bluuebunny/crossref_metadata_2025 huggingface dataset:
Exploring an AM-Enabled Combination-of-Functions Approach for Modular Product Design
Authors: Chadha Charul , Crowe Kathryn A. , Carmen Christina L. , Patterson Albert E.
Published: October 2018

This work explores an additive-manufacturing-enabled combination-of-function approach for design of modular products. AM technologies allow the design and manufacturing of nearly free-form geometry, which can be used to create more complex, multi-function or multi-feature parts. The approach presented here replaces sub-assemblies within a modular product or system with more complex consolidated parts that are designed and manufactured using AM technologies. This approach can increase the reliability of systems and products by reducing the number of interfaces, as well as allowing the optimization of the more complex parts during the design. The smaller part count and the ability of users to replace or upgrade the system or product parts on-demand should reduce user risk, life-cycle costs, and prevent obsolescence for the user of many systems. This study presents a detailed review on the current state-of-the-art in modular product design in order to demonstrate the place, need and usefulness of this AM-enabled method for systems and products that could benefit from it. A detailed case study is developed and presented to illustrate the concepts.
Hollow Core Optical Fibers for Industrial Ultra Short Pulse Laser Beam Delivery Applications
Authors: Eilzer Sebastian , Wedel Björn
Published: October 2018

Hollow core fibers were introduced many years ago but are now starting to be used regularly in more demanding applications. While first experiments mainly focused on the characterization and analysis of the fibers themselves, they are now implemented as a tool in the laser beam delivery. Owing to their different designs and implementations, different tasks can be achieved, such as flexible beam delivery, wide spectral broadening up to supercontinuum generation or intense gas-laser interaction over long distances. To achieve a constant result in these applications under varying conditions, many parameters of these fibers have to be controlled precisely during fabrication and implementation. A wide variety of hollow core fiber designs have been analyzed and implemented into a high-power industrial beam delivery and their performance has been measured.
Outbreak of Mortality Associated with Acipenser Iridovirus European (AcIV-E) Detection in Siberian Sturgeon (Acipenser baerii) Farmed in Sweden
Authors: Axén Charlotte , Vendramin Niccolò , Toffan Anna
Published: October 2018

Infectious disease is a major challenge in aquaculture and poses a constraint for the development of farming of new species. In 2017, Siberian sturgeon (Acipenser baerii) juveniles were imported from Italy to a Swedish farm. Transport conditions were suboptimal. Thirty percent died during transport and within the first days after arrival. Ten days after arrival, mortalities started to occur again, which prompted initiation of an investigation into the mortalities. Diseased fish were transported live to the National Veterinary Institute (SVA) for necropsy and further analysis. Pathological and histopathological investigation was conducted. Virology was performed on gills and internal organs by cell culture isolation and using specific PCR protocols against nervous necrosis virus (NNV) and Acipenser iridovirus European (AcIV-E). The juveniles displayed neurological signs such as lethargy, inability to maintain an upright position, and erratic swimming. Body condition was below normal, and gills were pale. One fish had petechial hemorrhages on the abdomen and the snout. Two specimens had intestinal hyperemia. Ventricles were air-filled, and swim bladders were deflated. Viral cell cultures gave negative results, but PCR analysis of gills and internal organs detected the presence of AcIV-E. We conclude that AcIV-E was associated with disease and high mortality in the sturgeon juveniles, and stress probably aggravated the course of the infection.
Bioinformatics Analysis and Functional Prediction of Transmembrane Proteins in Entamoeba histolytica
Authors: Anwar Tamanna , Samudrala Gourinath
Published: October 2018

Entamoeba histolytica is an invasive, pathogenic parasite causing amoebiasis. Given that proteins involved in transmembrane (TM) transport are crucial for the adherence, invasion, and nutrition of the parasite, we conducted a genome-wide bioinformatics analysis of encoding proteins to functionally classify and characterize all the TM proteins in E. histolytica. In the present study, 692 TM proteins have been identified, of which 546 are TM transporters. For the first time, we report a set of 141 uncharacterized proteins predicted as TM transporters. The percentage of TM proteins was found to be lower in comparison to the free-living eukaryotes, due to the extracellular nature and functional diversification of the TM proteins. The number of multi-pass proteins is larger than the single-pass proteins; though both have their own significance in parasitism, multi-pass proteins are more extensively required as these are involved in acquiring nutrition and for ion transport, while single-pass proteins are only required at the time of inciting infection. Overall, this intestinal parasite implements multiple mechanisms for establishing infection, obtaining nutrition, and adapting itself to the new host environment. A classification of the repertoire of TM transporters in the present study augments several hints on potential methods of targeting the parasite for therapeutic benefits.
Preventive Dental Care Utilization in Asian Americans in Austin, Texas: Does Neighborhood Matter?
Authors: Yoon Hyunwoo , Jang Yuri , Choi Kwangyul , Kim Hyun
Published: October 2018

