bluuebunny/crossref_metadata_2025 huggingface dataset:
A Study of Temperature Effect on the Xanthate’s Performance during Chalcopyrite Flotation
Authors: An Dongbo , Zhang Jinhong
Published: May 2020

A multi-scale investigation was conducted to study the surface properties of xanthate-absorbed chalcopyrite at elevated temperature to understand the temperature effect on the xanthate’s performance during chalcopyrite flotation. Firstly, a macro-scale study was initiated to investigate the temperature effect on the hydrophobicity of mineral surface by means of contact angle measurement, Hallimond tube microflotation and lab flotation tests; secondly, a micro–scale study was conducted to clarify the temperature effect on the adsorption of chemicals on mineral surface employing an atomic force microscope (AFM) and Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR). In the experiments, pure chalcopyrite samples were used for contact angle measurement, Hallimond tube microflotation, AFM and FTIR; and copper ore samples (1.51% Cu, 5.88% Fe 0.029% Mo, 5.23% S in weight percentage) were used for lab flotation tests. FTIR spectra and AFM images showed that, when potassium amyl xanthate (PAX) was used as the collector in this study, oily dixanthogen was the main hydrophobic species on the chalcopyrite surface. The morphological change of dixanthogen patches at elevated temperatures has a more significant impact than changes in the amount of adsorption species. Increasing temperature within a certain range is beneficial for the collector’s performance by increasing flotation recovery.
Preconditioning of Bioactive Glasses before Introduction to Static Cell Culture: What Is Really Necessary?
Authors: Hohenbild Frederike , Arango-Ospina Marcela , Moghaddam Arash , Boccaccini Aldo R. , Westhauser Fabian
Published: May 2020

Due to their high bioreactivity, the in-vitro analysis of bioactive glasses (BGs) can be challenging when it comes to maintaining a physiological pH. To improve BG biocompatibility, a heterogenic spectrum of preconditioning approaches, such as “passivation” of the BGs by incubation in cell culture medium, are used but have never been directly compared. In this study, the effect of passivation periods of up to 72 h on pH alkalization and viability of human bone marrow-derived mesenchymal stromal cells was evaluated to determine a time-efficient passivation protocol using granules based on the 45S5-BG composition (in wt%: 45.0 SiO2, 24.5 Na2O, 24.5 CaO, 6.0 P2O5) in different concentrations. pH alkalization was most reduced after passivation of 24 h. Cell viability continuously improved with increasing passivation time being significantly higher after passivation of at least 24 h compared to non-passivated 45S5-BG and the necessary passivation time increased with increasing BG concentrations. In this setting, a passivation period of 24 h presented as an effective approach to provide a biocompatible cell culture setting. In conclusion, before introduction of BGs in cell culture, different passivation periods should be evaluated in order to meet the respective experimental settings, e.g., by following the experimental protocols used in this study.
Synthesis and Application of Zero-Valent Iron Nanoparticles in Water Treatment, Environmental Remediation, Catalysis, and Their Biological Effects
Authors: Pasinszki Tibor , Krebsz Melinda
Published: May 2020

Present and past anthropogenic pollution of the hydrosphere and lithosphere is a growing concern around the world for sustainable development and human health. Current industrial activity, abandoned contaminated plants and mining sites, and even everyday life is a pollution source for our environment. There is therefore a crucial need to clean industrial and municipal effluents and remediate contaminated soil and groundwater. Nanosized zero-valent iron (nZVI) is an emerging material in these fields due to its high reactivity and expected low impact on the environment due to iron’s high abundance in the earth crust. Currently, there is an intensive research to test the effectiveness of nZVI in contaminant removal processes from water and soil and to modify properties of this material in order to fulfill specific application requirements. The number of laboratory tests, field applications, and investigations for the environmental impact are strongly increasing. The aim of the present review is to provide an overview of the current knowledge about the catalytic activity, reactivity and efficiency of nZVI in removing toxic organic and inorganic materials from water, wastewater, and soil and groundwater, as well as its toxic effect for microorganisms and plants.
Grey Rutile TiO2 with Long-Term Photocatalytic Activity Synthesized Via Two-Step Calcination
Authors: Liu Yan , Chen Ping , Fan Yaqi , Fan Yanfei , Shi Xifeng , Cui Guanwei , Tang Bo
Published: May 2020

Colored titanium oxides are usually unstable in the atmosphere. Herein, a gray rutile titanium dioxide is synthesized by two-step calcination successively in a high-temperature reduction atmosphere and in a lower-temperature air atmosphere. The as-synthesized gray rutile TiO2 exhibits higher photocatalytic activity than that of white rutile TiO2 and shows high chemical stability. This is attributed to interior oxygen vacancies, which can improve the separation and transmission efficiency of the photogenerated carriers. Most notably, a formed surface passivation layer will protect the interior oxygen vacancies and provide long-term photocatalytic activity.
Synthesis, Characterization and Application of Iron(II) Doped Copper Ferrites (CuII(x)FeII(1-x)FeIII2O4) as Novel Heterogeneous Photo-Fenton Catalysts
Authors: Khan Asfandyar , Valicsek Zsolt , Horváth Ottó
Published: May 2020

