bluuebunny/crossref_metadata_2025 huggingface dataset:
A fast, parameterized model of upper atmospheric ionization rates, chemistry, and conductivity
Authors: McGranaghan Ryan , Knipp Delores J. , Solomon Stanley C. , Fang Xiaohua
Published: May 2015

Rapid specification of ionization rates and ion densities in the upper atmosphere is essential when many evaluations of the atmospheric state must be performed, as in global studies or analyses of on‐orbit satellite data. Though many models of the upper atmosphere perform the necessary specification, none provide the flexibility of computational efficiency, high accuracy, and complete specification. We introduce a parameterized, updated, and extended version of the GLobal AirglOW (GLOW) model, called GLOWfast, that significantly reduces computation time and provides comparable accuracy in upper atmospheric ionization, densities, and conductivity. We extend GLOW capabilities by (1) implementing the nitric oxide empirical model, (2) providing a new model component to calculate height‐dependent conductivity profiles from first principles for the 80–200 km region, and (3) reducing computation time. The computational improvement is achieved by replacing the full, two‐stream electron transport algorithm with two parameterizations: (1) photoionization (QRJ from Solomon and Qian ()) and (2) electron impact ionization (F0810 from Fang et al. (, )). We find that GLOWfast accurately reproduces ionization rates, ion and electron densities, and Pedersen and Hall conductivities independent of the background atmospheric state and input solar and auroral activity. Our results suggest that GLOWfast may be even more appropriate for low characteristic energy auroral conditions. We demonstrate in a suite of 3028 case studies that GLOWfast can be used to rapidly calculate the ionization of the upper atmosphere with few limitations on background and input conditions. We support these results through comparisons with electron density profiles from COSMIC.
Type I Clathrates as Novel Silicon Anodes: An Electrochemical and Structural Investigation
Authors: Li Ying , Raghavan Rahul , Wagner Nicholas A. , Davidowski Stephen K. , Baggetto Loïc , Zhao Ran , Cheng Qian , Yarger Jeffery L. , Veith Gabriel M. , Ellis‐Terrell Carol , Miller Michael A. , Chan Kwai S. , Chan Candace K.
Published: May 2015

Silicon clathrates contain cage‐like structures that can encapsulate various guest atoms or molecules. An electrochemical evaluation of type I silicon clathrates based on Ba8AlySi46−y as the anode material for lithium‐ion batteries is presented here. Postcycling characterization with nuclear magnetic resonance and X‐ray diffraction shows no discernible structural or volume changes even after electrochemical insertion of 44 Li (≈1 Li/Si) into the clathrate structure. The observed properties are in stark contrast with lithiation of other silicon anodes, which become amorphous and suffer from large volume changes. The electrochemical reactions are proposed to occur as single phase reactions at approximately 0.2 and 0.4 V versus Li/Li+ during lithiation and delithiation, respectively, distinct from diamond cubic or amorphous silicon anodes. Reversible capacities as high as 499 mAh g−1 at a 5 mA g−1 rate were observed for silicon clathrate with composition Ba8Al8.54Si37.46, corresponding to ≈1.18 Li/Si. These results show that silicon clathrates could be promising durable anodes for lithium‐ion batteries.
An increased prevalence of thyroid disease in children with 22q11.2 deletion syndrome
Authors: Shugar Andrea L. , Shapiro Jessica M. , Cytrynbaum Cheryl , Hedges Stephanie , Weksberg Rosanna , Fishman Leona
Published: May 2015

We reviewed the health records of pediatric patients with 22q11.2 deletion syndrome (22q11.2 DS) seen over a 5‐year period in our 22q11.2 DS multidisciplinary clinic. We determined the prevalence of thyroid dysfunction in this population, in comparison to general population data. Statistical tests were applied to investigate trends in gender differences, thyroid disease subtype and co‐morbid conditions in the patients identified with thyroid disease. Of 169 subjects (92 male, 77 female) 9.5% had overt thyroid disease; of these, 1.8% had hyperthyroidism and 7.7% had hypothyroidism; 42% of patients with subclinical or prodromal thyroid disease progressed to overt disease. Our data indicate that thyroid disease prevalence in the 22q11DS pediatric population is significantly higher than that in the general pediatric population Furthermore, over 1/3 of patients in our study population who presented with subclinical thyroid disease progressed to overt disease, requiring medical therapy. Thyroid disease screening should be incorporated into routine medical management of children with 22q11.2 DS. Guidelines for screening individuals with 22q11.2 DS are presented. © 2015 Wiley Periodicals, Inc.
Risk factors for Dandy–Walker malformation: A population‐based assessment
Authors: Reeder Matthew R. , Botto Lorenzo D. , Keppler‐Noreuil Kim M. , Carey John C. , Byrne Janice L. B. , Feldkamp Marcia L. ,   the National Birth Defects Prevention Study
Published: May 2015

