bluuebunny/crossref_metadata_2025_split huggingface dataset:
Seasonal metabolism and carbon export potential of a key coastal habitat: The perennial canopy‐forming macroalga Fucus vesiculosus
Authors: Attard K. M. , Rodil I. F. , Berg P. , Norkko J. , Norkko A. , Glud R. N. 
Published: October 2018

AbstractThe important role of macroalgal canopies in the oceanic carbon (C) cycle is increasingly being recognized, but direct assessments of community productivity remain scarce. We conducted a seasonal study on a sublittoral Baltic Sea canopy of the brown alga Fucus vesiculosus, a prominent species in temperate and Arctic waters. We investigated community production on hourly, daily, and seasonal timescales. Aquatic eddy covariance (AEC) oxygen flux measurements integrated ~ 40 m2 of the seabed surface area and documented considerable oxygen production by the canopy year‐round. High net oxygen production rates of up to 35 ± 9 mmol m−2 h−1 were measured under peak irradiance of ~ 1200 μmol photosynthetically active radiation (PAR) m−2 s−1 in summer. However, high rates > 15 mmol m−2 h−1 were also measured in late winter (March) under low light intensities < 250 μmol PAR m−2 s−1 and water temperatures of ~ 1°C. In some cases, hourly AEC fluxes documented an apparent release of oxygen by the canopy under dark conditions, which may be due to gas storage dynamics within internal air spaces of F. vesiculosus. Daily net ecosystem metabolism (NEM) was positive (net autotrophic) in all but one of the five measurement campaigns (December). A simple regression model predicted a net autotrophic canopy for two‐thirds of the year, and annual canopy NEM amounted to 25 mol O2 m−2 yr−1, approximately six‐fold higher than net phytoplankton production. Canopy C export was ~ 0.3 kg C m−2 yr−1, comparable to canopy standing biomass in summer. Macroalgal canopies thus represent regions of intensified C assimilation and export in coastal waters.
Environmental controls on pteropod biogeography along the Western Antarctic Peninsula
Authors: Thibodeau P. S. , Steinberg D. K. , Stammerjohn S. E. , Hauri C. 
Published: October 2018

AbstractPteropods are abundant zooplankton in the Western Antarctic Peninsula (WAP) and important grazers of phytoplankton and prey for higher trophic levels. We analyzed long‐term (1993–2017) trends in summer (January–February) abundance of WAP pteropods in relation to environmental controls (sea ice, sea surface temperature, climate indices, phytoplankton biomass and productivity, and carbonate chemistry) and interspecies dynamics using general linear models. There was no overall directional trend in abundance of thecosomes, Limacina helicina antarctica and Clio pyramidata, throughout the entire WAP, although L. antarctica abundance increased in the slope region and C. pyramidata abundance increased in the South. High L. antarctica abundance was strongly tied to a negative Multivariate El Niño Southern Oscillation Index the previous year. C. pyramidata abundance was best explained by early sea ice retreat 1‐yr prior. Abundance of the gymnosome species, Clione antarctica and Spongiobranchaea australis, increased over the time series, particularly in the slope region. Gymnosome abundance was positively influenced by abundance of their prey, L. antarctica, during the same season, and late sea ice advance 2‐yr prior. These trends indicate a shorter ice season promotes longer periods of open water in spring/summer favoring all pteropod species. Weak relationships were found between pteropod abundance and carbonate chemistry, and no long‐term trend in carbonate parameters was detected. These factors indicate ocean acidification is not presently influencing WAP pteropod abundance. Pteropods are responsive to the considerable environmental variability on both temporal and spatial scales—key for predicting future effects of climate change on regional carbon cycling and plankton trophic interactions.
The euphausiid prey field for blue whales around a steep bathymetric feature in the southern California current system
Authors: Nickels Catherine F. , Sala Linsey M. , Ohman Mark D. 
Published: October 2018

