bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimization of bioreactor operating conditions using computational fluid dynamics techniques
Authors: Koerich Daniela M. , Rosa Leonardo M.
Published: August 2016

High hydraulic retention times are commonly used in bioreactors, as they provide greater contact time between substrate and biomass. These reactors also operate at low flow rates to minimize damage to the biomass due to shear stress and drag. However, a high flow rate provides greater mixing, and thus the optimal operation condition is difficult to estimate. In this study, the effect of different flow rates on the behaviour of the phases in an anaerobic sequencing batch bioreactor is evaluated numerically. Fluent 15 code was used, considering the two‐phase, transient, and turbulent flow in a three‐dimensional mesh. The turbulence, the drag of the biomass flocs to the recirculation system, and the shear stress in the remaining solids were evaluated. For the reactor evaluated in this study, the flow rate of 189.4 g/s was found to be the most suitable, not only for the operation of the reactor, but also to provide energy savings in the operation of the recirculation pump.
Impact of salinity on warm water‐based mineable oil sands processing
Authors: Chen Tong , Lin Feng , Primkulov Bauyrzhan , He Lin , Xu Zhenghe
Published: August 2016

Continuous use of caustics and increased level of water recycling inevitably increase the salinity of process water, which is a growing challenge in the current warm water‐based bitumen extraction process. The current study aims at understanding how salinity of process water affects bitumen recovery from mineable oil sands ores. Laboratory flotation results showed an ore‐dependent effect of salinity on bitumen recovery and froth quality. Processing of low‐grade ores suffered a dramatic loss in bitumen recovery with increasing NaCl up to 4000 ppm (i.e. 1574 ppm Na+) at pH 8.5, while only a marginal effect of salinity was found on the processability of a high‐grade ore. The use of caustics as a conventional approach to increase bitumen recovery and froth quality of poor processing ores showed a more severe negative impact of salinity on the processability of low‐grade ores. Salt addition was found to be detrimental to bitumen liberation and bitumen‐bubble attachment in the presence of fines, more so at higher pH of processing water. Increasing salt concentration in solution led to a significant decrease in the magnitude of negative zeta potentials for both bitumen and fine solids. These findings provide scientific guidance to searching for remediation strategies other than using caustics. Such an approach studied was the blending of low‐grade ores with high‐grade ores to minimize the negative impact of increased salinity in recycle water on bitumen extraction.
Application of mass balance models in the process of ozone removal of naphthenic acids from water
Authors: Al jibouri Ali Kamel H. , Wu Jiangning , Upreti Simant Ranjan
Published: August 2016

The oil sands process‐affected water (OSPW), produced in large amounts during the extraction of crude oil from oil sands, is toxic mainly due to the presence of naphthenic acids (NAs), among other constituents. Ozonation is an effective method for the removal of NAs. To provide information for better control of NAs ozonation, models based on mass balance were developed in this study to predict the concentration profiles of commercial NAs, dissolved ozone, and gaseous ozone during the process. It was found that the developed models successfully predicted the concentrations of commercial NAs and gaseous ozone. For the dissolved ozone concentration, the developed model can predict the equilibrium concentrations well. However, the actual ozone consumption was higher than that predicted by the model at the initial period of the ozonation process. This deviation possibly resulted from the inapplicability of the gas‐liquid equilibrium conditions at the initial high rate stage of the reaction. In addition, the Henry's law constant and the overall mass transfer coefficient for the given system were determined experimentally. Also investigated in this study was the effects of inlet gaseous ozone concentration into the reactor on the removal of NAs and on the concentration of dissolved ozone. As expected, the increase in inlet ozone concentration enhanced the removal of NAs and increased the concentration of dissolved ozone.
Distinct migratory behaviors of striosome and matrix cells underlying the mosaic formation in the developing striatum
Authors: Hagimoto Kazuya , Takami Saki , Murakami Fujio , Tanabe Yasuto
Published: August 2016

The striatum, the largest nucleus of the basal ganglia controlling motor and cognitive functions, can be characterized by a labyrinthine mosaic organization of striosome/matrix compartments. It is unclear how striosome/matrix mosaic formation is spatially and temporally controlled at the cellular level during striatal development. Here, by combining in vivo electroporation and brain slice cultures, we set up a prospective experimental system in which we differentially labeled striosome and matrix cells from the time of birth and followed their distributions and migratory behaviors. Our results showed that, at an initial stage of striosome/matrix mosaic formation, striosome cells were mostly stationary, whereas matrix cells actively migrated in multiple directions regardless of the presence of striosome cells. The mostly stationary striosome cells were still able to associate to form patchy clusters via attractive interactions. Our results suggest that the restricted migratory capability of striosome cells may allow them to cluster together only when they happen to be located in close proximity to each other and are not separated by actively migrating matrix cells. The way in which the mutidirectionally migrating matrix cells intermingle with the mostly stationary striosome cells may therefore determine the topographic features of striosomes. At later stages, the actively migrating matrix cells began to repulse the patchy clusters of striosomes, presumably enhancing the striosome cluster formation and the segregation and eventual formation of dichotomous homogeneous striosome/matrix compartments. Overall, our study reveals temporally distinct migratory behaviors of striosome/matrix cells, which may underlie the sequential steps of mosaic formation in the developing striatum. J. Comp. Neurol. 525:794–817, 2017. © 2016 Wiley Periodicals, Inc.
Data assimilation for identification of cardiovascular network characteristics
Authors: Lal Rajnesh , Mohammadi Bijan , Nicoud Franck
Published: August 2016

