bluuebunny/crossref_metadata_2025 huggingface dataset:
Community Patterns and Environmental Associations for Pelagic Fishes in a Highly Modified Estuary
Authors: Castillo Gonzalo C. , Damon Lauren J. , Hobbs James A.
Published: October 2018

Understanding how natural and human-induced processes interact to influence ecosystem responses is essential for their effective management and conservation. Long-term environmental degradation of the upper San Francisco Estuary, California, has resulted in numerous species declines. In this study, we used pelagic fish monitoring and hydrodynamic data during winter–spring 2002–2014 to evaluate how natural and human-induced environmental changes in the upper San Francisco Estuary may have influenced the distribution, abundance, and community structure of the pelagic fishes. Delta outflow and turbidity tended to decline and salinity tended to increase since the early 2000s. Twelve of the 27 pelagic fish species sampled were introduced, most of which were freshwater-dominant species in highly altered upstream areas. Overall mean relative abundance was similar between native and introduced fishes across all study areas. The upstream distribution of the eight most abundant pelagic fishes was generally associated with their salinity habitat components. Among these species, the Delta Smelt Hypomesus transpacificus and the introduced Threadfin Shad Dorosoma petenense had the highest rates of population decline over the period 2002–2014 and the largest relative increase in salinity predicted in their habitats due to hydrological alteration. Community structure was significantly related to abiotic factors (water temperature, salinity, and turbidity) and spatiotemporal variation (longitude and month), which accounted for 30–33% of the variation. Low to intermediate outflows due to droughts and water diversions since the early 2000s likely interacted synergistically with multiple factors, decreasing the abundance of several pelagic species. Management actions linking ecologic, hydrologic, and geomorphic processes with multiple stressors could help to reverse the long-term decline of Delta Smelt and other threatened and endangered fishes in the San Francisco Estuary.
Genotype‐phenotype relations for the Parkinson's disease genes SNCA, LRRK2, VPS35: MDSGene systematic review
Authors: Trinh Joanne , Zeldenrust Florentine M.J. , Huang Jana , Kasten Meike , Schaake Susen , Petkovic Sonja , Madoev Harutyun , Grünewald Anne , Almuammar Shahad , König Inke R. , Lill Christina M. , Lohmann Katja , Klein Christine , Marras Connie
Published: October 2018

This comprehensive MDSGene review is devoted to the three autosomal‐dominant PD forms: PARK‐SNCA, PARK‐LRRK2, and PARK‐VPS35. It follows MDSGene's standardized data extraction protocol, screened a total of 2,972 citations, and is based on fully curated phenotypic and genotypic data on 937 patients with dominantly inherited PD attributed to 44 different mutations in SNCA, LRRK2, or VPS35. All of these data are also available in an easily searchable online database (www.mdsgene.org), which additionally provides descriptive summary statistics on phenotypic and genetic data. Despite the high degree of missingness of phenotypic features and unsystematic reporting of genotype data in the original literature, the present review recapitulates many of the previously described findings including later onset of disease (median age at onset: ∼49 years) compared to recessive forms of PD of an overall excellent treatment response. Our systematic review validates previous reports showing that SNCA mutation carriers have a younger age at onset compared to LRRK2 and VPS35 (P < 0.001). SNCA mutation carriers often have additional psychiatric symptoms, and although not exclusive to only LRRK2 or VPS35 mutation carriers, LRRK2 mutation carriers have a typical form of PD, and, lastly, VPS35 mutation carriers have good response to l‐dopa. © 2018 International Parkinson and Movement Disorder Society
Perilla Oil Supplementation Improves Hypertriglyceridemia and Gut Dysbiosis in Diabetic KKAy Mice
Authors: Wang Feng , Zhu Hangju , Hu Mingyuan , Wang Jing , Xia Hui , Yang Xian , Yang Ligang , Sun Guiju
Published: October 2018

Scope

The aim of this study is to examine whether perilla oil supplementation improves glucolipid metabolism and modulates gut microbiota in diabetic KKAy mice.

Methods and results

The successfully established diabetic KKAy mice are randomized into four groups: diabetic model (DM), low‐dose perilla oil (LPO), middle‐dose perilla oil (MPO), and high‐dose perilla oil (HPO). C57BL/6J mice are fed a chow diet as normal control (NC). At the end of 12 weeks, mice are euthanized and glucolipid indications are analyzed. Gut microbiota analysis is carried out based on the sequencing results on V4 region of 16S rRNA. Although serum glucose, insulin, total cholesterol, low‐density lipoprotein cholesterol, high‐density lipoprotein cholesterol, abundance‐based coverage estimator, and shannon are unchanged, serum triglyceride significantly decreases in LPO compared with DM. The histopathological changes of hepatocellular macrovesicular steatosis and adipocyte hypertrophy are ameliorated by perilla oil supplementation. Blautia is significantly decreased in LPO, MPO, and HPO, compared with DM. Nonmetric multidimensional scaling analysis shows NC and LPO are relatively coherent.

Conclusion

These findings indicate that dietary supplementation with perilla oil can improve hypertriglyceridemia and gut dysbiosis in diabetic KKAy mice, which can be associated with potential benefits to human health.
Invertibility of the dual energy x‐ray data transform
Authors: Alvarez Robert E.
Published: October 2018

Purpose

The Alvarez–Macovski method extracts the x‐ray energy‐dependent information by expanding the attenuation coefficient as a linear combination of functions of energy multiplied by basis set coefficients. Since the basis functions are known a priori, the coefficients represent all the energy‐dependent information. The method then computes the line integrals of these coefficients, summarized as a vector A, from measurements with multiple x‐ray spectra, summarized as a vector L. The purpose of this paper is to determine the factors that affect the invertibility of the L(A) transformation with a two function basis set and two spectral measurements, the dual energy transformation.

