bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of Toxic Metal Distribution Characteristics and Health Risk between Cultured and Wild Fish Captured from Honghu City, China
Authors: Zhang Jingdong , Zhu Liyun , Li Fei , Liu Chaoyang , Qiu Zhenzhen , Xiao Minsi , Cai Ying
Published: February 2018

Honghu Lake, which listed in the “Ramsar Convention”, is the seventh largest freshwater lake in China and is regarded as one of the biggest freshwater product output areas in China. The toxic element distribution in cultured and wild fish and the corresponding health risks through fish consumption from Honghu area were investigated. The mean concentration in the muscle of cultured and wild fish (Carassius auratus and Ctenopharyngodon idellus) decreased in the order: Zn (18.94) > Cu (0.8489) > Cr (0.2840) > Pb (0.2052) and Zn (16.30) > Cr (1.947) > Cu (0.4166) > Pb (0.0525) > Cd (0.0060) (mean; mg/kg, wet weight). Scales (Multi factor pollution index (MPI) = 3.342) and the liver (MPI = 1.276) were regarded as the main accumulation tissues for cultured fish, and the bladder (MPI = 0.640) and intestine (MPI = 0.477) were regarded as the main accumulation tissues for wild fish. There were no obvious health risks associated with the consumption of cultured and wild fish based on the calculated results of the target hazard quotient (THQ), carcinogenic risk (CR), and estimated weekly intake (EWI). Pb and Cr were recognized as the major health risk contributors for inhabitants through wild and cultured fish consumption. Cultured fish had a greater health risk than wild fish based on the calculation results of THQ and CR. Muscle consumption resulted in more health risks than mixed edible tissues for cultured fish, but for wild fish, the conclusion was the opposite. Mixed fish (cultured:wild = 1:1) muscle consumption had relatively lower risks than the consumption of cultured or wild fish muscle separately. Consuming no more than 465 g/day (wet wt) of cultured fish muscle, 68 g/day (wet wt) of wild fish muscle, 452 g/day (wet wt) of mixed cultured fish edible tissues or 186 g/day (wet wt) of mixed wild fish edible tissues from the Honghu area can assure human health.
AP-1/KIF13A Blocking Peptides Impair Melanosome Maturation and Melanin Synthesis
Authors: Campagne Cécile , Ripoll Léa , Gilles-Marsens Floriane , Raposo Graça , Delevoye Cédric
Published: February 2018

Melanocytes are specialized cells that generate unique organelles called melanosomes in which melanin is synthesized and stored. Melanosome biogenesis and melanocyte pigmentation require the transport and delivery of melanin synthesizing enzymes, such as tyrosinase and related proteins (e.g., TYRP1), from endosomes to maturing melanosomes. Among the proteins controlling endosome-melanosome transport, AP-1 together with KIF13A coordinates the endosomal sorting and trafficking of TYRP1 to melanosomes. We identify here β1-adaptin AP-1 subunit-derived peptides of 5 amino acids that block the interaction of KIF13A with AP-1 in cells. Incubating these peptides with human MNT-1 cells or 3D-reconstructed pigmented epidermis decreases pigmentation by impacting the maturation of melanosomes in fully pigmented organelles. This study highlights that peptides targeting the intracellular trafficking of melanocytes are candidate molecules to tune pigmentation in health and disease.
Effects of TROL Presequence Mutagenesis on Its Import and Dual Localization in Chloroplasts
Authors: Vojta Lea , Čuletić Andrea , Fulgosi Hrvoje
Published: February 2018

Thylakoid rhodanase-like protein (TROL) is involved in the final step of photosynthetic electron transport from ferredoxin to ferredoxin: NADP+ oxidoreductase (FNR). TROL is located in two distinct chloroplast compartments—in the inner envelope of chloroplasts, in its precursor form; and in the thylakoid membranes, in its fully processed form. Its role in the inner envelope, as well as the determinants for its differential localization, have not been resolved yet. In this work we created six N-terminal amino acid substitutions surrounding the predicted processing site in the presequence of TROL in order to obtain a construct whose import is affected or localization limited to a single intrachloroplastic site. By using in vitro transcription and translation and subsequent protein import methods, we found that a single amino acid exchange in the presequence, Ala67 to Ile67 interferes with processing in the stroma and directs the whole pool of in vitro translated TROL to the inner envelope of chloroplasts. This result opens up the possibility of studying the role of TROL in the chloroplast inner envelope as well as possible consequence/s of its absence from the thylakoids.
Proteomic Differences in Feline Fibrosarcomas Grown Using Doxorubicin-Sensitive and -Resistant Cell Lines in the Chick Embryo Model
Authors: Zabielska-Koczywąs Katarzyna , Michalak Katarzyna , Wojtalewicz Anna , Winiarczyk Mateusz , Adaszek Łukasz , Winiarczyk Stanisław , Lechowski Roman
Published: February 2018

