bluuebunny/crossref_metadata_2025_split huggingface dataset:
Generation and Analysis of Axiolitic Liquid‐Metal Droplets in a T‐Junction Microfluidic Device
Authors: Jin Taoming , Hadji Edward Mohamed , Zhao Na , Duan Zhenya , Wang Jingtao 
Published: April 2019

AbstractLiquid metals like the eutectic gallium‐indium (EGaIn) alloys are fantastic materials for producing micro‐droplets. In this work, polyethylene glycol (PEG) and deionized (DI) water were chosen as the continuous phase, and EGaIn is the dispersed phase to generate spherical and non‐spherical (axiolitic) droplets in a T‐junction microfluidic device. Especially for axiolitic droplets, a systematic investigation on the relation of their sizes and flow features was done. A general formula as a function of both the flow rate Qc of the continuous phase and the flow‐rate ratio R(Qc/Qd) is given to fit all the experimental data. Furthermore, effects of the viscosity of the continuous phase on the droplet size, size distribution and hydrodynamic regimes are also discussed. When the viscosity gets higher, the general droplet size gets smaller, the zone for generating axiolitic droplets becomes narrower, and the size distribution of the droplets is relatively worse. These are all because the correlation among the viscosity, the oxide layer on the droplet interface and the droplet morphology. The higher the viscosity is, the thinner the oxide layer is, and the less mechanical stability the droplets would have. The results of axiolitic droplets of liquid metals have wide potential applications in microfluidics, electronics, thermal probe and so on, since the axiolitic droplets are anisotropic compared to the spherical.
Efficient Production of Ethyl Levulinate from Furfuryl Alcohol Catalyzed by Modified Zirconium Phosphate
Authors: Zhai Peng , Lv Guojun , Cai Zhe , Zhu Yongqiang , Li Haichao , Zhang Xubin , Wang Fumin 
Published: April 2019

AbstractThe catalytic activities of various solid acid catalysts were investigated via the reaction of the direct alcoholysis from furfuryl alcohol to ethyl levulinate. The modified zirconium phosphate with sulfuric acid, prepared via a sol‐gel method, exhibited excellent catalytic performance. By controlling the S/Zr mole ratio of 0.5 at the catalyst preparation, the modified zirconium phosphate catalyst obtained catalytic activity of 97.8% EL yield and 100% FA conversion. The mechanism of enhancing catalytic activity of modified zirconium phosphate was investigated. Owing to the higher specific surface area and more Lewis and Brønsted acid sites, the modified zirconium phosphate catalyst displayed higher catalytic activity in comparison to unmodified zirconium phosphate. In addition, the modified zirconium phosphate catalyst was suitable for a broad temperature range. This modification method can provide a new way to enhance Lewis and Brønsted acidity of zirconium phosphate by adjusting S/Zr ratio rather than the P/Zr ratio.
Is all publicity good publicity? The impact of direct and indirect media pressure on the adoption of governance practices
Authors: Shipilov Andrew V. , Greve Henrich R. , Rowley Timothy J. 
Published: April 2019

AbstractResearch SummaryMedia coverage is known to influence firms' behavior, but it is less known whether coverage of firms' partners also has an effect. In a context of governance practices' diffusion in Canada, we distinguish the effect of direct media coverage of the firm's activities, from indirect coverage, defined as media coverage of the firms' interlock partners. We examine whether the coverage is laden with positive or negative emotions. We find that both direct and indirect media coverage have a strong effect on firms' adoption of practices, either when the tone is positive or negative. The findings indicate that media coverage has broader and deeper effects on firms' actions than previously known.Managerial SummaryFirms are under pressure from many outside stakeholders who want them to change. This pressure is felt strongly when it is expressed through mass media attention to the firms or their practices, and often persuades management to make changes. We examine the effect of media coverage on changes in governance practices, finding that media influences reach all the way to the board. In addition, we find that both critique and praise can lead a firm to make changes in its governance practices. The media attention does not even have to be directed to the firm itself: when media targets companies that share common directors with the focal firm, the firm's board usually responds by adopting governance practices as if media targeted the firm.
Bacterially Produced, Nacre‐Inspired Composite Materials
Authors: Spiesz Ewa M. , Schmieden Dominik T. , Grande Antonio M. , Liang Kuang , Schwiedrzik Jakob , Natalio Filipe , Michler Johann , Garcia Santiago J. , Aubin‐Tam Marie‐Eve , Meyer Anne S. 
Published: April 2019