Methods

A general invertibility theorem is applied that requires testing for zero values of the Jacobian of the transformation in its input domain. General conditions for invertibility are proved. It is shown that the generalized A vector noise variance is proportional to the generalized measurement noise variance divided by the square of the Jacobian. The relationship between the zero Jacobian values and ambiguous sets of A vector points with the same L values is determined. The effect of zero Jacobian values on an iterative algorithm that inverts L(A) is simulated.

Results

The choice of a particular valid basis set does not affect invertibility. Nonoverlapping measurement spectra such as those from photon counting detectors with perfect pulse height analysis are invertible. The widely used x‐ray tube spectra with different voltages are shown to be invertible. Spectra with the same maximum energy, such as those from layered detectors, approach noninvertibility with small absolute value Jacobian for large object thicknesses. The zero Jacobian values fall on curves in A vector space that, except for a simple artificial case, are close to but not exactly straight lines. With noninvertible spectra, pairs of ambiguous points are located on opposite sides of the zero Jacobian curve. The iterative algorithm has large convergence errors near zero Jacobian curves and converges to the closest ambiguous point to the initial estimate for other points.

Conclusion

The invertibility of dual energy systems is determined by the presence of zero values of the Jacobian of the dual x‐ray energy data transformation L(A) in the input domain.
Frequency‐modulated SSFP with radial sampling and subspace reconstruction: A time‐efficient alternative to phase‐cycled bSSFP
Authors: Roeloffs Volkert , Rosenzweig Sebastian , Holme H. Christian M. , Uecker Martin , Frahm Jens
Published: October 2018

Purpose

A novel subspace‐based reconstruction method for frequency‐modulated balanced steady‐state free precession (fmSSFP) MRI is presented. In this work, suitable data acquisition schemes, subspace sizes, and efficiencies for banding removal are investigated.

Theory and Methods

By combining a fmSSFP MRI sequence with a 3D stack‐of‐stars trajectory, scan efficiency is maximized as spectral information is obtained without intermediate preparation phases. A memory‐efficient reconstruction routine is implemented by introducing the low‐frequency Fourier transform as a subspace which allows for the formulation of a convex reconstruction problem. The removal of banding artifacts is investigated by comparing the proposed acquisition and reconstruction technique to phase‐cycled bSSFP MRI. Aliasing properties of different undersampling schemes are analyzed and water/fat separation is demonstrated by reweighting the reconstructed subspace coefficients to generate virtual spectral responses in a post‐processing step.

Results

A simple root‐of‐sum‐of‐squares combination of the reconstructed subspace coefficients yields high‐SNR images with the characteristic bSSFP contrast but without banding artifacts. Compared to Golden‐Angle trajectories, turn‐based sampling schemes were superior in minimizing aliasing across reconstructed subspace coefficients. Water/fat separated images of the human knee were obtained by reweighting subspace coefficients.

Conclusions

The novel subspace‐based fmSSFP MRI technique emerges as a time‐efficient alternative to phase‐cycled bSFFP. The method does not need intermediate preparation phases, offers high SNR and avoids banding artifacts. Reweighting of the reconstructed subspace coefficients allows for generating virtual spectral responses with applications to water/fat separation.
Visualizing artery‐specific blood flow patterns above the circle of Willis with vessel‐encoded arterial spin labeling
Authors: Okell Thomas W. , Garcia Meritxell , Chappell Michael A. , Byrne James V. , Jezzard Peter
Published: October 2018

Purpose

To establish the feasibility of using vessel‐encoded pseudocontinuous arterial spin labeling (VEPCASL) for noninvasive vascular territory imaging (VTI) and artery‐specific dynamic angiography of a large number of arterial branches above the circle of Willis within a clinically feasible scan time.

Methods

3D time‐of‐flight angiography was used to select a labeling plane and establish 7 pairs of encoding cycles. These were used for VEPCASL VTI and dynamic 2D angiography (8 min and 3 min acquisition times, respectively) in healthy volunteers, allowing the separation of signals arising from 13 arterial branches (including extracranial arteries) in postprocessing. To demonstrate the clinical potential of this approach, VEPCASL angiography was also applied in 5 patients with brain arteriovenous malformation (AVM).

Results

In healthy volunteers, the artery‐specific filling of the vascular tree and resulting perfusion territories were well depicted. SNRs were approximately 5 times higher than those achievable with single‐artery selective methods. Blood supply to the AVMs was well visualized in all cases, showing the main feeding arteries and venous drainage.

Conclusions

VEPCASL is a highly efficient method for both VTI and dynamic angiography of a large number of arterial branches, providing a comprehensive picture of vascular flow patterns and the effect on downstream tissue perfusion within an acceptable scan time. Automation of labeling plane and vessel‐encoding selection would improve robustness and efficiency, and further refinement could allow quantitative blood flow measurements to be obtained. This technique shows promise for visualizing the blood supply to lesions and collateral flow patterns.
Cryogen‐free dissolution dynamic nuclear polarization polarizer operating at 3.35 T, 6.70 T, and 10.1 T
Authors: Ardenkjær‐Larsen Jan Henrik , Bowen Sean , Petersen Jan Raagaard , Rybalko Oleksandr , Vinding Mads Sloth , Ullisch Marcus , Nielsen Niels Chr.
Published: October 2018

Purpose

A novel dissolution dynamic nuclear polarization (dDNP) polarizer platform is presented. The polarizer meets a number of key requirements for in vitro, preclinical, and clinical applications.