Proteomic analyses are rapid and powerful tools that are used to increase the understanding of cancer pathogenesis, discover cancer biomarkers and predictive markers, and select and monitor novel targets for cancer therapy. Feline injection-site sarcomas (FISS) are aggressive skin tumours with high recurrence rates, despite treatment with surgery, radiotherapy, and chemotherapy. Doxorubicin is a drug of choice for soft tissue sarcomas, including FISS. However, multidrug resistance is one of the major causes of chemotherapy failure. The main aim of the present study was to identify proteins that differentiate doxorubicin-resistant from doxorubicin-sensitive FISS using two-dimensional gel electrophoresis (2DE), followed by matrix-assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF MS) analysis. Using the three-dimensional (3D) preclinical in ovo model, which resembles features of spontaneous fibrosarcomas, three significantly (p ≤ 0.05) differentially expressed proteins were identified in tumours grown from doxorubicin-resistant fibrosarcoma cell lines (FFS1 and FFS3) in comparison to the doxorubicin-sensitive one (FFS5): Annexin A5 (ANXA5), Annexin A3 (ANXA3), and meiosis-specific nuclear structural protein 1 (MNS1). Moreover, nine other proteins were significantly differentially expressed in tumours grown from the high doxorubicin-resistant cell line (FFS1) in comparison to sensitive one (FFS5). This study may be the first proteomic fingerprinting of FISS reported, identifying potential candidates for specific predictive biomarkers and research targets for doxorubicin-resistant FISS.
Charged N-terminus of Influenza Fusion Peptide Facilitates Membrane Fusion
Authors: Worch Remigiusz , Dudek Anita , Krupa Joanna , Szymaniec Anna , Setny Piotr
Published: February 2018

Cleavage of hemagglutinin precursor (HA0) by cellular proteases results in the formation of two subunits, HA1 and HA2. The N-terminal fragment of HA2, named a fusion peptide (HAfp), possess a charged, amine N-terminus. It has been shown that the N-terminus of HAfp stabilizes the structure of a helical hairpin observed for a 23-amino acid long peptide (HAfp1-23), whose larger activity than HAfp1-20 has been demonstrated recently. In this paper, we analyze the effect of N-terminal charge on peptide-mediated fusion efficiency and conformation changes at the membrane interface by comparison with the corresponding N-acetylated peptides of 20- and 23-amino acid lengths. We found that higher fusogenic activities of peptides with unmodified amino termini correlates with their ability to form helical hairpin structures oriented perpendicularly to the membrane plane. Molecular dynamics simulations showed that acetylated peptides adopt open and surface-bound conformation more often, which induced less disorder of the phospholipid chains, as compared to species with unmodified amino termini.
Full Annulus Simulations of a Transonic Axial Compressor Stage with Distorted Inflow at Transonic and Subsonic Blade Tip Speed
Authors: Haug Jakob , Niehuis Reinhard
Published: February 2018

This article reports on systematic numerical studies on an axial compressor stage with distorted inflow. Four operating points at two speedlines were simulated with an inflow distortion generated by a 120 ∘ -sector segment with a wedge-type cross-section. With this setup, the interaction between the distorted inflow and the rotor flow was studied. The focus was put on the differences of the interaction between the distorted inflow and rotor flow as well as on the compressor behaviour at subsonic and transonic blade tip speeds, as the general mechanisms have been analysed in more detail in previous publications. The distorted flow itself is not influenced by the blade tip speed, but the interaction phenomena depend strongly on the spool speed and operating point. Additionally, the blade tip speed influences the circumferential sector of the compressor stage exit, which is affected by the distorted flow. The impact reaches from a small sector at 65% spool speed, with the peak efficiency operating point up to nearly the entire annulus at 100% spool speed, near the stall operating point.
“Medium-Scale” Forestland Grabbing in the Southwestern Highlands of Ethiopia: Impacts on Local Livelihoods and Forest Conservation
Authors: Ango Tola Gemechu
Published: February 2018

Tropical forest provides a crucial portion of sustenance in many rural communities, although it is increasingly under pressure from appropriations of various scales. This study investigated the impacts of medium-scale forestland grabbing on local livelihoods and forest conservation in the southwestern highlands of Ethiopia. Data were generated through interviews, discussions and document review. The results indicate that state transfer of part of the forestland since the late 1990s to investors for coffee production created in situ displacement- a situation where farmers remained in place but had fully or partially lost access to forest- that disrupted farmers’ livelihoods and caused conflicts between them and the investors. Court cases about the appropriated land and related imprisonment, inflicted financial and opportunity costs on farmers. Farmers considered the livelihood opportunities created by the companies insufficient to compensate for loss of forest access. Companies’ technology transfers to farmers and contributions to foreign currency earnings from coffee exports have not yet materialized. Forest conservation efforts have been negatively affected by deforestation caused by conversion to coffee plantations and by farmers’ efforts to secure rights to forestland by more intensive use. The medium-scale forestland grabbing has been detrimental to farmers’ livelihoods and forest conservation in a way that recalls criticism of large- and mega-scale land grabbing since 2007–2008. The overall failure to achieve the objectives of transferring forestland to investors highlights a critical need to shift institutional supports to smallholders’ informal forest access and management practices for better development and conservation outcomes.
Dental Application of Natural Products
Authors: Sakagami Hiroshi , Tomomura Mineko
Published: February 2018

