bluuebunny/crossref_metadata_2025 huggingface dataset:
FACTORS ASSOCIATED WITH SCHOOL REFUSAL BEHAVIOUR IN PRIMARY SCHOOL STUDENTS
Authors: Balakrishnan Rukmani Devi , Andi Hari Krishnan
Published: January 2019

The aim of this study was to identify the factors associated with school refusal behavior in primary school students. Student’s self-report and teacher’s measures were implemented; and students were recruited from 20 primary schools in six districts in Selangor, Malaysia. The survey was conducted at the end of school term in 2016, with a total of 915 students from Year 4 and Year 5 participating. The sample of students had been absent from school for more than 15% of school days in the current year. Pearson correlation shows a significant relationship between academic achievement and school satisfaction toward school refusal behavior. The findings of this study suggest that academic difficulties and dissatisfaction towards school environment could be the important risk factors for school refusal behavior. The present study underscores the importance of early detection and intervention as measures to reduce school refusal. Finally, the findings imply that the role of school factors should always be taken into account in connection with school refusal behaviour.
Ignition and combustion of titanium particles: experimental methods and results
Authors: Glotov O G
Published: January 2019

We have collected and systematized data on patterns and features of the ignition and combustion of titanium in the form of centimeter-sized samples and microparticles with dimensions ranging from several units to several hundred micrometers in the shape of individual particles, air suspensions, and poured and pressed samples. Factors have been identified that affect the temperature and time characteristics of ignition and burning, as well as the composition and dispersity of the formed condensed products, including those in the nanometer-sized range. We also present a modern paradigm of the mechanism of burning and formulate the issues to be resolved to gain a better understanding of how metal transforms into oxide.
Binding of Immunoglobulin G to Protoporphyrin IX and Its Derivatives: Evidence the Fab Domain Recognizes the Protoporphyrin Ring
Authors: Orino Koichi
Published: January 2019

Immunoglobulin G (IgG) is known to bind zinc via the Fc domain. In this study, biotinylated protoporphyrin IX (PPIX) was incubated with human IgG and then zinc-immobilized Sepharose beads (Zn-beads) were added to the mixture. After washing the beads, the binding of biotinylated PPIX with IgG trapped on Zn-beads was detected using alkaline phosphatase (ALP)-labeled avidin. Human IgG and its Fab domain coated on microtiter plate wells recognized biotin-labeled PPIX and its derivatives, Fe-PPIX and Zn-PPIX, whereas the Fc domain showed some extent of reaction only with Zn-PPIX. When rabbit anti-bovine transferrin (Tf) antibodies were incubated with biotinylated PPIX, the binding of anti-Tf antibodies with apo-Tf was indirectly detected using ALP-labeled avidin, suggesting that even if the antibody is modified with PPIX, the antibody-antigen reaction occurs. These results suggest that the IgG Fab domain recognizes PPIX and its derivatives, probably via the recognition of the PPIX ring. It is unlikely that binding between the Fab domain and PPIX affects the Fc domain-zinc interaction or antigen-antibody reaction.
Effective and Novel Application of Hydrodynamic Voltammetry to the Study of Superoxide Radical Scavenging by Natural Phenolic Antioxidants
Authors: Belli Stuart , Rossi Miriam , Molasky Nora , Middleton Lauren , Caldwell Charles , Bartow-McKenney Casey , Duong Michelle , Chiu Jana , Gibbs Elizabeth , Caldwell Allison , Gahn Christopher , Caruso Francesco
Published: January 2019

The reactions of antioxidants with superoxide radical were studied by cyclic voltammetry (CV)—and hydrodynamic voltammetry at a rotating ring-disk electrode (RRDE). In both methods, the superoxide is generated in solution from dissolved oxygen and then measured after being allowed to react with the antioxidant being studied. Both methods detected and measured the radical scavenging but the RRDE was able to give detailed insight into the antioxidant behavior. Three flavonoids, chrysin, quercetin and eriodictyol, were studied, their scavenging activity of superoxide was assessed and the molecular structure of each flavonoid was related to its scavenging capability. From our improved and novel RRDE method, we determine the ability of these 3 antioxidants to react with superoxide radical in a more quantitative manner than the classical CV. Density Functional Theory (DFT) and single crystal X-ray diffraction data provide structural information that assists in clarifying the scavenging molecular mechanism. Hydroxyls associated with the A ring, as found in chrysin, scavenge superoxide in a different manner than those found in the B ring of flavonoids, as those in quercetin and eriodictyol.
Filling Gaps in Hourly Air Temperature Data Using Debiased ERA5 Data
Authors: Lompar Miloš , Lalić Branislava , Dekić Ljiljana , Petrić Mina
Published: January 2019

