bluuebunny/crossref_metadata_2025 huggingface dataset:
Wetting Transitions of Liquid Gallium Film on Nanopillar-Decorated Graphene Surfaces
Authors: Wang Junjun , Li Tao , Li Yifan , Duan Yunrui , Jiang Yanyan , Arandiyan Hamidreza , Li Hui
Published: September 2018

Molecular dynamics (MD) simulation has been employed to study the wetting transitions of liquid gallium droplet on the graphene surfaces, which are decorated with three types of carbon nanopillars, and to explore the effect of the surface roughness and morphology on the wettability of liquid Ga. The simulation results showed that, at the beginning, the Ga film looks like an upside-down dish on the rough surface, different from that on the smooth graphene surface, and its size is crucial to the final state of liquid. Ga droplets exhibit a Cassie–Baxter (CB) state, a Wenzel state, a Mixed Wetting state, and a dewetting state on the patterned surfaces by changing distribution and the morphology of nanopillars. Top morphology of nanopillars has a direct impact on the wetting transition of liquid Ga. There are three transition states for the two types of carbon nanotube (CNT) substrates and two for the carbon nanocone (CNC) one. Furthermore, we have found that the substrates show high or low adhesion to the Ga droplet with the variation of their roughness and top morphology. With the roughness decreasing, the adhesion energy of the substrate decreases. With the same roughness, the CNC/graphene surface has the lowest adhesion energy, followed by CNT/graphene and capped CNT/graphene surfaces. Our findings provide not only valid support to previous works but also reveal new theories on the wetting model of the metal droplet on the rough substrates.
Practical Enantioselective Reduction of Ketones Using Oxazaborolidine Catalysts Generated In Situ from Chiral Lactam Alcohols
Authors: Kawanami Yasuhiro , Yanagita Ryo C.
Published: September 2018

Oxazaborolidine catalyst (CBS catalyst) has been extensively used for catalytic borane reduction with a predictable absolute stereochemistry and high enantioselectivity. However, the use of isolated CBS catalyst sometimes has the drawback of low reproducibility due to the aging of the CBS catalyst during storage. Therefore, we investigated a more reliable and practical method for the reduction of a variety of ketones including challenging substrates, primary aliphatic ketones, α,β-enones, and trifluoromethyl ketones. This review surveys the developments in borane reduction using oxazaborolidine catalysts generated in situ from chiral lactam alcohols and borane.
Chemical Reporters and Their Bioorthogonal Reactions for Labeling Protein O-GlcNAcylation
Authors: Kim Eun Ju
Published: September 2018

Protein O-GlcNAcylation is a non-canonical glycosylation of nuclear, mitochondrial, and cytoplasmic proteins with the attachment of a single O-linked β-N-acetyl-glucosamine (O-GlcNAc) moiety. Advances in labeling and identifying O-GlcNAcylated proteins have helped improve the understanding of O-GlcNAcylation at levels that range from basic molecular biology to cell signaling and gene regulation to physiology and disease. This review describes these advances in chemistry involving chemical reporters and their bioorthogonal reactions utilized for detection and construction of O-GlcNAc proteomes in a molecular mechanistic view. This detailed view will help better understand the principles of the chemistries utilized for biology discovery and promote continued efforts in developing new molecular tools and new strategies to further explore protein O-GlcNAcylation.
Ruthenium-Based Catalytic Systems Incorporating a Labile Cyclooctadiene Ligand with N-Heterocyclic Carbene Precursors for the Atom-Economic Alcohol Amidation Using Amines
Authors: Chen Cheng , Miao Yang , De Winter Kimmy , Wang Hua-Jing , Demeyere Patrick , Yuan Ye , Verpoort Francis
Published: September 2018

Transition-metal-catalyzed amide-bond formation from alcohols and amines is an atom-economic and eco-friendly route. Herein, we identified a highly active in situ N-heterocyclic carbene (NHC)/ruthenium (Ru) catalytic system for this amide synthesis. Various substrates, including sterically hindered ones, could be directly transformed into the corresponding amides with the catalyst loading as low as 0.25 mol.%. In this system, we replaced the p-cymene ligand of the Ru source with a relatively labile cyclooctadiene (cod) ligand so as to more efficiently obtain the corresponding poly-carbene Ru species. Expectedly, the weaker cod ligand could be more easily substituted with multiple mono-NHC ligands. Further high-resolution mass spectrometry (HRMS) analyses revealed that two tetra-carbene complexes were probably generated from the in situ catalytic system.
Synthesis and Characterization of Poly(Vinyl Alcohol)-Chitosan-Hydroxyapatite Scaffolds: A Promising Alternative for Bone Tissue Regeneration
Authors: Pineda-Castillo Sergio , Bernal-Ballén Andrés , Bernal-López Cristian , Segura-Puello Hugo , Nieto-Mosquera Diana , Villamil-Ballesteros Andrea , Muñoz-Forero Diana , Munster Lukas
Published: September 2018

