bluuebunny/crossref_metadata_2025 huggingface dataset:
MABO‐TSCH: Multihop and blacklist‐based optimized time synchronized channel hopping
Authors: Gomes Pedro Henrique , Watteyne Thomas , Krishnamachari Bhaskar
Published: August 2017

Emerging Industrial Internet of Things applications, such as smart factories, require reliable communication and robustness against interference from colocated wireless systems. To address these challenges, frequency‐hopping spread spectrum has been used by different protocols, including IEEE802.15.4‐2015 TSCH. Frequency‐hopping spread spectrum can be improved with the aid of blacklists to avoid bad frequencies. The quality of channels in most environments shows significant spatial‐temporal variation, which limits the effectiveness of simple blacklisting schemes. In this article, we propose an enhanced blacklisting solution to improve the TSCH protocol. The proposed algorithms work in a distributed fashion, where each pair of receiver/transmitter nodes negotiates a local blacklist, based on the estimation of packet delivery ratio. We model the channel quality estimation as a multiarmed bandit problem and show that it is possible to create blacklists that provide results close to optimal without any separate learning phase. The proposed algorithms are implemented in OpenWSN and evaluated through simulations in 2 different scenarios with about 40 motes and experiments using an indoor testbed with 40 TelosB motes.
Time series forecasting using evolutionary neural nets implemented in a volunteer computing system
Authors: Rivas V.M. , Parras‐Gutiérrez E. , Merelo J.J. , Arenas M.G. , García‐Fernández P.
Published: August 2017

jsEvRBF is a time‐series forecasting method based on genetic algorithm and neural nets. Written in JavaScript language, can be executed in most web browsers. Consequently, everybody can participate in the experiments, and scientists can take advantage of nowadays available browsers and devices as computation environments. This is also a great challenge as the language support and performance varies from one browser to another. In this paper, jsEvRBF has been tested in a volunteer computing experiment, and also in a single‐browser one. Both experiments are related to forecasting currencies exchange, and the results show the viability of the proposal.
Low density polyethylene functionalized with antibiofilm compounds inhibits Escherichia coli cell adhesion
Authors: Dell'orto Silvia , Cattò Cristina , Villa Federica , Forlani Fabio , Vassallo Espedito , Morra Marco , Cappitelli Francesca , Villa Stefania , Gelain Arianna
Published: August 2017

The present work concerns an efficient strategy to obtain novel medical devices materials able to inhibit biofilm formation. The new materials were achieved by covalent grafting of p‐aminocinnamic or p‐aminosalicylic acids on low density polyethylene coupons. The polyethylene surface, previously activated by oxygen plasma treatment, was functionalized using 2‐hydroxymethylmetacrylate as linker. The latter was reacted with succinic anhydride affording the carboxylic end useful for the immobilization of the antibiofilm molecules. The modified surface was characterized by scanning electron microscope, X‐ray photoelectron spectroscopy, attenuated total reflectance Fourier transform infrared and fluorescence analyses. The antibiofilm activity of the modified materials were tested against Escherichia coli biofilm grown in the Center of Disease Control biofilm reactor. The results revealed that the grafted cinnamic and salicylic acid derivatives reduced biofilm biomass, in comparison with the control, by 73.7 ± 10.7% and 63.4 ± 7.1%, respectively. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 3251–3261, 2017.
Synthesis, Structural Characterization, and Electrochemical Properties of Isotruxene–Polyaniline Hybrid Systems
Authors: Tan Wei Shyang , Lin Shang‐Yin , Yang Jye‐Shane
Published: August 2017

The synthesis, structural characterization, and electrochemical properties of a series of isotruxene–polyaniline (PANI) hybrid systems (SITPs, SITAs, and CITs) are reported. The syntheses were performed by in situ chemical oxidative polymerization of aniline in the presence of isotruxene additives ITP and/or ITA at specific aniline‐to‐additive molar ratios. The polymers SITPs and SITAs display granular morphology, but for the polymers CITs a spherical morphology with a diameter of 300–500 nm is found. These hybrid systems display electrochemical capacitive performance superior to those of the parent PANI prepared under the same condition (e.g., 385–463 vs. 181 F/g at 3 mA/cm2 current density during charge–discharge test). Molecular (star‐shaped or hyperbranched vs. linear topology) and supramolecular (isotruxene–PANI π–π and cation–π interactions) models in accounting for the observed morphology and electrochemical properties are provided.
Effect of fed‐batch and semicontinuous regimen on Nannochloropsis oculata grown in different culture media to high‐value products
Authors: Martínez‐Macías Rosario , Meza‐Escalante Edna , Serrano‐Palacios Denisse , Gortáres‐Moroyoqui Pablo , Ruíz‐Ruíz Patricia Elizabeth , Ulloa‐Mercado Gabriela
Published: August 2017

BACKGROUND

High cell density in cultures of microalgae is a key factor to recover biomass and extract metabolites of interest. A fed batch tubular reactor (FBTR) and semi‐continuous reactor (SCR) with f/2 Guillard Medium (f/2GM) and algal medium (AM) were evaluated. Both modes were operated under completely defined conditions to assess their effect on cell density, and lipid, protein and carbohydrate productivity of the microalgae Nannochloropsis oculata.

