bluuebunny/crossref_metadata_2025 huggingface dataset:
Skolans laborationer och traditionens makt
Authors: Lunde Torodd
Published: February 2019

Traditioner har makt över hur vi tänker. När vi nu enligt nya läroplanen Lgr11 ska börja genomföra laborationer i syftet att ge eleverna kunskaper om den naturvetenskapliga forskningsprocessen, finns stor sannolikhet att uppdraget påverkas av den laborationstradition som redan finns. Det visar en fallstudie där samtliga högstadielärare i NO-ämnen inom en kommun deltog. Därför behövs nya laborationer som gynnar det kritiska tänkandet.
Kontextens roll i ett TPRS-klassrum
Authors: Dokalik-Jonak Elisabeth , Kemsies Ronald
Published: February 2019

I denna artikel presenteras tre utvalda dimensioner som vi sammanfattar i termen ”kontextkänslighet”. Vi försöker i artikeln visa hur auditiva, visuella och lingvistiska komponenter understödjer en TPRS 1 -lektion i främmande språk. En undervisnings­sekvens presenteras där våra idéer och förslag kommer till uttryck.
Learning study i dans
Authors: Ahlstrand Pernilla
Published: February 2019

Det som tidigare har tagit en termin att lära eleverna lär de sig nu på ett par veckor. Så effektivt kan det vara att arbeta med modellen learning study i undervisningen.

Medförfattare och faktagranskare: Lina Andersson, Susanne Skårstedt, Annica Lindholm Tejfors och Helena Uhr .
Utomhusdidaktik i högstadiet – fungerar det?
Authors: Fägerstam Emilia
Published: February 2019

”Det kommer aldrig att fungera, det är ju tonåringar det handlar om, tänk om det regnar. De vill inte gå ut”. Det är en vanlig farhåga inför att undervisa utanför klassrummet och yttrades av en lärare inför vårt forskningsprojekt i utomhusdidaktik för högstadieelever. Fick läraren rätt? Vad tycker lärare i år 7–9 om utomhusdidaktik efter ett år av regelbunden utomhusundervisning?
Estimating Body Condition Score in Dairy Cows From Depth Images Using Convolutional Neural Networks, Transfer Learning and Model Ensembling Techniques
Authors: Rodríguez Alvarez Juan , Arroqui Mauricio , Mangudo Pablo , Toloza Juan , Jatip Daniel , Rodriguez Juan M. , Teyseyre Alfredo , Sanz Carlos , Zunino Alejandro , Machado Claudio , Mateos Cristian
Published: February 2019

BCS (Body Condition Score) is a method to estimate body fat reserves and accumulated energy balance of cows, placing estimations (or BCS values) in a scale of 1 to 5. Periodically rating BCS of dairy cows is very important since BCS values are associated with milk production, reproduction, and health of cows. However, in practice, obtaining BCS values is a time-consuming and subjective task performed visually by expert scorers. There have been several efforts to automate BCS of dairy cows by using image analysis and machine learning techniques. In a previous work, an automatic system to estimate BCS values was proposed, which is based on Convolutional Neural Networks (CNNs). In this paper we significantly extend the techniques exploited by that system via using transfer learning and ensemble modeling techniques to further improve BCS estimation accuracy. The improved system has achieved good estimations results in comparison with the base system. Overall accuracy of BCS estimations within 0.25 units of difference from true values has increased 4% (up to 82%), while overall accuracy within 0.50 units has increased 3% (up to 97%).
Feeding Conjugated Linoleic Acid without a Combination of Medium-Chain Fatty Acids during Late Gestation and Lactation Improves Pre-Weaning Survival Rates of Gilt and Sow Progeny
Authors: Craig Jessica R. , Dunshea Frank R. , Cottrell Jeremy J. , Ford Erin M. , Wijesiriwardana Udani A. , Pluske John R.
Published: February 2019

Feeding conjugated linoleic acid (CLA) or medium-chain fatty acids (MCFA) to dams has been shown to improve progeny growth and survival, and hence may be particularly advantageous to gilt progeny. Primiparous (n = 129) and multiparous sows (n = 123; parities 3 and 4) were fed one of four diets from day 107 of gestation (107.3 ± 0.1 days) until weaning (day 27.2 ± 0.1 of lactation): (i) control diet; (ii) 0.5% CLA diet; (iii) 0.1% MCFA diet; and (iv) equal parts of (ii) and (iii). Progeny performance data were collected and, from a subset of sows (n = 78) and their piglets (n = 144), a colostrum (day 0), milk (day 21), and piglet serum sample (day 3) were analyzed for immunoglobulin G and several selected metabolites. Liveborn pre-weaning mortality tended to be lowest (p = 0.051) in piglets from sows fed 0.5% CLA. However, sows fed the CLA diet had more (p = 0.005) stillbirths than those on the other diets. There were few effects of diet or the dam parity x diet interaction (p ≥ 0.05) on other parameters. Overall, feeding CLA or MCFA did not improve the performance of primiparous sows, multiparous sows, or their progeny.
Effect of Breed on Transcriptional and Protein Expression of Lipogenic Enzymes in Tail and Subcutaneous Adipose Tissue from Two Grazing Breeds of Lambs
Authors: Gallardo María , Arias-Darraz Luis , Cárcamo Juan
Published: February 2019

