bluuebunny/crossref_metadata_2025 huggingface dataset:
Validating additive correction schemes against gradient‐based extrapolations
Authors: Kraus Peter , Frank Irmgard
Published: April 2019

The use of additive correction schemes to obtain structures and vibrational frequencies of increasingly larger molecules is becoming more common. Such approaches, based on the cubic extrapolation formula applied directly to the quantity of interest, have been successfully validated only at the highest levels of computational accuracy: for coupled cluster methods with comparably large basis sets. Here, a systematic validation of geometries and vibrational frequencies is carried out, including more affordable and relevant levels of theory, such as the Møller‐Plesset perturbation theory applied with smaller basis sets. Comparisons of such additive schemes against the more rigorous gradient‐based extrapolation are presented. The cbs() routine of the open‐source quantum‐chemistry package Psi4 has been extended for this purpose. The results confirm that geometries and frequencies of covalently bound species obtained with additive correction schemes are in an excellent agreement with the results of gradient‐based extrapolations. However, when applied to systems involving noncovalent interactions, the errors due to such schemes are significantly larger. In general, we propose the application of gradient‐based extrapolations, as they incur no extra cost compared to additive schemes.
A specified‐time control framework for control‐affine systems and rigid bodies: A time‐rescaling approach
Authors: Peng Xiuhui , Sun Junyong , Geng Zhiyong
Published: April 2019

This paper addresses the specified‐time control problem for control‐affine systems and rigid bodies, wherein the specified‐time duration can be designed in advance according to the task requirements. By using the time‐rescaling approach, a novel framework to solve the specified‐time control problem is proposed, and the original systems are converted to the transformation systems based on which the specified‐time control laws for both control‐affine systems and rigid bodies are studied. Compared with the existing approaches, our proposed specified‐time control laws can be derived from the known stabilization control laws. To our best knowledge, it is the first time that transformation system–based specified‐time control framework for control‐affine system and rigid body dynamics is proposed. To further improve the convergence performance of specified‐time control, a finite‐time attitude synchronization control law for rigid bodies on rotation matrices is proposed, and thereby, the finite‐time–based specified‐time control law is designed eventually. In the end, numerical simulations and SimMechanics experiments are provided to illustrate effectiveness of the theoretical results.
Simultaneous fault detection and antisaturated control based on dynamic observer for inverted pendulum control system
Authors: Pang Guochen , Cao Jinde , Chen Xiangyong , Qiu Jianlong
Published: April 2019

This paper focuses on the problem of simultaneous fault detection and antisaturated control for an inverted pendulum control system. The system input is the acting control voltage that generates the force on the cart. However, the acting control voltage is obviously limited by the voltage amplitude. This means that the actuator of the constructed system model is saturated. Hence, the detector/controller unit produces two signals: the detection and antisaturated control. In this process, the effects of disturbances and noises on detection and control purposes need to be suppressed. Finally, two simulation examples verify the effectiveness of the method.
Momentum dispersion and mass resolution of magnetic sector instruments for surface analysis
Authors: Oechsner Hans
Published: April 2019

The momentum‐dependent dispersion of ion trajectories in a homogeneous magnetic sector field is derived by a trigonometric method. Contrary to the often used transfer matrix technique, the results are not restricted to small momentum differences. Based on the results of the trigonometric evaluation, an expression for the mass resolution of a magnetic sector for an entering ion beam is derived and extensively discussed. An example for high‐resolution magnetic mass spectrometry is presented.
Three‐Dimensional Ordered Structures of Metal‐Organic Frameworks for Carbon Tetrachloride Sensing and Comparative Study
Authors: Luo Wenyang , Zheng Yue , Yan Jun , Chen Yunlin
Published: April 2019

Three‐dimensional (3D) ordered structure of PS@ZIF‐8 and FT‐ZIF‐8 was prepared by self‐assembly method. The 3D ordered structure of PS@ZIF‐8 and FT‐ZIF‐8 were used to investigate the sensing characteristics for carbon tetrachloride in real time, and the two structures exhibited good response to carbon tetrachloride. It was found that the response time required to reach the maximum reflection peak only 2 s for FT‐ZIF‐8, and the shift of the reflection peak from about 825 nm to 836 nm of about 31 nm for PS@ZIF‐8. The relationship of the shift peak position with different concentration of carbon tetrachloride was demonstrated to be linear. Moreover, The fabricated 3D ordered structures exhibited high long‐term, repeatability and stability, which are beneficial for practical applications.
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