Dandy–Walker malformation (DWM) is the most common congenital malformation of the cerebellum, but its causes are largely unknown. An increasing number of genes associated with congenital cerebellar malformations have been identified; however, few studies have examined the potential role of non‐genetic, potentially modifiable risk factors. From the National Birth Defects Prevention Study, we examined maternal, paternal, and infant characteristics and maternal conditions and periconceptional exposures (from 1 month before to 3 months after conception) among infants with DWM (n = 160) and unaffected controls (n = 10,200), delivered between 1997 and 2009. Odds ratios, crude (cOR) and adjusted (aOR) were computed using logistic regression. Maternal factors associated with DWM included non‐Hispanic black race/ethnicity (aOR = 2.0, 95%CI: 1.3–3.2). Among maternal conditions, a history of infertility increased the risk for DWM (all: aOR = 2.4, 95%CI: 1.3–4.6; multiple: aOR = 3.9, 95%CI: 1.7–8.9). The lack of association with many maternal exposures supports the hypothesis of a major contribution of genetic factors to the risk for DWM; however, the observed associations with maternal non‐Hispanic black race/ethnicity and maternal history of infertility indicate that further research into factors underlying these characteristics may uncover potentially modifiable risk factors, acting alone or as a component of gene–environment interactions. © 2015 Wiley Periodicals, Inc.
10 years later: Assessing the impact of public health efforts on the collection of family health history
Authors: Welch Brandon M. , O'Connell Nathaniel , Schiffman Joshua D.
Published: May 2015

In 2004, a nationwide survey found that the majority (96.3%) of Americans believed their family health history (FHx) was important for their own health; however, only a third (29.8%) of respondents had ever actively collected this information. Over the past decade, government agencies, advocacy groups, professional societies, and healthcare provider organizations have aimed to improve the collection rates and utilization of FHx. This study assesses the current attitudes, knowledge, and practices of Americans regarding their FHx and whether the interventions over the past 10 years have led to any FHx‐related changes. We conducted a nationwide survey of 5,258 respondents using the same measures used in the 2004 survey. Overall, there was little change in Americans knowledge and use of FHx information. While there was a statistically significant increase in respondents who have actively collected their FHx (36.9%), respondents know roughly the same or less about his or her FHx today. Furthermore, only a small fraction (2.6%) had ever collected their FHx using a web‐based FHx tool. Several factors were identified which influence whether an individual actively collects his or her FHx. New FHx tools and approaches may be necessary to promote clinically meaningful improvement in FHx collection among patients. © 2015 Wiley Periodicals, Inc.
Concise and Practical Asymmetric Synthesis of a Challenging Atropisomeric HIV Integrase Inhibitor
Authors: Fandrick Keith R. , Li Wenjie , Zhang Yongda , Tang Wenjun , Gao Joe , Rodriguez Sonia , Patel Nitinchandra D. , Reeves Diana C. , Wu Jiang‐Ping , Sanyal Sanjit , Gonnella Nina , Qu Bo , Haddad Nizar , Lorenz Jon C. , Sidhu Kanwar , Wang June , Ma Shengli , Grinberg Nelu , Lee Heewon , Tsantrizos Youla , Poupart Marc‐André , Busacca Carl A. , Yee Nathan K. , Lu Bruce Z. , Senanayake Chris H.
Published: May 2015

A practical and efficient synthesis of a complex chiral atropisomeric HIV integrase inhibitor has been accomplished. The combination of a copper‐catalyzed acylation along with the implementation of the BI‐DIME ligands for a ligand‐controlled Suzuki cross‐coupling and an unprecedented bis(trifluoromethane)sulfonamide‐catalyzed tert‐butylation renders the synthesis of this complex molecule robust, safe, and economical. Furthermore, the overall synthesis was conducted in an asymmetric and diastereoselective fashion with respect to the imbedded atropisomer.
Thermally reversible highly cross‐linked polymeric materials based on furan/maleimide Diels‐Alder adducts
Authors: Mineo Placido , Barbera Vincenzina , Romeo Giovanni , Ghezzo Fabrizia , Scamporrino Emilio , Spitaleri Fabiola , Chiacchio Ugo
Published: May 2015

A novel thermally reversible cross‐linked polymer has been synthesized by a Diels‐Alder (DA) reaction between bis(4‐maleimido‐phenyl)fluorene (cBMI) and tetrakis‐furan monomers (4F) under microwave (MW) irradiation. The ultimate aim of this work was the preparation of a thermosetting material recyclable by a simple thermal treatment. The use of the MW irradiation was necessary because under thermal conditions the DA polymerization could lead to materials only partially cross‐linked for a not desired equilibrium between DA and retro‐DA processes induced by the high temperature. The easy thermal degradation of this cross‐linked material was ascertained by appropriate experiments. Moreover, to better study the involved reactions of formation and decomposition, a more simple model‐compound was also synthesized. The reported data confirm the recyclability of the synthesized cross‐linked polymer by simply heating with the possibility of a regeneration of the polymer network by a further MW irradiation. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42314.
Crystallization behavior and water vapor permeability of poly(lactic acid) nanocomposite under oscillatory shear
Authors: Xu Zhongbin , Su Liangyao , Jiang Shichao , Gu Wei , Peng Mao , Wang Pengfei
Published: May 2015