A method to estimate the hemodynamics parameters of a network of vessels using an Ensemble Kalman filter is presented. The elastic moduli (Young's modulus) of blood vessels and the terminal boundary parameters are estimated as the solution of an inverse problem. Two synthetic test cases and a configuration where experimental data are available are presented. The sensitivity analysis confirms that the proposed method is quite robust even with a few numbers of observations. The simulations with the estimated parameters recovers target pressure or flow rate waveforms at given specific locations, improving the state‐of‐the‐art predictions available in the literature. This shows the effectiveness and efficiency of both the parameter estimation algorithm and the blood flow model.
Modeling of light propagation in the human neck for diagnoses of thyroid cancers by diffuse optical tomography
Authors: Fujii H. , Yamada Y. , Kobayashi K. , Watanabe M. , Hoshi Y.
Published: August 2016

Diffuse optical tomography using near‐infrared light in a wavelength range from 700 to 1000 nm has the potential to enable non‐invasive diagnoses of thyroid cancers; some of which are difficult to detect by conventional methods such as ultrasound tomography. Diffuse optical tomography needs to be based on a physically accurate model of light propagation in the neck, because it reconstructs tomographic images of the optical properties in the human neck by inverse analysis. Our objective here was to investigate the effects of three factors on light propagation in the neck using the 2D time‐dependent radiative transfer equation: (1) the presence of the trachea, (2) the refractive‐index mismatch at the trachea‐tissue interface, and (3) the effect of neck organs other than the trachea (spine, spinal cord, and blood vessels). There was a significant influence of reflection and refraction at the trachea‐tissue interface on the light intensities in the region between the trachea and the front of the neck surface. Organs other than the trachea showed little effect on the light intensities measured at the front of the neck surface although these organs affected the light intensities locally. These results indicated the necessity of modeling the refractive‐index mismatch at the trachea‐tissue interface and the possibility of modeling other neck organs simply as a homogeneous medium when the source and detectors were far from large blood vessels.
Facile Synthesis of NixZn1−xFe2O4 (x=0, 0.25, 0.5, 0.75, 1) as Anode Materials for Lithium Storage
Authors: Li Linlin , Jin Bo , Lang Xingyou , Yang Chuncheng , Gao Wang , Zhu Yongfu , Dou Shixue , Jiang Qing
Published: August 2016

NixZn1−xFe2O4 (x=0, 0.25, 0.5, 0.75, 1) compounds were prepared by a hydrothermal method and subsequent heat treatment. The physical characteristics of the samples were investigated by field‐emission SEM, XRD, X‐ray photoelectron spectroscopy, and TEM. The electrochemical properties of NixZn1−xFe2O4 (x=0, 0.25, 0.5, 0.75, 1) as anode materials were tested for lithium‐ion batteries. The lithium‐storage properties of the electrodes were assessed by cyclic voltammetry and galvanostatic cycling. Among the five samples, Ni0.25Zn0.75Fe2O4 shows good electrochemical performance with a discharge capacity of 1488 mAh g−1 in the initial cycle and 856 mAh g−1 after 100 cycles.
Using multiple tracers and directly accounting for trophic modification improves dietary mixing‐model performance
Authors: Brett M. T. , Eisenlord M. E. , Galloway A. W. E.
Published: August 2016

Stable isotope (SI) mixing models are one of the most common approaches used to infer resource pathways in consumers. However, SI‐based analyses are often underdetermined, and consumer SI fractionation is often unknown. The use of fatty acid (FA) biomarkers in mixing models offers an alternative approach that can resolve the underdetermined constraint. A limitation to both methods is the considerable uncertainty regarding the “trophic modification” of dietary tracers, which occurs when consumers transform dietary resources into their own tissues. We tested the utility of SI and FA approaches for inferring the diets of the marine benthic isopod (Idotea wosnesenskii) fed various marine macroalgae in controlled feeding trials. Our analyses quantified how the accuracy and precision of Bayesian mixing models were influenced by the choice of algorithm (SIAR vs. MixSIR), trophic modification (assumed or known), and whether the model was under or overdetermined (seven sources and two vs. 26 tracers) for cases where isopods were fed an exclusive diet of one of the seven macroalgae. Using the conventional approach (two SI with assumed trophic modification) resulted in average model outputs, that is, the contribution from the exclusive resource =0.20 ± 0.23 (0.00–0.79), mean ± SD (95% credible interval), that only differed slightly from the prior assumption. This result was only somewhat improved by the use of measured trophic modification values for SI data. Using the FA‐based approach with known trophic modification greatly improved model performance, that is, the contribution from the exclusive resource =0.91 ± 0.10 (0.58–0.99). The choice of algorithm (SIAR vs. MixSIR) made a clear difference when trophic modification was known, and the model was overdetermined. In this case, SIAR and MixSIR had outputs of 0.86 ± 0.11 (0.48–0.96) and 0.96 ± 0.05 (0.79–1.00), respectively. When using FA biomarkers, going from two to seven tracers dramatically improved model performance (i.e., from 0.55 to 0.89, respectively), whereas going from 13 to 26 tracers only improved performance by 0.01. This analysis shows the choice and number of dietary tracers and the trophic modification assumption greatly influence the performance of mixing‐model dietary reconstructions and ultimately our understanding of what resources actually support aquatic consumers.
Simultaneous production of 1,3‐propanediol and n‐butanol by Clostridium pasteurianum: In situ gas stripping and cellular metabolism
Authors: Groeger Christin , Sabra Wael , Zeng An‐Ping
Published: August 2016