RESULTS

Results show that the FBTR promotes the highest cell density for both culture media, achieving 525 ± 1.84×106 cell mL‐1. With AM in the SCR, specific growth rate, productivities of biomass and lipids were the highest, as well as content of protein (48%), lipid (52.1%) and carbohydrates (17%). No significant differences were found in saturated fatty acids composition, whereas unsaturated fatty acids composition was affected by the operating regimen, this being higher in the FBTR.

CONCLUSION

The use of AM in both operating modes, FBTR and SCR, increased the cell density and improved the lipid content of N. oculata. A good option would be to combine both culture modes; first, use the FBTR to obtain high cell densities and then apply the SCR mode to increase lipid productivity; finally, an important quantity of high‐value products could be recovered. © 2017 Society of Chemical Industry
Harnessing soybean hulls for improved polygalacturonase production by Aspergillus sojae through fine‐tuning of ambient pH
Authors: Fratebianchi Dante , Acosta Marina Alejandra , Cavalitto Sebastián Fernando
Published: August 2017

BACKGROUND

Soybean hulls result from the processing of the bean for producing oil and protein products. This by‐product generated massively in America has virtually no commercial value, so substantial effort is being applied to its exploitation for generating value‐added goods. This work evaluates soybean hulls as inducer of the production of pectinolytic enzymes, through optimization studies regarding polygalacturonase production by Aspergillus sojae in submerged cultures.

RESULTS

A 2‐fold improvement in polygalacturonase yield was found by varying the initial pH of the culture in a very narrow acid pH range (2.40–2.80). The optimized fermentation process was successfully transferred to stirred‐tank bioreactors in terms of volumetric productivity, and final polygalacturonase yields were 42 U mL‐1 and 1.39 U g‐1 soybean hulls, which are among the highest reported with this by‐product. Morphological characterization of A. sojae during cultivation showed that the fungus mainly developed in dispersed mycelia at initial pH of 2.40–2.80 while, conversely, fungal pellets predominated in cultures performed at initial pH of 5.40.

CONCLUSION

High enzyme titers are possibly connected to the formation of dispersed mycelia, as well as to acid‐induced expression of the respective gene/s. It is foreseen that this data will be helpful regarding the production of fungal pectinases or other acid‐induced enzymes. © 2017 Society of Chemical Industry
Relative cerebral blood volume is a potential biomarker in late delayed radiation‐induced brain injury
Authors: Xie Ying , Huang Haiwei , Guo Junjie , Zhou Dongxiao
Published: August 2017

Purpose

To assess whether relative cerebral blood volume (rCBV) can provide information to reliably evaluate the stages of late delayed radiation‐induced brain injury.

Materials and Methods

Forty patients diagnosed with late delayed radiation‐induced brain injury were enrolled. The patients were examined using a 1.5T magnetic resonance imaging (MRI) system equipped with an 8‐channel head coil. An echo planar imaging (EPI) sequence was used in perfusion‐weighted imaging (PWI). The location of 1H‐MR spectroscopy scanning was acquired by a point‐resolved spectroscopy sequence. Lesions of the temporal lobe were divided into one of two groups according to rCBV value: rCBV<1 (low rCBV [group 1; n = 45]); and rCBV>1 (elevated rCBV [group 2; n = 14]). PWI and MRS parameters, as well as morphological lesion types, in these two groups were compared. Morphological severity was assessed independently and agreed on by two imaging specialists (J.L. and H.X.S., with 16 and 24 years' experience, respectively). If necessary, a third imaging professor (Z.M.H.) with 30 years' experience resolved disagreement(s). Standards for evaluating morphological lesion types were based on previously published criteria. After testing the skewness of data, the Mann–Whitney U‐test or Student's t‐test was used, as appropriate.

Results

rCBV, relative cerebral blood flow (rCBF), and relative mean transit time (rMTT) in group 2 (n = 14) were significantly higher than in group 1 (n = 45) (rCBV: 1.21 ± 0.38 vs. 0.72 ± 0.32, respectively; P < 0.001; rCBF: 1.13 ± 0.02 vs. 0.74 ± 0.04, respectively; P < 0.001; rMTT: 1.10 ± 0.26 vs. 0.96 ± 0.20, P < 0.001). The levels of choline‐containing compounds (CHO) / creatine (Cr) and CHO/N‐acetylaspartate (NAA) in group 1 were significantly greater than in group 2 (CHO/Cr: 1.89 ± 1.83 vs. 1.22 ± 1.31, respectively; P = 0.016; CHO/NAA: 1.85 ± 3.50 vs. 1.17 ± 0.75, respectively; P = 0.022). More severe morphological lesions were present in lesions with low rCBV compared with elevated rCBV (overall severity: 7.00 ± 4.25 vs. 5.00 ± 5.13, respectively; P = 0.029).

Conclusion

Elevated rCBV accompanied by a more conservative metabolic pattern and milder lesion(s) may represent a less advanced stage in the development of late delayed radiation‐induced brain injury.