AbstractThe impressive mechanical properties of natural composites, such as nacre, arise from their multiscale hierarchical structures, which span from nano‐ to macroscale and lead to effective energy dissipation. While some synthetic bioinspired materials have achieved the toughness of natural nacre, current production methods are complex and typically involve toxic chemicals, extreme temperatures, and/or high pressures. Here, the exclusive use of bacteria to produce nacre‐inspired layered calcium carbonate‐polyglutamate composite materials that reach and exceed the toughness of natural nacre, while additionally exhibiting high extensibility and maintaining high stiffness, is introduced. The extensive diversity of bacterial metabolic abilities and the possibility of genetic engineering allows for the creation of a library of bacterially produced, cost‐effective, and eco‐friendly composite materials.
Laser‐Assisted Strain Engineering of Thin Elastomer Films to Form Variable Wavy Substrates for Cell Culture
Authors: Tomba Caterina , Petithory Tatiana , Pedron Riccardo , Airoudj Aissam , Di Meglio Ilaria , Roux Aurélien , Luchnikov Valeriy 
Published: April 2019

AbstractEndothelial and epithelial cells usually grow on a curved environment, at the surface of organs, which many techniques have tried to reproduce. Here a simple method is proposed to control curvature of the substrate. Prestrained thin elastomer films are treated by infrared laser irradiation in order to rigidify the surface of the film. Wrinkled morphologies are produced upon stress relaxation for irradiation doses above a critical value. Wrinkle wavelength and depth are controlled by the prestrain, the laser power, and the speed at which the laser scans the film surface. Stretching of elastomer substrates with a “sand clock”‐width profile enables the generation of a stress gradient, which results in patterns of wrinkles with a depth gradient. Thus, different combinations of topography changes on the same substrate can be generated. The wavelength and the depth of the wrinkles, which have the characteristic values within a range of several tens of µm, can be dynamically regulated by the substrate reversible stretching. It is shown that these anisotropic features are efficient substrates to control polarization of cell shapes and orientation of their migration. With this approach a flexible tool is provided for a wide range of applications in cell biophysics studies.
Stimulus‐Responsive Anti‐Oxidizing Drug Crystals and their Ecological Implication
Authors: Kim Byoung Soo , Leong Jiayu , Yu Seung Jung , Cho Younghak , Park Chang Gyun , Kim Da‐Hye , Ko Eunkyung , Im Sung Gap , Lee Jonghwi , Kim Young Jun , Kong Hyunjoon 
Published: April 2019

AbstractVarious antioxidants are being used to neutralize the harmful effects of reactive oxygen species (ROS) overproduced in diseased tissues and contaminated environments. Polymer‐directed crystallization of antioxidants has attracted attention as a way to control drug efficacy through molecular dissolution. However, most recrystallized antioxidants undertake continuous dissolution independent of the ROS level, thus causing side‐effects. This study demonstrates a unique method to assemble antioxidant crystals that modulate their dissolution rate in response to the ROS level. We hypothesized that antioxidants recrystallized using a ROS‐labile polymer would be triggered to dissolve when the ROS level increases. We examined this hypothesis by using catechin as a model antioxidant. Catechin was recrystallized using polyethylenimine cross‐linked with ROS‐labile diselanediylbis‐(ethane‐2,1‐diyl)‐diacrylate. Catechin crystallized with the ROS‐labile polymer displays accelerated dissolution proportional to the H2O2 concentration. The ROS‐responsive catechin crystals protect vascular cells from oxidative insults by activating intracellular glutathione peroxidase expression and, in turn, inhibiting an increase in the intracellular oxidative stress. In addition, ROS‐responsive catechin crystals alleviate changes in the heart rate of Daphnia magna in oxidative media. We propose that the results of this study would be broadly useful for improving the therapeutic efficacy of a broad array of drug compounds.
Aggregation‐Induced Electrochemiluminescence by Metal‐Binding Protein Responsive Hydrogel Scaffolds
Authors: Jiang Hui , Qin Zhaojian , Zheng Youkun , Liu Liu , Wang Xuemei 
Published: April 2019

