bluuebunny/crossref_metadata_2025 huggingface dataset:
In Situ Separation of Chemical Reaction Systems Based on a Special Wettable PTFE Membrane
Authors: Xu Zhe , Wang Li , Yu Cunming , Li Kan , Tian Ye , Jiang Lei
Published: December 2017

Oil–water separation is a worldwide subject because of the increasing demands in numerous applications, involving separation of immiscible products from chemical reaction systems in synthetic industry. Owing to the limitations of low efficiency, high energy consumption, and multiple operations in conventional methods, membranes with special wettability have been widely developed in recent years to effectively separate various oil–water systems. However, few works on treating chemical reaction systems have been reported because of the lack of stability of current membranes in harsh environments, especially during long‐term work. Herein, a continuous in situ separation of chemical reaction systems based on a special wettable porous polytetrafluoroethylene membrane is successfully conducted. The membrane possesses (1) an intrinsic (with no modification) special wettability of highly hydrophobic/oleophilic in air and superoleophilic under water and 2) an excellent long‐term durability in acidic, alkaline, saline, organic, or heating environments. The in situ separation process exhibits both large separation flux (>3500 L m−2 h−1) and high product purity (>99.00%) by continuously filtering synthetic products without interrupting chemical reactions, which is of great significance in industrial fields.
Bipolar Conducting Polymer Crawlers Based on Triple Symmetry Breaking
Authors: Gupta Bhavana , Goudeau Bertrand , Garrigue Patrick , Kuhn Alexander
Published: December 2017

Bipolar electrochemistry can be used in different ways to induce motion of an object, for example by generating gas bubbles in an asymmetric way or by a wireless self‐regeneration mechanism due to the intrinsic symmetry breaking of this concept. Here a complementary approach is explored on the basis of conducting polymer objects addressed in solution by an electric field. The presence of the latter results in a differential polarization of the polymer, thus enabling its oxidation at one extremity and its reduction at the opposite side. This triggers different degrees of swelling and shrinking, leading to important deformations of the object. Combined with an additional asymmetry in the polymer surface morphology, a periodic switching of the electric field orientation allows exploiting these deformations to induce directed crawling motion. This first example of a wireless biomimetic crawler based on conducting polymers opens interesting long‐term perspectives in several areas such as for example wireless valves, pumps and (micro)robotics.
Bottom‐up Nanoencapsulation from Single Cells to Tunable and Scalable Cellular Spheroids for Hair Follicle Regeneration
Authors: Wang Jin , Miao Yong , Huang Yong , Lin Bojie , Liu Xiaomin , Xiao Shune , Du Lijuan , Hu Zhiqi , Xing Malcolm
Published: December 2017

Cell surface engineering technology advances cell therapeutics and tissue engineering by accurate micro/nanoscale control in cell–biomaterial ensembles and cell spheroids formation. By tailoring cell surface, microgels can encapsulate cells for versatile uses. However, microgels are coated in a thick layer to house multiple cells together but not a single cell based. Besides, excessive deposition on cell surface is detrimental to cellular functions. Herein, layer‐by‐layer (LbL) self‐assembly to encapsulate single cell using nanogel is reported, owing to its security and tunable thickness at nanoscale, and further forms cell spheroids by physical cross‐linking on nanogel‐coated cells for delivery. A hair follicle (HF) regeneration model where the dermal papilla cells (DPCs) are given a 3D installation to maintain its ability of HF induction during in vitro culture is studied. Dermal papilla (DP) spheroids are optimized and that LbL‐DPCs aggregation is akin to primary DP is demonstrated. The markers ALP, Versican, and NCAM are examined to investigate that high‐passaged (P8) DP spheroids can restore the hair induction potential, which are lost in 2D culture. New HFs are regenerated successfully by implantation of DP spheroids in vivo.
Tiling of Solar Cell Surfaces: Influence on Photon Management and Microstructure
Authors: Tamang Asman , Sai Hitoshi , Jovanov Vladislav , Matsubara Koji , Knipp Dietmar
Published: December 2017

Microcrystalline silicon thin‐film solar cells prepared on hexagonal tiled surfaces exhibit record short‐circuit current densities and energy conversion efficiencies. However, it remains unclear if hexagonal textured substrates represent the best possible substrate tiling. In this study, hexagonal tiled substrates are compared with square and triangular tiled substrates in terms of photon management and microstructure. The 3D interface morphology of the individual layers of the solar cells is calculated and used as input parameters for the prediction of microcracks in the film and the simulation of 3D optical wave propagation. A comparison of the calculated interface morphologies with experimental results exhibits a good agreement for solar cells on hexagonal textured substrates, permitting calculations for solar cells on square and triangular textured substrates. The investigation of the crack formation process indicates that the square and the triangular textured substrates are superior to the hexagonal textured substrates. Finally, crack‐free triangular textured solar cells exhibit increased short‐circuit current densities compared to hexagonal and square textured solar cells.
X‐ray Radiography to Visualize the Rebar–Cementitious Matrix Interface and Judge the Delay in Corrosion through Self‐Repair by Encapsulated Polyurethane
Authors: Van Tittelboom Kim , Van Belleghem Bjorn , Boone Matthieu N. , Van Hoorebeke Luc , De Belie Nele
Published: December 2017

