bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparation of Monolayer Photonic Crystals from Ag Nanobulge-Deposited SiO2 Particles as Substrates for Reproducible SERS Assay of Trace Thiol Pesticide
Authors: Zhang Changbo , Xu Jiying , Chen Yi
Published: June 2020

Surface-enhanced Raman scattering (SERS) greatly increases the detection sensitivity of Raman scattering. However, its real applications are often degraded due to the unrepeatable preparation of SERS substrates. Herein presented is a very facile and cost-effective method to reproducibly produce a novel type of SERS substrate, a monolayer photonic crystal (PC). With a building block of laboratory-prepared monodisperse SiO2 particles deposited with space-tunable silver nanobulges (SiO2@nAg), a PC substrate was first assembled at the air–water interface through needle tip flowing, then transferred onto a silicon slide by a pulling technique. The transferred monolayer PCs were characterized by SEM and AFM to have a hexagonal close-packed lattice. They could increase Raman scattering intensity by up to 2.2 × 107-fold, as tested with p-aminothiophenol. The relative standard deviations were all below 5% among different substrates or among different locations on the same substrate. The excellent reproducibility was ascribed to the highly ordered structure of PCs, while the very high sensitivity was attributed to the strong hotspot effect caused by the appropriately high density of nanobulges deposited on SiO2 particles and by a closed lattice. The PC substrates were validated to be applicable to the SERS assay of trace thiol pesticides. Thiram pesticide is an example determined in apple juice samples at a concentration 102-fold lower than the food safety standard of China. This method is extendable to the analysis of other Raman-active thiol chemicals in different samples, and the substrate preparation approach can be modified for the fabrication of more PC substrates from other metallic nanobulge-deposited particles rather than silica only.
Skin Carotenoid Level as an Alternative Marker of Serum Total Carotenoid Concentration and Vegetable Intake Correlates with Biomarkers of Circulatory Diseases and Metabolic Syndrome
Authors: Matsumoto Mai , Suganuma Hiroyuki , Shimizu Sunao , Hayashi Hiroki , Sawada Kahori , Tokuda Itoyo , Ihara Kazushige , Nakaji Shigeyuki
Published: June 2020

To confirm the usefulness of noninvasive measurements of skin carotenoids to indicate vegetable intake and to elucidate relationships between skin carotenoid levels and biomarkers of circulatory diseases and metabolic syndrome, we conducted a cross-sectional study on a resident-based health checkup (n = 811; 58% women; 49.5 ± 15.1 years). Skin and serum carotenoid levels were measured via reflectance spectroscopy and high-performance liquid chromatography, respectively. Vegetable intake was estimated using a dietary questionnaire. Levels of 9 biomarkers (body mass index [BMI], brachial-ankle pulse wave velocity [baPWV], systolic and diastolic blood pressure [SBP and DBP], homeostasis model assessment as an index of insulin resistance [HOMA-IR], blood insulin, fasting blood glucose [FBG], triglycerides [TGs], and high-density lipoprotein cholesterol [HDL-C]) were determined. Skin carotenoid levels were significantly positively correlated with serum total carotenoids and vegetable intake (r = 0.678 and 0.210, respectively). In women, higher skin carotenoid levels were significantly associated with lower BMI, SBP, DBP, HOMA-IR, blood insulin, and TGs levels and higher HDL-C levels. In men, it was also significantly correlated with BMI and blood insulin levels. In conclusion, dermal carotenoid level may indicate vegetable intake, and the higher level of dermal carotenoids are associated with a lower risk of circulatory diseases and metabolic syndrome.
Use of Remote Monitoring by E-mail for Long-Term Management of the Classic Ketogenic Diet
Authors: Ferraris Cinzia , Guglielmetti Monica , Tamagni Elisa , Trentani Claudia , De Giorgis Valentina , Pasca Ludovica , Varesio Costanza , Ferraro Ottavia Eleonora , Tagliabue Anna
Published: June 2020

The classic ketogenic diet (cKD) requires constant nutritional monitoring over time both to ensure its effectiveness and to reduce the likelihood of short- and long-term adverse effects. We retrospectively described the use of remote monitoring by e-mail during the first year of follow-up on cKD in 34 children (47% males; age range: 2−17 years) diagnosed with drug-resistant epilepsy (DRE; n = 14) or glucose transporter type 1 deficiency syndrome (GLUT1-DS; n = 20). All the e-mails were evaluated analyzing their frequency and content at 3, 6 and 12 months. Three families never sent e-mails. A median of 36.0 (IQR 23.0–64.0) e-mails per family were sent during the 12 follow-up months by the 31 patients. GLUT1-DS patients sent a greater number of e-mails than the DRE group (median 39.0 (IQR 25.5–56.5) vs. median 26.0 (IQR 19.0–65.0)). At the end of the follow-up period, a greater number of e-mails had been exchanged between the nutritional team and the families belonging to the group that increased its linear growth (median 83.5; IQR 48.0–102.0), compared to the other ones. Constant remote monitoring by e-mail could be a feasible and effective way for a better cKD management.
Parent Stress as a Consideration in Childhood Obesity Prevention: Results from the Guelph Family Health Study, a Pilot Randomized Controlled Trial
Authors: Hruska Valerie , Darlington Gerarda , Haines Jess , Ma David W. L.
Published: June 2020

