bluuebunny/crossref_metadata_2025 huggingface dataset:
Energy, Trade, Urbanization and Environmental Degradation Nexus in Sri Lanka: Bounds Testing Approach
Authors: Gasimli Oruj , Haq Ihtisham ul , Naradda Gamage Sisira Kumara , Shihadeh Fadi , Rajapakshe Prasanna Sisira Kumara , Shafiq Muhammad
Published: May 2019

This study examines the nexus between energy, trade, urbanization and environmental degradation in Sri Lanka. The time series data has been checked for unit root problem along with unknown structural break. The bounds testing approach confirms the long-term relationship among carbon emissions, energy consumption, income, trade openness, and urbanization in the presence of structural break. The results of the study do not confirm the presence of the EKC (Environmental Kuznets Curve) hypothesis in Sri Lanka. This study finds that energy consumption leads to carbon emissions in both the long term and the short term. Trade openness is degrading environmental quality, as trade is responsible for the accumulation of carbon emissions in the atmosphere. The results of the study confirm that urbanization has been found to have significant and negative effect on carbon emissions. The study finds that the model is in equilibrium and the model will return to equilibrium from any external shock in less than two years. Policy measures are recommended for sustainable environment of the island.
Smart-Sensors to Estimate Insulation Health in Induction Motors via Analysis of Stray Flux
Authors: Zamudio-Ramirez Israel , Osornio-Rios Roque Alfredo , Trejo-Hernandez Miguel , Romero-Troncoso Rene de Jesus , Antonino-Daviu Jose Alfonso
Published: May 2019

Induction motors (IMs) are essential components in industrial applications. These motors have to perform numerous tasks under a wide variety of conditions, which affects performance and reliability and gradually brings faults and efficiency losses over time. Nowadays, the industrial sector demands the necessary integration of smart-sensors to effectively diagnose faults in these kinds of motors before faults can occur. One of the most frequent causes of failure in IMs is the degradation of turn insulation in windings. If this anomaly is present, an electric motor can keep working with apparent normality, but factors such as the efficiency of energy consumption and mechanical reliability may be reduced considerably. Furthermore, if not detected at an early stage, this degradation could lead to the breakdown of the insulation system, which could in turn cause catastrophic and irreversible failure to the electrical machine. This paper proposes a novel methodology and its application in a smart-sensor to detect and estimate the healthiness of the winding insulation in IMs. This methodology relies on the analysis of the external magnetic field captured by a coil sensor by applying suitable time-frequency decomposition (TFD) tools. The discrete wavelet transform (DWT) is used to decompose the signal into different approximation and detail coefficients as a pre-processing stage to isolate the studied fault. Then, due to the importance of diagnosing stator winding insulation faults during motor operation at an early stage, this proposal introduces an indicator based on wavelet entropy (WE), a single parameter capable of performing an efficient diagnosis. A smart-sensor is able to estimate winding insulation degradation in IMs using two inexpensive, reliable, and noninvasive primary sensors: a coil sensor and an E-type thermocouple sensor. The utility of these sensors is demonstrated through the results obtained from analyzing six similar IMs with differently induced severity faults.
Multi-Criteria Decision-Making under mHF ELECTRE-I and HmF ELECTRE-I
Authors: Adeel Arooj , Akram Muhammad , Koam Ali N.A.
Published: May 2019

In a few years, hesitant fuzzy sets (HFSs) have had an impact on several different areas of decision science. However, a number of researches have utilized the Elimination and choice translating reality (ELECTRE) methods to determine the multi-criteria decision-making (MCDM) problems with hesitant information. The aim of this research article is to develop new multi-criteria group decision-making (MCGDM) methods, such as the m-polar hesitant fuzzy ELECTRE-I (mHF ELECTRE-I) method and hesitant m-polar fuzzy ELECTRE-I (HmF ELECTRE-I) method. Proposed MCGDM techniques based on the hybrid models, m-polar hesitant fuzzy sets (mHFS-sets) and hesitant m-polar fuzzy sets (HmF-sets), which are the natural generalizations of HFSs and m-polar fuzzy sets (mF sets). These models enable us to deal with multipolar information under hesitancy. We use the proposed methods to deal the complex problems in which the membership degree of an element of given set uses the m different numeric and fuzzy values, to rank all the alternatives and to determine the best alternative. We present two practical examples that illustrate the procedure of the proposed methods. We also discuss the differences and comparative analysis of the proposed methods. Finally, we develop an algorithm that implements our decision-making procedures by using computer programming.
Elimination of Common Mode Voltage in Three-To-Six-Phase Matrix Converter
Authors: Rząsa Janina , Sztajmec Elżbieta
Published: May 2019

The matrix converter (MC) is the n-phase input and m-phase output power electronic system. To synthesis the controllable sinusoidal output voltage and input current with controllable input displacement angle, the pulse width modulation method (PWM) is used in the MC. During the modulation process a problem of the common mode voltage (CMV) exists. The elimination of the CMV in three-to-six-phase MC by usage of only rotating voltage space vectors is analyzed in the paper. The carrier based implementation of the space vector modulation (SVM) with Venturini modulation functions is applied to the control of the three-to-six-phase MC. Entire elimination of the CMV in three-to-six-phase MC is presented in the paper. The simulation and experiment results confirm utility of the proposed modulation method.
Robust Speed Control of PMSM Using Sliding Mode Control (SMC)—A Review
Authors: Mohd Zaihidee Fardila , Mekhilef Saad , Mubin Marizan
Published: May 2019