This experiment was carried out to determine the effect of breed on mRNA and protein expression levels of lipogenic enzymes acetyl-CoA carboxylase α (ACC), fatty acid synthase (FAS), stearoyl-CoA desaturase 1 (SCD1) plus sterol regulatory element binding transcription factor 1c (SREBP1c) in the subcutaneous fat (SCF) from the back of the animal, and tail fat (TF) of both Chilota and Suffolk Down lambs grazing Calafatal. Eight Chilota and six Suffolk Down 2-month-old male lambs were allocated to graze a “Calafatal”, a typical secondary succession of Chiloé Archipelago, Chile. After 62 d, lambs were slaughtered according to Chile’s meat industry standards. Fatty acid profile, RT-qPCR, and Western blot analyses from SCF and TF samples were performed. Although the mRNA expression levels of ACC, FAS, SCD1 and SREBP1c in SCF did not differ significantly between breeds (p > 0.05), a trend to higher mRNA expression of FAS and SREBP1c in TF from Chilota lambs was observed (p = 0.06). On the other hand, FAS levels in SCF were higher in Chilota than in Suffolk Down lambs (p < 0.02), although Suffolk Down showed higher fat contents and saturated fatty acid (SFA) proportions than Chilota lambs (p < 0.01). The FAS protein expression in TF was similar in both breeds (p > 0.05). Although the fat content was higher in Suffolk Down than in Chilota lambs (p < 0.01), the SFA proportions were similar in both breeds. Finally, it can be concluded that although mRNA expression of enzymes was similar in both breeds, there were differences in some protein levels in the SCF, partially related with the fatty acid profiles, thus affecting the selection of lamb breed either for human consumption or experimental purposes.
Bioactive Phenolic Compounds from the Agroindustrial Waste of Colombian Mango Cultivars ‘Sugar Mango’ and ‘Tommy Atkins’—An Alternative for Their Use and Valorization
Authors: Castro-Vargas Henry I. , Ballesteros Vivas Diego , Ortega Barbosa Jenny , Morantes Medina Sandra Johanna , Aristizabal Gutiérrez Fabio , Parada-Alfonso Fabián
Published: February 2019

The aim of this study was to explore the potential of the agroindustrial waste from two Colombian mango cultivars as sources of bioactive phenolic compounds. Phenolic extracts from mango waste (peels, seed coats, and seed kernels) of ‘sugar mango’ and ‘Tommy Atkins’ cultivars were obtained. The bioactive properties of the phenolic extracts were accessed by measuring their free radical scavenging activity and antioxidant effects against lipid oxidation in food products; moreover, their antiproliferative effects against some cell lines of human cancer were explored. It is observed that the agroindustrial waste studied provides promising sources of bioactive phenolics. ‘Sugar mango’ waste provided extracts with the highest antioxidant effect in food products and antiproliferative activity; these extracts reduced lipid oxidation and cell growth by more than 57% and 75%, respectively. The seed kernel from ‘sugar mango’ supplied the extract with the best bioactive qualities; in addition, some recognized bioactive phenolics (such as mangiferin and several galloyl glucosides) were observed in this extract and related with its properties. The results obtained suggest that ‘sugar mango’ waste may be considered a source of bioactive phenolics, with promising uses in food and pharmaceutical products. Thus, a suitable alternative for the use and valorization of agroindustrial waste from Colombian mango cultivars is presented.
Activation of Murine Immune Cells upon Co-culture with Plasma-treated B16F10 Melanoma Cells
Authors: Rödder Katrin , Moritz Juliane , Miller Vandana , Weltmann Klaus-Dieter , Metelmann Hans-Robert , Gandhirajan Rajesh , Bekeschus Sander
Published: February 2019

Recent advances in melanoma therapy increased median survival in patients. However, death rates are still high, motivating the need of novel avenues in melanoma treatment. Cold physical plasma expels a cocktail of reactive species that have been suggested for cancer treatment. High species concentrations can be used to exploit apoptotic redox signaling pathways in tumor cells. Moreover, an immune-stimulatory role of plasma treatment, as well as plasma-killed tumor cells, was recently proposed, but studies using primary immune cells are scarce. To this end, we investigated the role of plasma-treated murine B16F10 melanoma cells in modulating murine immune cells’ activation and marker profile. Melanoma cells exposed to plasma showed reduced metabolic and migratory activity, and an increased release of danger signals (ATP, CXCL1). This led to an altered cytokine profile with interleukin-1β (IL-1β) and CCL4 being significantly increased in plasma-treated mono- and co-cultures with immune cells. In T cells, plasma-treated melanoma cells induced extracellular signal-regulated Kinase (ERK) phosphorylation and increased CD28 expression, suggesting their activation. In monocytes, CD115 expression was elevated as a marker for activation. In summary, here we provide proof of concept that plasma-killed tumor cells are recognized immunologically, and that plasma exerts stimulating effects on immune cells alone.
Mutated Channelrhodopsins with Increased Sodium and Calcium Permeability
Authors: Duan Xiaodong , Nagel Georg , Gao Shiqiang
Published: February 2019

