bluuebunny/crossref_metadata_2025 huggingface dataset:
Universal Shapes? Analysis of the Shape of Antarctic Tafoni
Authors: Inkpen Rob , Hall Kevin
Published: April 2019

Using dimensional data from over 700 tafoni in Antarctica, this paper identifies how the dimensionless ratios of width/length (W/L) and depth/length (D/L) vary with tafoni length. The analysis suggests that these ratios do tend to converge to values that are similar to those found for fragments produced by brittle fracture and fragmentation. Dividing the data into quintiles and deciles, it is possible to assess how tafoni size and shape change as tafoni length increases. Smaller tafoni do tend to have a rounder plan form which rapidly changes as tafoni length increases towards the W/L ratio of 0.67. It is suggested that initial tafoni development is limited by the conditions set out in a recent mathematical model of tafoni development. This model focuses on tafoni development through the interactions of variable rock strength and the varying concentration gradient of a corrosive agent. Erosion involves the removal of relatively small sections of rock and is analogous to a continuous erosional process. This model produces tafoni of relatively circular plan form. Above a certain tafoni length it is suggested that processes associated with brittle fracture begin to dominant the development and shape of tafoni.
Studying the Evolving Knowledge of Adverse Drug Reactions in Order to Facilitate the Rational Use of Medicines in Paediatric Patients
Authors: Star Kristina , Choonara Imti
Published: April 2019

Pharmacovigilance, which is the science and activities relating to the detection, assessment, understanding and prevention of adverse effects or any other possible drug-related problems, generates knowledge to facilitate the rational use of medicines. When a medicine is first marketed, there is limited information on adverse drug reactions (ADRs), especially in paediatrics, where medicines are less likely to have been extensively studied. Knowledge in drug safety is built up over time when more (in number, and more heterogeneous) patients are treated than were studied in the randomised controlled trials preceding the marketing of a medicine. Previously not recognised ADRs are often initially described in case reports and case series. Prospective cohort studies are useful in determining the incidence and risk factors of common ADRs. Case series and pharmacovigilance reporting systems have been useful in identifying previously unknown uncommon ADRs and risk factors for specific ADRs. This brief review provides examples that illustrate how various study designs and data sources contribute to the evolving knowledge of ADRs that is essential to help develop guidelines and improve the rational use of medicines.
ORION—Art Collections and Collectors in Portugal
Authors: Mariz Vera , Salema de Carvalho Rosário , Cabral Fernando , Neto Maria , Moura Soares Clara , Jorge Natália
Published: April 2019

ORION is a digital art history research-oriented project focused on the study of art collections and collectors in Portugal, supported on a relational database management system. Besides the obvious advantage of organizing and systematizing an enormous amount of information, promoting its analysis, this database was specifically designed to highlight the relationships between data. Its relational capacity is not only one of the most relevant features of ORION, but a differentiating quality, one step forward in comparison to other international databases and studies that use digital methodologies. This article discusses the methods and the advantages of using ORION in research related to the history of collecting, art markets and provenance of art objects in Portugal, where it is the very first time that an approach such as this is intended, looking for a systematization of data that paves the way to the emergence of new research questions. Furthermore, and because ORION aims to share the data and knowledge with other projects, institutions and researchers, the database uses different international standards, such as data structure (CIDOC-OIC and Getty-CDWA), controlled vocabulary (Iconclass, Art and Architecture Thesaurus (AAT), Thesaurus of Geographic Names (TGN), and Union List of Artist Names (ULAN)) and communication and exchange of information (CIDOC-CRM).
Effect of Insurance-Related Factors on the Association between Flooding and Mental Health Outcomes
Authors: Mulchandani Ranya , Smith Melissa , Armstrong Ben ,   English National Study of Flooding and Health Study Group, Beck Charles R , Oliver Isabel
Published: April 2019

Floods are a significant public health problem linked with increased psychological morbidity. We aimed to investigate the effect of insurance-related factors on the association between flooding and probable mental health outcomes. We performed a secondary analysis of cross-sectional survey data from the English National Study of Flooding and Health (NSFH) collected two years after an initial flooding event in 2013-14. Our analysis focused on 851 respondents who experienced flooding or disruption. Multivariable logistic regression models were run for each exposure group. Among those whose homes had been flooded, not having household insurance was associated with increased odds of all outcomes compared to those with household insurance, significantly so for post-traumatic stress disorder (PTSD) (aOR 4.31, 95% CI 1.31–14.20). Those who reported severe stress due to insurance issues had increased odds of probable depression (aOR 11.08, 95% CI 1.11–110.30), anxiety (aOR 4.48, 95% CI 1.02–19.70) and PTSD (aOR 7.95, 95% CI 2.10–30.1) compared to those reporting no/mild stress. The study suggests there is increased psychological morbidity amongst the uninsured and those who report feeling severe stress as a result of insurance issues associated with flooding. Services should be prepared to support communities through insurance processes, to reduce probable mental health morbidity following a flood event.
The Nature of Job Crafting: Positive and Negative Relations with Job Satisfaction and Work-Family Conflict
Authors: Zito Margherita , Colombo Lara , Borgogni Laura , Callea Antonino , Cenciotti Roberto , Ingusci Emanuela , Cortese Claudio Giovanni
Published: April 2019