Although dental care is an essential component of comprehensive health care, a substantial proportion of the U.S. population lacks access to it. Disparities in dental care are most pronounced in racial/ethnic minority communities. Given the rapid population growth of Asian Americans, as well as the growing attention of neighborhood-level effects on health care use, the present study examines how individual-level variables (i.e., age, gender, marital status, ethnicity, education, place of birth, length of stay in the U.S., dental insurance, and self-rated oral health) and neighborhood-level variables (i.e., poverty level, density of Asian population, dentist availability, and Asian-related resources and services) contribute to predicting the use of preventive dental care in a sample of Asian Americans in Austin, TX. This study adds to the growing literature on the effect of neighborhood-level factors on health care as sources of disparities. Those living in the Census area with higher level of available dentists were more likely to use preventive dental care services. Findings suggest the importance of the location (proximity or accessibility) to dental clinics. In a planning perspective for health care policy, identifying the neighborhood with limited healthcare services could be a priority to diminish the disparity of the access.
Running as a Form of Therapy Socio-Psychological Functions of Mass Running Events for Men and Women
Authors: Malchrowicz-Mośko Ewa , Poczta Joanna
Published: October 2018

The main goal of this study was to recognize the motives of participation in mass running events (Poznan Half Marathon case study). The second aim was to examine the motivations to participate in a half-marathon among two groups of respondents: men and women, and to evaluate the differences between them. The empirical research among runners (n = 560) conducted during the one of the most important running events in Poland recognized the motives for participation in the sports event in accordance with the four basic types of orientation: social orientation, experience orientation, factual orientation, and result orientation (Freyer & Gross, 2002). The significant difference between surveyed men and women appeared in the motives of desire to get away from everyday life and its prevailing fashion, which turned out to be more important for women than for men. The desire to win was not important for the respondents. All respondents reported that what was very important for them was the need to experience strong emotions related to participation, the desire to feel unity and integration with other people, and the desire to test themselves. In general, the results show that people participate in running events not only for physical activity, but also for mental well-being and socio-psychological effects. They experience strong emotions, adrenaline, pleasure, relaxation, and an escape from the duties and hardships of everyday life and have an opportunity to build social relationships thanks to mass sports events organized in urban agglomerations. The article constitutes a conceptualization of the running event in the dimension of social and psychological interactions, which reveal and demonstrate its creative layers and contemporary meaning which has already gone deeply beyond functions of running for health and improving the physical condition.
Comparison of Polar Active Watch and Waist- and Wrist-Worn ActiGraph Accelerometers for Measuring Children’s Physical Activity Levels during Unstructured Afterschool Programs
Authors: Kim Youngdeok , Lochbaum Marc
Published: October 2018

Background: The purpose of this study was to examine the convergent validity of the Polar Active Watch (PAW), a consumer-grade wrist-worn activity monitor, against waist- and wrist-worn research-grade monitors, the ActiGraph GT3X+/GT9X accelerometers, in children. Methods: Fifty-one children (18 boys; mean age = 10.30 ± 0.91 years) wore the three monitors (PAW, GT3X+, and GT9X) during an 80-min afterschool program across five school days. Time spent in sedentary, light-intensity (LPA), and moderate- and vigorous-intensity physical activity (MVPA) were estimated from each monitor. The correlation, mixed model, mean absolute percentage error, equivalence testing, and Bland-Altman analyses were used to examine the comparability of PA estimates of the PAW with GT3X+/GT9X accelerometers. Results: Moderate to strong correlations for sedentary and MVPA minutes, and weak correlation for LPA were observed between the PAW and GT3X+/GT9X accelerometers. Significant mean differences were found, where the PAW tended to overestimate time in sedentary and MVPA and underestimate LPA minutes, compared to the GT3X+/GT9X accelerometers. However, a non-significant mean difference in MVPA minutes was observed when using an adjusted MET threshold (≥4 METs) for the PAW, compared to the GT3X+ accelerometer. Conclusions: The PAW showed moderate convergent validity for sedentary and MVPA minutes against the GT3X+/GT9X accelerometers. However, caution is needed in the direct comparison between the monitors due to relatively large mean differences and within-group variability.
Understanding the Association between Environmental Factors and Longevity in Hechi, China: A Drinking Water and Soil Quality Perspective
Authors: Deng Qucheng , Chen Lijuan , Wei Yongping , Li Yonghua , Han Xuerong , Liang Wei , Zhao Yinjun , Wang Xiaofei , Yin Juan
Published: October 2018

The aging population is a big challenge all over the world. However, there are few studies to date investigating the effects of trace element and mineral levels in drinking water and soil (especially in karst areas) on longevity. This study aims to examine temporal and spatial variations in longevity in Hechi (which is recognized as a longevity city) and to investigate relationships between longevity and trace element and mineral levels in drinking water and soils in this city (the karst landscape). Population data were collected from relevant literature and four national population censuses in 1982, 1990, 2000 and 2010. Drinking water and soil samples from Hechi were collected and analyzed. The results demonstrated an obvious clustered distribution for the longevity population in Hechi that has existed stably for decades. The longevity index tended to be significantly positively correlated with H2SiO3, Ca and Fe in drinking water and significantly negatively correlated with Sr in soil, indicating that drinking water characteristics contributed significantly to the observed regional longevity. The karst landscape is responsible for abundant trace elements in underground rivers in Hechi, which are beneficial to human health when consumed as drinking water. Good quality and slightly alkaline drinking water rich in trace elements such as H2SiO3, Ca, Fe, Na, Mg and low in heavy metals such as Pb and Cd might be an important factor contributing to the longevity phenomenon in Hechi.
Hnf4α Is Involved in LC-PUFA Biosynthesis by Up-Regulating Gene Transcription of Elongase in Marine Teleost Siganus canaliculatus
Authors: Li Yuanyou , Zeng Xiaowei , Dong Yewei , Chen Cuiying , You Cuihong , Tang Guoxia , Chen Junliang , Wang Shuqi
Published: October 2018

