bluuebunny/crossref_metadata_2025 huggingface dataset:
Metabolic Engineering Strategies for the Enhanced Microalgal Production of Long‐Chain Polyunsaturated Fatty Acids (LC‐PUFAs)
Authors: Ghiffary Mohammad Rifqi , Kim Hyun Uk , Chang Yong Keun
Published: May 2019

Long‐chain polyunsaturated fatty acids (LC‐PUFAs), largely obtained from fish oil, serve as valuable dietary supplements with many health benefits, especially arachidonic acid, eicosapentaenoic acid, and docosahexaenoic acid. In recent years, interest in the sustainable production of LC‐PUFAs using heterologous production hosts has drastically increased because overfishing and polluted oceans have led to a gradual decline in the supply of LC‐PUFAs from fish oil in the last few decades. Some species of microalgae have been considered to be an ideal producer of LC‐PUFAs as they inherently accumulate large amounts of LC‐PUFAs and utilize CO2 using light energy. Also, a growing number of genetic toolboxes have become available, and the microalgal cultivation process is amenable to a scale‐up. In fact, tremendous progress has been achieved in the development of high‐performance strains of microalgae through metabolic engineering that has led to the efficient production of fatty acids and various derivatives in the last decade. This review discusses metabolic engineering strategies that have contributed to the enhanced production of LC‐PUFAs using microalgae, including optimizing fatty acid biosynthetic pathway and intracellular supply of precursors and cofactors, as well as engineering transcription factors.
Long noncoding RNA RP11‐547D24.1 regulates proliferation and migration in papillary thyroid carcinoma: Identification and validation of a novel long noncoding RNA through integrated analysis of TCGA database
Authors: Guo Kai , Chen Lili , Wang Yunjun , Qian Kai , Zheng Xiaoke , Sun Wenyu , Sun Tuanqi , Wu Yi , Wang Zhuoying
Published: May 2019

Long noncoding RNAs (lncRNAs) are known to be key regulators of numerous biological processes, and substantial evidence supports that abnormal lncRNA expression plays a significant role in tumorigenesis and tumor progression. However, the mechanism by which lncRNAs function in thyroid carcinoma are still unclear. To investigate the role of lncRNAs in the tumorigenesis of papillary thyroid carcinoma (PTC), we analyzed lncRNA data in The Cancer Genome Atlas RNA‐Seq database. A comparison of lncRNAs in cancerous thyroid tissues and normal tissues revealed hundreds of differentially expressed lncRNAs. Of 7589 lncRNAs identified in 561 thyroid cancer cases (503 cancerous tissues and 58 normal tissues), the expression levels of 144 were found to be aberrant (|log2 fold change| >2 and adjusted P < 0.05). The top 10 lncRNAs with the most significant differences were LINC01977, RP11‐363E7.4, RP3‐483K16.4, RP11‐547D24.1, RUNDC3A‐AS1, AC093609.1, CTD‐2008L17.2, HAGLROS, UNC5B‐AS1, and LINC01354. In addition, CTD‐2008L17.2, HAGLROS, AC093609.1, UNC5B‐AS1, and RUNDC3A‐AS1 were shown to play vital roles in determining the histological cancer type. Furthermore, RP11‐547D24.1 and UNC5B‐AS1 could distinguish patients with different stages of PTC. The lncRNA RP11‐547D24.1 was validated by loss‐of‐function assays, revealing that downregulation of this lncRNA regulates thyroid tumor cell proliferation and apoptosis, invasion, and migration. This study demonstrates the potential for using lncRNAs to interpret the pathogenesis and development of PTC.
Inflammatory activation of microglia by Staphylococcus aureus caused phenotypic alterations and affected glioblastoma growth
Authors: Zhang Bo , Zhang Junwen , Fang Sheng , Zhang Mengmeng , Liu Sisi , Tian Yifu , Ma Mengjiao , Liu Fusheng , Jin Guishan
Published: May 2019

As the most common type of tumour in brain, glioma has a high rate of morbidity and mortality and easily penetrates the surrounding normal brain parenchyma. The immunosuppressive microenvironment, which is similar to that in other neoplasms, is believed to participate in the tumorigenesis of glioma. Thus, many experts are seeking to exploit microenvironment as a therapeutic target. In the present study, we focused on microglia polarization to investigate the anti‐glioma response of microglia inflammatory activation by Staphylococcus aureus in vitro and in vivo. First, we found that intratumor injection of S. aureus delayed glioma growth in C57/BL6 mice. Then, we showed that inflammatory microglia activated by S. aureus inhibited glioma cell proliferation, migration, and invasion. This inhibition was likely related to the phenotypic switch observed in microglia. In intracranial tumour models, the microglia activated by S. aureus exerted antitumour efficacy and prolonged animal survival. Taken together, our results suggest that microglia activated by S. aureus have antitumour efficacy, which may be a potential therapeutic agent for glioma.