This review article summarizes the recent progress in dental applications of natural products. Catechin gel showed selective antimicrobial activity, whereas the alkaline extract of various plant species rich in lignin carbohydrate complex (LCC) showed much higher antiviral activity than lower molecular weight polyphenols. Mouthwash with the alkaline extract of a plant classified as OTC effectively reduced halitosis. Unexpectedly, many polyphenolic compounds purified from the natural kingdom showed much lower tumor-specificity against human oral squamous cell lines as compared with antitumor agents, although they showed apoptosis-inducing activity. The alkaline extract of bamboo leaf, which exerted various common biological activities with LCC, showed osteogenic activity by stimulating differentiation toward osteoblasts while inhibiting differentiation toward osteoclasts. LCC enhanced the dectin-2 mRNA expression in macrophages, whereas glucan showed anti-osteoblastic action via dectin-1. These data suggest that natural products exert their biological activity by interacting with these molecules.
Skeletal Muscle Pathophysiology: The Emerging Role of Spermine Oxidase and Spermidine
Authors: Cervelli Manuela , Leonetti Alessia , Duranti Guglielmo , Sabatini Stefania , Ceci Roberta , Mariottini Paolo
Published: February 2018

Skeletal muscle comprises approximately 40% of the total body mass. Preserving muscle health and function is essential for the entire body in order to counteract chronic diseases such as type II diabetes, cardiovascular diseases, and cancer. Prolonged physical inactivity, particularly among the elderly, causes muscle atrophy, a pathological state with adverse outcomes such as poor quality of life, physical disability, and high mortality. In murine skeletal muscle C2C12 cells, increased expression of the spermine oxidase (SMOX) enzyme has been found during cell differentiation. Notably, SMOX overexpression increases muscle fiber size, while SMOX reduction was enough to induce muscle atrophy in multiple murine models. Of note, the SMOX reaction product spermidine appears to be involved in skeletal muscle atrophy/hypertrophy. It is effective in reactivating autophagy, ameliorating the myopathic defects of collagen VI-null mice. Moreover, spermidine treatment, if combined with exercise, can affect D-gal-induced aging-related skeletal muscle atrophy. This review hypothesizes a role for SMOX during skeletal muscle differentiation and outlines its role and that of spermidine in muscle atrophy. The identification of new molecular pathways involved in the maintenance of skeletal muscle health could be beneficial in developing novel therapeutic lead compounds to treat muscle atrophy.
Active Control of a Small-Scale Wind Turbine Blade Containing Magnetorheological Fluid
Authors: Bolat Fevzi , Sivrioglu Selim
Published: February 2018

This research study proposes a new active control structure to suppress vibrations of a small-scale wind turbine blade filled with magnetorheological (MR) fluid and actuated by an electromagnet. The aluminum blade structure is manufactured using the SH3055 (Bergey Windpower Co. Inc., Norman, OK, USA) code numbered airfoil which is designed for use on small wind turbines. A dynamic interaction model between the MR fluid and the electromagnetic actuator is constructed to obtain a force relation. A detailed characterization study is presented for the proposed actuator to understand the nonlinear behavior of the electromagnetic force. A norm based multi-objective H2/H∞ controller is designed using the model of the elastic blade element. The H2/H∞ controller is experimentally implemented under the impact and steady state aerodynamic load conditions. The results of experiments show that the MR fluid- electromagnetic actuator is effective for suppressing vibrations of the blade structure.
Synthesis, Characterization, and Computational Modeling of N-(1-Ethoxyvinyl)pyridinium Triflates, an Unusual Class of Pyridinium Salts
Authors: Shapiro Jonathan , Sonberg Justin , Schafer Benjamin , Williams Christopher , Ferris Hannah , Reinheimer Eric , Van Wynsberghe Adam , Kriley Charles , Majireck Max
Published: February 2018

N-Substituted pyridinium salts constitute one of the most valuable reagent classes in organic synthesis, due to their versatility and ease of use. Herein we report a preliminary synthesis and detailed structural analysis of several N-(1-ethoxyvinyl)pyridinium triflates, an unusual class of pyridinium salts with potentially broad use as a reagent in organic synthesis. Treatment of pyridines with trifluoromethane sulfonic acid and ethoxyacetylene generates stable, isolable adducts which have been extensively characterized, due to their novelty. Three-dimensional structural stability is perpetuated by an array of C–H•••O hydrogen bonds involving oxygen atoms from the –SO3 groups of the triflate anion, and hydrogen atoms from the aromatic ring and vinyl group of the pyridinium cation. Predictions from density functional theory calculations of the energy landscape for rotation about the exocyclic C–N bond of 2-chloro-1-(1-ethoxyvinyl)pyridine-1-ium trifluoromethanesulfonate (7) and 1-(1-ethoxyvinyl)pyridine-1-ium trifluoromethanesulfonate (16) are also reported. Notably, the predicted global energy minimum of 7 was nearly identical to that found within the crystal structure.
Development of Functional Phthalocyanine-Based Associate towards an Effective Fluorimetric Detection of Hg(II)
Authors: Du Guang-Xin , Zhou Tao , Guo Meng-Lin , Huang Ping , Deng Ya-Bin , Li Dong-Hui
Published: February 2018