Permanent magnet synchronous motors (PMSMs) are known as highly efficient motors and are slowly replacing induction motors in diverse industries. PMSM systems are nonlinear and consist of time-varying parameters with high-order complex dynamics. High performance applications of PMSMs require their speed controllers to provide a fast response, precise tracking, small overshoot and strong disturbance rejection ability. Sliding mode control (SMC) is well known as a robust control method for systems with parameter variations and external disturbances. This paper investigates the current status of implementation of sliding mode control speed control of PMSMs. Our aim is to highlight various designs of sliding surface and composite controller designs with SMC implementation, which purpose is to improve controller’s robustness and/or to reduce SMC chattering. SMC enhancement using fractional order sliding surface design is elaborated and verified by simulation results presented. Remarkable features as well as disadvantages of previous works are summarized. Ideas on possible future works are also discussed, which emphasize on current gaps in this area of research.
Comparative Analysis of Different Methodologies Used to Estimate the Ground Thermal Conductivity in Low Enthalpy Geothermal Systems
Authors: Sáez Blázquez Cristina , Martín Nieto Ignacio , Farfán Martín Arturo , González-Aguilera Diego , Carrasco García Pedro
Published: May 2019

In ground source heat pump systems, the thermal properties of the ground, where the well field is planned to be located, are essential for proper geothermal design. In this regard, estimation of ground thermal conductivity has been carried out by the implementation of different techniques and laboratory tests. In this study, several methods to obtain the thermal properties of the ground are applied in order to compare them with the reference thermal response test (TRT). These methods (included in previous research works) are carried out in the same geological environment and on the same borehole, in order to make an accurate comparison. All of them provide a certain value for the thermal conductivity of the borehole. These results are compared to the one obtained from the TRT carried out in the same borehole. The conclusions of this research allow the validation of alternative solutions based on the use of a thermal conductive equipment and the application of geophysics techniques. Seismic prospecting has been proven as a highly recommendable indicator of the thermal conductivity of a borehole column, obtaining rate errors of below 1.5%.
A Potential Field Description for Gravity-Driven Film Flow over Piece-Wise Planar Topography
Authors: Scholle Markus , Gaskell Philip H. , Marner Florian
Published: May 2019

Models based on a potential field description and corresponding first integral formulation, embodying a reduction of the associated dynamic boundary condition at a free surface to one of a standard Dirichlet-Neumann type, are used to explore the problem of continuous gravity-driven film flow down an inclined piece-wise planar substrate in the absence of inertia. Numerical solutions of the first integral equations are compared with analytical ones from a linearised form of a reduced equation set resulting from application of the long-wave approximation. The results obtained are shown to: (i) be in very close agreement with existing, comparable experimental data and complementary numerical predictions for isolated step-like topography available in the open literature; (ii) exhibit the same qualitative behaviour for a range of Capillary numbers and step heights/depths, becoming quantitively similar when both are small. A novel outcome of the formulation adopted is identification of an analytic criteria enabling a simple classification procedure for specifying the characteristic nature of the free surface disturbance formed; leading subsequently to the generation of a related, practically relevant, characteristic parameter map in terms of the substrate inclination angle and the Capillary number of the associated flow.
Nanomachinery Organizing Release at Neuronal and Ribbon Synapses
Authors: Chakrabarti Rituparna , Wichmann Carolin
Published: May 2019

A critical aim in neuroscience is to obtain a comprehensive view of how regulated neurotransmission is achieved. Our current understanding of synapses relies mainly on data from electrophysiological recordings, imaging, and molecular biology. Based on these methodologies, proteins involved in a synaptic vesicle (SV) formation, mobility, and fusion at the active zone (AZ) membrane have been identified. In the last decade, electron tomography (ET) combined with a rapid freezing immobilization of neuronal samples opened a window for understanding the structural machinery with the highest spatial resolution in situ. ET provides significant insights into the molecular architecture of the AZ and the organelles within the presynaptic nerve terminal. The specialized sensory ribbon synapses exhibit a distinct architecture from neuronal synapses due to the presence of the electron-dense synaptic ribbon. However, both synapse types share the filamentous structures, also commonly termed as tethers that are proposed to contribute to different steps of SV recruitment and exocytosis. In this review, we discuss the emerging views on the role of filamentous structures in SV exocytosis gained from ultrastructural studies of excitatory, mainly central neuronal compared to ribbon-type synapses with a focus on inner hair cell (IHC) ribbon synapses. Moreover, we will speculate on the molecular entities that may be involved in filament formation and hence play a crucial role in the SV cycle.
Non-Coding RNA Networks in ALK-Positive Anaplastic-Large Cell Lymphoma
Authors: Fuchs Steffen , Naderi Julian , Meggetto Fabienne
Published: May 2019

