bluuebunny/crossref_metadata_2025_split huggingface dataset:
Review of low-cost point-of-use water treatment systems for developing communities
Authors: Pooi Ching Kwek , Ng How Yong 
Published: June 2018

AbstractFor communities in developing countries, the majority of drinking water-related issues are due to pathogens from poor sanitation, resulting in infection and diarrhea. One cause of this is that these communities often do not have access to centralized water treatment facilities. Point-of-use (POU) systems are key solutions for treating water in developing communities; they are typically user-friendly, low cost, low maintenance, and grid-independent. Importantly, they treat and reduce the number of pathogens in water supplies, and many POU systems have been deployed and used by these communities, improving their livelihood. This review focuses on POU systems that cater to households or communities, with the aim to examine and evaluate technologies that have been implemented in POU systems in the past decade.
Transcriptome analysis of microRNA156 overexpression alfalfa roots under drought stress
Authors: Arshad Muhammad , Gruber Margaret Y. , Hannoufa Abdelali 
Published: June 2018

AbstractDrought is one of the major abiotic stresses that negatively impact alfalfa growth and productivity. The role of microRNA156 (miR156) in drought has been demonstrated in plants. To date, there are no published studies investigating the role of miR156 in regulating global gene expression in alfalfa under drought. In our study, alfalfa genotypes overexpressing miR156 (miR156OE) exhibited reduced water loss, and enhanced root growth under drought. Our RNA-seq data showed that in response to drought, a total of 415 genes were upregulated and 169 genes were downregulated specifically in miR156OE genotypes. Genotypic comparison revealed that 285 genes were upregulated and 253 genes were downregulated in miR156OE genotypes relative to corresponding WT under drought. Gene Ontology enrichment analysis revealed that the number of differentially expressed genes belonging to biological process, molecular function and cell component functional groups was decreased in miR156OE genotypes under drought. Furthermore, RNA-Seq data showed downregulation of a gene encoding WD40 repeat in a miR156-specific manner. 5′ RACE experiments verified cleavage of WD40-2 transcript under drought. Moreover, alfalfa plants overexpressing WD40-2 showed drought sensitive, whereas those with silenced WD40-2 exhibited drought tolerant phenotypes. These findings suggest that miR156 improves drought tolerance in alfalfa by targeting WD40-2.
Three-Dimensional Anisotropic Magnetoresistance in the Dirac Node-Line Material ZrSiSe
Authors: Pan Haiyang , Tong Bingbing , Yu Jihai , Wang Jue , Fu Dongzhi , Zhang Shuai , Wu Bin , Wan Xiangang , Zhang Chi , Wang Xuefeng , Song Fengqi 
Published: June 2018

AbstractThe family of materials defined as ZrSiX (X = S, Se, Te) has been established as Dirac node-line semimetals, and subsequent study is urgent to exploit the promising applications of unusual magnetoresistance (MR) properties. Herein, we systematically investigated the anisotropic MR in the newly-discovered Dirac node-line material ZrSiSe. By applying a magnetic field of 3 T by a vector field, three-dimensional (3D) MR shows the strong anisotropy. The MR ratio of maximum and minimum directions reaches 7 at 3 T and keeps increasing at the higher magnetic field. The anisotropic MR forms a butterfly-shaped curve, indicating the quasi-2D electronic structures. This is further confirmed by the angular dependent Shubnikov-de Haas oscillations. The first-principles calculations establish the quasi-2D tubular-shaped Fermi surface near the X point in the Brillouin zone. Our finding sheds light on the 3D mapping of MR and the potential applications in magnetic sensors based on ZrSiSe.
Optical dispersion control in surfactant-free DNA thin films by vitamin B2 doping
Authors: Paulson Bjorn , Shin Inchul , Jeong Hayoung , Kong Byungjoo , Khazaeinezhad Reza , Dugasani Sreekantha Reddy , Jung Woohyun , Joo Boram , Lee Hoi-Youn , Park Sungha , Oh Kyunghwan 
Published: June 2018