In acidic media, cationic phthalocyanine Alcian blue 8GX, has an efficient fluorescence quenching effect on anionic phthalocyanine tetrasulphoaluminium phthalocyanines (AlS4Pc), forming an almost non-fluorescent associate. Based on this discovery, a red-emitting fluorescent probe consisted of AlS4PC and Alcian blue 8GX has been developed through molecular assembly. Further studies indicated that the presence of Hg(II) ion has a significant fluorescence recovery effect of the probe. Notably, only Hg(II) can significantly restore the fluorescence of AlS4Pc-Alcian blue 8GX system which was revealed from the screening experiments of common metal ions, which confirmed that the fluorescence recovery by other metal ions is very weak or even unrestored, showing high specificity and sensitivity AlS4Pc-Alcian blue 8GX to Hg(II). Thus, a new fluorimetry for Hg(II) with high specificity and high sensitivity in a wide concentration range has been established using AlS4Pc-Alcian blue 8GX associate as a red-emitting fluorescent probe. It is more noteworthy that this study opens a new way for development and application of functional phthalocyanine based red-emitting fluorescent probes.
Magnetic Nanoparticles Interact and Pass an In Vitro Co-Culture Blood-Placenta Barrier Model
Authors: Müller Elena , Gräfe Christine , Wiekhorst Frank , Bergemann Christian , Weidner Andreas , Dutz Silvio , Clement Joachim
Published: February 2018

Magnetic nanoparticles are interesting tools for biomedicine. Before application, critical prerequisites have to be fulfilled. An important issue is the contact and interaction with biological barriers such as the blood-placenta barrier. In order to study these processes in detail, suitable in vitro models are needed. For that purpose a blood-placenta barrier model based on the trophoblast-like cell line BeWo and primary placenta-derived pericytes was established. This model was characterized by molecular permeability, transepithelial electrical resistance and cell-cell-contact markers. Superparamagnetic iron oxide nanoparticles (SPIONs) with cationic, anionic or neutral surface charge were applied. The localization of the nanoparticles within the cells was illustrated by histochemistry. The time-dependent passage of the nanoparticles through the BeWo/pericyte barrier was measured by magnetic particle spectroscopy and atomic absorption spectroscopy. Cationically coated SPIONs exhibited the most extensive interaction with the BeWo cells and remained primarily in the BeWo/pericyte cell layer. In contrast, SPIONs with neutral and anionic surface charge were able to pass the cell layer to a higher extent and could be detected beyond the barrier after 24 h. This study showed that the mode of SPION interaction with and passage through the in vitro blood-placenta barrier model depends on the surface charge and the duration of treatment.
Changes in the Anti-Allergic Activities of Sesame by Bioconversion
Authors: Jung Tae-Dong , Choi Sun-Il , Choi Seung-Hyun , Cho Bong-Yeon , Sim Wan-Sup , Han-Xionggao  , Lee Sang , Park Seon , Kim Dan-Bi , Kim Young-Cheul , Lee Jin-Ha , Lee Ok-Hwan
Published: February 2018

Sesame is an important oilseed crop, which has been used as a traditional health food to ameliorate the prevention of various diseases. We evaluated the changes in the anti-allergic activities of sesame by bioconversion. SDS-PAGE of non-fermented sesame proteins showed major allergen bands, while that of fermented sesame showed only a few protein bands. Additionally, we investigated the effectiveness of fermented sesame by bioconversion in tumor necrosis factor-α (TNF-α)- and interferon-γ (IFN-γ)-induced HaCaT cells. In HaCaT cells, fermented sesame inhibited the mRNA expression of interleukin-6 (IL-6) and interleukin-1β (IL-1β), thymus and macrophage-derived chemokine (MDC/CCL22), activation-regulated chemokine (TARC/CCL17), and intercellular adhesion molecule-1 (ICAM-1). Moreover, fermented sesame inhibited the activation of nuclear factor-κB (NF-κB) and signal transducer and activator of transcription 1 (STAT1). Fermented sesame exerts anti-allergic effects by suppressing the expression of chemokines and cytokines via blockade of NF-κB and STAT1 activation.
Claimed Effects, Outcome Variables and Methods of Measurement for Health Claims on Foods Related to Vision Proposed Under Regulation (EC) 1924/2006
Authors: Martini Daniela , Innocenti Augusto , Cosentino Chiara , Bedogni Giorgio , Angelino Donato , Biasini Beatrice , Zavaroni Ivana , Ventura Marco , Galli Daniela , Mirandola Prisco , Vitale Marco , Dei Cas Alessandra , Bonadonna Riccardo C. , Passeri Giovanni , Pruneti Carlo , Del Rio Daniele
Published: February 2018

Adequate visual function has a strong impact on the quality of life of people. Several foods and food components have been hypothesized to play a role in the maintenance of normal visual function and in the prevention of eye diseases. Some of these foods/food components have been the object of a request of authorization for use of health claims under Articles 13(5) or 14 of the Regulation (EC) 1924/2006. Most of these requests have received a negative opinion from the European Food Safety Authority (EFSA) due to the choice of inappropriate outcome variables (OVs) and/or methods of measurement (MMs) applied in the studies used to substantiate the claims. This manuscript refers to the collection, collation and critical analysis of OVs and MMs related to vision. Guidance document and requests for authorization of health claims were used to collect OVs and MMs related to vision. A literature review was performed to critically analyse OVs and MMs, with the aim of defining their appropriateness in the context of a specific claimed effect related to vision. The results highlight the importance of adequate choices of OVs and MMs for an effective substantiation of claims related to visual function.
Understanding the Effect of Particle Size and Processing on Almond Lipid Bioaccessibility through Microstructural Analysis: From Mastication to Faecal Collection
Authors: Mandalari Giuseppina , Parker Mary , Grundy Myriam , Grassby Terri , Smeriglio Antonella , Bisignano Carlo , Raciti Roberto , Trombetta Domenico , Baer David , Wilde Peter
Published: February 2018