Level of Evidence: 4

Technical Efficacy: Stage 3

J. Magn. Reson. Imaging 2018;47:1112–1118.
Nitrogen fixing potential of various heterotrophic Bacillus strains from a tropical estuary and adjacent coastal regions
Authors: Yousuf Jesmi , Thajudeen Jabir , Rahiman Mujeeb , Krishnankutty Soumya , P. Alikunj Aneesa , A. Abdulla Mohamed H.
Published: August 2017

In the present study, we report the nitrogen fixing potential of heterotrophic diazotrophs isolated from a tropical estuary and adjacent coastal sea. Results of the study revealed that most of the species that are capable of fixing nitrogen in the study area belongs to the genus Bacillus. The isolates from the estuary showed maximum homology with Bacillus megaterium, B. cereus, B. safencis, B. licheniformis, B. aerophilus, B. oceanisediminis, B. flexus, B. aquimaris, B. vietnamensis, and B. subterraneaus, whereas the diazotrophic isolates from coastal samples were closely related to B. subtilis, B. megaterium, B. circulans, B. aerophilus, B. flexus, and B. oceanisediminis. Experimental studies to determine the nitrogen fixation potential of isolates revealed considerable variation among different strains and the highest nitrogen fixing potential was recorded in B. megaterium (210.05 ± 7.0 nmol C2H4/mg protein/day) followed by B. flexus (108.76 ± 3.66 nmol C2H4/mg protein/day) and B. circulans (98.28 ± 4.32 nmol C2H4/mg protein/day). Molecular basis of nitrogen fixation by these heterotrophic Bacillus strains has been explored in terms of the presence of nifH gene in them. We observed that heterotrophic Bacillus sp. have potential ability to fix nitrogen.
Sea surface temperature variability along the Portuguese coast since 1950
Authors: Baptista Vânia , Silva Patrícia Laginha , Relvas Paulo , Teodósio M. Alexandra , Leitão Francisco
Published: August 2017

Overall an increase in sea surface temperature (SST) has been recorded over the last century. However, changes in SST are not homogeneous across the ocean. Most studies focus on the processes and mechanisms setting SST variability across broad scales and neglect changes occurring at a regional scale. So, this study aims to describe annual, seasonal and monthly time‐series trends in SST along the Portuguese coast, compare trends among areas (Northwest, Southwest and South), quantify SST increase rates and SST time‐series discontinuities. Time‐series analyses showed that SST has the same annual and monthly trend regardless of the area and data sets used (ICOADS: 1950–2010; Satellite data: 1985–2010). SST increased in the three areas: +0.1 °C decade−1 in Northwestern and Southwestern coasts (the same than global average), +0.2 °C decade−1 in the Southern coast. The higher monthly SST increment rates were observed in spring and summer (satellite data: +0.4 °C decade−1 in June in Northwest; +0.4 °C decade−1 in April in Southwest; +0.5 °C decade−1 in June in South). Discontinuities, that is, sudden shifts in time‐series, were observed after 1987, 1995 and 1982–1983 in the Northwest, Southwest and Southern areas, respectively. Overall, this study reinforces the hypothesis that SST varies regionally; so, studies assessing the impacts inherent to climate change along coastal areas, namely fisheries variability, ought to have this perspective into account.
Enterprise risk management: A global focus on standardization
Authors: Kline James J. , Hutchins Greg
Published: August 2017

As organizations become increasingly interconnected, their leaders are recognizing the importance of incorporating enterprise risk management (ERM) into their strategic planning and quality improvement efforts. A detailed examination of recent risk events, as well as the ERM provisions of ISO 9001:2015 and the US Office of Management and Budget's Circular A‐123, highlights the forces driving the widespread adoption of ERM practices in both private and public organizations.
Effects of combined teriparatide and zoledronic acid on posterior lumbar vertebral fusion in an aged ovariectomized rat model of osteopenia
Authors: Yishake Mumingjiang , Yasen Miersalijiang , Jiang Libo , Liu Wangmi , Xing Rong , Chen Qian , Lin Hong , Dong Jian
Published: August 2017

There has been no study regarding the effect of a combination of teriparatide (TPTD) and zoledronic acid (ZA) on vertebral fusion. In this study, we investigate the effect of single and combined TPTD and ZA treatment on lumbar vertebral fusion in aged ovariectomized (OVX) rats. Sixty two‐month‐old female Sprague‐Dawley rats were ovariectomized and underwent bilateral L4–L5 posterolateral intertransverse fusion after 10 months. The OVX rats received vehicle (control) treatment, or ZA (100 µg/kg, once), or TPTD (60 µg/kg/2 d for 42 d), or ZA + TPTD until they were euthanized at 6 weeks following lumbar vertebral fusion. The lumbar spine was harvested. Bone mineral density (BMD), bone fusion, bone volume (BV), and bone formation rate (BFR)were analyzed by dual‐energy X‐ray absorptiometry (DXA), radiography, micro‐computed tomography, and histomorphometry. Compared with vehicle (control) treatment, ZA and TPTD monotherapy increased bone volume (BV) at fusion site, and ZA + TPTD combined therapy had an additive effect. Treatment with TPTD and ZA + TPTD increased the bone fusion rate when compared with the control group. ZA monotherapy did not alter the rate of bone fusion. The TPTD and ZA + TPTD treatment groups had increased mineral apposition rate (MAR), mineralizing surfaces/bone surface ((MS/BS), and BFR/BS compared with the OVX group. Our experiment confirm that the monotherapy with TPTD and combination therapy with ZA + TPTD in an OVX rat model of osteopenia following lumbar vertebral fusion surgery increased bone fusion mass and bone fusion rate, and ZA + TPTD combined therapy had an additive effect on bone fusion mass. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:937–944, 2018.
Heat treatment as postharvest tool for improving quality in extra‐early nectarines
Authors: Falagán Natalia , Artés Francisco , Aguayo Encarna
Published: August 2017

BACKGROUND

Extra‐early nectarine cultivars such as ‘VioWhite 5’ could present a lack of organoleptic and nutritional quality. Heat treatments (HT) can be applied to improve their primary characteristics. In this experiment, control (non‐treated), HT1 (3 h; 45 °C) and HT2 (2 h; 50 °C) were studied. Fruit were stored (10 days; 0 ± 0.5 °C; 90–95% RH) followed by a simulated retail sale period (3 days; 15 °C; 70–75% RH).