Parents’ stress is independently associated with increased child adiposity, but parents’ stress may also interfere with childhood obesity prevention programs. The disruptions to the family dynamic caused by participating in a behaviour change intervention may exacerbate parent stress and undermine overall intervention efficacy. This study explored how family stress levels were impacted by participation in a home-based obesity prevention intervention. Data were collected from 77 families (56 fathers, 77 mothers) participating in the Guelph Family Health Study (GFHS), a pilot randomized control trial of a home-based obesity prevention intervention. Four measures of stress were investigated: general life stress, parenting distress, depressive symptoms, and household chaos. Multiple linear regression was used to compare the level of stress between the intervention and control groups at post-intervention and 1-year follow-up, adjusted for baseline stress. Analyses for mothers and fathers were stratified, except for household chaos which was measured at the family level. Results indicate no significant differences between intervention and control groups for any stress measure at any time point, indicating a neutral effect of the GFHS intervention on family stress. Future work should investigate the components of family-based intervention protocols that make participation minimally burdensome and consider embedding specific stress-reduction messaging to promote family health and wellbeing.
Effect of a Flaxseed Lignan Intervention on Circulating Bile Acids in a Placebo-Controlled Randomized, Crossover Trial
Authors: Navarro Sandi L. , Levy Lisa , Curtis Keith R. , Elkon Isaac , Kahsai Orsalem J. , Ammar Hamza S. , Randolph Timothy W. , Hong Natalie N. , Carnevale Neto Fausto , Raftery Daniel , Chapkin Robert S. , Lampe Johanna W. , Hullar Meredith A. J.
Published: June 2020

Plant lignans and their microbial metabolites, e.g., enterolactone (ENL), may affect bile acid (BA) metabolism through interaction with hepatic receptors. We evaluated the effects of a flaxseed lignan extract (50 mg/day secoisolariciresinol diglucoside) compared to a placebo for 60 days each on plasma BA concentrations in 46 healthy men and women (20–45 years) using samples from a completed randomized, crossover intervention. Twenty BA species were measured in fasting plasma using LC-MS. ENL was measured in 24-h urines by GC-MS. We tested for (a) effects of the intervention on BA concentrations overall and stratified by ENL excretion; and (b) cross-sectional associations between plasma BA and ENL. We also explored the overlap in bacterial metabolism at the genus level and conducted in vitro anaerobic incubations of stool with lignan substrate to identify genes that are enriched in response to lignan metabolism. There were no intervention effects, overall or stratified by ENL at FDR < 0.05. In the cross-sectional analysis, irrespective of treatment, five secondary BAs were associated with ENL excretion (FDR < 0.05). In vitro analyses showed positive associations between ENL production and bacterial gene expression of the bile acid-inducible gene cluster and hydroxysteroid dehydrogenases. These data suggest overlap in community bacterial metabolism of secondary BA and ENL.
Nutrihealth Study: Seasonal Variation in Vitamin D Status Among the Slovenian Adult and Elderly Population
Authors: Hribar Maša , Hristov Hristo , Gregorič Matej , Blaznik Urška , Zaletel Katja , Oblak Adrijana , Osredkar Joško , Kušar Anita , Žmitek Katja , Rogelj Irena , Pravst Igor
Published: June 2020

Several studies conducted around the world showed substantial vitamin D insufficiency and deficiency among different population groups. Sources of vitamin D in the human body include ultraviolet B (UVB)-light-induced biosynthesis and dietary intake, but people’s diets are often poor in vitamin D. Furthermore, in many regions, sun exposure and the intensity of UVB irradiation during wintertime are not sufficient for vitamin D biosynthesis. In Slovenia, epidemiological data about vitamin D status in the population were investigated through a national Nutrihealth study—an extension to the national dietary survey SI.Menu (2017/18). The study was conducted on a representative sample of 125 adult (18–64 years) and 155 elderly (65–74 years old) subjects, enrolled in the study in different seasons. Their vitamin D status was determined by measuring the serum 25-hydroxy-vitamin D (25(OH)D) concentration. Thresholds for vitamin D deficiency and insufficiency were 25(OH)D levels below 30 and 50 nmol/L, respectively. Altogether, 24.9% of the adults and 23.5% of the elderly were found to be vitamin D deficient, while an insufficient status was found in 58.2% and 62.9%, respectively. A particularly concerning situation was observed during extended wintertime (November–April); vitamin D deficiency was found in 40.8% and 34.6%, and insufficient serum 25(OH)D levels were observed in 81.6% and 78.8%, respectively. The results of the study showed high seasonal variation in serum 25(OH)D levels in both the adult and elderly population, with deficiency being especially pronounced during wintertime. The prevalence of this deficiency in Slovenia is among the highest in Europe and poses a possible public health risk that needs to be addressed with appropriate recommendations and/or policy interventions.
Recent Advances in the Design of Topical Ophthalmic Delivery Systems in the Treatment of Ocular Surface Inflammation and Their Biopharmaceutical Evaluation
Authors: Mazet Roseline , Yaméogo Josias B. G. , Wouessidjewe Denis , Choisnard Luc , Gèze Annabelle
Published: June 2020