The heterogeneous photo-Fenton type system has huge fame in the field of wastewater treatment due to its reusability and appreciable photoactivity within a wide pH range. This research investigates the synthesis and characterization of iron(II) doped copper ferrite (CuII(x)FeII(1-x)FeIII2O4 nanoparticles (NPs) and their photocatalytic applications for the degradation of methylene blue (MB) as a model dye. The NPs were prepared via simple co-precipitation technique and calcination. The NPs were characterized by using Raman spectroscopy, X-ray diffractometry (XRD), scanning electron microscopy (SEM), and diffuse reflectance spectroscopy (DRS). SEM reveals the structural change from the spherical-like particles into needle-like fine particles as the consequence of the increasing ratio of copper(II) in the ferrites, accompanied by the decrease of the optical band-gap energies from 2.02 to 1.25 eV. The three major determinants of heterogeneous photo-Fenton system, namely NPs concentration, hydrogen peroxide concentration and pH, on the photocatalytic degradation of MB were studied. The reusability of NPs was found to be continuously increasing during 4 cycles. It was concluded that iron(II) doped copper ferrites, due to their favorable band-gap energies and peculiar structures, exhibit a strong potential for photocatalytic-degradation of dyes, for example, MB.
Structural Properties of Molecular Sierpiński Triangle Fractals
Authors: Anitas Eugen Mircea
Published: May 2020

The structure of fractals at nano and micro scales is decisive for their physical properties. Generally, statistically self-similar (random) fractals occur in natural systems, and exactly self-similar (deterministic) fractals are artificially created. However, the existing fabrication methods of deterministic fractals are seldom defect-free. Here, are investigated the effects of deviations from an ideal deterministic structure, including small random displacements and different shapes and sizes of the basic units composing the fractal, on the structural properties of a common molecular fractal—the Sierpiński triangle (ST). To this aim, analytic expressions of small-angle scattering (SAS) intensities are derived, and it is shown that each type of deviation has its own unique imprint on the scattering curve. This allows the extraction of specific structural parameters, and thus the design and fabrication of artificial structures with pre-defined properties and functions. Moreover, the influence on the SAS intensity of various configurations induced in ST, can readily be extended to other 2D or 3D structures, allowing for exploration of structure-property relationships in various well-defined fractal geometries.
Development of Nanofluids for the Inhibition of Formation Damage Caused by Fines Migration: Effect of the Interaction of Quaternary Amine (CTAB) and MgO Nanoparticles
Authors: Díez Rebeka , Medina Oscar E. , Giraldo Lady J. , Cortés Farid B. , Franco Camilo A.
Published: May 2020

Fines migration is a common problem in the oil and gas industry that causes a decrease in productivity. In this sense, the main objective of this study is to develop nanocomposites based on the interaction of quaternary amine (hexadecyltrimethylammonium bromide—CTAB) and MgO to enhance the capacity of retention of fine particles in the porous medium. MgO nanoparticles were synthesized by the sol–gel method using Mg(NO3)2·6H2O as a precursor. Nanoparticles were characterized by dynamic light scattering (DLS), the point of zero charge (pHpzc), thermogravimetric analysis, and Fourier transform infrared spectroscopy (FT-IR). Different nanoparticle sizes of 11.4, 42.8, and 86.2 nm were obtained, which were used for preparing two system nanofluids. These systems were evaluated in the inhibition of fines migration: in the system I MgO nanoparticles were dispersed in a CTAB-containing aqueous solution, and system II consists of a nanocomposite of CTAB adsorbed onto MgO nanoparticles. The fines retention tests were performed using Ottawa sand 20/40 packed beds and fine particles suspensions at concentrations of 0.2% in a mass fraction in deionized water. Individual and combined effects of nanoparticles and CTAB were evaluated in different treatment dosages. The analysis of the interactions between the CTAB and the MgO nanoparticles was carried out through batch-mode adsorption and desorption tests. The best treatment in the system I was selected according to the fines retention capacity and optimized through a simplex-centroid mixture design for mass fractions from 0.0% to 2.0% of both CTAB and MgO nanoparticles. This statistical analysis shows that the optimal concentration of these components is reached for a mass fraction of 0.73% of MgO nanoparticles and 0.74% in mass fraction of CTAB, where the retention capacity of the porous medium increases from 0.02 to 0.39 mg·L−1. Based on the experimental results, the nanofluids combining both components showed higher retention of fines than the systems treated only with CTAB or with MgO nanoparticles, with efficiencies up to 400% higher in the system I and higher up to 600% in the system II. To evaluate the best performance treatment under reservoir conditions, there were developed core flooding tests at fixed overburden pressure of 34.5 MPa, pore pressure at 6.9 MPa and system temperature at 93 °C. Obtaining critical rate increases in 142.8%, and 144.4% for water and oil flow in the presence of the nanofluid. In this sense, this work offers a new alternative for the injection of nanocomposites as a treatment for the problem of fines migration to optimize the productivity of oil and gas wells.
The Protective Effects of Acer okamotoanum and Isoquercitrin on Obesity and Amyloidosis in a Mouse Model
Authors: Kim Ji Hyun , Lee Sanghyun , Cho Eun Ju
Published: May 2020