RESULTS

HT fruit showed higher weight loss (2.76 ± 0.06% and 3.32 ± 0.01% for HT1 and HT2, respectively; vs. 2.23 ± 0.14% for control) and lower firmness than control samples (28.88% and 21.67% less for HT1 and HT2, respectively). HT treatments induced an increase in soluble solids content and a decrease in total acidity, which led to a better sensory quality. These changes were positively received by consumers. Total antioxidant capacity was enhanced by HT due to an increase in phenolic compound content. A higher enzymatic activity was found in pectin methylesterase and polygaracturonase in HT nectarines when compared to control.

CONCLUSION

The application of HT on extra‐early nectarine cv. demonstrated a strong potential to improve consumption quality in the industry. © 2017 Society of Chemical Industry
Peer review: The experience and views of early career researchers
Authors: Rodríguez‐Bravo Blanca , Nicholas David , Herman Eti , Boukacem‐Zeghmouri Chérifa , Watkinson Anthony , Xu Jie , Abrizah Abdullah , Świgoń Marzena
Published: August 2017

This paper presents selected findings from the first year of a 3‐year longitudinal study of early career researchers (ECRs), which sought to ascertain current and changing habits in scholarly communication. Specifically, the aims of the paper are to show: (1) how much experience and knowledge ECRs had of peer review – both as authors and as reviewers; (2) what they felt the benefits were and what suggestions they had for improvement; (3) what they thought of open peer review (OPR); and (4) who they felt should organize peer review. Data were obtained from 116 science and social science ECRs, most of whom had published and were subject to in‐depth interviews conducted face‐to‐face, via Skype, or over the telephone. An extensive literature review was also conducted to provide a context and supplementary data for the findings. The main findings were that: (1) most ECRS are well informed about peer review and generally like the experience, largely because of the learning experiences obtained; (2) they like blind double‐peer review, but would like some improvements, especially with regards to reviewer quality; (3) most are uncomfortable with the idea of OPR; and (4) most would like publishers to continue organizing peer review because of their perceived independence.
Rewarding customers who keep a product: How reinforcement affects customers' product return decision in online retailing
Authors: Gelbrich Katja , Gäthke Jana , Hübner Alexander
Published: August 2017

A lenient product return policy represents the status quo of current return management practice in online retailing because it increases customers' order tendency. However, at the same time, many customers tend to return products under this policy, which incurs considerable costs for retailers. The present research introduces a keep reward (i.e., providing incentives to keep a product) as a new promotion strategy to improve the conventional lenient policy. Drawing on operant conditioning, the authors propose and test the reinforcing effect of a keep reward on customers' keep decision, compared to the conventional lenient policy. Results of a qualitative pilot study suggest that a keep reward is generally feasible in online retailing practice, especially in the low‐ to mid‐price segment and with rewards that are linked to future purchases. Two experimental studies verify the positive effect of a keep reward. Study 1 shows that it substantially increases keep intention compared to a conventional lenient policy. Study 2 shows that the effect on keep intention is moderated by customers' online shopping frequency, and this moderating effect is mediated by repurchase intention. In particular, the keep reward is most effective among frequent shoppers because they are more inclined to repurchase and thus, benefit from the reward. In summary, both studies support the keep reward as a valuable add‐on to the conventional lenient policy because order intention remains comparably high, while keep intention is higher. Theoretical implications and recommendations for online retailers on how to implement a keep reward in different industries are discussed.
Understanding the role of social influence in piquing curiosity and influencing attitudes and behaviors in a social network environment
Authors: Thomas Veronica L. , Vinuales Gema
Published: August 2017

Social networks provide an innovative means for facilitating social influence as well as arousing consumer curiosity. However, research on how social influence impacts attitudes and behaviors in this context is limited. Further, even less research exists examining how curiosity impacts consumers’ behaviors, which is concerning since curiosity may be especially relevant in an online setting. To overcome these gaps, two studies were conducted which demonstrate that a consumer's curiosity toward a social network post is influenced by the group membership of the individual who created the post. In turn, curiosity leads to more positive attitudes toward the experience described or represented in the post, which leads to higher intentions to undertake that experience. Additionally, consumer susceptibility to interpersonal influence is found to moderate the relationship between group membership and curiosity. If susceptibility to interpersonal influence is strong enough, content posted by a dissociative group member can also arouse curiosity and positively influence attitudes and behavioral intentions.
Branding with the in–out effect: The impact of consonantal articulation on brand evaluation
Authors: Godinho Sandra , V. Garrido Margarida
Published: August 2017

