bluuebunny/crossref_metadata_2025 huggingface dataset:
Efficient Charge Carrier Separation in l-Alanine Acids Derived N-TiO2 Nanospheres: The Role of Oxygen Vacancies in Tetrahedral Ti4+ Sites
Authors: Chen Yongjuan , Luo Xiu , Luo Yao , Xu Peiwen , He Jiao , Jiang Liang , Li Junjie , Yan Zhiying , Wang Jiaqiang
Published: May 2019

N-doped TiO2 with oxygen vacancies exhibits many advantages for photocatalysis, such as enhanced visible light absorbency, inhibition of the photogenerated charge carrier recombination, etc. However, preparation of N-doped TiO2 with oxygen vacancies under mild conditions is still a challenge. Herein, N-doped TiO2 nanospheres with tetrahedral Ti4+ sites were synthesized by using dodecylamine as template and assisted by l-alanine acids. The obtained samples were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and UV–Vis diffuse reflectance spectra (UV–Vis DRS). It was found that the dodecylamine as a neutral surfactant controlled the structure of TiO2 spherical, while l-alanine acids provided a nitrogen source. The existence of tetrahedral Ti4+ sites in N-doped TiO2 was also confirmed. The N-doped TiO2 sample with tetrahedral Ti4+ sites exhibited significantly improved photocatalytic performance for degradation of methylene blue solution under UV light or visible light irradiation. A combined time-resolved infrared (IR) spectroscopy study reveals that the enhanced photocatalytic performance could be attributed to a large amount of photogenerated charge carriers and efficient charge separation. It is demonstrated that the shallow donor state produced by oxygen vacancies of tetrahedral Ti4+ sites can effectively promote separation of charge carriers besides capturing electrons.
Versatile Mode-Locked Operations in an Er-Doped Fiber Laser with a Film-Type Indium Tin Oxide Saturable Absorber
Authors: Guo Quanxin , Pan Jie , Li Dengwang , Shen Yiming , Han Xile , Gao Jinjuan , Man Baoyuan , Zhang Huanian , Jiang Shouzhen
Published: May 2019

We demonstrate the generation of versatile mode-locked operations in an Er-doped fiber laser with an indium tin oxide (ITO) saturable absorber (SA). As an epsilon-near-zero material, ITO has been only used to fashion a mode-locked fiber laser as an ITO nanoparticle-polyvinyl alcohol SA. However, this type of SA cannot work at high power or ensure that the SA materials can be transmitted by the light. Thus, we covered the end face of a fiber with a uniform ITO film using the radio frequency magnetron sputtering technology to fabricate a novel ITO SA. Using this new type of SA, single-wavelength pulses, dual-wavelength pulses, and triple-wavelength multi-pulses were achieved easily. The pulse durations of these mode-locked operations were 1.67, 6.91, and 1 ns, respectively. At the dual-wavelength mode-locked state, the fiber laser could achieve an output power of 2.91 mW and a pulse energy of 1.48 nJ. This study reveals that such a proposed film-type ITO SA has excellent nonlinear absorption properties, which can promote the application of ITO film for ultrafast photonics.
Grouping of Poorly Soluble Low (Cyto)Toxic Particles: Example with 15 Selected Nanoparticles and A549 Human Lung Cells
Authors: Kononenko Veno , Warheit David B. , Drobne Damjana
Published: May 2019

Poorly soluble, low (cyto)toxic particles (PSLTs) are often regarded as one group, but it is important that these particles can be further differentiated based on their bioactivity. Currently, there are no biological endpoint based groupings for inhaled nanoparticles (NPs) that would allow us to subgroup PSLTs based on their mode of action. The aim of this study was to group NPs based on their cytotoxicity and by using the in vitro response of the endo-lysosomal system as a biological endpoint. The endo-lysosomal system is a main cellular loading site for NPs. An impaired endo-lysosomal system in alveolar type II cells may have serious adverse effects on the maintenance of pulmonary surfactant homeostasis. The 15 different NPs were tested with human lung adenocarcinoma (A549) cells. The highly soluble NPs were most cytotoxic. With respect to PSLTs, only three NPs increased the cellular load of acid and phospholipid rich organelles indicating particle biopersistence. All the rest PSLTs could be regarded as low hazardous. The presented in vitro test system could serve as a fast screening tool to group particles according to their ability to interfere with lung surfactant metabolism. We discuss the applicability of the suggested test system for bringing together substances with similar modes-of-action on lung epithelium. In addition, we discuss this approach as a benchmark test for the comparative assessment of biopersistence of PSLTs.
Temperature-Dependent Accommodation of Two Lattices of Largely Different Size during Growth
Authors: Sprodowski Carsten , Morgenstern Karina
Published: May 2019

If a material grows on another material with a largely different lattice constant, which of the two adapts for an energetically favorable growth? To tackle this question, we investigate the growth of Ag on Cu(111) by variable temperature scanning tunneling microscopy. The structures grown between 120 and 170 K are remarkably different from those grown between 200 and 340 K. The low-temperature structure is rectangular-like and consists of stacked rods, 7 to 8 Ag atoms long, which form a superstructure without long-range order. This structure covers the whole surface prior to nucleation of further layers. The high-temperature structure is hexagonal and consists of misfit dislocations forming 8 × 8 to 10 × 10 superstructures. For this structure, second layer nucleation sets in far before the closure of the first monolayer. While both structures are driven by the large lattice misfit between the two materials, the growing Ag layer adapts to the Cu surface at low temperature, while the Cu surface adapts to the growing Ag layer at higher temperature.
Dissolved Organic Matter Modulates Algal Oxidative Stress and Membrane System Responses to Binary Mixtures of Nano-Metal-Oxides (nCeO2, nMgO and nFe3O4) and Sulfadiazine
Authors: Zhang Fan , Ye Nan , Wang Se , Meng Yue , Fang Hao , Wang Zhuang , Wang De-Gao
Published: May 2019