Scaffolds can be considered as one of the most promising treatments for bone tissue regeneration. Herein, blends of chitosan, poly(vinyl alcohol), and hydroxyapatite in different ratios were used to synthesize scaffolds via freeze-drying. Mechanical tests, FTIR, swelling and solubility degree, DSC, morphology, and cell viability were used as characterization techniques. Statistical significance of the experiments was determined using a two-way analysis of variance (ANOVA) with p < 0.05. Crosslinked and plasticized scaffolds absorbed five times more water than non-crosslinked and plasticized ones, which is an indicator of better hydrophilic features, as well as adequate resistance to water without detriment of the swelling potential. Indeed, the tested mechanical properties were notably higher for samples which were undergone to crosslinking and plasticized process. The presence of chitosan is determinant in pore formation and distribution which is an imperative for cell communication. Uniform pore size with diameters ranging from 142 to 519 µm were obtained, a range that has been described as optimal for bone tissue regeneration. Moreover, cytotoxicity was considered as negligible in the tested conditions, and viability indicates that the material might have potential as a bone regeneration system.
Design, Synthesis and Docking Studies of Novel Macrocyclic Pentapeptides as Anticancer Multi-Targeted Kinase Inhibitors
Authors: Amr Abd El-Galil E. , Abo-Ghalia Mohamed H. , Moustafa Gaber O. , Al-Omar Mohamed A. , Nossier Eman S. , Elsayed Elsayed A.
Published: September 2018

A series of macrocyclic pyrido-pentapeptide candidates 2–6 were synthesized by using N,N-bis-[1-carboxy-2-(benzyl)]-2,6-(diaminocarbonyl)pyridine 1a,b as starting material. Structures of the newly synthesized compounds were established by IR, 1H and 13C-NMR, and MS spectral data and elemental analysis. The in-vitro cytotoxicity activity was investigated for all compounds against MCF-7 and HepG-2 cell lines and the majority of the compounds showed potent anticancer activity against the tested cell lines in comparison with the reference drugs. Out of the macrocyclic pyrido-pentapeptide based compounds, 5c showed encouraging inhibitory activity on MCF-7 and HepG-2 cell lines with IC50 values 9.41 ± 1.25 and 7.53 ± 1.33 μM, respectively. Interestingly, 5c also demonstrated multitarget profile and excellent inhibitory activity towards VEGFR-2, CDK-2 and PDGFRβ kinases. Furthermore, molecular modeling studies of the compound 5c revealed its possible binding modes into the active sites of those kinases.
Influence of Eugenia uniflora Extract on Adhesion to Human Buccal Epithelial Cells, Biofilm Formation, and Cell Surface Hydrophobicity of Candida spp. from the Oral Cavity of Kidney Transplant Recipients
Authors: Souza Luanda , Silva-Rocha Walicyranison , Ferreira Magda , Soares Luiz , Svidzinski Terezinha , Milan Eveline , Pires Regina , Fusco Almeida Ana , Mendes-Giannini Maria , Maranhão Chaves Guilherme
Published: September 2018

This study evaluated the influence of the extract of Eugenia uniflora in adhesion to human buccal epithelial cells (HBEC) biofilm formation and cell surface hydrophobicity (CSH) of Candida spp. isolated from the oral cavity of kidney transplant patients. To evaluate virulence attributes in vitro, nine yeasts were grown in the presence and absence of 1000 μg/mL of the extract. Adhesion was quantified using the number of Candida cells adhered to 150 HBEC determined by optical microscope. Biofilm formation was evaluated using two methodologies: XTT (2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide) and crystal violet assay, and further analyzed by electronic scan microscopy. CSH was quantified with the microbial adhesion to hydrocarbons test. We could detect that the extract of E. uniflora was able to reduce adhesion to HBEC and CSH for both Candida albicans and non-Candida albicans Candida species. We also observed a statistically significant reduced ability to form biofilms in biofilm-producing strains using both methods of quantification. However, two highly biofilm-producing strains of Candida tropicalis had a very large reduction in biofilm formation. This study reinforces the idea that besides growth inhibition, E. uniflora may interfere with the expression of some virulence factors of Candida spp. and may be possibly applied in the future as a novel antifungal agent.
Hepatoprotective Effect of Ugonin M, A Helminthostachys zeylanica Constituent, on Acetaminophen-Induced Acute Liver Injury in Mice
Authors: Wu Kun-Chang , Ho Yu-Ling , Kuo Yueh-Hsiung , Huang Shyh-Shyun , Huang Guan-Jhong , Chang Yuan-Shiun
Published: September 2018

The present study aimed to discover the possible effectiveness of Ugonin M, a unique flavonoid isolated from Helminthostachys zeylanica—a traditional Chinese medicine used as anti-inflammatory medicine—and to elucidate the potential mechanisms of Ugonin M in the acute liver injury induced by acetaminophen (APAP). In this study, Ugonin M significantly ameliorated APAP-induced histopathological changes and the typical liver function biomarkers (i.e., alanine aminotransferase (ALT), aspartate aminotransferase (AST), and total bilirubin (T-Bil)). It also affected APAP-induced abnormal lipid metabolism including total cholesterol (TC) and triglyceride (TG) in the serum. In inflammatory pharmacological action, Ugonin M suppressed the pro-inflammatory mediators such as nitric oxide (NO) and the lipid peroxidation indicator malondialdehyde (MDA). In addition, Ugonin M reinforced hemeoxygenase-1 (HO-1) protein expression and the production of antioxidant enzymes viz superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT). Furthermore, inflammation-associated cytokines including tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and IL-1β as well as proteins such as inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were decreased by the pretreatment of Ugonin M. Moreover, this study found that pretreatment of Ugonin M apparently decreased nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs) activation via inhibition of the degradation of NF-κB, inhibitory κB-α (IκB-α), extracellular regulated kinase (ERK), c-Jun-N-terminal (JNK), and p38 active phosphorylation. In conclusion, Ugonin M significantly showed a protective effect against APAP-induced liver injury by reducing oxidative stress and inflammation. Thus, Ugonin M could be one of the effective components of H. zeylanica that plays a major role in the treatment of inflammatory disorders.
Avocado Seed: A Comparative Study of Antioxidant Content and Capacity in Protecting Oil Models from Oxidation
Authors: Segovia Francisco J. , Hidalgo Gádor Indra , Villasante Juliana , Ramis Xavier , Almajano María Pilar
Published: September 2018