Obesity increases risk of Alzheimer’s Disease (AD). A high fat diet (HFD) can lead to amyloidosis and amyloid beta (Aβ) accumulation, which are hallmarks of AD. In this study, protective effects of the ethyl acetate fraction of Acer okamotoanum (EAO) and isoquercitrin were evaluated on obesity and amyloidosis in the HFD- and Aβ-induced mouse model. To induce obesity and AD by HFD and Aβ, mice were provided with HFD for 10 weeks and were intracerebroventricularly injected with Aβ25–35. For four weeks, 100 and 10 mg/kg/day of EAO and isoquercitrin, respectively, were administered orally. Administration of EAO and isoquercitrin significantly decreased body weight in HFD and Aβ-injected mice. Additionally, EAO- and isoquercitrin-administered groups attenuated abnormal adipokines release via a decrease in leptin and an increase in adiponectin levels compared with the control group. Furthermore, HFD and Aβ-injected mice had damaged liver tissues, but EAO- and isoquercitrin-administered groups attenuated liver damage. Moreover, administration of EAO and isoquercitrin groups down-regulated amyloidosis-related proteins in the brain such as β-secretase, presenilin (PS)-1 and PS-2 compared with HFD and Aβ-injected mice. This study indicated that EAO and isoquercitrin attenuated HFD and Aβ-induced obesity and amyloidosis, suggesting that they could be effective in preventing and treating both obesity and AD.
Eckol from Ecklonia cava Suppresses Immunoglobulin E-mediated Mast Cell Activation and Passive Cutaneous Anaphylaxis in Mice
Authors: Han Eui , Kim Hyun-Soo , Sanjeewa K.K.A. , Herath K.H.I.N.M. , Jeon You-Jin , Jee Youngheun , Lee Jeongjun , Kim Taehee , Shim Sun-Yup , Ahn Ginnae
Published: May 2020

Eckol, a precursor compound belonging to the dibenzo-1,4-dioxin class of phlorotannins, is a phloroglucinol derivative that exerts various activities. In the present study, we investigated the antiallergic effects of eckol isolated from the marine brown algae, Ecklonia cava using immunoglobulin E (IgE)/bovine serum albumin (BSA)-stimulated mouse bone marrow-derived cultured mast cells (BMCMC) and a mouse model of anaphylaxis. Eckol inhibited IgE/BSA-induced BMCMC degranulation by reducing β-hexosaminidase release. A flow cytometric analysis revealed that eckol decreases FcεRI expression on cell surface and IgE binding to the FcεRI in BMCMC. Moreover, eckol suppressed the production of the cytokines, interleukin (IL)-4, IL-5, IL-6, and IL-13 and the chemokine, thymus activation-regulated chemokine (TARC) by downregulating, IκB-α degradation and NF-κB nuclear translocation. Furthermore, it attenuated the passive cutaneous anaphylactic reaction induced by IgE/BSA-stimulation in the ear of BALB/c mice. These results suggest that eckol is a potential therapeutic candidate for the prevention and treatment of allergic disorders.
Omega-3 PUFA Responders and Non-Responders and the Prevention of Lipid Dysmetabolism and Related Diseases
Authors: Serini Simona , Calviello Gabriella
Published: May 2020

The long-chain omega-3 polyunsaturated fatty acids (LC-omega-3 PUFAs) eicosapentaenoic acid and docosahexaenoic acid are the most popular dietary supplements recommended for the prevention/management of lipid dysmetabolisms and related diseases. However, remarkable inconsistencies exist among the outcomes of the human intervention studies in this field, which contrast with the impressive homogeneity of positive results of most of the preclinical studies. In the present review, we will firstly examine a series of factors—such as background diet composition, gut microbiota and genetic/epigenetic variants, which may lie beneath these inconsistencies. Moreover, we will discuss the recent advance in the knowledge of possible specific biomarkers (genetic-, epigenetic- and microbiota-related) that are being investigated with the goal to apply them in a personalized supplementation with omega-3 PUFAs. We will also consider the possibility of using already available parameters (Omega-3 index, Omega-6 PUFA/Omega-3 PUFA ratio) able to predict the individual responsiveness to these fatty acids and will discuss the optimal timing for their use. Finally, we will critically examine the results of those human studies that have already adopted the distinction of the subjects into omega-3 PUFA responders and non-responders and will discuss the advantage of using such an approach.
Neuroprotective Activity of Mentha Species on Hydrogen Peroxide-Induced Apoptosis in SH-SY5Y Cells
Authors: Hanafy Doaa M. , Prenzler Paul D. , Burrows Geoffrey E. , Gurusinghe Saliya , Thejer Bashar M. , Obied Hassan K. , Hill Rodney A.
Published: May 2020

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder with an unclear cause. It appears that multiple factors participate in the process of neuronal damage including oxidative stress and accumulation of the protein amyloid β (Aβ) in the brain. The search for a treatment for this disorder is essential as current medications are limited to alleviating symptoms and palliative effects. The aim of this study is to investigate the effects of mint extracts on selected mechanisms implicated in the development of AD. To enable a thorough investigation of mechanisms, including effects on β-secretase (the enzyme that leads to the formation of Aβ), on Aβ aggregation, and on oxidative stress and apoptosis pathways, a neuronal cell model, SH-SY5Y cells, was selected. Six Mentha taxa were investigated for their in vitro β-secretase (BACE) and Aβ-aggregation inhibition activities. Moreover, their neuroprotective effects on H2O2-induced oxidative stress and apoptosis in SH-SY5Y cells were evaluated through caspase activity. Real-time PCR and Western blot analysis were carried out for the two most promising extracts to determine their effects on signalling pathways in SH-SY5Y cells. All mint extracts had strong BACE inhibition activity. M. requienii extracts showed excellent inhibition of Aβ-aggregation, while other extracts showed moderate inhibition. M. diemenica and M. requienii extracts lowered caspase activity. Exposure of SH-SY5Y cells to M. diemenica extracts resulted in a decrease in the expression of pro-apoptotic protein, Bax, and an elevation in the anti-apoptotic protein, Bcl-xL, potentially mediated by down-regulation of the ASK1-JNK pathway. These results indicate that mint extracts could prevent the formation of Aβ and also could prevent their aggregation if they had already formed. M. diemenica and M. requienii extracts have potential to suppress apoptosis at the cellular level. Hence, mint extracts could provide a source of efficacious compounds for a therapeutic approach for AD.
Effects of 120 g/h of Carbohydrates Intake during a Mountain Marathon on Exercise-Induced Muscle Damage in Elite Runners
Authors: Viribay Aitor , Arribalzaga Soledad , Mielgo-Ayuso Juan , Castañeda-Babarro Arkaitz , Seco-Calvo Jesús , Urdampilleta Aritz
Published: May 2020