Liquid 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

The 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

Research Summary

Media 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 Summary

Firms 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

The 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

Endothelial 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

Various 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

Functionalized 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.
Evaluation of the shear transfer mechanisms in reinforced concrete beams using photogrammetry
Authors: Valença Jónatas , Carmo Ricardo N. F.
Published: April 2019

The models to predict the shear behavior in reinforced concrete (RC) members are still far from be consensual. Thus, a detailed understanding of the physical phenomenon and a detailed monitoring of shear tests on RC members is fundamental. Identify and quantify separately the contribution of each component of the shear transfer mechanism it is a challenge. The traditional instrumentation usually results in the evaluation of a limited number of sections. Additionally, technologies based on image analysis have been applied to structural monitoring with excellent results. In this paper, the method Photo‐Shear, developed to monitoring shear tests based on photogrammetry, is presented. The method allows a better understanding of the shear strength mechanism by acquiring data from the surface of RC members. Then, postprocessing procedures leads to outputs with the redundancy and complementarity necessary to characterize: (a) displacement and strain fields; (b) overall shear deformation (distortion and rotation); (c) load path and direction of the compression strut; (d) shear cracks' characterization; and (e) the aggregate interlock effect. The method was validated by monitoring two RC beams tests. Based on the results obtained, several advantages of the proposed Photo‐Shear method were demonstrated over the traditional instrumentation, namely, the quantity and quality of the information obtained, and the redundancy and complementarity of the results analyzed.
Emergence of Function in Synthetic Chemical Networks
Authors: Ashkenasy Gonen
Published: April 2019

Gonen Ashkenasy
is a Professor of Chemistry and Head of the Laboratory for Systems Chemistry at the Ben‐Gurion University of the Negev (Israel). He is a current member of the ChemSystemsChem Editorial Board.
Ellagic acid ameliorates cisplatin induced hepatotoxicity in colon carcinogenesis
Authors: Goyal Yasmeen , Koul Ashwani , Ranawat Pavitra
Published: April 2019

The 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

The 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

Our 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.
Annotation and Agency: Teaching Close Reading in the Primary Grades
Authors: Ensley Alice , Rodriguez Sanjuana C.
Published: April 2019

Close reading is a strategy that can help young students read complex texts. The authors share a process for teaching close reading that can be implemented in primary classrooms.
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

The 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.
Probing anomalous driving
Authors: Haack Michael , Sarkar Debajyoti , Yarom Amos
Published: April 2019

Abstract

We study the effects of driving a magnetically charged black brane solution of Einstein-Maxwell-Chern-Simons theory by a time dependent electric field. From a holographic perspective, we find that placing a sample in a background magnetic field and driving the system via a parallel electric field generates a charge current which may oscillate for long periods and (or) may exhibit non-Ohmic behavior. We discuss how these two effects manifest themselves in various types of quenches and in periodic driving of the sample.
Novel astrophysical probes of light millicharged fermions through Schwinger pair production
Authors: Korwar Mrunal , Thalapillil Arun M.
Published: April 2019

Abstract

The extreme properties of neutron stars provide unique opportunities to put constraints on new particles and interactions. In this paper, we point out a few interesting ideas that place constraints on light millicharged fermions, with masses below around an eV, from neutron star astrophysics. The model-independent bounds are obtained leveraging the fact that light millicharged fermions may be pair produced copiously via non-perturbative processes in the extreme electromagnetic environments of a neutron star, like a Magnetar. The limits are derived based on the requirement that conventional Magnetar physics not be catastrophically affected by this non-perturbative production. It will be seen that Magnetar energetics, magnetic field evolution and spin-down rates may all be influenced to various degrees by the presence of the millicharged particles.
A nAttractor mechanism for nAdS2/nCFT1 holography
Authors: Larsen Finn
Published: April 2019

Abstract

We 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

Background

Surgical 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.

Methods

Over 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.

Results

Of 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).