Missing data in hourly and daily temperature data series is a common problem in long-term data series and many observational networks. Agricultural and environmental models and climate-related tools can be used only if weather data series are complete. To support user communities, a technique for gap filling is developed based on the debiasing of ERA5 reanalysis data, the fifth generation of the European Centre for Medium-Range Weather Forecasts (ECMWF) atmospheric reanalyses of the global climate. The debiasing procedure includes in situ measured temperature. The methodology is tested for different landscapes, latitudes, and altitudes, including tropical and midlatitudes. An evaluation of results in terms of root mean square error (RMSE) obtained using hourly and daily data is provided. The study shows very low average RMSE for all gap lengths ranging from 1.1 °C (Montecristo, Italy) to 1.9 °C (Gumpenstein, Austria).
Transient Disappearance of RAS Mutant Clones in Plasma: A Counterintuitive Clinical Use of EGFR Inhibitors in RAS Mutant Metastatic Colorectal Cancer
Authors: Raimondi Cristina , Nicolazzo Chiara , Belardinilli Francesca , Loreni Flavia , Gradilone Angela , Mahdavian Yasaman , Gelibter Alain , Giannini Giuseppe , Cortesi Enrico , Gazzaniga Paola
Published: January 2019

Genomic studies performed through liquid biopsies widely elucidated the evolutionary trajectory of RAS mutant clones under the selective pressure of EGFR inhibitors in patients with wild type RAS primary colorectal tumors. Similarly, the disappearance of RAS mutant clones in plasma has been more recently reported in some patients with primary RAS mutant cancers, supporting for the first time an unexpected negative selection of RAS mutations during the clonal evolution of mCRC. To date, the extent of conversion to RAS wild type disease at the time of progression has not been clarified yet. As a proof of concept, we prospectively enrolled mCRC patients progressing under anti-VEGF based treatments. Idylla™ system was used to screen RAS mutations in plasma and the wild type status of RAS was further confirmed through IT-PGM (Ion Torrent Personal Genome Machine) sequencing. RAS was found mutant in 55% of cases, retaining the same plasma mutation as in the primary tumor at diagnosis, while it was found wild-type in 45%. Four patients testing negative for RAS mutations in plasma at the time of progression of disease (PD) were considered eligible for treatment with EGFR inhibitors and treated accordingly, achieving a clinical benefit. We here propose a hypothetical algorithm that accounts for the transient disappearance of RAS mutant clones over time, which might extend the continuum of care of mutant RAS colorectal cancer patients through the delivery of a further line of therapy.
Poly-ADP-Ribosylation of Estrogen Receptor-Alpha by PARP1 Mediates Antiestrogen Resistance in Human Breast Cancer Cells
Authors: Pulliam Nicholas , Tang Jessica , Wang Weini , Fang Fang , Sood Riddhi , O’Hagan Heather M. , Miller Kathy D. , Clarke Robert , Nephew Kenneth P.
Published: January 2019

Therapeutic targeting of estrogen receptor-α (ERα) by the anti-estrogen tamoxifen is standard of care for premenopausal breast cancer patients and remains a key component of treatment strategies for postmenopausal patients. While tamoxifen significantly increases overall survival, tamoxifen resistance remains a major limitation despite continued expression of ERα in resistant tumors. Previous reports have described increased oxidative stress in tamoxifen resistant versus sensitive breast cancer and a role for PARP1 in mediating oxidative damage repair. We hypothesized that PARP1 activity mediated tamoxifen resistance in ERα-positive breast cancer and that combining the antiestrogen tamoxifen with a PARP1 inhibitor (PARPi) would sensitize tamoxifen resistant cells to tamoxifen therapy. In tamoxifen-resistant vs. -sensitive breast cancer cells, oxidative stress and PARP1 overexpression were increased. Furthermore, differential PARylation of ERα was observed in tamoxifen-resistant versus -sensitive cells, and ERα PARylation was increased by tamoxifen treatment. Loss of ERα PARylation following treatment with a PARP inhibitor (talazoparib) augmented tamoxifen sensitivity and decreased localization of both ERα and PARP1 to ERα-target genes. Co-administration of talazoparib plus tamoxifen increased DNA damage accumulation and decreased cell survival in a dose-dependent manner. The ability of PARPi to overcome tamoxifen resistance was dependent on ERα, as lack of ERα-mediated estrogen signaling expression and showed no response to tamoxifen-PARPi treatment. These results correlate ERα PARylation with tamoxifen resistance and indicate a novel mechanism-based approach to overcome tamoxifen resistance in ER+ breast cancer.
Personalized Prediction of Acquired Resistance to EGFR-Targeted Inhibitors Using a Pathway-Based Machine Learning Approach
Authors: Kim Young , Kim Yong , Lee Suh , Yang Hye , Kim Sung
Published: January 2019

Epidermal growth factor receptor (EGFR) inhibitors have benefitted cancer patients worldwide, but resistance inevitably develops over time, resulting in treatment failures. An accurate prediction model for acquired resistance (AR) to EGFR inhibitors is critical for early diagnosis and according intervention, but is not yet available due to personal variations and the complex mechanisms of AR. Here, we have developed a novel pipeline to build a meta-analysis-based, multivariate model for personalized pathways in AR to EGFR inhibitors, using sophisticated machine learning algorithms. Surprisingly, the model achieved excellent predictive performance, with a cross-study validation area under curve (AUC) of over 0.9, and generalization performance on independent cohorts of samples, with a perfect AUC score of 1. Furthermore, the model showed excellent transferability across different cancer cell lines and EGFR inhibitors, including gefitinib, erlotinib, afatinib, and cetuximab. In conclusion, our model achieved high predictive accuracy through robust cross study validation, and enabled individualized prediction on newly introduced data. We also discovered common pathway alteration signatures for AR to EGFR inhibitors, which can provide directions for other follow-up studies.
Thin Films Sensor Devices for Mycotoxins Detection in Foods: Applications and Challenges
Authors: Santos Andréia , Vaz Andreia , Rodrigues Paula , Veloso Ana , Venâncio Armando , Peres António
Published: January 2019

