bluuebunny/crossref_metadata_2025 huggingface dataset:
Thrust and Hydrodynamic Efficiency of the Bundled Flagella
Authors: Danis Umit , Rasooli Reza , Chen Chia-Yuan , Dur Onur , Sitti Metin , Pekkan Kerem
Published: July 2019

The motility mechanism of prokaryotic organisms has inspired many untethered microswimmers that could potentially perform minimally invasive medical procedures in stagnant fluid regions inside the human body. Some of these microswimmers are inspired by bacteria with single or multiple helical flagella to propel efficiently and fast. For multiple flagella configurations, the direct measurement of thrust and hydrodynamic propulsion efficiency has been challenging due to the ambiguous mechanical coupling between the flow field and mechanical power input. To address this challenge and to compare alternative micropropulsion designs, a methodology based on volumetric velocity field acquisition is developed to acquire the key propulsive performance parameters from scaled-up swimmer prototypes. A digital particle image velocimetry (PIV) analysis protocol was implemented and experiments were conducted with the aid of computational fluid dynamics (CFD). First, this methodology was validated using a rotating single-flagellum similitude model. In addition to the standard PIV error assessment, validation studies included 2D vs. 3D PIV, axial vs. lateral PIV and simultaneously acquired direct thrust force measurement comparisons. Compatible with typical micropropulsion flow regimes, experiments were conducted both for very low and higher Reynolds (Re) number regimes (up to a Re number = 0.01) than that are reported in the literature. Finally, multiple flagella bundling configurations at 0°, 90° and 180° helical phase-shift angles were studied using scaled-up multiple concentric flagella thrust elements. Thrust generation was found to be maximal for the in-phase (0°) bundling configuration but with ~50% lower hydrodynamic efficiency than the single flagellum. The proposed measurement protocol and static thrust test-bench can be used for bio-inspired microscale propulsion methods, where direct thrust and efficiency measurement are required.
Analysis of Bacteriophages with Insulator-Based Dielectrophoresis
Authors: Coll De Peña Adriana , Mohd Redzuan Nurul Humaira , Abajorga Milky K. , Hill Nicole , Thomas Julie A. , Lapizco-Encinas Blanca H.
Published: July 2019

Bacterial viruses or phages have great potential in the medical and agricultural fields as alternatives to antibiotics to control nuisance populations of pathogenic bacteria. However, current analysis and purification protocols for phages tend to be resource intensive and have numbers of limitations, such as impacting phage viability. The present study explores the potential of employing the electrokinetic technique of insulator-based dielectrophoresis (iDEP) for virus assessment, separation and enrichment. In particular, the application of the parameter “trapping value” (Tv) is explored as a standardized iDEP signature for each phage species. The present study includes mathematical modeling with COMSOL Multiphysics and extensive experimentation. Three related, but genetically and structurally distinct, phages were studied: Salmonella enterica phage SPN3US, Pseudomonas aeruginosa phage ϕKZ and P. chlororaphis phage 201ϕ2-1. This is the first iDEP study on bacteriophages with large and complex virions and the results illustrate their virions can be successfully enriched with iDEP systems and still retain infectivity. In addition, our results indicate that characterization of the negative dielectrophoretic response of a phage in terms of Tv could be used for predicting individual virus behavior in iDEP systems. The findings reported here can contribute to the establishment of protocols to analyze, purify and/or enrich samples of known and unknown phages.
Glycan Utilisation and Function in the Microbiome of Weaning Infants
Authors: McKeen Starin , Young Wayne , Fraser Karl , Roy Nicole C. , McNabb Warren C.
Published: July 2019

Glycans are present exogenously in the diet, expressed and secreted endogenously by host cells, and produced by microbes. All of these processes result in them being available to the gut microbiome, firmly placing glycans at the interface of diet–microbe–host interactions. The most dramatic shift in dietary sources of glycans occurs during the transition from the milk-based neonatal diet to the diverse omnivorous adult diet, and this has profound effects on the composition of the gut microbiome, gene expression by microbes and host cells, mucin composition, and immune development from innate towards adaptive responses. Understanding the glycan-mediated interactions occurring during this transitional window may inform dietary recommendations to support gut and immune development during a vulnerable age. This review aims to summarise the current state of knowledge on dietary glycan mediated changes that may occur in the infant gut microbiome and immune system during weaning.
Constraining Mantle Heterogeneity beneath the South China Sea: A New Perspective on Magma Water Content
Authors: Wang Wei , Chu Fengyou , Wu Xichang , Li Zhenggang , Chen Ling , Li Xiaohu , Yan Yuanzi , Zhang Jie
Published: July 2019

The nature of upper mantle is important to understand the evolution of the South China Sea (SCS); thus, we need better constrains on its mantle heterogeneity. Magma water concentration is a good indicator, but few data have been reported. However, the rarity of glass and melt inclusions and the special genesis for phenocrysts in SCS basalts present challenges to analyzing magmatic water content. Therefore, it is possible to estimate the water variations through the characteristics of partial melting and magma crystallization. We evaluated variations in Fe depletion, degree of melt fractions, and mantle source composition along the fossil spreading ridge (FSR) using SCS basalt data from published papers. We found that lava from the FSR 116.2° E, FSR 117.7° E, and non-FSR regions can be considered normal lava with normal water content; in contrast, lava from the FSR 117° E-carbonatite and 114.9–115.0° E basalts have higher water content and show evidence of strong Fe depletion during the fractional crystallization after elimination of the effects of plagioclase oversaturation. The enriched water in the 117° E-carbonatite basalts is contained in carbonated silicate melts, and that in the 114.9–115.0° E basalts results from mantle contamination with the lower continental crust. The lava from the 117° E-normal basalt has much lower water content because of the lesser influence of the Hainan plume. Therefore, there must be a mantle source compositional transition area between the southwestern and eastern sub-basins of the SCS, which have different mantle evolution histories. The mantle in the west is more affected by contamination with continental materials, while that in the east is more affected by the Hainan mantle plume.
The Genetic Association between Quartz Vein- and Greisen-Type Mineralization at the Maoping W–Sn Deposit, Southern Jiangxi, China: Insights from Zircon and Cassiterite U–Pb Ages and Cassiterite Trace Element Composition
Authors: Chen Li-Li , Ni Pei , Dai Bao-Zhang , Li Wen-Sheng , Chi Zhe , Pan Jun-Yi
Published: July 2019