AbstractEuphausiids are important prey for many marine organisms and often occur in patchy aggregations. Euphausiid predators, such as blue whales, may become concentrated in the vicinity of these aggregations. We investigated an area called Nine Mile Bank (NMB) near San Diego, California, defined by an area of steep bathymetry, to determine whether the frequent whale sightings in that locality can be explained by the distribution of euphausiids across the bank and by the vertical distribution of euphausiids in the water column. Thysanoessa spinifera, the strongly preferred blue whale prey euphausiid in this area, was consistently more abundant on the bank or inshore of it than offshore. In contrast, Euphausia pacifica, a minor blue whale prey item, was much more abundant and distributed across the study region. Adults of both species were concentrated in a stratum corresponding to the feeding depth of blue whales. Other euphausiids that form a negligible part of the blue whale diet also showed no association with NMB. Both blue whales and their primary prey species Thysanoessa spinifera were more abundant on or inshore of the bank than offshore, suggesting that the bank may serve as an offshore limit of high prey abundance that helps to concentrate blue whales.
Automated plankton image analysis using convolutional neural networks
Authors: Luo Jessica Y. , Irisson Jean‐Olivier , Graham Benjamin , Guigand Cedric , Sarafraz Amin , Mader Christopher , Cowen Robert K. 
Published: October 2018

AbstractThe rise of in situ plankton imaging systems, particularly high‐volume imagers such as the In Situ Ichthyoplankton Imaging System, has increased the need for fast processing and accurate classification tools that can identify a high diversity of organisms and nonliving particles of biological origin. Previous methods for automated classification have yielded moderate results that either can resolve few groups at high accuracy or many groups at relatively low accuracy. However, with the advent of new deep learning tools such as convolutional neural networks (CNNs), the automated identification of plankton images can be vastly improved. Here, we describe an image processing procedure that includes preprocessing, segmentation, classification, and postprocessing for the accurate identification of 108 classes of plankton using spatially sparse CNNs. Following a filtering process to remove images with low classification scores, a fully random evaluation of the classification showed that average precision was 84% and recall was 40% for all groups. Reliably classifying rare biological classes was difficult, so after excluding the 12 rarest taxa, classification accuracy for the remaining biological groups became > 90%. This method provides proof of concept for the effectiveness of an automated classification scheme using deep‐learning methods, which can be applied to a range of plankton or biological imaging systems, with the eventual application in a variety of ecological monitoring and fisheries management contexts.
Exploring Time‐Resolved Multiphysics of Active Plasmonic Systems with Experiment‐Based Gain Models
Authors: Azzam Shaimaa I. , Fang Jieran , Liu Jingjing , Wang Zhuoxian , Arnold Nikita , Klar Thomas A. , Prokopeva Ludmila J. , Meng Xiangeng , Shalaev Vladimir M. , Kildishev Alexander V. 
Published: October 2018

AbstractA systematic approach to investigate lasing and net amplification in plasmonic structures with a finite‐difference time‐domain method coupled to the rate equations of four‐level and six‐level atomic systems is developed. The experiment‐fitted kinetic parameters are fed into the model to study the mechanism of the coupling of metamaterials and metasurfaces with the gain medium. With the help of such an accurate model, net amplification can be distinguished from time‐resolved lasing dynamics for the plasmonic systems coupled with gain.
Direction‐Controlled Bifunctional Metasurface Polarizers
Authors: Chen Yang , Gao Jie , Yang Xiaodong 
Published: October 2018

AbstractMetasurfaces composed of in‐plane subwavelength nanostructures have unprecedented capability in manipulating the amplitude, phase, and polarization states of light. Here, a unique type of direction‐controlled bifunctional metasurface polarizer is proposed and experimentally demonstrated based on plasmonic stepped slit‐groove dimers. In the forward direction, a chiral linear polarizer is enabled which only allows the transmission of a certain incident handedness and converts it into the specified linear polarization. In the backward direction, the metasurface functions as an anisotropic circular polarizer to selectively convert a certain linear polarization component into the desired circularly polarized transmission. The observed direction‐controlled polarization selection and conversion are explained by the spin‐dependent mode coupling process inside the bilayer structure. Anisotropic chiral imaging based on the proposed metasurface polarizer is further demonstrated. The results provide new degrees of freedom to realize future multifunctional photonic integrated devices for structured light conversion, vector beam generation, optical imaging and sensing, and optical communication.
Association of Pretransplant Renal Function With Liver Graft and Patient Survival After Liver Transplantation in Patients With Nonalcoholic Steatohepatitis
Authors: Molnar Miklos Z. , Joglekar Kiran , Jiang Yu , Cholankeril George , Abdul Mubeen Khan Mohammed , Kedia Satish , Gonzalez Humberto C. , Ahmed Aijaz , Singal Ashwani , Bhamidimarri Kalyan Ram , Aithal Guruprasad Padur , Duseja Ajay , Wong Vincent Wai‐Sun , Gulnare Agayeva , Puri Puneet , Nair Satheesh , Eason James D. , Satapathy Sanjaya K. ,   for the Global NAFLD Consortium
Published: October 2018