The rabbitfish Siganus canaliculatus is the first marine teleost shown to be able to biosynthesize long-chain polyunsaturated fatty acids (LC-PUFA) from C18 PUFA precursors catalyzed by two fatty acyl desaturases (fad) including Δ4 Fad and Δ6/Δ5 Fad as well as two elongases (Elovl4 and Elovl5). Previously, hepatocyte nuclear factor 4α (Hnf4α) was demonstrated to be predominant in the transcriptional regulation of two fads. To clarify the regulatory mechanisms involved in rabbitfish lipogenesis, the present study focused on the regulatory role of Hnf4α to elovl5 expression and LC-PUFA biosynthesis. Bioinformatics analysis predicted two potential Hnf4α elements in elovl5 promoter, one binding site was confirmed to interact with Hnf4α by gel shift assays. Moreover, overexpression of hnf4α caused a remarkable increase both in elovl5 promoter activity and mRNA contents, while knock-down of hnf4α in S. canaliculatus hepatocyte line (SCHL) resulted in a significant decrease of elovl5 gene expression. Meanwhile, hnf4α overexpression enhanced LC-PUFA biosynthesis in SCHL cell, and intraperitoneal injection to rabbitfish juveniles with Hnf4α agonists (Alverine and Benfluorex) increased the expression of hnf4α, elvol5 and Δ4 fad, coupled with an increased proportion of total LC-PUFA in liver. The results demonstrated that Hnf4α is involved in LC-PUFA biosynthesis by up-regulating the transcription of the elovl5 gene in rabbitfish, which is the first report of Hnf4α as a transcription factor of the elovl5 gene in vertebrates.
Group Buying-Based Data Transmission in Flying Ad-Hoc Networks: A Coalition Game Approach
Authors: Ruan Lang , Chen Jin , Guo Qiuju , Zhang Xiaobo , Zhang Yuli , Liu Dianxiong
Published: October 2018

In scenarios such as natural disasters and military strikes, it is common for unmanned aerial vehicles (UAVs) to form groups to execute reconnaissance and surveillance. To ensure the effectiveness of UAV communications, repeated resource acquisition issues and transmission mechanism designs need to be addressed urgently. Since large-scale UAVs will generate high transmission overhead due to the overlapping resource requirements, in this paper, we propose a resource allocation optimization method based on distributed data content in a Flying Ad-hoc network (FANET). The resource allocation problem with the goal of throughput maximization is constructed as a coalition game framework. Firstly, a data transmission mechanism is designed for UAVs to execute information interaction within the coalitions. Secondly, a novel mechanism of coalition selection based on group-buying is investigated for UAV coalitions to acquire data from the central UAV. The data transmission and coalition selection problem are modeled as coalition graph game and coalition formation game, respectively. Through the design of the utility function, we prove that both games have stable solutions. We also prove the convergence of the proposed approach with coalition order and Pareto order. Based on simulation results, coalition order based coalition selection algorithm (CO-CSA) and Pareto order based coalition selection algorithm (PO-CSA) are proposed to explore the stable coalition partition of system model. CO-CSA and PO-CSA can achieve higher data throughput than the contrast onetime coalition selection algorithm (Onetime-CSA) (at least increased by 34.5% and 16.9%, respectively). Besides, although PO-CSA has relatively lower throughput gain, its convergence times is on average 50.9% less than that of CO-CSA, which means that the algorithm choice is scenario-dependent.
Optimization of Parameters on Robotized Gas Metal Arc Welding of LNE 700 High-Strength Steel
Authors: Lermen Richard Thomas , Dal Molin Anderson , Berger Djeison Rangel , Alves Valtair de Jesus , Lisboa Camila Pereira
Published: October 2018

The main aim of this study is to determine the best process parameters for the robotized Gas Metal Arc Welding (GMAW) of LNE 700 advanced high-strength steel. This article evaluates some quality criteria such as the microhardness, the heat-affected zone (HAZ) and the convexity in the welded joints. The assays are performed using an experimental design, based on the Taguchi method. The analysis of the results identified some factors of greatest influence and how best to combine them to determine an optimum condition for welding LNE 700 high strength steel. Moreover, the influence of welding parameters on quality criteria is determined.
Investigations on Material Loads during Grinding by Speckle Photography
Authors: Tausendfreund Andreas , Borchers Florian , Kohls Ewald , Kuschel Sven , Stöbener Dirk , Heinzel Carsten , Fischer Andreas
Published: October 2018