(1) Background: After the discovery and application of Chlamydomonas reinhardtii channelrhodopsins, the optogenetic toolbox has been greatly expanded with engineered and newly discovered natural channelrhodopsins. However, channelrhodopsins of higher Ca2+ conductance or more specific ion permeability are in demand. (2) Methods: In this study, we mutated the conserved aspartate of the transmembrane helix 4 (TM4) within Chronos and PsChR and compared them with published ChR2 aspartate mutants. (3) Results: We found that the ChR2 D156H mutant (XXM) showed enhanced Na+ and Ca2+ conductance, which was not noticed before, while the D156C mutation (XXL) influenced the Na+ and Ca2+ conductance only slightly. The aspartate to histidine and cysteine mutations of Chronos and PsChR also influenced their photocurrent, ion permeability, kinetics, and light sensitivity. Most interestingly, PsChR D139H showed a much-improved photocurrent, compared to wild type, and even higher Na+ selectivity to H+ than XXM. PsChR D139H also showed a strongly enhanced Ca2+ conductance, more than two-fold that of the CatCh. (4) Conclusions: We found that mutating the aspartate of the TM4 influences the ion selectivity of channelrhodopsins. With the large photocurrent and enhanced Na+ selectivity and Ca2+ conductance, XXM and PsChR D139H are promising powerful optogenetic tools, especially for Ca2+ manipulation.
A Cross-Dichroic-Prism-Based Multi-Perspective Digital Image Correlation System
Authors: Dan Xizuo , Li Junrui , Zhao Qihan , Sun Fangyuan , Wang Yonghong , Yang Lianxiang
Published: February 2019

A robust three-perspective digital image correlation (DIC) system based on a cross dichroic prism and single three charge-coupled device (3CCD) color cameras is proposed in this study. Images from three different perspectives are captured by a 3CCD camera using the cross dichroic prism and two planar mirrors. These images are then separated by different CCD channels to perform correlation calculation with an existing multi-camera DIC algorithm. The proposed system is considerably more compact than the conventional multi-camera DIC system. In addition, the proposed system has no loss of spatial resolution compared with the traditional single-camera DIC system. The principle and experimental setup of the proposed system is described in detail, and a series of tests is performed to validate the system. Experimental results show that the proposed system performs well in displacement, morphology, and strain measurement.
The Influence of Replacing Aggregates and Cement by LFS on the Corrosion of Steel Reinforcements
Authors: Prieto María Isabel , González María de las Nieves , Rodríguez Ángel , Cobo Alfonso
Published: February 2019

The aim of this study is to investigate the corrosion behavior of steel reinforcement embedded in mortar specimens in which both the aggregate and cement are partially replaced by ladle furnace slag (LFS) and different percentages of chloride ions by weight of cement are introduced into the mix at the time of kneading. The corrosion behavior was studied by using electrochemical techniques in order to evaluate the corrosion rate and the symptoms produced in steels of specimens with and without slag LFS. From the analysis of the results, it is concluded that the use of LFS in a partial replacement of aggregate and cement in mortar specimens does not compromise the behavior of the mortar with regard to corrosion of the steel reinforcement; consequently, partial replacement by LFS is fully feasible from this standpoint.
Drought in the Western United States: Its Connections with Large-Scale Oceanic Oscillations
Authors: Jiang Peng , Yu Zhongbo , Acharya Kumud
Published: February 2019

In this paper, we applied the Empirical Orthogonal Function (EOF) analysis on a drought index expressed as consecutive dry days (CDD) to identify the drought variability in western United States. Based on the EOF analysis, correlation maps were generated between the leading principle component (PC) of seasonal CDD and sea surface temperature (SST) anomalies to explore the dynamic context of the leading modes in CDD. The EOF analysis indicates that the spatiotemporal pattern of winter CDD is related to an integrated impact from El Niño–Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO), and Atlantic Multi-decadal Oscillation (AMO), while summer CDD is mainly controlled by PDO phases. We also calculated seasonal CDD anomalies during selected climatic phases to further evaluate the impacts of large-scale oceanic oscillation on the spatial pattern of droughts. We found that AMO+/PDO− will contribute to a consistent drought condition during the winter in the western United States. El Niño will bring a dry winter to the northern part of western United States while La Niña will bring a dry winter to the southern part. During El Niño years, the drought center changes with the type of El Niño events. Considering the future states of the examined ocean oscillations, we suggest possible drier than normal conditions in the western United States for upcoming decades, and moreover, an intensified drought for the coast areas of the north Pacific region and upper Mississippi River Basin.
Modeling Self-Healing Mechanisms in Coatings: Approaches and Perspectives
Authors: Javierre Etelvina
Published: February 2019

There is a wide range of self-healing mechanisms that provide the recovery of specific functionalities in coatings. Moreover, it is well known that computational simulation is a complementary tool that can help in the optimization and cost reduction of the experimental development of materials. This work critically discusses the current status of the models that are of interest for the advance of self-healing coatings, and proposes future paths of improvement.
Stenosis Indicators Applied to Patient-Specific Renal Arteries without and with Stenosis
Authors: Fuchs Alexander , Berg Niclas , Prahl Wittberg Lisa
Published: February 2019

Pulsatile flow in the abdominal aorta and the renal arteries of three patients was studied numerically. Two of the patients had renal artery stenosis. The aim of the study was to assess the use of four types of indicators for determining the risk of new stenosis after revascularization of the affected arteries. The four indicators considered include the time averaged wall shear stress (TAWSS), the oscillatory shear index (OSI), the relative reference time (RRT) and a power law model based in platelet activation modeling but applied to the endothelium, named endothelium activation indicator (EAI). The results show that the indicators can detect the existing stenosis but are less successful in the revascularized cases. The TAWSS and, more clearly, the EAI approach seem to be better in predicting the risk for stenosis relapse at the original location and close to the post-stenotic dilatation. The shortcomings of the respective indicators are discussed along with potential improvements to endothelial activation modeling and its use as an indicator for risks of restenosis.
Improved Tolerance for Onion Thrips and Iris Yellow Spot in Onion Plant Introductions after Two Selection Cycles
Authors: Singh Narinder , Cramer Christopher
Published: February 2019