Ocular inflammation is one of the most common symptom of eye disorders and diseases. The therapeutic management of this inflammation must be rapid and effective in order to avoid deleterious effects for the eye and the vision. Steroidal (SAID) and non-steroidal (NSAID) anti-inflammatory drugs and immunosuppressive agents have been shown to be effective in treating inflammation of the ocular surface of the eye by topical administration. However, it is well established that the anatomical and physiological ocular barriers are limiting factors for drug penetration. In addition, such drugs are generally characterized by a very low aqueous solubility, resulting in low bioavailability as only 1% to 5% of the applied drug permeates the cornea. The present review gives an updated insight on the conventional formulations used in the treatment of ocular inflammation, i.e., ointments, eye drops, solutions, suspensions, gels, and emulsions, based on the commercial products available on the US, European, and French markets. Additionally, sophisticated formulations and innovative ocular drug delivery systems will be discussed. Promising results are presented with micro- and nanoparticulated systems, or combined strategies with polymers and colloidal systems, which offer a synergy in bioavailability and sustained release. Finally, different tools allowing the physical characterization of all these delivery systems, as well as in vitro, ex vivo, and in vivo evaluations, will be considered with regards to the safety, the tolerance, and the efficiency of the drug products.
Emergency Contraception Access and Counseling in Urban Pharmacies: A Comparison between States with and without Pharmacist Prescribing
Authors: Stone Rebecca H. , Rafie Sally , Ernest Dennia , Scutt Brielle
Published: June 2020

Pharmacists are often the primary source of emergency contraception (EC) access and patient information. This study aims to identify differences in pharmacist-reported EC access and counseling between states which do or do not permit pharmacist-prescribed EC. This prospective, mystery caller study was completed in California (CA), which permits pharmacist-prescribed EC after completion of continuing education, and Georgia (GA), which does not. All community pharmacies that were open to the public in San Diego and San Francisco, CA, and Atlanta, GA were called by researchers who posed as adult females inquiring about EC via a structured script. Primary endpoints were EC availability and counseling. Statistical analyses completed with SPSS. Researchers called 395 pharmacies, 98.2% were reached and included. Regarding levonorgestrel (LNG), CA pharmacists more frequently discussed (CA 90.4% vs. GA 81.2%, p = 0.02), stocked (CA 89.5% vs. GA 67.8%, p < 0.01), and correctly indicated it “will work” or “will work but may be less effective” 4 days after intercourse (CA 67.5% vs. GA 17.5%, p < 0.01). Ulipristal was infrequently discussed (CA 22.6% vs. GA 3.4%, p < 0.01) and rarely stocked (CA 9.6% vs. GA 0.7%, p < 0.01). Pharmacists practicing in states which permit pharmacist-prescribed EC with completion of required continuing education may be associated with improved patient access to oral EC and more accurate patient counseling.
Involvement of Allelopathy in the Invasive Potential of Tithonia diversifolia
Authors: Kato-Noguchi Hisashi
Published: June 2020

Tithonia diversifolia (Hemsl.) A. Gray (Asteraceae) is native to Mexico and Central America. The species is spreading quickly and has naturalized in more than 70 countries. It has often been recorded as a harmful invasive plant that disturbs native plant communities. Phytotoxic chemical interactions such as allelopathy between invasive plants and native plants have been reported to play an important role in the invasion. Evidence for allelopathy of T. diversifolia has accumulated in the literature over 30 years. Thus, the objective of this review was to discuss the possible involvement of allelopathy in the invasive potential of T. diversifolia. The extracts, root exudates, and plant residues of T. diversifolia inhibited the germination and growth of other plant species. The soil water and soil collected from T. diversifolia fields also showed inhibitory growth effects. The decomposition rate of T. diversifolia residues in soil was reported to be high. Phytotoxic substances such as sesquiterpene lactones were isolated and identified in the extracts of T. diversifolia. Some phytotoxic substances in T. diversifolia may be released into the soil through the decomposition of the plant residues and the exudation from living tissues of T. diversifolia, including its root exudates, which act as allelopathic substances. Those allelopathic substances can inhibit the germination and growth of neighboring plants and may enhance the competitive ability of the plants, make them invasive.
Cucumber Fruit Size and Shape Variations Explored from the Aspects of Morphology, Histology, and Endogenous Hormones
Authors: Liu Xiaoxiao , Pan Yupeng , Liu Ce , Ding Yuanyuan , Wang Xiao , Cheng Zhihui , Meng Huanwen
Published: June 2020

Fruit size and shape are important qualities and yield traits in cucumber (Cucumis sativus L.), but the factors that influence fruit size and shape remain to be explored. In this study, we investigated the dynamic changes of fruit size and shape from the aspects of morphology, cellular levels and endogenous hormones for nine typical cucumber inbred lines. The results show that fruit length had a strong positive correlation to the cell number in the longitudinal section of fruit throughout the four stages of 0, 6, 12, and 30 DAA (days after anthesis). However, the significant negative correlations were found between fruit length and the fruit cell size at 12 and 30 DAA. Furthermore, fruit diameter was positively correlated to the cell number in the cross section at all the investigated fruit growth stages. The indole-3-acetic acid (IAA) content showed significant positive correlations to the fruit length at all fruit growth stages of −6, −3, 0, 3, 6, 9 and 12 DAA, but IAA content and fruit diameter showed significant negative correlations for all the stages except for at −6 DAA. The trans-zeatin riboside (tZR), zeatin (ZT), gibberellic acid (GA3) and jasmonic acid (JA) content had a positive or negative correlation with fruit length or diameter only at certain stages. Neither fruit length nor diameter had significant correlations to abscisic acid (ABA) content. These results indicate that variations in fruit size and shape of different cucumber inbred lines mainly result from the differences in fruit cell number and endogenous IAA content. The present work is the first to propose cucumber fruit size and shape changes from the combined aspects of morphology, cellular levels, and endogenous hormones.
Highlight on the Mechanism of Linear Polyamidoamine Degradation in Water
Authors: Arioli Matteo , Manfredi Amedea , Alongi Jenny , Ferruti Paolo , Ranucci Elisabetta
Published: June 2020