The knowledge of the loads occurring during a manufacturing process (e.g., grinding) and of the modifications remaining in the material is used in the concept of process signatures to optimize the manufacturing process and compare it with others (e.g., laser processing). The prerequisite for creating a process signature is that the loads can be characterized during the running process. Due to the rough process conditions, until now there is no in-process technique to measure the loads in the form of displacements and strains in the machined boundary zone. For this reason, the suitability of speckle photography is demonstrated for in-process measurements of material loads in a grinding process without cooling lubricant and the measurement results are compared with finite element method (FEM) simulations. As working hypothesis for the simulation it is assumed, that dry grinding is a purely thermally driven process. Despite the approximation by a purely thermal model with a constant heat source, the measured displacements differ only by a maximum of approximately 20% from the simulations. In particular, the strain measurements in feed speed direction are in good agreement with the simulation and support the thesis, that the dry grinding conditions used here lead to a primarily thermally affecting process.
An Analysis of Bitcoin’s Price Dynamics
Authors: Kjærland Frode , Khazal Aras , Krogstad Erlend A. , Nordstrøm Frans B. G. , Oust Are
Published: October 2018

This paper aims to enhance the understanding of which factors affect the price development of Bitcoin in order for investors to make sound investment decisions. Previous literature has covered only a small extent of the highly volatile period during the last months of 2017 and the beginning of 2018. To examine the potential price drivers, we use the Autoregressive Distributed Lag and Generalized Autoregressive Conditional Heteroscedasticity approach. Our study identifies the technological factor Hashrate as irrelevant for modeling Bitcoin price dynamics. This irrelevance is due to the underlying code that makes the supply of Bitcoins deterministic, and it stands in contrast to previous literature that has included Hashrate as a crucial independent variable. Moreover, the empirical findings indicate that the price of Bitcoin is affected by returns on the S&P 500 and Google searches, showing consistency with results from previous literature. In contrast to previous literature, we find the CBOE volatility index (VIX), oil, gold, and Bitcoin transaction volume to be insignificant.
Efficient Extraction of a Docosahexaenoic Acid (DHA)-Rich Lipid Fraction from Thraustochytrium sp. Using Ionic Liquids
Authors: Zhang Yujie , Ward Valerie , Dennis Dorothy , Plechkova Natalia V. , Armenta Roberto , Rehmann Lars
Published: October 2018

Polyunsaturated fatty acids (PUFAs) play a significant role in the modulation and prevention of various diseases, and hence are attracting increasing attention from the biotech industry. Thraustochytrids are marine heterokonts that exhibit robust growth rates, high PUFA content, and more specifically, a large percentage of omega-3 fatty acids like docosahexaenoic acid (DHA). Recently, ionic liquids (ILs) have been shown to improve the efficiency of organic solvent extraction of oils from wet oleaginous yeast and microalgae under mild conditions. Two ILs, the imidazolium 1-ethyl-3-methylimidazolium ethylsulfate [C2mim][EtSO4] IL and the phosphonium (tetrabutylphosphonium propanoate [P4444][Prop]) IL were assessed for their ability to facilitate extraction of PUFA-containing lipids from a Thraustochytrium sp. (T18) through efficient cell wall disruption. The oil extracted after IL pretreatment was further characterized with respect to fatty acid methyl ester (FAME) composition, while the effects of process parameters, such as the ratio of ionic liquid to co-solvent, the mass ratio of microalgae to the mixture of ionic liquid, and type of co-solvent were also investigated for both ILs. The results indicate that these ILs can disrupt the cells of Thraustochytrium sp. when mixed with a co-solvent (methanol), and facilitated the recovery of oils over a large degree of dewatered Thraustochytrium biomass (0–77.2 wt% water) in a short period of time (60 min) at ambient temperature, hence demonstrating a water compatible, low-energy, lipid recovery method. The lipid recovery was not affected by repeated usage of recycled ILs (tested up to five times).
Structure and Electrochemical Properties of Mn3O4 Nanocrystal-Coated Porous Carbon Microfiber Derived from Cotton
Authors: Sun Dongya , He Liwen , Lai Yongle , Lian Jiqiong , Sun Jingjing , Xie An , Lin Bizhou
Published: October 2018

Biomorphic Mn3O4 nanocrystal/porous carbon microfiber composites were hydrothermally fabricated and subsequently calcined using cotton as a biotemplate. The as-prepared material exhibited a specific capacitance of 140.8 F·g−1 at 0.25 A·g−1 and an excellent cycle stability with a capacitance retention of 90.34% after 5000 cycles at 1 A·g−1. These characteristics were attributed to the introduction of carbon fiber, the high specific surface area, and the optimized microstructure inherited from the biomaterial.
Amphiphilic Block Copolymer Microspheres Derived from Castor Oil, Poly(ε-carpolactone), and Poly(ethylene glycol): Preparation, Characterization and Application in Naltrexone Drug Delivery
Authors: Nerantzaki Maria , Skoufa Eirini , Adam Kyriakos-Vasileios , Nanaki Stavroula , Avgeropoulos Apostolos , Kostoglou Margaritis , Bikiaris Dimitrios
Published: October 2018