Clostridium pasteurianum is a promising producer of the bulk chemicals 1,3‐propanediol and n‐butanol (BuOH), with significantly different product patterns and physiology from other typical Clostridia. Nevertheless, its growth and product formation are ultimately limited by the accumulation of inhibiting products, especially by BuOH. In this study, we implemented in situ gas stripping for BuOH removal and compared the stripping performance of external nitrogen (N2) and fermentation effluent gas (FG) from the process itself. Gas stripping was studied in fermentations of glycerol and a mixture of glycerol and glucose. In general, N2 exhibits favourable physical properties to strip out BuOH from an aqueous phase. However, in situ removal of butanol in C. pasteurianum culture with N2 stripping strongly perturbs the culture conditions such as the redox potential and thus the physiology of the microorganism, leading to enhanced formation of organic acids, especially in cosubstrate fermentation, whereas the use of FG does not show such perturbations. In an effort to explore the use of FG for gas stripping the effects of FG circulation rate and stirring speed of the bioreactor on BuOH stripping efficiency and the fermentation performance were studied in more detail. Mass transfer coefficient (kSa) of BuOH in the bioreactor was also characterized at different gas circulation rates and stirring speeds. In a fermentation of glycerol with FG stripping at a relatively high gas flow rate (7 vvm) as high as 39.2 g/L BuOH (total) and 53.7 g/L 1,3‐PDO can be simultaneously produced. The results are discussed in view of further process optimization and scale up.
College recovers from the brink of collapse to post record‐setting enrollment numbers
Authors: Sutton Halley
Published: August 2016

In 2014, Montreat College was on the verge of either a merger or a complete shutdown. It was only through the intervention of an anonymous $6 million donation in March of 2014 that Montreat was able to put into place needed changes to ensure that the campus not only survived, but thrived. Now, a little more than two years later, the small private Christian college in North Carolina is enjoying strong enrollment and aspiring to grow. Last fall, the college enrolled its highest number of new students since its founding in 1916, for a total of 1,000 students on campus. Officials now seek to double that enrollment within the next four years. Paul J. Maurer, president of Montreat, shared insights about what has helped advance the institution into a healthy position, including the expansion and addition of programs geared toward adult learners.
Consider implications of Brexit for international student mobility
Authors: Dennis Marguerite J.
Published: August 2016

If your school recruits international students or participates in study abroad programs, the result of the British vote to leave the European Union will likely impact your future international recruitment plans.
Aromatic Hydrocarbon Production from Eucalyptus urophylla Pyrolysis over Several Metal‐Modified ZSM‐5 Catalysts
Authors: Schultz Emerson L. , Mullen Charles A. , Boateng Akwasi A.
Published: August 2016

Metal‐modified HZSM‐5 catalysts were prepared by the ion exchange of NH4ZSM‐5 (SiO2/Al2O3=23) using Zn, Ga, Ni, and combinations thereof. The prepared catalysts were used to evaluate catalytic pyrolysis for the conversion of Eucalyptus urophylla to fuels and chemicals, specifically aromatic hydrocarbons, by using a micro‐scale pyrolysis reactor coupled with GC–MS. Two different biomass‐to‐catalyst ratios (1:5 and 1:10 w/w) were studied. The catalyst prepared with Ga by total ion exchange (Ga‐HZSM‐5 B, ≈7 wt % Ga) yielded the highest amount of aromatic hydrocarbons, whereas the catalysts modified with Ni produced the lowest yield of aromatic hydrocarbons. A correlation between the methane yield and benzene and p‐xylene selectivity was found for the catalysts, which was observed mainly for the Ni‐, Zn‐, and Ga‐Ni‐modified catalysts. The Ga‐modified catalysts were the most selective for xylenes, whereas the Ni‐based catalysts were the most selective for benzene production with a concurrent increase in methane production. The Zn‐modified catalysts were the most selective for toluene production.
High‐Performance Supercapacitor Electrode Materials from Chitosan via Hydrothermal Carbonization and Potassium Hydroxide Activation
Authors: Zhu Linfeng , Shen Feng , Smith Richard L. , Qi Xinhua
Published: August 2016

Nitrogen‐rich porous carbonaceous materials suitable for supercapacitor applications can be synthesized directly from chitosan using a hydrothermal treatment (250 °C, 14 h) that is followed by chemical activation of the carbonized solids with KOH (ca. 800 °C, 2 h). The synthesized chitosan‐derived carbonaceous materials (CDCMs) had high specific surface area (ca. 2200 m2 g−1), large pore volume (ca. 1.36 cm3 g−1), and high nitrogen content (ca. 6.3 %). When a current density of 0.5 A g−1 was applied to CDCM‐800 obtained at an activation temperature of 800 °C, specific capacitances of 231 and 305 F g−1 were achieved for 0.5 m K2SO4 and 6 m KOH aqueous electrolytes, respectively. Capacitances of 154 and 198 F g−1 were retained for the respective electrolytes at 20 Ag−1. CDCM‐800 had an energy density of 8.5 Wh kg−1 corresponding to a specific power of 1 kW kg−1 at 20 A g−1 in 6 m KOH aqueous electrolytes. The prepared carbonaceous materials retained 99 % of their properties for over 3000 cycles at 1 A g−1 in 0.5 m K2SO4. The nitrogen‐rich nanoporous carbonaceous materials have wide application in energy, electrical, chemical, analytic, separation, and catalysis.
Visible light photocatalytic activity of chitosan/poly(vinyl alcohol)/TiO2 nanocomposite for dye removal: taguchi‐based optimization
Authors: Rasoulifard Mohammad Hossein , Seyed Dorraji Mir Saeed , Mozafari Vahideh
Published: August 2016

