patients, particularly stage IV patients, had greater odds of being at risk for MDD relative to controls.

CONCLUSIONS

This study further underscores the adverse effects of CRC on physical health and the need to support older Americans' basic self‐care needs, with attention to later‐stage patients' increased debility. Cancer 2015;121:943–950. © 2014 American Cancer Society.
Experiencing reproductive concerns as a female cancer survivor is associated with depression
Authors: Gorman Jessica R. , Su H. Irene , Roberts Samantha C. , Dominick Sally A. , Malcarne Vanessa L.
Published: November 2014

BACKGROUND

Young adult female cancer survivors have unmet reproductive concerns and informational needs that are associated with poorer quality of life. The purpose of this study was to examine the association between current reproductive concerns and moderate to severe depression among young survivors.

METHODS

This cross‐sectional study included 200 female cancer survivors between the ages of 18 and 35 years who completed a Web‐based survey measuring reproductive history, parenthood desires, reproductive concerns after cancer, and quality‐of‐life indicators.

RESULTS

The mean age of the participants was 28 years (standard deviation, 4.4 years), and almost two‐thirds were diagnosed within 5 years of survey completion. A multivariate logistic regression analysis controlling for education, duration of survivorship, and social support revealed an association between experiencing reproductive concerns and moderate to severe depression (odds ratio for each 5‐unit increase in the Reproductive Concerns After Cancer [RCAC] score, 1.30; 95% confidence interval, 1.06‐1.60). Among those with moderate to severe depression, 23% had high RCAC scores, whereas 6% of those with minimal to mild depression did (P < .001).

CONCLUSIONS

A higher level of reproductive concerns was associated with greater odds of experiencing moderate to severe depression. Almost a quarter of survivors in this sample reported moderate to severe depression, and addressing reproductive concerns represents one potential area of intervention for improving the psychosocial health of young survivors. Cancer 2015;121:935–942. © 2014 American Cancer Society.
Significant association between human osteosarcoma and simian virus 40
Authors: Mazzoni Elisa , Benassi Maria Serena , Corallini Alfredo , Barbanti‐Brodano Giovanni , Taronna Angelo , Picci Piero , Guerra Giovanni , D'Agostino Antonio , Trevisiol Lorenzo , Nocini Pier Francesco , Casali Maria Vittoria , Barbanti‐Brodano Giuseppe , Martini Fernanda , Tognon Mauro
Published: November 2014

BACKGROUND

Simian virus 40 (SV40) has been considered to be an oncogenic viral agent in the development of osteosarcoma (OS), which to the authors' knowledge continues to be of unknown etiology.

METHODS

In the current study, serum samples from patients with OS were investigated with an indirect enzyme‐linked immunoadsorbent assay (ELISA) to test for the presence of immunoglobulin G antibodies, which react with SV40 antigens. In ELISA, SV40 antigens were represented by 2 synthetic polypeptides that mimic epitopes of the viral capsid proteins 1 to 3. Additional sera from patients with breast cancer and undifferentiated nasopharyngeal carcinoma as well as healthy subjects were the controls.

RESULTS

Immunologic results suggested that antibodies that react with SV40 mimotopes were more prevalent (44%) in serum samples from patients with OS compared with healthy subjects (17%). The difference in prevalence between these cohorts was statistically significant (P<.001). It is interesting to note that in the patients with OS, significance indicated the difference between OS versus breast cancer (44% vs 15%; P<.001) and OS versus undifferentiated nasopharyngeal carcinoma (44% vs 25%; P<.05).

CONCLUSIONS

The data from the current study indicate an association between OS and SV40. These data could be transferred to clinical applications for innovative therapies to address SV40‐positive OS. Cancer 2015;121:708–715. © 2014 American Cancer Society.
One‐Step Synthesis and Polyacrylic Acid Functionalization of Multifunctional Europium‐Doped NaGdF4 Nanoparticles with Selected Size for Optical and MRI Imaging
Authors: Nuñez Nuria O. , García María , García‐Sevillano Jorge , Rivera‐Fernández Sara , de la Fuente Jesús M. , Ocaña Manuel
Published: November 2014

Multifunctional Eu:NaGdF4 nanospheres functionalized with polyacrylic acid (PAA) polymer have been prepared for the first time by a simple one‐pot method that consists of a homogeneous precipitation reaction at 120 °C. The size of the nanospheres, which were polycrystalline and crystallized into a hexagonal structure, could be altered in the 60–95 nm range by adjusting the amount of polyacrylic acid added. The effects of Eu content and particle size of these nanomaterials on their optical properties (emission intensity and lifetime) as well as on their relaxivity (r1 and r2) values were also analyzed to find the optimum system for optical bioimaging and as a positive contrast agent for magnetic resonance imaging (MRI) applications. Finally, such optimum nanoparticles showed negligible cytotoxicity for Vero cells for concentrations up to 0.5 mg mL–1 and a high colloidal stability in 2‐morpholinoethanesulfonic acid solutions, thereby satisfying the most important requirements for their use in biotechnological applications.
Automated Determination of Cu(II), Pb(II), Cd(II) and Zn(II) in Environmental Samples by Square Wave Voltammetry Exploiting Sequential Injection Analysis and Screen Printed Electrodes
Authors: Ribeiro Luiz Fernando , Masini Jorge Cesar
Published: November 2014