Significance of the study

In this study, we mainly demonstrated the antitumour efficacy of microglia after activated by S. aureus. Firstly, we found that intratumor injection of S. aureus inhibited the tumour growth in intracranial orthotopic glioma model. In addition, we found that the microglia around the glioma may exert antitumour efficacy, and its phenotype may be altered by stimulation of S. aureus. Our data manifested that S. aureus did not directly suppress cell proliferative, migration, and invasion capacity, but by activating microglia. And in mice GL261 GBMs, injection of microglia after cocultured with S. aureus inhibited tumour growth and prolonged animal survival.
Effect of annealing temperature on morphology and physicochemical properties of cornstarch complexed with oleic acid and molecular dynamics simulation
Authors: Zhang Xing , Wang Yu‐Sheng , Chen Hai‐Hua
Published: May 2019

Background and objectives

Annealing treatment (ANN) as a mild hydrothermal method to improve the complexation between starch and lipids has scarcely been studied. Moreover, the mechanism of starch pretreated by ANN on the complexation between starch and fatty acid still has not been investigated. Therefore, the object of this research was to investigate the effect of ANN pretreatment temperature (50, 55, and 60°C) on the morphology, crystal structure, and thermal properties of CSANN‐OA complex by using confocal laser scanning microscope (CLSM), X‐ray diffraction (XRD), and DSC. The mechanism of the complexation between starch and OA was simulated by the molecular dynamics simulation (MDS) method.

Findings

The results of complex indexes (CI) indicated that CSANN was easier to complex with OA than CSU, and the optimal ANN pretreatment temperature to promote the complexation between CSANN and OA was 50°C. The CLSM displayed that ANN pretreatment at 50°C caused more and stronger fluorescence fragments in CSANN‐OA than that of ANN pretreatment at 55 or 60°C. XRD of both CSU‐OA and CSANN‐OA changed to V‐type crystalline. The relative crystallinity (RC) and gelatinization enthalpy (ΔH) of the complex were decreased with increasing ANN pretreatment temperature, but the gelatinization temperature range (Tc–To) remains unchanged. According to results of MDS, Van der Waals might be dominate driving force between AM and OA.

Conclusions

These results suggest that ANN pretreatment is an effective method to promote the complexation of ANN starch with more polar or nonpolar components.

Significance and novelty

This result can provide available information about the complexation effect and complexation mechanism between starch subjected to ANN pretreatment and fatty acid.
CVX‐based algorithms for constructing various optimal regression designs
Authors: Wong Weng Kee , Zhou Julie
Published: May 2019

CVX‐based numerical algorithms are widely and freely available for solving convex optimization problems but their applications to solve optimal design problems are limited. Using the CVX programs in MATLAB, we demonstrate their utility and flexibility over traditional algorithms in statistics for finding different types of optimal approximate designs under a convex criterion for nonlinear models. They are generally fast and easy to implement for any model and any convex optimality criterion. We derive theoretical properties of the algorithms and use them to generate new A‐, c‐, D‐ and E‐optimal designs for various nonlinear models, including multi‐stage and multi‐objective optimal designs. We report properties of the optimal designs and provide sample CVX program codes for some of our examples that users can amend to find tailored optimal designs for their problems. The Canadian Journal of Statistics 47: 374–391; 2019 © 2019 Statistical Society of Canada
Unusual topographic specializations of retinal ganglion cell density and spatial resolution in a cliff‐dwelling artiodactyl, the Nubian ibex (Capra nubiana)
Authors: Coimbra João Paulo , Alagaili Abdulaziz N. , Bennett Nigel C. , Mohammed Osama B. , Manger Paul R.
Published: May 2019

The Nubian ibex (Capra nubiana) occurs in information‐rich visual habitats including the edges of cliffs and escarpments. In addition to needing enhanced spatial resolution to find food and detect predators, enhanced visual sampling of the lower visual field would be advantageous for the control of locomotion in such precarious terrains. Using retinal wholemounts and stereology, we sought to measure how the ganglion cell density varies across the retina of the Nubian ibex to reveal which portions of its surroundings are sampled with high resolution. We estimated a total of ~1 million ganglion cells in the Nubian ibex retinal ganglion cell layer. Topographic variations of ganglion cell density reveal a temporal area, a horizontal streak, and a dorsotemporal extension, which are topographic retinal features also found in other artiodactyls. In contrast to savannah‐dwelling artiodactyls, the horizontal streak of the Nubian ibex appears loosely organized possibly reflecting a reduced predation risk in mountainous habitats. Estimates of spatial resolving power (~17 cycles/degree) for the temporal area would be reasonable to facilitate foraging in the frontal visual field. Embedded in the dorsotemporal extension, we also found an unusual dorsotemporal area not yet reported in any other mammal. Given its location and spatial resolving power (~6 cycles/degree), this specialization enhances visual sampling toward the lower visual field, which would be advantageous for visually guided locomotion. This study expands our understanding of the retinal organization in artiodactyls and offers insights on the importance of vision for the Nubian ibex ecology.
Self‐compassion, self‐forgiveness, suicidal ideation, and self‐harm: A systematic review
Authors: Cleare Seonaid , Gumley Andrew , O'Connor Rory C.
Published: May 2019