Conclusions

With 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

Clay 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

Clays 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.
Clay-Based Biohybrid Materials for Biomedical and Pharmaceutical Applications
Authors: Ruiz-Hitzky Eduardo , Darder Margarita , Wicklein Bernd , Castro-Smirnov Fidel Antonio , Aranda Pilar
Published: April 2019

Clays have traditionally been linked to health care, being used for centuries in the fight against infections and diseases. Similarly, biohybrids produced by combinations of clays and biological species through ‘bottom-up’ approaches have been evaluated over the past decade for biomedical and pharmaceutical uses. These biohybrids show interesting features such as biocompatibility and biodegradability which make them suitable for healthcare applications. The aim of the present communication was to review recent research contributions describing progress and the role of biohybrid materials based on clays in biomedicine and pharmacy disciplines. Emphasis will be on the authors’ own experience of this topic, particularly on aspects related to controlled drug-delivery systems, adjuvants of vaccines, and vectors for non-viral gene transfection. Bionanocomposites offer several advantages for use in the design of new and efficient pharmacological formulations for cutaneous and oral administration. In these systems, the drug is typically entrapped in the clay and protected by a biopolymer matrix, and both components contribute to a gradual release of the drug. Clay-based hybrids have also shown their efficacy in vaccines as they can act as nanocarriers of viral particles, due to the biomimetic interface created on the clay surface after adsorption of suitable biomolecules such as phospholipids, while the clay acts as an adjuvant to increase the efficacy of the vaccine. Finally, a new application of clays as non-viral vectors for controlled gene delivery is attracting increasing interest in the treatment of diverse diseases; clays such as sepiolite have demonstrated their ability to act as nanocarriers of nucleic acids and facilitate their transfection in mammalian cells.
NovaSil Clay for the Protection of Humans and Animals from Aflatoxins and Other Contaminants
Authors: Phillips Timothy D. , Wang Meichen , Elmore Sarah E. , Hearon Sara , Wang Jia-Sheng
Published: April 2019

Aflatoxin contamination of diets results in disease and death in humans and animals. The objective of the present paper was to review the development of innovative enterosorption strategies for the detoxification of aflatoxins. NovaSil clay (NS) has been shown to decrease exposures to aflatoxins and prevent aflatoxicosis in a variety of animals when included in their diets. Results have shown that NS clay binds aflatoxins with high affinity and high capacity in the gastrointestinal tract, resulting in a notable reduction in the bioavailability of these toxins without interfering with the utilization of vitamins and other micronutrients. This strategy is already being utilized as a potential remedy for acute aflatoxicosis in animals and as a sustainable intervention via diet. Animal and human studies have confirmed the apparent safety of NS and refined NS clay (with uniform particle size). Studies in Ghanaians at high risk of aflatoxicosis have indicated that NS (at a dose level of 0.25% w/w) is effective at decreasing biomarkers of aflatoxin exposure and does not interfere with levels of serum vitamins A and E, iron, or zinc. A new spinoff of this strategy is the development and use of broad-acting sorbents for the mitigation of environmental chemicals and microbes during natural disasters and emergencies. In summary, enterosorption strategies/therapies based on NS clay are promising for the management of aflatoxins and as sustainable public health interventions. The NS clay remedy is novel, inexpensive, and easily disseminated.
Isoderivative chromosome 17 with multiple copies of RARα–PML fusions and Tp53 deletion in a rare case of APML
Authors: Shetty Dhanlaxmi , Talker Elizabeth , Sengar Manju , Subramanian Papagudi G.
Published: April 2019

Acute Promyelocytic Leukemia (APML) is a malignancy of cells in myeloid lineage. It is a neoplasm described by proliferation and accumulation of immature neutrophils called promyelocytes in the bone marrow, inhibiting normal cell production, which results in lower numbers of blood cells circulating the body. A minor but significant proportion of patients with APML harbor complex and cryptic rearrangements. Presence of isoderivative 17 with t(15;17) is very rare. We report a case of adult APML with amplification of RARα/PML fusion protein, a consequence of isoderivative 17 with duplication of normal chromosome 15 and 17 and Tp53 deletion on derivative 17. Immunophenotyping by flow cytometry, presence of pancytopenia and epistaxis helped classify the patient as APML. FISH was used for confirmation of the same and indicated involvement of additional abnormalities.
Splenectomy following JAK1/JAK2 inhibitor therapy in patients with myelofibrosis undergoing allogeneic stem cell transplantation
Authors: Barabanshikova Maria Vladimirovna , Zubarovsky Igor Nikolaevich , Savrasov Vjacheslav Mikhailovich , Korolkov Andrey Jurjevich , Baykov Vadim Valentinovich , Botina Anna Vjacheslavovna , Vlasova Julia Jurjevna , Moiseev Ivan Sergeevich , Darskaya Elena Igorevna , Morozova Elena Vladislavovna , Afanasyev Boris Vladimirovich
Published: April 2019

Background:

Allogeneic hematopoietic stem cell transplantation (alloHSCT) is the only treatment option with curative potential in patients with myelofibrosis (MF). The aim of our study was to evaluate the safety of splenectomy before alloHSCT in MF patients who failed to achieve significant spleen response after ruxolitinib therapy.