This paper describes the development of a methodology for quantification of Cu(II), Pb(II), Cd(II) and Zn(II) in waters and sediments by anodic stripping voltammetry (ASV) automated by Sequential Injection Analysis (SIA) using a graphite screen printed sensor modified with mercury. Determinations were made by standard addition automated by the SIA system. The limits of detection and quantification were, respectively, 1.3 and 4.3 µg L−1 for Cu(II), 1.4 and 4.6 µg L−1 for Pb(II), 0.6 and 1.8 µg L−1 for Cd(II) and 4.2 and 14 µg L−1 for Zn(II). These limits were obtained for a sample volume of 1000 µL, flow rate of 10 µL s−1 (during the deposition step), and utilizing 3 flow reversals (volume of reversion=950 µL), totalizing a deposition time of 315 s. The potentiostat worked synchronically with the SIA system applying the conditioning potential of −0.1 V vs. pseudo reference of Ag (100 s), deposition potential of −1.0 V for Cu(II), Pb(II) and Cd(II) or −1,3 V for Zn(II), square wave frequency of 100 Hz, potential step of 6 mV and pulse height of 40 mV. For quantification of Zn(II) in sediment extracts, deposition of Ga0 on the working electrode was necessary to avoid the formation of intermetallic between Zn0 and Cu0. The accuracy of the method was assessed by spike and recovery experiments in water samples which resulted recovery rates near 100 % of the spiked concentrations. Recoveries of concentrations in the certified sediment sample CRM‐701 undergoing the three steps sequential extraction procedure of BCR varied from 71.7 % for Zn(II) in the acetic acid extract to 112.4 % for Cu(II) in the oxidisable fraction, confirming that the standard addition approach corrected the matrix effects in the complex samples of sediment extracts.
Activity‐Related Parenting Practices: Development of the Parenting Related to Activity Measure (PRAM) and Links with Mothers' Eating Psychopathology and Compulsive Exercise Beliefs
Authors: Haycraft Emma , Powell Faye , Meyer Caroline
Published: November 2014

This is a two‐study paper that developed a measure to assess parenting practices related to children's physical activity and explored maternal predictors of such parenting practices. Study 1: A self‐report measure of parents' activity‐related practices (the Parenting Related to Activity Measure) was developed, and a principal component analysis was carried out using data from 233 mothers of 4.5‐ to 9‐year‐old children. The results supported a six‐factor model and yielded the following subscales: Responsibility/monitoring; Activity regulation; Control of active behaviours; Overweight concern; Rewarding parenting; and Pressure to exercise. Study 2: Mothers (N = 170) completed the Parenting Related to Activity Measure, alongside measures of eating psychopathology and compulsive exercise, to identify predictors of activity‐related parenting practices. Mothers' eating psychopathology and exercise beliefs predicted activity parenting practices with their sons and daughters, but different predictors were seen for mothers of daughters versus sons. Mothers' eating and exercise attitudes are important predictors of their activity‐related parenting practices, particularly with girls. Identifying early interactions around activity/exercise could be important in preventing the development of problematic beliefs about exercise, which are often a key symptom of eating disorders. Copyright © 2014 John Wiley & Sons, Ltd and Eating Disorders Association.
An integrated assessment of habitat quality of national estuarine research reserves in the southeastern United States
Authors: Balthis W Leonard , Cooksey Cynthia , Fulton Michael F , Hyland Jeffrey L , Riekerk George HM , Van Dolah Robert F , Wirth Edward F
Published: November 2014

Multiple indicators of water quality, sediment quality, and biological condition were used to assess the status of ecological condition of National Estuarine Research Reserve System (NERRS) sites in North Carolina, South Carolina, and Georgia relative to a suite of corresponding scoring criteria. All measurements were made in subtidal aquatic habitats. Calculated scores were integrated into an overall index of habitat quality and used to make comparisons among the various NERR and nonNERR estuaries throughout the region. Sediment quality scores varied considerably among NERR sites, but in most cases were similar between individual NERR and non-NERR sites in corresponding states. Water quality and biological condition indicators scored consistently higher for NERRs versus non-NERR sites. Overall habitat quality scores also were consistently higher for NERRS sites, suggesting that these areas are on par with if not in slightly better condition ecologically than neighboring nonNERR estuaries. Portions of individual NERR sites rated as poor with respect to overall habitat quality were limited to relatively small areas (<13% of a reserve's total sampling area). Integr Environ Assess Manag 2015;11:266–275. Published 2014 SETAC. This article is a US Government work and, as such, is in the public domain in the USA.