This study investigated job crafting as mediator and its relation with job satisfaction and work-family conflict, considering job autonomy as antecedent. The research involved 389 participants working in a public organization. A structural equations model was estimated revealing that job autonomy is positively associated with job crafting and job satisfaction, and negatively associated with work-family conflict. Job crafting is positively related with job satisfaction and work-family conflict, as adverse effect of job crafting. As regards mediated effects, results show positive associations between job autonomy and both job satisfaction and work-family conflict through job crafting. This study contributes to literature, considering positive and negative outcomes, covering the lacking literature on job crafting and work-family conflict, and suggesting implications for employees’ well-being.
Food Cravings and Eating: The Role of Experiential Avoidance
Authors: Fahrenkamp Amy J. , Darling Katherine E. , Ruzicka Elizabeth B. , Sato Amy F.
Published: April 2019

Food cravings have been associated with problematic eating behaviors, such as emotional eating. Late adolescence is an important developmental period to examine this association, as late adolescents have greater independence in food choices as well as potentially higher demands during a transitional period of their lives. Mechanisms underlying the association between food cravings and problematic eating remain unclear. This study examined whether experiential avoidance (EA) may be one possible mechanism mediating the association between higher levels of food cravings and problematic eating behaviors. Late adolescents (n = 174) completed measures assessing EA, food cravings, and three problematic eating behaviors: emotional eating, cognitive restraint, and uncontrolled eating. Height and weight were measured objectively to calculate body mass index (BMI). Food cravings were positively associated with emotional eating and mediated by EA. EA also significantly mediated the association between greater cognitive restraint and greater food cravings. No significant mediation was detected for food cravings and uncontrolled eating. Future research may consider EA as a treatment target in intervention strategies for late adolescents seeking to decrease emotional or restrained eating behaviors.
Review of Methodologies for Assessing Sustainable Diets and Potential for Development of Harmonised Indicators
Authors: Eme Paul Eze , Douwes Jeroen , Kim Nicholas , Foliaki Sunia , Burlingame Barbara
Published: April 2019

The underlying values and priorities that drive policy responses depend largely on the constructs that researchers and decision makers select to measure and the metrics used. Despite much recent attention being given to sustainable diets and food systems and to the importance of clearly measuring sustainability to meet targets, to achieve goals, and to appraise dietary and environmental policies, it is not commonly agreed how the different indicators of sustainable diets are assessed. The evidence base for assessment of these indicators are frequently weak, fragmented, and arbitrary. The aim of this paper was to compare a range of published methods and indicators for assessing sustainable diets and food systems in order to harmonise them. Keyword and reference searches were performed in PubMed, Scopus, CAB Abstracts, and Web of Knowledge. Fifty-two studies (21 proposed methods and 31 used methods) that combined environment, nutrition and health, and socioeconomic aspects of sustainable diets were reviewed. The majority (over 90%) of the studies focused on high-income countries. Twenty-eight studies assessed the environmental effects of different dietary practices, eight of the studies examined the nutrition and health indicators used for assessing sustainable food systems, and seven studies assessed the social and economic costs of diets. A classification of the elements was developed, and common elements are proposed for standardizing. These elements were categorized into nutrition and health indicators, environment indicators, and socioeconomic indicators. Standardized or harmonized indicators can be used for consistency and applicability purposes and to support, implement, and monitor relevant policies.
Role of Emerging Environmental Risk Factors in Thyroid Cancer: A Brief Review
Authors: Fiore Maria , Oliveri Conti Gea , Caltabiano Rosario , Buffone Antonino , Zuccarello Pietro , Cormaci Livia , Cannizzaro Matteo Angelo , Ferrante Margherita
Published: April 2019

Environmental factors are recognized as risk factors of thyroid cancer in humans. Exposure to radiation, both from nuclear weapon or fallout or medical radiation, and to some organic and inorganic chemical toxicants represent a worldwide public health issue for their proven carcinogenicity. Halogenated compounds, such as organochlorines and pesticides, are able to disrupt thyroid function. Polychlorinated biphenyls and their metabolites and polybrominated diethyl ethers bind to thyroid, transport proteins, replace thyroxin, and disrupt thyroid function as phthalates and bisphenolates do, highly mimicking thyroid hormones. A better knowledge of environmental risks represents a very important tool for cancer prevention through true risks prevention and management. This approach is very important because of the epigenetic origin’s theory of cancer. Therefore, the aim of this review was study the association between environmental agents and thyroid cancer promotion.
Non-Ionizing Radiation in Swedish Health Care—Exposure and Safety Aspects
Authors: Hansson Mild Kjell , Lundström Ronnie , Wilén Jonna
Published: April 2019