Corrosion of steel reinforcement is one of the most detrimental attack mechanisms for reinforced concrete structures. The presence of cracks, which are inextricably linked to reinforced concrete, accelerates this attack mechanism. The aim of this study is to heal cracks by an autonomous mechanism, which is triggered upon crack appearance. With an accelerated corrosion test on mortar samples with embedded reinforcement bars, it is shown that the presence of cracks indeed accelerates the onset and propagation of corrosion at the interface between the rebar and the cementitious matrix. Moreover, it is shown that crack healing in both the traditional, manual way and the proposed autonomous way, with an encapsulated one‐component polyurethane, delays the onset and propagation of corrosion. The difference in corrosion behavior is proven by visual evaluation of the rebar surface and by X‐ray radiographic analysis, which is proposed as a successful technique to evaluate the crack healing efficiency and more specifically the potential to delay corrosion.
Liquid Shaping Based on Liquid Pancakes
Authors: Li Xiaoguang , Shi Haixiao , Wang Yiqi , Wang Renxian , Huang Shuai , Huang Junchao , Geng Xingguo , Zang Duyang
Published: December 2017

Liquid marbles with quasi‐spherical shapes have great application potential as miniature containers. Recently, their shape modification is investigated, revealing great possibilities in broadening the uses for such containers. Current methods have demonstrated shape designability, but fine control of the final shape, important in applications, has remained a problem. Here, a facile method, based on a gravity‐induced liquid pancake coated with a nanoparticle monolayer, is proposed that allows continuous segmentation of the liquid. As a result, well‐shaped liquids, as structured liquid marbles with accurate target profiles, are formed. The density of interfacial particles is found to determine the segmentation feasibility and to affect the shaped liquid profile. Additionally, the maximum bifurcation is positively related to the initial particle density. This work basically achieves fine control of the liquid shape, enhancing the foundation for the development of liquid‐based smart containers.
Functional and Switchable Amphiphilic PMMA Surface Prepared by 3D Selective Modification
Authors: Guselnikova Olga , Postnikov Pavel , Sajdl Petr , Elashnikov Roman , Švorčík Vaclav , Lyutakov Oleksiy
Published: December 2017

The design and creation of switchable amphiphilicity on the surface of thin poly(methylmethacrylate) (PMMA) films are described. Amphiphilic properties are achieved through the 3D surface spatially selective modification using the membrane‐assisted diazonium approach. Proposed technique allows simple grafting with the hydrophilic and hydrophobic compounds in the surface valleys or tops, depending on the order of modification steps. Thermally controllable hydro‐ and oleophilicity are achieved by the in‐plane and height distinguished grafting of PMMA films with bis(trifluoromethyl)phenyl and poly(N‐isopropylacrylamide) chains. Sample surface at different stages of the modification is characterized by the X‐ray photoelectron spectroscopy (XPS), Fourier‐transform infrared spectroscopy (FTIR), confocal microscopy, scanning electron microscopy–energy dispersive spectroscopy, and atomic force microscopy (AFM). Also the range of temperature‐dependent wettability tests (with water, hexadecane, and ethyleneglycol) is performed. The temperature controlled amphiphilicity switching is proved to be fully reversible and proceeding in seconds.
Ordered Mesoporous Carbons with High Micropore Content and Tunable Structure Prepared by Combined Hard and Salt Templating as Electrode Materials in Electric Double‐Layer Capacitors
Authors: Yan Runyu , Heil Tobias , Presser Volker , Walczak Ralf , Antonietti Markus , Oschatz Martin
Published: December 2017

Synthesis of high surface area carbon materials with hierarchical pore structure is reported. Combined salt templating with ZnCl2 and hard templating with SBA‐15 is used to produce ordered mesoporous and microporous hard–salt‐templated carbons (OM‐HSTCs) from simple sucrose as carbon precursor. OM‐HSTCs achieve specific surface areas of more than 2600 m2 g−1 and total pore volumes up to 2.2 cm3 g−1. In comparison to purely hard‐templated ordered mesoporous carbons, the additional salt template leads to high micropore volume and provides control over the size/distribution of micro‐ and mesopores and over the carbon microstructure. This method combines carbonization and the formation of well‐defined micropores in one step and is more versatile in terms of resulting pore structure than previously reported routes toward ordered mesoporous/microporous carbons. When applied as electrode materials in electric double‐layer capacitors with 1 m tetraethylammonium tetrafluoroborate in acetonitrile organic electrolyte, OM‐HSTCs combine high gravimetric capacitance (133 F g−1 at 0.1 A g−1) resulting from high micropore volume with high capacitance retention under high‐power conditions (126 F g−1 at 40 A g−1), exceeding the purely microporous or purely ordered mesoporous reference materials.
Green Nanotechnology from Waste Carbon–Polyaniline Composite: Generation of Wavelength‐Independent Multiband Photoluminescence for Sensitive Ion Detection
Authors: Goswami Sumita , Nandy Suman , Deuermeier Jonas , Marques Ana C. , Nunes Daniela , Patole Shashikant P. , Costa Pedro M. F. J. , Martins Rodrigo , Fortunato Elvira
Published: December 2017