Nonalcoholic steatohepatitis (NASH) is one of the top 3 indications for liver transplantation (LT) in Western countries. It is unknown whether renal dysfunction at the time of LT has any effect on post‐LT outcomes in recipients with NASH. From the United Network for Organ Sharing–Standard Transplant Analysis and Research data set, we identified 4088 NASH recipients who received deceased donor LT. We divided our recipients a priori into 3 categories: group 1 with estimated glomerular filtration rate (eGFR) <30 mL/minute/1.73 m2 at the time of LT and/or received dialysis within 2 weeks preceding LT (n = 937); group 2 with recipients who had eGFR ≥30 mL/minute/1.73 m2 and who did not receive renal replacement therapy prior to LT (n = 2812); and group 3 with recipients who underwent simultaneous liver‐kidney transplantation (n = 339). We examined the association of pretransplant renal dysfunction with death with a functioning graft, all‐cause mortality, and graft loss using competing risk regression and Cox proportional hazards models. The mean ± standard deviation age of the cohort at baseline was 58 ± 8 years, 55% were male, 80% were Caucasian, and average exception Model for End‐Stage Liver Disease score was 24 ± 9. The median follow‐up period was 5 years (median, 1816 days; interquartile range, 1090‐2723 days). Compared with group 1 recipients, group 2 recipients had 19% reduced trend for risk for death with a functioning graft (subhazard ratio [SHR], 0.81; 95% confidence interval [CI], 0.64‐1.02) and similar risk for graft loss (SHR, 1.25; 95% CI, 0.59‐2.62), whereas group 3 recipients had similar risk for death with a functioning graft (SHR, 1.23; 95% CI, 0.96‐1.57) and graft loss (SHR, 0.18; 95% CI, 0.02‐1.37) using an adjusted competing risk regression model. In conclusion, recipients with preserved renal function before LT showed a trend toward lower risk of death with a functioning graft compared with SLKT recipients and those with pretransplant severe renal dysfunction in patients with NASH.
Impact of Prior Bariatric Surgery on Perioperative Liver Transplant Outcomes
Authors: Idriss Rajab , Hasse Jeanette , Wu Tiffany , Khan Fatima , Saracino Giovanna , McKenna Greg , Testa Giuliano , Trotter James , Klintmalm Goran , Asrani Sumeet K. 
Published: October 2018

Bariatric surgery (BS) is effective in treating morbid obesity, but the impact of prior BS on candidacy for liver transplantation (LT) is unclear. We examined 78 patients with cirrhosis with prior BS compared with a concurrent cohort of 156 patients matched by age, Model for End‐Stage Liver Disease score, and underlying liver disease. We compared rates of transplant denial after evaluation, delisting on the waiting list, and survival after LT. The median time from BS to LT evaluation was 7 years. Roux‐en‐Y gastric bypass was the most common BS procedure performed (63% of cohort). Nonalcoholic fatty liver disease was the leading etiology for liver cirrhosis (47%). Delisting/death on the waiting list was higher among patients with BS (33.3% versus 10.1%; P = 0.002), and the transplantation rate was lower (48.9% versus 65.2%; P = 0.03). Intention‐to‐treat (ITT) survival from listing to 1 year after LT was lower in the BS cohort versus concurrent cohort (1‐year survival, 84% versus 90%; P = 0.05). On adjusted analysis, a history of BS was associated with an increased risk of death on the waiting list (hazard ratio [HR], 5.7; 95% confidence interval [CI], 2.2‐15.1), but this impact was attenuated (HR, 4.9; 95% CI, 1.8‐13.4) by the presence of malnutrition. When limited to matched controls by sex, mortality attributed to BS was no longer significant for females (P = 0.37) but was significant for males (P = 0.046). Sarcopenia, as captured by skeletal muscle index, was calculated in a subset of patients (n = 49). The total skeletal surface area was lower in the BS group (127 [105‐141] cm2 versus 153 [131‐191] cm2; P = 0.005). Rates of sarcopenia were higher among patients delisted after listing (71.4% versus 16.7%; P = 0.04). In conclusion, a history of BS was associated with higher rates of delisting on the waiting list as well as lower survival from the time of listing on ITT analysis. Presence of malnutrition and sarcopenia among patients with BS may contribute to worse outcomes.
Anion‐Mediated Effects on the Size and Mechanical Properties of Enzymatically Crosslinked Suckerin Hydrogels
Authors: Buck Chelsea C. , Dennis Patrick B. , Gupta Maneesh K. , Grant Marcus T. , Crosby Marquise G. , Slocik Joseph M. , Mirau Peter A. , Becknell Kellie A. , Comfort Kristen K. , Naik Rajesh R. 
Published: October 2018