The crystallization behavior and water vapor permeability of a poly(lactic acid) (PLA) nanocomposite containing 5 wt % organic montmorillonite (OMMT) under oscillatory shear were investigated. Under the oscillatory shear, OMMT platelets exhibited a better intercalated structure and oriented along the flow direction, some of the OMMT platelets are exfoliated and dispersed in the form of single or few‐layer platelets. These well‐dispersed OMMT platelets acted as more effective nucleating and accelerating agent for the crystallization of PLA, as a result, the cold crystallization enthalpy was significantly decreased, the cold crystallization temperature was much closer to the melting temperature and the crystallinity is dramatically increased, which are observed for the first time. Moreover, the water vapor permeability is decreased by 36% due to the barrier effect of the well‐dispersed OMMT and the increased crystallinity of PLA, which increase the tortuous path that water molecules required to permeate. The mechanical properties are also enhanced owing to the well‐dispersed OMMT and increased crystallinity. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42321.
Compatibility improvement of poly(lactic acid)/thermoplastic polyurethane blends with 3‐aminopropyl triethoxysilane
Authors: Lai Sun‐Mou , Lan Yu‐Chi , Wu Wan‐Ling , Wang Yu‐Jhen
Published: May 2015

Poly(lactic acid) (PLA)/thermoplastic polyurethane (TPU) blends were prepared via a melt‐blending process with or without the addition of a 3‐aminopropyl triethoxysilane (APTES) compatibilizer at different dosages. The addition of the compatibilizer showed improved compatibility between TPU and PLA; this led to an enhanced dispersion of TPU within the PLA matrix. With the addition of 1‐phr APTES, the crystallization behavior did not vary much, but this exacerbated the formation of a second melting temperature for PLA at higher temperature. However, the addition of 5‐phr APTES into the PLA/TPU blends depressed the crystallization temperature and resulted in a melting temperature depression phenomena with the disappearance of the second melting peak because of the lubricated effect of low‐molecular‐weight species of APTES. The addition of a low dosage of APTES improved the impact strength further from 29.2 ± 1.4 to 40.7 ± 2.7 J/m but with a limited improvement in the tensile properties; this indicated that a higher dispersion of the dispersed phase did not always improve all of the mechanical properties because of the low‐molecular‐weight nature of the compatibilizer used. The physical properties of the added modifier needed to be considered as well. A low dosage of APTES (1 phr) also increased the viscosity because of the improved interaction between TPU and PLA at all of the investigated shear rate regions, but a higher dosage of compatibilizer induced another plasticizing effect to reduce the viscosity. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42322.
High glass transition temperature polyester coatings for the protection of stones
Authors: Pedna Andrea , Rosi Luca , Frediani Marco , Frediani Piero
Published: May 2015

Copolymers of lactic acid with mandelic or salicylic acid were synthetized through ring‐opening polymerization (ROP) and tested as protective coatings for stones. Most notably, glass transition temperature (Tg), hydrophobicity, and UV barrier properties were increased, making these materials more suitable as protective coating for outdoor stones than poly(lactic acid). A Tg of 76°C was obtained for the alternating copolymer lactic acid/mandelic acid and it was considerably higher than the one of poly(lactic acid) with similar molecular weight (50–55°C). Furthermore, the introduction of a perfluorinated moiety as chain‐end group, using a perfluoro alcohol as initiator of the ROP process, allowed to increase the hydrophobicity and stability of the new coatings. These polymers showed a good protective efficiency when applied on marble stones and preliminary stability tests under solar light showed low degradation, good stability to photo‐oxidative conditions, and negligible color changes after an aging time of 1000 h. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42323.
Thermal, mechanical, and structural properties of zno/polyethylene membranes made by thermally induced phase separation method
Authors: Jafarzadeh Yoones , Yegani Reza
Published: May 2015

In this study, ZnO/polyethylene membranes were fabricated via thermally induced phase separation method. A set of tests including FE‐SEM, EDX, XRD, DSC, TGA, DMA, mechanical test, and pure water flux (PWF) for characterization of membranes were carried out. The results of EDX, XRD, and TGA analyses confirmed the presence of ZnO nanoparticles in the polymer matrix. The results of DSC analysis revealed that the melting point as well as the crystallinity of the membranes increased slightly with increasing ZnO content. However, glass transition temperature of the membranes was not affected by presence of the particles. Addition of nanoparticles also increased storage modulus, loss modulus. and tensile at break of the membranes due to the stiffness improvement effect of inorganic ZnO. Finally, it was observed that incorporation of the nanoparticles improved PWF of the membranes, whereas humic acid rejection decreased due to the increase in mean pore radius of membranes. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42338.
Preparation and property of waterborne UV‐curable chain‐extended polyurethane surface sizing agent: Strengthening and waterproofing mechanism for cellulose fiber paper
Authors: Wang Haihua , Fan Jie , Fei Guiqiang , Lan Jing , Zhao Zhixin
Published: May 2015

Waterborne UV‐curable polyurethane (UWPU) dispersions with different hydrophilicity and functionalities were prepared by varying the content of dimethylol butanoic acid (DMBA) and pentaerythritol triacrylate (PETA). And linear and cyclic chain extenders with different functionalities were also incorporated into the UWPU backbone, including isophorone diamine (IPDA), diethylene triamine (DETA), and ethylene diamine (EDA). Effects of DMBA content, PETA content, photoinitiator content, UV curing time, chain extender on the properties of UWPU dispersions and films, as well as the properties of the unsized and sized paper were investigated. The water resistance and mechanical properties of sized paper were greatly relied on the particle size, the molecular weight, the croslinking density, and penetrability of UWPU. UWPU dispersion chain extended with IPDA (IPDA‐UWPU) displayed smaller particle size than that of UWPU. The paper sized with IPDA‐UWPU was endowed with best water resistance, tensile strength, folding strength and surface strength. XPS depth analysis revealed that IPDA‐UWPU exhibited better penetrability into the paper substrate than UWPU. SEM and AFM demonstrated that the smoothness of sized paper was improved, and the bond strength between fibers was enhanced. The obtained UWPU could be directly used as an effective and fast drying surface sizing agent for cellulose fiber paper. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42354.
Sentiment‐based event detection in Twitter
Authors: Paltoglou Georgios
Published: May 2015