The large-scale Maoping W–Sn deposit in the Gannan metallogenic belt of the eastern Nanling Range, South China, spatially associated with the Maoping granite pluton, hosts total ore reserves of 103,000 t WO3 and 50,000 t Sn. Two different types of mineralization developed in this deposit: Upper quartz vein-type mineralization, mostly within the Cambrian metamorphosed sandstone and slate, and underneath greisen-type mineralization within the Maoping granite. Cassiterites from both types of mineralization coexist with wolframite. Here we report for the first time in situ U–Pb data on cassiterite and zircon of the Maoping deposit obtained by LA-ICP-MS. Cassiterite from quartz vein and greisen yielded weighted average 206Pb/238U ages of 156.8 ± 1.5 Ma and 156.9 ± 1.4 Ma, respectively, which indicates that the two types of mineralization formed roughly at the same time. In addition, the two mineralization ages are consistent with the emplacement age of the Maoping granite (159.0 ± 1.5 Ma) within error, suggesting a close temporal and genetic link between W–Sn mineralization and granitic magmatism. The two types of mineralization formed at the same magmatic-hydrothermal event. Cassiterite from both types of mineralization shows high Fe, Ta, and Zr contents with a low Zr/Hf ratio, suggesting that the ore-forming fluid should be derived from the highly differentiated Maoping granite pluton. Cassiterite in greisen has higher contents of Nb and Ta but a lower concentration of Ti compared with that in quartz vein, indicating that the formation temperature of greisen-type mineralization is little higher than that of quartz-vein-type mineralization.
Long-Lasting Anti-Inflammatory and Antinociceptive Effects of Acute Ammonium Glycyrrhizinate Administration: Pharmacological, Biochemical, and Docking Studies
Authors: Maione Francesco , Minosi Paola , Di Giannuario Amalia , Raucci Federica , Chini Maria Giovanna , De Vita Simona , Bifulco Giuseppe , Mascolo Nicola , Pieretti Stefano
Published: July 2019

The object of the study was to estimate the long-lasting effects induced by ammonium glycyrrhizinate (AG) after a single administration in mice using animal models of pain and inflammation together with biochemical and docking studies. A single intraperitoneal injection of AG was able to produce anti-inflammatory effects in zymosan-induced paw edema and peritonitis. Moreover, in several animal models of pain, such as the writhing test, the formalin test, and hyperalgesia induced by zymosan, AG administered 24 h before the tests was able to induce a strong antinociceptive effect. Molecular docking studies revealed that AG possesses higher affinity for microsomal prostaglandin E synthase type-2 compared to type-1, whereas it seems to locate better in the binding pocket of cyclooxygenase (COX)-2 compared to COX-1. These results demonstrated that AG induced anti-inflammatory and antinociceptive effects until 24–48 h after a single administration thanks to its ability to bind the COX/mPGEs pathway. Taken together, all these findings highlight the potential use of AG for clinical treatment of pain and/or inflammatory-related diseases.
A Redox-Switchable Colorimetric Probe for “Naked-Eye” Detection of Hypochlorous Acid and Glutathione
Authors: Han Qian , Zhou Fang , Wang Yue , Feng Huan , Meng Qingtao , Zhang Zhiqiang , Zhang Run
Published: July 2019

We report the development of a new colorimetric probe (L-ol) for investigations of the redox process regulated by hypochlorous acid (HOCl) and glutathione (GSH). The HOCl/GSH redox-switching cycle process was investigated in detail by UV-vis absorption spectroscopy, colorimetric analysis assay and high-resolution mass spectrometry (HRMS). The switchable absorbance responses were attributed to the HOCl-induced oxidation of the p-methoxyphenol unit to the benzoquinone derivative (L-one) and sequential reduction of L-one to hydroquinone (L-ol’) by GSH. In phosphate-buffered saline (PBS) buffer, the absorbance of L-ol at 619 nm underwent a remarkable bathochromic-shift, accompanied by a color change from pale yellow to blue in the presence of HOCl. With further addition of GSH, the absorbance of L-one exclusively recovered to the original level. Meanwhile, the blue-colored solution returned to the naive pale yellow color in the presence of GSH. The detection limits for HOCl and GSH were calculated to be 6.3 and 96 nM according to the IUPAC criteria. Furthermore, L-ol-loaded chromatography plates have been prepared and successfully applied to visualize and quantitatively analyze HOCl in several natural waters.
Application of Porphyrins in Antibacterial Photodynamic Therapy
Authors: Amos-Tautua Bamidele , Songca Sandile , Oluwafemi Oluwatobi
Published: July 2019