AbstractFunctionalized hydrogels have aroused general interest due to their versatile applications in biomaterial fields. This work reports a hydrogel network composed of gold nanoclusters linked with bivalent cations such as Ca2+, Mg2+, and Zn2+. The hydrogel exhibits both aggregation‐induced emission (AIE) and aggregation‐induced electrochemiluminescence (AIECL) effects. Most noteworthy, the AIECL effect (≈50‐fold enhancement) is even more significant than the corresponding AIE effect (approximately fivefold enhancement). Calmodulin, a Ca2+ binding protein, may efficiently regulate the AIECL dynamics after specific binding of the Ca2+ linker, with the linear range from 0.3 to 50 µg mL−1 and a limit of detection of 0.1 µg mL−1. Considering the important roles of bivalent cations in the life system, these results may pave a new avenue for the design of a biomolecule‐responsive AIECL‐type hydrogel with multifunctional biomedical purposes.
Ellagic acid ameliorates cisplatin induced hepatotoxicity in colon carcinogenesis
Authors: Goyal Yasmeen , Koul Ashwani , Ranawat Pavitra 
Published: April 2019

AbstractThe clinical application of cisplatin (CP), one of the most extensively used antineoplastic drug, is restricted by its numerous side effects. CP's antitumor potential resides in the free generation of reactive oxygen species leading to oxidative stress. This stress is a source of the side effects associated with its use. Ellagic acid (EA), a polyphenol is known to possess multiple health benefits owing to its antioxidant properties. EA is largely metabolized by the colon microbiota of different mammals and therefore was a polyphenol of choice in the present study. The present study was thus carried out to explore the protective potential of EA on CP induced hepatotoxicity in colon tumor bearing mice. The administration of EA (10 mg/kg bwt po daily for 6 weeks) significantly ameliorated the toxicity caused by CP (5 mg/kg bwt ip once a week for 4 weeks). Activities of liver marker enzymes and lactate dehydrogenase were brought back to normal. EA cotreatment also led to a marked reduction in the extent of peroxidative damage to liver tissue as was evident from the improvement in the histopathological changes observed and FT‐IR analysis. The present study, therefore, suggests that the administration of EA reduces the CP‐induced hepatotoxicity, thereby emerging out as a potential candidate for chemopreventive action.
Human albumin augmented airway inflammation induced by PM2.5 in NC/Nga mice
Authors: Nagaoka Kenjiro , Ogino Keiki , Ogino Noriyoshi , Ito Tatsuo , Takemoto Kei , Ogino Shihona , Seki Yuka , Hamada Hiroki , Fujikura Yoshihisa 
Published: April 2019

AbstractThe synergic allergic inflammatory effects of particulate matter (PM) 2.5 and human albumin were investigated in NC/Nga mice, which are hypersensitive to mite allergens. PM2.5 or PM2.5 plus human albumin with aluminum oxide was injected twice intraperitoneally for sensitization. After 7 days, PM2.5 or PM2.5 plus human albumin was administered five times intranasally to mice for further sensitization. Subsequently, PM2.5 was administered as a challenge on the 11th day. On the 12th day, mice were examined for airway hyperresponsiveness (AHR), bronchoalveolar lavage fluid (BALF) cell count, mRNA expression of Th1, Th2 cytokines, chemokines, and mucus proteins (MUC5AC and MUC5B) in the lung tissue and histopathology. Although PM2.5 or human albumin alone did not induce allergic airway inflammation, simultaneous inoculation of PM2.5 and human albumin‐induced airway inflammation showing increase in AHR, total BALF cell numbers, mRNA levels of IL‐13, eotaxin 1, eotaxin 2, and MUC5AC, and anti‐IG against human serum albumin. Inflammation was observed around the bronchus in PM2.5 plus human albumin‐induced lungs. These results demonstrate that PM2.5 can induce allergic airway inflammation through the synergistic action with human albumin in NC/Nga mice.
T‐2 toxin downregulates LHCGR expression, steroidogenesis, and cAMP level in human cumulus granulosa cells
Authors: Pogrmic‐Majkic Kristina , Samardzija Nenadov Dragana , Stanic Bojana , Milatovic Stevan , Trninic‐Pjevic Aleksandra , Kopitovic Vesna , Andric Nebojsa 
Published: April 2019