Key Points

The approach described in this paper provides a method of integrating measurements of multiple indicators of water quality, sediment quality, and biological condition into a single habitat quality index. The ability to combine a suite of indicators into easily-interpretable, easy-to-understand index represents a powerful management tool. The results of this study suggest that protected areas such as National Estuarine Research Reserves (NERRs) are in relatively good shape in comparison to neighboring estuaries.
An integrated assessment for wind energy in Lake Michigan coastal counties
Authors: Nordman Erik , VanderMolen Jon , Gajewski Betty , Isely Paul , Fan Yue , Koches John , Damm Sara , Ferguson Aaron , Schoolmaster Claire
Published: November 2014

The benefits and challenges of onshore and offshore wind energy development were assessed for a 4-county area of coastal Michigan. Economic, social, environmental, and spatial dimensions were considered. The coastal counties have suitable wind resources for energy development, which could contribute toward Michigan's 10% renewable energy standard. Wind energy is cost-effective with contract prices less than the benchmark energy price of a new coal-fired power plant. Constructing a 100 MW wind farm could have a $54.7 million economic impact. A patchwork of township-level zoning ordinances regulates wind energy siting. Voluntary collaborations among adjacent townships standardizing the ordinances could reduce regulatory complexity. A Delphi Inquiry on offshore wind energy in Lake Michigan elicited considerable agreement on its challenges, but little agreement on the benefits to coastal communities. Offshore turbines could be acceptable to the participants if they reduced pollution, benefited coastal communities, involved substantial public participation, and had minimal impact on property values and tourism. The US Coast Guard will take a risk-based approach to evaluating individual offshore developments and has no plans to issue blanket restrictions around the wind farms. Models showed that using wind energy to reach the remainder of the 10% renewable energy standard could reduce SO2, NOx, and CO2 pollution by 4% to 7%. Turbines are highly likely to impact the area's navigational and defense radar systems but planning and technological upgrades can reduce the impact. The integrated assessment shows that responsible wind energy development can enhance the quality of life by reducing air pollution and associated health problems and enhancing economic development. Policies could reduce the negative impacts to local communities while preserving the benefits to the broader region. Integr Environ Assess Manag 2014;X:000–000. ©2014 SETAC Integr Environ Assess Manag 2015;11:287–297. © 2014 SETAC

Key Points

Michigan's coastal counties have wind resources that are suitable for utility-scale energy development. Wind energy is cost-effective with contract prices less than the benchmark energy price of a new coal-fired power plant. The integrated assessment shows that responsible wind energy development can enhance the quality of life by reducing air pollution and associated health problems and enhancing economic development. State and local policies could reduce the negative impacts to local communities while preserving the benefits to the broader region.
Improved depiction of Indian summer monsoon in latest high resolution NCEP climate forecast system reanalysis
Authors: Chaudhari Hemantkumar S. , Pokhrel Samir , Saha Subodh K. , Dhakate Ashish , Hazra Anupam
Published: November 2014

The improvements in representing the Indian summer monsoon features are assessed using the latest coupled global reanalysis, the climate forecast system reanalysis (CFSR) from National Centre for Environmental Predictions (NCEP) with respect to widely used NCEP‐reanalysis 2 (NCEP2). To validate the reanalysis product corresponding observations are also used. CFSR is more realistic in terms of spatial pattern of seasonal mean rainfall, first and second empirical orthogonal function (EOF) modes of interannual variability as compared with NCEP2 reanalysis. Percentage of total variance was explained by northward and westward propagating intraseasonal oscillation modes in CFSR that are better captured than those from NCEP2 reanalysis. Northward propagating mode is well depicted in CFSR as compared with that of NCEP2 and may be attributed to the strong vertical shear of zonal wind and strong meridional gradient of specific humidity in CFSR. Distribution of the north–south and east–west spectra of CFSR suggests much better conformity with observation as compared with NCEP2. Surface wind patterns of CFSR are having relatively small errors compared to Quick Scatterometer (QuikSCAT) winds. CFSR has some success in simulating observed sea surface temperature (SST)–rainfall relationship as well as in depicting the coupled ocean‐atmosphere phenomena of El Niño and Southern Oscillation (ENSO) in terms of Indian summer monsoon rainfall (ISMR) teleconnections. Overall monsoon features in CFSR are much closer to the observation as compared with NCEP2, and these may be because of the realistic representation of ocean–atmosphere feedback owing to the coupled model‐based reanalysis. This study will help in establishing the credibility of the CFSR in terms of realistic representation of Indian summer monsoon as compared with widely used atmospheric only reanalysis.
Food allergy, a summary of eight cases in the UK criminal and civil courts: effective last resort for vulnerable consumers?
Authors: Gowland M. Hazel , Walker Michael J
Published: November 2014