Antibiotics are commonly used to control, treat, or prevent bacterial infections, however bacterial resistance to all known classes of traditional antibiotics has greatly increased in the past years especially in hospitals rendering certain therapies ineffective. To limit this emerging public health problem, there is a need to develop non-incursive, non-toxic, and new antimicrobial techniques that act more effectively and quicker than the current antibiotics. One of these effective techniques is antibacterial photodynamic therapy (aPDT). This review focuses on the application of porphyrins in the photo-inactivation of bacteria. Mechanisms of bacterial resistance and some of the current ‘greener’ methods of synthesis of meso-phenyl porphyrins are discussed. In addition, significance and limitations of aPDT are also discussed. Furthermore, we also elaborate on the current clinical applications and the future perspectives and directions of this non-antibiotic therapeutic strategy in combating infectious diseases.
Associated Effects of Cadmium and Copper Alter the Heavy Metals Uptake by Melissa Officinalis
Authors: Adamczyk-Szabela Dorota , Lisowska Katarzyna , Romanowska-Duda Zdzisława , Wolf Wojciech M.
Published: July 2019

Lemon balm (Melissa officinalis) is a popular herb widely used in medicine. It is often cultivated in soils with substantial heavy metal content. Here we investigate the associated effects of cadmium and copper on the plant growth parameters augmented by the manganese, zinc, and lead uptake indicators. The concentration of all elements in soil and plants was determined by the HR-CS FAAS with the ContrAA 300 Analytik Jena spectrometer. Bioavailable and total forms calculated for all examined metals were augmented by the soil analyses. The index of chlorophyll content in leaves, the activity of net photosynthesis, stomatal conductance, transpiration rate, and intercellular concentration of CO2 were also investigated. Either Cd or Cu acting alone at high concentrations in soil are toxic to plants as indicated by chlorophyll indices and gas exchange parameters. Surprisingly, this effect was not observed when both metals were administered together. The sole cadmium or copper supplementations hampered the plant’s growth, lowered the leaf area, and altered the plant’s stem elongation. Analysis of variance showed that cadmium and copper treatments of lemon balm significantly influenced manganese, lead, and zinc concentration in roots and above ground parts.
Apoptosis Induction Pathway in Human Colorectal Cancer Cell Line SW480 Exposed to Cereal Phenolic Extracts
Authors: Rao Shiwangni , Chinkwo Kenneth , Santhakumar Abishek , Johnson Stuart , Blanchard Christopher
Published: July 2019

Cereal phenolic extracts have previously been investigated for their potential anticancer properties; however, the exact mechanisms involved in the inhibition of tumour growth are unclear. One possible mechanism is the induction of apoptosis which is characterised by cell shrinkage, protein fragmentation, and DNA degradation followed by rapid engulfment of cell debris by macrophages. This study examines the ability of phenolic extracts from four cereals: rice, barley, oats and sorghum to induce apoptosis on colorectal cancer cells SW480. Wholegrain extracts from pigmented varieties of red rice, purple rice, black sorghum, and brown sorghum showed a significant reduction in cancer cell proliferation. Morphological observation using APOPercentage™ dye indicated positive for apoptosis. Further analyses of Yunlu29 (rice), Shawaya Short Black 1 and IS1136 (sorghum) showed expression of p53 and confirmed activation of multiple caspases, specifically for caspase 3 and 7. Purple rice, on the other hand, did not upregulate caspase 3 and 7, hence, suggestive of cell cycle arrest. Therefore, phenolic compounds present in cereals such as pigmented rice and sorghum may suppress cancer cell proliferation through the activation of the apoptosis.
Isolation of 1-(3′,4′-Dihydroxyphenyl)-3-(2″,4″,6″-trihydroxyphenyl)-propan-2-ol from Grape Seed Extract and Evaluation of its Antioxidant and Antispasmodic Potential
Authors: Gleńsk Michał , Hurst William J. , Glinski Vitold B. , Bednarski Marek , Gliński Jan A.
Published: July 2019

HPLC profiling of phenolics in grape seed extracts revealed a prominent peak of an unknown substance with concentrations up to 5.3%. Spectroscopic data allowed the identification of the compound 1 as 1-(3′,4′-dihydroxyphenyl)-3-(2″,4″,6″-trihydroxyphenyl)-propan-2-ol. 1 is known to be produced from catechin and epicatechin through anaerobic bacteria from human, as well as the rat, intestines. It was hypothesized that the marc remaining after expression of juice from grapes became infested during storage, resulting in the production of 1. Because compound 1 is infrequently found in nature and has never been found in grape seeds, its presence may be considered a marker of an unwanted anaerobic bacterial process occurring during production. The antioxidant potential of 1 was determined by DPPH, ABTS, and FRAP (ferric reducing antioxidant power) assays and compared to the potential of the following compounds: phloroglucine, pyrogallol, gallic acid, catechin, and epicatechin. Furthermore, it was established that 1 significantly reduced guinea pig ileum contraction induced by histamine.
Densely Distributed Multiple Resonance Modes in a Fan-Shaped Plasmonic Nanostructure Demonstrated by FEM Simulations
Authors: Wang Qiong , Ouyang Zhengbiao , Liu Qiang , Lin Mi
Published: July 2019