Joint biomarker responses, oxidative stress and membrane systems, were determined for nano-metal-oxides (nMeO, i.e., nCeO2, nMgO, and nFe3O4) and sulfadiazine (SDZ) exposed at relevant low concentrations to two freshwater microalgae Scenedesmus obliquus and Chlorella pyrenoidosa. The impacts of dissolved organic matter (DOM) on the joint biomarker responses were also investigated. Results indicated that the presence of SDZ significantly decreased the level of intercellular reactive oxygen species (ROS) in the algal cells exposed to each nMeO. Reduction of cell membrane permeability (CMP) and mitochondrial membrane potential (MMP) in the algal cells was observed when the algae were exposed to the mixture of SDZ and the nMeO. The degree of reduction of the ROS level, CMP, and MMP significantly went down with the addition of DOM to a certain extent. Changes in cellular oxidative stress and membrane function depended on the types of both nMeO and algal species. This contribution provides an insight into the hazard assessment of a mixture consisting of emerging contaminants and DOM, as they can coexist in the aquatic environment.
Antibacterial Application on Staphylococcus aureus Using Antibiotic Agent/Zinc Oxide Nanorod Arrays/Polyethylethylketone Composite Samples
Authors: Chen Dave W. , Lee Kuan-Yi , Tsai Min-Hua , Lin Tung-Yi , Chen Chien-Hao , Cheng Kong-Wei
Published: May 2019

In this study, zinc oxide (ZnO) nanorod arrays as antibiotic agent carriers were grown on polyetheretherketone (PEEK) substrates using a chemical synthesis method. With the concentration of ammonium hydroxide in the precursor solution kept at 4 M, ZnO nanorod arrays with diameters in the range of 100–400 nm and a loading density of 1.7 mg/cm2 were grown onto the PEEK substrates. Their drug release profiles and the antibacterial properties of the antibiotic agent/ZnO/PEEK samples in the buffer solution were investigated. The results showed that the concentrations of antibiotic agents (ampicillin or vancomycin) released from the samples into the buffer solution were higher than the value of minimum inhibitory concentration of 90% for Staphylococcus aureus within the 96 h test. The bioactivities of ampicillin and vancomycin on substrates also showed around 40% and 80% on the Staphylococcus aureus, respectively. In the antibacterial activity test, sample with the suitable loading amount of antibiotic agent had a good inhibitory effect on the growth of Staphylococcus aureus.
Inhomogeneous Broadening of the Exciton Band in Optical Absorption Spectra of InP/ZnS Nanocrystals
Authors: Savchenko Sergey S. , Weinstein Ilya A.
Published: May 2019

In this work, we have simulated the processes of broadening the first exciton band in optical absorption spectra (OA) for InP/ZnS ensembles of colloidal quantum dots (QDs). A phenomenological model has been proposed that takes into account the effects of the exciton–phonon interaction, and allows one to analyze the influence of the static and dynamic types of atomic disorder on the temperature changes in the spectral characteristics in question. To vary the degree of static disorder in the model system, we have used a parameter δ, which characterizes the QD dispersion in size over the ensemble. We have also calculated the temperature shifts of the maxima and changes in the half-width for the exciton peaks in single nanocrystals (δ = 0), as well as for the integrated OA bands in the QD ensembles with different values of δ = 0.6–17%. The simulation results and the OA spectra data measured for InP/ZnS nanocrystals of 2.1 nm (δ = 11.1%) and 2.3 nm (δ = 17.3%), are in good mutual agreement in the temperature range of 6.5 K–RT. It has been shown that the contribution of static disorder to the observed inhomogeneous broadening of the OA bands for the QDs at room temperature exceeds 90%. The computational experiments performed indicate that the temperature shift of the maximum for the integrated OA band coincides with that for the exciton peak in a single nanocrystal. In this case, a reliable estimate of the parameters of the fundamental exciton–phonon interaction can be made. Simultaneously, the values of the specified parameters, calculated from the temperature broadening of the OA spectra, can be significantly different from the true ones due to the effects of static atomic disorder in real QD ensembles.
Synthesis of a Flower-Like g-C3N4/ZnO Hierarchical Structure with Improved CH4 Sensing Properties
Authors: Li Xiaojie , Li Yanwei , Sun Guang , Luo Na , Zhang Bo , Zhang Zhanying
Published: May 2019

In this paper, a hierarchical structure of graphite carbon nitride (g-C3N4) modified ZnO (g-C3N4/ZnO) was synthesized using a simple precipitation-calcination method. Through this method, g-C3N4 nanosheets with a controlled content were successfully decorated on the petals of flower-like ZnO. Various techniques were used to confirm the successful formation of the g-C3N4/ZnO hierarchical structure. The methane (CH4) sensing properties of g-C3N4/ZnO sensor were investigated. The result exhibited that after decorating ZnO with g-C3N4, the CH4 sensing performances of the fabricated sensor were remarkably improved. At the optimum operating temperature of 320 °C, the response of the sensor fabricated with CNZ-3 (the sample with an optimum content of g-C3N4) towards 1000 ppm CH4 was as high as 11.9 (Ra/Rg), which was about 2.2 times higher than that of the pure ZnO sensor (5.3). In addition, the CNZ-3 sensor also exhibited a fast response/recovery speed (15/28 s) and outstanding long-term stability. The enhancing CH4 sensing mechanism may be contributed to enlarged surface area, pore structure, and g-C3N4-ZnO n-n junction.
Batch-Fabricated α-Si Assisted Nanogap Tunneling Junctions
Authors: Banerjee Aishwaryadev , Khan Shakir-Ul Haque , Broadbent Samuel , Likhite Rugved , Looper Ryan , Kim Hanseup , Mastrangelo Carlos H.
Published: May 2019

