bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthetic Ion Channels and DNA Logic Gates as Components of Molecular Robots
Authors: Kawano Ryuji 
Published: November 2017

AbstractA molecular robot is a next‐generation biochemical machine that imitates the actions of microorganisms. It is made of biomaterials such as DNA, proteins, and lipids. Three prerequisites have been proposed for the construction of such a robot: sensors, intelligence, and actuators. This Minireview focuses on recent research on synthetic ion channels and DNA computing technologies, which are viewed as potential candidate components of molecular robots. Synthetic ion channels, which are embedded in artificial cell membranes (lipid bilayers), sense ambient ions or chemicals and import them. These artificial sensors are useful components for molecular robots with bodies consisting of a lipid bilayer because they enable the interface between the inside and outside of the molecular robot to function as gates. After the signal molecules arrive inside the molecular robot, they can operate DNA logic gates, which perform computations. These functions will be integrated into the intelligence and sensor sections of molecular robots. Soon, these molecular machines will be able to be assembled to operate as a mass microrobot and play an active role in environmental monitoring and in vivo diagnosis or therapy.
Multiple consecutive recapture of rigid nanoparticles using a solid‐state nanopore sensor
Authors: Lee Jung Soo , Peng Bin , Sabuncu Ahmet C. , Nam Seungjin , Ahn ChiWon , Kim Moon J. , Kim MinJun 
Published: November 2017

AbstractSolid‐state nanopore sensors have been used to measure the size of a nanoparticle by applying a resistive pulse sensing technique. Previously, the size distribution of the population pool could be investigated utilizing data from a single translocation, however, the accuracy of the distribution is limited due to the lack of repeated data. In this study, we characterized polystyrene nanobeads utilizing single particle recapture techniques, which provide a better statistical estimate of the size distribution than that of single sampling techniques. The pulses and translocation times of two different sized nanobeads (80 nm and 125 nm in diameter) were acquired repeatedly as nanobeads were recaptured multiple times using an automated system controlled by custom‐built scripts. The drift‐diffusion equation was solved to find good estimates for the configuration parameters of the recapture system. The results of the experiment indicated enhancement of measurement precision and accuracy as nanobeads were recaptured multiple times. Reciprocity of the recapture and capacitive effects in solid state nanopores are discussed. Our findings suggest that solid‐state nanopores and an automated recapture system can also be applied to soft nanoparticles, such as liposomes, exosomes, or viruses, to analyze their mechanical properties in single‐particle resolution.
Schwann cell precursors in health and disease
Authors: Aquino Jorge B. , Sierra Romina 
Published: November 2017

AbstractSchwann cell precursors (SCPs) are frequently regarded as neural crest‐derived cells (NCDCs) found in contact with axons during nerve formation. Nevertheless, cells with SCPs properties can be found up to the adulthood. They are well characterized with regard to both gene expression profile and cellular behavior —for instance, proliferation, migratory capabilities and survival requirements—. They differ in origin regarding their anatomic location: even though most of them are derived from migratory NCCs, there is also contribution of the boundary cap neural crest cells (bNCCs) to the skin and other tissues. Many functions are known for SCPs in normal development, including nerve fasciculation and target innervation, arterial branching patterning and differentiation, and other morphogenetic processes. In addition, SCPs are now known to be a source of many neural (glia, endoneural fibroblasts, melanocytes, visceral neurons, and chromaffin cells) and non‐neural‐like (mesenchymal stromal cells, able e.g., to generate dentine‐producing odontoblasts) cell types. Until now no reports of endoderm‐like derivatives were reported so far. Interestingly, in the Schwann cell lineage only early SCPs are likely able to differentiate into melanocytes and bone marrow mesenchymal stromal cells. We have also herein discussed the literature regarding their role in repair as well as in disease mechanisms, such as in diverse cancers. Moreover, many caveats in our knowledge of SCPs biology are highlighted all through this article. Future research should expand more into the relevance of SCPs in pathologies and in other regenerative mechanisms which might bring new unexpected clinically‐relevant knowledge.
Time to address gender inequalities against female physicians
Authors: Hannawi Suad , Al Salmi Issa 
Published: November 2017