We have previously reported on the low lipid bioaccessibility from almond seeds during digestion in the upper gastrointestinal tract (GIT). In the present study, we quantified the lipid released during artificial mastication from four almond meals: natural raw almonds (NA), roasted almonds (RA), roasted diced almonds (DA) and almond butter from roasted almonds (AB). Lipid release after mastication (8.9% from NA, 11.8% from RA, 12.4% from DA and 6.2% from AB) was used to validate our theoretical mathematical model of lipid bioaccessibility. The total lipid potentially available for digestion in AB was 94.0%, which included the freely available lipid resulting from the initial sample processing and the further small amount of lipid released from the intact almond particles during mastication. Particle size distributions measured after mastication in NA, RA and DA showed most of the particles had a size of 1000 µm and above, whereas AB bolus mainly contained small particles (<850 µm). Microstructural analysis of faecal samples from volunteers consuming NA, RA, DA and AB confirmed that some lipid in NA, RA and DA remained encapsulated within the plant tissue throughout digestion, whereas almost complete digestion was observed in the AB sample. We conclude that the structure and particle size of the almond meals are the main factors in regulating lipid bioaccessibility in the gut.
A Survey of Home Enteral Nutrition Practices and Reimbursement in the Asia Pacific Region
Authors: Wong Alvin , Banks Merrilyn D. , Bauer Judith D.
Published: February 2018

Literature regarding the use of home enteral nutrition (HEN) and how it is reimbursed in the Asia Pacific region is limited. This research survey aims to determine the availability of HEN, the type of feeds and enteral access used, national reimbursement policies, the presence of nutrition support teams (NSTs), and clinical nutrition education in this region. An electronic questionnaire was sent to 20 clinical nutrition societies and leaders in the Asia Pacific region in August 2017, where thirteen countries responded. Comparison of HEN reimbursement and practice between countries of different income groups based on the World Bank’s data was investigated. Financial support for HEN is only available in 40% of the countries. An association was found between availability of financial support for HEN and health expenditure (r = 0.63, p = 0.021). High and middle-upper income countries use mainly commercial supplements for HEN, while lower-middle income countries use mainly blenderized diet. The presence of NSTs is limited, and only present mainly in acute settings. Sixty percent of the countries indicated an urgent need for funding and reimbursement of HEN. This survey demonstrates the varied clinical and economic situation in the Asia Pacific region. There is a lack of reimbursement, clinical support, and inadequate educational opportunities, especially for the lower-middle income countries.
Microencapsulation of Phosphorylated Human-Like Collagen-Calcium Chelates for Controlled Delivery and Improved Bioavailability
Authors: Mi Yu , Liu Zhengfang , Deng Jianjun , Lei Huan , Zhu Chenhui , Fan Daidi , Lv Xingqiang
Published: February 2018

The bioavailability of Phosphorylated Human-like Collagen-calcium chelates (PHLC-Ca) as calcium supplement is influenced by the extremely low pH and proteolytic enzymes in the gastrointestinal tract. This study addresses these issues by microencapsulation technology using alginate (ALG) and chitosan (CS) as wall materials. The different ratio of ALG to PHLC-Ca on microcapsules encapsulation efficiency (EE) and loading capacity (LC) was evaluated and 1:1/2 was selected as the optimal proportion. The microcapsules were micron-sized and spherical in shape. PHLC-Ca was successfully entrapped into the matrix of ALG through forming intermolecular hydrogen bonding or other interactions. The confocal laser scanning microscopy (CLSM) indicated that CS was coated on ALG microspheres. The MTT assay exhibited that CS/ALG-(PHLC-Ca) microcapsules extracts were safe to L929. The animal experiment showed that CS/ALG-(PHLC-Ca) microcapsules was superior to treating osteoporosis than PHLC-Ca. These results illustrated that the bioavailability of PHLC-Ca was improved by microencapsulated.
Rheological Behavior of Amino-Functionalized Multi-Walled Carbon Nanotube/Polyacrylonitrile Concentrated Solutions and Crystal Structure of Composite Fibers
Authors: Zhang Hailong , Quan Ling , Shi Fengjun , Li Changqing , Liu Huanqiang , Xu Lianghua
Published: February 2018

The rheological behavior of amino-functionalized multi-walled carbon nanotubes (amino-CNTs)/polyacrylonitrile (PAN) concentrated solutions in the dimethyl sulphoxide solvent and the effects of the amino-CNTs on the PAN precursor fibers by wet-spinning method were investigated. The amino-CNT/PAN concentrated solutions prepared by in situ solution polymerization with homogeneous dispersion of amino-CNTs have higher complex viscosity, storage modulus and loss modulus as compared to the control PAN concentrated solutions containing 22% PAN polymer by mass. The composite fibers with amino-CNTs of 1 wt % have lower degree of crystallization, crystal size and crystal region orientation compared to the control PAN precursor fibers. However, the amino-CNT/PAN composite fibers with diameter of about 10.5 μm exhibit higher mechanical properties than the control PAN precursor fibers with diameter of about 8.0 μm. Differential scanning calorimetry analysis demonstrated that the cyclization reaction in composite fibers have broad exothermic temperature range and low exothermic rate. These results indicate that the addition of amino-CNTs into PAN precursor fibers is beneficial to controlling the process of thermal stabilization and obtaining the higher performance of composite fibers.
Tuning Light Emission towards White Light from a Naphthalenediimide-Based Entangled Metal-Organic Framework by Mixing Aromatic Guest Molecules
Authors: Sola-Llano Rebeca , Martínez-Martínez Virginia , Furukawa Shuhei , Takashima Yohei , López-Arbeloa Iñigo
Published: February 2018

