bluuebunny/crossref_metadata_2025 huggingface dataset:
Beyond Covalent Crosslinks: Applications of Supramolecular Gels
Authors: Christoff-Tempesta Ty , Lew Andrew J. , Ortony Julia H.
Published: May 2018

Traditionally, gels have been defined by their covalently cross-linked polymer networks. Supramolecular gels challenge this framework by relying on non-covalent interactions for self-organization into hierarchical structures. This class of materials offers a variety of novel and exciting potential applications. This review draws together recent advances in supramolecular gels with an emphasis on their proposed uses as optoelectronic, energy, biomedical, and biological materials. Additional special topics reviewed include environmental remediation, participation in synthesis procedures, and other industrial uses. The examples presented here demonstrate unique benefits of supramolecular gels, including tunability, processability, and self-healing capability, enabling a new approach to solve engineering challenges.
Emergence of Wrinkles during the Curing of Coatings
Authors: Shimokawa Michiko , Yoshida Hikaru , Komatsu Takumi , Omachi Rena , Kudo Kazue
Published: May 2018

Wrinkles often emerge on a paint layer when a second coat of paint is applied on an already-coated substrate. Wrinkle formation occurs when the first layer absorbs organic solvent from the second layer. We set up experiments to mimic the double-coating process, focusing on the interaction between a paint layer and an organic solvent. In the experiments, we investigated the characteristic wavelengths of the wrinkles and the time of wrinkle emergence. We employed a simple model to explain the wrinkle emergence and performed numerical simulations. The linear stability analysis of the model provides a relation between the wavelengths and the characteristic timescale that agrees reasonably well with our experimental data as well as numerical results. Our results indicate that compression of the layer due to swelling and delamination are both important factors in the formation of wrinkles.
The Colorful Sex Chromosomes of Teleost Fish
Authors: Kottler Verena A. , Schartl Manfred
Published: May 2018

Teleost fish provide some of the most intriguing examples of sexually dimorphic coloration, which is often advantageous for only one of the sexes. Mapping studies demonstrated that the genetic loci underlying such color patterns are frequently in tight linkage to the sex-determining locus of a species, ensuring sex-specific expression of the corresponding trait. Several genes affecting color synthesis and pigment cell development have been previously described, but the color loci on the sex chromosomes have mostly remained elusive as yet. Here, we summarize the current knowledge about the genetics of such color loci in teleosts, mainly from studies on poeciliids and cichlids. Further studies on these color loci will certainly provide important insights into the evolution of sex chromosomes.
The Most Important Virulence Markers of Yersinia enterocolitica and Their Role during Infection
Authors: Bancerz-Kisiel Agata , Pieczywek Marta , Łada Piotr , Szweda Wojciech
Published: May 2018

Yersinia enterocolitica is the causative agent of yersiniosis, a zoonotic disease of growing epidemiological importance with significant consequences for public health. This pathogenic species has been intensively studied for many years. Six biotypes (1A, 1B, 2, 3, 4, 5) and more than 70 serotypes of Y. enterocolitica have been identified to date. The biotypes of Y. enterocolitica are divided according to their pathogenic properties: the non-pathogenic biotype 1A, weakly pathogenic biotypes 2–5, and the highly pathogenic biotype 1B. Due to the complex pathogenesis of yersiniosis, further research is needed to expand our knowledge of the molecular mechanisms involved in the infection process and the clinical course of the disease. Many factors, both plasmid and chromosomal, significantly influence these processes. The aim of this study was to present the most important virulence markers of Y. enterocolitica and their role during infection.
Shared and Species-Specific Patterns of Nascent Y Chromosome Evolution in Two Guppy Species
Authors: Morris Jake , Darolti Iulia , Bloch Natasha I. , Wright Alison E. , Mank Judith E.
Published: May 2018

Sex chromosomes form once recombination is halted around the sex-determining locus between a homologous pair of chromosomes, resulting in a male-limited Y chromosome. We recently characterized the nascent sex chromosome system in the Trinidadian guppy (Poecilia reticulata). The guppy Y is one of the youngest animal sex chromosomes yet identified, and therefore offers a unique window into the early evolutionary forces shaping sex chromosome formation, particularly the rate of accumulation of repetitive elements and Y-specific sequence. We used comparisons between male and female genomes in P. reticulata and its sister species, Endler’s guppy (P. wingei), which share an ancestral sex chromosome, to identify male-specific sequences and to characterize the degree of differentiation between the X and Y chromosomes. We identified male-specific sequence shared between P. reticulata and P. wingei consistent with a small ancestral non-recombining region. Our assembly of this Y-specific sequence shows substantial homology to the X chromosome, and appears to be significantly enriched for genes implicated in pigmentation. We also found two plausible candidates that may be involved in sex determination. Furthermore, we found that the P. wingei Y chromosome exhibits a greater signature of repetitive element accumulation than the P. reticulata Y chromosome. This suggests that Y chromosome divergence does not necessarily correlate with the time since recombination suppression. Overall, our results reveal the early stages of Y chromosome divergence in the guppy.
Did Lizards Follow Unique Pathways in Sex Chromosome Evolution?
Authors: Alam Shayer Mahmood Ibney , Sarre Stephen D. , Gleeson Dianne , Georges Arthur , Ezaz Tariq
Published: May 2018