The main aim of the study was to identify and describe methods using non-ionizing radiation (NIR) such as electromagnetic fields (EMF) and optical radiation in Swedish health care. By examining anticipated exposure levels and by identifying possible health hazards we also aimed to recognize knowledge gaps in the field. NIR is mainly used in health care for diagnosis and therapy. Three applications were identified where acute effects cannot be ruled out: magnetic resonance imaging (MRI), transcranial magnetic stimulation (TMS) and electrosurgery. When using optical radiation, such as class 3 and 4 lasers for therapy or surgical procedures and ultra-violet light for therapy, acute effects such as unintentional burns, photo reactions, erythema and effects on the eyes need to be avoided. There is a need for more knowledge regarding long-term effects of MRI as well as on the combination of different NIR exposures. Based on literature and after consulting staff we conclude that the health care professionals’ knowledge about the risks and safety measures should be improved and that there is a need for clear, evidence-based information from reliable sources, and it should be obvious to the user which source to address.
Design of Temperature Insurance Index and Risk Zonation for Single-Season Rice in Response to High-Temperature and Low-Temperature Damage: A Case Study of Jiangsu Province, China
Authors: Guo Ji , Jin Jiajia , Tang Yinshan , Wu Xianhua
Published: April 2019

Disaster insurance is an important tool for achieving sustainable development in modern agriculture. However, in China, the design of such insurance indexes is far from sufficient. In this paper, the single-season rice in Jiangsu Province of China is taken as an example to design the high-temperature damage index in summer and the low-temperature damage index in autumn to construct the formula calculating the weather output and single-season rice yield reduction. The daily highest, lowest and average temperatures between 1999 and 2015 are selected as main variables for the temperature disaster index to quantitatively analyze the relationship between the temperature index and the yield reduction rate of the single-season rice. The temperature disaster index can be put into the relevant model to obtain the yield reduction rate of the year and determine whether to pay the indemnity. Then, the burn analysis is used to determine the insurance premium rate for all cities in Jiangsu Province under four-level deductibles, and the insurance premium rate can be used for the risk division of the Province. The research provides some insights for the design of agricultural weather insurance products, and the empirical results provide a reference for the design of similar single-season rice temperature index insurance products.
Physiological Changes of Parachlorella Kessleri TY02 in Lipid Accumulation under Nitrogen Stress
Authors: Gao Yifan , Feng Jia , Lv Junping , Liu Qi , Nan Fangru , Liu Xudong , Xie Shulian
Published: April 2019

In order to study the effects of nitrogen stress on the lipid synthesis of Parachlorella kessleri TY02 and to understand the changes in growth, photosynthetic pigments, total protein and total carbohydrate contents during lipid accumulation, the cells of the strain were cultured in nitrogen-deficient (N−) and nitrogen-rich (N+) media for one week. Changes in cell growth, chlorophyll content, chlorophyll fluorescence parameters, neutral lipid and total lipid content, total protein content and total carbohydrate content were measured and analyzed. The results showed that, under nitrogen stress, the algal strain grew slowly, and chlorophyll and total protein contents decreased, while total carbohydrate and total lipid contents increased. This indicated that, under nitrogen stress, most of the carbon flowed to the synthesis of lipids and carbohydrates. Meanwhile, reducing the nitrogen content was a relatively economical and easy to operate method of promoting lipid accumulation.
The Construction and Optimization of Ecological Security Pattern in the Harbin-Changchun Urban Agglomeration, China
Authors: Guo Rong , Wu Tong , Liu Mengran , Huang Mengshi , Stendardo Luigi , Zhang Yutong
Published: April 2019

Urban agglomerations have become a new geographical unit in China, breaking the administrative fortresses between cities, which means that the population and economic activities between cities will become more intensive in the future. Constructing and optimizing the ecological security pattern of urban agglomerations is important for promoting harmonious social-economic development and ecological protection. Using the Harbin-Changchun urban agglomeration as a case study, we have identified ecological sources based on the evaluation of ecosystem functions. Based on the resistance surface modified by nighttime light (NTL) data, the potential ecological corridors were identified using the least-cost path method, and key ecological corridors were extracted using the gravity model. By combining 15 ecological sources, 119 corridors, 3 buffer zones, and 77 ecological nodes, the ecological security pattern (ESP) was constructed. The main land-use types composed of ecological sources and corridors are forest land, cultivated land, grassland, and water areas. Some ecological sources are occupied by construction, while unused land has the potential for ecological development. The ecological corridors in the central region are distributed circularly and extend to southeast side in the form of tree branches with the Songhua River as the central axis. Finally, this study proposes an optimizing pattern with “four belts, four zones, one axis, nine corridors, ten clusters and multi-centers” to provide decision makers with spatial strategies with respect to the conflicts between urban development and ecological protection during rapid urbanization.
Structure-Guided Immobilization of an Evolved Unspecific Peroxygenase
Authors: Molina-Espeja Patricia , Santos-Moriano Paloma , García-Ruiz Eva , Ballesteros Antonio , Plou Francisco J. , Alcalde Miguel
Published: April 2019

Unspecific peroxygenases (UPOs) are highly promiscuous biocatalyst with self-sufficient mono(per)oxygenase activity. A laboratory-evolved UPO secreted by yeast was covalently immobilized in activated carriers through one-point attachment. In order to maintain the desired orientation without compromising the enzyme’s activity, the S221C mutation was introduced at the surface of the enzyme, enabling a single disulfide bridge to be established between the support and the protein. Fluorescence confocal microscopy demonstrated the homogeneous distribution of the enzyme, regardless of the chemical nature of the carrier. This immobilized biocatalyst was characterized biochemically opening an exciting avenue for research into applied synthetic chemistry.
Human Multilineage 3D Spheroids as a Model of Liver Steatosis and Fibrosis
Authors: Pingitore Piero , Sasidharan Kavitha , Ekstrand Matias , Prill Sebastian , Lindén Daniel , Romeo Stefano
Published: April 2019