In the present study, the newly synthesized castor oil-derived thioether-containing ω-hydroxyacid (TEHA) block copolymers with polycaprolactone (TEHA-b-PCL), with methoxypoly(ethylene glycol) (mPEG), (TEHA-b-mPEG) and with poly(ethylene glycol) (PEG) (TEHA-b-PEG-b-TEHA), were investigated as polymeric carriers for fabrication of naltrexone (NLX)-loaded microspheres by the single emulsion solvent evaporation technique. These microspheres are appropriate for the long-term treatment of opioid/alcohol dependence. Physical properties of the obtained microspheres were characterized in terms of size, morphology, drug loading capacity, and drug release. A scanning electron microscopy study revealed that the desired NLX-loaded uniform microspheres with a mean particle size of 5–10 µm were obtained in all cases. The maximum percentage encapsulation efficiency was found to be about 25.9% for the microspheres obtained from the TEHA-b-PEG-b-TEHA copolymer. Differential scanning calorimetry and X-ray diffractometry analysis confirmed the drug entrapment within microspheres in the amorphous state. In vitro dissolution studies revealed that all NLX-loaded formulations had a similar drug release profile: An initial burst release after 24 h, followed by a sustained and slower drug release for up to 50 days. The analysis of the release kinetic data, which were fitted into the Korsmeyer–Peppas release model, indicated that diffusion is the main release mechanism of NLX from TEHA-b-PCL and TEHA-b-mPEG microspheres, while microspheres obtained from TEHA-b-PEG-b-TEHA exhibited a drug release closer to an erosion process.
Dual Sensing Performance of 1,2-Squaraine for the Colorimetric Detection of Fe3+ and Hg2+ Ions
Authors: Liu Xiaoqian , Li Na , Xu Min-Min , Jiang Chunhui , Wang Jianhao , Song Guoqiang , Wang Yong
Published: October 2018

A simple 1,2-squaraine based chemosensor material (SQ) has been reported to show dual sensing performance for colorimetric detection of Fe3+ and Hg2+ ions. Compared to common instrumental analysis, this method could provide fast and direct detection though colorimetric changes by the naked eye. The sensor has shown excellent selectivity over the other metal ions by tuning different solvent environments. The detection limit for Fe3+ could reach to 0.538 μM, which was lower than that in the environmental agency guideline (U.S. Environmental Protection Agency, U.S. EPA) in drinking water. And for Hg2+ detection, the limit was calculated as 1.689 μM in our case. A 1:1 binding mode between SQ–Fe3+ and SQ–Hg2+ ion were evidenced by Job’s plot measurement and IR analysis. The proposed different binding mechanisms were also supported by Density Function Theory (DFT) calculation. All these findings provide a unique material and a simple, facile, and low cost colorimetric method for dual metal ions analysis and have shown preliminary analytical applications in industrial water sample analysis.
The Double Roman Domination Numbers of Generalized Petersen Graphs P(n, 2)
Authors: Jiang Huiqin , Wu Pu , Shao Zehui , Rao Yongsheng , Liu Jia-Bao
Published: October 2018

A double Roman dominating function (DRDF) f on a given graph G is a mapping from V ( G ) to { 0 , 1 , 2 , 3 } in such a way that a vertex u for which f ( u ) = 0 has at least a neighbor labeled 3 or two neighbors both labeled 2 and a vertex u for which f ( u ) = 1 has at least a neighbor labeled 2 or 3. The weight of a DRDF f is the value w ( f ) = ∑ u ∈ V ( G ) f ( u ) . The minimum weight of a DRDF on a graph G is called the double Roman domination number γ d R ( G ) of G. In this paper, we determine the exact value of the double Roman domination number of the generalized Petersen graphs P ( n , 2 ) by using a discharging approach.
Some Results on the Deficiencies of Some Differential-Difference Polynomials of Meromorphic Function
Authors: Xu Hong-Yan , Zheng Xiu-Min , Wang Hua
Published: October 2018

For a transcendental meromorphic function f ( z ) , the main aim of this paper is to investigate the properties on the zeros and deficiencies of some differential-difference polynomials. Some results about the deficiencies of some differential-difference polynomials concerning Nevanlinna deficiency and Valiron deficiency are obtained, which are a generalization of and improvement on previous theorems given by Liu, Lan and Zheng, etc.
Experimental Study of the Influence of Ink Properties and Process Parameters on Ejection Volume in Electrohydrodynamic Jet Printing
Authors: Guo Lei , Duan Yongqing , Huang YongAn , Yin Zhouping
Published: October 2018

Electrohydrodynamic jet (e-jet) printing has very promising applications due to its high printing resolution and material compatibility. It is necessary to know how to choose the printing parameters to get the right ejection volume. The previous scaling law of the ejection volume in e-jet printing borrows the scaling law of the ejection volume of an unstable isolated droplet charged to the Rayleigh limit. The influence of viscosity, applied voltage amplitude, and nozzle-to-substrate distance on the ejection volume in e-jet printing was not taken into account in the scaling law. This study investigated the influence of viscosity, conductivity, applied voltage, and nozzle-to-substrate distance on the ejection volume. The ejection volume increases with viscosity and decreases with applied voltage and nozzle-to-substrate distance. The average electric field was kept unchanged while changing the nozzle-to-substrate distance by changing the applied voltage according to the electric field model of a semi-infinite wire perpendicular to an infinite large planar counter electrode. The ejection volume decreases with conductivity as V ~ K − 0.6 , which is different from the previous scaling law, which concludes that V ~ K − 1 . Finally, a model about the relation between the ejection volume and four parameters was established by regression analysis using a third-order polynomial. Two more experiments were done, and the predicted results of the fitted model accorded well with the experiments. The model can be used to choose the ink properties and process parameters to get the right ejection volume.
Automatic Manipulation of Magnetically Actuated Helical Microswimmers in Static Environments
Authors: Liu Jia , Xu Tiantian , Huang Chenyang , Wu Xinyu
Published: October 2018

