bluuebunny/crossref_metadata_2025 huggingface dataset:
Reflectance Spectroscopy for Non-Destructive Measurement and Genetic Analysis of Amounts and Types of Epicuticular Waxes on Onion Leaves
Authors: Munaiz Eduardo D. , Townsend Philip A. , Havey Michael J.
Published: July 2020

Epicuticular waxes on the surface of plant leaves are important for the tolerance to abiotic stresses and plant–parasite interactions. In the onion (Allium cepa L.), the variation for the amounts and types of epicuticular waxes is significantly associated with less feeding damage by the insect Thrips tabaci (thrips). Epicuticular wax profiles are measured using used gas chromatography mass spectrometry (GCMS), which is a labor intensive and relatively expensive approach. Biochemical spectroscopy is a non-destructive tool for measurement and analysis of physiological and chemical features of plants. This study used GCMS and full-range biochemical spectroscopy to characterize epicuticular waxes on seven onion accessions with visually glossy (low wax), semi-glossy (intermediate wax), or waxy (copious wax) foliage, as well as a segregating family from the cross of glossy and waxy onions. In agreement with previous studies, GCMS revealed that the three main waxes on the leaves of a wild type waxy onion were the ketone hentriacontanone-16 (H16) and fatty alcohols octacosanol-1 (Oct) and triacontanol-1 (Tri). The glossy cultivar “Odourless Greenleaf” had a unique phenotype with essentially no H16 and Tri and higher amounts of Oct and the fatty alcohol hexacosanol-1 (Hex). Hyperspectral reflectance profiles were measured on leaves of the onion accessions and segregating family, and partial least-squares regression (PLSR) was utilized to generate a spectral coefficient for every wavelength and prediction models for the amounts of the three major wax components. PLSR predictions were robust with independent validation coefficients of determination at 0.72, 0.70, and 0.42 for H16, Oct, and Tri, respectively. The predicted amounts of H16, Oct, and Tri are the result of an additive effect of multiple spectral features of different intensities. The variation of reflectance for H16, Oct, and Tri revealed unique spectral features at 2259 nm, 645 nm, and 730 nm, respectively. Reflectance spectroscopy successfully revealed a major quantitative trait locus (QTL) for amounts of H16, Oct, and Tri in the segregating family, agreeing with previous genetic studies. This study demonstrates that hyperspectral signatures can be used for non-destructive measurement of major waxes on onion leaves as a basis for rapid plant assessment in support of developing thrips-resistant onions.
Equilibria in Aqueous Cobalt(II)—Reduced Schiff Base N-(2-hydroxybenzyl)alanine System: Chemical Characterization, Kinetic Analysis, Antimicrobial and Cytotoxic Properties
Authors: Woźniczka Magdalena , Sutradhar Manas , Pombeiro Armando J. L. , Świątek Mirosława , Pająk Marek , Gądek-Sobczyńska Joanna , Chmiela Magdalena , Gonciarz Weronika , Pasternak Beata , Kufelnicki Aleksander
Published: July 2020

The present study describes the coordination properties of a reduced Schiff base, N-(2-hydroxybenzyl)alanine, towards cobalt(II) using potentiometric as well as spectroscopic (UV-Vis and ESI-MS) methods. The results indicate the formation of six mononuclear complexes showing high stability in aqueous solution. Coordination occurs in the {O−phenolic,N,O−carboxyl} and {N,O−carboxyl} chelation modes, depending on the degree of ligand deprotonation. Examination of the complexation equilibria at pH ca 7, which is important from a biological point of view, allowed to identify two species: [CoL] and [CoL2H]−. The kinetic analysis showed a structural change of those cobalt(II) complexes from octahedral to tetrahedral in accordance with a first-order time relationship. The antimicrobial properties of N-(2-hydroxybenzyl)alanine, cobalt(II) nitrate and of the Co(II) – ligand complexes were determined against Gram-positive bacteria (Enterococcus faecalis, Staphylococcus aureus, Staphylococcus epidermidis), Gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli, Helicobacter pylori) and a fungal strain (Candida). The results indicate that the complexes are more active for more strains than the ligand alone. Nevertheless, the complexes induce a higher decrease in the metabolic activity of cells but without damage to nuclei. Tetrahedral structures show stronger anti-cellular toxicity than octahedral complexes, which is most likely due to the higher accessibility of the cobalt(II) center.
HFIP-Promoted Synthesis of Substituted Tetrahydrofurans by Reaction of Epoxides with Electron-Rich Alkenes
Authors: Llopis Natalia , Baeza Alejandro
Published: July 2020

In the present work, the employment of fluorinated alcohols, specifically 1,1,1,3,3,3-hexafluoroisopropanol (HFIP), as solvent and promoter of the catalyst-free synthesis of substituted tetrahydrofuranes through the addition of electron-rich alkenes to epoxydes is described. The unique properties of this fluorinated alcohol, which is very different from their non-fluorinated analogs, allows carrying out this new straightforward protocol under smooth reaction conditions affording the corresponding adducts in moderate yields in the majority of cases. Remarkably, this methodology has allowed the synthesis of new tetrahydrofuran-based spiro compounds as well as tetrahydrofurobenzofuran derivatives. The scope and limitations of the process are also discussed. Mechanistic studies were also performed pointing towards a purely ionic or a SN2-type process depending on the nucleophilicity of the alkene employed.
Bioactive Chemical Composition of Cannabis Extracts and Cannabinoid Receptors
Authors: Yang Yi , Vyawahare Rupali , Lewis-Bakker Melissa , Clarke Hance A. , Wong Albert H. C. , Kotra Lakshmi P.
Published: July 2020