SummaryAlthough the health care system depends heavily on female physicians, it discriminates against women and tends to concentrate female physicians' work in lower status occupations. Gender discrimination has structural, social, and cultural dimensions. Such discrimination is perceived differently by various stakeholders and the public. In addition, there is reluctance to publicly acknowledge gender discrimination, especially in the culturally conservative Middle East region.Gender discrimination leads to underrepresentation of female physicians in leadership roles and certain specialties and hence leads to less attention and understanding of the working conditions of female physicians and their roles in the health care system.The lack of accessible data in the region regarding gender discrimination among physicians leads to stakeholders failing to recognize the existence and magnitude of this type of discrimination. This article takes up the relatively neglected issue of gender discrimination in the health care workforce among the stakeholders of the Ministry of Health and Prevention of the United Arab Emirates.Future research should explore the extent of gender discrimination among physicians and the gender remuneration gap, together with other sorts of discrimination, perception of equal opportunity, and dominant stereotypes of men and women working in health care in relation to job obligation, promotion, retention, remuneration, and education.
Spatial delineation of riparian groundwater within alluvium deposit of mountainous region using Laplace equation
Authors: Ohara Noriaki , Steven Holbrook W. , Yamatani Katsu , Flinchum Brady A. , St. Clair James T. 
Published: November 2017

AbstractThe interaction between surface and groundwater plays a key role in a riparian ecosystem while the size of riparian groundwater has not been typically incorporated into hydrological modelling systems. An extensive geophysical survey composed of 25 individual DC electrical resistivity profiles was conducted at the Blair–Wallis site in Wyoming. The observed resistivity images show a near‐surface aquifer interpreted as the saturated alluvium deposit along the channel, rather than the geological bedrock. Based on the electrical resistivity images, it can be inferred that only the near‐surface portion of the groundwater actively interacts with the stream flow in the mountainous and hilly watershed. This study attempted the spatial extrapolation of the measured riparian aquifer depths by means of fitting functions based on the surface topography. The analysis indicated that the boundary of the riparian aquifer well corresponds to the topographical inflexion point of the hill slope profile. It was also demonstrated that the extent of alluvium deposit, where the area of riparian aquifer is indicated, can be delineated using the slope and curvature maps in the geographic information system. Then, the parabolic and biharmonic functions were tested for the groundwater depth estimation using the developed alluvium deposit map. The proposed methodology was effective if geological diffusion processes by wind and water dominated the topography. The spatial map of the active aquifer will be useful in hydrological drought analysis because it is considered to be a main source of baseflow during dry seasons.
Families of locally separated Hamilton paths
Authors: Körner János , Monti Angelo 
Published: November 2017

AbstractWe improve by an exponential factor the lower bound of Körner and Muzi for the cardinality of the largest family of Hamilton paths in a complete graph of n vertices in which the union of any two paths has maximum degree 4. The improvement is through an explicit construction while the previous bound was obtained by a greedy algorithm. We solve a similar problem for permutations up to an exponential factor.
Spatial and temporal variation of the near‐surface wind environment in the dune fields of northern China
Authors: Cui Xujia , Dong Zhibao , Sun Hu , Li Chao , Xiao Fengjun , Liu Zhengyao , Song Shaopeng , Li Xiaolan , Xiao Nan , Xiao Weiqiang 
Published: November 2017