Electromagnetically actuated microswimmers have been widely used in various biomedical applications due to their minor invasive traits and their easy access to confined environments. In order to guide the microswimmers autonomously towards a target, an obstacle-free path must be computed using path planning algorithms, meanwhile a motion controller must be formulated. However, automatic manipulations of magnetically actuated microswimmers are underdeveloped and still are challenging topics. In this paper, we develop an automatic manipulation system for magnetically actuated helical microswimmers in static environments, which mainly consists of a mapper, a path planner, and a motion controller. First, the mapper processes the captured image by morphological transformations and then labels the free space and the obstacle space. Second, the path planner explores the obstacle-free space to find a feasible path from the start to the goal by a global planning algorithm. Last, the motion controller guides the helical microswimmers along the desired path by a closed-loop algorithm. Experiments are conducted to verify the effectiveness of the proposed automatic manipulation. Furthermore, our proposed approach presents the first step towards applications of microswimmers for targeted medical treatments, such as micromanipulation, targeted therapy, and targeted drug delivery.
Targeting of FGF-Signaling Re-Sensitizes Gastrointestinal Stromal Tumors (GIST) to Imatinib In Vitro and In Vivo
Authors: Boichuk Sergei , Galembikova Aigul , Dunaev Pavel , Micheeva Ekaterina , Valeeva Elena , Novikova Maria , Khromova Natalya , Kopnin Pavel
Published: October 2018

Dysregulation of the fibroblast growth factor (FGF)/fibroblast growth factor receptor (FGFR) signaling pathway is frequently observed in multiple human malignancies, and thus, therapeutic strategies targeting FGFs and FGFRs in human cancer are being extensively explored. We observed the activation of the FGF/FGFR-signaling pathway in imatinib (IM)-resistant gastrointestinal stromal tumor (GIST) cells. Furthermore, we found that the activation of FGFR signaling has a significant impact on IM resistance in GISTs in vitro. Next, we tested the efficacy of BGJ398, a potent and selective FGFR1–3 inhibitor, in xenograft models of GISTs exhibiting secondary IM resistance due to receptor-tyrosine kinase (RTK) switch (loss of c-KIT/gain of FGFR2a). Five to eight-week-old female nu/nu mice were subcutaneously inoculated into the flank areas with GIST T-1R cells. Mice were randomized as control (untreated), IM, BGJ398, or a combination and treated orally for 12 days. IM had a moderate effect on tumor size, thus revealing GIST resistance to IM. Similarly, a minor regression in tumor size was observed in BGJ398-treated mice. Strikingly, a 90% decrease in tumor size was observed in mice treated with a combination of IM and BGJ398. Treatment with BGJ398 and IM also induced major histopathologic changes according to a previously defined histopathologic response score and resulted in massive myxoid degeneration. This was associated with increased intratumoral apoptosis as detected by immunohistochemical staining for cleaved caspase-3 on day 5 of the treatment. Furthermore, treatment with BGJ398 and IM significantly reduced the proliferative activity of tumor cells as measured by positivity for Ki-67 staining. In conclusion, inhibition of FGFR signaling substantially inhibited the growth of IM-resistant GISTs in vitro and showed potent antitumor activity in an IM-resistant GIST model via the inhibition of proliferation, tumor growth, and the induction of apoptosis, thereby suggesting that patients with advanced and metastatic GISTs exhibiting IM resistance might benefit from therapeutic inhibition of FGFR signaling.
Dual QM and MM Approach for Computing Equilibrium Isotope Fractionation Factor of Organic Species in Solution
Authors: Liu Meiyi , Youmans Katelyn N. , Gao Jiali
Published: October 2018

A dual QM and MM approach for computing equilibrium isotope effects has been described. In the first partition, the potential energy surface is represented by a combined quantum mechanical and molecular mechanical (QM/MM) method, in which a solute molecule is treated quantum mechanically, and the remaining solvent molecules are approximated classically by molecular mechanics. In the second QM/MM partition, differential nuclear quantum effects responsible for the isotope effect are determined by a statistical mechanical double-averaging formalism, in which the nuclear centroid distribution is sampled classically by Newtonian molecular dynamics and the quantum mechanical spread of quantized particles about the centroid positions is treated using the path integral (PI) method. These partitions allow the potential energy surface to be properly represented such that the solute part is free of nuclear quantum effects for nuclear quantum mechanical simulations, and the double-averaging approach has the advantage of sampling efficiency for solvent configuration and for path integral convergence. Importantly, computational precision is achieved through free energy perturbation (FEP) theory to alchemically mutate one isotope into another. The PI-FEP approach is applied to model systems for the 18O enrichment found in cellulose of trees to determine the isotope enrichment factor of carbonyl compounds in water. The present method may be useful as a general tool for studying isotope fractionation in biological and geochemical systems.
Synthesis of Binderless ZK-4 Zeolite Microspheres at High Temperature
Authors: Fawaz Elyssa G. , Salam Darine A. , Nouali Habiba , Deroche Irena , Rigolet Severinne , Lebeau Benedicte , Daou T. Jean
Published: October 2018