Food allergy has a forensic context. The authors describe eight cases in the UK courts involving fatalities, personal injury or criminal non‐compliance with food law from mainly ‘grey’ literature sources. The potentially severe consequences for people with food allergy of contraventions of labelling law have led to enforcement action up to criminal prosecution for what might otherwise be regarded as ‘trivial’ non‐compliance. The authors suggest there should be central collation of such cases. Non‐compliances should be followed up in a more rapid and robust manner. Evidence of fraud in the catering supply chain supports recent calls for zero tolerance of food fraud. Businesses must guard against gaps in allergen management, for which there are readily available sources of training and guidance, but also against fraudulent substitution in the supply chain, about which training and guidance should be developed. New allergen labelling legislation and case law appear to place responsibility on food businesses even for the forensically problematic area of allergen cross‐contamination. The courts can be an effective last resort for vulnerable consumers; however, there is evidence of knowledge and skill gaps in both the investigation and prosecution of potentially serious incidents of food allergen mismanagement and mislabelling. Thorough investigation of food allergy deaths is required with a tenacious and skilled approach, including early realisation that samples of the food and/or stomach contents from a post mortem examination should be retained and analysed. The supply chain must be rigorously examined to find out where adulteration or contamination with the fatal allergen occurred. © 2014 Society of Chemical Industry
Application of a nanostructured supramolecular solvent for the microextraction of diphenylamine and its mono‐nitrated derivatives from unburned single‐base propellants
Authors: Ferdowsi Mohammad , Taghian Abolfazl , Najafi Asghar , Moradi Morteza
Published: November 2014

A supramolecular solvent made up of nano‐sized inverted hexagonal aggregates of 1‐octanol is proposed for the microextraction of diphenylamine and its mono‐nitrated derivatives in unburned single‐base propellants. The procedure included the extraction of sub‐gram quantities (30 mg) of homogenized propellant with 1.5 mL of the supramolecular solvent. Several conditions affecting extraction efficiency, for example the concentrations of the major components of the supramolecular solvent (tetrahydrofuran and alkanol), alkanol type, solvent pH, and extraction time, were investigated and optimized. The main forces for the microextraction of analytes in the nanostructured supramolecular solvent include both dispersion and hydrogen bond interactions. This mixed‐mode mechanism resulted in high extraction efficiencies reaching low method detection limits (0.005–0.012 mg/g) without the need for extract evaporation. Under the optimum conditions, recoveries in samples ranged between about 82.6 and 98.7%. Compared to the reference method, the proposed method is simple and rapid, delivering accurate and precise results, and can be applied for routine determination of diphenylamine and its derivatives in propellants. The precision of the method, expressed as relative standard deviation, was about 4.3–10.9%.
The mechanicochemical modification of high polymers
Authors: Ceresa R. J.
Published: November 2014

There is presented a review of the published work on gelatinization of polymers, polymers with fillers, mixed polymers, block copolymers, and polymers crosslinked by mechanical treatment. Some new applications of these mechanicochemical processes for elastomers, plastomers, resins, modified and nonmodified polymers are proposed and discussed. Systems such as natural rubber‐acenaphthalene, polymethyl methacrylate‐acrylonitrile, epoxide resin‐methyl methacrylate, starch‐styrene, and ethylcellulose‐polyvinylacetate have been characterized. A technique relating to the purification of polymer modified by copolymer which is usually present is given. The properties of polymers, modified by mechanicochemical processes (notably the systems mentioned above), are related to their chemical structure.
Effect of organic internal complexes of some metals of variable valence on the kinetics of polymerization of vinylic compounds
Authors: Szántó I. , Gál K.
Published: November 2014

Because of the important part played by variable valence metals in polymerization processes taking place in oxidation‐reduction systems it is very interesting to investigate the effect of these metals on polymerization processes occurring in a system not of an oxidation‐reduction nature. In the present study we have investigated the retarding action of iron, chromium, cobalt, manganese, and copper acetylacetonates on the polymerization of vinyl acetate, styrene, and methylmethacrylate. The greatest effect of these compounds was observed in the case of vinyl acetate polymerization. In the course of investigating the kinetics of this reaction we were able to shed light on the influence of aldehyde peroxide impurities on the polymerization process of pure vinyl acetate. Detailed kinetic investigations were also made on the polymerization of vinyl acetate from various sources. On one specimen of vinyl acetate measurements were made of the retarding effects of various concentrations of iron acetylacetonate at various temperatures of reaction. The activation energy of the retardation process was computed.