Method

It uses no liquid cryogens, operates in continuous mode, accommodates a wide range of sample sizes up to and including those required for human studies, and is fully automated.

Results

It offers a wide operational window both in terms of magnetic field, up to 10.1 T, and temperature, from room temperature down to 1.3 K. The polarizer delivers a 13C liquid state polarization for [1‐13C]pyruvate of 70%. The build‐up time constant in the solid state is approximately 1200 s (20 minutes), allowing a sample throughput of at least one sample per hour including sample loading and dissolution.

Conclusion

We confirm the previously reported strong field dependence in the range 3.35 to 6.7 T, but see no further increase in polarization when increasing the magnetic field strength to 10.1 T for [1‐13C]pyruvate and trityl. Using a custom dry magnet, cold head and recondensing, closed‐cycle cooling system, combined with a modular DNP probe, and automation and fluid handling systems, we have designed a unique dDNP system with unrivalled flexibility and performance.
Perfusion of the placenta assessed using arterial spin labeling and ferumoxytol dynamic contrast enhanced magnetic resonance imaging in the rhesus macaque
Authors: Ludwig Kai D. , Fain Sean B. , Nguyen Sydney M. , Golos Thaddeus G. , Reeder Scott B. , Bird Ian M. , Shah Dinesh M. , Wieben Oliver E. , Johnson Kevin M.
Published: October 2018

Purpose

To investigate the correspondence between arterial spin labeling (ASL) flow‐sensitive alternating inversion recovery (FAIR) and ferumoxytol DCE MRI for the assessment of placental intervillous perfusion.

Methods

Ten pregnant macaques in late second trimester were imaged at 3 T using a 2D ASL FAIR, with and without outer‐volume saturation pulses used to control the bolus width, and a 3D ferumoxytol DCE‐MRI acquisition. The ASL tagged/control pairs were averaged, subtracted, and normalized to create perfusion ratio maps. Contrast arrival time and uptake slope were estimated by fitting the DCE data to a sigmoid function. Macaques (N = 4) received interleukin‐1β to induce inflammation and disrupt perfusion.

Results

The FAIR tag modification with outer‐volume saturation reduced the median ASL ratio percentage compared with conventional FAIR (0.64% ± 1.42% versus 0.71% ± 2.00%; P < .05). Extended ferumoxytol arrival times (34 ± 25 seconds) were observed across the placenta. No significant DCE signal change was measured in fetal tissue (0.6% ± 3.0%; P = .52) or amniotic fluid (1.9% ± 8.8%; P = .59). High ASL ratio was significantly correlated with early arrival time and high uptake slope (P < .05), but ASL signal was not above noise in late‐DCE‐enhancing regions. No significant differences were observed in perfusion measurements between the interleukin‐1β and controls (P > .05).

Conclusion

The ASL‐FAIR and ferumoxytol DCE‐MRI methods are feasible to detect early blood delivery to the macaque placenta. Outer volume saturation reduced the high macrovascular ASL signal. Interleukin‐1β exposure did not alter placental intervillous perfusion. An endogenous‐labeling perfusion technique is limited due to extended transit times for flow within the placenta beyond the immediate vicinity of the maternal spiral arteries.
Exploring the Potential Effectiveness of Combining Optimal Nutrition With Electrical Stimulation to Maintain Muscle Health in Critical Illness: A Narrative Review
Authors: Parry Selina M. , Chapple Lee‐anne S. , Mourtzakis Marina
Published: October 2018

Muscle wasting occurs rapidly within days of an admission to the intensive care unit (ICU). Concomitant muscle weakness and impaired physical functioning can ensue, with lasting effects well after hospital discharge. Early physical rehabilitation is a promising intervention to minimize muscle weakness and physical dysfunction. However, there is an often a delay in commencing active functional exercises (such as sitting on the edge of bed, standing and mobilizing) due to sedation, patient alertness, and impaired ability to cooperate in the initial days of ICU admission. Therefore, there is high interest in being able to intervene early through nonvolitional exercise strategies such as electrical muscle stimulation (EMS).

Muscle health characterized as the composite of muscle quantity, as well as functional and metabolic integrity, may be potentially maintained when optimal nutrition therapy is provided in complement with early physical rehabilitation in critically ill patients; however, the type, dosage, and timing of these interventions are unclear.

This article explores the potential role of nutrition and EMS in maintaining muscle health in critical illness. Within this article, we will evaluate fundamental concepts of muscle wasting and evaluate the effects of EMS, as well as the effects of nutrition therapy on muscle health and the clinical and functional outcomes in critically ill patients. We will also highlight current research gaps in order to advance the field forward in this important area.
Diet‐Induced Paternal Obesity Impairs Cognitive Function in Offspring by Mediating Epigenetic Modifications in Spermatozoa
Authors: Zhou Yin , Zhu Hong , Wu Hai‐Yan , Jin Lu‐Yang , Chen Bin , Pang Hai‐Yan , Ming Zhen‐Hua , Cheng Yi , Zhou Cheng‐Liang , Guo Meng‐Xi , Huang Yi‐Ting , Yu Dan‐Qing , Sheng Jian‐Zhong , Huang He‐Feng
Published: October 2018

Objective

This study aimed to determine the effects of diet‐induced paternal obesity on cognitive function in mice offspring.