Cannabis is widely used as a therapeutic drug, especially by patients suffering from psychiatric and neurodegenerative diseases. However, the complex interplay between phytocannabinoids and their targets in the human receptome remains largely a mystery, and there have been few investigations into the relationship between the chemical composition of medical cannabis and the corresponding biological activity. In this study, we investigated 59 cannabis samples used by patients for medical reasons. The samples were subjected to extraction (microwave and supercritical carbon dioxide) and chemical analyses, and the resulting extracts were assayed in vitro using the CB1 and CB2 receptors. Using a partial least squares regression analysis, the chemical compositions of the extracts were then correlated to their corresponding cannabinoid receptor activities, thus generating predictive models that describe the receptor potency as a function of major phytocannabinoid content. Using the current dataset, meaningful models for CB1 and CB2 receptor agonism were obtained, and these reveal the insignificant relationships between the major phytocannabinoid content and receptor affinity for CB1 but good correlations between the two at CB2 receptors. These results also explain the anomalies between the receptor activities of pure phytocannabinoids and cannabis extracts. Furthermore, the models for CB1 and CB2 agonism in cannabis extracts predict the cannabinoid receptor activities of individual phytocannabinoids with reasonable accuracy. Here for the first time, we disclose a method to predict the relationship between the chemical composition, including phytocannabinoids, of cannabis extracts and cannabinoid receptor responses.
Quantitative Microdialysis: Experimental Protocol and Software for Small Molecule Protein Affinity Determination and for Exclusion of Compounds with Poor Physicochemical Properties
Authors: Shave Steven , Pham Nhan T. , Śmieja Connor B. , Auer Manfred
Published: July 2020

Quantitative microdialysis is a traditional biophysical affinity determination technique. In the development of the detailed experimental protocol presented, we used commercially available equipment, rapid equilibrium dialysis (RED) devices (ThermoFisher Scientific), which means that it is open to most laboratories. The target protein and test compound are incubated in a chamber partitioned to allow only small molecules to transition to a larger reservoir chamber, then reversed-phase high performance liquid chromatography (RP-HPLC) or liquid chromatography–mass spectrometry (LC–MS) is used to determine the abundance of compound in each chamber. A higher compound concentration measured in the chamber that contains the target protein indicates binding. As a novel, and differentiating contribution, we present a protocol for mathematical analysis of experimental data. We provide the equations and the software to yield dissociation constants for the test compound-target protein complex up to 0.5 mM KD, and we quantitatively discuss the limitations of affinities in relation to measured compound concentrations.
The Association between Seafood Intake and Fecundability: Analysis from Two Prospective Studies
Authors: Wise Lauren A. , Willis Sydney K. , Mikkelsen Ellen M. , Wesselink Amelia K. , Sørensen Henrik Toft , Rothman Kenneth J. , Tucker Katherine L. , Trolle Ellen , Vinceti Marco , Hatch Elizabeth E.
Published: July 2020

Background: Seafood is an important source of omega-3 fatty acids, which have been associated with improved oocyte quality and embryo morphology in some studies. However, seafood is also a source of persistent organic pollutants and heavy metals, which may adversely affect fecundity. Previous studies of seafood intake and fecundity have generated inconsistent results. Methods: In two prospective cohort studies of 7836 female pregnancy planners from Denmark (Snart Foraeldre, n = 2709) and North America (PRESTO, n = 5127), we evaluated the association of dietary intake of total seafood and marine-sourced long-chain omega-3 fatty acids (eicosapentaenoic acid, docosahexaenoic acid, and docosapentaenoic acid) with fecundability. Participants completed a baseline questionnaire on sociodemographics, behavioral factors, anthropometrics, and medical history, and a food frequency questionnaire. Pregnancy status was updated bimonthly for up to 12 months or until reported conception. We estimated fecundability ratios (FRs) and 95% confidence intervals (CIs) using proportional probabilities regression models, adjusted for energy intake and other potential confounders. We restricted analyses to women with ≤6 menstrual cycles of attempt time at enrollment. Results: Intake of total seafood or marine-sourced long-chain omega-3 fatty acids was not appreciably associated with fecundability in either cohort (≥200 vs. <50 g/week total seafood: FR = 0.94, 95% CI: 0.79–1.10 in Snart Foraeldre; FR = 1.00, 95% CI: 0.90–1.13 in PRESTO; marine fatty acids: ≥90th vs. <25th percentile: FR = 1.00, 95% CI: 0.85–1.18 in Snart Foraeldre; FR = 0.97, 95% CI: 0.86–1.09 in PRESTO). In PRESTO, where we collected additional data on seafood preparation, we observed an inverse association between fecundability and fried shellfish (≥10 g/week vs. none: FR = 0.77, 95% CI: 0.61–0.98), but not unfried shellfish (≥20 g/week vs. none: FR = 0.98, 95% CI: 0.89–1.07); in Snart Foraeldre, there was no association with total shellfish intake. Conclusions: We found little association between seafood intake and fecundability overall, but greater intake of fried shellfish was associated with reduced fecundability among North American participants.
How Does Time Use Differ between Individuals Who Do More versus Less Foodwork? A Compositional Data Analysis of Time Use in the United Kingdom Time Use Survey 2014–2015
Authors: Clifford Astbury Chloe , Foley Louise , Penney Tarra L. , Adams Jean
Published: July 2020