This paper aims at elucidating the degradation mechanism of linear polyamidoamines (PAAs) in water. PAAs are synthesized by the aza-Michael polyaddition of prim-monoamines or bis-sec-amines with bisacrylamides. Many PAAs are water-soluble and have potential for biotechnological applications and as flame-retardants. PAAs have long been known to degrade in water at pH ≥ 7, but their degradation mechanism has never been explored in detail. Filling this gap was necessary to assess the suitability of PAAs for the above applications. To this aim, a small library of nine PAAs was expressly synthesized and their degradation mechanism in aqueous solution studied by 1H-NMR in different conditions of pH and temperature. The main degradation mechanism was in all cases the retro-aza-Michael reaction triggered by dilution but, in some cases, hints were detected of concurrent hydrolytic degradation. Most PAAs were stable at pH 4.0; all degraded at pH 7.0 and 9.0. Initially, the degradation rate was faster at pH 9.0 than at pH 7.0, but the percent degradation after 97 days was mostly lower. In most cases, at pH 7.0 the degradation followed first order kinetics. The degradation rates mainly depended on the basicity of the amine monomers. More basic amines acted as better leaving groups.
Synthesis and Characterization of a 2,3-Dialkoxynaphthalene-Based Conjugated Copolymer via Direct Arylation Polymerization (DAP) for Organic Electronics
Authors: Jessop Ignacio A. , Chong Aylin , Graffo Linda , Camarada María B. , Espinoza Catalina , Angel Felipe A. , Saldías Cesar , Tundidor-Camba Alain , Terraza Claudio A.
Published: June 2020

Poly[(5,5’-(2,3-bis(2-ethylhexyloxy)naphthalene-1,4-diyl)bis(thiophene-2,2′-diyl))-alt-(2,1,3-benzothiadiazole-4,7-diyl)] (PEHONDTBT) was synthesized for the first time and through direct arylation polymerization (DAP) for use as p-donor material in organic solar cells. Optimized reaction protocol leads to a donor-acceptor conjugated polymer in good yield, with less structural defects than its analog obtained from Suzuki polycondensation, and with similar or even higher molecular weight than other previously reported polymers based on the 2,3-dialkoxynaphthalene monomer. The batch-to-batch repeatability of the optimized DAP conditions for the synthesis of PEHONDTBT was proved, showing the robustness of the synthetic strategy. The structure of PEHONDTBT was corroborated by NMR, exhibiting good solubility in common organic solvents, good film-forming ability, and thermal stability. PEHONDTBT film presented an absorption band centered at 498 nm, a band gap of 2.15 eV, and HOMO and LUMO energy levels of −5.31 eV and −3.17 eV, respectively. Theoretical calculations were performed to understand the regioselectivity in the synthesis of PEHONDTBT and to rationalize its optoelectronic properties. Bilayer heterojunction organic photovoltaic devices with PEHONDTBT as the donor layer were fabricated to test their photovoltaic performance, affording low power-conversion efficiency in the preliminary studies.
Micro/Nanoscale Structured Superhydrophilic and Underwater Superoleophobic Hybrid-Coated Mesh for High-Efficiency Oil/Water Separation
Authors: Yuan Teng , Yin Jian , Liu Yingling , Tu Weiping , Yang Zhuohong
Published: June 2020

A novel micro/nanoscale rough structured superhydrophilic hybrid-coated mesh that shows underwater superoleophobic behavior is fabricated by spray casting or dipping nanoparticle–polymer suspensions on stainless steel mesh substrates. Water droplets can spread over the mesh completely; meanwhile, oil droplets can roll off the mesh at low tilt angles without any penetration. Besides overcoming the oil-fouling problem of many superhydrophilic coatings, this superhydrophilic and underwater superoleophobic mesh can be used to separate oil and water. The simple method used here to prepare the organic–inorganic hybrid coatings successfully produced controllable micro-nano binary roughness and also achieved a rough topography of micro-nano binary structure by controlling the content of inorganic particles. The mechanism of oil–water separation by the superhydrophilic and superoleophobic membrane is rationalized by considering capillary mechanics. Tetraethyl orathosilicate (TEOS) as a base was used to prepare the nano-SiO2 solution as a nano-dopant through a sol-gel process, while polyvinyl alcohol (PVA) was used as the film binder and glutaraldehyde as the cross-linking agent; the mixture was dip-coated on the surface of 300-mesh stainless steel mesh to form superhydrophilic and underwater superoleophobic film. Properties of nano-SiO2 represented by infrared spectroscopy and surface topography of the film observed under scanning electron microscope (SEM) indicated that the film surface had a coarse micro–nano binary structure; the effect of nano-SiO2 doping amount on the film’s surface topography and the effect of such surface topography on hydrophilicity of the film were studied; contact angle of water on such surface was tested as 0° by the surface contact angle tester and spread quickly; the underwater contact angle to oil was 158°, showing superhydrophilic and underwater superoleophobic properties. The effect of the dosing amount of cross-linking agent to the waterproof swelling property and the permeate flux of the film were studied; the oil–water separation effect of the film to oil–water suspension and oil–water emulsion was studied too, and in both cases the separation efficiency reached 99%, which finally reduced the oil content to be lower than 50 mg/L. The effect of filtration times to permeate flux was studied, and it was found that the more hydrophilic the film was, the stronger the stain resistance would be, and the permeate flux would gradually decrease along with the increase of filtration times.
A Study of the Reinforcement Effect of MWCNTs onto Polyimide Flat Sheet Membranes
Authors: Sapalidis Andreas A. , Karantzis Panagiotis I. , Vairis Achilles , Nitodas Stephanos F. , Barbe Stéphan , Favvas Evangelos P.
Published: June 2020