The results of our experiments showed that at concentrations of 1.0 × 105−5.0 × 10−6 mole/1 copper acetylacetonate was not an inhibitor but a strong retarder of the process. The retarding effect of copper benzoate was also investigated. It was found that copper linked through an ionic bond is a weak inhibitor.
Structure des Polyesters Durcis
Authors: Bohdanecký M. , Mleziva J. , Šternschuss A. , Zvonař V.
Published: November 2014

La copolymérisation du styrène avec des polyesters non‐saturés a été étudiée au moyen d'un procédé décrit précédemment. On a élucidé l'effet d'acides modificateurs non polymérisants (phthalique, succinique, endométhylène‐tétrahydrophtalique) sur la copolymérisation. On a aussi étudié l'effet d'affaiblissement des liens fumariques en rapport avec les quantités d'acides modificateurs, de styrène et de plastifiant et avec la longueur de la chaǐne glycolique. La concentration des groupes fumariques a toujours été trouvée moindre que celle prédite de la composition du mélange initial. La composition du copolymère dépend de la concentration en acide modificateur, de la longueur de la chaǐne glycolique et du poids moléculaire du polyester. Les différences sont attribuées à des effets stériques. Les résultats des études antérieures sont discutés de ce point de vue.
Les Combinaisons d'Insertion du Potassium dans le Graphite Utilisées Comme Catalyseurs de Polymérisation
Authors: Parrod J. , Beinert G.
Published: November 2014

Les métaux alcaline sont des initiateurs classiques de polymérisation. Le sodium et le potassium ont été utilisés depuis longtemps, a l'échelle industrielle, dans la fabrication du caoutchouc synthétique. L'emploi de lithium, quoique plus récent, a reçu une grande impulsion lors de la découverte de son action initiatrice dans la polymérisation de l'isoprene en un caoutchouc semblable au produit naturel. Nous avons trouvé que ces substances initient la polymérisation de nombreux monomères. Nous avons entrepris une étude comparative des produits formés à partir de styrène, de butadiène et d'isoprène. Les différences non encore expliquées sont de différences légères, sous le rapport de l'effet du potassium métal et des composés d'inclusion du type (C8K)n et (C24K)n. Polystyrènes: Nous sommes capables de montrer que les courbes de distribution du poids moléculaire de ces produite ont une certaine similitude (měme type d'équations). Cependant, il suit de cette étude que le potassium contenant des graphites facilite la formation de polymères avec des poids moléculaires plus élevés. Ainsi par exemple le poids moléculaire moyen d'une des fractions obtenues à l'aide du C24K atteint une valeur de 5 × 106. D'autre part, dans les trois cas de C8K, C24K et K, le degré de conversion n'était pas le měme et montrait que la vitesse de réaction diminue lorsqu'on utilise du potassium inclue dans du graphite, au lieu du potassium pur finement divisé. Le caractère hétérogène de la réaction est encore compliqué par le fait que le polymère enrobe le catalyseur. Plus important que le degré de conversion, est la concentration en monomère dans la masse solide. Polybutadiène: Une étude du spectre d'absorption infrarouge montre que dans les trois cas nous sommes eu présence de polymères à structures simultanées trans 1,2 et 1,4, mais pas à structures eis 1,4. La quantité relative de ces structures diffère d'un produit à l'autre. Da été montré par analyse quantitative de spectre d'absorption que le potassium contenant du graphite ne favorise pas la formation des structures 1,4. Isoprènes: Les structures des polymères obtenus dans ce cas avec les trois catalyseurs ont été déterminées comme dans le cas précédent. Le spectre d'absorption montre que l'addition a lieu en position trans 1,2, 1,3 et 1,4. Ici aussi aucune addition cis 1,4 n'a été montrée. Comme dans le cas du polybutadiène, une analyse quantitative des spectres montre que le potassium inclus dans du graphite ne favorise pas les structures 1,4. Il est remarquable que les graphites contenant du potassium et mélangés avec des quantités considérables de noir animal conservent leurs propriétés initiatrices de polymérisation (polymérisation de butadiène et de l'isoprene). Ceci suppose l'inclusion directe des particules chargées dans le polymère au cours de sa formation.
Réactions entre les Amines Aromatiques et le Polychlorure de Vinyle
Authors: Wolkober Z. , Holly T. , Thurzo G.
Published: November 2014