AbstractA new route to systematically control the optical dispersion properties of surfactant-free deoxyribonucleic acid (DNA) thin solid films was developed by doping them with vitamin B2, also known as riboflavin. Surfactant-free DNA solid films of high optical quality were successfully deposited on various types of substrates by spin coating of aqueous solutions without additional chemical processes, with thicknesses ranging from 18 to 100 nm. Optical properties of the DNA films were investigated by measuring UV-visible-NIR transmission, and their refractive indices were measured using variable-angle spectroscopic ellipsometry. By doping DNA solid films with riboflavin, the refractive index was consistently increased with an index difference Δn ≥ 0.015 in the spectral range from 500 to 900 nm, which is sufficiently large to make an all-DNA optical waveguide. Detailed correlation between the optical dispersion and riboflavin concentration was experimentally investigated and thermo-optic coefficients of the DNA-riboflavin thin solid films were also experimentally measured in the temperature range from 20 to 85 °C, opening the potential to new bio-thermal sensing applications.
Fundamental ingredients for discontinuous phase transitions in the inertial majority vote model
Authors: Encinas Jesus M. , Harunari Pedro E. , de Oliveira M. M. , Fiore Carlos E. 
Published: June 2018

AbstractDiscontinuous transitions have received considerable interest due to the uncovering that many phenomena such as catastrophic changes, epidemic outbreaks and synchronization present a behavior signed by abrupt (macroscopic) changes (instead of smooth ones) as a tuning parameter is changed. However, in different cases there are still scarce microscopic models reproducing such above trademarks. With these ideas in mind, we investigate the key ingredients underpinning the discontinuous transition in one of the simplest systems with up-down Z2 symmetry recently ascertained in [Phys. Rev. E 95, 042304 (2017)]. Such system, in the presence of an extra ingredient-the inertia- has its continuous transition being switched to a discontinuous one in complex networks. We scrutinize the role of three central ingredients: inertia, system degree, and the lattice topology. Our analysis has been carried out for regular lattices and random regular networks with different node degrees (interacting neighborhood) through mean-field theory (MFT) treatment and numerical simulations. Our findings reveal that not only the inertia but also the connectivity constitute essential elements for shifting the phase transition. Astoundingly, they also manifest in low-dimensional regular topologies, exposing a scaling behavior entirely different than those from the complex networks case. Therefore, our findings put on firmer bases the essential issues for the manifestation of discontinuous transitions in such relevant class of systems with Z2 symmetry.
Understanding tie strength in social networks using a local “bow tie” framework
Authors: Mattie Heather , Engø-Monsen Kenth , Ling Rich , Onnela Jukka-Pekka 
Published: June 2018

AbstractUnderstanding factors associated with tie strength in social networks is essential in a wide variety of settings. With the internet and cellular phones providing additional avenues of communication, measuring and inferring tie strength has become much more complex. We introduce the social bow tie framework, which consists of a focal tie and all actors connected to either or both of the two focal nodes on either side of the focal tie. We also define several intuitive and interpretable metrics that quantify properties of the bow tie which enable us to investigate associations between the strength of the “central” tie and properties of the bow tie. We combine the bow tie framework with machine learning to investigate what aspects of the bow tie are most predictive of tie strength in two very different types of social networks, a collection of medium-sized social networks from 75 rural villages in India and a nationwide call network of European mobile phone users. Our results show that tie strength depends not only on the properties of shared friends, but also on non-shared friends, those observable to only one person in the tie, hence introducing a fundamental asymmetry to social interaction.
Adaptability and reproducibility of a memory disruption rTMS protocol in the PharmaCog IMI European project
Authors: Martin-Trias Pablo , Lanteaume Laura , Solana Elisabeth , Cassé-Perrot Catherine , Fernández-Cabello Sara , Babiloni Claudio , Marzano Nicola , Junqué Carme , Rossini Paolo Maria , Micallef Joëlle , Truillet Romain , Charles Estelle , Jouve Elisabeth , Bordet Régis , Santamaria Joan , Jovicich Jorge , Rossi Simone , Pascual-Leone Alvaro , Blin Olivier , Richardson Jill , Bartrés-Faz David 
Published: June 2018