Background—exercise-induced muscle damage (EIMD) and internal exercise load are increased after competing in ultraendurance events such as mountain marathons. Adequate carbohydrate (CHO) intake during exercise optimizes athletic performance and could limit EIMD, reduce internal exercise load and, thus, improve recovery. Therefore, the aim of this study was to research into and compare the effects of high CHO intake (120 g/h) in terms of CHO intake recommendation (90 g/h) and regular CHO intake performed by ultraendurance athletes (60 g/h) during a mountain marathon, on exercise load and EIMD markers (creatine kinase (CK), lactate dehydrogenase (LDH), glutamic oxaloacetic transaminase (GOT), urea and creatinine). Materials and Methods—a randomized trial was carried out on 20 male elite runners who had previously undertaken nutritional and gut training, and who consumed different CHO dosages according to experimental (EXP—120 g/h), control (CON—90 g/h) and low CHO intake (LOW—60 g/h) groups during a ~4000 m cumulative slope mountain marathon. EIMD markers were analyzed before the race and 24 h afterwards. Internal exercise load was calculated based on rate of perceived exertion (RPE) during and after the marathon event. Results—internal exercise load during the mountain marathon was significantly lower (p = 0.019; η2p = 0.471) in EXP (3805 ± 281 AU) compared to LOW (4688 ± 705 AU) and CON (4692 ± 716 AU). Moreover, results revealed that the EXP group evidenced significantly lower CK (p = 0.019; η2p = 0.373), LDH (p < 0.001; η2p = 0.615) and GOT (p = 0.003; η2p = 0.500) values 24 h after the mountain marathon race compared to LOW and CON. Along these lines, EIMD and exercise load evidenced a close correlation (R = 0.742; p < 0.001). Conclusion: High CHO intake (120 g/h) during a mountain marathon could limit the EIMD observed by CK, LDH and GOT and internal exercise load compared to CHO ingestion of 60 and 90 g/h.
Prevalence, Antimicrobial Resistance Profiles, Virulence and Enterotoxins-Determinant Genes of MRSA Isolated from Subclinical Bovine Mastitis in Egypt
Authors: Algammal Abdelazeem M. , Enany Mohamed E. , El-Tarabili Reham M. , Ghobashy Madeha O. I. , Helmy Yosra A.
Published: May 2020

Subclinical mastitis caused by Staphylococcus aureus has worldwide public health significance. Here, we aimed to determine the prevalence of S. aureus, antimicrobial resistance profiles, and the virulence and enterotoxins determinant genes of MRSA strains that caused subclinical bovine mastitis. Milk samples were collected from 120 lactating animals (50 buffaloes and 70 dairy cattle) from different farms located in Ismailia Province (Egypt). The collected samples were investigated for subclinical mastitis using a California mastitis test. The total prevalence of S. aureus was 35.9% (84/234) with 36.3% (53/146) in cattle and 31% (31/88) in buffaloes. Antimicrobial susceptibility testing showed that 35.7% (30/84) of the isolated strains were resistant to cefoxitin, defined as methicillin-resistant S. aureus (MRSA), with 37.7% (20/53) in cattle and 32.2% (10/31) in buffaloes. Using PCR, 100% of the tested strains harbored coa and mecA genes, while 86.6% were positive for spa gene, with remarkable gene size polymorphism. Additionally, 10% of the tested strains contained the pvl gene. Further, using multiplex PCR, 26.6% of the tested samples had sea gene, two strains had sec gene and only one strain had sea and sec genes. The seb and sed genes were absent in the tested strains. In conclusion, mecA, coa and spa virulence genes were widely distributed in MRSA strains isolated from bovine milk, whereas the sea gene was the most predominant enterotoxin gene. Notably, this is the first report that emphasizes the prevalence of pvl gene of MRSA isolated from bovine milk in Egypt.
Exploring Kinase Inhibition Properties of 9H-pyrimido[5,4-b]- and [4,5-b]indol-4-amine Derivatives
Authors: Loidreau Yvonnick , Dubouilh-Benard Carole , Nourrisson Marie-Renée , Loaëc Nadège , Meijer Laurent , Besson Thierry , Marchand Pascal
Published: May 2020