Taking advantage of the outstanding properties of a naphthalenediimide-based entangled porous coordination polymer, a simple strategy for the achievement of white light emission is herein presented. The dynamic structural transformation of the [Zn2(bdc)2(dpNDI)]n metal-organic framework enhances the interactions with aryl-guests giving rise to different luminescence colors upon UV (ultraviolet) illumination. Thus, through the rational selection of those small aromatic guest molecules with different electron donor substituents at the appropriate proportion, the emission color was tuned by mixture ratio of guest molecules and even white light emission was achieved. Furthermore, domains in large crystals with a complementary response to linearly polarized light were noticed.
Polymer@gold Nanoparticles Prepared via RAFT Polymerization for Opto-Biodetection
Authors: Pereira Sónia , Barros-Timmons Ana , Trindade Tito
Published: February 2018

Colloidal gold nanoparticles (Au NPs) have been used in several biological applications, which include the exploitation of size- and shape-dependent Localized Surface Plasmon Resonance (LSPR) in biosensing devices. In order to obtain functional and stable Au NPs in a physiological medium, surface modification and functionalization are crucial steps in these endeavors. Reversible addition-fragmentation chain transfer (RAFT) polymerization meets this need offering the possibility of control over the composition and architecture of polymeric shells coating Au NPs. Furthermore, playing with a careful choice of monomers, RAFT polymerization allows the possibility to design a polymer shell with the desired functional groups aiming at Au based nanocomposites suitable for biorecognition and biotargeting. This review provides important aspects concerning the synthesis and optical properties of Au NPs as well as concepts of RAFT polymerization. Understanding these concepts is crucial to appreciate the chemical strategies available towards RAFT-polymer coated Au core-shell nanostructures, which are here reviewed. Finally, examples of applications in opto-biodetection devices are provided and the potential of responsive “smart” nanomaterials based on such structures can be applied to other biological applications.
Novel Unsupervised Classification of Collapsed Buildings Using Satellite Imagery, Hazard Scenarios and Fragility Functions
Authors: Moya Luis , Marval Perez Luis , Mas Erick , Adriano Bruno , Koshimura Shunichi , Yamazaki Fumio
Published: February 2018

Although supervised machine learning classification techniques have been successfully applied to detect collapsed buildings, there is still a major problem that few publications have addressed. The success of supervised machine learning strongly depends on the availability of training samples. Unfortunately, in the aftermath of a large-scale disaster, training samples become available only after several weeks or even months. However, following a disaster, information on the damage situation is one of the most important necessities for rapid search-and-rescue efforts and relief distribution. In this paper, a modification of the supervised machine learning classification technique called logistic regression is presented. Here, the training samples are replaced with probabilistic information, which is calculated from the spatial distribution of the hazard under consideration and one or more fragility functions. Such damage probabilities can be collected almost in real time for specific disasters such as earthquakes and/or tsunamis. We present the application of the proposed method to the 2011 Great East Japan Earthquake and Tsunami for collapsed building detection. The results show good agreement with a field survey performed by the Ministry of Land, Infrastructure, Transport and Tourism, with an overall accuracy of over 80%. Thus, the proposed method can significantly contribute to a rapid estimation of the number and locations of collapsed buildings.
Circular Array of Magnetic Sensors for Current Measurement: Analysis for Error Caused by Position of Conductor
Authors: Yu Hao , Qian Zheng , Liu Huayi , Qu Jiaqi
Published: February 2018

This paper analyzes the measurement error, caused by the position of the current-carrying conductor, of a circular array of magnetic sensors for current measurement. The circular array of magnetic sensors is an effective approach for AC or DC non-contact measurement, as it is low-cost, light-weight, has a large linear range, wide bandwidth, and low noise. Especially, it has been claimed that such structure has excellent reduction ability for errors caused by the position of the current-carrying conductor, crosstalk current interference, shape of the conduction cross-section, and the Earth’s magnetic field. However, the positions of the current-carrying conductor—including un-centeredness and un-perpendicularity—have not been analyzed in detail until now. In this paper, for the purpose of having minimum measurement error, a theoretical analysis has been proposed based on vector inner and exterior product. In the presented mathematical model of relative error, the un-center offset distance, the un-perpendicular angle, the radius of the circle, and the number of magnetic sensors are expressed in one equation. The comparison of the relative error caused by the position of the current-carrying conductor between four and eight sensors is conducted. Tunnel magnetoresistance (TMR) sensors are used in the experimental prototype to verify the mathematical model. The analysis results can be the reference to design the details of the circular array of magnetic sensors for current measurement in practical situations.
Analysing the Zenith Tropospheric Delay Estimates in On-line Precise Point Positioning (PPP) Services and PPP Software Packages
Authors: Mendez Astudillo Jorge , Lau Lawrence , Tang Yu-Ting , Moore Terry
Published: February 2018