Non-coding RNAs (ncRNAs) are essential regulators of gene expression. In recent years, it has become more and more evident that the different classes of ncRNAs, such as micro RNAs, long non-coding RNAs and circular RNAs are organized in tightly controlled networks. It has been suggested that deregulation of these networks can lead to disease. Several studies show a contribution of these so-called competing-endogenous RNA networks in various cancer entities. In this review, we highlight the involvement of ncRNA networks in anaplastic-large cell lymphoma (ALCL), a T-cell neoplasia. A majority of ALCL cases harbor the molecular hallmark of this disease, a fusion of the anaplastic lymphoma kinase (ALK) gene with the nucleophosmin (NPM, NPM1) gene leading to a permanently active kinase that promotes the malignant phenotype. We have focused especially on ncRNAs that are regulated by the NPM-ALK fusion gene and illustrate how their deregulation contributes to the pathogenesis of ALCL. Lastly, we summarize the findings and point out potential therapeutic implications.
SpotLight Proteomics—A IgG-Enrichment Phenotype Profiling Approach with Clinical Implications
Authors: Lundström Susanna L. , Heyder Tina , Wiklundh Emil , Zhang Bo , Eklund Anders , Grunewald Johan , Zubarev Roman A.
Published: May 2019

Sarcoidosis is a systemic interstitial lung disease of unknown aetiology. Less invasive diagnostics are needed to decipher disease pathology and to distinguish sub-phenotypes. Here we test if SpotLight proteomics, which combines de novo MS/MS sequencing of enriched IgG and co-extracted proteins with subsequent label-free quantification of new and known peptides, can differentiate controls and sarcoidosis phenotypes (Löfgrens and non-Löfgrens syndrome, LS and nonLS). Intra-individually matched IgG enriched from serum and bronchial lavage fluid (BALF) from controls (n = 12), LS (n = 11) and nonLS (n = 12) were investigated. High-resolution mass-spectrometry SpotLight proteomics and uni- and multivariate-statistical analyses were used for data processing. Major differences were particularly observed in control-BALF versus sarcoidosis-BALF. However, interestingly, information obtained from BALF profiles was still present (but less prominent) in matched serum profiles. By using information from orthogonal partial least squares discriminant analysis (OPLS-DA) differentiating 1) sarcoidosis-BALF and control-BALF and 2) LS-BALF vs. nonLS-BALF, control-serum and sarcoidosis-serum (p = 0.0007) as well as LS-serum and nonLS-serum (p = 0.006) could be distinguished. Noteworthy, many factors prominent in identifying controls and patients were those associated with Fc-regulation, but also features from the IgG-Fab region and novel peptide variants. Differences between phenotypes were mostly IgG-specificity related. The results support the analytical utility of SpotLight proteomics which prospectively have potential to differentiate closely related phenotypes from a simple blood test.
Expression of Musashi-1 During Osteogenic Differentiation of Oral MSC: An In Vitro Study
Authors: Padial-Molina Miguel , de Buitrago Juan G. , Sainz-Urruela Raquel , Abril-Garcia Dario , Anderson Per , O’Valle Francisco , Galindo-Moreno Pablo
Published: May 2019

Background: Musashi-1 (MSI1) is a negative regulator of mesenchymal stromal cell (MSC) differentiation which in turn favors cell proliferation. However, little is known about its expression by MSC from the oral cavity and in the context of osteogenic differentiation. Aim: The aim of this study was to analyze the expression of MSI1 in the context of osteogenic differentiation of MSC derived from the oral cavity. Material/methods: For this in vitro study, MSC were isolated from six different origins of the oral cavity. They were extensively characterized in terms of proliferative and clonogenicity potential, expression of stemness genes (MYC, NANOG, POU5F1, and SOX2), expression of surface markers (CD73, CD90, CD105, CD14, CD31, CD34, and CD45) and adipo-, chondro- and osteogenic differentiation potential. Then, osteogenic differentiation was induced and the expression of MSI1 mRNA and other relevant markers of osteogenic differentiation, including RUNX2 and Periostin, were also evaluated. Results: Cell populations from the alveolar bone (pristine or previously grafted with xenograft), dental follicle, dental germ, dental pulp, and periodontal ligament were obtained. The analysis of proliferative and clonogenicity potential, expression of the stemness genes, expression of surface markers, and differentiation potential showed similar characteristics to those of previously published MSC from the umbilical cord. Under osteogenic differentiation conditions, all MSC populations formed calcium deposits and expressed higher SPARC. Over time, the expression of MSI1 followed different patterns for the different MSC populations. It was not significantly different than the expression of RUNX2. In contrast, the expression of MSI1 and POSTN and RUNX2 were statistically different in most MSC populations. Conclusion: In the current study, a similar expression pattern of MSI1 and RUNX2 during in vitro osteogenic differentiation was identified.
Rice Bran Ash Mineral Extract Increases Pigmentation through the p-ERK Pathway in Zebrafish (Danio rerio)
Authors: Kim Yu-Mi , Lee Eun-Cheol , Lim Han-Moi , Seo Young-Kwon
Published: May 2019

The purpose of the present study is to evaluate the effect of rice bran ash mineral extract (RBM) on pigmentation in zebrafish (Danio rerio). Melanin has the ability to block ultraviolet (UV) radiation and scavenge free oxygen radicals, thus protecting the skin from their harmful effects. Agents that increase melanin synthesis in melanocytes may reduce the risk of photodamage and skin cancer. The present study investigates the effect of RBM on pigmentation in zebrafish and the underlying mechanism. RBM was found to significantly increase the expression of microphthalmia-associated transcription factor (MITF), a key transcription factor involved in melanin production. RBM also suppressed the phosphorylation of extracellular signal-regulated kinase (ERK), which negatively regulates zebrafish pigmentation. Together, these results suggest that RBM promotes melanin biosynthesis in zebrafish.
Diversity and Ecosystem Services of Trichoptera
Authors: Morse John C. , Frandsen Paul B. , Graf Wolfram , Thomas Jessica A.
Published: May 2019