Reptiles show remarkable diversity in modes of reproduction and sex determination, including high variation in the morphology of sex chromosomes, ranging from homomorphic to highly heteromorphic. Additionally, the co-existence of genotypic sex determination (GSD) and temperature-dependent sex determination (TSD) within and among sister clades makes this group an attractive model to study and understand the evolution of sex chromosomes. This is particularly so with Lizards (Order Squamata) which, among reptiles, show extraordinary morphological diversity. They also show no particular pattern of sex chromosome degeneration of the kind observed in mammals, birds and or even in snakes. We therefore speculate that sex determination sensu sex chromosome evolution is labile and rapid and largely follows independent trajectories within lizards. Here, we review the current knowledge on the evolution of sex chromosomes in lizards and discuss how sex chromosome evolution within that group differs from other amniote taxa, facilitating unique evolutionary pathways.
Whole Exome Sequencing Identifies New Host Genomic Susceptibility Factors in Empyema Caused by Streptococcus pneumoniae in Children: A Pilot Study
Authors: Salas Antonio , Pardo-Seco Jacobo , Barral-Arca Ruth , Cebey-López Miriam , Gómez-Carballa Alberto , Rivero-Calle Irene , Pischedda Sara , Currás-Tuala María-José , Amigo Jorge , Gómez-Rial José , Martinón-Torres Federico ,   On behalf of GENDRES Network
Published: May 2018

Pneumonia is the leading cause of death amongst infectious diseases. Streptococcus pneumoniae is responsible for about 25% of pneumonia cases worldwide, and it is a major cause of childhood mortality. We carried out a whole exome sequencing (WES) study in eight patients with complicated cases of pneumococcal pneumonia (empyema). An initial assessment of statistical association of WES variation with pneumonia was carried out using data from the 1000 Genomes Project (1000G) for the Iberian Peninsula (IBS) as reference controls. Pseudo-replication statistical analyses were carried out using different European control groups. Association tests pointed to single nucleotide polymorphism (SNP) rs201967957 (gene MEIS1; chromosome 2; p-valueIBS = 3.71 × 10−13) and rs576099063 (gene TSPAN15; chromosome 10; p-valueIBS = 2.36 × 10−8) as the best candidate variants associated to pneumococcal pneumonia. A burden gene test of pathogenicity signaled four genes, namely, OR9G9, MUC6, MUC3A and APOB, which carry significantly increased pathogenic variation when compared to controls. By analyzing various transcriptomic data repositories, we found strong supportive evidence for the role of MEIS1, TSPAN15 and APOBR (encoding the receptor of the APOB protein) in pneumonia in mouse and human models. Furthermore, the association of the olfactory receptor gene OR9G9 has recently been related to some viral infectious diseases, while the role of mucin genes (MUC6 and MUC3A), encoding mucin glycoproteins, are well-known factors related to chronic obstructive airway disease. WES emerges as a promising technique to disentangle the genetic basis of host genome susceptibility to infectious respiratory diseases.
Telomere Maintenance Mechanisms in Cancer
Authors: Gaspar Tiago Bordeira , Sá Ana , Lopes José Manuel , Sobrinho-Simões Manuel , Soares Paula , Vinagre João
Published: May 2018

Tumour cells can adopt telomere maintenance mechanisms (TMMs) to avoid telomere shortening, an inevitable process due to successive cell divisions. In most tumour cells, telomere length (TL) is maintained by reactivation of telomerase, while a small part acquires immortality through the telomerase-independent alternative lengthening of telomeres (ALT) mechanism. In the last years, a great amount of data was generated, and different TMMs were reported and explained in detail, benefiting from genome-scale studies of major importance. In this review, we address seven different TMMs in tumour cells: mutations of the TERT promoter (TERTp), amplification of the genes TERT and TERC, polymorphic variants of the TERT gene and of its promoter, rearrangements of the TERT gene, epigenetic changes, ALT, and non-defined TMM (NDTMM). We gathered information from over fifty thousand patients reported in 288 papers in the last years. This wide data collection enabled us to portray, by organ/system and histotypes, the prevalence of TERTp mutations, TERT and TERC amplifications, and ALT in human tumours. Based on this information, we discuss the putative future clinical impact of the aforementioned mechanisms on the malignant transformation process in different setups, and provide insights for screening, prognosis, and patient management stratification.
Virtual Crop Water Export Analysis: The Case of Greece at River Basin District Level
Authors: Mellios Nikolaos , Koopman Jason , Laspidou Chrysi
Published: May 2018

An analysis of virtual crop water export through international trade is conducted for Greece, downscaled to the River Basin District (RBD) level, in order to identify critical “hotspots” of localized water shortage in the country. A computable general equilibrium model (MAGNET) was used to obtain the export shares of crops and associated irrigation water was calculated for all major crops in Greece. A distinction between virtual crop water locally consumed and traded internationally was made for all Greek RBDs. Cotton was identified as a large water consumer and virtual water exporter, while GR08 and GR10 were identified as the RBDs mostly impacted. The value of virtual water exported was calculated for all crop types and fruits and vegetables were identified as the crop most beneficial, since they consume the least water for the obtained value.
Young-Adult Polycystic Kidney Disease is Associated with Major Cardiovascular Complications
Authors: Chuang Ya-Wen , Yu Tung-Min , Huang Shih-Ting , Sun Kuo-Ting , Lo Ying-Chih , Fu Pin-Kuei , Lee Bor-Jen , Chen Cheng-Hsu , Lin Cheng-Li , Kao Chia-Hung
Published: May 2018