Iris yellow spot (IYS), a disease caused by Iris yellow spot virus (IYSV) and spread by onion thrips, is a devastating disease of onion bulb and seed production. The development of onion germplasm resistant to IYS and/or thrips is crucial to onion production, since host plant resistance is unknown for both pests. During the summer of 2010 and 2012, plants with fewer IYS disease symptoms were selected from a screening of plant introduction accessions (PIs) and first-generation selections, respectively. The resulting progeny from these selected plants were evaluated during the summers of 2013 and 2014 for thrips numbers and IYS symptom expression, and compared with their respective original PIs and a susceptible check, ‘Rumba’. The field experiment was designed such that every plant in the field screening had an equal chance of being infected with IYSV. This study shows that variation for thrips and IYS existed among PIs and first- and second-generation selections. Even though not enough progress towards minimizing IYS severity was evident from this study, we did identify several lines with improved tolerance to onion thrips in first- and second-generation selections. The majority of the selected lines exhibited lower thrips and IYS severity compared to ‘Rumba’, which suggests that the progress towards developing insect- and ultimately disease-resistant germplasm can be achieved.
Integrating Island Spatial Information and Integer Optimization for Locating Maritime Search and Rescue Bases: A Case Study in the South China Sea
Authors: Zhou Xiao , Cheng Liang , Zhang Fangli , Yan Zhaojin , Ruan Xiaoguang , Min Kaifu , Li Manchun
Published: February 2019

Maritime search and rescue (SAR) operations are critical for ensuring safety at sea. Islands have been considered as feasible solutions for the construction of new maritime SAR bases to improve the capacity of SAR operations in remote sea areas. This paper proposes a new framework, based on island spatial information, for determining the optimal locations for maritime SAR bases. The framework comprises four steps. First, candidate islands for the construction of maritime SAR bases are selected. Second, the potential rescue demand is estimated by employing ship location data and marine incident data. In the third step, the response time from candidate islands to any site at sea is calculated, with explicit consideration of the impact of sea conditions on the ship’s speed. Fourth, the final island locations are proposed by solving the maximal covering location problem (MCLP). The proposed framework was applied to the South China Sea. The results showed that there would be a decrease of 1.09 h in terms of the mean access time for the South China Sea if the six selected island bases were constructed, whilst the primary coverage increased from 62.63% to 80.02% when using a 6-hour threshold. This new framework is expected to contribute to improvements in safety at sea and should be applicable to any sea area where the construction of island rescue bases is being considered.
Automatic Acquisition of Annotated Training Corpora for Test-Code Generation
Authors: Kacmajor Magdalena , Kelleher John D.
Published: February 2019

Open software repositories make large amounts of source code publicly available. Potentially, this source code could be used as training data to develop new, machine learning-based programming tools. For many applications, however, raw code scraped from online repositories does not constitute an adequate training dataset. Building on the recent and rapid improvements in machine translation (MT), one possibly very interesting application is code generation from natural language descriptions. One of the bottlenecks in developing these MT-inspired systems is the acquisition of parallel text-code corpora required for training code-generative models. This paper addresses the problem of automatically synthetizing parallel text-code corpora in the software testing domain. Our approach is based on the observation that self-documentation through descriptive method names is widely adopted in test automation, in particular for unit testing. Therefore, we propose synthesizing parallel corpora comprised of parsed test function names serving as code descriptions, aligned with the corresponding function bodies. We present the results of applying one of the state-of-the-art MT methods on such a generated dataset. Our experiments show that a neural MT model trained on our dataset can generate syntactically correct and semantically relevant short Java functions from quasi-natural language descriptions of functionality.
The Prognostic Significance of Puncture Timing to Survival of Arteriovenous Fistulas in Hemodialysis Patients: A Multicenter Retrospective Cohort Study
Authors: Lin Su-Ju , Tung Chun-Wu , Hsu Yung-Chien , Shih Ya-Hsueh , Wu Yi-Ling , Chou Tse-Chih , Chang Shu-Chen , Lin Chun-Liang
Published: February 2019

(1) Background: A functional shunt is critical to hemodialysis, but the ideal timing of shunt cannulation is still not established. In this study, we assessed the association between ideal puncture timing and shunt survival. (2) Methods: This retrospective cohort study using data from the Taiwan Health and Welfare database, which included 26885 hemodialysis patients with arteriovenous fistulas from 1 July 2008 to 30 June 2012. Fistulas were categorized by functional maturation time, defined as the time from the date of shunt construction to the first successful cannulation. Functional cumulative survival, measured as the duration from the first puncture to shunt abandonment, was mainly regarded. (3) Results: The fistulas created between 91 and 180 days prior to the first cannulation had significantly greater cumulative functional survival (HR 0.883; 95% CI 0.792–0.984), and there was no more benefit on their survival from waiting more than 180 days (HR 0.957; 95% CI 0.853–1.073) for shunt maturity. (4) Conclusions: Our results showed that to achieve better long-term shunt survivals, fistulas should be constructed at least 90 days before starting hemodialysis. Notably, there was no additional benefit on waiting more than 180 days prior to cannulation.
A Longitudinal Examination of the Social-Ecological Correlates of Exercise in Men and Women Following Cardiac Rehabilitation
Authors: Moghei Mahshid , Reid Robert D. , Wooding Evyanne , Melo Ghisi Gabriela , Pipe Andrew , Chessex Caroline , Prince Stephanie A. , Blanchard Chris , Oh Paul , Grace Sherry L.
Published: February 2019