This paper details the design, fabrication, and characterization of highly uniform batch-fabricated sidewall etched vertical nanogap tunneling junctions for bio-sensing applications. The device consists of two vertically stacked gold electrodes separated by a partially etched sacrificial spacer layer of sputtered α-Si and Atomic Layer Deposited (ALD) SiO2. A ~10 nm wide air-gap is formed along the sidewall by a controlled dry etch of the spacer. The thickness of the spacer layer can be tuned by adjusting the number of ALD cycles. The rigorous statistical characterization of the ultra-thin spacer films has also been performed. We fabricated nanogap electrodes under two design layouts with different overlap areas and spacer gaps, from ~4.0 nm to ~9.0 nm. Optical measurements reported an average non-uniformity of 0.46 nm (~8%) and 0.56 nm (~30%) in SiO2 and α-Si film thickness respectively. Direct tunneling and Fowler–Nordheim tunneling measurements were done and the barrier potential of the spacer stack was determined to be ~3.5 eV. I–V measurements showed a maximum resistance of 46 × 103 GΩ and the average dielectric breakdown field of the spacer stack was experimentally determined to be ~11 MV/cm.
Effect of AuPd Bimetal Sensitization on Gas Sensing Performance of Nanocrystalline SnO2 Obtained by Single Step Flame Spray Pyrolysis
Authors: Krivetskiy Valeriy , Zamanskiy Konstantin , Beltyukov Artemiy , Asachenko Andrey , Topchiy Maxim , Nechaev Mikhail , Garshev Alexey , Krotova Alina , Filatova Darya , Maslakov Konstantin , Rumyantseva Marina , Gaskov Alexander
Published: May 2019

Improvement of sensitivity, lower detection limits, stability and reproducibility of semiconductor metal oxide gas sensor characteristics are required for their application in the fields of ecological monitoring, industrial safety, public security, express medical diagnostics, etc. Facile and scalable single step flame spray pyrolysis (FSP) synthesis of bimetal AuPd sensitized nanocrystalline SnO2 is reported. The materials chemical composition, structure and morphology has been studied by XRD, XPS, HAADFSTEM, BET, ICP-MS techniques. Thermo-programmed reduction with hydrogen (TPR-H2) has been used for materials chemical reactivity characterization. Superior gas sensor response of bimetallic modified SnO2 towards wide concentration range of reducing (CO, CH4, C3H8, H2S, NH3) and oxidizing (NO2) gases compared to pure and monometallic modified SnO2 is reported for dry and humid gas detection conditions. The combination of facilitated oxygen molecule spillover on gold particles and electronic effect of Fermi level control by reoxidizing Pd-PdO clusters on SnO2 surface is proposed to give rise to the observed enhanced gas sensor performance.
An Easy Synthesis for Preparing Bio-Based Hybrid Adsorbent Useful for Fast Adsorption of Polar Pollutants
Authors: Sadraei Razieh , Paganini Maria Cristina , Calza Paola , Magnacca Giuliana
Published: May 2019

For the first time, γ-Al2O3 and Bio-Based Substances (BBS) hybrids (A-BBS) were prepared through a simple electrostatic interaction occurring between alumina, used as a support, and BBS (Bio-Based Substance from composted biowastes) carrying positive and negative charges, respectively. We evaluated the optimal amount of BBS to be immobilized on the support and the stability of the resulting A-BBS in order to use this novel hybrid material as an adsorbent for the removal of polar pollutants. Characterization was carried out by X-Ray Diffraction (XRD) for evaluating the crystal structure of the support, Fourier transform infrared spectroscopy (FT-IR) to evidence the presence of BBS on the hybrid material, thermogravimetric analysis (TGA) to measure the thermal stability of the hybrid materials and quantify the BBS amount immobilized on the support, N2 adsorption at 77 K for the evaluation of the surface area and porosity of the systems, Zeta potential measurements to evaluate the effect of BBS immobilization on the surface charge of the particles and choose the substrates possibly interacting with them. Firstly, we tested the adsorption capability of three samples differently coated with BBS toward cationic species considering various adsorbate/adsorbent ratio. Crystal Violet (CV) was chosen as model pollutant to compare the performance of the hybrid materials with those of other materials described in the literature. The adsorption data were modeled by Langmuir and Freundlich adsorption isotherms. Then, we studied the adsorption capability of the developed material towards molecules with different structures; for this purpose, two contaminants of emerging concerns (carbamazepine and atenolol) were tested. The results indicate that A-BBS could be applied in wastewater treatment for the removal of a significant amount of polar species. In addition, a comparison with literature data concerning CV adsorption was carried out in order to evaluate the environmental impact of synthetic routes used to prepare different adsorbents.
Infrared Polariscopy Imaging of Linear Polymeric Patterns with a Focal Plane Array
Authors: Honda Reo , Ryu Meguya , Moritake Masayuki , Balčytis Armandas , Mizeikis Vygantas , Vongsvivut Jitraporn , Tobin Mark J. , Appadoo Dominique , Li Jing-Liang , Ng Soon Hock , Juodkazis Saulius , Morikawa Junko
Published: May 2019