We previously highlighted the interest in 6,5,6-fused tricyclic analogues of 4-aminoquinazolines as kinase inhibitors in the micromolar to the nanomolar range of IC50 values. For the generation of chemical libraries, the formamide-mediated cyclization of the cyanoamidine precursors was carried out under microwave irradiation in an eco-friendly approach. In order to explore more in-depth the pharmacological interest in such tricyclic skeletons, the central five member ring, i.e., thiophène or furan, was replaced by a pyrrole to afford 9H-pyrimido[5,4-b]- and [4,5-b]indol-4-amine derivatives inspired from harmine. The inhibitory potency of the final products was determined against four protein kinases (CDK5/p25, CK1δ/ε, GSK3α/β, and DYRK1A). As a result, we have identified promising compounds targeting CK1δ/ε and DYRK1A and displaying micromolar and submicromolar IC50 values.
Is the Way to Fight Cancer Paved with Gold? Metal-Based Carbene Complexes with Multiple and Fascinating Biological Features
Authors: Iacopetta Domenico , Rosano Camillo , Sirignano Marco , Mariconda Annaluisa , Ceramella Jessica , Ponassi Marco , Saturnino Carmela , Sinicropi Maria Stefania , Longo Pasquale
Published: May 2020

Herein, we report the synthesis and the multiple anti-tumor properties of new gold and silver carbene complexes. The chemical modifications, grounded on our previous studies, led us to identify a good lead complex, gold-based, whose biological features are very exciting and promising in the anti-cancer research and could be further developed. Indeed, the bis-[4,5-dichloro-(N-methyl-N’(2-hydroxy-2-phenyl)ethyl-imidazole-2-ylidene)gold(I)]+[dichloro-gold]− (AuL7) complex possesses the ability to interfere with at least three important and different intracellular targets, namely the human topoisomerases I and II and tubulin, which are able to modulate metabolic processes not directly correlated each other. We proved that the modifications of the ligands structure in AuL7, with respect to another already published complex, i.e., bis-[4,5-dichloro-(N-methyl-N’(cyclopentane-2ol)-imidazole-2-ylidine)gold(I)]+[dichloro-gold]− (AuL4), produce a different behavior toward tubulin-polymerization process, since AuL7 is a tubulin-polymerization inhibitor and AuL4 a stabilizer, with the final same result of hampering the tumor growth. Taken together, our outcomes designate AuL7 as a promising compound for the development of multi-targeted anti-cancer therapies.
Enhanced Oral Bioavailability of the Pharmacologically Active Lignin Magnolol via Zr-Based Metal Organic Framework Impregnation
Authors: Santos Joshua H. , Quimque Mark Tristan J. , Macabeo Allan Patrick G. , Corpuz Mary Jho-Anne T. , Wang Yun-Ming , Lu Tsai-Te , Lin Chia-Her , Villaflores Oliver B.
Published: May 2020

Bioavailability plays an important role in drug activity in the human body, as certain drug amounts should be present to elicit activity. However, low bioavailability of drugs leads to negligible use for human benefit. In this study, the diversely active neolignan, magnolol, was impregnated onto a Zr-based organometallic framework [Uio-66(Zr)] to increase its low bioavailability (4–5%) and to test its potential acute oral toxicity. Synthesis of Uio-66(Zr) was done through the solvothermal method while simple impregnation at different time points was used to incorporate magnolol. The loading capacity of Uio-66(Zr) at 36 h was found to be significantly higher at 72.16 ± 2.15% magnolol than in other incubation time. Based on the OECD 425 (limit test), toxicity was not observed at 2000 mg kg−1 dose of mag@Uio-66(Zr) in female Sprague Dawley rats. The area under the curve (AUC) at 0–720 min of mag@Uio-66(Zr) was significantly higher than the AUC of free magnolol. Moreover, relative bioavailability increased almost two-folds using Uio-66(Zr). Unconjugated magnolol was found in the liver, kidney, and brain of rats in all treatment groups. Collectively, Uio-66(Zr) provided a higher magnolol bioavailability when used as drug carrier. Thus, utilization of Uio-66(Zr) as drug carrier is of importance for maximal use for poorly soluble and lowly bioavailable drugs.
Influence of Polymer Composition on the Controlled Release of Docetaxel: A Comparison of Non-Degradable Polymer Films for Oesophageal Drug-Eluting Stents
Authors: Fouladian Paris , Afinjuomo Franklin , Arafat Mohammad , Bergamin Amanda , Song Yunmei , Blencowe Anton , Garg Sanjay
Published: May 2020

Following the huge clinical success of drug-eluting vascular stents, there is a significant interest in the development of drug-eluting stents for other applications, such as the treatment of gastrointestinal (GI) cancers. Central to this process is understanding how particular drugs are released from stent coatings, which to a large extent is controlled by drug-polymer interactions. Therefore, in this study we investigated the release of docetaxel (DTX) from a selection of non-degradable polymer films. DTX-polymer films were prepared at various loadings (1, 5 and 10% w/w) using three commercially available polymers including poly(dimethylsiloxane) (PSi), poly (ethylene-co-vinyl acetate) (PEVA) and Chronosil polyurethane (PU). The formulations were characterised using different techniques such as photoacoustic Fourier-transform infrared (PA-FTIR) spectrophotometry, X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The effect of DTX on the mechanical properties of the films, in-vitro release, and degradation tests were also assessed. For all polymers and DTX loadings, the drug was found to disperse homogenously without crystallisation within the polymer matrix. While no specific interactions were observed between DTX and PSi or PEVA, hydrogen-bonding appeared to be present between DTX and PU, which resulted in a concentration-dependent decrease in the Young’s moduli of the films due to disruption of inter-polymeric molecular interactions. In addition, the DTX-PU interactions were found to modulate drug release, providing near-linear release over 30 days, which was accompanied by a significant reduction in degradation products. The results indicate that DTX-loaded PU films are excellent candidates for drug-eluting stents for the treatment of oesophageal cancer.
Measuring the Development of Therapeutic-Decision-Making Skills by Practicing Pharmacists Undertaking a University-Based Postgraduate Clinical Qualification at Distance
Authors: Wright Daniel F. B. , Duffull Stephen B. , Wilby Kyle J. , Peterson Aynsley K. , Anakin Megan G.
Published: May 2020