Binderless zeolite macrostructures in the form of ZK-4 microspheres were prepared using anion-exchange resin beads as shape-directing macrotemplates. The particles were synthesized under hydrothermal conditions at different temperatures and treatment times. The influence of the different synthesis parameters was investigated by X-ray diffraction, scanning electron microscopy, fluorescence X, nitrogen adsorption measurements and 29Si solid-state NMR. Fully crystalline spheres similar in size and shape to the original resin beads were obtained by a hydrothermal treatment at the highest temperatures (150–180 °C) for a short treatment time of 24 h. The synthesized microspheres showed to be promising in the molecular decontamination of volatile organic compounds (VOCs).
Determination of 2′-Fucosyllactose and Lacto-N-neotetraose in Infant Formula
Authors: Austin Sean , Cuany Denis , Michaud Julien , Diehl Bernd , Casado Begoña
Published: October 2018

Human milk oligosaccharides (HMO) are the third most abundant solid component of human milk. It is likely that they are responsible for at least some of the benefits experienced by breast-fed infants. Until recently HMO were absent from infant formula, but 2′-fucosyllactose (2′-FL) and lacto-N-neoteraose (LNnT) have recently become available as ingredients. The development of formula containing these HMO and the quality control of such formula require suitable methods for the accurate determination of the HMO. We developed two different approaches for analysis of 2′-FL and LNnT in formula; high performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD) and hydrophilic interaction liquid chromatography with fluorescence detection (HILIC-FLD). In lab trials using blank formula spiked with the two oligosaccharides, both approaches worked well with recoveries of 94–111% (HPAEC-PAD) and 94–104% (HILIC-FLD) and RSD (iR) of 2.1–7.9% (HPAEC-PAD) and 2.0–7.4% (HILIC-FLD). However, when applied to products produced in a pilot plant, the HPAEC-PAD approach sometimes delivered results below those expected from the addition rate of the ingredients. We hypothesize that the oligosaccharides interact with the formula matrix during the production process and, during sample preparation for HPAEC-PAD those interactions have not been broken. The conditions required for labeling the HMO for detection by the FLD apparently disrupt those interactions, and result in improved recoveries. It is likely that both analytical approaches are appropriate if a suitable extraction process is used to recover the HMO.
Free Radical-Scavenging Capacities, Phenolics and Capsaicinoids in Wild Piquin Chili (Capsicum annuum var. Glabriusculum)
Authors: Moreno-Ramírez Yolanda del Rocio , Martínez-Ávila Guillermo C. G. , González-Hernández Víctor Arturo , Castro-López Cecilia , Torres-Castillo Jorge Ariel
Published: October 2018

The total phenolic compounds content, free radical-scavenging capacity and capsaicinoid content in populations of wild Piquin chili (C. annuum) were studied. Aqueous and hydroalcoholic extracts from nine ecotypes were evaluated. High contents of phenolic compounds and free radical-scavenging capacities were observed for both extracts; however, the values that were found for the hydroalcoholic phase were substantially higher. LC-MS analysis allowed for the detection of 32 compounds, where apigenin-8-C-glucoside followed by vanillic acid 1-O-β-o-glucopyranosylester (Isomer I or II) and 7-ethoxy-4-methylcoumarin were the most widely distributed; they were found in more than 89% of the ecotypes. The diversity of identified phenolic compounds was different among ecotypes, allowing them to be distinguished by chemical diversity, free radical-scavenging capacities and heat Scoville units. The total capsaicinoid content was higher in Population I (23.5 mg/g DW) than in Populations II and III, which had contents of 15.3 and 10.7 mg/g DW, respectively. This variability could lead to phytochemical exploitation and the conservation of the natural populations of wild chili.
Chitosan-Based Nanomaterials for Drug Delivery
Authors: Li Jianghua , Cai Chao , Li Jiarui , Li Jun , Li Jia , Sun Tiantian , Wang Lihao , Wu Haotian , Yu Guangli
Published: October 2018

This review discusses different forms of nanomaterials generated from chitosan and its derivatives for controlled drug delivery. Nanomaterials are drug carriers with multiple features, including target delivery triggered by environmental, pH, thermal responses, enhanced biocompatibility, and the ability to cross the blood-brain barrier. Chitosan (CS), a natural polysaccharide largely obtained from marine crustaceans, is a promising drug delivery vector for therapeutics and diagnostics, owing to its biocompatibility, biodegradability, low toxicity, and structural variability. This review describes various approaches to obtain novel CS derivatives, including their distinct advantages, as well as different forms of nanomaterials recently developed from CS. The advanced applications of CS-based nanomaterials are presented here in terms of their specific functions. Recent studies have proven that nanotechnology combined with CS and its derivatives could potentially circumvent obstacles in the transport of drugs thereby improving the drug efficacy. CS-based nanomaterials have been shown to be highly effective in targeted drug therapy.
Radiation and Energetic Analysis of Nanofluid Based Volumetric Absorbers for Concentrated Solar Power
Authors: Eggers Jan Rudolf , Lange Eckart Matthias , Kabelac Stephan
Published: October 2018