Background: Patients with polycystic kidney disease (PKD) might have a risk of cardiovascular diseases because several cardiovascular risk factors are occasionally associated with PKD patients. Data on the association between PKD and the risk of cardiovascular events, including acute coronary syndrome (ACS), stroke, and congestive heart failure (CHF), are scant. Methods: Patients aged ≥20 years who were newly diagnosed with PKD (International Classification of Diseases, Ninth Revision, Clinical Modification codes 753.12 and 753.13) between 2000 and 2011 were selected as a PKD cohort (N = 5157). The association between PKD and cardiovascular events was analyzed. Results: We randomly selected a comparison cohort of people without PKD, who were frequency-matched by sex, age, and index date of diagnosis. At the end of 2011, the PKD cohort had a 1.40-fold greater incidence of ACS compared with the comparison cohort (8.59 vs. 6.17 per 1000 person-years), in addition to a 1.40-fold greater incidence of stroke, a 1.49-fold greater incidence of CHF, and a 1.64-fold greater incidence of mortality. Conclusions: This retrospective cohort study shows that patients with PKD have an increased risk of cardiovascular events including ACS, stroke, and CHF as well as mortality, particularly in younger patients. Early identification is necessary to attenuate the risk of cardiovascular complications in patients with PKD.
The Relationship between Diabetes Mellitus and Respiratory Function in Patients Eligible for Coronary Artery Bypass Grafting
Authors: Szylińska Aleksandra , Listewnik Mariusz , Ciosek Żaneta , Ptak Magdalena , Mikołajczyk Anna , Pawlukowska Wioletta , Rotter Iwona
Published: May 2018

Introduction: Spirometry performed prior to surgery provides information on the types of lung disorders in patients. The purpose of this study was to look for a relationship between the prevalence of diabetes and spirometry parameters. Material and Methods: The study was conducted in patients with coronary artery disease who were eligible for an isolated coronary artery bypass graft in 2013. The study group included 367 patients (287 men and 80 women) aged 68.7 ± 8.4 years. They were divided into those with diagnosed diabetes (group I, n = 138, 37.6%) and without diabetes (group II, n = 229, 62.4%). Spirometry tests were performed on the day of admission to the hospital. Results: Patients with diabetes (group I) had a significantly higher body mass index than those without diabetes (group II). Spirometry tests also showed that patients with diabetes had statistically significantly lower forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1.0). Both FVC and FEV1.0 were also statistically significantly lower for overweight and obese individuals in group I than those in group II. Conclusion: Patients with diabetes eligible for coronary artery bypass grafting with concurrent overweight or obesity are more likely to have lower spirometry parameters than those without diabetes.
A Multivariate Approach to Study Drivers of Land-Cover Changes through Remote Sensing in the Dry Chaco of Argentina
Authors: Hoyos Laura E. , Cabido Marcelo R. , Cingolani Ana M.
Published: May 2018

Land-cover changes are driven by different combinations of biophysical, economic, and cultural drivers that are acting at different scales. We aimed to (1) analyze trends in land use and land cover changes (conversion, abandonment, forest persistence) in the dry Chaco in central Argentina (1979 to 2010), and (2) examine how physical and socio-economic drivers have influenced those changes. Based on Landsat data, we obtained the proportion of 16 classes of land cover changes for 81 individual circular samples. We performed a Principal Component Analysis (PCA) to identify the main trends of change across the whole region. To explore the relationships between the changes in land cover and drivers, we developed a GIS comprising thematic maps representing the different drivers. The drivers were first correlated with the two first PCA axes, and in a second approximation were subjected to multiple regression analyses. We obtained in this way the best model to explain each PCA axis. The highest conversion, as indicated by PCA axis 1, was experienced by flat areas close to roads and with the highest annual rainfall. Besides agricultural expansion that was triggered by precipitation increase as a major driver of forest conversion, changes that were observed during the period 1979–2010, may have also been influenced by several other driving forces acting at different spatial scales and contexts.
The Use and Safety of TNF Inhibitors during Pregnancy in Women with Psoriasis: A Review
Authors: Johansen Cæcilie Bachdal , Jimenez-Solem Espen , Haerskjold Ann , Sand Freja Lærke , Thomsen Simon Francis
Published: May 2018