Mycotoxins are a group of secondary metabolites produced by different species of filamentous fungi and pose serious threats to food safety due to their serious human and animal health impacts such as carcinogenic, teratogenic and hepatotoxic effects. Conventional methods for the detection of mycotoxins include gas chromatography and high-performance liquid chromatography coupled with mass spectrometry or other detectors (fluorescence or UV detection), thin layer chromatography and enzyme-linked immunosorbent assay. These techniques are generally straightforward and yield reliable results; however, they are time-consuming, require extensive preparation steps, use large-scale instruments, and consume large amounts of hazardous chemical reagents. Rapid detection of mycotoxins is becoming an increasingly important challenge for the food industry in order to effectively enforce regulations and ensure the safety of food and feed. In this sense, several studies have been done with the aim of developing strategies to detect mycotoxins using sensing devices that have high sensitivity and specificity, fast analysis, low cost and portability. The latter include the use of microarray chips, multiplex lateral flow, Surface Plasmon Resonance, Surface Enhanced Raman Scattering and biosensors using nanoparticles. In this perspective, thin film sensors have recently emerged as a good candidate technique to meet such requirements. This review summarizes the application and challenges of thin film sensor devices for detection of mycotoxins in food matrices.
Detection and Control of Invasive Freshwater Crayfish: From Traditional to Innovative Methods
Authors: Manfrin Chiara , Souty-Grosset Catherine , Anastácio Pedro M. , Reynolds Julian , Giulianini Piero G.
Published: January 2019

Invasive alien species are widespread in freshwater systems compared to terrestrial ecosystems. Among crustaceans, crayfish in particular have been widely introduced and are considered a major threat to freshwater ecosystem functioning. New emerging techniques for detecting and controlling invasive crayfish and protecting endangered native species are; thus, now highly desirable and several are under evaluation. Important innovations have been developed in recent years for detection of both invasive and native crayfish, mainly through eDNA, which allows for the detection of the target species even at low abundance levels and when not directly observable. Forecasting models have also moved towards the creation of realistic invasion scenarios, allowing effective management plans to be developed in advance of invasions. The importance of monitoring the spread and impacts of crayfish and pathogens in developing national data and research networks is emphasised; here “citizen science” can also play a role. Emerging techniques are still being considered in the field of invasive crayfish control. Although for decades the main traditional techniques to manage invasive crayfish were solely based on trapping, since 2010 biological, biocidal, autocidal controls and sexual attractants, monosex populations, RNA interference, the sterile male release technique and oral delivery have all also been investigated for crayfish control. In this review, ongoing methodologies applied to the detection and management of invasive crayfish are discussed, highlighting their benefits and limitations.
Economic Performance of Using Batteries in European Residential Microgrids under the Net-Metering Scheme
Authors: Saviuc Iolanda , Peremans Herbert , Van Passel Steven , Milis Kevin
Published: January 2019

Decentralized energy production offers an increased share of renewable energy and autonomy compared to the conventional, grid-only solution. However, under the net-metering scheme, the energy losses in batteries translate into financial losses to an investor seeking to move away from grid-only electricity and set up a residential PV+Battery microgrid. Our paper examines a hypothetical support scheme for such a project, designed to balance the economic disadvantage through partially supporting the acquisition of batteries, and thus ensure that the microgrid solution is more attractive than no investment. For this we develop four case studies based on experiments carried out in Greece, Italy, Denmark and Finland. Using the minimization of the Net Present Cost for each project, we compare the PV+Battery solution to the grid-only scenario over 25 years, for a range of electricity prices. The results illustrate first how the success of this project depends on the price of electricity. Second, we find that under current conditions in the respective countries the need for battery support varies between zero in Denmark and 86% in Italy, which reflects how the disadvantages of net metering can only be counterbalanced by either very high electricity price or very high solar resource. Our paper contributes thus to the discussion about the favourable environment for batteries in residential microgrids.
Photovoltaic Integrated Hybrid Microgrid Structured Electric Vehicle Charging Station and Its Energy Management Approach
Authors: Savio Dominic A. , Juliet Vimala A. , Chokkalingam Bharatiraja , Padmanaban Sanjeevikumar , Holm-Nielsen Jens Bo , Blaabjerg Frede
Published: January 2019

A hybrid microgrid-powered charging station reduces transmission losses with better power flow control in the modern power system. However, the uncoordinated charging of battery electric vehicles (BEVs) with the hybrid microgrid results in ineffective utilization of the renewable energy sources connected to the charging station. Furthermore, planned development of upcoming charging stations includes a multiport charging facility, which will cause overloading of the utility grid. The paper analyzes the following technical issues: (1) the energy management strategy and converter control of multiport BEV charging from a photovoltaic (PV) source and its effective utilization; (2) maintenance of the DC bus voltage irrespective of the utility grid overloading, which is caused by either local load or the meagerness of PV power through its energy storage unit (ESU). In addition, the charge controller provides closed loop charging through constant current and voltage, and this reduces the charging time. The aim of an energy management strategy is to minimize the usage of utility grid power and store PV power when the vehicle is not connected for charging. The proposed energy management strategy (EMS) was modeled and simulated using MATLAB/Simulink, and its different modes of operation were verified. A laboratory-scale experimental prototype was also developed, and the performance of the proposed charging station was investigated.
Extraction of Temperature-Dependent Thermoelectric Material Parameters of a Thermoelectric Cooler by the Non-Linear Least Squares Method
Authors: Nie Shanjun , Wang Mingfu , Gao Xiaodong , Liao Jingyu
Published: January 2019