This work describes the preparation of chitosan/poly (vinyl alcohol)/titanium dioxide (CS/PVA/TiO2) nanocomposite for its use as a photocatalyst under visible light irradiation. The prepared nanocomposite was characterized by Fourier transform infrared (FT‐IR) spectroscopy, X‐ray diffraction (XRD) and scanning electron microscopy (SEM). The photocatalytic activity of CS/PVA/TiO2 was evaluated by photocatalytic removal of acid red 14 (AR14) in aqueous solution as a model pollutant. A Taguchi orthogonal array experimental design with an L16 matrix was employed to optimize the factors affecting the photocatalytic efficiency of CS/PVA/TiO2 nanocomposite such as: pH, irradiation time, initial dye concentration, and nanocomposite dosage. The optimum conditions were found to be as follows: pH = 3; irradiation time = 120 min; initial dye concentration = 10 mg L−1, and nanocomposite dosage = 400 mg L−1. The pH was found to be the most effective factor for dye removal, followed by the nanocomposite dosage. The dye removal during visible‐CS/PVA/TiO2 process under optimal conditions followed the pseudo‐first‐order reaction model with the rate constants of 0.0188 min−1. The photocatalytic activity of CS/PVA/TiO2 nanocomposite dropped very slightly in five consecutive reaction cycles. © 2016 American Institute of Chemical Engineers Environ Prog, 36: 66–72, 2017
Shake table testing of an elevator system in a full‐scale five‐story building
Authors: Wang Xiang , Hutchinson Tara C. , Astroza Rodrigo , Conte Joel P. , Restrepo José I. , Hoehler Matthew S. , Ribeiro Waldir
Published: August 2016

This paper investigates the seismic performance of a functional traction elevator as part of a full‐scale five‐story building shake table test program. The test building was subjected to a suite of earthquake input motions of increasing intensity, first while the building was isolated at its base and subsequently while it was fixed to the shake table platen. In addition, low‐amplitude white noise base excitation tests were conducted while the elevator system was placed in three different configurations, namely, by varying the vertical location of its cabin and counterweight, to study the acceleration amplifications of the elevator components due to dynamic excitations. During the earthquake tests, detailed observation of the physical damage and operability of the elevator as well as its measured response are reported. Although the cabin and counterweight sustained large accelerations because of impact during these tests, the use of well‐restrained guide shoes demonstrated its effectiveness in preventing the cabin and counterweight from derailment during high‐intensity earthquake shaking. However, differential displacements induced by the building imposed undesirable distortion of the elevator components and their surrounding support structure, which caused damage and inoperability of the elevator doors. It is recommended that these aspects be explicitly considered in elevator seismic design. Copyright © 2016 John Wiley & Sons, Ltd.
Zebrafish embryo tolerance to environmental stress factors—Concentration–dose response analysis of oxygen limitation, pH, and UV-light irradiation
Authors: Andrade Thayres S. , Henriques Jorge F. , Almeida Ana Rita , Soares Amadeu M.V.M. , Scholz Stefan , Domingues Inês
Published: August 2016

During the last century the increase in the mean global temperatures has been shown to impact on freshwater physicochemical parameters such as pH, dissolved oxygen, or ultraviolet (UV) light abundance. Changes in these parameters could modify the toxicity of environmental pollutants. Therefore, in the present study, the authors studied the tolerance (survival and sublethal endpoints) of zebrafish (Danio rerio) embryos to variations in pH (3–12), dissolved oxygen (3.9–237 μmol/L) and UV intensity (55–467 mW/m2) using selected endpoints. Sublethal endpoint assessment included the quantification of hatching success, developmental delay, reduction of body length, frequency of edema, and morphological abnormalities. Median lethal concentrations (LC50s; 96-h) of 3.68 and 10.21 were determined for acid and alkaline pH, respectively. Embryo survival appeared to be relatively resistant to oxygen depletion with a 96-h LC50 of 0.42 mg/L. However, concentrations of 6 mg/L and below caused edema and developmental retardations. Continuous exposure to UV radiation affected zebrafish development by reducing survival and hatching rate and triggering a series of developmental abnormalities such as pericardial edema and deformities. A 72-h LC50 of 227 mW/m2 was derived from intensity–response modeling. By generation of concentration–response parameters the authors’ data provide a basis for the subsequent assessment of combined effect of environmental stress parameters and chemicals. Environ Toxicol Chem 2017;36:682–690. © 2016 SETAC
Aquatic fate of a double-stranded RNA in a sediment­­–water system following an over-water application
Authors: Fischer Joshua R. , Zapata Fatima , Dubelman Samuel , Mueller Geoffrey M. , Uffman Joshua P. , Jiang Changjian , Jensen Peter D. , Levine Steven L.
Published: August 2016