Self‐compassion has been implicated in the aetiology and course of mental health with evidence suggesting an association between greater self‐compassion and lower emotional distress. However, our understanding of the nature and extent of the relationship between self‐compassion and self‐harm (self‐injury regardless of suicidal intent) or suicidal ideation remains unclear. This review, therefore, aimed to critically evaluate the extant literature investigating this relationship. To do so, a systematic search, including terms synonymous with self‐compassion, was conducted on three main psychological and medical databases (Web of Science, PsycINFO, and Medline). Only studies investigating self‐compassion or self‐forgiveness and self‐harm or suicidal ideation were found to be relevant to the review. Eighteen studies were included in the final narrative synthesis. Heterogeneity of studies was high, and the majority of studies were quantitative and cross‐sectional (n = 16) in design. All studies reported significant associations between higher levels of self‐forgiveness or self‐compassion and lower levels of self‐harm or suicidal ideation. Several studies suggested that self‐compassion or self‐forgiveness may weaken the relationship between negative life events and self‐harm. In conclusion, this review highlights the potential importance of self‐compassion in the aetiology of suicidal thoughts and self‐harm. We discuss the clinical and research implications.
Applications of Photoswitches in the Storage of Solar Energy
Authors: Sun Cai‐Li , Wang Chenxu , Boulatov Roman
Published: May 2019

Photoswitches are organic or organometallic chromophores that undergo a reversible chemical transformation upon absorption of light. Among the most commonly studied photoswitches are stilbenes and azobenzenes, capable of efficient interconversion between cis and trans isomers. When one isomer is significantly less thermodynamically stable than the other, photoisomerization of the stable to the metastable isomer converts a fraction of the absorbed photon energy into excess free energy (chemical potential). If the metastable isomer is sufficiently inert at room temperature, its photoconversion provides a means of storing solar energy, which is recovered by triggering heat‐releasing thermal conversion of the metastable to the stable isomer. In other words, such a photoswitch acts as a battery that captures solar energy, stores it as chemical potential and releases it on demand as heat. This process is known as molecular solar thermal energy storage or a molecular solar thermal battery. Unlike the more established conventional solar thermal storage, which uses sunlight to heat, melt or vaporize material, molecular solar thermal energy storage does not require thermal insulation to prevent discharge but relies on the kinetic activation barrier separating the two isomers. Unlike solar‐to‐chemical energy conversion by photosplitting of H2O or photoreduction of CO2, which comprise open‐system cycles, photoswitches are thermodynamically closed storage media. Successful deployment of molecular solar thermal energy storage requires new photoswitches that combine a seemingly contradictory set of molecular parameters: a large difference in the free energies of the two isomers separated by a large kinetic barrier; a high quantum yield of photogeneration of the metastable isomer that itself is either photochemically inactive or transparent to sunlight; highly selective isomerizations that allow many charge/discharge cycles without accumulation of side‐products even at high discharge temperatures. While the optimal photoswitch for molecular solar thermal energy storage remains to be invented, a large body of empirical observations acquired in the past decade provides several potentially valuable starting points for such a search.
Photocatalytic Oxidation of α‐C−H Bonds in Unsaturated Hydrocarbons through a Radical Pathway Induced by a Molecular Cocatalyst
Authors: Zhao Guixia , Hu Bin , Busser G. Wilma , Peng Baoxiang , Muhler Martin
Published: May 2019

To improve the photocatalytic oxidation of α‐C−H bonds in unsaturated hydrocarbons, N‐hydroxyphthalimide (NHPI) was used as a molecular cocatalyst with CdS as the photoabsorber. Compared with previously reported photocatalysts involving solid cocatalysts, metal‐free NHPI offers better sustainability in addition to the significantly enhanced performance as cocatalyst. The photogenerated holes were transferred into the more active phthalimide‐N‐oxyl radical (PINO) by reacting with NHPI. In this way, α‐C−H bond oxidation was significantly improved through the activation by PINO; even for the sluggish toluene oxidation, the apparent quantum efficiency was as high as 36.5 %. The effects of substrates/NHPI concentration ratio, reaction temperature, and time as well as the reaction intermediates were comprehensively studied. It was possible to identify ketones/aldehydes as the primary products, and overoxidation was controlled by adjusting the substrates/NHPI concentration ratio and reaction time. Thus, the radical path induced by the NHPI–PINO redox pair is an efficient alternative to boost the sluggish photocatalytic oxidation of α‐C−H bonds.
Capacitive Sodium‐Ion Storage Based on Double‐Layered Mesoporous Graphene with High Capacity and Charging/Discharging Rate
Authors: Zhu Xiao , Jiang Qinyuan , Wang Tianshuai , Zhang Qianfan , Jia Xilai , Zhang Rufan
Published: May 2019

Sodium‐ion batteries (SIBs) are regarded as an ideal alternative to lithium‐ion batteries, but the larger radius of Na+ compared with Li+ results in lower energy density, shorter cycle life, and sluggish kinetics of SIBs. Therefore, it is of significant importance to explore appropriate Na+ storage materials with high capacity and fast Na+ transport kinetics. Herein, doublelayered mesoporous graphene nanosheets codoped with oxygen and nitrogen (O,N‐MGNSs) were developed as a new cathode material with high Na+ storage capacity and fast ion‐transport kinetics for SIBs. The codoping of MGNSs with oxygen and nitrogen by in situ chemical vapor deposition endowed them with a hierarchical porous network, robust structures, good conductivity, and abundant functional groups. The O,N‐MGNSs could host Na+ in two ways: surface adsorption and surface redox reaction, and this endowed them with high Na+ storage capacity and fast charging/discharging rates in SIBs. Electrochemical results revealed that the O,N‐MGNSs delivered a reversible capacity of 156 mAh g−1 at a current density of 0.5 A g−1 (corresponding to a rate of 3 C) between 1.5 and 4.2 V and exhibited a high cycling stability (95 % capacity retention at 1 A g−1 for more than 1000 cycles).
Can Metallic Sodium Electrodes Affect the Electrochemistry of Sodium‐Ion Batteries? Reactivity Issues and Perspectives
Authors: Pfeifer Kristina , Arnold Stefanie , Becherer Julian , Das Chittaranjan , Maibach Julia , Ehrenberg Helmut , Dsoke Sonia
Published: May 2019