Increasingly, consumers want products containing little or no synthetic compounds. Avocado seeds, which are a residue of the food industry, could be used to obtain extracts with high antioxidant power. In the present study, the most popular radical scavenging methods are presented, establishing a comparison between them, besides working with two different extractions: pure methanol and ethanol–water (50:50 v/v). The radical scavenging assay methods ORAC and ABTS were performed, as well as a novel method: the reaction to methoxy radical, as determined by electron paramagnetic resonance (EPR). Peroxide value and thiobarbituric acid reactive compounds (TBARs) were used to monitor the oxidation of avocado seed oil, as well as the power of the avocado seed extract (ASE) to delay oil oxidation by oxidation induction time (OIT) and measured by differential scanning calorimetry (DSC). Radical scavenging methods have values between 1310–263 µmol TE/g of mass dissolved for ORAC and ABTS, respectively. The individual contribution of each of the compounds present in the extract was analyzed. The sum of all of them contributed up to 84% of the total radical scavenging activity. The concentration of 0.75% ASE causes a delay in the oxidation that is close to 80%, as measured by OIT. This implies that avocado seed residue may have a use as a natural antioxidant source, providing added value to organic waste.
Disubstituted 4-Chloro-3-nitrophenylthiourea Derivatives: Antimicrobial and Cytotoxic Studies
Authors: Bielenica Anna , Sanna Giuseppina , Madeddu Silvia , Giliberti Gabriele , Stefańska Joanna , Kozioł Anna E. , Savchenko Oleksandra , Strzyga-Łach Paulina , Chrzanowska Alicja , Kubiak-Tomaszewska Grażyna , Struga Marta
Published: September 2018

4-Chloro-3-nitrophenylthioureas 1–30 were synthesized and tested for their antimicrobial and cytotoxic activities. Compounds exhibited high to moderate antistaphylococcal activity against both standard and clinical strains (MIC values 2–64 μg/mL). Among them derivatives with electron-donating alkyl substituents at the phenyl ring were the most promising. Moreover, compounds 1–6 and 8–19 were cytotoxic against MT-4 cells and various other cell lines derived from human hematological tumors (CC50 ≤ 10 μM). The influence of derivatives 11, 13 and 25 on viability, mortality and the growth rate of immortalized human keratinocytes (HaCaT) was observed.
Isolation, Characterization and Antitumor Effect on DU145 Cells of a Main Polysaccharide in Pollen of Chinese Wolfberry
Authors: Chen Fei , Ran Linwu , Mi Jia , Yan Yamei , Lu Lu , Jin Bo , Li Xiaoying , Cao Youlong
Published: September 2018

Modern studies have shown that pollen has a certain role in the treatment of prostate-related diseases. In the present study, pollen polysaccharides from Chinese wolfberry (WPPs) were extracted by hot-water extraction and ethanol precipitation, further purified by chromatography on a DEAE-cellulose column and Sephadex G-100 column. Homogeneous polysaccharide CF1 of WPPS was obtained, the molecular weight of which was estimated to be 1540.10 ± 48.78 kDa by HPGPC-ELSD. HPLC with PMP derivatization analysis indicated that the monosaccharide compositions of CF1 were mannose, glucuronic acid, galacturonic acid, xylose, galactose, arabinose, and trehalose, in a molar ratio of 0.68:0.59:0.27:0.24:0.22:0.67:0.08. The antitumor effects of CF1 upon MTT, Tunel assay and flow cytometry assay were investigated in vitro. The results showed that CF1 exhibited a dose-dependent antiproliferative effect, with an IC50 value of 374.11 μg/mL against DU145 prostate cancer cells. Tunel assay and flow cytometry assay showed that the antitumor activity of CF1 was related to apoptosis in vitro. The present study suggested that the CF1 of WPPs might be a potential source of antitumor functional food or agent.
Promoting a Healthy Diet in Young Adults: The Role of Nutrition Labelling
Authors: Buyuktuncer Zehra , Ayaz Aylin , Dedebayraktar Damla , Inan-Eroglu Elif , Ellahi Basma , Besler Halit Tanju
Published: September 2018

The use of the nutrition facts label has been associated with healthy eating behaviors for adults. However, the relationship between nutrition facts label use and overall diet quality is not well known in young adults, a vulnerable group that acquire lifelong eating behaviors during this period of life. This study aimed to assess if the use of information on the nutrition facts label is associated with a higher diet quality in young adults. In this cross-sectional study, 958 university students aged 18–34 years were recruited. Nutrition facts label use was recorded. Dietary intake was assessed using 24-h dietary recall. Healthy Eating Index-2005 (HEI-2005) scores were calculated. HEI-2005 score was significantly associated with using nutrition facts label (p < 0.001). The mean total HEI-2005 score was 60.7 ± 10.11, 62.4 ± 11.43 and 67.1 ± 12.23 respectively for never, sometimes and everytime users of nutrition facts label (p < 0.001). Sub-group scores of HEI-2005 for total fruits, whole fruits, total vegetables, whole grains, milk, oils, saturated fat, and calories from solid fat, alcohol and added sugar (SoFAAS) were significantly higher in regular nutrition facts label users (p < 0.05, for each). This study showed that young adults who regularly use the nutrition facts label have a higher diet quality.
NADH Dehydrogenase Subunit-2 237 Leu/Met Polymorphism Influences the Association of Coffee Consumption with Serum Chloride Levels in Male Japanese Health Checkup Examinees: An Exploratory Cross-Sectional Analysis
Authors: Kokaze Akatsuki , Ishikawa Mamoru , Matsunaga Naomi , Karita Kanae , Yoshida Masao , Ochiai Hirotaka , Shirasawa Takako , Yoshimoto Takahiko , Minoura Akira , Oikawa Kosuke , Satoh Masao , Hoshino Hiromi , Takashima Yutaka
Published: September 2018