La réaction des amines aromatiques et du chlorure de polyvinyle n'est jusqu'à présent pas élucidée, puisque l'atome de chlore est trés fortement lié et qu'il existe par ailleurs une trés forte tendance à la décomposition intermoléculaire du PCV. En accord avec nos expériences, toutes les amines substituées à l'atome d'azote réagissent avec le PCV à des températures au‐dessus de 100°C. La composition de ces produits dépend de la durée et de la température de réaction ainsi que du rapport amine‐PCV. On peut produire une structure réticulaire par des petites quantités d'amines. Si les amines sont utilisées en quantités équimoléculaires ou en large excès, les produits peuvent ětre solubles dans l'alcool et l'acide acétique. Pour un excès d'amine mais à température plus basse, une décomposition partielle des chaǐnes de PCV a lieu avec un poids moléculaire de ±25.000 (mesuré par diffusion ou méthode de dialyse). Les produits subissent une diazotation et se combinent aux colorants. On a obtenu un colorant polyazique, qui pourrait servir comme matériel de coloration du PCV. Afin d'élucider, les cinétiques de la réaction entre l'aniline et le PCV, nous avons déterminé les valeurs des constante de vitesses de réaction à différentes températures. Ces expériences fournissent une énergie d'activation de la réaction plus petite lorsqu'il y a un excès d'aniline que pour le décomposition intermoléculaire du PCV. On a trouvé qu'une réaction similaire peut avoir lieu avec d'autres amines substitutées, mais que la vitesse dépend de la nature du substituant.
Grafting of methyl methacrylate to polypropylene and polyethylene
Authors: Lazár M. , Rado R. , Pavlineč J.
Published: November 2014

In a study of chemical modification of hydrocarbon polymers an investigation was made of the grafting of methyl methacrylate onto polypropylene and polyethylene. The grafting process was carried out both through preliminary polymer hydroperoxide formation and through chain transfer reactions. Polymer hydroperoxide‐induced grafting proceeds via direct free radical initiation of side chain growth and via hydrogen atom transfer from the hydrocarbon polymer to the polymethyl methacrylate radical. Here the contributions to the chain transfer from the initiator and the methyl methacrylate radical were determined for the separate polymers. Since the grafting was carried out in swollen polymers the effect of viscosity of the medium on the course of the grafting of methyl methacrylate was examined. During the grafting of methyl methacrylate to polyethylene and polypropylene the possibility of crosslinking of these polymers arises. Of particular interest is crosslinking of polypropylene, in view of the fact that the direct reaction induced by ionizing radiation or by hydroperoxide decomposition is connected with certain complications brought about by degradation of the polymer backbone. In the case in question, the formation of a crosslinked structure is due to recombination of the growing methyl methacrylate chains. The crosslinking of the graft polymer is hindered by the chain transfer reaction and by disproportionation during chain termination. In the case of methyl methacrylate, the ratio between recombination and disproportionation is favorable to crosslinkage of the graft polymers, a fact which has been confirmed experimentally. Based on the data concerning the chain transfer reactions and the conditions of formation and decomposition of polymer hydroperoxides a discussion has been presented of the most favorable procedures for grafting methyl methacrylate onto polypropylene and polyethylene and for the formation of crosslinked graft polymers.
Donor‐acceptor interactions in cationic polymerization. IV. Role of nonpolar compounds in the cationic polymerization of isobutylene
Authors: Zlámal Z. , Kazda A.
Published: November 2014

Comparison of changes in electrical conductivities and in molecular weight of polyisobutene produced in the medium studied shows that, as in the case of polar compounds, nonpolar compounds also affect the course of the cationic polymerization of isobutene, in the first place through their influence on the ionization of the active complex. The difference between hexane and benzene‐both having approximately the same dielectric constant‐shows that π‐electrons of the aromatic ring cause an increase of the specific conductivity of the system at low concentrations of the aromatic compounds; only at higher concentrations of benzene is there a decrease in the specific conductivity induced by a decrease in the dielectric constant. The dependence of the molecular weight of polyisobutene on the content of nonpolar compound is inversely proportional to the conductivity curve, which proves that the termination reaction in the case studied is a reaction involving free ions and not ion pairs.
Chemical interaction and mechanism of activation of binary systems of vulcanization accelerators
Authors: Dogadkin B. A. , Fel'dshteǐn M. S. , Belyaeva E. N.
Published: November 2014

The efficiency and mechanism of the combined action of vulcanization accelerators are considered from the standpoint of their chemical structure. An investigation of the vulcanization of various types of butadiene‐styrene and natural rubbers showed that double accelerator systems may be divided into three groups; namely: systems with mutual activation of the accelerators, systems with activation of one of the accelerators, and systems with additive action of the accelerators. The vulcanization kinetics of the first two (nonadditive) groups of accelerators differ from those for the separate application of the accelerators by a retardation in the initial period and a sharp increase in rate of the main period of the vulcanization process. During interaction of accelerators of which one contains the benzothiazolyl group and the other is a hydrogen donor the formation of 2‐mercaptobenzothiazole is observed. Formation of this compound may also be noted on interaction of the accelerators in the rubber medium, the yield in this case being considerably higher than on separate interaction of the accelerators with the rubber. In the presence of sulfur (disulfide‐sulfenamide or disulfide‐organic nitrogenous base systems) a considerable rise in the yield of 2‐mercaptobenzothiazole is observed, accompanied by the formation of hydrogen sulfide and its subsequent interaction with the disulfide. The activity of double accelerator systems is the higher, the more intensive the formation of 2‐mercaptothiazole. The mutual activation of the accelerators is explained by the formation of intermediate complexes, decomposing to free radicals that initiate the interaction between sulfur and rubber and polymerization processes of the latter. A scheme of such reactions is presented.
Destruction of poly‐ϵ‐caprolactam by an exchange reaction between amide linke
Authors: Wichterle O. , Šittler E. , Čefelin P.
Published: November 2014