Sodium‐ion batteries (NIBs) are promising energy‐storage devices with advantages such as low cost and highly abundant raw materials. To probe the electrochemical properties of NIBs, sodium metal is most frequently applied as the reference and/or counter electrode in state‐of‐the‐art literature. However, the high reactivity of the sodium metal and its impact on the electrochemical performance is usually neglected. In this study, it is shown that spontaneous reactions of sodium metal with organic electrolytes and the importance of critical interpretation of electrochemical experiments is emphasized. When using sodium‐metal half‐cells, decomposition products contaminate the electrolyte during the electrochemical measurement and can easily lead to wrong conclusions about the stability of the active materials. The cycling stability is highly affected by these electrolyte contaminations, which is proven by comparing sodium‐metal‐free cell with sodium‐metal‐containing cells. Interestingly, a more stable cycling performance of the Li4Ti5O12 half‐cells can be observed when replacing the Na metal counter and reference electrodes with activated carbon electrodes. This difference is attributed to the altered properties of the electrolyte as a result of contamination and to different surface chemistries.
Solar wind driven electrostatic instabilities with generalized (r, q) distribution function
Authors: Nasir Warda , Ehsan Zahida , Qureshi M. N. S. , Shah H. A.
Published: May 2019

Using Boltzmann–Vlasov kinetic model, a currentless ion acoustic instability driven by stream of solar wind plasma is studied in a non‐thermal distributed electrons and ions. The non‐thermal distribution considered here is the generalized distribution which has low energetic flat‐top and velocity power law tail at higher energies. The instability threshold is found to be affected and depends upon the spectral indices r and q. It is found that the growth rate increases with the decrease in the value of r and increase with q. Moreover, such kinetic instability has also been discussed for three species electron–ion–dust plasma using the generalized (r, q) distribution function. Such case is of interest when the solar wind is streaming through the cometary plasma in the presence of interstellar dust and excites electrostatic instabilities. The dispersion properties and growth rates for ion‐acoustic and dust‐acoustic mode are calculated analytically and plotted for different values of the spectral indices r and q.
Effects of non‐extensive electrons on the sheath of dusty plasmas with variable dust charge
Authors: El Ghani O. , Driouch I. , Chatei H.
Published: May 2019

In this study, a detailed investigation of the problem of sheath is presented using the fluid model in a magnetized three‐component dusty plasma system comprising positive ions, dust grains with variable charge and q‐non‐extensive electrons (i.e., the electrons evolve far away from their Maxwellian thermodynamic equilibrium [q = 1]). The effects of q‐non‐extensivity parameter on the plasma sheath parameters are studied numerically. A significant change is observed in the quantities characterizing the sheath with the presence of the super‐extensive electrons (q < 1) and sub‐extensive electrons (q > 1). In addition, based on the orbital motion limited theory, by taking various forces acting on the dust particle into consideration, the dynamics of the dust located within the sheath, that is, the dust grain charging inside the sheath, is examined under different values of q. It is found that the q‐non‐extensivity has affected significantly the dynamics and the charging process of the dust grains in the sheath.
Nelder‐Mead–based power optimization for secrecy enhancement in amplify‐and‐forward cooperative relay networks
Authors: Shemi P.M. , Jibukumar M.G. , Ali M.A.
Published: May 2019

Cooperative communication based on relaying nodes has been considered as a promising technique to increase the physical layer security (PLS) performance in wireless communications. In this paper, an optimal power allocation (OPA) scheme based on Nelder‐Mead (NM) algorithm is proposed for improving the secrecy rate of amplify‐and‐forward (AF) cooperative relay networks employing cooperative jamming (CJ) scheme. The proposed hybrid jamming scheme allows the source and selected relay to transmit the jamming signal along with the information to confound the eavesdropper. The path selection probability of ant colony optimization (ACO) algorithm is used for selecting the relay for transmission. The performance based on secrecy rate is evaluated for “n” trusted relays distributed dispersedly between the source and destination. Gradient‐based optimization and three‐dimensional exhaustive search methods are used as benchmark schemes for comparison of the proposed power optimization algorithm. The secrecy performance is also compared with conventional AF scheme and CJ scheme without power optimization (EPA). The impact of single and multiple relays on secrecy performance is also evaluated. Numerical results reveal that, compared with the gradient method and exhaustive search algorithm, the proposed power allocation strategy achieves optimal performance. Also, the derived OPA results show a significantly higher secrecy rate than the EPA strategy for both CJ and AF schemes.
A simplified deniable authentication scheme in cloud‐based pay‐TV system with privacy protection
Authors: Zhu Hongfeng
Published: May 2019