Recently, several publications gave attention to nanofluid based solar absorber systems in which the solar radiation energy is directly absorbed in the volume of the fluid. This idea could provide advantages over conventionally used surface absorbers regarding the optical and thermal efficiency. For the evaluation of this concept, a numerical approach is introduced and validated in this contribution. The results show that the optical efficiency of a volumetric absorber strongly depends on the scattering behavior of the nanofluid and can reach competitive values only if the particle size distribution is narrow and small. If this is achieved, the surface temperature and therefore the heat loss can be lowered significantly. Furthermore, the surface absorber requires very high Reynolds numbers to transfer the absorbed energy into the working fluid and avoid overheating of the absorber tube. This demand of pumping power can be reduced significantly using the concept of volumetric absorption.
Effects of Chemically-Functionalized Single-Walled Carbon Nanotubes on the Morphology and Vitality of D54MG Human Glioblastoma Cells
Authors: Hopkins Seantel , Gottipati Manoj K. , Montana Vedrana , Bekyarova Elena , Haddon Robert C. , Parpura Vladimir
Published: October 2018

The unique properties of single-walled carbon nanotubes (SWCNTs) have made them interesting candidates for applications in biomedicine. There are diverse chemical groups that can be attached to SWCNTs in order for these tiny tubes to gain various functionalities, for example, water solubility. Due to the availability of these “functionalization” approaches, SWCNTs are seen as agents for a potential anti-cancer therapy. In this context, we tested different chemically-functionalized forms of SWCNTs to determine which modifications make them better combatants against glioblastoma (astrocytoma grade IV), the deadliest brain cancer. We investigated the effects that two types of water soluble SWCNTs, functionalized with polyethylene glycol (SWCNT-PEG) or tetrahydrofurfuryl-terminated polyethylene glycol (SWCNT-PEG-THFF), have on the morphology and vitality, that is, cell adhesion, proliferation and death rate, of the D54MG human glioblastoma cells in culture. We found that SWCNT-PEG-THFF solute, when added to culture media, makes D54MG cells less round (measured as a significant decrease, by ~23%, in the form factor). This morphological change was induced by the PEG-THFF functional group, but not the SWCNT backbone itself. We also found that SWCNT-PEG-THFF solute reduces the proliferation rate of D54MG cells while increasing the rate of cell death. The functional groups PEG and PEG-THFF, on the other hand, reduce the cell death rate of D54MG human glioma cells. These data indicate that the process of functionalization of SWCNTs for potential use as glioma therapeutics may affect their biological effects.
Clustering of Excess Body Weight-Related Behaviors in a Sample of Brazilian Adolescents
Authors: De Souza Dantas Mônica , Dos Santos Michel Coutinho , Lopes Luiz Augusto Freire , Guedes Dartagnan Pinto , Guedes Macksuelle Regina Angst , Oesterreich Silvia Aparecida
Published: October 2018

The aim of the study was to identify the existence of clusters in multiple lifestyle behaviors, including consumption of fruits/vegetables, sugary products/soft drinks, physical activity and sedentary behavior. The association between identified clusters and excess body weight in a sample of adolescents from Dourados, Brazil, was examined. This is a cross-sectional school-based study involving 578 participants aged 12–18 of both sexes. Anthropometric measurements were performed and a questionnaire was applied with structured questions to collect data. Excess body weight was identified through body mass index. Cluster analysis was performed to identify sex-specific clusters of multiple lifestyle behaviors. Analysis of covariance and logistic regression were used to analyze associations between clusters and excess body weight. Six clusters were identified in both sexes. Girls and boys in the cluster characterized by greater time spent in sedentary behavior were 53% (OR = 1.53 [1.06–2.26]) and 63% (OR = 1.63 [1.12–2.35]) more likely to present excess body weight compared to their peers in the reference cluster. In the case of adolescents in the cluster characterized by high consumption of sugary products/soft drinks, girls were 47% more likely to be overweight (OR = 1.47 [1.05–2.13]) and boys were 51% more likely (OR = 1.51 [1.05–2.16]). High consumption of fruits/vegetables, low consumption of sugary products/soft drinks and less sedentary behavior was considered the most effective combination for the maintenance of a healthy weight.
Effectiveness of a Program Intervention with Reduced-Iron Multiple Micronutrient Powders on Iron Status, Morbidity and Growth in Young Children in Ethiopia
Authors: Samuel Aregash , Brouwer Inge D. , Feskens Edith J. M. , Adish Abdulaziz , Kebede Amha , De-Regil Luz Maria , Osendarp Saskia J. M.
Published: October 2018

Despite the potential for improving iron status and child growth in low- and middle-income settings, concerns on the safety of high iron dosages of Micronutrient Powders (MNP currently limit their applicability in programs. We examined the effectiveness and risks of an integrated complementary feeding program with low iron dose (6 mg/serving) MNP among 6–23-month-old Ethiopian children using a quasi-experimental study design comparing children from five intervention districts (n = 1172) to those from four matched non-intervention districts (n = 1137). Haemoglobin concentrations increased in intervention and decreased in non-intervention children (group-difference +3.17 g/L), but without improvement in iron stores. Intervention children were 2.31 times more likely to have diarrhoea and 2.08 times more likely to have common cold and flu, but these differences decreased towards the end of the intervention. At end line, intervention children had higher mean Height-for-Age Zscore (HAZ) and a 51% reduced odds of being stunted compared to non-intervention children. MNP with low iron dose, when provided combined with other Infant and Young Child Feeding (IYCF) interventions, marginally improved haemoglobin status and resulted in a remarkable improvement in linear growth in 6–23-month-old children. These benefits likely outweigh the relatively small increase in the risk of diarrhoea.