AbstractTranscranial magnetic stimulation (TMS) can interfere with cognitive processes, such as transiently impairing memory. As part of a multi-center European project, we investigated the adaptability and reproducibility of a previously published TMS memory interfering protocol in two centers using EEG or fMRI scenarios. Participants were invited to attend three experimental sessions on different days, with sham repetitive TMS (rTMS) applied on day 1 and real rTMS on days 2 and 3. Sixty-eight healthy young men were included. On each experimental day, volunteers were instructed to remember visual pictures while receiving neuronavigated rTMS trains (20 Hz, 900 ms) during picture encoding at the left dorsolateral prefrontal cortex (L-DLPFC) and the vertex. Mixed ANOVA model analyses were performed. rTMS to the L-DLPFC significantly disrupted recognition memory on experimental day 2. No differences were found between centers or between fMRI and EEG recordings. Subjects with lower baseline memory performances were more susceptible to TMS disruption. No stability of TMS-induced memory interference could be demonstrated on day 3. Our data suggests that adapted cognitive rTMS protocols can be implemented in multi-center studies incorporating standardized experimental procedures. However, our center and modality effects analyses lacked sufficient statistical power, hence highlighting the need to conduct further studies with larger samples. In addition, inter and intra-subject variability in response to TMS might limit its application in crossover or longitudinal studies.
Directed Self-Assembly of Ge Quantum Dots Using Focused Si2+ Ion Beam Patterning
Authors: Chee See Wee , Kammler Martin , Graham Jeremy , Gignac Lynne , Reuter Mark C. , Hull Robert , Ross Frances M. 
Published: June 2018

AbstractWe show that templating a Si surface with a focused beam of Si2+ or Si+ ions can create suitable nucleation sites for the subsequent growth of self-assembled Ge quantum dots by chemical vapor deposition. To determine the mechanism of patterning we use atomic force microscopy to show that, similar to Ga+ patterning, the formation of a surface pit is required to enable control over Ge quantum dot locations. We find that relatively high implantation doses are required to achieve patterning, and these doses lead to amorphization of the substrate. We assess the degree to which the substrate crystallinity can be recovered by subsequent processing. Using in situ transmission electron microscopy heating experiments we find that recrystallization is possible at the growth temperature of the Ge quantum dots, but defects remain that follow the pattern of the initial implantation. We discuss the formation mechanism of the defects and the benefits of using Si ions for patterning both defects and quantum dots on Si substrates.
Seasonal Response of North Western Pacific Marine Ecosystems to Deposition of Atmospheric Inorganic Nitrogen Compounds from East Asia
Authors: Taketani Fumikazu , Aita Maki N. , Yamaji Kazuyo , Sekiya Takashi , Ikeda Kohei , Sasaoka Kosei , Hashioka Taketo , Honda Makio C. , Matsumoto Kazuhiko , Kanaya Yugo 
Published: June 2018

AbstractThe contribution of the atmospheric deposition of inorganic nitrogen compounds produced in East Asia to the marine ecosystems of the North Western Pacific Ocean (NWPO) was investigated in this study using a 3-D lower trophic-marine ecosystem model (NEMURO) combined with an atmospheric regional chemical transport model (WRF-CMAQ). The monthly mean values for the wet and dry deposition of nitrogen compounds, including gases (HNO3and NH3) and aerosol particles (NO3−and NH4+), were determined using the WRF-CMAQ for the NWPO from 2009–2016. These values were input into the NEMURO as an additional nitrogen source. The NEMURO indicated that the annual average chlorophyll mass concentration at the surface in the subtropical region (20°N–30°N; 125°E–150°E) of the NWPO increased from 0.04 to 0.10 mg/m3. Similarly, the gross primary productivity, integrated over sea depths of 0–200 m, increased from 85 to 147 mg C/m2/day because of this deposition. This study indicates that the supply of atmospheric inorganic nitrogen compounds from East Asia to the NWPO could have a high nutrient impact on the marine ecosystem in the subtropical region.
Influence of growth media components on the antibacterial effect of silver ions on Bacillus subtilis in a liquid growth medium
Authors: De Leersnyder Ilse , De Gelder Leen , Van Driessche Isabel , Vermeir Pieter 
Published: June 2018