This study reports on the qualitative analysis of photoluminescence effect generated from waste carbon of cooking oven by facile cost‐effective material engineering. The waste carbon product as a form of carbon nanoparticles (CNPs) is incorporated within a conjugate polymer, namely, polyaniline (PANI) to produce CNP‐PANI composites that have shown excitation‐wavelength‐independent triple‐band photoluminescence emission effect and highly sensitive Fe+3 ion detection ability. Herein the waste carbon material, while functionalized within the conjugated polymer, needs no further acid treatment or surface modification thus making the process cheaper, environmentally benign, and useful for green nanotechnology. The excitation‐wavelength‐independent unique triple‐band photoluminescence spectrum is the direct consequence of carbon–polyaniline synergy in π–π transition and the surface passivation of CNPs by the NH2 group rich aniline during in‐situ polymerization. The current scenario has been studied for the samples prepared with different CNP concentrations for different reaction times and discussed in details with supportive physico‐chemical characterizations. Moreover, the present study has demonstrated that the current material can be used as a fluorescent sensing platform for Fe+3 ions with high sensitivity and selectivity criteria where the detection limit of the sensing probe has a value as low as 12 × 10−9 nM.
Prospective transfrontal sheep model of skull‐base reconstruction using vascularized mucosa
Authors: Mueller Sarina K. , Scangas George , Amiji Mansor M. , Bleier Benjamin S.
Published: December 2017

Background

No high‐fidelity animal model exists to examine prospective wound healing following vascularized reconstruction of the skull base. Such a model would require the ability to study the prospective behavior of vascularized mucosal repairs of large dural and arachnoid defects within the intranasal environment. The objective of this study was to therefore develop and validate a novel, in vivo, transfrontal sheep model of cranial base repair using vascularized sinonasal mucosa.

Methods

Twelve transfrontal craniotomy and 1.5‐cm durotomy reconstructions were performed in 60‐kg to 70‐kg Dorset/Ovis Aries sheep using vascularized mucosa with or without an adjunctive Biodesign™ underlay graft (n = 6 per group). Histologic outcomes were graded (scale, 0 to 4) by a blinded veterinary histopathologist after 7, 14, and 28 days for a range of wound healing parameters.

Results

All sheep tolerated the surgery, which required 148 ± 33 minutes. By day 7, the mucosa was fully adherent with complete partitioning of the sinus and intracranial compartments. Fibroblast infiltration and flap neovascularization scores significantly increased between day 7 (0.3 ± 0.5 and 0.0 ± 0.0) and day 28 (4.0 ± 0.0, p = 0.01 and 2.0 ± 0.8, p = 0.01; respectively), while hemorrhage scores significantly decreased from 2.5 ± 0.6 to 0.0 ± 0.0 (p = 0.01). The inflammatory scores were not significantly different between the heterologous graft and control sides.

Conclusion

The described sheep model accurately reflects prospective intranasal wound healing following vascularized mucosal reconstruction of dural defects. This model can be used in future studies to examine novel reconstructive materials, tissue glues, and transmucosal drug delivery to the central nervous system.
Antisense suppression of glial fibrillary acidic protein as a treatment for Alexander disease
Authors: Hagemann Tracy L. , Powers Berit , Mazur Curt , Kim Aneeza , Wheeler Steven , Hung Gene , Swayze Eric , Messing Albee
Published: December 2017

Objective

Alexander disease is a fatal leukodystrophy caused by autosomal dominant gain‐of‐function mutations in the gene for glial fibrillary acidic protein (GFAP), an intermediate filament protein primarily expressed in astrocytes of the central nervous system. A key feature of pathogenesis is overexpression and accumulation of GFAP, with formation of characteristic cytoplasmic aggregates known as Rosenthal fibers. Here we investigate whether suppressing GFAP with antisense oligonucleotides could provide a therapeutic strategy for treating Alexander disease.

Methods

In this study, we use GFAP mutant mouse models of Alexander disease to test the efficacy of antisense suppression and evaluate the effects on molecular and cellular phenotypes and non–cell‐autonomous toxicity. Antisense oligonucleotides were designed to target the murine Gfap transcript, and screened using primary mouse cortical cultures. Lead oligonucleotides were then tested for their ability to reduce GFAP transcripts and protein, first in wild‐type mice with normal levels of GFAP, and then in adult mutant mice with established pathology and elevated levels of GFAP.

Results

Nearly complete and long‐lasting elimination of GFAP occurred in brain and spinal cord following single bolus intracerebroventricular injections, with a striking reversal of Rosenthal fibers and downstream markers of microglial and other stress‐related responses. GFAP protein was also cleared from cerebrospinal fluid, demonstrating its potential utility as a biomarker in future clinical applications. Finally, treatment led to improved body condition and rescue of hippocampal neurogenesis.

Interpretation

These results demonstrate the efficacy of antisense suppression for an astrocyte target, and provide a compelling therapeutic approach for Alexander disease. Ann Neurol 2018;83:27–39
Emissive Synthetic Cofactors: Enzymatic Interconversions of tzA Analogues of ATP, NAD+, NADH, NADP+, and NADPH
Authors: Hallé François , Fin Andrea , Rovira Alexander R. , Tor Yitzhak
Published: December 2017

A series of enzymatic transformations, which generate visibly emissive isofunctional cofactors based on an isothiazolo[4,3‐d]pyrimidine analogue of adenosine (tzA), was developed. Nicotinamide adenylyl transferase condenses nicotinamide mononucleotide and tzATP to yield NtzAD+, which can be enzymatically phosphorylated by NAD+ kinase and ATP or tzATP to the corresponding NtzADP+. The latter can be engaged in NADP‐specific coupled enzymatic transformations involving conversion to NtzADPH by glucose‐6‐phosphate dehydrogenase and reoxidation to NtzADP+ by glutathione reductase. The NtzADP+/NtzADPH cycle can be monitored in real time by fluorescence spectroscopy.
Loss of skills and onset patterns in neurodevelopmental disorders: Understanding the neurobiological mechanisms
Authors: Thurm Audrey , Powell Elizabeth M. , Neul Jeffrey L. , Wagner Ann , Zwaigenbaum Lonnie
Published: December 2017