Methods

Male mice (F0) were randomized to receive either a control diet (10 kcal% fat) or a high‐fat diet (HFD; 60 kcal% fat) for 10 weeks before being mated with normal females to generate F1 offspring. Male F1 offspring were mated with normal females to generate F2 offspring. Behavioral tests were used to assess cognitive functions in F1 and F2 offspring. Reduced representation bisulfite sequencing was used to the explore mechanisms of epigenetic inheritance.

Results

HFD‐induced paternal obesity resulted in cognitive impairments in F1 offspring, potentially due, at least in part, to increased methylation of the BDNF gene promoter, which was inherited from F0 spermatozoa. BDNF/tyrosine receptor kinase B signaling was associated with cognitive impairments in HFD‐fed F1 offspring. However, there were no significant changes in F2 offspring.

Conclusions

The findings provide evidence of intergenerational effects of paternal obesity on cognitive function in offspring occurring via epigenetic spermatozoan modifications.
Impact of Food Ingredients (Aspartame, Stevia, Prebiotic Oligofructose) on Fertility and Reproductive Outcomes in Obese Rats
Authors: Cho Nicole A. , Klancic Teja , Nettleton Jodi E. , Paul Heather A. , Reimer Raylene A.
Published: October 2018

Objective

This study aimed to investigate the interaction between obesity, low‐calorie sweeteners, and prebiotic oligofructose on reproductive parameters in rats.

Methods

Data were derived from two separate studies of female Sprague‐Dawley rats with (1) Lean (n = 24), (2) Obese (n = 27), (3) Obese+Aspartame (n = 14), (4) Obese+Stevia (n = 15), and (5) Obese+Prebiotic (n = 15) groups. Obesity was induced with a high‐fat/high‐sucrose diet prior to pregnancy. In one study, human‐approved doses of aspartame (5‐7 mg/kg/d) and stevia (2‐3 mg/kg/d) in drinking water were examined, and in the second, 10% prebiotics (oligofructose) in the diet was examined. Reproductive parameters, including fertility, pregnancy, and delivery indexes, were analyzed.

Results

Obesity significantly reduced pregnancy index in Obese dams (60.7% successful pregnancies) compared with lean (100%). Obesity also reduced the number of pups born alive and pup survival percentage compared with those of Lean dams (P < 0.001). Only 53.3% of rats were able to conceive in the Obese+Stevia group, but if rats did become pregnant, they had 100% pregnancy and delivery index. While prebiotic administration rescued the pregnancy index, it could not remediate pup survival percentage (P = 0.025) in Obese dams.

Conclusions

Both obesity status and dietary ingredients affect the ability to conceive. Future rigorously controlled studies designed to examine reproductive outcomes in depth are needed to confirm these findings.
Dosing Exercise: Is More Really Better for Obesity‐Related Outcomes?
Authors: Malin Steven K.
Published: October 2018

See accompanying article, pg. 1696.
LGR5 promotes tumorigenicity and invasion of glioblastoma stem‐like cells and is a potential therapeutic target for a subset of glioblastoma patients
Authors: Xie Yuan , Sundström Anders , Maturi Naga P , Tan E‐Jean , Marinescu Voichita D , Jarvius Malin , Tirfing Malin , Jin Chuan , Chen Lei , Essand Magnus , Swartling Fredrik J , Nelander Sven , Jiang Yiwen , Uhrbom Lene
Published: October 2018

Glioblastoma (GBM) is the most common and lethal primary malignant brain tumor which lacks efficient treatment and predictive biomarkers. Expression of the epithelial stem cell marker Leucine‐rich repeat‐containing G‐protein coupled receptor 5 (LGR5) has been described in GBM, but its functional role has not been conclusively elucidated. Here, we have investigated the role of LGR5 in a large repository of patient‐derived GBM stem cell (GSC) cultures. The consequences of LGR5 overexpression or depletion have been analyzed using in vitro and in vivo methods, which showed that, among those with highest LGR5 expression (LGR5high), there were two phenotypically distinct groups: one that was dependent on LGR5 for its malignant properties and another that was unaffected by changes in LGR5 expression. The LGR5‐responding cultures could be identified by their significantly higher self‐renewal capacity as measured by extreme limiting dilution assay (ELDA), and these LGR5high‐ELDAhigh cultures were also significantly more malignant and invasive compared to the LGR5high‐ELDAlow cultures. This showed that LGR5 expression alone would not be a strict marker of LGR5 responsiveness. In a search for additional biomarkers, we identified LPAR4, CCND2, and OLIG2 that were significantly upregulated in LGR5‐responsive GSC cultures, and we found that OLIG2 together with LGR5 were predictive of GSC radiation and drug response. Overall, we show that LGR5 regulates the malignant phenotype in a subset of patient‐derived GSC cultures, which supports its potential as a predictive GBM biomarker. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
High‐performance bio‐based poly(lactic acid)/natural rubber/epoxidized natural rubber blends: effect of epoxidized natural rubber on microstructure, toughness and static and dynamic mechanical properties
Authors: Nematollahi Mahsa , Jalali‐Arani Azam , Modarress Hamid
Published: October 2018