AbstractNumerous studies have investigated the antibacterial effect of both silver ions and silver nanomaterials on a large diversity of environmentally and clinically relevant bacteria. However, contradictory results are reported in which inhibition concentrations were varying by a 10-fold. This study investigated whether this variance in results could be attributed to the difference in experimental conditions, especially the microbial growth medium. B. subtilis was exposed to 500 µg L−1 Ag+ in liquid growth media with different concentrations of some commonly used media components: tryptone, yeast extract, Cl−, and S2−. The toxic effect was investigated by means of three complementary analysis techniques: (i) analyzing the growth curves obtained by optical density measurements, (ii) using flow cytometry, and (iii) by transmission electron microscopy. The silver ion toxicity towards B. subtilis decreased as more tryptone, yeast extract, or S2− was present. This study demonstrates that the medium composition, rarely acknowledged as an important experimental factor in bacterial toxicity studies, has a profound impact on the observed silver toxicity towards B. subtilis.
Cell wall associated protein TasA provides an initial binding component to extracellular polysaccharides in dual-species biofilm
Authors: Duanis-Assaf Danielle , Duanis-Assaf Tal , Zeng Guanghong , Meyer Rikke Louise , Reches Meital , Steinberg Doron , Shemesh Moshe 
Published: June 2018

AbstractMany bacteria in biofilm surround themselves by an extracellular matrix composed mainly of extracellular polysaccharide (EP), proteins such as amyloid-like fibers (ALF) and nucleic acids. While the importance of EP in attachment and acceleration of biofilm by a number of different bacterial species is well established, the contribution of ALF to attachment in multispecies biofilm remains unknown. The study presented here aimed to investigate the role of TasA, a precursor for ALF, in cell-cell interactions in dual-species biofilms ofBacillus subtilisandStreptococcus mutans. Expression of majorB.subtilismatrix operons was significantly up-regulated in the presence ofS.mutansduring different stages of biofilm formation, suggesting that the two species interacted and modulated gene expression in each other. Wild-typeB.subtilisexpressing TasA adhered strongly toS.mutansbiofilm, while a TasA-deficient mutant was less adhesive and consequently less abundant in the dual-species biofilm. Dextran, a biofilm polysaccharide, induced aggregation ofB.subtilisand stimulated adhesion toS.mutansbiofilms. This effect was only observed in the wild-type strain, suggesting that interactions between TasA and dextran-associated EP plays an important role in inter-species interactions during initial stages of multispecies biofilm development.
Opto-thermally excited multimode parametric resonance in graphene membranes
Authors: Dolleman Robin J. , Houri Samer , Chandrashekar Abhilash , Alijani Farbod , van der Zant Herre S. J. , Steeneken Peter G. 
Published: June 2018

AbstractIn the field of nanomechanics, parametric excitations are of interest since they can greatly enhance sensing capabilities and eliminate cross-talk. Above a certain threshold of the parametric pump, the mechanical resonator can be brought into parametric resonance. Here we demonstrate parametric resonance of suspended single-layer graphene membranes by an efficient opto-thermal drive that modulates the intrinsic spring constant. With a large amplitude of the optical drive, a record number of 14 mechanical modes can be brought into parametric resonance by modulating a single parameter: the pre-tension. A detailed analysis of the parametric resonance allows us to study nonlinear dynamics and the loss tangent of graphene resonators. It is found that nonlinear damping, of the van der Pol type, is essential to describe the high amplitude parametric resonance response in atomically thin membranes.
Biomimetic post-capillary venule expansions for leukocyte adhesion studies
Authors: Benson Bryan L. , Li Lucy , Myers Jay T. , Dorand R. Dixon , Gurkan Umut A. , Huang Alex Y. , Ransohoff Richard M. 
Published: June 2018

AbstractLeukocyte adhesion and extravasation are maximal near the transition from capillary to post-capillary venule, and are strongly influenced by a confluence of scale-dependent physical effects. Mimicking the scale of physiological vessels usingin vitromicrofluidic systems allows the capture of these effects on leukocyte adhesion assays, but imposes practical limits on reproducibility and reliable quantification. Here we present a microfluidic platform that provides multiple (54–512) technical replicates within a 15-minute sample collection time, coupled with an automated computer vision analysis pipeline that captures leukocyte adhesion probabilities as a function of shear and extensional stresses. We report that in post-capillary channels of physiological scale, efficient leukocyte adhesion requires erythrocytes forcing leukocytes against the wall, a phenomenon that is promoted by the transitional flow in post-capillary venule expansions and dependent on the adhesion molecule ICAM-1.
Inhibition of the substantia nigra pars reticulata produces divergent effects on sensorimotor gating in rats and monkeys
Authors: Aguilar Brittany L. , Forcelli Patrick A. , Malkova Ludise 
Published: June 2018