The holometabolous insect order Trichoptera (caddisflies) includes more known species than all of the other primarily aquatic orders of insects combined. They are distributed unevenly; with the greatest number and density occurring in the Oriental Biogeographic Region and the smallest in the East Palearctic. Ecosystem services provided by Trichoptera are also very diverse and include their essential roles in food webs, in biological monitoring of water quality, as food for fish and other predators (many of which are of human concern), and as engineers that stabilize gravel bed sediment. They are especially important in capturing and using a wide variety of nutrients in many forms, transforming them for use by other organisms in freshwaters and surrounding riparian areas. The general pattern of evolution for trichopteran families is becoming clearer as more genes from more taxa are sequenced and as morphological characters are becoming understood in greater detail. This increasingly credible phylogeny provides a foundation for interpreting and hypothesizing the functional traits of this diverse order of freshwater organisms and for understanding the richness of the ecological services corresponding with those traits. Our research also is gaining insight into the timing of evolutionary diversification in the order. Correlations for the use of angiosperm plant material as food and case construction material by the earliest ancestors of infraorder Plenitentoria—by at least 175 Ma—may provide insight into the timing of the origin of angiosperms.
Design of a Smart Bartender with Peristaltic Pumps
Authors: Rybin Vyacheslav , Karimov Timur , Sigaeva Maria , Solomevich Ekaterina , Kolev Georgii , Kopets Ekaterina
Published: May 2019

In this paper, the development of a smart scalable system for liquid supply based on high-precision peristaltic pumps is described. The architecture of software and hardware for the proposed system is considered. This liquid supply system can be used for mixed and layered cocktail preparation in public catering establishments, such as bars, as well as for home use. Due to the flexibility and scalability of the system, it is possible to apply it in various branches of human activity, where fine dosing of liquids is required, e.g., for beverage mixing, cooking, health and medical applications. By using open architecture and software, this system can be built in a smart home environment. The cross-platform control software and an embedded Bluetooth module allow using the developed setup in various use case scenarios. The result of the project is a DIY-kit, capable of mixing 6 to 32 different liquids in specified proportions and the programmable sequence.
Azaphilones from the Marine Sponge-Derived Fungus Penicillium sclerotiorum OUCMDZ-3839
Authors: Jia Qian , Du Yuqi , Wang Chen , Wang Yi , Zhu Tonghan , Zhu Weiming
Published: May 2019

Four new azaphilones, sclerotiorins A–D (1–4), as well as the dimeric sclerotiorin E (5) of which we first determined its absolute configuration, and 12 known analogues (5–16) were isolated from the fermentation broth of Penicillium sclerotiorum OUCMDZ-3839 associated with a marine sponge Paratetilla sp.. The new structures, including absolute configurations, were elucidated by spectroscopic analyses, optical rotation, ECD spectra, X-ray single-crystal diffraction, and chemical transformations. Compounds 11 and 14 displayed significant inhibitory activity against α-glycosidase, with IC50 values of 17.3 and 166.1 μM, respectively. In addition, compounds 5, 7, 10, 12–14, and 16 showed moderate bioactivity against H1N1 virus.
Collagen Extracted from Bigeye Tuna (Thunnus obesus) Skin by Isoelectric Precipitation: Physicochemical Properties, Proliferation, and Migration Activities
Authors: Lin Xinhui , Chen Yinyue , Jin Huoxi , Zhao Qiaoling , Liu Chenjuan , Li Renwei , Yu Fangmiao , Chen Yan , Huang Fangfang , Yang Zuisu , Ding Guofang , Tang Yunping
Published: May 2019

Collagen was extracted from bigeye tuna (Thunnus obesus) skins by salting-out (PSC-SO) and isoelectric precipitation (PSC-IP) methods. The yield of the PSC-IP product was approximately 17.17% (dry weight), which was greater than the yield obtained from PSC-SO (14.14% dry weight). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis indicated that collagen from bigeye tuna skin belongs to collagen type I. Inductively coupled plasma mass spectrometry results indicate that the heavy metal abundance in PSC-IP was lower than the maximum acceptable amounts according to Chinese regulatory standards. In addition, results from a methylthiazolyldiphenyl-tetrazolium bromide assay and an in vitro scratch assay demonstrated that PSC-IP could promote the proliferation and migration of NIH-3T3 fibroblasts. Overall, results suggest PSC-IP could be used to rapidly extract collagen from marine by-products instead of traditional salting-out methods. Collagen from bigeye tuna skin may also have strong potential for cosmetic and biomedical applications.
Physical Activity versus Psychological Stress: Effects on Salivary Cortisol and Working Memory Performance
Authors: Ponce Pamela , del Arco Alberto , Loprinzi Paul
Published: May 2019