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disorder in western countries. Despite the high prevalence of NAFLD, the underlying biology of the disease progression is not clear, and there are no approved drugs to treat non-alcoholic steatohepatitis (NASH), the most advanced form of the disease. Thus, there is an urgent need for developing advanced in vitro human cellular systems to study disease mechanisms and drug responses. We attempted to create an organoid system genetically predisposed to NAFLD and to induce steatosis and fibrosis in it by adding free fatty acids. We used multilineage 3D spheroids composed by hepatocytes (HepG2) and hepatic stellate cells (LX-2) with a physiological ratio (24:1). HepG2 and LX-2 cells are homozygotes for the PNPLA3 I148M sequence variant, the strongest genetic determinant of NAFLD. We demonstrate that hepatic stellate cells facilitate the compactness of 3D spheroids. Then, we show that the spheroids develop accumulations of fat and collagen upon exposure to free fatty acids. Finally, this accumulation was rescued by incubating spheroids with liraglutide or elafibranor, drugs that are in clinical trials for the treatment of NASH. In conclusion, we have established a simple, easy to handle, in vitro model of genetically induced NAFLD consisting of multilineage 3D spheroids. This tool may be used to understand molecular mechanisms involved in the early stages of fibrogenesis induced by lipid accumulation. Moreover, it may be used to identify new compounds to treat NASH using high-throughput drug screening.
Molecular Mechanisms Controlled by mTOR in Male Reproductive System
Authors: Moreira Bruno P. , Oliveira Pedro F. , Alves Marco G.
Published: April 2019

In recent years, the mammalian target of rapamycin (mTOR) has emerged as a master integrator of upstream inputs, such as amino acids, growth factors and insulin availability, energy status and many others. The integration of these signals promotes a response through several downstream effectors that regulate protein synthesis, glucose metabolism and cytoskeleton organization, among others. All these biological processes are essential for male fertility, thus it is not surprising that novel molecular mechanisms controlled by mTOR in the male reproductive tract have been described. Indeed, since the first clinical evidence showed that men taking rapamycin were infertile, several studies have evidenced distinct roles for mTOR in spermatogenesis. However, there is a lack of consensus whether mTOR inhibition, which remains the experimental approach that originates the majority of available data, has a negative or positive impact on male reproductive health. Herein we discuss the latest findings concerning mTOR activity in testes, particularly its role on spermatogonial stem cell (SSC) maintenance and differentiation, as well as in the physiology of Sertoli cells (SCs), responsible for blood–testis barrier maintenance/restructuring and the nutritional support of spermatogenesis. Taken together, these recent advances highlight a crucial role for mTOR in determining the male reproductive potential.
Prediction Medicine: Biomarkers, Risk Calculators and Magnetic Resonance Imaging as Risk Stratification Tools in Prostate Cancer Diagnosis
Authors: Osses Daniël F. , Roobol Monique J. , Schoots Ivo G.
Published: April 2019

This review discusses the most recent evidence for currently available risk stratification tools in the detection of clinically significant prostate cancer (csPCa), and evaluates diagnostic strategies that combine these tools. Novel blood biomarkers, such as the Prostate Health Index (PHI) and 4Kscore, show similar ability to predict csPCa. Prostate cancer antigen 3 (PCA3) is a urinary biomarker that has inferior prediction of csPCa compared to PHI, but may be combined with other markers like TMPRSS2-ERG to improve its performance. Original risk calculators (RCs) have the advantage of incorporating easy to retrieve clinical variables and being freely accessible as a web tool/mobile application. RCs perform similarly well as most novel biomarkers. New promising risk models including novel (genetic) markers are the SelectMDx and Stockholm-3 model (S3M). Prostate magnetic resonance imaging (MRI) has evolved as an appealing tool in the diagnostic arsenal with even stratifying abilities, including in the initial biopsy setting. Merging biomarkers, RCs and MRI results in higher performances than their use as standalone tests. In the current era of prostate MRI, the way forward seems to be multivariable risk assessment based on blood and clinical parameters, potentially extended with information from urine samples, as a triaging test for the selection of candidates for MRI and biopsy.
Poly(ADP-Ribose) Polymerases in Plants and Their Human Counterparts: Parallels and Peculiarities
Authors: Rissel Dagmar , Peiter Edgar
Published: April 2019