Cloud computing is a milestones for computing model, which enables on‐demand, flexible, and low‐cost usage of computing resources, especially for cloud storage. Nowadays, the services of cloud‐based pay‐TV systems are emerging endlessly. But these pay‐TV systems' privacy is not given enough attention. The users not only care about their information revealed during transmission processes but are also concerned about whether the video contents that they have seen were recorded by the pay‐TV systems or not. In this work, I propose a novel deniable authentication protocol in a cloud‐based pay‐TV system, named DAP‐TV, aiming to achieve mutual authentication, deniability, and privacy protection in cloud‐based pay‐TV systems. The unique feature of our scheme is deniability which means a pay‐TV system to identify a user is a legal user, but the pay‐TV system cannot prove video contents that the user has seen to any third party over an unsecured network. In additon, our scheme is based on chaotic maps, which is a highly efficient cryptosystem and is firstly used to construct a deniable authentication scheme in pay‐TV systems. Finally, we give the formal security proof and efficiency comparison with recently related works.
Landscape effects on the contemporary genetic structure of Ruffed Grouse (Bonasa umbellus) populations
Authors: Jensen Ashley M. , O'Neil Nicholas P. , Iwaniuk Andrew N. , Burg Theresa M.
Published: May 2019

The amount of dispersal that occurs among populations can be limited by landscape heterogeneity, which is often due to both natural processes and anthropogenic activity leading to habitat loss or fragmentation. Understanding how populations are structured and mapping existing dispersal corridors among populations is imperative to both determining contemporary forces mediating population connectivity, and informing proper management of species with fragmented populations. Furthermore, the contemporary processes mediating gene flow across heterogeneous landscapes on a large scale are understudied, particularly with respect to widespread species. This study focuses on a widespread game bird, the Ruffed Grouse (Bonasa umbellus), for which we analyzed samples from the western extent of the range. Using three types of genetic markers, we uncovered multiple factors acting in concert that are responsible for mediating contemporary population connectivity in this species. Multiple genetically distinct groups were detected; microsatellite markers revealed six groups, and a mitochondrial marker revealed four. Many populations of Ruffed Grouse are genetically isolated, likely by macrogeographic barriers. Furthermore, the addition of landscape genetic methods not only corroborated genetic structure results, but also uncovered compelling evidence that dispersal resistance created by areas of unsuitable habitat is the most important factor mediating population connectivity among the sampled populations. This research has important implications for both our study species and other inhabitants of the early successional forest habitat preferred by Ruffed Grouse. Moreover, it adds to a growing body of evidence that isolation by resistance is more prevalent in shaping population structure of widespread species than previously thought.
Construction of Oxa‐Bridged Tetracyclic Frameworks through a Prins Bicyclic Annulation
Authors: Nair Preethi N. , Swathi Vangala , Nishigandha Ghaytadak , Sridhar Balasubramanian , Reddy Jithender G , Reddy Basi V. Subba
Published: May 2019

A wide array of aldehydes undergo smooth cross‐coupling with 5,6‐bis(2‐hydroxyethyl)‐2‐phenyl‐3a,4,7,7a‐tetrahydro‐1H‐isoindole‐1,3(2H)‐dione in the presence of 1.2 equiv. TMSOTf at –78 °C in dichloromethane to afford the corresponding hexahydro‐8a,4a‐(epoxyethano)pyrano[3,4‐f]isoindole‐1,3(2H,5H)‐dione derivatives in good yields with excellent diastereoselectivity. This is the first report on the stereoselective construction of oxa‐bridged tetracyclic frameworks through a bicyclization strategy.
The Multilevel Regulation of Complex Policy Problems: Uncertainty and the Swine Flu Pandemic
Authors: Versluis Esther , van Asselt Marjolein , Kim Jinhee
Published: May 2019

This article aims at understanding the challenges of tackling complex policy problems in multilevel governance. In order to better grasp the multilevel regulation of complex policy problems, it is needed to understand how uncertainty and scientific expertise are dealt with. We investigate this via the regulation of pandemics by theEUand theWHO, with the H1N1 pandemic of 2009 as critical case. The analysis of the multilevel practice reveals that the attitude toward uncertainty fundamentally differed between the global (WHO) and the European level. At the global level a classic speaking truth to power approach involved the denial of uncertainty, while at theEUlevel the assigned role of providing scientific expertise was interpreted as a necessity to openly communicate about uncertainty. While the global approach was heavily criticized, the uncertainty communication at the European level was much appreciated.
Surface melt‐driven seasonal behaviour (englacial and subglacial) from a soft‐bedded temperate glacier recorded by in situ wireless probes
Authors: Hart Jane K. , Martinez Kirk , Basford Philip J. , Clayton Alexander I. , Bragg Graeme M. , Ward Tyler , Young David S.
Published: May 2019