This paper presents a method of extracting temperature-dependent parameters of thermoelectric material from the operating conditions of thermoelectric cooler (TEC). Based on the finite element method of calculating TEC’s performance, non-linear least squares method is used for extracting temperature-dependent material parameters including the seebeck coefficient, electrical resistivity and thermal conductivity (α, ρ, κ) as operating current, thermal load and hot end temperature are taken as inputs and cooling temperature is taken as output. To further improve the voltage calculation accuracy, the electric resistance error factor which includes electrical contact resistance and the calculation model error is extracted with the voltage being output on the basis of extracted material parameters. The cooling temperature and voltage of another TEC with the same thermoelectric material are recalculated by the extracted parameters and the exact parameters provided by manufacturer respectively. Compared with the experimental results, the extracted material parameters have the advantages of high accuracy, wide application ranges and easily implementing in evaluating TECs’ performance.
Assessing Health Effects and Soundscape Analysis as New Mitigation Actions Concerning the Aircraft Noise Impact in Small- and Middle-Size Urban Areas in Greece
Authors: Gerolymatou Georgia , Rémy Nicolas , Vogiatzis Konstantinos , Zafiropoulou Vassiliki
Published: January 2019

In 2013 and 2014, two main International Airports in Greece were evaluated through the European directive on noise environment 2002/49/EC: “Nikos Kazantzakis” International Airport of Heraklion Crete and “Ioannis—Kapodistrias” International Airport in Corfu, both located in highly touristic areas of Greece. Acoustic measurement’s campaign, environmental noise mapping simulations and population exposure to noise were implemented in order to produce a complete Strategic Noise Map. Correlated to this acoustic approach, a comprehensive interview campaign and a detailed soundscape analysis were also conducted in both airports’ adjacent areas (Alikarnassos district in Heraklion and the peninsula of Canoni in Corfu City) in order to understand the impact of aircraft movements on both local residents and tourists, and analyze the perception of the soundscapes. A similar evaluation was also executed in order to assess possible health effects by using the WHO’s DALY’s (Disability Adjusted Life Year) metrics for environmental noise in relation to the exposure of the population. This paper presents the main results of these representative case studies, attempting a combined assessment of both health effects and soundscape characteristics to be used as evaluation tools towards the management and the rehabilitation acoustic environment characterized mainly by aircraft noise in touristic areas.
The Spatial Distribution of the Needle Area of Planted Larix olgensis Trees
Authors: Liu Qiang , Xie Longfei , Li Fengri
Published: January 2019

The spatial distribution of leaf area largely governs both the structure and function of a tree crown. Three sample trees were selected from a 16-year-old Larix olgensis plantation in the Maoershan Forest Farm, Heilongjiang Province, based on the average diameter at breast height in each plot. All needles from the branches in the nodal and internodal pseudowhorls within the crown were destructively sampled. The crown was divided into several segments in the vertical and horizontal directions, resulting in different sub-regions. The needle area (NA) in each sub-region was computed based on the needle mass per area (NMA). The vertical and horizontal distributions and their cumulative NA distributions were characterized using the Weibull distribution function and its cumulative form. A two-dimensional NA model was created by combining the two Weibull distribution functions of the vertical and horizontal distributions. The variation in the spatial distribution of the NA among the different crown directions is discussed, and the influence of competition from competitors on the spatial distribution of NA was analyzed. The results showed that the Weibull distribution function and its cumulative form performed well in describing the vertical and horizontal distributions and the cumulative distributions of the NA, which was generally concentrated upward within the crown. This phenomenon was most apparent in dense stands with strong competition. The center of the NA exhibited an inward shift in the horizontal direction within the crown but shifted outwards with an increase in competition. The cumulative vertical and horizontal distributions of the NA obviously varied with different crown directions, which was associated mainly with the light conditions. The two-dimensional NA patterns showed that the center of the NA generally shifted outward with an increase in the relative depth into the crown (RDINC), and that more concentrated and more skewed patterns usually occurred under increased competition. Different crown directions exhibited different two-dimensional NA patterns, but the core driver was the variable light condition caused by the competitors, particularly in closed stands.
Application of a Non-Immersive VR, IoT Based Approach to Help Moroccan Students Carry Out Practical Activities in a Personal Learning Style
Authors: Fahim Mohamed , Ouchao Brahim , Jakimi Abdeslam , El Bermi Lahcen
Published: January 2019