Multiple resonance modes have important applications since they can provide multi-frequency operation for devices and bring great flexibility in practice. In this paper, based on a fan-shaped cavity coupled to a metal-isolator-metal (MIM) waveguide, a new kind of ultracompact plasmonic nanostructure is proposed to realize multiple resonance modes with dense distribution in a broad spectral range, and demonstrated through finite-element method (FEM) simulations. As many as ten resonance modes with an average interval of about 30 nm are obtained. They originate from the coexistence and interference of three types of basic modes in the fan-shaped cavity, i.e., the ring-waveguide modes, the modes in a ring array of periodic air grooves, and the metal-core-cavity modes. The dependence of resonance modes on structure parameters is investigated, which can provide an effective guide for choosing appropriate multiple-resonance-mode structures. Furthermore, by means of adjusting the geometrical asymmetry induced by the axial offset of the metal core in the fan-shaped cavity, the resonance modes can be effectively modulated, and some new modes appear because the wave path in the cavity is changed. The result proposes a novel way to create multiple resonance modes in plasmonic nanostructures, providing additional degrees of freedom for tailoring the resonance spectra and promising applications in various plasmonic devices, such as optical filters, ultrafast switches, biochemical sensors, and data storages.
The Synthesis of the Pomegranate-Shaped α-Fe2O3 Using an In Situ Corrosion Method of Scorodite and Its Gas-Sensitive Property
Authors: Wang Yang , Tang Xincun , Cao Shan , Chen Xi , Rong Zhihao
Published: July 2019

The release of hazardous gas increases with the development of industry. The research of gas-sensitive materials has attracted attention. Nanoscale iron oxide (α-Fe2O3) is one of the research hotspots of gas-sensitive materials because it is a cheap, non-toxic semiconductor material. In this study, pomegranate-shaped α-Fe2O3 was synthesized using an in situ corrosion method of scorodite. Spherical-shaped α-Fe2O3 nanoparticles were included in the octahedral shells. The forming process of the structure was analyzed by a variety of measurements. The shell was formed first through the deposition of Fe(OH)3, which was produced by hydrolyzing scorodite. Then, the corrosion was continued and Fe(OH)3 precipitation was produced below the shell. The particles aggregated and formed spheres. The pomegranate-shaped α-Fe2O3 was formed when the scorodite was hydrolyzed completely. The gas-sensing properties of α-Fe2O3 were investigated. The results showed that pomegranate-shaped α-Fe2O3 was responsive to a variety of gases, especially xylene. The value of Ra/Rg was 67.29 at 340 °C when the concentration of xylene was 1000 ppm. This indicated the pomegranate-shaped α-Fe2O3 has potential application as a xylene gas sensor.
Piceatannol Protects Human Retinal Pigment Epithelial Cells against Hydrogen Peroxide Induced Oxidative Stress and Apoptosis through Modulating PI3K/Akt Signaling Pathway
Authors: Hao Yiming , Liu Jie , Wang Ziyuan , Yu Liangli (Lucy) , Wang Jing
Published: July 2019

This study investigated the protective effect and the molecular mechanism of piceatannol on hydrogen peroxide (H2O2)-induced retinal pigment epithelium cell (ARPE-19) damage. Piceatannol treatment significantly inhibited H2O2-induced RPE cell death and reactive oxygen species (ROS) generation by 64.4% and 75.0%, respectively. Results of flow cytometry showed that H2O2-induced ARPE-19 cells apoptosis was ameliorated by piceatannol supplementation, along with decreased relative protein expressions of Bax/Bcl-2, Cleave-Caspase-3, and Cleave-PARP. Moreover, piceatannol treatment induced NF-E2-related factor 2 (Nrf2) signaling activation, which was evidenced by increased transcription of anti-oxidant genes, glutamate-cysteine ligase catalytic subunit (GCLc), SOD, and HO-1. Knockdown of Nrf2 through targeted siRNA alleviated piceatannol-mediated HO-1 transcription, and significantly abolished piceatannol-mediated cytoprotection. LY294002 (PI3K inhibitor) dramatically blocked piceatannol-mediated increasing of Nrf2 nuclear translocation, HO-1 expression, and cytoprotective activity, indicating the involvement of PI3K/Akt pathway in the cytoprotective effect of piceatannol. The results from this suggest the potential of piceatannol in reducing the risk of age-related macular degeneration.
Life after Harvest: Circadian Regulation in Photosynthetic Pigments of Rocket Leaves during Supermarket Storage Affects the Nutritional Quality
Authors: Ruiz de Larrinaga Lorena , Resco de Dios Victor , Fabrikov Dmitri , Guil-Guerrero José Luis , Becerril José María , García-Plazaola José Ignacio , Esteban Raquel
Published: July 2019

Vegetables, once harvested and stored on supermarket shelves, continue to perform biochemical adjustments due to their modular nature and their ability to retain physiological autonomy. They can live after being harvested. In particular, the content of some essential nutraceuticals, such as carotenoids, can be altered in response to environmental or internal stimuli. Therefore, in the present study, we wondered whether endogenous rhythms continue to operate in commercial vegetables and if so, whether vegetable nutritional quality could be altered by such cycles. Our experimental model consisted of rocket leaves entrained under light/darkness cycles of 12/12 h over 3 days, and then we examined free-run oscillations for 2 days under continuous light or continuous darkness, which led to chlorophyll and carotenoid oscillations in both constant conditions. Given the importance of preserving food quality, the existence of such internal rhythms during continuous conditions may open new research perspective in nutrition science. However, while chromatographic techniques employed to determine pigment composition are accurate, they are also time-consuming and expensive. Here we propose for the first time an alternative method to estimate pigment content and the nutritional quality by the use of non-destructive and in situ optical techniques. These results are promising for nutritional quality assessments.
Food Consumption in Adolescents and Young Adults: Age-Specific Socio-Economic and Cultural Disparities (Belgian Food Consumption Survey 2014)
Authors: Desbouys Lucille , De Ridder Karin , Rouche Manon , Castetbon Katia
Published: July 2019