As Global Navigation Satellite System (GNSS) signals travel through the troposphere, a tropospheric delay occurs due to a change in the refractive index of the medium. The Precise Point Positioning (PPP) technique can achieve centimeter/millimeter positioning accuracy with only one GNSS receiver. The Zenith Tropospheric Delay (ZTD) is estimated alongside with the position unknowns in PPP. Estimated ZTD can be very useful for meteorological applications, an example is the estimation of water vapor content in the atmosphere from the estimated ZTD. PPP is implemented with different algorithms and models in online services and software packages. In this study, a performance assessment with analysis of ZTD estimates from three PPP online services and three software packages is presented. The main contribution of this paper is to show the accuracy of ZTD estimation achievable in PPP. The analysis also provides the GNSS users and researchers the insight of the processing algorithm dependence and impact on PPP ZTD estimation. Observation data of eight whole days from a total of nine International GNSS Service (IGS) tracking stations spread in the northern hemisphere, the equatorial region and the southern hemisphere is used in this analysis. The PPP ZTD estimates are compared with the ZTD obtained from the IGS tropospheric product of the same days. The estimates of two of the three online PPP services show good agreement (<1 cm) with the IGS ZTD values at the northern and southern hemisphere stations. The results also show that the online PPP services perform better than the selected PPP software packages at all stations.
Using Unmanned Aerial Vehicles in Postfire Vegetation Survey Campaigns through Large and Heterogeneous Areas: Opportunities and Challenges
Authors: Fernández-Guisuraga José , Sanz-Ablanedo Enoc , Suárez-Seoane Susana , Calvo Leonor
Published: February 2018

This study evaluated the opportunities and challenges of using drones to obtain multispectral orthomosaics at ultra-high resolution that could be useful for monitoring large and heterogeneous burned areas. We conducted a survey using an octocopter equipped with a Parrot SEQUOIA multispectral camera in a 3000 ha framework located within the perimeter of a megafire in Spain. We assessed the quality of both the camera raw imagery and the multispectral orthomosaic obtained, as well as the required processing capability. Additionally, we compared the spatial information provided by the drone orthomosaic at ultra-high spatial resolution with another image provided by the WorldView-2 satellite at high spatial resolution. The drone raw imagery presented some anomalies, such as horizontal banding noise and non-homogeneous radiometry. Camera locations showed a lack of synchrony of the single frequency GPS receiver. The georeferencing process based on ground control points achieved an error lower than 30 cm in X-Y and lower than 55 cm in Z. The drone orthomosaic provided more information in terms of spatial variability in heterogeneous burned areas in comparison with the WorldView-2 satellite imagery. The drone orthomosaic could constitute a viable alternative for the evaluation of post-fire vegetation regeneration in large and heterogeneous burned areas.
Gradient-Type Magnetoelectric Current Sensor with Strong Multisource Noise Suppression
Authors: Zhang Mingji , Or Siu
Published: February 2018

A novel gradient-type magnetoelectric (ME) current sensor operating in magnetic field gradient (MFG) detection and conversion mode is developed based on a pair of ME composites that have a back-to-back capacitor configuration under a baseline separation and a magnetic biasing in an electrically-shielded and mechanically-enclosed housing. The physics behind the current sensing process is the product effect of the current-induced MFG effect associated with vortex magnetic fields of current-carrying cables (i.e., MFG detection) and the MFG-induced ME effect in the ME composite pair (i.e., MFG conversion). The sensor output voltage is directly obtained from the gradient ME voltage of the ME composite pair and is calibrated against cable current to give the current sensitivity. The current sensing performance of the sensor is evaluated, both theoretically and experimentally, under multisource noises of electric fields, magnetic fields, vibrations, and thermals. The sensor combines the merits of small nonlinearity in the current-induced MFG effect with those of high sensitivity and high common-mode noise rejection rate in the MFG-induced ME effect to achieve a high current sensitivity of 0.65–12.55 mV/A in the frequency range of 10 Hz–170 kHz, a small input-output nonlinearity of <500 ppm, a small thermal drift of <0.2%/℃ in the current range of 0–20 A, and a high common-mode noise rejection rate of 17–28 dB from multisource noises.
Error Modelling for Multi-Sensor Measurements in Infrastructure-Free Indoor Navigation
Authors: Ruotsalainen Laura , Kirkko-Jaakkola Martti , Rantanen Jesperi , Mäkelä Maija
Published: February 2018