In the last few years, the evolution of new Information and Communication Technologies (ICT) and networks has enabled the appearance and development of several platforms and tools that serve to operate and distribute the learning content. In some particular domains, especially the scientific one, learners need to work on practical activities, using specific products and equipment to complete, consolidate, or verify their conceptual acquisitions. However, facing the increasing number of learners in Moroccan institutions, it becomes hard and expensive for developing countries, like Morocco, to ensure the appropriate conditions for each learner to perform such activities. The majority of the suggested platforms and tools cannot solve this issue, because of their inefficiency regarding offering students good interactive practical activities. Virtual Reality (VR) and the Internet of Things (IoT), as the two most incredible technologies of the last few decades, can be used as an alternative to create a virtual environment where the learner can carry out practical activities like in the real world. In such an environment, learners interact with both virtual and physical objects. In this research paper, we propose a new approach based on VR and IoT to enhance learning by providing learners with an educational space where they can perform some practical activities. The hybrid proposed approach has been used to create a virtual environment where learners (the final year of high school) can measure ultrasonic velocity in the air. The evaluation results show that the manipulation and coupling of real objects with virtual 3D objects increases in a striking way the learning outcomes of learners, as this allows them to feel linked to the real context.
Advancing Chemical Risk Assessment through Human Physiology-Based Biochemical Process Modeling
Authors: Sarigiannis Dimosthenis , Karakitsios Spyros
Published: January 2019

Physiology-Based BioKinetic (PBBK) models are of increasing interest in modern risk assessment, providing quantitative information regarding the absorption, metabolism, distribution, and excretion (ADME). They focus on the estimation of the effective dose at target sites, aiming at the identification of xenobiotic levels that are able to result in perturbations to the biological pathway that are potentially associated with adverse outcomes. The current study aims at the development of a lifetime PBBK model that covers a large chemical space, coupled with a framework for human biomonitoring (HBM) data assimilation. The methodology developed herein was demonstrated in the case of bisphenol A (BPA), where exposure analysis was based on European HBM data. Based on our calculations, it was found that current exposure levels in Europe are below the temporary Tolerable Daily Intake (t-TDI) of 4 μg/kg_bw/day proposed by the European Food Safety Authority (EFSA). Taking into account age-dependent bioavailability differences, internal exposure was estimated and compared with the biologically effective dose (BED) resulting from translating the EFSA temporary total daily intake (t-TDI) into equivalent internal dose and an alternative internal exposure reference value, namely biological pathway altering dose (BPAD); the use of such a refined exposure metric, showed that environmentally relevant exposure levels are below the concentrations associated with the activation of biological pathways relevant to toxicity based on High Throughput Screening (HTS) in vitro studies.
Pathologic Complete Response (pCR) and Survival of Women with Inflammatory Breast Cancer (IBC): An Analysis Based on Biologic Subtypes and Demographic Characteristics
Authors: Biswas Tithi , Jindal Charulata , Fitzgerald Timothy L. , Efird Jimmy T.
Published: January 2019

In this US-based study of the National Cancer Database (NCDB), we examined 8550 patients diagnosed with non-metastatic, invasive inflammatory breast cancer (IBC) who received surgery from 2004–2013. Patients were grouped into four biologic subtypes (HR+/HER2−, HR+/HER2+, HR−/HER2+, HR−/HER2−). On average, women were 56 years of age at diagnosis and were followed for a median of 3.7 years. The majority were white (80%), had private health insurance (50%), and presented with poorly differentiated tumors (57%). Approximately 46% of the cancers were >5 cm. Most patients underwent mastectomy (94%) and received radiotherapy (71%). Differences by biologic subtypes were observed for grade, lymph node invasion, race, and tumor size (p < 0.0001). Patients experiencing pathologic complete response (pCR, 12%) vs. non-pCR had superior 5-year overall survival (OS) (77% vs. 54%) (p < 0.0001). Survival was poor for triple-negative (TN) tumors (37%) vs. other biologic subtypes (60%) (p < 0.0001). On multivariable analysis, TN-IBC, positive margins, and not receiving either chemotherapy, hormonal therapy or radiotherapy were independently associated with poor 5-year survival (p < 0.0001). In this analysis of IBC, categorized by biologic subtypes, we observed significant differential tumor, patient and treatment characteristics, and OS.
Targeting Multiple Receptors to Increase Checkpoint Blockade Efficacy
Authors: Zahavi David J. , Weiner Louis M.
Published: January 2019

Immune checkpoint blockade therapy is a powerful treatment strategy for many cancer types. Many patients will have limited responses to monotherapy targeted to a single immune checkpoint. Both inhibitory and stimulatory immune checkpoints continue to be discovered. Additionally, many receptors previously identified to play a role in tumor formation and progression are being found to have immunomodulatory components. The success of immunotherapy depends on maximizing pro-anti-tumor immunity while minimizing immunosuppressive signaling. Combining immune checkpoint targeted approaches with each other or with other receptor targets is a promising schema for future therapeutic regimen designs.
Salt Induces Adipogenesis/Lipogenesis and Inflammatory Adipocytokines Secretion in Adipocytes
Authors: Lee Myoungsook , Sorn Sungbin Richard , Lee Yunkyoung , Kang Inhae
Published: January 2019