A key issue in nutritional public health policies is to take into account social disparities behind health inequalities. The transition from adolescence toward adulthood is a critical period regarding changes in health behaviors. This study aimed to determine how consumption of four emblematic food groups (two to favor and two to limit) differed according to socio-economic and cultural characteristics of adolescents and young adults living in Belgium. Two non-consecutive 24-h dietary recalls were carried out in a nationally representative sample of 10–39 year old subjects (n = 1505) included in the Belgian food consumption survey 2014. Weighted daily mean consumption of “fruits and vegetables”, “whole grain bread and cereals”, “refined starchy food”, and “sugary sweetened beverages” (SSB) was calculated and explored in multivariable linear regressions stratified into four age groups. After adjustment, 10–13 year old adolescents living in less educated households daily consumed lower amounts of “fruits and vegetables” (adjusted mean: 165.6 g/day (95% CI: 125.3–206.0)) and “whole grain bread and cereals” (40.4 g/day (22.9–58.0)), and higher amounts of SSB (309.7 g/day (131.3–488.1) than adolescents of same ages living in more educated households (220.2 g/day (179.8–260.7); 59.0 g/day (40.3–77.8); and 157.8 g/day (1.7–314.0), respectively). The same trends were observed in older groups, along with strong consumption disparities according to region of residency, country of birth, and occupation, with specificities according to age. Our findings suggest the need to better explore such disparities by stage of transition to adulthood, and to adapt nutritional health programs.
Allomyrina dichotoma Larva Extract Ameliorates the Hepatic Insulin Resistance of High-Fat Diet-Induced Diabetic Mice
Authors: Kim Kyong , Bae Gong Deuk , Lee Minho , Park Eun-Young , Baek Dong Jae , Kim Chul Young , Jun Hee-Sook , Oh Yoon Sin
Published: July 2019

Allomyrina dichotoma larva is a nutritional-worthy future food resource and it contributes to multiple pharmacological functions. However, its antidiabetic effect and molecular mechanisms are not yet fully understood. Therefore, we investigated the hypolipidemic effect of A. dichotoma larva extract (ADLE) in a high-fat diet (HFD)-induced C57BL/6J mice model. Glucose tolerance and insulin sensitivity in HFD-induced diabetic mice significantly improved after ADLE administration for six weeks. The levels of serum triglyceride (TG), aspartate aminotransferase (AST), alanine transferase (ALT) activity, and lipid accumulation were increased in the liver of HFD-fed mice, but the levels were significantly reduced by the ADLE treatment. Moreover, hepatic fibrosis and inflammatory gene expression in the liver from HFD-treated mice were ameliorated by the ADLE treatment. Dephosphorylation of AMP-activated protein kinase (AMPK) by palmitate was inhibited in the ADLE treated HepG2 cells, and subsequently reduced expression of lipogenic genes, such as SREPBP-1c, ACC, and FAS were observed. The reduced expression of lipogenic genes and an increased phosphorylation of AMPK was also observed in the liver from diabetic mice treated with ADLE. In conclusion, ADLE ameliorates hyperlipidemia through inhibition of hepatic lipogenesis via activating the AMPK signaling pathway. These findings suggest that ADLE and its constituent bioactive compounds are valuable to prevent or treat hepatic insulin resistance in type 2 diabetes.
Selenized Plant Oil Is an Efficient Source of Selenium for Selenoprotein Biosynthesis in Human Cell Lines
Authors: Sonet Jordan , Mosca Maurine , Bierla Katarzyna , Modzelewska Karolina , Flis-Borsuk Anna , Suchocki Piotr , Ksiazek Iza , Anuszewska Elzbieta , Bulteau Anne-Laure , Szpunar Joanna , Lobinski Ryszard , Chavatte Laurent
Published: July 2019

Selenium is an essential trace element which is incorporated in the form of a rare amino acid, the selenocysteine, into an important group of proteins, the selenoproteins. Among the twenty-five selenoprotein genes identified to date, several have important cellular functions in antioxidant defense, cell signaling and redox homeostasis. Many selenoproteins are regulated by the availability of selenium which mostly occurs in the form of water-soluble molecules, either organic (selenomethionine, selenocysteine, and selenoproteins) or inorganic (selenate or selenite). Recently, a mixture of selenitriglycerides, obtained by the reaction of selenite with sunflower oil at high temperature, referred to as Selol, was proposed as a novel non-toxic, highly bioavailable and active antioxidant and antineoplastic agent. Free selenite is not present in the final product since the two phases (water soluble and oil) are separated and the residual water-soluble selenite discarded. Here we compare the assimilation of selenium as Selol, selenite and selenate by various cancerous (LNCaP) or immortalized (HEK293 and PNT1A) cell lines. An approach combining analytical chemistry, molecular biology and biochemistry demonstrated that selenium from Selol was efficiently incorporated in selenoproteins in human cell lines, and thus produced the first ever evidence of the bioavailability of selenium from selenized lipids.
Longitudinal Analysis of Macronutrient Composition in Preterm and Term Human Milk: A Prospective Cohort Study
Authors: Fischer Fumeaux Céline J. , Garcia-Rodenas Clara L. , De Castro Carlos A. , Courtet-Compondu Marie-Claude , Thakkar Sagar K. , Beauport Lydie , Tolsa Jean-François , Affolter Michael
Published: July 2019