Polyimides rank among the most heat-resistant polymers and find application in a variety of fields, including transportation, electronics, and membrane technology. The aim of this work is to study the structural, thermal, mechanical, and gas permeation properties of polyimide based nanocomposite membranes in flat sheet configuration. For this purpose, numerous advanced techniques such as atomic force microscopy (AFM), SEM, TEM, TGA, FT-IR, tensile strength, elongation test, and gas permeability measurements were carried out. In particular, BTDA–TDI/MDI (Ρ84) co-polyimide was used as the matrix of the studied membranes, whereas multi-wall carbon nanotubes were employed as filler material at concentrations of up to 5 wt.% All studied films were prepared by the dry-cast process resulting in non-porous films of about 30–50 μm of thickness. An optimum filler concentration of 2 wt.% was estimated. At this concentration, both thermal and mechanical properties of the prepared membranes were improved, and the highest gas permeability values were also obtained. Finally, gas permeability experiments were carried out at 25, 50, and 100 °C with seven different pure gases. The results revealed that the uniform carbon nanotubes dispersion lead to enhanced gas permeation properties.
Effects of Chemical Modifications on the Thermoresponsive Behavior of a PDMAEA-b-PNIPAM-b-POEGA Triblock Terpolymer
Authors: Giaouzi Despoina , Pispas Stergios
Published: June 2020

In this work, the synthesis, selective chemical modifications, and self-assembly behavior in aqueous media of a novel poly(2-(dimethylamino)ethyl acrylate)20-b-poly(N-isopropylacrylamide)11-b-poly(oligo ethylene glycol methyl ether acrylate)18 (PDMAEA20-b-PNIPAM11-b-POEGA18) dual-responsive (pH and temperature) and triply hydrophilic amino-based triblock terpolymer are reported. The amine functional triblock terpolymer was synthesized by sequential reversible addition fragmentation chain transfer polymerization (RAFT) polymerization and molecularly characterized by size exclusion chromatography (SEC) and 1H-NMR spectroscopy that evidenced the success of the three-step polymerization scheme. The tertiary amine pendant groups of the PDMAEA block were chemically modified in order to produce the Q1PDMAEA20-b-PNIPAM11-b-POEGA18 as well as the Q6PDMAEA20-b-PNIPAM11-b-POEGA18 quaternized triblock terpolymers (Q1 and Q6 prefixes show the number of carbon atoms (C1 and C6) attached on the PDMAEA groups) using methyl iodide (CH3I) and 1-iodohexane (C6H13I) as the quaternizing agents and the SPDMAEA20-b-PNIPAM11-b-POEGA18 sulfobetainized triblock terpolymer using 1,3 propanesultone (C3H6O3S) as the sulfobetainization agent. The self-assembly properties of the triblock terpolymers in aqueous solutions upon varying temperature and solution pH were studied by light scattering and fluorescence spectroscopy experiments. The novel triblock terpolymers self-assemble into nanosized aggregates upon solution temperature rise above the nominal lower critical solution temperature (LCST) of the temperature-responsive PNIPAM block. The remarkable stimuli-responsive self-assembly behavior of the novel triblock terpolymers in aqueous media make them interesting candidates for biomedical applications in the fields of drug and gene delivery.
Effect of the Esterification of Starch with a Mixture of Carboxylic Acids from Yarrowia lipolitica Fermentation Broth on Its Selected Properties
Authors: Zdybel Ewa , Zięba Tomasz , Tomaszewska-Ciosk Ewa , Rymowicz Waldemar
Published: June 2020

Potato starch was esterified with carboxylic acids contained in the fermentation broth from Yarrowia lipolitica yeast production. Various acid concentrations and various roasting temperatures were used to determine effects of process conditions on ester properties, including the number of acid residues attached to starch chains, starch susceptibility to amylolysis, and thermal characteristics of starch phase transitions. Study results demonstrated the effect of both the composition and the dose of the fermentation broth and of roasting temperature of starch on the number of acid residues attached to starch chains. Citric acid was more susceptible to esterification with starch (DS = 5.65%) compared to the α-ketoglutaric acid (DS = 0.12%). In the case of the latter, a higher degree of substitution was determined in the esters produced at higher roasting temperatures. The lowest digestibility (RS = 20%) was demonstrated for the starch esters with the highest degree of substitution with citric acid, whereas all starch esters showed decreased values of the thermal characteristics of pasting.
Fabrication of Biopolymer Based Nanoparticles for the Entrapment of Chromium and Iron Supplements
Authors: Patel Nishay , Zariwala Mohammed Gulrez , Al-Obaidi Hisham
Published: June 2020