Background and Objective: The present study was designed to investigate whether acute physical activity and psychological stress produce different effects on cortisol release and working memory performance. Materials and Methods: Male subjects (N = 12; 18–35 years) were recruited and scheduled to come four times to our lab (within-subject design). For each counterbalanced visit, they performed one of the following four protocols: control, moderate physical activity (MOD), vigorous physical activity (VIG), and acute stress. Heart rate was monitored during every protocol. MOD and VIG were performed for 15 min and were defined as 40–50% and 70–80%, respectively, of their maximum heart rate. Acute stress was imposed via the Trier Social Stress Test (TSST). Salivary samples were collected before and after every protocol to assess cortisol concentrations. Working memory (WM) performance was evaluated through the 2N-Back task right after ending the protocol (early WM) and after a delay of 35 min (late WM). Results: VIG and stress, but not MOD, increased salivary cortisol concentrations. However, the increases of cortisol produced by VIG and stress were not significantly different. Also, there were no significant differences in working memory performance (late and early) in any of the experimental protocols tested. Conclusions: These results show that exercise (VIG) and stress produce similar effects on cortisol release and do not support the hypothesis that working memory capacity is influenced by elevated cortisol levels, either from varying exercise intensities or psychological stress.
Concentrating of Sugar Syrup in Bioethanol Production Using Sweeping Gas Membrane Distillation
Authors: A. Shirazi Mohammad , Kargari Ali
Published: May 2019

Membrane distillation (MD) is a relatively new and underdeveloped separation process which can be classified as a green technology. However, in order to investigate its dark points, sensitivity analysis and optimization studies are critical. In this work, a number of MD experiments were performed for concentrating glucose syrup using a sweeping gas membrane distillation (SGMD) process as a critical step in bioethanol production. The experimental design method was the Taguchi orthogonal array (an L9 orthogonal one) methodology. The experimental results showed the effects of various operating variables, including temperature (45, 55, and 65 °C), flow rate (200, 400, and 600 ml/min) and glucose concentration (10, 30, and 50 g/l) of the feed stream, as well as sweeping gas flow rate (4, 10, and 16 standard cubic feet per hour (SCFH)) on the permeate flux. The main effects of the operating variables were reported. An ANOVA analysis showed that the most and the least influenced variables were feed temperature and feed flow rate, each one with 62.1% and 6.1% contributions, respectively. The glucose rejection was measured at 99% for all experiments. Results indicated that the SGMD process could be considered as a versatile and clean process in the sugar concentration step of the bioethanol production.
High-Temperature Reduction and Melting Mechanism of Sinter with Different MgO Content
Authors: Guo He , Shen Fengman , Zhang Huaiyu , Gao Qiangjian , Jiang Xin
Published: May 2019

Adding MgO to sinter is considered to be a popular counter measure to cope with the use of high Al2O3 ores. The purpose of this paper is to investigate the effect of the MgO content on the reduction melting behavior in order to clarify the main mechanism of melting and dripping under simulated blast furnace (BF) conditions. It was found that reduction behavior was inhibited with an increased MgO content; the reduction mechanism was further investigated by means of XRD, SEM, and kinetic analysis. The influence of MgO on the melting mechanism of high basicity sinter was also studied. The softening start temperature and softening temperature increased, and the softening zone increased as a whole with the increased MgO contents from 1.3 to 2.0 wt%. The melting temperature was similar, because the MgO remained in an unslagged state and existed in wustite as FeO-MgO solid solution. The dripping temperature was increased; the main reason for this was that high melting-point slags appeared, and that it was more difficult for carburization to occur with increased MgO content. The most appropriate MgO content in the sinter was 1.3 wt% according to principal component analysis (PCA).
Properties of Components with Incrementally Formed Gears
Authors: Wernicke Sebastian , Sieczkarek Peter , Gies Soeren , Tekkaya A. Erman
Published: May 2019

The process class of sheet-bulk metal forming (SBMF) involves several advantages for the manufacture of functional components. Its incremental variant (iSBMF) enables a very flexible dimensioning of components. To treat the unfavorable manufacturing time of the incremental approach, this investigation is focused on an alternative process route using rotating forming tools, which decrease the process time significantly. After an analysis of the mechanical properties as well as the micro- and macroscopic surface quality, a quasi-static benchmark test was performed. Normalized by the weight of the component, gears manufactured by iSBMF and BS600 steel presented the same load capacity as gears manufactured by blanking with subsequent hardening. Here, using innovative high strength steels with a significant strain hardening behavior like high manganese steels enables for weight-reduced gears.
DynaStI: A Dynamic Retention Time Database for Steroidomics
Authors: Codesido Santiago , Randazzo Giuseppe Marco , Lehmann Fabio , González-Ruiz Víctor , García Arnaud , Xenarios Ioannis , Liechti Robin , Bridge Alan , Boccard Julien , Rudaz Serge
Published: May 2019

Steroidomics studies face the challenge of separating analytical compounds with very similar structures (i.e., isomers). Liquid chromatography (LC) is commonly used to this end, but the shared core structure of this family of compounds compromises effective separations among the numerous chemical analytes with comparable physico-chemical properties. Careful tuning of the mobile phase gradient and an appropriate choice of the stationary phase can be used to overcome this problem, in turn modifying the retention times in different ways for each compound. In the usual workflow, this approach is suboptimal for the annotation of features based on retention times since it requires characterizing a library of known compounds for every fine-tuned configuration. We introduce a software solution, DynaStI, that is capable of annotating liquid chromatography-mass spectrometry (LC–MS) features by dynamically generating the retention times from a database containing intrinsic properties of a library of metabolites. DynaStI uses the well-established linear solvent strength (LSS) model for reversed-phase LC. Given a list of LC–MS features and some characteristics of the LC setup, this software computes the corresponding retention times for the internal database and then annotates the features using the exact masses with predicted retention times at the working conditions. DynaStI is able to automatically calibrate its predictions to compensate for deviations in the input parameters. The database also includes identification and structural information for each annotation, such as IUPAC name, CAS number, SMILES string, metabolic pathways, and links to external metabolomic or lipidomic databases.
On the Impact of the Fabrication Method on the Performance of 3D Printed Mixers
Authors: Zeraatkar Mojtaba , Filippini Daniel , Percoco Gianluca
Published: May 2019