Recent research has shown that mouth movements, produced even during silent reading, can affect stimulus evaluation. Words featuring systematic wanderings of consonantal stricture spots ranging from the front to the rear of the mouth (inward) are preferred to words with wanderings in the opposite direction (outward). In four experiments, the authors extended this in–out effect from a basic laboratory setting to a more ecologically relevant domain and examined the boundary conditions of possible applications to marketing. In this research, the inward/outward words presented were embedded in common brand imagery such as labels, logos, and product packages. Either with plain graphic information or with more visually informative packaging, inward names were always preferred (all p‐values < 0.001). These results indicate that concurrent information that competitively feeds into the preference judgment did not have diagnostic value when compared to the articulation direction. Such prevalence of the effect even when embedded in more complex stimulus emphasizes the relevance of investigating oral kinematics effects and the need to further research other sensorimotor phenomena in consumer behavior.
Global weak solutions for an attraction‐repulsion system with nonlinear diffusion
Authors: Li Dan , Mu Chunlai , Lin Ke , Wang Liangchen
Published: August 2017

This paper deals with the attraction‐repulsion chemotaxis system with nonlinear diffusion ut=∇·(D(u)∇u)−∇·(uχ(v)∇v)+∇·(uγξ(w)∇w), τ1vt=Δv−α1v+β1u, τ2wt=Δw−α2w+β2u, subject to the homogenous Neumann boundary conditions, in a smooth bounded domain
, where the coefficients αi, βi, and τi∈{0,1}(i=1,2) are positive. The function D fulfills D(u)⩾CDum−1 for all u>0 with certain CD>0 and m>1. For the parabolic‐elliptic‐elliptic case in the sense that τ1=τ2=0 and γ=1, we obtain that for any
and all sufficiently smooth initial data u0, the model possesses at least one global weak solution under suitable conditions on the functions χ and ξ. Under the assumption
, it is also proved that for the parabolic‐parabolic‐elliptic case in the sense that τ1=1, τ2=0, and γ⩾2, the system possesses at least one global weak solution under different assumptions on the functions χ and ξ.
Spine surface detection from local phase‐symmetry enhanced ridges in ultrasound images
Authors: Shajudeen Peer Mohamed S. , Righetti Raffaella
Published: August 2017

Purpose

Improper administration of epidural anesthesia can result in nerve complications. This problem is exacerbated for obese patients whose vertebrae cannot be palpated. Ultrasound (US) has recently emerged as an attractive imaging modality for accurate epidural placement. However, anesthesiologists untrained in US have difficulty interpreting the anatomy in noisy spinal US images. Furthermore, the complex geometry in spinal US images is characterized by a discontinuous intensity profile because the transducer is often not perpendicularly oriented to spine surface regions such as laminae, articular and transverse processes. This makes the interpretation of spinal images more challenging than typical long bone surface images. In this article, we propose a new method to segment the spine anatomy in US images obtained in both the transverse and paramedian planes.

Methods

A set of 108 B‐mode images were randomly chosen from 35 cine loops obtained from scanning the lumbar and thoracic vertebrae of 17 healthy volunteers with a BMI ranging from 19.5 to 27.9. A local phase‐symmetry technique was applied to the B‐mode images for enhancement of bone‐like ridges, and the spine blobs were subsequently classified. The segmented spine surface from the blobs was compared against a radiologist's manual delineation of the spine surface.

Results

For the performance of the spine blob classifier, we obtain a Matthews Correlation Coefficient (MCC) of 0.77 and a geometric mean (G‐mean) of 0.96. The mean absolute error between the manual delineation of the laminae by the radiologist and the automatic laminae segmentation is found to be 0.26 mm with a maximum possible absolute error of 2.01 mm for spinal US images of 70 mm depth.

Conclusions

Our proposed technique successfully performs automatic segmentation of the spine surface — specifically the laminae, ligamentum flava, spinous, transverse, and articular processes — and can be extended to any bone anatomy present in an US image. This has implications for 3D visualization of bone surfaces and, without loss of generality, the vertebral column.
Urinary bladder cancer staging in CT urography using machine learning
Authors: Garapati Sankeerth S. , Hadjiiski Lubomir , Cha Kenny H. , Chan Heang‐Ping , Caoili Elaine M. , Cohan Richard H. , Weizer Alon , Alva Ajjai , Paramagul Chintana , Wei Jun , Zhou Chuan
Published: August 2017

Purpose

To evaluate the feasibility of using an objective computer‐aided system to assess bladder cancer stage in CT Urography (CTU).

Materials and methods

A dataset consisting of 84 bladder cancer lesions from 76 CTU cases was used to develop the computerized system for bladder cancer staging based on machine learning approaches. The cases were grouped into two classes based on pathological stage ≥ T2 or below T2, which is the decision threshold for neoadjuvant chemotherapy treatment clinically. There were 43 cancers below stage T2 and 41 cancers at stage T2 or above. All 84 lesions were automatically segmented using our previously developed auto‐initialized cascaded level sets (AI‐CALS) method. Morphological and texture features were extracted. The features were divided into subspaces of morphological features only, texture features only, and a combined set of both morphological and texture features. The dataset was split into Set 1 and Set 2 for two‐fold cross‐validation. Stepwise feature selection was used to select the most effective features. A linear discriminant analysis (LDA), a neural network (NN), a support vector machine (SVM), and a random forest (RAF) classifier were used to combine the features into a single score. The classification accuracy of the four classifiers was compared using the area under the receiver operating characteristic (ROC) curve (Az).