The main focus of this article is to examine whether sentiment analysis can be successfully used for “event detection,” that is, detecting significant events that occur in the world. Most solutions to this problem are typically based on increases or spikes in frequency of terms in social media. In our case, we explore whether sudden changes in the positivity or negativity that keywords are typically associated with can be exploited for this purpose. A data set that contains several million Twitter messages over a 1‐month time span is presented and experimental results demonstrate that sentiment analysis can be successfully utilized for this purpose. Further experiments study the sensitivity of both frequency‐ or sentiment‐based solutions to a number of parameters. Concretely, we show that the number of tweets that are used for event detection is an important factor, while the number of days used to extract token frequency or sentiment averages is not. Lastly, we present results focusing on detecting local events and conclude that all approaches are dependant on the level of coverage that such events receive in social media.
Genetic algorithms andGaussianBayesian networks to uncover the predictive core set of bibliometric indices
Authors: Ibáñez Alfonso , Armañanzas Rubén , Bielza Concha , Larrañaga Pedro
Published: May 2015

The diversity of bibliometric indices today poses the challenge of exploiting the relationships among them. Our research uncovers the best core set of relevant indices for predicting other bibliometric indices. An added difficulty is to select the role of each variable, that is, which bibliometric indices are predictive variables and which are response variables. This results in a novel multioutput regression problem where the role of each variable (predictor or response) is unknown beforehand. We useGaussianBayesian networks to solve the this problem and discover multivariate relationships among bibliometric indices. These networks are learnt by a genetic algorithm that looks for the optimal models that best predict bibliometric data. Results show that the optimal inducedGaussianBayesian networks corroborate previous relationships between several indices, but also suggest new, previously unreported interactions. An extended analysis of the best model illustrates that a set of 12 bibliometric indices can be accurately predicted using only a smaller predictive core subset composed of citations, g‐index, q2‐index, and hr‐index. This research is performed using bibliometric data onSpanish full professors associated with the computer science area.
Dietary restriction decreases coenzyme Q and ubiquinol potentially via changes in gene expression in the model organism C. elegans
Authors: Fischer Alexandra , Klapper Maja , Onur Simone , Menke Thomas , Niklowitz Petra , Döring Frank
Published: May 2015

Dietary restriction (DR) is a robust intervention that extends both health span and life span in many organisms. Ubiquinol and ubiquinone represent the reduced and oxidized forms of coenzyme Q (CoQ). CoQ plays a central role in energy metabolism and functions in several cellular processes including gene expression. Here we used the model organism Caenorhabditis elegans to determine level and redox state of CoQ and expression of genes in response to DR. We found that DR down‐regulates the steady‐state expression levels of several evolutionary conserved genes (i.e. coq‐1) that encode key enzymes of the mevalonate and CoQ‐synthesizing pathways. In line with this, DR decreases the levels of total CoQ and ubiquinol. This CoQ‐reducing effect of DR is obvious in adult worms but not in L4 larvae and is also evident in the eat‐2 mutant, a genetic model of DR. In conclusion, we propose that DR reduces the level of CoQ and ubiquinol via gene expression in the model organism C. elegans. © 2015 BioFactors, 41(3):166–174, 2015
Toll‐like receptor 4 signaling inhibits malignant pleural effusion by altering Th1/Th17 responses
Authors: Xu Qian‐Qian , Zhou Qiong , Xu Li‐Li , Lin Hua , Wang Xiao‐Juan , Ma Wan‐Li , Zhai Kan , Tong Zhao‐Hui , Su Yunchao , Shi Huan‐Zhong
Published: May 2015

Toll‐like receptor 4 (TLR4) is involved in multiple malignancies; however, the role of TLR4 in the pathogenesis of malignant pleural effusion (MPE) remains unknown. The objectives of this study were to explore the impact of TLR4 signaling on the development of MPE in a murine model and to define the underline mechanisms by which TLR works. Development of MPE as well as proliferation and angiogenesis of pleural tumor were determined in TLR4–/– and wild type mice. Differentiation of Th1 and Th17 cells as well as their signal transductions was explored. The effects of TLR4 signaling on survival of mice bearing MPE were also investigated. Compared with wild type mice, Th1 cells were augmented, and Th17 cells were suppressed in MPE from TLR4–/– mice. The in vitro experiments showed that TLR4 deficiency promoted Th1 cell differentiation via enhancing STAT1 pathway and inhibited Th17 cell differentiation via suppressing STAT3 pathway. TLR4 deficiency promoted MPE formation and, thus, accelerated the death of mice bearing MPE, whereas intraperitoneal injection of anti‐IFN‐γ mAb or recombinant mouse IL‐17 protein into TLR4–/– mice was associated with improved survival. Our data provides the first definitive evidence of a role for TLR4 signaling in protective immunity in the development of MPE. Our findings also demonstrate that TLR4 deficiency promotes MPE formation and accelerates mouse death by enhancing Th1 and suppressing Th17 response.
An extended evolutionary design method for the optimization of hydrogen networks with pressure constraint
Authors: Jia Xuexue , Li Li , Liu Guilian , Yang Minbo , Liu Yongbiao
Published: May 2015