A wide variety of 3D printing technologies have been used for the fabrication of lab-on-a-chip (LOC) devices in recent years. Despite the large number of studies having examined the use of 3D printing technologies in microfluidic devices, the effect of the fabrication method on their performance has received little attention. In this paper, a comparison is shown between unibody-LOC micro-mixers, a particular type of monolithic design for 3D printed LOCs, fabricated in polyjet, stereolithography (SLA) and fused deposition modelling (FDM or FFF) platforms, paying particular attention to the inherent limitations of each fabrication platform and how these affect the performance of the manufactured devices.
Recovery of Alkali from Bayer Red Mud Using CaO and/or MgO
Authors: Zhou Bingxin , Cao Shaotao , Chen Fangfang , Zhang Fangfang , Zhang Yi
Published: May 2019

Recovering alkali from Bayer red mud is crucial for storage security, resource utilization and environmental protection. In this study, the addition of MgO and/or CaO was conducted to recover alkali from red mud with a hydrothermal method for the first time. A synergistic result with a residual Na2O/SiO2 weight ratio of 0.03 was obtained by adding the blend of CaO and MgO at an appropriate temperature. MgO was found to be more temperature-dependent than CaO when substituting Na2O from red mud due to their different hydration processes. The alkali recovery was controlled by a reaction at a temperature of <200 °C and by internal diffusion at a higher temperature for MgO, but controlled by internal diffusion for CaO in the whole temperature range studied. The formation of hydrotalcite-like compounds with a loose structure was verified with the help of XRD, FTIR, and SEM-EDS. It was proved that both the reaction kinetics and the characteristics of solid products have a significant influence on the recovery of alkali.
Phenolic Profile and Bioactive Properties of Carissa macrocarpa (Eckl.) A.DC.: An In Vitro Comparative Study between Leaves, Stems, and Flowers
Authors: Souilem Fedia , Dias Maria Inês , Barros Lillian , Calhelha Ricardo C. , Alves Maria José , Harzallah-Skhiri Fethia , Ferreira Isabel C.F.R.
Published: May 2019

The present work aimed to characterize leaves, stems, and flowers of Carissa macrocarpa (Eckl.) A.DC., by performing an analysis of the phenolic compounds by HPLC-DAD/ESI-MS, correlating them with bioactive properties, such as antioxidant, anti-inflammatory, cytotoxic, and antimicrobial activities. Thirty polyphenols were identified in the hydroethanolic extract, including phenolic acids, flavan-3-ols, and flavonol glycosides derivatives (which presented the highest number of identified compounds). However, flavan-3-ols showed the highest concentration in stems (mainly owing to the presence of dimers, trimmers, and tetramers of type B (epi)catechin). Leaves were distinguished by their high antioxidant and anti-inflammatory activities, as well as their bactericidal effect against E. coli, while stems presented a higher cytotoxic activity and bactericidal effect against Gram-positive bacteria. Moreover, a high correlation between the studied bioactivities and the presence of phenolic compounds was also verified. The obtained results bring added value to the studied plant species.
The Preparation, Determination of a Flexible Complex Liposome Co-Loaded with Cabazitaxel and β-Elemene, and Animal Pharmacodynamics on Paclitaxel-Resistant Lung Adenocarcinoma
Authors: Zeng Yi-Ying , Zeng Yi-Jun , Zhang Na-Na , Li Chen-Xi , Xie Tian , Zeng Zhao-Wu
Published: May 2019

Paclitaxel is highly effective at killing many malignant tumors; however, the development of drug resistance is common in clinical applications. The issue of overcoming paclitaxel resistance is a difficult challenge at present. In this study, we developed nano drugs to treat paclitaxel-resistant lung adenocarcinoma. We selected cabazitaxel and β-elemene, which have fewer issues with drug resistance, and successfully prepared cabazitaxel liposome, β-elemene liposome and cabazitaxel-β-elemene complex liposome with good flexibility. The encapsulation efficiencies of cabazitaxel and β-elemene in these liposomes were detected by precipitation microfiltration and microfiltration centrifugation methods, respectively. Their encapsulation efficiencies were all above 95%. The release rates were detected by a dialysis method. The release profiles of cabazitaxel and β-elemene in these liposomes conformed to the Weibull equation. The release of cabazitaxel and β-elemene in the complex liposome were almost synchronous. The pharmacodynamics study showed that cabazitaxel flexible liposome and β-elemene flexible liposome were relatively good at overcoming paclitaxel resistance on paclitaxel-resistant lung adenocarcinoma. As the flexible complex liposome, the dosage of cabazitaxel could be reduced to 25% that of the cabazitaxel injection while retaining a similar therapeutic effect. It showed that β-elemene can replace some of the cabazitaxel, allowing the dosage of cabazitaxel to be reduced, thereby reducing the drug toxicity.
Kinetics and Thermodynamics of Mg-Al Disorder in MgAl2O4-Spinel: A Review
Authors: Ma Yunlu , Liu Xi
Published: May 2019