Patterns of onset in Autism Spectrum Disorder, including a pattern that includes loss of previously acquired skills, have been identified since the first reports of the disorder. However, attempts to study such “regression” have been limited to clinical studies, that until recently mostly involved retrospective reports. The current report reflects discussion that occurred at an NIMH convened meeting in 2016 with the purpose of bridging clinical autism research with basic and translational work in this area. This summary describes the state of the field with respect to clinical studies, describing gaps in knowledge based on limited methods and prospective data collected. Biological mechanisms that have been shown to account for regression early in development in specific conditions are discussed, as well as potential mechanisms that have not yet been explored. Suggestions include use of model systems during the developmental period and cutting‐edge methods, including non‐invasive imaging that may afford opportunities for a better understanding of the neurobiological pathways that result in loss of previously‐attained skills. Autism Res 2018, 11: 212–222. © 2017 International Society for Autism Research, Wiley Periodicals, Inc.

Lay Summary

Loss of previously acquired skills, or regression, has been reported in Autism Spectrum Disorder since Kanner's reports in the 1950's. The current report reflects discussion from an NIMH convened meeting in 2016 with the purpose of bridging clinical autism research with basic and translational work in this area. This summary describes the state of the field regarding clinical studies and suggests use of model systems during the developmental period and cutting‐edge methods, for a better understanding of the neurobiological pathways that result in loss of previously‐attained skills.
An international qualitative study of functioning in autism spectrum disorder using the World Health Organization international classification of functioning, disability and health framework
Authors: Mahdi Soheil , Viljoen Marisa , Yee Tamara , Selb Melissa , Singhal Nidhi , Almodayfer Omar , Granlund Mats , de Vries Petrus J. , Zwaigenbaum Lonnie , Bölte Sven
Published: December 2017

This is the third in a series of four empirical studies designed to develop International Classification of Functioning, Disability and Health (ICF) Core Sets for Autism Spectrum Disorder (ASD). The present study aimed to describe functioning in ASD (as operationalized by the ICF) derived from the perspectives of diagnosed individuals, family members, and professionals. A qualitative study using focus groups and semi‐structured interviews were conducted with 19 stakeholder groups (N = 90) from Canada, India, Saudi Arabia, South Africa, and Sweden. Meaningful concepts from the focus groups and individual interviews were linked to ICF categories using a deductive qualitative approach with standardized linking procedures. The deductive qualitative content analysis yielded meaningful functioning concepts that were linked to 110 ICF categories across all four ICF components. Broad variation of environmental factors and activities and participation categories were identified in this study, while body functions consisted mainly of mental functions. Body structures were sparsely mentioned by the participants. Positive aspects of ASD included honesty, attention to detail, and memory. The experiences provided by international stakeholders support the need to understand individuals with ASD in a broader perspective, extending beyond diagnostic criteria into many areas of functioning and environmental domains. This study is part of a larger systematic effort that will provide the basis to define ICF Core Sets for ASD, from which assessment tools can be generated for use in clinical practice, research, and health care policy making. Autism Res 2018, 11: 463–475. © 2017 The Authors Autism Research published by International Society for Autism Research and Wiley Periodicals, Inc.

Lay Summary

The study findings support the need to understand the living experiences of individuals with Autism Spectrum Disorder (ASD) from a broader perspective, taking into account many areas of an individual's functioning and environment. The ICF can serve as foundation for exploring these living experiences more extensively by offering tools that enable wide variety of individual difficulties and strengths to be captured along with important environmental influences. As such, these tools can facilitate interventions that meet the needs and goals of the individual.
Ionic liquids for addressing unmet needs in healthcare
Authors: Agatemor Christian , Ibsen Kelly N. , Tanner Eden E. L. , Mitragotri Samir
Published: December 2017

Advances in the field of ionic liquids have opened new applications beyond their traditional use as solvents into other fields especially healthcare. The broad chemical space, rich with structurally diverse ions, and coupled with the flexibility to form complementary ion pairs enables task‐specific optimization at the molecular level to design ionic liquids for envisioned functions. Consequently, ionic liquids now are tailored as innovative solutions to address many problems in medicine. To date, ionic liquids have been designed to promote dissolution of poorly soluble drugs and disrupt physiological barriers to transport drugs to targeted sites. Also, their antimicrobial activity has been demonstrated and could be exploited to prevent and treat infectious diseases. Metal‐containing ionic liquids have also been designed and offer unique features due to incorporation of metals. Here, we review application‐driven investigations of ionic liquids in medicine with respect to current status and future potential.
Glutaraldehyde cross‐linking increases the stability of Lumbricus terrestris erythrocruorin
Authors: Rajesh Athul , Zimmerman Devon , Spivack Kyle , Abdulmalik Osheiza , Elmer Jacob
Published: December 2017