Determining the rate of biodegradation of double-stranded RNA (dsRNA) in the environment is an essential element of a comprehensive risk assessment of an RNA-based agricultural product. This information is used during problem formulation to define relevant routes and durations of environmental exposure for in planta–expressed dsRNA. Although exposure to biotechnology-derived crops expressing dsRNA traits in the aquatic environment is predicted to be minimal, little is known regarding the fate of dsRNA in these environments. To assess exposure to aquatic environments, a study was conducted to measure the rate of biodegradation of DvSnf7 dsRNA in aerobic water–sediment systems. Aquatic systems containing natural water and sediments that varied in physical and chemical characteristics were treated with dsRNA by applying DvSnf7 dsRNA directly to the water column. In the present study, DvSnf7 dsRNA dissipated rapidly from the water phase and was undetectable within 7 d as measured by QuantiGene (Affymetrix) and a sensitive insect bioassay in these diverse systems. Degradation kinetics estimated a half-life (time to 50% dissipation [DT50]) of less than 3 d and a time to 90% dissipation of approximately 4 d. Further analysis indicated that DvSnf7 dsRNA had DT50 values of less than 6 d in both sediment-free systems containing natural water and systems with only sediment. Taken together, the results of the present study indicate that dsRNA-based agricultural products rapidly degrade and consequently are unlikely to persist in aquatic environments. Environ Toxicol Chem 2017;36:727–734. © 2016 SETAC
Identifying barriers to hepatocellular carcinoma surveillance in a national sample of patients with cirrhosis
Authors: Goldberg David S. , Taddei Tamar H. , Serper Marina , Mehta Rajni , Dieperink Eric , Aytaman Ayse , Baytarian Michelle , Fox Rena , Hunt Kristel , Pedrosa Marcos , Pocha Christine , Valderrama Adriana , Kaplan David E
Published: August 2016

Hepatocellular carcinoma (HCC) is a leading cause of morbidity and mortality in cirrhosis patients. This provides an opportunity to target the highest‐risk population, yet surveillance rates in the United States and Europe range from 10% to 40%. The goal of this study was to identify barriers to HCC surveillance, using data from the Veterans Health Administration, the largest provider of liver‐related health care in the United States. We included all patients 75 years of age or younger who were diagnosed with cirrhosis from January 1, 2008, until December 31, 2010. The primary outcome was a continuous measure of the percentage of time up‐to‐date with HCC surveillance (PTUDS) based on abdominal ultrasound (secondary outcomes included computed tomography and magnetic resonance imaging). Among 26,577 patients with cirrhosis (median follow‐up = 4.7 years), the mean PTUDS was 17.8 ± 21.5% (ultrasounds) and 23.3 ± 24.1% when any liver imaging modality was included. The strongest predictor of increased PTUDS was the number of visits to a specialist (gastroenterologist/hepatologist and/or infectious diseases) in the first year after cirrhosis diagnosis; the association between visits to a primary care physician and increasing surveillance was very small. Increasing distance to the closest Veterans Administration center was associated with decreased PTUDS. There was an inverse association between ultrasound lead time (difference between the date an ultrasound was ordered and requested exam date) and the odds of it being performed: odds ratio = 0.77, 95% confidence interval 0.72‐0.82 when ordered > 180 days ahead of time; odds ratio = 0.90, 95% confidence interval 0.85‐0.94 if lead time 91‐180 days. Conclusions: The responsibility for suboptimal surveillance rests with patients, providers, and the overall health care system; several measures can be implemented to potentially increase HCC surveillance, including increasing patient–specialist visits and minimizing appointment lead time. (Hepatology 2017;65:864‐874).
Patient‐reported barriers are associated with lower hepatocellular carcinoma surveillance rates in patients with cirrhosis
Authors: Farvardin Sherean , Patel Jaimin , Khambaty Maleka , Yerokun Olutola A. , Mok Huram , Tiro Jasmin A. , Yopp Adam C. , Parikh Neehar D. , Marrero Jorge A. , Singal Amit G.
Published: August 2016

Over 20% of patients with cirrhosis are nonadherent with hepatocellular carcinoma (HCC) surveillance recommendations; however, few studies have evaluated the impact of patient‐level factors on surveillance receipt. We characterized the association between HCC surveillance receipt and patient knowledge, attitudes, and perceived barriers in a racially diverse and socioeconomically disadvantaged cohort of patients with cirrhosis. Patients with cirrhosis followed at a large urban hospital were invited to complete a survey about HCC surveillance between August 2014 and December 2015. Multivariable logistic regression was performed to identify factors associated with HCC surveillance receipt during the 12‐month period preceding and 6‐month period after survey administration. We achieved a response rate of 71.8% (n = 541 of 753). Patients demonstrated high levels of HCC‐related knowledge (summary score, 77.7%); however, 48.6% believed that eating a healthy diet precluded the need for HCC surveillance, and 34.0% believed that HCC surveillance was not necessary if they had a normal physical exam and/or lacked clinical symptoms. Patients expressed worry about developing and dying from HCC, but nearly half (49.9%) of patients reported barriers to receiving HCC surveillance, including difficulty with the scheduling process (30.5%), costs of surveillance testing (25.3%), and transportation difficulties (17.3%). HCC surveillance receipt was significantly higher in patients who knew cirrhosis is a risk factor for developing HCC (odds ratio [OR], 3.09; 95% confidence interval [CI], 1.25‐7.62) and significantly lower in those reporting barriers to surveillance (OR, 0.42; 95% CI, 0.25‐0.70). Conclusion: Patients with cirrhosis are knowledgeable and interested in HCC surveillance; however, patient‐reported barriers are associated with lower surveillance rates in clinical practice and represent potential intervention targets to improve HCC surveillance effectiveness. (Hepatology 2017;65:875‐884).
The underreporting of hepatocellular carcinoma to the cancer register and a log‐linear model to estimate a more correct incidence
Authors: Törner Anna , Stokkeland Knut , Svensson Åke , Dickman Paul W. , Hultcrantz Rolf , Montgomery Scott , Duberg Ann‐Sofi
Published: August 2016