Background: Nicotinamide adenine dinucleotide (NADH) dehydrogenase subunit-2 237 leucine/methionine (ND2-237 Leu/Met) polymorphism has been shown to modify the association of coffee consumption with the risk of hypertension, dyslipidemia, and abnormal glucose tolerance, and low serum chloride levels have been shown to be associated with all-cause and cardiovascular disease mortality. Therefore, the purpose of the present study was to investigate whether ND2-237 Leu/Met polymorphism influences the association of coffee consumption with serum chloride levels in male Japanese health checkup examinees. Methods: From among individuals visiting the hospital for a regular medical checkup, 402 men (mean age ± standard deviation, 53.9 ± 7.8 years) were selected for inclusion in the study. After ND2-237 Leu/Met genotyping, we conducted an exploratory cross-sectional study to examine the combined association of ND2-237 Leu/Met polymorphism and coffee consumption with serum electrolyte levels. Results: After adjusting for age, body mass index, habitual smoking, alcohol consumption, green tea consumption, and antihypertensive medication, coffee consumption significantly increased serum chloride levels (p for trend = 0.001) in men with the ND2-237Leu genotype. After these adjustments, the odds ratios (ORs) for low levels of serum chloride, defined as <100 mEq/L, were found to be dependent on coffee consumption (p for trend = 0.001). In addition, the OR for low levels of serum chloride was significantly lower in men with the ND2-237Leu genotype who consumed ≥4 compared with <1 cup of coffee per day (OR = 0.096, 95% confidence interval = 0.010–0.934; p = 0.044). However, neither serum chloride levels nor risk of low levels of serum chloride appeared to be dependent on coffee consumption. Conclusions: The results suggest that ND2-237 Leu/Met polymorphism modifies the association of coffee consumption with serum chloride levels in middle-aged Japanese men.
Orosensory Detection of Dietary Fatty Acids Is Altered in CB1R−/− Mice
Authors: Brissard Léa , Leemput Julia , Hichami Aziz , Passilly-Degrace Patricia , Maquart Guillaume , Demizieux Laurent , Degrace Pascal , Khan Naim Akhtar
Published: September 2018

Obesity is one of the major public health issues, and its prevalence is steadily increasing all the world over. The endocannabinoid system (ECS) has been shown to be involved in the intake of palatable food via activation of cannabinoid 1 receptor (CB1R). However, the involvement of lingual CB1R in the orosensory perception of dietary fatty acids has never been investigated. In the present study, behavioral tests on CB1R−/− and wild type (WT) mice showed that the invalidation of Cb1r gene was associated with low preference for solutions containing rapeseed oil or a long-chain fatty acid (LCFA), such as linoleic acid (LA). Administration of rimonabant, a CB1R inverse agonist, in mice also brought about a low preference for dietary fat. No difference in CD36 and GPR120 protein expressions were observed in taste bud cells (TBC) from WT and CB1R−/− mice. However, LCFA induced a higher increase in [Ca2+]i in TBC from WT mice than that in TBC from CB1R−/− mice. TBC from CB1R−/− mice also exhibited decreased Proglucagon and Glp-1r mRNA and a low GLP-1 basal level. We report that CB1R is involved in fat taste perception via calcium signaling and GLP-1 secretion.
The Influence of Polymers on the Supersaturation Potential of Poor and Good Glass Formers
Authors: Blaabjerg Lasse I. , Grohganz Holger , Lindenberg Eleanor , Löbmann Korbinian , Müllertz Anette , Rades Thomas
Published: September 2018

The increasing number of poorly water-soluble drug candidates in pharmaceutical development is a major challenge. Enabling techniques such as amorphization of the crystalline drug can result in supersaturation with respect to the thermodynamically most stable form of the drug, thereby possibly increasing its bioavailability after oral administration. The ease with which such crystalline drugs can be amorphized is known as their glass forming ability (GFA) and is commonly described by the critical cooling rate. In this study, the supersaturation potential, i.e., the maximum apparent degree of supersaturation, of poor and good glass formers is investigated in the absence or presence of either hypromellose acetate succinate L-grade (HPMCAS-L) or vinylpyrrolidine-vinyl acetate copolymer (PVPVA64) in fasted state simulated intestinal fluid (FaSSIF). The GFA of cinnarizine, itraconazole, ketoconazole, naproxen, phenytoin, and probenecid was determined by melt quenching the crystalline drugs to determine their respective critical cooling rate. The inherent supersaturation potential of the drugs in FaSSIF was determined by a solvent shift method where the respective drugs were dissolved in dimethyl sulfoxide and then added to FaSSIF. This study showed that the poor glass formers naproxen, phenytoin, and probenecid could not supersaturate on their own, however for some drug:polymer combinations of naproxen and phenytoin, supersaturation of the drug was enabled by the polymer. In contrast, all of the good glass formers—cinnarizine, itraconazole, and ketoconazole—could supersaturate on their own. Furthermore, the maximum achievable concentration of the good glass formers was unaffected by the presence of a polymer.
An Evaluation of the Potential of NMR Spectroscopy and Computational Modelling Methods to Inform Biopharmaceutical Formulations
Authors: Pandya Akash , Howard Mark J. , Zloh Mire , Dalby Paul A.
Published: September 2018