Since donated red blood cells must be constantly refrigerated, they are not available in remote areas and battlefields. We have previously shown that the hemoglobin of the earthworm Lumbricus terrestris (LtEc) is an effective and safe substitute for donated blood that is stable enough to be stored for long periods at the relatively high temperatures that may be encountered in remote areas. The goal of this study was to further increase the thermal stability of LtEc by covalently cross‐linking LtEc with glutaraldehyde (gLtEc). Our results show that the melting temperatures of the gLtEc samples steadily increase as the molar ratio of glutaraldehyde to heme increases (from Tm = 57°C for native LtEc up to Tm = 68°C at a ratio of 128:1). In addition, while native LtEc is susceptible to subunit dissociation at alkaline pH (8–10), cross‐linking with glutaraldehyde completely prevents dissociation of gLtEc at pH 10. Increasing the molar ratio of glutaraldehyde:heme also significantly increased the oxygen affinity of gLtEc, but this effect was decreased by cross‐linking gLtEc in the deoxygenated T state. Finally, while gLtEc samples cross‐linked at low G:H ratios (e.g., 2:1) exhibited slight increases in oxidation rate in Tris buffer, no significant difference in oxidation rate was observed between native LtEc and the gLtEc samples in Ringer's Solution, which contains antioxidants. Overall, cross‐linking LtEc with glutaraldehyde significantly increases its thermal and structural stability without any loss of function, making gLtEc an attractive blood substitute for deployment in remote areas and battlefields. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 34:521–528, 2018
Large‐scale culture of a megakaryocytic progenitor cell line with a single‐use bioreactor system
Authors: Nurhayati Retno Wahyu , Ojima Yoshihiro , Dohda Takeaki , Kino‐Oka Masahiro
Published: December 2017

The increasing application of regenerative medicine has generated a growing demand for stem cells and their derivatives. Single‐use bioreactors offer an attractive platform for stem cell expansion owing to their scalability for large‐scale production and feasibility of meeting clinical‐grade standards. The current work evaluated the capacity of a single‐use bioreactor system (1 L working volume) for expanding Meg01 cells, a megakaryocytic (MK) progenitor cell line. Oxygen supply was provided by surface aeration to minimize foaming and orbital shaking was used to promote oxygen transfer. Oxygen transfer rates (kLa) of shaking speeds 50, 100, and 125 rpm were estimated to be 0.39, 1.12, and 10.45 h−1, respectively. Shaking speed was a critical factor for optimizing cell growth. At 50 rpm, Meg01 cells exhibited restricted growth due to insufficient mixing. A negative effect occurred when the shaking speed was increased to 125 rpm, likely caused by high hydrodynamic shear stress. The bioreactor culture achieved the highest growth profile when shaken at 100 rpm, achieving a total expansion rate up to 5.7‐fold with a total cell number of 1.2 ± 0.2 × 109 cells L−1. In addition, cells expanded using the bioreactor system could maintain their potency to differentiate following the MK lineage, as analyzed from specific surface protein and morphological similarity with the cells grown in the conventional culturing system. Our study reports the impact of operational variables such as shaking speed for growth profile and MK differentiation potential of a progenitor cell line in a single‐use bioreactor. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 34:362–369, 2018
Sirens song or a bugle call to charge
Authors: Gilchrist Ian C.
Published: December 2017

Key Points

Radial access for catheterization is associated with reduced bleeding and mortality across a spectrum of clinical conditions compared to femoral.

Transradial technique is associated with a higher rate of access site failure but this is in those most likely to have a femoral‐based complication.

Improved outcomes will come with further radial technique refinement and not with a retreat to legacy femoral approaches.
Power of gradients
Authors: Yadav Pradeep , Eng Marvin H.
Published: December 2017

Key Points

Patients with high baseline gradients benefit most after TAVR.

In severe symptomatic aortic stenosis, every 10 mm Hg increase in mean gradient has 20% reduction in mortality after TAVR.

Low gradient severe aortic stenosis continues to be a clinical cohort with variable benefit from TAVR.
Toothpick ingestion and migration into the liver through the colonic hepatic flexure: case presentation, management, and literature review
Authors: El Asmar Antoine , Papas Yasmine , Hajj Imad , El Khoury Mansour
Published: December 2017

Key Clinical Message

The approach to toothpick ingestion and its complications should not be underestimated. The surgeon should be prepared for life‐threatening situations such as major vascular involvement, as well as highly specialized and technically challenging procedures, when the hepatic hilum is involved for instance. Referral to tertiary centers is sometimes mandatory.
Aprotic Lithium–Air Batteries Tested in Ambient Air with a High‐Performance and Low‐Cost Bifunctional Perovskite Catalyst
Authors: Cheng Junfang , Jiang Yuexing , Zhang Ming , Sun Yu , Zou Lu , Chi Bo , Pu Jian , Jian Li
Published: December 2017

Aprotic lithium–air batteries (LABs) with remarkably high energy density are facing some challenges, including insufficient cycle stability, high‐cost for applications, and unclear understanding about the mechanism. Seeking high‐performance and low‐cost catalysts is one of the effective solutions to resolve these problems. Perovskite oxide La0.6Sr0.4CoO3 (LSC) together with Fe and Mn doped materials La0.6Sr0.4Co0.2Fe0.8O3 (LSCF) and La0.6Sr0.4Co0.2Mn0.8O3 (LSCM) are prepared and applied as catalysts for LABs, which have been previously studied mostly in a pure oxygen atmosphere and rarely in ambient air. The results show that these catalysts are effective for LABs, and LSCF can improve the capacity and cycle number to 6027 mA h g−1 and 156 at current density of 400 mA g−1 in ambient air. The reasons for performance degradation of LABs tested in ambient air are discussed by EIS spectra and products analysis, which also clarifies the reason for improvement of the LSCF catalyst.
Immobilization of Molecular Catalysts for Enhanced Redox Catalysis
Authors: Fukuzumi Shunichi , Lee Yong‐Min , Nam Wonwoo
Published: December 2017