Methods:

Splenectomy was performed in 12 patients for alloHSCT with myelofibrosis-primary (6 patients), post-polycythemia vera (3 patients). or postessential thrombocythemia (3 patients) between 2016 and 2018. The patients were prospectively included in the study if persistence of splenomegaly ≥ 25 cm was documented after at least 3 months of ruxolitinib therapy. In eight patients subsequent alloHSCT was performed.

Results:

Median length of hospital stay was 11 (8-30) days, median follow-up after splenectomy was 20.0 (0.6-31.1) months. No deaths were documented, perioperative morbidity was 50%. Three patients experienced portal vein thrombosis and one experienced splenic vein thrombosis. One patient developed pancreonecrosis and subdiaphragmatic abscess. Mean leukocyte count was significantly higher 1 month after splenectomy than before, 10.7 ± 1.7 versus 6.9 ± 2.3 × 109/L (p = 0.03). Platelets rate significantly elevated starting Day + 7 after splenectomy (p = 0.01). Median time between splenectomy and alloHSCT was 2.6 (0.17-4.5) months. All patients achieved engraftment. In early posttransplant period no cases of severe sepsis, intraabdominal infections were documented. One patient died after alloHSCT due to thrombotic microangiopathy. Seven patients are alive in disease complete remission. No relapses after alloHSCT were observed. Two-year overall survival in the whole group is 90% (95%CI 98-43%).

Conclusion:

Splenectomy before alloHSCT might be a promising option in patients who failed to achieve significant spleen response after ruxolitinib therapy.
Intraocular involvement of Mantle cell lymphoma
Authors: Iqbal Madiha , Castano Yennifer Gil , Sher Taimur , Kharfan-Dabaja Mohamed A.
Published: April 2019

Lymphomatous involvement of the ocular adnexal region (OAR) is generally rare; however, it constitutes the most common ocular malignancy. Most cases of ocular adnexal lymphomas are extra nodal marginal zone B cell lymphomas. Mantle cell lymphoma involvement (MCL) of the OAR is a less common presentation compared with other lymphomas and it has been reported anecdotally. Studies have suggested an association of OAR involvement with poor prognosis. Here, we report the case of a 61 year old man who started experiencing conjunctival erythema which was followed by development of bilateral proptosis. The diagnosis of Stage IV Mantle cell lymphoma with OAR involvement was confirmed 5 months after patient onset of symptomatology. He underwent treatment with systemic chemotherapy, which was followed by high-dose chemotherapy and autologous hematopoietic cell transplant. He is currently day +100 from his transplant and is in complete remission. A review of the literature regarding ocular involvement of MCL is also summarized.
Mathematical analysis of bio-convective micropolar nanofluid
Authors: Nadeem Sohail , Khan Muhammad Naveed , Muhammad Noor , Ahmad Shafiq
Published: April 2019

The present investigation concentrates on three dimensional unsteady forced bio-convection flow of a viscous fluid. An incompressible flow of a micropolar nanofluid encloses micro-organisms past an exponentially stretching sheet with magnetic field is analyzed. By employing convenient transformation the partial differential equations are converted into the ordinary differential equations which are non-linear. By using shooting method to solved these equations numerically. The influence of the determining parameters on the velocity, temperature, micro-rotation, nanoparticle volume fraction, microorganism are incorporated. The skin friction, heat transfer rate, and the microorganism rate are analyzed. The results depicts that the value of the wall shear stress and Nusselt number are declined while an enhancement take place in the microorganism number. The slip parameters increases the velocity, thermal energy, and microorganism number consequentially. The present investigation are important in improving achievement of microbial fuel cells.
Synchronous Urethral Repair During Prosthetic Surgery: Safety of Planned and Damage Control Approaches Using Suprapubic Tube Urinary Diversion
Authors: Yi Yooni A. , Fuchs Joceline S. , Davenport Michael T. , McKibben Maxim J. , Bergeson Rachel L. , Morey Allen F.
Published: April 2019

Background

Urethral injury during inflatable penile prosthesis (IPP) or artificial urinary sphincter (AUS) placement is rare, and traditionally most prosthetic surgeons abort prosthetic implantation when urethral repair is necessary.