We investigate the spatial and temporal englacial and subglacial processes associated with a temperate glacier resting on a deformable bed using the unique Glacsweb wireless in situ probes (embedded in the ice and the till) combined with other techniques [including ground penetrating radar (GPR) and borehole analysis]. During the melt season (spring, summer and autumn), high surface melt leads to high water pressures in the englacial and subglacial environment. Winter is characterized by no surface melting on most days (‘base’) apart from a series of positive degree days. Once winter begins, a diurnal water pressure cycle is established in the ice and at the ice/sediment interface, with direct meltwater inputs from the positive degree days and a secondary slower englacial pathway with a five day lag. This direct surface melt also drives water pressure changes in the till. Till deformation occurred throughout the year, with the winter rate approximately 60% that of the melt season. We were able to show the bed comprised patches of till with different strengths, and were able to estimate their size, relative percentage and temporal stability. We show that the melt season is characterized by a high pressure distributed system, and winter by a low pressure channelized system. We contrast this with studies from Greenland (overlying rigid bedrock), where the opposite was found. We argue our results are typical of soft bedded glaciers with low englacial water content, and suggest this type of glacier can rapidly respond to surface‐driven melt. Based on theoretical and field results we suggest that the subglacial hydrology comprises a melt season distributed system dominated by wide anastomosing broad flat channels and thin water sheets, which may become more channelized in winter, and more responsive to changes in meltwater inputs. © 2019 The Authors. Earth Surface Processes and Landforms published by John Wiley & Sons Ltd.
How Important is Bioturbation for Sediment-to-Water Flux of Polycyclic Aromatic Hydrocarbons in the Baltic Sea?
Authors: Mustajärvi Lukas , Nybom Inna , Eriksson-Wiklund Ann-Kristin , Eek Espen , Cornelissen Gerard , Sobek Anna
Published: May 2019

In the present study a recently developed benthic flow-through chamber was used to assess the sediment-to-water flux of polycyclic aromatic hydrocarbons (PAHs) at 4 sites on the Swedish Baltic Sea coast. The flow-through chamber allows for assessment of the potential effect of bioturbation on the sediment-to-water flux of hydrophobic organic contaminants. The sediments at the 4 investigated sites have both varying contamination degree and densities of bioturbating organisms. The flux of individual PAHs measured with the flow-through chamber ranged between 21 and 510, 11 and 370, 3 and 9700, and 62 and 2300 ng m–2 d–1 for the 4 sites. To assess the potential effect of bioturbation on the sediment-to-water flux, 3 flow-through and closed chambers were deployed in parallel at each site. The activity of benthic organisms is attenuated or halted because of depletion of oxygen in closed benthic chambers. Therefore, the discrepancy in flux measured with the 2 different chamber designs was used as an indication of a possible effect of bioturbation. A potential effect of bioturbation on the sediment-to-water flux by a factor of 3 to 55 was observed at sites with a high density of bioturbating organisms (e.g., Marenzelleria spp., Monoporeia affinis, and Macoma balthica of approximately 860–1200 individuals m–2) but not at the site with much lower organism density (<200 individuals m–2). One site had a high organism density and a low potential effect of bioturbation, which we hypothesize to be caused by the dominance of oligochaetes/polychaetes at this site because worms (Marenzelleria spp.) reach deeper into the sediment than native crustaceans and mollusks. Environ Toxicol Chem 2019;38:1803–1810. © 2019 SETAC

Abstract

Sediment-to-water flux of legacy persistent organic pollutants determined by 2 types of benthic chambers: one flow-through chamber allowing for bioturbation, and 1 closed chamber with no bioturbation. The photo to the right shows the chambers before they are placed on the sediment.
A Preliminary Validity Evaluation of a Learning Progression for the Concept of Function
Authors: Graf Edith Aurora , Peters Stephanie , Fife James H. , van Rijn Peter W. , Arieli‐Attali Meirav , Marquez Elizabeth
Published: May 2019

Learning progressions (LPs) describe the development of domain‐specific knowledge, skills, and understanding. Each level of an LP characterizes a phase of student thinking en route to a target performance. The rationale behind LP development is to provide road maps that can be used to guide student thinking from one level to the next. The validity of an LP cannot be taken for granted, however. LPs evolve from a synthesis of multiple research studies, subject‐matter expertise, and standards documents. They are working models of student development that may require revision in light of critique and empirical evidence. The formulation of an LP is an iterative process in which expert feedback is elicited, data are collected, and the LP is revised accordingly. We developed an LP for the concept of function both because the concept of function is challenging to attain and because it is central to the study of algebra and higher mathematics. We report early findings with respect to the validity of the concept of function LP, based on small‐scale cognitive interviews and expert reviews.
Energy‐efficient operation of a network of OpenFlow switches featuring hardware acceleration and frequency scaling
Authors: Ghiasian Ali , Liu Pengcheng , Wang Xiaojun , Collier Martin
Published: May 2019

Recent trends in networking include the move to software‐defined networking, wherein “white‐box” OpenFlow switches unburden control plane functions to a server or the cloud, and network function virtualization (NFV), where network functions traditionally implemented by custom hardware are implemented in generic servers. The use of generic x86 servers reduces costs but limits opportunities to enhance performance and minimise energy consumption. Hardware acceleration techniques used in conjunction with NFV retain the latter's advantages of flexibility and scalability, whilst potentially minimising the energy costs associated with achieving performance targets. In this paper, we utilize field‐programmable gate arrays (FPGAs) for hardware acceleration to perform the switching function of OpenFlow switches. We develop a model of power consumption in a network of FPGA‐based OpenFlow switches. The parameters of the model have been determined empirically using live data from measurements. It has been used in formulating a networkwide optimisation problem wherein frequency scaling is used to minimise power consumption in the network. An online packet routing algorithm is proposed to complete the offline optimisation solution. Our results show that energy efficiency is better achieved when each device operates at an intermediate frequency rather than when the optimisation target is to maximise the number of switches or number of links in sleep state. The improvement is 24% and 40%, respectively. These results suggest a new energy‐efficient flow routing strategy whereby hardware acceleration resources will be utilised to improve energy efficiency.
Curdlan enhances the structure of myosin gel model
Authors: Li Qianru , Wang Peisen , Miao Song , Zhang Longtao , Zheng Baodong
Published: May 2019