The MgAl2O4-spinel has wide applications in various industries and in geosciences. It shows a significant inter-site Mg-Al cation exchange (denoted by the inversion parameter x), which modifies structural features, such as the unit-cell parameters and the sizes of the component polyhedra, and influences the physical and chemical properties. Previous studies mainly focused on the kinetics and thermodynamics of the Mg-Al exchange reaction, with the aim to ascertain the correlation between the inversion parameter and temperature; these studies, however, reached conflicting results. Here, we first reviewed the kinetics studies on the Mg-Al cation exchange reaction, and then reviewed all thermodynamic experiments, with special attention paid to the Mg-Al cation exchange equilibrium and the quench process, which might have modified the cation distributions once attained at high temperatures. We also assessed the accuracies in the temperature measurements and in the quantifications of the x by different analytical methods. With some necessary temperature correction and data removal, we have landed with a generally reliable x-T dataset covering the T-x space of 873 < T < 1887 K and 0.18(1) < x < 0.357(60) (71 data pairs in total). Fitting these x-T data to three most commonly used thermodynamic models, we have obtained more accurate model parameters. Further, we also evaluated the constituent items of the Gibbs free energy for the Mg-Al cation exchange reaction with experimental results from different research fields and reached the conclusion that highly possibly the T Δ S D should not be neglected. Based on this review, we suggest that: (1) Further kinetics study on the Mg-Al exchange reaction should be performed at both low T (<~973 K) and high T (>~1173 K); (2) further Mg-Al exchange equilibrium studies should be carried out at relatively low T and ambient P, as well as in vast ranges of simultaneous high P and high T; and (3) direct experimental measures about the entropies or the enthalpies of the MgAl2O4-spinels disordered to different extents should be conducted with full characterization of the starting materials and detailed description of the experimental procedures.
Preparation of a Novel SERS Platform Based on Mantis Wing with High-Density and Multi-Level “Hot Spots”
Authors: Wang Mingli , Shi Guochao , Zhu Junlin , Zhu Yanying , Sun Xin , Wang Peng , Jiao Tifeng , Li Ruifeng
Published: May 2019

The recent development of SERS substrates based on irregular nanostructures for directly molecule recognition has aroused increasing attention. By combining the irregular flake-like nanostructures of mantis wings, high SERS performance of Ag nanofilms, and the chemical stability of Au nanoparticles (NPs), an ultra-sensitive and flexible SERS substrate based on Au NPs functionalized Ag nanofilms-mantis wings (Au-Ag-M.w.) hybrid system is successfully fabricated. When 4-aminothiophenol is selected as the probe molecule, the limit of detection (LOD) is as low as 10−13 M and the relative standard deviation (RSD) is lower than 7.15%. This novel SERS platform exhibits high SERS performance in terms of sensitivity, reproducibility and practicability mainly because there are high-density and multi-level “hot spots” in the appropriate nanogaps. Meanwhile, it also systematically compares the differences of the SERS performance of Cu and Ag decorated M.w. hybrids and how these differences can alter their response. Moreover, the proposed substrate is employed to rapidly detect the pesticide residues on apple peels and the LOD for cypermethrin is estimated at 10−10 mg/mL. Therefore, this novel SERS substrate has great potential in rapid sampling of pesticide residues on real samples and expands the investigation to other natural materials for fabricating various SERS platforms.
Linearly Tunable Fano Resonance Modes in a Plasmonic Nanostructure with a Waveguide Loaded with Two Rectangular Cavities Coupled by a Circular Cavity
Authors: Wang Qiong , Ouyang Zhengbiao , Sun Yiling , Lin Mi , Liu Qiang
Published: May 2019

Linear tunability has important applications since it can be realized by using linear control voltage and can be used conveniently without requiring nonlinear scale. In this paper, a kind of plasmonic nanostructure with a waveguide loaded with two rectangular cavities coupled by a circular cavity is proposed to produce four Fano resonance modes. The transfer matrix theory is employed to analyze the coupled-waveguide-cavity system. By analyzing the property of each single cavity, it reveals that the Fano resonances are originated from the coupling effect of the narrow modes in the metal-core circular cavity and the broad modes in the rectangular cavities. Owing to the interference of different modes, Fano peaks have different sensitivities on the cavity parameters, which can provide important guidance for designing Fano-resonance structures. Furthermore, adjusting the orientation angle of the metal core in the circular cavity can easily tune the line profile of Fano resonance modes in the structure. Especially, the figure of merit (FoM) increases linearly with the orientation angle and has a maximum of 8056. The proposed plasmonic system has the advantage of high transmission, ultracompact configuration, and easy integration, which can be applied in biochemical detecting or sensing, ultra-fast switching, slow-light technologies, and so on.
Development of a Ternary Solid Dispersion Formulation of LW6 to Improve the In Vivo Activity as a BCRP Inhibitor: Preparation and In Vitro/In Vivo Characterization
Authors: Bajracharya Rajiv , Lee Sang Hoon , Song Jae Geun , Kim Minkyoung , Lee Kyeong , Han Hyo-Kyung
Published: May 2019