AbstractThe basal ganglia are an evolutionarily old group of structures, with gross organization conserved across species. Despite this conservation, there is evidence suggesting that anatomical organization of a key output nucleus of the basal ganglia, the substantia nigra pars reticulata (SNpr), diverges across species. Nevertheless, there are relatively few comparative studies examining the impact of manipulations of SNpr across species. Here, we evaluated the role of SNpr in a highly conserved behavior: prepulse inhibition of the acoustic startle response (PPI). We performed parallel experiments in both rats and rhesus macaques using intracranial microinfusions of GABAA agonist muscimol to investigate the role of SNpr in PPI. SNpr inactivation significantly disrupted PPI in rats, congruent with prior studies; however, in macaques, SNpr inactivation resulted in facilitation of PPI. We suggest that this difference in circuit function results from a divergence in anatomical connectivity, underscoring the importance of circuit dissection studies across species.
Imaging in Biologically-Relevant Environments with AFM Using Stiff qPlus Sensors
Authors: Pürckhauer Korbinian , Weymouth Alfred J. , Pfeffer Katharina , Kullmann Lars , Mulvihill Estefania , Krahn Michael P. , Müller Daniel J. , Giessibl Franz J. 
Published: June 2018

AbstractHigh-resolution imaging of soft biological samples with atomic force microscopy (AFM) is challenging because they must be imaged with small forces to prevent deformation. Typically, AFM of those samples is performed with soft silicon cantilevers (k ≈ 0.1–10 N/m) and optical detection in a liquid environment. We set up a new microscope that uses a stiff qPlus sensor (k ≥ 1 kN/m). Several complex biologically-relevant solutions are non-transparent, and even change their optical properties over time, such as the cell culture medium we used. While this would be problematic for AFM setups with optical detection, it is no problem for our qPlus setup which uses electrical detection. The high stiffness of the qPlus sensor allows us to use small amplitudes in frequency-modulation mode and obtain high Q factors even in liquid. The samples are immersed in solution in a liquid cell and long tips are used, with only the tip apex submerged. We discuss the noise terms and compare the minimal detectable signal to that of soft cantilevers. Atomic resolution of muscovite mica was achieved in various liquids: H2O, Tris buffer and a cell culture medium. We show images of lipid membranes in which the individual head groups are resolved.
The Thrombin Receptor Restricts Subventricular Zone Neural Stem Cell Expansion and Differentiation
Authors: Choi Chan-Il , Yoon Hyesook , Drucker Kristen L. , Langley Monica R. , Kleppe Laurel , Scarisbrick Isobel A. 
Published: June 2018

AbstractThrombin is frequently increased in the CNS after injury yet little is known regarding its effects on neural stem cells. Here we show that the subventricular zone (SVZ) of adult mice lacking the high affinity receptor for thrombin, proteinase activated receptor 1 (PAR1), show increased numbers of Sox2+ and Ki-67+ self-renewing neural stem cells (NSCs) and Olig2+ oligodendrocyte progenitors. SVZ NSCs derived from PAR1-knockout mice, or treated with a PAR1 small molecule inhibitor (SCH79797), exhibited enhanced capacity for self-renewal in vitro, including increases in neurosphere formation and BrdU incorporation. PAR1-knockout SVZ monolayer cultures contained more Nestin, NG2+ and Olig2+ cells indicative of enhancements in expansion and differentiation towards the oligodendrocyte lineage. Cultures of NSCs lacking PAR1 also expressed higher levels of myelin basic protein, proteolipid protein and glial fibrillary acidic protein upon differentiation. Complementing these findings, the corpus callosum and anterior commissure of adult PAR1-knockout mice contained greater numbers of Olig2+ progenitors and CC1+ mature oligodendrocytes. Together these findings highlight PAR1 inhibition as a means to expand adult SVZ NSCs and to promote an increased number of mature myelinating oligodendrocytes in vivo that may be of particular benefit in the context of neural injury where PAR1 agonists such as thrombin are deregulated.