ABSTRACTResearch on the wind environment provides an important reference for tackling desertification and related environmental issues in desert regions. This article examines spatial and temporal variation of the near‐surface wind environment in the dune fields of northern China, using data from 40 meteorological stations inside and around the dune fields. Wind speed series were first subjected to homogenization, with monthly mean wind speed of the highly correlated neighbour stations as reference series. We found that the homogenized wind speed trends were approximately in accordance with the raw wind speed trends. The wind environment showed spatial and temporal differences, but wind speed has generally decreased both annually and seasonally since 1960, with an average trend of −0.193 m s−1 decade−1. Mean wind speed (1960–2014) and maximum wind speed (1975–2014) decreased significantly, with distinct seasonal differences. The decreasing trend depended strongly on a decreased wind of speeds >5 m s−1 and its frequency. Overall, 48.7–80.8% of the decrease resulted from decreases in the maximum wind speed. Thus, decreases in the maximum wind speed were the dominant change in the study area. We also found that two thirds of the decrease in the drift potential primarily resulted from decreases in three prevailing wind groups (northwest, west, and south winds). This resulted from changes in the East Asian monsoon and westerly circulation. Mean air and ground surface temperatures (1960–2014) increased significantly and were significantly negatively correlated with mean wind speed, whereas sunshine duration (1960–2014) decreased significantly and was significantly positively correlated with mean wind speed. Both correlations reveal that an increasing of atmospheric dust may be responsible for the weakened wind environment. However, China's widespread sand‐control and ecological construction projects have increased ground roughness.
Plant availability of phosphorus from dewatered sewage sludge, untreated incineration ashes, and other products recovered from a wastewater treatment system
Authors: Lemming Camilla , Bruun Sander , Jensen Lars Stoumann , Magid Jakob 
Published: November 2017

AbstractThe objective of the present study was to evaluate the plant phosphorus (P) availability of products derived from new P‐recovery technologies deployed in wastewater treatment systems against sewage sludge and untreated sewage sludge ashes. Eight P sources were evaluated in a six‐week pot experiment with spring barley (Hordeum vulgare L.) and a soil incubation experiment with anaerobically digested and dewatered sewage sludge (Sludge), sewage sludge ash (Ash), thermochemically treated sewage sludge ash (TrAsh), struvite (Struv), concentrate (Conc), and centrifuged concentrate (Prec) from evaporated reject water, with triple super phosphate (TSP), and composted organic household waste (Comp) as references. All sludge‐related materials except struvite came from the same wastewater treatment plant in Denmark. The apparent plant P use efficiency (PUE) of the treatments in the pot experiments was in the following order: Prec (17.0%) > TSP (12.8%) ≥ Conc (12.7%) > Sludge (8.8%) ≥ TrAsh (6.9%) ≥ Struv (6.0%) ≥ Comp (5.8%) > Ash (3.4%). The water‐extractable P (WEP) in the incubation experiment largely supported this order and there was a strong correlation between WEP in the incubation experiment and plant P uptake in the pot experiment. Overall, the results of this study demonstrate that it should not automatically be assumed that products recovered with new treatment technologies for P recovery are more effective P fertilizers than the sewage sludge from which they originate. Furthermore, these results indicate that the measurement of water‐extractable P after soil incubation could be a suitable proxy for plant P availability.
Flow injection gas chromatography with sulfur chemiluminescence detection for the analysis of total sulfur in complex hydrocarbon matrixes
Authors: Hua Yujuan , Hawryluk Myron , Gras Ronda , Shearer Randall , Luong Jim 
Published: November 2017

AbstractA fast and reliable analytical technique for the determination of total sulfur levels in complex hydrocarbon matrices is introduced. The method employed flow injection technique using a gas chromatograph as a sample introduction device and a gas phase dual‐plasma sulfur chemiluminescence detector for sulfur quantification. Using the technique described, total sulfur measurement in challenging hydrocarbon matrices can be achieved in less than 10 s with sample‐to‐sample time <2 min. The high degree of selectivity and sensitivity toward sulfur compounds of the detector offers the ability to measure low sulfur levels with a detection limit in the range of 20 ppb w/w S. The equimolar response characteristic of the detector allows the quantitation of unknown sulfur compounds and simplifies the calibration process. Response is linear over a concentration range of five orders of magnitude, with a high degree of repeatability. The detector's lack of response to hydrocarbons enables direct analysis without the need for time‐consuming sample preparation and chromatographic separation processes. This flow injection‐based sulfur chemiluminescence detection technique is ideal for fast analysis or trace sulfur analysis.
Effects of a Grapevine Shoot Extract Containing Resveratrol and Resveratrol Oligomers on Intestinal Adenoma Development in Mice: In Vitro and In Vivo Studies
Authors: Empl Michael T. , Cai Hong , Wang Shan , Junginger Johannes , Kostka Tina , Hewicker‐Trautwein Marion , Brown Karen , Gescher Andreas J. , Steinberg Pablo 
Published: November 2017