Background: Increased time spent on home food preparation is associated with higher diet quality, but a lack of time is often reported as a barrier to this practice. We compared time use in individuals who do more versus less foodwork (tasks required to feed ourselves and our households, including home food preparation). Methods: Cross-sectional analysis of the UK Time Use Survey 2014–15, participants aged 16+ (N = 6143). Time use over 24 h was attributed to seven compositional parts: personal care; sleep; eating; physical activity; leisure screen time; work (paid and unpaid); and socialising and hobbies. Participants were categorised as doing no, ‘some’ (<70 min), or ‘more’ foodwork (≥70 min). We used compositional data analysis to test whether time-use composition varied between these participant groups, determine which of the parts varied between groups, and test for differences across population subgroups. Results: Participants who spent more time on foodwork spent less time on sleep, eating, and personal care and more time on work. Women who did more foodwork spent less time on personal care, socialising, and hobbies, which was not the case for men. Conclusion: Those who seek to encourage home food preparation should be aware of the associations between foodwork and other activities and design their interventions to guard against unintended consequences.
Sulforaphane Diminishes the Formation of Mammary Tumors in Rats Exposed to 17β-Estradiol
Authors: Palliyaguru Dushani L. , Yang Li , Chartoumpekis Dionysios V. , Wendell Stacy G. , Fazzari Marco , Skoko John J. , Liao Yong , Oesterreich Steffi , Michalopoulos George K. , Kensler Thomas W.
Published: July 2020

Elevated levels of estrogen are a risk factor for breast cancer. In addition to inducing DNA damage, estrogens can enhance cell proliferation as well as modulate fatty acid metabolism that collectively contributes to mammary tumorigenesis. Sulforaphane (SFN) is an isothiocyanate derived from broccoli that is currently under evaluation in multiple clinical trials for prevention of several diseases, including cancer. Previous studies showed that SFN suppressed DNA damage and lipogenesis pathways. Therefore, we hypothesized that administering SFN to animals that are co-exposed to 17β-estradiol (E2) would prevent mammary tumor formation. In our study, 4–6 week old female August Copenhagen Irish rats were implanted with slow-release E2 pellets (3 mg x 3 times) and gavaged 3x/week with either vehicle or 100 μmol/kg SFN for 56 weeks. SFN-treated rats were protected significantly against mammary tumor formation compared to vehicle controls. Mammary glands of SFN-treated rats showed decreased DNA damage while serum free fatty acids and triglyceride species were 1.5 to 2-fold lower in SFN-treated rats. Further characterization also showed that SFN diminished expression of enzymes involved in mammary gland lipogenesis. This study indicated that SFN protects against breast cancer development through multiple potential mechanisms in a clinically relevant hormonal carcinogenesis model.
Accurate and Rapid Identification of Longan Arillus and Litchi Semen by a Multiplex PCR Assay
Authors: Kim Wook Jin , Yang Sungyu , Choi Goya , Park Inkyu , Noh Pureum , Kim Min Jee , Moon Byeong Cheol
Published: July 2020

Dimocarpus longan, Litchi chinensis, and Nephelium lappaceum are commercially valuable subtropical and tropical fruits of the Sapindaceae family. Arillus and seeds of the three species have very similar morphologies; however, the arillus of D. longan is used as the herbal medicine Longan Arillus and seeds of L. chinensis are used as Litchi Semen in Korean and Chinese pharmacopoeias. The adulteration of herbal medicines with inauthentic species, including the use of Aril and seed fractions acquired from a single species for two herbal medicines (e.g., Longan Arillus and Litchi Semen), is often driven by economic motives. DNA markers are a tool for the detection of adulterants in commercial products. To establish rapid and reliable assays for the genetic identification of authentic Longan Arillus and Litchi Semen, we developed DNA markers with high specificity and sensitivity based on internal transcribed spacer (ITS) sequences. The newly developed DNA markers and multiplex PCR assay may contribute to efforts to protect against adulteration, quality control, and the standardization of herbal medicines.
Medicinal Properties of Lilium candidum L. and Its Phytochemicals
Authors: Zaccai Michele , Yarmolinsky Ludmila , Khalfin Boris , Budovsky Arie , Gorelick Jonathan , Dahan Arik , Ben-Shabat Shimon
Published: July 2020

Lilium candidum L., known as Madonna, meadow, or white lily, is a bulbous plant from the Liliaceae family, originating in the Middle East. L. candidum has been abundantly used in folk medicine since ancient times to relieve a variety of ailments, including age-related diseases, burns, ulcers, and coughs. The aim of this article is to investigate the anti-inflammatory and anti-diabetic activities of L. candidum extracts and its active phytochemicals. Some active volatile phytochemicals were identified using gas chromatography–mass spectrometry (GC-MS) analysis. Significant (p < 0.001) anti-diabetic properties of the extracts kaempferol, linalool, citronellal, and humulene were demonstrated by an elevation in glucose uptake by adipocytes. The significant (p < 0.01) effect of the plant extracts kaempferol, citronellal, and humulene on the secretion of pro-inflammatory cytokines interleukin 6 (IL-6) and interleukin 8 (IL-8) was demonstrated using enzyme-linked immunosorbent assay. Altogether, L. candidum and its rich collection of phytochemicals hold promising medicinal potential, and further investigations of its therapeutic prospects are encouraged.
A Review on Applications and Uses of Thymus in the Food Industry
Authors: Nieto Gema
Published: July 2020