AbstractThe suckerin family of proteins, identified from the squid sucker ring teeth assembly, offers unique mechanical properties and potential advantages over other natural biomaterials. In this study, a small suckerin isoform, suckerin‐12, is used to create enzymatically crosslinked, macro‐scale hydrogels. Upon exposure to specific salt conditions, suckerin‐12 hydrogels contracted into a condensed state where mechanical properties are found to be modulated by the salt anion present. The rate of contraction is found to correlate well with the kosmotropic arm of the Hofmeister anion series. However, the observed changes in hydrogel mechanical properties are better explained by the ability of the salt to neutralize charges in suckerin‐12 by deprotonization or charge screening. Thus, by altering the anions in the condensing salt solution, it is possible to tune the mechanical properties of suckerin‐12 hydrogels. The potential for suckerins to add new properties to materials based on naturally‐derived proteins is highlighted.
Continuous Flow Fabrication of Block Copolymer–Grafted Silica Micro‐Particles in Environmentally Friendly Water/Ethanol Media
Authors: Ye Piaoran , Cao Peng‐Fei , Chen Qiyi , Advincula Rigoberto 
Published: October 2018

AbstractPolymer‐grafted inorganic particles (PGIPs) are attractive building blocks for numerous chemical and material applications. Surface‐initiated controlled radical polymerization (SI‐CRP) is the most feasible method to fabricate PGIPs. However, a conventional in‐batch reaction still suffers from several disadvantages, including time‐consuming purification processes, low grafting efficiency, and possible gelation problems. Herein, a facile method is demonstrated to synthesize block copolymer–grafted inorganic particles, that is, poly(poly(ethylene glycol) methyl ether methacrylate) (PPEGMEMA)‐b‐poly(N‐isopropylacrylamide) (PNIPAM)–grafted silica micro‐particles using continuous flow chemistry in an environmentally friendly aqueous media. Immobilizing the chain transfer agent and subsequent SI‐CRP can be accomplished sequentially in a continuous flow system, avoiding multi‐step purification processes in between. The chain length (MW) of the grafted polymers is tunable by adjusting the flow time or monomer concentration, and the narrower molar mass dispersity (Ð < 1.4) of the grafted polymers reveals the uniform polymer chains on the particles. Moreover, compared with the in‐batch reaction at the same condition, the continuous system also suppresses possible gelation problems.
Carbohydrate‐Based Polymer Brushes Prevent Viral Adsorption on Electrostatically Heterogeneous Interfaces
Authors: Kumar Ramya , Kratzer Domenic , Cheng Kenneth , Prisby Julia , Sugai James , Giannobile William V. , Lahann Joerg 
Published: October 2018

AbstractChemical heterogeneity on biomaterial surfaces can transform its interfacial properties, rendering nanoscale heterogeneity profoundly consequential during bioadhesion. To examine the role played by chemical heterogeneity in the adsorption of viruses on synthetic surfaces, a range of novel coatings is developed wherein a tunable mixture of electrostatic tethers for viral binding, and carbohydrate brushes, bearing pendant α‐mannose, β‐galactose, or β‐glucose groups, is incorporated. The effects of binding site density, brush composition, and brush architecture on viral adsorption, with the goal of formulating design specifications for virus‐resistant coatings are experimentally evaluated. It is concluded that virus‐coating interactions are shaped by the interplay between brush architecture and binding site density, after quantifying the adsorption of adenoviruses, influenza, and fibrinogen on a library of carbohydrate brushes co‐immobilized with different ratios of binding sites. These insights will be of utility in guiding the design of polymer coatings in realistic settings where they will be populated with defects.
On computing highly robust efficient solutions
Authors: Dranichak Garrett M. , Wiecek Margaret M. 
Published: October 2018