The Cancer Register (CR) in Sweden has reported that the incidence of primary liver cancer (PLC) has slowly declined over the last decades. Even though all cancers, irrespective of diagnostic method, should be reported to the CR, the PLC incidence may not reflect the true rate. Improved diagnostic tools have enabled diagnosis of hepatocellular carcinoma based on noninvasive methods without histological verification, possibly associated with missed cancer reports or misclassification in the CR. Our objective was to study the completeness and assess the underreporting of PLC to the CR and to produce a more accurate estimate based on three registers. The CR, the Cause of Death Register, and the Patient Register were investigated. Differences and overlap were examined, the incidence was estimated by merging data from the registers, and the number reported to none of the registers was estimated using a log‐linear capture‐recapture model. The results show that 98% of the PLCs reported to the CR were histologically verified; 80% were hepatocellular carcinoma and 20% were intrahepatic cholangiocarcinoma. Unspecified liver cancer decreased over time and constituted <10% of all reported liver cancers. The CR may underestimate the liver cancer incidence by 37%‐45%, primarily due to missed cancer reports. The estimated annual number of liver cancers increased over time, but the standardized incidence was stable around 11 per 100,000. Hepatitis C‐associated liver cancer increased and constituted 20% in 2010. Conclusion: There was an underreporting of PLC diagnosed by noninvasive methods; the incidence was considerably higher than estimated by the CR, with a stable incidence over time; reporting needs to improve and combining registers is recommended when studying incidence. (Hepatology 2017;65:885‐892).
Treatment of secondary central nervous system lymphoma with intrathecal rituximab, high‐dose methotrexate, and R‐DHAP followed by autologous stem cell transplantation: results of the HOVON 80 phase 2 study
Authors: Doorduijn Jeanette K. , van Imhoff Gustaaf W. , van der Holt Bronno , Schouten Harry C. , Schaafsma Martijn R. , MacKenzie Marius A. , Baars Joke W. , Kersten Marie José , Lugtenburg Pieternella J. , van den Bent Martin J. , Enting Roelien H. , Spoelstra Fokje M. , Poortmans Philip , Bromberg Jacoline E.C.
Published: August 2016

The prognosis of central nervous system (CNS) relapse of systemic non‐Hodgkin lymphoma is poor with 1‐year survival historically at 0% to 20%. Aiming to improve these results, we performed a multicenter phase 2 study in patients with a CNS relapse, with or without concurrent systemic relapse. Treatment consisted of 2 cycles of R‐DHAP alternating with high‐dose methotrexate (MTX) and was combined with intrathecal rituximab. Responding patients received a third R‐DHAP‐MTX cycle followed by busulfan and cyclophosphamide myeloablative therapy and autologous stem cell transplantation. In patients with persistent cerebrospinal fluid lymphoma after cycle 1, the intrathecal rituximab was replaced by intrathecal triple therapy, with MTX, cytarabine, and dexamethasone.

Thirty‐six patients were included. Eighteen had evidence of cerebrospinal fluid lymphoma, 24 had brain parenchymal disease, and 20 (56%) had concurrent systemic disease.

The overall response rate after 2 R‐DHAP‐MTX was 53% (19/36), with 22% (8/36) complete remission. Fifteen patients (42%) underwent a transplant. One‐year progression‐free survival was 19% (95% confidence interval, 9‐34): 25% in patients without and 15% in patients with systemic disease. One‐year overall survival was 25% (95% confidence interval, 12‐40).

This treatment regimen did not result in a major improvement of outcome of secondary CNS lymphoma, especially when concurrent systemic disease was present.

Registered in the Dutch trial register www.trialregister.nl, NTR1757; EudraCT number 2006‐002141‐37.
What Motivates Experts to Share? A Prospective Test of the Model of Knowledge‐Sharing Motivation
Authors: Stenius Minna , Haukkala Ari , Hankonen Nelli , Ravaja Niklas
Published: August 2016

Knowledge sharing is an employee behavior, critical to organizational success in knowledge‐intensive work environments. This study set out to empirically test the model of knowledge‐sharing motivation designed and presented in this journal by Gagné (2009). The model combines two established behavioral theories, the theory of planned behavior and self‐determination theory, and connects various human resource practices to it. This prospective survey study (n= 200) in a large expert organization employed structural equation modeling. The results mainly supported the proposed model, with attitudes, autonomous motivation, and sharing norms predicting knowledge‐sharing intentions (R2= .69), which predicted knowledge‐sharing behavior ( R2= .42). We also identified potential ways to modify the model to better suit typical knowledge‐sharing contexts. Implications for practice, with the emphasis on how our findings can benefit and be used by human resource management, are discussed. © 2016 Wiley Periodicals, Inc.
An Investigation on the Effect of Air Swirler Vane Angle on Liquid Fuel Combustion Characteristics
Authors: Pourhoseini S.H. , Fakhri Saeideh , Taheri Elmira , Asadi Rasool , Moghiman M.
Published: August 2016