In this work, the evolutionary method is extended to the work utility consumption and the capital cost of compressors incorporated with fresh hydrogen consumption in the optimization of hydrogen networks. The total cost matrix (TC matrix) is constructed with the cost of each possible match calculated. Further, the minimum total cost rule is proposed to compare different sources that can match the same sink. Based on this, the potential match matrix (P matrix) and the optimal match matrix (O matrix) can be determined sequentially. The fresh hydrogen, work utility consumption, total cost, and corresponding hydrogen distribution network can be obtained from the O matrix. The hydrogen network of a real refinery is studied to demonstrate the application of the extended evolutionary method. The results show that total cost determined by the extended method is 3.32 % less than that identified by the original evolutionary method, and the same as that calculated by the mathematical programming method.
An integrated method for preparing low quinoline insoluble modified pitch
Authors: Liu Peng , Zhang Dexiang , Yang Xu , Cheng Bowu
Published: May 2015

Pitches with three different softening points (SPs) were obtained from the same original coal tar purified in the laboratory by centrifuge, hot filtration, and distillation. The effect of temperature and residence time on thermal polymerization of the three types of pitch was investigated using a laboratory autoclave. The differences in the composition of the three types of pitch was established by elemental and thermogravimetric analyses. The results show that the purified coal tar with low quinoline insolubles (QI) of 1.8 g/kg (0.18 wt%) was obtained by centrifuge and hot filtration treatment at 348 K, with a 1000‐mesh filter. The coal tar recovery is approximately 800 g/kg (80 wt%). The rate of thermal polymerization is influenced by the SP of the original pitch controlled by the distillation conditions. The QI of the modified pitch decreases (from 3.5 to 1.8 g/kg, 0.35 to 0.18 wt%) in the initial reaction stages at low temperatures (below 683 K) and increases at higher temperatures during the thermal treatment. The SP, coking value (CV), and toluene insolubles (TI) of modified pitches increase monotonically with temperature. A modified pitch with a low QI of 1.8 g/kg (0.18 wt%), a SP of 366 K, a TI of 234.2 g/kg (23.42 wt%), and a CV of 485 g/kg (48.50 wt%) was prepared from the original pitch with an SP of 319 K by thermal polymerization at 683 K for 1 h.
Landscape characteristics influencing the genetic structure of greater sage‐grouse within the stronghold of their range: a holistic modeling approach
Authors: Row Jeffrey R. , Oyler‐McCance Sara J. , Fike Jennifer A. , O'Donnell Michael S. , Doherty Kevin E. , Aldridge Cameron L. , Bowen Zachary H. , Fedy Bradley C.
Published: May 2015

Given the significance of animal dispersal to population dynamics and geographic variability, understanding how dispersal is impacted by landscape patterns has major ecological and conservation importance. Speaking to the importance of dispersal, the use of linear mixed models to compare genetic differentiation with pairwise resistance derived from landscape resistance surfaces has presented new opportunities to disentangle the menagerie of factors behind effective dispersal across a given landscape. Here, we combine these approaches with novel resistance surface parameterization to determine how the distribution of high‐ and low‐quality seasonal habitat and individual landscape components shape patterns of gene flow for the greater sage‐grouse (Centrocercus urophasianus) across Wyoming. We found that pairwise resistance derived from the distribution of low‐quality nesting and winter, but not summer, seasonal habitat had the strongest correlation with genetic differentiation. Although the patterns were not as strong as with habitat distribution, multivariate models with sagebrush cover and landscape ruggedness or forest cover and ruggedness similarly had a much stronger fit with genetic differentiation than an undifferentiated landscape. In most cases, landscape resistance surfaces transformed with 17.33‐km‐diameter moving windows were preferred, suggesting small‐scale differences in habitat were unimportant at this large spatial extent. Despite the emergence of these overall patterns, there were differences in the selection of top models depending on the model selection criteria, suggesting research into the most appropriate criteria for landscape genetics is required. Overall, our results highlight the importance of differences in seasonal habitat preferences to patterns of gene flow and suggest the combination of habitat suitability modeling and linear mixed models with our resistance parameterization is a powerful approach to discerning the effects of landscape on gene flow.
Linking mechanistic toxicology to population models in forecasting recovery from chemical stress: A case study from Jackfish Bay, Ontario, Canada
Authors: Miller David H. , Tietge Joseph E. , McMaster Mark E. , Munkittrick Kelly R. , Xia Xiangsheng , Griesmer David A. , Ankley Gerald T.
Published: May 2015