The objective of this study was to encapsulate iron and chromium into novel nanoparticles formulated using chitosan (CS), dextran sulfate (DS) and whey protein isolate (WPI) for oral drug delivery. Empty and loaded CS-DS nanoparticles were prepared via complex coacervation whilst whey protein nanocarriers were produced by a modified thermal processing method using chitosan. The physiochemical properties of the particles were characterized to determine the effects of formulation variables, including biopolymer ratio on particle size and zeta potential. Permeability studies were also undertaken on the most stable whey protein–iron nanoparticles by measuring Caco-2 ferritin formation. A particle size analysis revealed that the majority of samples were sub-micron sized, ranging from 420–2400 nm for CS-DS particles and 220–1000 nm for WPI-CS samples. As expected, a higher chitosan concentration conferred a 17% more positive zeta potential on chromium-entrapped WPI nanoparticles, whilst a higher dextran volume decreased the size of CS-DS nanoparticles by 32%. The addition of iron also caused a significant increase in size for all samples, as seen where the loaded WPI samples were 296 nm larger than the empty particles. Caco-2 iron absorption revealed that one formulation, which had the lowest particle size (226 ± 10 nm), caused a 64% greater iron absorption compared to the ferrous sulfate standard. This study describes, for the first time, the novel design of chromium- and iron-entrapped nanoparticles, which could act as novel systems for oral drug delivery.
Compact Heat Integrated Reactor System of Steam Reformer, Shift Reactor and Combustor for Hydrogen Production from Ethanol
Authors: Khaodee Watcharapong , Jiwanuruk Tara , Ountaksinkul Khunnawat , Charojrochkul Sumittra , Charoensuk Jarruwat , Wongsakulphasatch Suwimol , Assabumrungrat Suttichai
Published: June 2020

A compact heat integrated reactor system (CHIRS) of a steam reformer, a water gas shift reactor, and a combustor were designed for stationary hydrogen production from ethanol. Different reactor integration concepts were firstly studied using Aspen Plus. The sequential steam reformer and shift reactor (SRSR) was considered as a conventional system. The efficiency of the SRSR could be improved by more than 12% by splitting water addition to the shift reactor (SRSR-WS). Two compact heat integrated reactor systems (CHIRS) were proposed and simulated by using COMSOL Multiphysics software. Although the overall efficiency of the CHIRS was quite a bit lower than the SRSR-WS, the compact systems were properly designed for portable use. CHIRS (I) design, combining the reactors in a radial direction, was large in reactor volume and provided poor temperature control. As a result, the ethanol steam reforming and water gas shift reactions were suppressed, leading to lower hydrogen selectivity. On the other hand, CHIRS (II) design, combining the process in a vertical direction, provided better temperature control. The reactions performed efficiently, resulting in higher hydrogen selectivity. Therefore, the high performance CHIRS (II) design is recommended as a suitable stationary system for hydrogen production from ethanol.
No-Arbitrage Principle in Conic Finance
Authors: Vazifedan Mehdi , Zhu Qiji Jim
Published: June 2020

In a one price economy, the Fundamental Theorem of Asset Pricing (FTAP) establishes that no-arbitrage is equivalent to the existence of an equivalent martingale measure. Such an equivalent measure can be derived as the normal unit vector of the hyperplane that separates the attainable gain subspace and the convex cone representing arbitrage opportunities. However, in two-price financial models (where there is a bid–ask price spread), the set of attainable gains is not a subspace anymore. We use convex optimization, and the conic property of this region to characterize the “no-arbitrage” principle in financial models with the bid–ask price spread present. This characterization will lead us to the generation of a set of price factor random variables. Under such a set, we can find the lower and upper bounds (supper-hedging and sub-hedging bounds) for the price of any future cash flow. We will show that for any given cash flow, for which the price is outside the above range, we can build a trading strategy that provides one with an arbitrage opportunity. We will generalize this structure to any two-price finite-period financial model.
Small Lava Caves as Possible Exploratory Targets on Mars: Analogies Drawn from UAV Imaging of an Icelandic Lava Field
Authors: Sam Lydia , Bhardwaj Anshuman , Singh Shaktiman , Martin-Torres F. Javier , Zorzano Maria-Paz , Ramírez Luque Juan Antonio
Published: June 2020

Volcanic-aeolian interactions and processes have played a vital role in landscape evolution on Mars. Martian lava fields and associated caves have extensive geomorphological, astrobiological, and in-situ resource utilization (ISRU) implications for future Mars missions which might be focused on subsurface exploration. Although several possible cave “skylights” of tens to >100 m diameter have been spotted in lava fields of Mars, there is a possibility of prevalence of meter-scale features which are an order of magnitude smaller and difficult to identify but could have vital significance from the scientific and future exploration perspectives. The Icelandic volcanic-aeolian environment and fissure volcanoes can serve as analogs to study lava flow-related small caves such as surface tubes, inflationary caves, liftup caves, and conduits. In the present work, we have tried to explore the usability of unmanned aerial vehicle (UAV)-derived images for characterizing a solidified lava flow and designing a sequential methodology to identify small caves in the lava flow. In the mapped area of ~0.33 km2, we were able to identify 81 small cave openings, five lava flow morphologies, and five small cave types using 2 cm/pixel high-resolution images. The results display the usefulness of UAV imaging for such analogous research, and also highlight the possibility of the widespread presence of similar small cave openings in Martian lava fields. Such small openings can facilitate optimal air circulation within the caves while sheltering the insides from physical weathering and harmful radiations. Using the available best resolution remote sensing images, we extend the analogy through the contextual and geomorphological analysis of several possible pit craters in the Tharsis region of Mars, in a region of extremely vesicular and fragile lava crust with pahoehoe-type morphology. We report two possible pit craters in this region, with diameters as small as ~20 m. The possibility that such small cave openings can lead to vast subterranean hollow spaces on Mars cannot be ruled out considering its low gravity.
Near Real-Time Freeze Detection over Agricultural Plots Using Sentinel-1 Data
Authors: Fayad Ibrahim , Baghdadi Nicolas , Bazzi Hassan , Zribi Mehrez
Published: June 2020