This is an experimental and numerical study on the effect of air swirl vane angle on combustion characteristics of liquid fuel burners. The swirl vane angle varied in a range from 0° to 75° and the values of the dependent variables were determined. The flame temperature was measured by an S‐type thermocouple and a Testo 350 XL gas analyzer was used to determine the NO and CO pollutant concentrations. Also, sprint CFD code along with suitable models was used in analytical modeling. The results indicate that there is an optimum angle for the swirl vane (approximately 45° for the case study). At the optimum angle, the average temperature of the flame increases as much as 12.5% and 28.5% in comparison with small and large angles, respectively. Therefore, combustion efficiency reaches its maximum level and CO emission is at an extremely low level. The results also demonstrate that large swirl angles decreases NO emission.
A network theory approach for a better understanding of overland flow connectivity
Authors: Masselink Rens J. H. , Heckmann Tobias , Temme Arnaud J. A. M. , Anders Niels S. , Gooren Harm P. A. , Keesstra Saskia D.
Published: August 2016

Hydrological connectivity describes the physical coupling (linkages) of different elements within a landscape regarding (sub‐) surface flows. A firm understanding of hydrological connectivity is important for catchment management applications, for example, habitat and species protection, and for flood resistance and resilience improvement. Thinking about (geomorphological) systems as networks can lead to new insights, which has also been recognized within the scientific community, seeing the recent increase in the use of network (graph) theory within the geosciences. Network theory supports the analysis and understanding of complex systems by providing data structures for modelling objects and their linkages, and a versatile toolbox to quantitatively appraise network structure and properties. The objective of this study was to characterize and quantify overland flow connectivity dynamics on hillslopes in a humid sub‐Mediterranean environment by using a combination of high‐resolution digital‐terrain models, overland flow sensors and a network approach. Results showed that there are significant differences between overland flow connectivity on agricultural areas and semi‐natural shrubs areas. Significant positive correlations between connectivity and precipitation characteristics were found. Significant negative correlations between connectivity and soil moisture were found, most likely because of soil water repellency and/or soil surface crusting. The combination of structural networks and dynamic networks for determining potential connectivity and actual connectivity proved a powerful tool for analysing overland flow connectivity. Copyright © 2016 John Wiley & Sons, Ltd.
Future needs and recommendations in the development of species sensitivity distributions: Estimating toxicity thresholds for aquatic ecological communities and assessing impacts of chemical exposures
Authors: Belanger Scott , Barron Mace , Craig Peter , Dyer Scott , Galay-Burgos Malyka , Hamer Mick , Marshall Stuart , Posthuma Leo , Raimondo Sandy , Whitehouse Paul
Published: August 2016

A species sensitivity distribution (SSD) is a probability model of the variation of species sensitivities to a stressor, in particular chemical exposure. The SSD approach has been used as a decision support tool in environmental protection and management since the 1980s, and the ecotoxicological, statistical, and regulatory basis and applications continue to evolve. This article summarizes the findings of a 2014 workshop held by the European Centre for Toxicology and Ecotoxicology of Chemicals and the UK Environment Agency in Amsterdam, The Netherlands, on the ecological relevance, statistical basis, and regulatory applications of SSDs. An array of research recommendations categorized under the topical areas of use of SSDs, ecological considerations, guideline considerations, method development and validation, toxicity data, mechanistic understanding, and uncertainty were identified and prioritized. A rationale for the most critical research needs identified in the workshop is provided. The workshop reviewed the technical basis and historical development and application of SSDs, described approaches to estimating generic and scenario-specific SSD-based thresholds, evaluated utility and application of SSDs as diagnostic tools, and presented new statistical approaches to formulate SSDs. Collectively, these address many of the research needs to expand and improve their application. The highest priority work, from a pragmatic regulatory point of view, is to develop a guidance of best practices that could act as a basis for global harmonization and discussions regarding the SSD methodology and tools. Integr Environ Assess Manag 2017;13:664–674. © 2016 SETAC

Key Points

Species sensitivity distributions (SSDs) are probability models that summarize variation of species sensitivities to chemical exposure. SSDs are used in risk assessment and the derivation of environmental quality standards, because they can be used to develop community-level thresholds and have advantages over deterministic assessment approaches. The 2014 ECETOC and UK Environment Agency workshop summarized research needs to expand and improve application of SSDs. The highest priority work is to develop a guidance of best practices to drive global harmonization and discussions regarding SSD methodology and tools.
Patient Characteristics and Patient Behavior as Predictors of Outcome in Cognitive Therapy and Exposure Therapy for Hypochondriasis
Authors: Richtberg Samantha , Jakob Marion , Höfling Volkmar , Weck Florian
Published: August 2016

Objective

Psychotherapy for hypochondriasis has greatly improved over the last decades and cognitive‐behavioral treatments are most promising. However, research on predictors of treatment outcome for hypochondriasis is rare. Possible predictors of treatment outcome in cognitive therapy (CT) and exposure therapy (ET) for hypochondriasis were investigated.

Method

Characteristics and behaviors of 75 patients were considered as possible predictors: sociodemographic variables (sex, age, and cohabitation); psychopathology (pretreatment hypochondriacal symptoms, comorbid mental disorders, and levels of depression, anxiety, and somatic symptoms); and patient in‐session interpersonal behavior.

Results

Severity of pretreatment hypochondriacal symptoms, comorbid mental disorders, and patient in‐session interpersonal behavior were significant predictors in multiple hierarchical regression analyses. Interactions between the predictors and the treatment (CT or ET) were not found.