Poly(ADP-ribosyl)ation is a rapid and transient post-translational protein modification that was described first in mammalian cells. Activated by the sensing of DNA strand breaks, poly(ADP-ribose)polymerase1 (PARP1) transfers ADP-ribose units onto itself and other target proteins using NAD+ as a substrate. Subsequently, DNA damage responses and other cellular responses are initiated. In plants, poly(ADP-ribose) polymerases (PARPs) have also been implicated in responses to DNA damage. The Arabidopsis genome contains three canonical PARP genes, the nomenclature of which has been uncoordinated in the past. Albeit assumptions concerning the function and roles of PARP proteins in planta have often been inferred from homology and structural conservation between plant PARPs and their mammalian counterparts, plant-specific roles have become apparent. In particular, PARPs have been linked to stress responses of plants. A negative role under abiotic stress has been inferred from studies in which a genetic or, more commonly, pharmacological inhibition of PARP activity improved the performance of stressed plants; in response to pathogen-associated molecular patterns, a positive role has been suggested. However, reports have been inconsistent, and the effects of PARP inhibitors appear to be more robust than the genetic abolition of PARP gene expression, indicating the presence of alternative targets of those drugs. Collectively, recent evidence suggests a conditionality of stress-related phenotypes of parp mutants and calls for a reconsideration of PARP inhibitor studies on plants. This review critically summarizes our current understanding of poly(ADP-ribosylation) and PARP proteins in plants, highlighting similarities and differences to human PARPs, areas of controversy, and requirements for future studies.
Concomitant Expression of Prolactin Receptor and TGFβ Receptors in Breast Cancer: Association with Less Aggressive Phenotype and Favorable Patient Outcome
Authors: Hachim Ibrahim Y. , López-Ozuna Vanessa M. , Hachim Mahmood Y. , Lebrun Jean-Jacques , Ali Suhad
Published: April 2019

The epithelial–mesenchymal transition (EMT) process is known to play an essential role in tumor progression, metastasis and resistance to therapy. This report evaluated the prognostic value of co-expression of the receptor for prolactin (PRLR), a suppressor of EMT, and the receptors for transforming growth factor β (TGFβRI and TGFβRII), an inducer of EMT, in association with different clinicopathological parameters using TMA of 102 breast cancer patients and publicly available data on breast cancer patients. Interestingly, the results revealed that malignant tissues had significantly lower levels of concomitant protein expression of these receptors in comparison to normal/benign breast tissue. In addition, a higher level of concomitant expression was also observed in less aggressive breast cancer phenotypes, including low grade tumors, luminal breast cancer subtype, and less advanced stages of the disease (lymph node negative and early stages). Moreover, the results also showed that the expression of a gene signature composed of PRLR/TGFβRI/TGFβRII correlates more with differentiated grade I tumors, and identified a subset of patients showing better survival outcomes evident in luminal B and HER-2 enriched molecular subtypes. Together, these results indicate that loss of the co-expression of PRLR, TGFβRI and TGFβRII is indicative of aggressiveness and poor patient survival outcomes in breast cancer.
Calcium Release from Endoplasmic Reticulum Involves Calmodulin-Mediated NADPH Oxidase-Derived Reactive Oxygen Species Production in Endothelial Cells
Authors: Sakurada Ryugo , Odagiri Keiichi , Hakamata Akio , Kamiya Chiaki , Wei Jiazhang , Watanabe Hiroshi
Published: April 2019

Background: Previous studies demonstrated that calcium/calmodulin (Ca2+/CaM) activates nicotinamide adenine dinucleotide phosphate oxidases (NOX). In endothelial cells, the elevation of intracellular Ca2+ level consists of two components: Ca2+ mobilization from the endoplasmic reticulum (ER) and the subsequent store-operated Ca2+ entry. However, little is known about which component of Ca2+ increase is required to activate NOX in endothelial cells. Here, we investigated the mechanism that regulates NOX-derived reactive oxygen species (ROS) production via a Ca2+/CaM-dependent pathway. Methods: We measured ROS production using a fluorescent indicator in endothelial cells and performed phosphorylation assays. Results: Bradykinin (BK) increased NOX-derived cytosolic ROS. When cells were exposed to BK with either a nominal Ca2+-free or 1 mM of extracellular Ca2+ concentration modified Tyrode’s solution, no difference in BK-induced ROS production was observed; however, chelating of cytosolic Ca2+ by BAPTA/AM or the depletion of ER Ca2+ contents by thapsigargin eliminated BK-induced ROS production. BK-induced ROS production was inhibited by a CaM inhibitor; however, a Ca2+/CaM-dependent protein kinase II (CaMKII) inhibitor did not affect BK-induced ROS production. Furthermore, BK stimulation did not increase phosphorylation of NOX2, NOX4, and NOX5. Conclusions: BK-induced NOX-derived ROS production was mediated via a Ca2+/CaM-dependent pathway; however, it was independent from NOX phosphorylation. This was strictly regulated by ER Ca2+ contents.
Assessing the Damage Tolerance of Out of Autoclave Manufactured Carbon Fibre Reinforced Polymers Modified with Multi-Walled Carbon Nanotubes
Authors: Dimoka Polyxeni , Psarras Spyridon , Kostagiannakopoulou Christine , Kostopoulos Vassilis
Published: April 2019

The present study aims to investigate the influence of multi-walled carbon nanotubes (MWCNTs) on the damage tolerance after impact (CAI) of the development of Out of Autoclave (OoA) carbon fibre reinforced polymer (CFRP) laminates. The introduction of MWCNTs into the structure of CFRPs has been succeeded by adding carbon nanotube-enriched sizing agent for the pre-treatment of the fibre preform and using an in-house developed methodology that can be easily scaled up. The modified CFRPs laminates with 1.5 wt.% MWCNTs were subjected to low velocity impact at three impact energy levels (8, 15 and 30 J) and directly compared with the unmodified laminates. In terms of the CFRPs impact performance, compressive strength of nanomodified composites was improved for all energy levels compared to the reference material. The test results obtained from C-scan analysis of nano-modified specimens showed that the delamination area after the impact is mainly reduced, without the degradation of compressive strength and stiffness, indicating a potential improvement of damage tolerance compared to the reference material. SEM analysis of fracture surfaces revealed the additional energy dissipation mechanisms; pulled-out carbon nanotubes which is the main reason for the improved damage tolerance of the multifunctional composites.
Influence of Fiber Volume Content on Thermal Conductivity in Transverse and Fiber Direction of Carbon Fiber-Reinforced Epoxy Laminates
Authors: Bard Simon , Schönl Florian , Demleitner Martin , Altstädt Volker
Published: April 2019