Attempts have been made to prepare high‐performance bio‐based blends through blending of poly(lactic acid) (PLA) with natural rubber (NR) in the presence of epoxidized natural rubber (ENR) as a compatibilizer. The prepared samples were characterized using differential scanning calorimetry, measuring the tensile properties and impact resistance, scanning electron microscopy, Fourier transform infrared (FTIR) spectroscopy and dynamic mechanical analysis (DMTA). Morphological studies revealed a matrix‐dispersed morphology for all blends, in which the average droplet size significantly decreased with the use of ENR. The elongation at break and impact strength of the blend containing 3 wt% ENR were 45 and 16 times those of neat PLA, respectively. These values are significantly higher than those previously reported for various simple and dynamically vulcanized rubber‐toughened PLAs. The influence of ENR on compatibility was confirmed by rheological tests, FTIR spectra and DMTA. DMTA also showed a marked increase in elastic modulus for the blend in the presence of 3 wt% ENR. The tensile properties and impact resistance were directly dependent on the ENR content and rubber droplet size. © 2018 Society of Chemical Industry
Porins and Amyloids are Coded by Similar Sequence Motifs
Authors: Villain Etienne , Nikekhin Aleksei A. , Kajava Andrey V.
Published: October 2018

The relationship between amino acid sequences of the β‐hairpin structures and amyloidogenic β‐arcade‐forming motifs are of special interest because, similar to amyloid fibrils, most of the β‐hairpin repeat (BHR) structures have the so‐called cross‐β arrangement. Moreover, β‐hairpin is considered as a probable intermediate structure in amyloidogenesis. In this work, a bioinformatics sequence analysis of the known BHR structures is performed in search of amylodogenic motifs able to form β‐arcade fibrils. The analysis shows that the occurrence of the predicted β‐arcade motifs in the BHR regions is very different depending on the BHR structural fold, cellular localization, and phylogeny. One of the most striking observations is the high level of sequence similarity between the BHRs of membranous porins and β‐arcade motifs. This sequence similarity provides additional evidence that the structure of the membranous porins and annular amyloid oligomers may bear a resemblance. Moreover, these results explain how some amyloidogenic sequence can fold in either the ring‐like shape oligomers or elongated amyloid fibrils. It has been also found that potentially lethal amyloidogenic β‐arcade motifs are absent in the elongated BHR structures of intracellular eukaryotic proteins. It allows to hypothesize that, in this case, the selective evolutionary pressure acts against aggregation.
Investigation of degradation pathways of poly(semiperfluoroalkyl methacrylate) thin films induced by electron‐beam irradiation
Authors: Jung Seok‐Heon , Chuluunbandi Khajidkhand , Kim Youngtae , Son Jongchan , Oh Hyun‐Taek , Lee Jin Hyun , Lee Jin‐Kyun , Beom‐Hoan O
Published: October 2018

In this article, we report the results of high‐energy electron beam (e‐beam) irradiation of polymer thin films made of poly(semiperfluoroalkyl methacrylate)s (PRFMAs) and propose plausible chemical reactions that may cause their solubility to change in fluorous liquids. It was observed that the polymer films were converted to a more soluble state under low exposure doses of e‐beam, possibly due to main‐chain scission. However, the films became insoluble with higher doses of e‐beam. Three hypotheses were proposed to explain the reduction in solubility, and we used data from Fourier transform infrared spectroscopy, X‐ray photoelectron spectroscopy, mass spectrometry (MS), and nanoindentation to eliminate the less probable hypotheses. The results derived from e‐beam‐irradiated thin films of three PRFMAs showed that the radical‐related Norrish Type I and II pathways may not be the main decomposition routes. The data also suggested that sufficient scission reactions of the perfluorooctyl moieties of PRFMAs do not occur by e‐beam. We therefore assumed that the decrease in solubility of the fluorinated polymers results from intermolecular crosslinking reactions between the free radicals and reactive moieties generated on the perfluorooctyl groups by the e‐beam. The unique imaging mechanism of PRFMAs may be developed further to synthesize radiation‐sensitive materials working under e‐beam and extreme ultraviolet (λ = 13.5 nm) lithography conditions for advanced patterning applications. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 2672–2680
PbS Nanoparticles for Ultrashort Pulse Generation in Optical Communication Region
Authors: Zhang Ying , Li Xiaohui , Qyyum Abdul , Feng Tianci , Guo Penglai , Jiang Jie , Zheng Hairong
Published: October 2018

Lead sulfide (PbS) has attracted great attention due to its unique electronic, optical, and chemical properties. In particular, the narrow bandgap of PbS (≈0.37 eV) makes it very suitable for the ultrafast application in optical communication or even longer wavelength region. In this work, PbS nanoparticles' (NPs) dispersion without any polymer is utilized as saturable absorber (SA) to generate ultrafast pulse in a fiber ring laser for the first time. The characterization and nonlinear properties of PbS NPs are investigated experimentally. PbS NPs are deposited on a flange to compose a nonlinear device. The nonlinear absorption is measured by a power‐dependent method with a modulation depth of 12.2%. Most importantly, PbS NPs can be applied for the ultrafast photonics applications. A compact mode‐locked fiber laser with 1.01 ps pulse duration, 2.93 nm spectral width, and 3.97 MHz repetition rate at 1533 nm is successfully achieved with long time stability. The output laser is detected with a good stability for more than 1 month without any degradation. This work can demonstrate that the PbS NPs' dispersion is indeed a new and excellent photonics material for SA photonics, photoconductive detection, and optical modulator, etc.
Belonging in Brexit Britain: Central and Eastern European 1.5 generation young people's experiences
Authors: Tyrrell Naomi , Sime Daniela , Kelly Claire , McMellon Christina
Published: October 2018