The aim of this work was to investigate the gelation mechanism of curdlan on surimi using a myosin gel model. Experimental results showed that with increased levels of curdlan, the water‐holding capacity, gel strength, and storage modulus of a myosin gel first increased and then decreased. The optimum level of curdlan was found to be 1%. Moreover, myosin–curdlan mixed gel showed decreased water liquidity based on the results of low‐field nuclear magnetic resonance. The enhanced physicochemical properties of myosin–curdlan mixed gel were attributed to the strengthened hydrogen bonding and to the uniform and compact network structure shown by Fourier‐transform infrared spectroscopy and scanning electron microscopy. The results of this study suggest that curdlan has the potential to be used in surimi‐based seafood products to enhance the gel structure.
Low‐ and high‐dose aripiprazole augmentation and plasma levels of homovanillic acid in major depressive disorder: A randomized, open‐label study
Authors: Horikoshi Sho , Miura Itaru , Ichinose Mizue , Yamamoto Shinnosuke , Ito Masashi , Watanabe Kenya , Kanno‐Nozaki Keiko , Kaneko Haruka , Yabe Hirooki
Published: May 2019

Objective

This randomized controlled study evaluated the efficacy of low‐dose (LD) and high‐dose (HD) aripiprazole augmentation in major depressive disorder. Additionally, we examined the relationship between clinical response and changes in plasma homovanillic acid (pHVA) levels during aripiprazole augmentation.

Methods

Thirty‐one patients with inadequate response to antidepressants were randomized to receive adjunctive treatment with LD (3 mg/day, n = 17) or HD (up to 12 mg/day, n = 14) aripiprazole for 6 weeks. We evaluated the Montgomery–Åsberg Depression Rating Scale (MADRS) and measured pHVA at baseline, Week 2, and end point.

Results

Both LD and HD aripiprazole significantly decreased MADRS score after 6 weeks, and the response rate was higher in HD aripiprazole group at end point. HD aripiprazole significantly decreased MADRS score at Week 2 compared with LD aripiprazole (p = .015). There was a significant difference in changes in pHVA between responders and nonresponders, showing pHVA decreased significantly in responders at Week 2 (p = .044).

Conclusions

Increasing aripiprazole from the early period appeared useful for immediate response, although caution is needed when increasing the dose >6 mg/day. pHVA may be a possible indicator of the response to aripiprazole augmentation. Caution is needed in interpreting these findings because of the small sample size.
Relationship of circulating tumor cells and Epstein–Barr virus DNA to progression‐free survival and overall survival in metastatic nasopharyngeal carcinoma patients
Authors: You Rui , Liu You‐Ping , Lin Mei , Huang Pei‐Yu , Tang Lin‐Quan , Zhang Yi‐Nuan , Pan Yi , Liu Wan‐Li , Guo Wei‐Bang , Zou Xiong , Zhao Ke‐Ming , Kang Ting , Liu Li‐Zhi , Lin Ai‐Hua , Hong Ming‐Huang , Mai Hai‐Qiang , Zeng Mu‐Sheng , Chen Ming‐Yuan
Published: May 2019

We analyzed the number of circulating tumor cells (CTCs) and Epstein–Barr virus DNA (EBV DNA) for diagnosis, monitoring and prognosis of patients with metastatic nasopharyngeal carcinoma (mNPC). The levels of CTCs and EBV DNA were measured at baseline and after first‐line chemotherapy in 148 mNPC patients prospectively enrolled between December 2014 and August 2016. We also collected 122 non‐mNPC cases within the same time frame for examining CTCs and EBV DNA at baseline. In 270 NPC patients, we observed improved specificity (86.0%vs. 41.0%) and inferior sensitivity (42.3%vs. 81.3%) of CTCs as compared to EBV DNA for diagnosis of distant metastasis. mNPC patients were stratified into unfavorable and favorable prognostic groups, respectively, based on CTC of 12 at baseline and 1 after first‐line chemotherapy and EBV DNA of 10,000 at baseline and 4,000 after first‐line chemotherapy. Conversion of baseline unfavorable CTCs and EBV DNA to favorable after first‐line chemotherapy was associated with significantly longer progression‐free survival (PFS) and overall survival (OS) compared to patients with unfavorable CTCs and EBV DNA at both time points. Among patients with a complete/partial response as per imaging evaluation, favorable CTCs and EBV DNA levels after first‐line chemotherapy were associated with significantly longer PFS and OS. In conclusion, our data demonstrated the number of CTCs and EBV DNA before, after and during first‐line chemotherapy were strong predictive markers for mNPC patients. When utilized in conjunction with imaging studies, CTCs and EBV DNA could provide additional prognostic information.
Advances on three‐dimensional electrodes for micro‐supercapacitors: A mini‐review
Authors: Liu Long , Zhao Huaping , Lei Yong
Published: May 2019