Thermal conductivity is an important material property for thermo-mechanical calculations, as mechanical properties strongly depend on the temperature and heat distribution in the manufactured parts. Although several suggestions for approximation formulae have been made, existing experimental data are rare and are not comparable due to different measurement methods. In addition, scarcely has the thermal conductivity in both the fiber direction and transverse direction been studied. The aim of the current research is to show the influence of carbon fiber volume content on the thermal conductivity of laminates. The values are then used to verify the micromechanical models used in the literature. A strong influence on the thermal conductivity could be determined. For the transverse thermal conductivity, the correlation was exponential; for the conductivity in the fiber direction, a linear correlation was found.
Effects of C-Terminal Carboxylation on α-Conotoxin LsIA Interactions with Human α7 Nicotinic Acetylcholine Receptor: Molecular Simulation Studies
Authors: Wen Jierong , Hung Andrew
Published: April 2019

α-Conotoxins selectively bind to nicotinic acetylcholine receptors (nAChRs), which are therapeutic targets due to their important role in signaling transmission in excitable cells. A previous experimental study has demonstrated that carboxylation of the C-terminal of α-conotoxin LsIA reduces its potency to inhibit human α7 nAChR relative to naturally amidated LsIA. However, little is known about the contribution of conformational changes in the receptor and interactions, induced by C-terminal amidation/carboxylation of conotoxins, to selective binding to nAChRs, since most conotoxins and some disulfide-rich peptides from other conotoxin subfamilies possess a naturally amidated C-terminal. In this study, we employ homology modeling and molecular dynamics (MD) simulations to propose the determinants for differential interactions between amidated and carboxylated LsIAs with α7 nAChR. Our findings indicate an overall increased number of contacts favored by binding of amidated LsIA versus its carboxylated counterpart. Toxin-receptor pairwise interactions, which may play a role in enhancing the potency of the former, include ARG10-TRP77, LEU141 and CYS17-GLN79 via persistent hydrogen bonds and cation-π interactions, which are weakened in the carboxylated form due to a strong intramolecular salt-bridge formed by ARG10 and carboxylated C-terminus. The binding of amidated LsIA also induces enhanced movements in loop C and the juxtamembrane Cys-loop that are closely associated with receptor function. Additionally, the impacts of binding of LsIA on the overall structure and inter-subunit contacts were examined using inter-residue network analysis, suggesting a clockwise tilting of the α7 C and F loops upon binding to carboxylated LsIA, which is absent for amidated LsIA binding. The predicted molecular mechanism of LsIA binding to the α7 receptor may provide new insights into the important role of the C-terminal in the binding potency of conotoxins at neuronal nAChRs for pharmacological purposes.
Acquisition and Evaluation of Theoretical Forming Limit Diagram of Al 6061-T6 in Electrohydraulic Forming Process
Authors: Woo Min-A , Song Woo-Jin , Kang Beom-Soo , Kim Jeong
Published: April 2019

The current study examines the forming limit diagram (FLD) of Al 6061-T6 during the electrohydraulic forming process based on the Marciniak–Kuczynski theory (M-K theory). To describe the work-hardening properties of the material, Hollomon’s equation—that includes strain and strain rate hardening parameters—was used. A quasi-static tensile test was performed to obtain the strain-hardening factor and the split-Hopkinson pressure bar (SHPB) test was carried out to acquire the strain rate hardening parameter. To evaluate the reliability of the stress–strain curves obtained from the SHPB test, a numerical model was performed using the LS–DYNA program. Hosford’s yield function was also employed to predict the theoretical FLD. The obtained FLD showed that the material could have improved formability at a high strain rate index condition compared with the quasi-static condition, which means that the high-speed forming process can enhance the formability of sheet metals. Finally, the FLD was compared with the experimental results from electrohydraulic forming (EHF) free-bulging test, which showed that the theoretical FLD was in good agreement with the actual forming limit in the EHF process.
Assessment Wine Aroma Persistence by Using an in Vivo PTR-ToF-MS Approach and Its Relationship with Salivary Parameters
Authors: Muñoz-González Carolina , Canon Francis , Feron Gilles , Guichard Elisabeth , Pozo-Bayón Maria Angeles
Published: April 2019