It is well known that high salt intake is associated with cardiovascular diseases including hypertension. However, the research on the mechanism of obesity due to high salt intake is rare. To evaluate the roles of salt on obesity prevalence, the gene expression of adipogenesis/lipogenesis and adipocytokines secretion according to adipocyte dysfunction were investigated in salt-loading adipocytes. High salt dose-dependently increased the expression of adipogenic/lipogenic genes, such as PPAR-γ, C/EBPα, SREBP1c, ACC, FAS, and aP2, but decreased the gene of lipolysis like AMPK, ultimately resulting in fat accumulation. With SIK-2 and Na+/K+-ATPase activation, salt increased the metabolites involved in the renin-angiotensin-aldosterone system (RAAS) such as ADD1, CYP11β2, and MCR. Increasing insulin dependent insulin receptor substrate (IRS)-signaling, resulting in the insulin resistance, mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) and Akt-mTOR were activated but AMPK(Thr172) was depressed in salt-loading adipocytes. The expression of pro-inflammatory adipocytokines, TNFα, MCP-1, COX-2, IL-17A, IL-6, leptin, and leptin to adiponectin ratio (LAR) were dose-dependently increased by salt treatment. Using the inhibitors of MAPK/ERK, U0126, we found that the crosstalk among the signaling pathways of MAPK/ERK, Akt-mTOR, and the inflammatory adipogenesis can be the possible mechanism of salt-linked obesity. The possibilities of whether the defense mechanisms against high dose of intracellular salts provoke signaling for adipocytes differentiation or interact with surrounding tissues through other pathways will be explored in future research.
Inhibition of Breast Cancer Cell Invasion by Ras Suppressor-1 (RSU-1) Silencing Is Reversed by Growth Differentiation Factor-15 (GDF-15)
Authors: Gkretsi Vasiliki , Louca Maria , Stylianou Andreas , Minadakis George , Spyrou George M. , Stylianopoulos Triantafyllos
Published: January 2019

Extracellular matrix (ECM)-related adhesion proteins are important in metastasis. Ras suppressor-1 (RSU-1), a suppressor of Ras-transformation, is localized to cell–ECM adhesions where it interacts with the Particularly Interesting New Cysteine-Histidine rich protein (PINCH-1), being connected to Integrin Linked Kinase (ILK) and alpha-parvin (PARVA), a direct actin-binding protein. RSU-1 was also found upregulated in metastatic breast cancer (BC) samples and was recently demonstrated to have metastasis-promoting properties. In the present study, we transiently silenced RSU-1 in BC cells, MCF-7 and MDA-MB-231. We found that RSU-1 silencing leads to downregulation of Growth Differentiation Factor-15 (GDF-15), which has been associated with both actin cytoskeleton reorganization and metastasis. RSU-1 silencing also reduced the mRNA expression of PINCH-1 and cell division control protein-42 (Cdc42), while increasing that of ILK and Rac regardless of the presence of GDF-15. However, the downregulation of actin-modulating genes PARVA, RhoA, Rho associated kinase-1 (ROCK-1), and Fascin-1 following RSU-1 depletion was completely reversed by GDF-15 treatment in both cell lines. Moreover, complete rescue of the inhibitory effect of RSU-1 silencing on cell invasion was achieved by GDF-15 treatment, which also correlated with matrix metalloproteinase-2 expression. Finally, using a graph clustering approach, we corroborated our findings. This is the first study providing evidence of a functional association between RSU-1 and GDF-15 with regard to cancer cell invasion.
Protective Effects and Mechanisms of N-Phenethyl Caffeamide from UVA-Induced Skin Damage in Human Epidermal Keratinocytes through Nrf2/HO-1 Regulation
Authors: Chu Yin , Wu Po-Yuan , Chen Chien-Wen , Lyu Jia-Ling , Liu Yi-Jung , Wen Kuo-Ching , Lin Chien-Yih , Kuo Yueh-Hsiung , Chiang Hsiu-Mei
Published: January 2019

The skin provides an effective barrier against physical, chemical, and microbial invasion; however, overexposure to ultraviolet (UV) radiation causes excessive cellular oxidative stress, which leads to skin damage, DNA damage, mutations, and skin cancer. This study investigated the protective effects of N-phenethyl caffeamide (K36) from UVA damage on human epidermal keratinocytes. We found that K36 reduced UVA-induced intracellular reactive oxygen species (ROS) production and induced the expression of the intrinsic antioxidant enzyme heme oxygenase-1 (HO-1) by increasing the translocation of nuclear factor erythroid 2–related factor 2 (Nrf2). K36 could inhibit the phosphorylation of extracellular-signal-regulated kinase (ERK) and c-Jun N-terminal kinases (JNK) and reduce UVA-induced matrix metalloproteinase (MMP)-1 and MMP-2 overexpression; it could also elevate the expression of tissue inhibitors of metalloproteinases (TIMP). In addition, K36 ameliorated 8-hydroxy-2′-deoxyguanosine (8-OHdG) induced by UVA irradiation. Furthermore, K36 could downregulate the expression of inducible nitric oxide synthase (iNOS) and interleukin-6 (IL-6) and the subsequent production of nitric oxide (NO) and prostaglandin E2 (PGE2). Based on our findings, K36 possessed potent antioxidant, anti-inflammatory, antiphotodamage, and even antiphotocarcinogenesis activities. Thus, K36 has the potential to be used to multifunctional skin care products and drugs.
Profiled Ion Exchange Membranes: A Comprehensible Review
Authors: Pawlowski Sylwin , Crespo João G. , Velizarov Svetlozar
Published: January 2019