Cardiac patients who engage in ≥150 min of moderate- to vigorous-intensity physical activity (MVPA)/week have lower mortality, yet MVPA declines even following cardiac rehabilitation (CR), and is lower in women. A randomized trial of nine socioecological theory-based exercise facilitation contacts over 50 weeks versus usual care (1:1 parallel arms) was undertaken (NCT01658683). The tertiary objective, as presented in this paper, was to test whether the intervention impacted socioecological elements, and in turn their association with MVPA. The 449 participants wore an accelerometer and completed questionnaires post-CR, and 26, 52 and 78 weeks later. At 52 weeks, exercise task self-efficacy was significantly greater in the intervention arm (p = 0.01), but no other differences were observed except more encouragement from other cardiac patients at 26 weeks (favoring controls). Among women adherent to the intervention, the group in whom the intervention was proven effective, physical activity (PA) intentions at 26 weeks were significantly greater in the intervention arm (p = 0.04), with no other differences. There were some differences in socioecological elements associated with MVPA by arm. There were also some differences by sex, with MVPA more often associated with exercise benefits/barriers in men, versus with working and the physical environment in women.
Cardiovascular Health Benefits of Exercise Training in Persons Living with Type 1 Diabetes: A Systematic Review and Meta-Analysis
Authors: Wu Nana , Bredin Shannon S.D. , Guan Yanfei , Dickinson Kyra , Kim David D. , Chua Zongyu , Kaufman Kai , Warburton Darren E.R.
Published: February 2019

Exercise is advocated in the management of type 1 diabetes (T1D), but the effects of different forms of exercise training on cardiovascular risk factors in T1D still remain unclear. The aim of this study was to conduct a systematic review and meta-analysis on exercise training for cardiovascular risk factors in T1D. Six electronic databases were systematically searched for randomized or non-randomized controlled studies reporting associations between exercise training and cardiovascular risk factors in T1D. Weighted mean differences (WMD) of each cardiovascular risk factor between exercise groups and control groups were calculated using a random effects model. A total of 24 studies reported the effects of exercise training on cardiovascular risk factors. Exercise training increased maximal aerobic power (3.01 mL·kg−1·min−1, 95% confidence interval, CI, 0.94 to 6.38) and reduced glycated hemoglobin (HbA1c; −0.45%, 95% CI −0.73 to −0.17), daily insulin dosage (−0.88 U·kg−1, 95% CI −1.27 to −0.48), and total cholesterol (−0.38 mmol·L−1, 95% CI −0.71 to −0.04). Exercise training did not lead to consistent changes in body mass index (BMI), blood pressure, triglycerides, high-density lipoprotein cholesterol (HDL-C), or low-density lipoprotein cholesterol (LDL-C). In persons living with T1D, exercise training is associated with a beneficial cardiovascular profile, including improvements in lipid profile, glycemic control (decreased daily insulin dosage and HbA1c), and aerobic fitness.
In-Situ Imaging of Molten High-Entropy Alloys Using Cold Neutrons
Authors: Derimow Nicholas , Santodonato Louis J. , MacDonald Benjamin E. , Le Bryan , Lavernia Enrique J. , Abbaschian Reza
Published: February 2019

Real-time neutron imaging was utilized to produce a movie-like series of radiographs for in-situ observation of the remixing of liquid state immiscibility that occurs in equiatomic CoCrCu with the addition of Ni. A previous neutron imaging study demonstrated that liquid state immiscibility can be observed in-situ for the equiatomic CoCrCu alloy. In this follow-up study, equiatomic buttons of CoCrCu were placed alongside small Ni buttons inside an alumina crucible in a high-temperature vacuum furnace. The mass of the Ni buttons was specifically selected such that when melted in the same crucible as the CoCrCu buttons, the overall composition would become equiatomic CoCrCuNi. Neutron imaging was simultaneously carried out to capture 10 radiographs in 20 °C steps from 1000 °C to 1500 °C and back down to 1000 °C. This, in turn, produced a movie-like series of radiographs that allow for the observation of the buttons melting, the transition from immiscible to miscible as Ni is alloyed into the CoCrCu system, and solidification. This novel imaging process showed the phase-separated liquids remixing into a single-phase liquid when Ni dissolves into the melt, which makes this technique crucial for understanding the liquid state behavior of these complex alloy systems. As metals are not transparent to X-ray imaging techniques at this scale, neutron imaging of melting and solidification allows for the observation of liquid state phase changes in real time. Thermodynamic calculations of the isopleth for CoCrCuNix were carried out to compare the observed results to the predictions resulting from the current Thermo-Calc TCHEA3 thermodynamic database. The calculations show a very good agreement with the experimental results, as the calculations indicate that the CoCrCuNix alloy solidifies from a single-phase liquid when x ≥ 0.275, which is close to the nominal concentration of the CoCrCuNi alloy (x = 0.25). The neutron imaging shows that the solidification of CoCrCuNi results from a single-phase liquid. This is evident as no changes in the neutron attenuation were observed during the solidification of the CoCrCuNi alloy.
A Hamiltonian Surface-Shaping Approach for Control System Analysis and the Design of Nonlinear Wave Energy Converters
Authors: Darani Shadi , Abdelkhalik Ossama , Robinett Rush D. , Wilson David
Published: February 2019