Protein-based therapeutics are considered to be one of the most important classes of pharmaceuticals on the market. The growing need to prolong stability of high protein concentrations in liquid form has proven to be challenging. Therefore, significant effort is being made to design formulations which can enable the storage of these highly concentrated protein therapies for up to 2 years. Currently, the excipient selection approach involves empirical high-throughput screening, but does not reveal details on aggregation mechanisms or the molecular-level effects of the formulations under storage conditions. Computational modelling approaches have the potential to elucidate such mechanisms, and rapidly screen in silico prior to experimental testing. Nuclear Magnetic Resonance (NMR) spectroscopy can also provide complementary insights into excipient–protein interactions. This review will highlight the underpinning principles of molecular modelling and NMR spectroscopy. It will also discuss the advancements in the applications of computational and NMR approaches in investigating excipient–protein interactions.
Academic Career Progression of Chinese-Origin Pharmacy Faculty Members in Western Countries
Authors: Zhang Weixiang , Zhong Hao , Wang Yitao , Chan Ging , Hu Yuanjia , Hu Hao , Ouyang Defang
Published: September 2018

Background: The field of Pharmacy education is experiencing a paucity of underrepresented minorities (URMs) faculty worldwide. The aim of this study is to investigate the current professional status of Chinese-origin pharmacy faculty members, who are considered as a good model of URMs at pharmacy academia in western countries, and identify the influencing factors to their academic career progression in academic careers. Methods: An online questionnaire was sent to Chinese-origin academic staffs at pharmacy schools in US, UK, Canada, Australia, and New Zealand. The survey comprised demographic information, educational background, and the influencing factors to academic career progression. Results: The vast majority of Chinese faculty members who worked in US were male. Individuals with junior academic title comprised the largest proportion. Over 75% of Chinese-origin pharmacy academics were involved in scientific disciplines (e.g., pharmaceutics, pharmacology, and medicinal chemistry). Usually, Chinese-origin academic members spent 4 years obtaining their first academic jobs after finishing PhD degree, and need 5–6 years to get academic promotion. The contributing factors of academic promotion were high quality publications and external funding. Conclusion: Our research offers a deep insight into academic career progression for URMs and give some valuable advice for their pharmacy academic paths.
Droplet-Assisted Microfluidic Fabrication and Characterization of Multifunctional Polysaccharide Microgels Formed by Multicomponent Reactions
Authors: Hauck Nicolas , Seixas Nalin , Centeno Silvia , Schlüßler Raimund , Cojoc Gheorghe , Müller Paul , Guck Jochen , Wöll Dominik , Wessjohann Ludger , Thiele Julian
Published: September 2018

Polysaccharide-based microgels have broad applications in multi-parametric cell cultures, cell-free biotechnology, and drug delivery. Multicomponent reactions like the Passerini three-component and the Ugi four-component reaction are shown in here to be versatile platforms for fabricating these polysaccharide microgels by droplet microfluidics with a narrow size distribution. While conventional microgel formation requires pre-modification of hydrogel building blocks to introduce certain functionality, in multicomponent reactions one building block can be simply exchanged by another to introduce and extend functionality in a library-like fashion. Beyond synthesizing a range of polysaccharide-based microgels utilizing hyaluronic acid, alginate and chitosan, exemplary in-depth analysis of hyaluronic acid-based Ugi four-component gels is conducted by colloidal probe atomic force microscopy, confocal Brillouin microscopy, quantitative phase imaging, and fluorescence correlation spectroscopy to elucidate the capability of microfluidic multicomponent reactions for forming defined polysaccharide microgel networks. Particularly, the impact of crosslinker amount and length is studied. A higher network density leads to higher Young’s moduli accompanied by smaller pore sizes with lower diffusion coefficients of tracer molecules in the highly homogeneous network, and vice versa. Moreover, tailored building blocks allow for crosslinking the microgels and incorporating functional groups at the same time as demonstrated for biotin-functionalized, chitosan-based microgels formed by Ugi four-component reaction. To these microgels, streptavidin-labeled enzymes are easily conjugated as shown for horseradish peroxidase (HRP), which retains its activity inside the microgels.
Diurnal Response of Sun-Induced Fluorescence and PRI to Water Stress in Maize Using a Near-Surface Remote Sensing Platform
Authors: Xu Shan , Liu Zhigang , Zhao Liang , Zhao Huarong , Ren Sanxue
Published: September 2018