Recovery of fish and wildlife populations after stressor mitigation serves as a basis for evaluating remediation success. Unfortunately, effectively monitoring population status on a routine basis can be difficult and costly. In the present study, the authors describe a framework that can be applied in conjunction with field monitoring efforts (e.g., through effects-based monitoring programs) to link chemically induced alterations in molecular and biochemical endpoints to adverse outcomes in whole organisms and populations. The approach employs a simple density-dependent logistic matrix model linked to adverse outcome pathways (AOPs) for reproductive effects in fish. Application of this framework requires a life table for the organism of interest, a measure of carrying capacity for the population of interest, and estimation of the effect of stressors on vital rates of organisms within the study population. The authors demonstrate the framework using linked AOPs and population models parameterized with long-term monitoring data for white sucker (Catostomus commersoni) collected from a study site at Jackfish Bay, Lake Superior, Canada. Individual responses of fish exposed to pulp mill effluent were used to demonstrate the framework's capability to project alterations in population status, both in terms of ongoing impact and subsequent recovery after stressor mitigation associated with process changes at the mill. The general approach demonstrated at the Jackfish Bay site can be applied to characterize population statuses of other species at a variety of impacted sites and can account for effects of multiple stressors (both chemical and nonchemical) and dynamics within complex landscapes (i.e., meta-populations including emigration and immigration processes). Environ Toxicol Chem 2015;34:1623–1633. © 2015 SETAC
Tracking multiple modes of endocrine activity in Australia's largest inland sewage treatment plant and effluent- receiving environment using a panel of in vitro bioassays
Authors: Roberts Jenna , Bain Peter A. , Kumar Anupama , Hepplewhite Christopher , Ellis David J. , Christy Andrew G. , Beavis Sara G.
Published: May 2015

Estrogenicity of sewage effluents, and related ecotoxicological effects in effluent-receiving environments, have been widely reported over the last 2 decades. However, relatively little attention has been given to other endocrine pathways that may be similarly disrupted by a growing list of contaminants of concern. Furthermore, the Australian evidence base is limited compared with those of Europe and North America. During a low dilution period in summer, the authors investigated multiple endocrine potencies in Australia's largest inland sewage treatment plant (STP) and the Lower Molonglo/Upper Murrumbidgee effluent-receiving environment. This STP receives 900 L/s of mostly domestic wastewater from a population of 350 000, and contributes a high proportion of total flow in the lower catchment during dry periods. A panel of in vitro receptor-driven transactivation assays were used to detect (anti)estrogenic, (anti) androgenic, (anti)progestagenic, glucocorticoid, and peroxisome-proliferator activity at various stages of the sewage treatment process. Total estrogenic and (anti)androgenic potency was removed after primary and/or secondary treatment; however, total removal efficiency for glucocorticoid potency was poorer (53–66%), and progestagenic potency was found to increase along the treatment train. Estrogenicity was detected in surface waters and bed sediments upstream and downstream of the effluent outfall, at maximum levels 10 times lower than low-hazard thresholds. Glucocorticoid and progestagenic activity were found to persist to 4 km downstream of the effluent outfall, suggesting that future research is needed on these endocrine-disrupting chemical categories in effluent-receiving systems. Environ Toxicol Chem 2015;34:2271–2281. © 2015 SETAC
Adverse Outcome Pathways can drive non‐animal approaches for safety assessment
Authors: Burden Natalie , Sewell Fiona , Andersen Melvin E. , Boobis Alan , Chipman J. Kevin , Cronin Mark T. D. , Hutchinson Thomas H. , Kimber Ian , Whelan Maurice
Published: May 2015

Adverse Outcome Pathways (AOPs) provide an opportunity to develop new and more accurate safety assessment processes for drugs and other chemicals, and may ultimately play an important role in regulatory decision making. Not only can the development and application of AOPs pave the way for the development of improved evidence‐based approaches for hazard and risk assessment, there is also the promise of a significant impact on animal welfare, with a reduced reliance on animal‐based methods. The establishment of a useable and coherent knowledge framework under which AOPs will be developed and applied has been a first critical step towards realizing this opportunity. This article explores how the development of AOPs under this framework, and their application in practice, could benefit the science and practice of safety assessment, while in parallel stimulating a move away from traditional methods towards an increased acceptance of non‐animal approaches. We discuss here the key areas where current, and future initiatives should be focused to enable the translation of AOPs into routine chemical safety assessment, and lasting 3Rs benefits. © 2015 The Authors. Journal of Applied Toxicology published by John Wiley & Sons Ltd.
A quantitative approach for studying the bioactivity of nanohydroxyapatite/gold composites
Authors: Mostafa Amany A. , Oudadesse Hassane , El‐Sayed Mayyada M. H.
Published: May 2015

This work describes a quantitative kinetic approach to assess the in vitro bioactivity of gold‐doped hydroxyapatite‐polyvinyl alcohol nanocomposites. The surface morphology of the in situ prepared nanocomposites as characterized by transmission electron microscopy (TEM) revealed a rod‐like shape. Differential thermal analysis‐thermogravimetric (DTA–TG), and fourier transformed infrared spectroscopy (FTIR) as well as zeta potential measurements of the prepared nanocomposites were carried out. Uptake profiles of Ca and P were studied onto nanocomposites of different gold concentrations after their soaking in simulated body fluid and they best followed the pseudo second‐order kinetic model. The highest uptakes of both Ca and P were obtained using the nanocomposite with the lowest concentration of gold. Furthermore, sorption mechanism was described by the intraparticle diffusion model where pore diffusion was found to be the rate limiting step. The prepared nanocomposites have promising potential in orthopedic and tissue engineering applications because of their high capacity and fast uptake for Ca and P, which form apatite. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 3483–3492, 2015.
ATR‐FTIR measurements of albumin and fibrinogen adsorption: Inert versus calcium phosphate ceramics
Authors: Boix Marcel , Eslava Salvador , Costa Machado Gil , Gosselin Emmanuel , Ni Na , Saiz Eduardo , De Coninck Joël
Published: May 2015