In the homogenous phase, redox catalysts are often deactivated by bimolecular reactions. For example, the charge‐separated state of photoredox catalysts decayed via bimolecular back electron transfer reactions between the charge‐separated molecules to decrease the lifetimes of the catalytically active species. When photoredox catalysts are immobilized on solid supports, the lifetime of the charge‐separated state was remarkably elongated to enhance the photocatalytic activity. Immobilization of photoredox catalysts on electrodes is required for photocurrent generation, leading to development of solar cells. Metal‐oxygen intermediates, which are active for oxidation of various substrates including water oxidation, are also deactivated via bimolecular reactions to produce inactive forms such as dinuclear metal bis‐μ‐oxo complexes. Immobilization of metal complex catalysts on solid supports prohibits the bimolecular deactivation, enhancing the catalytic activity and stability. This Review focuses on recent development of immobilization of both organic and inorganic molecular catalysts on various supports for enhancement of the catalytic activity, selectivity and stability in thermal and photoinduced redox reactions.
Potassium as a Structural Promoter for an Iron/Activated Carbon Catalyst: Unusual Effect of Component Deposition Order on Magnetite Particle Size and Catalytic Behavior in Fischer–Tropsch Synthesis
Authors: Chernavskii Petr A. , Pankina Galina V. , Kazantsev Ruslan V. , Eliseev Oleg L.
Published: December 2017

The structural and catalytic properties of nanosized Fe3O4 particles deposited on activated charcoal (AC) are drastically affected by the sequence of component deposition order. Preliminary alkalization of AC followed by Fe deposition leads to formation of small magnetite particles (modal size of 4 nm) with uniform distribution. This catalyst demonstrates much higher iron‐time yield in FT synthesis than counterparts prepared by co‐impregnation and sequential impregnation with a reverse order of component deposition (Fe, then K). The catalysts were characterized by nitrogen adsorption, X‐ray diffraction, transmission electron microscopy, temperature‐programmed reduction in Ar/H2, and CO/H2 flow and in situ magnetic measurements. After calcinations in argon, catalysts contain iron predominantly in the form of magnetite with minor amount of hematite in some cases. Activation of the catalyst in the CO/H2 stream prior catalytic test leads to the formation of surface Hegg carbide Fe5C2. Spent catalysts contain considerable amount of magnetite, which is presumably due to partial oxidation of carbide by water in the course of the FT reaction.
Size effect of mesoscopic‐scale silver particles on the adsorption capacity of silver/cotton for fuel oil desulphurization
Authors: Ai Shuo , Li Xinsheng
Published: December 2017

Thiophene and its derivatives in fuel oils, such as diesel, will be converted into SOx pollutants after combustion. Cotton is an inexpensive, sustainable biomass and a promising candidate for adsorbent supports because of its quasi‐one‐dimensional structure. Hence, we prepared silver/cotton adsorbents with silver loadings of 0.2, 0.8, and 4.3 wt% through a simple wet reduction method. Field emission scanning electron microscopy (FESEM) results show that when the silver loading was as high as 4.3 wt%, large silver aggregates were obtained; when the silver loading was as low as 0.2 wt%, small silver particles with diameters of ∼0.1 µm (mesoscopic scale) were primarily prepared. Static adsorption results demonstrated that the large silver aggregates were ineffective for the adsorption of thiophene, while the small silver particles showed an exceptional adsorption performance. At 30 °C, the highest thiophene adsorption capacity reached 10 mg/g on the 0.2 wt% silver/cotton adsorbent. The adsorption isotherm of the 0.2 wt% silver/cotton adsorbent was determined and exhibited a multi‐step trend. In addition, the bed pressure drop of the 0.2 wt% silver/cotton was determined to be 0.62 kPa/g, which was 26.0 % and 16.7 % of those of alumina and silica gel, respectively.
Ca(OH)2 Pre‐Treated Bentonite for Phosphorus Removal and Recovery From Synthetic and Real Wastewater
Authors: Markou Giorgos , Mitrogiannis Dimitris , Inglezakis Vassilis , Muylaert Koenraad , Koukouzas Nikolaos , Tsoukalas Nikolaos , Kamitsos Efstratios , Palles Dimitrios , Baziotis Ioannis
Published: December 2017

The performance of chemically pre‐treated bentonite with Ca(OH)2 toward ortho‐phosphate phosphorus (OPP) removal efficiency in synthetic (inorganic) and real (anaerobically digested effluents) wastewater (WW) is evaluated. The Ca(OH)2 pre‐treated bentonite displays a significant increase of OPP uptake (qe; mg P g−1 bentonite) of 40 and 15 times, reaching about 14 and 5.5 mg P g−1 for synthetic and real WW, respectively. The optimum pH for OPP sorption is 7, while at higher pH values, although OPP removal is high due to the precipitation in the liquid phase, the OPP removal in solid phase, that is, sorption onto bentonite surface is less compared to pH 7. Scanning electron microscopy (SEM) and X‐ray diffraction (XRD) analysis shows that OPP forms various complexes with co‐existing ions in WW, such as apatite (with Ca2+) and struvite (with and Mg2+). The most influential parameter of the pre‐treatment is the dosage of Ca(OH)2. Concentration of 0.5 M Ca(OH)2 or higher is necessary for an efficient pre‐treatment. In contrast, the concentration of bentonite does not affect the pre‐treatment efficiency, and a mass of 500 g L−1 bentonite is found to be sufficient. The chemical pre‐treatment with Ca(OH)2 renders bentonite a promising low‐cost sorbent for OPP removal and recovery from WW.
Live‐Cell Visualization of Calcium Flux in Vibratome‐Cut Thick Sections of Viable Tumor Tissue
Authors: Koh James , Hogue Joyce A. , Sosa Julie A.
Published: December 2017