Aim

To report our experience with synchronous urethroplasty (SU) as a planned or damage control surgery during urologic prosthetic surgery, to evaluate the safety and outcomes of the procedure.

Methods

A retrospective review of our IPP and AUS database was completed to identify patients who underwent an SU between 2007 and 2018. We included patients who underwent an SU during prosthetic surgery in either a planned procedure for known stricture or diverticulum or a “damage control” procedure after intraoperative injury.

Outcome

Patient characteristics and surgical outcomes were assessed, with success defined as the absence of urethral stricture and revision surgery.

Results

From our database of 1,508 prosthetic cases, we identified 7 patients (0.46%) who had an SU in the same setting as complete prosthesis placement (4 AUS and 3 IPP [1 combined IPP/AUS], and 1 sling). Three patients underwent planned repair of a known urethral abnormality (urethral diverticulum, urethrocutaneous fistula, and urethral stricture), and 4 underwent repair of an intraoperative urethral injury. Among the patients who experienced an intraoperative urethral injury, contributing etiologies included previous anti-incontinence surgery with periurethral fibrosis (n = 2), severe corporal fibrosis from priapism, and previous urethral disruption from pelvic fracture. Nearly all of the urethroplasties (6 of 7; 86%) were completed with a primary closure. The average indwelling duration of suprapubic tube (SPT) catheters was 4.1 weeks (range, 7 to 47 days). The average duration of follow-up was 21.5 months, and all patients were continent at follow-up. No device infections or urethral complications were identified.

Clinical Implications

Our study illustrates the safety of concomitant urethral repair at time of prosthetic placement as an option to avoid the use of 2 anesthetics and prevent further scarring in high-risk patients.

Strengths & Limitations

This is the first study to address definitive urethral reconstruction during anti-incontinence procedures along with planned concomitant urethroplasty during IPP placement. This promising initial experience is relevant for surgeons who may encounter concomitant urethral pathology in the setting of complex reoperative prosthetic cases. The need for SU is rare, and thus our cohort size was limited in this retrospective, single-institution experience.

Conclusion

SU with prolonged SPT urinary diversion offers a safe damage control approach for men with concomitant urethral pathology during prosthetic surgery without conferring an increased risk of infection or stricture.
State of the environment reporting: an Antarctic case study
Authors: Belbin Lee , Gibson John A.E. , Davis Colin , Watts David , McIvor Ewan
Published: April 2019

The requirement for an Antarctic component to the 2001 Australian State of the environment report initiated the development of a state of the environment system designed to remain current, yet minimize the resources required for maintenance. A series of environmental indicators was developed and refined by a group of experts during a period of 18 months. A simple descriptive template and data for each indicator were incorporated into a web-accessible database system called SIMR (System for Indicator Management and Reporting). The system captures indicator data either dynamically from sensors or by web input by indicator custodians. The system also prompts custodians for regular input of evaluations of indicator status. The system (http://www-aadc.aad.gov.au/soe) has been an effective framework for considering all aspects of state of the environment reporting and a practical tool in research and operational aspects of the Australian Antarctic Division.
Hafgerdingar: a mystery from the King's Mirror explained
Authors: Lehn Waldemar H. , Schroeder Irmgard I.
Published: April 2019

The medieval King's Mirror describes Iceland and Greenland with a scientific accuracy that is remarkable. One of the very few exceptions is the hafgerdingar in the Greenland Sea. The term translates as ‘sea hedges,’ within which a mariner may become trapped at great peril. Many have believed that a real event was being described, although none of the proposed explanations has been totally satisfactory. The most common view currently is based on Steenstrup (1871), who explained the phenomenon as a tidal wave following a submarine earthquake. A simpler and more consistent theory is developed here: that the hafgerdingar are an optical phenomenon, specifically, a superior mirage. Such mirages, quite common in the polar regions, can produce an appearance fully consistent with the original description, as illustrated by several photographs and a computer simulation. Even the peril to seafarers has been corroborated, in the sense that such a mirage is frequently followed by a storm.