The dynamic model of Wave Energy Converters (WECs) may have nonlinearities due to several reasons such as a nonuniform buoy shape and/or nonlinear power takeoff units. This paper presents the Hamiltonian Surface-Shaping (HSS) approach as a tool for the analysis and design of nonlinear control of WECs. The Hamiltonian represents the stored energy in the system and can be constructed as a function of the WEC’s system states, its position, and velocity. The Hamiltonian surface is defined by the energy storage, while the system trajectories are constrained to this surface and determined by the power flows of the applied non-conservative forces. The HSS approach presented in this paper can be used as a tool for the design of nonlinear control systems that are guaranteed to be stable. The optimality of the obtained solutions is not addressed in this paper. The case studies presented here cover regular and irregular waves and demonstrate that a nonlinear control system can result in a multiple fold increase in the harvested energy.
Making Molecules with Clay: Layered Double Hydroxides, Pentopyranose Nucleic Acids and the Origin of Life
Authors: Bernhardt Harold S.
Published: February 2019

A mixture of sugar diphosphates is produced in reactions between small aldehyde phosphates catalysed by layered double hydroxide (LDH) clays under plausibly prebiotic conditions. A subset of these, pentose diphosphates, constitute the backbone subunits of nucleic acids capable of base pairing, which is not the case for the other products of these LDH-catalysed reactions. Not only that, but to date no other polymer found capable of base pairing—and therefore information transfer—has a backbone for which its monomer subunits have a plausible prebiotic synthesis, including the ribose-5-phosphate backbone subunit of RNA. Pentose diphosphates comprise the backbone monomers of pentopyranose nucleic acids, some of the strongest base pairing systems so far discovered. We have previously proposed that the first base pairing interactions were between purine nucleobase precursors, and that these were weaker and less specific than standard purine-pyrimidine interactions. We now propose that the inherently stronger pairing of pentopyranose nucleic acids would have compensated for these weaker interactions, and produced an informational polymer capable of undergoing nonenzymatic replication. LDH clays might also have catalysed the synthesis of the purine nucleobase precursors, and the polymerization of pentopyranose nucleotide monomers into oligonucleotides, as well as the formation of the first lipid bilayers.
Ag2S Quantum Dots Based on Flower-like SnS2 as Matrix and Enhanced Photocatalytic Degradation
Authors: Zhao Wenhua , Wei Zhiqiang , Ma Long , Liang Jiahao , Zhang Xudong
Published: February 2019

Ag2S quantum dots were dispersed on the surface of SnS2 nanoflowers forming a heterojunction via in-situ ion exchange to improve photocatalytic degradation of RhB. All samples exhibit the hexagonal wurtzite structure. The size of Ag2S@SnS2 composites are ~ 1.5 μm flower-like with good crystallinity. Meanwhile, the Eg of 3% Ag2S@SnS2 is close to that of pure SnS2. Consequently, the 3% Ag2S@SnS2 composite displays the excellent photocatalytic performance under simulated sunlight irradiation with good cycling stability, compared to the pure SnS2 and other composites. Due to the blue and yellow luminescence quenching, the photogenerated electrons and holes is effectively separated in the 3% Ag2S@SnS2 sample. Especially, the hydroxyl radicals and photogenerated holes are main active species.
A Partial-Consensus Posterior-Aggregation FAHP Method—Supplier Selection Problem as an Example
Authors: Wang Yu-Cheng , Chen Tin-Chih
Published: February 2019

Existing fuzzy analytic hierarchy process (FAHP) methods usually aggregate the fuzzy pairwise comparison results produced by multiple decision-makers (DMs) rather than the fuzzy weights estimations. This is problematic because fuzzy pairwise comparison results are subject to uncertainty and lack consensus. To address this problem, a partial-consensus posterior-aggregation FAHP (PCPA-FAHP) approach is proposed in this study. The PCPA-FAHP approach seeks a partial consensus among most DMs instead of an overall consensus among all DMs, thereby increasing the possibility of reaching a consensus. Subsequently, the aggregation result is defuzzified using the prevalent center-of-gravity method. The PCPA-FAHP approach was applied to a supplier selection problem to validate its effectiveness. According to the experimental results, the PCPA-FAHP approach not only successfully found out the partial consensus among the DMs, but also shrunk the widths of the estimated fuzzy weights to enhance the precision of the FAHP analysis.
A Multi-Objective DV-Hop Localization Algorithm Based on NSGA-II in Internet of Things
Authors: Wang Penghong , Xue Fei , Li Hangjuan , Cui Zhihua , Xie Liping , Chen Jinjun
Published: February 2019

Locating node technology, as the most fundamental component of wireless sensor networks (WSNs) and internet of things (IoT), is a pivotal problem. Distance vector-hop technique (DV-Hop) is frequently used for location node estimation in WSN, but it has a poor estimation precision. In this paper, a multi-objective DV-Hop localization algorithm based on NSGA-II is designed, called NSGA-II-DV-Hop. In NSGA-II-DV-Hop, a new multi-objective model is constructed, and an enhanced constraint strategy is adopted based on all beacon nodes to enhance the DV-Hop positioning estimation precision, and test four new complex network topologies. Simulation results demonstrate that the precision performance of NSGA-II-DV-Hop significantly outperforms than other algorithms, such as CS-DV-Hop, OCS-LC-DV-Hop, and MODE-DV-Hop algorithms.
The Extremal Solution To Conformable Fractional Differential Equations Involving Integral Boundary Condition
Authors: Meng Shuman , Cui Yujun
Published: February 2019