In this paper, we examine the experiences of young people born in Central and Eastern Europe (CEE) who are part of the 1.5 migrant generation living in “Brexit Britain.” We focus on two key themes: (a) young people's feelings of belonging to Britain, their countries of birth and Europe, and the ways in which these have been impacted by the EU Referendum result; (b) young people's future plans, in an intergenerational context, with particular regard to their feelings of belonging and the ruptures of migration and Brexit. Britain's decision to leave the EU caused uncertainty for CEE 1.5 generation young people at a time when many of them were consciously reflecting on their beings, becomings, and belongings. The majority of young people asserted a sense of belonging to Britain whilst simultaneously feeling a sense of “in‐between‐ness.” Many young people wanted to remain living in Britain, at least in the short term, and felt a sense of belonging to Britain. Our focus on the potential intergenerational impact of Brexit suggests that CEE young people and parents may view possibilities for the future differently; we examine some of the key reasons for these differences from the young people's perspectives.
Spatial segregation and migration in the city of Athens: Investigating the evolution of urban socio‐spatial immigrant structures
Authors: Panori Anastasia , Psycharis Yannis , Ballas Dimitris
Published: October 2018

Migration has long had an impact on spatial segregation within the metropolitan area of Athens. This process has also been affected by local economic restructuring mechanisms, which, in recent years, have evolved within the context of the 2008 economic crisis. This study attempts to shed light on the evolution of the spatial segregation of immigrants within the metropolitan area of Athens, during a period of a rapid urban transformation, using data from the last two census waves (2001 and 2011). Given that previous evidence indicates both vertical segregation in the immigrant labour market structure and diffused immigrant settlements, the work presented here investigates the ways in which urban migrant structures have evolved through local economic restructuring processes, as well as throughout space. The study presents a set of quantitative urban segregation indicators, covering the aspects of evenness, exposure, concentration, and centralisation. It also captures the most significant occupational changes between different migrant‐status groups (non‐EU and EU immigrants), during a crucial period for Athens. Evidence indicates that there has been an overall raise in immigrant settlement segregation, accompanied by an increased centralisation trend. Moreover, the urban transformation through economic restructuring that took place in Athens, following the general EU trend towards a knowledge‐based economic model, has altered the immigrant labour market structure, leading to vertical segregation patterns, driven by professionalisation.
Migration as an opportunity to register changing partisan loyalty in the United States
Authors: Cho Wendy K. Tam , Gimpel James G. , Hui Iris S.
Published: October 2018

We explore the connection between residential migration choices and political party identification by movers who change their political party registration. We find that an impressive number of migrants choose neighbourhoods that favor their new party of registration. The association between the party change of the migrant and the balance of local partisanship in their new neighborhood cannot be accounted for by a process of neighbourhood socialisation because the move is too recent for socialisation pressures to have operated. It is more likely that the migrant's political transition occurred well before the relocation and shaped the destination search. Relocation offered an opportunity to mark a previously transformed partisan preference on the voter rolls. In this sense, partisan identification is stable, but observing any large subset of migrants may make it appear unhinged, as this group collectively takes its opportunity to officially disclose their change in political party loyalty when they have a chance to relocate and must reregister.
Ab Initio Studies on Structural, Mechanical, Electronic, Magnetic, and Thermoelectric Transport Properties of CeCo4P12
Authors: Yadav Priya , Nautiyal Shashank , Verma Udai Pratap
Published: October 2018

The structural, mechanical, electronic, magnetic, and thermoelectric transport properties of Ce‐filled skutterudite CeCo4P12 have been studied for the first time by using the full potential linearized augmented plane wave (FP‐LAPW) method. The exchange‐correlation potential is described by the generalized gradient approximation (GGA) as well as GGA + U (where U is the Hubbard parameter). The structural parameters and the elastic constants have been obtained using PBEsol‐GGA, local spin density approximation (LSDA), and PBE‐GGA functional. The obtained lattice constant using PBEsol‐GGA functional is in excellent agreement with the experimental results, therefore, the rest of the results are obtained using PBEsol‐GGA functional. Further refinements in the electronic properties were obtained by adding spin‐orbit coupling (SOC). The Hubbard parameter for Ce atom has a very small effect on the magnetic moment while Co atom has a significant effect on the magnetic moment of CeCo4P12. In its ferromagnetic behavior, the main contribution is due to Ce‐atoms. The reported results show that CeCo4P12 is metallic in nature, mechanically stable, and elastically brittle. The thermoelectric transport figure of merit at room temperature is larger than the reported values for the Ce‐filled skutterudite compounds CeRu4Sb12 and CeFe4Sb12. This indicates that CeCo4P12 exhibits better thermoelectric properties at room temperature as compared to the other Ce‐filled skutterudites.
Regular Network of Misfit Dislocations at the BaZr0.8Y0.2O3−x/NdGaO3 Interface and Its Role in Proton Conductivity
Authors: Felici Roberto , Aruta Carmela , Yang Nan , Zarotti Francesca , Foglietti Vittorio , Cantoni Claudia , Tebano Antonello , Carlà Francesco , Balestrino Giuseppe
Published: October 2018