Polariscopy is demonstrated using hyperspectral imaging with a focal plane array (FPA) detector in the infrared (IR) spectral region under illumination by thermal and synchrotron light sources. FPA Fourier-transform IR (FTIR) imaging microspectroscopy is useful for monitoring real time changes at specific absorption bands when combined with a high brightness synchrotron source. In this study, several types of samples with unique structural motifs were selected and used for assessing the capability of polariscopy under this FPA-FTIR imaging technique. It was shown that the time required for polariscopy at IR wavelengths can be substantially reduced by the FPA-FTIR imaging approach. By using natural and laser fabricated polymers with sub-wavelength features, alignment of absorbing molecular dipoles and higher order patterns (laser fabricated structures) were revealed. Spectral polariscopy at the absorption peaks can reveal the orientation of sub-wavelength patterns (even when they are not spatially resolved) or the orientation of the absorbing dipoles.
The Fluorescent Quenching Mechanism of N and S Co-Doped Graphene Quantum Dots with Fe3+ and Hg2+ Ions and Their Application as a Novel Fluorescent Sensor
Authors: Yang Yue , Zou Tong , Wang Zhezhe , Xing Xinxin , Peng Sijia , Zhao Rongjun , Zhang Xu , Wang Yude
Published: May 2019

The fluorescence intensity of N, S co-doped graphene quantum dots (N, S-GQDs) can be quenched by Fe3+ and Hg2+. Density functional theory (DFT) simulation and experimental studies indicate that the fluorescence quenching mechanisms for Fe3+ and Hg2+ detection are mainly attributed to the inner filter effect (IFE) and dynamic quenching process, respectively. The electronegativity difference between C and doped atoms (N, S) in favor to introduce negative charge sites on the surface of N, S-GQDs leads to charge redistribution. Those negative charge sites facilitate the adsorption of cations on the N, S-GQDs’ surface. Atomic population analysis results show that some charge transfer from Fe3+ and Hg2+ to N, S-GQDs, which relate to the fluorescent quenching of N, S-GQDs. In addition, negative adsorption energy indicates the adsorption of Hg2+ and Fe2+ is energetically favorable, which also contributes to the adsorption of quencher ions. Blue fluorescent N, S-GQDs were synthesized by a facile one-pot hydrothermal treatment. Fluorescent lifetime and UV-vis measurements further validate the fluorescent quenching mechanism is related to the electron transfer dynamic quenching and IFE quenching. The as-synthesized N, S-GQDs were applied as a fluorescent probe for Fe3+ and Hg2+ detection. Results indicate that N, S-GQDs have good sensitivity and selectivity on Fe3+ and Hg2+ with a detection limit as low as 2.88 and 0.27 nM, respectively.
Nanoemulsion and Nanoliposome Based Strategies for Improving Anthocyanin Stability and Bioavailability
Authors: Chen Bing-Huei , Stephen Inbaraj Baskaran
Published: May 2019

Background: Anthocyanins, a flavonoid class of water-soluble pigments, are reported to possess several biological activities, including antioxidant, anti-inflammatory, and anti-cancer. However, anthocyanins are highly susceptible to degradation in high pH, light, heat, and oxygen during processing and storage. Conventional microencapsulation techniques fail to provide stability to anthocyanins under physiological environments mainly because of their large particle size as well as low zeta potential and encapsulation efficiency. Methods: Nanotechnology provides novel strategies for preparing nanoformulations to enhance the physicochemical stability of anthocyanins. Nanoemulsion and nanoliposome are the two most commonly used nanosystems in pharmaceutical and food-related fields. In this review, an overview of various nanoemulsion and nanoliposome systems reported recently for enhancing stability, bioavailability, and bioactivity of anthocyanins is presented. Results: Anthocyanin nanoemulsions with different oil, water, surfactant, and cosurfactant ratios were prepared from extracts of mangosteen peel, purple sweet potato, cranberry, red cabbage, blueberry, jaboticaba peel, and acai berry and evaluated for their antioxidant activity, enhancement of physicochemical stability, topical skin application, and urinary tract infection. Likewise, unilamellar and multilamellar nanoliposomes were prepared using different types and levels of lecithin without or with cholesterol from anthocyanin standards and extracts of Hibiscus sabdariffa, mulberry, elderberry, black carrot, and pistachio green hull for the evaluation of physicochemical and oxidative stability, in vitro bioaccessibility, and melanogenic activity, as well as protective effects against diabetes mellitus and cataract. Conclusion: This review provides an insight into the current nanotechnology updates on enhancement of anthocyanin stability and biological activity.
Sugar-Sweetened Beverages Contribute Significantly to College Students’ Daily Caloric Intake in Jordan: Soft Drinks Are Not the Major Contributor
Authors: Bawadi Hiba , Khataybeh Toqa , Obeidat Bayan , Kerkadi Abdelhamid , Tayyem Reema , Banks Angela , Subih Hadil
Published: May 2019

Sugar sweetened beverages (SSBs) are caloric-dense and associated with poor diet quality which may result in weight gain and obesity. Obesity is an independent risk factor for several chronic diseases. This study aimed to (1) assess the consumption level of SSBs among college students in Jordan and (2) examine the relationship of consumption level to body weight. The current study is a cross-sectional study conducted on 967 college students (55.3% males and 44.7% females). Consumption of SSBs was assessed using validated questionnaires. SSBs were classified into four major categories (hot drinks, fruit drinks, energy drinks, and soft drinks). Anthropometric measurements of the participants including body weight, height, and waist circumferences were recorded. Male students consumed more calories from SSBs compared to female students (p = 0.016). The mean contribution of SSBs to daily energy intake among college students was 480 kcal with the highest contribution from sugar sweetened hot drinks and fruit drinks. A significant positive relationship was found in BMI (p = 0.006) and waist circumference (p = 0.030) for participants consuming calories from SSBs. In conclusion, beverages with added sugar contribute substantially to the daily energy intake of college students in Jordan.
Sea Cucumber (Stichopus japonicas) F2 Enhanced TRAIL-Induced Apoptosis via XIAP Ubiquitination and ER Stress in Colorectal Cancer Cells
Authors: Kim Jung Lim , Park Seong Hye , Jeong Soyeon , Kim Bo Ram , Na Yoo Jin , Jo Min Jee , Jeong Yoon A , Yun Hye Kyeong , Kim Dae Yeong , Kim Bu Gyeom , You SangGuan , Oh Sang Cheul , Lee Dae-Hee
Published: May 2019