To better understand wine aroma persistence, the nasal cavity of nine volunteers was monitored by Proton Transfer Reaction-Time of Flight-Mass Spectrometry (PTR-ToF-MS) after they rinsed their mouths with three rosé wines (one control and the same wine supplemented with two tannin extracts) during four minutes. Wines were aromatised with a mixture of five target aroma compounds. Results showed that wine aroma persistence was highly compound-dependent: while esters disappeared very fast, other compounds such as linalool remained in the oral cavity for longer times after wine expectoration. A low effect of tannins (at 50 mg/L) on nasal cavity parameters was observed, with the exception for the compound ethyl decanoate that was significantly higher released in the presence of tannins. Strong interindividual differences on aroma persistence were also found. Significant positive correlations with the salivary total protein content and negative with the salivary flow were observed for specific compounds. This work has studied for the first time in vivo wine aroma persistence in real time from an analytical perspective.
Investigating the Influence of Steric Hindrance on Selective Anion Transport
Authors: Jowett Laura A. , Ricci Angela , Wu Xin , Howe Ethan N. W. , Gale Philip A.
Published: April 2019

A series of symmetrical and unsymmetrical alkyl tren based tris-thiourea anion transporters were synthesised and their anion binding and transport properties studied. Overall, increasing the steric bulk of the substituents resulted in improved chloride binding and transport abilities. Including a macrocycle in the scaffold enhanced the selectivity of chloride transport in the presence of fatty acids, by reducing the undesired H+ flux facilitated by fatty acid flip-flop. This study demonstrates the benefit of including enforced steric hindrance and encapsulation in the design of more selective anion receptors.
Synthesis, In Silico, and In Vitro Evaluation of Anti-Leishmanial Activity of Oxadiazoles and Indolizine Containing Compounds Flagged against Anti-Targets
Authors: Stevanovic Strahinja , Sencanski Milan , Danel Mathieu , Menendez Christophe , Belguedj Roumaissa , Bouraiou Abdelmalek , Nikolic Katarina , Cojean Sandrine , Loiseau Philippe M. , Glisic Sanja , Baltas Michel , García-Sosa Alfonso T.
Published: April 2019

Due to the lack of approved vaccines against human leishmaniasis and the limitations of the current chemotherapy inducing side effects and drug resistance, development of new, effective chemotherapeutic agents is essential. This study describes the synthesis of a series of novel oxadiazoles and indolizine-containing compounds. The compounds were screened in silico using an EIIP/AQVN filter followed by ligand-based virtual screening and molecular docking to parasite arginase. Top hits were further screened versus human arginase and finally against an anti-target battery to tag their possible interactions with proteins essential for the metabolism and clearance of many substances. Eight candidate compounds were selected for further experimental testing. The results show measurable in vitro anti-leishmanial activity for three compounds. One compound with an IC50 value of 2.18 µM on Leishmania donovani intramacrophage amastigotes is clearly better positioned than the others as an interesting molecular template for further development of new anti-leishmanial agents.
In Vivo Gastroprotective and Antidepressant Effects of Iridoids, Verbascoside and Tenuifloroside from Castilleja tenuiflora Benth
Authors: López-Rodríguez Ricardo , Herrera-Ruiz Maribel , Trejo-Tapia Gabriela , Domínguez-Mendoza Blanca Eda , González-Cortazar Manasés , Zamilpa Alejandro
Published: April 2019

Stress is an important factor in the etiology of some illnesses such as gastric ulcers and depression. Castilleja tenuiflora Benth. (Orobanchaceae) is used in Mexican traditional medicine for the treatment of gastrointestinal diseases and nervous disorders. Previous studies indicated that organic extracts from C. tenuiflora had gastroprotective effects and antidepressant activity. In this study, we aimed to evaluate the gastroprotective and antidepressant activity of fractions and isolated compounds from the methanolic extract (MECt) of C. tenuiflora in stressed mice. Chromatographic fractionation of MECt produced four fractions (FCt-1, FCt-2, CFt-3, and FCt-4) as well as four bioactive compounds which were identified using TLC, HPLC and NMR analyses. The cold restraint stress (CRS)-induced gastric ulcer model followed by the tail suspension test and the forced swim test were used to evaluate the gastroprotective effect and antidepressant activity of the extract fractions. FCt-2 and FCt-3 at 100 mg/kg had significant gastroprotective and antidepressant effects. All isolated compounds (verbascoside, teniufloroside and mixture geniposide/ musseanoside) displayed gastroprotective effects and antidepressant activity at 1 or 2 mg/kg. The above results allow us to conclude that these polyphenols and iridoids from C. tenuiflora are responsible for the gastroprotective and antidepressant effects.
The Role of Docosahexaenoic Acid (DHA) on Cognitive Functions in Psychiatric Disorders
Authors: Ciappolino Valentina , Mazzocchi Alessandra , Botturi Andrea , Turolo Stefano , Delvecchio Giuseppe , Agostoni Carlo , Brambilla Paolo
Published: April 2019

Cognitive impairment is strongly associated with functional outcomes in psychiatric patients. Involvement of n-3 long chain polyunsaturated fatty acid (n-3 LC-PUFA), in particular docosahexaenoic acid (DHA), in brain functions is largely documented. DHA is incorporated into membrane phospholipids as structural component, especially in the central nervous system where it also has important functional effects. The aim of this review is to investigate the relationship between DHA and cognitive function in relation to mental disorders. Results from few randomized controlled trials (RCTs) on the effects of DHA (alone or in combination) in psychotic, mood and neurodevelopmental disorders, respectively, suggest that no conclusive remarks can be drawn.
Photoinduced Metal-Free Surface Initiated ATRP from Hollow Spheres Surface
Authors: Yan Chun-Na , Liu Qian , Xu Lin , Bai Li-Ping , Wang Li-Ping , Li Guang
Published: April 2019