The interface between mismatched perovskite oxides presents novel physical and chemical features of interest for the development of engineered materials with tailored properties. In this article, we report on the presence and properties of a regular network of misfit dislocations (MDs), which self‐assembles at the interface between a thin film of the proton conductor BaZr0.8Y0.2O2.9 and the substrate, the (110) oriented NdGaO3 wide‐gap insulator. The conductivity properties of this system strongly depend on the atmosphere at which a thermal annealing is carried out. Namely, a conductivity increase is observed after annealing at 450 °C in wet atmosphere. An annealing in dry environment at the same temperature brings back the conductivity to its pristine value. X‐ray diffraction measurements show a strong increase of the strain field associated with the dislocation network, after annealing in wet atmosphere, suggesting that hydroxyl groups mostly accumulate in the cores of the interface MDs rather than in the bulk of the BaZr0.8Y0.2O2.9 thin film. A further annealing in dry environment allows to recover the initial value of the strain field. The reported data indicate a strong involvement of the interface MDs in the transport properties of perovskite oxide interfaces.
Research Progress in Multielectron Reactions in Polyanionic Materials for Sodium‐Ion Batteries
Authors: Liu Rui , Liang Ziteng , Gong Zhengliang , Yang Yong
Published: October 2018

Realizing multielectron reactions in electrodes is crucial for improving the capacity and energy density of batteries. Polyanion‐type compounds are suitable for exploring multielectron reactions due to their robust frameworks and structural diversity. This paper reviews the recent research progress on the study of multielectron reactions in Na‐based polyanion compounds. The versatile polyanions are classified by transition metals (V, Mn, Fe, Ti, Cr, and Co). Both experimental efforts and theoretical calculations are analyzed and summarized, with a special focus on the reversibility, stability, and corresponding structural evolutions during the multielectron reactions. The challenges and opportunities of exploring polyanions with reversible and stable multielectron reactions are also discussed.
Improved Light Efficiency in Si Solar Cells by Coating Mesoporous TiO2 and Cu‐Modified Mesoporous TiO2
Authors: Ravuvari Ajay K. , Yechuri Sandeep , Chaitanya Ch , Rajesh Cherukupalli
Published: October 2018

In the present work, an improvement in light‐conversion efficiency by coating spherical particles of mesoporous TiO2 (MT) and copper‐modified mesoporous TiO2 (CMT) on single‐crystalline Si solar PV cell is observed. The studies are carried out by spin coating with different concentrations of MT (0.25 to 1.5%) and CMT (0.25 to 1.0%) particles on bare cells independently and compared with a bare solar cell throughout the work. It is observed that in the case of MT coatings, the conversion efficiency increases initially and reaches a maximum of 9.77% at a coating concentration of 1.0%; thereafter, it decreases with an increase in coating concentration. This decrease in efficiency may be attributed to coagulation of MT particles, whereas in the case of CMT particles the conversion efficiency reached a maximum of 8.85% at 0.5% concentration and decreases thereafter. This study indicates that a higher efficiency can be achieved at lower concentrations of CMT coating compared to MT coatings on a bare solar cell. The increase in efficiency may be attributed to better surface passivation and/or trapping of electrons at the metal sites by Cu in CMT. Recombination lifetime measurements results corroborated that CMT particles show better surface passivation as a result of which there is an increase in efficiency. Diffused reflectance and short‐circuit current ratio versus wavelength studies on MT and CMT also revealed that CMT particles perform better than MT particles.
New Insights into the Biology of Anadromous Dolly Varden in the Canning River, Arctic National Wildlife Refuge, Alaska
Authors: Brown Randy J. , Courtney Michael B. , Seitz Andrew C.
Published: October 2018

Anadromous Dolly Varden Salvelinus malma in northeastern Alaska migrate to sea during the summer to feed but must overwinter in rivers because the sea under ice becomes too cold for salmonids. Flow ceases in rivers during the winter except for a few perennial springs in which all fish congregate. The Canning River is one of the largest rivers in the area with numerous perennial springs that support Dolly Varden during the winter. It also marks the western boundary of the Arctic National Wildlife Refuge as it flows across the coastal plain to the Beaufort Sea. We sought to improve our understanding of habitat use, migration timing, survival, and interdrainage exchange of Dolly Varden in the Canning River to improve management efforts to minimize the environmental impacts of potential hydrocarbon resource development in the area. To achieve these objectives, we deployed 210 radio tags in mature Dolly Varden during 2014 and 2015 and then determined their seasonal locations with aerial surveys of the Canning River and other nearby rivers and with a radio receiver located in the lower Canning River. Dolly Varden spawned and overwintered in several areas of the main stem and in perennial springs in the upper reaches of the drainage. Nonspawning fish occupied similar main‐stem habitats during the winter, but did not migrate into upstream reaches. Migration to sea occurred during a brief period in early to mid‐June, while fish returned to the river in small numbers over the next 3 months. The estimated annual survival of nonspawners (0.62) was significantly greater than that for postspawners (0.34). Survival in freshwater during winter was significantly greater than that in marine environments during the summer for both demographic groups. The interdrainage exchange rate was estimated to be 0.37. These data enhance our understanding of annual cycles of Dolly Varden habitat use, migration, and population dynamics.
Understanding microbial ecology to improve management of drinking water distribution systems
Authors: Douterelo Isabel , Sharpe Rebecca L. , Husband Stewart , Fish Katherine E. , Boxall Joby B.
Published: October 2018