(1) Background: The processes and skills required to make decisions about drug therapy have been termed “therapeutic decision-making” in pharmacy practice. The aim of this study was to evaluate a tool constructed to measure the development of therapeutic-decision-making skills by practicing pharmacists undertaking a university-based continuing professional development program. (2) Methods: A pre- and post-intervention crossover study design was used to investigate the qualitative and quantitative features of practicing pharmacists’ responses to two clinical vignettes designed to measure the development of therapeutic-decision-making skills. The vignettes were assigned a score using a five-point scale and compared pre- and post-intervention. (3) Results: There was a median increase in score of 2 units on the five-point scale in the post-intervention scores compared to pre-intervention (p < 0.0001). (4) Conclusions: The results were interpreted to suggest that the participants’ responses to the vignettes are a reasonable measure of student learning. Therefore, we infer that the teaching and learning intervention successfully enabled the development of therapeutic-decision-making skills by practicing pharmacists.
Influence of Genipin Crosslinking on the Properties of Chitosan-Based Films
Authors: Kildeeva Nataliya , Chalykh Anatoliy , Belokon Mariya , Petrova Tatyana , Matveev Vladimir , Svidchenko Evgeniya , Surin Nikolay , Sazhnev Nikita
Published: May 2020

Chitosan is a promising environment friendly active polymer packaging material due to its biodegradability, exceptional film forming capacity, great mechanical strength, appropriate barrier property along with intrinsic antioxidant and antimicrobial features. Bifunctional reagent was used for producing water insoluble chitosan films. Biopolymeric films crosslinked by Genipin (Gp), which is a reagent of natural origin, should have high potential in food packaging. The influence of the ratio of functional groups in the chitosan-Gp system on film absorption in the visible and ultraviolet regions of the spectrum, sorption, physical, and mechanical properties of the films has been studied. The degree of chitosan crosslinking in the films obtained from solutions containing Gp was estimated using the experimental data on film swelling and water vapor sorption isotherms. It is demonstrated that crosslinking with genipin improves swelling, water resistance, and mechanical properties of the films.
Laboratory Evaluation on the Performance Degradation of Styrene-Butadiene-Styrene-Modified Asphalt Mixture Reinforced with Basalt Fiber under Freeze–Thaw Cycles
Authors: Cheng Yongchun , Li He , Wang Wensheng , Li Liding , Wang Haitao
Published: May 2020

This paper aims at the freeze–thaw (F-T) cycles resistance of styrene-butadiene-styrene (SBS) modified asphalt mixture reinforced with basalt fiber in order to explore the performance evaluation and prediction of asphalt mixtures at seasonal frozen regions. Asphalt was firstly modified by the common SBS and then SBS-modified stone mastic asphalt (SMA) specimens with basalt fiber were prepared by using Superpave gyratory compaction (SGC) method. Next, asphalt mixture specimens processed by 0–21 F-T cycles were adopted for the high-temperature compression test, low-temperature splitting test and indirect tensile stiffness modulus test. Meanwhile, a three-dimensional model of F-T damage evolution of the mixtures was also established based on the reliability and damage theory. The test results showed that the loss rates of mechanical strength increased rapidly, and then gradually flattened; however, these indications changed significantly after 15–18 F-T cycles. In addition, the exponential function could reflect the variation trend of the mechanical performances with F-T cycles to a certain degree. The damage evolution and prediction model based on the reliability and damage theory can be established to analyze the internal degradation law better.
Electrospun Silk-Boron Nitride Nanofibers with Tunable Structure and Properties
Authors: Xue Ye , Hu Xiao
Published: May 2020

In this study, hexagonal boron nitride (h-BN) nanosheets and Bombyx mori silk fibroin (SF) proteins were combined and electrospun into BNSF nanofibers with different ratios. It was found that the surface morphology and crosslinking density of the nanofibers can be tuned through the mixing ratios. Fourier transform infrared spectroscopy study showed that pure SF electrospun fibers were dominated by random coils and they gradually became α-helical structures with increasing h-BN nanosheet content, which indicates that the structure of the nanofiber material is tunable. Thermal stability of electrospun BNSF nanofibers were largely improved by the good thermal stability of BN, and the strong interactions between BN and SF molecules were revealed by temperature modulated differential scanning calorimetry (TMDSC). With the addition of BN, the boundary water content also decreased, which may be due to the high hydrophobicity of BN. These results indicate that silk-based BN composite nanofibers can be potentially used in biomedical fields or green environmental research.
Thermally Optimum Spacing between Inner Plates in Natural Convection Flows in Cavities by Numerical Investigation
Authors: Zamora Blas
Published: May 2020