Psoriasis is a chronic immune-mediated inflammatory disease affecting women of childbearing potential. Biologic agents, notably Tumor Necrosis Factor inhibitors (TNFi), are the only current non-contraindicated systemic treatment option during pregnancy. TNFi comprised of complete immunoglobulin G (IgG) antibodies antibodies (adalimumab, golimumab, and infliximab) actively cross the placenta from the second trimester and are detectable in the child up to one year postpartum. Data on safety of TNFi are conflicting; however a trend towards drug-specific harm has been reported, with increased risk of congenital malformations and preterm birth. TNFi exposure may alter the immune system of the infant towards hypersensitivity and reduced response to intracellular infections. Confounding by indication should be considered, as chronic inflammatory disease itself may pose a risk of adverse pregnancy outcomes. The quality of the current evidence is very low and no studies specifically address TNFi safety in women with psoriasis. Nonetheless, risks associated with TNFi treatment must be balanced against the as-yet uncertain risk of adverse outcomes in infants born to women with severe psoriasis. We searched PubMed using Medical Subject Headings (MeSH) terms and identified relevant studies and guidelines. Herein, we present the current knowledge of the use and safety of TNFi during pregnancy in women with psoriasis.
MCPIP3 as a Potential Metastasis Suppressor Gene in Human Colorectal Cancer
Authors: Suk Fat-Moon , Chang Chi-Ching , Lin Ren-Jye , Lin Shyr-Yi , Chen Ya-Ting , Liang Yu-Chih
Published: May 2018

Monocyte chemotactic protein induced protein 3 (MCPIP3) belongs to the Cys–Cys–Cys–His (CCCH)-zinc finger protein family and contains a highly conserved CCCH-zinc finger domain and a Nedd4-BP1 YacP nuclease (NYN) domain. Previous studies showed that MCPIP3 inhibits the expression of proinflammatory genes, such as vascular cell adhesion molecule (VCAM)-1, in human endothelial cells, but the roles and functions of MCPIP3 in cancer cells are still unknown. In human colorectal cancer specimens, we found that the messenger RNA expression of MCPIP3 was significantly downregulated in cancer tissues compared to adjacent normal tissues (18/25; average fold change of 8.18). Two cell models were used to demonstrate the anti-migration activity of MCPIP3. First, Tet-on T-REx-293/HA-MCPIP3 cells were used to examine whether MCPIP3 can change epithelial–mesenchymal transition (EMT)-related gene expressions. Second, we used two human colorectal cancer cell lines, SW620 and HCT116, to prove the role of MCPIP3 in regulating EMT-related gene expressions. We found that overexpression of MCPIP3 inhibited cell migration according to a wound-healing assay and Transwell invasion assay and vimentin expression, and increased E-cadherin expression in these two cell lines. These results suggest that MCPIP3 might play a negative role in cell migration of human colorectal cancer cells.
Phosphatidylcholine Membrane Fusion Is pH-Dependent
Authors: Akimov Sergey , Polynkin Michael A. , Jiménez-Munguía Irene , Pavlov Konstantin V. , Batishchev Oleg V.
Published: May 2018

Membrane fusion mediates multiple vital processes in cell life. Specialized proteins mediate the fusion process, and a substantial part of their energy is used for topological rearrangement of the membrane lipid matrix. Therefore, the elastic parameters of lipid bilayers are of crucial importance for fusion processes and for determination of the energy barriers that have to be crossed for the process to take place. In the case of fusion of enveloped viruses (e.g., influenza) with endosomal membrane, the interacting membranes are in an acidic environment, which can affect the membrane’s mechanical properties. This factor is often neglected in the analysis of virus-induced membrane fusion. In the present work, we demonstrate that even for membranes composed of zwitterionic lipids, changes of the environmental pH in the physiologically relevant range of 4.0 to 7.5 can affect the rate of the membrane fusion notably. Using a continual model, we demonstrated that the key factor defining the height of the energy barrier is the spontaneous curvature of the lipid monolayer. Changes of this parameter are likely to be caused by rearrangements of the polar part of lipid molecules in response to changes of the pH of the aqueous solution bathing the membrane.
A Worst Case Performance Analysis of Approximated Zero Forcing Vectoring for DSL Systems
Authors: Mazzenga Franco , Giuliano Romeo
Published: May 2018

In this paper we introduce a Gaussian approximation for the achievable downstream bit rate per user in modern broadband and ultra-broadband digital subscriber loop-based access systems. The considered formulation allows one to account for the main characteristics of the interference scenario (e.g., number and positions of interferers along the cable), the far-end crosstalk (FEXT) fluctuations, bit loading limitation per sub-carrier, and approximated zero forcing in vectoring pre-coding. Formulas are obtained assuming log-normal statistics for the signal-to-interference plus noise ratio per sub-carrier. The validity of the considered approximation has been assessed by computer calculation. A very good agreement between the exact and the approximated bit rates is obtained. The bit rate approximation is then used to analyze the performance of a very high-speed digital subscriber line type 2 (VDSL2, Profile 35b) with vectoring and used to assess G.fast performance degradation when approximated zero forcing in vectoring pre-coding is applied. It is observed for G.fast performance that degradation due to residual FEXT after vectoring pre-coding can be relevant. A significant performance improvement can be achieved at the expense of increased computational complexity of the vectoring pre-coding.
Ontology-Based Domain Analysis for Model Driven Pervasive Game Development
Authors: Guo Hong , Gao Shang , Trætteberg Hallvard , Wang Alf Inge , Jaccheri Letizia
Published: May 2018