This unit outlines a live‐cell imaging approach developed for visualization of intracellular calcium flux in human parathyroid tumors following stimulation of the calcium‐sensing receptor (CASR), a class C G protein–coupled receptor (GPCR). The primary assay readout, intracellular calcium release induced by activation of the inositol triphosphate receptor, is potentially generalizable to multiple other GPCR signaling events that utilize this common downstream signal transduction pathway. Advantages of the approach include: (1) preservation of native tissue context and positional information, allowing direct visualization of intratumoral functional heterogeneity; (2) quantitative documentation of reactivity to a physiological stimulus in an experimentally tractable ex vivo system; and (3) generation of a dynamic, functional classifier of tumor biochemical behavior to augment static marker assessment. The technical steps are performed in three sequential phases: (1) viable tissue sectioning; (2) fluorophore loading and tissue immobilization; and (3) live‐cell confocal microscopy. This versatile method provides a straightforward platform for functional characterization of human tumors. © 2017 by John Wiley & Sons, Inc.
Leptin Function and Regulation
Authors: Zhang Yiying , Chua Streamson
Published: December 2017

We summarize the biological impact of leptin signaling as well as the molecular and cellular characteristics of leptin action. Our focus is principally in the central nervous system and we describe the properties of the neuronal networks that are mediators of leptin's effects on ingestive behavior, energy balance, and the reproductive system. The molecular targets of leptin's effects are also responsible for the attenuation and termination of the intracellular signal transduction pathway for leptin, providing a clear understanding of the mechanisms leading to leptin resistance or insensitivity. Using the tools of comparative biology, we explore the potential functions of leptin in fish and birds. Based on the highly variable expression of leptin in multiple tissues, a clear lack of expression of leptin in adipocytes in numerous species of fish and birds and an absence of changes of leptin concentrations in blood that are correlated with changes in nutritional status, it is clear that leptin is unlikely to function as a signal for triglyceride stores in nonmammalian species. This comparative survey serves to highlight the unique function of leptin in mammalian biology as a modulator of energy balance, sexual development, and fertility. © 2018 American Physiological Society.Compr Physiol8:351‐369, 2018.
A Human Study to Evaluate Safety, Tolerability, and Cyclic GMP Activating Properties of Cenderitide in Subjects With Stable Chronic Heart Failure
Authors: Kawakami Rika , Lee Candace Y.W. , Scott Christopher , Bailey Kent R. , Schirger John A. , Chen Horng H. , Benike Sherry L. , Cannone Valentina , Martin Fernando L. , Sangaralingham S. Jeson , Ichiki Tomoko , Burnett John C.
Published: December 2017

Cenderitide is a novel designer natriuretic peptide (NP) composed of C‐type natriuretic peptide (CNP) fused to the C‐terminus of Dendroaspis natriuretic peptide (DNP). Cenderitide was engineered to coactivate the two NP receptors, particulate guanylyl cyclase (pGC)‐A and ‐B. The rationale for its design was to achieve the renal‐enhancing and antifibrotic properties of dual receptor activation, but without clinically significant hypotension. Here we report the first clinical trial on the safety, tolerability, and cyclic guanosine monophosphate (cGMP) activating properties of Cenderitide in subjects with stable heart failure (HF). Four‐hour infusion of Cenderitide was safe, well‐tolerated, and significantly increased plasma cGMP levels and urinary cGMP excretion without adverse effects with no change in blood pressure. Thus, Cenderitide has a favorable safety profile and expected pharmacological effects in stable human HF. Our results support further investigations of Cenderitide in HF as a potential future cGMP‐enhancing therapeutic strategy.
Electrodeposition of Nickel Nanoparticles for the Alkaline Hydrogen Evolution Reaction: Correlating Electrocatalytic Behavior and Chemical Composition
Authors: Tao Shasha , Yang Florent , Schuch Jona , Jaegermann Wolfram , Kaiser Bernhard
Published: December 2017

Ni nanoparticles (NPs) consisting of Ni, NiO, and Ni(OH)2 were formed on Ti substrates by electrodeposition as electrocatalysts for the hydrogen evolution reaction (HER) in alkaline solution. Additionally, the deposition parameters including the potential range and the scan rate were varied, and the resulting NPs were investigated by scanning electron microscopy and X‐ray photoelectron spectroscopy. The chemical composition of the NPs changed upon using different conditions, and it was found that the catalytic activity increased with an increase in the amount of NiO. From these data, optimized NPs were synthesized; the best sample showed an onset potential of approximately 0 V and an overpotential of 197 mV at a cathodic current density of 10 mA cm−2 as well as a small Tafel slope of 88 mV dec−1 in 1 m KOH, values that are comparable to those of Pt foil. These NPs consist of approximately 25 % Ni and Ni(OH)2 each, as well as approximately 50 % NiO. This implies that to obtain a successful HER electrocatalyst, active sites with differing compositions have to be close to each other to promote the different reaction steps. Long‐time measurements (30 h) showed almost complete transformation of the highly active catalyst compound consisting of Ni0, NiO, and Ni(OH)2 into the less active Ni(OH)2 phase. Nevertheless, the here‐employed electrodeposition of nonprecious metal/metal‐oxide combination compounds represents a promising alternative to Pt‐based electrocatalysts for water reduction to hydrogen.
Performance analysis of cooperative spectrum sharing using non‐orthogonal multiple access
Authors: Kader Md Fazlul , Shin Soo Young
Published: December 2017