The course of the cross amidation reaction in the system polycaprolactam‐low molecular amide has been followed by measuring changes in viscosity. Conversion curves were plotted from data on the decrease in viscosity of a solution of the polyamide in the low molecular amide at the reaction temperature. Conventional reagents for the hydrolytic and catalytic polymerization of the caprolactam were employed as catalysts.
ApoE: The role of conserved residues in defining function
Authors: Frieden Carl
Published: November 2014

The amino acid sequences of apolipoprotein E (apoE) from 63 different mammalian species have been downloaded from the protein database. The sequences were compared to human apoE4 to determine conserved and non‐conserved sequences of amino acids. ApoE4 is the major risk factor for the development of late onset Alzheimer's disease while apoE3, which differs from apoE4 by a single amino acid change at position 112, poses little or no risk for the development of this disease. Thus, the two proteins appear to be structurally and functionally different. Seven highly conserved regions, representing approximately 47 amino acids (of 299) have been found. These regions are distributed throughout the protein and reflect ligand binding sites as well as regions proposed to be involved in the propagation of the cysteine–arginine change at position 112 to distant regions of the protein in the N‐ and C‐terminal domains. Highly non‐conserved regions are at the N‐ and C‐terminal ends of the apoE protein.
Brief Reports: Controlling the Survival of Human Pluripotent Stem Cells by Small Molecule-Based Targeting of Topoisomerase II Alpha
Authors: Ben-David Uri , Cowell Ian G. , Austin Caroline A. , Benvenisty Nissim
Published: November 2014

Pluripotent-specific inhibitors (PluriSIns) make a powerful tool to study the mechanisms controlling the survival of human pluripotent stem cells (hPSCs). Here, we characterize the mechanism of action of PluriSIn#2, a compound that selectively eliminates undifferentiated hPSCs, while sparing various other cell types derived from them. Toxicogenomic analysis predicts this compound to be a topoisomerase inhibitor. Gene expression analyses reveal that one of the human topoisomerase enzymes, topoisomerase II alpha (TOP2A), is uniquely expressed in hPSCs: TOP2A is highly expressed in undifferentiated cells, is downregulated during their differentiation, and its expression depends on the expression of core pluripotency transcription factors. Furthermore, siRNA-based knockdown of TOP2A in undifferentiated hPSCs results in their cell death, revealing that TOP2A expression is required for the survival of these cells. We find that PluriSIn#2 does not directly inhibit TOP2A enzymatic activity, but rather selectively represses its transcription, thereby significantly reducing TOP2A protein levels. As undifferentiated hPSCs require TOP2A activity for their survival, TOP2A inhibition by PluriSIn#2 thus causes their cell death. Therefore, TOP2A dependency can be harnessed for the selective elimination of tumorigenic hPSCs from culture. Stem Cells  2015;33:1013–1019
TGF-β1, GDF-5, and BMP-2 Stimulation Induces Chondrogenesis in Expanded Human Articular Chondrocytes and Marrow-Derived Stromal Cells
Authors: Murphy Meghan K. , Huey Daniel J. , Hu Jerry C. , Athanasiou Kyriacos A.
Published: November 2014

Replacement of degenerated cartilage with cell-based cartilage products may offer a long-term solution to halt arthritis' degenerative progression. Chondrocytes are frequently used in cell-based FDA-approved cartilage products; yet human marrow-derived stromal cells (hMSCs) show significant translational potential, reducing donor site morbidity and maintaining their undifferentiated phenotype with expansion. This study sought to investigate the effects of transforming growth factor β1 (TGF-β1), growth/differentiation factor 5 (GDF-5), and bone morphogenetic protein 2 (BMP-2) during postexpansion chondrogenesis in human articular chondrocytes (hACs) and to compare chondrogenesis in passaged hACs with that of passaged hMSCs. Through serial expansion, chondrocytes dedifferentiated, decreasing expression of chondrogenic genes while increasing expression of fibroblastic genes. However, following expansion, 10 ng/mL TGF-β1, 100 ng/mL GDF-5, or 100 ng/mL BMP-2 supplementation during three-dimensional aggregate culture each upregulated one or more markers of chondrogenic gene expression in both hACs and hMSCs. Additionally, in both cell types, the combination of TGF-β1, GDF-5, and BMP-2 induced the greatest upregulation of chondrogenic genes, that is, Col2A1, Col2A1/Col1A1 ratio, SOX9, and ACAN, and synthesis of cartilage-specific matrix, that is, glycosaminoglycans (GAGs) and ratio of collagen II/I. Finally, TGF-β1, GDF-5, and BMP-2 stimulation yielded mechanically robust cartilage rich in collagen II and GAGs in both cell types, following 4 weeks maturation. This study illustrates notable success in using the self-assembling method to generate robust, scaffold-free neocartilage constructs using expanded hACs and hMSCs. Stem Cells  2015;33:762–773
Single fetal demise in monochorionic pregnancies: incidence and patterns of cerebral injury
Authors: van Klink J. M. M. , van Steenis A. , Steggerda S. J. , Genova L. , Sueters M. , Oepkes D. , Lopriore E.
Published: November 2014