In this article, by using the monotone iterative technique coupled with the method of upper and lower solution, we obtain the existence of extremal iteration solutions to conformable fractional differential equations involving Riemann-Stieltjes integral boundary conditions. At the same time, the comparison principle of solving such problems is investigated. Finally, an example is given to illustrate our main results. It should be noted that the conformal fractional derivative is essentially a modified version of the first-order derivative. Our results show that such known results can be translated and stated in the setting of the so-called conformal fractional derivative.
Application of Exponential Jensen Picture Fuzzy Divergence Measure in Multi-Criteria Group Decision Making
Authors: Zeng Shouzhen , Asharf Shahzaib , Arif Muhammad , Abdullah Saleem
Published: February 2019

A divergence measure plays a crucial part in discriminating two probability distributions and drawing inferences constructed on such discrimination. The intention of this study is to propose such a divergence measure based on Jensen inequality and exponential entropy in the settings of probability theory. Further, the idea has been generalized to fuzzy sets to familiarize a novel picture fuzzy divergence measure. Besides proposing the validity, some of its key properties are also deliberated. Finally, two illustrative examples are solved based on the proposed picture fuzzy divergence measure which shows the expediency and effectiveness of the proposed approach.
Use of Magnetic Resonance Imaging in Evaluating Fetal Brain and Abdomen Malformations during Pregnancy
Authors: Valevičienė Nomeda Rima , Varytė Guoda , Zakarevičienė Jolita , Kontrimavičiūtė Eglė , Ramašauskaitė Diana , Rutkauskaitė-Valančienė Dileta
Published: February 2019

Magnetic resonance imaging (MRI) is used as a clarifying technique after a high-resolution ultrasound examination during pregnancy. Combining ultrasound with MRI, additional diagnostic information is obtained or ultrasound diagnosis is frequently corrected. High spatial resolution provides accurate radiological imaging of internal organs and widens possibilities for detecting perinatal development disorders. The safety of MRI and the use of intravenous contrast agent gadolinium are discussed in this article. There is no currently available evidence that MRI is harmful to the fetus, although not enough research has been carried out to prove enduring safety. MRI should be performed when the benefit outweighs the potential side effects. The narrative review includes several clinical cases of fetal MRI performed in Vilnius University Hospital Santaros Clinics.
A Quick Cycle Time Sensitivity Analysis of Boron Steel Hot Stamping
Authors: Fernández Borja , González Beatriz , Artola Garikoitz , López de Lacalle Norberto , Angulo Carlos
Published: February 2019

Several vehicle platforms involving the hot stamping of manufactured parts are launched every year. Mass production represents a key step in the manufacturing process of an actual hot stamping part. In this step, the cycle time (consisting of cooling time (t1) and handling time (t2) components) must be optimized. During t1, the stamping tool (punch and die) is closed, for cooling of the part. The t2 components (i.e., inlet transfer time, press forming time (closing and opening), and outlet transfer time) define the production output that ensures process performance. However, cost is the main driver in automotive applications. Here, a cycle-time calculation based on the design of experiments (DOE) is proposed for formulating cost-effective formulas. An iterative one-dimensional heat transfer model for each DOE step is set up to simulate 10 hot stamping cycles; the part temperature after quenching in cycle number 10 (where steady conditions are achieved) was selected as the process output variable to be controlled in the DOE. Several DOE variables were considered. The DOE results were employed for the proposal of a simplified formula, which helps in assessing the cycle time with its excellent trade-off between calculation cost and reliability. The formula was validated by laboratory tests.
A pXRF In Situ Study of 16th–17th Century Fresco Paints from Sviyazhsk (Tatarstan Republic, Russian Federation)
Authors: Khramchenkova Rezida , Ionescu Corina , Sitdikov Airat , Kaplan Polina , Gál Ágnes , Gareev Bulat
Published: February 2019

Twenty frescoes from “The Assumption” Cathedral located in the island town of Sviyazhsk (Tatarstan Republic, Russian Federation)—dated back to the times of Tsar Ivan IV “the Terrible”—were chemically analyzed in situ with a portable X-ray fluorescence (pXRF) spectrometer. The investigation focused on identifying the pigments and their combinations in the paint recipes. One hundred ninety-three micropoints randomly chosen from the white, yellow, orange, pink, brown, red, grey, black, green, and blue areas were measured for major and minor elements. The compositional types separated within each color indicate different recipes. The statistical processing of the data unveiled the most important oxides (CaO, MgO, Fe2O3, PbO, SO3, Sb2O3, Al2O3, SiO2, and P2O5) and their relationships. The results allowed to infer the mineral composition of the paints, and, hence, the recipes used by the Russian artisans. Slaked lime and slaked dolomitic lime mixed with variable amounts of “antimony white” and “bone white” were used for white, pink, yellow, and orange paints and for preparing a basic batch for all other colors. Mostly yellow ochre, red ochre, and lead minerals, and occasionally blue ochre, green earth, realgar, orpiment, bone black, galena, stibnite, and magnetite were the pigments involved in various amounts in preparing the paints.
Geostatistical Estimation of Multi-Domain Deposits with Transitional Boundaries: A Sensitivity Study for the Sechahun Iron Mine
Authors: Kasmaee Sara , Raspa Giuseppe , de Fouquet Chantal , Tinti Francesco , Bonduà Stefano , Bruno Roberto
Published: February 2019