AbstractOur goals were to investigate whether environmentally relevant doses of T‐2 toxin can affect human ovarian granulosa cells' function and to reveal the potential mechanism of T‐2 toxin's action. Results showed that T‐2 toxin strongly attenuated luteinizing hormone/choriogonadotropin receptor (LHCGR) mRNA expression in follicle‐stimulating hormone (FSH)‐stimulated human cumulus granulosa cells. Addition of human chorionic gonadotropin was not able to elicit maximal response of ovulatory genes amphiregulin, epiregulin, and progesterone receptor. T‐2 toxin reduced mRNA levels of CYP19A1 and steroidogenic acute regulatory protein (STAR) and lowered FSH‐stimulated estradiol and progesterone production. Mechanistic experiments demonstrated that T‐2 toxin decreased FSH‐stimulated cyclic adenosine monophosphate (cAMP) production. Addition of total PDE inhibitor 3‐isobutyl‐1‐methylxanthine prevented T‐2 toxin's action on LHCGR, STAR, and CYP19A1 mRNA expression in FSH‐stimulated human cumulus granulosa cells. Furthermore, T‐2 toxin partially decreased 8‐bromoadenosine 3′5′‐cyclic monophosphate (8‐Br‐cAMP)‐stimulated LHCGR and STAR, but did not affect 8‐Br‐cAMP‐stimulated CYP19A1 mRNA expression in human cumulus granulosa cells. Overall, our data indicate that environmentally relevant dose of T‐2 toxin decreases steroidogenesis and ovulatory potency in human cumulus granulosa cells probably through activation of PDE, thus posing a significant risk for female fertility.
CRISPR/Cas9‐RNA interference system for combinatorial metabolic engineering of Saccharomyces cerevisiae
Authors: Kildegaard Kanchana Rueksomtawin , Tramontin Larissa Ribeiro Ramos , Chekina Ksenia , Li Mingji , Goedecke Tobias Justus , Kristensen Mette , Borodina Irina 
Published: April 2019

AbstractThe yeast Saccharomyces cerevisiae is widely used in industrial biotechnology for the production of fuels, chemicals, food ingredients, food and beverages, and pharmaceuticals. To obtain high‐performing strains for such bioprocesses, it is often necessary to test tens or even hundreds of metabolic engineering targets, preferably in combinations, to account for synergistic and antagonistic effects. Here, we present a method that allows simultaneous perturbation of multiple selected genetic targets by combining the advantage of CRISPR/Cas9, in vivo recombination, USER assembly and RNA interference. CRISPR/Cas9 introduces a double‐strand break in a specific genomic region, where multiexpression constructs combined with the knockdown constructs are simultaneously integrated by homologous recombination.We show the applicability of the method by improving cis,cis‐muconic acid production in S. cerevisiae through simultaneous manipulation of several metabolic engineering targets.The method can accelerate metabolic engineering efforts for the construction of future cell factories.
A nAttractor mechanism for nAdS2/nCFT1 holography
Authors: Larsen Finn 
Published: April 2019

AbstractWe study the nearly AdS2geometry of nearly extremal black holes in$$ \mathcal{N}=2 $$N=2supergravity in four dimensions. In the strictly extreme limit the attractor mechanism for asymptotically flat black holes states that the horizon geometries of these black holes are independent of scalar moduli. We determine the dependence of the near extreme geometry on asymptotic moduli and express the result in simple formulae that generalize the extremal attractor mechanism to nearly extreme black holes. This is a nAttractor mechanism.
Evaluation of a Novel Bony Landmark‐Based Method for Teaching Percutaneous Insertion of Subclavian Venous Catheters in Pediatric Patients
Authors: Lin Zhiyang Jace , Lee York Tien , Chua Joyce Horng Yiing , Wang Rachel , Lee Vanessa , Cheah Sue Mei , Saffari Seyed Ehsan , Lam Joyce Ching Mei , Loh Amos Hong Pheng 
Published: April 2019