Domain Analysis (DA) plays an important role in Model Driven Development (MDD) and Domain-Specific Modeling (DSM). However, most formal DA methods are heavy weight and not practical sometimes. For instance, when computer games are developed, the problem domain (game design) is decided gradually within numerous iterations. It is not practical to fit a heavy-weight DA in such an agile process. In this research, we propose a light-weight DA which can be embedded in the original game development process. The DA process is based on a game ontology which serves for both game design and domain analysis. In this paper, we introduce the ontology and demonstrate how to use it in the domain analysis process. We discuss the quality and evaluate the ontology with a user acceptance survey. The test result shows that most potential users considered the ontology useful and easy to use.
Social Engineering Attacks and Countermeasures in the New Zealand Banking System: Advancing a User-Reflective Mitigation Model
Authors: Airehrour David , Vasudevan Nair Nisha , Madanian Samaneh
Published: May 2018

Social engineering attacks are possibly one of the most dangerous forms of security and privacy attacks since they are technically oriented to psychological manipulation and have been growing in frequency with no end in sight. This research study assessed the major aspects and underlying concepts of social engineering attacks and their influence in the New Zealand banking sector. The study further identified attack stages and provided a user-reflective model for the mitigation of attacks at every stage of the social engineering attack cycle. The outcome of this research was a model that provides users with a process of having a reflective stance while engaging in online activities. Our model is proposed to aid users and, of course, financial institutions to re-think their anti-social engineering strategies while constantly maintaining a self-reflective assessment of whether they are being subjected to social engineering attacks while transacting online.
An Internet of Things Based Multi-Level Privacy-Preserving Access Control for Smart Living
Authors: Salama Usama , Yao Lina , Paik Hye-young
Published: May 2018

The presence of the Internet of Things (IoT) in healthcare through the use of mobile medical applications and wearable devices allows patients to capture their healthcare data and enables healthcare professionals to be up-to-date with a patient’s status. Ambient Assisted Living (AAL), which is considered as one of the major applications of IoT, is a home environment augmented with embedded ambient sensors to help improve an individual’s quality of life. This domain faces major challenges in providing safety and security when accessing sensitive health data. This paper presents an access control framework for AAL which considers multi-level access and privacy preservation. We focus on two major points: (1) how to use the data collected from ambient sensors and biometric sensors to perform the high-level task of activity recognition; and (2) how to secure the collected private healthcare data via effective access control. We achieve multi-level access control by extending Public Key Infrastructure (PKI) for secure authentication and utilizing Attribute-Based Access Control (ABAC) for authorization. The proposed access control system regulates access to healthcare data by defining policy attributes over healthcare professional groups and data classes classifications. We provide guidelines to classify the data classes and healthcare professional groups and describe security policies to control access to the data classes.
Atomic Layer Deposition of Lithium Fluoride Optical Coatings for the Ultraviolet
Authors: Hennessy John , Nikzad Shouleh
Published: May 2018

Lithium fluoride is an important material for ultraviolet optical systems, possessing among the largest optical bandgaps of dielectric materials. We report on the development of an atomic layer deposition (ALD) process for lithium fluoride that is capable of depositing thin films in a self-limiting manner, with an approximate deposition rate of approximately 0.15 Å per ALD cycle at a substrate temperature of 150 °C. Films are characterized by spectroscopic ellipsometry, atomic force microscopy, X-ray photoelectron spectroscopy, and far ultraviolet reflectometry. For substrate temperatures of 150 °C and greater, films showed significant microroughness with a correlated reduction in effective refractive index. This behavior was mitigated by a reduction in substrate temperature to as low as 100 °C. Films deposited on silicon substrates were subjected to long-term storage testing to evaluate the environmental sensitivity of the deposited layers. Protected aluminum mirrors were also fabricated with ALD LiF overcoats, yielding a reflectance of 84% at a wavelength of 125 nm. The performance relative to state-of-the-art LiF thin films deposited by physical vapor deposition methods is discussed, along with the prospects for future optimization.
The Role of Mucin in the Toxicological Impact of Polystyrene Nanoparticles
Authors: Inkielewicz-Stepniak Iwona , Tajber Lidia , Behan Gavin , Zhang Hongzhou , Radomski Marek W. , Medina Carlos , Santos-Martinez Maria J.
Published: May 2018

The development of novel oral drug delivery systems is an expanding area of research and both new approaches for improving their efficacy and the investigation of their potential toxicological effect are crucial and should be performed in parallel. Polystyrene nanoparticles (NPs) have been used for the production of diagnostic and therapeutic nanosystems, are widely used in food packaging, and have also served as models for investigating NPs interactions with biological systems. The mucous gel layer that covers the epithelium of the gastrointestinal system is a complex barrier-exchange system that it is mainly constituted by mucin and it constitutes the first physical barrier encountered after ingestion. In this study, we aimed to investigate the effect of polystyrene NPs on mucin and its potential role during NP–cell interactions. For this purpose, we evaluated the interaction of polystyrene NPs with mucin in dispersion by dynamic light scattering and with a deposited layer of mucin using a quartz crystal microbalance with dissipation technology. Next, we measured cell viability and the apoptotic state of three enterocyte-like cell lines that differ in their ability to produce mucin, after their exposure to the NPs. Positive charged NPs showed the ability to strongly interact and aggregate mucin in our model. Positive NPs affected cell viability and induced apoptosis in all cell lines independently of their ability of produce mucin.
Facile Fabrication of a PDMS@Stearic Acid-Kaolin Coating on Lignocellulose Composites with Superhydrophobicity and Flame Retardancy
Authors: Wang Zhe , Shen Xiaoping , Qian Temeng , Wang Junjie , Sun Qingfeng , Jin Chunde
Published: May 2018