Thyme is one of the most important medicinal plants because of its ethnopharmacological relevance and high content of bioactive compounds. This review focuses particularly on thyme as an alternative natural antioxidant and antimicrobial with potential use in the food industry. This is in line with the preferences of the current consumer, who demands healthier and more natural products. Different studies have concluded that the use of thyme increases stability and reduces lipid oxidation during the shelf-life period of foods (meat, meat products, milk, fish or fish products), which makes thyme a promising source of natural additives. Despite these findings, the use of Thymus extracts or essential oils as natural additives in foods is reduced in comparison with other natural preservative extracts. This review provides an overview of the most important information on the positive effect of the bioactive compounds of thyme and its uses as a preservative in foods, taking into account its origin (from plants, plant extracts or essential oils).
Arbuscular Mycorrhizal Symbiosis Enhances Photosynthesis in the Medicinal Herb Salvia fruticosa by Improving Photosystem II Photochemistry
Authors: Moustakas Michael , Bayçu Gülriz , Sperdouli Ilektra , Eroğlu Hilal , Eleftheriou Eleftherios P.
Published: July 2020

We investigated the influence of Salvia fruticosa colonization by the arbuscular mycorrhizal fungi (AMF) Rhizophagus irregularis on photosynthetic function by using chlorophyll fluorescence imaging analysis to evaluate the light energy use in photosystem II (PSII) of inoculated and non-inoculated plants. We observed that inoculated plants used significantly higher absorbed energy in photochemistry (ΦPSII) than non-inoculated and exhibited significant lower excess excitation energy (EXC). However, the increased ΦPSII in inoculated plants did not result in a reduced non-regulated energy loss in PSII (ΦNO), suggesting the same singlet oxygen (1O2) formation between inoculated and non-inoculated plants. The increased ΦPSII in inoculated plants was due to an increased efficiency of open PSII centers to utilize the absorbed light (Fv’/Fm’) due to a decreased non-photochemical quenching (NPQ) since there was no difference in the fraction of open reaction centers (qp). The decreased NPQ in inoculated plants resulted in an increased electron-transport rate (ETR) compared to non-inoculated. Yet, inoculated plants exhibited a higher efficiency of the water-splitting complex on the donor side of PSII as revealed by the increased Fv/Fo ratio. A spatial heterogeneity between the leaf tip and the leaf base for the parameters ΦPSII and ΦNPQ was observed in both inoculated and non-inoculated plants, reflecting different developmental zones. Overall, our findings suggest that the increased ETR of inoculated S. fruticosa contributes to increased photosynthetic performance, providing growth advantages to inoculated plants by increasing their aboveground biomass, mainly by increasing leaf biomass.
Development of Biodegradable Cosmetic Patch Using a Polylactic Acid/Phycocyanin–Alginate Composite
Authors: Adli Sarah Amalina , Ali Fathilah , Azmi Azlin Suhaida , Anuar Hazleen , Nasir Nur Aimi Mohd , Hasham Rosnani , Idris Mohamad Khairul Hafiz
Published: July 2020

The usage of non-degradable polymer as the main matrix for a cosmetic patch raises concern, as it can cause environmental pollution when discarded in landfill. Thus, biodegradable polylactic acid (PLA) was chosen in this study, as PLA has non-toxic properties and similar mechanical properties to conventional plastic materials. An active ingredient in a cosmetic patch serves the purpose of providing beneficial ingredients to the skin; therefore, phycocyanin, an extract from spirulina, was chosen, as it possesses antioxidant and anti-inflammatory properties. Alginate was also incorporated with the phycocyanin for fabrication onto the PLA matrix. A preliminary study was first carried out to identify the antioxidant properties and cytotoxic effect of the phycocyanin on skin cells. It was observed that phycocyanin had no cytotoxic effect on the skin and showed good antioxidant activity. PLA/phycocyanin–alginate composite was fabricated using a solvent casting method, and optimization of preparation conditions (phycocyanin/alginate ratio, stirring time, and temperature) were carried out using the one-factor-at-a-time (OFAT) method with responses of elongation at break and releasing properties. Attenuated total reflectance (ATR)–FTIR analysis was also conducted to further analyze the functional group of the composites. Surface morphologies were observed for samples before and after the releasing test. From the analyses conducted, PLA/phycocyanin–alginate composite prepared at a phycocyanin/alginate ratio of 40/60 for 20 h at 20 °C gave the best properties in terms of flexibility of film and releasing properties of phycocyanin.
Dyeing and Antibacterial Properties of Chemically Recycled PET Thermal-Bonded Nonwovens Dyed with Terminalia chebula Dye
Authors: Lee Joo Hyung , Jung Jong Sun , Kim Seong Hun
Published: July 2020