Buoyancy-driven airflow that included two isothermal inner plates established in a vented cavity is investigated numerically. The thermally optimum wall-to-wall spacing of the immersed channel, as well as its dependence with respect to the relevant governing parameters, are determined. Results are presented as a function of the aspect ratio b/H for a wide range of Rayleigh numbers RaH. A logarithmic correlation for the optimum (b/H)opt as a function of RaH is presented. In addition, since the outlined configuration might be subject to intense heating conditions, the influence of considering variable thermophysical properties is also included in the analysis. In fact, an appreciable influence of the variation of properties on (b/H)opt is also detected for a representative value of RaH = 109. Obtained results can be directly applied to the optimization of electronic equipment cooling, or even to thermal passive devices in buildings.
Cyclic Sequential Removal of Alizarin Red S Dye and Cr(VI) Ions Using Wool as a Low-Cost Adsorbent
Authors: Khamis Mustafa I. , Ibrahim Taleb H. , Jumean Fawwaz H. , Sara Ziad A. , Atallah Baraa A.
Published: May 2020

Alizarin red S (ARS) removal from wastewater using sheep wool as adsorbent was investigated. The influence of contact time, pH, adsorbent dosage, initial ARS concentration and temperature was studied. Optimum values were: pH = 2.0, contact time = 90 min, adsorbent dosage = 8.0 g/L. Removal of ARS under these conditions was 93.2%. Adsorption data at 25.0 °C and 90 min contact time were fitted to the Freundlich and Langmuir isotherms. R2 values were 0.9943 and 0.9662, respectively. Raising the temperature to 50.0 °C had no effect on ARS removal. Free wool and wool loaded with ARS were characterized by Fourier Transform Infrared Spectroscopy (FTIR). ARS loaded wool was used as adsorbent for removal of Cr(VI) from industrial wastewater. ARS adsorbed on wool underwent oxidation, accompanied by a simultaneous reduction of Cr(VI) to Cr(III). The results hold promise for wool as adsorbent of organic pollutants from wastewater, in addition to substantial self-regeneration through reduction of toxic Cr(VI) to Cr(III). Sequential batch reactor studies involving three cycles showed no significant decline in removal efficiencies of both chromium and ARS.
Special Issue on "Thin Film Processes"
Authors: Jung Hyun Wook
Published: May 2020

Thin film processes are significantly incorporated in manufacturing display panels, secondary batteries, fuel/solar cells, catalytic films, membranes, adhesives, and other commodity films [...]
Adventists in Montenegro—From the Atheistic Psychosis of Socialism to the Post-socialist Individuation of Adventism
Authors: Bakrač Vladimir , Vuković-Ćalasan Danijela , Živković Predrag , Šarović Rade
Published: May 2020

The process of converting individuals to a particular religious community is one of the issues addressed by the Sociology of Religion. In the post-socialist Montenegrin society, there have been research works related to dominant religious communities, the Orthodox, the Roman Catholic, and the Islamic, while science has shown no interest in small religious groups. The Adventist movement in Montenegro, although present for a long period of time, has failed to mobilise individuals for conversion to a greater extent. Therefore, this research aims to find out when, under what conditions and in what way the individuals in Montenegro, as a post-socialist state, chose Adventism as religious affiliation, what affected this process the most, and were there any specificities in that regard. This paper is a result of a survey conducted via an in-depth interview with 17 believers of the Adventist Church. The obtained results indicate several valuable data: most respondents accepted the Adventist movement in Montenegro in the early 1990s; they got first-hand knowledge of this religion from their friends or wider family members and relatives, a consistent interpretation of the Holy Bible is the main reason for conversion. A significant factor in the process of conversion to Adventism is early religious socialisation within a family.
Spiritual Needs Questionnaire (SpNQ): Validity Evidence among HIV+ Patients in Northeast Brazil
Authors: Oliveira da Silva Cassiano Augusto , Rodrigues Cavalcanti Ana Paula , da Silva Lima Kaline , Macêdo Cavalcanti Carlos André , de Oliveira Valente Tânia Cristina , Büssing Arndt
Published: May 2020

The Spiritual Needs Questionnaire (SpNQ) measures psychosocial, existential, and spiritual needs in clinical contexts. The objective was to confirm its factor structure in Brazil, comparing the results of its validation for Portuguese in Rio de Janeiro, under similar sampling conditions, in João Pessoa (Paraíba-Brazil), among 157 HIV(Human Immunodeficiency Virus)+ patients, most of them men (49%) (women = 35%; other = 16%), aged between 30 and 49 years (53.5%). From exploratory factor analysis and internal consistency analysis a structure of five factors (or components) was obtained: Religious Needs (α = 0.73), Inner Peace and Family Support Needs, gathered (α = 0.64), Existential Needs (α = 0.49) and two new factors instead of “Giving/Generativity Needs”, being Social Recognition Needs (α = 0.54), referring explicitly to religious practices, with items formerly found in the Religious Needs factor, and Time Domain: Reflection and Clarification Needs (α = 0.57), which group only two items (item 4, “reflection on the past” (formerly in the Inner Peace component) and item 5, “resolution of outstanding problems”). The institutional religiosity perceived in the composition of the Social Recognition Needs component shows that these patients differentiate “religiosity” from “spirituality”. The Religious Needs component was formed with items from the “spirituality” construct definition. The most important component was Inner Peace and Family Support Needs, a relevant coping strategy in this disease. The results met proper validity criteria, and SpNQ proved to be sensitive and appropriate to situations of cultural and clinical diversity between samplings.
When Piety Is Not Enough: Religio-Political Organizations in Pursuit of Peace and Reconciliation in Zimbabwe
Authors: Tarusarira Joram
Published: May 2020