Conclusions

In‐session interpersonal behavior is an important predictor of outcome. Furthermore, there are no specific contraindications to treating hypochondriasis with CT or ET.
Unique Regulatory Mechanisms for the Human Embryonic Stem Cell Cycle
Authors: VanOudenhove Jennifer J. , Grandy Rodrigo A. , Ghule Prachi N. , Lian Jane B. , Stein Janet L. , Zaidi Sayyed K. , Stein Gary S.
Published: August 2016

The cell cycle in pluripotent human embryonic stem cells is governed by unique mechanisms that support unrestricted proliferation and competency for endodermal, mesodermal, and ectodermal differentiation. The abbreviated G1 period with retention of uncompromised fidelity for genetic and epigenetic mechanisms operative in control of proliferation support competency for expansion of the pluripotent cell population that is fundamental for initial stages of development. Regulatory events during the G1 period of the pluripotent cell cycle are decisive for the transition from pluripotency to lineage commitment. Recent findings indicate that a G2 cell cycle pause is present in both endodermal and mesodermal lineage cells, and is obligatory for differentiation to endoderm. J. Cell. Physiol. 232: 1254–1257, 2017. © 2016 Wiley Periodicals, Inc.
Evaluation of Aztreonam Dosing Regimens in Patients With Normal and Impaired Renal Function: A Population Pharmacokinetic Modeling and Monte Carlo Simulation Analysis
Authors: Xu Hongmei , Zhou Wangda , Zhou Diansong , Li Jianguo , Al‐Huniti Nidal
Published: August 2016

Aztreonam is a monocyclic β‐lactam antibiotic often used to treat infections caused by Enterobacteriaceae or Pseudomonas aeruginosa. Despite the long history of clinical use, population pharmacokinetic modeling of aztreonam in renally impaired patients is not yet available. The aims of this study were to assess the impact of renal impairment on aztreonam exposure and to evaluate dosing regimens for patients with renal impairment. A population model describing aztreonam pharmacokinetics following intravenous administration was developed using plasma concentrations from 42 healthy volunteers and renally impaired patients from 2 clinical studies. The final pharmacokinetic model was used to predict aztreonam plasma concentrations and evaluate the probability of pharmacodynamic target attainment (PTA) in patients with different levels of renal function. A 2‐compartment model with first‐order elimination adequately described aztreonam pharmacokinetics. The population mean estimates of aztreonam clearance, intercompartmental clearance, volume of distribution of the central compartment, and volume of distribution of the peripheral compartment were 4.93 L/h, 9.26 L/h, 7.43 L, and 6.44 L, respectively. Creatinine clearance and body weight were the most significant variables to explain patient variability in aztreonam clearance and volume of distribution, respectively. Simulations using the final pharmacokinetic model resulted in a clinical susceptibility break point of 4 and 8 mg/L, respectively, based on the clinical use of 1‐ and 2‐g loading doses with the same or reduced maintenance dose every 8 hours for various renal deficiency patients. The population pharmacokinetic modeling and PTA estimation support adequate PTAs (>90% PTA) from the aztreonam label for dose adjustment of aztreonam in patients with moderate and severe renal impairment.
Synthesis, Nematocidal Activity and Docking Study of Novel Chiral 1‐(3‐Chloropyridin‐2‐yl)‐3‐(difluoromethyl)‐1H‐pyrazole‐4‐carboxamide Derivatives
Authors: Zhao Wen , Shen Zhong‐Hua , Xu Tian‐Ming , Peng Wei‐Li , Liu Xing‐Hai
Published: August 2016

A novel series of pyrazole carboxamide derivatives had been designed, synthesized and some of them exhibited good nematocidal activity.
Can reduced field‐of‐view diffusion sequence help assess microsatellite instability in FIGO stage 1 endometrial cancer?
Authors: Bhosale Priya , Ramalingam Preetha , Ma Jingfei , Iyer Revathy , Soliman Pamela , Frumovitz Micheal , Kundra Vikas
Published: August 2016

Purpose

To determine if a reduced‐field‐of‐view (rFOV) diffusion intravoxel incoherent motion (IVIM) sequence can differentiate the imaging characteristics of tumors with microsatellite instability (MSI) from those that are microsatellite stable (MSS) in patients with clinical FIGO stage IA endometrial cancer and if MRI can be used to determine MSI status.

Materials and Methods

Sagittal rFOV diffusion‐weighted images were obtained in 12 patients on a 3T scanner using six b‐values (0, 50, 100, 150, 200, and 600). These images were used to derive apparent diffusion coefficient (ADC), true diffusion coefficient (Dt), pseudodiffusion (D*), and perfusion fraction (f). Regions of interest (ROIs) were drawn on the dynamic contrast‐enhanced magnetic resonance imaging (MRI) sequence on an Advantage Windows workstation and were copied to the same location on IVIM‐derived images. The ROI mean of these images was recorded and compared with the microsatellite status. The depth of myometrial invasion and IVIM‐derived parameters were tabulated by microsatellite status. The Wilcoxon rank sum test was used to compare T1 postcontrast images and IVIM‐derived images and microsatellite status.

Results

Six patients had MSS tumors and six had MSI tumors. MSS tumors had a significantly higher ADC value (P = 0.03) and Dt (P = 0.045) than the MSI tumors. There was no association between < and ≥ 50% depth of myometrial invasion (measured on pathology and MRI analysis) and MSI stability P > 0.99.

Conclusion

IVIM, ADC and Dt may be able to determine microsatellite status noninvasively in patients with clinical FIGO stage I endometrial cancer.

Level of Evidence: 1

J. Magn. Reson. Imaging 2017;45:1216–1224