ScopeEvidence suggests that the dietary consumption of plant extracts containing polyphenols might help prevent the onset of cancers of the gastrointestinal tract. In the present study, the chemopreventive and antiproliferative efficacy of a grapevine shoot extract (Vineatrol®30) containing resveratrol and resveratrol oligomers is investigated in vivo and in vitro.Methods and resultsThe in vivo study is performed using ApcMin mice on a high‐fat diet, which represents a model of human adenomatous polyposis, while the potential of the extract as well as some of its isolated constituents to inhibit intestinal adenoma cell proliferation in vitro is investigated using APC10.1 cells derived from an ApcMin mouse. Vineatrol®30 at a low (2.3 mg kg–1 diet) or high dose (476 mg kg–1 diet) reduces the adenoma number in male and adenoma volume in female animals. Furthermore, Vineatrol®30 as well as resveratrol and two resveratrol tetramers compromise the expansion of APC10.1 cells by reducing cell number, inducing cell cycle arrest, cellular senescence, and apoptosis. However, except for the extract, none of the isolated resveratrol oligomers is more efficacious than resveratrol in these cells.ConclusionVineatrol®30 may merit further investigation as a potential dietary gastrointestinal cancer chemopreventive agent in humans.
Vascular input function correction of inflow enhancement for improved pharmacokinetic modeling of liver DCE‐MRI
Authors: Ning Jia , Schubert Tilman , Johnson Kevin M. , Roldán‐Alzate Alejandro , Chen Huijun , Yuan Chun , Reeder Scott B. 
Published: November 2017

PurposeTo propose a simple method to correct vascular input function (VIF) due to inflow effects and to test whether the proposed method can provide more accurate VIFs for improved pharmacokinetic modeling.MethodsA spoiled gradient echo sequence‐based inflow quantification and contrast agent concentration correction method was proposed. Simulations were conducted to illustrate improvement in the accuracy of VIF estimation and pharmacokinetic fitting. Animal studies with dynamic contrast‐enhanced MR scans were conducted before, 1 week after, and 2 weeks after portal vein embolization (PVE) was performed in the left portal circulation of pigs. The proposed method was applied to correct the VIFs for model fitting. Pharmacokinetic parameters fitted using corrected and uncorrected VIFs were compared between different lobes and visits.ResultsSimulation results demonstrated that the proposed method can improve accuracy of VIF estimation and pharmacokinetic fitting. In animal study results, pharmacokinetic fitting using corrected VIFs demonstrated changes in perfusion consistent with changes expected after PVE, whereas the perfusion estimates derived by uncorrected VIFs showed no significant changes.ConclusionThe proposed correction method improves accuracy of VIFs and therefore provides more precise pharmacokinetic fitting. This method may be promising in improving the reliability of perfusion quantification. Magn Reson Med 79:3093–3102, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
On the Traffic Handling Capability of Communication Networks Homogeneously Loaded
Authors: Paz I. 
Published: November 2017

The branch flows in a communication network are normalized against the corresponding branch capacities. The average (µ) of these normalized branch flows is used to represent the traffic load in the network. The sum of all squared differences between the normalized branch flows and µ is defined as the homengeneity (H) of the flow distribution. The capability (P) of a loaded network to handle additional traffic demand increments is then defined as a function of the residual branch capacities, each weighted by a factor representing its topological “importance” in the network.Using the above definitions, several relations are established between H, µ and P. For instance, it is indicated that for a given µ, flow distributions which lead to smaller values of H (better homogeneity) also lead to higher possible values for P (improved network capability).
Bounds on Backtrack Algorithms for Listing Cycles, Paths, and Spanning Trees
Authors: Read R. C. , Tarjan R. E. 
Published: November 2017