The disadvantages such as swelling after absorbing water and flammability restrict the widespread applications of lignocellulose composites (LC). Herein, a facile and effective method to fabricate superhydrophobic surfaces with flame retardancy on LC has been investigated by coating polydimethylsiloxane (PDMS) and stearic acid (STA) modified kaolin (KL) particles. The as-prepared coatings on the LC exhibited a good repellency to water (a contact angle = 156°). Owing to the excellent flame retardancy of kaolin particles, the LC coated with PDMS@STA-KL displayed a good flame retardancy during limiting oxygen index and cone calorimeter tests. After the coating treatment, the limiting oxygen index value of the LC increased to 41.0. Cone calorimetry results indicated that the ignition time of the LC coated with PDMS@STA-KL increased by 40 s compared with that of uncoated LC. Moreover, the peak heat release rate (PHRR) and the total heat release (THR) of LC coated with PDMS@STA-KL reduced by 18.7% and 19.2% compared with those of uncoated LC, respectively. This LC coating with improved water repellency and flame retardancy can be considered as a potential alternative to protect the lignocellulose composite.
Two-Level Finite Element Approximation for Oseen Viscoelastic Fluid Flow
Authors: Nasu Nasrin Jahan , Mahbub Md. Abdullah Al , Hussain Shahid , Zheng Haibiao
Published: May 2018

In this paper, a two-level finite element method for Oseen viscoelastic fluid flow obeying an Oldroyd-B type constitutive law is presented. With the newly proposed algorithm, solving a large system of the constitutive equations will not be much more complex than the solution of one linearized equation. The viscoelastic fluid flow constitutive equation consists of nonlinear terms, which are linearized by taking a known velocity b ( x ) , and transforms into the Oseen viscoelastic fluid flow model. Since Oseen viscoelastic fluid flow is already linear, we use a two-level method with a new technique. The two-level approach is consistent and efficient to study the coupled system which contains nonlinear terms. In the first step, the solution on the coarse grid is derived, and the result is used to determine the solution on the fine mesh in the second step. The decoupling algorithm takes two steps to solve a linear system on the fine mesh. The stability of the algorithm is derived for the temporal discretization and obtains the desired error bound. Two numerical experiments are executed to show the accuracy of the theoretical analysis. The approximations of the stress tensor, velocity vector, and pressure field are P 1 -discontinuous, P 2 -continuous and P 1 -continuous finite elements respectively.
Single-Molecule Tethered Particle Motion: Stepwise Analyses of Site-Specific DNA Recombination
Authors: Fan Hsiu-Fang , Ma Chien-Hui , Jayaram Makkuni
Published: May 2018

Tethered particle motion/microscopy (TPM) is a biophysical tool used to analyze changes in the effective length of a polymer, tethered at one end, under changing conditions. The tether length is measured indirectly by recording the Brownian motion amplitude of a bead attached to the other end. In the biological realm, DNA, whose interactions with proteins are often accompanied by apparent or real changes in length, has almost exclusively been the subject of TPM studies. TPM has been employed to study DNA bending, looping and wrapping, DNA compaction, high-order DNA–protein assembly, and protein translocation along DNA. Our TPM analyses have focused on tyrosine and serine site-specific recombinases. Their pre-chemical interactions with DNA cause reversible changes in DNA length, detectable by TPM. The chemical steps of recombination, depending on the substrate and the type of recombinase, may result in a permanent length change. Single molecule TPM time traces provide thermodynamic and kinetic information on each step of the recombination pathway. They reveal how mechanistically related recombinases may differ in their early commitment to recombination, reversibility of individual steps, and in the rate-limiting step of the reaction. They shed light on the pre-chemical roles of catalytic residues, and on the mechanisms by which accessory proteins regulate recombination directionality.
Trace Element and U–Pb Core Age for Zircons from Western Meiganga Gold Placer, Cameroon: Their Genesis and Archean-Proterozoic Sources
Authors: Kanouo Nguo Sylvestre , Ngueutchoua Gabriel , Kouske Arnaud Patrice , Yongue Rose Fouateu , Venkatesh Akella Satya
Published: May 2018

Trace element concentrations and U–Pb ages were obtained using Laser Ablation Split Stream Method from the core of 115 zircon grains from the western Meiganga gold placer deposit. The data was used to characterize zircon, to understand the history of crystallization and to locate source rocks within the local and regional geological settings. Zircon trace element geochemistry was used to distinguish between magmatic and metamorphic affinity. The magmatic zircons have characteristics compatible with their probable origin from granitoid, syenite, tonalite, charnockite and mafic to ultramafic rocks. The metamorphic zircons composition is compatible with growth from anatectic melts and by sub-solidus crystallization in equilibrium with garnet. The zircon ages reveal Archean, Paleoproterozoic, Mesoproterozic, and Neoproterozoic events with the principal source could mainly belong to Paleoproterozoic magmatic lineage. Some of the Paleoproterozoic magmatic zircons were probably sourced from two mica granite found within the local geology, whereas the remaining zircons have features indicating source rocks within the Congo Craton. We suggest that the geologic history of these zircons is related to crustal-scale magmatic and/or tectono-metamorphic events, possibly linked to Eburnean and Pan-African orogeny.
Three New Highly Oxygenated Germacranolides from Carpesium Divaricatum and Their Cytotoxic Activity
Authors: Zhang Tao , Si Jin-Guang , Zhang Qiu-Bo , Chen Jia-Huan , Ding Gang , Zhang Hong-Wu , Jia Hong-Mei , Zou Zhong-Mei
Published: May 2018