Owing to the high power density, long cycle life and maintain‐free, micro‐supercapacitors (MSCs) stand out as preferred miniaturized energy source for the miscellaneous autonomous electronic components. However, the shortage of energy density is the main stumbling block for their practical applications. To solve this energy issue, constructing a three‐dimensional (3D) electrode within the limited footprint area is proposed as a new solution for improving the energy storage capacity of MSCs. In the last few years, extensive efforts have been devoted to developing 3D electrodes for MSCs, and significant progress and breakthrough have been achieved. While, there is still lack of systematic summary on the 3D electrode design strategies. To this end, it is imperative to outline the basic design conception, summarize the current states, and discuss the future research about 3D electrodes in MSCs based on the latest development.
Assessing preferences of individuals with developmental disabilities using alternative stimulus modalities: A systematic review
Authors: Heinicke Megan R. , Carr James E. , Copsey Catherine J.
Published: May 2019

The purpose of this systematic review was to identify investigations comparing the efficacy of alternative modality (e.g., pictorial, verbal, video) stimulus preference assessments for individuals with developmental disabilities. We identified articles by searching peer‐reviewed journals using the PsycINFO and ERIC databases, conducting table of contents searches of common behavioral outlets, and conducting ancestral searches of recent reviews and practitioner summaries of preference assessment methodology. A total of 32 articles met our inclusion criteria. These studies were then coded across a variety of features to gain a better understanding of the efficacy of alternative format preference assessments for individuals with developmental disabilities. In addition, we reviewed this literature for the use of prerequisite‐skill assessments and contingent‐reinforcer access to further investigate the relation between these variables and the accuracy of pictorial, verbal, and video preference assessments. A variety of methodological concerns are discussed as well as suggestions for future research.
Evaluation of the effects of silver nanoparticles on Danio rerio cornea: Morphological and ultrastructural analysis
Authors: Pecoraro Roberta , Salvaggio Antonio , Scalisi Elena M. , Iaria Carmelo , Lanteri Giovanni , Copat Chiara , Ferrante Margherita , Fragalà Giuseppe , Zimbone Massimo , Impellizzeri Giuliana , Brundo Maria V.
Published: May 2019

Although in recent years there has been intensification in the use of nanoparticles (NPs) for the production of many commercial products, few studies have been carried out to assess the risks associated with its use. Among the most used NPs, silver nanoparticles (AgNPs) have a preponderant position as they have various applications. In this study, 40 adult zebrafish were exposed to increasing concentrations of AgNPs (8, 45, and 70 μg/L) for 30 days to evaluate the effects on eyes after chronic exposure to AgNPs with an average diameter of 50 nm. From the morphological and ultrastructural analysis performed, no alteration or lesions of the corneal epithelium were detected.
Diffusion MR imaging acquisition and analytics for microstructural delineation in pre‐clinical models of TBI
Authors: Harris N. G. , Paydar A. , Smith G. S. , Lepore S.
Published: May 2019

Significant progress has been made toward improving both the acquisition of clinical diffusion‐weighted imaging (DWI) data and its analysis in the uninjured brain, through various techniques including a large number of model‐based solutions that have been proposed to fit for multiple tissue compartments, and multiple fibers per voxel. While some of these techniques have been applied to clinical traumatic brain injury (TBI) research, the majority of these technological enhancements have yet to be fully implemented in the preclinical arena of TBI animal model‐based research. In this review, we describe the requirement for preclinical, MRI‐based efforts to provide systematic confirmation of the applicability of some of these models as indicators of tissue pathology within the injured brain. We review how current DWI techniques are currently being used in animal TBI models, and describe how both acquisition and analytic techniques could be extended to leverage the progress made in clinical work. Finally, we highlight remaining gaps in the preclinical pipeline from data acquisition to final analysis that currently have no real, preclinical‐based correlate.
Effect of the post treatments for biowaste‐based digestates on water solubility of nutrients and iron‐cyanide (Fe‐CN) complex mobility
Authors: Sut‐Lohmann Magdalena , Knoop Christine , Raab Thomas
Published: May 2019

With recent policy developments, an increase in organic waste utilization is expected. However, the use of organic amendments to reduce the mobility of iron‐cyanide (Fe‐CN) complexes and simultaneously promote vegetation growth has not been studied before. Therefore, we evaluated the effect of (a) drying, (b) composting, and (c) pelletizing on the ability of digestates (biowastes from an anaerobic treatment of municipal organic waste) to provide easily available nutrients and stabilize Fe‐CN complexes.

Extraction with deionized water resulted in a considerably higher nutrient and carbon elution from air‐dried and oven‐dried digestates (50% dry matter [DM] of total K, 11% DM Mg, 7% DM Ca, and 6% DM C). Mixer‐pelletized digestates stand out among the composted samples (42% of total K, 3% DM C, 5% DM P, 1.5% DM Mg, and 1% DM Ca). The adsorption experiment showed the highest significant tot. CN conc. reduction using noncomposted, air‐dried (100%), and oven‐dried (82%) digestates. Significant correlations have been found for Mg, Ca, and dissolved organic carbon elution and slightly acidic pH as well as CN adsorption. The Fourier transform infrared analysis revealed Fe‐CN complexation on inorganic (K2Mn[FeII (CN)6] and NH4Fe[FeII (CN)6]) and organic constituents indicating formation of nitriles. Air‐ and oven‐dried digestates showed the most promising results in terms of nutrients' availability and ability to decrease Fe‐CN complex mobility.
Figure of Eight Stereotypies in a Young Girl With a Prenatal Cerebellar Injury
Authors: Dean Shannon L. , Huisman Thierry A.G.M. , Poretti Andrea , Singer Harvey S.
Published: May 2019

View Supplementary Video 1