ABSTRACTBacktrack algorithms for listing certain kinds of subgraphs of a graph are described and analyzed. Included are algorithms for listing all spanning trees, all cycles, all simple cycles, or all of certain other kinds of paths. The algorithms have 0(V+E) space requirements and 0(V+E+EN) time requirements, if the problem graph has V vertices, E edges, and N subgraphs of the type to be listed.
Lipocalin‐type prostaglandin D synthase‐derived PGD2 attenuates malignant properties of tumor endothelial cells
Authors: Omori Keisuke , Morikawa Teppei , Kunita Akiko , Nakamura Tatsuro , Aritake Kosuke , Urade Yoshihiro , Fukayama Masashi , Murata Takahisa 
Published: November 2017

AbstractEndothelial cells (ECs) are a key component of the tumor microenvironment. They have abnormal characteristics compared to the ECs in normal tissues. Here, we found a marked increase in lipocalin‐type prostaglandin D synthase (L‐PGDS) mRNA (Ptgds) expression in ECs isolated from mouse melanoma. Immunostaining of mouse melanoma revealed expression of L‐PGDS protein in the ECs. In situ hybridization also showed L‐PGDS (PTGDS) mRNA expression in the ECs of human melanoma and oral squamous cell carcinoma. In vitro experiments showed that stimulation with tumor cell‐derived IL‐1 and TNF‐α increased L‐PGDS mRNA expression and its product prostaglandin D2 (PGD2) in human normal ECs. We also investigated the contribution of L‐PGDS–PGD2 to tumor growth and vascularization. Systemic or EC‐specific deficiency of L‐PGDS accelerated the growth of melanoma in mice, whereas treatment with an agonist of the PGD2 receptor, DP1 (BW245C, 0.1 mg/kg, injected intraperitoneally twice daily), attenuated it. Morphological and in vivo studies showed that endothelial L‐PGDS deficiency resulted in functional changes of tumor ECs such as accelerated vascular hyperpermeability, angiogenesis, and endothelial‐to‐mesenchymal transition (EndMT) in tumors, which in turn reduced tumor cell apoptosis. These observations suggest that tumor cell‐derived inflammatory cytokines increase L‐PGDS expression and subsequent PGD2 production in the tumor ECs. This PGD2 acts as a negative regulator of the tumorigenic changes in tumor ECs. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Theoretical evaluation of chemical substitutions along the main chain of poly(3‐hexylthienylene‐vinylene) for solar cell applications
Authors: Roldao Juan Carlos , Oliveira Eliezer Fernando , Sato Fernando , Lavarda Francisco Carlos 
Published: November 2017

AbstractIn order to improve the efficiency of bulk‐heterojunction organic solar cells, one can try to optimize the active layer through the use of new materials that provide improvements in the parameters that influence the final efficiency of a device. The use of chemical substitutions in organic materials already used in these devices seems to be an efficient methodology to obtain new materials with better intrinsic properties. Based on this idea, in this work is investigated theoretically, by methods of electronic structure calculation, a set of 143 poly(3‐hexylthienylene‐vinylene) (P3HTV) derivatives for application in active layers of organic solar cells as electron donor materials; the chemical modifications were performed on the thiophene ring and the vinyl segment of P3HTV. The results show that it is possible to obtain several new derivatives with better optical and electronic properties than those of P3HTV. The derivative substituted with trifluoromethyl on the vinyl segment is one of the most promising for use in active layers, when combined with phenyl‐C61‐butyric‐acid‐methyl‐ester as electron acceptor material. An equation to predict the electronic properties of P3HTV derivatives when using more than one chemical substitution is also proposed, which is corroborated by the theoretical calculations. © 2017 Society of Chemical Industry