Background: Mother’s own milk is the optimal source of nutrients and provides numerous health advantages for mothers and infants. As they have supplementary nutritional needs, very preterm infants may require fortification of human milk (HM). Addressing HM composition and variations is essential to optimize HM fortification strategies for these vulnerable infants. Aims: To analyze and compare macronutrient composition in HM of mothers lactating very preterm (PT) (28 0/7 to 32 6/7 weeks of gestational age, GA) and term (T) infants (37 0/7 to 41 6/7 weeks of GA) over time, both at similar postnatal and postmenstrual ages, and to investigate other potential factors of variations. Methods: Milk samples from 27 mothers of the PT infants and 34 mothers of the T infants were collected longitudinally at 12 points in time during four months for the PT HM and eight points in time during two months for the T HM. Macronutrient composition (proteins, fat, and lactose) and energy were measured using a mid-infrared milk analyzer, corrected by bicinchoninic acid (BCA) assay for total protein content. Results: Analysis of 500 HM samples revealed large inter- and intra-subject variations in both groups. Proteins decreased from birth to four months in the PT and the T HM without significant differences at any postnatal time point, while it was lower around term equivalent age in PT HM. Lactose content remained stable and comparable over time. The PT HM contained significantly more fat and tended to be more caloric in the first two weeks of lactation, while the T HM revealed higher fat and higher energy content later during lactation (three to eight weeks). In both groups, male gender was associated with more fat and energy content. The gender association was stronger in the PT group, and it remained significant after adjustments. Conclusion: Longitudinal measurements of macronutrients compositions of the PT and the T HM showed only small differences at similar postnatal stages in our population. However, numerous differences exist at similar postmenstrual ages. Male gender seems to be associated with a higher content in fat, especially in the PT HM. This study provides original information on macronutrient composition and variations of HM, which is important to consider for the optimization of nutrition and growth of PT infants.
Interplay between Attenuation- and Virulence-Factors of Babesia bovis and Their Contribution to the Establishment of Persistent Infections in Cattle
Authors: Gallego-Lopez Gina M. , Cooke Brian M. , Suarez Carlos E.
Published: July 2019

Bovine babesiosis is an acute and persistent tick-borne global disease caused mainly by the intraerythrocytic apicomplexan parasites Babesia bovis and B. bigemina. B. bovis infected erythrocytes sequester in blood capillaries of the host (cytoadhesion), causing malaria-like neurological signs. Cytoadhesion and antigenic variation in B. bovis are linked to the expression of members of the Variant Erythrocyte Surface Antigen (VESA) gene family. Animals that survive acute B. bovis infection and those vaccinated with attenuated strains remain persistently infected, suggesting that B. bovis parasites use immune escape mechanisms. However, attenuated B. bovis parasites do not cause neurological signs in vaccinated animals, indicating that virulence or attenuation factors play roles in modulating parasite virulence phenotypes. Artificial overexpression of the SBP2t11 protein, a defined attenuation factor, was associated with reduced cytoadhesion, suggesting a role for this protein as a key modulator of virulence in the parasite. Hereby, we propose a model that might be functional in the modulation of B. bovis virulence and persistence that relies on the interplay among SBP2t, VESA proteins, cytoadhesion, and the immune responses of the host. Elucidation of mechanisms used by the parasite to establish persistent infection will likely contribute to the design of new methods for the control of bovine babesiosis.
Development of Bioinspired Gelatin and Gelatin/Chitosan Bilayer Hydrofilms for Wound Healing
Authors: Garcia-Orue Itxaso , Santos-Vizcaino Edorta , Etxabide Alaitz , Uranga Jone , Bayat Ardeshir , Guerrero Pedro , Igartua Manoli , de la Caba Koro , Hernandez Rosa
Published: July 2019

In the current study, we developed a novel gelatin-based bilayer wound dressing. We used different crosslinking agents to confer unique properties to each layer, obtaining a bioinspired multifunctional hydrofilm suitable for wound healing. First, we produced a resistant and non-degradable upper layer by lactose-mediated crosslinking of gelatin, which provided mechanical support and protection to overall design. For the lower layer, we crosslinked gelatin with citric acid, resulting in a porous matrix with a great swelling ability. In addition, we incorporated chitosan into the lower layer to harness its wound healing ability. FTIR and SEM analyses showed that lactose addition changed the secondary structure of gelatin, leading to a more compact and smoother structure than that obtained with citric acid. The hydrofilm was able to swell 384.2 ± 57.2% of its dry weight while maintaining mechanical integrity. Besides, its water vapour transmission rate was in the range of commercial dressings (1381.5 ± 108.6 g/m2·day). In vitro, cytotoxicity assays revealed excellent biocompatibility. Finally, the hydrofilm was analysed through an ex vivo wound healing assay in human skin. It achieved similar results to the control in terms of biocompatibility and wound healing, showing suitable characteristics to be used as a wound dressing.
Characterization of a Reservoir-Style Implant for Sustained Release of Tenofovir Alafenamide (TAF) for HIV Pre-Exposure Prophylaxis (PrEP)
Authors: Johnson Leah M. , Krovi Sai Archana , Li Linying , Girouard Natalie , Demkovich Zach R. , Myers Daniel , Creelman Ben , van der Straten Ariane
Published: July 2019