Natural products have shown great promise in sensitizing cells to TNF-related apoptosis-inducing ligand (TRAIL) therapy. Sea cucumber (SC) extracts possess antitumor activity, and hence their potential to sensitize colorectal cancer (CRC) cells to TRAIL therapy was evaluated. This study used Western blotting to evaluate the combination effects of SC and TRAIL in CRC, and determined the molecular mechanism underlying these effects. SC fractions and TRAIL alone did not affect apoptosis; however, combined treatment dramatically induced the apoptosis of CRC cells, but not of normal colon cells. Combined treatment induced the expression of apoptotic proteins (poly (ADP-ribose) polymerase (PARP), caspase 3, and 8), and this effect was markedly inhibited by the ubiquitination of X-linked inhibitor of apoptosis protein (XIAP). SC did not affect the mRNA levels, but it increased proteasomal degradation and ubiquitination of the XIAP protein. Furthermore, SC induced reactive oxygen species (ROS) production, thereby activating c-Jun N-terminal kinase (JNK) and endoplasmic reticulum (ER) stress-related apoptotic pathways in CRC. Altogether, our results demonstrate that the SC F2 fraction may sensitize CRC cells to TRAIL-induced apoptosis through XIAP ubiquitination and ER stress.
Bases for the Adequate Development of Nutritional Recommendations for Patients with Inflammatory Bowel Disease
Authors: Sáez-González Esteban , Mateos Beatriz , López-Muñoz Pedro , Iborra Marisa , Moret Inés , Nos Pilar , Beltrán Belén
Published: May 2019

Inflammatory bowel disease (IBD) is a chronic and relapsing inflammatory condition of the gastrointestinal tract; it is a heterogeneous and multifactorial disorder resulting from a complex interplay between genetic variation, intestinal microbiota, the host immune system and environmental factors such as diet, drugs, breastfeeding and smoking. The interactions between dietary nutrients and intestinal immunity are complex. There is a compelling argument for environmental factors such as diet playing a role in the cause and course of IBD, given that three important factors in the pathogenesis of IBD can be modulated and controlled by diet: intestinal microbiota, the immune system and epithelial barrier function. The aim of this review is to summarize the epidemiological findings regarding diet and to focus on the effects that nutrients exert on the intestinal mucosa–microbiota–permeability interaction. The nature of these interactions in IBD is influenced by alterations in the nutritional metabolism of the gut microbiota and host cells that can influence the outcome of nutritional intervention. A better understanding of diet–host–microbiota interactions is essential for unravelling the complex molecular basis of epigenetic, genetic and environmental interactions underlying IBD pathogenesis as well as for offering new therapeutic approaches for the treatment of IBD.
Enzymatic Hydrolysis of a Collagen Hydrolysate Enhances Postprandial Absorption Rate—A Randomized Controlled Trial
Authors: Skov Kathrine , Oxfeldt Mikkel , Thøgersen Rebekka , Hansen Mette , Bertram Hanne Christine
Published: May 2019

Collagen is characterized by its high content of glycine, proline and hydroxyproline, and is found to exert beneficial effects on joint pain related to activity and osteoarthritis. However, to exert any beneficial effects it is essential that collagen is optimally absorbed. This study aimed to investigate the postprandial absorption of collagen and elucidate the impact of an exogenous enzymatic hydrolysis on absorption rate and bioavailability. A randomized, blinded, cross-over study was conducted where ten healthy male subjects received either 35 g enzymatically hydrolyzed collagen protein (EHC), 35 g non-enzymatically hydrolyzed collagen protein (NC) or placebo (250 mL water) on three nonconsecutive days. Blood samples were drawn before, and up to 240 min following, ingestion and the blood metabolome was characterized by nuclear magnetic resonance (NMR)-based metabolomics. A significant increase in the plasma concentration of nearly all amino acids (AAs) was observed over a 240 min period for both EHC and NC. In addition, the absorption rate and bioavailability of glycine, proline and hydroxyproline were significantly higher for EHC (p < 0.05). In conclusion, ingestion of collagen hydrolysates increases postprandial plasma concentrations of AAs over a period of 240 min, and an enzymatic hydrolysis increases the absorption rate and bioavailability of the collagen-rich AAs glycine, proline and hydroxyproline.
Childhood Diarrhoea in the Eastern Mediterranean Region with Special Emphasis on Non-Typhoidal Salmonella at the Human–Food Interface
Authors: Harb Ali , O’Dea Mark , Abraham Sam , Habib Ihab
Published: May 2019