Results

Based on the texture features only, the LDA classifier achieved a test Az of 0.91 on Set 1 and a test Az of 0.88 on Set 2. The test Az of the NN classifier for Set 1 and Set 2 were 0.89 and 0.92, respectively. The SVM classifier achieved test Az of 0.91 on Set 1 and test Az of 0.89 on Set 2. The test Az of the RAF classifier for Set 1 and Set 2 was 0.89 and 0.97, respectively. The morphological features alone, the texture features alone, and the combined feature set achieved comparable classification performance.

Conclusion

The predictive model developed in this study shows promise as a classification tool for stratifying bladder cancer into two staging categories: greater than or equal to stage T2 and below stage T2.
ELectron microscopic abnormality and therapeutic efficacy in chronic inflammatory demyelinating polyneuropathy with anti‐neurofascin155 immunoglobulin G4 antibody
Authors: Kuwahara Motoi , Suzuki Hidekazu , Oka Nobuyuki , Ogata Hidenori , Yanagimoto Satoshi , Sadakane Shuji , Fukumoto Yuta , Yamana Masaki , Yuhara Yoshiko , Yoshikawa Keisuke , Morikawa Miyuki , Kawai Shigeru , Okazaki Masahiro , Tsujimoto Toru , Kira Jun‐Ichi , Kusunoki Susumu
Published: August 2017

Introduction

Neurofascin155 (NF155) is a target antigen for autoantibodies in a subset of chronic inflammatory demyelinating polyneuropathy (CIDP).

Methods

We report the cases of 4 patients with anti‐NF155 immunoglobulin G4 (IgG4) antibody‐positive CIDP who underwent sural nerve biopsies.

Results

All patients were relatively young at onset. Three patients experienced tremors, and 2 patients had severe ataxia. Although the response to intravenous immunoglobulin was poor in all patients, plasma exchange and corticosteroids were at least partially effective. Immunoadsorption plasmapheresis was performed in 1 patient but was ineffective. Electron microscopic examination of sural nerve biopsies revealed loss of paranodal transverse bands in all patients.

Discussion

Anti‐NF155 IgG4 antibody‐positive CIDP shows distinctive clinicopathological features, indicating that the IgG4 antibody is directly associated with the pathogenic mechanisms of anti‐NF155 IgG4 antibody‐positive CIDP. Muscle Nerve 57: 498–502, 2018
Study on the surface morphology and wettability of nanocomposite films based on poly(methyl methacrylate) containing polyhedral oligomeric silsesquioxane/silica nanohybrids
Authors: Kargar Abjahan Toktam , Hejazi Iman , Hosseini Leya , Seyfi Javad , Davachi Seyed Mohammad , Khonakdar Hossein Ali
Published: August 2017

Superhydrophobic behavior was imparted on the surface of poly(methyl methacrylate) (PMMA) films using a hybrid of nanoparticles including polyhedral oligomeric silsesquioxane (POSS) and silica. To this end, an improved phase separation method based on the concurrent use of nonsolvent and nanoparticles was used. In the absence of nanoparticles, scanning electron microscopy (SEM) results revealed the surface segregation of PMMA macromolecules as the ethanol content was increased causing the roughness to be enhanced; however, no superhydrophobic property was attained. SEM and X‐ray photoelectron spectroscopy results demonstrated that POSS particles were be mainly localized at the bulk of the nanocomposite films, and thus, superhydrophobicity could not be achieved. Accordingly, hydrophobic silica nanoparticles were introduced to the formulation leading to the superhydrophobic behavior. The durability of the superhydrophobic samples was investigated by immersing the films into the solutions with different pH values under dynamic conditions. Despite its more initial hydrophobicity, the sample made via the concurrent use of nonsolvent and nanohybrid exhibited a poorer durability, which was attributed to the more porous structure and formation of large cracks at the surface layer of the films. The results of this study could be used as a hint of nanohybrids' efficiency in the fabrication of stable superhydrophobic surfaces. POLYM. COMPOS., 40:E127–E135, 2019. © 2017 Society of Plastics Engineers
Heterofunctional RAFT‐derived PNIPAM via cascade trithiocarbonate removal and thiol‐yne coupling click reaction
Authors: Le Bohec Maël , Piogé Sandie , Pascual Sagrario , Fontaine Laurent
Published: August 2017

An efficient one‐pot process to functionalize the α‐ and ω‐positions of RAFT‐derived poly(N‐isopropylacrylamide) (PNIPAM) by two inherently different mechanistic pathways is reported. The method relies on the RAFT polymerization of NIPAM using a new alkyne‐based RAFT agent, namely 2‐cyano‐5‐oxo‐5‐(prop‐2‐yn‐1‐ylamino)pentan‐2‐yl dodecyltrithiocarbonate (COPYDC) and the combination of thiol‐yne click chemistry and thiocarbonylthio chain‐end removal reactions. COPYDC was prepared in good yield and used as an efficient chain transfer agent during the RAFT polymerization of NIPAM. Well‐defined polymers with controlled molar masses (
 = 7500–14,700 g.mol−1) and narrow dispersities (Đ = 1.18–1.26) are thus obtained. Cascade thiol‐yne click reaction at the alkyne α‐chain end and trithiocarbonate removal at the ω‐chain end are successfully achieved using benzyl mercaptan and excess AIBN. The reported method provides a facile and mild route to heterofunctional telechelic RAFT polymers with predictable molar masses and low dispersities. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 3597–3606
Deciphering the promiscuous interactions between intrinsically disordered transactivation domains and the KIX domain
Authors: Huang Yongqi , Gao Meng , Yang Fei , Zhang Lei , Su Zhengding
Published: August 2017