Three new highly oxygenated (2–4), and two known (1 and 5) germacranolides, were isolated from the whole plant of Carpesium divaricatum. The planar structures and relative configurations of the new compounds were determined by detailed spectroscopic analysis. The absolute configuration of 1 was established using the circular dichroism (CD) method and X-ray diffraction, and the stereochemistry of the new compounds 2–4 were determined using similar CD spectra with 1. The new compound 2 and the known compound 5 exhibited potent cytotoxicity against hepatocellular cancer (Hep G2) and human cervical cancer (HeLa) cells, superior to those of the positive control cis-platin.
Simulation and Feedback in Health Education: A Mixed Methods Study Comparing Three Simulation Modalities
Authors: Tait Lauren , Lee Kenneth , Rasiah Rohan , Cooper Joyce M. , Ling Tristan , Geelan Benjamin , Bindoff Ivan
Published: May 2018

Background. There are numerous approaches to simulating a patient encounter in pharmacy education. However, little direct comparison between these approaches has been undertaken. Our objective was to investigate student experiences, satisfaction, and feedback preferences between three scenario simulation modalities (paper-, actor-, and computer-based). Methods. We conducted a mixed methods study with randomized cross-over of simulation modalities on final-year Australian graduate-entry Master of Pharmacy students. Participants completed case-based scenarios within each of three simulation modalities, with feedback provided at the completion of each scenario in a format corresponding to each simulation modality. A post-simulation questionnaire collected qualitative and quantitative responses pertaining to participant satisfaction, experiences, and feedback preferences. Results. Participants reported similar levels satisfaction across all three modalities. However, each modality resulted in unique positive and negative experiences, such as student disengagement with paper-based scenarios. Conclusion. Importantly, the themes of guidance and opportunity for peer discussion underlie the best forms of feedback for students. The provision of feedback following simulation should be carefully considered and delivered, with all three simulation modalities producing both positive and negative experiences in regard to their feedback format.
Controlled Levofloxacin Release and Antibacterial Properties of β-Cyclodextrins-Grafted Polypropylene Mesh Devices for Hernia Repair
Authors: Sanbhal Noor , Saitaer Xiakeer , Li Yan , Mao Ying , Zou Ting , Sun Gang , Wang Lu
Published: May 2018

Mesh infection is a major complication of hernia repair. After knitted mesh implantation, bacteria can grow within textile structures causing infection. In this work, polypropylene (PP) mesh devices were two-step grafted with hexamethylene diisocyanate (HDI) and β–cyclodexrins (CD) and then loaded with suitable antimicrobial levofloxacin HCL for hernia mesh-infection prevention. First, oxygen plasma was able to create surface roughness, then HDI was successfully grafted onto PP fiber surfaces. Afterwards, CD was covalently grafted onto the HDI treated PP meshes, and levofloxacin HCL (LVFX) was loaded into the CD cavity of the modified meshes. The modified devices were evaluated for sustained antibiotic properties and drug-release profiles in a phosphate buffer, and sustained drug release was observed between interfaces of meshes and aqueous environment. The antibiotic-loaded PP mesh samples demonstrated sustained antibacterial properties for 7 and 10 days, respectively, against both Gram-negative and Gram-positive bacteria. The CD-captured levofloxacin HCL showed burst release after 6 h but later exhibited sustained release for the next 48 h. Among all samples, the modified mesh LVFX-6 was more stable and showed more sustained drug release and could be employed in future clinical applications.
Transformation of H-Aggregates and J-Dimers of Water-Soluble Tetrakis (4-carboxyphenyl) Porphyrin in Polyion Complex Micelles
Authors: Liu Shuai , Hu Cun , Wei Ying , Duan Ming , Chen Xin , Hu Yue
Published: May 2018

Tetrakis (4-carboxyphenyl) porphyrin (TCPP) and polyelectrolyte poly(N-methyl-2-vinylpyridinium iodide)-b-poly(ethylene oxide) (PMVP41-b-PEO205) can self-aggregate into polyion complex (PIC) micelles in alkaline aqueous solution. UV-vis spectroscopy, fluorescence spectroscopy, transmission electron microscope, and dynamic light scattering were carried out to study PIC micelles. Density functional theory (DFT) calculation method was applied to study the interaction of TCPP and PMVP41-b-PEO205. We found that the H-aggregates and J-dimers of anionic TCPP transformed in PIC micelles. H-aggregates of TCPP formed at the charge ratio of TCPP/PMVP41-b-PEO205 1:2 and J-dimer species at the charge ratio above 1:4, respectively. It is worth noting that the transformation from H-aggregates to J-dimer species of TCPP occurred just by adjusting the ratio of polymer and TCPP rather than by changing other factors such as pH, temperature, and ions.
Growing ZnO Nanoparticles on Polydopamine-Templated Cotton Fabrics for Durable Antimicrobial Activity and UV Protection
Authors: Ran Jianhua , He Mantang , Li Wenbin , Cheng Deshan , Wang Xin
Published: May 2018