Long-acting (LA) HIV pre-exposure prophylaxis (PrEP) offers the potential to improve adherence by lowering the burden of daily or on-demand regimens of antiretroviral (ARV) drugs. This paper details the fabrication and in vitro performance of a subcutaneous and trocar-compatible implant for the LA delivery of tenofovir alafenamide (TAF). The reservoir-style implant comprises an extruded tube of a biodegradable polymer, poly(ε-caprolactone) (PCL), filled with a formulation of TAF and castor oil excipient. Parameters that affect the daily release rates of TAF are described, including the surface area of the implant, the thickness of the PCL tube walls (between 45 and 200 µm), and the properties of the PCL (e.g., crystallinity). In vitro studies show a linear relationship between daily release rates and surface area, demonstrating a membrane-controlled release mechanism from extruded PCL tubes. Release rates of TAF from the implant are inversely proportional to the wall thickness, with release rates between approximately 0.91 and 0.15 mg/day for 45 and 200 µm, respectively. The sustained release of TAF at 0.28 ± 0.06 mg/day over the course of 180 days in vitro was achieved. Progress in the development of this implant platform addresses the need for new biomedical approaches to the LA delivery of ARV drugs.
The HKT Transporter Gene from Arabidopsis, AtHKT1;1, Is Dominantly Expressed in Shoot Vascular Tissue and Root Tips and Is Mild Salt Stress-Responsive
Authors: Tada Yuichi
Published: July 2019

The Arabidopsis high-affinity K+ transporter (AtHKT1;1) plays roles in salt tolerance by unloading Na+ from the root xylem to the xylem parenchyma cells and/or uploading Na+ from the shoot/leaf xylem to the xylem parenchyma cells. To use this promoter for the molecular breeding of salt-tolerant plants, I evaluated the expression profile of the AtHKT1;1 promoter in detail. Approximately 1.1 kbp of sequence upstream from the start codon of AtHKT1;1 was polymerase chain reaction (PCR)-amplified, fused to the β-glucuronidase (GUS) gene, and introduced into Arabidopsis. The resultant transformants were evaluated under nonstressed and salt-stress conditions at the seedling and reproductive stages. Histochemical analysis showed that GUS activity was detected in vascular bundle tissue in roots, hypocotyls, petioles, leaves, and petals, and in root tips. GUS enzyme activity in shoots tended to be higher than that in roots at both stages. After treatment with 50 mM NaCl for 24 h, GUS transcription levels and GUS enzyme activity were enhanced in transgenic lines. These results indicate that the AtHKT1;1 promoter isolated in this study could be useful in expressing transgenes specifically in vascular tissue and root tips, and in a mild salt-stress-responsive manner. The data provide novel insights into the functions of AtHKT1;1.
Atypical Splicing Accompanied by Skipping Conserved Micro-Exons Produces Unique WRINKLED1, An AP2 Domain Transcription Factor in Rice Plants
Authors: Mano Fumiya , Aoyanagi Takuya , Kozaki Akiko
Published: July 2019

WRINKLED1 (WRI1), an AP2 domain transcription factor, is a master regulator of oil synthesis in plant seeds. Its closely related proteins (WRIs) are also involved in regulating the synthesis of fatty acids, which play a role in producing oils, membranes, and other important components in plants. We found two WRI1 genes, OsWRI1-1 and OsWRI1-2, and two additional WRI1 homologs, OsWRI3 and OsWRI4, in the rice genome. OsWRI1 was ubiquitously expressed in rice plants, including developing seeds. However, OsWRI3 was only significantly expressed in the leaf blade and OsWRI4 was not expressed at all. OsWRI1-1 contains amino acid sequence GCL instead of VYL, which is encoded by an independent 9-bp micro-exon that is conserved in many plant species. We found that the GCL sequence was produced by an atypical splicing accompanied by skipping of the micro-exon. Furthermore, OsWRI1-1 highly activates the transcription of the promoter for the biotin carboxyl transferase 2 gene in Arabidopsis, but its activity was reduced by amino acid replacement or deletion of the GCL sequence in a transient assay using Arabidopsis cells. Our results indicated that atypical splicing produced unique WRI1 in rice plants.
Emission Spectroscopic Characterization of a Helium Atmospheric Pressure Plasma Jet with Various Mixtures of Argon Gas in the Presence and the Absence of De-Ionized Water as a Target
Authors: Bolouki Nima , Hsieh Jang-Hsing , Li Chuan , Yang Yi-Zheng
Published: July 2019

A helium-based atmospheric pressure plasma jet (APPJ) with various flow rates of argon gas as a variable working gas was characterized by utilizing optical emission spectroscopy (OES) alongside the plasma jet. The spectroscopic characterization was performed through plasma exposure in direct and indirect interaction with and without de-ionized (DI) water. The electron density and electron temperature, which were estimated by Stark broadening of atomic hydrogen (486.1 nm) and the Boltzmann plot, were investigated as a function of the flow rate of argon gas. The spectra obtained by OES indicate that the hydroxyl concentrations reached a maximum value in the case of direct interaction with DI water as well as upstream of the plasma jet for all cases. The relative intensities of hydroxyl were optimized by changing the flow rate of argon gas.
Synthesis and Acoustic Study of a New Tung Oil-Based Polyurethane Composite Foam with the Addition of Miscanthus Lutarioriparius
Authors: Ji Yangjie , Chen Shuming , Cheng Yabing
Published: July 2019