The kinase‐inducible domain interacting (KIX) domain of the transcriptional coactivator CBP protein carries 2 isolated binding sites (designated as the c‐Myb site and the MLL site) and is capable of binding numerous intrinsically disordered transactivation domains (TADs), including c‐Myb and pKID via the c‐Myb site, and MLL, E2A and c‐Jun via the MLL site. In this study we compared the kinetics for binding of various disordered TADs to the KIX domain via computational biophysical analyses. We found that the binding rates are heavily affected by long‐range electrostatic interactions. The basal rate constants for forming the encounter complexes are similar for different KIX binding peptides, favorable electrostatic interactions between the MLL site and the peptides result in greater association rates when peptides bind to the MLL site. FOXO3a and p53 TAD each contains 2 copies of KIX binding motif and each motif interacts with both the MLL site and the c‐Myb site. Our kinetics studies suggest that binding of FOXO3a or p53 TAD to the KIX domain is via a sequential mechanism, where one KIX binding motif binds to the MLL site first and then the other KIX binding motif binds to the c‐Myb site. Considering the promiscuous interactions between FOXO3a and KIX, and p53 TAD and KIX, electrostatic steering simplifies the binding mechanism. This study highlights the importance of long‐range electrostatic interactions in molecular recognition process involving multi‐motif intrinsically disordered proteins and promiscuous interactions.
Interlayer Interaction Effects on the G Modes in Double‐Walled Carbon Nanotubes With Different Electronic Configurations
Authors: Levshov Dmitry I. , Tran Huy‐Nam , Michel Thierry , Cao Thi Thanh , Nguyen Van Chuc , Arenal Raul , Popov Valentin N. , Sauvajol Jean‐Louis , Zahab Ahmed‐Azmi , Paillet Matthieu
Published: August 2017

We present experimental measurements of the features of G band in individual index‐identified free‐standing double‐walled carbon nanotubes. We examine Raman spectra of different electronic configurations of DWNTs, namely: SC@SC, SC@M, M@SC, M@M, and clearly establish that, as in SWNTs, the profile of LO G‐mode of each layer is broad (narrow) when the layer is metallic (semiconducting). The dependence of G‐modes on the diameter and inter‐layer distance in several SC@SC, SC@M, M@SC, M@M index‐identified DWNTs is reported. We find, that, independently of the metallic or semiconducting nature of the layers, the frequencies of LO and TO G‐mode of the inner and outer layers shift significantly with respect to the frequencies of the same modes in the constituent SWNTs.
An exponentially weighted moving average chart based on likelihood‐ratio test for monitoring Weibull mean and variance with subgroups
Authors: Wang Fu‐Kwun , Cheng Xiao‐Bin
Published: August 2017

Monitoring changes in the Weibull mean and variance simultaneously is of interest in quality control. The mean and variance of a Weibull process are determined by its shape and scale parameters. Most studies are focused on monitoring the Weibull scale parameter with fixed shape parameter or the Weibull shape parameter with fixed scale parameter. In this paper, we propose an exponentially weighted moving average chart based on the likelihood‐ratio test and an inverse error function called ELR chart to monitor changes in the Weibull mean and variance simultaneously. The simulation approach is used to derive the average run length. We compare our proposed chart with other existing control charts for 3 cases, including scale parameter changes with fixed shape parameter, shape parameter changes with fixed scale parameter, and both parameters changes. The results show that the ELR chart outperforms the other control charts in terms of average run length in most cases. Two numerical examples are used to illustrate the applications of the proposed control chart.
Bayesian nonparametric areal wombling for small‐scale maps with an application to urinary bladder cancer data from Connecticut
Authors: Guhaniyogi Rajarshi
Published: August 2017

With increasingly abundant spatial data in the form of case counts or rates combined over areal regions (eg, ZIP codes, census tracts, or counties), interest turns to formal identification of difference “boundaries,” or barriers on the map, in addition to the estimated statistical map itself. “Boundary” refers to a border that describes vastly disparate outcomes in the adjacent areal units, perhaps caused by latent risk factors. This article focuses on developing a model‐based statistical tool, equipped to identify difference boundaries in maps with a small number of areal units, also referred to as small‐scale maps. This article proposes a novel and robust nonparametric boundary detection rule based on nonparametric Dirichlet processes, later referred to as Dirichlet process wombling (DPW) rule, by employing Dirichlet process–based mixture models for small‐scale maps. Unlike the recently proposed nonparametric boundary detection rules based on false discovery rates, the DPW rule is free of ad hoc parameters, computationally simple, and readily implementable in freely available software for public health practitioners such as JAGS and OpenBUGS and yet provides statistically interpretable boundary detection in small‐scale wombling. We offer a detailed simulation study and an application of our proposed approach to a urinary bladder cancer incidence rates dataset between 1990 and 2012 in the 8 counties in Connecticut.
An evaluation of constrained randomization for the design and analysis of group‐randomized trials with binary outcomes
Authors: Li Fan , Turner Elizabeth L. , Heagerty Patrick J. , Murray David M. , Vollmer William M. , DeLong Elizabeth R.
Published: August 2017