Waste recycling is a necessary step for environmental conservation. To this end, polyester can be easily collected and recycled into end products. To promote the use of recycled polyester, it is important to expand its range of applications. We earlier reported the fabrication of recycled polyester thermal-bonded nonwovens. In this study, recycled nonwoven fabrics were dyed with Terminalia chebula dye without the use of additional mordants. To optimize the dyeing conditions, the dyeing time, dyeing temperature, and liquor concentration were varied, and the color strength, color changes, fastness properties, thermal stability, and morphology were evaluated. Further, the antibacterial activity of the dyed nonwoven was also estimated. T. chebula dyed the colored recycled rapid melting PET fiber (R-RM) nonwoven brown via the dyeing process, and the dyeablity was improved by increasing the dyeing temperature, time, and liquor concentration. The rubbing and sweat fastness properties were found to be excellent. T. chebula dye imparted efficient antibacterial properties to the R-RM nonwovens against Staphylococcus aureus and Klebsiella pneumonia. The results obtained in this study are expected to broaden the range of natural dyed recycled polyester fabric applications.
Tribological and Mechanical Behavior of Graphite Composites of Polytetrafluoroethylene (PTFE) Irradiated by the Electron Beam
Authors: Barylski Adrian , Swinarew Andrzej S. , Aniołek Krzysztof , Kaptacz Sławomir , Gabor Jadwiga , Stanula Arkadiusz , Waśkiewicz Zbigniew , Knechtle Beat
Published: July 2020

This research investigated the effect of irradiation with an electron beam energy of 10 MeV in doses of 26–156 kGy on polytetrafluoroethylene (PTFE) with a 15% and 20% graphite additive. The research has shown that mechanical (compression strength, hardness, and Young’s modulus) and sclerometric (coefficient of wear micromechanism and coefficient of resistance to wear) properties improve and tribological wear decreases as graphite content increases. Electron beam irradiation increases the degree of crystallinity of both materials to a similar extent. However significant differences in the improvement of all examined properties have been demonstrated for PTFE with higher (20%) graphite content subjected to the electron beam irradiation. This polymer is characterized by higher hardness and Young’s modulus, reduced susceptibility to permanent deformation, higher elasticity, compression strength, and above all, a nearly 30% reduction in tribological wear compared to PTFE with a 15% graphite additive. The most advantageous properties can be obtained for both of the examined composites after absorbing a dose of 104 kGy. The obtained results hold promise for the improvement of the operational life of friction couples which do not require lubrication, used for example in air compressors and engines, and for the possibility of application of these modified polymers. In particular PTFE with 20% graphite content, in the nuclear and space industry.
Bioinspired Hydrogel Coating Based on Methacryloyl Gelatin Bioactivates Polypropylene Meshes for Abdominal Wall Repair
Authors: Serafim Andrada , Cecoltan Sergiu , Olăreț Elena , Dragusin Diana-Maria , Vasile Eugeniu , Popescu Valentin , Manolescu Mastalier Bogdan Stelian , Iovu Horia , Stancu Izabela-Cristina
Published: July 2020

Considering the potential of hydrogels to mimic the cellular microenvironment, methacryloyl gelatin (GelMA) and methacryloyl mucin (MuMA) were selected and compared as bioinspired coatings for commercially available polypropylene (PP) meshes for ventral hernia repair. Thin, elastic hydrated hydrogel layers were obtained through network-forming photo-polymerization, after immobilization of derivatives on the surface of the PP fibers. Fourier transform infrared spectroscopy (FTIR) proved the successful coating while the surface morphology and homogeneity were investigated by scanning electron microscopy (SEM) and micro-computed tomography (micro-CT). The stability of the hydrogel layers was evaluated through biodynamic tests performed on the coated meshes for seven days, followed by inspection of surface morphology through SEM and micro-CT. Taking into account that platelet-rich plasma (PRP) may improve healing due to its high concentration of growth factors, this extract was used as pre-treatment for the hydrogel coating to additionally stimulate cell interactions. The performed advanced characterization proved that GelMA and MuMA coatings can modulate fibroblasts response on PP meshes, either as such or supplemented with PRP extract as a blood-derived bioactivator. GelMA supported the best cellular response. These findings may extend the applicative potential of functionalized gelatin opening a new path on the research and engineering of a new generation of bioactive meshes.
Insoluble Polymers in Solid Dispersions for Improving Bioavailability of Poorly Water-Soluble Drugs
Authors: Tran Thao T.D. , Tran Phuong H.L.
Published: July 2020

In recent decades, solid dispersions have been demonstrated as an effective approach for improving the bioavailability of poorly water-soluble drugs, as have solid dispersion techniques that include the application of nanotechnology. Many studies have reported on the ability to change drug crystallinity and molecular interactions to enhance the dissolution rate of solid dispersions using hydrophilic carriers. However, numerous studies have indicated that insoluble carriers are also promising excipients in solid dispersions. In this report, an overview of solid dispersion strategies involving insoluble carriers has been provided. In addition to the role of solubility and dissolution enhancement, the perspectives of the use of these polymers in controlled release solid dispersions have been classified and discussed. Moreover, the compatibility between methods and carriers and between drug and carrier is mentioned. In general, this report on solid dispersions using insoluble carriers could provide a specific approach and/or a selection of these polymers for further formulation development and clinical applications.
Influence of Interactions among Polymeric Components of Automobile Shredder Residue on the Pyrolysis Temperature and Characterization of Pyrolytic Products
Authors: Yang Bin , Chen Ming
Published: July 2020