Arthritis, bone fracture, bone tumors and other musculoskeletal diseases affect millions of people across the world. Nowadays, inert and bioactive ceramics are used as bone substitutes or for bone regeneration. Their bioactivity is very much dictated by the way proteins adsorb on their surface. In this work, we compared the adsorption of albumin and fibrinogen on inert and calcium phosphates ceramics (CaPs) using attenuated total reflection Fourier transform infrared spectroscopy (ATR‐FTIR) to follow in situ protein adsorption on these materials. To this effect, we developed a sol‐gel technique to control the surface chemistry of an ATR‐FTIR detector. Hydroxyapatite adsorbed more albumin and β‐tricalcium phosphate adsorbed more fibrinogen. Biphasic calcium phosphate presented the lowest adsorption among CaP for both proteins, illustrating the effect of surface heterogeneities. Inert ceramics adsorbed a lower amount of both proteins compared with bioactive ceramics. A significant change was observed in the conformation of the adsorbed protein versus the surface chemistry. Hydroxyapatite produced a larger loss of α‐helix structure on albumin and biphasic calcium phosphate reduced β‐sheet percentage on fibrinogen. Inert ceramics produced large α‐helix loss on albumin and presented weak interaction with fibrinogen. Zirconia did not adsorb albumin and titanium dioxide promoted huge denaturalization of fibrinogen. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 3493–3502, 2015.
Repetitive jumping and sprinting until exhaustion alters hamstring reflex responses and tibial translation in males and females
Authors: Behrens Martin , Mau‐Moeller Anett , Wassermann Franziska , Plewka Antje , Bader Rainer , Bruhn Sven
Published: May 2015

The incidence of anterior cruciate ligament injuries is considerably higher in females than in males and the underlying mechanisms are still under debate. Research indicates that the neuromuscular system of females and males might respond differently to the same fatigue protocol due to differences in muscle activation during movement tasks. This study analyzed sex differences in hamstring reflex responses and posterior‐anterior tibial translation (TT) before and after fatiguing exercise. We measured the isolated movement of the tibia relative to the femur as a consequence of mechanically induced TT in standing subjects as well as muscle activity of the hamstrings before and after repetitive jumping and sprinting until exhaustion. Muscle fatigue delayed reflex onset latencies in females and males. A reduction in reflex responses associated with an increased TT was observed after fatiguing exercise for both sexes. Data indicate that the used fatigue protocol altered the latency and magnitude of reflex responses as well as TT in females and males. Based on the results of previous research and the outcome of this study, it might be that sex‐specific effects of fatigue on reflex activity and mechanical stability of the knee depend on the kind of fatiguing exercise. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1687–1692, 2015.
Quantitative and functional pulsed arterial spin labeling in the human brain at 9.4 t
Authors: Bause Jonas , Ehses Philipp , Mirkes Christian , Shajan G. , Scheffler Klaus , Pohmann Rolf
Published: May 2015

Purpose

The feasibility of multislice pulsed arterial spin labeling (PASL) of the human brain at 9.4 T was investigated. To demonstrate the potential of arterial spin labeling (ASL) at this field strength, quantitative, functional, and high‐resolution (1.05 × 1.05 × 2 mm3) ASL experiments were performed.

Methods

PASL was implemented using a numerically optimized adiabatic inversion pulse and presaturation scheme. Quantitative measurements were performed at 3 T and 9.4 T and evaluated on a voxel‐by‐voxel basis. In a functional experiment, activation maps obtained with a conventional blood‐oxygen‐level‐dependent (BOLD)‐weighted sequence were compared with a functional ASL (fASL) measurement.

Results

Quantitative measurements revealed a 23% lower perfusion in gray matter and 17% lower perfusion in white matter at 9.4 T compared with 3 T. Furthermore almost identical transit delays and bolus durations were found at both field strengths whereas the calculated voxel volume corrected signal‐to‐noise ratio was 1.9 times higher at 9.4 T. This result was confirmed by the high‐resolution experiment. The functional experiment yielded comparable activation maps for the fASL and BOLD measurements.

Conclusion

Although PASL at ultrahigh field strengths is limited by high specific absorption rate, functional and quantitative perfusion‐weighted images showing a high degree of detail can be obtained. Magn Reson Med 75:1054–1063, 2016. © 2015 Wiley Periodicals, Inc.
Independent validation of four‐dimensional flow MR velocities and vortex ring volume using particle imaging velocimetry and planar laser‐Induced fluorescence
Authors: Töger Johannes , Bidhult Sebastian , Revstedt Johan , Carlsson Marcus , Arheden Håkan , Heiberg Einar
Published: May 2015

Purpose

This study aimed to: (i) present and characterize a phantom setup for validation of four‐dimensional (4D) flow using particle imaging velocimetry (PIV) and planar laser‐induced fluorescence (PLIF); (ii) validate 4D flow velocity measurements using PIV; and (iii) validate 4D flow vortex ring volume (VV) using PLIF.

Methods

A pulsatile pump and a tank with a 25‐mm nozzle were constructed. PIV measurements (1.5 × 1.5 mm pixels, temporal resolution 10 ms) were obtained on two occasions. The 4D flow (3 × 3 × 3 mm voxels, temporal resolution 50 ms) was acquired using SENSE = 2. VV was quantified using PLIF and 4D flow.