Group‐randomized trials are randomized studies that allocate intact groups of individuals to different comparison arms. A frequent practical limitation to adopting such research designs is that only a limited number of groups may be available, and therefore, simple randomization is unable to adequately balance multiple group‐level covariates between arms. Therefore, covariate‐based constrained randomization was proposed as an allocation technique to achieve balance. Constrained randomization involves generating a large number of possible allocation schemes, calculating a balance score that assesses covariate imbalance, limiting the randomization space to a prespecified percentage of candidate allocations, and randomly selecting one scheme to implement. When the outcome is binary, a number of statistical issues arise regarding the potential advantages of such designs in making inference. In particular, properties found for continuous outcomes may not directly apply, and additional variations on statistical tests are available. Motivated by two recent trials, we conduct a series of Monte Carlo simulations to evaluate the statistical properties of model‐based and randomization‐based tests under both simple and constrained randomization designs, with varying degrees of analysis‐based covariate adjustment. Our results indicate that constrained randomization improves the power of the linearizationF‐test, the KC‐corrected GEEt‐test (Kauermann and Carroll, 2001, Journal of the American Statistical Association 96, 1387‐1396), and two permutation tests when the prognostic group‐level variables are controlled for in the analysis and the size of randomization space is reasonably small. We also demonstrate that constrained randomization reduces power loss from redundant analysis‐based adjustment for non‐prognostic covariates. Design considerations such as the choice of the balance metric and the size of randomization space are discussed.
Links between causal effects and causal association for surrogacy evaluation in a gaussian setting
Authors: Conlon Anna , Taylor Jeremy , Li Yun , Diaz‐Ordaz Karla , Elliott Michael
Published: August 2017

Two paradigms for the evaluation of surrogate markers in randomized clinical trials have been proposed: the causal effects paradigm and the causal association paradigm. Each of these paradigms rely on assumptions that must be made to proceed with estimation and to validate a candidate surrogate marker (S) for the true outcome of interest (T). We consider the setting in which S and T are Gaussian and are generated from structural models that include an unobserved confounder. Under the assumed structural models, we relate the quantities used to evaluate surrogacy within both the causal effects and causal association frameworks. We review some of the common assumptions made to aid in estimating these quantities and show that assumptions made within one framework can imply strong assumptions within the alternative framework. We demonstrate that there is a similarity, but not exact correspondence between the quantities used to evaluate surrogacy within each framework, and show that the conditions for identifiability of the surrogacy parameters are different from the conditions, which lead to a correspondence of these quantities.
Facet Engineered Interface Design of Plasmonic Metal and Cocatalyst on BiOCl Nanoplates for Enhanced Visible Photocatalytic Oxygen Evolution
Authors: Bai Lijie , Ye Fan , Li Luna , Lu Jingjing , Zhong Shuxian , Bai Song
Published: August 2017

Integration of plasmonic metal and cocatalyst with semiconductor is a promising approach to simultaneously optimize the generation, transfer, and consumption of photoinduced charge carriers for high‐performance photocatalysis. The photocatalytic activities of the designed hybrid structures are greatly determined by the efficiencies of charge transfer across the interfaces between different components. In this paper, interface design of Ag‐BiOCl‐PdOx hybrid photocatalysts is demonstrated based on the choice of suitable BiOCl facets in depositing plasmonic Ag and PdOx cocatalyst, respectively. It is found that the selective deposition of Ag and PdOx on BiOCl(110) planes realizes the superior photocatalytic activity in O2 evolution compared with the samples with other Ag and PdOx deposition locations. The reason was the superior hole transfer abilities of Ag‐(110)BiOCl and BiOCl(110)‐PdOx interfaces in comparison with those of Ag‐(001)BiOCl and BiOCl(001)‐PdOx interfaces. Two effects are proposed to contribute to this enhancement: (1) stronger electronic coupling at the BiOCl(110)‐based interfaces resulted from the thinner contact barrier layer and (2) the shortest average hole diffuse distance realized by Ag and PdOx on BiOCl(110) planes. This work represents a step toward the interface design of high‐performance photocatalyst through facet engineering.
Effect of mixing methods of nano silica on properties of recycled aggregate concrete
Authors: Shaikh Faiz , Chavda Vimal , Minhaj Naji , Arel Hasan S.
Published: August 2017

The effect of presoaking of recycled coarse aggregate (RCA) in nano silica (NS) solution on the properties of recycled aggregates concrete is compared with the direct mixing of NS in concrete. In this study, four series of concrete are considered. The first and second series are control series containing 100% natural coarse aggregate (NCA) and 100% RCA, respectively. The third and fourth series are similar to the second series in every aspect except that 2 wt% NS is added through direct mixing in concrete and presoaking of RCA in 2 wt% NS solution of 24 hr, respectively. Results show that the measured 28‐day compressive strength of recycled aggregate concrete containing presoaked RCA is higher than that containing direct mixing of NS in concrete. The volume of permeable voids, water sorptivity, and chloride ion penetration measured after 28 days curing is also reduced in recycled aggregate concrete containing presoaked RCA in NS solution than that containing direct mixing of NS in concrete. The total porosity of mortar adjacent to presoaked RCA is also found to be significantly lower than the same, where NS is mixed directly. The concentration of pores in the matrix adjacent to presoaked RCA is also shifted to medium capillary pores from the large capillary pores of matrix adjacent to RCA containing no NS. The volume of medium capillary pores reduced significantly in the matrix adjacent to presoaked RCA compared to the same, where NS is mixed directly. The scanning electron microscopic image analysis also supports this observation.