Sun-induced Fluorescence (SIF) and Photochemical Reflectance Index (PRI) data were collected in the field over maize to study their diurnal responses to different water stresses at the canopy scale. An automated field spectroscopy system was used to obtain continuous and long-term measurements of maize canopy in four field plots with different irrigation treatments. This system collects visible to near-infrared spectra with a spectrometer, which provides a sub-nanometer spectral resolution in the spectral range of 480~850 nm. The red SIF (FR) and far red SIF (FFR) data were retrieved by Spectral Fitting Methods (SFM) in the O 2 -A band and O 2 -B band, respectively. In addition to PRI, Δ PRI values were derived from PRI by subtracting an early morning PRI value. Photosynthetic active radiation (PAR) data, the canopy fraction of absorbed PAR (fPAR), and the air/canopy temperature and photosystem II operating efficiency (YII) at the leaf scale were collected concurrently. In this paper, the diurnal dynamics of each parameter before and after watering at the jointing stage were compared. The results showed that (i) both FR and FFR decreased under water stress, but FR always peaked at noon, and the peak of FFR advanced with the increase in stress. Leaf folding and the increase in Non-photochemical Quenching (NPQ) are the main reasons for this trend. Leaf YII gradually decreased from 8:00 to 14:00 and then recovered. In drought, leaf YII was smaller and decreased more rapidly. Therefore, the fluorescence yield at both the leaf and canopy scale responded to water stress. (ii) As good indicators of changes in NPQ, diurnal PRI and Δ PRI data also showed specific decreases due to water stress. Δ PRI can eliminate the impact of canopy structure. Under water stress, Δ PRI decreased rapidly from 8:00 to 13:00, and the maximum range of this decrease was approximately 0.05. After 13:00, their values started to increase but could not recover to their morning level. (iii) Higher canopy-air temperature differences ( Δ T ) indicate that stomatal closure leads to an increase in leaf temperature, which maintains a higher state in the afternoon. In summary, to cope with water stress, both leaf folding and changes in physiology are activated. To monitor drought, SIF performs best around midday, and PRI is better after noon.
Radar Path Delay Effects in Volcanic Gas Plumes: The Case of Láscar Volcano, Northern Chile
Authors: Bredemeyer Stefan , Ulmer Franz-Georg , Hansteen Thor , Walter Thomas
Published: September 2018

Modern volcano monitoring commonly involves Interferometric Synthetic Aperture Radar (InSAR) measurements to identify ground motions caused by volcanic activity. However, InSAR is largely affected by changes in atmospheric refractivity, in particular by changes which can be attributed to the distribution of water (H2O) vapor in the atmospheric column. Gas emissions from continuously degassing volcanoes contain abundant water vapor and thus produce variations in the atmospheric water vapor content above and downwind of the volcano, which are notably well captured by short-wavelength X-band SAR systems. These variations may in turn cause differential phase errors in volcano deformation estimates due to excess radar path delay effects within the volcanic gas plume. Inversely, if these radar path delay effects are better understood, they may be even used for monitoring degassing activity, by means of the precipitable water vapor (PWV) content in the plume at the time of SAR acquisitions, which may provide essential information on gas plume dispersion and the state of volcanic and hydrothermal activity. In this work we investigate the radar path delays that were generated by water vapor contained in the volcanic gas plume of the persistently degassing Láscar volcano, which is located in the dry Atacama Desert of Northern Chile. We estimate water vapor contents based on sulfur dioxide (SO2) emission measurements from a scanning UV spectrometer (Mini-DOAS) station installed at Láscar volcano, which were scaled by H2O/SO2 molar mixing ratios obtained during a multi-component Gas Analyzer System (Multi-GAS) survey on the crater rim of the volcano. To calculate the water vapor content in the downwind portion of the plume, where an increase of water vapor is expected, we further applied a correction involving estimation of potential evaporation rates of water droplets governed by turbulent mixing of the condensed volcanic plume with the dry atmosphere. Based on these estimates we obtain daily average PWV contents inside the volcanic gas plume of 0.2–2.5 mm equivalent water column, which translates to a slant wet delay (SWD) in DInSAR data of 1.6–20 mm. We used these estimates in combination with our high resolution TerraSAR-X DInSAR observations at Láscar volcano, in order to demonstrate the occurrence of repeated atmospheric delay patterns that were generated by volcanic gas emissions. We show that gas plume related refractivity changes are significant and detectable in DInSAR measurements. Implications are two-fold: X-band satellite radar observations also contain information on the degassing state of a volcano, while deformation signals need to be interpreted with care, which has relevance for volcano observations at Láscar and for other sites worldwide.
Deep Learning-Based Automatic Clutter/Interference Detection for HFSWR
Authors: Zhang Ling , You Wei , Wu Q. M. Jonathan , Qi Shengbo , Ji Yonggang
Published: September 2018

High-frequency surface wave radar (HFSWR) plays an important role in wide area monitoring of the marine target and the sea state. However, the detection ability of HFSWR is severely limited by the strong clutter and the interference, which are difficult to be detected due to many factors such as random occurrence and complex distribution characteristics. Hence the automatic detection of the clutter and interference is an important step towards extracting them. In this paper, an automatic clutter and interference detection method based on deep learning is proposed to improve the performance of HFSWR. Conventionally, the Range-Doppler (RD) spectrum image processing method requires the target feature extraction including feature design and preselection, which is not only complicated and time-consuming, but the quality of the designed features is bound up with the performance of the algorithm. By analyzing the features of the target, the clutter and the interference in RD spectrum images, a lightweight deep convolutional learning network is established based on a faster region-based convolutional neural networks (Faster R-CNN). By using effective feature extraction combined with a classifier, the clutter and the interference can be automatically detected. Due to the end-to-end architecture and the numerous convolutional features, the deep learning-based method can avoid the difficulty and absence of uniform standard inherent in handcrafted feature design and preselection. Field experimental results show that the Faster R-CNN based method can automatically detect the clutter and interference with decent performance and classify them with high accuracy.
Highly Accurate Step Counting at Various Walking States Using Low-Cost Inertial Measurement Unit Support Indoor Positioning System
Authors: Pham Van Thanh , Nguyen Duc Anh , Dang Nhu Dinh , Pham Hong Hai , Tran Van An , Sandrasegaran Kumbesan , Tran Duc-Tan
Published: September 2018