Results

PIV showed excellent day‐to‐day stability (R2 = 0.99, bias −0.04 ± 0.72 cm/s). The 4D flow mean velocities agreed well with PIV (R2 = 0.95, bias 0.16 ± 2.65 cm/s). Peak velocities in 4D flow were underestimated by 7–18% compared with PIV (y = 0.79x + 2.7, R2 = 0.96, −12 ± 5%). VV showed excellent agreement between PLIF and 4D flow (R2 = 0.99, 2.4 ± 1.5 mL).

Conclusion

This study shows: (i) The proposed phantom enables reliable validation of 4D flow. (ii) 4D flow velocities show good agreement with PIV, but peak velocities were underestimated due to low spatial and temporal resolution. (iii) Vortex ring volume (VV) can be quantified using 4D flow. Magn Reson Med 75:1064–1075, 2016. © 2015 Wiley Periodicals, Inc.
Demonstration of nonlinearity bias in the measurement of the apparent diffusion coefficient in multicenter trials
Authors: Malyarenko Dariya I. , Newitt David , J. Wilmes Lisa , Tudorica Alina , Helmer Karl G. , Arlinghaus Lori R. , Jacobs Michael A. , Jajamovich Guido , Taouli Bachir , Yankeelov Thomas E. , Huang Wei , Chenevert Thomas L.
Published: May 2015

Purpose

Characterize system‐specific bias across common magnetic resonance imaging (MRI) platforms for quantitative diffusion measurements in multicenter trials.

Methods

Diffusion weighted imaging (DWI) was performed on an ice‐water phantom along the superior–inferior (SI) and right–left (RL) orientations spanning ±150 mm. The same scanning protocol was implemented on 14 MRI systems at seven imaging centers. The bias was estimated as a deviation of measured from known apparent diffusion coefficient (ADC) along individual DWI directions. The relative contributions of gradient nonlinearity, shim errors, imaging gradients, and eddy currents were assessed independently. The observed bias errors were compared with numerical models.

Results

The measured systematic ADC errors scaled quadratically with offset from isocenter, and ranged between −55% (SI) and 25% (RL). Nonlinearity bias was dependent on system design and diffusion gradient direction. Consistent with numerical models, minor ADC errors (±5%) due to shim, imaging and eddy currents were mitigated by double echo DWI and image coregistration of individual gradient directions.

Conclusion

The analysis confirms gradient nonlinearity as a major source of spatial DW bias and variability in off‐center ADC measurements across MRI platforms, with minor contributions from shim, imaging gradients and eddy currents. The developed protocol enables empiric description of systematic bias in multicenter quantitative DWI studies. Magn Reson Med 75:1312–1323, 2016. © 2015 Wiley Periodicals, Inc.
Avoiding War in Tarapacá (Northern Chile) During the Andean Late Intermediate Period (AD 1000–1450)
Authors: Pacheco Aryel , Retamal Rodrigo
Published: May 2015

The Late Intermediate period (LIP, AD 1000–1450) in the South Central Andes is commonly characterized by an increase in violence. Here, we analyse evidence to test whether the population that inhabited the oasis of Pica (Region of Tarapacá, Northern Chile) during LIP was engaged in violent warfare. The analysis of 96 individuals showed a low prevalence of violence‐related injuries (N = 6/96). Facial traumas observed on females could be a result of domestic violence, whereas nasal traumas found in males could be interpreted as a result of ritualized combats. One male exhibits a point embedded in his first right rib which is the only injury that can be attributed to open intergroup combat. These findings, combined with the mortuary characteristics of the Pica 8 cemetery, the lack of defensive constructions at the site, the settlement pattern and the iconography, do not support the existence of war at Pica during the LIP. The weapons found at Pica 8 cemetery are elaborately decorated, and many are clearly useless in combat so they were likely not made to be used in open conflicts. In addition, clothes considered to belong to warriors may be alternately interpreted as garments used for ceremonial purpose. Taking into account the belligerent climate in contemporaneous San Pedro de Atacama, we suggest that the Pica population employed ritualized violence as a means of avoiding larger conflicts or war. We propose that male violence in controlled scenarios permitted the sublimation of social inequalities or internal conflicts, and could have been used in order to create and maintain social stability. Copyright © 2015 John Wiley & Sons, Ltd.
Preparation and thermal properties of polyethylene terephthalate/huntite–hydromagnesite composites
Authors: Baştürk Emre , Madakbaş Seyfullah , Karadoğan Betül , Vezir Kahraman Memet
Published: May 2015

In this report, it was aimed to the improve thermal stability of polyethylene terephthalate (PET) by adding huntite/hydromagnesite minerale. PET/huntite/hydromagnesite composites were prepared by adding various proportions of huntite/hydromagnesite to PET. The chemical structures of the composites were characterized by Fourier transform infrared spectroscopy (FTIR) and X‐ray diffraction (XRD) analysis. Thermal properties of the composites were determined by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Glass‐transition temperatures and char yields increased with the increase of the huntite/hydromagnesite content in the composites. The surface morphologies of the composites were investigated by a scanning electron microscopy. The obtained results proved that the composite system is more thermally stable than the pure PET itself. POLYM. COMPOS., 37:3275–3279, 2016. © 2015 Society of Plastics Engineers