This work aims to develop durable functional cotton fabrics by growing zinc oxide (ZnO) nanoparticles on polydopamine (PDA) templates. ZnO nanoparticles were grown on the PDA-templated cotton fabrics by the hydrothermal method at room temperature. The surface morphology, chemical composition, and crystalline structure of the ZnO-coated cotton fabrics were characterized by scanning electron microscope (SEM) with energy dispersive X-ray analysis (EDX), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The ZnO nanoparticles were found to disperse evenly on the surface of cotton fabrics. The ultraviolet (UV) protection factor (UPF) value of the ZnO-coated cotton fabrics was maintained at 122.5, and 99% reduction in bacterial load was observed against Gluconobacter cerinus even after five cycles of laundering. The PDA was found to be effective in fixing the ZnO seeds tightly on the surface of cotton fabrics, resulting in excellent durability of the coating of ZnO nanoparticles.
Planetary Consciousness, Witnessing the Inhuman, and Transformative Learning: Insights from Peace Pilgrimage Oral Histories and Autoethnographies
Authors: Tamashiro Roy
Published: May 2018

This article describes insights and consciousness transformations reported in several contemporary peace pilgrimage oral histories and autoethnographies, including my own. Autoethnography is a form of autobiographical writing that stresses the interpretation of experiences in their psychosocial, cultural, and historical contexts. Peace pilgrimages are typically self-defined journeys and projects which may be inward and metaphorical, or which may involve actual travel to destinations that memorialize historical events of mass killing and profound suffering, and places that envision, cultivate and educate for global or inner peace. The insights and learnings include (a) the call to journey and other out-of-the-ordinary communications; (b) understanding the transformative learning process; (c) glimpsing the meaning of planetary consciousness; and (d) bearing witness to the inhuman. These paradigmatic themes may be applicable to one’s personal search for meaning, and as signposts for collective, societal healing from psychic and social wounding and traumas. The themes may be useful for educators and researchers in peace studies, religious studies, history, biography, philosophy, psychology and consciousness studies.
Coastal Improvements for Tide Models: The Impact of ALES Retracker
Authors: Piccioni Gaia , Dettmering Denise , Passaro Marcello , Schwatke Christian , Bosch Wolfgang , Seitz Florian
Published: May 2018

Since the launch of the first altimetry satellites, ocean tide models have been improved dramatically for deep and shallow waters. However, issues are still found for areas of great interest for climate change investigations: the coastal regions. The purpose of this study is to analyze the influence of the ALES coastal retracker on tide modeling in these regions with respect to a standard open ocean retracker. The approach used to compute the tidal constituents is an updated and along-track version of the Empirical Ocean Tide model developed at DGFI-TUM. The major constituents are derived from a least-square harmonic analysis of sea level residuals based on the FES2014 tide model. The results obtained with ALES are compared with the ones estimated with the standard product. A lower fitting error is found for the ALES solution, especially for distances closer than 20 km from the coast. In comparison with in situ data, the root mean squared error computed with ALES can reach an improvement larger than 2 cm at single locations, with an average impact of over 10% for tidal constituents K 2 , O 1 , and P 1 . For Q 1 , the improvement is over 25%. It was observed that improvements to the root-sum squares are larger for distances closer than 10 km to the coast, independently on the sea state. Finally, the performance of the solutions changes according to the satellite’s flight direction: for tracks approaching land from open ocean root mean square differences larger than 1 cm are found in comparison to tracks going from land to ocean.
Hydrological Regime Monitoring and Mapping of the Zhalong Wetland through Integrating Time Series Radarsat-2 and Landsat Imagery
Authors: Na Xiaodong , Zang Shuying , Wu Changshan , Tian Yang , Li Wenliang
Published: May 2018

Zhalong wetland is a globally important breeding habitat for many rare migratory bird species. Prompted by the high demand for temporal and spatial information about the wetland’s hydrological regimes and landscape patterns, eight time series Radarsat-2 images were utilized to detect the flooding characteristics of the Zhalong wetland. Subsequently, a random forest model was built to discriminate wetlands from other land cover types, combining with optical, radar, and hydrological regime data derived from multitemporal synthetic aperture radar (SAR) images. The results showed that hydrological regimes variables, including flooding extent and flooding frequency, derived from multitemporal SAR images, improve the land cover classification accuracy in the natural wetlands distribution area. The permutation importance scores derived from the random forest classifier indicate that normalized difference vegetation index (NDVI) calculated from optical imagery and the flooding frequency derived from multitemporal SAR imagery were found to be the most important variables for land cover mapping. Accuracy testing indicate that the addition of hydrological regime features effectively depressed the omission error rates (from 52.14% to 2.88%) of marsh and the commission error (from 77.34% to 51.27%) of meadow, thereby improving the overall classification accuracy (from 76.49% to 91.73%). The hydrological regimes and land cover monitoring in the typical wetlands are important for eco-hydrological modeling, biodiversity conservation, and regional ecology and water security.