Pyrolysis and gasification have gradually become the main means to dispose of automobile shredder residue (ASR), since these methods can reduce the volume and quality of landfill with lower cost and energy recovery can be conducted simultaneously. As the ASR pyrolysis process is integrated, the results of pyrolysis reactions of organic components and the interaction among polymeric components can be clarified by co-pyrolysis thermogravimetric experiments. The results show that the decomposition mechanisms of textiles and foam are markedly changed by plastic in the co-pyrolysis process, but the effect is not large for rubber and leather. This effect is mainly reflected in the pyrolysis temperature and pyrolysis rate. The pyrolytic trend and conversion curve shape of the studied ASR can be predicted by the main polymeric components with a parallel superposition model. The pyrolytic product yields and characterizations of gaseous products were analyzed in laboratory-scale non-isothermal pyrolysis experiments at finished temperatures of 500 °C, 600 °C, and 700 °C. The results prove that the yields of pyrolytic gas products are determined by the thermal decomposition of organic substances in the ASR and final temperature.
Establishment of Complex Modulus Master Curves Based on Generalized Sigmoidal Model for Freeze–Thaw Resistance Evaluation of Basalt Fiber-Modified Asphalt Mixtures
Authors: Tan Guojin , Wang Wensheng , Cheng Yongchun , Wang Yong , Zhu Zhiqing
Published: July 2020

This study aims to study the freeze–thaw (F–T) resistance of asphalt mixture incorporating styrene–butadiene–styrene (SBS) polymer and basalt fiber by using the established complex master curves of the generalized Sigmoidal model. Asphalt mixture samples incorporating styrene–butadiene–styrene (SBS) polymer and basalt fiber were manufactured following the Superpave gyratory compaction (SGC) method and coring as well as sawing. After 0–21 F–T cycles processing, a complex modulus test asphalt mixture specimen was performed to evaluate the influence of the F–T cycle. Besides, according to the time–temperature superposition principle, the master curves of a complex modulus were constructed to reflect the dynamic mechanical response in an extended range of reduced frequency at an arbitrary temperature. The results indicated that the elastic and viscous portions of asphalt mixture incorporating SBS and basalt fiber have decreased overall. It could be observed from the dynamic modulus ratio that the dynamic modulus ratios of specimens were more affected by the F–T cycle at low frequency or high temperature. Thus, in the process of asphalt pavement design and maintenance, attention should be paid to seasonal frozen asphalt pavement under low frequency and high temperature.
Development and Characterization of Polyester and Acrylate-Based Composites with Hydroxyapatite and Halloysite Nanotubes for Medical Applications
Authors: Torres Elena , Dominguez-Candela Ivan , Castello-Palacios Sergio , Vallés-Lluch Anna , Fombuena Vicent
Published: July 2020

We aimed to study the distribution of hydroxyapatite (HA) and halloysite nanotubes (HNTs) as fillers and their influence on the hydrophobic character of conventional polymers used in the biomedical field. The hydrophobic polyester poly (ε-caprolactone) (PCL) was blended with its more hydrophilic counterpart poly (lactic acid) (PLA) and the hydrophilic acrylate poly (2-hydroxyethyl methacrylate) (PHEMA) was analogously compared to poly (ethyl methacrylate) (PEMA) and its copolymer. The addition of HA and HNTs clearly improve surface wettability in neat samples (PCL and PHEMA), but not that of the corresponding binary blends. Energy-dispersive X-ray spectroscopy mapping analyses show a homogenous distribution of HA with appropriate Ca/P ratios between 1.3 and 2, even on samples that were incubated for seven days in simulated body fluid, with the exception of PHEMA, which is excessively hydrophilic to promote the deposition of salts on its surface. HNTs promote large aggregates on more hydrophilic polymers. The degradation process of the biodegradable polyester PCL blended with PLA, and the addition of HA and HNTs, provide hydrophilic units and decrease the overall crystallinity of PCL. Consequently, after 12 weeks of incubation in phosphate buffered saline the mass loss increases up to 48% and mechanical properties decrease above 60% compared with the PCL/PLA blend.
Improving the Sensory Properties of Layered Phospholipid-Graphene Films Due to the Curvature of Graphene Layers
Authors: Slepchenkov Michael M. , Glukhova Olga E.
Published: July 2020

This article is devoted to the in silico study of the sensory properties of mono- and bilayer phospholipid-graphene films with planar and curved graphene sheets. The DPPC (dipalmitoylphosphatidylcholine) molecules are considered as phospholipid structures. These molecules are part of lipid bilayers, liposomes and cell membranes. To find a way to improve the sensory properties of phospholipid-graphene films, we studied the effect of the curvature of the graphene sheet on the charge transfer and electrical conductivity of the films. The distribution of the electron charge density over the film atoms was calculated using the self-consistent-charge density-functional tight-binding method (SCC-DFTB). The calculation of the current through phospholipid-graphene films was carried out within the framework of the Landauer–Buttiker formalism using the Keldysh nonequilibrium Green function technique. As a result of the calculations, the optimal configuration of the arrangement of DPPC molecules between two graphene layers was established. This configuration provides the maximum possible increase in current to 1 μA at low voltages of ~0.2 V and is achieved for curved graphene with a radius of curvature of ~2.7 nm at individual points of graphene atomic network.
A Call for a More Efficient Submission Process
Authors: Oh Hans
Published: July 2020