This paper presents a cooperative spectrum sharing protocol using non‐orthogonal multiple access in cognitive radio networks. A 2‐phase protocol comprising of a primary transmitter‐receiver pair and a secondary transmitter‐receiver pair is considered. In the proposed protocol, 3 data symbols can be transmitted during the 2 phases; this is unlike the traditional decode‐and‐forward relaying where 1 data symbol can be transmitted and the conventional superposition coding–based overlay spectrum sharing and the cooperative relaying system using non‐orthogonal multiple access where 2 data symbols can be transmitted, under a single‐relay scenario. We have investigated performance of our proposed protocol in terms of ergodic sum capacity and outage probability along with analytical derivations over independent Rayleigh fading channels. We also compared our proposed protocol with the traditional decode‐and‐forward relaying, conventional superposition coding–based overlay spectrum sharing, and the cooperative relaying system using non‐orthogonal multiple access schemes to demonstrate efficacy of the proposed protocol. The simulation and analytical results are presented to confirm efficiency of the proposed spectrum sharing protocol.
Improving the use of environmental diversity as a surrogate for species representation
Authors: Albuquerque Fabio , Beier Paul
Published: December 2017

The continuous p‐median approach to environmental diversity (ED) is a reliable way to identify sites that efficiently represent species. A recently developed maximum dispersion (maxdisp) approach to ED is computationally simpler, does not require the user to reduce environmental space to two dimensions, and performed better than continuous p‐median for datasets of South African animals. We tested whether maxdisp performs as well as continuous p‐median for 12 datasets that included plants and other continents, and whether particular types of environmental variables produced consistently better models of ED. We selected 12 species inventories and atlases to span a broad range of taxa (plants, birds, mammals, reptiles, and amphibians), spatial extents, and resolutions. For each dataset, we used continuous p‐median ED and maxdisp ED in combination with five sets of environmental variables (five combinations of temperature, precipitation, insolation, NDVI, and topographic variables) to select environmentally diverse sites. We used the species accumulation index (SAI) to evaluate the efficiency of ED in representing species for each approach and set of environmental variables. Maxdisp ED represented species better than continuous p‐median ED in five of 12 biodiversity datasets, and about the same for the other seven biodiversity datasets. Efficiency of ED also varied with type of variables used to define environmental space, but no particular combination of variables consistently performed best. We conclude that maxdisp ED performs at least as well as continuous p‐median ED, and has the advantage of faster and simpler computation. Surprisingly, using all 38 environmental variables was not consistently better than using subsets of variables, nor did any subset emerge as consistently best or worst; further work is needed to identify the best variables to define environmental space. Results can help ecologists and conservationists select sites for species representation and assist in conservation planning.
Diaminoterephthalate Fluorescence Dyes – Versatile Tools for Life Sciences and Materials Science
Authors: Christoffers Jens
Published: December 2017

The 2,5‐diaminoterephthalate (DAT) structural motif is a powerful chromophore with remarkable fluorescence properties. Containing two carboxylate and two amino groups, it defines a colored molecular scaffold that allows for orthogonal functionalization with up to four different functional units. These compounds can be accessed in a remarkably simple fashion through reactions of succinyl succinates with amines, followed by aerobic oxidation, which is, from a preparative point of view, an issue of paramount importance. Even though DATs have been known since the beginning of the last century, compared to other classes of dyes they are so far underrated in the literature. This review highlights applications in life sciences and materials science. Equipped with maleimides and cyclooctyne moieties, for example, the chromophore can be covalently conjugated to biomolecules, which allows for the study of protein conformations and protein–protein interactions. In some cases, DATs serve as “turn‐on” probes, because their fluorescence quantum yields are increased by orders of magnitude upon reaction with the molecular target. Additionally, DAT fluorophores exhibit efficient emission in the solid state. By choosing appropriate substituents at the amino and carboxylate moieties, the emission wavelengths can be tuned in a broad range. As nanocrystalline needles, for example, DATs can be applied as fluorescence antennas for plasmon polaritons on a gold surface.
Base‐Catalyzed Formal [3+2] Cycloaddition of Diazooxindoles with Oxazol‐5‐(4H)‐ones
Authors: Zhao Hong‐Wu , Liu Yue‐Yang , Zhao Yu‐Di , Feng Ning‐Ning , Du Juan , Song Xiu‐Qing , Pang Hai‐Liang , Chen Xiao‐Qin
Published: December 2017

In the presence of DIPEA (diisopropylethylamine), a formal [3+2] cycloaddition reaction between diazooxindoles and oxazol‐5‐(4H)‐ones takes place easily to give new 3‐(1H‐1,2,4‐triazol‐1‐yl)indolin‐2‐ones in 61–98 % yield. The structure of the target molecules was confirmed by single‐crystal X‐ray structure analysis.