Diarrhoeal disease is still one of the most challenging issues for health in many countries across the Eastern Mediterranean region (EMR), with infectious diarrhoea being an important cause of morbidity and mortality, especially in children under five years of age. However, the understanding of the aetiological spectrum and the burden of enteric pathogens involved in diarrhoeal disease in the EMR is incomplete. Non-typhoidal Salmonella (NTS), the focus of this review, is one of the most frequently reported bacterial aetiologies in diarrhoeal disease in the EMR. Strains of NTS with resistance to antimicrobial drugs are increasingly reported in both developed and developing countries. In the EMR, it is now widely accepted that many such resistant strains are zoonotic in origin and acquire their resistance in the food-animal host before onward transmission to humans through the food chain. Here, we review epidemiological and microbiological aspects of diarrhoeal diseases among children in the EMR, with emphasis on the implication and burden of NTS. We collate evidence from studies across the EMR on the zoonotic exposure and antimicrobial resistance in NTS at the interface between human and foods of animal origin. This review adds to our understanding of the global epidemiology of Salmonella with emphasis on the current situation in the EMR.
The Ratio of Nasal Cannula Gas Flow to Patient Inspiratory Flow on Trans-nasal Pulmonary Aerosol Delivery for Adults: An in Vitro Study
Authors: Li Jie , Gong Lingyue , Fink James B.
Published: May 2019

Trans-nasal aerosol deposition during distressed breathing is higher than quiet breathing, and decreases as administered gas flow increases. We hypothesize that inhaled dose is related to the ratio of gas flow to patient inspiratory flow (GF:IF). An adult manikin (Laerdal) with a collecting filter placed at trachea was connected to a dual-chamber model lung, which was driven by a ventilator to simulate quiet and distressed breathing with different inspiratory flows. Gas flow was set at 5, 10, 20, 40 and 60 L/min. Albuterol (2.5mg in 1 mL) was nebulized by vibrating mesh nebulizer at the inlet of humidifier at 37 °C for each condition (n = 3). Drug was eluted from the filter and assayed with UV spectrophotometry (276 nm). GF:IF was the primary predictor of inhaled dose (p < 0.001). When the ratio was < 1.0, the inhaled dose was higher than ratio > 1.0 (21.8 ± 3.8% vs. 9.0 ± 3.7%, p < 0.001), and the inhaled dose was similar between quiet and distressed breathing (22.3 ± 5.0% vs. 21.3 ± 2.7%, p = 0.379). During trans-nasal aerosol delivery, GF:IF primarily affected the inhaled dose. Compared to the ratio above 1.0, the ratio below 1.0 produced a higher and more-consistent inhaled dose.
Using Service Blueprints to Visualize Pharmacy Innovations
Authors: Holdford David A.
Published: May 2019

Background: Applying the principles of service design can help pharmacists manage both the quality and patient perceptions of the services they provide. Service blueprints are a widely used service design tool that are rare in the healthcare literature. They can be used to design new services or revisit the design of established services. This paper describes service blueprints and their uses, and illustrates how to build one using an example. Methods: A blueprint is built for appointment-based medication synchronization services to illustrate the tool. Conclusions: Service blueprints permit pharmacists to better see and understand service processes. They clarify the process of service delivery and the roles of customers, service providers, and supporting services. They provide a way of depicting complex services in a concise visual way that communicates details at a glance. Pharmacists who utilize service blueprints can improve the consistency and quality of services provided, and they can increase the chance that every interaction with patients sends a positive message about the value of pharmacist services.
Impact of Dispensing Services in an Independent Community Pharmacy
Authors: Payne Kaleb , Unni Elizabeth J. , Jolley Benjamin
Published: May 2019

With approximately 300 prescriptions dispensed per day in a typical community pharmacy, several activities take place to ensure the safe dispensing of medicines. While some of these activities are common for all prescriptions, others need further activities such as prescription clarification. These activities are important to avoid any potential harm to the patient and improve medication adherence. The objective of this study was to measure the impact of these additional dispensing services in a community pharmacy by evaluating the documented patient notes. Two-hundred patients with annotations on their profiles between 1 July and 31 August 2018 were randomly selected and 322 notes were analyzed. The average number of notes per patient was 1.6. The majority of the notes were about contacting the patient/caregiver for prescription clarification (86.8%). When analyzed based on Medication Therapy Problems, 54.7% were related to adherence and 35.4% to safety. Using the cost saving estimate from the literature for each averted adverse event, these activities resulted in a minimum cost saving of $10,458. This study was able to show the positive impacts that everyday dispensing services in an independent community pharmacy have on ensuring the safe use of medication, thus potentially preventing adverse drug events and reducing health care costs.
Multifunctional Smart Optical Fibers: Materials, Fabrication, and Sensing Applications
Authors: Liu Zhengyong , Zhang Zhi , Tam Hwa-Yaw , Tao Xiaoming
Published: May 2019

This paper presents a review of the development of optical fibers made of multiple materials, particularly including silica glass, soft glass, polymers, hydrogels, biomaterials, Polydimethylsiloxane (PDMS), and Polyperfluoro-Butenylvinyleth (CYTOP). The properties of the materials are discussed according to their various applications. Typical fabrication techniques for specialty optical fibers based on these materials are introduced, which are mainly focused on extrusion, drilling, and stacking methods depending on the materials’ thermal properties. Microstructures render multiple functions of optical fibers and bring more flexibility in fiber design and device fabrication. In particular, micro-structured optical fibers made from different types of materials are reviewed. The sensing capability of optical fibers enables smart monitoring. Widely used techniques to develop fiber sensors, i.e., fiber Bragg grating and interferometry, are discussed in terms of sensing principles and fabrication methods. Lastly, sensing applications in oil/gas, optofluidics, and particularly healthcare monitoring using specialty optical fibers are demonstrated. In comparison with conventional silica-glass single-mode fiber, state-of-the-art specialty optical fibers provide promising prospects in sensing applications due to flexible choices in materials and microstructures.
Consistent Differences in Field Leaf Water-Use Efficiency among Soybean Cultivars
Authors: Bunce James
Published: May 2019