Microorganisms in drinking water distribution systems (DWDS), and in particular the microbial communities that form biofilms on infrastructure surfaces, drive critical processes impacting water quality. This paper reviews knowledge, research approaches, and monitoring methods to consolidate understanding of the microbial ecology of DWDS. The review highlights how microbial characteristics and subsequent behavior can be broadly classified as common or complex. Common behavior relates to the ubiquitous and continual development of biofilms, consistent core communities, and mediated material accumulation. In contrast, the complex aspect relates to the shape, structure, and composition of the microbiome, defined by site‐specific properties such as supplied source water, pipe material, and hydraulic regimes. It is shown how the latest microbial tools and techniques can be applied to increase our understanding of DWDS ecology and how water utilities are starting to use this knowledge. This is not because of regulatory requirements, but in recognition that they provide valuable information facilitating proactive management and operation benefits to these critical yet aging systems, protecting water quality and public health in the process.

This article is categorized under:

Engineering Water > Sustainable Engineering of Water

Water and Life > Nature of Freshwater Ecosystems
Traumatic Minor Intracranial Hemorrhage: Management by Non‐neurosurgeon Consultants in a Regional Trauma Center is Safe and Effective
Authors: Khalayleh H. , Lin G. , Kadar Sfarad H. , Mostafa M. , Abu Abed N. , Imam A. , Zbar A. P. , Mavor E.
Published: October 2018

Background

There is debate concerning the need for specialist neurosurgical transfer of patients presenting to Level II trauma centers with a minimal head injury (Glasgow Coma Scale ≥13) and a small non‐progressive intracranial bleeding (ICB).

Methods

A retrospective chart analysis was performed assessing the outcomes of adult patients presenting with a minor traumatic ICB on initial CT scan (minimal subarachnoid hemorrhage; small‐width subdural hematoma without shift; punctate cerebral contusion). Patients with extradural hematomas and those patients on antiplatelet or anticoagulant therapy were excluded from the protocol.

Results

Overall 291 cases were assessed (mean age 69.9 years) with 75% of cases presenting after a fall. There was deterioration of neurological status in 11 patients (3.8%) with 8 hospital transfers and 5 with an abnormal neurological examination (NE). Two patients with an abnormal INR and a worsening head CT were transferred without neurosurgical intervention. Of the 8 transferred cases there were 2 deaths (both >90 years of age with multiple comorbidities) with one craniotomy performed for a subdural hematoma (with full recovery). Three patients meeting transfer criteria were not transferred with one death (patient >90 years of age with severe dementia). The remaining 2 patients were discharged with normal neurological outcomes.

Conclusions

Patients with a minimal traumatic brain injury and a non‐progressive minor ICB may be safely managed in a Level II trauma center by an acute care consultant with neurosurgical consultation but without the need for neurosurgical transfer.

Level of evidence

Retrospective analysis: Level IV.
Honorary Authorships in Surgical Literature
Authors: Luiten J. D. , Verhemel A. , Dahi Y. , Luiten E. J. T. , Gadjradj P. S.
Published: October 2018

Introduction

Honorary authorship (HA) is defined as an enlisted co‐author who did not make sufficient contributions to merit being included as a co‐author according to the ICMJE guidelines on authorship. It is unknown if HA is present in the surgical literature.

Methods

We analysed studies published in 2016 in five journals with the highest impact factor in general surgery. All original articles, reviews and clinical trials with more than one author were included. Corresponding authors of these manuscripts received an online survey by email. The survey consisted of three parts focussing on demographics, knowledge and application of the ICMJE guidelines, and deciding authorship.

Results

In total, 320 of the 1037 surveys were completed (30.9%). Two hundred and seventy‐two (88.6%) of the corresponding authors were aware of the ICMJE authorship guidelines, and 203 (66.3%) were aware of the general issue of honorary authorship. One hundred and thirty‐five (44.0%) responders reported at least one co‐author who only performed tasks which should not merit actual authorship according to the ICMJE guidelines. Furthermore, only 46 (15.0%) of the responders believed that a co‐author listed for their article did not make sufficient contribution to merit being included as co‐author. No significant differences were found between the journals investigated.

Conclusion

Despite ICMJE guidelines to reduce HA, the prevalence may still exist to a higher level than preferable. The authors plead for more transparent authorship systems in which journal editors and senior department members take more responsibility into enforcement of the ICMJE guidelines.
Pharmacology of natural radioprotectors
Authors: Mun Gil-Im , Kim Seoyoung , Choi Eun , Kim Cha Soon , Lee Yun-Sil
Published: October 2018

Radiotherapy is one of the most efficient ways to treat cancer. However, deleterious effects, such as acute and chronic toxicities that reduce the quality of life, may result. Naturally occurring compounds have been shown to be non-toxic over wide dose ranges and are inexpensive and effective. Additionally, pharmacological strategies have been developed that use radioprotectors to inhibit radiation-induced toxicities. Currently available radioprotectors have several limitations, including toxicity. In this review, we present the mechanisms of proven radioprotectors, ranging from free radical scavenging (the best-known mechanism of radioprotection) to molecular-based radioprotection (e.g., upregulating expression of heat shock proteins). Finally, we discuss naturally occurring compounds with radioprotective properties in the context of these mechanisms.