Short-term freeze/thaw cycles, which mostly occur in the northern hemisphere across the majority of land surfaces, are reported to cause severe economic losses over broad areas of Europe and North America. Therefore, in order to assess the extent of frost damage in the agricultural sector, the objective of this study is to build an operational approach capable of detecting frozen plots at the plot scale in a near real-time scenario using Sentinel-1 (S1) data. C-band synthetic aperture radar (SAR) data show high potential for the detection of freeze/thaw surface states due to the significant alterations to the dielectric properties of the soil, which are distinctly observable in the backscattered signal. In this study, we propose an approach that relies on change detection in the high-resolution Sentinel-1 C-band SAR backscattered coefficients, to determine surface states at the plot scale as either frozen or unfrozen. A threshold analysis is first performed in order to determine the best thresholds for three distinct land cover classes, and for each polarization mode (VH, and VV). S-1 SAR data are then used to detect a plot’s surface state as either unfrozen, mild-to-moderately frozen or severely frozen. A temperature-based filter has also been applied at the end of the detection chain to eliminate false detections in the freezing detection algorithm due mainly to rainfall, irrigation, tillage, or signal noise. Our approach has been tested over two study sites in France, and the output results, using either VH or VV, compared qualitatively well with both in situ air temperature data and soil temperature data provided by ERA5-Land. Overall, our algorithm was able to detect all freezing episodes over the analyzed S-1 SAR time series, and with no false detections. Moreover, given the high-resolution aspect of S-1 SAR data, our algorithm is capable of mapping the local variation of freezing episodes at plot scale. This is in contrast with previous products that only offer coarser results across larger areas (low spatial resolution).
Autonomous Underwater Monitoring System for Detecting Life on the Seabed by Means of Computer Vision Cloud Services
Authors: Salhaoui Marouane , Molina-Molina J. Carlos , Guerrero-González Antonio , Arioua Mounir , Ortiz Francisco J.
Published: June 2020

Autonomous underwater vehicles (AUVs) have increasingly played a key role in monitoring the marine environment, studying its physical-chemical parameters for the supervision of endangered species. AUVs now include a power source and an intelligent control system that allows them to autonomously carry out programmed tasks. Their navigation system is much more challenging than that of land-based applications, due to the lack of connected networks in the marine environment. On the other hand, due to the latest developments in neural networks, particularly deep learning (DL), the visual recognition systems can achieve impressive performance. Computer vision (CV) has especially improved the field of object detection. Although all the developed DL algorithms can be deployed in the cloud, the present cloud computing system is unable to manage and analyze the massive amount of computing power and data. Edge intelligence is expected to replace DL computation in the cloud, providing various distributed, low-latency and reliable intelligent services. This paper proposes an AUV model system designed to overcome latency challenges in the supervision and tracking process by using edge computing in an IoT gateway. The IoT gateway is used to connect the AUV control system to the internet. The proposed model successfully carried out a long-term monitoring mission in a predefined area of shallow water in the Mar Menor (Spain) to track the underwater Pinna nobilis (fan mussel) species. The obtained results clearly justify the proposed system’s design and highlight the cloud and edge architecture performances. They also indicate the need for a hybrid cloud/edge architecture to ensure a real-time control loop for better latency and accuracy to meet the system’s requirements.
DIEER: Delay-Intolerant Energy-Efficient Routing with Sink Mobility in Underwater Wireless Sensor Networks
Authors: Latif Kamran , Javaid Nadeem , Ullah Imdad , Kaleem Zeeshan , Abbas Malik Zafar , Nguyen Long D.
Published: June 2020

Underwater Wireless Sensor Networks (UWSNs) are an enabling technology for many applications in commercial, military, and scientific domains. In some emergency response applications of UWSN, data dissemination is more important, therefore these applications are handled differently as compared to energy-focused approaches, which is only possible when propagation delay is minimized and packet delivery at surface sinks is assured. Packet delivery underwater is a serious concern because of harsh underwater environments and the dense deployment of nodes, which causes collisions and packet loss. Resultantly, re-transmission causes energy loss and increases end-to-end delay ( D E 2 E ). In this work, we devise a framework for the joint optimization of sink mobility, hold and forward mechanisms, adoptive depth threshold ( d t h ) and data aggregation with pattern matching for reducing nodal propagation delay, maximizing throughput, improving network lifetime, and minimizing energy consumption. To evaluate our technique, we simulate the three-dimensional (3-D) underwater network environment with mobile sink and dense deployments of sensor nodes with varying communication radii. We carry out scalability analysis of the proposed framework in terms of network lifetime, throughput, and packet drop. We also compare our framework to existing techniques, i.e., Mobicast and iAMCTD protocols. We note that adapting varying d t h based on node density in a range of network deployment scenarios results in a reduced number of re-transmissions, good energy conservation, and enhanced throughput. Furthermore, results from extensive simulations show that our proposed framework achieves better performance over existing approaches for real-time delay-intolerant applications.
An Application of the Orthogonal Matching Pursuit Algorithm in Space-Time Adaptive Processing
Authors: Ślesicka Anna , Kawalec Adam
Published: June 2020