High intrinsic water-use efficiency (WUEi), the ratio of leaf photosynthesis to stomatal conductance, may be a useful trait in adapting crops to water-limited environments. In soybean, cultivar differences in stomatal response to vapor pressure deficit have not consistently translated into differences in WUEi in the field. In this study, six cultivars of soybeans previously shown to differ in WUEi in indoor experiments were grown in the field in Beltsville, Maryland, and tested for mid-day WUEi on nine clear days during the mid-seasons of two years. Measurement dates were chosen for diverse temperatures, and air temperatures ranged from 21 to 34 °C on the different dates. Air saturation deficits for water vapor ranged from 0.9 to 2.2 kPa. Corrected carbon isotope delta values for 13C (CID) were determined on mature, upper canopy leaves harvested during early pod filling each year. WUEi differed among cultivars in both years and the differences were consistent across measurement dates. Correlations between mean WUEi and CID were not significant in either year. It is concluded that consistent cultivar differences in WUEi exist in these soybean cultivars under field conditions, but that carbon isotope ratios may not be useful in identifying them because of cultivar differences in mesophyll conductance.
The Effect of Magnetic Field Strength and Geometry on the Deposition Rate and Ionized Flux Fraction in the HiPIMS Discharge
Authors: Hajihoseini Hamidreza , Čada Martin , Hubička Zdenek , Ünaldi Selen , Raadu Michael A. , Brenning Nils , Gudmundsson Jon Tomas , Lundin Daniel
Published: May 2019

We explored the effect of magnetic field strength | B | and geometry (degree of balancing) on the deposition rate and ionized flux fraction F flux in dc magnetron sputtering (dcMS) and high power impulse magnetron sputtering (HiPIMS) when depositing titanium. The HiPIMS discharge was run in two different operating modes. The first one we refer to as “fixed voltage mode” where the cathode voltage was kept fixed at 625 V while the pulse repetition frequency was varied to achieve the desired time average power (300 W). The second mode we refer to as “fixed peak current mode” and was carried out by adjusting the cathode voltage to maintain a fixed peak discharge current and by varying the frequency to achieve the same average power. Our results show that the dcMS deposition rate was weakly sensitive to variations in the magnetic field while the deposition rate during HiPIMS operated in fixed voltage mode changed from 30% to 90% of the dcMS deposition rate as | B | decreased. In contrast, when operating the HiPIMS discharge in fixed peak current mode, the deposition rate increased only slightly with decreasing | B | . In fixed voltage mode, for weaker | B | , the higher was the deposition rate, the lower was the F flux . In the fixed peak current mode, both deposition rate and F flux increased with decreasing | B | . Deposition rate uniformity measurements illustrated that the dcMS deposition uniformity was rather insensitive to changes in | B | while both HiPIMS operating modes were highly sensitive. The HiPIMS deposition rate uniformity could be 10% lower or up to 10% higher than the dcMS deposition rate uniformity depending on | B | and in particular the magnetic field topology. We related the measured quantities, the deposition rate and ionized flux fraction, to the ionization probability α t and the back attraction probability of the sputtered species β t . We showed that the fraction of the ions of the sputtered material that escape back attraction increased by 30% when | B | was reduced during operation in fixed peak current mode while the ionization probability of the sputtered species increased with increasing | B | , due to increased discharge current, when operating in fixed voltage mode.
Thermotropic Liquid-Crystalline and Light-Emitting Properties of Poly(pyridinium) Salts Containing Various Diamine Connectors and Hydrophilic Macrocounterions
Authors: Jo Tae Soo , Han Haesook , Bhowmik Pradip K. , Heinrich Benoît , Donnio Bertrand
Published: May 2019

A set of poly(pyridinium) salts containing various diamine moieties, as molecular connectors, and poly(ethyleneglycol)-4-nonylphenyl-3-sulfopropyl ether, thereafter referred to as “Macroion”, as the hydrophilic counterion, were prepared by metathesis reaction from the respective precursory tosylated poly(pyridinium)s in methanol. The structure of these ionic polymers was established by spectroscopy and chromatography techniques. The shape-persistent ionic poly(pyridinium) materials, inserting rigid or semi-rigid diamine spacers, display thermotropic liquid-crystalline properties from room-temperature up to their isotropization (in the temperature range around 160–200 °C). The nature of the LC phases is lamellar in both cases as identified by the combination of various complementary experimental techniques including DSC, POM and variable-temperature SAXS. The other polymers, inserting bulky or flexible spacers, only form room temperature viscous liquids. These new macromolecular systems can then be referred to as polymeric ionic liquid crystals (PILCs) and or polymeric ionic liquids (PILs). All the ionic polymers show excellent thermal stability, in the 260–330 °C temperature range as determined by TGA measurements, and a good solubility in common organic solvents as well as in water. Their optical properties were characterized in both solution and solid states by UV−Vis and photoluminescent spectroscopies. They emit blue or green light in both the states and exhibit a positive solvatochromic effect.
Development and Properties of Polymeric Nanocomposite Coatings
Authors: Nawaz Muddasir , Yusuf Noor , Habib Sehrish , Shakoor Rana Abdul , Ubaid Fareeha , Ahmad Zubair , Kahraman Ramazan , Mansour Said , Gao Wei
Published: May 2019