Well-defined amphiphilic diblock copolymer poly (methyl methacrylate)-b-poly (N-isopropylacrylamide) grafted hollow spheres (HS-g-PMMA-b-PNIPAM) hybrid materials were synthesized via metal-free surface-initiated atom transfer radical polymerization (SI-ATRP). The ATRP initiators α-Bromoisobutyryl bromide (BIBB) were attached onto hollow sphere surfaces through esterification of acyl bromide groups and hydroxyl groups. The synthetic ATRP initiators (HS-Br) were further used for the metal-free SI-ATRP of methyl methacrylate (MMA) and N-isopropyl acrylamide (NIPAM) using 10-phenylphenothiazine (PTH) as the photocatalyst. The molecular weight of the polymers, structure, morphology, and thermal stability of the hybrid materials were characterized via gel permeation chromatography (GPC), X-ray photoelectron spectroscopy (XPS), 1H-nuclear magnetic resonance spectroscopy (1H NMR), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), and thermogravimetric analysis (TGA), respectively. The results indicated that the ATRP initiator had been immobilized onto HS surfaces successfully followed by metal-free SI-ATRP of MMA and NIPAM, the Br atom had located at the end of the main PMMA polymer chain, and the polymerization process possessed the characteristic of controlled/“living” polymerization. The thermal stability of the hybrid materials was increased significantly compared to the pure PMMA and PNIPAM.
Molecularly Imprinted Polymers for Gossypol via Sol–Gel, Bulk, and Surface Layer Imprinting—A Comparative Study
Authors: Wang Lulu , Zhi Keke , Zhang Yagang , Liu Yanxia , Zhang Letao , Yasin Akram , Lin Qifeng
Published: April 2019

Three gossypol molecularly imprinted polymers (MIPs) were prepared by bulk polymerization (MIP1), surface layer imprinting using silica gel as the support (MIP2), and the sol-gel process (MIP3). The as-prepared MIPs were characterized by SEM and nitrogen adsorption−desorption techniques to study the morphology structure. The adsorption experiments exhibited that MIP1 had adsorption capacity as high as 564 mg·g−1. The MIP2 showed faster adsorption kinetics than MIP1 and MIP3. The adsorption equilibrium could be reached for gossypol in 40 min. A selectivity study showed that the adsorption capacity of MIPs for gossypol was about 1.9 times higher than that of the structurally-similar analogs ellagic acid and 6.6 times higher than that of the quercetin. It was found that the pseudo-second-order kinetic model and the Freundlich isotherm model were more applicable for the adsorption kinetics and adsorption isotherm of gossypol binding onto the MIP1 and MIP2, respectively. Results suggested that among those three, the MIP2 was a desirable sorbent for rapid adsorption and MIP1 was suitable for selective recognition of gossypol.
Impact of Thermal Radiation and Heat Source/Sink on MHD Time-Dependent Thin-Film Flow of Oldroyed-B, Maxwell, and Jeffry Fluids over a Stretching Surface
Authors: Khan Abdul Samad , Nie Yufeng , Shah Zahir
Published: April 2019

In this study paper, we examined the magnetohydrodynamic (MHD) flow of three combined fluids, Maxwell, Jeffry, and Oldroyed- B fluids, with variable heat transmission under the influence of thermal radiation embedded in a permeable medium over a time-dependent stretching sheet. The fluid flow of liquid films was assumed in two dimensions. The fundamental leading equations were changed to a set of differential nonlinear and coupled equations. For this conversion, suitable similarity variables were used. An optimal tactic was used to acquire the solution of the modeled problems. The convergence of the technique has been shown numerically. The obtained analytical and numerical consequences are associated graphically and tabulated. An excellent agreement was obtained between the homotropy analysis method (HAM) and numerical methods. The variation of the skin friction and Nusslet number and their influence on the temperature and concentration profiles were scrutinized. The influence of the thermal radiation, unsteadiness effect, and MHD were the main focus of this study. Furthermore, for conception to be physically demonstrated, the entrenched parameters are discussed graphically in detail along with their effect on liquid film flow.
Study of Industrial Naphtha Catalytic Reforming Reactions via Modelling and Simulation
Authors: Yusuf Aminu Zakari , Aderemi B. O. , Patel Raj , Mujtaba Iqbal M.
Published: April 2019

Steady state and dynamic modelling and simulation of catalytic reforming unit of Kaduna Refining & Petrochemical Company, NNPC (Nigeria) was carried to find out the behaviour of the reactions under both steady and unsteady state conditions. The basic model together with kinetic and thermodynamic parameters and properties were taken from the literature but is developed in gPROMs (an equation oriented modelling software) model building platform for the first time rather than in MATLAB or other modelling platform used by other researchers in the past. The simulation was performed using gPROMs and the predictions were validated against those available in the literature. The validated model was then used to monitor the behaviour of the temperature, concentrations of paraffins, naphthenes and aromatics with respect to both time and height of the reactor of the industrial refinery of Nigeria. Hydrogen yield, Research octane number (RON) and temperature profiles are also reported. The components behave similarly in terms of reactions in the reactors but the time to attain quasi-steady state is different. The results are in good agreement with the industrial plant data.