Profiled membranes (also known as corrugated membranes, micro-structured membranes, patterned membranes, membranes with designed topography or notched membranes) are gaining increasing academic and industrial attention and recognition as a viable alternative to flat membranes. So far, profiled ion exchange membranes have shown to significantly improve the performance of reverse electrodialysis (RED), and particularly, electrodialysis (ED) by eliminating the spacer shadow effect and by inducing hydrodynamic changes, leading to ion transport rate enhancement. The beneficial effects of profiled ion exchange membranes are strongly dependent on the shape of their profiles (corrugations/patterns) as well as on the flow rate and salts’ concentration in the feed streams. The enormous degree of freedom to create new profile geometries offers an exciting opportunity to improve even more their performance. Additionally, the advent of new manufacturing methods in the membrane field, such as 3D printing, is anticipated to allow a faster and an easier way to create profiled membranes with different and complex geometries.
Oversecretion and Overexpression of Nicotinamide Phosphoribosyltransferase/Pre-B Colony-Enhancing Factor/Visfatin in Inflammatory Bowel Disease Reflects the Disease Activity, Severity of Inflammatory Response and Hypoxia
Authors: Neubauer Katarzyna , Bednarz-Misa Iwona , Walecka-Zacharska Ewa , Wierzbicki Jaroslaw , Agrawal Anil , Gamian Andrzej , Krzystek-Korpacka Malgorzata
Published: January 2019

Nicotinamide phosphoribosyltransferase’s (Nampt) association with inflammatory bowel disease (IBD) is unclear. The study was aimed at unraveling Nampt’s clinical and diagnostic relevance. The serum concentration (Luminex-xMAP® technology) was measured in 113 patients with Crohn’s disease (CD), 127 with ulcerative colitis (UC) and 60 non-IBD controls: 40 healthy individuals and 20 with irritable bowel syndrome (IBS). The leukocyte (44 CD/37 UC/19 IBS) and bowel expression (186 samples) was also evaluated (RT-qPCR). All were referred to IBD phenotype, activity, treatment, and inflammatory/nutritional/angiogenic/hypoxia indices. Serum-Nampt and leukocyte-Nampt were positively correlated and were more elevated in active-IBD than in IBS, with leukocyte-Nampt being a fair differential marker. Serum-Nampt in UC positively correlated with its clinical and endoscopic activity as well as with pro-inflammatory cytokines. Serum-Nampt ≤1.54 ng/mL was a good indicator of mucosal healing. The expression of Nampt was up-regulated both in inflamed and quiescent colon and reflected, similarly to leukocyte-Nampt, the clinical activity of IBD. Bowel-Nampt was independently associated with IL1B and hypoxia-inducible factor 1α (HIF1A) expression in inflamed bowel but with FGF2 expression in quiescent bowel. In summary, Nampt’s elevation in IBD at local and systemic levels, and protein and mRNA levels, reflects IBD activity and is associated with inflammation, hypoxia (active) and tissue repair (inactive disease).
The Impact of Exchange Rate Volatility on Exports in Vietnam: A Bounds Testing Approach
Authors: Thuy Vinh Nguyen Thi , Thuy Duong Trinh Thi
Published: January 2019

This paper investigates the impact of exchange rate volatility on exports in Vietnam using quarterly data from the first quarter of 2000 to the fourth quarter of 2014. The paper applies the autoregressive distributed lag (ARDL) bounds testing approach to the analysis of level relationships between effective exchange rate volatility and exports. Using the demand function of exports, the paper also considers the effect of depreciation and foreign income on exports of Vietnam. The results show that exchange rate volatility negatively affects the export volume in the long run, as expected. A depreciation of the domestic currency affects exports negatively in the short run, but positively in the long run, consistent with the J curve effect. Surprisingly, an increase in the real income of a foreign country actually decreases Vietnamese export volume. These findings suggest some policy implications in managing the exchange rate system and promoting exports of Vietnam.
Tunable Perfect THz Absorber Based on a Stretchable Ultrathin Carbon-Polymer Bilayer
Authors: Paddubskaya Alesia , Demidenko Marina , Batrakov Konstantin , Valušis Gintaras , Kaplas Tommi , Svirko Yuri , Kuzhir Polina
Published: January 2019

By exploring the Salisbury screen approach, we propose and demonstrate a thin film absorber of terahertz (THz) radiation. The absorber is comprised of a less than 100 nm thick layer of pyrolytic carbon deposited on a stretchable polydimethylsiloxane (PDMS) film followed by the metal film. We demonstrate that being overall less than 200 microns thick, such a sandwich structure absorbs resonantly up to 99.9%of the incident THz radiation, and that the absorption resonance is determined by the polymer thickness, which can be adjusted by stretching.
Investigations into Ti-15Mo-W Alloys Developed for Medical Applications
Authors: Buzatu Mihai , Geantă Victor , Ştefănoiu Radu , Buţu Mihai , Petrescu Mircea-Ionuţ , Buzatu Mihai , Antoniac Iulian , Iacob Gheorghe , Niculescu Florentina , Ghica Ştefan-Ioan , Moldovan Horaţiu
Published: January 2019