Polymeric-based nanocomposite coatings were synthesized by reinforcing epoxy matrix with titanium nanotubes (TNTs) loaded with dodecylamine (DOC). The performance of the developed nanocomposite coatings was investigated in corrosive environments to evaluate their anti-corrosion properties. The SEM/TEM, TGA, and FTIR analysis confirm the loading of the DOC into the TNTs. The UV-Vis spectroscopic analysis confirms the self-release of the inhibitor (DOC) in response to the pH change. The electrochemical impedance spectroscopic (EIS) analysis indicates that the synthesized nanocomposite coatings demonstrate superior anticorrosion properties at pH 2 as compared to pH 5. The improved anticorrosion properties of nanocomposite coatings at pH 2 can be attributed to the more effective release of the DOC from the nanocontainers. The superior performance makes polymeric nanocomposite coatings suitable for many industrial applications.
Soluble Polyimides Bearing (cis, trans)-Hydrogenated Bisphenol A and (trans, trans)-Hydrogenated Bisphenol A Moieties: Synthesis, Properties and the Conformational Effect
Authors: Mi Zhiming , Wang Shuai , Hou Ziwen , Liu Zhixiao , Jin Sizhuo , Wang Xiaowen , Wang Daming , Zhao Xiaogang , Zhang Yumin , Zhou Hongwei , Chen Chunhai
Published: May 2019

In this work, hydrogenated bisphenol A (HBPA) based dinitro mixed isomers (1a′ and 1a) were synthesized and separated via vacuum distillation under the monitor of DSC and 1H NMR. Corresponding diamines (2a′ and 2a) were separately polycondensed with five commercial dianhydrides via a two-step thermal imidization to obtain PI-(1′-5′) and PI-(1-5). All the polyimides could afford flexible, tough, and transparent films, and most of them were readily soluble not only in common polar solvents like DMAc, but also in low boiling point solvents such as chloroform. 1H NMR spectra of the polyimides demonstrated that HBPA moiety showed no conformation changes during the preparation of polymers. For a given dianhydride, PI-(1-5) exhibited better thermal stability than that of PI-(1′-5′), this can be attributed that the equatorial, equatorial C–O in PI-(1-5) promoted denser and more regular molecular chain stacking, as can be evidenced by the WAXD and geometric optimization results. Additionally, when the dianhydride was ODPA, BPADA or 6FDA, no apparent difference was found in either the transmittance or solubility between two series of polyimides, which could be attributed that twisted and flexible ether linkages, as well as bulky substituents, led to the “already weakened” inter- and intramolecular CT interaction and cohesive force. However, when it came to rigid and stiff dianhydride, e.g., BPDA, PI-3′ took an obvious advantage over PI-3 in transmittance and solubility, which was possibly owed to the larger molecular chain d-spacing imparted by equatorial, axial C–O. An overall investigation of PI-(1′-5′) and PI-(1-5) on aspects of thermal, mechanical, morphological, soluble and optical performance values was carried out, and the conformation effects of HBPA isomers on the properties of two series of polyimides were discussed in detail.
Rheological Model and Transition Velocity Equation of a Polymer Solution in a Partial Pressure Tool
Authors: Huang Bin , Hu Xinyu , Fu Cheng , Liu Chongjiang , Wang Ying , An Xu
Published: May 2019

In order to solve the problem of the low production degree of oil layers caused by an excessively large permeability difference between layers during polymer flooding, we propose partial pressure injection technology using a partial pressure tool. The partial pressure tool controls the injection pressure of a polymer solution through a throttling effect to improve the oil displacement effect in high- and low-permeability reservoirs. In order to analyze the influence of the partial pressure tool on the rheological property of the polymer solution, a physical model of the tool is established, the rheological equation of the polymer solution in the partial pressure tool is established according to force balance analysis, the transition velocity equation for the polymer solution is established based on the concept of stability factor, and the influence of varying the structural parameters of the partial pressure tool on the rheological property of the polymer solution is analyzed. The results show that the pressure drop of the polymer solution increases with the decrease of the front groove angle of the partial pressure tool (from 60° to 30°), reaching a maximum of 1.77 MPa at a front groove angle of 30°. Additionally, the pressure drop of the polymer solution increases with the decrease of the outer cylinder radius (from 25 to 24 mm), reaching a maximum of 1.32 MPa at a radius of 24 mm. However, the apparent viscosity of the polymer solution before and after flowing through the partial pressure tool does not change for any of the studied parameters. These research results are of great significance to research on partial pressure injection technology and enhanced oil recovery.
Crosslinking Effect on Thermal Conductivity of Electrospun Poly(acrylic acid) Nanofibers
Authors: Park Yeongcheol , Lee Suyeong , Ha Sung Soo , Alunda Bernard , Noh Do Young , Lee Yong Joong , Kim Sangwon , Seol Jae Hun
Published: May 2019

The thermal conductivity (k) of poly(acrylic acid) (PAA) nanofibers, which were electrospun at various electrospinning voltages, was measured using suspended microdevices. While the thermal conductivities of the as-spun PAA nanofibers varied depending on the electrospinning voltages, the most pronounced 3.1-fold increase in thermal conductivity in comparison to that of bulk PAA was observed at the electrospinning voltage of 14 kV. On the other hand, a reduction in the thermal conductivity of the nanofibers was observed when the as-spun nanofibers were either thermally annealed at the glass transition temperature of PAA or thermally crosslinked. It is notable that the thermal conductivity of crosslinked PAA nanofibers was comparable to that of crosslinked bulk PAA. Polarized Raman spectroscopy and Fourier transform infrared spectroscopy verified that the k enhancement via electrospinning and the k reduction by the thermal treatments could be attributed to the conformational changes between gauche and trans states, which may be further related to the orientation of molecular chains. In contrast, hydrogen bonds did not contribute significantly to the k enhancement. Additionally, the suppression of k observed for the crosslinked PAA nanofibers might result from the shortening of single molecular chains via crosslinking.