Accurate step counting is essential for indoor positioning, health monitoring systems, and other indoor positioning services. There are several publications and commercial applications in step counting. Nevertheless, over-counting, under-counting, and false walking problems are still encountered in these methods. In this paper, we propose to develop a highly accurate step counting method to solve these limitations by proposing four features: Minimal peak distance, minimal peak prominence, dynamic thresholding, and vibration elimination, and these features are adaptive with the user’s states. Our proposed features are combined with periodicity and similarity features to solve false walking problem. The proposed method shows a significant improvement of 99.42% and 96.47% of the average of accuracy in free walking and false walking problems, respectively, on our datasets. Furthermore, our proposed method also achieves the average accuracy of 97.04% on public datasets and better accuracy in comparison with three commercial step counting applications: Pedometer and Weight Loss Coach installed on Lenovo P780, Health apps in iPhone 5s (iOS 10.3.3), and S-health in Samsung Galaxy S5 (Android 6.01).
Distance-Resolving Raman Radar Based on a Time-Correlated CMOS Single-Photon Avalanche Diode Line Sensor
Authors: Kekkonen Jere , Nissinen Jan , Kostamovaara Juha , Nissinen Ilkka
Published: September 2018

Remote Raman spectroscopy is widely used to detect minerals, explosives and air pollution, for example. One of its main problems, however, is background radiation that is caused by ambient light and sample fluorescence. We present here, to the best of our knowledge, the first time a distance-resolving Raman radar device that is based on an adjustable, time-correlated complementary metal-oxide-semiconductor (CMOS) single-photon avalanche diode line sensor which can measure the location of the target sample simultaneously with the normal stand-off spectrometer operation and suppress the background radiation dramatically by means of sub-nanosecond time gating. A distance resolution of 3.75 cm could be verified simultaneously during normal spectrometer operation and Raman spectra of titanium dioxide were distinguished by this system at distances of 250 cm and 100 cm with illumination intensities of the background of 250 lux and 7600 lux, respectively. In addition, the major Raman peaks of olive oil, which has a fluorescence-to-Raman signal ratio of 33 and a fluorescence lifetime of 2.5 ns, were distinguished at a distance of 30 cm with a 250 lux background illumination intensity. We believe that this kind of time-correlated CMOS single-photon avalanche diode sensor could pave the way for new compact distance-resolving Raman radars for application where distance information within a range of several metres is needed at the same time as a Raman spectrum.
Digital Learning in the UK: Sociological Reflections on an Unequal Marketplace
Authors: Perrotta Carlo
Published: September 2018

Focusing on the UK context, and drawing on freely available information about online learning and the underlying commercial agreements between institutions, Massively Open Online Course (MOOC) platforms and Online Program Management (OPM) companies, this article shows how digitization and universities’ global expansion strategies are involved in forms of transnational marketization. In particular, the article shows that the online learning marketplace in the UK shows signs of segmentation, with ‘premium’ offerings in the high-to-middle tier targeting socially advantaged students-as-consumers, and a bottom region of low-ranking institutions drifting towards low-grade ‘unbundled’ provision that targets middle-to-low income groups. The article argues that the current global landscape of online education is a shifting, unequal market place, and that more research is needed on how different groups from a range of socio-economic backgrounds successfully or unsuccessfully navigate an increasingly fragmented and ‘unbundled’ educational terrain.
Climate Vulnerability in Rainfed Farming: Analysis from Indian Watersheds
Authors: Sathyan Archana Raghavan , Funk Christoph , Aenis Thomas , Breuer Lutz
Published: September 2018

India ranks first among the rainfed agricultural countries in the world. The impact of changing climate threatens rainfed food production as well as the food security of millions of people in the tropics and subtropics. The Government of India initiated Watershed Development Programmes (WDPs) for the overall development of these areas. We, therefore, established a comprehensive, location-specific, bottom-up tool to analyse and compare the climate vulnerability of watershed areas. For this, we deducted a new Climate Vulnerability Index for Rainfed Tropics (CVIRFT) to evaluate the potential effectiveness of programmes to adapt to climate change impacts. The CVIRFT comprises of three dimensions of vulnerability, i.e., adaptive capacity, exposure and sensitivity. These dimensions consist of ten major components and 59 indicators with emphasis on rainfed farming and WDP interventions. To test the tool, we collected primary data through household surveys (n = 215, split among three watershed communities) in Kerala. We show that there were strong variations in the exposure dimension, moderate in sensitivity and negligible in adaptive capacity across the watersheds. After analysing the major components under the dimensions, we suggest focusing on policy orientation towards redesigning of the WDPs with emphasis to economic diversification, livelihood strategies, social networking coupled with stakeholder participation, natural resource management and risk spread through credit and insurance flexibility. The CVIRFT is replicable to similar physio-geographic areas of rainfed farming, with the refinement of indicators suited to the locality.
Crowdsourcing—A New Paradigm of Organizational Learning of Public Organizations
Authors: Lenart-Gansiniec Regina , Sułkowski Łukasz
Published: September 2018