The article presents a new space-time adaptive processing (STAP) method for target detection in a heterogeneous and non-stationary environment. In study it was proven that it is possible to estimate the clutter covariance matrix (CCM) in STAP by using the MIMO (Multiple Input Multiple Output) radar geometry model and the orthogonal matching pursuit (OMP) algorithm. For the estimation of spatio-temporal spectrum of clutter and target, a model of joint sparse recovery was established. As a result, clutter suppression and target detection in a heterogeneous environment will be achieved. In addition, the proposed method uses a single snapshot of the radar data cube, which eliminates the need for access to all training cells.
Prediction of Body Weight of a Person Lying on a Smart Mat in Nonrestraint and Unconsciousness Conditions
Authors: Kim Tae-Hwan , Hong Youn-Sik
Published: June 2020

We want to predict body weight while lying in bed for an elderly patient who is unable to move by himself/herself. To this end, we have implemented a prototype system that estimates the body weight of a person lying on a smart mat in nonrestraint and unconsciousness conditions. A total of 128 FSR (force sensing resistor) sensors were placed in a 16 × 8-grid structure on the smart mat. We formulated three methods based on the features to be applied: segmentation, average cumulative sum of pressure, and serialization. All the proposed methods were implemented with four different machine-learning models: regression, deep neural network (DNN), convolutional neural network (CNN), and random forest. We compared their performance using MAE and RMSE as evaluation criteria. From the experimental results, we chose the serialization method with the DNN model as the best model. Despite the limitations of the presence of dead space due to the wide spacing between the sensors and the small dataset, the MAE and the RMSE of the body weight prediction of the proposed method was 4.608 and 5.796, respectively. That is, it showed an average error of ±4.6 kg for the average weight of 72.9 kg.
The First Steps to Develop a Monitoring-Based Method to Support the Sustainable Mosquito Control in an Urban Environment in Hungary
Authors: Kiss Tibor , Leitol Csaba , Márovics Gergely , Zentai Tímea , Baczur Roland , Girán János
Published: June 2020

In Europe, several exotic Aedes species, such as Aedes albopictus, Aedes eagypti, Aedes japonicas and Aedes koreicus, have become established. Mosquito-borne infection has also become a rising public health issue in Europe. This study aims to present the results of the first Hungarian systematic mosquito monitoring (SMM) operating in an urban environment in the city of Pécs. It also explains the implementation of a targeted mosquito control by the development of a mosquito map with the SMM approach, thus contributing to a reduction of the risks of mosquito-borne diseases. The mosquito trapping started in 2015, and the traps were Center for Disease Control (CDC) equipment. Based on the data of the SMM, an urban mosquito data set was developed. It consisted of the data of 441 trappings, and the data were statistically analyzed. The results show that three influencing factors impacted mosquito population: distance from running water, built-up density and average temperature had a causal impact on the average number of mosquitoes of an urban area. Each of these factors showed direct impact, and the impact intensified with the combination of the three factors. On that basis, it was made clear which areas of the city mosquito control activity should be focused. Areas of the city where interventions of lower intensity may be necessary compared to the intensity of the earlier mosquito control measures could also be determined. Compared to the previous practice, in which the entire city was involved in intensive mosquito control, now the intensive larviciding is advised to be applied in 42.1% of the total residential areas of the city. Thus, mosquito control of lower intensity could also be sufficient in the remaining 57.9% of the city area. This resource reallocation based on planning can boost the efficiency of the control and lead to a positive change towards sustainability regarding reduced pressure on the environment and reduced expenses of protection.
The Function of Transition Brokers in the Regional Governance of Implementing Circular Economy—A Comparative Case Study of Six Dutch Regions
Authors: Cramer Jacqueline M.
Published: June 2020

This paper addresses the question of which function systemic intermediaries (here called ‘transition brokers’) can fulfil in the regional governance of implementing a circular economy (CE). Empirical research on this issue is scarce. The conclusion, based on a comparative case study of six Dutch regions, is that transition brokers fulfil the function of system orchestration. They can enhance processes of change, build alliances, help create the necessary preconditions, and develop impactful circular initiatives from a neutral standpoint. In a multi-stakeholder setting, transition brokers fulfil a variety of roles, depending on time period, content, and context. Executing these roles requires a number of specific competencies, varying from being entrepreneurially minded to daring to leave one’s comfort zone and being able to get the idea of CE accepted in a variety of businesses and organisations. From interviews held with key transition brokers in the six regions, it transpired that there is a clear division of labour between transition brokers vis-à-vis other key actors, among which the local government is included. These findings allow the design of a new model of regional governance in implementing CE from a system level perspective. It is recommended to perform similar case studies in other countries to generalise the results presented here.