LW6 (3-[2-(4-adamantan-1-yl-phenoxy)-acetylamino]-4-hydroxy-benzoic acid methyl ester) is a potent inhibitor of drug efflux by the breast cancer resistance protein (BCRP). However, its poor aqueous solubility leads to low bioavailability, which currently limits in vivo applications. Therefore, the present study aimed to develop ternary solid dispersion (SD) formulations in order to enhance the aqueous solubility and dissolution rate of LW6. Various SDs of LW6 were prepared using a solvent evaporation method with different drug/excipient ratios. The solubility and dissolution profiles of LW6 in different SDs were examined, and F8-SD which is composed of LW6, poloxamer 407, and povidone K30 at a weight ratio of 1:5:8 was selected as the optimal SD. The structural characteristics of F8-SD were also examined using Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), X-ray powder diffraction (XRPD), and scanning electron microscopy (SEM). In the acidic to neutral pH range, F8-SD achieved rapid dissolution with a drug release of 76–81% within 20 min, while the dissolution of pure LW6 was negligible. The XRPD patterns indicated that F8-SD probably enhanced the solubility and dissolution of LW6 by changing the drug crystallinity to an amorphous state, in addition to the solubilizing effect of the hydrophilic carriers. Furthermore, F8-SD significantly improved the oral bioavailability of topotecan, which is a BCRP substrate, in rats. The systemic exposure of topotecan was enhanced approximately 10-fold by the concurrent use of F8-SD. In conclusion, the ternary SD formulation of LW6 with povidone K30 and poloxamer 407 appeared to be effective at improving the dissolution and in vivo effects of LW6 as a BCRP inhibitor.
High-Throughput Genotype, Morphology, and Quality Traits Evaluation for the Assessment of Genetic Diversity of Wheat Landraces from Sicily
Authors: Fiore Maria Carola , Mercati Francesco , Spina Alfio , Blangiforti Sebastiano , Venora Gianfranco , Dell’Acqua Matteo , Lupini Antonio , Preiti Giovanni , Monti Michele , Pè Mario Enrico , Sunseri Francesco
Published: May 2019

During the XX Century, the widespread use of modern wheat cultivars drastically reduced the cultivation of ancient landraces, which nowadays are confined to niche cultivation areas. Several durum wheat landraces adapted to the extreme environments of the Mediterranean region, are still being cultivated in Sicily, Italy. Detailed knowledge of the genetic diversity of this germplasm could lay the basis for their efficient management in breeding programs, for a wide-range range of traits. The aim of the present study was to characterize a collection of durum wheat landraces from Sicily, using single nucleotide polymorphisms (SNP) markers, together with agro-morphological, phenological and quality-related traits. Two modern cv. Simeto, Claudio, and the hexaploid landrace, Cuccitta, were used as outgroups. Cluster analysis and Principal Coordinates Analysis (PCoA) allowed us to identify four main clusters across the analyzed germplasm, among which a cluster included only historical and modern varieties. Likewise, structure analysis was able to distinguish the ancient varieties from the others, grouping the entries in seven cryptic genetic clusters. Furthermore, a Principal Component Analysis (PCA) was able to separate the modern testers from the ancient germplasm. This approach was useful to classify and evaluate Sicilian ancient wheat germplasm, supporting their safeguard and providing a genetic fingerprint that is necessary for avoiding commercial frauds to sustaining the economic profits of farmers resorting to landraces cultivation.
Rheological Study on the Thermoreversible Gelation of Stereo-Controlled Poly(N-Isopropylacrylamide) in an Imidazolium Ionic Liquid
Authors: Yan Zhi-Chao , Biswas Chandra Sekhar , Stadler Florian J.
Published: May 2019

The thermoreversible sol-gel transition for an ionic liquid (IL) solution of isotactic-rich poly (N-isopropylacrylamides) (PNIPAMs) is investigated by rheological technique. The meso-diad content of PNIPAMs ranges between 47% and 79%, and molecular weight (Mn) is ~35,000 and ~70,000 g/mol for two series of samples. PNIPAMs are soluble in 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl) imide ([BMIM][TFSI]) at high temperatures but undergo a gelation with decreasing temperatures. The transition temperature determined from G’-G” crossover increases with isotacticity, consistent with the previous cloud-point result at the same scanning rate, indicating imide groups along the same side of backbones are prone to be aggregated for formation of a gel. The transition point based on Winter-Chambon criterion is on average higher than that of the G’-G” crossover method and is insensitive to tacticity and molecular weight, since it correlates with percolation of globules rather than the further formation of elastic network (G’ > G”). For the first time, the phase diagram composed of both G’-G” crossover points for gelation and cloud points is established in PNIPAM/IL mixtures. For low-Mn PNIPAMs, the crossover-point line intersects the cloud-point line. Hence, from solution to opaque gel, the sample will experience two different transitional phases, either clear gel or opaque sol. A clear gel is formed due to partial phase separation of isotactic segments that could act as junctions of network. However, when the partial phase separation is not faster than the formation of globules, an opaque sol will be formed. For high-Mn PNIPAMs, crossover points are below cloud points at all concentrations, so their gelation only follows the opaque sol route. Such phase diagram is attributed to the poorer solubility of high-Mn polymers for entropic reasons. The phase diagram composed of Winter-Chambon melting points, crossover points for melting, and clear points is similar with the gelation phase diagram, confirming the mechanism above.