In post-independence Zimbabwe, religion has been associated with piety and acquiescence rather than radical confrontation. This has made it look preposterous for religious leaders to adopt seemingly radical and confrontational stances in pursuit of peace and reconciliation. Since the early 2000s, a new breed of religious leaders that deploy radical and confrontational strategies to pursue peace has emerged in Zimbabwe. Rather than restricting pathways to peace and reconciliation to nonconfrontational approaches such as empathy, pacifism, prayer, meditation, love, repentance, compassion, apology and forgiveness, these religious leaders have extended them to demonstrations, petitions and critically speaking out. Because these religious leaders do not restrict themselves to the methods and strategies of engagement and dialogue advocated by mainstream church leaders, mainstream church leaders and politicians condemn them as nonconformists that transcend their religious mandate. These religious leaders have redefined and reframed the meaning and method of pursuing peace and reconciliation in Zimbabwe and brought a new consciousness on the role of religious leaders in times of political violence and hostility. Through qualitative interviews with religious leaders from a network called Churches in Manicaland in Zimbabwe, which emerged at the height of political violence in the early 2000s, and locating the discussion within the discourse of peace and reconciliation, this article argues that the pursuit of peace and reconciliation by religious actors is not a predefined and linear, but rather a paradoxical and hermeneutical exercise which might involve seemingly contradictory approaches such as “hard” and “soft” strategies. Resultantly, religio-political nonconformism should not be perceived as a stubborn departure from creeds and conventions, but rather as a phenomenon that espouses potential to positively change socio-economic and political dynamics that advance peace and reconciliation.
Rapid Determination of Soil Class Based on Visible-Near Infrared, Mid-Infrared Spectroscopy and Data Fusion
Authors: Xu Hanyi , Xu Dongyun , Chen Songchao , Ma Wanzhu , Shi Zhou
Published: May 2020

Wise soil management requires detailed soil information, but conventional soil class mapping in a rather coarse spatial resolution cannot meet the demand for precision agriculture. With the advantages of non-destructiveness, rapid cost-efficiency, and labor savings, the spectroscopic technique has proved its high potential for success in soil classification. Previous studies mainly focused on predicting soil classes using a single sensor. In this study, we attempted to compare the predictive ability of visible near infrared (vis-NIR) spectra, mid-infrared (MIR) spectra, and their fused spectra for soil classification. A total of 146 soil profiles were collected from Zhejiang, China, and the soil properties and spectra were measured by their genetic horizons. Along with easy-to-measure auxiliary soil information (soil organic matter, soil texture, color and pH), four spectral data, including vis-NIR, MIR, their simple combination (vis-NIR-MIR), and outer product analysis (OPA) fused spectra, were used for soil classification using a multiple objectives mixed support vector machine model. The independent validation results showed that the classification model using MIR (accuracy of 64.5%) was slightly better than that using vis-NIR (accuracy of 64.2%). The predictive model built on vis-NIR-MIR did not improve the classification accuracy, having the lowest accuracy of 61.1%, which likely resulted from an over-fitting problem. The model based on OPA fused spectra performed best with an accuracy of 68.4%. Our results prove the potential of fusing vis-NIR and MIR using OPA for improving prediction ability for soil classification.
Estimating Stem Volume in Eucalyptus Plantations Using Airborne LiDAR: A Comparison of Area- and Individual Tree-Based Approaches
Authors: Leite Rodrigo Vieira , Amaral Cibele Hummel do , Pires Raul de Paula , Silva Carlos Alberto , Soares Carlos Pedro Boechat , Macedo Renata Paulo , Silva Antonilmar Araújo Lopes da , Broadbent Eben North , Mohan Midhun , Leite Hélio Garcia
Published: May 2020

Forest plantations are globally important for the economy and are significant for carbon sequestration. Properly managing plantations requires accurate information about stand timber stocks. In this study, we used the area (ABA) and individual tree (ITD) based approaches for estimating stem volume in fast-growing Eucalyptus spp forest plantations. Herein, we propose a new method to improve individual tree detection (ITD) in dense canopy homogeneous forests and assess the effects of stand age, slope and scan angle on ITD accuracy. Field and Light Detection and Ranging (LiDAR) data were collected in Eucalyptus urophylla x Eucalyptus grandis even-aged forest stands located in the mountainous region of the Rio Doce Valley, southeastern Brazil. We tested five methods to estimate volume from LiDAR-derived metrics using ABA: Artificial Neural Network (ANN), Random Forest (RF), Support Vector Machine (SVM), and linear and Gompertz models. LiDAR-derived canopy metrics were selected using the Recursive Feature Elimination algorithm and Spearman’s correlation, for nonparametric and parametric methods, respectively. For the ITD, we tested three ITD methods: two local maxima filters and the watershed method. All methods were tested adding our proposed procedure of Tree Buffer Exclusion (TBE), resulting in 35 possibilities for treetop detection. Stem volume for this approach was estimated using the Schumacher and Hall model. Estimated volumes in both ABA and ITD approaches were compared to the field observed values using the F-test. Overall, the ABA with ANN was found to be better for stand volume estimation ( r y y ^ = 0.95 and RMSE = 14.4%). Although the ITD results showed similar precision ( r y y ^ = 0.94 and RMSE = 16.4%) to the ABA, the results underestimated stem volume in younger stands and in gently sloping terrain (<25%). Stem volume maps also differed between the approaches; ITD represented the stand variability better. In addition, we discuss the importance of LiDAR metrics as input variables for stem volume estimation methods and the possible issues related to the ABA and ITD performance.