This commentary argues that the manuscript submission process is needlessly complicated and bothersome and would benefit from user experience research to simplify the author guidelines and to add design features that minimize mistakes.
Catholic Family Ties: Sustaining and Supporting HIV-Positive Canadian Gay Men’s Faith, Mental Health, and Wellbeing
Authors: Liboro Renato M.
Published: July 2020

Research has documented that sexual minorities and people living with HIV/AIDS have successfully used religious coping to help them overcome life challenges related to their sexual orientation and HIV status, including religious struggles surrounding their faith brought about by stigma and discrimination that have historically been promoted by organized religion. Research has also documented how sexual minorities and people living with HIV/AIDS have utilized family support as a vital resource for effectively coping with life challenges associated with homophobia, heterosexism, and HIV stigma, which have historically been perpetuated in certain family and faith dynamics. The aim of the community-engaged, qualitative study described in this article was to examine the synergistic effects of religious coping and family support, particularly in the context of Catholic family ties, as a unified mechanism for supporting HIV-positive gay men in the face of religious struggles and other life challenges. Confidential, semi-structured interviews were conducted with nine HIV-positive, gay men from the Greater Toronto Area of Ontario, Canada, to obtain their perspectives on how and why their Catholic family ties have helped support them through their religious struggles and other life challenges. Utilizing a modified Grounded Theory approach, interview data were collected and analyzed until data saturation was achieved. The findings and lessons learned from the study’s analysis are discussed in this article, which elaborates on the unique synergy of religious coping and family support as interconnected mechanisms that could be of significant value for supporting HIV-positive gay men experiencing religious struggles and other life challenges.
Impacts of Drought on Vegetation Assessed by Vegetation Indices and Meteorological Factors in Afghanistan
Authors: Rousta Iman , Olafsson Haraldur , Moniruzzaman Md , Zhang Hao , Liou Yuei-An , Mushore Terence Darlington , Gupta Amitesh
Published: July 2020

Drought has severe impacts on human society and ecosystems. In this study, we used data acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS) and Tropical Rainfall Measuring Mission (TRMM) sensors to examine the drought effects on vegetation in Afghanistan from 2001 to 2018. The MODIS data included the 16-day 250-m composites of the Normalized Difference Vegetation Index (NDVI) and the Vegetation Condition Index (VCI) with Land Surface Temperature (LST) images with 1 km resolution. The TRMM data were monthly rainfalls with 0.1-degree resolution. The relationship between drought and index-defined vegetation variation was examined by using time series, regression analysis, and anomaly calculation. The results showed that the vegetation coverage for the whole country, reaching the lowest levels of 6.2% and 5.5% were observed in drought years 2001 and 2008, respectively. However, there is a huge inter-regional variation in vegetation coverage in the study period with a significant rising trend in Helmand Watershed with R = 0.66 (p value = 0.05). Based on VCI for the same two years (2001 and 2008), 84% and 72% of the country were subject to drought conditions, respectively. Coherently, TRMM data confirm that 2001 and 2008 were the least rainfall years of 108 and 251 mm, respectively. On the other hand, years 2009 and 2010 were registered with the largest vegetation coverage of 16.3% mainly due to lower annual LST than average LST of 14 degrees and partially due to their slightly higher annual rainfalls of 378 and 425 mm, respectively, than the historical average of 327 mm. Based on the derived VCI, 28% and 21% of the study area experienced drought conditions in 2009 and 2010, respectively. It is also found that correlations are relatively high between NDVI and VCI (r = 0.77, p = 0.0002), but slightly lower between NDVI and precipitation (r = 0.51, p = 0.03). In addition, LST played a key role in influencing the value of NDVI. However, both LST and precipitation must be considered together in order to properly capture the correlation between drought and NDVI.
A New Approach for Understanding Urban Microclimate by Integrating Complementary Predictors at Different Scales in Regression and Machine Learning Models
Authors: Alonso Lucille , Renard Florent
Published: July 2020

Climate change is a major contemporary phenomenon with multiple consequences. In urban areas, it exacerbates the urban heat island phenomenon. It impacts the health of the inhabitants and the sensation of thermal discomfort felt in urban areas. Thus, it is necessary to estimate as well as possible the air temperature at any point of a territory, in particular in view of the ongoing rationalization of the network of fixed meteorological stations of Météo-France. Understanding the air temperature is increasingly in demand to input quantitative models related to a wide range of fields, such as hydrology, ecology, or climate change studies. This study thus proposes to model air temperature, measured during four mobile campaigns carried out during the summer months, between 2016 and 2019, in Lyon (France), in clear sky weather, using regression models based on 33 explanatory variables from traditionally used data, data from remote sensing by LiDAR (Light Detection and Ranging), or Landsat 8 satellite acquisition. Three types of statistical regression were experimented: partial least square regression, multiple linear regression, and a machine learning method, the random forest regression. For example, for the day of 30 August 2016, multiple linear regression explained 89% of the variance for the study days, with a root mean square error (RMSE) of only 0.23 °C. Variables such as surface temperature, Normalized Difference Vegetation Index (NDVI), and Modified Normalized Difference Water Index (MNDWI) have a strong impact on the estimation model. This study contributes to the emergence of urban cooling systems. The solutions available vary. For example, they may include increasing the proportion of vegetation on the ground, facades, or roofs, increasing the number of basins and water bodies to promote urban cooling, choosing water-retaining materials, humidifying the pavement, increasing the number of public fountains and foggers, or creating shade with stretched canvas.
Detecting and Assessing Nondominant Farmland Area with Long-Term MODIS Time Series Images
Authors: Yu Shengnan , Zhang Xiaokang , Zhang Xinle , Liu Huanjun , Qi Jiaguo , Sun Yankun
Published: July 2020