ABSTRACT

Objective

To evaluate the incidence, type and severity of cerebral injury in the surviving monochorionic (MC) cotwin after single fetal demise in twin pregnancies.

Methods

All MC pregnancies with single fetal demise that were evaluated at the Leiden University Medical Center between 2002 and 2013 were included. Perinatal characteristics, neonatal outcome and the presence of cerebral injury, observed on neuroimaging, were recorded for all cotwin survivors.

Results

A total of 49 MC pregnancies with single fetal demise, including one MC triplet, were included in the study (n = 50 cotwins). Median gestational age at occurrence of single fetal demise was 25 weeks and median interval between single fetal demise and live birth was 61 days, with a median gestational age at birth of 36 weeks. Severe cerebral injury was diagnosed in 13 (26%) of the 50 cotwins and was detected antenatally in 4/50 (8%) and postnatally in 9/50 (18%) cases. Cerebral injury was mostly due to hypoxic‐ischemic injury resulting in cystic periventricular leukomalacia, middle cerebral artery infarction or injury to basal ganglia, thalamus and/or cortex. Risk factors associated with severe cerebral injury were advanced gestational age at the occurrence of single fetal demise (odds ratio (OR), 1.14 (95% CI, 1.01–1.29) for each week of gestation; P = 0.03), twin–twin transfusion syndrome developing prior to single fetal demise (OR, 5.0 (95% CI, 1.30–19.13); P = 0.02) and a lower gestational age at birth (OR, 0.83 (95% CI, 0.69–0.99) for each week of gestation; P = 0.04).

Conclusions

Single fetal demise in MC pregnancies is associated with severe cerebral injury occurring in 1 in 4 surviving cotwins. Routine antenatal and postnatal neuroimaging, followed by standardized long‐term follow‐up, is mandatory. Copyright © 2014 ISUOG. Published by John Wiley & Sons Ltd.
Performance analysis of switch‐and‐stay combining in two‐way relay systems with analog network coding and time‐division broadcast protocols
Authors: Lei Xianfu , Hu Rose Qingyang , Fan Lisheng , Fan Pingzhi , Duong Trung Q.
Published: November 2014

In this paper, we consider switch‐and‐stay combining (SSC) in two‐way relay systems with two amplify‐and‐forward relays, one of which is activated to assist the information exchange between the two sources. The system operates in either analog network coding (ANC) protocol where the communication is only achieved with the help of the active relay or time‐division broadcast (TDBC) protocol where the direct link between two sources can be utilized to exploit more diversity gain. In both cases, we study the outage probability and bit error rate (BER) for Rayleigh fading channels. In particular, we derive closed‐form lower bounds for the outage probability and the average BER, which remain tight for different fading conditions. We also present asymptotic analysis for both the outage probability and the average BER at high signal‐to‐noise ratio. It is shown that SSC can achieve the full diversity order in two‐way relay systems for both ANC and TDBC protocols with proper switching thresholds. Copyright © 2014 John Wiley & Sons, Ltd.
Nanomedical engineering: shaping future nanomedicines
Authors: Luo Dandan , Carter Kevin A. , Lovell Jonathan F.
Published: November 2014

Preclinical research in the field of nanomedicine continues to produce a steady stream of new nanoparticles with unique capabilities and complex properties. With improvements come promising treatments for diseases, with the ultimate goal of clinical translation and better patient outcomes compared with current standards of care. Here, we outline engineering considerations for nanomedicines, with respect to design criteria, targeting, and stimuli‐triggered drug release strategies. General properties, clinical relevance, and current research advances of various nanomedicines are discussed in light of how these will realize their potential and shape the future of the field. WIREs Nanomed Nanobiotechnol 2015, 7:169–188. doi: 10.1002/wnan.1315

This article is categorized under:

Therapeutic Approaches and Drug Discovery > Emerging Technologies

Diagnostic Tools > In Vitro Nanoparticle-Based Sensing

Diagnostic Tools > In Vivo Nanodiagnostics and Imaging