In mineral resource estimation, identification of the geological domains to be used for modeling, and the type of boundaries dividing them, is a major concern. Generally, the variables within a domain are estimated with an assumption of the hard boundaries (sharp contact). However, in many cases, the geologic structures that generate a deposit are transitional (overlapping of several geologic domains). Consequently, boundary identification of the geological domains is essential for an accurate estimate of resources. This paper considers a real application to examine whether the addition of geologic information benefits grade estimation in the presence of transitional boundaries. Results proved that the accuracy of the grade estimation can be improved by adding geological information and there is a significant sensitivity in grade estimation results in the existence of transitional boundaries.
Cleaner Extraction of Lead from Complex Lead-Containing Wastes by Reductive Sulfur-Fixing Smelting with Low SO2 Emission
Authors: Li Yun , Yang Shenghai , Lin Wenrong , Taskinen Pekka , He Jing , Wang Yuejun , Shi Junjie , Chen Yongming , Tang Chaobo , Jokilaakso Ari
Published: February 2019

A novel and cleaner process for lead and silver recycling from multiple lead-containing wastes, e.g., lead ash, lead sludge, lead slag, and ferric sludge, by reductive sulfur-fixing smelting was proposed. In this process, coke and iron-containing wastes were employed as reductive agent and sulfur-fixing agent, respectively. A Na2CO3-Na2SO4 mixture was added as flux. The feasibility of this process was detected from thermodynamic and experimental perspectives. The influence of Fe/SiO2 and CaO/SiO2, composition of the molten salt, coke addition, smelting temperature, and smelting time on direct Pb recovery and sulfur-fixation efficiency were investigated. The optimal process conditions were determined as follows: WCoke = 15% WPb wastes, W Na 2 CO 3 / W Na 2 SO 4 = 0.7/0.3, Fe/SiO2 = 1.10, CaO/SiO2 = 0.30, smelting temperature 1200 °C, and smelting time 2 h, where W represents weight. Under these optimum conditions, 92.4% Pb and 98.8% Ag were directly recovered in crude lead bullion in one step treatment, and total 98.6% sulfur was fixed. The generation and emissions of SO2 can be avoided. The main phases in ferrous matte obtained were FeS, NaFeS2, Fe2Zn3S5, and a little entrained Pb. The slag was a FeO-SiO2-CaO-Na2O quaternary melt.
Enhanced N-doped Porous Carbon Derived from KOH-Activated Waste Wool: A Promising Material for Selective Adsorption of CO2/CH4 and CH4/N2
Authors: Li Yao , Xu Ran , Wang Binbin , Wei Jianping , Wang Lanyun , Shen Mengqi , Yang Juan
Published: February 2019

Separation of impurities (CO2 and N2) from CH4 is an important issue for natural gas alternatives (such as coalbed gas, biogas, and landfill gas) upgrading. It is notably challenging to synthesize high N-doped porous carbon with an appropriate porous structure. In this work, high N content (14.48 wt %) porous carbon with micropore size of 0.52 and 1.2 nm and specific surface area of 862 m2 g−1 has been synthesized from potassium hydroxide (KOH) activated waste wool upon the urea modification. Pure component adsorption isotherms of CO2, CH4, and N2 are systematically measured on this enhanced N-doped porous carbon at 0 and 25 °C, up to 1 bar, to evaluate the gases adsorption capability, and correlated with the Langmuir model. These data are used to estimate the separation selectivities for binary mixtures of CO2/CH4 and CH4/N2 at different mixing ratios according to the ideal adsorbed solution theory (IAST) model. At an ambient condition of 25 °C and 1 bar, the predicted selectivities for equimolar CO2/CH4 and CH4/N2 are 3.19 and 7.62, respectively, and the adsorption capacities for CO2, CH4, and N2 are 2.91, 1.01, and 0.13 mmol g−1, respectively. This report introduces a simple pathway to obtain enhanced N-doped porous carbon with large adsorption capacities for gas separation of CO2/CH4 and CH4/N2.
Nano-Cellulose/MOF Derived Carbon Doped CuO/Fe3O4 Nanocomposite as High Efficient Catalyst for Organic Pollutant Remedy
Authors: Lu Hailong , Zhang Lili , Ma Jinxia , Alam Nur , Zhou Xiaofan , Ni Yonghao
Published: February 2019

Metal–organic framework (MOF)-based derivatives are attracting increased interest in various research fields. In this study, nano-cellulose MOF-derived carbon-doped CuO/Fe3O4 nanocomposites were successfully synthesized via direct calcination of magnetic Cu-BTC MOF (HKUST-1)/Fe3O4/cellulose microfibril (CMF) composites in air. The morphology, structure, and porous properties of carbon-doped CuO/Fe3O4 nanocomposites were characterized using SEM, TEM, powder X-ray diffraction (PXRD), X-ray photoelectron spectroscopy (XPS), and vibrating sample magnetometry (VSM). The results show that the as-prepared nanocomposite catalyst is composed of Fe3O4, CuO, and carbon. Compared to the CuO/Fe3O4 catalyst from HKUST-1/Fe3O4 composite and CuO from HKUST-1, this carbon-doped CuO/Fe3O4 nanocomposite catalyst shows better catalytic efficiency in reduction reactions of 4-nitrophenol (4-NP), methylene blue (MB), and methyl orange (MO) in the presence of NaBH4. The enhanced catalytic performance of carbon-doped CuO/Fe3O4 is attributed to effects of carbon preventing the aggregation of CuO/Fe3O4 and providing high surface-to-volume ratio and chemical stability. Moreover, this nanocomposite catalyst is readily recoverable using an external magnet due to its superparamagnetic behavior. The recyclability/reuse of carbon-doped CuO/Fe3O4 was also investigated.
Plasma-Based Synthesis and Modification of Nanomaterials
Authors: Pohl Pawel
Published: February 2019

This Special Issue of Nanomaterials, including nine original research works [...]