The long-term objective of our research is to develop a method for infrastructure-free simultaneous localization and mapping (SLAM) and context recognition for tactical situational awareness. Localization will be realized by propagating motion measurements obtained using a monocular camera, a foot-mounted Inertial Measurement Unit (IMU), sonar, and a barometer. Due to the size and weight requirements set by tactical applications, Micro-Electro-Mechanical (MEMS) sensors will be used. However, MEMS sensors suffer from biases and drift errors that may substantially decrease the position accuracy. Therefore, sophisticated error modelling and implementation of integration algorithms are key for providing a viable result. Algorithms used for multi-sensor fusion have traditionally been different versions of Kalman filters. However, Kalman filters are based on the assumptions that the state propagation and measurement models are linear with additive Gaussian noise. Neither of the assumptions is correct for tactical applications, especially for dismounted soldiers, or rescue personnel. Therefore, error modelling and implementation of advanced fusion algorithms are essential for providing a viable result. Our approach is to use particle filtering (PF), which is a sophisticated option for integrating measurements emerging from pedestrian motion having non-Gaussian error characteristics. This paper discusses the statistical modelling of the measurement errors from inertial sensors and vision based heading and translation measurements to include the correct error probability density functions (pdf) in the particle filter implementation. Then, model fitting is used to verify the pdfs of the measurement errors. Based on the deduced error models of the measurements, particle filtering method is developed to fuse all this information, where the weights of each particle are computed based on the specific models derived. The performance of the developed method is tested via two experiments, one at a university’s premises and another in realistic tactical conditions. The results show significant improvement on the horizontal localization when the measurement errors are carefully modelled and their inclusion into the particle filtering implementation correctly realized.
Robust Automatic Target Recognition via HRRP Sequence Based on Scatterer Matching
Authors: Jiang Yuan , Li Yang , Cai Jinjian , Wang Yanhua , Xu Jia
Published: February 2018

High resolution range profile (HRRP) plays an important role in wideband radar automatic target recognition (ATR). In order to alleviate the sensitivity to clutter and target aspect, employing a sequence of HRRP is a promising approach to enhance the ATR performance. In this paper, a novel HRRP sequence-matching method based on singular value decomposition (SVD) is proposed. First, the HRRP sequence is decoupled into the angle space and the range space via SVD, which correspond to the span of the left and the right singular vectors, respectively. Second, atomic norm minimization (ANM) is utilized to estimate dominant scatterers in the range space and the Hausdorff distance is employed to measure the scatter similarity between the test and training data. Next, the angle space similarity between the test and training data is evaluated based on the left singular vector correlations. Finally, the range space matching result and the angle space correlation are fused with the singular values as weights. Simulation and outfield experimental results demonstrate that the proposed matching metric is a robust similarity measure for HRRP sequence recognition.
Developing Socio-Techno-Economic-Political (STEP) Solutions for Addressing Resource Nexus Hotspots
Authors: Daher Bassel , Mohtar Rabi , Pistikopoulos Efstratios , Portney Kent , Kaiser Ronald , Saad Walid
Published: February 2018

The challenge of meeting increasing water, energy, and food needs is linked not only to growing demands globally, but also to the growing interdependency between these interconnected resource systems. Pressures on these systems will emerge to become hotspots with different characteristics, and will require a fresh look at the challenges existing both within each of the resource systems and at their respective interfaces. Proposing solutions to address different resource hotspots must be multi-faceted and need to acknowledge the multiple dimensions of the biophysical water, energy, and food systems, and the players connected with them. This commentary first explores the multiple dimensions of water, energy, and food systems as these relate to government, business, and society. It then identifies contemporary critical questions at the interface of these stressed resource systems. A 3-Filter framework is then introduced for vetting the feasibility of proposed resource allocation scenarios and to account for the bio-physical resource interactions and trade-offs, the stakeholder interactions and trade-offs, and to address governance and financing schemes for carrying forward the implementation of those scenarios.
Perceptions, Preferences, and Behavior Regarding Energy and Environmental Costs: The Case of Montreal Transport Users
Authors: Daher Nayer , Yasmin Farhana , Wang Min Ru , Moradi Ehsan , Rouhani Omid
Published: February 2018

Providing travel-related fuel and environmental information to transport users is becoming increasingly relevant. However, the impact of providing such information on users’ travel behavior is yet to be determined. This research examined the perceptions and preferences related to the fuel consumption costs, greenhouse gas (GHG) social costs, and health-related air pollution costs, and the influence such information could have on travel behavior. Examining the case of Montreal transport users, the authors conducted a survey in which the respondents were asked general and stated preference questions. The respondents were found to be unaware of the energy and environmental footprints of their travel. Approximately 85% of the respondents were not able to estimate GHG social costs and health-related air pollution costs across different modes. The respondents generally overestimated these costs and they interestingly reported higher environmental costs for public transport (metro) compared to cars. They also preferred to receive such information in monetary units, and they were more comfortable in receiving the information through mobile applications over other tools/means. The research also found that fuel and environmental information influence respondents’ travel decisions especially their route choices. Finally, the respondents would be willing to pay an average of 7 Canadian dollars/month in exchange for obtaining the information.
Evaluating Tourist Destination Performance: Expanding the Sustainability Concept
Authors: Luo Wenbin
Published: February 2018

Performance evaluations are a critical tool in promoting the sustainability of tourist destinations. The literature shows a lack of consensus on basic terminology and definitions of destination performance. While research focuses on business efficiency, areas such as development effectiveness, social equality, and environmental integrity are still not well understood, even though these are salient elements of sustainable development. This paper provides a framework for evaluating destination performance under the 4E rubric of economy, efficiency, effectiveness, and environmental quality, which reflects a more holistic and effective destination performance. The information entropy weight method and a multi-factor comprehensive evaluation model are developed and applied to an international destination, Zhangjiajie, China, which was selected as a case study to test the framework developed. Results show that the economy, efficiency, effectiveness, and environmental quality aspects should be considered when evaluating tourism development performance. The empirical analysis shows that based on these criteria, Zhangjiajie’s destination performance improved measurably during the test period from 2005 to 2009. The results indicate that significant events, natural disasters, and financial crises influence performance most.