AbstractDue to the real‐life issue of decision making in the presence of uncertainty and multiple conflicting objectives, it is of interest to solve optimization problems that incorporate these two aspects. To address this type of problem, we undertake the computation of highly robust efficient solutions to uncertain multiobjective linear programs with objective‐wise uncertainty in the cost matrix coefficients, and we address unbounded feasible regions as well as unbounded uncertainty sets. We provide methods for checking whether or not the highly robust efficient set is empty, computing highly robust efficient points, and determining whether a given solution of interest is highly robust efficient. An application in the area of bank management is included.
Performance analysis of a 3D unidirectional antenna opted for biomedical microwave imaging
Authors: Ullah Md. Amanath , Alam Touhidul , Islam Mohammad Tariqul 
Published: October 2018

AbstractIn this paper, a reflector type unidirectional 3D antenna for biomedical microwave imaging has been presented. A reflector wall perpendicular to the ground plane has been introduced to achieve higher gain and directive radiation pattern. Bending technique is utilized to reduce the overall antenna size and to get resonance at a lower frequency. The proposed antenna obtained measured operating band at 2.37 GHz to 3.70 GHz. The dimension of the 3D radiating structure is 30 × 10 × 17 mm3. The antenna has a peak realized gain of 4.52 dB. Unidirectional radiation pattern and gain within lower microwave frequency, make the proposed antenna a potential candidate to be used in microwave imaging for biomedical diagnosis. The design and simulation process are performed in the CST Microwave Studio software. The antenna is fabricated from 0.2 mm thick copper sheets. PNA Network Analyzer (N5227A) and Satimo Nearfield Measurement system has been used to measure the performance of the fabricated prototype.
Antenna‐based solutions for RF probes in ultra high field magnetic resonance imaging scanners
Authors: Gandji Navid P. , Semouchkin George , Semouchkina Elena 
Published: October 2018

AbstractVarious approaches to designing unconventional antenna‐based RF probes for obtaining homogeneous 600 MHz B1 magnetic field in 14 T MRI scanners are investigated. Proposed solutions include microstrip patch antennas with engineered multidielectric substrates, acting as surface coils, and systems of vis‐à‐vis placed patch antennas to be used as volume coils with essentially increased Q‐factors compared to those of birdcage coils. Various options of controlling magnetic near fields in antenna systems with flat, cylindrical and cosine‐shaped substrates, as well as with tapered patch electrodes, are demonstrated. Problems of fabricating unconventional microstrip patch antennas for MRI applications are also addressed.
Performance enhancement of a microstrip patch antenna using dual‐layer frequency‐selective surface for ISM band applications
Authors: Belen Mehmet A. 
Published: October 2018

AbstractA microstrip patch antenna working at 2.4 GHz at ISM band is presented in this work by employing an altered anchor‐shaped dual‐layer frequency‐selective surface (DLFSS) on a microstrip substrate. Both the traditional method and the proposed one are shown in order to show the advantage of employing this DLFSS structure. In the new technique, simulations and design optimizations of the antennas and FSS structure are undertaken on a low‐cost FR4 substrate with εr = 4.4, h = 1.58 mm and tanδ = 0.0035 in the given 3D CST MSW setting. The traditional FSS technique of the same configuration is also used in the same setting and the outcome of the antenna performance with and without DLFSS is replicated and compared. The results show that the measurements given by the suggested new model are in synchronization with the theoretical results and prove that they have greater gain and beam width at 2.4 GHz bandwidth; they also show improved return loss.
A high‐frequency, low‐coupling 8‐shaped differential inductor with patterned ground shield
Authors: Ichihashi Masahiro , Kanaya Haruichi 
Published: October 2018

AbstractA high‐frequency, low‐coupling 8‐shaped differential inductor with patterned ground shield (PGS) is presented in this paper. The differential structure formed by two single‐inductors in stepping order makes high‐fSR (self‐resonant‐frequency) possible and it also suppresses the far‐field magnetic coupling. A PGS structure not only maximizes the Q‐factor but also improves simulation time and accuracy of EM‐simulation. The test chip is implemented in TSMC 0.18um 1‐poly, 6‐metal CMOS process and the measurement results showed good match with EM‐simulation.