Polyurethane foam is commonly used in the automobile industry due to its favorable acoustic performances. In this study, a new tung oil-based polyurethane composite foam (TOPUF) was prepared by a one-step method. Different forms and contents of miscanthus lutarioriparius (ML) were used in TOPUF for improving acoustic performance. Polyurethane foams were characterized by means of Fourier transform infrared and SEM. The acoustic properties and mechanical properties of TOPUF, obtained with ML, were determined and compared with pure petroleum-based polyurethane foam. The results illustrate that the modification of TOPUF with the ML has a positive effect on the acoustic and mechanical properties in comparison to the unmodified foam. TOPUF obtained with ML powders has better acoustic performance than that obtained with ML strips. The optimum acoustic performance is achieved at the filler content of 0.3 wt%. The average sound absorption coefficient and transmission loss can reach 0.518, and 19.05 dB, respectively.
Deep Learning-Based Pose Estimation of Apples for Inspection in Logistic Centers Using Single-Perspective Imaging
Authors: Giefer Lino Antoni , Arango Castellanos Juan Daniel , Babr Mohammad Mohammadzadeh , Freitag Michael
Published: July 2019

Fruit packaging is a time-consuming task due to its low automation level. The gentle handling required by some kinds of fruits and their natural variations complicates the implementation of automated quality controls and tray positioning for final packaging. In this article, we propose a method for the automatic localization and pose estimation of apples captured by a Red-Green-Blue (RGB) camera using convolutional neural networks. Our pose estimation algorithm uses a cascaded structure composed of two independent convolutional neural networks: one for the localization of apples within the images and a second for the estimation of the three-dimensional rotation of the localized and cropped image area containing an apple. We used a single shot multi-box detector to find the bounding boxes of the apples in the images. Lie algebra is used for the regression of the rotation, which represents an innovation in this kind of application. We compare the performances of four different network architectures and show that this kind of representation is more suitable than using state-of-the-art quaternions. By using this method, we achieved a promising accuracy for the rotation regression of 98.36%, considering an error range lower than 15 degrees, forming a base for the automation of fruit packing systems.
Utility Paths Combination in HEN for Energy Saving and CO2 Emission Reduction
Authors: Osman Abdelbagi , Eltayeb Mohanad , Rajab Fahd
Published: July 2019

Energy demand and flue gas emissions, namely carbon dioxide (CO2) associated with the industrial revolution have exhibited a continuous rise. Several approaches were introduced recently to mitigate energy consumption and CO2 emissions by either grass root design or retrofit of existing heat exchanger networks (HEN) in chemical process plants. In this work, a combinatorial approach of path combination is used to generate several options for heat recovery enhancement in HEN. The options are applied to successively shift heat load from HEN utilities using combined utility paths at different heat recovery approach temperature (HRAT) considering exchangers pressure drop. Industrial case study for HEN of the preheat train in crude oil distillation unit from the literature is used to demonstrate the approach. The obtained results have been studied economically using the cost targeting of Pinch Technology. As a result, both external energy usage and CO2 emissions have been reduced from a heater device in HEN by 20% and 17%, respectively, with a payback of less than one year.
DRAS-TIC Linked Data: Evenly Distributing the Past
Authors: Jansen Gregory , Coburn Aaron , Soroka Adam , Thomas Will , Marciano Richard
Published: July 2019

Memory institutions must be able to grow a fully-functional repository incrementally as collections grow, without expensive enterprise storage, massive data migrations, and the performance limits that stem from the vertical storage strategies. The Digital Repository at Scale that Invites Computation (DRAS-TIC) Fedora research project, funded by a two-year National Digital Platform grant from the Institute for Museum and Library Services (IMLS), is producing open-source software, tested cluster configurations, documentation, and best-practice guides that enable institutions to manage linked data repositories with petabyte-scale collections reliably. DRAS-TIC is a research initiative at the University of Maryland (UMD). The first DRAS-TIC repository system, named Indigo, was developed in 2015 and 2016 through a collaboration between U.K.-based storage company, Archive Analytics Ltd., and the UMD iSchool Digital Curation Innovation Center (DCIC), through funding from an NSF DIBBs (Data Infrastructure Building Blocks) grant (NCSA “Brown Dog”). DRAS-TIC Indigo leverages industry standard distributed database technology, in the form of Apache Cassandra, to provide open-ended scaling of repository storage without performance degradation. With the DRAS-TIC Fedora initiative, we make use of the Trellis Linked Data Platform (LDP), developed by Aaron Coburn at Amherst College, to add the LDP API over similar Apache Cassandra storage. This paper will explain our partner use cases, explore the system components, and showcase our performance-oriented approach, with the most emphasis given to performance measures available through the analytical dashboard on our testbed website.
A Survey of Attacks Against Twitter Spam Detectors in an Adversarial Environment
Authors: Imam Niddal H. , Vassilakis Vassilios G.
Published: July 2019

Online Social Networks (OSNs), such as Facebook and Twitter, have become a very important part of many people’s daily lives. Unfortunately, the high popularity of these platforms makes them very attractive to spammers. Machine learning (ML) techniques have been widely used as a tool to address many cybersecurity application problems (such as spam and malware detection). However, most of the proposed approaches do not consider the presence of adversaries that target the defense mechanism itself. Adversaries can launch sophisticated attacks to undermine deployed spam detectors either during training or the prediction (test) phase. Not considering these adversarial activities at the design stage makes OSNs’ spam detectors vulnerable to a range of adversarial attacks. Thus, this paper surveys the attacks against Twitter spam detectors in an adversarial environment, and a general taxonomy of potential adversarial attacks is presented using common frameworks from the literature. Examples of adversarial activities on Twitter that were discovered after observing Arabic trending hashtags are discussed in detail. A new type of spam tweet (adversarial spam tweet), which can be used to undermine a deployed classifier, is examined. In addition, possible countermeasures that could increase the robustness of Twitter spam detectors to such attacks are investigated.