Increasingly, it is postulated in the literature that crowdsourcing may be important for organizational learning. However, research in this area has only been conducted in the environment of mature and innovative Scandinavian organizations. Researchers omit public organizations in their deliberations. The aim of this article is to empirically identify the importance of crowdsourcing for the organizational learning of municipal offices, and thus to identify crowdsourcing as a new organizational learning paradigm. The considerations carried out to this aim are important because organizational learning is a prerequisite for running contemporary policies and ensuring sustainable development of public organizations. Studies subordinated to the implementation of the goals set were carried out using the analysis of a typical case study. Four municipal offices operating in Poland implementing four types of crowdsourcing according to the division made by J. Howe were chosen for the research object in a purposeful manner. It is worth noting that the results obtained not only confirm, but also complement the postulates in the subject area of knowledge. The implementation of research allows to recognize crowdsourcing as a new and fast developing paradigm of organizational learning.
Social Vulnerability Assessment Using Artificial Neural Network (ANN) Model for Earthquake Hazard in Tabriz City, Iran
Authors: Alizadeh Mohsen , Alizadeh Esmaeil , Asadollahpour Kotenaee Sara , Shahabi Himan , Beiranvand Pour Amin , Panahi Mahdi , Bin Ahmad Baharin , Saro Lee
Published: September 2018

This study presents the application of an artificial neural network (ANN) and geographic information system (GIS) for estimating the social vulnerability to earthquakes in the Tabriz city, Iran. Thereby, seven indicators were identified and used for earthquake vulnerability mapping, including population density, household density, employed density, unemployed density, and literate people. To obtain more accuracy in our analysis, all of the indicators were entered into a geographic information system (GIS). After the standardization of the data, an artificial neural network (ANN) model was applied for deriving a social vulnerability map (SVM) of different hazard classes for Tabriz city. The results showed that 0.77% of the total area was found to be very highly vulnerable. Very low vulnerability was recorded for 76.31% of the total study area. The comparison of data provided by (SVM) and the residential building vulnerability (RBV) of Tabriz city indicated the validity of the results obtained by ANN processes. Scatter plots are used to plot the data. These scatter plots indicate the existence of a strong positive relationship between the most vulnerable zones (1, 4, and 5) and the least (3, 7, and 9) of the SVM and RBV. The results highlight the importance of using social vulnerability study for defining seismic-risk mitigation policies, emergency management, and territorial planning in order to reduce the impacts of disasters.
Effect of Deposit Mobilization on the Financial Sustainability of Rural Saving and Credit Cooperatives: Evidence from Ethiopia
Authors: Duguma Girma Jirata , Han Jiqin
Published: September 2018

Increasing institutional capital through deposit mobilization keeps the cost of capital low, thus leading to financial sustainability. However, little is known about how deposit mobilization affects financial sustainability. Using balanced panel data of 166 rural savings and credit cooperatives (RUSACCOs) from Ethiopia over the period of 2014–2016, we investigated the effect of deposit mobilization on financial sustainability. The results of the panel regression estimates showed that, among the deposits mobilization variables, the deposit to loan ratio, deposit to total asset ratio, the volume of deposits, and demand deposit ratio had a significant direct impact on financial sustainability. The fixed effect regression result for interest rate spread showed that an inverse relationship existed between the interest rate spread and financial sustainability. Furthermore, according to our robust fixed effect regression results, among the control variables, the age of the institution and inflation rate affects financial sustainability. Contrary to our expectations, the number of members and the percentage of woman members were not significant. This may be attributed to the fact that some members were inactive for a long period. We suggest that RUSACCOs should focus on deposit mobilization specifically on demand deposits and keep the interest rate spread narrower to ensure their sustainability.
Ebola Virus Causes Intestinal Tract Architectural Disruption and Bacterial Invasion in Non-Human Primates
Authors: Reisler Ronald B. , Zeng Xiankun , Schellhase Christopher W. , Bearss Jeremy J. , Warren Travis K. , Trefry John C. , Christopher George W. , Kortepeter Mark G. , Bavari Sina , Cardile Anthony P.
Published: September 2018

In the 2014–2016 West Africa Ebola Virus (EBOV) outbreak, there was a significant concern raised about the potential for secondary bacterial infection originating from the gastrointestinal tract, which led to the empiric treatment of many patients with antibiotics. This retrospective pathology case series summarizes the gastrointestinal pathology observed in control animals in the rhesus EBOV-Kikwit intramuscular 1000 plaque forming unit infection model. All 31 Non-human primates (NHPs) exhibited lymphoid depletion of gut-associated lymphoid tissue (GALT) but the severity and the specific location of the depletion varied. Mesenteric lymphoid depletion and necrosis were present in 87% (27/31) of NHPs. There was mucosal barrier disruption of the intestinal tract with mucosal necrosis and/or ulceration most notably in the duodenum (16%), cecum (16%), and colon (29%). In the intestinal tract, hemorrhage was noted most frequently in the duodenum (52%) and colon (45%). There were focal areas of bacterial submucosal invasion in the gastrointestinal (GI) tract in 9/31 (29%) of NHPs. Only 2/31 (6%) had evidence of pancreatic necrosis. One NHP (3%) experienced jejunal intussusception which may have been directly related to EBOV. Immunofluorescence assays demonstrated EBOV antigen in CD68+ macrophage/monocytes and endothelial cells in areas of GI vascular injury or necrosis.