AbstractBackgroundSurgical trainees performing subclavian vein (SCV) cannulation often incorrectly perceive needle trajectory and anatomical relations. As surface landmark‐based methods derived from adult surgical practice may be less effective in younger patients, we developed and evaluated a novel bony landmark‐based method for teaching SCV cannulation for central venous access device (CVAD) placement in children.MethodsOver 2 sequential 3‐year periods, pediatric surgical trainees were taught infraclavicular SCV cannulation via surface‐ and bony‐landmark approaches, respectively. We prospectively recorded patient, surgeon and operative details on all Hickman line and port‐a‐cath insertions placed by trainees as the first surgeon via percutaneous infraclavicular SCV puncture and compared procedural outcomes and complications across both periods.ResultsOf 271 cases included in the study, trainees performed 52 (50.5%) and 92 (54.8%) procedures in the first and second periods, respectively. Patients in both periods did not differ by gender, disease, CVAD device, or prior CVAD, chemotherapy or infection status. In the second (bony landmark) period, although patients were younger (6.0 vs. 8.7 years, P = 0.003) mean procedural duration was shorter (42.5 vs. 58.3 min, P < 0.001). Also, cannulation attempts and complication rates did not differ significantly between study periods (P = 0.257 and 1.0, respectively).ConclusionsWith the bony landmark approach, trainees could perform the procedures faster despite operating on younger patients, without impacting complication rates and cannulation attempts. Bony landmarks may better approximate SCV position across a range of ages, thus improving the consistency of SCV cannulation in CVAD placements in children.
The Influence of Clays on Human Health: A Medical Geology Perspective
Authors: Finkelman Robert B. 
Published: April 2019

AbstractClay is unique especially from the perspective of medical geology, that is, the impacts of geologic materials and geologic processes on animal and human health. Clay is the only natural material that can impact human health through all routes of exposure: ingestion, inhalation, and dermal contact. Moreover, these impacts can be harmful as well as beneficial. Ingestion of clay, a form of geophagy, has been practiced for millennia and is still widely practiced today. Humanoids have been ingesting clay for at least two million years to ease indigestion and counteract poisons. Some additional benefits may accrue from eating clays such as providing some nutrients but these benefits are far outweighed by the likely negative consequences such as tissue abrasion, intestinal blockage, anemia, exposure to pathogens and toxic trace elements, and potassium overdose. Inhalation of airborne minerals including clays has impacted the heath of millions. In the 1930s thousands of people living in the Dust Bowl in the U.S. southwest inhaled copious amounts of clay contributing to deadly ‘dust pneumonia.’ Using clay as a poultice to stem bleeding and cure certain skin ailments is an age-old practice that still has many adherents. A classic recent example of the antibacterial properties of clay is the use of certain clays to cure Buruli ulcer, a flesh eating disease. However, walking barefoot on clays in certain volcanic soils can result in non-filarial podoconiosis or elephantiasis. The absence of clays in soils can have serious health consequences. In South Africa, clay-poor soils yield crops lacking in essential nutrients and may be the principal cause of Msileni joint disease. Clearly, a detailed knowledge of the clays in the environment can have significant benefits to human health and wellbeing.
Clay Minerals in Skin Drug Delivery
Authors: Viseras César , Carazo Esperanza , Borrego-Sánchez Ana , García-Villén Fátima , Sánchez-Espejo Rita , Cerezo Pilar , Aguzzi Carola 
Published: April 2019

AbstractClays have played an important role in medicine since the dawn of mankind and are still applied widely as active ingredients and/or excipients in pharmaceutical formulations. Due to their outstanding properties of large retention capacity, swelling and rheological properties, and relative low cost, they have been used widely as advanced carriers for the efficient delivery of drugs by modifying their release (rate and/or time), increasing the stability of the drug, improving the dissolution profile of a drug, or enhancing their intestinal permeability. In addition, recent studies have shed new light on the potential of clay minerals in the nanomedicine field due to their biocompatibility, beneficial effects of clay nanoparticles on cellular adhesion, proliferation, and differentiation. Use as active ingredients and excipients are exerted via the oral and topical administration pathways. Skin drug delivery represents an attractive alternative to the oral route, providing local and/or systemic drug delivery. Due to their complex structures, however, most drugs penetrate the human skin only with difficulty. Enormous efforts have been invested, therefore, in developing advanced drug delivery systems able to overcome the skin barrier. Most strategies require the use of singular materials with new properties. In particular, and on the basis of their inherent properties, clay minerals are ideal candidates for the development of intelligent skin drug delivery systems. In this article, the properties of clay materials and their use in the skin-addressed pharmaceutical field are reviewed. A brief introduction of skin physiology and biopharmaceutical features of penetration by a drug through the skin layers is also included and is designed to shed light on the optimum properties of ideal nanosystems for advanced skin drug delivery. Special attention is devoted to the pharmacological functions of clays and their biomedical applications in pelotherapy, wound healing, regenerative medicine, antimicrobial, and dermocosmetics.