The β-Ti alloys have attracted the attention of researchers due to their excellent properties and their remarkable biocompatibility. The present study evaluated the mechanical behavior analysis (hardness, compressive strength, and modulus of elasticity) of the Ti-15Mo-W system. For experimental research, we chose the TiMo15 biocompatible alloy as a starting material. In order to improve the mechanical properties, we added tungsten amounts of 3.88 to 12.20 wt.% and analyzed the results obtained. The successive melting of the samples was done using a vacuum arc furnace in a copper crucible cooled with water. Following micro-structural investigations, we found this alloy possessed a homogeneous structure and showed β-phase predominance. The investigated alloys have good mechanical properties—the mean Vickers micro-hardness values are between 251 to 321 HV, the compressive strength values range from 717 to 921 MPa, and the modulus of elasticity is between 17.86 and 45.35 GPa. These results are compatible to the requirements of a metallic material for medical applications as artificial implant devices.
Synthesis, Nanomechanical Characterization and Biocompatibility of a Chitosan-Graft-Poly(ε-caprolactone) Copolymer for Soft Tissue Regeneration
Authors: Charitidis Costas A. , Dragatogiannis Dimitrios A. , Milioni Eleni , Kaliva Maria , Vamvakaki Maria , Chatzinikolaidou Maria
Published: January 2019

Tissue regeneration necessitates the development of appropriate scaffolds that facilitate cell growth and tissue development by providing a suitable substrate for cell attachment, proliferation, and differentiation. The optimized scaffolds should be biocompatible, biodegradable, and exhibit proper mechanical behavior. In the present study, the nanomechanical behavior of a chitosan-graft-poly(ε-caprolactone) copolymer, in hydrated and dry state, was investigated and compared to those of the individual homopolymers, chitosan (CS) and poly(ε-caprolactone) (PCL). Hardness and elastic modulus values were calculated, and the time-dependent behavior of the samples was studied. Submersion of PCL and the graft copolymer in α-MEM suggested the deterioration of the measured mechanical properties as a result of the samples’ degradation. However, even after three days of degradation, the graft copolymer presented sufficient mechanical strength and elastic properties, which resemble those reported for soft tissues. The in vitro biological evaluation of the material clearly demonstrated that the CS-g-PCL copolymer supports the growth of Wharton’s jelly mesenchymal stem cells and tissue formation with a simultaneous material degradation. Both the mechanical and biological data render the CS-g-PCL copolymer appropriate as a scaffold in a cell-laden construct for soft tissue engineering.
Robust Control of Small Turbojet Engines
Authors: Andoga Rudolf , Főző Ladislav , Kovács Radovan , Beneda Károly , Moravec Tomáš , Schreiner Michal
Published: January 2019

Modern turbojet engines mainly use computerized digital engine control systems. This opens the way for application of advanced algorithms aimed at increasing their operational efficiency and safety. The theory of robust control is a set of methods known for good results in complex control tasks, making them ideal candidates for application in the current turbojet engine control units. Different methodologies in the design of robust controllers, utilizing a small turbojet engine with variable exhaust nozzle designated as iSTC-21v, were therefore investigated in the article. The resulting controllers were evaluated for efficiency in laboratory conditions. The aim was to find a suitable approach and design method for robust controllers, taking into account the limitations and specifics of a real turbojet engine and its hardware, contrary to most studies which have used only simulated environments. The article shows the most effective approach in the design of robust controllers and the resulting speed controllers for a class of small turbojet engines, which can be applied in a discrete digital control environment.
Distance and Adjacency Energies of Multi-Level Wheel Networks
Authors: Liu Jia-Bao , Munir Mobeen , Yousaf Amina , Naseem Asim , Ayub Khudaija
Published: January 2019

Energies of molecular graphs have various applications in chemistry, polymerization, computer networking and pharmacy. In this paper, we give general closed forms of distance and adjacency energies of generalized wheel networks W n , m . Consequently, we give these results for classical wheel graphs. We also give pictorial dependencies of energies on the involved parameters m ≥ 3 and n .
Electrodialysis Extraction of Pufferfish Skin (Takifugu flavidus): A Promising Source of Collagen
Authors: Chen Junde , Li Min , Yi Ruizao , Bai Kaikai , Wang Guangyu , Tan Ran , Sun Shanshan , Xu Nuohua
Published: January 2019

Collagen is widely used in drugs, biomaterials, foods, and cosmetics. By-products of the fishing industry are rich sources of collagen, which can be used as an alternative to collagen traditionally harvested from land mammals. However, commercial applications of fish-based collagen are limited by the low efficiency, low productivity, and low sustainability of the extraction process. This study applied a new technique (electrodialysis) for the extraction of Takifugu flavidus skin collagen. We found electrodialysis to have better economic and environmental outcomes than traditional dialysis as it significantly reduced the purification time and wastewater (~95%) while maintaining high extraction yield (67.3 ± 1.3 g/100 g dry weight, p < 0.05). SDS-PAGE, amino acid composition analysis, and spectrophotometric characterization indicated that electrodialysis treatment retained the physicochemical properties of T. flavidus collagen. Heavy metals and tetrodotoxin analyses indicated the safety of T. flavidus collagen. Notably, the collagen had similar thermal stability to calf skin collagen, with the maximum transition temperature and denaturation temperature of 41.8 ± 0.35 and 28.4 ± 2.5 °C, respectively. All evidence suggests that electrodialysis is a promising technique for extracting collagen in the fishing industry and that T. flavidus skin collagen could serve as an alternative source of collagen to meet the increasing demand from consumers.