While most land use and land cover (LULC) studies have focused on modeling, change detection and driving forces at the class or categorical level, few have focused on the subclass level, especially regarding the quality change within a class such as farmland. The concept of nondominant farmland area (NAF) is proposed in this study to assess within class variability and quantify farmland areas where poor environmental conditions, unsuitable natural factors, natural disasters or unsustainable management practices lead to poor crop growth and thus low yield. A 17-year (2000–2016) time series of the Normalized Difference Vegetation Index (NDVI) was used to develop a NAF extraction model with abnormal features in the NDVI curves and subsequently applied to Heilongjiang province in China. The NAF model was analyzed and assessed from three aspects: agricultural disasters, soil types and medium- and low-yield fields, to determine dominant factors of the NAF patterns. The results suggested that: (1) the NAF model was able to extract a variety of NAF types with an overall accuracy of ~80%. The NAF area accumulated more than 8 years in 17 years is 6.20 thousand km2 in Heilongjiang Province, accounting for 3.75% of the total cultivated land area; (2) the NAF had significant spatial clustering characteristics and temporal variability. 53.24% of the NAF accumulated more than 8 years in 17 years is mainly concentrated in the west of Heilongjiang Province. The inter-annual NAF variability was related with meteorological variations, topography and soil properties; and (3) the spatial and temporal NAF patterns seem to reflect a cumulative impact of meteorological disasters, poor farmland quality, and soil degradation on crop growth. The determinant factors of the observed NAF patterns differed across regions, and must be interpreted in the local context of topography, soil properties and meteorological environment. Spatial and temporal NAF variability could provide useful, diagnostic information for precision farmland management.
Understanding Procrastination in First-Year Undergraduates: An Application of Attribution Theory
Authors: Lee So Yeon , Hall Nathan C.
Published: July 2020

Despite findings showing first-year undergraduates persistently engage in academic procrastination, research exploring students’ perceived reasons for their procrastination and procrastination-related emotions is lacking. The present exploratory study utilized Weiner’s (2010) attribution theory to examine the relationships between procrastination as well as students’ causal explanations and emotions specific to procrastination. Findings of 429 first-year Canadian undergraduates showed students to attribute procrastination mainly to internal and stable factors, and less so to personally controllable factors. Students who attributed procrastination to reasons within themselves reported higher levels of negative emotions, with strong direct effects of procrastination on negative emotions also observed. These findings demonstrate the importance of considering students’ causal attributions as potential contributors to their emotional experiences surrounding procrastination and encourage future longitudinal research on relations between academic procrastination, attributions, and emotional outcomes.
Air Quality Uncertainty and Earnings Management
Authors: Yao Sheng , Liu Yadan
Published: July 2020

We empirically examine the influence of rising political costs from the air quality uncertainty caused by regional air quality fluctuations on firms′ earnings management. The results indicate that when air quality uncertainty increases, firms tend to increase their degree of earnings management and are more willing to carry out downward earnings management. We also find that the relationship is more obvious in the bottom-ten cities according to air quality ranking. Further evidence shows that the effect is most pronounced for less market-oriented regions, northern regions, manufacturing industries and firms with high asset-liability ratio and high media attention. In addition, we find that air quality uncertainty affects earnings management through the intermediary effect of government environmental investment. We explore the influence of the external environmental uncertainty on earnings management decisions, and the results have significant reference value for improving firms’ earnings quality level.
Integrated Sustainability Assessment of Divergent Mediterranean Farming Systems: Cyprus as a Case Study
Authors: Stylianou Andreas , Sdrali Despina , Apostolopoulos Constantinos D.
Published: July 2020

A variety of indicator-based methods have been developed for the sustainability assessment of farming systems (FSs). However, many of them lack holisticity, focus on a specific agricultural sector/product, and do not provide aggregated results to better support decision-making process. The goal of this study was, for the first time, to assess, in a holistic manner, the sustainability performance of different FSs in southeastern Cyprus. The methodological framework involved three major steps. First, the sustainability context was set, and a list of 41 environmental, social, and economic indicators was created. The indicators were then calculated using data from 324 farms. Second, six FSs were identified using multivariate analysis. Finally, the sustainability of FSs was assessed by combining numerical (construction of four composite sustainability indices) and visual (presentation of indicator scores and values with graphs and tables) integration approaches. While the indices provided the “big picture”, visual integration revealed the areas where policy interventions are needed. The analysis showed that sustainable agricultural practices are already used by some farmers in the area. The results could be used for benchmarking purposes and to aid decision-making process in Cyprus but might also be useful for other Mediterranean regions with similar agro-ecological conditions.